考满分0814起阅读机经 更新时间:2016-08-19 14:17:27

0814点题班·阅读机经
[注] 
1. 以下机经的出场顺序按照本月考场出现频率由高到低排列,靠前的机经出现频率越高,靠后的机经是最近更新机经;
2. 在本次机经整理过程中,发现大多数题目较残,所以主要列出文章内容和结构,希望同学们对整体行文心里有数,上考场仍然要仔细看文章和题目;
3. 考满分机经分为免费版和完整版,完整版阅读机经已经更新至12篇,免费版提供1-6篇。如需完整版机经请联系统战部长报名点题班,除完整版机经外还有直播讲解。


1. 中耳的肌肉
P1 :观点:中耳内的肌肉(middle-ear muscle)/耳膜有两种作用
作用一:减少外部噪音进入内耳,保护内耳免受噪音损害:
中耳内的肌肉虽然是一种骨骼肌(skelton/skeletal bone),但是无法被主动控制(voluntay contract/control),相反是被动应激(reflexive)(让步转折注意出题)。
具体过程:当外界很吵(loud sound) 时,中耳内肌肉会在1/10秒内收缩,阻挡外界通过中耳进入内耳的音量(muffer external voices)。


作用二:保护耳朵,免受头骨对自己声音的传导给耳朵造成伤害:
中耳肌肉除了对外界声音有应激反应,也对人自身发声也有反应:人一旦准备发声,中耳肌肉就会收缩。即使低声说话,中而肌肉也会收缩。
举例:小孩听到自己的声音(比方说自己的哭声),音量可以很大,大到像火车(train)声音一样(effect)(注意类比,可能出题)。


P2 :观点:中耳肌肉对不同频率的声音,反应不同。
中耳肌肉并非完全无偏向性地对于减弱音量(dampen):
中耳肌肉对低频率的声音会减弱较多;对高频率的声音反而会加强,
因此人可以更容易听清别人说话,且可以边听别人说话边自己说话。


P3 :观点:鸟类中耳肌肉只对内部声音(inner voice)有作用(contract), 对外部声源(external)没有反应。
鸟类自己发出的声音太响,如果中耳肌肉不减弱该声音,对鸟类来说,自己听到的声音
大小接近一架喷气飞机(jet)距离15米左右听到的声音大小。
参考资料:
Modern industry has produced a noisy world. The din of jackhammers, the whine of jet engines and the blare of amplified electric guitars have become all too commonplace. It was therefore considerate of nature to have equipped the human ear with a rather sophisticated noise-reduction system: two small muscles that are attached to the ossicles, the tiny bones that connect the eardrum to the cochlea (the structure that houses the sound-receptor cells). When the muscles contract, they dampen the vibrations of the ossicles, thereby reducing the acoustic signal that ultimately reaches the inner ear.
Although they are skeletal muscles (in fact they are the smallest skeletal muscles in the human body), the middle-ear muscles are not under voluntary control. They contract reflexively about a tenth of a second after one or both ears are exposed to loud external sounds. Indeed, the characteristics of the reflex have become so well known that deviations from the normal response serve as a basis for diagnosing various hearing disorders and neurological conditions.
The muscles of the middle ear contract not only in response to loud external sounds but also immediately before a person vocalizes. This pre-vocalization reflex operates even when one speaks, sings or cries as softly as possible. Yet most evidence suggests that it is meant to protect the inner ear from the fatigue, interference and potential injury caused by one's own louder utterances, which can result in high sound levels in one's head. The shouting and wailing of children or babies, for example, can reach their own ears with the same intensity as the sound of a train passing nearby.
The middle-ear muscles do more than just indiscriminately attenuate internal or loud external sounds in humans. The muscles muffle primarily a loud sound's lower frequencies, which tend to overpower its higher frequencies. The net result of this frequency selectivity is to improve hearing-particularly of those sounds that contain many high-frequency components, such as human speech. In fact, the middle-ear muscles are what enables one to hear other people talking even while one is speaking. Among lower vertebrates, birds possess the most elaborate systems for hearing and sound communication. In each ear they have a stapedius analogue, which is attached to both the tympanic membrane and a single ossicle, the columella. Because a bird's stapedius muscle lies mainly outside the middle-ear cavity, it can be studied more readily than the stapedius of mammals without damaging the delicate middle-ear structures.
2. 投资回报率(ROI)
传统方法(measure):注重投资收益率(ROI)会导致只能短期利益(short-term profit)。
投资收益率(ROI)是用来衡量公司表现(performance)的指标。现在的企业比较重视报酬率,美国很多企业用投资回报率(ROI)来衡量投资的收益,并决定是否要投资。但是ROI容易忽略在研发 初期投入高收益低,只有长期投入才会有很好收益的项目。由此导致过于重视在短期的表现,而 不重视研发、长期投资及人才培养。这样会使得社会没有进步的动力,并且很多采用ROI评估的 公司利润都下降,因为ROI的标准是追求短期利益。
结论:R〇I太短视,会因此失去市场份额 (market share)。
新方法:应该注重市场占有率(enlarge market share),则能长期利益。
作者认为,在高度商业化社会,公司应该更关注最大化股价(enlarge market share)/公司不应该 光追求短期利益(short-term profit),市场份额(market share)更重要,因为市场占有率的变动 可以真实反映市场需求了解顾客想法,利于企业作长期规划。在现在的经济环境下,会更有优势 /不重视市占率,即使有优势,也会渐渐被对手超过。新的方法更重视企业的健康发展,而不会使 得企业因为只是追求短期的投入而失去的更广阔的发展空间。
【考古】
衡量公司performance的指标,总说ROI(投资收益率)比较好,就是说现在美国很多公司还是用RIO来衡量公司的表现,只图短期利益的。现在的企业比较重视报酬率, 美国很多企业用投资回报率来衡量投资的收益,并决定是否要投资.但是这个标准忽略了在研发等起初高投入收益低,只有长期投入才会有很好收益的项目,那么导致过于重视在短期的表现,而不重视研发、长期投资及人才培养。因此,使得社会没有进步的动力,并且很多采取ROI的公司利润都下降,因为ROI的标准是能捞一笔捞一笔,追求短期利益,于是发现这个指标太短视,因此失去market share。 但作者认为在高度商业化社会,建议公司更关注最大化股价。要用提出另个策略以股价的长期走势为目的才行,公司不应该光追求短期利益,市场份额market share更重要。在现在这样的经济环境下,更有优势。作者观点很明确,赞成后者。作者认为企业要重视的应是市占率,市占率的变动可以真实反映市场需求了解顾客想法,利于企业作长期规划。不重视市占率,即使有优势,也会渐渐被对手超过。因此,现在提倡用另外一个measure来衡量,新的方法更重视企业的健康发展,而不会使得企业因为只是追求短期的投入而失去的更广阔的发展空间。


3. 共同基金(mutual fund)
PI:共同基金不如指数基金。
市面上有很多共同基金(mutual funds),他们的资金回报率/投资收益率减去管理费 (management fee)和佣金(commission)后往往低于(not outperform)股票市场(index stock market)的回报率/低于市场收益率和指数(index)收益率(profitable)。
解释:指数型(index)基金公司就是用投资人的钱去买和股票市场绑定的指数型股票/基金投资收 益主要依赖指数衡量(track index),而衡量一个基金经理主要是看他的指数股票组合(index)。 指数型基金公司一旦买定就不动了/被动管理,不用支付手续费/管理费少,收益率高。而共同基 金(mutual funds)经常买进卖出(active manage),要支付高额的手续费(fee),所以回报率低/没 优势。
P2:更好的投资方式未被推广。
人们还是会购买共同基金/这些收取高额管理费的共同基金往往还会受到市场的青睐,因为他们号 称拥有一批很强的基金经理(manager),过去的投资表现都非常好(historical/past investment performance)。然而,过去的收益和未来的收益没有关系(but the history cannot predict the future),且一旦经济危机/经济形势转变,损失会非常大。
现在市面上有一种电脑自动管理/绑定的基金(unmanaqed funds),可以植入/自动参照那些基金 经理成功的投资策略(investment strategy)进行投资,且只收取很低的管理费(it's automatically applying mutual fund strategies of those sucessful managers, but the management fee is lower)。这本来是一种很好的概念,很主动(active strategy)收益也很高, 但很少有投资者愿意投资。
原因:
(1)人们已经形成了高额管理费意味着高额投资回报的观念;
(2)基金公司(intermediate)因为这些基金只收取低管理费所以不愿意/没有动力(incentive) 推广这些基金(this type of mutual fund is not well publicized because the income is low, managers are not motivated to promote)。
因此该方法没有被推广。


4. 火星上的水
P1:”水在火星形成过程中是否扮演重要角色?”是颇具争议性的问题。
有一系列证据(evidence)证明,水对于火星的形成影响重大/火星上曾经有水/现在的火星上没有水,但存在大量水的痕迹。这些水的痕迹是由于各种原因而来的
举例说明:
(1) 火星表面有河流(channel)/火星上的河流跟地球上的河流在很多方面不一样(shorter, lower density),但是支流(branch)的形状是个样的。那么这些河道形成的因素可能也是个样的。
(2) 科学家在火星两极发现了类似冰(ice)的东西。
(3) 火星上有很多洪水(flood)过后的痕迹/有流体(fluid)作用的痕迹/有水(water)冲刷的痕迹,
科学家认为洪水(flood)来自地下(subsurface)(Q4)。
P2:再举例说明:
火星上发现的干枯了的河谷(valley),很深的类似西非大裂谷,像是水长时间侵蚀(erosion)造成 的/一般都是水长时间流过才能产生的,又一次表明水的重要性。
但是,适宜的温度是水存在的必要条件/据此推断火星应该曾经很温暖(must be warm and wet enough to support running water)。然而,目前没有任何证据(model)证明火星上能够形成足 够温暖(warm)的大气/火星太冷不可能有液态水。
总结:因此,很多研究者认为火星有水的这个结论可能有误/要么是已经建立的火星气候模型 (model)错了,要么是这些河道不是由水形成的。
【考古】
P1:现象,金星陨石坑(Crater)比较少。
科学家预测金星上应该有很多的大于某个具体面积的Craters(陨石坑),因为金星的大气层比较厚,只有大的陨石才能穿透大气层掉到金星表面上。然而,根据某M探测器的证据显示,金星上的陨石坑数量远低于科学家预测的数目(Q1)。初步的解释是因为进行上一个大型地理运动。
P2:两个人提出理论解释原因。
观点:金星受到风化和水蚀的影响,和地球类似。说是因为金星上的风化和水蚀(water & wind)使陨石坑消失了,其理论依据是地球上的陨石坑也不多,就是因为这个原因。
但是,有证据表明这个理论并不能解释此现象。因为金星上并没有如地球上有的水和风。
P3:Philip提出另外一个解释反驳观点,但也有不足。
Philip不同意拿地球和金星比,因为金星地表温度高没水且仅有微风,他估计是因为火山爆发(?)/毁灭腐蚀(?) 但是他的观点也有缺陷:与在金星上观察到的地表痕迹不符。


5. 鸟类学舌
P1:背景信息引入
PlzStarling叫声音域很宽(compass),甚至能够模仿(mimic & vocalize)人说话。但是因为野外的 Starling 成群结队,叫得太多,太频繁,以至于科学家很难研究这种鸟。
P2:最近新发现
科学家发现可以从starling模仿(mimic)不同的声音(voice)来研究它们的生活习性 (social)。他们把一些Starling抓回实验室,给不同的人养:Range from有人不怎么跟它说话 to有人每天跟它说很多话。
【version1】
谁说话多,鸟就跟谁学说话(vocalize)学得更多,表明鸟对环境有兴趣;
【version2】
鸟根据沟通频率来学舌,越跟你熟越会学你说话。
研究还显示,Starling学人说话爱学短语(discourse & phrase),不爱单学单词。
P3:根据这个研究,科学家判断Starling学人说话是跟父母和同窝的兄弟姐妹们学的,因为它小时候在窝里待很久,和父母以及同窝的兄弟姐妹们接触最多。被关在笼子里后,主人的地位取代了父母或兄妹的地位,于是它就跟人学说话了。
【参考文献】
Social influences on vocal development (@ Cambridge University Press 1997)
Author: Charles T. Snowdon, Martine Hausberger
The vocal talent of starlings has been known since antiquity, when Pliny considered their ability to mimic human speech noteworthy. Ornithologists know that this species possesses a rich repertoire of call and songs, composed of whistles, clicks, snarls, and screeches. In addition, starlings are well known for their ability to mimic the sounds of other animals or even mechanical noises. Descriptions of starling song in the past reflect the difficulty of describing all the variety of sounds included. Witherby mentioned a "lively rambling melody of throaty warbling, chiring, clicking and gurgling notes interspersed with musical whistles and pervaded by a peculiar creaking quality."
This complexity explains why detailed studies of starling song have delayed long after the arrival of the sound spectrograph. As mentioned by West & King, "the problem with starlings is that they vocalized too much, too often and in too great numbers, sometimes in choruses numbering in the thousands. Even the seemingly elementary step of creating an accurate catalogue of the vocal repertoire of wild starlings is an intimidating task because of the variety of their sounds."
Chaiken have compared the sons of young males raised in different social conditions: either with a wild-caught adult song tutor, individually housed but tape-tutored by a tape-recording or raised in total isolation. All birds had been taken from the nest at an early age (8-10 days) and were hand raised. Untutored birds produced mostly an abnormal song, where even the basic organization of song was missing. In contrast, both tape- and live-tutored birds developed songs with a normal basic organization, but with some syntactical abnormalities for the tape-tutored birds. Tape-tutored birds had repertoires half as large as those of live-tutored birds. Large differences occurred between both groups of birds in their …
6. 月球的形成假说
P1:早在Apollo登月之前,就对月球的形成有三种学说:
(1)分裂说fission:地球甩出去的
(2)同源说concurrence:和地球一起形成的
(3)俘获说capture:独立形成
P2:登月后采集了样本数据和研究成果,发现三种说法都错:
(1)假设:如果是fission,crater应该很厚。但是……:反分裂;
现在的地月系统应该转得更快(spin)。但是……:反分裂;
应该还有很多小的卫星体在地球周围。但是……:反分裂;
(2)假设:如果是capture,月亮这个独立的星体应该运动的很慢,才会落入地系:反俘获;
(3)假设:如果是concurrence,它应该具有和地球类似的组成,但是发现……:反同源;
(2)证据:月球上的活泼金属(volatilemental)比如锌铅(zinc, lead)含量比地球少很多:反分裂、同源;
(4)证据:月球core size很小,和地球不像,也不可能独立小星星:反同源,俘获;(Q4) 
P3:提出新理论:collision学说。
(1)活泼金属少:因为地球和另一个宇宙中的物体擦肩而过,温度高而挥发;
(2)core小:因为撞偏了;
(3)转速:因为有角度撞击,所以变慢了。
【参考文献1】
Several mechanisms have been historically proposed for the Moon's formation 4.527 ± 0.010 billion years ago, some 30–50 million years after the origin of the Solar System.[15] These include the fission of the Moon from the Earth's crust through centrifugal forces,[16] which would require too great an initial spin of the Earth,[17] the gravitational capture of a pre-formed Moon,[18] which would require an unfeasibly extended atmosphere of the Earth to dissipate the energy of the passing Moon,[17] and the co-formation of the Earth and the Moon together in the primordial accretion disk, which does not explain the depletion of metallic iron in the Moon.[17] These hypotheses also cannot account for the high angular momentum of the Earth–Moon system.[19]
The prevailing hypothesis today is that the Earth–Moon system formed as a result of a giant impact: a Mars-sized body hit the proto-Earth, blasting material into orbit around the proto-Earth, which accreted to form the Moon.[20] Giant impacts are thought to have been common in the early Solar System. Computer simulations modelling a giant impact are consistent with measurements of the angular momentum of the Earth–Moon system, as well as the small size of the lunar core.[21]Unresolved questions are the relative sizes of the proto-Earth and impactor,[20] and how much material from these two bodies formed the Moon. However, recent oxygen isotope composition analysis of the Moon shows its oxygen isotope composition is more similar to the Earth's than this hypothesis would suggest.[22]
The large amount of energy released in the giant impact event and the subsequent reaccretion of material in Earth orbit would have melted the outer shell of the Earth, forming a magma ocean.[23][24] The newly formed Moon would also have had its own lunar magma ocean; estimates for its depth range from about 500 km to the entire radius of the Moon.[23]


【参考文献2】
For a long time, the fundamental question regarding the history of the Moon was of its origin. Early hypotheses included fission from the Earth, capture, and co-accretion. Today, the giant impact hypothesis is widely accepted by the scientific community.


Fission hypothesis
Is the idea that the early Earth, with an accelerated rotation, expelled a piece of its mass was proposed by George Darwin (son of the famous biologist Charles Darwin). It was commonly assumed that the Pacific Ocean represented the scar of this event. However, today it is known that the oceanic crust that makes up this ocean basin is relatively young, about 200 million years old or less, whereas the Moon is much older. This hypothesis cannot account for the angular momentum of the Earth-Moon system.


Lunar capture
This hypothesis states that the Moon was captured, completely formed, by the gravitational field of the Earth. This is unlikely, since a close encounter with the Earth would have produced either a collision or an alteration of the trajectory of the body in question, so if it had indeed happened, the Moon probably would never return to meet again with the Earth. For this hypothesis to function, there would have to be a large atmosphere extended around the primitive Earth, which would be able to slow the movement of the Moon before it could escape. This hypothesis is considered to explain the irregular satellite orbits of Jupiter and Saturn. In addition, this hypothesis has difficulty explaining the similar oxygenisotope ratio of the two worlds.


Co-accretion hypothesis
This hypothesis states that the Earth and the Moon formed together as a double system from the primordial accretion disk of the Solar System. The problem with this hypothesis is that it does not explain the angular momentum of the Earth-Moon system, nor why the Moon has a relative small iron core compared to the Earth (25% of its radius compared to 50% for the Earth).

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