科技英语阅读(EST

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科技英语阅读(EST Reading)课后习题答案

Unit 1 Mathematics

Part I EST Reading

1. Who is Bertrand Russell?

Bertrand Arthur William Russell (b.1872 – d.1970) was a British philosopher, logician, essayist and social critic best known for his work in mathematical logic and analytic philosophy. His most influential contributions include his defense of logicism (the view that mathematics is in some important sense reducible to logic), his refining of the predicate calculus introduced by Gottlob Frege (which still forms the basis of most contemporary logic), his defense of neutral monism (the view that the world consists of just one type of substance that is neither exclusively mental nor exclusively physical), and his theories of definite descriptions and logical atomism. Russell is generally recognized as one of the founders of modern analytic philosophy, and is regularly credited with being one of the most important logicians of the twentieth century.

2. What is Russell’s Paradox?

Russell discovered the paradox that bears his name in 1901, while working on his Principles of Mathematics (1903). The paradox arises in connection with the set of all sets that are not members of themselves. Such a set, if it exists, will be a member of itself if and only if it is not a member of itself. The paradox is significant since, using classical logic, all sentences are entailed by a contradiction. Russell's discovery thus prompted a large amount of work in logic, set theory, and the philosophy and foundations of mathematics.

Section C Post-reading Task

Reading Comprehension

1. Directions: Work on your own and fill in the blanks with the main idea.

Part 1 (Para. 1): Brief introduction to Russell’s paradox

Part 2 (Paras. 2-5): The effect of Russell’s paradox on Gottlob Frege’s system.

Para. 2: Russell’s paradox dealt a heavy blow to Frege’s attempts to develop a foundation for all of mathematics using symbolic logic.

Para. 3: An illustration of Russell’s paradox in terms of sets

Para. 4: Contradiction found in the set.

Para. 5: Frege noticed the devastating effect of Russell’s paradox on his system and inability to solve it.

Part 3 (Paras. 6-8): Solutions offered by mathematicians to Russel’s paradox

Para. 6: Russell’s own response to the paradox with his "theory of types."

Para. 7: Zermelo's solution to Russell's paradox

Para. 8: What became of the effort to develop a logical foundation for all of mathematics?

Part 4 (Para. 9): Correspondence between Russell and Frege on the paradox

Vocabulary and Structure

2. Directions: Complete the sentences with the words given in the brackets. Change the form if necessary.

1) The key to unraveling such apparent paradoxes is to characterize the initial set of possibilities ("initial" meaning before you receive any extra information) and then to eliminate possibilities based on that extra information. (base)

2) Indeed, this separation of meaning is reflected by the definition of "weak" in the OALD, with a 1

distinct sense reserved for its use when pertaining to that of solutions (definition)

3) The resulting radical pollution control programme outlined by Nixon, calling for a 90 per cent reduction in vehicle emissions by 1980, not only led to him being credited (albeit briefly) as policy initiator of an environmental clean-up but also provided him with the chance to deal a blow to one of his most important opponents in the 1972 elections, Edmund Muskie (blow)

4) Singapore's continuing investments in education and training has brought a tenfold increase in our pool of Information Technology professionals and the Singapore worker has been consistently rated by BERI as the world's best in terms of technical skills, attitude and productivity. (term)

5) In this work he was led to topology, a still new kind of mathematics related to geometry, and to the study of shapes (compact manifolds) of all dimensions. (lead)

6) If there is no allowable string which spans the whole graph, then we can search in the same way as described above, but wherever the required path does not exist in the tree, check if that position in the tree is flagged for end-of-word (way)

7) During the past century, steps forward in physics have often come in the form of newly found particles; in engineering, more complex devices; in astronomy, farther planets and stars; in biology, rarer genes; and in chemistry, more useful materials and medications. (form)

8) A second reason for measurements is the more theoretical, put by Love as " the discovery of numerical relations between the quantities that can be measured to serve as a basis for the inductive determination of the form of the intrinsic energy function. " (serve)

9) Thus the optimum conditions for coastal terrace development would seem to be areas with small tidal ranges. Finally, tidal range is an important factor in the generation of tidal currents which may locally become of geomorphological importance (become)

10) The original double entrance doors to the booking hall had been replaced by an utterly incongruous picture window as had adjacent booking hall and waiting room windows. (replace) 3. Directions: Reorder the disordered parts of a sentence to make a complete sentence.

1) A simple way to describe topology is as a 'rubber sheet geometry' — topologists study those properties of shapes that remain the same when the shapes are stretched or compressed.

2) Since the mid-1990s scientists have floated the idea that representations of numeric quantities, whether expressed as digits or as written words, are codified by the parietal cortex, a higher-processing region in the brain located just above the forehead.

3) As activity was monitored, located just above the forehead ,researchers noted changes under the assumption that the brain reduces activity as it becomes accustomed to a stimulus and then reactivates when a novel stimulus is presented.

4) That has not stopped physicists from devising new algorithms for the devices, which can calculate a lot faster than ordinary computers—in fact, exponentially faster, in quite a literal sense.

5) Such a device would be made of metamaterial, a thicket of metal rings or other shapes that bends light in funny ways.

4. Directions: Change the following sentences into nominalized ones.

1) The passage of night could be marked by the appearance of 18 of these stars.

2) The full proof of Fermat's Last Theorem is contained in these two papers.

3) The concept of fixed-length hours, however, did not originate until the Hellenistic period.

4) There is a probability that my first sock is red because only one of the remaining three socks is red.

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5) The importance of accurate data in quantitative modeling is central to using Bayes's theorem to calculate the probability of the existence of God.

Discourse Understanding

1. C. A "3 percent margin of error" means that there is a 95 percent chance that the survey result will be within 3 percent of the population value.

2. E. How is it that a survey of only 1,000 people can reach this level of accuracy?

3. G. The margin of error depends inversely on the square root of the sample size.

4. A. The margin of error is a mathematical abstraction, and there are a number of reasons why actual errors in surveys are larger.

5. F. Finally, the 3 percent margin of error is an understatement because opinions change. Section A Pre-reading Task

1. Who discovered the Mandelbrot set?

This is not a trick question, not easy to answer. Many people including Mandelbrot have laid claim to the discovery.

2. Why was the set named after Benoit B. Mandelbrot?

The set is named after Benoit B. Mandelbrot, a mathematician at the IBM Thomas J. Watson Research Center because he coined the term fractal to describe phenomena (such as coastlines, snowflakes, mountains and trees) whose patterns repeat themselves at smaller and smaller scales.

3. Why has there been so much controversy about who discovered the Mandelbrot set? Mandelbrot claims that he and he alone discovered the Mandelbrot set, but there are other mathematicians who have challenged his claim.

4. What did the challengers say about Mandelbrot’s claim of discovery?

Two mathematicians said that they independently discovered and described the set at about the same time as Mandelbrot did. And another mathematician also asserted that his work on the set not only predated Mandelbrot's efforts but also helped to guide them

5. Why did some professors support Mandelbrot’s claim?

Mandelbrot deserves to have the set named after him, because his efforts brought the set to the attention of both the public and of the pure-mathematics community.

Section C Post-reading Task

Language in Use

1. Match the Chinese in the left column with the English in the right column.

迭代函数iterative function

优先权之争priority battle

分形特征fractal properties

有意义make sense

以越来越小的规模重复同一模式patterns repeat themselves at smaller and smaller scales

混沌理论chaos theory

季刊a quarterly journal

数学界the mathematics community

波纹线crisp lines

会议公报proceedings of a conference

2. Join the following short sentences into longer ones.

e.g. a. A fractal is generally a rough or fragmented geometric shape .

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b. The shape can be subdivided in parts.

c. each part is (at least approximately) a reduced-size copy of the whole, a property called

d. each part has a property of self-similarity.

e.g. A fractal is generally "a rough or fragmented geometric shape that can be subdivided in parts, each of which is (at least approximately) a reduced-size copy of the whole", a property called self-similarity.

1) In addition to coining the term "fractal" to describe objects and surfaces which are irregular at various dimensions of scale, he also introduced such concepts as "fractal dimensions" and the particular fractal known as the Mandelbrot set, frequently represented with the mathematical formula z → z2 + c.

2) It appeared that things were settling into a pleasant and fruitful routine, with his school lessons supplemented by long talks with his uncle about classical analysis, the iterative work of Pierre Fatou and the equally fascinating Julia Sets generated by Gaston Julia

3) Just as the youthful Mandelbrot had passed his college entrance exams by translating algebraic problems into geometrical problems, and solving them by intuitively deducing the "perfected" shape, he here realized there was something deeper, something mathematical, behind these strange patterns.

4) But the beauty in Mandelbrot's models was not that they generated a deceitful randomness, but that they could generate graphed data whose visual pattern accurately mimicked the visual patterns created by real phenomena。

5) But despite being the inspiration for such metaphysics, Mandelbrot, when asked if fractals don't point to a single rule underlying reality, has simply stated, "There is no single rule that governs the use of geometry. I don't think one exists".

3. Translate the sentences into Chinese.

1) He is best known for coining the term fractal to describe phenomena (such as coastlines, snowflakes, mountains and trees) whose patterns repeat themselves at smaller and smaller scales.

他主要是因为用分形这个概念来描述(海岸线,雪花,山脉和树木)等不规则形状等现象而闻名于世,这些不规则形状在越来越小的规模上不断重复同一模式。

2) A closer look reveals that the borders of the set do not form crisp lines but seem to shimmer like flames.

如果再仔细观察,就可以发现集的边界并没有呈波纹线,而是像火焰一样闪光。

3) Krantz introduced a new element into the debate, however, by stating that the Mandelbrot set "was not invented by Mandelbrot but occurs explicitly in the literature a couple of years before the term 'Mandelbrot set' was coined."

但是,克朗兹在这场辩论中引入了一个新东西,他说曼德布洛特集不是曼德布洛特发明的,而是早在“曼德布洛特集”这个术语出现几年以前就已经明确地在数学文献中出现了。

4) Mandelbrot also suggested that even if Brooks and Matelski's publication had preceded his, they still could not be considered discoverers of the set, because they did not appreciate its significance.

曼德布洛特同时也暗示即使布鲁克斯和马特尔斯基的论文先于他发表,但因为他们没有领会到其价值,仍然不能将他们看作是曼德布洛特集的发现者。

5). In response to Hubbard and Douady's charge that he is stingy in granting credit, Mandelbrot says he has also been accused of overcitation.

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对胡巴德和杜阿迪指责他对论文中材料来源的说明上做得非常少,曼德布洛特回应说也有人也指责过他过分引用别人的成果。

4. Translate the sentences into English.

1) 他的生活和工作过程正如使他成名的几何学一样,既不是线性的,也不具备简单的形状。Like the geometry that made him famous, neither his life nor the course of his work was linear or simplistic in shape and form

2) 曼德布洛特说在随后的的两年里他在多个领域中摸索,却没有明显的相联系的线索。Mandelbrot says he spent the next two years groping, exploring first one field and then another, without any clear sense of the connecting thread.

3) 更奇怪的是,他发现噪音周期与清晰传送周期的比率是恒定的,与用于绘制这个现象的时间大小无关。

Stranger still, he found that the ratio of periods of noise to periods of clean transmission remained constant, regardless of the scale of time used to plot the phenomenon.

4) 通过查询一直到1900年的记录,他开始发现了一个令人惊异的模式,这个模式使他明白了他10年前有关线路噪声的研究工作。

Using records dating back to 1900, he began to perceive an astonishing pattern —one that hearkened back to his work on line noise a decade earlier.

5) 尽管就正常销售而言,价格变化是无序的,而且没有人能够预测价格变化的准确数值,但变化本身却遵循着与变化幅度相关的对称模式。

Although price changes were erratic in terms of normal distribution and no one could predict the exact amount of any particular price change, the changes themselves followed a symmetrical pattern with regards to scaling

Unit 2 Physics

Section A Pre-reading Task

Warm-up Questions: Work in pairs and discuss the following questions.

1. What is quantum physics?

Quantum physics is the study of the behavior of matter and energy at the molecular, atomic, nuclear, and even smaller microscopic levels. In the early 20th century, it was discovered that the laws that govern macroscopic objects do not function the same in such small realms.

http://www.77cn.com.cn/od/quantumphysics/p/quantumphysics.htm

2. Do you know anything about dark matter?

Dark matter is a hypothesized form of matter particle that does not reflect or emit electromagnetic radiation. The existence of dark matter is inferred from gravitational effects on visible matter, such as stars and galaxies.

A small percentage of the gravitational effects observed are from visible matter (some estimates are as low as 4% of total gravitational effects). The remaining 96% is presumed to result from dark matter or dark energy, though these terms are somewhat indicative of our ignorance of the exact nature of these unknown quantities, as they have never been directly observed.

One possible candidate for dark matter are theoretical particles known as weakly interacting massive particles (WIMPs), which are being searched for by the Cryogenic Dark Matter Search (CDMS) experiment.

3. What is dark energy?

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Dark energy is a hypothetical form of energy that permeates space and exerts a negative pressure, which would have gravitational effects to account for the differences between the theoretical and observational results of gravitational effects on visible matter. Dark energy is not directly observed, but rather inferred from observations of gravitational interactions between astronomical objects, along with dark matter.

The term "dark energy" was coined by the theoretical cosmologist Michael S. Turner.

4. Have you ever heard of the big bang theory? Can you give an account of it?

The Big Bang is the dominant (and highly supported) theory of the origin of the universe. In essence, this theory states that the universe began from an initial point or singularity which has expanded over billions of years to form the universe as we now know it.

In 1927, Roman Catholic priest and physicist Georges Lemaitre independently calculated the Friedman solution and again suggested that the universe must be expanding. This theory was supported by Hubble when, in 1929, he found that there was a correlation between the distance of the galaxies and the amount of redshift in that galaxy's light. The distant galaxies were moving away faster, which was exactly what was predicted by Lemaitre's solutions.

In 1931, Lemaitre went further with his predictions, extrapolating backwards in time find that the matter of the universe would reach an infinite density and temperature at a finite time in the past. This means the universe must have begun in an incredibly small, dense point of matter - a "primeval atom."

5. How do you understand string theory?

String theory is a mathematical theory that tries to explain certain phenomena which is not currently explainable under the standard model of quantum physics.

String theory was initially developed in the 1970s in an attempt to explain some inconsistencies with the energy behavior of hadrons and other fundamental particles of physics.

As with much of quantum physics, the mathematics that applies to string theory cannot be uniquely solved. Physicists must apply perturbation theory to obtain a series of approximated solutions. Such solutions, of course, include assumptions which may or may not be true.

The driving hope behind this work is that it will result in a "theory of everything," including a solution to the problem of quantum gravity, to reconcile quantum physics with general relativity, thus reconciling the fundamental forces of physics.

Section C Post-reading Task

Reading Comprehension

1. Directions: Work on your own and fill in the blanks with the main idea.

Part 1 (Paras. 1-3): Brief introduction to dark energy

Para. 1: Dark energy is an unexplained force which tugs galaxies away from each other.

Para. 2: Dark energy is somewhat like anti-gravity.

Para. 3: Dark energy is scientists’ hypothetic form of energy to explain the universe’s expansion. Part 2 (Paras. 4-9): The discovery of dark energy: confounding expectations

Para. 4: The discovery of dark energy is a case of science confounding expectations.

Para. 5: Experts expected that gra vity had slowed down the universe’s rate of expansion.

Para. 6: The universe’s rate of expansion was speeding up.

Para. 7: The result was beyond experts’ expectations which caused much nervous laughter. Para. 8: The measurements of supernovae provided the evidence that the universe’s rate of ballooning was speeding up.

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Para. 9: The scientists observed many supernovae at different distances to determine how fast they are speeding away from us.

Part 3 (Paras. 10-13): The rate of the expansion of the universe: shocking results

Para. 10: The rate of the universe’s expansion is accelerating.

Para. 11: More researches done by other experts also show the same results.

Para. 12: Einstein’s cosmological constant has been revived to explain the puzzling findings. Para. 13: The cosmological constant is one of the leading theories to explain the expansion of the universe.

Part 4 (Paras. 14-17): The difference between dark energy and dark matter

Para. 14: The confusion of dark energy and dark matter.

Para. 15: Dark matter is invisible hypothesized form of matter.

Para. 16: Dark matter and dark energy seem to make up most of the mass of the universe. Para. 17: The discovery of dark energy makes some people believe that there are several universes.

2. Directions: Work in pairs and discuss the following questions.

1) What’s dark energy before and after you studied the text?

2) In your eyes, what’s gravity ant anti-gravity?

3) Did gravity slow down the rate of the expansion of the universe? Why or why not?

4) Can you explain Doppler Effect in detail?

5) Do you know any story of Einstein’s cosmological constant?

6) What is dark matter? What’s the difference between dark energy and dark matter?

7) Is it true or false that the universe is formed mainly of dark energy and dark matter? Can you give some evidence?

8) Are you one of the believers in multiple universes? Why?

(Open)

3. Directions: Read the following passage carefully and fill in the blanks with the words you’ve learned in the text.

Dark energy — the mysterious stuff that is stretching space and speeding the expansion of the universe — is said to have been around at least 9 billion years. It is a hypothetical (hypothesized) form of energy, which is somewhat like anti-gravity that draws galaxies away from each other. In the mid-1990s, when astronomers went about measuring the rate of the expansion of the universe, they surprisingly found that the universe’s ballooning was speeding up, which was beyond many astrophysicists’ expectations. Some other researchers also found that the universe is blowing up faster today than at any time in the past. All these puzzles open up an opportunity for some scientists to revive Einstein’s discarded idea —cosmological constant. Though dark energy and dark matter (invisible) are separate entities, people are always confused about them. It seems that dark energy accounts for 74 percent of the universe, while dark matter adds about 22 percent. The discovery of dark energy is bizarre and adds fuel to the fire of believers in multiple universes.

Discourse Understanding

1. F. Smooth muscles — sometimes also called involuntary muscles — are usually in sheets, or layers, with one layer of muscle behind the other.

2. D. Smooth muscles are also found in your bladder.

3. G. The muscle that makes up the heart is called cardiac muscle.

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4. A. Now, let's talk about the kind of muscle you think of when we say "muscle" — the ones that show how strong you are and let you boot a soccer ball into the goal.

5. C. Together, the skeletal muscles work with your bones to give your body power and strength. Section C Post-reading Task

Language in Use

1. Match the Chinese in the left column with the English in the right column.

处理量子信息manipulate quantum information

超导电路superconducting circuit

电荷或通量charge or flux

文字处理word processing

虚拟实验室virtual laboratory

组织制度constituent system

空间分离spatial separation

没有明显的限制with no apparent limit

有待观察remain to be seen

……正在进行中… be under way

2. Join the following short sentences into longer ones.

e.g. a. This allows quantum interference to be exploited.

b. This greatly enriches the kind of information.

c. The information can be represente

d.

e.g. This allows quantum interference to be exploited and greatly enriches the kind of information that can be represented.

1) Researchers realized that, by manipulating quantum systems directly, they could circumvent the hurdles of simulating quantum phenomena using classical computers.

2) There are other, similarly well-structured mathematical problems for which quantum algorithms can yield solutions dramatically faster than can classical computers.

3) What we have is a number of fundamental quantum-algorithm tools that can be widely applied, and we are seeking more such tools.

4) This typically means that we must be able to access and modify the state of individual qubits and qubit pairs without affecting the other qubits — in much the same way as bits in classical computers are manipulated by applying circuit elements that act on one or two bits.

5) Because the physical interactions that underlie the comp utation’s gates depend on parameters that take a continuous range of values, it is generally believed that it is impractical to achieve high accuracy directly.

3. Translate the sentences into Chinese.

1) It can remove the effects of physically reasonable computational errors and decoherence processes, provided that enough of the requirements for building a quantum computer can be met.

如果能够充分满足制造量子计算机所需的条件,量子纠错就能消除物理上合理的计算误差及退相干过程所带来的影响。

2) Although this limit is case-dependent, there is nevertheless a consensus that, for practical scalability, the probability of error introduced by the application of a quantum gate must be less than 0.0001.

虽然这个极限视具体情况而定,但大家达成一个共识:为了实现可扩展性要求,一个量子门8

运用中所产生的错误率必须小于0.0001。

3) Bearing such requirements in mind, one-qubit registers have been demonstrated, and two-qubit registers are close at hand.

满足这些要求的一个量子位的储存器已经面世了,两个量子位的储存器也快了。

4) Many experiments have been performed involving nuclear magnetic resonance (qubits associated with nuclear spins in molecules) and optics (qubits carried by photons).

已经进行了大量实验,包括核磁共振系统(量子位与分子中核自旋相关)和光学系统(用光子实现量子位)。

5) Ideally, all computation would be based on elementary devices whose quantum features could be exploited with few additional resources over those needed to make them compute classically. 理想情况下,所有的(量子)计算应基于一些基本元件,利用这些元件的量子特性所需的额外资源远少于用它们进行经典计算时所需。

4. Translate the sentences into English.

1) 可以说如果没有量子纠缠现象,,就不会有今天所说的量子信息。

We can dare to say, if there were not quantum entanglement phenomena, there would be no quantum information of today.

2) 量子计算机是一种计算装置,直接利用量子力学现象,如叠加和纠缠对数据进行操作。

A quantum computer is a device for computation that makes direct use of quantum mechanicalphenomena, such as superposition and entanglement, to perform operations on data.

3) 1994年,彼得·肖设计了一种量子算法:用6个量子比特来进行一些基本的因式分解。

In1994, Peter Shor devised an quantum algorithm that could use only 6 qubits to perform some basic factorizations.

4) 大致想法是将一条消息拆分成几个单元的二进制数据─ 0与1的字串。

The general idea is to break up a message into blocks of binary data —strings of “0”s and “1”s. 5) 该论文详细讨论了量子逻辑门的基本构造。

The thesis discussed the basic structure of quantum gate in detail.

Unit 3 Network Security

Section A Pre-reading Task

Warm-up Questions: Work in pairs and discuss the following questions.

1. What is the Internet?

The Internet is the world’s largest network of networks. When y ou want to access the resources offered by the Internet, you don’t really connect to the Internet; you connect to a network that is eventually connected to the Internet backbone, a network of extremely fast (and incredibly overloaded!) network components. This is an important point: the Internet is a network of networks -- not a network of hosts.

A simple network can be constructed using the same protocols and such that the Internet uses without actually connecting it to anything else. Such a basic network is shown in Figure3.

Figure 3: A Simple Local Area Network

I might be allowed to put one of my hosts on one of my employer’s networks. We have a number of networks, which are all connected together on a backbone, that is a network of our networks. Our backbone is then connected to other networks, one of which is to an Internet Service

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Provider (ISP) whose backbone is connected to other networks, one of which is the Internet backbone.

If you have a connection “to the Internet” through a local ISP, you are actually connecting your computer to one of their networks, which is connected to another, and so on. To use a service from my host, such as a web server, you would tell your web browser to connect to my host. Underlying services and protocols would send packets (small datagrams) with your query to your ISP’s network, and then a network they’re connected to, and so on, until it found a path to my employer’s ba ckbone, and to the exact network my host is on. My host would then respond appropriately, and the same would happen in reverse: packets would traverse all of the connections until they found their way back to your computer, and you were looking at my web page.

In Figure4, the network shown in Figure3 is designated “LAN 1” and shown in the bottom-right of the picture. This shows how the hosts on that network are provided connectivity to other hosts on the same LAN, within the same company, outside of the company, but in the same ISP cloud, and then from another ISP somewhere on the Internet.

Figure 4: A Wider View of Internet-connected Networks

The Internet is made up of a wide variety of hosts, from supercomputers to personal computers, including every imaginable type of hardware and software.

2. Do you know anything about IP?

IP

As noted, IP is a ``network layer'' protocol. This is the layer that allows the hosts to actually ``talk'' to each other. Such things as carrying datagrams, mapping the Internet address (such as 10.2.3.4) to a physical network address (such as 08:00:69:0a:ca:8f), and routing, which takes care of making sure that all of the devices that have Internet connectivity can find the way to each other. Understanding IP

IP has a number of very important features which make it an extremely robust and flexible protocol. For our purposes, though, we're going to focus on the security of IP, or more specifically, the lack thereof.

Attacks Against IP

A number of attacks against IP are possible. Typically, these exploit the fact that IP does not perform a robust mechanism for authentication , which is proving that a packet came from where it claims it did. A packet simply claims to originate from a given address, and there isn't a way to be sure that the host that sent the packet is telling the truth. This isn't necessarily a weakness, per se , but it is an important point, because it means that the facility of host authentication has to be provided at a higher layer on the ISO/OSI Reference Model. Today, applications that require strong host authentication (such as cryptographic applications) do this at the application layer.

IP Spoofing.

This is where one host claims to have the IP address of another. Since many systems (such as router access control lists) define which packets may and which packets may not pass based on the sender's IP address, this is a useful technique to an attacker: he can send packets to a host, perhaps causing it to take some sort of action.

Additionally, some applications allow login based on the IP address of the person making the request (such as the Berkeley r-commands )[2]. These are both good examples how trusting

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untrustable layers can provide security that is -- at best -- weak.

3. What is Facebook?

Facebook is a social networking website launched in February 2004 that is operated and privately owned by Facebook, Inc., with more than 500 million active users in July 2010. Users can add people as friends and send them messages, and update their personal profiles to notify friends about themselves. Additionally, users can join networks organized by workplace, school, or college. The website's name stems from the colloquial name of books given to students at the start of the academic year by university administrations in the US with the intention of helping students to get to know each other better. Facebook allows anyone who declares themselves to be aged 13 or older to become a member of the website.

4. How do you understand network security?

In the field of networking, the specialist area of network security[1] consists of the provisions and policies adopted by the network administrator to prevent and monitor unauthorized access, misuse, modification, or denial of the computer network and network-accessible resources.

The terms network security and information security are often used interchangeably. Network security is generally taken as providing protection at the boundaries of an organization by keeping out intruders (hackers). Information security, however, explicitly focuses on protecting data resources from malware attack or simple mistakes by people within an organization by use of data loss prevention (DLP) techniques. One of these techniques is to compartmentalize large networks with internal boundaries.

5. Is privacy important? Why or why not?

There are two general reasons why privacy is important.

For the individual, privacy is important. Unnecessary exposure of sensitive personal information not only creates embarrassment but also an invitation for identity thefts. You may have noticed that many web based email systems monitor your messages on a real time basis and show you advertisements. Your personal messages are sent over the Internet through many routers and computers. Many of these network nodes, proxies and computers are capable of actively monitoring your conversation without you noticing it.

For businesses, privacy means a competitive advantage. Companies that have a stronger privacy policy are perceived as more trustworthy and trust is the foundation of contemporary business practices, no matter it is business to consumer (B2C) or business to business (B2B) transactions. Privacy is also for pragmatic purpose. Premature release of proprietary information such as product designs, artworks, press announcements, journals, books, movies, engineering architectures and so forth would lead to loss of business opportunities.

Section C Post-reading Task

Reading Comprehension

1. Directions: Work on your own and fill in the blanks with the main idea.

Part 1 (Paras. 1-3): Brief introduction to current situation of disclosure of personal information Para. 1: The line that separates the private from the public is dissolved.

Para. 2: Personal information disclosure becomes a norm.

Para. 3: Younger members appear comfortable with sharing about anything and even older ones are adjusting to the trend.

Part 2 (Paras. 4-7): Brief introduction to facebook’s members and its features

Para. 4: The composition of facebook’s members.

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Para. 5: Facebook’s members keep increasing as the olders sign up.

Para. 6: Facebook’s members are becoming more gregarious.

Para. 7: The defining of “friend” online becomes simple.

Part 3 (Paras. 8-17): The analysis of facebook’s service on protection of person al information Para. 8: The growth of membership and of individual networks seems impervious to gaffes at the company during its brief, five-year history.

Para. 9: Facebook restored the old language and offered some changes for ratification.

Para. 10: Facebook offers members a lot of privacy options.

Para. 11: But Facebook sets few restrictions by default on what third-party software can see in a network of friends.

Para. 12: David E. Evans wishes that Facebook would begin with more restrictions on the information that outside software developers can reach.

Para. 13: David E. Evans said that Facebook could set defaults erring on the side of privacy. Para. 14: As a Facebook’s chief privacy officer, Chris Kelly defends its current settings.

Para. 15: David E. Evans believed that banishment of malevolent software comes too late. Para. 16: The defaults turn out to be crucially important.

Para. 17: Users are unwilling to take troubles to customizing permission.

Part 4 (Paras. 18-19): The vague definition of “friends” and its bad effect

Para. 18: The defining of “friends” for facebook’s members are vague.

Para. 19: The distinguish between private and public becomes pointless since “friends” may be those strangers.

Vocabulary and Structure

2. Directions: Complete the sentences with the words given in the brackets. Change the form if necessary.

1) Many people who have not thought carefully beforehand about learning languages are likely to be carried along by a mishmash of ideas that make little or no practical sense.

许多人在学一门外语前缺乏足够的思想准备,极易被杂乱而无实际意义的念头、假设和习惯所左右。

2) He is hell--bent on having his own way.

他一意孤行

3) But most people would rather see the application take some “good enough” first step and then adjust it to what is desired.

然而大部分人都情愿由软件开始某种足够好的第1步,然后按照自己的需要调整。

4) "Note: sign up on the day MOP/HK$100 per Race using the Express Entry Form - available at the Race Registration at 7:30am."

“注意: 请于当日早上七时三十分于登记地点填写特快报名表,每项赛事参赛费用为澳门币/港币一百元整。”

5) Sometimes when the television set doesn't work, you can fiddle with the wires inside and it comes right.

有时电视机坏了,你拨弄拨弄里面的电路,居然能修好。

6) Instead, we'll try to strip away some of the mystery so often associated with software by discussing the process that a programmer follows when developing one.

本书的意图是通过简单地探讨开发一个程序时程序员应该遵循的过程,从而力求揭示那些常常与软件有关的奥妙.

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