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A multi-objective fuzzy optimization model for cropping structure and water resources and its method 被引量:3
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作者 马建琴 陈守煜 邱林 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期5-10,共6页
Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this... Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development. 展开更多
关键词 cropping structure multi objective fuzzy optimization fuzzy deciding weight agricultural water resources
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Power Allocation for Sensing-Based Spectrum Sharing Cognitive Radio System with Primary Quantized Side Information
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作者 Shuying Zhang Xiaohui Zhao 《China Communications》 SCIE CSCD 2016年第9期33-43,共11页
Spectrum access approach and power allocation scheme are important techniques in cognitive radio(CR) system,which not only affect communication performance of CR user(secondary user,SU) but also play decisive role for... Spectrum access approach and power allocation scheme are important techniques in cognitive radio(CR) system,which not only affect communication performance of CR user(secondary user,SU) but also play decisive role for protection of primary user(PU).In this study,we propose a power allocation scheme for SU based on the status sensing of PU in a single-input single-output(SISO) CR network.Instead of the conventional binary primary transmit power strategy,namely the sensed PU has only present or absent status,we consider a more practical scenario when PU transmits with multiple levels of power and quantized side information known by SU in advance as a primary quantized codebook.The secondary power allocation scheme to maximize the average throughput under the rate loss constraint(RLC) of PU is parameterized by the sensing results for PU,the primary quantized codebook and the channel state information(CSI) of SU.Furthermore,Differential Evolution(DE) algorithm is used to solve this non-convex power allocation problem.Simulation results show the performance and effectiveness of our proposed scheme under more practical communication conditions. 展开更多
关键词 cognitive radio power allocation multi-level spectrum sensing quantized side information differential evolution
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Non-dominated sorting quantum particle swarm optimization and its application in cognitive radio spectrum allocation 被引量:4
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作者 GAO Hong-yuan CAO Jin-long 《Journal of Central South University》 SCIE EI CAS 2013年第7期1878-1888,共11页
In order to solve discrete multi-objective optimization problems, a non-dominated sorting quantum particle swarm optimization (NSQPSO) based on non-dominated sorting and quantum particle swarm optimization is proposed... In order to solve discrete multi-objective optimization problems, a non-dominated sorting quantum particle swarm optimization (NSQPSO) based on non-dominated sorting and quantum particle swarm optimization is proposed, and the performance of the NSQPSO is evaluated through five classical benchmark functions. The quantum particle swarm optimization (QPSO) applies the quantum computing theory to particle swarm optimization, and thus has the advantages of both quantum computing theory and particle swarm optimization, so it has a faster convergence rate and a more accurate convergence value. Therefore, QPSO is used as the evolutionary method of the proposed NSQPSO. Also NSQPSO is used to solve cognitive radio spectrum allocation problem. The methods to complete spectrum allocation in previous literature only consider one objective, i.e. network utilization or fairness, but the proposed NSQPSO method, can consider both network utilization and fairness simultaneously through obtaining Pareto front solutions. Cognitive radio systems can select one solution from the Pareto front solutions according to the weight of network reward and fairness. If one weight is unit and the other is zero, then it becomes single objective optimization, so the proposed NSQPSO method has a much wider application range. The experimental research results show that the NSQPS can obtain the same non-dominated solutions as exhaustive search but takes much less time in small dimensions; while in large dimensions, where the problem cannot be solved by exhaustive search, the NSQPSO can still solve the problem, which proves the effectiveness of NSQPSO. 展开更多
关键词 cognitive radio spectrum allocation multi-objective optimization non-dominated sorting quantum particle swarmoptimization benchmark function
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Joint channel allocation and power control with fairness in multi-hop cognitive radio networks
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作者 裴雪兵 Tang Zhenhua 《High Technology Letters》 EI CAS 2015年第3期315-320,共6页
This paper investigates channel allocation and cognitive radio networks. The color-sensitive graph power control schemes in OFDM-based multi-hop coloring (CSGC) model is viewed as an efficient solution to the spectr... This paper investigates channel allocation and cognitive radio networks. The color-sensitive graph power control schemes in OFDM-based multi-hop coloring (CSGC) model is viewed as an efficient solution to the spectrum assignment problem. The model is extended to combine with the power con- trol strategy to avoid interference among secondary users and adapt dynamic topology. The optimiza- tion problem is formulated encompassing the channel allocation and power control with the interfer- ence constrained below a tolerable limit. Meanwhile, the proposed resource allocation scheme takes the fairness of secondary users into account in obtaining the solution of optimization. Numerical re- suits show that the proposed strategy outperforms the existing spectrum assignment algorithms on the performance of both the network throughput and minimum route bandwidth of all routes, as well as the number of connected multi-hop routes which implies the fairness among secondary users. 展开更多
关键词 channel allocation power control multi-hop cognitive radio networks
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Relationship between alumina mixing characteristics and feeder configurations in aluminum reduction cells 被引量:3
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作者 Hong-liang ZHANG Shuai YANG Jie LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第11期2512-2520,共9页
Because of the increasingly prominent problem of alumina content inhomogeneity in large or super-scale aluminum reduction cells,a transient numerical model for the alumina mixing process was developed for a400kA cell,... Because of the increasingly prominent problem of alumina content inhomogeneity in large or super-scale aluminum reduction cells,a transient numerical model for the alumina mixing process was developed for a400kA cell,and the relationship between the alumina content distribution and electrolyte flow field was analyzed.In the ANSYS software platform,several numerical simulation cases were presented to display the influence of the feeder configuration on the alumina mixing characteristics.The results showed that a large vortex flow of the molten electrolyte is beneficial for alumina mixing and uniform distribution in the inner areas of the vortexes.The alumina particles reach the inter-electrode zone in10?15s from the beginning of the feeding action,and the risk of early precipitation occurs in10?25s after the feeding.It was also found that a suitable grouping of feeders could reduce the content fluctuation and gradient.Therefore,a feeding on demand strategy was proposed,and the simulation results showed that although the spatial characteristics are not changed,the uniformity of the alumina content was markedly improved. 展开更多
关键词 aluminum electrolysis content distribution feeder configuration alumina precipitation
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Effect of CO Combustion Promoters on Combustion Air Partition in FCC under Nearly Complete Combustion 被引量:3
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作者 王锐 罗雄麟 许锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第5期531-537,共7页
With CO combustion promoters, the role of combustion air flow rate for concerns of economics and control is important. The combustion air is conceptually divided to three parts: the air consumed by coke burning,the ai... With CO combustion promoters, the role of combustion air flow rate for concerns of economics and control is important. The combustion air is conceptually divided to three parts: the air consumed by coke burning,the air consumed by CO combustion and the air unreacted. A mathematical model of a fluid catalytic cracking(FCC)unit, which includes a quantitative correlation of CO heterogeneous combustion and the amount of CO combustion promoters, is introduced to investigate the effects of promoters on the three parts of combustion air. The results show that the air consumed by coke burning is almost linear to combustion air flow rate, while the air consumed by CO combustion promoters tends to saturate as combustion air flow rate increases, indicating that higher air flow rate can only be used as a manipulated variable to control the oxygen content for an economic concern. 展开更多
关键词 fluid catalytic cracking unit CO combustion promoters combustion air partition
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Heterogeneous Quality of Experience Guarantees Over Wireless Networks 被引量:1
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作者 Jianyu Wang Wenchi Cheng 《China Communications》 SCIE CSCD 2018年第10期51-59,共9页
Quality of experience(Qo E), which is very critical for the experience of users in wireless networks, has been extensively studied. However, due to different human perceptions, quantifying the effective capacity of wi... Quality of experience(Qo E), which is very critical for the experience of users in wireless networks, has been extensively studied. However, due to different human perceptions, quantifying the effective capacity of wireless network subject to diverse Qo E is very difficult, which leads to many new challenges regarding Qo E guarantees in wireless networks. In this paper, we formulate the Qo E guarantees model for cellular wireless networks. Based on the model, we convert the effective capacity maximization problem into the equivalent convex optimization problem. Then, we develop the optimal Qo E-driven power allocation scheme, which can maximize the effective capacity. The obtained simulation results verified our proposed power allocation scheme, showing that the effective capacity can be significantly increased compared with that of traditional Qo E guarantees based schemes. 展开更多
关键词 wireless network effective capacity power allocation HETEROGENEOUS qualityof experience quality of service
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Systematical Study on Photodissociation Dynamics of BrCN from 225 nm to 260 nm
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作者 Tonghui Yin Liying Ma +1 位作者 Hong Gao Min Cheng 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第1期86-94,I0063,共10页
The photodissociation dynamics of Br-C bond cleavage for BrCN in the wavelength region from 225 nm to 260 nm has been studied by our homebuilt time-slice velocity-map imaging setup.The images for both of the ground st... The photodissociation dynamics of Br-C bond cleavage for BrCN in the wavelength region from 225 nm to 260 nm has been studied by our homebuilt time-slice velocity-map imaging setup.The images for both of the ground state Br(^(2)P_(3/2))and spin-orbit excited Br^(*)(^(2)P_(1/2))channels are obtained at several photodissociation wavelengths.From the analysis of the translational energy release spectra,the detailed vibrational and rotational distributions of CN products have been measured for both of the Br and Br^(*) channels.It is found that the internal excitation of the CN products for the Br^(*) channel is colder than that for the Br channel.The most populated vibrational levels of the CN products are v=0 and 1 for the Br and Br^(*) channels,respectively.For the Br channel,the photodissociation dynamics at longer wavelengths are found to be different from those at shorter wavelengths,as revealed by their dramatically different vibrational and rotational excitations of the CN products. 展开更多
关键词 Photodissociation dynamics Cyanogen bromide Ro-vibronic distribution Energy partitioning Velocity-map imaging
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Accounting and Responsibility Allocation on Carbon Emissions Embodied in International Trade 被引量:1
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《China Economist》 2012年第2期50-59,共10页
This paper calculated the scale of carbon emissions embodied in the import and export of the world's major countries based on input-output principles and international trade data, as well as data on various countries... This paper calculated the scale of carbon emissions embodied in the import and export of the world's major countries based on input-output principles and international trade data, as well as data on various countries'carbon emissions in 2005 from domestic consumption and emissions embodied in trade. The results illustrate that, because of international trade, consumers in developed countries should bear the responsibility for a large portion of CO2 emissions. The researchers separated the net transfer balance of embodied emissions in international trade according to four different effects: size effect, exchange rate effect, structural effect, and pure technical effect, all of which favor the sharing of responsibilities between producers and consumers. 展开更多
关键词 embodied carbon emissions international trade net transfer Logarithmic an Divisia Index (LMDI)JEL: Q48
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Embodied Energy and CO2 Associated with Buildings by Using Input and Output Table in Japan
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作者 Noriyoshi Yokoo Tatsuo Oka +2 位作者 Keizo Yokoyama Takao Sawachi Makoto Yamamoto 《Journal of Civil Engineering and Architecture》 2015年第2期153-164,共12页
In July 2009, the 2005 basic Japanese input/output table was publicized together with its physical transaction table. This research paper analyzed the 2005 IO (input/output) table to create building industry-related... In July 2009, the 2005 basic Japanese input/output table was publicized together with its physical transaction table. This research paper analyzed the 2005 IO (input/output) table to create building industry-related intensities and, at the same time, compared the building industry with industries at large for distribution margins and transportation. The analysis of distribution margins separately for middle and purchaser margins found that middle margins in the building industry are minor at 35% of the averages for all industries, while purchaser margins are sizable at 1.8 times, proving that it is an industry for which local production for local consumption is quite effective. CO2 emissions resulting from transportation in the building industry were calculated and concisely characterized. Although the ratio of transportation CO2 emissions to total CO2 emissions in each industry finds almost no difference between general industries and the building industry, transportation CO2 emissions per production value are two to three times heavier than those from general industries to be justified as a transportation-intensive industry. 展开更多
关键词 Embodied energy embodied CO2 input and output table.
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Attitude control allocation strategy of high altitude airship based on synthetic performance optimization 被引量:1
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作者 遆晓光 韩放 姚郁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期746-750,共5页
This paper presents a method for solving the attitude control problem of high altitude airship (HAA) with aerodynamic fin and vectored thruster control. The algorithm is based on the synthetic optimization of dynamic ... This paper presents a method for solving the attitude control problem of high altitude airship (HAA) with aerodynamic fin and vectored thruster control. The algorithm is based on the synthetic optimization of dynamic performance and energy consumption of airship. Firstly, according to the system overall configuration, the dynamic model of HAA was established and the HAA linearized model of longitudinal plane motion was obtained. Secondly, using the classic PID control theory, the HAA attitude control system was designed. Thirdly, through analyzing the dynamic performance of airship with fin or vectored thruster control, the synthetic performance index function with different weighting functions was determined. By means of optimizing the obtained performance index function, the attitude control of high altitude airship with good dynamic performance and low energy consumption was achieved. Finally, attitude control allocation strategy was designed for the airship station keeping at an altitude of 22 km. The simulation experiment proved the validity of the proposed algorithm. 展开更多
关键词 high altitude airship attitude control synthetic performance optimization control strategy
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Effect of modified Taohongsiwu decoction on patients with chemotherapy-induced hand-foot syndrome 被引量:19
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作者 Changlin Zhao Jia Chen +4 位作者 Bin Yu Xianlin Wu Congqi Dai Chang Zhou Xiaoyin Chen 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第1期10-14,共5页
OBJECTIVE:To observe the effect of the Traditional Chinese Medicine,modified Taohongsiwu decoction,versus pyridoxine on patients with hand-foot syndrome(HFS)from capecitabine,sorafenib,and gefitinib chemotherapy for g... OBJECTIVE:To observe the effect of the Traditional Chinese Medicine,modified Taohongsiwu decoction,versus pyridoxine on patients with hand-foot syndrome(HFS)from capecitabine,sorafenib,and gefitinib chemotherapy for gastric,lung,breast,colon,or rectal cancer.Also,to compare quality of life of patients in each group.METHODS:Patients were assigned randomly to group A or B.Group A was given modifiedTaohongsiwu decoction to soak hands and feet for 30 min,once daily.Group B was given 100 mg pyridoxine orally,twice daily.After a 2-week treatment,thetherapeutic effect was assessed by observing three major symptoms,including pain,ulceration,and muscular atrophy.This was assessed with the HFS-14 questionnaire.RESULTS:Significant differences were observed between the two groups in pain relief,and improvement of daily life,walking,and interpersonal communication(P<0.01).No significant differences in driving ability or interpersonal relationships were found.After 2 weeks,the effective rate was 88.3%in group A,which was significantly higher than the50%in group B(P=0.00).CONCLUSION:Modified Taohongsiwu decoction is effective in the treatment of patients with HFS.It improves patients'quality of life according to the HFS-14. 展开更多
关键词 NEOPLASMS Hand-foot syndrome Mod-ifiedTaohongsiwu decoction Quality of life
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“都”:基于量级隐涵和焦点结构的统一解释 被引量:2
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作者 李可胜 《当代语言学》 北大核心 2023年第4期475-499,共25页
现有文献对“都”的研究存在量化说和隐涵说两种理论流派,前者将“都”视为量化-分配算子,后者将“都”视为隐涵标记。前者总体上更占优势,但面临“双重约束”这一无法规避的根本性问题。一些学者从量级隐涵的视角试图给出“都”的统一... 现有文献对“都”的研究存在量化说和隐涵说两种理论流派,前者将“都”视为量化-分配算子,后者将“都”视为隐涵标记。前者总体上更占优势,但面临“双重约束”这一无法规避的根本性问题。一些学者从量级隐涵的视角试图给出“都”的统一解释,但并没有撼动量化说。主要原因是隐涵说自身还存在问题,“都”的很多特性还无法被隐涵说解释。基于选项语义学,本文提出“都”只是表示最大预期义和超预期义的语用隐涵标记,并无量化-分配作用。但因“都”字句中存在三种基本焦点结构以及一种拓展的焦点结构,因而造成了多种不同的语义表现,如“都”的不同语义指向,聚合-分配解的转换以及允准疑问词成为任选项等。 展开更多
关键词 量级隐涵(SI) 量化-分配 “都”字句 焦点结构 选项语义学
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Anharmonic vibrations of nucleobases: Structural basis of one-and two-dimensional infrared spectra for canonical and mismatched base pairs
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作者 WANG GuiXiu ZHAO Juan WANG JianPing 《Science China Chemistry》 SCIE EI CAS 2011年第10期1590-1606,共17页
Canonical Watson-Crick base pairs and four representative mismatched base pairs have been studied by quantum chemical computations. Detailed anharmonic vibrational analysis was carried out to reveal some vibrational s... Canonical Watson-Crick base pairs and four representative mismatched base pairs have been studied by quantum chemical computations. Detailed anharmonic vibrational analysis was carried out to reveal some vibrational signatures characteristic of structural aspects of the base monomers and dimers, which were well manifested in simulated 1D IR and 2D IR spectra. The degree of delocalization of the selected normal modes, represented by the potential energy distribution, was found to vary sig-nificantly from isolated bases to H-bonded dimers, and was accompanied by changes in anharmonicities of these modes. Examples are given for the generally accepted carbonyl stretching mode of base pairs appearing in the 6-m wavelength region of IR spectra. 展开更多
关键词 quantum chemical computation canonical Watson–Crick base pair mismatched base pair anharmonic vibration infrared
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