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A Method of Estimating Computational Complexity Based on Input Conditions for N-vehicle Problem

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Acta Mathematicae Applicatae Sinica 2010年第1期26卷 1-12页

作者： Xi xia jin-chuan Cui Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper proposes a method of estimating computational complexity of problem through analyzing its input condition for N-vehicle exploration problem. The N-vehicle problem is firstly formulated to determine the optimal replacement in the set of permutations of 1 to N. The complexity of the problem is factorial of N （input scale of problem）. To balance accuracy and efficiency of general algorithms, this paper mentions a new systematic algorithm design and discusses correspondence between complexity of problem and its input condition, other than just putting forward a uniform approximation algorithm as usual. This is a new technique for analyzing computation of NP problems. The method of corresponding is then presented. We finally carry out a simulation to verify the advantages of the method： 1） to decrease computation in enumeration; 2） to efficiently obtain computational complexity for any N-vehicle case; 3） to guide an algorithm design for any N-vehicle case according to its complexity estimated by the method.

关键词： Complexity of computation combinatorial optimization N-vehicle problem permutations inverse order

Risk assessment of water security in Haihe River Basin during drought periods based on D-S evidence theory

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Water Science and Engineering 2014年第2期7卷 119-132页

作者： Qian-jin DONG xia LIU State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Hubei Provincial Collaborative Innovation Center for Water Resources Security Wuhan University School of Geography and Planning Sun Yat-sen University

The weights of the drought risk index （DRI）, which linearly combines the reliability, resiliency, and vulnerability, are difficult to obtain due to complexities in water security during drought periods. Therefore, drought entropy was used to determine the weights of the three critical indices. Conventional simulation results regarding the risk load of water security during drought periods were often regarded as precise. However, neither the simulation process nor the DRI gives any consideration to uncertainties in drought events. Therefore, the Dempster-Shafer （D-S） evidence theory and the evidential reasoning algorithm were introduced, and the DRI values were calculated with consideration of uncertainties of the three indices. The drought entropy and evidential reasoning algorithm were used in a case study of the Haihe River Basin to assess water security risks during drought periods. The results of the new DRI values in two scenarios were compared and analyzed. It is shown that the values of the DRI in the D-S evidence algorithm increase slightly from the original results of Zhang et al. （2005）, and the results of risk assessment of water security during drought periods are reasonable according to the situation in the study area. This study can serve as a reference for further practical application and planning in the Haihe River Basin, and other relevant or similar studies.

关键词： risk assessment " water security " drought periods " entropy " D-S evidence theory "evidential reasoning algorithm " Haihe River Basin

Affinity Adsorption of Bilirubin on Cibacron Blue F3GA-modified Microporous Polytetrafluoroethylene Capillary

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Chemical Research in Chinese Universities 2010年第2期26卷 323-330页

作者： jin Gu YAO Jian-xia Department of Chemistry University of Science and Technology of China Hefei 230026 P. R. China

Bilirubin removal from human plasma was obtained via an affinity microporous polytetrafluoroethylene（MPTFE） capillary. The new adsorbent comprised grafted glycidyl methacrylate（GMA） via radiation-induced polymerization as hydrophilic coating and reactive sites; ethylenediamine（EDA） as a spacer arm; Cibacron Blue F3GA（CB F3GA） as an affinity ligand; MPTFE capillary as the supporting matrix. The average density of CB F3GA attachment to MPTFE capillaries was found to be 136.5 μmol/g. The capacity of bilirubin adsorbed on affinity MPTFE capillaries is 76.1 mg bilirubin/g polymer（at 25℃）. This new adsorbent has advantages over both membrane and traditional micro-column, and this system is stable and easy to operate. The results of blood tests suggest the CB F3GA affinity capillary has good blood compatibility.

关键词： Bilirubin removal Radiation grafting Cibacron Blue F3GA Polytetrafluoroethylene Microporous capillary

On Strong Embeddability and Finite Decomposition Complexity

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Acta Mathematica Sinica,English Series 2017年第3期33卷 403-418页

作者： Jun xia xian jin WANG College of Mathematics and Statistics Chongqing University Chongqing 401331 P. R. China

The strong embeddability is a notion of metric geometry, which is an intermediate property lying between coarse embeddability and property A. In this paper, we study the permanence properties of strong embeddability for metric spaces. We show that strong embeddability is coarsely invariant and it is closed under taking subspaces, direct products, direct limits and finite unions. Furthermore, we show that a metric space is strongly embeddable if and only if it has weak finite decomposition complexity with respect to strong embeddability.

关键词： Metric geometry strong embeddability coarse invariance permanence properties finitedecomposition complexity

RATE OF INTRA-MOLECULAR CONTACT FORMATION IN SHORT TWO-DIMENSIONAL COMPACT POLYMERS CHAINS

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Chinese Journal of Polymer Science 2006年第1期24卷 13-19页

作者： jin Chen Lin-xi Zhang A-gen xia Department of Physics Zhejiang University Hangzhou 310027 China Department of Physics Wenzhou Normal College Wenzhou 325027 China

It is important to know the rate of intra-molecular contact formation in proteins in order to understand how proteins fold clearly. Here we investigate the rate of intra-molecular contact formation in short two-dimensional compact polymer chains by calculating the probability distribution p（r） of end-to-end distance r using the enumeration calculation method and HP model on two-dimensional square lattice. The probability distribution of end-to-end distance p（r） of short two-dimensional compact polymers chains may consist of two parts, i.e. p（r） = p1（r）＋ p2（r）, where p1（r） and p2（r） are different for small r. The rate of contact formation decreases monotonically with the number of bonds N, and the rate approximately conforms to the scaling relation of k（N）∝ N^-α. Here the value of α increases with the contact radius a and it also depends on the percentage of H （hydrophobic） residues in the sequences of compact chains and the energy parameters of ^εНН、 ^εНН and ^εpp. Some comparisons of theoretical predictions with experimental results are also made. This investigation may help us to understand the protein folding.

关键词： Two-dimensional compact polymer HP model Rate of contact formation.

Joint Algorithm of Message Fragmentation and No-Wait Scheduling for Time-Sensitive Networks

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 478-490页

作者： Xi jin Changqing xia Nan Guan Peng Zeng Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016 Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China Department of Computing Hong Kong Polytechnic UniversityHong KongChina

Time-sensitive networks(TSNs)support not only traditional best-effort communications but also deterministic communications,which send each packet at a deterministic time so that the data transmissions of networked control systems can be precisely scheduled to guarantee hard real-time ***-wait scheduling is suitable for such TSNs and generates the schedules of deterministic communications with the minimal network resources so that all of the remaining resources can be used to improve the throughput of best-effort ***,due to inappropriate message fragmentation,the realtime performance of no-wait scheduling algorithms is ***,in this paper,joint algorithms of message fragmentation and no-wait scheduling are ***,a specification for the joint problem based on optimization modulo theories is proposed so that off-the-shelf solvers can be used to find optimal ***,to improve the scalability of our algorithm,the worst-case delay of messages is analyzed,and then,based on the analysis,a heuristic algorithm is proposed to construct low-delay ***,we conduct extensive test cases to evaluate our proposed *** evaluation results indicate that,compared to existing algorithms,the proposed joint algorithm improves schedulability by up to 50%.

关键词： Message fragmentation networked control system real-time scheduling time sensitive network

Stochastic stabilization of Markovian jump cloud control systems based on max-plus algebra

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Journal of Systems Engineering and Electronics 2022年第4期33卷 827-834页

作者： WANG jin YANG Hongjiu xia Yuanqing YAN Ce School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China School of Automation Beijing Institute of TechnologyBeijing 100081China

In this paper, stochastic stabilization is investigated by max-plus algebra for a Markovian jump cloud control system with a reference signal. For the Markovian jump cloud control system, there exists framework adjustment whose evolution is satisfied with a Markov chain. Using max-plus algebra, a maxplus stochastic system is used to describe the Markovian jump cloud control system. A causal feedback matrix is obtained by exponential stability analysis for a causal feedback controller of the Markovian jump cloud control system. A sufficient condition is given to ensure existence on the causal feedback matrix of the causal feedback controller. Based on the causal feedback controller, stochastic stabilization in probability is analyzed for the Markovian jump cloud control system with a reference *** results are given to show effectiveness of the causal feedback controller for the Markovian jump cloud control system.

关键词： Markovian jump cloud control system causal feedback controller max-plus algebra max-product algebra stochastic stabilization

Simultaneous measurement of velocity profile and liquid film thickness in horizontal gas–liquid slug flow by using ultrasonic Doppler method

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Chinese Journal of Chemical Engineering 2023年第6期58卷 323-340页

作者： Lusheng Zhai Bo Xu Haiyan xia Ningde jin School of Electrical and Information Engineering Tianjin UniversityTianjin 300072Chi

Horizontal gas-liquid two-phase flows widely exist in chemical engineering,oil/gas production and other important industrial *** flow pattern is the main form of horizontal gas-liquid flows and characterized by intermittent motion of film region and slug *** work aims to develop the ultrasonic Doppler method to realize the simultaneous measurement of the velocity profile and liquid film thickness of slug flow.A single-frequency single-channel transducer is adopted in the design of the field-programmable gate array based ultrasonic Doppler system.A multiple echo repetition technology is used to improve the temporal-spatial resolution for the velocity *** experiment of horizontal gas-liquid two-phase flow is implemented in an acrylic pipe with an inner diameter of 20 *** the aerated characteristics of the liquid slug,slug flow is divided into low-aerated slug flow,high-aerated slug flow and pseudo slug *** temporal-spatial velocity distributions of the three kinds of slug flows are reconstructed by using the ultrasonic velocity profile *** evolution characteristics of the average velocity profile in slug flows are investigated.A novel method is proposed to derive the liquid film thickness based on the instantaneous velocity *** liquid film thickness can be effectively measured by detecting the position and the size of the bubbles nearly below the elongated gas *** with the time of flight method,the film thickness measured by the Doppler system shows a higher accuracy as a bubble layer occurs in the film *** effect of the gas distribution on the film thickness is uncovered in three kinds of slug flows.

关键词： Gas–liquid flow Complex fluids Measurement Ultrasonic Doppler Velocity profile Liquid film thickness

The landscape and flux of a minimum network motif,Wu Xing

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Chinese Physics B 2020年第12期29卷 186-197页

作者： Kun Zhang Ashley xia jin Wang State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The U.S.Center for Chinese Medicine by Beijing University of Chinese Medicine 15005 Shady Groove RoadSuite 410RockvilleMD 20850USA Department of Chemistry and Physics Department of Applied MathematicsState University of New York at Stony BrookStony BrookNY 11794USA

Wu-Xing theory is an ancient philosophy that serves as a guiding principle in the traditional Chinese medicine(TCM).It has been used to explain the unbalance among the TCM organ systems in disease states and provide treatment philosophy *** now,it is still a challenge to explore the Wu-Xing theory beyond its philosophical *** this study,we established a quantitative framework using the landscape and flux theory to characterize the nature of the WuXing theory from a perspective of a minimal network motif and leave certain specific functional aspects of Wu-Xing theory for future *** uncovered the irregular ring shape of projection landscape for the Wu-Xing network with several local basins and *** found that the dynamics of the self-organized Wu-Xing system was determined by the underlying negative landscape gradient force and the nonequilibrium rotational *** the shape of the WuXing landscape determines the stabilities of the states,the rotational flux guarantees the persistent periodic oscillation and the stability of the *** provides a physical and quantitative basis for Yin–Yang duality of the driving forces for determining the dynamics and behaviors of the living *** landscape and flux analysis,we can identify the key parameter for the dynamics/function of Wu-Xing *** findings allow us to have a deeper understanding of the scientific merits of the ancient Wu-Xing theory from the network motif perspective.

关键词： traditional Chinese medicine nonequilibrium landscapes flux