prompt_front: Now, answer the following question based on the text below, only give me the answer and do not output any other words.

Question: What is the sticking point in the political showdown over the budget?

Read the following text and answer briefly.

Context 1: CNN com - Transcripts
Tensions Boil Over possible government shutdown; New trouble targeting Gadhafi; Libyan Rebels in Panicked Retreat; Should U S  Recognize the Rebels?; Meeting With Gadhafi; Washington, D C  to Feel Burden of Shutdown; Religious Leaders Fast to Protests Cuts for Poor
WOLF BLITZER, HOST: Don, thanks very much 
Happening now, the top U S  general in charge of the military mission in Libya now expressing doubts that the opposition has the manpower to topple Moammar Gadhafi, as deadly new air strikes force rebel fighters into another retreat  This hour, I'll speak with a former Republican Congressman who's in Tripoli right now trying to get Gadhafi to step down 
Also, growing outrage across the United States, amidst new signs tomorrow's potential government shutdown may -- repeat may be unavoidable  Why one lawmaker is telling Congress -- and I'm quoting right now -- "go straight to hell "
And possible presidential hopeful, Donald Trump, on a mission to tell President Obama, "you're fired " We're fact checking his controversial investigation into the president's birth 
Up first, the political showdown over the budget, as tensions reach a boiling point about 31 hours until impending government shutdown  Just hours from now, President Obama will meet with Republican House speaker, John Boehner, and the Democratic Senate majority leader, Harry Reid, for further negotiations  Those talks scheduled to begin 7:00 p m  Eastern 
Hundreds of thousands of people across the country will be impacted by the shutdown  And we'll be bringing you examples throughout the next two hours 
One place it would be felt heavily is right here in Congress' backyard, the city of Washington  Washington, DC -- its spending is tied to the federal budget  And this major metropolitan area could lose millions of dollars while a number of critical services, like trash collection, for example, would be suspended for at least a week 
Today, an enraged Eleanor Holmes, the delegate representing Washington, DC, lit into Congress over the stalemate 
(BEGIN VIDEO CLIP) ELEANOR HOLMES NORTON (D), D C  DELEGATE: It's one thing to beat up on the District of Columbia  It's another thing drop a bomb on the city  And that's what this Congressional -- C R  does  It takes the route of authoritarian governments and dictatorships by dictating to a local government how it may spend its local funds  And it may force the District of Columbia government to shut down, although our government had a balanced budget 
BLITZER: And get this -- the members of Congress charged with reaching a deal, they'll still be receiving a paycheck if there's a shutdown, despite the hundreds of thousands of government employees who won't be receiving any paychecks  The current Congressional salary, by the way, $174,000 a year 
Our CNN senior Congressional correspondent, Dana Bash, is up on Capitol Hill with the latest developments -- Dana, specifically, where are the sticking points right now?
DANA BASH, CNN SENIOR CONGRESSIONAL CORRESPONDENT:
Well, look, Wolf, this is effectively a bill to fund the government  And the sticking points certainly are about how much spending to cut  That's what this whole issue has been about 
However -- however, one of the main issues, I am told, that were just -- that was discussed at the White House meeting this afternoon with the president, the House speaker and the Senate majority leader, was over not necessarily spending measures, but over lightning rod issues like regulating greenhouse gases and abortion 
BASH (voice-over): One of the biggest disagreements is not over government spending, but policy 
REP  JOHN BOEHNER (R-OH), SPEAKER OF THE HOUSE: Some 40 or 50 policy restrictions that were attached to -- to our bill 
BASH: So-called policy riders Republicans call essential and Democrats call nonstarters  The most divisive is over abortion  A GOP plan to cut all federal funding for Planned Parenthood, which provides abortion procedures in addition other women's health services 
SEN  HARRY REID (D-NV), MAJORITY LEADER: This is a budget  This is to keep our country running  This is not a woman's health bill 
BASH: Planned Parenthood staged a rally outside the Capitol to protest 
CECILE RICHARDS, CEO, PLANNED PARENTHOOD: They don't want to allow Planned Parenthood to serve the three million women that we see every single year  Ninety-seven percent of the services Planned Parenthood provides are preventive care 
UNIDENTIFIED MALE: I certainly don't think that taxpayers should subsidize abortions  It's -- if a woman chooses to have an abortion, it's legal to do that in this country  But I don't think taxpayers should be put in a position to have to pay for those abortions 
BASH: Another major sticking point -- how much spending to cut  A Democratic source tells CNN they have finally tentative agreement on slashing $34 5 billion from the rest of this year's budget  But a Republican source says there's no deal 
BOEHNER: There is no agreement on the number  There are no agreement on the policy issues that are contained with it 
BASH: Then there's the critical issue of what programs and agencies to cut  Democrats say they're trying to find spending cuts with the least impact on those who need it most  So they're pushing for things like temporary one year cuts in programs  Some examples, cuts in wetlands protection and Pell grants for summer school and graduate students 
Republicans call that smoke and mirrors 
BOEHNER: And our goal is to make real spending cuts 
BASH: Some examples of what Republicans want to cut -- money for food inspectors, Head Start education programs and funding for housing 
BASH: This afternoon, House Republicans did pass a bill to keep the government running for one week past tomorrow's midnight deadline  It has $12 billion in cuts  It would fund the Defense Department for the rest of the year  But Democrats, including the president of the United States, call it a distraction and they say that they really want to keep the focus on what they're negotiating, which is a bill that would keep the government open -- keep the government functioning and funded for the rest of the year 
BLITZER: And the president's playing hardball  He's saying he'll veto that legislation --
BASH: He was, yes 
BLITZER: -- if it were to pass the Senate and come to his desk  I hear, Dana, that some employees already are getting furloughing notices 
BASH: It's true  This is just preventive  But all across the Capitol here today, people in offices and -- and -- well, really, everywhere -- were told whether or not, if, in fact, it does come to a government shutdown, if they're going to be here or not  And this is an example  We obtained one of the furlough notices  And I'll just read you a line  This -- imagine if this came across your desk  It says: "Because your services are not needed for the orderly suspension of operations and you're not engaged in one of the accepted functions, you're being placed on furlough effective Saturday, April 9, 2011 "
Now, again, of course, this is just protective  The government is still open  But interesting that they're already getting ready for a government shutdown and telling people who will come to work and not 
One more note  Even people who are here, who are called essential, they're not going to get paid, either 
BLITZER: All right, Dana 
Don't go too far away 
We'll be in close touch 
The impact of the potential government shutdown is even being felt on the front lines of combat in Afghanistan  And Iraq  The Defense secretary, Robert Gates, is in Iraq right now  And he's telling U S  troops they will feel a pinch 
ROBERT GATES, SECRETARY OF DEFENSE: I hope they didn't have you standing out here in the sun too long
If -- if the government shutdown starts on the 8th and goes for a week, you'd get a half a check  If it goes from the 15th to the 30th, you wouldn't get a paycheck on the 30th but you would be back paid for all of it  So that's -- that's the deal 
BLITZER: Not great deal 
Gates also told the troops this would likely be his last trip to the country as Defense secretary and he wanted to say thank you 
He's expected to retire later this year 
Now to the deadly stalemate in Libya  New signs the military operation in the region is facing some tough new challenges 
Our Pentagon correspondent, Barbara Starr is here 
She's watching the story 
She's got more 
What are you learning? BARBARA STARR, CNN PENTAGON CORRESPONDENT: Well, Wolf, there was very dramatic, very hard-nosed testimony today on Capitol Hill from the top U S  commander responsible for the U S  involvement in Libya, saying that Gadhafi forces are becoming increasingly difficult to target, as they are using civilian vehicles, mixing in with local populations, moving next to mosques, schools, hospitals -- all the same tactics we saw for years in Iraq 
And now, all of this today leading to a very dramatic exchange between General Carter Ham and one of the most vocal administration critics, Senator John McCain 
SEN  JOHN MCCAIN (R), ARIZONA: Hearing your testimony, General Ham, is almost an Orwellian experience for me  The fact is that if we had imposed the no-fly zone three weeks, four weeks ago, Gadhafi would not be in power today 
The fact is that the situation on the ground is basically a stalemate 
Would you say that the situation on the ground is a stalemate or an emerging stalemate?
GEN  CARTER HAM, COMMANDER, U S  AFRICA COMMAND: Senator, I -- I would agree with that if present on the ground 
MCCAIN: So the goal -- our policy objective of the removal of Gadhafi is further from being achieved than it was three or four weeks ago 
HAM: Senator, I -- I don't know that I would agree with that  What I -- because that, again, was not a military mission  The military mission of protecting, I think, was not wholly achieved, but achieved in large part 
STARR: General Ham also acknowledging another problem -- a key U S  aircraft, the AC-130, that flies low and slow to target on the ground, is facing what he called "a significant threat" from surface to air missiles, which he said remain effective and operational in some cases 
And, Wolf, get this  General Ham says there were about 20,000 of those surface to air missiles when the campaign started and they are concerned that an awful lot of them are still out there -- Wolf 
BLITZER: Barbara, thanks very much for that report 
Panicked rebels are once again on the retreat from Gadhafi's forces  Just today, at least three people were killed, another 10 injured, in new air strikes  And there are mounting questions about whether NATO could be responsible for the attack 
Our senior international correspondent, Ben Wedeman, is joining us now from Benghazi 
Ben's watching all of this closely 
You just heard General Ham, who is the commander of the U S  military's Africa Command  He was in charge of the mission before handing over complete control to NATO  You just heard him say there could be a stalemate out there 
What's the sense on the ground?
BEN WEDEMAN, CNN SENIOR INTERNATIONAL CORRESPONDENT: Well, the sense was a few days ago that it was, indeed, a stalemate -- sort of a seesaw battle that went back and forth between Ajdabiya and Brega 
But what we saw today was that that seesaw was tipped over  And it was a general retreat by the opposition forces from somewhere near Brega to almost the other side of Ajdabiya  This, after this air strike, which almost everybody on the ground believes to be NATO leaving not three, but four people dead  And many others are still unaccounted for 
That set off this general retreat whereby we saw all their heavy -- all of the opposition forces' heavy equipment -- multiple rocket launchers, tens and tens of these pickup trucks mounted with heavy machine guns streaming through Ajdabiya to the other side, the far side of the city  Some of them going all the way back to Benghazi, according to the head of the rebel forces in the eastern part of the country, Abdul Fatah Younis  He says that the Gadhafi forces were approaching Ajdabiya from three different directions 
I would not call that a stalemate -- Wolf 
BLITZER: Ben, you got a close-up look at some of the casualties today out on the front lines 
WEDEMAN: It's very bad, very bad  I mean it wasn't just fighters  It was also medics who had gone to the scene of this reported air strike, which then got hit again  So one of them was a doctor, one of them was a medic  And we were in the hospital  And there was real anger at NATO, anger at the fact that when they needed those air strikes on the Gadhafi forces, they weren't getting them  And now, for the second time in a week, there's been another strike  Now, of course, we must stress that NATO says that they -- because they don't have enough boots on the ground, they can neither confirm nor deny this was a NATO strike  But certainly, speaking to eyewitnesses in the hospital, it certainly sounded like an air strike  And there are no other planes in the skies of Libya other than NATO planes -- Wolf 
BLITZER: Ben Wedeman in Benghazi for us 
The U S  says Moammar Gadhafi is no longer the legitimate leader of Libya 
So why not recognize the rebels?
Why one U S  official says it raises serious concerns 
And a former U S  Congressman in Libya armed with a message for the Libyan dictator 
Will he get to meet with him face-to-face?
My interview with Curt Weldon, that Republican former Congressman -- that's coming up, as well 
BLITZER: Let's get right to Jack 
He's got some nuclear concerns on his mind with The Cafferty File -- Jack 
JACK CAFFERTY, THE CAFFERTY FILE: Well, they had another little temblor in Japan -- a 7 1 magnitude earthquake hit Northeastern Japan today, the strongest aftershock since that massive 9 0 quake and tsunami that followed devastated that nation four weeks ago  And this one today was in roughly the same area 
One of the big concerns, of course, is possible further damage to the Fukushima Daiichi nuclear power plant  The Tokyo Electric Power Company, TEPCO, which operates the plant -- or what's left of it -- said there were no serious incidents as a result of today's aftershock 
So they say  Radioactivity from that plant has poisoned the surrounding land, air and ocean  Millions of people have been exposed  Millions more could be, as radioactivity has been picked up in food and drinking water and detected in faraway places, like California 
This week, workers plugged a crack in the plant that had been gushing contaminated water into the ocean for weeks  As a result, TEPCO says now radiation levels in the ocean waters off the coast there have dropped dramatically 
Yesterday, the head of the United Nations' scientific committee on the effects of atomic radiation said the Fukushima accident is not expected to have any serious impact on the health of the Japanese people  He said, quote: "We have seen traces of iodine in the air all over the world, but they are much, much, much lower than traces we have seen at similar distances following Chernobyl," unquote 
Well, not everybody is convinced  In South Korea, more than 130 primary schools and kindergartens ordered closed today outside of Seoul  People there were worried that windy, rainy weather could be carrying radioactive material from Japan 
North Korea aired warnings on television for its people to stay indoors during that rain storm and to take a full shower if they were caught outside in the storm 
Even here in the United States, some chefs are now using sensors to test levels of radiation in the fish they plan to serve in restaurants 
Here's the question -- do you think you're being told the truth about the nuclear accident in Japan?
If your -- if your trout is he glowing, Wolf --
BLITZER: Yes?
CAFFERTY: -- you might want to send it back and get a ham sandwich 
BLITZER: You want it well done, but not necessarily that well done 
CAFFERTY: No 
BLITZER: All right, Jack 
Not a laughing matter 
BLITZER: Serious stuff 
CAFFERTY: Right 
BLITZER: See you in a few moments 
New questions this hour about the capabilities of the rebels in Libya and whether they have the power to overthrow Moammar Gadhafi 
Should the United States -- should the United States have a hand in helping arm the rebels?
Let's bring in our foreign affairs correspondent, Jill Dougherty, with this part of the story 
What are you hearing over at the State Department -- Jill  JILL DOUGHERTY, CNN FOREIGN AFFAIRS CORRESPONDENT: Well, you know, Wolf, other countries have done it, other countries like France and Italy have done it -- recognizing the opposition  And supporters say now, with the rebels in retreat, the U S  shouldn't wait 
But what would it really change anything?
DOUGHERTY (voice-over): The U S  says Moammar Gadhafi is no longer the legitimate leader of Libya 
Secretary of State Hillary Clinton is full of praise for them 
HILLARY RODHAM CLINTON, SECRETARY OF STATE: These were not soldiers  These were not trained military forces  They were doctors and lawyers and university professors and economists and, you know, young men who were students  And they are being attacked by mercenaries, by ruthless forces that Gadhafi is utilizing to show no mercy against his people  And they are courageous  They are moving as fast as they can to try to form themselves into a military operation 
DOUGHERTY: Clinton has met with the rebel leaders personally, but the administration still is cautious  The president authorized the CIA to send in agents to learn about the rebels and assess their needs  Clinton's special representative, the State Department's Christopher Stevens, seen here in 2008 in Tripoli, is on the ground in Benghazi, scoping them out 
MARK TONER, U S  STATE DEPARTMENT SPOKESMAN: We sent somebody in to get that kind of on the ground assessment of the -- of -- of their identity, of their leadership structure, to talk with them firsthand and to see what direction we think they're moving in  We've seen some positive signals 
DOUGHERTY: Recognizing the rebels, a senior official tells CNN, raises serious issues  It would acknowledge that Libya is now a divided country 
And could the U S  be sure the group represents the whole opposition movement?
It's a bit early, this official says  Maybe they turn out not to be the right folks 
But Secretary Clinton knows the timing is urgent 
CLINTON: What NATO is doing is buying time, buying space 
DOUGHERTY: So far, the U S  is providing what's called non- lethal humanitarian aid  The administration hasn't yet decided to arm them or provide financial assistance 
DOUGHERTY: But a senior U S  official tells CNN there's a lot the United States could be doing right now without going so far as to recognize the rebels, pointing out that the U S  funds political groups and other organizations around the world  But this official says you want to be careful about who they are 
So, so far, caution seems to be winning out over urgency -- Wolf 
Jill is at the State Department 
The House speaker, John Boehner, may be doing double duty if the government shuts down this weekend  You're going to find out why he could be cleaning up a lot of trash in his own backyard 
And a former U S  Congressman now on a mission to meet with Moammar Gadhafi in Tripoli in person  Curt Weldon, he's here  He'll join us in THE SITUATION ROOM from Tripoli  You're going to find out who he says would be a good replacement for the embattled Libyan leader 
BLITZER: Military leaders have a message for Congress about "don't ask/don't tell "
Well, military leaders say preparations for repealing "don't ask/don't tell" are going better than they expected  They testified before a House committee today about getting rid of the policy that bars openly gay service members  They caution, though, that it will take time and training to implement the repeal  And it must still be certified by President Obama, the Defense secretary and the chairman of the Joint Chiefs of Staff 
Well, your Smartphone just got a little smarter  The FCC is requiring that wireless carriers provide access to the mobile Internet anywhere it's available, even when it's offered by a competing provider  And that could be a huge -- make a huge difference to smaller carriers, who told the FCC they just can't compete otherwise against industry heavyweights like Verizon and AT&T 
New York City school chancellor, Cathie Black, is stepping down after only three months on the job  Mayor Michael Bloomberg says her short stint just didn't work out as either of them had expected or hoped  Her approval rating has plunged to 17 percent 
Black chaired "First" magazine before overseeing the nation's largest school system  Deputy Mayor Dennis Walcott will replace her 
And a war of words is erupting between an emerging Republican star, New Jersey Governor Chris Christie, and his state's largest teachers' union  In a network TV interview, Christie called the union leaders, quote, "political thugs " He blames them for teacher lay-offs that he says could have been avoided if they had not opposed salary freezes  The New Jersey Education Association is firing back, accusing Christie of name-calling -- Wolf 
BLITZER: Sticks and stones will break many bones 
SYLVESTER: Sticks and stones may break my bones --
SYLVESTER: But words never hurt me 
A former U S  Congressman is in Tripoli, Libya right now  His goal -- to talk to Moammar Gadhafi  His message -- we'll talk about that  My interview with Curt Weldon coming up next 
Plus, we showed it to you earlier -- a member of Congress telling colleagues to, quote, "go to hell "
Now she's is joining us live here in THE SITUATION ROOM to explain 
HOLMES NORTON: -- of Columbia  It's another thing to drop a bomb on a city  And that's what this --
BLITZER: Former Congressman Curt Weldon is in a -- Weldon is on a mission to Libya right now to try to meet with the embattled leader, Moammar Gadhafi  But that may be easier said than done 
Joining us now from Tripoli, former Republican Congressman Curt Weldon of Pennsylvania  Congressman, thanks very much for coming in 
And joining us now from Tripoli, former Republican Congressman Curt Weldon of Pennsylvania 
CURT WELDON, FORMER U S  CONGRESSMAN: My pleasure, Wolf 
BLITZER: Let's talk about your meeting with Moammar Gadhafi  I take it it has not yet happened 
Do you expect to meet with the Libyan leader? WELDON: Absolutely  The invitation that was sent to me was from his chief of staff, Bashir Salah, who I've met on all three of my official visits here in 2004 and 2005  And the letter specifically says we want you to come over and meet with the leader and our senior leadership 
And I said it's worth me coming over to support the administration and to try to let the leader know face to face that this is facing -- it's very grave timing in the situation and they have to have some movement fairly quickly or they're not going to be happy with the -- with the alternatives 
BLITZER: What's taking so long?
Why haven't you been able to meet with Gadhafi yet?
WELDON: Well, it -- that's not unusual  I mean all three of the delegation trips that I led here in 2003 and 2004 -- or, actually, 2004 and 2005 -- they always make you wait until 30 minutes before the meeting and then you go  And some of those meetings were at 10:00 at night, some were at 5:00 in the afternoon 
As you know from the excellent reporting being done by your folks here, there's a lot of security concerns, and they are very concerned where Gadhafi is at any given moment  That's one of the issues, but we have been making ourselves available 
We have been doing a lot of back-channel meetings with friends and associates that I have here, and we have met with the chief of staff and one of the sons, and today with the prime minister, a very lengthy meeting for two hours  So, we're going to give them until tomorrow  We're not going to stay beyond that  And we have given them some suggestions, and we expect a response by midday tomorrow  And if we don't, we will done exit conversation with your people and let you know our feelings 
BLITZER: What's the major headline that you got out of these meetings with other leaders? I take it you met with Saif Al-Islam Gadhafi, one of the sons of Moammar Gadhafi  What are they saying to you?
WELDON: Well, we actually didn't meet with Saif  I have met with Saif probably 10 times over the past seven years, both in America and here in Libya  I have not yet met with Saif  I have offered, if he is available 
I have met with Saadi  And the general thrust is obviously that they want peace and they want to find a way out of this  But as I have explained to them, there's certain things that have to be done according to our president and our secretary of state, who I'm here to support 
We don't have a different agenda  There's no compromise on our part  Our only mission here is to talk face to face with them and say this is reality and this is a grave situation, and you need to do certain things that we suggest that we think will get our administration to respond to your actions  And again, we're not doing any negotiating 
They know me, they have seen my efforts  I have not taken anything from their country in the way of financial benefits, and I'm here only because I want to avoid war  I don't want to see American soldiers killed, and I don't want to see more innocence Libyans killed 
BLITZER: You wrote an op-ed in "The New York Times" this week saying that once you meet face to face with Moammar Gadhafi, you will tell him to step down  Is that still your intention?
WELDON: Absolutely, Wolf  I wrote the op-ed before the trip was planned  And I wrote it, Wolf, because back in 2004, when I led the first delegation of Americans to sit down with him in the tent in Tripoli, he said to me, "Congressman, why did it take 30 years for someone from your country to come and sit with me and tell me to my face that you believe that I'm a criminal and a terrorist  And then if you didn't believe me, bomb me?"
And I said, "Leader, I can't explain that " So I said now it's time for someone to sit in a tent face to face with Colonel Gadhafi and let him know how grave this situation is 
And I'm willing to do that  And I think I'm probably the best person because I have met with him three times, and because I sat in that tent in 2004 and listened to him tell me that  So, in effect, that's why I'm here 
BLITZER: You wrote also in "The New York Times" this -- you wrote, "Colonel Gadhafi's son, Saif, a powerful businessman, a politician, could play a constructive role as a member of the committee to devise a new government structure or constitution "
You know, a lot of people, including the opposition, the rebels, as they're called, they think Saif Al-Islam Gadhafi is just as much a killer or thug as his father is, and they say they have no interest in dealing with him either 
What do you say to that criticism?
WELDON: Well, what I said, I'm not endorsing anything anyone for any office here  What I am hoping for is what the president wants, which is a free and fair election to take place, hopefully sooner rather than later 
But having been involved with Libya for seven years, I was a witness to the work that Saif did in the Lockerbie case, the La Bella nightclub bombing  I personally witnessed through the Gadhafi Foundation the work that Saif did to free up the Bulgarian nurses who were sentenced to death twice, along with a Palestinian doctor 
I have seen the work that Saif and Dr  Salani (ph) at the foundation have done in dealing with chemical weapons destruction and with the elimination of landmines and humanitarian efforts worldwide  I have been out to (INAUDIBLE), the chemical weapons plant, and I have actually seen visibly how they have removed the chemical weapons production materials  He was behind all of that 
Believe me, Wolf, I'm not happy with some of the statements and the actions that he's made over the past month, and he knows I'm not happy  But I think in a fair election, up until now, he should be given the opportunity to seek office where he can run against other candidates, perhaps, for the presidency  And so I would at this time think that he should be allowed that opportunity 
That's not to say I condone anything that he said or his actions  He will have to be accountable for those on his own 
BLITZER: Because you make him sound like he's a decent guy when so many people think he is a killer, a murderer, especially given the statements that he recently made, that if he goes into Benghazi, if he finds these rebels, he will go and kill them all  You make it sound like he's a decent guy 
WELDON: Well, I -- you know, I haven't been with him on a continual basis  I have met with him a number of times, both in the U S  and here, under some very stressful situations, especially when it came to resolving the Lockerbie case and the La Bella nightclub  And despite what Sarkozy said about resolving the issues of the Bulgarian nurses when they were sentenced to death twice, it was Saif who played a very critical role against some very powerful forces in this country that wanted to kill those people 
You know, I don't know of any incidences where I, first hand, have seen evidence of him committing human rights violations, and if he did, he has to be held accountable like everyone else  And I have said that publicly and I will say that privately 
So my judgment is just based upon my experience with him, the fact that he is a knowledgeable person, he understands the need to interact and interface with the West  I think he could be a viable candidate  But ultimately, my opinion is hopefully going to be the opinion of the Libyan people 
BLITZER: Because you probably have seen all of the articles, the reports over the past month, month and a half, of mass murder, of killings, not only by Saif Al-Islam, but some of his brothers that have gone on, the atrocities that have been so widely reported  I hear what you're saying about his role over the recent years when the Bush administration, and later the Obama administration, was trying to improve relations with Libya, but over the past several weeks, based on all of the international reporting we have seen, it's been a brutal record that he has accomplished 
WELDON: Well, again, I don't have firsthand evidence of that  I just got here two days ago  And I fully support an international tribunal to look at human rights violations on everyone in this country  That's necessary  And if they find evidence that he has been involved in that, then he should suffer the consequences of his actions 
(END VIDEOTAPE) BLITZER: In our next hour, part two of the interview with former congressman Curt Weldon  There have been some questions raised about his motive  Is he in all of this for the money? You're going to find out his answer to that and more  Stand by 
Also, Washington, D C 's congressional delegate is telling colleagues -- and I'm quoting her now -- "Go to hell " She is joining us live in THE SITUATION ROOM to tell us why 
Plus, no budget deal, no food -- the extreme tens of thousands of people are going to as a government shutdown looms 
BLITZER: Let's get back to the outrage boiling over on Capitol Hill, only hours before a potential government shutdown 
Joining us now, the Democratic delegate representing the city of Washington, D C , Eleanor Holmes Norton 
ELEANOR HOLMES NORTON (D), D C  DELEGATE: Of course, Wolf 
BLITZER: I think it's fair to say that Washington, D C , a city of a population of about 600,000 people, the only major metropolitan -- the only major city in the United States that's going to foal the direct impact of a federal government shutdown so dramatically, so powerfully, because it is a federal district 
Give me an example of what's going to happen if there's a government shutdown 
NORTON: Absolutely, although your viewers will be shocked by what they are about to hear 
They know a little bit about taxation without representation -- we pay our taxes, then we have full representation in the House and the Senate  But I bet they didn't know that our local budget, without a dime of federal money in it -- and we support ourselves almost entirely -- has to be sent to the masters in the Congress to sign off on it before we can spend our own local money 
Well, listen to this, Wolf  We passed our budget in -- last spring  The appropriators signed off on it last summer 
So, why are we in a federal budget fight over their money when it is our money I am talking about? I have put forward amendments that said the district can spend its own local funds 
BLITZER: What's going to happen in the District of Columbia Saturday, Sunday, Monday, if there is a government shutdown? Give me an example or two 
NORTON: I will give you some dramatic ones  How about the shutdown of the D C  government itself? Because since the final gavel hasn't fallen on all the federal appropriations, then the district government has now prepared to shut down on Saturday morning just because the federal government is shutting down 
We are at the height of the tourist season, the Cherry Blossom Festival  That has been severely curtailed because of the federal shutdown  That's going to -- three million people come here just in one month for the cherry blossoms  Our mayor has had to put out a list of agencies that will be open and a list of agencies that won't be open 
BLITZER: Trash collection -- will there be any trash collection in the District of Columbia?
NORTON: No trash collection, and some residents have started up a Facebook page that says if they close down the District of Columbia, we're carrying our trash to Speaker Boehner's House 
BLITZER: You don't support that do you?
NORTON: I do not 
NORTON: And let me just say right here, I do not  But let me tell you, I am only expressing a little of the rage that the taxpaying residents of the District of Columbia are feeling 
BLITZER: But let me ask you this, Congresswoman, because the Democrats were in control, they had a large majority in the House all of last year; in the Senate, a significant majority  They failed to pass a budget  Don't the Democrats deserve a lot of the blame for this current impasse?
NORTON: Absolutely not, because the Democrats would never have held our budget up here 
LISA BLOOM, CNN LEGAL ANALYST: Why didn't they pass the budget?
NORTON: Well, that doesn't have anything to do with us  This is our local money 
All it would take is -- the Democrats in the Senate are ready to agree  The president is ready to sign an amendment --
BLITZER: But they could have done this any time last year 
NORTON: Wait a minute, Wolf  Wait a minute -- an amendment that said while we're fighting it out on the federal budget, we will let the district spend its own local funds 
So that's all I'm asking  I'm not in this fight, so don't ask me why the Democrats didn't pass the Democratic budget 
I passed -- we passed our budget  Our budget is balanced  The only issue before the Senate and the House is, can we spend our local money? It doesn't have anything to do with their budget 
They can go on from now until Timbuktu  Let us spend our money and don't close down our city because the federal government can't get its act together 
BLITZER: I'm with you there  This is an outrage, the fact that there is -- if there is going to be shutdown  I'm still hoping there won't be a shutdown, but it's --
NORTON: I think there may not be 
BLITZER: -- ridiculous when you think about it, when you think about how close they are  It would be a horrible, horrible tragedy, because 800,000 people directly are going to start losing their paychecks  And the District of Columbia, which is, as you point out correctly, taxation without representation, is going to suffer a great deal more than any other city in the United States 
Good luck, Congresswoman  Thanks very much 
NORTON: Thank you, Wolf 
BLITZER: I feel your pain 
Concerns within military families over a government shutdown  Also, why they are downright scared they won't be able to put food on the table 
And tens of thousands of people on a hunger strike, including some members of Congress  We'll explain why 
CAFFERTY: The question this hour is: Do you believe you're being told the truth about the nuclear accident in January?
Fred writes, "You want the truth? You can't handle the truth "
"Just how should a government balance our right to know the truth with the perceived need to not create a panic and thus a larger problem? Can you really evacuate a million people? To where? Yes, without the truth, how can anyone try to act reasonably?"
"In the end, we do have a right to know the truth  Honesty is the best policy "
Paul in Ohio writes, "Jack, I believe they're telling what they think they know with certainty  It is most certain that they don't know everything "
Jeremy in California, "So I'm confused  Is the current California radiation level 'harmless to human health,' 'not immediately harmful to human health,' not permanently harmful to people outside the region,' or no more than an apples-to-oranges transcontinental flight?"
Craig writes, "Perspective  In Japan, they have had yet another earthquake and have lived in fear and chaos for over a month  And yet, their government hasn't shut down  Nuclear disaster, natural disaster, absolute destruction hasn't kept their elected officials from doing their duty to the people 
"Yet, in America, we get Harry Reid, John Boehner and a White House who are more concerned with the 2012 election campaign  It's times like these when we see just how far off the mark we really are "
Louis writes, "No  Just too many things going wrong  They say that the seafood will be safe  I ask this: Do fish migrate or do they set up housekeeping in one spot and then stay there? And if so, why don't I catch fish in the same place every day?"
And Jim in Colorado, "The nuclear industry telling the truth? The unicorn, garden gnome and I were talking this over just the other day, and we all agreed it could happen  Why not?"
If you want to read more about the unicorn and the garden gnome, go to CNN com/CaffertyFile 
BLITZER: We will, for sure, Jack  Thank you  See you in a few moments 
Several sticking points in the ongoing budget negotiations, but will the government shutdown come down to money or social issues?
Plus, Donald Trump, he's making allegations about President Obama's birthplace  Does Donald Trump have any grounds for any of that? We're digging deeper for answers 
BLITZER: The growing outrage over the budget crisis isn't just about Congress' failure to reach a deal, it's also about some of the cuts that are being proposed 
Lets bring in our own Lisa Sylvester once again  She has the details -- Lisa 
Well, as congressional leaders hammer away on a budget compromise, a group of religious leaders have been fasting and praying to raise awareness of cuts in the budget that they say will harm the poor 
JIM WALLIS, PRESIDENT, SOJOURNERS: Orange juice never tasted so good 
SYLVESTER (voice-over): It's been 10 days since Jim Wallis last had solid food  The president of Sojourners, a Christian group that advocates for the underprivileged, is leading the charge among faith groups on a hunger fast to protest proposed cuts in the federal budget for the poor 
WALLIS: We're saying a budget is a moral document  And whether at your kitchen table, as a family, or a church or a nation, you make choices  What's important, what's not?
SYLVESTER: Wallis said in the last 10 days, more than 30,000 people around the country have joined in the fast in their own way  He says they have become a bit like God's lobbyists for the poor, putting a theological and moral spin on the cuts  Wallis said he is all for deficit reduction but --
WALLIS: I don't think doing this at the expense of the poorest people is a good choice, or hurting those who are already hurting the most is moral or even is smart 
SYLVESTER: Fiscal conservatives have suggested cuts in food stamps, foreign aid, and preschool programs for low-income families, that private groups can and should provide for the needy  But David Beckman of Bread for the World, who used to work at the World Bank, says the private sector can't fill the gap 
DAVID BECKMAN, PRESIDENT, BREAD FOR THE WORLD: All the private charitable feeding in the country amounts to about six percent of the food that poor people get from the national programs  So if you slash food stamps, as the House Republicans are proposing to do, there is no way that churches and charities and charitable people can make up for that 
SYLVESTER: Tony Hall was a member of Congress for years  As part of the fast, he is urging his former colleagues to reconsider cuts 
TONY HALL, ALLIANCE TO END HUNGER: When you make decisions about people's lives, be careful  You don't cut the poorest of the poor, because they didn't get you here  They didn't cause this mess 
SYLVESTER: On Wednesday, members of Congress began signing up for the fast 
REP  BARBARA LEE (D), CALIFORNIA: Several members of Congress today will be joining you in this fast 
SYLVESTER: Now, Sheila Jackson Lee, Keith Ellison and Jim McGovern are among 28 congressional Democrats who have signed on so far to join the hunger fast, and they will be doing a relay, with each taking one day to fast and then passing on the fast to their colleagues 
Wallis and Hall, they're doing it a little differently  They're fasting all the way through Easter Sunday  But they say for them, this fight for the poor is larger than just the specific budget battle -- Wolf 
BLITZER: These are committed, committed people to try to help 
We're going back to Libya in just a few moments  Rebel forces, furious with NATO right now, the R-rated message they are sending through our own Ben Wedeman 
Context 2: Paper Info

Title: SLAS: Speed and Lane Advisory System for Highway Navigation
Publish Date: Unkown
Author List: Faizan Tariq, David Isele, John Baras, Sangjae Bae

Figure

Fig  1 Motivational Example With a slow moving vehicle ahead, the ego vehicle (in blue) may decide to either change lane to the fast moving lane (left) to minimize travel time or adjust its speed without changing lanes to preserve safety but it would be unwise for it to switch to the slow moving lane (right) as that would not benefit travel time or safety 
Fig  3  Simulation Setup Scenario Runner sets up the scenario for the CARLA Simulator, which then communicates with the SLAS and the Planning and Control ROS (Robot Operating System) nodes through the ROS bridge node 
Fig  4  Testing scenario with three lanes: lane 0 (left), lane 1 (center) and lane 2 (right) The expected motion of the ego vehicle, over the course of the simulation, is shown with numbered frames The right most lane (lane 3) is reserved for merging traffic so it is not utilized in our simulation 
Fig  5  Left: Travel time comparison Center: Lane choice (lateral position) comparison The center lines of lanes 0 (left), 1 (center) and 2 (right) have fixed lateral displacements of 0m, 3 5m and 7m respectively Right: Headway comparison With no leading vehicle, the headway is restricted by the visibility range of 50m 

abstract

This paper proposes a hierarchical autonomous vehicle navigation architecture, composed of a high-level speed and lane advisory system (SLAS) coupled with low-level trajectory generation and trajectory following modules  Specifically, we target a multi-lane highway driving scenario where an autonomous ego vehicle navigates in traffic 
We propose a novel receding horizon mixed-integer optimization based method for SLAS with the objective to minimize travel time while accounting for passenger comfort  We further incorporate various modifications in the proposed approach to improve the overall computational efficiency and achieve real-time performance 
We demonstrate the efficacy of the proposed approach in contrast to the existing methods, when applied in conjunction with state-of-the-art trajectory generation and trajectory following frameworks, in a CARLA simulation environment 

INTRODUCTION

Lane changing is considered to be one of the most risky driving behaviors since it is highly contingent upon multimodal trajectory predictions of neighboring vehicles and requires timely decision making   It is further influenced by a number of uncertainty factors such as road conditions, measurement accuracy, and a long tail of behavioral uncertainty of on-road agents 
However, if executed efficiently, lane changing coupled with speed adjustment can yield significant improvement in minimizing overall travel time while ensuring passenger comfort   To elaborate further, consider the scenario presented in Fig    Based on the predicted motion (shown in a lighter shade) of the neighboring vehicles (shown in orange), the ego vehicle (shown in blue) may decide to either change lane left in an attempt to minimize its travel time or slow down in the current lane to maintain safety 
However, it would be imprudent for the ego vehicle to risk changing lane right and consequently get stuck behind a slow moving vehicle even though there is presently a greater headway  This simple scenario highlights the importance of foresight and long planning-horizon in strategic decision making for autonomous vehicles 
Existing methods like MOBIL give us the ability to change lanes but behave greedily (prioritizing immediate rewards) oftentimes, which can lead to sub-optimal performance  It was shown in that the lane changing performance can be improved with an A inspired approach, but the formulation was limited to constant speed 
Such an approach is unable to assess the benefits of speed adjustment 1 University of Maryland, College Park, MD, USA  Email: {mftariq,baras}@umd edu  2 Honda Research Institute, San Jose, CA, USA  Email: {disele,sbae}@honda-ri com  Research supported by Honda Research Institute, USA   in minimizing overall travel time 
As will become apparent in Section IV, it may be necessary at times to sacrifice on shortterm benefits to gain long-term performance improvements  In such a scenario, an approach with speed adjustment coupled with long planning horizon has the foresight to deliver significantly better results  Moreover, the inclusion of speed adjustment in the decision making process inhibits the risk of incurring trajectory infeasibility as the environment conditions may prevent the ego vehicle from traveling at a constant reference speed and the low-level planner may be unable to handle such a discrepancy 
Therefore, in this work, we propose a low complexity receding horizon optimization based approach that outputs the lane change maneuvers coupled with speed adjustments for long planning horizons (> 15s) while guaranteeing safety  The long horizon strategic decision making gives ego vehicle the ability to proactively anticipate and handle challenging driving situations 
Literature review: In the literature, speed and lane changing decisions are generally considered from a motion planner's perspective , which allows for a simultaneous determination of target lanes and waypoints to perform the maneuver  The motion planning methods present in the literature can broadly be categorized into sampling-based, learning-based and optimization-based approaches 
In regards to the sampling-based approaches, single-query methods, in particular the different variants of RRT, are preferred over multi-query methods, like roadmap-based methods, due to the faster execution time and their ability to incorporate non-holonomic constraints   Even though these methods are able to incorporate safety guarantees by sampling feasible trajectories from a reachable safe set , the overall driving experience is often rather uncomfortable due to the concatenation of individual trajectories 
Moreover, the asymptotic optimality guarantees availed by arXiv:2303 00861v1 [cs RO] 1 Mar 2023 these methods do not help with real-world implementation in complex driving scenarios since they tend to have high sample complexity   In terms of the learning-based methods, the preferred approach seems to be the variations of Reinforcement Learning techniques applied in a simulated environment , , , ,  
These approaches, although seeming to work well in simulation, have concerns regarding real-world implementation due to the large amount of training data that they require, the exploration of unsafe behaviors during training, and a general inability to handle edge cases  They mainly utilize neural networks as function approximators which yields low computational complexity but also results in a lack of explainability and safety guarantees 
Lastly, the optimization-based approaches, especially the derivatives of optimal control methods, are abundant in the literature  In contrast to the potential-field based approaches that yield decent collision avoidance performance but are unable to accommodate vehicle dynamics, the optimal control methods , especially the derivatives of Model Predictive Control (MPC) approach , , , yield excellent collision avoidance performance while accommodating vehicle dynamics 
However, this performance comes at a cost of high computational complexity, arising mainly from the non-convex collision avoidance and the non-linear dynamics constraints  This, in turn, restricts the planning horizon to merely a few seconds  The key requirements for the algorithmic design of an autonomous vehicle include real-time operation, safety guarantees, optimality with respect to some metric(s), and accounting for the behavior variability of on-road agents 
Considering these requirements, we propose an optimization-based behavioral planning framework that enables autonomous vehicle maneuvering on multilane highways  While having the benefits of optimizationbased approaches, our method achieves a low computational complexity by employing a binary representation of the decoupled lane indicator dynamics in lieu of lateral dynamics, and utilizing algorithmic modifications to aid numerical computations 
Specifically, our method provides: • optimality with respect to travel time and comfort; • safety and feasibility guarantees; • real-time applicability for a long planning horizon; and • modularity in design, which enables the integration of external trajectory prediction modules  The proposed method fills in the research gap by meeting all the key algorithmic requirements while simultaneously gaining the foresight to make strategic decisions that yield long-term performance benefits, as verified in Section IV 
In this section, we present the algorithmic pipeline and formalize the road, observation and vehicle dynamics models that will be utilized in the subsequent sections 

Algorithmic Pipeline

Fig  illustrates the algorithmic pipeline of the proposed navigation architecture, in reference to the various existing   Algorithmic pipeline of the proposed navigation architecture  The raw sensory input data is processed by the Perception, and Simultaneous Localization and Mapping (SLAM) modules to place the autonomous vehicle relative to the various environmental entities in a unified frame of reference 
This information is then passed on to the navigation stack, composed of the behavioral planning, motion planning, and vehicle control modules  The output of the navigation module is passed down further in terms of actuation commands (brake, throttle and steering) to the actuators  algorithmic modules deployed on an autonomous vehicle 
The taxonomy of the various components of the navigation stack (highlighted by the dotted rectangle) is borrowed from   This pipeline essentially improves the pipeline introduced in by adding a speed advisory system  Our main focus is the development of the behavior planning module, highlighted as SLAS in Fig    SLAS outputs the target lane and reference speed which are utilized by the motion planning module to generate a reference trajectory for the ego vehicle 
The vehicle controllers compute the throttle and steering commands to track the trajectory accordingly  For the motion planning module, we adopt the Neural Networks integrated Model Predictive Control (NNMPC) due to its ability to accommodate the behaviors of neighboring vehicles in the trajectory generation process 
In our approach, we assume that the perception (of other vehicles) and the localization (of ego vehicle) are known without any uncertainty, for simplicity, but the modular architecture avails us the ability to integrate any perception or SLAM module in the overall framework  Throughout the manuscript, Z will denote the set of integers and R the set of real numbers 
For some a, c ∈ Z and a < c, we will write For some e, g ∈ R and e < g, we will write

Road Model

The physical road structure is modeled as a continuous multi-lane highway with negligible curvature and unidirectional traffic flow  The lanes on the highway are clearly demarcated and at any given time k, the number of available lanes for the vehicles to travel on is denoted by N l (k) while the road speed limit is denoted by V l  
Therefore, the set of lanes available for traveling at a given time instant k is denoted by   We work with the Frenet coordinate system where the distance along the road is denoted by the longitudinal displacement (s) and the distance perpendicular to the road is defined by the lateral displacement (d) 
Each lane is assigned a lane indicator variable l  The leftmost lane, with respect to the direction of traffic flow, is assigned a value of l = 0 while each subsequent lane is assigned an increasing integer value for l, as depicted in Fig   

Vehicle Model

Since we aim to have real-time computations for a long planning horizon (> 15s), we model the vehicle dynamics with a linearized decoupled dynamical system  For the highway driving scenario, where the road curvature is typically small, it is reasonable to assume a decoupling between the lateral and the longitudinal dynamics , especially for the behavior planning layer 
Therefore, we utilize a linear constant acceleration model for the longitudinal dynamics and abstract out the lateral dynamics with a lane indicator variable  For the lane change dynamics, we use a moving average filter coupled with a rounding function to model the time required by the ego vehicle to change lanes 
This is compactly represented as: where s 0 (k), v 0 (k), l 0 (k) and L(k) denote the ego vehicle's longitudinal displacement, speed, lane indicator and target lane, respectively, at time instant k; the subscript i indexes the vehicles on the road with 0 being reserved for the ego vehicle; T s denotes the discretization time step; and N corresponds to the number of time steps required to change lane 
The state (x 0 (k)) and control input (u 0 (k)) to the system at time instant k are defined as: where V m denotes the maximum speed of the ego vehicle 

Observation Model

For practical considerations, we restrict the ego vehicle's visibility range to the sensory perception limit, denoted by R v   Then, the set of vehicles in ego vehicle's visibility range at time instant k, represented by O(k), is defined as: where s i (k) corresponds to the longitudinal displacement of the observed vehicle 
Remark 1: For the multi-lane highway driving scenario, occlusion does not play a prominent role so we do not account for it in the existing formulation  However, the proposed framework can easily accommodate occlusion and measurement uncertainties since the receding horizon approach bases its decision on the most up-to-date information available at any given time, as demonstrated in  
In this section, we describe the prediction model to generate the predicted future trajectories of observed vehicles and present a discussion on the proposed receding horizon optimization-based behavioral planning module 

Trajectory Prediction

Reliable behavior and trajectory prediction of other traffic participants is crucial for safe maneuvering of autonomous vehicles  The algorithm proposed in Section III-B is able to incorporate any generic prediction module available in the literature as long as it can provide a deterministic predicted future trajectory for a given vehicle 
In this work, we formulate a low-complexity prediction model that highlights the flexibility and efficiency of our proposed approach  For an observed vehicle i ∈ O(k), the future speed profile is predicted using a piece-wise linear function while the lane profile is assumed to stay constant for the duration of the prediction horizon 
At a given time step k, the estimated acceleration (ā k i ) and the estimated speed (v k i ) parameters are obtained through linear regression with mean-squared error on the past o k i > 1 speed observations  Based on the estimated parameters, we predict the future speed and longitudinal displacement as follows:
Here, H a corresponds to the acceleration horizon while vk i (j) and ŝk i (j) respectively represent the predicted speed and longitudinal displacement for vehicle i, j time steps into the future starting from the current time instant k  Remark 2: Due to the modular nature of the proposed framework, the behavior planning module detailed in Section III-B can work with advanced maneuver-based (e g 
Markov Chain ) and interaction-based (e g  Social Generative Adversarial Networks ) trajectory prediction modules, allowing for interactive maneuvering behaviors 

Speed and Lane Advisory System

The goal of our behavior planning module, Speed and Lane Advisory System or in short, SLAS, is to determine a sequence of speed and lane change commands that would enable the ego vehicle to maximize its speed, thus minimizing the travel time, while accounting for driver comfort and abiding by its dynamical, actuator, and safety limits 
The output of this module is a relatively smooth speed and lane change profile which is then passed on to a motion planner  It is necessary to incorporate the dynamical and actuator limits in the behavioral planning module so as not to provide the motion planner with goals that are not reachable, and jeopardize the safety of the overall system as a result 
In the subsequent discussion, we provide a formulation of the optimization problem for SLAS; highlight the modifications necessary to improve the computational complexity; and, present safety and feasibility analysis  1) Optimization Problem with Integer Constraints: SLAS is posed as an optimization problem, with the objective to maximize speed while minimizing frequent lane changes and abrupt changes in speed 
The output of SLAS, at time instant k, is the control input u 0 (k + 1), as defined in   The optimization problem is formulated as follows: Objective Function: In the formulation above, the optimization variables are the ego vehicle's speed (v k (j)) and target lane (L k (j)), j step into the future, starting from time instant k 
Here, H corresponds to the planning horizon  The scalarization parameters γ 1 , γ 2 and γ 3 in the objective function account for a relative tradeoff between maximizing speed, minimizing lane changes and minimizing abrupt changes in speed respectively  Increasing γ 1 yields a more aggressive behavior with the priority placed on maximizing speed while γ 2 and γ 3 combine to place an emphasis on maximizing passenger comfort by reducing lane and speed changes respectively 
Dynamical Constraints: These constraints are put in place to ensure the dynamical feasibility of the solution  The constraints ( ), and serve to initialize the longitudinal displacement, speed and target lane respectively for the optimizer, based on the values observed at time instant k  The constraints and ( ) bound the ego vehicle's speed by the speed limit and the acceleration limits of the vehicle respectively
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❺ 微调顶绑带 微调顶绑带使其受力以减少额头压力 ❻ 瞳 距 调 节 在系统设置：“设置” ► “显示”界面中进行瞳距调节，点击“+”或“-”按钮可微调瞳距直至画面清晰 64mm 请勿 强行 掰动镜 筒，以 免造 成损坏 ！ 请注 意设 置使用 不合适 的瞳 距，可 能 会引起 视 觉重影 或 者眼睛 疲 劳。准 确 的瞳距 设 置有助 于 获得清 晰 的图像 并 减少眼睛 疲劳。 05 CN
产品部件详情说明 头盔状态指示灯 蓝灯常亮：开机进行中或工作状态 黄灯常亮：充电中，电量低于 98% 红灯常亮：充电中，电量低于 20% 绿灯常亮：充电完毕，电量大于 98% 或 充满 蓝灯闪烁：关机进行中 红灯闪烁：电量低于 20% 指示灯熄灭：休眠或关机 06 ① 电源键 开机：长按 2 秒 关机：长按 5 秒 复位：长按 10 秒 开机时，短按休眠 ② ③ ④ ⑤ 状态指示灯 贴脸泡棉 音量键 彩色透视摄像头 使用时请勿遮挡 ⑥ ⑦ ⑧ 顶部绑带 可拆卸 绑带旋钮 环境追踪摄像头 使用时请勿遮挡 ⑨ ⑩ ⑪ USB-C 接口 左 / 右喇叭 距离传感器 佩戴头盔后，系统自动唤醒 摘下头盔后，系统自动休眠 ⑫ ⑬ 眼球追踪摄像头 此功能仅 Pro 版支持 使用时请勿遮挡 面部追踪摄像头 此功能仅 Pro 版支持 使用时请勿遮挡 CN
手柄状态指示灯 熄灭：已连接或者关机 蓝灯常亮：固件升级模式 蓝灯闪烁：连接中 红蓝灯交替慢速闪烁：等待配对 ① ② 摇杆 菜单键 ③ Home 键 开机 : 短按关机 : 长按 6 秒退出应用 : 短按屏幕中心校正 : 长按 1 秒④ ⑤ ⑥ ⑦ 状态指示灯 抓握键 截屏键 扳机键 ⑧ ⑨ 电池盒 打开：拨动拨钮，电池盒弹出 安装：按压直至自动锁紧 追踪光环 使用时请勿遮挡 注：手柄挂绳可按图示将粗绳穿过细绳并锁紧在手柄尾端 07 CN
手柄硬件复位 如果手柄出现按 Home 键和任何按键均无反应或者头盔中虚拟手柄卡死不动的问题可拆装电池重新启动手柄。 近视用户配戴 本设备不具备近视调节功能，头盔可支持佩戴镜框宽度小于 150mm 的大多数标准眼镜。 操作说明 头控模式 未连接手柄的情况下，您可通过转动头部光标及点击头盔音量加减按键进行操作。 切换主控手柄射线 在主控菜单下，短按对应手柄的扳机键可以切换主控手柄的射线。 屏幕中心校正 戴着头盔直视前方，按住手柄 Home 键（或头控模式下头盔上的音量减键）1 秒以上，进行屏幕中心的校正将菜 单拉到当前视野朝向位置。 断开手柄 长按手柄 Home 键直至手柄状态指示灯红灯亮起并伴随振动产生时即可松手，此时手柄关机并断开与头盔的连接。 您无需刻意进行手柄关机操作，在以下状态下手柄会自动关机省电： •头盔进入深度休眠时（摘下头盔后一段时间） •头盔手柄管理界面解绑手柄时 •头盔关机时 添加新手柄 如需添加新手柄（头盔最多可同时连接一对手柄，即左右手柄各一只），或解绑手柄后再次连接 , 可进入“设置” “手 柄”，点击“配对”，同时按住手柄 Home 键和扳机键直至手柄状态指示灯红蓝交替闪烁时即可松开，然后根据 头盔画面提示操作。 ► 休眠 / 唤醒 方式一：摘下头盔一段时间后，系统自动休眠；戴上头盔时，系统自动唤醒。 方式二：短按头盔电源键也可以进行休眠或唤醒操作。 硬件复位 头盔硬件复位 如果头盔出现短按头盔电源键没有反应或头盔的画面卡死等问题，可以长按头盔电源键 10 秒以上重新启动头盔。 08 CN
安装眼镜支架 安装遮光鼻托 如您存在眼镜摩擦光学镜片或者压迫鼻梁的问题，请按照图示安装眼镜支架以增加间隔空间。 您可根据佩戴的舒适度选择是否安装。 如您感觉鼻子处漏光影响体验，请按照图示安装遮光鼻托配件。 由于眼睛空间密闭可能加剧起雾及出汗问题，您可根据喜好选择是否安装。 ❶ 摘下贴脸泡棉 ❷ 将眼镜支架按照图示安装在产品上 ❸ 将贴脸泡棉按照图示安装眼镜支架上 ❶ 摘下贴脸泡棉 ❸ 安装贴脸泡棉❷ 将遮光鼻托按照图示方式安装在贴脸泡棉上 注：按照图示拆卸眼镜支架 09 CN
更换贴脸泡棉 贴脸泡棉多次清洁和长时间使用后会变色和质地变软，您可酌情更换新泡棉。 更换顶绑带 摘下贴脸泡棉 ❸ 安装贴脸泡棉 按照图示捏住顶绑带金属扣，往下压到底然后抽出 ❷ •购买优质热门应用 •畅 聊 社 区， 与 众 多 PICO 玩 家 一起探索 VR 世界 •管理设备更便捷 •参与丰富互动活动 •更多精彩内容等你来发现 ❶ 微 信公 众 号：PICO VR抖音：PICO官 方 旗 舰 店哔 哩 哔 哩：PICO-VR官 方微 博：PICO-VR ❶ ❷ 10 CN
In The Box: VR Headset / 2 Controllers / 4 1 5V AA Alkaline Batteries / Glasses Spacer / Nose Pad / 2 Controller Lan- yards / USB-C Power Adapter / USB-C to C 2 0 Data Cable / Quick Guide / User Guide / Safety and WarrantyGuide Important Health & Safety Notes • This product is designed and intended to be used in an open and safe indoor area, free of anytripping or slipping hazards  To avoid accidents, remain conscious to the potential confines ofyour physical area and respect the boundary of your virtual area whenever you see it  Be sure towear the lanyards when using the Controllers  Make sure that there is enough space around yourhead and body (at least 2 meters by 2 meters) to stretch your arms to avoid damage or injury toyourself, others, and your surroundings  • This product is not recommended for children aged 12 and under  It is recommended to keep headsets,controllers and accessories out of the reach of children  Teenagers aged 13 and over must use it underadult supervision to avoid accidents  • This product is designed to accommodate most prescription glasses  Make sure to wear the VR Headsetin a manner in which the VR Headset lenses do not rub or impair your prescription lenses  • Prolonged use may cause dizziness or eye fatigue  It is recommended to take a break every 30 minutes Try relieving your eyestrain by looking at distant objects  If you feel any discomfort, stop using the prod- uct immediately  If the discomfort persists, seek medical advice • Do not expose the optical lenses to direct sunlight or other strong light sources  Exposure to directsunlight may cause permanent yellow spot damage on the screen  Screen damage caused by sunlightexposure or other strong sources of light is not covered by the warranty  • This product supports interpupillary distance (IPD) adjustment in system settings  When adjusting,please be aware that with the minimum IPD, it may touch the bridge of the nose  You can adjust the IPDaccording to your actual interpupillary distance in "Settings"►"Display"  Please note that using inap- propriate IPD may increase the risk of discomfort  • This product has an “Eye Protection Mode”, certified by TÜV Rheinland (Germany), which can protectyour eyes by reducing blue light in the three color channels using software algorithms  The screen ap- pears yellowish in this mode and you can turn this feature on/off in "Settings"►"Display"►"Color"►“- Eye Protection”  • Protect optical lenses during use and storage to prevent damage, such as scratches or exposure tostrong light or direct sunlight  * Product and packaging are updated regularly, and the functions and contents of the standalone headset may be upgraded in the future Therefore, the content, appearance and functionality listed in this manual and product packaging are subject to change and may notreflect the final product  These instructions are for reference only  * Carefully read this user guide before using the product and share this information with any other users, as it contains important safetyinformation  Keep the user guide as reference for the future  11 EN
6 Degrees of Freedom VR The device can track your translational and rotational movements in all directions (up/down, left/right,forward/backward, pitch, roll, and yaw)  Your movements in the real world will be captured and translatedto what you see in the virtual world when using the appropriate content  Ensure a safe environment before you start your VR experience  1  Clear a safe indoor area of at least 2 meters by 2 meters  Keep the room bright, avoid spaces with main- ly single-colored walls, glass, mirrors, moving pictures or other similar objects  2  Remove the protective film that covers the headset front cameras  Wear the lanyards connected to theControllers  3  Set up your environment by following instructions on the VR Headset screen  Install Batteries ❶Pull the tab to remove the insulating paper  Quick Guide 2 m 2m This product can not guarantee your safety with guardian system, you will need to always pay attention to the surrounding safety  * Note: 1 5V AA alkaline batteries should be used



ground_truth: The sticking point in the political showdown over the budget is how much spending to cut.

prompt_front: Now, answer the following question based on the text below, only give me the answer and do not output any other words.

Question: What are the benefits of using binary variables in the SLAS formulation?

Read the following text and answer briefly.

Context 2: 
The ego vehicle's speed is then used to calculate the projected longitudinal displacement in   The target lane values at any planning step (j) are restricted to the set of reachable values by ( ), ( ) and   Here, restricts the target lane to the set of available lanes (L(k)), ensures that the lane change, if needed, is made to the adjacent lane only and (17) models the time steps (N ) required for a lane change 
The flooring function can easily be transformed into a couple of linear constraints by the introduction of an auxiliary integer variable, as shown in the Appendix  Finally, l k (j) is merely the internal representation of the lane the ego vehicle is projected to travel on at planning step j  Safety Constraint: The safety constraint ensures that the ego vehicle maintains a minimum safe distance (L s i (j)) to the nearest vehicle i, in its projected lane of travel (l k (j)), at planning instant j 
We borrow the definition of this safe distance from , where the authors provide a formalization, based on the clause from Vienna Convention on Road Traffic that states that "A vehicle [   ] shall keep at a sufficient distance [   ] to avoid collision if the vehicle in front should suddenly slow down or stop "
Furthermore, the absolute value constraint can be decomposed into linear constraints by the application of big-M method and the introduction of an auxiliary variable, as shown in the Appendix  Remark 3: The proposed formulation can accommodate arbitrary number of lanes at any given time instant k  This means that if at any given time, the number of available lanes for traveling either increases or decreases, the proposed formulation will still continue to hold 
This is an important consideration since many a times on highways, some lanes are blocked due to various unanticipated situations such as road accidents, roadwork, narrowing of road etc  2) Computational Complexity Reduction: This section details the optimization problem reformulation with binary variables, optimization warm start technique and lazy constraint implementation, all of which combine to improve the computational complexity of our SLAS module 
Binary Variables: The proposed formulation in Section III-B has relatively high computation complexity (computation time of ∼ 2s in the worst case scenario -slow moving traffic blocking all the lanes) due to the integer decision variables yielding a mixed-integer optimization problem   To circumvent the computational overload, we reformulate the problem with binary variables that replace the integer variables, as follows:
where the Lk (i, j) represents the modified target lane variable, indexed by the lane (i) as well as the planning step (j) and Lk (a, b) = 1 represents the choice of lane a ∈ L as the target lane at planning step b ∈ Z   Then, some of the constraints from the SLAS formulation in Section III-B are modified as follows:
Here, initializes the target lane, (21) restricts the target lane at any planning step to the set of available lanes, restricts the lane change between consecutive planning steps to the adjacent lanes, and ( ) represents the augmented safety constraint  The implication ( =⇒ ) in ( ) can easily be transformed into a linear constraint (see Appendix) 
The augmented minimum safety distance ( Ls i (j)) incorporates the time required to execute the lane change maneuver (N ) from ( ) into the following unified safety constraint: where L l is the width of the lanes (see Fig  ), δ(k) is the signed lateral deviation of the ego vehicle from the previous target lane's boundary at time step k, and γ d (δ k (j)) is the dynamic cost of deviation from the previous target lane (L(k − 1)) 
Moreover, in the cost function , we take L k (0) = L(k − 1)  These costs are introduced to prevent the swerving (canceling of lane switch before completion) behavior, unless absolutely necessary (for safety purposes)  Remark 4: Since the ego vehicle is considered to have changed lane once it crosses a lane boundary, the deviation δ k (j) is considered from the lane boundary instead of the center of the target lane to maintain the continuity of γ d (δ k (j)) with respect to the lateral displacement of the ego vehicle 
Specifically, δ k (j) > 0 if the ego vehicle has crossed the previous target lane boundary and 0 otherwise  This is an important consideration since a discontinuity in γ d (δ k (j)), upon completion of lane change, may lead to infeasibility  Remark 5: The swerving behavior is suppressed but not completely eliminated with a hard constraint since such a behavior is necessary at times to react to the environment's unpredictability 
This reactive strategy, which is a distinctive feature of our approach, avails the algorithm the ability to proactively 'change its mind' in case something unanticipated happens in the environment that can jeopardize safety  Optimization Warm Start: To aid the optimizer in finding an initially feasible solution, we provide the solution from the previous time step as a reference 
Formally, This doesn't imply that the solution from time step k − 1 will hold exactly at time step k, owing to the unmodeled disturbances, but providing this reference aids the optimizer in finding an initially feasible solution in the vicinity of the reference solution  This observation is rooted in the premise that the solution for the long planning horizon is not expected to change significantly between time steps, given the sampling time is not too large, and the predicted behavior of on-road agents does not alter significantly 
It is also worth pointing out that the priority here is quickly finding a feasible solution that obeys the safety constraints and actuator limits, and recursively improving it rather than excessively iterating to reach at a global optimum  In our experiments, it was observed that a suboptimal solution was qualitatively not significantly different from the optimal one 
Therefore, we utilize the cutting planes method for optimization , which first looks for a feasible solution, using our provided reference, and then recursively updates it until either the globally minimal solution is found or the time limit is reached  Lazy Constraints: To further enhance the computational efficiency, we introduce a lazy implementation of the lane changing constraints  
It was observed in our experiments that a feasible solution without the lane changing constraints ( ) can be found several order of magnitude (∼ 10×) quicker than if we include these constraints so we decided to have a lazy implementation for them  With a lazy implementation , the solver finds a set of feasible solutions without the inclusion of these constraints and then determines the feasibility of those solutions from the reduced problem with respect to the lazy constraints 
3) Feasibility: By an argument similar to the one presented in , it is a relatively straightforward proof for recursive feasibility of the problem, i e  the optimization problem will continue to stay feasible, if initially feasible, with the trivial solution being matching the speed of the leading vehicle and not changing lanes 
In this section, we detail our experimental setup, demonstrate the performance of SLAS, and report a qualitative as well as a quantitative comparative analysis  The baselines in our comparative analysis are set to: Extended-Astar (EA ) , MOBIL , and no lane-change model (No-Change) 

Experimental Setup

The implementation setup, depicted in Fig  , is composed of the CARLA simulator (Version 0 9 11) , SLAS module (Section III-B), and the planner and controller module   To solve the optimization problem for SLAS, we use Gurobi Optimizer (Version 9 1 1)   The simulations are performed on a computer equipped with an Intel Xeon(R) CPU E5-2643 v4 @ 3 40GHz × 12 and NVIDIA Titan XP, running Ubuntu 20 04 LTS 
On average, the time required for each optimization step is ∼ 0 096s, while the maximum time limit for the optimizer is set to 0 2s, indicating the strong potential for real-time applicability 

Case Study

Figure illustrates the test case scenario for our comparative analysis  The scenario is composed of a highway segment with four lanes and the rightmost lane reserved for merging vehicles  The ego vehicle is initialized to follow a slow moving vehicle in lane 1 and has even slower moving traffic to its right in lane 2  Thus, the only option for it, in order to minimize travel time, is to switch left to lane 0 with faster moving traffic and greater headway 
Once it moves to lane 0, and overtakes the slow moving vehicle in lane 1, it has two options: either to keep traveling in lane 0 without making any lane change decisions until getting close to the lead vehicle or proactively exploiting the gap in lane 2 to switch to lane 3 in anticipation of traffic buildup in lanes 1 and 2  A strategic decision maker with foresight will choose to take the later option and make the decision proactively for a greater overall benefit 
The evaluation metrics for the comparative analysis include: travel time, lateral displacement, headway and distance to the closest vehicle  As for the simulation parameters, the simulation step size is set to 0 05s (simulation frequency of 20Hz); the velocities of vehicles in lanes 0, 1 and 2 are set to 8, 5 and 2 m/s respectively while the speed limit V l is set to 15m/s; the length of the highway patch is set to 350m while the width between the lanes is set to 3 5m; and the sensor visibility range is set to R v = 50m 
The parameters for SLAS are set as follows: T s = 0 4s, H = 40, N = 3, A min = −5m/s 2 , A max = 3 5m/s 2 , γ 1 = 1, γ 2 = 0 1 and γ 3 = 0 01  The values of these parameters can be tuned to yield an aggressive or defensive behavior of the algorithm  1) Travel Time: The left plot in Fig  depicts the travel time as a function of longitudinal displacement for the four algorithms 
As seen in the plot, our method (SLAS) maintains a lower overall travel time as compared to the other methods  Quantitatively speaking, SLAS outperforms EA , MOBIL and No-change methods by 12 72%, 23 52% and 54 34% respectively in terms of the time required to complete the simulation scenario  This shows that our method's foresight compensates for its apparent conservativeness arising from the need to preserve passenger comfort 
2) Lateral Displacement: To identify the differences in lane changing behaviors between the four approaches, the relationship between lateral and longitudinal displacements over the course of the simulation is highlighted in the center plot of Fig    In the plot, the lateral displacement of 0 corresponds to the center of lane 0 while the center of each following lane is 3 5m away 
Comparing the performance of the four algorithms, we see SLAS and EA showing relatively similar performances, resulting from proactive decision making  In contrast, since MOBIL only assesses the advantage of switching to the adjacent lanes, it is unable to see the benefit of proactively switching to lane 2  This explains why EA and SLAS start outperforming MOBIL in terms of travel time (left plot) at around the 130 [m] mark for longitudinal displacement 
As for a direct comparison between SLAS and EA , the benefits of having speed advisory system become apparent in this center plot  Due to speed control, SLAS is able to constantly maintain a greater headway (right plot) without having to brake significantly upon getting too close to the lead vehicle  This results in a smooth lateral displacement profile which allows the vehicle to change lanes with minimal jerk (quantitative analysis to follow in Section IV-C) and deliver better overall timing performance (left plot) 
3) Headway: The right plot in Fig  shows the headway maintained by the ego vehicle over the course of the simulation  In accordance with our prior discussion, MOBIL cruises behind the front vehicle, maintaining a relatively low headway until a sufficient space in the adjacent lane is found to perform the lane-change maneuver 
On the other hand, EA and SLAS show a comparable headway trajectory, however, SLAS maintains a greater headway throughout and achieves the maximum headway prior to EA   Quantitatively, SLAS maintains on average 9 43%, 36 57% and 113 17% more headway than the EA , MOBIL and No-change approaches respectively 
This strong performance by SLAS can be attributed to its incorporation of safety guarantees coupled with its consideration for passenger comfort  4) Distance to closest vehicle: Finally, we compare the distance that ego vehicle maintains from the closest vehicle throughout the simulation  On average, SLAS maintains 9 28%, 32 01%, and 22 84% more distance in comparison to EA , MOBIL and No-change approaches respectively 
These numbers are a testament to the strength of our approach resulting from consideration of long planning horizon coupled with speed control 

Monte Carlo Simulations

To demonstrate the long-term performance of the three approaches (SLAS, EA and MOBIL), we run a series of Monte Carlo simulations on scenarios with randomized initial positions (within a range of 8m) and velocities (within    ranges of 8, 5 and 2 m/s assigned to each of the three lanes randomly) of traffic participants 
The result from 50 simulations is presented in Table   In this table, the columns represent the different evaluation metrics, the rows identify the three algorithms, and the values highlighted in green represent the best result with respect to each evaluation metric  The evaluation metrics, going from left to right in the table, are completion time (s), brake (R [−1,0] ), brake jerk (R [−1,0] ), throttle (R [0,1] ), throttle jerk (R [0,1] ), angular acceleration ( • /s 2 ) and angular jerk ( • /s 3 ) 
Apart from completion time, the remaining metrics, based on the commands passed to the vehicular actuators (Fig  ), are used to model passenger comfort  In terms of average performance, SLAS greatly outperforms the other methods when it comes to passenger comfort since it explicitly accounts for comfort in the formulation 
However, it does so at a cost of slightly reduced performance in regards to travel time, when compared to EA , since SLAS tries to strike a balance between minimizing travel time and maximizing passenger comfort  SLAS also secures the lowest standard deviation, for each of the evaluation metrics, when compared to the other methods, which points to the consistency in its long-term performance 

CONCLUSION

We propose a novel behavior planning module for the multi-lane highway maneuvering scenario, that outputs strategic target lane and reference speed commands, and incorporate it with a state-of-the-art motion planning and control framework  We formulate the approach as a receding horizon mixed integer optimization with the goal to minimize travel time while accounting for passenger comfort for a long planning horizon 
In order to reduce the computational overload, we reformulate the problem by replacing integer variables with binary ones and further incorporate various modifications to aid numerical computations  We also carry out a detailed comparative analysis to demonstrate the performance of our approach on the CARLA simulator 
Our future work includes incorporating various delays and uncertainty measures in the perception, localization and prediction modules to evaluate the robustness properties of our approach 

Flooring Constraint

For y ∈ Z and x ∈ R, the constraint y = x can be represented by the following linear constraints: y ≤ x, y + 1 ≥ x + where > 0 accounts for the feasibility tolerance  where M 0 (big-M) and > 0 accounts for numerical errors (chosen to be 0 1 in our implementations) 

Absolute Value Constraint

For ∆s, L s ∈ R, the constraint |∆s| − L s ≥ 0 can be represented as: This can further be generalized, as done in our implementation, to have different forward and rear safety margins as: ∆s ≥ L f s ∨ ∆s ≤ −L r s where L f s and L r s are forward and rear safety margins respectively  This can be represented with the following linear constraints:
s ≥ 0 where M 0 (big-M) and c ∈ {0, 1} is responsible for making a choice between the two constraints 



ground_truth: Reduced computational complexity.

prompt_front: Now, answer the following question based on the text below, only give me the answer and do not output any other words.

Question: What may happen if the VR headset lenses are exposed to sunlight or strong light?

Read the following text and answer briefly.

Context 3: Slide the toggle according to arrow direction toopen the battery case  12 EN
Power on the Controller ❷ First Start: The Controller will start automaticallyafter removing the insulating paper  Others: Short press the Home button for 1second until the status indicator flashes blue Power on the VR Headset ❸ Long press the Power button for 2 seconds untilthe status indicator turns blue Wear Your Headset for a Comfortable Fit and View ❹ Adjust the strap dial to turn the strap so that the back of your head rests on the padding  Fine-tune thelength and position of the strap to give a clear view  * Note: You can use this product with prescription glasses or lenses insert  13 EN
Fine-tune the Top Strap ❺ Fine-tune the head strap to reduce pressure on the forehead  Interpupillary Distance (IPD) Adjustment ❻ In System Setting, go to “Setting” ► “Display” to adjust IPD, tap “+” or “-” button to slightly adjust IPDuntil the picture is clear  14 64mm Please note that inappropriate IPD setting may cause ghosting or eyestrain Accurate IPD setting helps you get a clear imaging and ease eyestrain  EN
Product Details VR Headset Status Indicator Legend Blue: Powered on with battery over 20% Yellow: Charging: Battery is less than 98% Red: Charging: Battery is less than 20% Green: Charging: Battery is more than 98% or charge complete Blue flashing: Shutting down Red flashing: Battery is less than 20% Off: Sleeping or Powered off Power Power on: Long press for 2 seconds Power off: Long press for 5 seconds Hardware reset: Long press for 10 seconds Short press to enter sleep or wake up Status Indicator Face Cushion Volume ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ RGB See Through Camera Do not block during use  Top Strap Removable Strap Dial Tracking Cameras Do not block during use  ⑨ ⑩ ⑪ USB-C Interface Left/Right Speaker Proximity Sensor The system wakes upwhen the VR headset isput on, sleeps when VRheadset is taken off  ⑫ ⑬ Eye Tracking Cameras Pro version only  Do not block during use  Face Tracking Camera Pro version only  Do not block during use  15 EN
Controller Status Indicator Legend Off: Connected or Powered off Blue: Firmware updating in progress Blue flashing: Searching for connection Red and blue flashing alternately: Pairing in progress 16 Joystick Menu ③ ① ② Home Power on: Short pressPower off: Long press for 6 secondsReturn home screen: Short pressScreen recentering: Press for 1 secondStatus Indicator Grip Capture Trigger ④ ⑤ ⑥ ⑦ ⑧ ⑨ Battery Case Open: Slide down the toggle andpop up the battery case  Lock: Push the battery case to lock  Tracking Ring Do not block during use  * Note: Pass the Controller Lanyardthrough the string as shown andlock at the end of the Controller EN
Operating Instructions Headset Control Mode If the Controller is not connected, you can interact with the home screen by moving your head to directthe crosshairs over your intended selection and clicking the Volume Up/Down button on the VR Headset  Switch the pointer of the master Controller In the home screen, short press the Trigger of the corresponding Controller to switch the pointer of themaster Controller  Screen re-centering Wear the VR Headset and look straight ahead, press and hold the Home button of the Controller or VRHeadset ( or the Volume Down button of the VR Headset in head control mode) for more than 1 second tore-center the screen  Disconnect the Controller Press and hold the Home button until the status indicator turns red and the Controller vibrates Controllers will automatically shut down to save power in the following cases:When the VR Headset enters deep sleep (a while after the VR Headset is taken off)When the Controller is unpairedWhen the VR Headset is powered off Add a new Controller If you need to add a new Controller (the VR Headset can only connect one left Controller and one rightController) or reconnect with an unpaired Controller  Go to “Settings” ► “Controller”, click on “Pair” Press and hold the Home button and the Trigger of the Controller at the same time until the red and bluelights of the Controller flashing alternately, and then follow the instructions on the VR Headset screen  Sleep / Wake up Option 1 (Proximity Sensor) Take off VR Headset for automatic sleeping: wear the VR Headset for automat- ic waking up  Option 2 (POWER Button) Press the Power button of the VR Headset for manual sleeping or waking up  Hardware reset VR Headset reset If the visual in the VR Headset freezes, or the VR Headset does not respond after short press the Powerbutton, you can press the Power button of the VR Headset for more than 10 seconds to reboot the VRHeadset  Controller reset If the virtual Controller, the Home button or any buttons of the Controller doesn\'t respond, remove andreinstall the battery case to restart the Controller  The VR Headset Adjustment This device has no myopia adjustment function  The VR Headset allows wearing most standard glasseswith a frame width of less than 150mm  to install Glasses Spacer to increase the space  You can install or not according to your situation  17 EN
Install Glasses Spacer Install Nose Pad If you have glasses collision with headset lens or pressure on the bridge of nose, please follow the pictureto install Glasses Spacer to increase the space  You can install or not according to your situation  If you feel light leaking from your nose, please follow the picture to install Nose Pad to block the light You can consider having it installed at your own discretion  Disassemble the Face Cushion  Install the Glasses Spacer on the Headset  ❸ ❶ ❷ Install the Face Cushion on the Glasses Spacer  Disassemble the Face Cushion  Install the Nose Pad on the Face Cushion  ❶ ❷ Install the Face Cushion on the Headset  ❸ * Note: Disassemble the Glasses Spacer 18 EN
Replace Face Cushion The Face Cushion will have the following phenomena such as color change, surface fluff, soft texture afterlong-term use and repeated cleaning  You can replace a new Face Cushion as needed  Replace Top Strap ❶ ❷ Disassemble the Face Cushion  Pinch the metal buckle of the top strap asshown, press it down and pull it out Install the Face Cushion on  ❸ ❷ ❶ • Purchase high-quality and trending apps • Join PICO Community and explore the VR worldwith other PICO players• Manage your device with ease • Engage in diverse and interactive activities • More exciting features waiting for you 19 EN
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ground_truth: Exposure to sunlight or strong light may cause permanent yellow spot damage on the screen.