A precise description of a deliverable is called a ().
A:specification B:baseline C:work package D:work breakdown structure element
Hominids started walking on two legs six million years ago, shortly after diverging from chimpanzees, according to a study of the inner structure of a fossilised thighbone. The finding puts upright posture at the base of the human family tree.
The evolution of upright posture is a key issue in anthropology. Together with large brain size, it marks the dividing line between humans and the great apes.
Researchers know that upright posture evolved first because the skeleton of famed Australopithecine,Lucy, has a small braincase but modem ankles. Yet with few known fossils older than about four million years, the details of how and when upright posture evolved have been hazy. Over the past few years, however, two important new finds have begun to fill in the gaps.
The older animal is Sahelanthropus tchadensis, which lived in Chad six to seven million years ago, but only its hominid cranium was found. More complete is the chimpanzee-sized Orrorin tugenensis, as 20 fossils from at least five individuals have been found in Kenya. These are about six million years old.
A team led by Brigitte Senut of the French Museum of Natural History in Paris initially classed Orrorin as a hominid, on the human side of the split from chimpanzees. This classification was based on skeletal features, but other anthropologists remained sceptical.
To address those doubts, Robert Eckhardt of Pennsylvania State University in the US carried out a CT scan on the most complete of Orrorin’s three thighbones. He hoped that revealing its internal structure would indicate the biomechanical use of the bone.
The critical part of each thighbone—which consists of a strong outer cortex and a spongy core—is the neck shaft that connects the top part of bone with the hip joint. Essentially, the thighbones are supporting a horizontal pelvic beam that takes the weight of the head and body. The precise load this places on the thighbones depends on body posture, and this determines the musculature and structure of the thighbones.
In knuckle-walking chimps, the cortex is the same thickness on the top and bottom of the bone. However, bipedal, upright walking applies different forces, which means the codex in humans is at least four times thicker on the bottom part of the bone.
Fossilisation usually obscures the internal structures of bones, so " there aren’t many hominids in which scanning will work " , Eckhardt told New Scientist.
However, with Orrorin he was lucky. He and a research group including Senut found that the lower part of the thighbone in Orrorin is three times thicker than the upper—making its walking habits much closer to humans than chimps.
In the sentence " this determines the musculature and… " (Para 7), " this " refers to_______.
A:the precise load B:the thighbone C:body posture D:horizontal pelvic beam
Narrative crept back into art through a side door marked fashion photography. In April 1967, French Vogue published a spread by Bob Richardson, the American photographer, that soon became a legend Informally christened " the Greek trip " by Richardson’s admirers, the spread featured Donna Mitchell, a striking brunet model, hanging out on the Aegean island of Rhodes with a male companion.
Of course, narrative never disappeared—it just went to the movies, and stayed, and stayed. But what had caused stories to be exiled from high art The idea of essence, and the equation of essence with goodness. Can you imagine Visual art is essentially composed of form, color, materials. Anything to do with content is extraneous and therefore to be associated with badness; therefore to be eliminated. Moreover, content, says this line of thought, is controlling. This means that a rose is the Virgin Mary (depending on what the meaning of " is " is). And art, like society, must be liberated from such hierarchically imposed values. What this argument overlooked, of course, is that narrative is a form in itself, not just a vehicle for content. Indeed, the ideology of formalism originated, in Soviet Russia, with the analysis of old folk tales. Narrative form, the analysis went, typically proceeds from an initial state of equilibrium through a series of destabilizing episodes, concluding with a heightened state of equilibrium at the end. Think Indiana Jones. You can plug whatever content you want in there as long as it creates the form. Each episode simply has to do with the work of creating disequilibrium.
A narrative does not, in other words, tell a story. A story is told to give listeners the pleasure of the narrative form. If you were to isolate the form of disequilibrium from the specifics of plot, you might arrive at something resembling the collected work of Cindy Sherman. Initially modeled after movie stills, Sherman’s pictures are not, of course, abstract. Over the years, in fact, their content has become increasingly elaborate. I see this as a form of generosity as well as a sign of advanced technical skills. Not since Giuseppe Arcimboldo (1527-1593), perhaps, has an artist contrived to turn the human figure into a more bountiful cornucopia for the eye.
Yet even the most visually splendid of Sherman’s images are minimalist, in that they reduce the narrative down to the precise moment when the center of gravity shifts. Perhaps some unheard word is spoken. A floorboard squeaks. From upstairs comes a thump. And a tentative state of equilibrium gives way to anxiety or dread. That moment, too, represents essence. What more do you need to know
We can learn from the last paragraph that______.
A:a successful film should consist of precise moments B:a tentative state of equilibrium is superior to anxiety or dread C:a reduction is necessary to make the narrative efficient D:a proper moment is enough to achieve narrative purpose
Narrative crept back into art through a side door marked fashion photography. In April 1967, French Vogue published a spread by Bob Richardson, the American photographer, that soon became a legend Informally christened " the Greek trip " by Richardson’s admirers, the spread featured Donna Mitchell, a striking brunet model, hanging out on the Aegean island of Rhodes with a male companion.
Of course, narrative never disappeared—it just went to the movies, and stayed, and stayed. But what had caused stories to be exiled from high art The idea of essence, and the equation of essence with goodness. Can you imagine Visual art is essentially composed of form, color, materials. Anything to do with content is extraneous and therefore to be associated with badness; therefore to be eliminated. Moreover, content, says this line of thought, is controlling. This means that a rose is the Virgin Mary (depending on what the meaning of " is " is). And art, like society, must be liberated from such hierarchically imposed values. What this argument overlooked, of course, is that narrative is a form in itself, not just a vehicle for content. Indeed, the ideology of formalism originated, in Soviet Russia, with the analysis of old folk tales. Narrative form, the analysis went, typically proceeds from an initial state of equilibrium through a series of destabilizing episodes, concluding with a heightened state of equilibrium at the end. Think Indiana Jones. You can plug whatever content you want in there as long as it creates the form. Each episode simply has to do with the work of creating disequilibrium.
A narrative does not, in other words, tell a story. A story is told to give listeners the pleasure of the narrative form. If you were to isolate the form of disequilibrium from the specifics of plot, you might arrive at something resembling the collected work of Cindy Sherman. Initially modeled after movie stills, Sherman’s pictures are not, of course, abstract. Over the years, in fact, their content has become increasingly elaborate. I see this as a form of generosity as well as a sign of advanced technical skills. Not since Giuseppe Arcimboldo (1527-1593), perhaps, has an artist contrived to turn the human figure into a more bountiful cornucopia for the eye.
Yet even the most visually splendid of Sherman’s images are minimalist, in that they reduce the narrative down to the precise moment when the center of gravity shifts. Perhaps some unheard word is spoken. A floorboard squeaks. From upstairs comes a thump. And a tentative state of equilibrium gives way to anxiety or dread. That moment, too, represents essence. What more do you need to know
A:a successful film should consist of precise moments B:a tentative state of equilibrium is superior to anxiety or dread C:a reduction is necessary to make the narrative efficient D:a proper moment is enough to achieve narrative purpose
A new kind of radar has been developed for spaceship travelers. A working laboratory model of a new system of radar that makes use of a beam of light is said to be ten thousand times more accurate than the best comparable system of radar that used microwaves.
The model has shown that this radar system, known as laser-doppler radar, can measure with absolute precision speeds varying from spaceship orbital injection (进入) velocities (速度) of five miles per second down to virtual stops—speeds of less than one ten thousandth of an inch per second. According to the scientists who are developing this system, such fine measures of velocity are of prime importance in space missions. In a rendezvous (对接) between two spaceships, or in a landing approach by a vehicle onto an orbiting space station, a bump could rip open a ship’s skin, or a nudge could knock the station out of its orbit.
The light-beam radar, which operates at a frequency of trillions (百万兆) of cycles per second, could easily detect and measure the movement of a vehicle edging up to a satellite space station. A control system using so precise a signal as this would allow a huge vehicle to dock at a space station as lightly as a feather.
A:it is one thousand times more precise than microwave radar B:it provides precise measures of the velocity of space vehicles C:it is a new system of radar D:it can measure the movement of a spaceship less accurately than a microwave radar
A new kind of radar has been developed for spaceship travelers. A working laboratory model of a new system of radar that makes use of a beam of light is said to be ten thousand times more accurate than the best comparable system of radar that used microwaves.
The model has shown that this radar system, known as laser-doppler radar, can measure with absolute precision speeds varying from spaceship orbital injection (进入) velocities (速度) of five miles per second down to virtual stops—speeds of less than one ten thousandth of an inch per second. According to the scientists who are developing this system, such fine measures of velocity are of prime importance in space missions. In a rendezvous (对接) between two spaceships, or in a landing approach by a vehicle onto an orbiting space station, a bump could rip open a ship’s skin, or a nudge could knock the station out of its orbit.
The light-beam radar, which operates at a frequency of trillions (百万兆) of cycles per second, could easily detect and measure the movement of a vehicle edging up to a satellite space station. A control system using so precise a signal as this would allow a huge vehicle to dock at a space station as lightly as a feather.
Laser-doppler radar is especially valuable in space missions because ______.
A:it is one thousand times more precise than microwave radar B:it provides precise measures of the velocity of space vehicles C:it is a new system of radar D:it can measure the movement of a spaceship less accurately than a microwave radar
Passage Five
A new kind of radar has been developed for spaceship travelers. A working laboratory model of a new system of radar that makes use of a beam of light is said to be ten thousand times more accurate than the best comparable system of radar that used microwaves.
The model has shown that this radar system, known as laser-doppler radar, can measure with absolute precision speeds varying from spaceship orbital injection (进入) velocities (速度) of five miles per second down to virtual stops--speeds of less than one ten thousandth of an inch per second. According to the scientists who are developing this system, such fine measures of velocity are of prime importance in space missions. In a rendezvous (对接) between two spaceships, or in a landing approach by a vehicle onto an orbiting space station, a bump could rip open a ship’s skin, or a nudge could knock the station out of its orbit.
The light-beam radar, which operates at a frequency of trillions (百万兆) of cycles per second, could easily detect and measure the movement of a vehicle edging up to a satellite space station. A control system using so precise a signal as this would allow a huge vehicle to dock at a space station as lightly as a feather.
A:it is one thousand times more precise than microwave radar B:it provides precise measures of the velocity of space vehicles C:it is a new system of radar D:it can measure the movement of a spaceship less accurately than a microwave radar
Passage Five
A new kind of radar has been developed
for spaceship travelers. A working laboratory model of a new system of radar
that makes use of a beam of light is said to be ten thousand times more accurate
than the best comparable system of radar that used microwaves. The model has shown that this radar system, known as laser-doppler radar, can measure with absolute precision speeds varying from spaceship orbital injection (进入) velocities (速度) of five miles per second down to virtual stops—speeds of less than one ten thousandth of an inch per second. According to the scientists who are developing this system, such fine measures of velocity are of prime importance in space missions. In a rendezvous (对接) between two spaceships, or in a landing approach by a vehicle onto an orbiting space station, a bump could rip open a ship’s skin, or a nudge could knock the station out of its orbit. The light-beam radar, which operates at a frequency of trillions (百万兆) of cycles per second, could easily detect and measure the movement of a vehicle edging up to a satellite space station. A control system using so precise a signal as this would allow a huge vehicle to dock at a space station as lightly as a feather. |
A:it is one thousand times more precise than microwave radar B:it provides precise measures of the velocity of space vehicles C:it is a new system of radar D:it can measure the movement of a spaceship less accurately than a microwave radar
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