This paper presents a comparative qualitative analysis of reputational crisis of four European banks, and explores how in recent years these companies have faced the manifestation of reputational risk. To achieve this...This paper presents a comparative qualitative analysis of reputational crisis of four European banks, and explores how in recent years these companies have faced the manifestation of reputational risk. To achieve this, the research follows three related steps： （1） to carry out a review of the literature on reputational risk in the banking sector aimed to identify the relationships between causes, effects, stakeholders, and key qualitative-quantitative variables involved during the reputational crisis of a bank; （2） to propose a conceptual framework for management of reputational risk （and reputational crisis） in banking; （3） to test this framework with the results of an empirical analysis, carried out through the observation of key variables of some reputational crisis of intemational banks. The main results show that： （1） the banks are not yet prepared to accurately manage a reputational crisis or to prevent them; （2） the reputational crisis is determined by several internal and external factors; （3） the conduct of the managers and the corporate communication are very important to overcome a reputational crisis. Finally, this research provides indications that will help banks to better manage their corporate reputation and prevent reputational crisis.展开更多
To study the incentive mechanisms of cooperation, we propose a preference rewarding mechanism in the spatial prisoner’s dilemma game, which simultaneously considers reputational preference, other-regarding preference...To study the incentive mechanisms of cooperation, we propose a preference rewarding mechanism in the spatial prisoner’s dilemma game, which simultaneously considers reputational preference, other-regarding preference and the dynamic adjustment of vertex weight. The vertex weight of a player is adaptively adjusted according to the comparison result of his own reputation and the average reputation value of his immediate neighbors. Players are inclined to pay a personal cost to reward the cooperative neighbor with the greatest vertex weight. The vertex weight of a player is proportional to the preference rewards he can obtain from direct neighbors. We find that the preference rewarding mechanism significantly facilitates the evolution of cooperation, and the dynamic adjustment of vertex weight has powerful effect on the emergence of cooperative behavior. To validate multiple effects, strategy distribution and the average payoff and fitness of players are discussed in a microcosmic view.展开更多
Leveraging the principal-agent theory,this study incorporates reputational capital into a continuous-time framework for analyzing venture capital exit decisions.The authors explore how the principal-agent relationship...Leveraging the principal-agent theory,this study incorporates reputational capital into a continuous-time framework for analyzing venture capital exit decisions.The authors explore how the principal-agent relationships influence the decision to take capital public by synthesizing optimal incentive alignment and IPO timing within a unified model.The results uncover an intriguing aspect of reputational capital:Despite entrepreneurial efforts to augment this capital,its growth is not linear but tends to reach the highest level before the IPO event.Furthermore,the accumulation of reputational capital expedites the capital exit process and enhances the returns from such exits.Subsequently,as the exit timeline extends,the proportion of exit returns allocated to entrepreneurs escalates to a full share,imposing a constrained decision window for investors on exit timing.The findings suggest that the timing for maximizing investor returns at an IPO is later than the timing that maximizes company revenue.Moreover,excessive IPO costs further delay this exit decision for investors.These findings offer fresh insights into the languishing IPO market observed over the last two decades.展开更多
This paper considers the supplier investment decision-making problem in a supply chain consisting of an original equipment manufacturer(OEM),a global supplier,and a local supplier.To reduce dependence on global suppli...This paper considers the supplier investment decision-making problem in a supply chain consisting of an original equipment manufacturer(OEM),a global supplier,and a local supplier.To reduce dependence on global suppliers and improve supply stability,we develop a differential game model to investigate the optimal investment decisions of the OEM towards the local supplier under different risk scenarios and the impact of different risks on the optimal decisions.The results show that investment efficiency and risks have a significant impact on OEM investment decisions.Specifically,when the OEM has higher investment efficiency,investing in the local supplier is profitable for the OEM;conversely,when the investment efficiency of the OEM is lower,it does not invest.In addition,an increase in the supply risk of the global supplier will lower the entry threshold for OEM investment,but an increase in the supply risk of the local supplier and the reputational risk of both will increase this threshold,meaning that only the OEM with significantly higher investment efficiency can profit.展开更多
Practical byzantine fault tolerance(PBFT)can reduce energy consumption and achieve high throughput compared with the traditional PoW algorithm,which is more suitable for a strongly consistent consortium blockchain.How...Practical byzantine fault tolerance(PBFT)can reduce energy consumption and achieve high throughput compared with the traditional PoW algorithm,which is more suitable for a strongly consistent consortium blockchain.However,due to the frequent communication among nodes,PBFT cannot realize scalability in large-scale networks.Existing PBFTbased algorithms still ignore performance and security.Therefore,we propose a secure and efficient practical byzantine fault tolerance based on double layers and multi copies(DM-PBFT).We design a reputation evaluation and node scheduling method for DMPBFT.And then we propose an adaptive node scheduling strategy based on the derived threshold values after analyzing the system communication complexity and security.Combining the above research,a node dynamic adjustment mechanism is proposed to freeze or adjust the node operation status according to the system environment.Simulation experiments show that the proposed mechanism can improve efficiency and increase the system’s throughput.展开更多
V2X communication enables vehicles to share real-time traffic and road-condition data,but binding messages to persistent identifiers enables location tracking.Furthermore,since forged reports from malicious vehicles c...V2X communication enables vehicles to share real-time traffic and road-condition data,but binding messages to persistent identifiers enables location tracking.Furthermore,since forged reports from malicious vehicles can distort trust decisions and threaten road safety,privacy-preserving trust management is essential.Lu et al.previously presented BARS,an anonymous reputation mechanism founded on blockchain technology to establish a privacy-preserving trust architecture for V2X communication.In this system,reputation certificates without a vehicle identifier ensure anonymity,while two authorities jointly manage certificate issuance and reputation updates.However,the centralized certificate updates introduce scalability limitations,and the authorities can trace vehicle behavioral information,which threatens privacy guarantees.Several subsequent systems derived from BARS still rely on centralized certificate management and are subject to authority-side privacy leakage.As a result,a key challenge in this line of research remains unresolved:how to decentralize the certificate-update process while preserving privacy against the authorities in privacy-preservingV2X trustmanagement.In this paper,we propose a distributed anonymous reputation system for V2X communication,based on an anonymous reputation system for crowdsensing.In our proposed system for V2X communication,the server is distributed to a certificate authority(CA)and roadside units(RSUs).Each vehicle shows the reputation level to the nearest RSU at the beginning of each time interval,and registers a short-time public key.In the interval,the messages from the vehicle are authenticated under the public key and are scored.At the end of the interval,the nearest RSU updates the certificate anonymously.Our solution decentralizes the certificate-update process by assigning each update to the nearest RSU.A zero-knowledge-proof-based show protocol removes the need for any central authority to handle vehicle certificates and thus prevents the authorities from tracing vehicle activities.Compared with BARS,where centralized authorities must update the reputation certificates of many vehicles and may incur communication and processing delays,our system performs each update locally at the nearest RSUonce per interval.The required interaction consists only of a fewkilobytes of communication and a zero-knowledge proof that is almost fully precomputed on the vehicle side,while the RSU-side processing is estimated to take about 40 ms based on timingmeasurements of the underlying cryptographic operations.This distributed updatemodel avoids the centralized bottleneck of BARS and simultaneously removes the privacy risk arising from authority collusion.展开更多
Purpose:For a set of 1,561 Open Access(OA)and non-OA journals in business and economics,this study evaluates the relationships between four citation metrics-five-year Impact Factor(5IF),CiteScore,Article Influence(AI)...Purpose:For a set of 1,561 Open Access(OA)and non-OA journals in business and economics,this study evaluates the relationships between four citation metrics-five-year Impact Factor(5IF),CiteScore,Article Influence(AI)score,and SCImago Journal Rank(SJR)-and the journal ratings assigned by expert reviewers.We expect that the OA journals will have especially high citation impact relative to their perceived quality(reputation).Design/methodology/approach:Regression is used to estimate the ratings assigned by expert reviewers for the 2021 CABS(Chartered Association of Business Schools)journal assessment exercise.The independent variables are the four citation metrics,evaluated separately,and a dummy variable representing the OA/non-OA status of each journal.Findings:Regardless of the citation metric used,OA journals in business and economics have especially high citation impact relative to their perceived quality(reputation).That is,they have especially low perceived quality(reputation)relative to their citation impact.Research limitations:These results are specific to the CABS journal ratings and the four citation metrics.However,there is strong evidence that CABS is closely related to several other expert ratings,and that 5IF,CiteScore,AI,and SJR are representative of the other citation metrics that might have been chosen.Practical implications:There are at least two possible explanations for these results:(1)expert evaluators are biased against OA journals,and(2)OA journals have especially high citation impact due to their increased accessibility.Although this study does not allow us to determine which of these explanations are supported,the results suggest that authors should consider publishing in OA journals whenever overall readership and citation impact are more important than journal reputation within a particular field.Moreover,the OA coefficients provide a useful indicator of the extent to which anti-OA bias(or the citation advantage of OA journals)is diminishing over time.Originality/value:This is apparently the first study to investigate the impact of OA status on the relationships between expert journal ratings and journal citation metrics.展开更多
Blockchain-based user-centric access network(UCAN)fails in dynamic access point(AP)management,as it lacks an incentive mechanism to promote virtuous behavior.Furthermore,the low throughput of the blockchain has been a...Blockchain-based user-centric access network(UCAN)fails in dynamic access point(AP)management,as it lacks an incentive mechanism to promote virtuous behavior.Furthermore,the low throughput of the blockchain has been a bottleneck to the widespread adoption of UCAN in 6G.In this paper,we propose Overlap Shard,a blockchain framework based on a novel reputation voting(RV)scheme,to dynamically manage the APs in UCAN.AP nodes in UCAN are distributed across multiple shards based on the RV scheme.That is,nodes with good reputation(virtuous behavior)are likely to be selected in the overlap shard.The RV mechanism ensures the security of UCAN because most APs adopt virtuous behaviors.Furthermore,to improve the efficiency of the Overlap Shard,we reduce cross-shard transactions by introducing core nodes.Specifically,a few nodes are overlapped in different shards,which can directly process the transactions in two shards instead of crossshard transactions.This greatly increases the speed of transactions between shards and thus the throughput of the overlap shard.The experiments show that the throughput of the overlap shard is about 2.5 times that of the non-sharded blockchain.展开更多
In response to the challenges presented by the unreliable identity of the master node,high communication overhead,and limited network support size within the Practical Byzantine Fault-Tolerant(PBFT)algorithm for conso...In response to the challenges presented by the unreliable identity of the master node,high communication overhead,and limited network support size within the Practical Byzantine Fault-Tolerant(PBFT)algorithm for consortium chains,we propose an improved PBFT algorithm based on XGBoost grouping called XG-PBFT in this paper.XG-PBFT constructs a dataset by training important parameters that affect node performance,which are used as classification indexes for nodes.The XGBoost algorithm then is employed to train the dataset,and nodes joining the system will be grouped according to the trained grouping model.Among them,the nodes with higher parameter indexes will be assigned to the consensus group to participate in the consensus,and the rest of the nodes will be assigned to the general group to receive the consensus results.In order to reduce the resource waste of the system,XG-PBFT optimizes the consensus protocol for the problem of high complexity of PBFT communication.Finally,we evaluate the performance of XG-PBFT.The experimental results show that XG-PBFT can significantly improve the performance of throughput,consensus delay and communication complexity compared to the original PBFT algorithm,and the performance enhancement is significant compared to other algorithms in the case of a larger number of nodes.The results demonstrate that the XG-PBFT algorithm is more suitable for large-scale consortium chains.展开更多
Taking China’s 2018 value-added tax(VAT)credit refund reform as an exogenous shock to improve VAT neutrality,we use a difference-in-differences approach to explore how the reform affected corporate social responsibil...Taking China’s 2018 value-added tax(VAT)credit refund reform as an exogenous shock to improve VAT neutrality,we use a difference-in-differences approach to explore how the reform affected corporate social responsibility(CSR).We find that the reform motivated firms to improve CSR performance.The reform has a“resource”effect,increasing internal funds and reducing financing costs,thereby enhancing firms’ability to undertake CSR.The reform also has a“reputation”effect,stimulating firms’willingness to engage in CSR to improve their reputations.CSR following the reform increases firm values and reduces bankruptcy risk.Our study provides fresh insights into VAT neutrality theory and is a reference for tax reform in emerging economies.展开更多
With the development of vehicle networks and the construction of roadside units,Vehicular Ad Hoc Networks(VANETs)are increasingly promoting cooperative computing patterns among vehicles.Vehicular edge computing(VEC)of...With the development of vehicle networks and the construction of roadside units,Vehicular Ad Hoc Networks(VANETs)are increasingly promoting cooperative computing patterns among vehicles.Vehicular edge computing(VEC)offers an effective solution to mitigate resource constraints by enabling task offloading to edge cloud infrastructure,thereby reducing the computational burden on connected vehicles.However,this sharing-based and distributed computing paradigm necessitates ensuring the credibility and reliability of various computation nodes.Existing vehicular edge computing platforms have not adequately considered themisbehavior of vehicles.We propose a practical task offloading algorithm based on reputation assessment to address the task offloading problem in vehicular edge computing under an unreliable environment.This approach integrates deep reinforcement learning and reputation management to address task offloading challenges.Simulation experiments conducted using Veins demonstrate the feasibility and effectiveness of the proposed method.展开更多
Aim To study the implicit restriction mechanism for hidden action in multi stage dynamic game. Methods A reputation model for restriction on repeated principal agent relationship was established by using the theor...Aim To study the implicit restriction mechanism for hidden action in multi stage dynamic game. Methods A reputation model for restriction on repeated principal agent relationship was established by using the theory on principal agent problem in information economics and the method of game theory to study the implicit restriction mechanism for hidden action. Results and Conclusion It is proved that there exists implicit restriction mechanism for the multi stage principal agent relationship, some conditions for effective restriction are derived, the design methods of implicit restriction mechanism are presented.展开更多
Is He Living or Is He Dead is mainly about an outstanding painter Francois Millet who pretend to be dead in order to get reputation and money,because at that time a great artist has never been acknowledged until after...Is He Living or Is He Dead is mainly about an outstanding painter Francois Millet who pretend to be dead in order to get reputation and money,because at that time a great artist has never been acknowledged until after he was starved and dead. Based on the critic approach of New Historicism, this thesis have analyzed how Millet subvert power and be contained by power, the capitalism and market, which criticized the phenomenon that the value of art is not decided by itself, but by power. No matter it is good or bad, if it is denied by power, it is valueless.展开更多
This contribution deals with a generative approach for the analysis of textual data. Instead of creating heuristic rules forthe representation of documents and word counts, we employ a distribution able to model words...This contribution deals with a generative approach for the analysis of textual data. Instead of creating heuristic rules forthe representation of documents and word counts, we employ a distribution able to model words along texts considering different topics. In this regard, following Minka proposal (2003), we implement a Dirichlet Compound Multinomial (DCM) distribution, then we propose an extension called sbDCM that takes explicitly into account the different latent topics that compound the document. We follow two alternative approaches: on one hand the topics can be unknown, thus to be estimated on the basis of the data, on the other hand topics are determined in advance on the basis of a predefined ontological schema. The two possible approaches are assessed on the basis of real data.展开更多
Bitcoin has a bad reputation.The decentralised digital cryptocurrency,powered by a vast computer network,is notorious for the wild fluctuations in its value,the zeal of its supporters and its degenerate uses,such as e...Bitcoin has a bad reputation.The decentralised digital cryptocurrency,powered by a vast computer network,is notorious for the wild fluctuations in its value,the zeal of its supporters and its degenerate uses,such as extortion,buying drugs and hiring hitmen in the online bazaars of the'dark net'.比特币有一个坏名声。这种由一个庞大的计算机网络来驱动的去中心化数字加密货币,其恶名源于币值的剧烈波动、支持者的狂热追捧以及各种堕落的用途,如敲诈勒索、购买毒品和在'暗网'的在线市场雇佣杀手等。展开更多
As an emerging distributed technology, blockchain has begun to penetrate into many fields such as finance, healthcare, supply chain, intelligent transportation. However, the interoperability and value exchange between...As an emerging distributed technology, blockchain has begun to penetrate into many fields such as finance, healthcare, supply chain, intelligent transportation. However, the interoperability and value exchange between different independent blockchain systems is restricting the expansion of blockchain. In this paper, a notary group-based cross-chain interaction model is proposed to achieve the interoperability between different blockchains. Firstly, a notary election mechanism is proposed to choose one notary from the notary group to act as a bridge for cross-chain transactions. Secondly, a margin pool is introduced to limit the misconduct of the elected notary and ensure the value transfer between the involved blockchains. Moreover, a reputation based incentive mechanism is used to encourage members of the notary group to participate in cross-chain transactions. Ethereum-based experiments demonstrate that the proposed mechanism can provide an acceptable performance for cross-chain transactions and provide a higher security level than ordinary cross-chain mechanisms.展开更多
MANET routing is critical and routing decision should be made sooner before the node leaves the network.Fast decisions always compensate network performance.In addition,most MANET routing protocols assume a friendly a...MANET routing is critical and routing decision should be made sooner before the node leaves the network.Fast decisions always compensate network performance.In addition,most MANET routing protocols assume a friendly and cooperative environment,and hence are vulnerable to various attacks.Trust and Reputation would serve as a major solution to these problems.Learning the network characteristics and choosing right routing decisions at right times would be a significant solution.In this work,we have done an extensive survey of fault tolerant protocols and ant colony algorithms applied to routing in MANETs.We propose a QoS constrained fault tolerant ant lookahead routing algorithm which attempts to identify valid route and look-ahead route pairs which might help in choosing the alternate path in case of valid route failure.The results prove that the proposed algorithm takes better routing decisions with 20-30 percent improvement compared with existing ant colony algorithms.展开更多
A Service Level Agreement(SLA) is a legal contract between any two parties to ensure an adequate Quality of Service(Qo S). Most research on SLAs has concentrated on protecting the user data through encryption. However...A Service Level Agreement(SLA) is a legal contract between any two parties to ensure an adequate Quality of Service(Qo S). Most research on SLAs has concentrated on protecting the user data through encryption. However, these methods can not supervise a cloud service provider(CSP) directly. In order to address this problem, we propose a privacy-based SLA violation detection model for cloud computing based on Markov decision process theory. This model can recognize and regulate CSP's actions based on specific requirements of various users. Additionally, the model could make effective evaluation to the credibility of CSP, and can monitor events that user privacy is violated. Experiments and analysis indicate that the violation detection model can achieve good results in both the algorithm's convergence and prediction effect.展开更多
Wireless Mesh Networks （WMNs） are vulnerable to various security threats because of their special infrastructure and communication mode, wherein insider attacks are the most challenging issue. To address this proble...Wireless Mesh Networks （WMNs） are vulnerable to various security threats because of their special infrastructure and communication mode, wherein insider attacks are the most challenging issue. To address this problem and protect innocent users from malicious attacks, it is important to encourage cooperation and deter malicious behaviors. Reputation systems constitute a major category of techniques used for managing trust in distributed networks, and they are effective in characterizing and quantifying a node＇s behavior for WMNs. However, conventional layered reputation mechanisms ignore several key factors of reputation in other layers; therefore, they cannot provide optimal performance and accurate malicious node identification and isolation for WMNs. In this paper, we propose a novel dynamic reputation mechanism, SLCRM, which couples reputation systems with a cross-layer design and node-security-rating classification techniques to dynamically detect and restrict insider attacks. Simulation results show that in terms of network throughput, packet delivery ratio, malicious nodes＇ identification, and success rates, SI_CRM imple- ments security protection against insider attacks in a more dynamic, effective, and efficient manner than the subjective logic and uncertainty-based reputation model and the familiarity-based reputation model.展开更多
Volunteered geographic information(VGI)has entered a phase where there are both a substantial amount of crowdsourced information available and a big interest in using it by organizations.But the issue of deciding the ...Volunteered geographic information(VGI)has entered a phase where there are both a substantial amount of crowdsourced information available and a big interest in using it by organizations.But the issue of deciding the quality of VGI without resorting to a comparison with authoritative data remains an open challenge.This article first formulates the problem of quality assessment of VGI data.Then presents a model to measure trustworthiness of information and reputation of contributors by analyzing geometric,qualitative,and semantic aspects of edits over time.An implementation of the model is running on a small data-set for a preliminary empirical validation.The results indicate that the computed trustworthiness provides a valid approximation of VGI quality.展开更多
文摘This paper presents a comparative qualitative analysis of reputational crisis of four European banks, and explores how in recent years these companies have faced the manifestation of reputational risk. To achieve this, the research follows three related steps： （1） to carry out a review of the literature on reputational risk in the banking sector aimed to identify the relationships between causes, effects, stakeholders, and key qualitative-quantitative variables involved during the reputational crisis of a bank; （2） to propose a conceptual framework for management of reputational risk （and reputational crisis） in banking; （3） to test this framework with the results of an empirical analysis, carried out through the observation of key variables of some reputational crisis of intemational banks. The main results show that： （1） the banks are not yet prepared to accurately manage a reputational crisis or to prevent them; （2） the reputational crisis is determined by several internal and external factors; （3） the conduct of the managers and the corporate communication are very important to overcome a reputational crisis. Finally, this research provides indications that will help banks to better manage their corporate reputation and prevent reputational crisis.
基金the National Natural Science Foundation of China(Grant No.62062049)the Social Science Project of the Ministry of Education of China(Grant No.20YJCZH212)the Natural Science Foundation of Gansu Province,China(Grant No.20JR5RA390).
文摘To study the incentive mechanisms of cooperation, we propose a preference rewarding mechanism in the spatial prisoner’s dilemma game, which simultaneously considers reputational preference, other-regarding preference and the dynamic adjustment of vertex weight. The vertex weight of a player is adaptively adjusted according to the comparison result of his own reputation and the average reputation value of his immediate neighbors. Players are inclined to pay a personal cost to reward the cooperative neighbor with the greatest vertex weight. The vertex weight of a player is proportional to the preference rewards he can obtain from direct neighbors. We find that the preference rewarding mechanism significantly facilitates the evolution of cooperation, and the dynamic adjustment of vertex weight has powerful effect on the emergence of cooperative behavior. To validate multiple effects, strategy distribution and the average payoff and fitness of players are discussed in a microcosmic view.
基金supported by the National Natural Science Foundation of China under Grant Nos.72401001,72188101 and 72271080Scientific Research Projects of Anhui Province under Grant Nos.2022AH050104,2022AH050035+2 种基金Anhui Province Social Science Innovation Development Research Project under Grant No.2023CX056Double First-Class Discipline Construction Project under Grant No.PA2024GDGP0032The Fundamental Research Funds for the Central Universities of China under Grant No.PA2024GDSK0110。
文摘Leveraging the principal-agent theory,this study incorporates reputational capital into a continuous-time framework for analyzing venture capital exit decisions.The authors explore how the principal-agent relationships influence the decision to take capital public by synthesizing optimal incentive alignment and IPO timing within a unified model.The results uncover an intriguing aspect of reputational capital:Despite entrepreneurial efforts to augment this capital,its growth is not linear but tends to reach the highest level before the IPO event.Furthermore,the accumulation of reputational capital expedites the capital exit process and enhances the returns from such exits.Subsequently,as the exit timeline extends,the proportion of exit returns allocated to entrepreneurs escalates to a full share,imposing a constrained decision window for investors on exit timing.The findings suggest that the timing for maximizing investor returns at an IPO is later than the timing that maximizes company revenue.Moreover,excessive IPO costs further delay this exit decision for investors.These findings offer fresh insights into the languishing IPO market observed over the last two decades.
基金supported in part by the National Natural Science Foundation of China(NSFC)under Grant No.72271208the China Postdoctoral Science Foundation under Grant No.2023M741907.
文摘This paper considers the supplier investment decision-making problem in a supply chain consisting of an original equipment manufacturer(OEM),a global supplier,and a local supplier.To reduce dependence on global suppliers and improve supply stability,we develop a differential game model to investigate the optimal investment decisions of the OEM towards the local supplier under different risk scenarios and the impact of different risks on the optimal decisions.The results show that investment efficiency and risks have a significant impact on OEM investment decisions.Specifically,when the OEM has higher investment efficiency,investing in the local supplier is profitable for the OEM;conversely,when the investment efficiency of the OEM is lower,it does not invest.In addition,an increase in the supply risk of the global supplier will lower the entry threshold for OEM investment,but an increase in the supply risk of the local supplier and the reputational risk of both will increase this threshold,meaning that only the OEM with significantly higher investment efficiency can profit.
基金supported in part by Beijing Natural Science Foundation(L244010,251038)National Natural Science Foundation of China(92467203,62372050,62502041)+2 种基金CCF-Huawei Populus Grove Fund(TC202418)Fellowship of China National Postdoctoral Program for Innovative Talents(BX20240045)China Postdoctoral Science Foundation General Program(2025M773481).
文摘Practical byzantine fault tolerance(PBFT)can reduce energy consumption and achieve high throughput compared with the traditional PoW algorithm,which is more suitable for a strongly consistent consortium blockchain.However,due to the frequent communication among nodes,PBFT cannot realize scalability in large-scale networks.Existing PBFTbased algorithms still ignore performance and security.Therefore,we propose a secure and efficient practical byzantine fault tolerance based on double layers and multi copies(DM-PBFT).We design a reputation evaluation and node scheduling method for DMPBFT.And then we propose an adaptive node scheduling strategy based on the derived threshold values after analyzing the system communication complexity and security.Combining the above research,a node dynamic adjustment mechanism is proposed to freeze or adjust the node operation status according to the system environment.Simulation experiments show that the proposed mechanism can improve efficiency and increase the system’s throughput.
文摘V2X communication enables vehicles to share real-time traffic and road-condition data,but binding messages to persistent identifiers enables location tracking.Furthermore,since forged reports from malicious vehicles can distort trust decisions and threaten road safety,privacy-preserving trust management is essential.Lu et al.previously presented BARS,an anonymous reputation mechanism founded on blockchain technology to establish a privacy-preserving trust architecture for V2X communication.In this system,reputation certificates without a vehicle identifier ensure anonymity,while two authorities jointly manage certificate issuance and reputation updates.However,the centralized certificate updates introduce scalability limitations,and the authorities can trace vehicle behavioral information,which threatens privacy guarantees.Several subsequent systems derived from BARS still rely on centralized certificate management and are subject to authority-side privacy leakage.As a result,a key challenge in this line of research remains unresolved:how to decentralize the certificate-update process while preserving privacy against the authorities in privacy-preservingV2X trustmanagement.In this paper,we propose a distributed anonymous reputation system for V2X communication,based on an anonymous reputation system for crowdsensing.In our proposed system for V2X communication,the server is distributed to a certificate authority(CA)and roadside units(RSUs).Each vehicle shows the reputation level to the nearest RSU at the beginning of each time interval,and registers a short-time public key.In the interval,the messages from the vehicle are authenticated under the public key and are scored.At the end of the interval,the nearest RSU updates the certificate anonymously.Our solution decentralizes the certificate-update process by assigning each update to the nearest RSU.A zero-knowledge-proof-based show protocol removes the need for any central authority to handle vehicle certificates and thus prevents the authorities from tracing vehicle activities.Compared with BARS,where centralized authorities must update the reputation certificates of many vehicles and may incur communication and processing delays,our system performs each update locally at the nearest RSUonce per interval.The required interaction consists only of a fewkilobytes of communication and a zero-knowledge proof that is almost fully precomputed on the vehicle side,while the RSU-side processing is estimated to take about 40 ms based on timingmeasurements of the underlying cryptographic operations.This distributed updatemodel avoids the centralized bottleneck of BARS and simultaneously removes the privacy risk arising from authority collusion.
文摘Purpose:For a set of 1,561 Open Access(OA)and non-OA journals in business and economics,this study evaluates the relationships between four citation metrics-five-year Impact Factor(5IF),CiteScore,Article Influence(AI)score,and SCImago Journal Rank(SJR)-and the journal ratings assigned by expert reviewers.We expect that the OA journals will have especially high citation impact relative to their perceived quality(reputation).Design/methodology/approach:Regression is used to estimate the ratings assigned by expert reviewers for the 2021 CABS(Chartered Association of Business Schools)journal assessment exercise.The independent variables are the four citation metrics,evaluated separately,and a dummy variable representing the OA/non-OA status of each journal.Findings:Regardless of the citation metric used,OA journals in business and economics have especially high citation impact relative to their perceived quality(reputation).That is,they have especially low perceived quality(reputation)relative to their citation impact.Research limitations:These results are specific to the CABS journal ratings and the four citation metrics.However,there is strong evidence that CABS is closely related to several other expert ratings,and that 5IF,CiteScore,AI,and SJR are representative of the other citation metrics that might have been chosen.Practical implications:There are at least two possible explanations for these results:(1)expert evaluators are biased against OA journals,and(2)OA journals have especially high citation impact due to their increased accessibility.Although this study does not allow us to determine which of these explanations are supported,the results suggest that authors should consider publishing in OA journals whenever overall readership and citation impact are more important than journal reputation within a particular field.Moreover,the OA coefficients provide a useful indicator of the extent to which anti-OA bias(or the citation advantage of OA journals)is diminishing over time.Originality/value:This is apparently the first study to investigate the impact of OA status on the relationships between expert journal ratings and journal citation metrics.
基金supported by the National Natural Science Foundation of China(NSFC)under Grant 61931005.
文摘Blockchain-based user-centric access network(UCAN)fails in dynamic access point(AP)management,as it lacks an incentive mechanism to promote virtuous behavior.Furthermore,the low throughput of the blockchain has been a bottleneck to the widespread adoption of UCAN in 6G.In this paper,we propose Overlap Shard,a blockchain framework based on a novel reputation voting(RV)scheme,to dynamically manage the APs in UCAN.AP nodes in UCAN are distributed across multiple shards based on the RV scheme.That is,nodes with good reputation(virtuous behavior)are likely to be selected in the overlap shard.The RV mechanism ensures the security of UCAN because most APs adopt virtuous behaviors.Furthermore,to improve the efficiency of the Overlap Shard,we reduce cross-shard transactions by introducing core nodes.Specifically,a few nodes are overlapped in different shards,which can directly process the transactions in two shards instead of crossshard transactions.This greatly increases the speed of transactions between shards and thus the throughput of the overlap shard.The experiments show that the throughput of the overlap shard is about 2.5 times that of the non-sharded blockchain.
文摘In response to the challenges presented by the unreliable identity of the master node,high communication overhead,and limited network support size within the Practical Byzantine Fault-Tolerant(PBFT)algorithm for consortium chains,we propose an improved PBFT algorithm based on XGBoost grouping called XG-PBFT in this paper.XG-PBFT constructs a dataset by training important parameters that affect node performance,which are used as classification indexes for nodes.The XGBoost algorithm then is employed to train the dataset,and nodes joining the system will be grouped according to the trained grouping model.Among them,the nodes with higher parameter indexes will be assigned to the consensus group to participate in the consensus,and the rest of the nodes will be assigned to the general group to receive the consensus results.In order to reduce the resource waste of the system,XG-PBFT optimizes the consensus protocol for the problem of high complexity of PBFT communication.Finally,we evaluate the performance of XG-PBFT.The experimental results show that XG-PBFT can significantly improve the performance of throughput,consensus delay and communication complexity compared to the original PBFT algorithm,and the performance enhancement is significant compared to other algorithms in the case of a larger number of nodes.The results demonstrate that the XG-PBFT algorithm is more suitable for large-scale consortium chains.
基金Scientific Research Project of Higher Education Institutions in Hebei Province in 2025“Research on Government Procurement-Driven Green Governance of Hebei’s Manufacturing Industry”(Project No.:QN2025662)Social Science Fund of Hebei Province in 2024“Research on Informal Environmental Regulation Promoting Green Development of Hebei’s Manufacturing Industry”(Project No.:HB24GL036)Hebei Provincial Social Science Development Research Project,“Study on the Constraints and Implementation Paths of the Transformation from Dual Control of Energy Consumption to Dual Control of Carbon Emissions in Hebei Province”(Project No.:HBSKFZ25QN199)。
文摘Taking China’s 2018 value-added tax(VAT)credit refund reform as an exogenous shock to improve VAT neutrality,we use a difference-in-differences approach to explore how the reform affected corporate social responsibility(CSR).We find that the reform motivated firms to improve CSR performance.The reform has a“resource”effect,increasing internal funds and reducing financing costs,thereby enhancing firms’ability to undertake CSR.The reform also has a“reputation”effect,stimulating firms’willingness to engage in CSR to improve their reputations.CSR following the reform increases firm values and reduces bankruptcy risk.Our study provides fresh insights into VAT neutrality theory and is a reference for tax reform in emerging economies.
基金supported by the Open Foundation of Henan Key Laboratory of Cyberspace Situation Awareness(No.HNTS2022020)the Science and Technology Research Program of Henan Province of China(232102210134,182102210130)Key Research Projects of Henan Provincial Universities(25B520005).
文摘With the development of vehicle networks and the construction of roadside units,Vehicular Ad Hoc Networks(VANETs)are increasingly promoting cooperative computing patterns among vehicles.Vehicular edge computing(VEC)offers an effective solution to mitigate resource constraints by enabling task offloading to edge cloud infrastructure,thereby reducing the computational burden on connected vehicles.However,this sharing-based and distributed computing paradigm necessitates ensuring the credibility and reliability of various computation nodes.Existing vehicular edge computing platforms have not adequately considered themisbehavior of vehicles.We propose a practical task offloading algorithm based on reputation assessment to address the task offloading problem in vehicular edge computing under an unreliable environment.This approach integrates deep reinforcement learning and reputation management to address task offloading challenges.Simulation experiments conducted using Veins demonstrate the feasibility and effectiveness of the proposed method.
文摘Aim To study the implicit restriction mechanism for hidden action in multi stage dynamic game. Methods A reputation model for restriction on repeated principal agent relationship was established by using the theory on principal agent problem in information economics and the method of game theory to study the implicit restriction mechanism for hidden action. Results and Conclusion It is proved that there exists implicit restriction mechanism for the multi stage principal agent relationship, some conditions for effective restriction are derived, the design methods of implicit restriction mechanism are presented.
文摘Is He Living or Is He Dead is mainly about an outstanding painter Francois Millet who pretend to be dead in order to get reputation and money,because at that time a great artist has never been acknowledged until after he was starved and dead. Based on the critic approach of New Historicism, this thesis have analyzed how Millet subvert power and be contained by power, the capitalism and market, which criticized the phenomenon that the value of art is not decided by itself, but by power. No matter it is good or bad, if it is denied by power, it is valueless.
文摘This contribution deals with a generative approach for the analysis of textual data. Instead of creating heuristic rules forthe representation of documents and word counts, we employ a distribution able to model words along texts considering different topics. In this regard, following Minka proposal (2003), we implement a Dirichlet Compound Multinomial (DCM) distribution, then we propose an extension called sbDCM that takes explicitly into account the different latent topics that compound the document. We follow two alternative approaches: on one hand the topics can be unknown, thus to be estimated on the basis of the data, on the other hand topics are determined in advance on the basis of a predefined ontological schema. The two possible approaches are assessed on the basis of real data.
文摘Bitcoin has a bad reputation.The decentralised digital cryptocurrency,powered by a vast computer network,is notorious for the wild fluctuations in its value,the zeal of its supporters and its degenerate uses,such as extortion,buying drugs and hiring hitmen in the online bazaars of the'dark net'.比特币有一个坏名声。这种由一个庞大的计算机网络来驱动的去中心化数字加密货币,其恶名源于币值的剧烈波动、支持者的狂热追捧以及各种堕落的用途,如敲诈勒索、购买毒品和在'暗网'的在线市场雇佣杀手等。
基金supported by the National Natural Science Foundation of China (Nos. 61903056 and 61702066)the Chongqing Research Program of Basic Research and Frontier Technology (No. cstc2019jcyj-msxmX0681).
文摘As an emerging distributed technology, blockchain has begun to penetrate into many fields such as finance, healthcare, supply chain, intelligent transportation. However, the interoperability and value exchange between different independent blockchain systems is restricting the expansion of blockchain. In this paper, a notary group-based cross-chain interaction model is proposed to achieve the interoperability between different blockchains. Firstly, a notary election mechanism is proposed to choose one notary from the notary group to act as a bridge for cross-chain transactions. Secondly, a margin pool is introduced to limit the misconduct of the elected notary and ensure the value transfer between the involved blockchains. Moreover, a reputation based incentive mechanism is used to encourage members of the notary group to participate in cross-chain transactions. Ethereum-based experiments demonstrate that the proposed mechanism can provide an acceptable performance for cross-chain transactions and provide a higher security level than ordinary cross-chain mechanisms.
文摘MANET routing is critical and routing decision should be made sooner before the node leaves the network.Fast decisions always compensate network performance.In addition,most MANET routing protocols assume a friendly and cooperative environment,and hence are vulnerable to various attacks.Trust and Reputation would serve as a major solution to these problems.Learning the network characteristics and choosing right routing decisions at right times would be a significant solution.In this work,we have done an extensive survey of fault tolerant protocols and ant colony algorithms applied to routing in MANETs.We propose a QoS constrained fault tolerant ant lookahead routing algorithm which attempts to identify valid route and look-ahead route pairs which might help in choosing the alternate path in case of valid route failure.The results prove that the proposed algorithm takes better routing decisions with 20-30 percent improvement compared with existing ant colony algorithms.
基金supported in part by National Natural Science Foundation of China (NSFC) under Grant U1509219 and 2017YFB0802900
文摘A Service Level Agreement(SLA) is a legal contract between any two parties to ensure an adequate Quality of Service(Qo S). Most research on SLAs has concentrated on protecting the user data through encryption. However, these methods can not supervise a cloud service provider(CSP) directly. In order to address this problem, we propose a privacy-based SLA violation detection model for cloud computing based on Markov decision process theory. This model can recognize and regulate CSP's actions based on specific requirements of various users. Additionally, the model could make effective evaluation to the credibility of CSP, and can monitor events that user privacy is violated. Experiments and analysis indicate that the violation detection model can achieve good results in both the algorithm's convergence and prediction effect.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University under Grant No.IRT1078the Key Program of NSFC-Guangdong Union Foundation under Grant No.U1135002+1 种基金Major National S&T Program under Grant No.2011ZX03005-002the Fundamental Research Funds for the Central Universities under Grant No.JY10000903001
文摘Wireless Mesh Networks （WMNs） are vulnerable to various security threats because of their special infrastructure and communication mode, wherein insider attacks are the most challenging issue. To address this problem and protect innocent users from malicious attacks, it is important to encourage cooperation and deter malicious behaviors. Reputation systems constitute a major category of techniques used for managing trust in distributed networks, and they are effective in characterizing and quantifying a node＇s behavior for WMNs. However, conventional layered reputation mechanisms ignore several key factors of reputation in other layers; therefore, they cannot provide optimal performance and accurate malicious node identification and isolation for WMNs. In this paper, we propose a novel dynamic reputation mechanism, SLCRM, which couples reputation systems with a cross-layer design and node-security-rating classification techniques to dynamically detect and restrict insider attacks. Simulation results show that in terms of network throughput, packet delivery ratio, malicious nodes＇ identification, and success rates, SI_CRM imple- ments security protection against insider attacks in a more dynamic, effective, and efficient manner than the subjective logic and uncertainty-based reputation model and the familiarity-based reputation model.
文摘Volunteered geographic information(VGI)has entered a phase where there are both a substantial amount of crowdsourced information available and a big interest in using it by organizations.But the issue of deciding the quality of VGI without resorting to a comparison with authoritative data remains an open challenge.This article first formulates the problem of quality assessment of VGI data.Then presents a model to measure trustworthiness of information and reputation of contributors by analyzing geometric,qualitative,and semantic aspects of edits over time.An implementation of the model is running on a small data-set for a preliminary empirical validation.The results indicate that the computed trustworthiness provides a valid approximation of VGI quality.
