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排序方式: 共有347条查询结果,搜索用时 0 毫秒
1.
随着PC平台架构的转变,在2005年到2006年间出现了若干新技术,对PC平台的架构变革产生了深远的影响。随着这些技术被广泛地应用,用户在选购电脑产品时,了解一下这些新技术,显得尤其重要。为此,《电脑迷》杂志搜集了2006年上半年的一些技术关键字进行分析,希望对广大用户的选购有所帮助。 相似文献
2.
Combustion tests of pre-mixture of methane and air in constant volume combustion chamber(CVCC) have been carried out by means of flame propagation photo and gas pressure measurement,the effects of CVCC body temperature,intake pressure of pre-mixture of methane and air,equivalence ratio and location of the built-in adaptor have been investigated.The whole combustion chamber can be divided into two parts,i.e.the upper combustion chamber and the lower combustion chamber,by the built-in adaptor with through hol... 相似文献
3.
Interoperability is the ability of systems to provide services to and accept services from other systems, and to use the services exchanged so as to operate together in a more effective manner. The fact that interoperability can be improved means that the metrics for measuring interoperability can be defined. For the purpose of measuring the interoperability between systems, an interoperability assessment model is required. This paper deals with the existing interoperability assessment models. A compara- tive analysis among these models is provided to evaluate the similarities and differences in their philosophy and implementation. The analysis yields a set of recommendations for any party that is open to the idea of creating or improving an interoperability assessment model. 相似文献
4.
Compensation of hysteresis in piezoelectric actuator with iterative learning control 总被引:2,自引:2,他引:0
This paper presents the application of iterative learning control (ILC) to compensate hysteresis in a piezoelectric actuator. The proposed controller is a hybrid of proportional-integral-differential (PID) control, whose main function is for trajectory tracking, and a chatter-based ILC, whose main function is for hysteresis compensation. Stability analysis of the proposed ILC is presented, with the PID included in the dynamic of the piezoelectric actuator. The performance of the proposed controller is analysed through simulation and verified with experiment with a piezoelectric actuator. 相似文献
5.
王洪梅 KIM Jae-hyung LEE Sang-hyuk KIM Hyung-jung KIM Jin-up KOH Jong-seog 《中南工业大学学报(英文版)》2012,19(2):408-416
The problem of designing a digital frontend (DFE) was considered which can dynamically access or sense dual bands in any radio
frequency (RF) regions without requiring hardware changes. In particular, second-order bandpass sampling (BPS) as a technique
that enables to realize the multiband reception function was discussed. In a second-order BPS system, digital reconstruction
filters were utilized to eliminate the interferences generated while down converting arbitrarily positioned RF-band signals
by using the direct digitization method. However, the inaccuracy in the phase shift or the amplitude mismatch between the
two sample streams may cause insufficient rejection of interference. Practical problems were studied, such as performance
degradation in signal-to-interference ratio (SIR) and compensation methods to overcome them. In order to demonstrate the second-order
BPS as a flexible DFE suitable for software-defined radio (SDR) or cognitive radio (CR), a DFE testbed with a reconfigurable
structure was implemented. Moreover, with a view to further demonstrate the proposed compensation algorithms, experimental
results show that dual bands are received simultaneously. 相似文献
6.
The direct current-direct current (DC-DC) converter is designed for 1 T static random access memory (SRAM) used in display
driver integrated circuits (ICs), which consists of positive word-line voltage (V
PWL), negative word-line voltage (V
NWL) and half-V
DD voltage (V
HDD) generator. To generate a process voltage temperature (PVT)-insensitive V
PWL and V
NWL, a set of circuits were proposed to generate reference voltages using bandgap reference current generators for respective
voltage level detectors. Also, a V
PWL regulator and a V
NWL charge pump were proposed for a small-area and low-power design. The proposed V
PWL regulator can provide a large driving current with a small area since it regulates an input voltage (VCI) from 2.5 to 3.3
V. The V
NWL charge pump can be implemented as a high-efficiency circuit with a small area and low power since it can transfer pumped
charges to V
NWL node entirely. The DC-DC converter for 1 T SRAM were designed with 0.11 μm mixed signal process and operated well with satisfactory
measurement results. 相似文献
7.
8.
Thermal-environment characteristics and comfort of combined radiant-floor (Korean heating system ondol) and convective cooling system 总被引:2,自引:0,他引:2
The thermal-environment characteristics of the existing forced-convection cooling system were compared with those of the convective cooling system, which combined the radiant-floor cooling system using floor-heating panel typically applied to apartments in South Korea with the forced-convection cooling system using improved fan coil unit. The subjective warm/cool-feeling responses to the combined radiant-floor and convective cooling system in the questionnaire survey conducted among the test subjects were analyzed to establish the basic data for the combined cooling system. The results show that in the thermal-equilibrium condition, the vertical air temperature difference in the model living room is larger in the forced-convection-cooling condition. Most of the subjects feel a proper warm/cool feeling on their entire body, but they feel colder on the foot and lower body in the combined-cooling condition. 相似文献
9.
This paper presents a class of non-model2based position controllers for a kind of flexible spacecraft. With the controllers, one can achieve not only the closed-loop stability of the original distributed parameter system, but also the asymptotic stability of the truncated system, which is obtained through representing the deflection of the appendage by an arbitrary finite number of flexible modes. The system dynamics are not explicitly involved in the controller design and stability proof. Instead, only a very basic system energy rehtionship of the flexible spacecraft is utilized. The controllers possess several remarkable advantages over the traditional model-based ones. Numerical simulations are carried out on a kind of spacecraft with one flexible appendage and satisfactory results are obtained. 相似文献
10.
针对火电厂非线性、多变量和多控制目标的特点,设计了一个火电厂多代理控制系统(PPMACS).在PP MACS中,前馈控制代理(FFCAs)采用神经模糊系统进行决策,反馈控制代理(FBCAs)采用基于遗传算法的模糊系统进行决策.优化任务分解代理(OTDAs)通过一个优化代理和一个分解代理来进行多目标优化分解PPMACS的任务.协调代理根据运行条件协调PPMACS的各个代理.仿真结果显示了火电厂多代理控制系统能够实现火电单元机组的多目标运行和大范围负荷跟踪.神经网络、模糊逻辑和遗传算法是PPMACS中的智能代理进行决策的有效工具. 相似文献