yz2022/T2P-DownstreamNLP huggingface dataset:
Antenna_(radio)

For horizontal propagation between transmitting and receiving antennas situated near the ground reasonably far from each other, the distances traveled by tne direct and reflected rays are nearly the same. There is almost no relative phase shift. If the emission is polarized vertically, the two fields (direct and reflected) add and there is maximum of received signal. If the signal is polarized horizontally, the two signals subtract and the received signal is largely cancelled. The vertical plane radiation patterns are shown in the image at right. With vertical polarization there is always a maximum for θ=0, horizontal propagation (left pattern). For horizontal polarization, there is cancellation at that angle. Note that the above formulae and these plots assume the ground as a perfect conductor. These plots of the radiation pattern correspond to a distance between the antenna and its image of 2.5λ. As the antenna height is increased, the number of lobes increases as well.

Question: What is also increased along with the antenna's height?
Answer: lobes

Question: What is between recieving and transmitting antenna's?
Answer: horizontal propagation

Question: Where is the radiation patterns in the vertical plane shown?
Answer: image at right
51st_state

The Party of Reconstruction in Sicily, which claimed 40,000 members in 1944, campaigned for Sicily to be admitted as a U.S. state. This party was one of several Sicilian separatist movements active after the downfall of Italian Fascism. Sicilians felt neglected or underrepresented by the Italian government after the annexation of 1861 that ended the rule of the Kingdom of the Two Sicilies based in Naples. The large population of Sicilians in America and the American-led Allied invasion of Sicily in July–August 1943 may have contributed to the sentiment.

Question: How many members did the Party of Reconstruction in Sicily have in 1944?
Answer: 40,000 members

Question: When did the annexation of Sicily by Italy happen?
Answer: 1861

Question: When did the Allied invasion of Sicily occur?
Answer: July–August 1943
Antenna_(radio)

According to reciprocity, the efficiency of an antenna used as a receiving antenna is identical to the efficiency as defined above. The power that an antenna will deliver to a receiver (with a proper impedance match) is reduced by the same amount. In some receiving applications, the very inefficient antennas may have little impact on performance. At low frequencies, for example, atmospheric or man-made noise can mask antenna inefficiency. For example, CCIR Rep. 258-3 indicates man-made noise in a residential setting at 40 MHz is about 28 dB above the thermal noise floor. Consequently, an antenna with a 20 dB loss (due to inefficiency) would have little impact on system noise performance. The loss within the antenna will affect the intended signal and the noise/interference identically, leading to no reduction in signal to noise ratio (SNR).

Question: At lesser frequencies what can account for incorrect assumptions about efficiency?
Answer: man-made noise

Question: In what type of programs would low efficiency antennas not make a difference in effectiveness?
Answer: receiving

Question: What is SNR?
Answer: signal to noise ratio
51st_state

The implication has historical basis and dates to the breakup of British America during the American Revolution. The colonies that had confederated to form the United States invaded Canada (at the time a term referring specifically to the modern-day provinces of Quebec and Ontario, which had only been in British hands since 1763) at least twice, neither time succeeding in taking control of the territory. The first invasion was during the Revolution, under the assumption that French-speaking Canadians' presumed hostility towards British colonial rule combined with the Franco-American alliance would make them natural allies to the American cause; the Continental Army successfully recruited two Canadian regiments for the invasion. That invasion's failure forced the members of those regiments into exile, and they settled mostly in upstate New York. The Articles of Confederation, written during the Revolution, included a provision for Canada to join the United States, should they ever decide to do so, without needing to seek U.S. permission as other states would. The United States again invaded Canada during the War of 1812, but this effort was made more difficult due to the large number of Loyalist Americans that had fled to what is now Ontario and still resisted joining the republic. The Hunter Patriots in the 1830s and the Fenian raids after the American Civil War were private attacks on Canada from the U.S. Several U.S. politicians in the 19th century also spoke in favour of annexing Canada.

Question: During which the US invade Canada?
Answer: the War of 1812
Antenna_(radio)

According to reciprocity, the efficiency of an antenna used as a receiving antenna is identical to the efficiency as defined above. The power that an antenna will deliver to a receiver (with a proper impedance match) is reduced by the same amount. In some receiving applications, the very inefficient antennas may have little impact on performance. At low frequencies, for example, atmospheric or man-made noise can mask antenna inefficiency. For example, CCIR Rep. 258-3 indicates man-made noise in a residential setting at 40 MHz is about 28 dB above the thermal noise floor. Consequently, an antenna with a 20 dB loss (due to inefficiency) would have little impact on system noise performance. The loss within the antenna will affect the intended signal and the noise/interference identically, leading to no reduction in signal to noise ratio (SNR).

Question: What is the median level for measuring atmospheric noise?
Answer: thermal noise floor
51st_state

The Party of Reconstruction in Sicily, which claimed 40,000 members in 1944, campaigned for Sicily to be admitted as a U.S. state. This party was one of several Sicilian separatist movements active after the downfall of Italian Fascism. Sicilians felt neglected or underrepresented by the Italian government after the annexation of 1861 that ended the rule of the Kingdom of the Two Sicilies based in Naples. The large population of Sicilians in America and the American-led Allied invasion of Sicily in July–August 1943 may have contributed to the sentiment.

Question: What did the Party of Reconstruction in Sicily campaign for?
Answer: for Sicily to be admitted as a U.S. state
Antenna_(radio)

The phase of reflection of electromagnetic waves depends on the polarization of the incident wave. Given the larger refractive index of the ground (typically n=2) compared to air (n=1), the phase of horizontally polarized radiation is reversed upon reflection (a phase shift of  radians or 180°). On the other hand, the vertical component of the wave's electric field is reflected at grazing angles of incidence approximately in phase. These phase shifts apply as well to a ground modelled as a good electrical conductor.

Question: When is polarized radiation reversed?
Answer: reflection
Antenna_(radio)

The bandwidth characteristics of a resonant antenna element can be characterized according to its Q, just as one uses to characterize the sharpness of an L-C resonant circuit. However it is often assumed that there is an advantage in an antenna having a high Q. After all, Q is short for "quality factor" and a low Q typically signifies excessive loss (due to unwanted resistance) in a resonant L-C circuit. However this understanding does not apply to resonant antennas where the resistance involved is the radiation resistance, a desired quantity which removes energy from the resonant element in order to radiate it (the purpose of an antenna, after all!). The Q is a measure of the ratio of reactance to resistance, so with a fixed radiation resistance (an element's radiation resistance is almost independent of its diameter) a greater reactance off-resonance corresponds to the poorer bandwidth of a very thin conductor. The Q of such a narrowband antenna can be as high as 15. On the other hand, a thick element presents less reactance at an off-resonant frequency, and consequently a Q as low as 5. These two antennas will perform equivalently at the resonant frequency, but the second antenna will perform over a bandwidth 3 times as wide as the "hi-Q" antenna consisting of a thin conductor.

Question: The properties of a usable radio frequency can be called its?
Answer: Q

Question: What is the largest Q that could be achieved with a slimmer band antenna?
Answer: 15

Question: What type of element would be used to encounter less reactance?
Answer: thick

Question: What is a measure of the comparison between reactance and resistance?
Answer: Q
Antenna_(radio)

However loss resistance will generally affect the feedpoint impedance, adding to its resistive (real) component. That resistance will consist of the sum of the radiation resistance Rr and the loss resistance Rloss. If an rms current I is delivered to the terminals of an antenna, then a power of I2Rr will be radiated and a power of I2Rloss will be lost as heat. Therefore, the efficiency of an antenna is equal to Rr / (Rr + Rloss). Of course only the total resistance Rr + Rloss can be directly measured.

Question: What can increase the feedpoint impedance of a component?
Answer: loss resistance

Question: The addition of Rr and Rloss equals what?
Answer: resistance

Question: What equation an determine an antennas effectiveness?
Answer: Rr / (Rr + Rloss)
Antenna_(radio)

Due to reciprocity (discussed above) the gain of an antenna used for transmitting must be proportional to its effective area when used for receiving. Consider an antenna with no loss, that is, one whose electrical efficiency is 100%. It can be shown that its effective area averaged over all directions must be equal to λ2/4π, the wavelength squared divided by 4π. Gain is defined such that the average gain over all directions for an antenna with 100% electrical efficiency is equal to 1. Therefore, the effective area Aeff in terms of the gain G in a given direction is given by:

Question: What must the relationship of an antenna and the receiving area be due to reciprocity?
Answer: proportional

Question: hat could an antenna with complete electrical efficiency be said to have?
Answer: 1

Question: what could an antenna with complete electrical efficiency be said to have?
Answer: no loss

Question: Another term for the effective area is?
Answer: Aeff
Antenna_(radio)

However loss resistance will generally affect the feedpoint impedance, adding to its resistive (real) component. That resistance will consist of the sum of the radiation resistance Rr and the loss resistance Rloss. If an rms current I is delivered to the terminals of an antenna, then a power of I2Rr will be radiated and a power of I2Rloss will be lost as heat. Therefore, the efficiency of an antenna is equal to Rr / (Rr + Rloss). Of course only the total resistance Rr + Rloss can be directly measured.

Question: What is the single factor that can be precisely measured?
Answer: total resistance
Antenna_(radio)

Monopole antennas consist of a single radiating element such as a metal rod, often mounted over a conducting surface, a ground plane. One side of the feedline from the receiver or transmitter is connected to the rod, and the other side to the ground plane, which may be the Earth. The most common form is the quarter-wave monopole which is one-quarter of a wavelength long and has a gain of 5.12 dBi when mounted over a ground plane. Monopoles have an omnidirectional radiation pattern, so they are used for broad coverage of an area, and have vertical polarization. The ground waves used for broadcasting at low frequencies must be vertically polarized, so large vertical monopole antennas are used for broadcasting in the MF, LF, and VLF bands. Small monopoles are used as nondirectional antennas on portable radios in the HF, VHF, and UHF bands.

Question: Monopole antennas consist of what element?
Answer: metal rod

Question: What are small monopoles used as?
Answer: nondirectional antennas

Question: What the most common form? 
Answer: quarter-wave monopole
Antenna_(radio)

For instance, if a transmitter delivers 100 W into an antenna having an efficiency of 80%, then the antenna will radiate 80 W as radio waves and produce 20 W of heat. In order to radiate 100 W of power, one would need to use a transmitter capable of supplying 125 W to the antenna. Note that antenna efficiency is a separate issue from impedance matching, which may also reduce the amount of power radiated using a given transmitter. If an SWR meter reads 150 W of incident power and 50 W of reflected power, that means that 100 W have actually been absorbed by the antenna (ignoring transmission line losses). How much of that power has actually been radiated cannot be directly determined through electrical measurements at (or before) the antenna terminals, but would require (for instance) careful measurement of field strength. Fortunately the loss resistance of antenna conductors such as aluminum rods can be calculated and the efficiency of an antenna using such materials predicted.

Question: What would need to be investigated to determine how much power was radiated?
Answer: electrical measurements
Antenna_(radio)

Monopole antennas consist of a single radiating element such as a metal rod, often mounted over a conducting surface, a ground plane. One side of the feedline from the receiver or transmitter is connected to the rod, and the other side to the ground plane, which may be the Earth. The most common form is the quarter-wave monopole which is one-quarter of a wavelength long and has a gain of 5.12 dBi when mounted over a ground plane. Monopoles have an omnidirectional radiation pattern, so they are used for broad coverage of an area, and have vertical polarization. The ground waves used for broadcasting at low frequencies must be vertically polarized, so large vertical monopole antennas are used for broadcasting in the MF, LF, and VLF bands. Small monopoles are used as nondirectional antennas on portable radios in the HF, VHF, and UHF bands.

Question: What has vertical polarization?
Answer: Monopoles
Flowering_plant

The flowering plants (angiosperms), also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with about 350,000 species. Like gymnosperms, angiosperms are seed-producing plants; they are distinguished from gymnosperms by characteristics including flowers, endosperm within the seeds, and the production of fruits that contain the seeds. Etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant. The term "angiosperm" comes from the Greek composite word (angeion-, "case" or "casing", and sperma, "seed") meaning "enclosed seeds", after the enclosed condition of the seeds.

Question: How many species of flowering plants are there about?
Answer: 350,000

Question: What is the Greek word for "case" or "casing"?
Answer: angeion

Question: What does an angiosperm produce its seeds within?
Answer: an enclosure
Antenna_(radio)

This is a consequence of Lorentz reciprocity. For an antenna element  not connected to anything (open circuited) one can write . But for an element  which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance, with the so-called parasitic elements of a Yagi-Uda antenna where the solid rod can be viewed as a dipole antenna shorted across its feedpoint. Parasitic elements are unpowered elements that absorb and reradiate RF energy according to the induced current calculated using such a system of equations.

Question: a antenna element not connected to anything is circuited how?
Answer: open circuited

Question: What element absorbs and reradiate RF-energy?
Answer: Parasitic

Question: Where can this solid rod be viewed?
Answer: feedpoint

Question: What antenna can the solid rod be viewed as a dipole antenna?
Answer: Yagi-Uda
Flowering_plant

The evolution of seed plants and later angiosperms appears to be the result of two distinct rounds of whole genome duplication events. These occurred at 319 million years ago and 192 million years ago. Another possible whole genome duplication event at 160 million years ago perhaps created the ancestral line that led to all modern flowering plants. That event was studied by sequencing the genome of an ancient flowering plant, Amborella trichopoda, and directly addresses Darwin's "abominable mystery."

Question: When did the first whole genome duplication event occur?
Answer: 319 million years ago

Question: How are duplication events studied?
Answer: by sequencing the genome of an ancient flowering plant

Question: What type of event perhaps created the line which led to modern flowering plants?
Answer: whole genome duplication

Question: How many distinct rounds of genome duplication events are suspected in the evolution of seed plants?
Answer: two

Question: Who coined the term "abominable mystery"?
Answer: Darwin
Antenna_(radio)

This is a consequence of Lorentz reciprocity. For an antenna element  not connected to anything (open circuited) one can write . But for an element  which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance, with the so-called parasitic elements of a Yagi-Uda antenna where the solid rod can be viewed as a dipole antenna shorted across its feedpoint. Parasitic elements are unpowered elements that absorb and reradiate RF energy according to the induced current calculated using such a system of equations.

Question: When is the element not allowed voltage?
Answer: short circuited
Antenna_(radio)

Consider a half-wave dipole designed to work with signals 1 m wavelength, meaning the antenna would be approximately 50 cm across. If the element has a length-to-diameter ratio of 1000, it will have an inherent resistance of about 63 ohms. Using the appropriate transmission wire or balun, we match that resistance to ensure minimum signal loss. Feeding that antenna with a current of 1 ampere will require 63 volts of RF, and the antenna will radiate 63 watts (ignoring losses) of radio frequency power. Now consider the case when the antenna is fed a signal with a wavelength of 1.25 m; in this case the reflected current would arrive at the feed out-of-phase with the signal, causing the net current to drop while the voltage remains the same. Electrically this appears to be a very high impedance. The antenna and transmission line no longer have the same impedance, and the signal will be reflected back into the antenna, reducing output. This could be addressed by changing the matching system between the antenna and transmission line, but that solution only works well at the new design frequency.

Question: How big would an antenna be used to with with one m wavelengths?
Answer: 50 cm

Question:  What unit is used to measure current?
Answer: ampere

Question: How could the rection of output be adressed by?
Answer: changing the matching system

Question: What effect occurs when the signal is reflected back into the antenna?
Answer: reducing output
Flowering_plant

The flowering plants (angiosperms), also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with about 350,000 species. Like gymnosperms, angiosperms are seed-producing plants; they are distinguished from gymnosperms by characteristics including flowers, endosperm within the seeds, and the production of fruits that contain the seeds. Etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant. The term "angiosperm" comes from the Greek composite word (angeion-, "case" or "casing", and sperma, "seed") meaning "enclosed seeds", after the enclosed condition of the seeds.

Question: What do angiosperms have in common with gymnosperms?
Answer: seed-producing plants

Question: What are the most diverse group of land plants?
Answer: angiosperms
Antenna_(radio)

For example, at 30 MHz (10 m wavelength) a true resonant 1⁄4-wavelength monopole would be almost 2.5 meters long, and using an antenna only 1.5 meters tall would require the addition of a loading coil. Then it may be said that the coil has lengthened the antenna to achieve an electrical length of 2.5 meters. However, the resulting resistive impedance achieved will be quite a bit lower than the impedance of a resonant monopole, likely requiring further impedance matching. In addition to a lower radiation resistance, the reactance becomes higher as the antenna size is reduced, and the resonant circuit formed by the antenna and the tuning coil has a Q factor that rises and eventually causes the bandwidth of the antenna to be inadequate for the signal being transmitted. This is the major factor that sets the size of antennas at 1 MHz and lower frequencies.

Question: How would the resistive impedance from this scenario compare to if the antenna was the proper height?
Answer: lower
Flowering_plant

Fossilized spores suggest that higher plants (embryophytes) have lived on land for at least 475 million years. Early land plants reproduced sexually with flagellated, swimming sperm, like the green algae from which they evolved. An adaptation to terrestrialization was the development of upright meiosporangia for dispersal by spores to new habitats. This feature is lacking in the descendants of their nearest algal relatives, the Charophycean green algae. A later terrestrial adaptation took place with retention of the delicate, avascular sexual stage, the gametophyte, within the tissues of the vascular sporophyte. This occurred by spore germination within sporangia rather than spore release, as in non-seed plants. A current example of how this might have happened can be seen in the precocious spore germination in Selaginella, the spike-moss. The result for the ancestors of angiosperms was enclosing them in a case, the seed. The first seed bearing plants, like the ginkgo, and conifers (such as pines and firs), did not produce flowers. The pollen grains (males) of Ginkgo and cycads produce a pair of flagellated, mobile sperm cells that "swim" down the developing pollen tube to the female and her eggs.

Question: How did early plants reproduce sexually?
Answer: with flagellated, swimming sperm

Question: How long have higher plants lived on land?
Answer: at least 475 million years

Question: What are the nearest algal relatives existing today?
Answer: Charophycean green algae

Question: What is the common name for Selaginella?
Answer: the spike-moss
Flowering_plant

The exact relationship between these eight groups is not yet clear, although there is agreement that the first three groups to diverge from the ancestral angiosperm were Amborellales, Nymphaeales, and Austrobaileyales. The term basal angiosperms refers to these three groups. Among the rest, the relationship between the three broadest of these groups (magnoliids, monocots, and eudicots) remains unclear. Some analyses make the magnoliids the first to diverge, others the monocots. Ceratophyllum seems to group with the eudicots rather than with the monocots.

Question: How clear is the relationship between the broadest of the three non-basal angiosperm groups?
Answer: unclear