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Fuzzy multiple attribute decision-making model for synergic knowledge innovation in supply chain
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作者 吴冰 赵林度 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期46-50,共5页
The procedure of supply chain development is the process of continuously congregating knowledge and transforming knowledge.First,the precondition of synergic knowledge innovation in the supply chain is narrated.Then t... The procedure of supply chain development is the process of continuously congregating knowledge and transforming knowledge.First,the precondition of synergic knowledge innovation in the supply chain is narrated.Then the characteristics of synergic knowledge innovation in the supply chain are analyzed,including complexity,accumulating and evolving process,and the cooperation of members and network integration.Due to the characteristics of multi-factors and uncertainties of the supply chain system,the fuzzy multi-attribution group decision-making model is introduced to solve the involved problem of synergic knowledge innovation in the supply chain.After elaborating on steps of using the fuzzy multiple attribute decision-making(MADM)model,the procedure of decision making for synergic knowledge innovation in the supply chain is explained from an example in the application of a fuzzy MADM model.The fuzzy MADM model,which amalgamates intuition and resolution decision-making can effectively improve the rationality of decision-making for synergic knowledge innovation in the supply chain. 展开更多
关键词 synergic knowledge innovation supply chain fuzzy multiple attribute decision-making
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Air combat decision-making of multiple UCAVs based on constraint strategy games 被引量:12
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作者 Shou-yi Li Mou Chen +1 位作者 Yu-hui Wang Qing-xian Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第3期368-383,共16页
Game theory can be applied to the air combat decision-making problem of multiple unmanned combat air vehicles(UCAVs).However,it is difficult to have satisfactory decision-making results completely relying on air comba... Game theory can be applied to the air combat decision-making problem of multiple unmanned combat air vehicles(UCAVs).However,it is difficult to have satisfactory decision-making results completely relying on air combat situation information,because there is a lot of time-sensitive information in a complex air combat environment.In this paper,a constraint strategy game approach is developed to generate intelligent decision-making for multiple UCAVs in complex air combat environment with air combat situation information and time-sensitive information.Initially,a constraint strategy game is employed to model attack-defense decision-making problem in complex air combat environment.Then,an algorithm is proposed for solving the constraint strategy game based on linear programming and linear inequality(CSG-LL).Finally,an example is given to illustrate the effectiveness of the proposed approach. 展开更多
关键词 Game theory Time-sensitive information Constraint strategy games Polytope strategy games multiple UCAVs Air combat decision-making
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DNA extraction method selection for agricultural soil using TOPSIS multiple criteria decision-making model 被引量:1
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作者 Sepideh Pakpour Snizhana V. Olishevska +2 位作者 Shiv O. Prasher Abbas S. Milani Martin R. Chénier 《American Journal of Molecular Biology》 2013年第4期215-228,共14页
There is an increased interest in the extraction of nucleic acids from various environmental samples since culture-independent molecular techniques contribute to deepen and broaden the understanding of a greater porti... There is an increased interest in the extraction of nucleic acids from various environmental samples since culture-independent molecular techniques contribute to deepen and broaden the understanding of a greater portion of uncultivable microorganisms. Due to difficulties to select the optimum DNA extraction method in view of downstream molecular analyses, this article presents a straightforward mathematical framework for comparing some of the most commonly used methods. Four commercial DNA extraction kits and two physical-chemical methods (bead-beating and freeze-thaw) were compared for the extraction of DNA under several quantitative DNA analysis criteria: yield of extraction, purity of extracted DNA (A260/280 and A260/230 ratios), degradation degree of DNA, easiness of PCR amplification, duration of extraction, and cost per extraction. From a practical point of view, it is unlikely that a single DNA extraction strategy can be optimum for all selected criteria. Hence, a systematic Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was employed to compare the methods. The PowerSoil? DNA Isolation Kit was systematically defined as the best performing method for extracting DNA from soil samples. More specifically, for soil:manure and soil:manure:biochar mixtures, the PowerSoil?DNA Isolation Kit method performed best, while for neat soil samples its alternative version gained the first rank. 展开更多
关键词 DNA Extraction Agricultural Soil BIOCHAR POULTRY MANURE multiple Criteria decision-making Technique for Order PREFERENCE by Similarity to IDEAL Solution
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Cotangent Similarity Measure of Consistent Neutrosophic Sets and Application to Multiple Attribute Decision-Making Problems in Neutrosophic Multi-Valued Setting
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作者 Angyan Tu Jiancheng Chen Bing Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第11期377-387,共11页
A neutrosophic multi-valued set(NMVS)is a crucial representation for true,false,and indeterminate multivalued information.Then,a consistent single-valued neutrosophic set(CSVNS)can effectively reflect the mean and con... A neutrosophic multi-valued set(NMVS)is a crucial representation for true,false,and indeterminate multivalued information.Then,a consistent single-valued neutrosophic set(CSVNS)can effectively reflect the mean and consistency degree of true,false,and indeterminate multi-valued sequences and solve the operational issues between different multi-valued sequence lengths in NMVS.However,there has been no research on consistent single-valued neutrosophic similarity measures in the existing literature.This paper proposes cotangent similarity measures and weighted cotangent similarity measures between CSVNSs based on cotangent function in the neutrosophic multi-valued setting.The cosine similarity measures showthe cosine of the angle between two vectors projected into amultidimensional space,rather than their distance.The cotangent similaritymeasures in this study can alleviate several shortcomings of cosine similarity measures in vector space to a certain extent.Then,a decisionmaking approach is presented in viewof the established cotangent similarity measures in the case of NMVSs.Finally,the developed decision-making approach is applied to selection problems of potential cars.The proposed approach has obtained two different results,which have the same sort sequence as the compared literature.The decision results prove its validity and effectiveness.Meantime,it also provides a new manner for neutrosophic multi-valued decision-making issues. 展开更多
关键词 Neutrosophic multi-valued set consistency single-valued neutrosophic sets cotangent similarity measure multiple attribute decision-making
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ON THE EXISTENCE OF PERIODIC SOLUTIONS FOR NONLINEAR SYSTEM WITH MULTIPLE DELAYS 被引量:6
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作者 曹显兵 《应用数学和力学》 CSCD 北大核心 2003年第1期105-110,共6页
The existence of T_periodic solutions of the nonlinear system with multiple delays is studied. By using the topological degree method, sufficient conditions are obtained for the existence of T_periodic solutions. As a... The existence of T_periodic solutions of the nonlinear system with multiple delays is studied. By using the topological degree method, sufficient conditions are obtained for the existence of T_periodic solutions. As an application, the existence of positive periodic solution for a logarithmic population model is established under some conditions. 展开更多
关键词 多滞量 周期解 拓扑度 周期扰动非线性系统 单种群对数模型
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Multiple Periodic Solutions for Some Classes of First-Order Hamiltonian Systems 被引量:6
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作者 Mohsen Timoumi 《Applied Mathematics》 2011年第7期846-853,共8页
Considering a decomposition R2N=A⊕B of R2N , we prove in this work, the existence of at least (1+dimA) geometrically distinct periodic solutions for the first-order Hamiltonian system Jx'(t)+H'(t,x(t))+e(t)=0... Considering a decomposition R2N=A⊕B of R2N , we prove in this work, the existence of at least (1+dimA) geometrically distinct periodic solutions for the first-order Hamiltonian system Jx'(t)+H'(t,x(t))+e(t)=0 when the Hamiltonian H(t,u+v) is periodic in (t,u) and its growth at infinity in v is at most like or faster than |v|a, 0≤ae is a forcing term. For the proof, we use the Least Action Principle and a Generalized Saddle Point Theorem. 展开更多
关键词 HAMILTONIAN Systems Partial NONLINEARITY multiple periodIC Solutions Critical Point Theory
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Group Decision-Making Method with Incomplete Intuitionistic Fuzzy Preference Relations Based on a Generalized Multiplicative Consistent Concept
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作者 Xiaoyun Lu Jiuying Dong +1 位作者 Hecheng Li Shuping Wan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第9期881-907,共27页
Based on the analyses of existing preference group decision-making(PGDM)methods with intuitionistic fuzzy preference relations(IFPRs),we present a new PGDM framework with incomplete IFPRs.A generalized multiplicative ... Based on the analyses of existing preference group decision-making(PGDM)methods with intuitionistic fuzzy preference relations(IFPRs),we present a new PGDM framework with incomplete IFPRs.A generalized multiplicative consistent for IFPRs is defined,and a mathematical programming model is constructed to supplement the missing values in incomplete IFPRs.Moreover,in this study,another mathematical programming model is constructed to improve the consistency level of unacceptably multiplicative consistent IFPRs.For group decisionmaking(GDM)with incomplete IFPRs,three reliable sources influencing the weights of experts are identified.Subsequently,a method for determining the weights of experts is developed by simultaneously considering three reliable sources.Furthermore,a targeted consensus process(CPR)is developed in this study with reference to the actual situation of the consensus level of each IFPR.Meanwhile,in response to the proposed multiplicative consistency definition,a novel method for determining the optimal priority weights of alternatives is redefined.Lastly,based on the above theory,a novel GDM method with incomplete IFPRs is developed,and the comparative and sensitivity analysis results demonstrate the utility and superiority of this work. 展开更多
关键词 Intuitionistic fuzzy preference relations multiplicative consistency CONSENSUS optimization model group decision-making
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Periodic Solutions for the Higher Order Differential Equations with Multiple Delays
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作者 梁心 从福仲 《Northeastern Mathematical Journal》 CSCD 2008年第6期558-564,共7页
By Fourier analysis techniques and Schauder fixed point theorem, we study the existence of periodic solutions for a class of even order differential equations with multiple delays. The result obtained is a generalizat... By Fourier analysis techniques and Schauder fixed point theorem, we study the existence of periodic solutions for a class of even order differential equations with multiple delays. The result obtained is a generalization of the results developed by W. Layton to the case of multiple delays. 展开更多
关键词 (2k)th-order differential equation multiple delay periodic solution Schauder fixed point theorem
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Multiple Period Repair Kit Problem with Capacity Considerations
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作者 Michael Gorman 《Journal of Transportation Technologies》 2016年第5期457-468,共12页
The repair kit problem seeks an optimal stock of parts for a repair kit for purposes of remote repairs. This problem has often been studied when restocking is possible between each order, or when the number of orders ... The repair kit problem seeks an optimal stock of parts for a repair kit for purposes of remote repairs. This problem has often been studied when restocking is possible between each order, or when the number of orders is known between each restocking. This research evaluates a model for the repair kit stocking problem for which there is multiple-period demand with a known time interval between each restocking, but an unknown number of on-site repair visits is required during the restocking period. Most previous work focuses on minimum cost subject to some minimum service level;in the case where the value of technician time and customer service is relatively large, the space constraint of the kit and volume of parts comes into play. This work contributes to the literature by testing the robustness of a heuristic originally proposed by [1] in a field study. We conduct numerical experiments to evaluate the heuristic over a wide range of parameterizations. Our results indicate that the heuristic performs close to optimum, and its performance improves as the problem size grows. 展开更多
关键词 Repair Kit Stocking Problem multiple period
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MULTIPLE SOLUTIONS FOR HAMILTONIAN SYSTEMS WITH PERIODIC NONLINEARITY AND STRONG RESONANCE
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作者 刘嘉荃 《Acta Mathematica Scientia》 SCIE CSCD 1991年第4期417-423,共7页
I. Introduction In this paper we are looking for solutions of the following Hamiltonian system of second order: where x= (x1, x2) and V satisfies (V. 1) V: R×R2→R is a C1-function, 1-periodic In t, (V.2) V... I. Introduction In this paper we are looking for solutions of the following Hamiltonian system of second order: where x= (x1, x2) and V satisfies (V. 1) V: R×R2→R is a C1-function, 1-periodic In t, (V.2) V is periodic in x1 with the period T>0, (V. 3) V→O, Vx→O as |x2|→∞, uniformly in (t, x1). 展开更多
关键词 multiple SOLUTIONS FOR HAMILTONIAN SYSTEMS WITH periodIC NONLINEARITY AND STRONG RESONANCE
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HEURISTIC PARTICLE SWARM OPTIMIZATION ALGORITHM FOR AIR COMBAT DECISION-MAKING ON CMTA 被引量:18
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作者 罗德林 杨忠 +2 位作者 段海滨 吴在桂 沈春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第1期20-26,共7页
Combining the heuristic algorithm (HA) developed based on the specific knowledge of the cooperative multiple target attack (CMTA) tactics and the particle swarm optimization (PSO), a heuristic particle swarm opt... Combining the heuristic algorithm (HA) developed based on the specific knowledge of the cooperative multiple target attack (CMTA) tactics and the particle swarm optimization (PSO), a heuristic particle swarm optimization (HPSO) algorithm is proposed to solve the decision-making (DM) problem. HA facilitates to search the local optimum in the neighborhood of a solution, while the PSO algorithm tends to explore the search space for possible solutions. Combining the advantages of HA and PSO, HPSO algorithms can find out the global optimum quickly and efficiently. It obtains the DM solution by seeking for the optimal assignment of missiles of friendly fighter aircrafts (FAs) to hostile FAs. Simulation results show that the proposed algorithm is superior to the general PSO algorithm and two GA based algorithms in searching for the best solution to the DM problem. 展开更多
关键词 air combat decision-making cooperative multiple target attack particle swarm optimization heuristic algorithm
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Measurement of overburden failure zones in close-multiple coal seams mining 被引量:8
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作者 Yang Li Yuqi Ren +3 位作者 Syd S.Peng Haozhou Cheng Nan Wang Junbo Luo 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第1期43-50,共8页
In the Kaiping Coal field,mining of five coal seams,located within 80 m in the Kailuan Group,#5,#7,#8,#9 and#12 coal seam,is difficult due to small interburden thickness,concentrated stress distributions,high coal sea... In the Kaiping Coal field,mining of five coal seams,located within 80 m in the Kailuan Group,#5,#7,#8,#9 and#12 coal seam,is difficult due to small interburden thickness,concentrated stress distributions,high coal seam metamorphism,and complex geological conditions.By using the ZTR12 geological penetration radar(GPR)survey combined with borehole observations,the overburden caving due to mining of the five coals seams was measured.The development characteristics of full-cover rock fractures after mining were obtained from the GPR scan,which provides a measurement basis for the control of rock strata in close multiple coal seam mining.For the first time,it was found that the overburden caving pattern shows a periodic triangular caved characteristic.Furthermore,it is proposed that an upright triangular collapsed pile masonry and an inverted triangular with larger fragments piled up alternately appear in the lower gob.The research results show that the roof structure formed in the gob area can support the key overlying strata,which is beneficial to ensure the integrity and stability of the upper coal seams in multiple-seam mining of close coal seams. 展开更多
关键词 Overburden measurement GPR survey Close multiple coal seam Secondary roof break periodic triangular cave Overburden caving
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Threat sequencing of multiple UCAVs with incomplete information based on game theory 被引量:3
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作者 LI Shouyi CHEN Mou +1 位作者 WU Qingxian WANG Yuhui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第4期986-996,共11页
The threat sequencing of multiple unmanned combat air vehicles(UCAVs) is a multi-attribute decision-making(MADM)problem. In the threat sequencing process of multiple UCAVs,due to the strong confrontation and high dyna... The threat sequencing of multiple unmanned combat air vehicles(UCAVs) is a multi-attribute decision-making(MADM)problem. In the threat sequencing process of multiple UCAVs,due to the strong confrontation and high dynamics of the air combat environment, the weight coefficients of the threat indicators are usually time-varying. Moreover, the air combat data is difficult to be obtained accurately. In this study, a threat sequencing method of multiple UCAVs is proposed based on game theory by considering the incomplete information. Firstly, a zero-sum game model of decision maker( D) and nature(N)with fuzzy payoffs is established to obtain the uncertain parameters which are the weight coefficient parameters of the threat indicators and the interval parameters of the threat matrix. Then,the established zero-sum game with fuzzy payoffs is transformed into a zero-sum game with crisp payoffs(matrix game) to solve. Moreover, a decision rule is addressed for the threat sequencing problem of multiple UCAVs based on the obtained uncertain parameters. Finally, numerical simulation results are presented to show the effectiveness of the proposed approach. 展开更多
关键词 threat sequencing multiple unmanned combat air vehicles(UCAVs) multi-attribute decision-making(MADM) game theory incomplete information
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Application of the Modality of Multiple Disciplinary Team for a Perioperative Patient with Suspected Novel Coronavirus Pneumonia and Cervical Spine Fracture in Nursing 被引量:2
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作者 Yuanli Chen Yingying Zhang +3 位作者 Huijun Zhou Wenzhen Li Ruiting Hao Liang Peng 《International Journal of Clinical Medicine》 2020年第12期769-777,共9页
With the explosive spread of novel coronavirus pneumonia, a major public major public health emergency has been declared around the world. Our country has come to a crucial stage of “external defense input, internal ... With the explosive spread of novel coronavirus pneumonia, a major public major public health emergency has been declared around the world. Our country has come to a crucial stage of “external defense input, internal defense rebound” and strict quarantine measures are taken in all ports of entry throughout the country. Operations on patients with cervical spine during the quarantine, which not only increases the risk of surgical treatment, but also increases the difficulty of perioperative nursing. The objective is to explore the result of application of the modality of multiple disciplinary team for a perioperative patient with suspected novel coronavirus pneumonia and cervical spine fracture in nursing. The patient’s condition and nursing measures are studied and discussed from various specialist angle through the multidisciplinary team established by the isolation ward, orthopedics department, emergency department, anesthesiology department, operating room, rehabilitation department, psychology department and so on, and the overall and personalized surgical and nursing planning is formed through interdisciplinary advice. The nursing experience is summarized in this paper. 展开更多
关键词 multiple Disciplinary Team Suspected Novel Coronavirus Pneumonia Cervical Spine Fracture Perioperative period NURSING
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Aczel-Alsina Weighted Aggregation Operators of Simplified Neutrosophic Numbers and Its Application in Multiple Attribute Decision Making
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作者 Rui Yong Jun Ye +2 位作者 Shigui Du Aqin Zhu Yingying Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第8期569-584,共16页
The simplified neutrosophic number(SNN)can represent uncertain,imprecise,incomplete,and inconsistent information that exists in scientific,technological,and engineering fields.Hence,it is a useful tool for describing ... The simplified neutrosophic number(SNN)can represent uncertain,imprecise,incomplete,and inconsistent information that exists in scientific,technological,and engineering fields.Hence,it is a useful tool for describing truth,falsity,and indeterminacy information in multiple attribute decision-making(MADM)problems.To suit decision makers’preference selection,the operational flexibility of aggregation operators shows its importance in dealing with the flexible decision-making problems in the SNN environment.To solve this problem,this paper develops the Aczel-Alsina aggregation operators of SNNs for MADM problems in view of the Aczel-Alsina operational flexibility.First,we define the Aczel-Alsina operations of SNNs.Then,the Aczel-Alsina aggregation operators of SNNs are presented based on the defined Aczel-Alsina operations of SNNs.Next,a MADM method is established using the proposed aggregation operators under the SNN environment.Lastly,an illustrative example about slope treatment scheme choices is provided to indicate the practicality and efficiency of the established method.By comparison with the existing relative MADM methods,the results show that the established MADM method can overcome the insufficiency of decision flexibility in the existing MADM methods and demonstrate the metric of flexible decision-making. 展开更多
关键词 Simplified neutrosophic number multiple attribute decision-making aggregation operators
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MULTIPLICITY OF PERIODIC SOLUTIONS FOR SECOND ORDER HAMILTONIAN SYSTEMS WITH MIXED NONLINEARITIES
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作者 Mingwei WANG Fei GUO 《Acta Mathematica Scientia》 SCIE CSCD 2021年第2期371-380,共10页
The multiplicity of periodic solutions for a class of second order Hamiltonian system with superquadratic plus subquadratic nonlinearity is studied in this paper.Obtained via the Symmetric Mountain Pass Lemma,two resu... The multiplicity of periodic solutions for a class of second order Hamiltonian system with superquadratic plus subquadratic nonlinearity is studied in this paper.Obtained via the Symmetric Mountain Pass Lemma,two results about infinitely many periodic solutions of the systems extend some previously known results. 展开更多
关键词 multiplICITY periodic solutions second order Hamiltonian systems Symmetric Mountain Pass Lemma
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Internal Transactions for Multiple Risky Assets
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作者 Qiong Zhang Shuang Chen 《Open Journal of Statistics》 2019年第1期85-99,共15页
Most of the articles about insider trading assume that there is only one risky asset in the market. On the basis of these papers, this thesis is mainly divided into three parts to study the situation of multiple risky... Most of the articles about insider trading assume that there is only one risky asset in the market. On the basis of these papers, this thesis is mainly divided into three parts to study the situation of multiple risky assets in the market. In the first part, the situation of multiple risky assets in the market when two transactions are in progress is studied and then, the equilibrium when the market requires the internal traders to disclose the trading volume after each transaction is analyzed. In the second part, the equilibrium of multi-period based on the two phases of transaction is derived. The third part is the summary of the paper. 展开更多
关键词 INSIDER TRADING multiple Risky ASSETS MULTI-period Noise TRADER
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Simultaneous Bilateral Thoracoscopic Pneumonectomy for Early Multiple Primary Lung Cancer Feasibility Analysis
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作者 Zhonglong Zheng Tao Li +2 位作者 Yang Chen Yang Zhang Pan Zhang 《Proceedings of Anticancer Research》 2021年第3期34-38,共5页
Objective:To analyze the feasibility of simultaneous bilateral thoracoscopic lung resection in the treatment of multiple primary lung cancers in the early stage.Methods:The study time range is between March 2019 and M... Objective:To analyze the feasibility of simultaneous bilateral thoracoscopic lung resection in the treatment of multiple primary lung cancers in the early stage.Methods:The study time range is between March 2019 and March 2021.A sample of 30 patients with early multiple primary lung cancer admitted to this hospital were included,and they were divided into a study group,a control group,and samples within the group using a random number table scheme n=15,patients in the control group underwent staged bilateral thoracoscopic pneumonectomy,and patients in the study group underwent bilateral thoracoscopic pneumonectomy at the same time.The indicators of the two groups were compared and analyzed.Results:There was no significant difference in the operation time and intraoperative blood loss between the two groups(P>0.05).There were significant differences in the VAS score,total length of hospital stay,and total surgical costs on the first day after surgery(P<0.05);there was no significant difference in the two groups'postoperative recovery indicators and the incidence of complications(P>0.05).Conclusion:It is safe and feasible to treat patients with multiple primary lung cancer in both lungs at the same time with simultaneous bilateral thoracoscopic surgery,and is suitable for promotion. 展开更多
关键词 The same period Bilateral thoracoscopic lung resection Early multiple primary lung cancer
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Cooperative Decision-Making for Multiple UAVs Autonomous Confrontation
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作者 Han Wang Xiaolong Liang +4 位作者 Jiaqiang Zhang Aiwu Yang Yueqi Hou Ning Wang Aoyu Zheng 《Guidance, Navigation and Control》 2024年第1期176-199,共24页
This paper presents a rule-based framework for addressing decision-making problems within the context of the "UI-STRIVE"Competition.First,two distinct autonomous confrontation scenarios are described:autonom... This paper presents a rule-based framework for addressing decision-making problems within the context of the "UI-STRIVE"Competition.First,two distinct autonomous confrontation scenarios are described:autonomous air combat and cooperative interception.Second,a State-Event-Condition-Action(SECA)decision-making framework is developed,which integrates thefinite state machine and event-condition-action frameworks.This framework provides three products to describe rules,i.e.the SECA model,the SECA state chart,and the SECA rule description.Third,the situation assessment and target assignment during autonomous air combat are investigated,and the mathematical models are established.Finally,the decisionmaking model's rationality and feasibility are verified through data simulation and analysis. 展开更多
关键词 Rule-based decision-making air combat multiple UAVs autonomous confrontation
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The Zhaxikang Vein-type Pb-Zn-Ag-Sb Deposit in Himalayan Orogen, Tibet: Product by Overprinting and Remobilization Processes during Post-collisional Period 被引量:5
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作者 LIANG Wei HOU Zengqian +2 位作者 ZHENG Yuanchuan YANG Zhusen LI Zhenqing 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期682-705,共24页
The Zhaxikang Pb-Zn-Ag-Sb deposit, the largest polymetallic deposit known in the Himalayan Orogen of southern Tibet, is characterized by vein-type mineralization that hosts multiple mineral assemblages and complicated... The Zhaxikang Pb-Zn-Ag-Sb deposit, the largest polymetallic deposit known in the Himalayan Orogen of southern Tibet, is characterized by vein-type mineralization that hosts multiple mineral assemblages and complicated metal associations. The deposit consists of at least six steeply dipping vein- type orebodies that are hosted by Early Jurassic black carbonaceous slates and are controlled by a Cenozoic N-S-striking normal fault system. This deposit records multiple stages of mineralization that include an early period (A) of massive coarse-grained galena-sphalerite deposition and a later period (B) of Sb-bearing vein-type mineralization. Period A is only associated with galena-sphalerite mineralization, whereas period B can be subdivided into ferrous rhodochrosite-sphalerite-pyrite, quartz -sulfosalt-sphalerite, calcite-pyrite, quartz-stibnite, and quartz-only stages of mineralization. The formation of brecciated galena and sphalerite ores during period A implies reworking of pre-existing Pb -Zn sulfides by Cenozoic tectonic deformation, whereas period B mineralization records extensive open- space filling during ore formation. Fluid inclusion microthermometric data indicate that both periods A and B were associated with low-medium temperature (187-267℃) and low salinity (4.00-10.18% wt. NaCl equivalent) ore-forming fluids, although variations in the physical-chemical nature of the period B fluids suggest that this phase of mineralization was characterized by variable water/rock ratios. Microprobe analyses indicate that Fe concentrations in sphalerite decrease from period A to period B, and can be divided into three groups with FeS concentrations of 8.999-9.577, 7.125-9.109, 5.438-1.460 mol.%. The concentrations of Zn, Sb, Pb, and Ag within orebodies in the study area are normally distributed in both lateral and vertical directions, and Pb, Sb, and/or Ag concentrations are positive correlation within the central part of these orebodies, but negatively correlate in the margins. Sulfide S isotope compositions are highly variable (4‰-13‰), varying from 4‰ to 11‰ in period A and 10‰ to 1‰ in period B. The Pb isotope within these samples is highly radiogenic and defines linear trends in 206pb/204pb vs. 207pb/204pb and 206pb/204pb vs. 208pb/204pb diagrams, respectively. The S and Pb isotopic characteristics indicate that the period B orebodies formed by mixing of Pb-Zn sulfides and regional Sb- bearing fluids. These features are indicative of overprinting and remobilization of pre-existing Pb-Zn sulfides by Sb-bearing ore-forming fluids during a post-collisional period of the Himalayan Orogeny. The presence of similar ore types in the north Rhenish Massif that formed after the Variscan Orogeny suggests that Zhaxikang-style mineralization may be present in other orogenic belts, suggesting that this deposit may guide Pb-Zn exploration in these areas. 展开更多
关键词 POLYMETALLIC multiple period and stage mineralization overprinting and remobilization orogenic belt Zhaxikang TIBET
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