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Quantifying the Microeconomic and Macroeconomic Impact of the Recent Crude Oil Price Fluctuations

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Open Journal of Statistics 2016年第4期6卷 605-615页

作者： Peng Xu Utsav Adhikari Lei Guo Deepa Sathaye Jihua Wang Dongliang Yi Yizhi Zhu department of Industrial and enterprise Systems engineering University of Illinois Urbana IL USA

This study analyzed the potential impact of the increased oil volatility on the industries and the global economy. Specifically, it separated the oil price fluctuations into positive and negative components, and modeled the return of industry portfolios with them. Next, the sensitivity of the airline industry to oil price was investigated to gauge the effectiveness of their hedging strategies, with the hope that the methodology can be extended to other industries. In addition, this paper explored the macroeconomic impact of oil price movements by examining the benchmarks such as GDP and CPI.

关键词： Crude Oil Airline Hedging Asymmetric Effects Microeconomics Macroeconomics

Dynamic Pricing with Stochastic Reference Price Effect

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Journal of the Operations Research Society of China 2019年第1期7卷 107-125页

作者： Xin Chen Zhen-Yu Hu Yu-Han Zhang department of Industrial enterprise and Systems engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA NUS Business School National University of SingaporeSingapore 119245Singapore Two Sigma Investments New YorkNY 10036USA

We study a dynamic pricing problem of a firm facing stochastic reference price *** is incorporated in the formation of reference prices to capture either consumers’heterogeneity or exogenous factors that affect consumers’memory *** apply the stochastic optimal control theory to the problem and derive an explicit expression for the optimal pricing *** explicit expression allows us to obtain the distribution of the steady-state reference *** compare the expected steadystate reference price to the steady-state reference price in a model with deterministic reference price effect,and we find that the former one is always *** numerical study shows that the two steady-state reference prices can have opposite sensitivity to the problem parameters and the relative difference between the two can be very significant.

关键词： Reference price effect Dynamic pricing Stochastic optimal control

Evolutionary Algorithms for Solving Unconstrained Multilevel Lot-Sizing Problem with Series Structure

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Journal of Shanghai Jiaotong university(Science) 2012年第1期17卷 39-44页

作者：韩毅蔡建湖 IKOU Kaku 李延来陈以增唐加福 College of Economics and Management Zhejiang University of Technology Research Center for Technology Innovation and enterprise Internationalization Zhejiang University of Technology department of Management Science and engineering Akita Prefectural University School of Logistics Southwest Jiaotong University College of International Business and Management Shanghai University Institute of Systems engineering Northeastern University

This paper presents a comparative study of evolutionary algorithms which are considered to be effective in solving the multilevel lot-sizing problem in material requirement planning(MRP)*** evolutionary algorithms(simulated annealing(SA),particle swarm optimization(PSO)and genetic algorithm(GA))are *** evaluating the performances of algorithms,the distribution of total cost(objective function)and the average computational time are *** a result,both GA and PSO have better cost performances with lower average total costs and smaller standard *** the scale of the multilevel lot-sizing problem becomes larger,PSO is of a shorter computational time.

关键词： simulated annealing(SA) genetic algorithm(GA) particle swarm optimization(PSO) multilevel lot-sizing problem

GDM： A New Graph Based Data Model Using Functional Abstractionx

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Journal of Computer Science & Technology 2006年第3期21卷 430-438页

作者： Sankhayan Choudhury Nabendu Chaki Swapan Bhattacharya department of Computer Science and engineering University of Calcutta India department of Computer Science and engineering Jadavpur University India

In this paper, a Graph-based semantic Data Model （GDM） is proposed with the primary objective of bridging the gap between the human perception of an enterprise and the needs of computing infrastructure to organize information in some particular manner for efficient storage and retrieval. The Graph Data Model （GDM） has been proposed as an alternative data model to combine the advantages of the relational model with the positive features of semantic data models. The proposed GDM offers a structural representation for interacting to the designer, making it always easy to comprehend the complex relations amongst basic data items. GDM allows an entire database to be viewed as a Graph （V, E） in a layered organization. Here, a graph is created in a bottom up fashion where V represents the basic instances of data or a functionally abstracted module, called primary semantic group （PSG） and secondary semantic group （SSG）. An edge in the model implies the relationship among the secondary semantic groups. The contents of the lowest layer are the semantically grouped data values in the form of primary semantic groups. The SSGs are nothing but the higher-level abstraction and are created by the method of encapsulation of various PSGs, SSGs and basic data elements. This encapsulation methodology to provide a higher-level abstraction continues generating various secondary semantic groups until the designer thinks that it is sufficient to declare the actual problem domain. GDM, thus, uses standard abstractions available in a semantic data model with a structural representation in terms of a graph. The operations on the data model are formalized in the proposed graph algebra. A Graph Query Language （GQL） is also developed, maintaining similarity with the widely accepted user-friendly SQL. Finally, the paper also presents the methodology to make this GDM compatible with the distributed environment, and a corresponding query processing technique for distributed environment is also sugg

关键词： graph data model semantic group semantic data model distributed database fragmentation and allocation schema

Enhanced CO2 electroreduction on armchair graphene nanoribbons edge-decorated with copper

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Nano Research 2017年第5期10卷 1641-1650页

作者： Guizhi Zhu Singapore-Peking University Research Centre Campus for Research Excellence & Technological Enterprise (CREATE) Singapore 138602 Singapore department of Materials Science and engineering Peking University Beijing 100871 China Institute of Modern Physics Shaanxi Key Laboratory for Theoretical Physics Frontiers Northwest University Xi'an 710069 China School of Materials Science and engineering Nanyang Technological University Singapore 639798 Singapore School of Mechanical and Aerospace engineering Nanyang Technological University Singapore 639798 Singapore

Inspired by the recent experimental synthesis of graphene nanoribbons （GNKs） and theoretical research on their edge-decoration, we comprehensively studied the electrocatalytic performance of GNRs edge-decorated with Cu for CO2 reduction. Compared to zigzag GNRs, the Cu-terminated armchair GNRs with a width of n = 3p ＋ 2 were more efficient catalysts for producing methanol from CO2 with a free energy barrier of less than 0.5 eV, offering the advantages of a lower overpotential and higher selectivity than bulk Cu and other graphene-supported Cu structures. On the other hand, the competing hydrogen evolution reaction could be effectively suppressed by Cu-terminated armchair GNRs. Hence, the edge-decorated GNRs offer great flexibility for tuning the catalytic efficiency and selectivity for CO2 electroreduction.

关键词： carbon dioxide density functionalcalculations edge effects electrocatalysis graphene nanoribbons

An analysis of silver candlesticks from a casting point of view:originals,copies,forgeries

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China Foundry 2010年第1期7卷 68-75页

作者： Jaromir Audy Emil Evin Faculty of Regional Professional Studies School of Enterprise and TechnologyEdith Cowan UniversitySouth West Campus BunburyAustralia 6230 department Technologies and Materials Faculty of Mechanical EngineeringTechnical University KosiceM-siarska 74Ko-iceSlovakia 04001

Collecting silver artefacts has traditionally been a very popular *** is addictive,therefore the number of potential collectors and investors appears to grow each ***,increases in the interest and buying potentials resulted in a number of forgeries manufactured and introduced to the open antique *** items such as early silver candlesticks dictate a very high price,for many high quality fakes show very good appearances and matching similarities with *** copies are traditionally manufactured by casting using the original items as *** details and variances in design features,position and shape of hallmarks,including the final surface quality are usual features to distinguish the fakes from the *** paper presents results of a study conducted on several silver candlesticks,including two artefacts bearing features of those produced in the mid 18th century,one original Italian candelabrum from Fascist era,and small candlesticks made in the early 20th ***,the paper presents some interesting contemporary coins-replicas of many those produced in different *** coins were offered for sale by unscrupulous dealers via auctions and *** the main results and findings from this study are discussed from a manufacturing point of view,such as fabrication technology,surface quality and hallmarks,which will help the collectors,dealers and investors to detect and avoid forgeries.

关键词： candlesticks candelabra originals copies forgeries silver manufacturing technology hallmarks

Structural Design and Control Strategy Analysis of Micro/Nano Transmission Platform

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Transactions of Nanjing University of Aeronautics and Astronautics 2014年第5期31卷 484-491页

作者：林超纪久祥陶友淘霍德鸿才立忠程凯 State Key Laboratory of Mechanical Transmission Chongqing University School of Mechanical and Systems engineering Newcastle UniversityNewcastle Upon TyneNE1 7RUUK Advanced Manufacturing and enterprise engineering department Brunel UniversityUxbridgeMiddlesex UB8 3PHUK

A fully flexure micro/nano transmission platform(MNTP)which has five degrees of freedom is designed on the basis of bridge type amplification *** to the kinematic theory and the elastic beam theory,the theoretical output displacement equation of the platform is derived,and then piezoelectric actuator(PZT)is ***,a full closed-loop control strategy of the platform is established using the feedforward proportional-integral-derivative(PID)compound control algorithm based on the Preisach ***,the total transfer function of the micro positioning system is derived,and the calculation method of output signal is ***,the theoretical output displacement is verified by finite element analysis(FEA)and positioning experiments.

关键词： bridge type amplification mechanism(BTAM) micro / nano transmission platform(MNTP) piezoelectric actuator(PZT) finite element analysis(FEA) control strategies

enterprise-wide optimization of integrated planning and scheduling for refinery-petrochemical complex with heuristic algorithm

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Frontiers of Chemical Science and engineering 2023年第10期17卷 1516-1532页

作者： Lifeng Zhang Haoyang Hu Zhiquan Wang Zhihong Yuan Bingzhen Chen State Key Laboratory of Chemical engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China department of Chemical engineering Tsinghua UniversityBeijing 100084China

This paper focuses on the integrated problem of long-term planning and short-term scheduling in a largescale refinery-petrochemical complex,and considers the overall manufacturing process from the upstream refinery to the downstream petrochemical *** time scales are incorporated from the planning and scheduling *** the end of each discrete time period,additional constraints are imposed to ensure material balance between different time *** time representation is applied to the planning subproblem,while continuous time is applied to the scheduling of ethylene cracking and polymerization processes in the petrochemical *** enterprise-wide mathematical model is formulated through mixed integer nonlinear *** solve the problem efficiently,a heuristic algorithm combined with a convolutional neural network(CNN),is *** variables are used as the CNN input,leading to the integration of a data-driven approach and classical optimization by which a heuristic algorithm is *** results do not only illustrate the detailed operations in a refinery and petrochemical complex under planning and scheduling,but also confirm the high efficiency of the proposed algorithm for solving large-scale problems.

关键词： planning scheduling refinery-petrochemical convolutional neural network heuristic algorithm

A VNS-NPGA Approach to Multi-Objective Optimization of Hub-and-spoke Logistics Network

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Journal of Traffic and Transportation engineering(English Edition) 2024年

作者： Changxi Ma Chuwei Shi Yun Yang Yongpeng Zhao Zhuye Xu Bo Du School of Traffic and Transportation， Lanzhou Jiaotong University Key Laboratory of Railway lndustry on Plateau Railway Transportation Intelligent Management and Control， Lanzhou Jiaotong University School of Tourism and Management， Yangling Vocational and Technical College School of New Energy and Power engineering， Lanzhou Jiaotong University National engineering Research Center of Highway Maintenance Technology， Changsha University of Science & Technology SMART Infrastructure Facility， University of Wollongong

To realize low-cost freight transport in the logistics network and improve the network operation efficiency， a multi-objective optimization model and the corresponding algorithm for a hub-and-spoke logistics network are proposed based on the multi-level location of hub points and channels layout. By considering the structure of the multi-level hub-and-spoke logistics network and the features of the connectivity between the hub and spoke points， the multi-objective optimization model is constructed with two objectives of minimizing the total network operation costs and the total network service time. By considering the characteristics of decision variables and models， a Variable Neighborhood Search (VNS)-Niched Pareto Genetic Algorithm (NPGA) approach with a three-stage encoding structure chromosome is proposed， where the VNS algorithm nested in NPGA is used for individual variable neighborhood search to optimize individual channel level genes， and NPGA is adopted to solve the multi-objective optimization model. To evaluate the performance of the proposed VNS-NPGA approach， a real-life case study based on a small-scale Australia Post data set was conducted， and 25 nodes of the Australia Post and 14 nodes of the Gansu Province 3-level hub-and-spoke logistics networks were established， respectively. The analysis results indicated that the network structure of multi-level hub points could avoid the detour problem existing in the traditional hub-and-spoke network， and showed better applicability in the narrow geographical structure. Compared to the traditional multi-objective evolutionary algorithms， VNS-NPGA can obtain better solutions through the distributed optimization of channel levels， avoiding the problem that a single algorithm cannot effectively deal with coupling relationships in genes.

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