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气候变化 13

原位统计分布分析 3

土地利用变化 3

环境 3

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区域气候模式 2

水资源 2

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五相感应电机；电子变极；滑模控制；指数响应；转矩脉动减小 1

井壁监测 1

交流位置伺服系统 1

交流永磁同步电机；滑模控制器；扩张状态观测器；鲁棒控制；运动控制 1

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Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

《机械工程前沿（英文）》 2022年第17卷第2期 doi: 10.1007/s11465-022-0676-4

摘要： The control system presently used in shield posture rectification is based on driver experience, which is marginally reliable. The study of the related theory is flawed. Therefore, a decision-making approach for the deviation correction trajectory and posture rectification load for an earth pressure balance (EPB) shield is proposed. A calculation model of posture rectification load of an EPB shield is developed by considering the interactions among the cutter head, shield shell, and ground. The additional position change during the shield attitude correction is highlighted. The posture rectification loads and shield behaviors results can be solved by the proposed method. The influences of the stratum distribution (i.e., bedrock height in the upper-soft and lower-hard strata) on shield behaviors and posture rectification loads are analyzed. Results indicated that the increase of pitch angle in the upper-soft and lower-hard strata causes a sharp rise in vertical displacement. The bedrock height increases the magnitudes of the required posture rectification moments when h_r/D > 0.5. For a tunnel with h_r/D ≤ 0.5, the variation of h_r/D has little effect on the posture rectification moments. Finally, the posture rectifying curves based on the theoretical model are compared with the target ones based on the double circular arc interpolation method. The required results can be obtained regardless of the soil–rock compound stratum distribution. The maximum rectification moment in the rock layer is almost 12.6 times that in the soil layer. Overall, this study provides a valuable reference for moment determination and the trajectory prediction of posture rectification in compound strata.

关键词： additional position change deviation correction trajectory earth pressure balance shield mechanical model posture rectification

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Experimental and CFD analysis of nozzle position of subsonic ejector

Xilai ZHANG, Shiping JIN, Suyi HUANG, Guoqing TIAN

《能源前沿（英文）》 2009年第3卷第2期页码 167-174 doi: 10.1007/s11708-009-0001-5

摘要： The influence of nozzle position on the performance of an ejector was analyzed qualitatively with free jet flow model. Experimental investigations and computational fluid dynamics (CFD) analysis of the nozzle position of the subsonic ejector were also conducted. The results show that there is an optimum nozzle position for the ejector. The ejecting coefficient reaches its maximum when the nozzle is positioned at the optimum and decreases when deviating. Moreover, the nozzle position of an ejector is not a fixed value, but is influenced greatly by the flow parameters. Considering the complexity of the ejector, CFD is reckoned as a useful tool in the design of ejectors.

关键词： ejector nozzle position ejecting coefficient CFD

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Design and characteristics of electric supercharger for diesel engine acceleration by additional rapid

YAO Chun-de, ZHOU Hong-xiu

《机械工程前沿（英文）》 2006年第1卷第4期页码 409-412 doi: 10.1007/s11465-006-0048-5

摘要： The ES (electric supercharger) driven by a high-speed brushless motor was developed to solve the problem of smoke caused by the turbocharger s sluggish response during acceleration. Its rotation speed was from 6 000 r/min to 24 000 r/min, and the maximum flux was 0.1 kg/s. The structural design of the electric supercharger is novel, which makes it easier to set the lubricating installation and to assemble. The velocity distribution at the outlet of the electric supercharger is determined by hot-wire anemometry under various rotation speeds in steady state. Furthermore, the trends of the flux and charge rate with various speeds were analyzed. In addition, the transient response was detected from the motor setup to smooth running within 10 s, 15 s, 20 s and 25 s respectively, and the characteristic of the transient flux is under pilot study. Research results indicate that the electric supercharger can respond rapidly with the great flux, and it is independent of the operating conditions of a diesel engine. Therefore, it is a feasible way to reduce smoke emission and improve the acceleration performance.

关键词： acceleration velocity distribution high-speed brushless turbocharger electric supercharger

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Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional

Alvyn P. Berg, Ting-An Fang, Hao L. Tang

《环境科学与工程前沿（英文）》 2019年第13卷第1期 doi: 10.1007/s11783-019-1098-3

摘要：

• Swimming pool water was studied for DBPs upon exposure to additional stimulants.

• DBP formation could be induced by residual chlorine and extended incubation.

• Urine led to a massive formation of chloroform with additional stimulants.

• Reactions between chlorine and anthropogenic organics were slow and long-lasting.

• Urine control and air ventilation should be on the priority list for pool management.

关键词： Trihalomethanes Haloacetic acids Chloroform Residual chlorine Anthropogenic organics Swimming pool water

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Robust energy-efficient train speed profile optimization in a scenario-based position–time–speed network

《工程管理前沿（英文）》 2021年第8卷第4期页码 595-614 doi: 10.1007/s42524-021-0173-1

摘要： Train speed profile optimization is an efficient approach to reducing energy consumption in urban rail transit systems. Different from most existing studies that assume deterministic parameters as model inputs, this paper proposes a robust energy-efficient train speed profile optimization approach by considering the uncertainty of train modeling parameters. Specifically, we first construct a scenario-based position–time–speed (PTS) network by considering resistance parameters as discrete scenario-based random variables. Then, a percentile reliability model is proposed to generate a robust train speed profile, by which the scenario-based energy consumption is less than the model objective value at

α

confidence level. To solve the model efficiently, we present several algorithms to eliminate the infeasible nodes and arcs in the PTS network and propose a model reformulation strategy to transform the original model into an equivalent linear programming model. Lastly, on the basis of our field test data collected in Beijing metro Yizhuang line, a series of experiments are conducted to verify the effectiveness of the model and analyze the influences of parameter uncertainties on the generated train speed profile.

关键词： robust train speed profile percentile reliability model scenario-based position–time–speed network mixed-integer programming

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Strategic position and development prospects of nuclear energy in China

SHEN Wenquan

《能源前沿（英文）》 2007年第1卷第2期页码 125-128 doi: 10.1007/s11708-007-0015-9

摘要： By analyzing the challenges of China s energy supply, an excellent perspective of nuclear power development in the country has been described. Taking into account the near-, mid-, and long-term development requirements, a comprehensive, coordinated and sustainable nuclear power program is proposed. Thus, our national nuclear industry can not only catch up with the world s advanced level in proper time, but also possess enough stamina for sustainability.

关键词： development excellent perspective long-term development comprehensive national

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Air-bearing position optimization based on dynamic characteristics of ultra-precision linear stages

CHEN Xuedong, LI Zhixin

《机械工程前沿（英文）》 2008年第3卷第4期页码 400-407 doi: 10.1007/s11465-008-0060-z

摘要： Air-bearings are installed between the stator and the mover of ultra-precision linear stages to suppress vibration and mechanical contact. Spring-damping elements are used to emulate the complex interaction of the finite element model (FEM) developed in this paper and the system dynamic behaviors are analyzed. Through the experimental modal test, the validity and reliability of the model are proven. However, the dynamic characteristics including mode frequency, mode shape, and response amplitude are obviously changed with the position of air-bearings. The combined optimization method is used to optimize the air-bearings position. The best and worst positions are obtained using the dynamic characteristic analysis. The method can be generalized to the connection position of different components in manufacture elements and to implement the system dynamic characteristics optimization when the connection position can be changed.

关键词： manufacture different interaction air-bearings response amplitude

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Task-space position/attitude tracking control of FAST fine tuning system

QI Lin, ZHANG Hui, DUAN Guanghong

《机械工程前沿（英文）》 2008年第3卷第4期页码 392-399 doi: 10.1007/s11465-008-0056-8

摘要： This paper addresses the task-space position/attitude tracking control of a suspended parallel robot, which is being developed in the framework of a five-hundred meter aperture spherical radio telescope (FAST) project. Based on the quaternion algebra, a novel model-independent task-space PD controller that ensures end-effector position and attitude tracking is presented. The simulation and experimental results show that the new controller has better control effects than the traditional joint-space controller.

关键词： telescope five-hundred end-effector controller simulation

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Climate change and China’s mega urban regions

Chaolin GU, Sunsheng HAN

《结构与土木工程前沿（英文）》 2010年第4卷第4期页码 418-430 doi: 10.1007/s11709-010-0075-5

摘要： China’s mega urban regions are focal points of economic development and environmental concerns. This paper positions four mega urban regions (i.e., the Yangtze River Delta, the Pearl River Delta, the Bohai Bay Area, and the South-eastern Fujian Province) along China’s coast into the national economy and elaborates their development challenges and planning innovations. Mega urban regions in China are spatial consequences of rapid economic transition. They deserve close scrutiny and demands for innovative planning responses in order to maintain their key role in driving economic growth but limiting their greenhouse gas emission.

关键词： climate change mega urban region urban planning

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我国致密砂岩气资源潜力、分布与未来发展地位

张国生,邓松涛

《中国工程科学》 2012年第14卷第6期页码 87-93

摘要：

系统分析了我国鄂尔多斯、四川和塔里木等主要盆地致密砂岩气成藏条件和主控因素，提出斜坡岩性型和深层构造型是两种最重要的致密砂岩气藏。采用多因素叠合法预测有利含气范围，并通过对已知重点致密砂岩气田的解剖研究，刻度出储量丰度、含气面积系数等关键参数，采用类比法来计算主要盆地的致密砂岩气资源量。研究表明，我国致密砂岩气技术可采资源量为9.2万亿～13.4万亿m³，主要分布于含煤系地层的盆地中；致密砂岩气资源开发利用现实性最好，在国家政策扶持和工程技术进步的推动下，再经过10～20年的发展，有望成为我国天然气开发利用的主导资源之一。

关键词：致密砂岩气分布特征资源潜力发展地位

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Tackling climate change and promoting the energy revolution

Xiangwan DU

《能源前沿（英文）》 2018年第12卷第3期页码 338-343 doi: 10.1007/s11708-018-0535-5

摘要：

Following the Paris Agreement, green and low-carbon development has entered into a new stage. China’s international responsibility to combat climate change is consistent with the inherent sustainable development needs of the country. In this paper, the reasonability of China’s Intended Nationally Determined Contributions (INDC) is examined and the fact that low-carbon development can lead to modernization is demonstrated based on data analysis of energy economics from developed countries. Considering the fact that such an energy revolution forms the basis for China’s low-carbon transition, a roadmap of the China’s energy utilization is presented. Based on research results from the Chinese Academy of Engineering, the three historical stages of China’s energy structure reform are analyzed. Promoting a low-carbon transition through an energy revolution is a long-term and arduous process that requires a genuine transformation of development outlook and patterns. By empirically analyzing situations at home and abroad, a conclusion is made that economic development and a low-carbon transition can be achieved simultaneously; specifically, low-carbon development fosters new points of economic growth and gives rise to different development paths.

关键词： climate change Paris Agreement low-carbon transition energy revolution

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The clinicopathologic features of intraductal papillary mucinous neoplasms of the pancreas

QIN Xinyu, LIU Fenglin

《医学前沿（英文）》 2007年第1卷第2期页码 121-125 doi: 10.1007/s11684-007-0023-5

摘要： Since first described in 1982, intraductal papillary mucinous neoplasm (IPMN) has been the preferred term to describe the proliferation of the pancreatic ductal epithelium. It is totally different from pancreatic carcinoma in epi demiology, histology, pathology and prognosis. According to the site of involvement, IPMNs are classified into three categories, i.e. main duct type, branch duct type, and combined type. Most branch duct IPMNs are benign, whereas the other two types are often malignant. A large branch duct IPMN and marked dilation of the main pancreatic duct indicate the presence of adenoma at least. The additional existence of large mural nodules increases the possibility of malignancy in all types. The prognosis is more favorable after complete resection of benign and non-invasive malignant IPMNs. Malignant IPMNs that become more aggressive after parenchymal invasion necessitate adequate lymph node dissection. On the other hand, asymptomatic branch duct IPMNs without mural nodules can be observed without the need for resection for a considerable period of time. Our review addresses available data, current understanding, controversy, and future directions about IPMNs.

关键词： available additional existence necessitate intraductal papillary non-invasive

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Modified Bishop method for stability analysis of weakly sloped subgrade under centrifuge model test

《结构与土木工程前沿（英文）》 2021年第15卷第3期页码 727-741 doi: 10.1007/s11709-021-0730-z

摘要： The sliding forms of weak sloped and horizontal subgrades during the sliding process differ. In addition, the sliding form of weakly sloped subgrades exhibits considerable slippage and asymmetry. The accuracy of traditional slice methods for computing the stability safety factor of weakly sloped subgrades is insufficient for a subgrade design. In this study, a novel modified Bishop method was developed to improve the accuracy of the stability safety factor for different inclination angles. The instability mechanism of the weakly sloped subgrade was considered in the proposed method using the “influential force” and “additional force” concepts. The “additional force” reflected the weight effect of the embankment fill, whereas the “influential force” reflected the effect of the potential energy difference. Numerical simulations and experimental tests were conducted to evaluate the advantages of the proposed modified Bishop method. Compared with the traditional slice method, the error between the proposed method and the exact value is less than 32.3% in calculating the safety factor.

关键词： weakly sloped subgrade stability analysis additional force influential force modified Bishop method

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Large Scale Infrastructure Projects: The Art of Project or Change Management?

Geert Letens,Kurt Verweire,Peter De Prins

《工程管理前沿（英文）》 2016年第3卷第3期页码 197-202 doi: 10.15302/J-FEM-2016033

摘要： Although it is generally understood that change is a fundamental component of managing projects in the construction industry in general and an inevitable challenge for large scale infrastructure project in particular, there has been little to no attention in the literature to understand change in this context from a more holistic perspective. For this purpose, this work looks at change through the eyes of a framework of six batteries of change that seem essential to charge an organization’s capabilities for change. The framework brings together the expertise of four specialists that all have developed their insights over many years of study and practice, and has been validated through an extensive review of the management literature on organization development and change. Reflections on the application of this model in the construction industry and in large scale infrastructure projects demonstrate that energizing organizations to successfully deal with change goes beyond the traditional techniques of managing change from a program or project management perspective. Assessing the six batteries of change in this context can help organizations to develop capabilities for change that build change energy by balancing formal/rational methods with informal/emotional interventions at both a local (department/subproject) and global (business) level.

关键词： large scale project management organization development and change batteries of change model

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适用于混合动力汽车的表贴式永磁同步电机初始位置估算 Article

Bing TIAN,Qun-tao AN,Li SUN,Dong-yang SUN,Jian-dong DUAN

《信息与电子工程前沿（英文）》 2016年第17卷第8期页码 803-813 doi: 10.1631/FITEE.1500298

摘要：霍尔开关位置传感器初始位置测量精度为±30度，使得永磁同步电机在汽车启动阶段提供的最大电磁转矩受到限制。因此，对表贴式永磁同步电机非线性（磁饱和）模型进行了研究，并依据非线性模型进行较准确的初始位置估算。本文采用混合注入法（注入高频电压矢量和直流电压矢量）估算转子位置，其中直流电压用于改变铁芯饱和度，而铁芯饱和度又将调制高频电流响应。结合一种特殊的解调算法便可从高频电流响应中获得磁饱和特征函数以及转子位置信息。通过MATLAB/simulink和实验进行了转子位置估算。

关键词：表贴式永磁同步电机；初始位置估算；非线性模型；混合注入法；位置观测器

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标题作者时间类型操作

Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

期刊论文

Experimental and CFD analysis of nozzle position of subsonic ejector

Xilai ZHANG, Shiping JIN, Suyi HUANG, Guoqing TIAN

期刊论文

Design and characteristics of electric supercharger for diesel engine acceleration by additional rapid

YAO Chun-de, ZHOU Hong-xiu

期刊论文

Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional