nyuuzyou/kompy huggingface dataset:
Using the Command Line | 21

Manual Pages
Historically, the Unix manual has been available online, meaning directly on the
machine. To get the documentation for any command, you would run the program
man
followed by the command you wanted the documentation for. These man pages
have been formatted in a typesetting language called
troff
. As a result, when you are
reading the man page, it looks like it was formatted to be printed, which is essentially
true. If you need help finding the relevant command-line parameters to get the
behavior you are looking for, you can use the man page to get the details. The man
pages will also provide you with associated commands and information.
The Unix manual was divided into sections, as follows:
• General Commands
• System Calls
• Library Functions
• Special Files
• File Formats
• Games and Screensavers
• Miscellanea
• System Administration Commands and Daemons
When the same keyword applies in several areas, such as
open
, you just specify which
section you want. If you want the system call open, you use the command
man 2
open
. If you also need to know relevant commands, you can use the command
apro‐
pos
, as in
apropos open
. You will get a list of all the relevant manual entries.
Interestingly, AT&T Unix diverged a bit from BSD Unix. This has resulted in some
command-line parameter variations, depending on which Unix derivation you may
have begun with. For more detailed process listings, including all of the processes
belonging to all users (since without specifying, you get only processes belonging to
your user), you might use either
ps -ea
or
ps aux
. Either will provide the complete list,
though there will be differences in the details provided.
The thing about using
ps
is that it’s static: you run it once and get the list of processes.
Another program can be used to watch the process list change in near-real time.
While it’s possible to also get statistics like memory and processor usage from
ps
, with
top
, you don’t have to ask for it. Running
top
will give you the list of processes,
refreshed at regular intervals. You can see sample output in
Example 1-4
.
| Chapter 1: Foundations of Kali Linux

Example 1-4. Using top for process listings
top - 20:14:23 up 3 days, 49 min, 2 users, load average: 0.00, 0.00, 0.00
Tasks: 139 total, 1 running, 138 sleeping, 0 stopped, 0 zombie
%Cpu(s): 0.3 us, 0.2 sy, 0.0 ni, 99.5 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem : 4050260 total, 2722564 free, 597428 used, 730268 buff/cache
KiB Swap: 4192252 total, 4192252 free, 0 used. 3186224 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
6995 root 20 0 105384 6928 5932 S 0.3 0.2 0:00.11 sshd
7050 root 20 0 47168 3776 3160 R 0.3 0.1 0:00.09 top
1 root 20 0 154048 8156 6096 S 0.0 0.2 0:02.45 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.06 kthreadd
4 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:+
5 root 20 0 0 0 0 S 0.0 0.0 0:01.20 kworker/u4+
6 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 mm_percpu_+
7 root 20 0 0 0 0 S 0.0 0.0 0:00.20 ksoftirqd/0
8 root 20 0 0 0 0 S 0.0 0.0 0:38.25 rcu_sched
9 root 20 0 0 0 0 S 0.0 0.0 0:00.00 rcu_bh
In addition to providing a list of processes, the amount of memory they are using, the
percentage of CPU being used, as well as other specifics,
top
shows details about the
running system, which you will see at the top. Each time the display refreshes, the
process list will rearrange, indicating which processes are consuming the most
resources at the top. As you will note,
top
itself consumes some amount of resources,
and you will often see it near the top of the process list. One of the important fields
that you will see not only in
top
but also in
ps
is the PID. In addition to providing a
way of clearly identifying one process from another, particularly when the name of
the process is the same, it also provides a way of sending messages to the process.
You will find two commands invaluable when you are managing processes. They are
closely related, performing the same function, though offering slightly different capa‐
bilities. The first command is
kill
, which, perhaps unsurprisingly, can kill a running
process. More specifically, it sends a signal to the process. The operating system will
interact with processes by sending signals to them. Signals are one means of interpro‐
cess communication (IPC). The default signal for
kill
is the TERM signal (SIG‐
TERM), which means
terminate
, but if you specify a different signal,
kill
will send that
signal instead. To send a different signal, you issue
kill -# pid
, where # indicates the
number that equates to the signal you intend to send, and
pid
is the process identifi‐
cation number that you can find from using either
ps
or
top
.
Signals
The signals for a system are provided in a C header file. The easiest way to get a list‐
ing of all the signals with their numeric value as well as the mnemonic identifier for
the signal is to run
kill -l
, as you can see here:
Learning Kali Linux - bet 209

Bluetooth Testing
Bluetooth is a common protocol that is used to connect peripherals and other I/O
devices to a system. This system can be a desktop computer, a laptop, or even a smart‐
phone. Peripherals have a wide variety of capabilities that are defined by profiles.
Bluetooth uses radio transmission to communicate, with a frequency range that is
close to one of the ranges used by WiFi. Bluetooth is a relatively low-power transmis‐
sion medium; commonly, you have a range of up to about 30 feet. Bluetooth devices
are required to pair with one another before any information can be passed from one
device to another. Depending on the complexity of the device, the pairing may be as
simple as identifying the peripheral after putting it into pairing mode or it may
require confirming a PIN on either side.
If you have a Bluetooth radio in your computer, you can use it to perform testing with
the tools provided by Kali. You may wonder why Bluetooth is strictly relevant when it
comes to security testing. With so many devices, offering so many services, including
file transmission, sensitive company information could be available to attackers if the
Bluetooth device isn’t appropriately locked down. Because of the potential sensitivity
of what a Bluetooth device can provide access to as well as the potential for acquiring
information (imagine an attacker getting remote access to a keyboard, for instance, as
a user starts to type a username and password imagining the keyboard is still connec‐
ted to their system), Bluetooth devices will commonly be undiscoverable unless
specifically put into a state where they are discoverable.
The industrial, scientific, and medical (ISM) radio band is a set of
frequencies that have been allocated for use by a range of devices.
This includes microwave ovens, which is the appliance that trig‐
gered the allocation to begin with, in 1947. The 2.4GHz–2.5GHz
range is used by microwaves, WiFi, Bluetooth, and other applica‐
tions.
Scanning
While you may not get much in the way of devices available, a few tools can be used
to scan for local Bluetooth devices. Keep in mind that this is something you need to
be in close proximity to do. If the building you are working in is large, you will need
to do a lot of scans from numerous locations in the building. Don’t assume that pick‐
ing even a central location will give you meaningful results.
The first tool is provided by the
bluez-tools
package. It isn’t specifically related to
security testing but instead is a utility that is used to manage Bluetooth devices. The
program
hciutil
uses the human-computer interaction interface in your system. In my
case, it’s a Bluetooth dongle that is connected via USB. To identify Bluetooth devices
| Chapter 7: Wireless Security Testing

"AVCTP"
(
0x0017
)
uint16: 0x0104
Profile Descriptor List:
"AV Remote"
(
0x110e
)
Version: 0x0103
Service Name: Advanced Audio
Service RecHandle: 0x10006
Service Class ID List:
"Audio Source"
(
0x110a
)
Protocol Descriptor List:
"L2CAP"
(
0x0100
)
PSM: 25
"AVDTP"
(
0x0019
)
uint16: 0x0102
Profile Descriptor List:
"Advanced Audio"
(
0x110d
)
Version: 0x0102
Unsurprisingly, we can see that the MiBox supports the AV Remote Control Target. It
also supports Advanced Audio, as you might expect. Each of these profiles has a set of
parameters that are necessary for any program to know about. This includes the pro‐
tocol descriptor list.
Service Identification - Learning Kali Linux

Example 7-18. Using hcitool to get features
root@savagewood:/# hcitool info 00:9E:C8:93:48:C9
Requesting information ...
BD Address: 00:9E:C8:93:48:C9
OUI Company: Xiaomi Communications Co Ltd
(
00-9E-C8
)
Device Name: MIBOX3
LMP Version: 4.1
(
0x7
)
LMP Subversion: 0x6119
Manufacturer: Broadcom Corporation
(
15
)
Features page 0: 0xbf 0xfe 0xcf 0xfe 0xdb 0xff 0x7b 0x87
<3-slot packets> <5-slot packets>
2
Mbps>
3
Mbps>
<3-slot EDR ACL>
<5-slot EDR ACL>
2
Mbps>
3
Mbps> <3-slot EDR eSCO>
Features page 1: 0x0f 0x00 0x00 0x00 0x00 0x00 0x00 0x00
Features page 2: 0x7f 0x0b 0x00 0x00 0x00 0x00 0x00 0x00
What we know from this output is that the MiBox supports synchronous connection-
oriented (SCO) communication. Included in this is the ability to use one, two, and
three slots for communication (HV1, HV2, and HV3). We also know that it supports
Enhanced Data Rate (EDR) for faster transmission speeds. This would be necessary
for any audio streaming that would need more bandwidth than transmitting some‐
thing like a single scan code maybe a few times a second, as would be the case for
keyboards. We can use the information we’ve acquired here to make inferences, but
it’s still helpful to know what profiles the device supports.
To get the profiles, we’re going to turn to using the service discovery protocol (SDP).
We’ll use
sdptool
to get the list of profiles that are supported. With a device as com‐
plex as a MiBox, we’re likely to get several profiles back. Keep in mind that three
dozen profiles are defined at the moment by Bluetooth.
Example 7-19
shows the use
of
sdptool
to browse the MAC address we acquired earlier. You’ll see only a subset of
the entire output here, just to give you a sense of what is available.
Example 7-19. sdptool providing a list of profiles
root@savagewood:/# sdptool browse 00:9E:C8:93:48:C9
Browsing 00:9E:C8:93:48:C9 ...
Service RecHandle: 0x10000
Tarmoq uzellarini adreslash

|
Tarmoq uzellarini adreslash
|
Sana | 31.01.2024 | Hajmi | 2,22 Kb. | | #149292 |
Bog'liq Lokal tarmoqlarni loyihalash va tashkil etish. Tarmoq uzellarini-fayllar.org
| xmlns:w="urn:schemas-microsoft-com:office:word"
xmlns="http://www.w3.org/TR/REC-html40">
Lokal tarmoqlarni loyihalash va tashkil etish. Tarmoq uzellarini adreslash
Lokal tarmoqlarni loyihalash va tashkil etish.
Tarmoq uzellarini adreslash.
Kompyuterlarda lokal tarmoq orqali maonalari: fizik; kanal; tarmoq; transport; taqdim etish; amaliy.
Uzatuvchi muhitlar. Kanalning oi.
Berilganlarni kommutatsiyalash texnologiyalari.
Ethernet, Fast Ethernet, Token Ring texnologiyalari.
Lokal va global tarmoq protokollari va xususiyatlari.
OSI/ISO standartlari, TCP/IP protokollari.
Internetning ayrim ommaviy xizmatlari.
Mobil aloqa standartlari.
Lokal kompyuter tarmoqlarida axborotni uzatish.
Wi-Fi va Bluetooth standartlari.
Lokal tarmoq texnologiyalari: Ethernet, Fast Ethernet. Tarmoq snifferlari yordamida paketlarni tahlil qilish.
IP adreslar. Sinfli adreslar. Maskalar yordamida adreslash. IP adreslardan tejamkor foydalanish.
http://fayllar.org
| |
Bluetooth Testing | 233 - Learning Kali Linux

with range, we use
hciutil
to scan. You can see an example
of running this scan in
Example 7-16
.
Example 7-16. Using hciutil to identify Bluetooth devices
root@savagewood:/# hcitool scan
Scanning ...
00:9E:C8:93:48:C9 MIBOX3
In spite of the many Bluetooth devices in my house and the reasonably close proxim‐
ity of neighbors, all that was found was a single device. This is because all the other
devices are previously paired or not in pairing mode to be discovered. We can use
hciutil
to
query Bluetooth devices, and we’ll use it for that later. As we are still scan‐
ning for Bluetooth devices, we’re going to move onto another program:
btscanner
.
This has an ncurses-based interface, which is a very rudimentary GUI. It provides the
program more than a line-by-line interface. You can see an example of using it in
Figure 7-11
.
Figure 7-11. btscanner showing Bluetooth devices
You’ll note that we get the same results from
btscanner
as we did from using
hcitool
,
which you’d expect since they are both using the same Bluetooth device and sending
out the standard Bluetooth protocol commands. We get two ways of performing the
scan using
btscanner
. The
first is the inquiry scanner, which sends out probes looking
for devices. The second is a brute-force scan, which sends out specific requests to
addresses. In other words, you provide
a range of addresses for
btscanner
to probe. It
will then send out requests to those
addresses, which are MAC addresses, so they
should look familiar. Communicating with a Bluetooth device is done over layer 2,
234 | Chapter 7: Wireless Security Testing
and as such, we use layer 2 addresses, MAC addresses, to communicate with the devi‐
ces.
If we want to go about brute-forcing Bluetooth devices, there is one last tool that we
are going to take a look at. This is a program called
RedFang
,
which was developed as
a proof of concept to identify nondiscoverable Bluetooth devices. Just because an
inquiry scan doesn’t return much of anything doesn’t mean that there aren’t Bluetooth
devices around. RedFang helps us to identify all of those devices. Once we’ve identi‐
fied them, we may be able to use them down the road a little. Using RedFang, we can
let it scan all possible addresses or we can specify a range. In
Example 7-17
, we’ve
selected a range of addresses to look for devices in.
Example 7-17. Brute-force Bluetooth scanning with RedFang
root@savagewood:/# fang -r 007500000000-0075ffffffff -s
redfang - the bluetooth hunter ver 2.5
(
c
)
2003
@stake Inc
author: Ollie Whitehouse
enhanced: threads by Simon Halsall
enhanced: device info discovery by Stephen Kapp
Scanning
4294967296
address
(
es
)
Address range 00:75:00:00:00:00 -> 00:75:ff:ff:ff:ff
Performing Bluetooth Discovery...
Even just scanning the range 00:75:00:00:00:00 through 00:75:ff:ff:ff:ff, selecting a
range entirely at random, gives us 4,294,967,296 addresses to scan. I’ll save you from
counting the positions. That’s more than 4 billion potential devices. And we’re just
scanning a small slice of the possible number of devices. Scanning the entire range
would be looking through 281,474,976,710,656 device addresses.
Using the Command Line | 23

root@rosebud:~# kill -l
1) SIGHUP 2) SIGINT 3) SIGQUIT 4) SIGILL
5) SIGTRAP 6) SIGABRT 7) SIGBUS 8) SIGFPE
9) SIGKILL 10) SIGUSR1 11) SIGSEGV 12) SIGUSR2
13) SIGPIPE 14) SIGALRM 15) SIGTERM 16) SIGSTKFLT
17) SIGCHLD 18) SIGCONT 19) SIGSTOP 20) SIGTSTP
21) SIGTTIN 22) SIGTTOU 23) SIGURG 24) SIGXCPU
25) SIGXFSZ 26) SIGVTALRM 27) SIGPROF 28) SIGWINCH
29) SIGIO 30) SIGPWR 31) SIGSYS 34) SIGRTMIN
35) SIGRTMIN+1 36) SIGRTMIN+2 37) SIGRTMIN+3 38) SIGRTMIN+4
39) SIGRTMIN+5 40) SIGRTMIN+6 41) SIGRTMIN+7 42) SIGRTMIN+8
43) SIGRTMIN+9 44) SIGRTMIN+10 45) SIGRTMIN+11 46) SIGRTMIN+12
47) SIGRTMIN+13 48) SIGRTMIN+14 49) SIGRTMIN+15 50) SIGRTMAX-14
51) SIGRTMAX-13 52) SIGRTMAX-12 53) SIGRTMAX-11 54) SIGRTMAX-10
55) SIGRTMAX-9 56) SIGRTMAX-8 57) SIGRTMAX-7 58) SIGRTMAX-6
59) SIGRTMAX-5 60) SIGRTMAX-4 61) SIGRTMAX-3 62) SIGRTMAX-2
63) SIGRTMAX-1 64) SIGRTMAX
While a good number of signals are defined, you won’t be using more than a handful.
Commonly, when it comes to managing processes, the SIGTERM signal is most use‐
ful. That’s the signal that
kill
and
killall
issue by default. When SIGTERM isn’t ade‐
quate to get the process to stop, you might need to issue a stronger signal. When
SIGTERM is sent, it’s up to the process to handle the signal and exit. If the process is
hung up, it may need additional help. SIGKILL (signal number 9) will forcefully ter‐
minate the process without relying on the process itself to deal with it.
The second program that you should become acquainted with is
killall
. The differ‐
ence between
kill
and
killall
is that with
killall
you don’t necessarily need the PID.
Instead, you use the name of the process. This can be useful, especially when a parent
may have spawned several child processes. If you want to kill all of them at the same
time, you can use
killall
, and it will do the work of looking up the PIDs from the pro‐
cess table and issuing the appropriate signal to the process. Just as in the case of
kill
,
killall
will take a signal number to send to the process. If you need to forcefully kill all
instances of the process named
firefox
, for instance, you would use
killall -9 firefox
.
Other Utilities
Obviously, we aren’t going to go over the entire list of commands available on the
Linux command line. However, some additional ones are useful to get your head
around. Keep in mind that Unix was designed to have simple utilities that could be
chained together. It does this by having three standard input/output streams: STDIN,
STDOUT, and STDERR. Each process inherits these three streams when it starts.
Input comes in using STDIN, output goes to STDOUT, and errors are sent to
STDERR, though perhaps that all goes without saying. The advantage to this is if you
don’t want to see errors, for example, you can send the STDERR stream somewhere
so you don’t have your normal output cluttered.
User Management | 25 - Learning Kali Linux

The
-m
specified indicates that
useradd
should create the home directory. This will
also populate the home directory with the skeleton files needed for interactive logins.
In the case of the group ID specified,
useradd
requires that the group exist. If you
want your user to have its own group, you can use
groupadd
to create a new group
and then use
useradd
to create the user that belongs to the new group. If you want to
add your user to multiple groups, you can edit the
/etc/group
file and add your user to
the end of each group line you want your user to be a member of. To pick up any
permissions associated with those groups’ access to files, for example, you need to log
out and log back in again. That will pick up the changes to your user, including the
new groups.
Once you have created the user, you should set a password. That’s done using the
passwd
command. If you are root and want to change another user’s password, you
use
passwd kilroy
in the case of the user created in the preceding example. If you just
use
passwd
without a username, you are going to change your own password.
Shells
The common default shell used is the Bourne Again Shell (bash).
However, other shells can be used. If you are feeling adventurous,
you could look at other shells like zsh, fish, csh, or ksh. A shell like
zsh offers the possibility of a lot of customization using features
including plug-ins. If you want to permanently change your shell,
you can either edit
/etc/passwd
or just use
chsh
and have your shell
changed for you.
Service Management
For a long time, there were two styles of service management: the BSD way and the
AT&T way. This is no longer true. There are now three ways of managing services.
Before we get into service management, we should first define a service. A
service
in
this context is a program that runs without any user intervention. The operating envi‐
ronment starts it up automatically and it runs in the background. Unless you got a list
of processes, you may never know it was running. Most systems have a decent num‐
ber of these services running at any point. They are called
services
because they pro‐
vide a service either to the system, to the users, or sometimes to remote users.
Since there is no direct user interaction, generally, in terms of the startup and termi‐
nation of these services, there needs to be another way to start and stop the services
that can be called automatically during startup and shutdown of the system. With the
facility to manage the services in place, users can also use the same facility to start,
stop, restart, and get the status of these services.
| Chapter 1: Foundations of Kali Linux

Administrative Privileges for Services
Services are system-level. Managing them requires administrative
privileges. Either you need to be root or you need to use
sudo
to
gain temporary root privileges in order to perform the service
management functions.
For a
long time, many Linux distributions used the AT&T
init
startup process. This
meant that services were run with a set of scripts that took standard parameters. The
init
startup system used runlevels to determine which services started. Single-user
mode would start up a different set of services than multiuser mode. Even more serv‐
ices would be started up when a display manager is being used, to provide GUIs to
users. The scripts were stored in
/etc/init.d/
and could
be managed by providing
parameters such as
start
,
stop
,
restart
, and
status
. As an example, if you wanted to
start the SSH service,
you might use the command
/etc/init.d/ssh start
. The problem
with the
init
system, though, was that it was generally serial in nature. This caused
performance issues on system startup because every service would be started in
sequence rather than multiple services starting at the same time. The other problem
with the
init
system was that it didn’t support dependencies well. Often,
one service
may rely on other services that had to be started first.
Along comes
systemd
, which was developed by software developers at RedHat. The
goal of
systemd
was to improve the efficiency of the
init
system and overcome some of
its shortcomings. Services can declare dependencies, and services can start in parallel.
There is no longer a need to write bash scripts to start up the services. Instead, there
are configuration files, and all service management
is handled with the program
sys‐
temctl
. To manage a service using
systemctl
, you would use
systemctl verb service
,
where
verb
is the command you are passing and
service
is the name of the service. As
an example, if you wanted to enable the
SSH service and then start it, you would issue
the commands in
Example 1-5
.
Example 1-5. Enabling and starting SSH service
root@rosebud:~# systemctl
enable
ssh
Synchronizing state of ssh.service with
SysV service script with
/lib/systemd/systemd-sysv-install.
Executing: /lib/systemd/systemd-sysv-install
enable
ssh
root@rosebud:~# systemctl start ssh
The first thing we do is enable the service: you are telling your system that when you
boot, you want this service to start. The different system startup modes that the ser‐
vice will start in are configured in the configuration file associated with the service.
Every service has a configuration file. Instead of runlevels, as the old
init
system used,
systemd
uses targets. A
target
is essentially the same as a runlevel, in that it indicates a
| Chapter 1: Foundations of Kali Linux

directory specified and searches all directories under the specified directory. In the
preceding example, we are looking for the file named
foo
. You can use regular expres‐
sions, including wildcards, in your search. If you want to find a file that begins with
the
letters
foo
, you use
find / -name “foo*” -print
. If you are using search patterns, you
need to put the string and pattern inside double quotes. While
find
has a lot of capa‐
bilities, this will get you started.
Process Management
When you
run a program, you initiate a process. You can think of a
process
as a
dynamic, running instance of a program, which is static as it sits on a storage
medium. Every running Linux system has dozens or hundreds of processes running
at any given time.
In most cases, you can expect the operating system to manage the
processes in the best way. However, at times you may want to get yourself involved.
As an example, you may want to check whether a process is running, since not all
processes are running in the foreground. A
foreground process
is one that currently
has the potential for the
user to see and interact with, as compared with a
background
process
, which a user wouldn’t be able to interact with unless it was brought to the
foreground and designed for user interaction. For example, just checking the number
of processes running on an otherwise
idle Kali Linux system, I discovered 141 pro‐
cesses. Out of that 141, only one was in the foreground. All others were services of
some sort.
To get a list of processes, you can use the
ps
command. The command all by itself
doesn’t get you much more than the list of processes that
belong to the user running
the program. Every process, just like files, has an owner and a group. The reason is
that processes need to interact with the filesystem and other objects, and having an
owner and a group is the way the operating system determines
whether the process
should be allowed access. In
Example 1-3
, you can see what just running
ps
looks like.
Example 1-3. Getting a process list
root@rosebud:~# ps
PID TTY TIME CMD
4068 pts/1 00:00:00 bash
4091 pts/1 00:00:00 ps
What you see in
Example 1-3
is the identification
number of the process, commonly
known as the
process ID
, or
PID
, followed by the teletypewriter port the command
was issued on, the amount
of time spent in the processor, and finally the command.
Most of the commands you will see have parameters you can append to the com‐
mand line, and these will change the behavior of the program.
| Chapter 1: Foundations of Kali Linux

Table 1-1. Syslog facilities
Facility number Facility Description
0
kern
Kernel messages
1
user
User-level messages
2
mail
Mail system
3
daemon System daemons
4
auth
Security/authorization messages
5
syslog
Messages generated internally by syslogd
6
lpr
Line printer subsystem
7
news
Network news subsystem
8
uucp
UUCP subsystem
9
Clock daemon
10
authpriv Security/authorization messages
11
ftp
FTP daemon
12
-
NTP subsystem
13
-
Log audit
14
-
Log alert
15
cron
Scheduling daemon
16
local0
Local use 0 (local0)
17
local1
Local use 1 (local1)
18
local2
Local use 2 (local2)
19
local3
Local use 3 (local3)
20
local4
Local use 4 (local4)
21
local5
Local use 5 (local5)
22
local6
Local use 6 (local6)
23
local7
Local use 7 (local7)
Along with the facility is the severity. The severity has
potential values of Emergency,
Alert, Critical, Error, Warning, Notice,
Informational, and Debug. These severities
are
listed in descending order, with the most severe listed first. You may determine
that Emergency logs should be sent somewhere different from other severity levels. In
Example 1-8
, all of the severities are being sent to the log associated with each facility.
The “*” after the facility name indicates all facilities.
If you wanted to, for instance,
send errors from the auth facility
to a specific log file, you would use
auth.error
and
indicate the file you want to use.
Once you
know where the logs are kept, you need to be able to read them. Fortu‐
nately, syslog log entries are easy enough to parse. If you look at
Example 1-11
, you
will see a collection
of log entries from the
auth.log
on a Kali system. Starting on the
«Pоvоrоt» - Burilish - Pedagogika fakulteti

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Pedagogika fakulteti
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bet | 29/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
«Pоvоrоt» - Burilish bandi tanlanganda to’g’ri to’rtburchakni gradus burchak asosiba bajarish nazarda tutiladi. Kerakli qiymat klaviaturadan kiritilib “Enter” tugmasi bosiladi. Yana klaviaturadagi ↓ - ko’rsatkichi bosilib yordamchi menu oyna chaqiriladi. Undagi «Razmеri» - O’lchamlar bandi tanlanib yuqorida aytib o’tilgan tartibda to’g’ri to’rtburchak bajariladi. Shuni aytib o’tish joizki, burchak gradusini kiritayotganda soat strelkasiga teskari yo’nalishda va soatning 3 raqami ko’rsatkichini 0o ekanligini yodda tutish lozim.
2.4. «Rеdaktirоvaniе» - Taxrirlash asboblar paneli
Taxrirlash – bu o’zgartirish demakdir. Taxrirlash asboblar paneli asosan yaratilgan ob’ektlar ustida ishlaydi. Taxrirlash asboblar paneli piktogrammalari bilan tanishib chiqsak:
__ Stеrеt – O’chirish buyrug’i
__ Kоpirоvat – Nusxa olish buyrug’i
__ Zеrkalо – Oyna buyrug’i
__ Pоdоbiе – O’xshatish buyrug’i
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Stеrеt – O’chirish - Pedagogika fakulteti

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Pedagogika fakulteti
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bet | 31/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
Stеrеt – O’chirish buyruq piktogrammasi bosiladi.
Sichqoncha ko’rsatkichi ob’yekt tanlash rejimiga o’tadi va «Vibеritе оb’еkti:» - Ob’ektlarni tanlang: axborotini beradi.
Ob’yekt sichqoncha yordamida tanlanadi.
Sichqoncha o’ng tugmasi bosiladi yoki klaviaturadan “Enter” tugmasi bosiladi.
III usul:
Ob’yekt sichqoncha yordamida tanlanadi.
Klaviaturadan “Delete” tugmasi bosiladi.
Kоpirоvat – Nusxa olish buyrug’i
Ushbu buyruq tugmasi ob’ektlardan nusxa ko’chirish va ularni ko’paytirishni nazarda tutadi.
Taxrirlash ketma-ketligi:
I usul:
Ob’ekt sichqoncha yordamida tanlanadi.
Kоpirоvat – Nusxa olish buyrug’i piktogrammasi tanlanadi.
Ekranga «Bazоvaya tоchka ili ↓» - Bazaviy nuqta yoki ↓ degan axborot chiqadi. Ob’yektning biror nuqtasi sichqoncha yordamida tanlansa, shu nuqta nusxa olingan ob’yektni ko’chirish uchun asos qilib olinadi. Bu usul nusxa olingan ob’yektni aniq bir nuqtasi asosida ko’p nusxada ko’chirishni nazarda tutadi.
Agarda «Bazоvaya tоchka ili ↓» - Bazaviy nuqta yoki ↓ axboroti chiqganda klaviaturadagi ↓ ko’rsatkich bosilib qo’shimcha axborot menusi chaqirilsa unda bitta band – «Pеrеmещеniе» - Ko’chirish mavjud. Bu band ob’yekt (ob’yektlarni) ma’lum bir yo’nalishda, ba’lum bir masofada nusxa olib ko’chirishni nazarda tutadi. Ushbu band “Enter” tugmasi yoki sichqoncha ko’rsatkichi yordamida tanlanadi. Yonalish burchak asosida sichqoncha ko’rsatkichini surish bilan, masofa esa klaviaturadan qiymat asosida kiritiladi va “Enter” tugmasi bilan tasdiqlanadi.
II usul:
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Pedagogika fakulteti - bet 33

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Pedagogika fakulteti
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bet | 33/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
Zеrkalо – Oyna buyrug’i
Ushbu tahrirlash buyrug’i ob’ektni teskari aks tasvirlashni nazarda tutadi.
Shuni aytib o’tish joizki teskari aks tasvirlashda ma’lum bir o’qni ko’rsatish talab etiladi va ob’yekt (ob’yektlar) shu o’qga nisbatan aks tasvirlanadi. Aks tasvirlovchi o’qning ikkita nuqtasi ko’rsatilib, ob’yekt (ob’yektlar)ning barcha nuqtalari shu o’qga nisbatan qancha masofada joylashgan bo’lsa, teskari tomonga ham shuncha masofada joylashadi.
Taxrirlash ketma-ketligi:
I usul:
Ob’ekt sichqoncha yordamida tanlanadi.
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«Visоta» - Balandlik - Pedagogika fakulteti

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Pedagogika fakulteti
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bet | 27/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
«Visоta» - Balandlik bandi tanlansa to’g’ri to’rtburchakka hajm berish maqsadida uning eni va bo’yidan tashqari balandligini berish nazarda tutiladi va ushbu parametrning faoliyati ham uch o’lchamli chizma yaratishda, izometriada yaqqol ko’rinadi, aks holda ikki o’lchamli plan holidagi chizmalarda ushbu parametr ko’rinmaydi. Kerakli qiymat klaviaturadan kiritilib “Enter” tugmasi orqali tasdiqlanadi.
«Shirina» - Kenglik bandi tanlanganda to’g’ri to’rtburchakning chiziqlari kengligi yoki qalinligi tushuniladi. Bunda kerakli qiymat klaviaturadan kiritilib “Enter” tugmasi orqali tasdiqlanadi.
To’gri to’rtburchakning aniq o’lchamlarini, ya’ni eni va bo’yi yoki yuza kattaligida berish uchun, «Pryamоugоlnik» - To’g’ri to’rtburchak chizish tugmasi bosilib dastlabki bosh nuqtasi tanlangandan so’ng, ekranga «Vtоrоy ugоl ili ↓» - Ikkinchi burchak yoki ↓ degan axborot chiqadi. Klaviaturadagi ↓ - ko’rsatkichi bosiladi va yordamchi menu oyna chaqiriladi.
Unda «Plощad» - Yuza, «Razmеri» - O’lchamlar, «Pоvоrоt» - Burilish buyruq bandlari mavjud.
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Moy qovushoqligining haroratga bog‘liqligi

112
yuqori bo‘ladi, bunday moylar yuqori haroratlarda ishqalanayotgan
detallarni ishonchli holda moylaydi, past haroratlarda esa dvigatelni
yurgazib yuborishni qiyinlashtiradigan darajada quyuqlashmaydi.
Ko‘pchilik hollarda moylarning standart haroratlardan bosh-
qa haroratlardagi qovushoqligini aniqlash zarurati paydo bo‘ladi.
Moyning belgilangan qovushoqlikka еgа bo‘lish haroratini (dvi-
gatellar uchun moyning ishga tushirish xususiyatini baholash bilan
bog‘liq bo‘lgan) aniqlash yana-da muhim. Qator tekshirishlar nati-
jasida dvigatelning oson ishga tushirilishini ta’minlaydigan va bun-
da detallarning kuyish va jadal yeyilishining oldini olishni ta’min-
laydigan qovushoqlik chegarasi motor moylari uchun 1 · 10
4
mm
2
/s
deb belgilangan. Moyning ishga tushirish xususiyati deganda, moy
qovushoqligi 1–104 mm
2
/s bo‘ladigan haroratni hisoblash yo‘li bi-
lan aniqlash tushuniladi. Moy qovushoqligi 2–104 mm
2
/s gа yetsa,
moyni moylash tizimida aylanishi to‘xtaydi.
Moy qovushoqligining haroratga bog‘liqlik xususiyatini yax-
shilashning eng samarali usullaridan biri moyga qovushoqligi
yuqori bo‘lgan qo‘shilmalar qo‘shishdir. Bunday qo‘shilmalardan
nisbatan keng tarqalgani molekular massasi 10000–20000 gacha
bo‘lgan poliizobutilendir. Poliizobutilen va boshqa qo‘shilmalarni
moyga 2–5 foiz miqdorida aralashtirish moyning qovushoqligini
bir necha marta (har qanday haroratlarda deyarli bir xil) oshiradi.
Moylarga qo‘shilmalar qo‘shib quyultirish yo‘li bilan bir qa-
tor moylar olinadi, jumladan, keng qo‘llaniladigan moylardan biri
– M–4
3
/6B1 moyi. Vazifasi va 100°C dagi qovushoqligi bir xil
bo‘lgan M–6A va M–4
3
/6B
1
moylarini o‘zaro taqqoslash ularning
harorat ta’sirida o‘z xususiyatlarini turlicha o‘zgartirishini ko‘rsa-
tadi. M–6A moyidan foydalanilganida dvigatelni ishga tushirish
mumkin bo‘lgan eng past harorat (qizdirmasdan) minus 25°C
bo‘lsa, M–4
3
/6B
1
moyidan (quyultirilgan moy) foydalanilganida
esa minus 40°C.
113
5. 1. 5. Moyning turg‘unligi, korroziyaga qarshi
Og‘ir gaz kondensatlarining xossalari

100
Vodorodning diffuziyalanish koeffitsiyenti yuqoriligi yonilg‘i
silindrga har qanday usulda uzatilganida ham bir jinsli aralashma
hosil qilish, dvigatelning barcha ish rejimlarida uni silindrlarga bir
tekis taqsimlash imkonini beradi. Vodorod yonganida lok, so‘xta
va koks hosil bo‘lmaydi, bu esa dvigatel detallarining yeyilishi
va xizmat muddati nuqtayi nazaridan maqbuldir. Ammo vodorod
zichligining kamligi tufayli uning hajmiy energiya sig‘imi nisbatan
pastdir. Vodorodli yonuvchi aralashmaning yonishi benzin-havo
aralashmasining yonish tezligidan 6 barobar tez amalga oshadi.
Vodorodning havo bilan 1 : 10 nisbatdagi ishchi aralashmasi nis-
batan samarali hisoblanadi. Vodorod vodorodli aralashmaning quyi
alangalanish chegarasining kichikligi (vodorod va havo nisbati
1 : 25) va alangalanish energiyasining juda kamligi (benzinga nis-
batan 12–14 barobar kam) bilan ajralib turadi. Vodorodning bu xu-
susiyatlari ishchi aralashmaning kiritish o‘tkazgichlarida chaqnash
hosil bo‘lishi, silindrlardagi ishchi aralashmaning belgilangan pay-
tdan avval alangalanishi, yonish jarayonining shiddatli bo‘lishi,
detonatsiya kabi holatlarni keltirib chiqaradi. Bu holatlar natijasida
karburatorli dvigateldagi ish jarayoni buziladi. Bundan tashqari,
vodorodni saqlash va avtomobilga joylashtirish masalasi yechilishi
lozim bo‘lgan muammolardandir. Masalan, ma’lum zaxira yo‘lini
bosib o‘tishga yetarli bo‘lgan miqdordagi yonilg‘ini (benzin yoki
dizel yonilg‘isi) saqlash uchun yonilg‘i bakining massasi 13–15 kg
bo‘lsa, shuncha yo‘l yurish uchun mo‘ljallangan siqilgan vodorod-
ni saqlash uchun idish tizimining massasi 1300–1400 kg bo‘lishi
lozim.
Shu sabablar tufayli vodorodga uzoq kelajakda neftdan olingan
suyuq yonilg‘ining o‘rnini bosuvchi material sifatida qaraladi. Ho-
zirgi vaqtda vodoroddan suyuq yonilg‘i sarfini kamaytirish uchun
qo‘shilma sifatida foydalanish ustida ish olib borilmoqda.
Pоdоbiе – O’xshatish - Pedagogika fakulteti

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Pedagogika fakulteti
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bet | 38/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
Pоdоbiе – O’xshatish buyruq piktogrammasi tanlanadi.
Ekranga «Ukajitе rasstоyaniе smещеniya ili↓» - Siljish masofasini ko’rsating yoki ↓ axboroti chiqadi. Klaviaturadagi ↓ ko’rsatkichi yordamida qo’shimcha menu chaqiriladi. Unda uchta band «Chеrеz» - Orqali, «Udalit» - O’chirish, «Slоy» - Qatlam mavjud.
«Chеrеz» - Orqali bandi tanlansa ekrandagi siljish nuqtasi sichqoncha yordamida ko’rsatilishi talab etiladi.
«Udalit» - O’chirish bandi tanlansa o’xshatish ob’yekti saqlanib dastlabki ob’yekt o’chiriladi.
«Slоy» - Qatlam bandi qatlamlar bilan ishlashda o’xshash ob’yektlarning holatini belgilaydi: Joriy / Manba.
Tanlangan band asosida axborot chiqariladi.
Sichqoncha ko’rsatkichi ob’yekt tanlash rejimiga o’tadi.
Ekranga «Vibеritе оb’еkt dlya smещеniya ili ↓» - Siljish ob’yektini tanlang yoki ↓ axboroti chiqadi.
Ob’yekt sichqoncha yordamida tanlanadi.
Ob’yekt tashqi yoki ichki (yuqori yoki quyi, o’ng yoki chap) tominidagi ixtiyoriy nuqta sichqoncha yordamida tanlanadi.
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Kоpirоvat – Nusxa olish - Pedagogika fakulteti

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Pedagogika fakulteti
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bet | 32/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
Kоpirоvat – Nusxa olish buyrug’i piktogrammasi tanlanadi.
Sichqoncha ko’rsatkichi ob’ekt tanlash rejimiga o’tadi va «Vibеritе оb’еkti:» - Ob’ektlarni tanlang: axborotini beradi.
Ob’ekt sichqoncha yordamida tanlanadi.
Sichqoncha o’ng tugmasi bosiladi yoki klaviaturadan “Enter” tugmasi bosiladi.
Ekranga «Bazоvaya tоchka ili ↓» - Bazaviy nuqta yoki ↓ degan axborot chiqadi. I usuldagi kabi amallar ketma-ketligi bajariladi.
III usul:
Ob’ekt sichqoncha yordamida tanlanadi.
Sichqoncha o’ng tugmasi yordamida kontekst menu chaqiriladi.
Kontekst menudan kerakli band «Kоpirоvat» yoki «Kоpirоvat s bazоvоy tоchkоy» tanlanadi. «Kоpirоvat s bazоvоy tоchkоy» bandi tanlansa bazaviy nuqta ko’rsatilishi shart.
Sichqoncha o’ng tugmasi yordamida yana kontekst menu chaqiriladi.
Undagi «Vstavit» yoki «Vstavit kak blоk» bandlaridagi shartlardan biri tanlanadi va ob’yekt sichqoncha chap tugmasi yordamida o’rnatiladi.
Izoh: Takroran shu ob’yekt yana o’rnatilishi kerak bolsa, kontekst menu chaqirilib «Vstavit» yoki «Vstavit kak blоk» bandi tanlanadi.
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Polimer qo‘shilmalar - K. J. Matkarimov b. J. Mahmudov a. A. Norqulov avtomobillarda ishlatiladigan ashyolar

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K. J. Matkarimov b. J. Mahmudov a. A. Norqulov avtomobillarda ishlatiladigan ashyolarBog'liq K. J. Matkarimov b. J. Mahmudov a. A. Norqulov avtomobillarda isPolimer qo‘shilmalar. Tarkibida fosfor va oltingugurt bo‘lgan
polimer qo‘shilmalar yuqori yuvish va dispergiyalash xususiyatiga
ega, shuningdek, ko‘pchilik hollarda moyning qovushoqlik-harorat
tavsifini yaxshilaydi, qotish haroratini pasaytiradi, oksidlanishga
qarshi sifatini yaxshilaydi, korrozion aktivligini pasaytiradi. Poli-
mer qo‘shilmalarga tarkibida fosfor, oltingugurt, azot va boshqa
har xil funksional guruhlar makromolekulalarini qo‘shish natijasi-
da ko‘p funksiyali qo‘shilmalar olinadi.
5. 1. 7. Dvigatellarda ishlatiladigan moylar,
ularning ishlash sharoitlari va xossalari
Ichki yonuv dvigatellarining moylash tizimlarida ishlatiladigan
moylar motor moylari deb ataladi. Ularning asosiy vazifasi ishqa-
lanuvchi detallar sirtida mustahkam moy pardasi hosil qilish hisobi-
ga dvigatel detallarining yeyilishini kamaytirishdir. Bunday moylar
juda og‘ir ish sharoitida ishlaydi. Benzinli dvigatelda silindr gil-
zalari 180–200°C, cho‘yan porshenlar yuqori zonada 400–430°C,
aluminiy porshenlar 260–280°C haroratgacha qiziydi. Dizel dvi-
gatellarida esa harorat bundan 50–100°C yuqori bo‘ladi.
Moyning ish sharoitiga ko‘ra dvigatelda uchta zonani ajratish
mumkin:
– yuqori haroratli zona – yonish kamerasi, porshenning yuqori
kallagi va silindrning yuqori qismi. Bu zonadagi ba’zi detallar
400°C gacha (porshen kallagi) va hatto 800°C gacha (chiqarish
klapani) qizishi mumkin, yonuvchi gaz harorati esa 2500°C gacha
yetishi mumkin;
– o‘rtacha haroratli zona – porshen halqalari bilan birgalikda,
porshen barmog‘i, shatunning yuqori qismi va silindr devorlari. Bu
121
zonadagi maksimal harorat (porshen halqalari atrofida) 300–350°C
ga yetadi;
– past haroratli zona – tirsakli val, karter joylashgan uchastkalar.
Bu zonadagi eng yuqori harorat (tayanch va shatun podshipniklari
atrofida) 180°C ga yetadi.
Qizdirilgan dvigatelning o‘rtacha va past haroratli zonalarida
moy jadal bug‘lanishi mumkin. Buning natijasida tizimdagi moy
miqdori kamayadi, sifati esa yomonlashadi. Moy sarfini kamayti-
rish va uning xususiyatlari o‘zgarishiga barham berish uchun aniq
ekspluatatsiya sharoitiga mos keladigan moyni tanlashda moyning
bug‘lanuvchanligiga asoslanish lozim. Ammo moyning fraksion
tarkibini aniqlash murakkab tahlillarni talab etganligi tufayli nis-
batan oddiy tahlil qilish, ya’ni o‘t oldirish haroratini aniqlash usu-
lidan foydalaniladi.
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Yengil gaz kondensatlarining xossalari

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Yengil gaz kondensatlarining xossalariBog'liq K. J. Matkarimov b. J. Mahmudov a. A. Norqulov avtomobillarda isYengil gaz kondensatlarining xossalari
Topilgan
joyi
Oktan
soni
(M. Y.)
Friksion tarkib uchun haydash
harorati, °C
Qovu-
shoqligi,
10° m
3
/s
Zich-
ligi,
kg/dm
3
qaynash
boshlan. 10% 50% 90%
qaynash
oxiri
Janubiy
Muborak
64,2
40
74
109 163
206
0,76
0,72
Shimoliy
Muborak
65,1
36
75
118 196
230
0,765
0,731
Garli
66,5
56
101 128 175
232
0,889
0,757
Og ir gaz kondensatlari Shoxpaxti, Achak, Shatlik, Karim, Is-
lim, Qora-Chop, Ravot, Gugurtli va boshqa gaz konlaridan olinadi.
Ularda dizel yonilg‘isinikiga qaraganda yengil fraksiyalar ko‘proq
bo‘ladi. Bu jihat dizelning ishga tushish xususiyatlarini yaxshilash
va o‘z-o‘zidan alangalanishgacha bo‘lgan davrda yonish kame-
rasida bug‘lanishni jadallashtirishga olib kelishi kerak. Shu bilan
birga, smolali qoldiqlar, so‘xta va ishlatilgan gazlarda tutun hosil
qiladigan og‘ir fraksiyalar miqdori mazkur kondensatlarda standart
yonilg‘iga qaraganda sezilarli darajada kam bo‘ladi va u dizel xusu-
siyatlariga ijobiy ta’sir ko‘rsatadi. Ko‘pgina gaz kondensatlarining
setan soni 40–65 oralig‘ida, ya’ni dizel yonilg‘isining setan soniga
teng yoki biroz yuqori bo‘ladi. Bu jihat odatdagidek rostlashlarda
dvigatelning ancha ravon ishlashini ta’minlaydi. Gaz kondensat-
larining zichligi va qovushoqligi, odatda, dizel yonilg‘isining qo-
vushoqligidan kam bo‘ladi, bu esa dizel yonilg‘isiga mo‘ljallangan
yonilg‘i tizimidagi sikl davomida beriladigan yonilg‘i miqdorining
biroz kamayishiga va purkash bosimining pasayishiga olib kelishi
mumkin. Agar dizel ko‘rsatkichlari standart yonilg‘ilarda ishlagani-
99
dagi ko‘rsatkichlardan sezilarli darajada yomonlashadigan bo‘lsa,
gaz kondensatlarining qovushoqligini maxsus quyuqlashtirgichlar,
masalan, poliizobutilen yoki dizel yonilg‘isi qo‘shib oshirish mum-
kin. Natijada standart yonilg‘iga bo‘lgan talab 40–50 foiz kamaya-
di. Og‘ir gaz kondensatlarining ba’zi bir xossalari 4. 4- jadvalda
keltirilgan.
4. 4- jadval
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«Оtmеna» - Rad etish - Pedagogika fakulteti

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Pedagogika fakulteti
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bet | 40/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
«Оtmеna» - Rad etish.
«Prоsmоtr» - Namoyish (oldindan ko’rish). Ushbu tugma tanlanganda hosil qilingan massiv namoyish etiladi va «Massiv» - Massiv axborot oynasi ochiladi. Unda «Prinyat» - Qabul qilish, «Izmеnit» - O’zgartirish va «Оtmеna» - Rad etish interfaol tugmalari mavjud. Kerakli buyruq tanlanadi.
II usul: Aylanma massiv yaratish.
Ob’ekt (Ob’yektlar)sichqoncha yordamida tanlanadi.
Massiv... – Massiv… ko’paytirish buyrug’i piktogrammasi bosiladi.
Ekranda «Massiv» - Massiv axborot oynasi ochiladi.
Oynadagi ikkinchi «Krugоvоy massiv» - Aylanma massiv doira bo’lim tugmasi tanlanadi.
Ekrandagi «Massiv» - Massiv axborot oynasi tuzilishi o’zgaradi.
Oyna quyidagi tuzilishga ega:
«Vibоr оb’еktоv» - Ob’yektlar tanlash ko’rsatkichi.
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«Tsеntr» - Markaz - Pedagogika fakulteti

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Pedagogika fakulteti
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bet | 41/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
«Tsеntr» - Markaz bandi va ko’rsatkichi. X va Y o’qlar bo’yicha koordinata qiymatlari kiritilishini nazarda tutadi yoki ko’rsatkich tugmasi tanlansa oyna yopilib, ekranda aylantirish markazi sichqoncha yordamida tanlanadi.
Izoh: Ko’rsatkich yordamida markazni belgilash qulay variant.
«Spоsоb pоstrоеniya:» - Yasash usuli bandining ko’rsatkich oynasida «Chislо pоstrоеniya i Ugоl zapоlnеniya» - Yasashlar soni va to’ldirish burchagi degan yozuv ko’rinib turadi. Ko’rsatkich oynanig o’ng tomonida (v) ko’rsatkichi mavjud bo’lib, u yordamida ini nazarda tutadi yoki ko'boshqa yasash usulini tanlash mumkin.
Ko’rsatkich tanlanganda qo’shimcha ikkita usul borligi ko’rinadi. Bular:
«Chislо elеmеntоv i Ugоl mеjdu elеmеntami» - Elementlar soni va ular orasidagi burchak bandi va «Ugоl zapоlnеniya i Ugоl mеjdu elеmеntami» - To’ldirish burchagi va elementlar orasidagi burchak.
Shu bandlar talablariga mos ravishda quyidagi qiymat kiritish oynachalari faollashadi:
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Massiv... – Massiv… ko’paytirish buyrug’i

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Massiv... – Massiv… ko’paytirish buyrug’i
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bet | 39/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
Massiv... – Massiv… ko’paytirish buyrug’i
Ushbu buyruq tugmasi ob’yekt (ob’yekylar)ni siljitib ko’paytirishni nazarda tutadi. Bunda siljish gorizontal va vertikal yo’nalishda yoki aylanma harakat asosida bo’lishi mumkin. Massiv – ko’paytirish demakdir.
Taxrirlash ketma-ketligi:
I usul: To’rtburchak massiv yaratish.
Ob’ekt (Ob’yektlar)sichqoncha yordamida tanlanadi.
Massiv... – Massiv… ko’paytirish buyrug’i piktogrammasi bosiladi.
Ekranda «Massiv» - Massiv axborot oynasi ochiladi.
Oyna ikkita bo’lim, «Vibоr оb’еktоv» - Ob’yektlar tanlash ko’rsatkichi, namuna oynasi va interfaol tugmalardan iborat.
Birinchi bo’limda massivning asosiy parametrlari «Ryadоv:» - Qatorlari:, «Stоlbtsоv:» - Ustunlari bandlari bo’lib, muloqot oynachalari sichqoncha yordamida tanlanib kerakli qiymat kiritiladi.
Ikkinchi bo’limda esa «Mеjdu ryadami:» - Qatorlar orasi:, Mеjdu stоlbtsami:» - Ustunlar orasi: va «Ugоl pоvоrоta:» - Burilish burchagi bandlari mavjud. Ushbu bandlardagi muloqot oynachalariga ham kerakli qiymat kiritiladi.
Barcha parametrlar o’rnatib bo’lingandan so’ng interfaol tugmalarga o’tiladi.
«ОK» - amallarni tasdiqlaydi va massivni hosil qiladi.
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Moylarning ishchi haroratdagi qovushoqligi

110
Moy ishchi haroratda ma’lum qovushoqlikka еgа bo‘lishi va harorat
ta’sirida moy qovushoqligi imkoniyat qadar kam o‘zgarishi lozim.
Moylarning qovushoqligi mexanizmlar ishiga katta ta’sir ko‘rsa-
tadi. Har bir konkret hol uchun qovushoqlikni to‘g‘ri tanlash lozim.
Qovushoqligi juda ham past bo‘lgan moylar detallar orasidagi tir-
qishdan osongina oqib chiqib ketadi, natijada detallarning yeyilishi
jadallashadi va moylash materialining sarfi ortadi. Aksincha, moy
qovushoqligi juda ham yuqori bo‘lganida, o‘zaro ishqalanuvchi de-
tallar orasidagi tirqishga moy yetkazib berish qiyinlashadi, buning
natijasida ham detallarning yeyilishi jadallashadi. Shu bilan birga,
moylangan yoki moy vannasiga cho‘ktirilgan detallarni harakatlan-
tirish uchun energiya sarfi ortib ketadi (5. 2 rasm).
5. 2- rasm. Moy qovushoqligining harorat t ga bog‘liqligi:
1 – М–10Г
2
;
2 – М –6А;
3 – M–4
3
F
6
B
1
.
Turli maqsadlarda ishlatiladigan mexanizm va agregatlarni moy-
lashda ishlatiladigan moylarning ishchi harorati bir xil bo‘lmaydi.
Sanoatda ishlatiladigan jihozlarda foydalaniladigan moylarning ish
harorati taxminan 50°C bo‘ladi, shuning uchun standartlarda sa-
111
noat moylari uchun 50°C dagi qovushoqlik beriladi. Motor moyla-
rining ishchi harorati 100°C deb qabul qilingan, ya’ni ichki yonuv
dvigatellarining past haroratli zonasidagi (karter, tirsakli val) moy
haroratining o‘rtacha qiymati. Ko‘pchilik avtomobillarning trans-
missiyasida ishlatiladigan moylarning maksimal harorati 100°C ga
yaqin bo‘lganligi uchun transmission moylarning qovushoqlik xu-
susiyatlari ham 100°C dagi qovushoqlikka nisbatan beriladi.
Barcha turdagi motor moylarini va bir qator transmission moy-
larni markalashda moyning 100°C haroratdagi qovushoqligi o‘z
aksini topadi. Masalan, М8Б
1
markali moyda 8 raqami moyning
100°C dagi qovushoqligini bildiradi.