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一阶分析法 1

两个市场两种资源 1

中压变频 1

低压变频 1

农产品贸易 1

合理成桥状态 1

合理电压等级 1

合理规模；多元数据；中心城区；超大特大城市；幸福感 1

合理进口规模 1

大中功率 1

岩石-炸药匹配 1

斜拉桥 1

旁路 1

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粉碎区 1

节能调速 1

钻孔爆破 1

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Aerodynamic challenges in span length of suspension bridges

XIANG Haifan, GE Yaojun

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 153-162 doi: 10.1007/s11709-007-0016-0

摘要： The potential requirement of extreme bridge spans is firstly discussed according to horizontal clearances for navigation and economical construction of deep-water foundation. To ensure the technological feasibility of suspension bridges with longer spans, the static estimation of feasible span length is then made based on current material strength and weight of cables and deck. After the performances of the countermeasures for raising the aerodynamic stability are reviewed, a trial design of a 5 000 m suspension bridge, which is estimated as a reasonable limitation of span length, is finally conducted to respond to the tomorrow s challenge in span length of suspension bridges with the particular aspects, including dynamic stiffness, aerodynamic flutter and aerostatic stability.

关键词： requirement reasonable limitation challenge particular economical construction

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Fast scaling approach based on cavitation conditions to estimate the speed limitation for axial piston

Qun CHAO, Jianfeng TAO, Junbo LEI, Xiaoliang WEI, Chengliang LIU, Yuanhang WANG, Linghui MENG

《机械工程前沿（英文）》 2021年第16卷第1期页码 176-185 doi: 10.1007/s11465-020-0616-0

摘要： The power density of axial piston pumps can benefit greatly from increased rotational speeds. However, the maximum rotational speed of axial piston machines is limited by the cavitation phenomenon for a given volumetric displacement. This paper presents a scaling law derived from an analytical cavitation model to estimate the speed limitations for the same series of axial piston pumps. The cavitation model is experimentally verified using a high-speed axial piston pump, and the scaling law is validated with open specification data in product brochures. Results show that the speed limitation is approximately proportional to the square root of the inlet pressure and inversely proportional to the cube root of volumetric displacement. Furthermore, a characteristic constant is defined based on the presented scaling law. This constant can represent the comprehensive capacity of axial piston pumps free from cavitation.

关键词： axial piston pump cavitation speed limitation scaling law

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Capacity limitation of nuclear units in grid based on analysis of frequency regulation

Yiping DAI, Pan JIANG, Lin GAO, Weimin KAN, Xiaoqing XIAO, Ge JIN

《能源前沿（英文）》 2012年第6卷第2期页码 148-154 doi: 10.1007/s11708-012-0174-1

摘要： The increasing capacity of nuclear units in power grid poses threat to system stability and security. Load disturbance may cause overspeed of the units and trigger the overspeed protection controller (OPC). Repeating actions of valves have a strong impact on the security of the equipment and may result in a collapse of the power system. Based on the analysis of frequency regulation, mathematic models for nuclear units in the grid are established in this paper to simulate the dynamic process when load disturbance occurs. The critical action of the OPC is proposed as the constraint of safe operation for the units. The relationship between different styles of frequency regulation and the allowable capacity of the nuclear units in the grid is discussed. This research can help to estimate the capacity limitation of nuclear units in the grid.

关键词： nuclear units capacity overspeed primary frequency control (PFC) second frequency control (SFC)

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大中功率节能调速传动的合理电压等级

马小亮

《中国工程科学》 2001年第3卷第11期页码 80-84

摘要：

大中功率风机和泵采用变频调速可节约大量电能，大部分功率在0.2～2 MW范围中。我国现在200 kW以上的电机多是中压，现行中压电网多为10 kV，选用10 kV直接变频从技术和经济角度看都不太合理。由于变频器输入侧都有变压器，因此电机和变频器没有必要和电网一致。文章讨论不同功率段的合理电压等级以及在电机电压和电网电压不同情况下当变频器出现故障时如何实现旁路工作。

关键词：大中功率节能调速合理电压等级低压变频中压变频旁路

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千米级斜拉桥空间非线性合理恒载索力分析

张建民,肖汝诚

《中国工程科学》 2004年第6卷第12期页码 37-42

摘要：

建立了斜拉桥索力调整的空间非线性有限元分析模型，以斜拉桥主梁和索塔的弯曲应变能为目标函数、结构应力及索力为约束条件，采用一阶最优化计算方法进行求解，用以确定成桥合理状态的索力。应用该法分析了某千米级斜拉桥的合理成桥状态，计算结果表明，该方法简单、有效。

关键词：斜拉桥一阶分析法合理成桥状态

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Genome-wide association studies: inherent limitations and future challenges

null

《医学前沿（英文）》 2012年第6卷第4期页码 444-450 doi: 10.1007/s11684-012-0225-3

摘要：

Genome-wide association studies (GWAS) have achieved great success in identifying genetic variants related to complex human diseases such as cancer and have provided valuable insights into their genetic architecture. Recently, GWAS is quite the fashion in China. However, there are issues related to its nature. Enormous work needs to be done in the post-GWAS era. Deep sequencing followed by functional studies will be needed to elucidate the underpinning biological mechanisms and further translate GWAS findings into medical practice. Along with pharmacogenomics, the success of GWAS in identifying genetic risk factors and genetic differences in drug response has been gradually enabling personalized medicine. In this article, we used hepatocellular carcinoma (HCC) as an example to demonstrate some of the inherent limitations and summarized future challenges of GWAS.

关键词： genome-wide association studies (GWAS) genetic variant cancer limitation challenge

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基于多元数据的交通视角超大特大城市中心城区合理规模研究

陆化普,柏卓彤,吴洲豪,傅志寰

《中国工程科学》 2022年第24卷第6期页码 146-153 doi: 10.15302/J-SSCAE-2022.06.013

摘要：

超大特大城市中心城区高强度连片开发、人口密度大、城市功能集中，是我国城市问题表现最为突出的区域范围；着眼集中于中心城区的大城市病破解问题，开展超大特大城市中心城区的合理规模分析论证具有迫切性。本文提出了通勤出行时间是超大特大城市中心城区合理规模的核心控制因素这一基本判断；采用大数据分析及聚类分析方法，结合城市多类土地利用的兴趣点数据、街道行政边界的地理信息系统数据，识别了我国10 个超大特大城市的现状中心城区范围；基于网络地图路径规划、手机信令数据校核，分析评价了现状交通效率；以量化分析为基础，获得了特大城市中心城区合理规模的论证结果。研究表明，当前一些超大特大城市的中心城区范围不能满足以人为本的幸福通勤出行需求；结合未来交通运输领域技术发展、治理水平提高等因素，13~15 km当量半径是超大特大城市中心城区合理规模范围的上限。

关键词：合理规模；多元数据；中心城区；超大特大城市；幸福感

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Short-term prediction of the influent quantity time series of wastewater treatment plant based on a chaos neural network model

LI Xiaodong, ZENG Guangming, HUANG Guohe, LI Jianbing, JIANG Ru

《环境科学与工程前沿（英文）》 2007年第1卷第3期页码 334-338 doi: 10.1007/s11783-007-0057-6

摘要： By predicting influent quantity, a wastewater treatment plant (WWTP) can be well controlled. The nonlinear dynamic characteristic of WWTP influent quantity time series was analyzed, with the assumption that the series was predictable. Based on this, a short-term forecasting chaos neural network model of WWTP influent quantity was built by phase space reconstruction. Reasonable forecasting results were achieved using this method.

关键词： nonlinear reconstruction WWTP influent characteristic Reasonable forecasting

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我国农产品贸易格局及合理进口规模分析

刘洋, 罗其友, 马力阳, 张晴

《中国工程科学》 2018年第20卷第5期页码 128-134 doi: 10.15302/J-SSCAE-2018.05.019

摘要：

准确分析我国农产品贸易形势，科学把握农产品进口合理规模，对贯彻落实党中央、国务院提出的农业统筹利用两个市场两种资源重大战略部署具有重要意义。本文分析了入世后我国农产品贸易总体格局的变化及驱动因素，分品种、分市场探讨了我国大宗农产品贸易的态势。以小麦、稻谷、玉米、棉花、食糖、大豆、食用植物油、猪肉、牛肉、羊肉、禽肉和水产品等重要农产品为研究对象，测算2025 年、2030 年我国农产品合理进口规模，提出了立足国内确保粮食和大宗农产品基本供给、采取积极主动的进口战略、完善国际农产品市场监测和进口预警机制、推动农业“走出去”的政策建议。

关键词：农产品贸易两个市场两种资源合理进口规模

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Experimental study for the stratified to slug flow regime transition mechanism of gas-oil two-phase flow in horizontal pipe

LIU Yiping, YANG Weilin, WANG Jing

《能源前沿（英文）》 2008年第2卷第2期页码 152-157 doi: 10.1007/s11708-008-0012-7

摘要： Theoretical relations that predict the transition from a stratified pattern to a slug pattern, including a one-dimensional wave model that contains less empiricism than the commonly used Taitel-Dukler model, and the ideal model for stratified flow for the gas-liquid flow in horizontal pipes are presented. Superficial velocities of each phase, as the onset of slugging occurs, were predicted, and theoretical analysis was conducted on the stratified to slug flow regime transition. The friction, existing between the fluid and pipe wall, and on the interface of two phases, was especially taken into account. A theoretical model was applied to an experiment about air-oil two-phase flow in a 50 mm horizontal pipe. The effect of pipe diameter on the transition was also studied. The results show that this approach gives a reasonable prediction over the whole range of flow rates, and better agreement has been achieved between predicted and measured critical parameters.

关键词： two-phase Superficial reasonable prediction one-dimensional gas-liquid

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基于粉碎区控制的钻孔爆破岩石-炸药匹配方法

冷振东,卢文波,严鹏,陈明,胡英国

《中国工程科学》 2014年第16卷第11期页码 28-35

摘要：

合理的炸药-岩石匹配关系对于提高炸药能量的有效利用率和改善破碎效果有着重要意义。传统上强调的波阻抗匹配理论并不合理，文章从爆破破碎机理出发，提出了一种岩石-炸药匹配的新方法，在保证相邻炮孔间岩石充分破碎的前提下，通过对粉碎区的合理控制来确定钻孔爆破最优的炸药性能参数。该方法可以直观地反映爆破破碎效果及能量有效利用率，可操作性强。考虑相邻炮孔爆炸荷载的联合作用，修正了钻孔爆破破坏分区计算模型。在此基础上，针对具体工程目标给出了混装炸药耦合装药条件下不同等级岩石的炸药性能匹配参数。

关键词：钻孔爆破粉碎区岩石-炸药匹配波阻抗匹配