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Reduced analysis and confirmatory research on co-adaptability theoretical solution to conflicting events in construction engineering projects

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Science China(Technological Sciences) 2010年第2期53卷 480-485页

作者： HOU XueLiang1 , LU Mei2 & WANG Kai3 1 School of Business Administration, North China Electric Power University, Beijing 102206, China 2 Department of Construction Management, Tsinghua University, Beijing 100084, China 3 College of Management, Beijing Jiaotong University, Beijing 100084, China School of Business Administration North China Electric Power University Beijing China Department of Construction Management Tsinghua University Beijing China College of Management Beijing Jiaotong University Beijing China

The co-adaptability theoretical solution to conflicting events in construction engineering projects has three problems. First, the transformation of constraint conditions of theoretical solution is very difficult in practical engineering applications; second, some coefficients are difficult to be determined; third, there are overfull circular arithmetic operations involved in it. To resolve these problems, a new method to reduce the theoretical solution complications is proposed. By analyzing the operating mechanism of theoretical solution model, redundancies in the theoretical solution can be eliminated, and the ISM mapping with the co-adaptability solution can be set up. Based on this approach, a procedure to solve practical conflicting events in construction projects is established by replacing characteristic variables with mathematic variables. The research results show that the procedure can replace the co-adaptability theoretical solution effectively and solve practical conflicting events in construction projects.

关键词： construction project conflict theoretical solution reduced analysis ISM confirmatory research

Effective point kinetic parameters calculation in Tehran research reactor using deterministic and probabilistic methods

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Nuclear Science and Techniques 2017年第12期28卷 182-192页

作者： M.Kheradmand Saadi A.Abbaspour Department of Nuclear Engineering Science and Research Branch Islamic Azad University Department of Electrical Engineering Sharif University of Technology

The exact calculation of point kinetic parameters is very important in nuclear reactor safety assessment, and most sophisticated safety codes such as RELAP5, PARCS,DYN3D, and PARET are using these parameters in their dynamic models. These parameters include effective delayed neutron fractions as well as mean generation *** parameters are adjoint-weighted, and adjoint flux is employed as a weighting function in their *** flux calculation is an easy task for most of deterministic codes, but its evaluation is cumbersome for Monte Carlo codes. However, in recent years, some sophisticated techniques have been proposed for Monte Carlo-based point kinetic parameters calculation without any need of adjoint flux. The most straightforward scheme is known as the ‘‘prompt method'' and has been used widely in literature. The main objective of this article is dedicated to point kinetic parameters calculation in Tehran research reactor(TRR) using deterministic as well as probabilistic techniques. WIMS-D5B and CITATION codes have been used in deterministic calculation of forward and adjoint fluxes in the TRR core. On the other hand, the MCNP Monte Carlo code has been employed in the ‘‘prompt method''scheme for effective delayed neutron fraction *** results have been cross-checked with probabilistic ones and validated with SAR and experimental data. In comparison with experimental results, the relativedifferences of deterministic as well as probabilistic methods are 7.6 and 3.2%, respectively. These quantities are10.7 and 6.4%, respectively, in comparison with SAR report.

关键词： Point kinetic parameters Tehran research reactor Adjoint flux Prompt method Deterministic method Probabilistic method

Status of Stratigraphy research in China

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1069-1081页

作者： YAO Jianxin BO Jingfang HOU Hongfei WANG Zejiu MA Xiulan LIU Fengshan HU Guangxiao JI Zhansheng WU Guichun WU Zhenjie LI Suping GUO Caiqing LI Ya Key Laboratory of Stratigraphy and Paleontology Ministry of Land and Resources Institute of GeologyChinese Academy of Geological Sciences Beijing 100037 China Chinese Academy of Geological Sciences Beijing 100037 China China Geological Survey Beijing 100037 China

Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy （ICS）. Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points （GSSPs） for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart （ICC）, 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for strafigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the ＂Regional Chronostratigraphic Chart of China （geologic time）＂, in which 59 stages were studied in depth. In 2014, the ＂Stratigraphic Chart of China＂ was compiled, with the essential contents as follows： the correlation between international chronostratigraphy and regional chronostratigraphy of China （geologic time）, the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage.

关键词： Stratigraphy research process status China.

Advances in Severe Convection research and Operation in China

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Journal of Meteorological research 2020年第2期34卷 189-217页

作者： Xiaoding YU Yongguang ZHENG China Meteorological Administration Training Center Beijing 100081 National Meteorological Center China Meteorological AdministrationBeijing 100081

This article reviews the advances in severe convection research and operation in China during the past several *** favorable synoptic situations for severe convective weather(SCW),the major organization modes of severe convective storms(SCSs),the favorable environmental conditions and characteristics of weather radar echoes and satellite images of SCW and SCSs,and the forecasting and nowcasting techniques of SCW,are *** a whole,Chinese scientists have achieved a profound understanding of the synoptic patterns,organization,and evolution characteristics of SCW from radar and satellite observations,and the mechanisms of different types of convective weather in ***,in-depth understanding of the multiple types of convection triggers,along with the environmental conditions,structures and organization modes,and maintenance mechanisms of supercell storms and squall lines,has been *** organization modes and climatological distributions of mesoscale convective systems and different types of SCW,and the multiscale characteristics and formation mechanisms of large hail,tornadoes,downbursts,and damaging convective wind gusts based on radar,satellite,and lightning observations,as well as the related features from damage surveys,are *** terms of operational applications,different types of identification and mesoanalysis techniques,and various forecasting and nowcasting techniques using methods such as the"ingredients-based"and deep learning algorithms,have been *** a result,the performance of operational SCW forecasts in China has been significantly improved.

关键词： severe convective weather(SCW) forecasting and nowcasting research and operation advances con temporary China

Neutronic design investigation of a liquid injection-based second shutdown system for a typical research reactor using MCNPX

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Nuclear Science and Techniques 2018年第3期29卷 51-60页

作者： Ehsan Boustani Mostafa Hassanzadeh Nuclear Science and Technology research Institute (NSTRI) Reactor and Nuclear Safety School

Safety systems, built on state-of-the-art technology, are essential for achieving acceptable levels of plant safety to minimize hazards to the reactor and the general public. The second shutdown system(SSS) as an engineered safety feature and a part of the reactor protection system(RPS) is a means for rapidly shutting down a nuclear reactor, keeping it in a subcritical state and serving as a backup to the first shutdown system(FSS). In this research, one SSS with two types of optimum chamber designs is proposed that take into account the main current characteristic features of the Tehran research reactor with improvements over earlier designs. They are based on a liquid neutron absorber injection that is preferably different, diverse, and independent from the FSS based on the rod drop mechanism. The major design characteristics of this SSS with two different chambers were investigated using MCNPX 2.6.0 code. The performed calculations showed that the designed SSS is a reliable shutdown system, assuring an appropriate shutdown margin and injection time, with no significant effects on the effective delayed neutron fraction while causing minimal variations to the core structure. Further, the reasonable financial cost and the prolongation of the operation cycle are additional advantages of this design.

关键词： Tehran research reactor Second shutdown system Nuclear safety Design criteria MCNPX code

Global Trends in Dam Removal and Related research: A Systematic Review Based on Associated Datasets and Bibliometric Analysis

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Chinese Geographical Science 2019年第1期29卷 1-12页

作者： DING Liuyong CHEN Liqiang DING Chengzhi TAO Juan Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Yunnan University Institute of International Rivers and Eco-security Yunnan University

Dam removal has been increasingly reported globally and is becoming an important approach for river management, restoration and environmental conservation in damming rivers. However, current limited knowledge of global trends in dam removal and related research may be potentially biased in terms of the geographic distribution and organisms studied. Such bias could mislead dam removal planning and management in different areas and ecological conservation for different taxa. In this study, we quantitatively and qualitatively analyzed datasets of dam removal and publications of dam removal research using bibliometric methods. A total of 1449 dam removal documents were published from 1953 to 2016. Trends, current hotspots and future directions of dam removal research were identified. The results from this study reveal that dam removal largely occurred in the North America and Europe, and most of the removed dams were small and old dams. With respect to the topic analysis, more dam removal studies should focus on the responses of a wide range of organisms, not only fish, as well as the interspecies relationships, food webs and ecosystem structures and functions. Based on our findings, we also provide some suggestions for future dam removal planning and analysis.

关键词： dam demolition literature research topics weir

Basic and translational aging research in China: present and future

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Protein & Cell 2019年第7期10卷 476-484页

作者： Xiaojuan He Moshi Song Jing Qu Yansu Guo Heqi Cao Ruijuan Sun Guang-Hui Liu Yong Shen Major Program Expert Group Advanced Innovation Center for Human Brain Protection National Clinical Research Center for Geriatric Disorders Xuanwu Hospital Capital Medical University Beijing 100053 China National Laboratory of Biomacromolecules CAS Center for Excellenee in Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Membrane Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Institute for Stem Cell and Regeneration Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Stem Cell and Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Department of Health Sciences National Natural Science Foundation of China Beijing 100085 China University of Science and Technology of China Hefei 230027 China

The percentage of elderly people in the world is increasing at an unprecedented pace;so it is in China, which has the world s largest population and a high ratio of the seniors (aged 60 and above) to working-age adults. The growing elderly population is presenting a major social challenge. Accordingly, it is not only imperative as a national strategic demand but also promises great scientific values to understand the biological process of aging, explore the mystery of healthy aging, delay the aging process, and treat the age-related diseases. This Perspective summarizes past and present advances of the basic and translational aging research in China and offers perspectives on future endeavors in this area.

关键词： aging research present future

Developments and research directions in pipe jacking and microtunneling

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Underground Space 2020年第1期5卷 1-19页

作者： Raymond L.Sterling Louisiana Tech University RustonLouisiana 71272USA

This paper provides a review of the history and development of pipe jacking and microtunneling methods with extensive referencing to the published *** application of such methods in comparison with other trenchless technologies is discussed and the various planning,design and construction aspects are *** emphasis of the paper is to trace the academic research and field monitoring results covering critical aspects of design and construction with a particular emphasis on jacking force estimation and the effect of lubrication on jacking forces.

关键词： Pipe jacking Microtunneling Design Construction research Review

The state of mountain research in Canada

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Journal of Mountain Science 2022年第10期19卷 3013-3025页

作者： Graham MCDOWELL Katherine HANLY Department of Geography University of CalgaryCalgaryABT2NiN4Canada Department of Geography University of ZurichCH-8006 ZurichSwitzerland

Nearly a quarter of Canada’s landmass is covered by mountainous terrain,making mountains an important aspect of the physical and human geography of the *** areas in Canada have motivated a great deal of research activity,yet the state of mountain research in the country has never been systematically characterized,precluding a detailed understanding of what is being studied,when,where,how,and by *** response,we conducted a systematic scoping review to rigorously identify,collate,and critically examine existing peer-reviewed articles related to mountains in Canada.2,888 articles were included in our review,which reveals strong biases towards work in the natural sciences and in the mountain west,with little work to date in the social and health sciences or in other mountainous regions of the *** results demonstrate that Canada is among the most productive contributors to mountain research globally,but that topical and geographical biases in existing research effort leave important gaps that must be addressed to successfully navigate challenges and opportunities facing mountain areas in *** provide a roadmap to guide future mountain-focused research activities in the country.

关键词： Canada Mountains Systematic scoping review research