A Study of the Effects of the Current InternationalSettlement of Internet

1　TheUnbalancedDevelopmentofInternetandtheDigitalDivideAmongCountries　　Withtheadvanceofinformationtechnology ,Internethaspenetratedintovariousaspectsofsocialandeconomiclifedeeplyandimprovedthedevelop mentofproductivityenormously ,which producestheobvioustendencyofeconomicglobalization .In ternetexpeditestheprocessofeconomicglobaliza tion ,throughwhichanycountrywouldbeabletoparticipateintheglobalproductionandrebuildingthetraditionalindustrymoreintensivelyandexten sively.Alotofnewinformati…     

The Application of the Theory of the Price Elasticity of Demand to the EMS Management

1　Introduction　ExpressMailService (EMS )wasopenedupbyChinaPostintheearly 80stomeettheneedsofeco nomicdevelopment.It sthemostcompetitiveoneofthepostservices.There recivilaviation ,Chinarail wayandotherprivateexpressdeliverycompaniesdomesticallyandUPS ,TNT ,DHLandTEDEXcompetingwithEMSintheinternationalmarket.OneofthemostpowerfulcompeteweaponofthesecompaniesisthelowerpricethanEMS[1 ] .BecauseofthefiercecompetitionEMSdeclinedfromthemo nopolistindomesticandinternationalmarketoftheear…     

Influence of parameters of the semiconductor–dielectric interface on the current of the guard ring of silicon photodiodes

Relationships, which determine requirements for the resistance of the inversion layer for decreasing the influence of the guard ring on the dark current and photodiode noisess and allow obtaining the specified intercoupling coefficient between photosensitive elements in multielement photodiodes, are given. It is shown that dependences of the current of the guard ring on the bias voltage and the charge on the Si–SiO₂ interface in the presence of the inversion layer satisfy the current generation model in the space-charge region of the current. The resistance of the inversion layer increase with an increase in the bias voltage in accordance with the relationship R_u ～ V^1.5.     

Design of the Test System for the Dynamic Function of the SLC PCB

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Selection of Parameters of the Primary Feed of the Luneberg Lens for the Sum–Difference Operating Mode

Excitation of the Luneberg lens by an arc antenna array of open-ended rectangular waveguides forming the H₁₀ wave is studied. Technical limitations imposed on the array of primary feeds in order to form the sum and difference operating modes of the antenna system are discussed.     

Implementation of the Broad-band User Access Network and the Study of the Key Algorithm for Improving the Performance of Asymmetrical Networks

Implementation of the Broad-band User Access Network and the Study of the Key Algorithm for Improving the Performance of Asymmetrical Networks     

III-Vs — the tip of the spear

GaAs and related compound semiconductors have military origins and the past decade has seen devices based on them being successfully battle-tested. Radar systems are the leading application for these materials, while other important areas include secure military radios, global positioning system (GPS) navigation, night-vision and other enhancements to the battlefield and naval warfare. All of these applications rely on the improvement in sensing and detection that III-V-based devices can confer. This article looks at some of the most interesting defence uses of compound semiconductors, such as phased array radars and missiles.     

Application of Spatial Filtering Techniques in the Measurement of the Velocity

As one of the interesting optical techniques for measurements of the velocity,the spatial filtering method is treated briefly in this paper.We shown theoretical analysis and calculation of spatial filtering velocimetry,and discussed two-dimensional measuremints of the velocity.About the data processing,we used A/D conversion and interfaced with a microcomputer,so that the data can be processed automatically by the microcomputer .The preliminary experiment was performed and the experimental results show the usefulness of the present method for measurements of the velocity.     

A Study of the Development of the World Postal Parcel Service

Inrecentyears,themarketproportionofthepostalparcelservicehastakenonadescendingtrendallovertheworld .Meanwhilethemarketcompeti tionhasbecomesharperandsharper.ManyPostsintheworldareenergeticallyexploitingthemarkettoadvancetheirpostalparcelserviceandseekingforcollaborationtostrengthentheirmanagementofthepostalparcelservice.1　TheAnalysisontheMarketofPostalParcelService　　Accordingtothedocumentsinthe“ThePlanfortheDevelopmentofPostalParcelService 2 0 0 1～2 0 0 4”supportedbytheUPUPostalPa…     

The Influence of the Crystal Structure of the GaSb–InAs Matrix on the Formation of InSb Quantum Dots

Semiconductors - Uniform arrays of the InSb quantum dots with a surface density of nQD = 2 × 109 cm–2 were obtained by liquid phase epitaxy on a matrix layer based on a multicomponent...     

Analysis of Postal Development of the World

What will the Post in the world be like in 2005? At first glance, in view of worldwide structural changes, market liberalization and technological development, this question seems very hard to answer. However,without being able to draw a precise picture of the future post services, it can be affirmed that all current providers of postal services will have to face a very different environment from the current one. The objective of this analysis is to contribute to the future development by examining at the worldwide and regional level the major variables influencing the postal industry' s core businesssector, the letter-post, through analyzing the data published by the Universal Postal Union.     

Application of the Appraisal Activities of the Products,Techniques and Applications Projects of BIRTV

Name of the ItemChinese‘EnglishTyPe of APPlieation口Audio Produetion and Broadeast口Video Produetion and Broadeast口Radio and Television Transmission and Delivery口Information Engineering口Film production,Projeetion and Distribution.The ProPertiesof the Item口Produets TyPe口Technieal TyPe口APplieation TypeProduetioll Unit of theItem DeveloPerReeonlnlexldation Unit ofthe Item APPlieaitonLiasion PersonnelTel.E一mailZIP CodeAdd.Of the APPlyingUnitOther necessary materials…     

A Study of the Characteristics of Consumers'''' Behavior under the Web Environmen

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To the understanding of the formation of the III–V based droplet epitxial nanorings

The paper deals with the kinetics of the droplet epitaxial GaAs quantum ring formation grown on AlGaAs (0 0 1) surface. The observation is, that the aspect ratio of these nano structures is depends not only on the technological parameters but on the size of the initial droplet. Under appropriate growth conditions, the depressions, in the middle of the rings are deeper than the surface level of the substrate. A large number of tests show, that the depressions in the middle of the small rings are often deeper than that of the larger ones. The number is larger, than just statistical fluctuation. An explanation for this phenomenon and its kinetics are given in the paper, based on the size dependence of the material properties, like for instance solubility. The plausible explanation assumes is that the probability of the crystal seed formation in the larger droplets is higher.     

Assessment on IT-based Technical Innovation of the Subordinate Company of the Corporation

Information technology （IT） is one of the most important means by which companies can win an advantaged position in drastically competed market. It has a positive effect on the advancement of the corporation＇s technical innovation. The application of IT can promote the communication among subordinates of a corporation or group, reduce explicit boundaries of the subordinates, and boost the ripple effect of technical innovation of the subordinates. Not only does any subordinate company within a corporation need to assess both technical and economic benefits brought to the corporation itself by technical innovation, but also it should thoroughly analyze how the ripple effect of technical innovation among subordinate companies plays a significant role in the boosting value of the corporation as a whole. In this paper, a scientific approach to assessing technical innovation of a subordinate company is proposed through analyzing the ripple effect of IT-based technical innovation on subordinate companies.     

Implementation of the Broad band User AccessNetwork and the Study of the Key Algorithm for Improving the Performance of Asymmetrical Networks

This thesis is based on the design and development of ADSL access networks. We h ave completed the hardware and software functions in two main ADSL equipments: A TU C and ATU R. With the system design, we carry out researches to find out ef fective methods to improved performance in the following aspects: (a) how to all ocate limited bandwith among services with different QoS requirements and (b) what is the effect of asymmetric links on TCP end to end flow control mech anism. We make detailed analyses and propose useful solutions to those problems we find. The main contents of this thesis are as follows: (1) the design and rea l ization of ADSL access system. This part includes the principles of ADSL access technology, ADSL broadband access network architecture, and ATM over ADSL protoc ol models that we use in our system. We give detailed hardware and software desi gn steps in this part, and list system testing results to show the system perfor mance. In our hardware, the CPU is a RISC microprocessor. Combined with a high speed digital signal processor, the whole system can hold high reliability. Our software design platform is a Psos multi task real time operation system. We h ave developed a series of hardware drivers besides other tasks for high level co ntrol and interruption processing. Currently, our system has reached the expecte d performance under test environment. Our next step is the development of DSLAM and in this part we give a feasible design scheme. (2) Packet scheduling policy I n ADSL system. In order to optimize ATU R performance, we need a scheduling pol icy to regulate the order and number of packet output to the uplink. For this pu rpose, we study the scheduling algorithm design methods in a single network node and their performance. After studying the existing algorithms carefully, we fir st conclude certain important design principles and criterions for scheduling po licy evaluation. And then by using service curve function, we make detailed perf ormance analysis of a typical scheduling policy — the earliest deadline first. The advantage of characterizing service by using a function is that the service curve can provide a wide spectrum of service characterization. With this method, we first develop a generalized algorithm for calculating the deadlines used in the service curve based on the earliest deadline first policy, and then design a simplified computing program for an important curve. After that, holding fair b andwidth allocation and packet deadline guarantee as policy evaluation standards , we analyze this scheduling policy performance and propose solutions to those p roblems that we find. Finally, we, in theory, prove these improving algorithms. All these solutions and algorithms we design in this part are now under developm ent in real systems and will enhance system performance. (3) Effects of asymmetr I c links on TCP performance and solutions. TCP is a widely used transmission cont rol protocol. It regulates its forward data sending through reverse ACKs. What a re the new problems to its flow control mechanism on asymmetric links and how to solve them are the two main points of this part. We first study the relationshi p between normalized bandwidth ratio, link buffer capacity and TCP link throughp ut under asymmetric link models. We find that TCP ack transportation on slow bac kward link is a key reason that causes the problems in TCP asymmetric links. Ser ving this as a start point, we present several improving solutions to TCP flow c ontrol algorithm and test them through simulation. Besides, TCP has been widely implemented in many networks. To give compatibility with current TCP end users, we use scheduling solutions to regulate data packet and ack packet transmission ratio onto uplinks. In the theoretical analysis of several typical scheduling po licies, we find a feasible algorithm to control TCP data efficiency on asymmetri c links. Finally, we prove those analyses and propose algorithm through simulati on.     

Influence of the abnormal ratio of the dependence of cathode sputtering rate on the current in a glow discharge†

An experimental investigation of the dependence of cathode sputtering rate W on discharge current I has been carried out in n wide range of changes of abnormal ratio l\l_n (in the different measurements I/I_n = l-6-37), where I_n is the current at which the discharge passes from normal to abnormal conditions. The measurements have been made with three experimental devices with iron cathodes and the gas filling a Penning mixture 99% Ne + 1% Ar. The pressure p in the devices was changed in the interval of p = 3—25.5 Torr, It is shown that in such a, wide range of changes I/I_n the dependence W(I) is no longer a power function. However, for convenient practical use of this dependence and for comparison with results of previous investigations, a good approach for this is the division of the range of changes of current I into two regions. In each of these regions the dependence W (I) may be well approximated by a power function W ～ I^m but with different values of power index m for both regions. A good agreement between the calculated and the experimental values of m for both regions of approximation is obtained. An explanation of the reasons which cause the change of m, when I/I_n is changed, has been proposed.     

Effect on the Propagation Characteristics of the Electromagnetic Waves by the Second-order Radiation of the Moving High-speed Train＊

The effect on the propagation characteris- tics of the electromagnetic waves by the second-order ra- diation of the moving high-speed train is analyzed in this paper. Two Lorentz transformations, one from the sta- tionary reference coordinate system to the moving system and the other vice versa, are employed to derive the the- oretical model for analysis of the propagation characteris- tics of the vertical polarized plane time-harmonic waves, which is oblique incidence to the train. The calculation re- suits show that for the transmitting wave reflected by the moving high-speed train, two main signals can be received. One is at the transmitting frequency and the other is at the second-order radiated frequency. The frequency spectrum between these two frequencies are much larger than which is introduced by the Doppler shift. The frequency and the reflection angle of the reflected wave are no longer equal to the frequency and the incident angle of the incident wave. The changed reflection frequency and angle are related to the train＇s velocity, the incident angle and the azimuth an- gle of the incident wave. The frequency shift is mainly decided by the y-component of the train＇s velocity. It has nothing to do with y-component of the train＇s velocity. The reflection angles will be smaller than the related incident angles when the train goes along --y direction. The reflec- tion angles will be larger than the related incident angles when the train goes along ＋y direction. The reflection an- gle will become larger and larger with the increase of the incident angle and the y-component of the train＇s velocity. The induced current density and the charge density on the surface of the train are increased with the train＇s velocity, and the induced charge is much smaller than the induced current.     

Study on the Complexity of the Bullwhip Effect

Recent years have witnessed a rapid growth of interest in the study of the dynamic behavior of replenishment rules of bullwhip effect. We prove that bullwhip effect and butterfly effect share a same the self-oscillation amplifying mechanism that is the ordering decisions the supplier self-oscillation amplify the perturbations brought by the errors in the processing of retailers' demand information. This results as an explicit self-similar structure of the sensitivity of the system to the initial values duty to the nonlinear mechanism. In this paper, the causes process of the bullwhip effect is described as the internal nonlinear mechanism and study on the complexity of bullwhip effect for order-up-to policy under demand signal processing. The methodology is based on fractal and chaotic theory and allows important insights to be gained about the complexity behavior of bullwhip effect.     

Defects of the structure of semiconductor superlattices grown on the basis of II–VI alloys

The specific features of defects of crystal lattices in multilayer device structures containing small-period (T ? 20 nm) superlattices of type I ZnSe/Cd _x Zn_{1 ? x} Se/ZnSe/.../ZnSe/(001)GaAs and type II ZnS/ZnSe_{1 ? x} S _x /ZnS/.../ZnS/(001)GaAs are studied by the methods of X-ray diffractometry and diffraction rocking pseudocurves, and partially by the X-ray topography. According to the data of quantitative analysis of the X-ray diffraction spectra, the periods of superlattices are in the range T _I = 11.3–16.1 nm (for the compositions Cd _x Zn_{1 ? x} Se with x ₁ = 0.047 and x ₂ = 0.107) for type I superlattices and T _II = 15.6–17.2 nm for type II superlattices (for the compositions ZnSe_{1 ? x} S _x with x ₁ = 0.20 and x ₂ = 0.10). The widths of diffraction peaks from both the ZnSe layers and small-period superlattices in the diffraction rocking pseudocurves considerably exceed their widths in the X-ray diffraction spectra. This fact proves that a pronounced plastic strain with the formation of series of rectilinear dislocations in the crossing slip systems took place in the studied device structures. In order to exclude the generation of dislocations in the growth processes, it is necessary to decrease the concentration of the solid solution to the values x < 0.047 for the first type of superlattices and to the values x ? 0.062 for the second type of superlattices, and to decrease the thickness of the ZnSe and ZnS layers.