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关键词：英语论文的引述学者的论述引述格式注明引文作者注明卷号
摘要：正确引用作品原文或专家、学者的论述是写好英语论文的重要环节;既要注意引述与论文的有机统一,即其逻辑性,又要注意引述格式 (即英语论文参考文献)的规范性)。
引述别人的观点,可以直接引用,也可以间接引用。无论采用何种方式,论文作者必须注明所引文字的作者和出处。目前美国学术界通行的做法是在引文后以圆括弧形式注明引文作者及出处。现针对文中引述的不同情况,将部分规范格式分述如下。
1.若引文不足三行,则可将引文有机地融合在论文中。如:
The divorce of Arnold's personal desire from his inheritance results in “the familiar picture of Victorian man alone in an alien universe”(Roper9).
这里,圆括弧中的Roper为引文作者的姓(不必注出全名);阿拉伯数字为引文出处的页码(不要写成p.9);作者姓与页码之间需空一格,但不需任何标点符号;句号应置于第二个圆括弧后。
2.被引述的文字如果超过三行,则应将引文与论文文字分开,如下例所示:
Whitman has proved himself an eminent democratic representative and precursor, and his “Democratic Vistas”
is an admirable and characteristic
diatribe. And if one is sorry that in it
Whitman is unable to conceive the
extreme crises of society, one is certain
that no society would be tolerable whoses
citizens could not find refreshment in its
buoyant democratic idealism.(Chase 165)
这里的格式有两点要加以注意。一是引文各行距英语论文的左边第一个字母十个空格,即应从第十一格打起;二是引文不需加引号,末尾的句号应标在最后一个词后。
3.如需在引文中插注,对某些词语加以解释,则要使用方括号(不可用圆括弧)。如:
Dr.Beaman points out that“he [Charles Darw in] has been an important factor in the debate between evolutionary theory and biblical creationism”(9).
值得注意的是,本例中引文作者的姓已出现在引导句中,故圆括弧中只需注明引文出处的页码即可。
4.如果拟引用的文字中有与论文无关的词语需要删除,则需用省略号。如果省略号出现在引文中则用三个点,如出现在引文末,则用四个点,最后一点表示句号,置于第二个圆括弧后(一般说来,应避免在引文开头使用省略号);点与字母之间,或点与点之间都需空一格。如:
Mary Shelley hated tyranny and“looked upon the poor as pathetic victims of the social system and upon the rich and highborn...with undisguised scorn and contempt...(Nitchie 43).
5.若引文出自一部多卷书,除注明作者姓和页码外,还需注明卷号。如:
Professor Chen Jia's A History of English Literature aimed to give Chinese readers“a historical survey of English literature from its earliest beginnings down to the 20thcentury”(Chen,1:i).
圆括弧里的1为卷号,小写罗马数字i为页码,说明引文出自第1卷序言(引言、序言、导言等多使用小写的罗马数字标明页码)。此外,书名 A History of English Literature 下划了线;规范的格式是:书名,包括以成书形式出版的作品名(如《失乐园》)均需划线,或用斜体字;其他作品,如诗歌、散文、短篇小说等的标题则以双引号标出,如“To Autumn”及前面出现的“Democratic Vistas”等。
6.如果英语论文中引用了同一作者的两篇或两篇以上的作品,除注明引文作者及页码外,还要注明作品名。如:
Bacon condemned Platoas“an obstacle to science”(Farrington, Philosophy 35).
Farrington points out that Aristotle's father Nicomachus, a physician, probably trained his son in medicine(Aristotle 15).
这两个例子分别引用了Farrington的两部著作,故在各自的圆括弧中分别注出所引用的书名,以免混淆。两部作品名均为缩写形式(如书名太长,在圆括弧中加以注明时均需使用缩写形式),其全名分别为 Founder of Scientific Philosophy 及 The Philosophy of Francis Baconand Aristotle。
7.评析诗歌常需引用原诗句,其引用格式如下例所示。
现如今，大家都知道论文撰写论文内容的教程都比较枯燥，针对性不强，一般不能满足学院英语论文课程的要求，需要教师根据学生的专业特点，依据写作教学规律，自行编写教材。下面是学术参考网小编为朋友们搜集整理的英语论文致谢信，欢迎阅读！
Acknowledgements
MydeepestgratitudegoesfirstandforemosttoProfessoraaa，mysupervisor，forherconstantencouragementandguidance.Shehaswalkedmethroughallthestagesofthewritingofthisthesis.Withoutherconsistentandilluminatinginstruction，thisthesiscouldnothavereacheditspresentform.
Second，IwouldliketoexpressmyheartfeltgratitudetoProfessoraaa，wholedmeintotheworldoftranslation.IamalsogreatlyindebtedtotheprofessorsandteachersattheDepartmentofEnglish：Professordddd，Professorssss，whohaveinstructedandhelpedmealotinthepasttwoyears.
Lastmythankswouldgotomybelovedfamilyfortheirlovingconsiderationsandgreatconfidenceinmeallthroughtheseyears.Ialsoowemysinceregratitudetomyfriendsandmyfellowclassmateswhogavemetheirhelpandtimeinlisteningtomeandhelpingmeworkoutmyproblemsduringthedifficultcourseofthethesis
Fan Zhang
University of Limerick
MEng. Computer and Communication Systems
ID: 0526401
Abstract: I am a video game fan, but not an addict. Since this topic attracted me a lot, I decided to choose this one as my topic for the third assignment of Processor Architecture Module. I started to play video games since I was five. While I was playing games, I found the game console itself just like a mystery, how could they react our actions to the controller then reflects so amazing pictures on TV? Although I have read a lot about it in game magazines, I admit that I didn’t try to find the answer until I found this topic. This is a great chance for me to answer the question myself. At the same time, I want to present you this paper, which should be fun.
This paper concerns the differences of architecture between PC and PlayStation 2. Since the purposes of PC and PlayStation 2 are different (or maybe I should say the purposes of PC include that of PlayStation 2), the different objectives decide the different design orientation. I think PlayStation 2 is a good game console for the comparison. First, a lot of documentations about PlayStation 2’s Emotion Engine can be found in the Internet. Second, as far as I know, PlayStation 2’s design has straightforward purposes: 3D games and multimedia, which makes the game console is seemed to be born for these two reasons. Contrasts to PlayStation, current PCs do very well on these two aspects, but the cost is the unstoppable upgrade of hardware. PlayStation 2 is a product born 5 years ago. Today tens of millions of people are still enjoy PlayStation games at home. 5-year-old PCs have been washed out already.
Keywords: PC, processor, video card, system controller, bus, Emotion Engine, Vector Unit, Graphics Synthesize.
1. INTRODUCTION
1.1 The evolution of game performance
The computer technology has achieved rapid evolution this year. From Figure 1.1 to Figure 1.5 you can see, in almost twenty years, how great changes of game performance are, both PC and game consoles.
Figure 1.1: Final Fantasy I (FC) 1987 by SQUARE
Figure 1.2: Final Fantasy XII (PlayStation 2) 2006 by SQUARE ENIX
Figure 1.3: Prince of Persia (PC) 1989 by Broderbund
Figure 1.4 Prince of Persia: The Two Thrones (PC) 2006 by Ubisoft
The screenshots above are the evidences of technique developments. In these twenty years, computers are almost 10 times faster than in the 1980’s. The cost of buying a computer is decreasing simultaneously. However, the development orientations of both PC and game consoles didn’t change much during these 20 years. Here I want to say game consoles and PC are different, although they both can be classified to ‘computer’ class, although PC includes all game consoles’ functions (but the software are not compatible each other). The differences include many areas, the architecture, the media, the software producing and selling model, and the customers.
1.2 Why they are different?
I would rather to say it is because of the distinct purposes. Of course PC can play games, can do anything that game consoles do, and in the present, PlayStation 2, the most famous game console in the world, can connect to Internet, can print paper, even can run complete Linux operating system, but PC is general purpose, this means PC should care too much things, and be good at almost everything. For instance, PC should be good at text processing, games, printing, Internet connection, a huge amount of protocols are settled for it; PC also need to compatible with all components and software that are designed and implemented by current standards. But game consoles are different. They need only care about games, which mean most designs are flexible. At the same time, the standards which PC has to obey do not affect it at all. No extra cost, no burden, only focus on games.
Figure 1.5: Sony’s PlayStation 2
1.3 Multimedia
From later 20th century, multimedia has become one of the main purposes of PC. Corresponding new technology for enhancing the capability of multimedia processing on PC has been developed as well. However, the reality of transmission speed bottleneck hasn’t been changed much. Keith Diefendorff and Pradeep K. Dubey published an article named “How Multimedia workloads will change Processor Design” in 1996. They argued the dynamic media processing would be a big challenge for current processor architecture. They also thought it will force the fundamental changes in processor design.
Before Pentium 4, the processors shared the same character: their data cache memory was big, but instruction cache memory was relatively small. It was quite useful for most usage, for instance, word editor, e-business, stock information processing, and so on. However, Diefendorff did not think it is useful, or efficient enough for multimedia processing, for multimedia data come and forth constantly, no need to settle a huge bulk of storage space for holding the information that rarely has chance of reuse. Contrarily, multimedia processing requires more calculation than others. So, for multimedia calculation, the instruction cache memory should become larger, both caches require faster transmission speed as well. We shall see this prediction has realized much in both Pentium 4 and PlayStation 2.
1.4 The purpose and the brief layout of the article
This paper is mainly talk about the architectural differences between PC and PlayStation 2, which is the most famous game console in the world. The article will discuss several aspects, the whole architecture, the CPU, the motherboard, and the graphics. In the following section, the whole architectures are compared. Two processors, Intel’s Pentium 4 and PlayStation 2’s Emotion Engine are discussed and compared in the third section. The fourth section is about the bus and caching comparison. The fifth section mainly talks about PC and PlayStation 2’s graphic devices, Video card and Graphics Synthesizer. The conclusion will be made in the last section.
2. WHOLE ARCHITECTURE COMPARISON
2.1 PC architecture
The basis of PC could root back to 1940’s. John von Neumann (1903-57), who constructed a very basis structure of computer, stayed his name in the history forever. The architecture of modern PC is still based mainly on his architecture. Let’s see a diagram of PC architecture as our basis of illustrating how PC works for game performance in the future.
Figure 2.1: PC architecture--------------------------------->
Different regions in the diagram have different clock speed. We can see the system controller is the heart of whole PC system. It carries data between processor and other components in PC over bridge. The bridge is used to connect interfaces and buses. Two kinds of bridges exist in PC, North Bridge (the system controller) and south bridge (the bus bridge). The system controller provides an interface between the processor and external devices, both memory and I/O. The system controller works with the processor to perform bus cycles.
From the diagram we can see, the system controller makes the whole diagram to be complicated. This is because the system controller has to adjust the bus cycles between the processor and the external device that it wants to access. Briefly, the PC’s working procedure can be described as follow:
PC executes commandsèaccess data with the help of system controllerèreturns the execution resultèexecute commandsè…
System controller also possesses the function of controlling DMA (Direct Memory Access), which is the ability to transfer data between memory and I/O without processor intervention.
2.2 PlayStation 2 Overview
Let’s first see the architecture of PlayStation 2.
Figure 2.2: the architecture of PlayStation 2---------------->
PlayStation 2 is composed of a graphics synthesizer, the Emotion Engine, the I/O Processor (IOP), and a Sound Processor Unit (SPU). The IOP controls peripheral devices such as controller and disk drive and detect controller input, which is sent to the Emotional Engine. According to this signal, the Emotional Engine updates the internal virtual world of the game program within the video frame rate. Many physical equations need to be solved to determine the behavior of the character in the game world. After this is determined, the calculated object position is transformed according to the viewpoint, and a drawing command sequence (display list) is generated. When the graphics synthesizer receives the display list, it draws the primitive shape based on connected triangles on the frame buffer. The contents of the frame buffer are then converted from digital to analogue, and the video image appears on the TV. Finally, the Sound Processor is in charge of sound card thing, it outputs 3D digital sound using AC-3 and DTS. This is the overview of PlayStation 2 working procedure.
2.3 Comparison
Compare Figure 2.1 and Figure 2.2, we can see that the PC’s architecture is far more complex than that of PlayStation 2’s. There are many reasons. PC has more devices has to care. For instance, PlayStation’s I/O processor, which is act as the same role as the system controller bus in PC, the chief responsibility of this chip is to manage the different devices attached to the PS2. 2 PlayStation controller port, and MagicGate-compatible memory card interface, 2 USB ports, and a full-speed 400Mbps IEEE 1394 port, which are much less than PC. The other main reason is processor’s speed increased much faster than other devices; the devices themselves had uneven speed increments as well. In general, PlayStation 2 has simpler architecture and less components and devices.
3. ALL ABOUT PROCESSORS
3.1 Pentium 4 Processor
Pentium 4 adopts Intel’s 7th generation architecture. We can see in detail from the diagram below. Since the birthday of PlayStation 2 waiting for exploring was 4th March 2000, when Pentium 4 was not published yet. It is unfair to PlayStation 2. However, Pentium 4 is the most popular processor in the present, and PlayStation 2 is globally the most popular game console, whatever.
Figure 3.1: Pentium 4 processor architecture
Since the previous generation architecture (Pentium III) Intel began to use hybrid CISC/RISC architecture. The processor has to accept CISC instructions, because it has to be compatible with all current software (most software is written using CISC instructions). However, Pentium 4 processes RISC-like instructions, but its front-end accepts only CISC x86 instructions. A decoder is in charge of the translation. Intel doesn’t create the path for programs using pure RISC instructions.
CISC instructions are rather complex, decoding one may cost several clock cycles. In Pentium III era, once a CISC instruction needed to be processed several times (i.e. a small loop), the decoder had to decode the instruction again and again. In Pentium 4 this situation has been improved by replacing Pentium III’s L1 instruction cache to Trace Cache, which is placed behind the decoder. The trace cache ensures that the processor pipeline is continuously fed with instructions, decoupling the execution path from a possible stall-threat of the decoder units. After decoding stage, Intel introduces the Renamer/Allocator unit to change the name and contents of 32-bit CISC instructions of the registers used by the program into one of the 128 internal registers available, allowing the instruction to run at the same time of another instruction that uses the exact same standard register, or even out-of-order, i.e. this allows the second instruction to run before the first instruction even if they mess with the same register.
The other big advance of Pentium 4 is its SSE2 - The New Double Precision Streaming SIMD Extensions. 128-bit SIMD package offers 144 strong instructions. Intel prepares two SIMD instruction units for Pentium 4 (64-bit each), one for instructions, and the other for data. Let’s recall Section 1.3, Pentium 4’s 128-bit SIMD extension is Intel’s efforts for meeting the future requirements for multimedia implementations. Because of that, video, games implementation capability gained the drastic enforcement.
Pentium 4’s pipeline is the most disputable place. When it was announced, 20-stage pipeline surprised a lot of people. Intel did so because the more stage pipeline can increase the clock rate of processor. However, once the pipeline does not contain the information what processor need, the pipeline refill-time is going to be a long wait. In fact, Pentium 4 is only faster than Pentium III because it works at a higher clock rate. Under the same clock rate, a Pentium III CPU would be faster than a Pentium 4.
Figure 3.2: Pentium 4 Pipeline
The scheduler is a heart of out-of-order engine in Pentium 4. It organizes and dispatches all microinstructions (in other words, uops) into specialized order for execution engines.
Figure 3.3: Pentium 4 scheduler
Four kinds of schedulers deal with different kinds of microinstructions for keeping the processor busy all the time. The ports are Pentium 4’s dispatch ports. If you read the diagram carefully, you can see Port 1 and Port 0 each is assigned a floating-point microinstruction, Port 0 is assigned Simple FP Scheduler (contains simple Floating-point microinstructions) and Port 1 is assigned Slow / Floating Point Scheduler (contains complex floating-point microinstructions). Port 0 and Port 1 also accept the microinstructions came from Fast Scheduler. For the floating point microinstruction may run several clock cycles, Pentium 4’s scheduler monitor decides to transfer the microinstruction to Port 1 if Port 0 is busy, and vice versa. Port 2 is in charge of Load microinstructions and Port 3 deals with Store microinstructions.
3.2 PlayStation 2’s Emotion Engine
PlayStation 2’s designers focus deeply on the purpose of 3D games. At the same time, they had to ensure it was completely compatible with DVD video. For performing 3D games well, PlayStation 2 has to possess perfect vision and audio functions. Emotion Engine acts as the role of Geometry calculator (transforms, translations, etc), Behavior/World simulator (enemy AI, calculating the friction between two objects, calculating the height of a wave on a pond, etc). It also in charge of a secondary job of Misc. functions (program control, housekeeping, etc). In general, Emotion Engine is the combination of CPU and DSP processor.
Figure 3.4: The architecture of Emotion Engine
The basic architecture of Emotion Engine is show in Figure 14. The units are composed of
(1) MIPS III CPU core
(2) Vector Unit (two vector units, VU0 and VU1)
(3) Floating-Point Coprocessor (FPU)
(4) Image Processing Unit (IPU)
(5) 10-channel DMA controller
(6) Graphics Interface Unit (GIF)
(7) RDRAM interface and I/O interface.
Something interesting in the diagram you may have noticed. First, inside the Emotion Engine, there is a main bus connects all components for data communication. However, between MIP III core and FPU, VU0 and MIP III, VU1 and GIF, there are dedicate 128-bit buses connect them. Second, VU0 and VU1 have certain relationship shown in the diagram. This design extremely enhanced the flexibility of programming with Emotion Engine.
MIPS III Core connects with the FPU and VU0 directly with the dedicated buses. The pipeline of MIPS III is 6-stage. The MIPS III is the primary and controlling part, VU0 and the FPU are coprocessors to MIPS III. They compute the behavior and emotion of synthesis, physical calculations, etc For example, in a football game, the flying orbits of the ball, the wind effect, the friction between ball and the ground need to be calculated. At the same time, 21 player’s AI needs to be implemented (the last player is controlled by the user), the activity, the lineup, etc. After the calculation, MIPS III core sends out the display list to GIF.
VU1 has a dedicated 128-bit bus connected to GIF, which is the interface between GS (Graphics Synthesizer) and EE (Emotion Engine). VU1 can independently generate display list and send to GIF via its dedicated bus. Both of these relationships forms a kind of dedicate and flexible structure. The final goal of EE is generating display list and send to GS. The programmer can choose either programming two groups (MIPSIII + FPU + VU0 and VU1 + GIF) separately, send their display list in parallel, or programming purposely, making MIPS III + FPU + VU0 group as the “coprocessor” of VU1, for instance, generate physical and AI information then send to VU1, VU1 then produces corresponding display list. The diagram below shows the two programming methods.
(a) (b)
Figure 3.5: Two programming methods of Emotion Engine
MIPS ISA is an industry standard RISC ISA that found in applications almost everywhere. Sony’s MIPS III implementation is a 2-issue design that supports multimedia instruction set enhancements. It has
(1) 32, 128-bit general purpose registers
(2) 2, 64-bit integer ALUs
(3) 1 Branch Execution Unit
(4) 1 FPU coprocessor (COP1)
(5) 1 vector coprocessor (COP2)
What I really want to cover are two vector processors, VU0 and VU1. This is the main reason why PlayStation 2 is powerful.
VU0 is a 128-bit SIMD/VLIW design. The main job of VU0 is acting as the coprocessor of MIPS III. It is a powerful Floating-point co-processor; deal with the complex computation of emotion synthesis and physical calculation.
The instruction set of VU0 is just 32-bit MIPS COP instructions. But it is mixed with integer, FPU, and branch instructions. VIF is in charge of unpacking the floating-point data in the main bus to 4 * 32 words (w, x, y, z) for processing by FMAC. VU0 also possesses 32 128-bit floating-point registers and 16 16-bit integers.
VU0 is pretty strong. It is equipped with 4 FMACs, 1 FDIV, 1 LSU, 1 ALU and 1 random number generator. FMAC can do the Floating-Point Multiply Accumulate calculation and Minimum / Maximum in 1 cycle; FDIV can do the Floating-Point Divide in 7 cycles, Square Root in 7 cycles, and Inverse Square Root in 13 cycles. In fact, as the coprocessor of MIPS III, VU0 only uses its four FMACs. However, VU0 doesn’t have to stay in coprocessor mode all the time. It can operate in VLIW mode (as a MIPS III coprocessor, VU0 only takes 32-bit instructions. In VILW mode, the instruction can be extended to 64-bit long). By calling a micro-subroutine of VLIW code. In this case, it splits the 64-bit instruction it takes into two 32-bit MIPS COP2 instructions, and executes them in parallel, just like VU1.
VU1 has very similar architecture than VU0. The diagram below is the architecture of VU1 possesses all function that VU0 has, plus some enhancement. First, VU1 is a fully independent SIMD/VLIW processor and deal with geometry processing. Second, VU1 has stronger capability than VU0: it has a 16K bytes’ instruction memory and a 16K bytes’ data memory, which VU0 only has 4K bytes each. VU1 acts as the role of geometry processor; it burdens more instructions and data to be computed. Third, VU1 has three different paths to lead its way to GIF. It can transmit the display list from 128-bit main bus, just as VU0 + CPU + FPU do; or it can transmit via the direct 128-bit bus between its VIF and GIF; the last one is quite interesting, the path comes out from the lower execution unit (which I will talk about later) and goes directly to GIF. Three individual paths ensure two main problems of PC 3D game programming will not happen: first, the bottleneck of bus bandwidth; second, the simplex way of programming.
Figure 3.6: The architecture of VU1
VU1’s VIF does much more than that of VU0 does. The VIF takes and parses in which Sony called 3D display list. The 3D display list constructs of two types of data: the VU1 programming instructions (which goes to Instruction memory) and the data that the instruction deal with (which goes to Data memory). The instruction itself can be divided into two units, Upper instruction and Lower Instruction, which directly operate on two different execution units, Upper execution unit and Lower execution unit. The 64-bit VLIW instruction can be used to deal with two operations in parallel. Recall that VU0 possesses the same function but most of time it acts only as the coprocessor of MIPS III, this mode can only operate 32-bit SIMD instructions. Programmers also rarely ask VU0 to do the same thing what VU1 is good at.
3.3 Comparison
I strongly agree if you think Emotion Engine is more flexible than Pentium 4. The design of Emotion Engine is completely around the performance of 3D games. Two vector units, VU0 and VU1, contribute a lot for the game performance. Pentium 4 architecture is straight, you can trace the path of data from the very beginning, and soon you will be able to know how Pentium 4 works easily. For Emotion Engine, except you are the game designer, you will never know exactly.
I did not put too much digits in this section, the comparison of digits does not make sense at all. The comparison between two PC processors depends on digits, because they are the same kind and work in the same situation. For game consoles, without the burden of compatibility, the designers think a lot for the perfect cooperation. This would results in better performance, plus less cost. Unfortunately the programmers don’t think it is a good idea, it cost them quite a lot of time to investigate the processor to figure how it works.
4. BUSES AND CACHEING
4.1 PC Motherboard
While multimedia processing requires massive quantities of data to move rapidly throughout the system, the speed difference between processor and external devices is the main bottleneck of PC. Processor companies like Intel have put a lot of energy into getting the rest of the system components to run faster, even if other vendors provide these components. Improving the performance of motherboard is a good idea. Figure 4.1 is the main structure diagram of GIGABYTE GA-8TRX330-L Pentium 4 Motherboard. The bandwidth between Processor and system controller, main memory and system controller has reached to equally incredible 6.4GB/S. However, the latency of memory is still impossible to remove. Here I want to talk something about the processor caching mechanism.
In the present, motherboard’s FSB (Front Side Bus) frequency has over 800 megahertz. However, it is slower than that of Pentium 4, which is over 3 gigahertz. Processor runs at a multiple of the motherboard clock speed, and is closely coupled to a local SRAM cache (L1 cache). If processor requires data it will fist look at L1 cache. If it is in L1 cache, the processor read the data at a high speed and no need to do the further search. If it is not, sadly processor has to slow down to the motherboard clock speed (what a drastic brake!) and contact to system controller. System controller will check if L2 cache has the required data. If has, the data is passed to processor. If not, processor has to access the DRAM, which is a relatively slow transfer.
4.2 About PlayStation 2’s buses and caching.
Recall Figure 2.2, we can see 32-bit interfaces between processor and I/O Processor, main memory and I/O Processor, which can achieve 3.2GB/S bus speed. Although slower than Pentium 4, Emotion Engine itself is relatively slow as well, 300MHz MIPS III processor. However, PlayStation 2’s 32-bit interface, 10-channel DMAC, 128-bit internal bus, and small cache memory group to an incredible caching condition. Any data necessary can be store or download in time. This strategy takes 90% of DMA capability. It makes the latency which main memory generates is acceptable for Emotion Engine.
4.3 Comparison
This time we can talk about digits some more. Let’s see a Pentium 4’s cache memory
L1 trace cache: 150K
L1 data memory: 16K
L2 memory: 256K ~ 2MB total: 422~2204K
Let’s see PlayStation 2 next
VU0 data memory: 4K
VU0 instruction memory 4K
VU1 data memory 16K
VU1 instruction memory 16K
MIPS III data memory: 2-way 8K
MIPS III instruction memory: 2-way 16K total: 64K
Contrast to Pentium 4, the cache memory of PlayStation 2 is too small. Its capability is indeed ‘weak’ in the present. Pentium 4 is able to hold more data and does more computations in parallel. However, PC architecture hasn’t been improved along with the processor. No matter how Pentium 4 fast is, present bus architecture is never going to perform Pentium 4 100% capability. PlayStation 2 achieves a nearly perfect structure and mechanism, which helps it exert as much as it can (or maybe I should say because Pentium 4 is too fast, the memory speed is relatively too slow). Besides, it remarkably low down the cost, you can afford a PlayStation 2 plus a controller with the same price of a single Pentium 4 chip.
5. VIDEO PERFORMANCE
5.1 Comparison of performance between PC and PlayStation 2
Figure 5.1 Need for Speed Most Wanted (PlayStation 2) 2006 by EA GAMES
PlayStation 2 Graphics Synthesizer (GS)
· 150 MHz (147.456 MHz)
· 16 Pixel Pipelines
· 2.4 Gigapixels per Second (no texture)
· 1.2 Gigatexels per Second
· Point, Bilinear, Trilinear, Anisotropic Mip-Map Filtering
· Perspective-Correct Texture Mapping
· Bump Mapping
· Environment Mapping
· 32-bit Color (RGBA)
· 32-bit Z Buffer
· 4MB Multiported Embedded DRAM
· 38.4 Gigabytes per Second eDRAM Bandwidth (19.2 GB/s in each direction)
· 9.6 Gigabytes per Second eDRAM Texture Bandwidth
· 150 Million Particles per Second
· Polygon Drawing Rate:
· 75 Million Polygons per Second (small polygon)
· 50 Million Polygons per Second (48-pixel quad with Z and Alpha)
· 30 Million Polygons per Second (50-pixel triangle with Z and Alpha)
· 25 Million Polygons per Second (48-pixel quad with Z, Alpha, and Texture)
· 18.75 Million Sprites per Second (8 x 8 pixel sprites)
Figure 5.2 Needs for Speed Most Wanted (PC) 2006 by EA GAMES
PC Graphics Chip RADEON X300 SE PCI Express
· Bus type PCI Express (x16 lanes)
· Maximum vertical refresh rate 85 Hz
· Display support Integrated 400 MHz RAMDAC
· Display max resolution 2048 x 1536
· Board configuration
· 64 MB frame buffer
· Graphics Chip RADEON X300 SE PCI Express
· Core clock 325 MHz
· Memory clock 200 MHz
· Frame buffer 64 MB DDR
· Memory I/O 64 bit
· Memory Configuration 4 pieces 8Mx16 DDR
· Board configuration
· 128 MB frame buffer
· Specification Description
· Graphics Chip RADEON X300 SE PCI Express
· Core clock 325 MHz
· Memory clock 200 MHz
· Frame buffer 128 MB DDR
· Memory I/O 64 bit
· Memory Configuration 4 pieces 16M x 16 DDR
· Memory type DDR1
· Memory 128 MB
· Operating systems support Windows? 2000, Windows XP, Linux XFree86 and X.Org.
· Core power 16 W (Max board power)
From the data we can see. GS is too weak, contrast to low-level video card of PC. However, the performance of PlayStation is not too that bad. I don’t want to analyze data here. What I am interested to discuss is about the performance itself.
Let’s see Figure 5.2 in detail. Texture is very clear and exquisite. This is what big video memory offers. The tree leaves in distance need a lot of polygons to build. The video card itself is low-level; possess no special effect for the game rendering. No refection and other sparking place can be found. In general, the game performance is only ok.
Figure 5.3 PC game rendering related architecture
Now let’s see PlayStation 2’s performance, which is in Figure 5.1. We see a good image. If you look the image in detail, you may found the mountain beside the road is weird: the shape of mountain is not that nature, like some spectrum graphics. This is done by VU1, which draws the Bezile, build 3D graphic based on the curve. Although not good enough, how many people will actually notice that when dashing at over 200km/h with his virtual car? VU1 does a lot of job like that and it could generate a lot of shapes without too many polygons to build. Now let’s see the car, the refection of cars is true reflection (which means it is not fake texture pretended to be the reflection), we can distinguish the mountains behind, however very blur. The whole image is not as clear as Figure 5.2 because the limitation of GS’s video memory (4M). However, this image is good enough for most PlayStation 2 players.
5.2 Some more about the video performance
Although Pentium 4 has enough capability to process image real time, the way of implementing games is still no change. The video card read the content of texture into its local memory card, the processor only deal with the data and instructions. After the calculation, the processor stores the display list (a list, recorded with the details of all elements, for instance, one single polygon’s position and texture code) back to the main memory. Video card then access the lists and process them, generate picture, transfer to analogue signal and output. Most special effects depend on the video card. So, no good card, no good performance.
Let’s see figure 2.2, we will see there is no direct connection between GS and main memory. At the PC’s point of view, 4MB video-memory is not enough to show a single frame with 1024*768 pixels. How is PlayStation 2 able to perform like that? The answer is bus. So we come back to section 4 again. The specialized display list (which Sony called 3D display list) is directly sent to GS, along with the required texture. GS has a huge bandwidth (3.8GB/S), its local memory can work as fast as it is (maybe it is more suitable if we call the memory as cache). GS itself supports only a few special effects. However, this situation can be improved by the simulation calculations finished by Emotion Engine… Again, PlayStation 2’s elegant design makes its all components work as a whole.
6. CONCLUSION
Hopefully you have got the idea of how PlayStation 2 and PC architecture differ. Let’s go through it again.
General architecture. PCs are more complex to read, but easier to implement. The system bus directly manages all devices inter-communications. PlayStation 2’s is easy to read, but much harder to implement. The communication between each other is convenient.
Processor architecture. The trend of processor architecture design is meeting the requirement of multimedia. Both PC’s Pentium 4 and PlayStation 2’s Emotion Engine are qualified to run multimedia applications efficiently. Pentium 4 is much stronger than Emotion Engine, but the architecture is very ‘straight’ and has to do extra jobs of translating instructions to be compatible with current applications. Emotion Engine has no this burden, the specialized 3D game performance design make it easy to handle complex calculation jobs with relatively low clock rate.
Buses and Caching. PC has classic bottlenecks and there is no way to overcome it. Current PC buses and cache has improved a lot by increasing the bandwidth and cache volumes, but the latency of main memory cannot be solved. PlayStation 2 works on nearly full load; perfect coordination between components is almost achieved.
Video. Although Pentium 4 can run perfectly on multimedia applications, the PC game developers don’t think so. They still stick to push the texture and other data into the video memory for one time. The awkward situation is, when you want to update your PC for high requirement games, the first component came into your mind must be the video card but processor. It is impossible to ask PlayStation 2 players to update. Emotion Engine is in charge of many jobs what PC’s video card does. The good condition of data transmission makes it is possible to implement ‘true’ multimedia processing in games, that is treating game image as media streams, no need to supply huge data storage to hold that.
Purpose: PC’s general—purpose VS PlayStation 2’s 3D game rendering purpose.
PlayStation 2 is 6 years old now. According to the principle of game console life expectance, it is time to hand the baton to its offspring, PlayStation 3. It is a successful game console of Sony. Contrast to PC, it is too weird, but all its weird compositions seemed so reasonable as well. PC’s architecture is classical; all components have its space for upgrade. Maybe it is too early to say the architecture should evolve. However, PlayStation 2’s architecture gave us a good lesson. If you only were interested in games, you should buy a PlayStation series, not a PC. At least, you need not worry about upgrading your components for the next game. Special architecture can make it becomes the best in specialized region.
7. REFERENCE
[1] William Buchanan and Austin Wilson, “Advanced PC Architecture”, ISBN: 0 201 39858 3
[2] John L. Hennessy and David A. Patterson, “Computer Architecture—A Quantitative Approach”, ISBN: 1 55890 724 2
[3] Keith Diefendorff and Pradeep K. Dubey, "How Multimedia Workloads Will Change Processor Design." Computer, September 1997
[4] Jon "Hannibal" Stokes Sound and Vision: A Technical Overview of the Emotion Engine Wednesday, February 16, 2000
[5] K. Kutaragi et al "A Micro Processor with a 128b CPU, 10 Floating-Point MACs, 4 Floating-Point Dividers, and an MPEG2 Decoder," ISSCC (Int’l Solid-State Circuits Conf.) Digest of Tech. Papers,Feb. 1999, pp. 256-257.
[6] Jon "Hannibal" Stokes “SIMD architectures”
arstechnica.com/articles/paedia/cpu/simd.ars
[7] “Graphics Synthesizer – Features and General Specifications”
arstechnica.com/cpu/1q99/playstation2-gfx.html
[8] “The Technology behind PlayStation 2”
ieee.org.uk/docs/sony.pdf
[9] Michael Karbo,“PC Architecture“
karbosguide.com/books/pcarchitecture/start.htm
[10] Gabriel Torres, “Inside Pentium 4 Architecture”
hardwaresecrets.com/article/235/1
[11] Thomas Pabst, “Intel’s new Pentium 4 Architecture”
tomshardware.co.uk/2000/11/20/intel/
[12] KuaiLeDaYuShu, “Video Card Parameters Analysis”
blog.yesky.com/Blog/joyelm/archive/2005/07/30/253803.html
[13]Howstuffworks “How PlayStation 2 Works”
entertainment.howstuffworks.com/ps21.htm
引言
攀枝花市，四川省唯一以花命名的城市，被称作阳光花城，座落在四川西南角，金沙江和雅砻江交汇处。自1965年建市以来，城市建设已形成规模，旅游资源独具特色：独特的自然地理环境、独具风味的饮食，浓郁的少数民族民俗风情文化，成为独树一帜的旅游品牌，成为攀枝花市对外开放的重要组成部分。
旅游文化的翻译工作是使对外宣传资料发挥作用的重要环节， 也是一个城市对外交流水平和人文环境建设的重要体现。如何让攀枝花走向世界、让世界了解攀枝花， 有效开展招商引资、扩大对外交流和合作起到了积极作用。在这种情况下，针对目前攀枝花市独特旅游资源的英译问题进行分析、研究，将极大地促进攀枝花的对外交流合作和提高城市的整体形象。但是由于中英旅游文本中的文化差异表现在其不同的审美、价值观及风俗习惯等中英旅游文本在提供信息方面亦有不同的侧重点。因此，在功能理论的指导下，结合中英旅游文本的不同点，，旅游文本的翻译应以游客为中心，以传播中国文化为导向，最终达到旅游文本的诱导目的。可以采取相应的翻译策略：直译、增译、省译、类比等，以期增强旅游文本译文的可读性，最终有效实现译文的预期功能和目的。
一、攀枝花特色地理地貌的英译
攀枝花地处攀西裂谷中南段，属浸蚀、剥蚀中山丘陵、山原峡谷地貌，山高谷深、盆地交错分布，地质构造复杂，森林覆盖面积大，喀斯特地貌分布广，裂谷、温泉、溶洞、瀑布和河流比比皆是，为旅游事业的发展提供了资源基础。对于对于攀枝花特色地理地貌的英译方面，张沉香（2007）对于术语的国际化， 提出应“适当加大音译比例”，“促进国际合作和科技发展”。
音译不仅能够达到简洁和透明的作用，还是保存源语文化的最佳途径。尊重术语体现的文化而采用音译的翻译方法也是现代术语翻译的一个趋势。以攀枝花地理地貌“喀斯特”为例，就是采用的音译方法现已被学界多接受，然而它却曾被中国学界采用意译的方法改译为“岩溶”。另一个类似的例子是世纪初由中国学者确定的“天坑”，即西方地理学学术话语中的“特大型塌陷漏斗”所描述的地理样貌，在攀枝花也是数量众多，大小不一。2005 年起，“天坑”这一定名获得了国际喀斯特学术界的一致认可，汉语拼音 “tiankeng”开始国际通用“喀斯特”在中国和 “tiankeng”在国际学界的最终被接受，这体现了两个属于名词文化内涵的保留，以及音译在学术文化界的认同。
攀枝花非常有名的“格萨拉生态旅游区”主景区距泸沽湖116公里，距丽江376公里，沿省道216线（稻攀路）前行可达稻城、亚丁，景区景观由天坑地漏、岩溶景观、高山草甸和彝家风情等组成。关于“格萨拉生态旅游区”的英译资料“Gesala Ecotourism Area as a part of the Golden Triangular Tourism Area of Daocheng， Lijiang and Panzhihua is located at the juncture of Sichuan and Yunnan Provinces.”该译文首先介绍了格萨拉生态旅游区的地理位置位于稻城，丽江和攀枝花旅游金三角，位于川滇两省的交接处。 “ It is not only the south gate of the Great Shangri-la of China， but also an important component of the Sunshine Ecotourism Area in west Panzhihua City.” 此句则强调了格萨拉生态旅游区的重要性，为中国大香格里拉的南大门， “the south gate”则运用了英语中隐喻的修辞手法 “metaphor” ，非常生动形象。
Anothermajorareaofdebateintherealmofmacroeconomicsdealswiththebudgetdeficit.Therearenumerousquestionsthatsurroundthebudgetdeficitdebate.Forinstance,shouldthebudgetbebalanced?Whatistheburdenofthenationaldebt?Whatarethelong-termeffectsofanunbalancedbudget?Theanswerstothesequestionsdivideeconomists.
ThisSparkNotecoverstwomajoreconomicpolicydebatesthatrelatedirectlytomoneyandtotheeconomy.Thesedebatesareimportantsincetheyoftendivideeconomists.Similarly,byunderstandingthesedebates,itispossibletoviewthecomplexityofmacroeconomicpolicyintherealworld.Whilemacroeconomictheoryseemsratherblackandwhite,theapplicationofthistheorytotherealworldisnowherenearthissimple.
TheFedandthegovernmentusedifferenttoolstosteertheeconomy.Recallthatmonetarypolicy,thetoolboxoftheFed,includesperformingopenmarketoperations,andchangingboththereserverequirementandthefederalfundsinterestrate.Recallalsothatfiscalpolicy,thetoolboxofthegovernment,includeschangingbothtaxesandgovernmentspending.
Allofthesetoolscanbecontrolledactively.Thatis,iftheFedorthegovernmentdecidetouseexpansionarypolicy,theycansimplyselectatoolfromthepolicytoolboxanduseit.Inthisway,activepolicyisdefinedasactionsbytheFedorbythegovernmentthataredoneinresponsetoeconomicconditions.Thatis,theFedorthegovernmentchoosetorespondtosomethingintheeconomybyundertakingaspecificpolicy.Thisisalsocalleddiscretionarypolicy.
Activepolicy,whilesimple,isopentoanumberofdifficulties.BecauseitreliesontheactionsandexperiencesofthepolicymakersintheFedandinthegovernment,theweaknessesorprejudicesofthesepolicymakerscanbetranslatedintoofficialeconomicpolicy.Forinstance,duringelectionyears,acentralbankermaypursuepolicythatenablestheeconomytogrowintheshortrun,regardlessofthelong-termeffects,inordertohelpacandidate.Ontheotherhand,thecentralbankermaycontracttheeconomytohurtacandidate.Similarly,itwouldbepossibleforthepolicymakerstopursuepoliciesthatachievetheirselfishendsratherthanthosethatarebestfortheeconomyatlarge.Finally,withactivepolicy,policymakerscansayonethinganddoanother.Theremaybebenefitstomakingthepublicbelievethatsomethingdifferentisoccurringintheeconomyratherthanwhatactuallyisoccurring.Forinstance,iftheFedwantstoincreaseinvestment,itcouldusedeceptionbyclaimingthatitraisedinterestrateswhilenotactuallydoingso.Inthisscenario,privateinvestorswouldsavemorebutinvestmentwouldremainattheoldlevelorevenincrease.Thus,itisreasonabletoclaimthatactivepolicyleavesmonetarypolicyandfiscalpolicyopentonotonlyaccidentalhumanerrorbutalsotomaliciousandself-servingacts.
二、依纲扣本，中考采用三阶段四板块循环滚动的复习模式
根据《英语课程标准》和《英语中考指南》，三阶段指复习时间分为三个阶段，四板块指单元梳理板块、专项训练板块、综合训练板块和听、说、读、写能力训练板块，它们互相融合互相促进，使知识和能力水平不断循环提升。第一阶段单元梳理板块主要是梳理初中阶段所学的全部的语言知识。牛津英语教材按照话题———结构———功能———情景———任务体系以单元形式编排，所以梳理语言知识以单元作板块来整体复习较合理。按教材顺序以话题和任务为主线，以及他们和功能、语法项目的关系提前分门别类的梳理，归纳四会单词、重点词组、重点句型、语法和课本对话等知识，汇编成讲义发给学生，使学生脑子中有清晰知识体系网络图。第二阶段专项训练复习是对针对名词、冠词、非谓语动词、并列句和复合句等作专项的训练。此阶段的任务主要通过语法线来巩固、深化课本英语知识。第三阶段综合训练板块任务主要是通过专项题型和模拟测试来全面培养学生综合应试能力水平。综合训练也可从英语总复习一开始时就要有计划安排，如一个星期做一套完整的综合试卷或专项题，以便培养整体复习英语的意识。听、说、读、写能力训练板块始终贯穿在整个三个阶段里，要反复有层次地训练，每周要固定时间，保证训练次数和质量，同时做好点拨和评析，传授各种方法和技巧，使知识和能力形成互补，提高复习效率。
三、分层指导，在统一练习同时重视分层的作业布置
英语总复习阶段学生的英语水平已经参差不齐，根据知识掌握程度和学习品质可以分成优秀生，中等生和后进生，其中后进生的英语水平还不如七年级学生的英语水平。那么教师既不能放弃某些学生，也不能一个层次要求所有的学生。只有根据学生个体的学情分层指导和要求才为上策。首先英语语言知识点分层要求可从教材自身出发，对于每个单元，细到梳理知识点，在此基础上进行“淘金”活动，将知识点梳理成金字塔形，将不同的知识点对应于不同层次的学生，分层次分解知识点，对相应层次的学生提出相应的需求。其次要引进竞争机制来分层次优化，根据每位学生的能力，制订标准分，进行奖励，使他们个个有对手，人人有复习目标，人人有危机感，把学习积极性最大限度地调动起来。最后对于后进生特别要多进行情感关怀，根据学生不同情况帮助他们找出名自的薄弱环节，采取人盯人办法，一方面进行面对面辅导；另一方面认真面批他们的练习和试卷，分析他们的错误原因，帮助他们写出正确答案。这样每个层次的学生都相应到达应有的复习水平，提高了复习效率。
【1】ZeigerM.Essentialsofwritingbiomedicalresearchpapers.NewYork：McGraw-Hill，Inc，1991.257-283
【2】LawrenceJ.Appel，etc.ComparativeEffectivenessofWeight-LossInterventionsinClinicalPractice[J].NewEnglandJournalofMedicine， 2011，365：1959-1968
【3】陈攻，李晶.医护人员习得医学英语专业词汇方法浅析[J].护理学杂志，2008，23（1）：16-19
【4】何筑丽，国林祥.医学英语写作与翻译[M].北京：高等教育出版社，2000
【5】任如意.医学论文英语写作的文体特点[J].实用儿科临床杂志，2009，24（17）：1383-1384
参考文献：
[1]Blackmore，Susan.TheMemeMachin[M].NewYork：OxfordUniversityPress，1999.
[2]Dawkins，Richard.TheSelfishGene[M].NewYork：OxfordUniversityPress，1976.
[3]陈琳霞.模因论与大学英语写作教学[J].外语学刊，2008（1）：88—91.
[4]何自然.语言中的模因[J].语言科学，2005（6）：54—64.
[5]张颖、模因论对大学英语听说教学的启示[J].西安外国语大学学报，2009（3）：111—113.
参考文献：
［1］Knoy，Ted，AnEditingWorkbookforChineseTechnicalWriters［M］.Hsinchu，Taiwan：CWebTechnology，2000.
［2］琼·平卡姆（美）.中式英语之鉴［M］.外语教学与研究出版社，1998.
2.利用英语歌曲学习祈使句
祈使句是日常生活中用得最多、最口语化的句型。可利用的这类歌曲很多，如Let’sgonow,Lookatmydoll,Let’ssinganddance,Ifyou’rehappy等等。这些歌曲的风格大多节奏明快、轻松活泼、动作感强，最适合小学生，也最受他们的欢迎。教师在教唱的过程中，辅之相应的动作和丰富的表情，课堂上的气氛顿时活跃起来。学唱这类歌曲的方法很多，如独唱、合唱、分小组唱、男女对唱等，形式多样。
3.利用英语歌曲帮助日常交流
这类歌曲很多，覆盖面最广，常常涉及到五个“W”—who/what/where/when/why和一个“h”---how，如What’syourname?Howoldareyou?WhereisMickeyMouse?等。这类歌曲与课本内容联系很密切，往往就是一节课的主要内容。但是，这些歌曲的歌词也相对比较复杂，比较适合语音、语调和语感较好的中、高年级学生。
4．利用英语歌曲学习表达思想
在歌曲教学中，教师丰富的表情、生动的语言和多彩的道具，构成了一场场出色的歌舞剧。教师是出色的编导，而可爱的学生就成了出色的演员。
中图分类号：H315 文献标识码：A
文章的主体是科技论文的核心部分，是主题思想的展开和论述。作者可根据需要在文章中加小标题，将主体内容分为几个部分进行论述。科技论文的英文写作通常把每段的主体句（Topic Sentence）放在段落的第一句，全段围绕主体句论述，定义与叙述是科技论文写作中又一种常用的写作方法。
一、定义（Definition）
（一）Introduction
When making a hypothesis（假说）or other statement， scientists must make sure that they will beunderstood by other researchers. Misunderstandings occur when there are different concepts of what is being discussed.
A definition answers the question， “What is it?” Sometimes a definition is necessary because a word or concept has more than one meaning. For example， whether carbon is a metal or nonmetal depends on how you define carbon. At other times， a definition is required because a term is being used in a special way. For example， physicists use the terms work and energy in ways that are more specific than their common meanings. A definition should be complete enough to include all the items in the category yet narrow enough to eliminate items that do not belong. The Greek philosopher Plato once defined man as a two-legged creature that has no feathers. The problem with Plato's definition was that it did not distinguish a man from other two-legged creatures without feathers. Communication between researchers is dependent on precise definitions of substances， concepts， processes， and ideas.
Greek philosopher Plato 希腊哲学家帕拉图
（二）Sentence patterns
Sentence pattern 1:
An astronomer is a scientist whostudies the universe.
A barometeris an instrumentthat measures air pressure.
Conductionis a process by which heat is transferred.
A laboratoryis a place whereexperiments are performed.
Physicsis the study ofmatter and energy.
A volt is a unitfor measuring electrical pressure.
Sentence pattern 2:
Mercuryisa liquidmetal.
Asbestosis a fire-resistantmineral.
A dinosaurisa prehistoric reptile.
A monkeyis a small， long -tailedprimate.
（三）Application Examples
be 是
mean 意思是，意味着，意指
denote 表示，指
imply 意思是，意味着
be named 命名为，被称为
Examples：
1. Printers are output devices.
打印机是输出设备。
2. Multiprogramming means the existence of many programs in different parts of main memory at the same time.
多道程序意味着在主存储器的不同部分同时存在着多个程序。
3. Data denotes a collection of facts that can serve as operands to computer program.
数据是指可作为计算机程序操作对象的集合。
4. A “system” implies a good mixture of integrated parts working together to form useful whole.
“系统”意指将协同工作各部分适当地综合而成的一个有效的整体。
5. The first digital computer built in 1946 at the University of Pennsylvania was named ENIAC.
第一台计算机是1946年在宾夕法尼亚大学建造的，命名为ENIAC。
二、叙述（Describing）
（一）Introduction
A description serves to introduce a scientist's view of the world. It may describe conditions， results of an experiment， chemical changes， physical movements， or what is seen through a telescope or microscope. A description may also tell the characteristics or distinctive features of an object―how it look， sounds， tastes， smells， works， or is produced.
The nature of something can be explained by describing it. For example， the concept of an atom is difficult to grasp from a definition alone， but a description of its appearance， detailing its structure and function， makes it easier to visualize.
（二）Sentence patterns
The Nile River is 4，145 miles long.
Mount Everest is 8，848 meters high.
The Dead Sea is 11 miles wide.
The Nile River has a length 4，145 miles.
The Sun has a surface temperature of 11，000°F.
The Grand Canyon has a depth of 5，500 feet.
The color of iodine is purplish black.
The texture of sand is rough and granular.
The orbits of planets are elliptical.
Pluto is relatively small.
Blue stars are extremely hot.
Copper salts are slightly blue in aqueous solutions.
（三）Application Examples
be是
be considered （to be） 被认为是，被看作
be known as 被称为是，被认为是，即
be referred to as 称为，叫做
be thought of as 被认为是
be regarded as 被认为是
Examples:
1.This ability to allow interrupts to interrupt previous interrupts service routines safely are referred to as nested interrupts.
允许某些中断去中断先前的中断服务程序，并能正确运行的能力称为嵌套中断。
2.One of the most important characteristics of a computer is its capability of storing information in its memory long enough to process it.
计算机最重要的特性之一就是具有这样一种能力，即在它的存储器中保存信息时间长到足以对这些信息进行处理。
3.In the majority of applications the computer's capability to store and access large amounts of information plays the dominant part and is considered to be its primary characteristic.
在大部分的应用中，计算机能够存储和访问大量的信息这一特性，起了关键的作用，并被看成是计算机的主要特点。
二、商务英语会话中的语用范畴
语用范畴在商务沟通领域必不可少，如奥斯汀的言语行为理论、格莱斯的合作原则等。这些理论在商务英语会话中的作用不容忽视，对理论的理解和应用在相当大的程度上直接决定着沟通的成败与否。言语行为理论始于西方，并由约翰·兰肖·奥斯汀提出，该理论使得语用学研究进入新领域。奥斯汀的言语行为理论主要包括两个方面：首先，讲述语言单位及其意动功能；其次，谈及了语言单位的主客体视角所导致的行为。例如，当中国商人和中亚国家进行贸易谈判时，中国客户表情如果表现得僵硬或者发出有言外之意的言辞，中亚商家将无法理解，因为在中亚国家里，面部表情所表达出来的意思占据着听话人的主要判断，而这一判断如果失败将直接导致言外之意的无法表达，在这一会话过程中就会出现双方难以理解的问题。
1.语块与语言表达
语块有助于提高语言表达的流利性和准确性。语块是语言使用中形成的习惯性语言构块，使用者无需知道其内部结构就可以流利地表达，在交际时可以整体提取使用。Nattinger&DeCarrico指出，人们使用语言的流利度不取决于学习者大脑中存储了多少生成语法规则，而在于存储了多少语块。另外，语块大都是按照一定的语法规则生成的，交际时学习者不需特意注意语法结构。在商务活动交际过程中，学习者可以直接提取大脑中储存的符合特定语境的语块，灵活运用语块，更顺利地完成商务交际目的。
2.语块与语用能力
语块可以提高交际的得体性。因为每个语块都有语用功能，表示同一功能的语块以语义场(se－manticfield)的形式存在于大脑中，提取使用时根据交际语境、交际对象等具体情况，选取最合适的语块。因此，语块教学可以使学生获得一定交际策略的能力，以保证交际的顺利完成。正如Krashen(1978)指出的，学习者出于交际压力的影响，必须记一些公式化的套语。为了编制出创造性的语言，他们必须记住许多现成的口头话语以弥补第二语言规则的不足。通过掌握大量的语块，增加学习者语言的储备，使语言交流更顺利。商务英语交际时，学生可以根据具体的商务语境、交际对象、交际时的主题等，选取合适的语块来提高交际的得体性。
3.语块与词汇的记忆
语块学习有助于提高学生的词汇记忆与习得。语块有利于词汇的学习。首先，由于语块是较大的词汇构块，甚至是完整的句子，它们就像不可分的“组块”储存在大脑词库中，容易自动检索。另外，语块作为整体在语言中出现的频率较高，可确保语块能自然地、不断地得到循环。语块高频出现和语境依附的特征容易使学习者对学习内容产生“形式-语境-功能”的联系，从而以整体形式习得与储存。语块意义是置于特定的语境，比脱离语境单独背词汇更容易记住，而且不容易遗忘。
二、基于语块的商务英语教学方法
商务英语交际活动的顺利进行很大程度上依赖于商务英语中的语块现象。建立以语块为纽带的教学法是提高学习者商务英语能力的一个切实可行的方法。因此，可采取以下方法实施“语块”教学法。
1.识别语块
教学活动以语块为中心。教师帮助学生了解语块的特点、作用和类型，引导学生识别和区分语块，激活学生的语块意识，在学生潜意识中把语块作为语言学习的最小单位。教学中教师应明确向学生指出不同商务体裁语篇中高频出现的语块，除了要求学生记忆并会使用教材中出现的语块外，还可以结合语块中的核心词汇提供一些常规搭配，供学生反复操练，培养学生对语块的辨别能力和敏感性。同时，教师可使用类比、归纳、同义、反义、形近等方法让学生把新学到的语块和之前学的词汇或语块建立起联系，增强学生对词汇学习的系统性，便于词汇的记忆、储存和提取，以提高学生的商务英语能力。
2.归纳语块
了解了语块的特点和功能后，教师可引导学生根据不同的语块分类标准，将商务活动中不同语境中的语块使用情况进行归纳分类。如商务写作课程中的商务信函写作，教师可引导学生根据不同信函的种类(如询盘和报盘)归纳出其中每个环节的语块使用情况。另外，教师可利用权威地道的商务英语信函例文指导学生进行商务英语信函的写作，强化学生识别商务英语信函中的语块意识，加强基于语块的商务英语信函写作。
