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B样条函数 1

REITs 型公共租赁住房 1

下降敲入期权 1

二维波达角估计；信道冲击响应估计；信号检测；均匀矩形阵列；大规模天线 1

互联网体系结构 1

人工智能 1

人群计数；密度估计；分割先验图；均匀函数 1

人脸建模 1

以内容为中心 1

价格机制 1

住房特征 1

双圈均匀圆阵；幅相误差；位置误差；互耦误差；校正 1

双驱动网络 1

圆柱 1

地址驱动 1

均匀流形逼近和投影 1

均匀照度分布 1

基于内容的卫星图像配准；特征点分布；图像配准；线性判别准则；遥感；尺度不变特征变换 1

多分辨率分析 1

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Nodal, zonal, or uniform electricity pricing: how to deal with network congestion

Martin WEIBELZAHL

《能源前沿（英文）》 2017年第11卷第2期页码 210-232 doi: 10.1007/s11708-017-0460-z

摘要： In this paper, the main contributions to congestion management and electricity pricing, i.e., nodal, zonal, and uniform electricity pricing, are surveyed. The key electricity market concepts are structured and a formal model framework is proposed for electricity transportation, production, and consumption in the context of limited transmission networks and competitive, welfare maximizing electricity markets. In addition, the main results of existing short-run and long-run congestion management studies are explicitly summarized. In particular, the important interconnection between short-run network management approaches and optimal long-run investments in both generation facilities and network lines are highlighted.

关键词： nodal pricing zonal pricing uniform pricing competitive electricity markets welfare maximization redispatch optimization models

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REITs 型公共租赁住房租金定价模型设计

王林秀,曾兰,陶飞

《中国工程科学》 2014年第16卷第10期页码 94-99

摘要：

借鉴国外公共租赁住房租金定价经验，制定租金定价策略；在分析房地产投资信托基金（REITs）型公共租赁住房租金构成的基础上，参照普通住房价格制定的基本理论方法，采用综合性定价方法，构建一种面向低收入人群中的相对高收入人群或暂时性低收入人群、兼顾成本及住房特征的科学性定价模型。该定价模型充分考虑到项目建设的直接成本、入住者的差异性需求及大众投资者投资期望，综合多方需求，为科学合理制定租金提供依据。

关键词： REITs 型公共租赁住房住房特征定价方法定价模型设计

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Assessment indices for uniform and non-uniform thermal environments

ZHANG Yufeng, SUN Shufeng, ZHAO Rongyi

《能源前沿（英文）》 2008年第2卷第2期页码 129-133 doi: 10.1007/s11708-008-0029-y

摘要： Different assessment indices for thermal environments were compared and selected for proper assessment of indoor thermal environments. 30 subjects reported their overall thermal sensation, thermal comfort, and thermal acceptability in uniform and non-uniform conditions. The results show that these three assessment indices provide equivalent evaluations in uniform environments. However, overall thermal sensation differs from the other two indices and cannot be used as a proper index for the evaluation of non-uniform environments. The relationship between the percentage and the mean vote for each index is established.

关键词： thermal sensation proper assessment relationship equivalent thermal acceptability

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Robust isogeometric topology optimization for piezoelectric actuators with uniform manufacturability

《机械工程前沿（英文）》 2022年第17卷第2期 doi: 10.1007/s11465-022-0683-5

摘要： Piezoelectric actuators have received substantial attention among the industry and academia due to quick responses, such as high output force, high stiffness, high accuracy, and precision. However, the design of piezoelectric actuators always suffers from the emergence of several localized hinges with only one-node connection, which have difficulty satisfying manufacturing and machining requirements (from the over- or under-etching devices). The main purpose of the current paper is to propose a robust isogeometric topology optimization (RITO) method for the design of piezoelectric actuators, which can effectively remove the critical issue induced by one-node connected hinges and simultaneously maintain uniform manufacturability in the optimized topologies. In RITO, the isogeometric analysis replacing the conventional finite element method is applied to compute the unknown electro elastic fields in piezoelectric materials, which can improve numerical accuracy and then enhance iterative stability. The erode–dilate operator is introduced in topology representation to construct the eroded, intermediate, and dilated density distribution functions by non-uniform rational B-splines. Finally, the RITO formulation for the design of piezoelectric materials is developed, and several numerical examples are performed to test the effectiveness and efficiency of the proposed RITO method.

关键词： piezoelectric actuator isogeometric topology optimization uniform manufacturability robust formulation density distribution function

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Effect of non-uniform illumination on performance of solar thermoelectric generators

Ershuai YIN, Qiang LI, Yimin XUAN

《能源前沿（英文）》 2018年第12卷第2期页码 239-248 doi: 10.1007/s11708-018-0533-7

摘要： Solar thermoelectric generators (STEGs) are heat engines which can generate electricity from concentrated sunlight. The non-uniform illumination caused by the optical concentrator may affect the performance of solar thermoelectric generators. In this paper, a three-dimensional finite element model of solar thermoelectric generators is established. The two-dimensional Gaussian distribution is employed to modify the illumination profiles incident on the thermoelectric generator. Six non-uniformities of solar illumination are investigated while keeping the total energy constant. The influences of non-uniform illumination on the temperature distribution, the voltage distribution, and the maximum output power are respectively discussed. Three thermoelectric generators with 32, 18 and 8 pairs of thermocouples are compared to investigate their capability under non-uniform solar radiation. The result shows that the non-uniformity of the solar illumination has a great effect on the temperature distribution and the voltage distribution. Central thermoelectric legs can achieve a larger temperature difference and generate a larger voltage than peripheral ones. The non-uniform solar illumination will weaken the capability of the TE generator, and the maximum output power decrease by 1.4% among the range of non-uniformity studied in this paper. Reducing the number of the thermoelectric legs for non-uniform solar illumination can greatly increase the performance of the thermoelectric generator.

关键词： solar thermoelectric generators non-uniform solar illumination performance evaluation solar energy

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Controlled synthesis of uniform silver nanowires with high aspect ratios in aqueous solutions of gemini

XU Jian, LIU Weijun, LIU Honglai, HU Ying

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 221-227 doi: 10.1007/s11705-007-0040-6

摘要： A simple solution-phase approach has been demonstrated for the large-scale synthesis of silver nanowires with diameters in the range of 15 25 nm, and lengths usually in the range of tens of micrometers. In the presence of gemini surfactant 1,3-bis(cetyldimethylammonium) propane dibromide (16-3-16), the growth of silver could be directed into a highly anisotropic mode to form uniform nanowires with aspect ratios up to about 2,000. X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), X-ray powder diffraction (XRD), electron diffraction (ED), and UV-vis absorption spectroscopy, were used to characterize the as-prepared silver nanowires, indicating the formation of a highly pure phase, good crystallinity, as well as a uniform diameter.

关键词： solution-phase photoelectron spectroscopy 16-3-16 surfactant transmission

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Preparation of hydrogels with uniform and gradient chemical structures using dialdehyde cellulose and

Peiwen Liu, Carsten Mai, Kai Zhang

《化学科学与工程前沿（英文）》 2018年第12卷第3期页码 383-389 doi: 10.1007/s11705-018-1718-7

摘要：

Hydrogels with precisely designed structures represent promising materials with a broad application spectrum, such as for sensor, tissue engineering and biomimetic technology. However, with highly reactive compounds, the preparation of hydrogels still needs an efficient approach for desired distribution of each component within hydrogels. In addition, a method for in situ preparation of gradient hydrogels is still lacking. Herein, we report the formation of hydrogels with either uniform or gradient internal structures via a novel, simple but very efficient method by aerating ammonia gas (NH₃ gas) into the solution of dialdehyde cellulose (DAC) and a diamine. As-prepared hydrogels exhibited uniform microscopic and chemical structure or gradient distribution of functional groups. Due to lots of aldehyde groups on DAC chains, functional hydrogels can be prepared by using diverse diamines. For instance, hydrogels prepared by using 1,6-hexanediamine as a cross-linker were responsive to pH values. Moreover, this controllable process of aerating NH₃ gas allows the in situ formation of gradient hydrogels; for instance, by using cyanamide as a reaction counterpart, gradient hydrogels with gradient distributions of cyanide groups were prepared.

关键词： hydrogel uniform gradient dialdehyde cellulose ammonia gas diamine

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基于策略型消费者的易逝品最优定价研究

陈晓红,易国栋,成璐璐

《中国工程科学》 2015年第17卷第1期页码 120-128

摘要：

随着信息获取变得越来越方便快捷，消费者策略行为在日常生活中变得越来越普遍。同时，产品的易腐蚀性使得时间敏感的消费者的选择更复杂。本文研究存在策略型消费者的易腐蚀性产品最优定价问题。垄断厂商在一定时期内销售有限个产品，消费者根据效用最大化原则选择自身的最优购买时机。本文分为不补充库存和补充库存两种情形。研究表明，厂商与消费者之间存在博弈均衡，厂商公布定价策略后，存在最优的阈值函数划分消费者结构。消费者的策略行为对厂商利润有重大影响，厂商可以根据市场需求状况和消费者时间敏感程度通过适当的库存和价格设定来减少消费者策略行为带来的损失。补充库存只有在市场需求较大的时候才优于不补充库存情形。

关键词：易逝品；策略型消费者；最优定价；Stackelberg博弈

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Orderly decorated nanostructural photoelectrodes with uniform spherical TiO

A. M. Bakhshayesh,S. S. Azadfar

《化学科学与工程前沿（英文）》 2015年第9卷第4期页码 532-540 doi: 10.1007/s11705-015-1549-8

摘要： This study presents a novel nanostructural electrode made of 20-nm-diameter nanoparticles, which orderly decorated with 2-µm TiO particles, deposited by a new gel process. The decorated electrode (DE) is better than the non-decorated electrode (NE) in both light scattering and light harvesting, as confirmed by diffuse reflectance spectroscopy. X-ray diffraction reveals that both electrodes have a mixture of anatase and rutile phases. The dye-sensitized solar cell based on the decorated electrode shows the highest power conversion efficiency of 7.80% as a result of less recombination demonstrated by electrochemical impedance spectroscopy. From internal power conversion efficiency measurement, the external quantum efficiency of DE cell at 530 nm is 89%, which is higher than that of NE cell (77%).

关键词： dye-sensitized solar cell uniform particles TiO₂ gel process light harvesting

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Analytical and numerical investigation into the longitudinal vibration of uniform nanotubes

null

《机械工程前沿（英文）》 2014年第9卷第2期页码 142-149 doi: 10.1007/s11465-014-0292-z

摘要：

In recent years, prediction of the behaviors of micro and nanostructures is going to be a matter of increasing concern considering their developments and uses in various engineering fields. Since carbon nanotubes show the specific properties such as strength and special electrical behaviors, they have become the main subject in nanotechnology researches. On the grounds that the classical continuum theory cannot accurately predict the mechanical behavior of nanostructures, nonlocal elasticity theory is used to model the nanoscaled systems. In this paper, a nonlocal model for nanorods is developed, and it is used to model the carbon nanotubes with the aim of the investigating into their longitudinal vibration. Following the derivation of governing equation of nanorods and estimation of nondimensional frequencies, the effect of nonlocal parameter and the length of the nanotube on the obtained frequencies are studied. Furthermore, differential quadrature method, as a numerical solution technique, is used to study the effect of these parameters on estimated frequencies for both classical and nonlocal theories.

关键词： continuum theory differential quadrature method nanorod longitudinal vibration

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指数多项式均匀样条模型

赵颜利,平萍,刘凤玉

《中国工程科学》 2008年第10卷第7期页码 147-152

摘要：

给出了k（ k ≥ ３）阶指数多项式的均匀样条模型。该类模型具有很多与B 样条模型相同的性质，并且增加了一个可调节的形状参数。由该模型构造的曲线，通过改变形状参数的取值，可以调整曲线接近其控制多边形的程度。应用于CAD/CAM领域，可作为几何造型的一种新的有效模型。

关键词：指数多项式样条函数 B样条函数形状参数

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基于价格机制的无线网自适应接纳控制算法

张雪

《中国工程科学》 2006年第8卷第4期页码 32-38

摘要：

为了有效地控制对无线网资源的使用，针对自适应的多媒体应用带宽可以动态调整的特点以及价格对用户行为的影响，提出一种与价格机制相结合的自适应的接纳控制算法，该算法适合于无线网中具有多服务类、多优先级服务的情况，并根据网络当前状况动态地调整价格以缓解拥塞问题。该价格机制力求在有效性和易用性之间做出权衡。最后与未结合价格机制的自适应接纳控制算法进行性能对比表明，将价格机制与接纳控制结合起来，可以很大程度上改善无线网的性能。

关键词：无线网络自适应的接纳控制微观经济学价格机制连接级QoS

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Centrifugal compressor blade optimization based on uniform design and genetic algorithms

SHU Xinwei, GU Chuangang, XIAO Jun, GAO Chuang

《能源前沿（英文）》 2008年第2卷第4期页码 453-456 doi: 10.1007/s11708-008-0083-5

摘要： An optimization approach to centrifugal compressor blade design, incorporating uniform design method (UDM), computational fluid dynamics (CFD) analysis technique, regression analysis method and genetic algorithms (GA), is presented. UDM is employed to generate the geometric information of trial samples whose performance is evaluated by CFD technique. Then, function approximation of sample information is performed by regression analysis method. Finally, global optimization of the approximative function is obtained by genetic algorithms. Taking maximum isentropic efficiency as objective function, this optimization approach has been applied to the optimum design of a certain centrifugal compressor blades. The results, compared with those of the original one, show that isentropic efficiency of the optimized impeller has been improved which indicates the effectiveness of the proposed optimization approach.

关键词： information computational centrifugal compressor regression analysis CFD

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Pricing and production strategies in remanufacturing from the perspectives of supply chain: Review and

《工程管理前沿（英文）》 doi: 10.1007/s42524-023-0251-7

摘要： Remanufacturing is widely recognized as beneficial to the environment and a circular economy. However, remanufacturing is more complex than traditional manufacturing due to the effects of government policy, uncertainty of consumer preferences, competition and cooperation among firms, and so on. These factors motivate academics to optimize remanufacturing outcomes, especially for product pricing and production. This study reviews the published literature on pricing and production strategies in remanufacturing from four perspectives of supply chain, namely, government policy, consumer characteristics, relationships among firms, and supply chain structures. Review results can benefit scholars/practitioners in the future by highlighting the challenges and opportunities in remanufacturing strategies.

关键词： remanufacturing reverse and closed-loop supply chain circular economy

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Analytical solutions of three-dimensional contaminant transport in uniform flow field in porous media

Hongtao WANG, Huayong WU

《环境科学与工程前沿（英文）》 2009年第3卷第1期页码 112-128 doi: 10.1007/s11783-008-0067-z

摘要： The purpose of this study is to present a library of analytical solutions for the three-dimensional contaminant transport in uniform flow field in porous media with the first-order decay, linear sorption, and zero-order production. The library is constructed using Green's function method (GFM) in combination with available solutions. The library covers a wide range of solutions for various conditions. The aquifer can be vertically finite, semi-infinitive or infinitive, and laterally semi-infinitive or infinitive. The geometry of the sources can be of point, line, plane or volumetric body; and the source release can be continuous, instantaneous, or by following a given function over time. Dimensionless forms of the solutions are also proposed. A computer code FlowCAS is developed to calculate the solutions. Calculated results demonstrate the correctness of the presented solutions. The library is widely applicable to solve contaminant transport problems of one- or multiple- dimensions in uniform flow fields.

关键词： solution library contaminant transport analytical solution dispersion and advection porous media type curve Green's function method (GFM)