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桥梁隧道 3

三峡工程 2

工程管理 2

渤海海峡 2

跨海通道 2

5G 1

AQAM 1

BOT 1

HMAC-SM3；侧信道分析；相关能量攻击；基于比特值的选择明文 1

OFDM 1

PPP模式 1

Q值监测 1

SIMPLEC算法 1

Z干扰信道；非正则信号；和速率；帕累托边界；协方差；伪协方差 1

丁醇 1

三维水流模型 1

上海国际航运中心 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

云计算；侧信道攻击；信息泄露；多执行体架构；虚拟机切换；虚拟机迁移 1

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Evaluation of aquatic rehabilitation technologies for polluted urban rivers and the case study of the FoshanChannel

Haifeng JIA, Nan DONG, Hongtao MA,

《环境科学与工程前沿（英文）》 2010年第4卷第2期页码 213-220 doi: 10.1007/s11783-010-0023-6

摘要： An index system for evaluation of technologies for urban river rehabilitation was proposed and discussed. The index system includes indicators of cost, resources, environmental improvement, and social effects. The calculation method for an objective value of each index based on its attributes and weights was presented. The Foshan Channel, which is a seriously polluted, black and malodorous urban river in Foshan City, China, was selected as a case study. The values of the attributes and the weights of the indices for the Foshan Channel were determined. The technologies for the rehabilitation of the Foshan Channel were evaluated based on this index system. Finally, a rehabilitation scheme for the Foshan Channel was proposed.

关键词： river rehabilitation urban rivers river pollution multi-objective analysis the Foshan Channel

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A cellphone-based colorimetric multi-channel sensor for water environmental monitoring

《环境科学与工程前沿（英文）》 2022年第16卷第12期 doi: 10.1007/s11783-022-1590-z

摘要：

● A cellphone-based colorimetric multi-channel sensor for in-field detection.

关键词： Colorimetric analysis Multi-channel sensor Cellphone Water quality indexes Environmental monitoring

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Analysis of nonlinear channel friction inverse problem

CHENG Weiping, LIU Guohua

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 205-210 doi: 10.1007/s11709-007-0024-0

摘要： Based on the Backus-Gilbert inverse theory, the singular value decomposition (SVD) for general inverse matrices and the optimization algorithm are used to solve the channel friction inverse problem. The resolution and covariance friction inverse model in matrix form is developed to examine the reliability of solutions. Theoretical analyses demonstrate that the convergence rate of the general Newton optimization algorithm is in the second-order. The Wiggins method is also incorporated into the algorithm. Using the method, noise can be suppressed effectively, and the results are close to accurate solutions with proper control parameters. Also, the numerical stability can be improved.

关键词： singular SVD second-order covariance Theoretical

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Improvement of solidification model and analysis of 3D channel blockage with MPS method

《能源前沿（英文）》 2021年第15卷第4期页码 946-958 doi: 10.1007/s11708-021-0754-z

摘要： In a severe accident of a nuclear power reactor, coolant channel blockage by solidified molten core debris may significantly influence the core degradations that follow. The moving particle semi-implicit (MPS) method is one of the Lagrangian-based particle methods for analyzing incompressible flows. In the study described in this paper, a novel solidification model for analyzing melt flowing channel blockage with the MPS method has been developed, which is suitable to attain a sufficient numerical accuracy with a reasonable calculation cost. The prompt velocity diffusion by viscosity is prioritized over the prompt velocity correction by the pressure term (for assuring incompressibility) within each time step over the “mushy zone” (between the solidus and liquidus temperature) for accurate modeling of solidification before fixing the coordinates of the completely solidified particles. To sustain the numerical accuracy and stability, the corrective matrix and particle shifting techniques have been applied to correct the discretization errors from irregular particle arrangements and to recover the regular particle arrangements, respectively. To validate the newly developed algorithm, 2-D benchmark analyses are conducted for steady-state freezing of the water in a laminar flow between two parallel plates. Furthermore, 3-D channel blockage analyses of a boiling water reactor (BWR) fuel support piece have been performed. The results show that a partial channel blockage develops from the vicinity of the speed limiter, which does not fully develop into a complete channel blockage, but still diverts the incoming melt flow that follows to the orifice region.

关键词： boiling water reactor (BWR) severe accident channel blockage moving particle semi-implicit (MPS) method solidification

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Experimental investigation of liquid metal alloy based mini-channel heat exchanger for high power electronic

Manli LUO, Jing LIU

《能源前沿（英文）》 2013年第7卷第4期页码 479-486 doi: 10.1007/s11708-013-0277-3

摘要： There is currently a growing demand for developing efficient techniques for cooling integrated electronic devices with ever increasing heat generation power. To better tackle the high-density heat dissipation difficulty within the limited space, this paper is dedicated to clarify the heat transfer behaviors of the liquid metal flowing in mini-channel exchangers with different geometric configurations. A series of comparative experiments using liquid metal alloy Ga68%In20%Sn12% as coolant were conducted under prescribed mass flow rates in three kinds of heat exchangers with varied geometric sizes. Meanwhile, numerical simulations for the heat exchangers under the same working conditions were also performed which well interpreted the experimental measurements. The simulated heat sources were all cooled down by these three heat dissipation apparatuses and the exchanger with the smallest channel width was found to have the largest mean heat transfer coefficient at all conditions due to its much larger heat transfer area. Further, the present work has also developed a correlation equation for characterizing the Nusselt number depending on Peclet number, which is applicable to the low Peclet number case with constant heat flux in the hydrodynamically developed and thermally developing region in the rectangular channel. This study is expected to provide valuable reference for designing future liquid metal based mini-channel heat exchanger.

关键词： heat exchanger liquid metal mini-channel heat dissipation heat transfer coefficient

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Effect of Joule heating on electro-osmotic flow in a closed-end micro-channel with isothermal and convective

Liang ZHAO, Linhua LIU,

《能源前沿（英文）》 2009年第3卷第4期页码 381-388 doi: 10.1007/s11708-009-0057-2

摘要： The effect of Joule heating on the steady state electro-osmotic flow in a closed-end micro-channel is studied through numerical simulation with the finite volume method. The velocity field and the temperature field are described by a rigorous mathematical model. Thermophysical properties including viscosity and thermal conductivity are considered to be temperature-dependent. The simulations show that the presence of Joule heating causes an increase in temperature and a decrease in viscosity in the whole micro-channel, which, thereafter, induce a large velocity near the wall and an increase in fluid velocity at the central region in order to maintain a zero flow rate at the cross section of the micro-channel. The effect of Joule heating on the induced pressure gradient is also studied, which is very important for the application of the closed-end micro-channel as a micro-actuator. The results reveal that the induced pressure gradient, taking into consideration Joule heating, is significantly smaller than that without considering Joule heating when the wall temperature of the micro-channel is constant. The induced pressure gradient difference between considering Joule heating and without considering Joule heating is small under the convective boundary condition.

关键词： closed-end micro-channel electrical double layer electro-osmotic flow induced pressure gradient Joule heating

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Understanding channel tropism in traditional Chinese medicine in the context of systems biology

null

《医学前沿（英文）》 2013年第7卷第3期页码 277-279 doi: 10.1007/s11684-013-0273-3

摘要：

Channel tropism is investigated and developed through long-term clinical practice. In recent years, the development of channel tropism theory has attracted increasing attention. This study analyzed channel tropism theory and the problems associated with it. Results showed that this theory and systems biology have a similar holistic viewpoint. Systems biology could provide novel insights and platform in the study of channel tropism. Some problems in channel tropism theory, including pharmacology and action mechanism, were investigated.

关键词： systems biology channel tropism theory traditional Chinese medicine application

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长江口深水航道治理工程的创新

范期锦

《中国工程科学》 2004年第6卷第12期页码 13-26

摘要：

经不断探索，依靠技术创新和严格、科学的管理，史无前例的长江口深水航道治理工程在复杂、恶劣的自然条件下取得了成功。文章论述了这一大型水运工程在设计、施工和管理方面创新的思维、作法和效果。

关键词：长江口深水航道工程管理设计施工

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Optimum design of a channel roughened by dimples to improve cooling performance

Abdus SAMAD, Ki-Don LEE, Kwang-Yong KIM, Jin-Hyuk KIM,

《能源前沿（英文）》 2010年第4卷第2期页码 262-268 doi: 10.1007/s11708-010-0012-2

摘要： Staggered arrays of dimples imprinted on opposite surfaces of an internal flow channel have been formulated numerically to enhance turbulent heat transfer compromising with pressure drop. The channel is simulated with the help of three-dimensional Reynolds-averaged Navier-Stokes (RANS) analysis. Three non-dimensional design variables based on dimple size and channel dimensions and two objectives related to heat transfer and pressure drag have been considered for shape optimization. A weighted-sum method for multi-objective optimization is applied to integrate multiple objectives into a single objective and polynomial response surface approximation (RSA) coupling with a gradient based search algorithm has been implemented as optimization technique. By the present effort, heat transfer rate is increased much higher than pressure drop and the thermal performance also has shown improvement for the optimum design as compared to the reference one. The optimum design produces lower channel height, wider dimple spacing, and deeper dimple as compared to the reference one.

关键词： Staggered three-dimensional Reynolds-averaged multi-objective optimization reference transfer

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Joint DOA and channel estimation with data detection based on 2D unitary ESPRIT in massive MIMO systems Article

Jing-ming KUANG, Yuan ZHOU, Ze-song FEI

《信息与电子工程前沿（英文）》 2017年第18卷第6期页码 841-849 doi: 10.1631/FITEE.1700025

摘要：针对大规模均匀矩形阵列提出了一种新型二维波达角和信道联合估计技术以及信号检测技术。传统波达角估计技术都建立在信道冲击响应已知的前提下，然而，在大规模天线系统中，信道估计非常具有挑战性。首先利用训练序列估计出用户与天线之间的联合信道冲击响应，然后利用该估计值基于酉ESPRIT算法获得二维角度估计，接下来可以获得不同路径的定向信道冲击响应估计。所提估计算法可以获得闭式解，避免了搜索和配对过程。与此同时，提出了一种简化的信号检测过程，该过程可以降低矩阵求逆的维度，从而降低检测复杂度。对多种情况进行了仿真验证，仿真结果证明了所提算法的有效性。

关键词：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

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西部铁路通道建设及政策措施

孙永福

《中国工程科学》 2010年第12卷第6期页码 18-24

摘要：

在分析西部铁路客货运输需求的基础上，提出目前存在的主要问题，强调了建设铁路运输通道的必要性。阐明了西部铁路网发展目标、铁路通道建设原则，以及区域通道、内部通道、国际通道等主要建设项目规划，并提出了加快西部铁路通道建设的若干政策措施。

关键词：西部铁路通道建设运输能力投融资改革铁路运价

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Experimental study on flow behavior at open channel confluences

WANG Xiekang, WANG Xianye, LU Weizhen, LIU Tonghuan

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 211-216 doi: 10.1007/s11709-007-0025-z

摘要： Channel confluences are common in natural rivers and hydraulic engineering, and the flow behavior at confluences becomes very complex because of the interaction between the tributary and the main river. In this study, the experiments were performed in a combined flume with a 30º angle between the main and tributary flume located at Sichuan University. The velocity was measured by using a three-component acoustic Doppler velocimeter (ADV) over a grid defined throughout the junction region. Based on the analysis of the velocity at the confluence, the distinctive characteristics of a channel confluence flow may be divided into several zones including a zone of separation immediately downstream of the junction branch channel, the maximum and minimum velocity regions at the upstream and downstream in the confluent channel, and a shear plane developed between the two combining flows downstream of the confluent channel. In addition, secondary circulations in different directions at the higher and lower velocity zones are observed as well.

关键词： ADV different interaction separation downstream

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Alluvial channel hydrodynamics around tandem piers with downward seepage

Rutuja CHAVAN, Wenxin HUAI, Bimlesh KUMAR

《结构与土木工程前沿（英文）》 2020年第14卷第6期页码 1445-1461 doi: 10.1007/s11709-020-0648-x

摘要： In this paper, we report the turbulent flow structures and the scour geometry around two piers with different diameters. An experiment was conducted on a non-uniform sand bed with two types of tandem arrangements, namely, pier (T1) with a 75 mm front and 90 mm rear, and pier (T2) with a 90 mm front and 75 mm rear, with and without-seepage flows, respectively. A strong wake region was observed behind the piers, but the vortex strength diminished with downward seepage. Streamwise velocity was found to be maximum near the bed downstream of the piers and at the edge of the scour hole upstream of the piers. Quadrant analysis was used to recognize the susceptible region for sediment entrainment and deposition. Upstream of the piers near the bed, the moments, turbulent kinetic energy (TKE), and TKE fluxes were found to decrease with downward seepage, in contrast to those in a plane mobile bed without piers. The reduction percentages of scour depth at the rear pier compared with the front one were approximately 40% for T1 and 60% for T2. Downward seepage also resulted in restrained growth of scouring with time.

关键词： scour seepage Strouhal number tandem arrangement turbulent characteristics

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渤海海峡跨海通道桥隧方案比选研究

宋克志

《中国工程科学》 2013年第15卷第12期页码 52-60

摘要：

从对航空及航运的影响、通行能力和行车舒适性、行车安全与气候适应性、施工难度及工程风险等方面对桥梁、隧道方案各自的技术特性进行了分析与比较。从技术角度考虑，桥隧方案皆具有实施的可行性，隧道在航运影响、气候适应性、生态环境等方面明显优于桥梁，而桥梁则在通行能力、施工难度和风险、运营成本、行车安全、行车舒适性、景观效果等方面优于隧道。随后，运用层次分析法建立了渤海海峡跨海通道比较评价的指标体系，并确定了各指标的权重系数。通过专家打分法和隶属度函数取得各定性指标和定量指标的隶属度，最后运用模糊综合评价模型计算全桥梁、全隧道及桥隧组合方案的模糊综合评价值，全隧道方案评价得分最高，因此，推荐渤海海峡跨海通道采用全隧道方案。

关键词：桥梁与隧道工程跨海通道渤海海峡方案比选模糊综合评价

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三峡工程蓄水运用后水库泥沙淤积及坝下游河道冲刷分析

卢金友,黄悦,王军

《中国工程科学》 2011年第13卷第7期页码 129-136

摘要：

根据三峡工程蓄水运用后的实测资料，简述三峡库区泥沙淤积、坝下游河道冲刷，并与论证阶段的研究成果进行对比。分析认为三峡工程蓄水运用8年，水库泥沙淤积及坝下游河道冲刷等出现的情况尚在原预测范围之内，表明原预测的研究成果可行；本次实测与预测对比，在时间上略显短促，仍需今后观测并作进一步对比；今后应加强原型观测及有关研究工作。

关键词：三峡工程试验性蓄水库区泥沙淤积坝下游河道冲刷