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三峡工程 2

渤海海峡 2

跨海通道 2

5G 1

AQAM 1

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HMAC-SM3；侧信道分析；相关能量攻击；基于比特值的选择明文 1

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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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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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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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轻型高防堵性能免耕播种机研究

高焕文,李洪文,姚宗路

《中国工程科学》 2007年第9卷第9期页码 35-39

摘要：

以主动防堵的思路，提高国产免播机质量与尺寸受限情况下的防堵性能。先后研制出带状旋耕、条带粉碎和驱动圆盘3种主动防堵的轻型免播机，防堵能力强，能胜任高产玉米地免耕播种小麦，质量316~500 kg/m，与国产拖拉机匹配，价格为国外免播机1/8左右。田间对比试验表明，轻型主动防堵免播机动土量和动力消耗比国外免播机大一些，但在小麦出苗、长势和产量上优于国外机器。2006年推广近 2万台，玉米地免耕播种小麦约 40×104 hm2。

关键词：主动防堵免耕播种机轻型机具保护性耕作直接播种小麦

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Lagrangian simulation of deposition of CO gas-solid sudden expansion flow

HUANG Dongping, DING Guoliang, QUACK Hans

《能源前沿（英文）》 2008年第2卷第2期页码 216-221 doi: 10.1007/s11708-008-0032-3

摘要： Freezing and blockage resulting from the deposition of solid CO formed because of sudden expansion of the downstream pipe during the release of CO through safety valves, will endanger the protected equipment. To overcome this problem, the characteristics of the CO gas-solid sudden expansion flow are studied by using the disperse Lagrangian model. A comparison of the calculated deposition of the solid CO with the experimental results shows that they are in reasonable agreement. The simulation results show that the size of the solid CO formed should not be in the range of 0.04–0.07 mm ( number 3.2–9.8). This can be achieved by using an appropriate flow cross section of the safety valve.

关键词： comparison gas-solid downstream blockage Lagrangian

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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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Aerodynamic performance of bowed compressor cascades with different camber angles

CHEN Shaowen, CHEN Fu, WANG Keli, GU Jun, WANG Zhongqi

《能源前沿（英文）》 2008年第2卷第3期页码 306-312 doi: 10.1007/s11708-008-0056-8

摘要： The effects of a positively bowed blade on the aerodynamic performance of annular compressor cascades with different camber angles were experimentally investigated. The distributions of the exit total pressure loss and secondary flow vectors of the compressor cascades were analyzed. The static pressure was measured by tapping on the cascade surfaces, and the ink-trace flow visualizations were conducted. The results show that the value of the optimum bowed angle and optimum bowed height decrease because of the increased losses at the mid-span with the increase of the camber angle. The C-shape static pressure distribution along the radial direction exists on the suction surface of the straight cascade with larger camber angles. When bowed blade is applied, the larger bowed angle and larger bowed height will further enhance the accumulation of the low-energy fluid at the mid-span, thus causing the flow behavior to deteriorate. Under 60° camber angle, flow behavior near the end-wall region of some bowed cascades even deteriorates instead of improving because the blockage of the separated flow near the mid-span keeps the low-energy fluid near the end-walls from moving towards the mid-span region. As a result, a rapid augmentation of the total loss can easily take place under a large bowed angle.

关键词： increase different blockage increased ink-trace

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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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Blockage of receptor-interacting protein 2 expression by small interfering RNA in murine macrophages

LIU Hongchun, CAO Zhongwei, JIN Jianjun, WANG Jiyao

《医学前沿（英文）》 2008年第2卷第2期页码 166-170 doi: 10.1007/s11684-008-0030-1

摘要： This study aims to demonstrate that blocking the receptor-interacting protein2 (Rip2) expression can decrease inflammatory cytokine production by macrophage and protect mice from endotoxin lethality. Murine Rip2 small interfering RNA (siRNA) plasmids were constructed and transfected into macrophage and Rip2 expression was detected with reverse transcription-polymerase chain reaction (RT-PCR) and western blot. Cell proliferation was assayed with MTT. TNF-? concentration was assayed with ELISA and high-mobility group box 1 protein (HMGB1) level with semi-quantitative western blot after lipopolysaccharide (LPS) stimulation. LPS challenge was given after the plasmids were injected into mice and the survival rate was calculated. Rip2 siRNA plasmid could block the mRNA and protein expression of Rip2 and promote cell proliferation. Blocking Rip2 could attenuate LPS-induced TNF-? and HMGB1 production. The HMGB1 expression in the liver decreased to (40.21 ± 11.03) pg/g, and serum TNF-? level decreased to (300.43 ± 59.26) ng/L ( < 0.05). The survival rate of mice from endotoxemia was also improved ( < 0.05). The results demonstrate that Rip2 siRNA plasmid can block the expression of Rip2, decrease the production of TNF-? and HMGB1 and protect mice from fatal endotoxemia.

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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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Mechanism and control factors of hydrate plugging in multiphase liquid-rich pipeline flow systems: a review

Shuwei ZHANG, Liyan SHANG, Zhen PAN, Li ZHOU, You GUO

《能源前沿（英文）》 2022年第16卷第5期页码 747-773 doi: 10.1007/s11708-022-0830-z

摘要： There is nothing illogical in the concept that hydrates are easily formed in oil and gas pipelines owing to the low-temperature and high-pressure environment, although requiring the cooperation of flow rate, water content, gas-liquid ratio, and other specific factors. Therefore, hydrate plugging is a major concern for the hydrate slurry pipeline transportation technology. In order to further examine potential mechanisms underlying these processes, the present paper listed and analyzed the significant research efforts specializing in the mechanisms of hydrate blockages in the liquid-rich system, including oil-based, water-based, and partially dispersed systems (PD systems), in gathering and transportation pipelines. In addition, it summarized the influences of fluid flow and water content on the risk of hydrate blockage and discussed. In general, flow rate was implicated in the regulation of blockage risk through its characteristic to affect sedimentation tendencies and flow patterns. Increasing water content can potentiate the growth of hydrates and change the oil-water dispersion degree, which causes a transition from completely dispersed systems to PD systems with a higher risk of clogging. Reasons of diversity of hydrate plugging mechanism in oil-based system ought to be studied in-depth by combining the discrepancy of water content and the microscopic characteristics of hydrate particles. At present, it is increasingly necessary to expand the application of the hydrate blockage formation prediction model in order to ensure that hydrate slurry mixed transportation technology can be more maturely applied to the natural gas industry transportation field.

关键词： hydrate flow rate water content mechanism of pipeline blockage rich liquid phase system