棋牌类网络游戏客户端架构设计

网络游戏已经成为互联网产业的热门。在实际开发棋牌类网络游戏工作的基础上,提出了一款通用的游戏客户端架构设计。该客户端架构的主要功能是实现一个游戏大厅。该架构负责和服务端通信,利用通用的第三方接口运行具体的第三方游戏逻辑实现游戏大厅。在架构设计中,采用了多视图设计、大客户端量的仿真、快速访问树形结点和第三方接口等相关技术。开发结果表明,该架构能够较好满足功能要求。     

Responses to 9/11 reveal opportunities— and barriers—for commercial ADR

The fallout for conflict resolution professionals from the terrorist attacks of Sept. 11, 2001, strikes at the core of their existence: What do they do? What do they provide? Maria R. Volpe and Staci Strobl, of New York, have been looking broadly at the question of “deliverables” since 9/11. They discuss the business ADR aspects of that research, and provide lessons the profession should have learned.     

Satellite locations—1984

In a brief 20 years the number of satellites in the geosynchronous and geostationary orbits have increased by enormous bounds. Far more than Arthur C. Clarke, himself, could have anticipated two decades ago. This paper lists those satellites in geographical order, starting with the longitude of Greenwich and proceeding eastward, and the second table starting at Greenwich and going westward. The potential for additional growth in the number of geosynchronous and geostationary satellites still exists for tomorrow through new technologies being designed today.     

A Case Study of Hardware/Software Partitioning of Traffic Simulation on the Cray XD1

Scientific application kernels mapped to reconfigurable hardware have been reported to have 10times to 100times speedup over equivalent software. These promising results suggest that reconfigurable logic might offer significant speedup on applications in science and engineering. To accurately assess the benefit of hardware acceleration on scientific applications, however, it is necessary to consider the entire application including software components as well as the accelerated kernels. Aspects to be considered include alternative methods of hardware/software partitioning, communications costs, and opportunities for concurrent computation between software and hardware. Analysis of these factors is beyond the scope of current automatic parallelizing compilers. In this paper, a case study is presented in which a simulation of metropolitan road traffic networks is mapped onto a reconfigurable supercomputer, the Cray XD1. Five different methods are presented for mapping the application onto the combined hardware/software system. An approach for approximating the performance of each method is derived through analytic equations. Our results, both analytically and empirically, show that key predictors of performance (which are often not considered in reported speedup of kernel operations) are not necessarily maximum parallelism, but must account for the fraction of the problem that runs on the reconfigurable logic and the amount data flow between software and hardware.     

DECnet/OSI—Part 3: DECnet/OSI Network Management

In the previous articles on DECnet/OSI the focus has been on the technical aspects of Digital's implementation, alias Advantage Networks. The openness of Advantage Networks is both good and bad. It's good because you have the freedom to mix and match network devices to fit your specific needs. It's bad because a heterogeneous network environment will be very difficult to manage. In this article the discussion is on Digital's concept of managing a DECnet/OSI network management.     

Two-carrier conduction in MOS tunnel—Oxides II—Theory

Analytic expressions describing electron and hole current flow in the metal/tunnel—oxide/n-silicon structure are derived. In the particular approach that is taken, the tunneling barrier presented by the SiO₂ layer is treated using a “thick-oxide” MOS model; i.e. a trapezoidal tunneling barrier is used. Rather than assume a constant tunneling probability, the dependence of the tunneling barrier on applied bias and on the minority carrier density at the semiconductor surface is also included. Calculations based on the resultant equations are found to be in good agreement with experimental observations, and to correctly predict the “current-multiplication” effect that occurs under conditions of minority carrier injection to the Si---SiO₂ interface [1].

The derived equations are used to simulate device behaviour under various experimental conditions, including the effects of minority carrier injection, non-zero flatband voltage, and changes in substrate doping concentration and temperature. In addition, device parameters such as barrier height and carrier effective mass are also investigated with regard to their effect on the resultant electron and hole tunneling currents.     

In-orbit demonstration of optical IOL/ISL—the silex project

The use of optical communications for the high-data-rate links of the future European Data Relay System (EDRS) is receiving much attention. To confirm the feasibility of such communications links, an experimental system (SILEX) consisting of three satellites (two in geostationary orbit and one in low earth orbit) is planned for 1992 or 1993 to demonstrate both inter-orbit link (IOL) and intersatellite link (ISL) capabilities. A detailed feasibility study was performed from January to July 1987 under a European Space Agency (ESA) contract with Matra (France) as prime contractor, ANT (West Germany), Telespazio and Selenia Spazio (Italy) as subcontractors, and contributions from Berlin (France) and Dornier (West Germany). The system is based on GaAlAs semiconductor technology (0.8 μm) with silicon avalanche photodiodes (APDs) as detectors and arrays of charge-coupled devices (CCDs) for both acquisition and tracking sensors. The design will allow wavelength division multiplexing (WDM) and high-data-rate transmission to be demonstrated. The expected data rates are 120 Mb/s duplex for ISL, 1 Mb/s on the IOL forward link (GEO→LEO) and two to four simultaneous 60 or 120 Mb/s channels on the IOL return link (LEO→GEO).     

Vectus—Intelligent Transport

Personal Rapid Transit (PRT) is a transportation concept with small vehicles on a low weight structure, that combines many of the best aspects of today's urban public transport, and packages them together with unparalleled service and lower total cost of ownership. Vectus, with operations in Korea and Sweden, is at the forefront of PRT technology. Vectus has built a PRT test track in Sweden for validation of the system, and for obtaining safety approval. For the test track, in-track linear motors are used powered by standard industry inverters combined with an in-house control concept. The system and its operational experiences are described.      

Network services—outsourcing

Network outsourcing is an alternative which through advanced technologies, standardization and a close partnership between the client corporation and provider, facilitates an effective and economical means of meeting present and future needs of various corporate user communities. Solutions typically consist of a wide array of services ranging from full operation of the network which includes assumption of assets and personnel to responsibility for various segments of the network such as Help Desk or Vendor Liaison functions.     

APPN—An Introduction

This first article in a series on managing APPN Networks briefly introduces a relatively new networking architecture. Both traditional hierarchical SNA Networks and modern distributed Client/Server environments highly benefit from utilizing APPN functionality in their network configurations. APPN actually grew up in an environment which combines these two worlds: The IBM midrange computer environment based on AS/400 machines. APPN is part of IBM SNA (Systems Network Architecture) and many abbreviations in this series of articles actually are commonly used SNA terms.     

APPN—Communications Scenarios

In this second article in the series on managing APPN networks we will go through several APPN communications scenarios and analyse how the APPN protocol works when resources are found, routes are selected and communications sessions are established and maintained.     

Finding the Tuning Curve of a CMOS—LC VCO

A nonlinear perturbation model of a complementary LC-tuned voltage-controlled oscillator is derived, which consists of two mutually-coupled second-order differential equations. The first-order approximate periodic solution of the describing equations is found, obtaining closed-form expressions for both the amplitude and the harmonics of oscillation, as well as for the correction of the oscillation frequency due to the nonlinear effect of varactors. This allows us to find the tuning curve in explicit form. The accuracy of presented formulas was validated by circuit simulations.      

Cortical Models Onto CMOL and CMOS— Architectures and Performance/Price

Here we introduce a highly simplified model of the neocortex based on spiking neurons, and then investigate various mappings of this model to the CMOL CrossNet nanogrid nanoarchitecture. The performance/price is estimated for several architectural configurations both with and without nanoscale circuits. In this analysis we explore the time multiplexing of computational hardware for a pulse-based variation of the model. Our analysis demonstrates that the mixed-signal CMOL implementation has the best performance/price in both nonspiking and spiking neural models. However, these circuits also have serious power density issues when interfacing the nanowire crossbars to analog CMOS circuits. Although the results presented here are based on biologically based computation, the use of pulse-based data representation for nanoscale circuits has much potential as a general architectural technique for a range of nanocircuit implementation.     

Getting the best possible deal by helping—not pleasing—the neutral

There's more that parties can do to help themselves in mediation. Veteran Evanston, Ill., neutral Stephen B. Goldberg describes how parties can work more effectively with the neutrals they hire to help them close cases and deals     

Dual H∞ Algorithms for Signal Processing— Application to Speech Enhancement

This paper deals with the joint signal and parameter estimation for linear state-space models. An efficient solution to this problem can be obtained by using a recursive instrumental variable technique based on two dual Kalman filters. In that case, the driving process and the observation noise in the state-space representation for each filter must be white with known variances. These conditions, however, are too strong to be always satisfied in real cases. To relax them, we propose a new approach based on two dual H_infin filters. Once a new observation of the disturbed signal is available, the first H_infin algorithm uses the latest estimated parameters to estimate the signal, while the second H_infin algorithm uses the estimated signal to update the parameters. In addition, as the H_infin filter behavior depends on the choice of various weights, we present a way to recursively tune them. This approach is then studied in the following cases: (1) consistent estimation of the AR parameters from noisy observations and (2) speech enhancement, where no a priori model of the additive noise is required for the proposed approach. In each case, a comparative study with existing methods is carried out to analyze the relevance of our solution.     

Development of Optical MUX/DEMUX on Silicon Optical Bench—Assembly Accuracies

An optical subassembly of MUX/DEMUX where optical devices are hybrid-integrated on a silicon optical bench (SiOB) using a passive alignment method is reported. A tight tolerance of positional and tilting angular accuracy is required for optical devices attachment in order to maximize the coupling efficiency. The critical positioning transverse to the optical axis merely depends on the symmetry, and accuracy of the position and shape of trenches. Any inaccuracy primarily affects the noncritical positioning, i.e., $z$-axis and $theta{ z}$, in the direction along the optical axis; misalignment accumulated and causes undesired insertion loss. All the piece parts, i.e., mirror, thin-film filters (TFFs), ball lens, SiOB, etc., have a defined tolerance in their dimensions and surfaces which increases the challenge in achieving high placement accuracy along the optical axis. The effects from these inherent inaccuracies of the position and shape of trenches and piece parts could be minimized by optimizing the adhesive volume, improve the bottom flatness, proper procedure selection. Misalignment at each axis, e.g., x-, y-, z-, $theta{ x}$, $theta{ y}$, and $theta{ z}$ was characterized and its effect to the coupling efficiency was discussed.