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排序方式: 共有518条查询结果,搜索用时 15 毫秒
1.
The message of this research is that in the standard calibrated setting of Computational General Equilibrium (CGE) models, the welfare measures typically used to compare benchmark with counterfactuals are numéraire dependent. This evaluation bias affects the compensating variation and the Konüs index of cost of living. We show that the equivalent variation is neutral regarding the choice of value units in calibrated models but would be affected as well in uncalibrated CGE models. We illustrate with a simple example and propose an even simpler theoretical solution to overcome these biases; all that is required to have correct welfare estimates is to compensate normalizing with a suitable price index. This type of correction is necessary to overcome the sometimes blind implementation of welfare measures in numerical general equilibrium analysis. We show that the induced quantitative errors may be substantial providing biased welfare estimates and misleading results.  相似文献   
2.
Improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To do this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.  相似文献   
3.
This paper examines the behavior of futures prices and trader positions around the occurrence of price limits in commodity futures markets. We ask whether limit events are the result of shocks to fundamental volatility or the result of temporary volatility induced by the trading of noncommercial market participants (speculators). We find little evidence that limits events are the result of speculative activity, but instead associated with shocks to fundamentals that lead to persistent price changes. When futures trading halts price discovery migrates to options markets, but option prices provide a biased estimate of subsequent future prices when trading resumes.  相似文献   
4.
介绍了一种高速宽带采样的数字信号处理平台设计方法,论述了在XilinxV4 FPGA中如何实现高速同步时钟设计和高速数据同步接收设计,介绍了与该设计相关的一些高速模数混合电路设计方法和一种采样后数据捕获的方法。该设计方案已用于瞬时测频中,并取得了良好的效果。  相似文献   
5.
CDMA2000基站以GPS/GLONASS标准秒信号作为整个系统的时钟同步基准,采用一种PLL(锁相环)+DDS(直接数字频率合成器)+PLL的结构实现。引入了时钟同步系统的总体方案。着重介绍了由AD9851和LMX2306构成的后级DDS+PLL的电路设计和参数设置。根据实验结果对该方案的稳定性和适用性进行了分析。  相似文献   
6.
介绍了一种用于大功率IGBT厚膜驱动电路的380V系统输入、多路输出辅助开关电源。该开关电源采用新颖的双管串联模式,解决了高电压输入条件下开关管的选用难题。与传统供电电源相比,该电源电路简单、体积小、重量轻、效率高、允许输入电压范围宽,具有很高的实用价值。该电源已研制成功并已投入实际应用。  相似文献   
7.
为了促进我国通信用高性能电子电路和各种通信ASIC新产品的设计、研制和应用,本文首先论述了性能卓越的BiCMOS技术的先进性,然后讨论了国外流行的两种BiCMOS工艺制作技术及其特殊考虑,以及在通信工程中的应用电路,最后分析了BiCMOS技术在我国高速通信、信息处理电路和系统(如CPU、SRAM、DSP、SOC和数/模混合电路等)中的应用前景和发展趋势。文中提出了运用先进的BiCMOS技术于中国通信电路和系统中的观点。  相似文献   
8.
This paper proposes four criteria for the selection of a better measure of living standards: it should be comprehensive, correlation sensitive, preference based, and fairness based. These criteria are applied to the following measures: income, equivalent income, capabilities, and satisfaction. The paper then explores the relationship between the space of goods and services, the space of budgets, and the more fundamental space of the aspects of life that people really care about. The importance of the fairness principles guiding interpersonal comparisons is highlighted.  相似文献   
9.
介绍了一种利用双音多频(DTMF)信号进行数据通信的接口电路,具体阐述了该电路的组成原理以及软硬件的实现方法.  相似文献   
10.
陈雪峰 《价值工程》2014,33(33):32-33
本文介绍微机计轴自动闭塞在工程中的应用实例,介绍了系统性能、设备安装及调试。  相似文献   
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