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Scheduling Multi-Mode Projects under Uncertainty to Optimize Cash Flows: A Monte Carlo Ant Colony System Approach

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Journal of Computer Science & Technology 2012年第5期27卷 950-965页

作者：陈伟能张军 Department of Computer Science Sun Yat-sen UniversityGuangzhou 510006China

Project scheduling under uncertainty is a challenging field of research that has attracted increasing attention. While most existing studies only consider the single-mode project scheduling problem under uncertainty, this paper aims to deal with a more realistic model called the stochastic multi-mode resource constrained project scheduling problem with discounted cash flows （S-MRCPSPDCF）. In the model, activity durations and costs are given by random variables. The objective is to find an optimal baseline schedule so that the expected net present value （NPV） of cash flows is maximized. To solve the problem, an ant colony system （ACS） based approach is designed. The algorithm dispatches a group of ants to build baseline schedules iteratively using pheromones and an expected discounted cost （EDC） heuristic. Since it is impossible to evaluate the expected NPV directly due to the presence of random variables, the algorithm adopts the Monte Carlo （MC） simulation technique. As the ACS algorithm only uses the best-so-far solution to update pheromone values, it is found that a rough simulation with a small number of random scenarios is enough for evaluation. Thus the computational cost is reduced. Experimental results on 33 instances demonstrate the effectiveness of the proposed model and the ACS approach.

关键词： project scheduling optimization under uncertainty cash flow ant colony optimization Monte Carlo simulation

Non-negative locality-constrained vocabulary tree for finger vein image retrieval

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Frontiers of Computer Science 2019年第2期13卷 318-332页

作者： Kun SU Gongping YANG Lu YANG Peng SU Yilong YIN School of Computer Science and Technology Shandong University Jinan 250101 China School of Mechanical Electrical and Information Engineering Shandong University (Weihai)Weihai 264209 China School of Computer Science and Tech no logy Shandong University of Finance and Econo mics Jinan 250014 China School of Mathematics Dali University Dali 671000 China

Finger vein image retrieval is a biometric identification technology that has recently attracted a lot of attention. It has the potential to reduce the search space and has attracted a considerable amount of research effort recently. It is a challenging problem owing to the large number of images in biometric databases and the lack of efficient retrieval schemes. We apply a hierarchical vocabulary tree modelbased image retrieval approach because of its good scalability and high efficiency. However, there is a large accumulative quantization error in the vocabulary tree (VT) model that may degrade the retrieval precision. To solve this problem, we improve the vector quantization coding in the VT model by introducing a non-negative locality-constrained constraint: the non-negative locality-constrained vocabulary tree-based image retrieval model. The proposed method can effectively improve coding performanee and the discriminative power of local features. Extensive experiments on a large fused finger vein database demonstrate the superiority of our encoding method. Experimental results also show that our retrieval strategy achieves better performanee than other state-of-theart methods, while maintaining low time complexity.

关键词： non-negative locality-constrained vocabulary tree finger vein image retrieval large scale inverted indexing

Model analysis and experimental investigation of the friction torque during the CMP process

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Journal of Semiconductors 2011年第3期32卷 140-144页

作者：郭东明徐驰康仁科金洙吉 Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of Technology

A model for calculating friction torque during the chemical mechanical polishing（CMP） process is presented,and the friction force and torque detection experiments during the CMP process are carried out to verify the *** results show that the model can well describe the feature of friction torque during CMP processing. The research results provide a theoretical foundation for the CMP endpoint detection method based on the change of the torque of the polishing head rotational spindle.

关键词： CMP friction torque endpoint detection

Audio-visual emotion recognition with multilayer boosted HMM

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Journal of Beijing Institute of Technology 2013年第1期22卷 89-93页

作者：吕坤贾云得张欣 School of Software Beijing Institute of Technology Beijing Lab of Intelligent Information Technology School of Computer ScienceBeijing Institute of Technology

Emotion recognition has become an important task of modern human-computer interac- tion. A multilayer boosted HMM （ MBHMM ） classifier for automatic audio-visual emotion recognition is presented in this paper. A modified Baum-Welch algorithm is proposed for component HMM learn- ing and adaptive boosting （AdaBoost） is used to train ensemble classifiers for different layers （cues）. Except for the first layer, the initial weights of training samples in current layer are decided by recognition results of the ensemble classifier in the upper layer. Thus the training procedure using current cue can focus more on the difficult samples according to the previous cue. Our MBHMM clas- sifier is combined by these ensemble classifiers and takes advantage of the complementary informa- tion from multiple cues and modalities. Experimental results on audio-visual emotion data collected in Wizard of Oz scenarios and labeled under two types of emotion category sets demonstrate that our approach is effective and promising.

关键词： emotion recognition audio-visual fusion Baum-Welch algorithm multilayer boostedHMM Wizard of Oz scenario

Two new diterpenoid lactones isolated from Andrographis paniculata

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Chinese Journal of Natural Medicines 2017年第6期15卷 458-462页

作者： WANG Gui-Yang WEN Ting LIU Fei-Fei TIAN Hai-Yan FAN Chun-Lin HUANG Xiao-Jun YE Wen-Cai WANG Ying Institute of Traditional Chinese Medicine & Natural Products College of pharmacy Jinan University Guangzhou 510632China JNU-HKUSTjoint Laboratory for Neuroscience & Innovative Drug Research College of Pharmacy Jinan University Guang-zhou 510632 China

In the present study, two new diterpenoid lactones, 3-deoxy-andrographoside(1) and 14-deoxy-15-methoxy-andrographolide(2), were isolated from the aerial parts of Andrographis paniculata. Their structures were elucidated by combination of NMR, MS, and chemical methods. The configurations of 1 and 2 were established based on the analysis of ROESY data and single crystal X-ray diffraction experiment.

关键词： Acanthaceae Andrographis paniculata Diterpenoid lactones

High-Speed Machining of Malleable Cast Iron by Various Cutting Tools Coated by Physical Vapor Deposition

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 299-316页

作者： Suyang Li Haisheng Lin Tingjie Zhang Jianbo Sui Chengyong Wang School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Wenshan Business Information Management School Wenshan 530004China

The coating material of a tool directly affects the efficiency and cost of machining malleable cast ***,the machining adaptability of various coating materials to malleable cast iron has been insufficiently *** this paper,turning tests were conducted on cemented carbide tools with different coatings(a thick TiN/TiAlN coating,a thin TiN/TiAlN coating,and a nanocomposite(nc)TiAlSiN coating).All coatings were applied by physical vapor *** a comparative study of chip morphology,cutting force,cutting temperature,specific cutting energy,tool wear,and surface roughness,this study analyzed the cutting characteristics of the tools coated with various materials,and established the relationship between the cutting parameters and machining *** results showed that in malleable cast iron machining,the coating material significantly affects the cutting performance of the *** the three tools,the nc-TiAlSiN-coated carbide tool achieved the minimum cutting force,the lowest cutting temperature,least tool wear,longest tool life,and best surface ***,in comparisons between cemented-carbide and compacted-graphite cast iron machined under the same conditions,the wear mechanism of the coated tools was found to depend on the cast iron being ***,the performance requirements of a tool depend on multiple factors,and selecting an appropriately coated tool for a particular cast iron material is essential.

关键词： Malleable cast iron Tool-workpiece matching Cemented carbide coated tool PVD coating Dry turning

First-principles investigation of the concentration effect on equilibrium fractionation of Ca isotopes in forsterite

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Acta Geochimica 2019年第4期38卷 497-507页

作者： Yahui Song Yonghui Li Wenzhong Wang Zhongqing Wu Laboratory of Seismology and Physics of Earth’s Interior School of Earth and Space Sciences University of Science and Technology of China

Previous theoretical studies have found that the concentration variations within a certain range have a prominent effect on inter-mineral equilibrium isotope fractionation(10^3 lna).Based on the density functional theory,we investigated how the average Ca–O bond length and the reduced partition function ratios(10^3 lnb)and103lna of 44 Ca/40 Ca in forsterite(Fo)are affected by its Ca *** results show that Ca–O bond length in forsterite ranges from 2.327 to 2.267 A with the Ca/(Ca+Mg)varying between a narrow range limited by an upper limit of 1/8 and a lower limit of 1/***,outside this narrow range,i.e.,Ca/(Ca+Mg)is lower than1/64 or higher than 1/8,Ca–O bond length becomes insensitive to Ca concentration and maintains to be a *** the 10^3 lnb is negatively correlated with Ca–O bond length,the 10^3lnb significantly increases with decreasing Ca/(Ca+Mg)when 1/64

关键词： Ca isotope First-principles calculations Forsterite Concentration effect Equilibrium isotope fractionation

Tuning of interactions between cathode and lithium polysulfide in Li-S battery by rational halogenation

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Journal of Energy Chemistry 2020年第10期29卷 147-152页

作者： Samson O.Olanrele Zan Lian Chaowei Si Shuo Chen Bo Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry(Ministry of Education of China) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Chemical Sciences Department Mountain Top UniversityOgun StateNigeria

Li-S batteries have aroused intense interests as one of the most promising high-energy-density storage ***,the complex undesired shuttle effect induced by dissolution and diffusion of lithium polysulfide intermediates remains the major setback of this *** modification of carbon cathode through heteroatom-doping is widely accepted as an effective method to inhibit the shuttle effect in Li-S battery ***,using first principle calculations,we systematically examined the interaction between halogenated graphene and lithium polysulfide *** is found that the halogen dopants(F,Cl,Br,I)significantly modify the local electronic structure of adsorption site and further induce a polarization to trap the ***,a concave curve is observed from F to I for lithium polysulfide adsorption rather than a linear *** exceptions demonstrated from iodine dopant is carefully analyzed and attributed to its unique charge ***,boron as second dopant further strengthens the interaction between halogenated graphene and polysulfide *** on halogenation strategy,lithium polysulfide/cathode interactions are tuned in a wide range,which can also be of great importance to accelerate redox reaction in Li-S ***,an effective method by halogenation is verified to regulate the adsorption of lithium polysulfide and also enhance the reaction kinetics of the Li-S battery system.

关键词： Li-S battery Halogenation Shuttle effect Co-doping

Cuckoo search with varied scaling factor

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Frontiers of Computer Science 2015年第4期9卷 623-635页

作者： Lijin WANG Yilong YIN Yiwen ZHONG School of Computer Science and Technology Shandong University Jinan 250101 China College of Computer and Information Science Fujian Agriculture and Forestry University Fuzhou 350002 China School of Computer Science and Technology Shandong University of Finance and Economics Jinan 250014 China

Cuckoo search （CS）, inspired by the obligate brood parasitic behavior of some cuckoo species, iteratively uses L6vy flights random walk （LFRW） and biased/selective random walk （BSRW） to search for new solutions. In this study, we seek a simple strategy to set the scaling factor in LFRW, which can vary the scaling factor to achieve better performance. However, choosing the best scaling factor for each problem is intractable. Thus, we propose a varied scal- ing factor （VSF） strategy that samples a value from the range [0,1] uniformly at random for each iteration. In addition, we integrate the VSF strategy into several advanced CS vari- ants. Extensive experiments are conducted on three groups of benchmark functions including 18 common test functions, 25 functions proposed in CEC 2005, and 28 functions intro- duced in CEC 2013. Experimental results demonstrate the ef- fectiveness of the VSF strategy.

关键词： cuckoo search algorithm uniform distribution,random sampling scaling factor function optimization prob-lems