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Heuristic for no-wait flow shops with makespan minimization based on total idle-time increments

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Science in china(Series F) 2008年第7期51卷 896-909页

作者： LI XiaoPing1,2 & WU Cheng3 1 School of computer Science & Engineering, Southeast university, Nanjing 210096, china 2 Key Laboratory of computer Network and Information Integration (Southeast university), Ministry of Education, Nanjing 210096, china 3 department of Automation, Tsinghua university, Beijing 100084, china School of computer Science & Engineering Southeast University Nanjing China Key Laboratory of computer Network and Information Integration (Southeast university) Ministry of Education Nanjing China department of Automation Tsinghua University Beijing China

No-wait flow shops with makespan minimization are classified as NP-hard. In this paper, the optimization objective is equivalently transformed to total idle-time minimization. The independence relationship between tasks is analyzed, and objective increment properties are established for the fundamental operators of the heuristics. The quality of the new schedules generated during a heuristic is judged only by objective increments and not by the traditional method, which computes and compares the objective of a whole schedule. Based on objective increments, the time complexity of the heuristic can be decreased by one order. A seed phase is presented to generate an initial solution according to the transformed objective. Construction and improvement phases are introduced by experimental analysis. The FCH （fast composite heuristic） is proposed and compared with the most effective algorithms currently available for the considered problem. Experimental results show that the effectiveness of the FCH is similar to that of the best methods but requires far less computation time. The FCH can also be efficient in real time scheduling and rescheduling for no-wait flow shops.

关键词： no-wait flow shops heuristic makespan Tabu search

Superconductivity of small metal grains

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2 & ZHU Shunquan1,3 1. department of Physics, Shanghai Normal university, Shanghai 200234, china 2. department of Physics, Southwest Normal university, Chongqing 400715, china 3. department of computer and Electric Technology, Shanghai Business School, Shanghai 201400, china department of Physics Shanghai Normal University Shanghai China department of Physics Southwest Normal University Chongqing China department of computer and Electric Technology Shanghai Business School Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Seamlet carving for shape-aware image resizing

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Science china(Information Sciences) 2012年第5期55卷 1073-1081页

作者： LIN Xiao 1,2,SHENG Bin 1,MA LiZhuang 1,SHEN Yang 1 & CHEN ZhiHua 3 1 department of computer Science and Engineering,Shanghai Jiao Tong university,Shanghai 200240,china 2 Academy of Information Technology,Luoyang Normal university,Luoyang 471022,china 3 department of computer Science and Engineering,East china university of Science and Technology,Shanghai 200237,china department of computer Science and Engineering Shanghai Jiao Tong University Shanghai China Academy of Information Technology Luoyang Normal University Luoyang China department of computer Science and Engineering East China University of Science and Technology Shanghai China

In this paper we propose an optimized seam-carving approach for anti-shearing image *** image/video seam-carving strategy only focuses on deleting the pixels along 8-connected seams,which may lead to the obvious information loss during *** the traditional seam-carving methods,our approach can construct a seamlet to handle the discontinuous pixels and further achieve an optimized image resizing results with *** particular,to suppress zigzag artifacts,we introduce the anti-shearing energy into the seamlet generation,which includes two steps:1) the energy map is formalized by using Gabor filtering and the saliency map;2) The energy computation is optimized in Gabor feature space to obtain the resizing results without the connectivity *** experimental results and comparisons show the effectiveness of our method.

关键词： image resizing seamlet carving saliency map

EXACT EXPLICIT SOLUTIONS OF THE NONLINEAR SCHRDINGER EQUATION COUPLED TO THE BOUSSINESQ EQUATION

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Acta Mathematica Scientia 2003年第4期23卷 453-460页

作者：姚若侠李志斌 department of computer Science Weinan Teachers' College Weinan 714000 China department of computer Science East China Normal University Shanghai 200062 China

A system comprised of the nonlinear Schrodinger equation coupled to the Boussinesq equation (S-B equations) which dealing with the stationary propagation of coupled non-linear upper-hybrid and magnetosonic waves in magnetized plasma is proposed. To examine its solitary wave solutions, a reduced set of ordinary differential equations are considered by a simple traveling wave transformation. It is then shown that several new solutions (either functional or parametrical) can be obtained systematically, in addition to rederiving all known ones by means of our simple and direct algebra method with the help of the computer algebra system Maple.

关键词： Coupled Schrodinger-Boussinesq equations traveling wave transformation Riccati equations solitary wave solution

Image stylization with enhanced structure on GPU

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Science china(Information Sciences) 2012年第5期55卷 1093-1105页

作者： LI Ping 1,SUN HanQiu 1,SHENG Bin 1,2 & SHEN JianBing 3 1 department of computer Science and Engineering,The Chinese university of Hong Kong,Hong Kong,china 2 department of computer Science and Engineering,Shanghai Jiao Tong university,Shanghai 200240,china 3 School of computer Science and Technology,Beijing Institute of Technology,Beijing 100081,china department of computer Science and Engineering The Chinese University of Hong Kong Hong Kong China department of computer Science and Engineering Shanghai Jiao Tong University Shanghai China School of computer Science and Technology Beijing Institute of Technology Beijing China

This paper presents a graphics processing unit (GPU) based stylization approach that preserves the fine structure between the original and the stylized images using gradient *** abstraction and painterly stylization methods focused on contrast manipulation only,and thus the detailed salient structures of the input images are always destroyed when performing the current stylization techniques because of limitations like unavoidable salience information loss caused by contrast *** propose an image structure map to naturally model the fine structure existing in the original ***-based structure tangent generation and tangent-guided image morphology are used to construct the structure *** image structure map,unlike an edge map,not only systematically models the boundary information within the imagery but also accentuates the underlying inner structure detail for further *** facilitate the final stylization via parallel bilateral grid and structure-aware stylizing optimization on a GPU-CUDA platform in real *** multiple experiments,the proposed method consistently demonstrates efficient and high quality image stylization performance.

关键词： image stylization non-photorealistic rendering real-time processing GPU image abstraction

A user-space file system for on-demand legacy desktop software

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Science china(Information Sciences) 2011年第6期54卷 1142-1150页

作者： ZHANG YouHui 1,2 , SU GeLin 1,2 & ZHENG WeiMin 1,2 1 department of computer Science and Technology, Tsinghua university, Beijing 100084, china 2 Tsinghua National Laboratory for Information Science and Technology, Tsinghua university, Beijing 100084, china department of computer Science and Technology Tsinghua University Beijing China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing China

Some user-level virtualization technologies have been used to convert legacy software (like the existing Windows desktop applications) into the on-demand software without any modification. To give the client a friendly and compatible method to access on-demand legacy software across the Internet, this paper presents a clientend file system for this usage case. It is a Windows user-space file system based on the cloud storage (where the on-demand software is stored), which converts the local file system accesses into remote visits. Quite a few optimizations are adopted and adjusted to suit the file-access-pattern of on-demand software, including the local cache, metadata/data/software prefetch and content-addressable storage (CAS), to decrease the number of remote visits and/or to overlap IO (input/output) operations with software execution. Detailed access-pattern analyses are also presented. This file system has been implemented and tests show that it is practical for much daily-used software-a local cache of limited size can provide up to 80% hit ratio and the corresponding overhead of running-time is about 37%. Owing to this method, on any compatible and networked computer, a user can use his/her personalized software conveniently although it does not exist on the local host.

关键词： on-demand software software as a service user-space file system cloud storage

The electric properties and the current-controlled differential negative resistance of cBN crystal

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Science china(Technological Sciences) 2008年第12期51卷 2295-2300页

作者： DOU QingPing1 & MA HaiTao2 1 department of computer,Zhuhai College of Jinan university,Zhuhai 519070,china 2 Institute No.25 of the Second Academy,china Aerospace Science & Industry Corp,Beijing,100854,china department of computer Zhuhai College of Jinan University Zhuhai China Institute No.25 of the Second Academy China Aerospace Science & Industry Corp Beijing China

The electric properties of nonintentionally doped n-cubic boron nitride(cBN) crystal are *** cBN crystal was transformed from hexagonal-boron nitride(h-BN) under high pressure(HP) and high temperature(HT) using magnesium powder as *** room temperature,the current-voltage(I-V) characteristics of cBN crystal are measured and found to be *** the electric field is in the range of(1―1.5)×105 V/cm,the avalanche breakdown occurs inside the whole cBN *** this same time,the bright blue-violet with the wavelength of 380―400 nm from the cBN crystal is *** measuring the I-V curve after breakdown of cBN crystal,the current-controlled differential negative resistance phenomenon is *** breakdown is repeatable.

关键词： nonintentionally doped n-cBN nonlinear I-V characteristics current-controlled differential negative resistance light emission

Ambient electrosynthesis of urea from carbon dioxide and nitrate over Mo_(2)C nanosheet

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Chinese Chemical Letters 2024年第8期35卷 319-323页

作者： Yue Zhang Xiaoya Fan Xun He Tingyu Yan Yongchao Yao Dongdong Zheng Jingxiang Zhao qinghai Cai Qian Liu Luming Li Wei Chu Shengjun Sun Xuping Sun College of Chemistry and Chemical Engineering and Key Laboratory of Photonic and Electronic Bandgap MaterialsMinistry of EducationHarbin Normal UniversityHarbin 150025China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Institute for Advanced Study Chengdu UniversityChengdu 610106China College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJi’nan 250014China

Electrocatalytic synthesis of urea through C-N bond formation,converting carbon dioxide(CO_(2))and ni-trate(NO_(3)^(-)),presents a promising,less energy-intensive alternative to industrial urea production *** this communication,we report the application of Mo_(2)C nanosheets-decorated carbon sheets(Mo_(2)C/C)as a highly efficient electrocatalyst for facilitating C-N coupling in ambient urea *** CO_(2)-saturated 0.2 mol/L Na_(2)SO_(4)solution containing 0.05 mol/L NO_(3)^(-),the Mo_(2)C/C catalyst achieves an impres-sive urea yield of 579.13μg h^(-1)mg^(-1)with high Faradaic efficiency of 44.80%at-0.5 V versus the reversible hydrogen *** theoretical calculations reveal that the multiple Mo active sites enhance the formation of^(∗)CO and^(∗)NH_(2)intermediates and facilitate their C-N *** research propels the use of Mo_(2)C-based electrodes in electrocatalysis and accentuates the capabilities of binary metal-based catalysts in C-N coupling reactions.

关键词： Mo_(2)C Multiple active sites C-N coupling Electrocatalysis Urea synthesis Density functional theory calculation

Computational model for perception of objects and motions

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Science china(Life Sciences) 2008年第6期51卷 526-536页

作者： YANG WenLu1,2, ZHANG LiQing1 & MA LiBo1 1 department of computer Science and Engineering, Shanghai Jiao Tong university, Shanghai 200240, china 2 department of Electronic Engineering, Shanghai Maritime university, Shanghai 200135, china department of computer Science and Engineering Shanghai Jiao Tong University Shanghai China department of Electronic Engineering Shanghai Maritime University Shanghai China

Perception of objects and motions in the visual scene is one of the basic problems in the visual system. There exist 'What' and 'Where' pathways in the superior visual cortex, starting from the simple cells in the primary visual cortex. The former is able to perceive objects such as forms, color, and texture, and the latter perceives 'where', for example, velocity and direction of spatial movement of objects. This paper explores brain-like computational architectures of visual information processing. We propose a visual perceptual model and computational mechanism for training the perceptual model. The compu- tational model is a three-layer network. The first layer is the input layer which is used to receive the stimuli from natural environments. The second layer is designed for representing the internal neural information. The connections between the first layer and the second layer, called the receptive fields of neurons, are self-adaptively learned based on principle of sparse neural representation. To this end, we introduce Kullback-Leibler divergence as the measure of independence between neural responses and derive the learning algorithm based on minimizing the cost function. The proposed algorithm is applied to train the basis functions, namely receptive fields, which are localized, oriented, and bandpassed. The resultant receptive fields of neurons in the second layer have the characteristics resembling that of simple cells in the primary visual cortex. Based on these basis functions, we further construct the third layer for perception of what and where in the superior visual cortex. The proposed model is able to perceive objects and their motions with a high accuracy and strong robustness against additive noise. computer simulation results in the final section show the feasibility of the proposed perceptual model and high efficiency of the learning algorithm.

关键词： visual perception visual cortex computational model receptive fields simple cells complex cells