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41.
In this paper the author will present the working principle and the applications of a novel adaptive biasing topology, designed to decrease the stand-by power dissipation without affecting the transient performance of low-power amplifiers. The proposed circuit, whose principle and circuit topology can be implemented both in CMOS and in bipolar standard technologies, gives a biasing current whose value depends on the applied input differential voltage and can be set according to the requested transient performance constraints. The adaptive architecture can be utilized in the design of high-efficient low-power operational amplifiers, for the biasing of both the input stage (where the input source current is dynamically increased) and the output stage (where the output current can be controlled and limited). These amplifiers show a very good behaviour, evaluated in terms of two efficiency factors, if compared with those of other adaptive solutions and class-AB topologies, proposed in the literature. Simulation results and also measurements on a chip prototype, fabricated in a standard CMOS technology, are finally presented.  相似文献   
42.
In this paper, we introduce the LOPOCOS (Low Power Co-synthesis) system, a prototype CAD tool for system level co-design. LOPOCOS targets the design of energy-efficient embedded systems implemented as heterogeneous distributed architectures. In particular, it is designed to solve the specific problems involved in architectures that include dynamic voltage scalable (DVS) processors. The aim of this paper is to demonstrate how LOPOCOS can support the system designer in identifying energy-efficient hardware/software implementations for the desired embedded systems. Hence, highlighting the necessary optimization steps during design space exploration for DVS enable architectures. The optimization steps carried out in LOPOCOS involve component allocation and task/communication mapping as well as scheduling and dynamic voltage scaling. LOPOCOS has the following key features, which contribute to this energy efficiency. During the voltage scaling valuable power profile information of task execution is taken into account, hence, the accuracy of the energy estimation is improved. A combined optimization for scheduling and communication mapping based on genetic algorithm, optimizes simultaneously execution order and communication mapping towards the utilization of the DVS processors and timing behaviour. Furthermore, a separation of task and communication mapping allows a more effective implementation of both task and communication mapping optimizationsteps. Extensive experiments are conducted to demonstrate the efficiency of LOPOCOS. We report up to 38% higher energy reductions compared to previous co-synthesis techniques for DVS systems. The investigations include a real-life example of an optical flow detection algorithm.  相似文献   
43.
With worldwide energy consumption rising, there is a need to reduce energy use of the housing stock. While this general idea is well-known, there is an overwhelming amount of product data and manufacturers claims through which the homebuilder or designer must sort to make informed selections of energy-efficient upgrades. The main objective of this research was to identify cost effective–energy efficient upgrades from a group of 16 commonly available choices, and rank them according to the most beneficial for the least cost. This study was conducted in Phoenix, Arizona, and included a sample of 30 production-style homes typical of the Phoenix metropolitan area. Energy-simulation software was used to perform energy evaluations and derive the benefits of each upgrade. The cost of each upgrade was obtained from a database of national average costs and from a local context. Differences in the selection of beneficial upgrades vary dramatically with the source of the cost information. This research provides a generic methodology that can be used by builders and designers to select appropriate energy-efficient upgrades for a given geographic area that will provide high operating benefits relative to the amount of capital investment.  相似文献   
44.
广州市住宅直饮水设计定额的确定   总被引:1,自引:0,他引:1  
对住宅直饮水系统的实际运营情况进行了分析,运营中出现的销售水量低于直饮水定额、制水设备实际工作时间低于额定时间及水表工作不正常等现象都反映了现行直饮水设计定额的不合理性,建议将用水量定额定为5~8L/(户·d),既符合实际情况又能满足居民远期需求。  相似文献   
45.
In this study forecast of Turkey's net electricity energy consumption on sectoral basis until 2020 is explored. Artificial neural networks (ANN) is preferred as forecasting tool. The reasons behind choosing ANN are the ability of ANN to forecast future values of more than one variable at the same time and to model the nonlinear relation in the data structure. Founded forecast results by ANN are compared with official forecasts.  相似文献   
46.
《Drying Technology》2007,25(11):1803-1808
Malting is a very intensive, energy-consuming process and, from the point of view of energy, green malt drying is one of the most important operations. Double-deck kiln drying, a variant of single-deck kiln drying, is the most commonly used process, but it is usually manually controlled under empirical control actions. These are the reasons why a research project was carried out based on the computer modeling of these process operations including a software tool named CIMFOOD. A knowledge-based system (KBS) allowing the entire processing-plant dynamic behavior simulation and scheduling concerning thermal energy requirements was developed.  相似文献   
47.
Asynchronous design techniques have a number of compelling features that make them suited for complex system on chip designs. However, it is necessary to develop practical and efficient design techniques to overcome the present shortage of commercial design tools. This paper describes the development of CADRE (Configurable Asynchronous DSP for Reduced Energy), a 750K transistor, high performance, low-power digital signal processor IP block intended for digital mobile phone chipsets. A short time period was available for the project, and so a methodology was developed that allowed high-level simulation of the design at the earliest possible stage within the conventional schematic entry environment and simulation tools used for later circuit-level performance and power consumption assessment. Initial modeling was based on C behavioral models of the various data and control components, with the many asynchronous control circuits required automatically generated from their specifications. This has enabled design options to be explored and unusual features of the design, such as the Register Bank which is designed to exploit data access patterns, are presented along with the power and performance results of the processor as a whole.  相似文献   
48.
催化裂化装置反应再生系统优化改造   总被引:3,自引:0,他引:3  
重点介绍了呼和浩特石油化工公司重油催化裂化装置反应再生系统优化改造的目的、内容及运用的新技术;着重从物料平衡、原料及产品性质、催化剂性质、装置能耗、操作参数等方面与改造前进行了对比。装置改造后,在原料明显变重,催化剂单耗明显降低的情况下,生焦率下降了0.13个百分点,轻质油收率提高了3.54个百分点;汽油诱导期较改造前延长了140min,烯烃体积分数降低了1.9个百分点;柴油十六烷值比改造前提高了4个单位;装置能耗较改造前下降了906MJ/t,年创经济效益1030.9×10~4RMB¥。  相似文献   
49.
为探索山丘地区中小型泵站技术改造的经验,选定南康县四个小型泵站作为泵站改造的试点站,进行现场测试,根据测试成果,分析各站存在的问题及效率偏低的原因,并拟定各站技术改造的措施,经实施后取得了较好的效果,本文就南康县泵站改造的实际效果阐明泵站改造的必要性及其改造过程中值得注意的问题。  相似文献   
50.
《Drying Technology》2007,25(1):75-84
This article proposes a multiscale computational model able to calculate energy consumption in a batch lumber kiln. A dual-scale computational model of wood drying deals with the boards/stack interaction and serves as a basis for the present work. A new module was added here that calculates heat losses through kiln walls (convection, condensation) and the energy used by each kiln component (fans, heating elements, humidifier, vacuum pump, etc.). The corresponding mathematical formulation is presented and then theoretical results are compared to those collected in an industrial vacuum kiln. As application example, the effect of air reversal, air velocity, and kiln insulation are exhibited, which depicts the great potential and prospects of this new tool for energy savings in relation to the product quality.  相似文献   
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