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Strategic Contracting for Software Upgrade Outsourcing in Industry 4.0
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作者 Cheng Wang Zhuowei Zheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1563-1592,共30页
The advent of Industry 4.0 has compelled businesses to adopt digital approaches that combine software toenhance production efficiency. In this rapidly evolving market, software development is an ongoing process thatmu... The advent of Industry 4.0 has compelled businesses to adopt digital approaches that combine software toenhance production efficiency. In this rapidly evolving market, software development is an ongoing process thatmust be tailored to meet the dynamic needs of enterprises. However, internal research and development can beprohibitively expensive, driving many enterprises to outsource software development and upgrades to externalservice providers. This paper presents a software upgrade outsourcing model for enterprises and service providersthat accounts for the impact of market fluctuations on software adaptability. To mitigate the risk of adverseselection due to asymmetric information about the service provider’s cost and asymmetric information aboutthe enterprise’s revenues, we propose pay-per-time and revenue-sharing contracts in two distinct informationasymmetry scenarios. These two contracts specify the time and transfer payments for software upgrades. Througha comparative analysis of the optimal solutions under the two contracts and centralized decision-making withfull-information, we examine the characteristics of the solutions under two information asymmetry scenarios andanalyze the incentive effects of the two contracts on the various stakeholders. Overall, our study offers valuableinsights for firms seeking to optimize their outsourcing strategies and maximize their returns on investment insoftware upgrades. 展开更多
关键词 Software upgrade outsourcing the principal-agent information asymmetry reverse selection contract design
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Mitigating Blackhole and Greyhole Routing Attacks in Vehicular Ad Hoc Networks Using Blockchain Based Smart Contracts
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作者 Abdulatif Alabdulatif Mada Alharbi +1 位作者 Abir Mchergui Tarek Moulahi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期2005-2021,共17页
The rapid increase in vehicle traffic volume in modern societies has raised the need to develop innovative solutions to reduce traffic congestion and enhance traffic management efficiency.Revolutionary advanced techno... The rapid increase in vehicle traffic volume in modern societies has raised the need to develop innovative solutions to reduce traffic congestion and enhance traffic management efficiency.Revolutionary advanced technology,such as Intelligent Transportation Systems(ITS),enables improved traffic management,helps eliminate congestion,and supports a safer environment.ITS provides real-time information on vehicle traffic and transportation systems that can improve decision-making for road users.However,ITS suffers from routing issues at the network layer when utilising Vehicular Ad Hoc Networks(VANETs).This is because each vehicle plays the role of a router in this network,which leads to a complex vehicle communication network,causing issues such as repeated link breakages between vehicles resulting from the mobility of the network and rapid topological variation.This may lead to loss or delay in packet transmissions;this weakness can be exploited in routing attacks,such as black-hole and gray-hole attacks,that threaten the availability of ITS services.In this paper,a Blockchain-based smart contracts model is proposed to offer convenient and comprehensive security mechanisms,enhancing the trustworthiness between vehicles.Self-Classification Blockchain-Based Contracts(SCBC)and Voting-Classification Blockchain-Based Contracts(VCBC)are utilised in the proposed protocol.The results show that VCBC succeeds in attaining better results in PDR and TP performance even in the presence of Blackhole and Grayhole attacks. 展开更多
关键词 Blockchain data privacy machine learning routing attacks smart contract VANET
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Homotopy analysis solutions for the asymmetric laminar flow in a porous channel with expanding or contracting walls 被引量:7
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作者 X.-H. Si L.-C. Zheng +1 位作者 X.-X. Zhang Y. Chao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第2期208-214,共7页
In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. Homot... In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. Homotopy analysis method (HAM) is employed to obtain the expres- sions for velocity fields. Graphs are sketched for values of parameters and associated dynamic characteristics, especially the expansion ratio, are analyzed in detail. 展开更多
关键词 Homotopy analysis method · Expanding or contracting wall · Asymmetric laminar flow · Porous channel · Expansion ratio
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A secure spectrum auction scheme without the trusted party based on the smart contract 被引量:2
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作者 Jiaqi Wang Ning Lu +2 位作者 Qingfeng Cheng Lu Zhou Wenbo Shi 《Digital Communications and Networks》 SCIE CSCD 2021年第2期223-234,共12页
With the development of communication 5G networks and technologies,spectrum resources are increasingly scarce.The scarcity of the spectrum resource makes market-driven spectrum auction become an important means of spe... With the development of communication 5G networks and technologies,spectrum resources are increasingly scarce.The scarcity of the spectrum resource makes market-driven spectrum auction become an important means of spectrum allocation,and due to the complexity of the network environment,the security of spectrum auctions can not be ignored.Most existing secure spectrum auction schemes introduce a semi-honest agent to complete spectrum auction.However,the hypothetical semi-honest model does not guarantee the security of spectnim auction in the actual application scenario,which may lead to potential security threats:the agent may reveal the privacy of bidders,agent or auctioneer may collude with the bidder to manipulate the spectrum auction,and so on.In this paper,a secure spectrum auction scheme without a trusted party is proposed based on the smart contract technology,and the smart contract written into the blockchain replaces the traditional semi-honest agent to cooperate with the auctioneer server to complete the auction.In order to ensure the security of our scheme,a secure spectrum auction protocol is designed,in which the Software Guard Extensions(SGX)technology and Paillier cryptosystem are used to protect the privacy of bidders.Public verification is provided in our protocol by using extensive Pedersen commitment,which prevents the auctioneer server and the bidder from colluding with each other and verifies group bid sum values.Finally,the security analysis is given to propose several types of attacks that can be defended.Besides,theoretical analysis and simulation experiments of our protocol are also provided. 展开更多
关键词 5g Secure spectrum auction Bidders'bids'privacy Smart contract Public verification
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Research on optimal intelligent routing algorithm for IoV with machine learning and smart contract 被引量:1
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作者 Baofeng Ji Mingkun Zhang +4 位作者 Ling Xing Xiaoli Li Chunguo Li Congzheng Han Hong Wen 《Digital Communications and Networks》 SCIE CSCD 2023年第1期47-55,共9页
The huge increase in the communication network rate has made the application fields and scenarios for vehicular ad hoc networks more abundant and diversified and proposed more requirements for the efficiency and quali... The huge increase in the communication network rate has made the application fields and scenarios for vehicular ad hoc networks more abundant and diversified and proposed more requirements for the efficiency and quality of data transmission.To improve the limited communication distance and poor communication quality of the Internet of Vehicles(IoV),an optimal intelligent routing algorithm is proposed in this paper.Combined multiweight decision algorithm with the greedy perimeter stateless routing protocol,designed and evaluated standardized function for link stability.Linear additive weighting is used to optimize link stability and distance to improve the packet delivery rate of the IoV.The blockchain system is used as the storage structure for relay data,and the smart contract incentive algorithm based on machine learning is used to encourage relay vehicles to provide more communication bandwidth for data packet transmission.The proposed scheme is simulated and analyzed under different scenarios and different parameters.The experimental results demonstrate that the proposed scheme can effectively reduce the packet loss rate and improve system performance. 展开更多
关键词 IoV Machine learning Smart contract Routing algorithm GPSR Relay transmission
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Mechanical Proofs about BW Multi-Party Contract Signing Protocol 被引量:1
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作者 ZHANG Ningrong ZHANG Xingyuan WANG Yuanyuan 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1516-1520,共5页
We report on the verification of a multi-party contract signing protocol described by Baum-Waidner and Waidner (BW). Based on Paulson's inductive approach, we give the protocol model that includes infinitely many s... We report on the verification of a multi-party contract signing protocol described by Baum-Waidner and Waidner (BW). Based on Paulson's inductive approach, we give the protocol model that includes infinitely many signatories and contract texts signing simuhaneously. We consider composite attacks of the dishonest signatory and the external intruder, formalize cryptographic primitives and protocol arithmetic including attack model, show formal description of key distribution, and prove signature key secrecy theorems and fairness property theorems of the BW protocol using the interactive theorem prover Isabelle/HOL. 展开更多
关键词 formal verification multi-party contract signing protocol inductive approach MODEL
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A Probe into the Mortgage Rates of Land Contract Management Rights Based on Unified Annual Output Value 被引量:1
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作者 Zhongjun YI 《Asian Agricultural Research》 2013年第9期49-52,共4页
The mortgage of land contract management rights has launched a pilot project in Ningxia,Hubei,Henan,Guizhou,Chongqing and other provinces,municipalities and autonomous regions,which provides a good solution to the pro... The mortgage of land contract management rights has launched a pilot project in Ningxia,Hubei,Henan,Guizhou,Chongqing and other provinces,municipalities and autonomous regions,which provides a good solution to the problem of funds for rural development and plays a huge role in promoting local rural economic development.In the mortgage financing of land contract management rights implemented in various regions,how to determine a scientific,accurate and reasonable mortgage rate of land contract management rights becomes a difficulty troubling the mortgage financing of land.On the basis of unified annual output value of land,this article uses survey method,income capitalization method,and comparison method to analyze the value of land contract management rights,and finally determine the mortgage rates of land contract management rights. 展开更多
关键词 Land CONTRACT management RIGHTS MORTGAGE rates UNI
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Energy Performance Contracting—Business opportunities would be infinite if the “two obstacles” were cracked 被引量:2
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作者 Shi Xiaowen Journalist of China Electric Power News Jia Yulu 《Electricity》 2008年第2期33-35,共3页
Energy Performance Contracting was introduced into China in the mid 1990s. Since western energy service companies came to China, their management pattern has undergone major changes. Why did such changes occur? Mainly... Energy Performance Contracting was introduced into China in the mid 1990s. Since western energy service companies came to China, their management pattern has undergone major changes. Why did such changes occur? Mainly because these companies encountered two difficulties in China: tax and financing. 展开更多
关键词 were cracked Energy Performance contracting two obstacles Business opportunities would be infinite if the EPC
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A CONCEPTUAL FRAMEWORK FOR DELIVERING SUSTAINABLE BUILDING ENERGY EFFICENCY RETROFIT USING THE ENERGY PERFORMANCE CONTRACTING(EPC)IN CHINA 被引量:2
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作者 Pengpeng Xu Edwin H.W.Chan Patrick T.I.Lam 《Journal of Green Building》 2013年第1期177-190,共14页
Sustainable building has become a future development trend in the building sector.Building Energy Efficiency Retrofit(BEER)provides excellent opportunities to reduce energy consumption in existing buildings,and to pro... Sustainable building has become a future development trend in the building sector.Building Energy Efficiency Retrofit(BEER)provides excellent opportunities to reduce energy consumption in existing buildings,and to promote environmental protection,the rational use of resources,occupants’health,all of which helps to improve the sustainability of existing buildings.Energy Performance Contracting(EPC)provided by Energy Service Companies(ESCOs)is a market mechanism to provide financial and technological support for energy efficiency projects.This paper aims to develop a sustainability promotion framework for BEER projects under the EPC mechanism to link the sustainable performance of BEER with the success factors of this EPC mechanism.Different types of building have different energy consumption characteristics.This research focuses on hotel buildings in China.The paper develops a framework for sustainable BEER through an EPC mechanism in hotel buildings based on the EFQM Excellence Model for business quality management.Interviews were conducted with experts from the hotel industry,from energy service companies and with academics.Based on the developed framework,the study has identified 11 performance indicators for sustainable BEER and 28 success factors of an EPC mechanism.This provides significant groundwork for future study in developing an assessment model to evaluate the sustainability of BEER projects. 展开更多
关键词 building energy efficiency hotel retrofit energy performance contracting(EPC) ESCO China
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Condition-based Maintenance Optimization for Gamma Deteriorating Systems under Performance-based Contracting
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作者 Xi Zhu Liang Wen +2 位作者 Juan Li Mingchang Song Qiwei Hu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期34-50,共17页
With the further development of service-oriented,performance-based contracting(PBC)has been widely adopted in industry and manufacturing.However,maintenance optimization problems under PBC have not received enough att... With the further development of service-oriented,performance-based contracting(PBC)has been widely adopted in industry and manufacturing.However,maintenance optimization problems under PBC have not received enough attention.To further extend the scope of PBC’s application in the field of maintenance optimization,we investigate the condition-based maintenance(CBM)optimization for gamma deteriorating systems under PBC.Considering the repairable single-component system subject to the gamma degradation process,this paper proposes a CBM optimization model to maximize the profit and improve system performance at a relatively low cost under PBC.In the proposed CBM model,the first inspection interval has been considered in order to reduce the inspection frequency and the cost rate.Then,a particle swarm algorithm(PSO)and related solution procedure are presented to solve the multiple decision variables in our proposed model.In the end,a numerical example is provided so as to demonstrate the superiority of the presented model.By comparing the proposed policy with the conventional ones,the superiority of our proposed policy is proved,which can bring more profits to providers and improve performance.Sensitivity analysis is conducted in order to research the effect of corrective maintenance cost and time required for corrective maintenance on optimization policy.A comparative study is given to illustrate the necessity of distinguishing the first inspection interval or not. 展开更多
关键词 Performance-based contracting Condition-based maintenance Gamma process Profit maximization Inspection interval
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Improving Right Ventricle Cardiac Function for Repaired Tetralogy of Fallot Patient with Contracting Bands: A Modelling Study
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作者 Han Yu Tal Geva +5 位作者 Rahul HRathod Chun Yang Zheyang Wu Kristen LBilliar Xueying Huang Dalin Tang 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期83-84,共2页
Objective Patients with repaired tetralogy of Fallot(rTOF)account for the majority of cases with late onset right ventricle(RV)failure.The current surgical approach,including pulmonary valve replacement/insertion(PVR)... Objective Patients with repaired tetralogy of Fallot(rTOF)account for the majority of cases with late onset right ventricle(RV)failure.The current surgical approach,including pulmonary valve replacement/insertion(PVR),has yielded mixed results with some patients recover RV function and some do not.An innovative surgical approach was proposed to help ventricle to contract and improve RV function qualified by ejection fraction with one or more active contracting bands.Computational biomechanical modelling is a widely used method in cardiovascular study for investigation of mechanisms governing disease development,quantitative diagnostic and treatment strategies and improving surgical designs for better outcome.Muscle active contraction caused by zero-load sarcomere shortening leads to change of zero-load configurations.In lieu of experimenting using real surgery on animal or human,computational simulations(virtual surgery)were performed to test different band combination and insertion options to identify optimal surgery design and band insertion plan.Methods Cardiac magnetic resonance(CMR)data were obtained from one rTOF patient(sex:male,age:22.5 y)before pulmonary valve replacement surgery.The patient was suffering from RV dilation and dysfunction with RV end-systole volume 254.49ml and end-diastole volume 406.91 mL.A total of 15 computational RV/LV/Patch/Band combination models based on(CMR)imaging were constructed to investigate the influence of different band insertion surgery plans.These models included 5 different band insertion models combined and 3 different band contraction ratio(10%,15%and 20%band zero-stress length reduction).These models included 5 different band insertion models:Model 1 with one band at anterior to the middle of papillary muscle;Model 2 with one band at posterior to the middle of papillary muscle;Model 3 with 2 bands which are the ones from Models 1&2 combined;Model 4 with a band at the base of the papillary muscle;Model 5 with 3 bands which is a combination of Models 3&4.A pre-shrink process was performed on in-vivo begin-filling and end-systole MRI data to obtain diastole and systole zero4oad ventricle geometries.An extra 5%-8%shrinkage was applied to obtain corresponding systole zero-load geometry reflecting myocardium sarcomere shortening.The zero-load band length in systole was 10%,15%and 20%shorter than that in diastole according to their corresponding contraction ratio.The nonlinear Mooney-Rivlin model was used to describe the ventricle material properties with their material parameter values adjusted to match measured data with CMR.The band material properties were in the same scale with healthy right ventricle.The RV/LV/Band model construction and solution procedures were the same as described.Results Model 5 with band contraction ratio of 20%has the ability to improve RV ejection fraction to 41.07%,which represented a 3.61%absolute improvement,or 9.6%relative improvement using pre-PVR ejection fraction as the baseline number.The ejection fractions for Models 1-4 with band contraction ratio of 20%were 39.28%,39.47%,38.87%and 40.34%respectively.Compared to models with band contraction ratio15%and 20%,models with band contraction ratio 10%has the least ability on RV ejection fraction improvement with ejection fraction 38.28%,38.00%,38.81%,38.50%and 39.36%corresponding to Models 1-5.Conclusions This pilot work demonstrated that the band insertion surgery may have great potential to improve post-PVR RV cardiac function for patients with repaired TOF.More band contraction ratio and inserted band number may lead to better post-surgery outcome.Further investigations using in-vitro animal experiments and final patient studies are warranted. 展开更多
关键词 HEART model HEART failure Tetralogy of Fallot CONTRACTION BAND
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Analytic solution to the micropolar-fluid flow through a semi-porous channel with an expanding or contracting wall
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作者 司新辉 郑连存 +1 位作者 张欣欣 晁莹 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第9期1073-1080,共8页
The flow of a micropolar fluid in a semi-porous channel with an expanding or contracting wall is investigated. The governing equations are reduced to ordinary ones by using similar transformations. To get the analytic... The flow of a micropolar fluid in a semi-porous channel with an expanding or contracting wall is investigated. The governing equations are reduced to ordinary ones by using similar transformations. To get the analytic solution to the problem, the homotopy analysis method (HAM) is employed to obtain the expressions for velocity fields. Graphs are sketched and discussed for various parameters, especially the effect of the expansion ratio on velocity and micro-rotation fields. 展开更多
关键词 homotopy analysis method micropolar fluid expanding or contracting wall porous channel
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Perturbation solution to unsteady flow in a porous channel with expanding or contracting walls in the presence of a transverse magnetic field
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作者 司新辉 郑连存 +1 位作者 张欣欣 晁莹 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第2期151-158,共8页
An incompressible flow in a porous channel with expanding or contacting walls in the presence of a transverse magnetic field is considered. Using similarity transformations, the governing equations are reduced to the ... An incompressible flow in a porous channel with expanding or contacting walls in the presence of a transverse magnetic field is considered. Using similarity transformations, the governing equations are reduced to the nonlinear ordinary differential equations. The exact similar solutions for the different cases of the expansion ratio and the Hartmann number are obtained with a singular perturbation method, and the associated behavior is discussed in detail. 展开更多
关键词 porous channel transverse magnetic field expanding or contracting wails
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Achieving reliable and anti-collusive outsourcing computation and verification based on blockchain in 5G-enabled IoT
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作者 Linjie Wang Youliang Tian Jinbo Xiong 《Digital Communications and Networks》 SCIE CSCD 2022年第5期644-653,共10页
Widespread applications of 5G technology have prompted the outsourcing of computation dominated by the Internet of Things(IoT)cloud to improve transmission efficiency,which has created a novel paradigm for improving t... Widespread applications of 5G technology have prompted the outsourcing of computation dominated by the Internet of Things(IoT)cloud to improve transmission efficiency,which has created a novel paradigm for improving the speed of common connected objects in IoT.However,although it makes it easier for ubiquitous resource-constrained equipment that outsources computing tasks to achieve high-speed transmission services,security concerns,such as a lack of reliability and collusion attacks,still exist in the outsourcing computation.In this paper,we propose a reliable,anti-collusion outsourcing computation and verification protocol,which uses distributed storage solutions in response to the issue of centralized storage,leverages homomorphic encryption to deal with outsourcing computation and ensures data privacy.Moreover,we embed outsourcing computation results and a novel polynomial factorization algorithm into the smart contract of Ethereum,which not only enables the verification of the outsourcing result without a trusted third party but also resists collusion attacks.The results of the theoretical analysis and experimental performance evaluation demonstrate that the proposed protocol is secure,reliable,and more effective compared with state-of-the-art approaches. 展开更多
关键词 outsourcing computation Ethereum Smart contract Public verification Homomorphic encryption
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Effect of Knowledge about Workers' Psychological Contract Imbalance on Organizational Performance
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作者 WANG Yongan SUN Minggui 《Journal of Donghua University(English Edition)》 EI CAS 2018年第5期406-410,共5页
Knowledge-based employees are the inexhaustible motive force for the sustainable development of modern enterprises. Being consistent with the psychological expectation of knowledge-based employees is conducive to stim... Knowledge-based employees are the inexhaustible motive force for the sustainable development of modern enterprises. Being consistent with the psychological expectation of knowledge-based employees is conducive to stimulating the intrinsic motivation of knowledge-based employees and promoting the innovation performance of enterprises. Based on 175 valid questionnaires,the analysis shows that the knowledge about employees' psychological contract can be divided into two-dimension, transactional or relational dimension. Both of them are independent to each other.The correlation analysis shows that the transactional psychological contract and relational psychological contract have positive correlation with team performance and organization performance.At the same time, the team performance and organization performance have positive correlation. Regression analysis shows that compared with relational psychological contract,transactional psychological contract can promote team performance and organizational performance more effectively. Both two psychological contracts can mediate the organizational performance by virtue of team performance. 展开更多
关键词 KNOWLEDGE EMPLOYEE PSYCHOLOGICAL CONTRACT PSYCHOLOGICAL IMBALANCE ORGANIZATIONAL performance
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Synthetic Evaluation of Contractor's Performance in Outcome-Based Contract
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作者 王芳 石全 胡志伟 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期201-205,共5页
Outcome-based contract( OBC) is a kind of contracting mechanism,which allows the customer to pay only when the firm has delivered outcomes,rather than activities and tasks involved. To achieve the higher demand of the... Outcome-based contract( OBC) is a kind of contracting mechanism,which allows the customer to pay only when the firm has delivered outcomes,rather than activities and tasks involved. To achieve the higher demand of the delivering outcome of the contract,the evaluation of contractor's performance was focused on. A reasonable and objective contractor performance evaluation system is constructed by considering various uncertainties. The set pair theory is used to analyze the four-element connection of quality of service contractors. It aims to provide a theoretical basis for the decisionmaker to make confirmation of the equipment contractor who has a better performance and development trend. 展开更多
关键词 outcome-based contract(OBC) CONTRACTOR four-element connection PERFORMANCE criteria system
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The Role of the Outsourcing Contract From a Partnership-based Perspective
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作者 Paolo Popoli 《Chinese Business Review》 2017年第6期292-302,共11页
The definition of relational contents which outsourcer and outsourcee arrange and formalize inside a contract is one of the critical success factors of the outsourcing choice. The contract criticality is greater if th... The definition of relational contents which outsourcer and outsourcee arrange and formalize inside a contract is one of the critical success factors of the outsourcing choice. The contract criticality is greater if the outsourcing aim is made of highly strategic activities, functions, or processes and if the real aim is not the cost saving but the sharing of added value resources, skills, and knowledge. That is, this paper aims to provide some conceptual insights about the role of the contract with a specific reference to the strategic outsourcing, which is the kind of outsourcing where the relationship between the outsourcer and outsourcee is set inside the "partnership-based" logic. In particular the remarks proposed concern the role of the contract as a tool to face the risk and manage the relationship. 展开更多
关键词 outsourcing contract contract management partnership-based perspective outsourcing risks
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Use of Innovative Contracting Methods by Dots - Project Managers Speak
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作者 Edward Minchin Ralph D. Ellis +1 位作者 Jae-Ho Pyeon Jichao Zhan 《Journal of Civil Engineering and Architecture》 2010年第8期14-26,共13页
Alternative contracting techniques have been frequently used in highway construction in the United State and have played an important role in the effort to improve construction project performance. However, it is stil... Alternative contracting techniques have been frequently used in highway construction in the United State and have played an important role in the effort to improve construction project performance. However, it is still unknown whether which project factors have significant influence on project performance. It is essential to learn from the experiences and opinions of construction project managers who had executed innovative or alternative contracts in order to improve and refine the usage of alternative contracting methods. Innovative contracting methods have been used by state Departments of Transportation for many years, so there is now sufficient data to measure the effectiveness of these innovations. Working under a grant from the Florida Department of Transportation (FDOT), the research team used the experiences and opinions of construction field engineers who had executed innovative contracts on FDOT projects to measure the effectiveness of these systems. To that end, interviews were conducted with FDOT and consultant personnel from across Florida. All interviewed were project managers who had overseen at least one project using an innovative contracting method. Discussions brought enthusiastic responses from those interviewed, both for and against certain innovations. This paper will focus on the experiences and opinions of those experienced construction field engineers dealing with well-known innovations, as well as newer innovations such as "Detour Rental" and "Damage Recovery". 展开更多
关键词 Alternative contracting highway construction A+B incentive/disincentive DESIGN-BUILD CM-at-Risk.
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Traffic Impact on Incentive Contracting Project Time Performance during Highway Construction
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作者 Jae-Ho Pyeon 《Journal of Civil Engineering and Architecture》 2010年第7期9-14,共6页
The volume of highway traffic in the United States continues to increase. In the face of this there is a concomitant need to improve and repair transportation infrastructure. Construction frequently requires a reducti... The volume of highway traffic in the United States continues to increase. In the face of this there is a concomitant need to improve and repair transportation infrastructure. Construction frequently requires a reduction in capacity during construction activity; consequently road users as well as adjacent businesses must endure the delays and inconveniences associated with transportation construction. Recognizing the problems that construction can produce, state highway agencies (SHAs) have continually sought ways to minimize the negative impact from their construction operations. Incentive contracting has played an important role in this effort to improve project performance. The Florida Department of Transportation (FDOT) is one of the leading SHAs using such innovative contracting methods as Incentive/Disincentive (I/D), A+B (cost plus time bidding) combined with I/D, No Excuse Bonus, and Liquidated Savings. This paper analyzes the traffic impact on incentive project time performance using highway construction projects recently completed in Florida. Project data obtained from FDOT were evaluated using time performance indices. A survey of traffic impact on project work types was performed in Florida in order to evaluate the relationship between construction project types and road traffic influence during construction. Based on the survey results, the 38 most frequently used work types in Florida during the study period were categorized into three traffic impact levels: (1) high traffic impact, (2) medium traffic impact, and (3) low traffic impact. Statistical analysis was performed. The results show that there are significant differences on project time performance between low and high impact levels as well as low and medium impact levels. 展开更多
关键词 Highway construction project performance traffic impact alternative contracting incentive/disincentive
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Myofiber Permeability and Force Production of Rat Muscles Following Eccentric Contractions: The Repeated Bout Effect Depends on the Interval
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作者 Keishi Hayao Hiroyuki Tamaki +2 位作者 Keigo Tamakoshi Hideaki Takahashi Hideaki Onishi 《Journal of Biomedical Science and Engineering》 2020年第12期275-289,共15页
Past eccentric contraction (ECC)-induced muscle injury reduces the severity of symptoms of subsequent muscle injury;this phenomenon is known as a repeated bout effect (RBE). It has been reported that increases in the ... Past eccentric contraction (ECC)-induced muscle injury reduces the severity of symptoms of subsequent muscle injury;this phenomenon is known as a repeated bout effect (RBE). It has been reported that increases in the duration of the interval between the first and second bouts are linked to weakening of the RBE. However, the histology following the attenuation of the RBE remains unclear. We examined the sustained effects of the second bout with regard to myofiber permeability and muscle force. Sixty-four male rats were randomly assigned to eight groups that varied in the number of exercise sessions and the duration of the interval between the first and second bouts: the non-ECC (Control);the single-injury (Post 1st bout);groups that were allowed to recover for 1, 2, and 4 weeks after a single injury (Pre 2nd bout_1w, Pre 2nd bout_2w, and Pre 2nd bout_4w);and groups that were subjected to second injuries 1, 2, and 4 weeks after the first (Post 2nd bout_1w, Post 2nd bout_2w, and Post 2nd bout_4w). The tibialis anterior was electrically stimulated in each ECC group. Twenty-four hours before muscle sampling, Evans blue dye (EBD) (a marker of myofiber damage) was administered. The maximal isometric contraction tension was measured immediately before sampling. The number of EBD-positive (+) fibers was determined via histological analysis. An RBE was revealed by functional examination at the 1- and 2-week and histological examination at the 1-, 2-, and 4-week time points (P < 0.05). In terms of myofiber permeability, prolongation of the interval before the second bout weakened this effect (P < 0.05). Experiments with 1-, 2-, and 4-week intervals indicated that prolongation of the interval before the second bout weakened the RBE with regard to myofiber permeability. 展开更多
关键词 Eccentric Contraction Muscle Injury Repeated Bout Effect Myofiber Membrane Permeability Maximal Isometric Contraction Tension
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