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From knowledge based software engineering to knowware based software engineering

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Science in China(Series F) 2008年第6期51卷 638-660页

作者： lu RuQian JIN zhi Academy of Mathematics and System Sciences & Institute of Computing Technology Chinese Academy ofSciences Beijing 100190 China

The first part of this paper reviews our efforts on knowledge-based software engineering, namely PROMIS, started from 1990s. The key point of PROMIS is to generate applications automatically based on domain knowledge as well as software knowledge. That is featured by separating the development of domain knowledge from the development of software. But in PROMIS, we did not find an appropriate representation for the domain knowledge. Fortunately, in our recent work, we found such a carrier for knowledge modules, i.e. knowware. Knowware is a commercialized form of domain knowledge. This paper briefly introduces the basic definitions of knowware, knowledge middleware and knowware engineering. Three life circle models of knowware engineering and the design of corresponding knowware implementations are given. Finally we discuss application system automatic generation and domain knowledge modeling on the J2EE platform, which combines the techniques of PROMIS, knowware and J2EE, and the development and deployment framework, i.e. PROMIS/KW＊＊.

关键词： PROMIS knowledge based software engineering knowware J2EE PROMIS/KW** knowware based software engineering

A novel method for road network mining from floating car data

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Geo-Spatial Information Science 2022年第2期25卷 197-211页

作者： Yuan Guo Bijun Li zhi lu Jian Zhou State Key Laboratory of Information Engineering in Surveying Mappingand Remote SensingWuhan UniversityWuhanChina

Vehicles have been increasingly equipped with GPS receivers to record their trajectories,which we call floating car *** with other data sources,these data are characterized by low cost,wide coverage,and rapid *** data have become an important source for road network *** this paper,we propose a novel approach for mining road networks from floating car ***,a Gaussian model is used to transform the data into bitmap,and the Otsu algorithm is utilized to detect road ***,a clothoid-based method is used to resample the GPS points to improve the clustering accuracy,and the data are clustered based on a distance-direction ***,road centerlines are extracted with a weighted least squares *** report on experiments that were conducted on floating car data from Wuhan,*** conclude,existing methods are compared with our method to prove that the proposed method is practical and effective.

关键词： GPS trajectory floating car data road intersection extraction data clustering

STUDY ON NEW PASSIVE SCALAR FluX MODEL WITH DIFFUSIVITY OF COMPLEX NUMBER

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维普期刊数据库

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Journal of Hydrodynamics 2000年第4期12卷 20-25页

作者： lu zhi-ming Liu Yu-lu Cai Shu-tang Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072P.R.China

The turbulent passive scalar fluxes were studied by separately considering the contributions of small eddy motions and large eddy ones. Explicit algebraic approximation was achieved for both small eddy and large eddy scalar fluxes. Especially, the large eddy scalar flux was modelled with complex diffusivity. The singular difficulties in usual algebraic scalar models, do not occur any more in this model. In addition, this new model provides a new way to reasonably describe the negative transport phenomena appearing in asymmetric turbulent flows.

关键词： turbulent passive scalar flux small eddy large eddy negative transport

The trade margins of Chinese agricultural exports to ASEAN and their determinants

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Journal of Integrative Agriculture 2018年第10期17卷 2356-2367页

作者： SUN zhi-lu LI Xian-de Institute of Agricultural Economics and Development Chinese Academy of Agricultural Sciences

How do Chinese agricultural exports to ASEAN（Association of Southeast Asian Nations） evolve？ And what factors affected the evolution pattern？ This study measures the trade margins of Chinese agricultural exports to ASEAN by utilizing the 2000-2015 Harmonized System＇s six-digit agricultural trade data, and further analyzes their determinants by developing an augmented gravity model of international trade. The results indicate that, the main growth source of Chinese agricultural exports to ASEAN has shifted from the extensive margin before the formal establishment of CAFTA（China-ASEAN Free Trade Area） in 2010 to the intensive margin since the formal establishment of CAFTA, but changes in Chinese agricultural exports to ASEAN have always mainly depended on the intensive margin. Since the formal establishment of CAFTA, the evolution pattern of Chinese agricultural exports to ASEAN has shifted from ＂more varieties, low price, and small quantity＂ to ＂less varieties, high price, and large quantity＂. Relative economic scale, relative population scale, capacity of agricultural export, trade integration, global financial crisis, and common border significantly affect the trade margins of Chinese agricultural exports to ASEAN.

关键词： China agricultural product ASEAN trade margins

New degradation call admission control for increasing WCDMA system capacity

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Journal of Systems Engineering and Electronics 2006年第4期17卷 750-754页

作者： Liu Ningqing lu zhi Gu Xuemai Dept. Electronics and Communication Engineering Harbin Inst. of Technology Harbin 150001P.R. China

Propose a new degradation call admission control（DCAC）scheme, which can be used in wideband code division multiple access communication system. So-called degradation is that non-real time call has the characteristic of variable bit rate, so decreasing its bit rate can reduce the load of the system, consequently the system can admit new call which should be blocked when the system is close to full load, therefore new call＇s access probability increases. This paper brings forward design project and does system simulation, simulation proves that DCAC can effectively decrease calls＇ blocking probability and increase the total number of the on-line users.

关键词： degradation call admission control WCDMA call block probability.

Polaronic Electron-Phonon Interactions on the Third-Harmonic Generation in a Square Quantum Well

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Communications in Theoretical Physics 2006年第1期45卷 171-174页

作者： lu zhi-En GUO Kang-Xian Department of Physics Faculty of Sciences Guihuagang Campus Guangzhou University Guangzhou 510405 China

The influence of electron-phonon interactions on third-harmonic generation in a square quantum well is investigated. The first- and third-harmonic generation coefficient is obtained by using compact-density-matrix approach and iterative method, and the numerical results are presented for a GaAs square quantum well. The results show that the third-harmonic generation coefficient is obviously enhanced after considering the influence of electron-phonon interactions.

关键词： electron-phonon interactions third-harmonic generation nonlinearity

Challenges of snow leopard conservation in China

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Science China(Life Sciences) 2016年第6期59卷 637-639页

作者： Juan Li Lingyun Xiao zhi lu Center for Nature and Society College of Life Sciences Peking University Beijing 100871 China Department of Environmental Science Policy and Management University of California Berkeley CA 94720-3114 USA Panthera New York NY 10018 USA Shanshui Conservation Center Beijing 100871 China

The snow leopard（Panthera uncial,Figure 1A）is a kind of beautiful big cat that is believed to originate on the Tibetan Plateau seven million years ago（Tseng et al.,2013）,and now inhabits alpine and subalpine zones... 详细信息

关键词： Panthera Plateau conservation mountains Russia Tibetan Figure Pakistan originate alpine

Doubly Periodic Wave Solutions of Jaulent-Miodek Equations Using Variational Iteration Method Combined with Jacobian-function Method

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Communications in Theoretical Physics 2008年第6期49卷 1403-1406页

作者： ZHU Jia-Min lu zhi-Ming LIU Yu-lu Department of Computer Yiwu Industrial and Commercial College Yiwu 322000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

One of the advantages of the variational iteration method is the free choice of initial guess. In this paper we use the basic idea of the Jacobian-function method to construct a generalized trial function with some unknown parameters. The Jaulent-Miodek equations are used to illustrate effectiveness and convenience of this method, some new explicit exact travelling wave solutions have been obtained, which include bell-type soliton solution, kink-type soliton solutions, solitary wave solutions, and doubly periodic wave solutions.

关键词： Jaulent-Miodek equations Jacobian-function method variational iteration method doubly periodic wave solution exact solution

EFFECT OF SWEEP AND EJECTION EVENTS ON PARTICLE DISPERSION IN WALL BOUNDED TURBULENT FLOWS

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Journal of Hydrodynamics 2012年第5期24卷 794-799页

作者： luO Jian-ping lu zhi-ming QIU Xiang LI Dong-mei LIU Yu-lu School of Mechanical Engineering Shanghai Institute of Technology Shanghai 200235 China Shanghai Key Laboratory of Mechanics in Energy Engineering and Shanghai Institute of Applied Mathematicsand Mechanics Shanghai University Shanghai 200072 China School of Science Shanghai Institute of Technology Shanghai 200235 China Shanghai Institute of Technology Shanghai 200235 China

This paper studies the sweep and ejection events in a channel flow with Reτ = 80 by using Direct Numerical Simulation （DNS）. The effects of ejection and sweep events on the transport of fluid particles are analyzed separately through a quadrant technique. By analyzing trajectories of the particles released at different wall-normal locations, it is found that the particles from the ejection events mainly move upward while the particles from the sweep events move downward of the flow during short and intermediate diffusion time durations. Numerical results show that the effects of the ejection and sweep events on the mean displacement and the mean square dispersion remain for a long time, one-order of magnitude larger than the streamwise Lagrangian integral ~cales.

关键词： sweep ejection dispersion quadrant analysis turbulent channel flow