A VLSI CMOS delay oriented waveform converter for polyphasefrequency synthesizer

In this paper, we present a waveform converter implemented on a 0.25-μm CMOS technology using a dedicated design methodology (Delay Oriented Design). The circuit converts a square wave signal in both in-phase and quadrature-phase sinusoidal differential outputs. It also multiplies the frequency by seven. The output frequency range of this converter extends from 1.05 GHz up to 2.17 GHz. This converter is dedicated for the design of a third-generation mobile phone synthesizer using a double-loop architecture. For an output frequency of 2 GHz, the measured phase noise at 10-kHz offset from the carrier is -97 dBc/Hz. The circuit consumes 50 mW from a 2.5-V supply     

压水堆核燃料循环的经济分析程序介绍

所开发的压水堆核燃料循环分析计算机经济程序包括12个子程序,代表着压水堆整个核燃料循环各种不同的工艺过程。本程序能算出压水堆核电站核燃料循环中燃料费用对发电成本的影响,给出各工艺过程对燃料成本的敏感度分析,并尽可能给出燃料循环中燃料材料及服务的价格数据.     

Modelling thermal degradation of composite materials

A one–dimensional, transient thermal degradation heat transfer model for the response of composite materials when exposed to fire is presented. The model can handle layers of different materials. Material properties are functions of temperature. The reaction can be specified using Arrhenius‐type parameters or by inputting a density–temperature relationship determined by any experimental technique such as thermogravimetric analysis. The model is validated against the experimental data presented in Boyer's 1984 dissertation. Overall, the model provides excellent agreement with the experimental data. It is shown that very little difference is found between results arrived at by Arrhenius kinetics and results obtained by specifying the easier to measure density–temperature relationship. From this it is concluded that this technique is a viable alternative to Arrhenius‐type models. Copyright © 2006 John Wiley & Sons, Ltd.     

Effect of the Treatment Temperature on the Surface Drying Set of Sugi Boxed-Heart Square Timber

High-temperature and controlled humidity treatment before drying has proven to be highly effective in preventing surface checks by forming drying sets in the surface layer of boxed-heart square timber in Japan. In this study, we examined the differences of the surface drying sets on sugi timber under different treatment temperatures. As a result, the width of a surface check after drying was much smaller at a treatment temperature of 120°C than at 80°C, and this indicates that the drying set with 120°C treatment would be larger than that with 80°C treatment. Also we observed that treatment temperature had a greater effect on the drying set as the drying advanced.     

High-temperature sensible-heat storage options

Alkali-metal carbonate salts meet the requirements for high-temperature solar central receiver systems, but because of their corrosiveness they present special problems in the design of storage tanks. In order to reduce corrosion and temperature sufficiently to retain strength in the storage containing wall, internal and thermal insulation is required. We present design options and operation criteria for sensible-heat, molten-salt storage with internal insulation.     

Exploiting ILP, TLP, and DLP with the polymorphous trips architecture

The Tera-op reliable intelligently adaptive processing system (TRIPS) architecture seeks to deliver system-level configurability to applications and runtime systems. It does so by employing the concept of polymorphism, which permits the runtime system to configure the hardware execution resources to match the mode of execution and demands of the compiler and application.     

Mechanism of resistance microwelding of crossed fine nickel wires

Resistance microwelding of fine crossed nickel wires is of increasing industrial importance for electrical connections in downsized electronic and medical devices, but the understanding of the process is very limited. A study has, therefore, been performed to clarify the basic joining mechanisms, in which the effects of main process parameters (welding current and force and weld time) were investigated by detailed mechanical testing and metallurgical examinations. A bonding mechanism with main process stages (wire cold collapse, surface melting, molten-phase squeeze-out and, solid-state bonding) was proposed. A new technique has also been developed to optimize the process by initiating the welding current well before the electrode force has reached its full nominal value.     

Single-Threaded vs. Multithreaded: Where Should We Focus?

Today, with the increasing popularity of multicore processors, one approach to optimizing the processor's performance is to reduce the execution times of individual applications running on each core by designing and implementing more powerful cores. Another approach, which is the polar opposite of the first, optimizes the processor's performance by running a larger number of applications on a correspondingly larger number of cores, albeit simpler ones. The difference between these two approaches is that the former focuses on reducing the latency of individual applications or threads (it optimizes the processor's single-threaded performance), whereas the latter focuses on reducing the latency of the applications' threads taken as a group (it optimizes the processor's multithreaded performance). The panel, from the 2007 Workshop on Computer Architecture Research Directions, discusses the relevant issues.