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Demonstration of a Dynamic Braking System for Reduced Runaway Speed of Hydraulic Turbines

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Journal of Power and Energy Engineering 2017年第12期5卷 46-57页

作者： urban Lundin Johan Bladh Division of Electricity Department of Engineering Sciences Uppsala University Uppsala Sweden Vattenfall AB R & D Projects Department of Power Technology Alvkarleby Sweden

Reducing the overspeed during load rejection would benefit the mechanical and hydraulic systems in a hydropower station. This paper presents some selected results of a pilot installation of a dynamic braking system. The 4 MW dump load was installed and tested on a 10 MW Francis turbine unit. The results show that the overspeed reduction is obtained and compares well with simulation results. Further, a reduction in vibration levels is positive as well as the reduced time for stopping and possible resynchronization. It is argued that a similar system with continuous cooling could be used as an attractive alternative to spillway capacity.

关键词： Dynamic Braking Resistor Electrode Boiler Hydropower Generator Runaway Speed Water Turbine

Methods for the development and assessment of atrial fibrillation and heart failure dog models

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Journal of Geriatric Cardiology 2011年第3期8卷 133-140页

作者： Jon F urban Renee L Gerhart Jason R Krzeszak Corey R Leet Linnea R Lentz Carolyn B McClay Medtronic Inc. 710 Medtronic Parkway MS C200 Minneapolis MN 55432-5604 USA

Objective To report Medtronic experiences with the development of animal models for atrial fibrillation （AF） and chronic heart failure （CHF） using high-rate pacing for AF and microemboli for CHF. Methods For the AF model, an atrial lead was attached to a Medtronic SynergyTM neurostimulator, which was programmed to stimulate at 50 Hz in an on-off duty cycle. Atrial natfiuretic peptide （ANP）, brain natriuretic peptide （BNP） and N-terminal pro brain nalriuretic peptide （NT-proBNP） were assayed at select time points. For CHF model, a serial injection of 90 μm polystyrene microspheres at 62,400 beads/mL （Polybead, Polysciences, Inc.） was performed to induce global ischemia, either with weekly monitoring and embolization schedule （group 1, n = 25） or with biweekly monitoring and emboliation schedule （group 2, n = 36 ）. Echocardiograms were used along with ventriculograms and magnetic resonance imaging scans weekly to assess cardiac function and ANP, BNP and NT-proBNP were monitored. Results For the AF model, the days to sustained AF for four animals following surgery were 7, 25, 21 and 19, respectively; For the CHF model, the days to meet CHF endpoints were 116 in group 1 and 89 in group 2. For both AF and CHF models, NT-proBNP correlated well with the development of disease states. Conclusion Our experience for the development and assessment of AF and CHF dog models may help researchers who are in search for animal model for assessing the safety and efficacy of a device-based therapy.

关键词： atrial fibrillation congestive heart failure biological markers dog models microembolism

SOLUTION FOR THE THERMOELASTIC PROBLEM IN VERTICALLY INHOMOGENEOUS MEDIA

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Acta Mechanica Sinica 1988年第2期4卷 182-189页

作者： Yue Zhongqi, Comprehensive Institute of Geotechnical Investigation and Surveying, Ministry of urban and Rural Construction and Environmental Protection 香港大学土木工程系，Pokfulam Road HongKong China

The fundamental transient-thermoelastic problem with body forces and a heat sourcein vertically inhomogeneous media is investigated by a method presented in this paper. The basicequations in Fourier transforms and Laplace transform are obtained in the form of two sets of firstorder linear ordinary differential equations in z, Eq. (7). Furthermore, for N-layered media, thegeneral solution in the transformed spaces of the j-th layer is given for fully connected interfacebetween layers, Eq. (11). Finally, under general condition, a closed-form solution for the quasi-statictransient displacements, stresses, temperature in the body can be obtained by the convolutiontheorems for the two integral transforms. In the final solution, the Green’s functions can be expressedin terms of Hankel transforms of order zero and unity as well as inverse Laplace transform, and comeout rather neatly.

关键词： Green’s function integral transform thermoelasticity transient vertically inhomogeneous

Administrative division system changes and urbanization in China

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Journal of Geographical Sciences 1998年第4期8卷 58-65页

作者： LI Ling Centre for urban and Regional Studies, Zhongshan University, Guangzhou 510275 CHINA

s—This paper ana1yses the relationship between the administrative division system changes (ADSC) and the urbanization process in China, especially in Guangdong Province since the 1980s. It points out that there are three high tides in ADSC since the 1980s relevant to the changes of economic development. The guiding principle for ADSC is to give local government incentives by transferring more administrative powers to them and bringing along regional development by central city. This paper also discusses problems existed and future prospectives.

关键词： administrative division system urbanization China Guangdong.

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促进城市转型发展增强人民的获得感——兼论“生态修复、城市修补”工作

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城市规划 2016年第A2期40卷 7-11,18页

作者：黄艳住房和城乡建设部

我国城市的规划建设管理工作正处在一个重要的转型时期。正在全国展开的“生态修复、城市修补”工作不是通常的环境整治，而是促进城市转型发展的重要抓手，要以人民群众关心的问题为导向，要立足提高城市治理水平，做系统、综合、持续... 详细信息

我国城市的规划建设管理工作正处在一个重要的转型时期。正在全国展开的“生态修复、城市修补”工作不是通常的环境整治，而是促进城市转型发展的重要抓手，要以人民群众关心的问题为导向，要立足提高城市治理水平，做系统、综合、持续的部署。本文讨论了做好“生态修复、城市修补”的工作思路和重点内容，强调要突出生态性和惠民性、突出对城市功能的修补、突出社会和谐和社区建设、突出地方的文化特色、突出城市公共场所营造、突出基础设施的建设、突出规划建设管理的系统性，认为城市规划设计工作的转变势在必行。

关键词：生态修复城市修补城市转型发展城市治理城市规划

ECONOMIC GLOBALIZATION AND ITS IMPACTS ON urban SYSTEM IN CHINA

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Journal of Geographical Sciences 1996年第1期6卷 1-17页

作者： Xu Xueqiang Zhang Rong(Center for urban and Rogional Studies, ZhongShan University, Guangzhou 510275People’s Republic of China)Anthony Gar-on Yeh(Canter of urban Planning and Environmental Management, University of Hong Kong, Hong Kong) Ctr for urban + Regional Studies Zhongshan Univ Guangzhou 510275 China

With the implementation of economic reform and open policy, China has expanded her foreign trade, utilized a lot of foreign investment, and thethere its economy has been increasingly integrated into world economy. Because the coastal region is different in the level of socio-economic development, location and accessibility from inland region, the former has got more opporturuties of development. In the coastal region, the ekisting urban clusters are spreading and new ones are appearing. However, a large floating population, traffic jam, sprawl spread in urban land use and environmental pollution have become serious problems in coastal cities.

关键词： economic globalization urban system coastal region

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SOCIAL POLARIZATION AND SEGREGATION IN BEIJING

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Chinese Geographical Science 2001年第1期11卷 17-26页

作者： GU Chao-lin (Department of urban and Resource Sciences, Nanjing University, Nanjing 210093, P. R. China) Department of urban and Resource Sciences Nanjing University Nanjing P. R. China

The biggest change in Beijing during the last decade has been in its social structure. This transition is changing the existing situation of social "equality", and leads to polarization both in individual communities and in society as a whole. As a result, social variations and conflicting interest are growing, and some new social groups are emerging. In this paper we seek to exPlore a new urban Phenomenon in post-1984 Beijing: social polarization and segregation. At first, we will discuss *** explaining social polarization. The elements and the processes can be traced back to two main aspects of the economic reforms, namely the internal reforms unleashing a huge rural exodus and the open door policy. Special attention will be paid to the new lower end of the social ladder, which is made up largely by rural migrantsthat make up the so-called floating population. Finally we will explore how these social changes translate into urban segregation, with some consideration for future developments.

关键词： social polarization urban segregation Beijing

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Predictive value of preoperative albumin-bilirubin score and other risk factors for short-term outcomes after open pancreatoduodenectomy

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世界临床病例杂志 2023年第26期11卷 6051-6065页

作者： Hana Zavrtanik Davide Cosola David Badovinac Benjamin Hadžialjević Gašper Horvat Danaja Plevel Selene Bogoni Paola Tarchi Nicolòde Manzini ale.Tomažič Department of Abdominal Surgery University Medical Centre LjubljanaLjubljana 1000Slovenia Clinica Chirurgica Azienda Sanitaria Universitaria Giuliano IsontinaCattinara HospitalTrieste 34149Italy Department of Medical Surgical and Health SciencesUniversity of TriesteTrieste 34149Italy Faculty of Medicine University of LjubljanaLjubljana 1000Slovenia

BACKGROUND Pancreatoduodenectomy represents a complex procedure involving extensive organ resection and multiple alimentary *** is still associated with high morbidity,even in high-volume *** tools including preoperative patient-related factors to preoperatively identify patients at high risk for postoperative complications could enable tailored perioperative management and improve patient *** To evaluate the clinical significance of preoperative albumin-bilirubin score and other risk factors in relation to short-term postoperative outcomes in patients after open *** This retrospective study included all patients who underwent open pancreatic head resection(pylorus-preserving pancreatoduodenectomy or Whipple resection)for various pathologies during a five-year period(2017-2021)in a tertiary care setting at University Medical Centre Ljubljana,Slovenia and Cattinara Hospital,Trieste,***-term postoperative outcomes,namely,postoperative complications,postoperative pancreatic fistula,reoperation,and mortality,were evaluated in association with albumin-bilirubin score and other risk *** logistic regression models were built to identify risk factors associated with these short-term postoperative *** Data from 347 patients were *** complications,major postoperative complications,postoperative pancreatic fistula,reoperation,and mortality were observed in 52.7%,22.2%,23.9%,21.3%,and 5.2%of patients,*** was no statistically significant association between the albumin-bilirubin score and any of these short-term postoperative complications based on univariate *** controlling for other predictor variables in a logistic regression model,soft pancreatic texture was statistically significantly associated with postoperative complications[odds ratio(OR):2.09;95%confidence interval(95%CI):1.19-3.67];male.gender(OR:2.12;95%CI:1.15-3.93),soft pan

关键词： Pancreatoduodenectomy Albumin Bilirubin Postoperative complications Pancreatic fistula Perioperative care

“国土空间规划引领‘未来之城’”UP论坛综述

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城市规划学刊 2021年第3期 11-14页

作者： Editorial Board of urban Planning Forum 《城市规划学刊》编辑部

2021年3月19日,由同济大学建筑与城市规划学院主办,《城市规划学刊》编辑部、中国城市规划学会、《规划师》编辑部协办的2021年第1期UP (多规合一,United Planning)论坛"国土空间规划引领‘未来之城’"顺利举行。论坛采用了"网络会议+... 详细信息

2021年3月19日,由同济大学建筑与城市规划学院主办,《城市规划学刊》编辑部、中国城市规划学会、《规划师》编辑部协办的2021年第1期UP (多规合一,United Planning)论坛"国土空间规划引领‘未来之城’"顺利举行。论坛采用了"网络会议+线上直播"的形式,吸引了诸多专家学者、规划工作者和高校相关专业的师生近4万人在线参与。论坛开幕式由同济大学城市规划系主任杨贵庆教授主持,自然资源部空间规划局李枫副局长和同济大学党委副书记彭震伟教授分别致辞。李枫副局长介绍了UP论坛早期由原国土部组织举办的历史演进过程,指出此次论坛的选题主要是希望大家不要仅仅关注现在,而是要思考城市的未来演进,以及未来科技等变化趋势对城市空间演进产生的影响,进而能够从容应对。

关键词：国土空间规划城市规划设计城市规划理论空间规划体系城镇化进程未来城市城市规划学科吴志强数字规划