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生态效率比率:企业环境绩效审计的新方法 被引量:1
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作者 谢明 仇冬芳 储飞飞 《工业技术经济》 CSSCI 2010年第3期84-87,共4页
根据审计署2008~2012年审计工作发展规划,我国将充分发挥审计在促进企业节能减排措施以及在资源管理与环境保护中的积极作用。企业环境绩效审计的目标既包括监督和评价企业的环境受托责任,又包括激励企业环境管理行为和挖掘企业资源利... 根据审计署2008~2012年审计工作发展规划,我国将充分发挥审计在促进企业节能减排措施以及在资源管理与环境保护中的积极作用。企业环境绩效审计的目标既包括监督和评价企业的环境受托责任,又包括激励企业环境管理行为和挖掘企业资源利用效率潜力。传统的运用于环境绩效审计的指标——生态效率在功能上存在诸多不足;生态效率比率的提出及新的环境绩效审计指标体系的构建可以实现激励企业节能减排和挖掘企业节能减排潜力的功能,实现环境绩效审计的目标。 展开更多
关键词 生态效率比率 环境绩效审计审计目标
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Water Use of Leymus chinensis Community 被引量:6
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作者 宋炳煜 杨劼 +1 位作者 旭日 乌江雨 《Acta Botanica Sinica》 CSCD 2003年第10期1245-1250,共6页
Soil moisture of Leymus chinensis (Trin.) Tzvel. community has obviously stratified phenomena: the layer (0-40 cm) in which roots are concentrically distributed is directly influenced by precipitation and evapotranspi... Soil moisture of Leymus chinensis (Trin.) Tzvel. community has obviously stratified phenomena: the layer (0-40 cm) in which roots are concentrically distributed is directly influenced by precipitation and evapotranspiration. It can be called interaction layer of precipitation and evapotranspiration. The layer (40-120 cm), where water-storage capacity exchange lagged exchange of the root-layer water-storage capacity and the community evapotranspiration, can be called major water-storage layer. The layer (under 120 cm) can be called water relatively stable/balanced layer. The year 1996 was a normal flow year, and soil water had a surplus of 18 mm at the end of the growing season. The year 1998 was a high flow year, because leakage took place under continuous heavy rainfall, soil water had a deficit of 15 mm at the end of the growing season. Transpiration to evapotranspiration ( T/ET) value reflected not only the luxuriance degree of the community, but also the water use regime of the environmental resources. T/ET value was low (0.5) in May 1998, reaching 0.7 in June, then decreasing to 0.6 in July, due to the impact of rainfall inclining, while August reached the maximum (0.9), and September decreased to 0.6. Water use efficiency (WUE) was mainly restricted by the growing rate of plants under sufficient water condition (1998). Its seasonal changes were coincident with the grand period of growth of the plants. When both meanings of WUE and T/ET were analyzed profoundly, the concept of evapotranspiration efficiency (ETE) which can all-side reflect utilization regime of the environmental water resources was advanced. 展开更多
关键词 Leymus chinensis community water use efficiency (WUE) transpiration to evapotranspiration (T/ET) evapotranspiration efficiency (ETE)
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一种新颖的无线网状网的混合调度策略
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作者 马莉 朱光喜 殷伯云 《小型微型计算机系统》 CSCD 北大核心 2011年第5期871-874,共4页
提出一种新颖的时分复用与最大调度的混合调度算法,解决了单信道无线网状网中,当同一时刻待传输链路突增时,信道竞争冲突加剧,网络容量显著下降的问题.算法根据链路与系统子时隙染色,使每条链路都有唯一系统子时隙相对应,链路在同色子... 提出一种新颖的时分复用与最大调度的混合调度算法,解决了单信道无线网状网中,当同一时刻待传输链路突增时,信道竞争冲突加剧,网络容量显著下降的问题.算法根据链路与系统子时隙染色,使每条链路都有唯一系统子时隙相对应,链路在同色子时隙上实现时分复用调度;在异色子时隙空闲时,实现链路的最大调度.此算法具有时分复用和最大调度两种调度算法的优点.文中利用李雅普诺夫稳定性定理证明了算法的效率比率.仿真结果表明,该算法下的网络容量有明显提升. 展开更多
关键词 无线网状网 时分复用 最大调度 效率比率
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Evaluation of the impacts of adaptive cruise control system on improving fuel efficiency of urban road traffic 被引量:2
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作者 李烨 王炜 +2 位作者 王昊 邢璐 刘善文 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期230-235,共6页
The impact of the adaptive cruise control( ACC)system on improving fuel efficiency is evaluated based on the vehicle-specific power. The intelligent driver model was first modified to simulate the ACC system and it ... The impact of the adaptive cruise control( ACC)system on improving fuel efficiency is evaluated based on the vehicle-specific power. The intelligent driver model was first modified to simulate the ACC system and it was calibrated by using empirical traffic data. Then, a five-step procedure based on the vehicle-specific power was introduced to calculate fuel efficiency. Five scenarios with different ACC ratios were tested in simulation experiments, and sensitivity analyses of two key ACC factors affecting the perception-reaction time and time headway were also conducted. The simulation results indicate that all the scenarios with ACC vehicles have positive impacts on reducing fuel consumption. Furthermore, from the perspective of fuel efficiency, the extremely small value of the perception-reaction time of the ACC system is not necessary due to the fact that the value of 0.5 and 0.1 s can almost lead to the same reduction in fuel consumption. Finally, the designed time headway of the ACC system is also proposed to be large enough for fuel efficiency, although its small value can increase capacity. The findings of this study provide useful information for connected vehicles and autonomous vehicle manufacturers to improve fuel efficiency on roadways. 展开更多
关键词 intelligent transportation system vehicle-specific power fuel efficiency ENERGY connected vehicle automated vehicle
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Highly efficient class-F power amplifier with digital predistortion for WCDMA applications 被引量:1
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作者 季连庆 徐志明 +1 位作者 周健义 翟建锋 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期125-128,共4页
A digital predistorted class-F power amplifier (PA) using Cree GaN HEMT CGH40010 operating at 2. 12 GHz is presented to obtain high efficiency and excellent linearity for wideband code-division multiple access ( WC... A digital predistorted class-F power amplifier (PA) using Cree GaN HEMT CGH40010 operating at 2. 12 GHz is presented to obtain high efficiency and excellent linearity for wideband code-division multiple access ( WCDMA ) applications. Measurement results with the continuous wave (CW) signals indicate that the designed class-F PA achieves a peak power-added efficiency (PAE) of 75. 2% with an output power of 39.4 dBm. The adjacent channel power ratio (ACPR) of the designed PA after digital predistortion (DPD) decreases from -28. 3 and -27. 5 dBc to -51.9 and -54. 0 dBc, respectively, for a 4-carrier 20 MHz WCDMA signal with 7. 1 dB peak to average power ratio (PAPR). The drain efficiency (DE) of the PA is 37. 8% at an average output power of 33. 3 dBm. The designed power amplifier can be aoolied in the WCDMA system. 展开更多
关键词 digital predistortion peak power-addedefficiency drain efficiency adjacent channel power ratio EFFICIENCY LINEARITY class-F power amplifier
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Dietary Leucine Requirement of Juvenile Japanese Seabass(Lateolabrax Japonicus) 被引量:3
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作者 LI Yan CHENG Zhenyan +1 位作者 MAI Kangsen AI Qinghui 《Journal of Ocean University of China》 SCIE CAS 2015年第1期121-126,共6页
A 56-day feeding trial was conducted to examine the dietary leucine requirement of juvenile Japanese seabass in sea- water floating net cages (1.5 m × 1.5 m × 2.0 m). Six isonitrogenous (crude protein 40%... A 56-day feeding trial was conducted to examine the dietary leucine requirement of juvenile Japanese seabass in sea- water floating net cages (1.5 m × 1.5 m × 2.0 m). Six isonitrogenous (crude protein 40%) and isoenergetic (gross energy 20 kJ g-1) diets were formulated to contain different concentrations of leucine (0.9%, 1.49%, 2.07%, 2.70%, 3.30% and 3.88% of dry matter). Crys- talline L-amino acids were supplemented to simulate the whole body amino acid pattern of Japanese seabass except for leucine. Three groups (30 fish individuals each, 8.0g±0.20g in initial weight) were fed to apparent satiation at 5:00 and 17:30 every day. During the experimental period, the water temperature ranged from 26 to 32℃ and salinity from 26 to 30, and the dissolved oxygen was maintained at 7mgL-l. The results showed that weight gain (WG), nitrogen retention (NR), feed efficiency (FE) and protein efficiency ratio (PER) were significantly increased when dietary leucine was increased from 0.90% to 2.70% of dry matter, and then declined. WG was the highest when fish were fed D4 containing 2.70% of leucine. No significant differences were observed in body composition among dietary treatments (P 〉 0.05). Considering the change of WG, the optimum dietary leucine requirement of juve- nile Japanese seabass was either 2.39% of dry matter or 5.68% of dietary protein. 展开更多
关键词 GROWTH LEUCINE REQUIREMENT Japanese seabass
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中国对外直接投资的特征及原因探析 被引量:2
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作者 黄玉霞 《武汉商业服务学院学报》 2011年第2期14-19,共6页
近年来我国对外直接投资(Outward Direct Investment)发展迅速。文章分析了我国ODI不均衡发展的特征:ODI规模落后于利用FDI规模;投资集中于资源开发和贸易服务行业;中西部地区ODI发展滞后;投资主要流向亚洲和拉美地区;国有企业投资比例... 近年来我国对外直接投资(Outward Direct Investment)发展迅速。文章分析了我国ODI不均衡发展的特征:ODI规模落后于利用FDI规模;投资集中于资源开发和贸易服务行业;中西部地区ODI发展滞后;投资主要流向亚洲和拉美地区;国有企业投资比例仍较高;并购投资比重还有待提高。同时分析了我国ODI不均衡发展的原因并有针对性地提出相关政策建议。 展开更多
关键词 对外直接投资 跨国并购 心理距离 投资比率效率
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Environmental efficiency and its determinants in the development of China's western regions in 2000-2014
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作者 Chuanbin Yin 《Chinese Journal of Population,Resources and Environment》 2017年第2期157-166,共10页
In this study, we measure the environmental efficiency of western China in 2000-2014 by the super-efficiency slacks-based measure model which considers the undesirable outputs. The results show that the environmental ... In this study, we measure the environmental efficiency of western China in 2000-2014 by the super-efficiency slacks-based measure model which considers the undesirable outputs. The results show that the environmental efficiency of western China is low and rank behind in the national level. The environmental efficiency is lower than the traditional efficiency which reflects that the economic growth in 2000-2014 has paid high environmental costs. The difference between the traditional efficiency and environmental efficiency experienced "inverted U"-type trend change. The environmental efficiency of the western provinces presented differentiated developing trend and the differences between the western provinces were enlarging. The environmental efficiency of the western regions was not only lower than that in the eastern regions with a big gap but also lower than that in the central regions. Through the convergence test, we found that the environmental efficiency gap between the western and the eastern regions was gradually expanding; meanwhile, the environmental efficiency gap between the central and the western regions was narrowing. This paper also analyzes the determinants of environmental efficiency by the tobit model and then addresses. 展开更多
关键词 Western China environmental efficiency super-efficiency SBM determinants
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Computational Film Cooling Effectiveness of Dual Trench Configuration on Flat Plate at Moderate Blowing Ratios
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作者 Antar M.M. Abdala Qun Zheng Fifi N.M. Elwekeel Ping Dong 《Journal of Marine Science and Application》 2013年第2期208-218,共11页
In the present work, computational simulations was made using ANSYS CFX to predict the improvements in film cooling performance with dual trench. Dual-trench confguradon consists of two trenches together, one wider tr... In the present work, computational simulations was made using ANSYS CFX to predict the improvements in film cooling performance with dual trench. Dual-trench confguradon consists of two trenches together, one wider trench and the other is narrow trench that extruded from the wider one. Several blowing ratios in the range (0.5:5) were investigated. The pitch-to-diameter ratio of 2.775 is used. By using the dual trench configuration, the coolant jet impacted the trench wall two times allowing increasing the spreading of coolant laterally in the trench, reducing jet velocity and jet completely covered on the surface. The results indicate that this configuration increased adiabatic effectiveness as blowing ratio increased. The spatially averaged adiabatic effectiveness reached 57.6% for at M= 2. No observed film blow-off at all blowing ratios. The adiabatic film effectiveness of dual trench case outperformed the narrow trench case, laidback fan-shaped hole, fan-shaped hole and cylinder hole at different blowing ratios. 展开更多
关键词 gas turbine dual-trench film cooling adiabatic effectiveness jet interaction phenomena flat plate moderate blowing ratios
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论人力资源会计的理论体系
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作者 刘懿 《湖南财政与会计》 1999年第2期24-26,共3页
以人力资源及价值为核算对象的人力资源会计产生于六十年代的美国,美国会计学会(AAA)在1973年的报告中认为“人力资源会计是对人力资源进行确认和计量,并将其结果报告给有利害关系各方面的报告”。它的产生是由于人力资源作为最重要的... 以人力资源及价值为核算对象的人力资源会计产生于六十年代的美国,美国会计学会(AAA)在1973年的报告中认为“人力资源会计是对人力资源进行确认和计量,并将其结果报告给有利害关系各方面的报告”。它的产生是由于人力资源作为最重要的生产要素,越来越受到各政府和管理阶层的关注。 展开更多
关键词 人力资源会计 人力资源成本 人力资源价值 经济价值 会计目标 效率比率 重置成本 投资报酬率 会计理论体系 会计假设
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A Monolithic InGaP/GaAs HBT PA for TD-SCDMA Handset Application 被引量:1
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作者 毕晓君 张海英 +1 位作者 陈立强 黄清华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第10期1868-1872,共5页
This paper demonstrates the design and fabrication of a monolithic HBT power amplifier for TD-SCDMA cellu- lar phones that achieves high efficiency and linearity. The two-stage MMIC integrates the input matching circu... This paper demonstrates the design and fabrication of a monolithic HBT power amplifier for TD-SCDMA cellu- lar phones that achieves high efficiency and linearity. The two-stage MMIC integrates the input matching circuits,interstage matching circuits, and active bias circuits in a single chip with size as small as 0.91mm × 0.98mm. The amplifier obtains a power-added efficiency of 43% (15%) and a gain of 28.5dB (24dB) at the high and low operation mode under the 3.4V supply. In addition, the adjacent channel leakage power is below - 45dBc/- 56dBc and - 39dBc/- 50dBc at 1.6MHz/3.2MHz offset in low and high power output modes, respectively, with QPSK modulation. The MMIC offers the potential for low cost production due to small chip size, stable voltage supply, and high performance at the same time. 展开更多
关键词 rD-SCDMA power amplifier InGaP/GaAs HBT PAE ACPR
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Efficiency comparison and performance analysis of internally-cooled liquid desiccant dehumidifiers using LiCl and CaCl2 aqueous solutions 被引量:2
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作者 Dong-gen PENG Shun-yi LI +3 位作者 Dan-ting LUO Yu-ting FU Xiao-song CHENG Yin LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2020年第1期44-63,共20页
Internally-cooled dehumidifiers are efficient liquid desiccant dehumidifiers, whose performance is mainly determined by the device structure and operating conditions. Based on energy and mass conservation in the air, ... Internally-cooled dehumidifiers are efficient liquid desiccant dehumidifiers, whose performance is mainly determined by the device structure and operating conditions. Based on energy and mass conservation in the air, solution, and cooling water in the device, mathematical models are built and their theoretical performance is simulated and analyzed in this paper. A novel measure of dehumidification efficiency is introduced to evaluate the performance of internally-cooled dehumidifiers, in which the equilibrium humidity ratio of the inlet solution is calculated according to the minimum temperature in the inlet solution and the cooling water. Numerical simulations show that a counter flow between air and solution is always the most efficient, followed by cross flow, and parallel flow is the least efficient. Cooling water with the same flow direction as the solution performs better than that with a counter flow, with approximately a 5% improvement in efficiency. Compared with Ca Cl2, the dehumidification efficiency of a Li Cl solution is greater by 60%, while its exergy efficiency is less by 16%. Dehumidification efficiency can be improved with the number of air-solution heat transfer units(NTUa-s) increasing, and reduced with the air mass flow rate raised. With NTUa-s increasing, exergy efficiency can be improved, and an increase in mass flow rate of cooling water results in a decrease of efficiency. Higher solution concentration and lower inlet temperature of solution and air can achieve both higher dehumidification efficiency and exergy efficiency. 展开更多
关键词 Liquid desiccant Internally-cooled dehumidifiers Performance comparison Dehumidification efficiency Exergy efficiency
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