Wireless sensor networks (WSNs) are ad hoc and self-configuring networks having the possibility that any sensor node can connect or leave the network. With no central controller in WSN, wireless sensor nodes are considered responsible for data routing in the networks. The wireless sensor nodes are very small in size and have limited resources, therefore, it becomes difficult to recharge or replace the battery of the sensor nodes at far places. The present study focused on reducing the battery consumption of the sensor nodes by the deployment of the newly proposed Fault Tolerance Multipath Routing Protocol (MRP-FT) as compared with the existing Low Energy Adaptive Clustering Hierarchy (LEACH) protocol under particle swarm optimisation based fault tolerant routing (PSO-FT) technique. The proposed algorithm of MRP-FT-based on the dynamic clustering technique using Boltzmann learning of the neural network and the weights were adjusted according to the area of networks, number of nodes and rounds, the initial energy of nodes (E0), transmission energy of nodes (d < d0), data reviving energy (ERX), data aggregation energy (EDA), energy dissipation on free space (εfs), energy dissipation of multi-path delay (ε mp) and the packet size. The results of the present study revealed that the packet heads remains constant during the initial time period (up to 2500 seconds), and exhibited a sharp increase thereafter. The network energy consumption remains constant up to 2300 s and exhibited a sharp increase thereafter. High energy use after 2300 seconds describes the faulty occurrence in the network and leads to decreased reliability (%) of the existing protocol. The energy consumption was substantially reduced by 15 J (38.5%) due to the implementation of the newly proposed MRP-FT, compared with the existing PSO-FT protocol. The reduced delay of 22 packets was achieved with MRP-FT protocol, compared with the existing PSO-FT technique-based LEACH protocol. Nonetheless, the MRP-FT enhanced the packet overhead of 10.8% over the current protocol due to deploying more uniform clustering. Additionally, a 12% increase in reliability was achieved with the implementation of MRP-FT protocol emphasizing that network lifespan was prolonged efficiently with the proposed algorithm.
{"title":"Performance analysis of multi-layered clustering network using fault tolerance multipath routing protocol (MRP-FT) in a wireless sensor network (WSN)","authors":"Gagandeep Kaur","doi":"10.37190/ord230106","DOIUrl":"https://doi.org/10.37190/ord230106","url":null,"abstract":"Wireless sensor networks (WSNs) are ad hoc and self-configuring networks having the possibility that any sensor node can connect or leave the network. With no central controller in WSN, wireless sensor nodes are considered responsible for data routing in the networks. The wireless sensor nodes are very small in size and have limited resources, therefore, it becomes difficult to recharge or replace the battery of the sensor nodes at far places. The present study focused on reducing the battery consumption of the sensor nodes by the deployment of the newly proposed Fault Tolerance Multipath Routing Protocol (MRP-FT) as compared with the existing Low Energy Adaptive Clustering Hierarchy (LEACH) protocol under particle swarm optimisation based fault tolerant routing (PSO-FT) technique. The proposed algorithm of MRP-FT-based on the dynamic clustering technique using Boltzmann learning of the neural network and the weights were adjusted according to the area of networks, number of nodes and rounds, the initial energy of nodes (E0), transmission energy of nodes (d < d0), data reviving energy (ERX), data aggregation energy (EDA), energy dissipation on free space (εfs), energy dissipation of multi-path delay (ε mp) and the packet size. The results of the present study revealed that the packet heads remains constant during the initial time period (up to 2500 seconds), and exhibited a sharp increase thereafter. The network energy consumption remains constant up to 2300 s and exhibited a sharp increase thereafter. High energy use after 2300 seconds describes the faulty occurrence in the network and leads to decreased reliability (%) of the existing protocol. The energy consumption was substantially reduced by 15 J (38.5%) due to the implementation of the newly proposed MRP-FT, compared with the existing PSO-FT protocol. The reduced delay of 22 packets was achieved with MRP-FT protocol, compared with the existing PSO-FT technique-based LEACH protocol. Nonetheless, the MRP-FT enhanced the packet overhead of 10.8% over the current protocol due to deploying more uniform clustering. Additionally, a 12% increase in reliability was achieved with the implementation of MRP-FT protocol emphasizing that network lifespan was prolonged efficiently with the proposed algorithm.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82115923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The article presents proposals for a university management model supporting the process of strategic management at a university. The proposed model is based on the use of multi-criteria methods such as the 0–10 technique, object ranking, and optimisation methods – linear programming. The proposed solution integrates ranking and optimisation methods, the use of which may be helpful in the hands of managers in making management decisions. The proposed approach may also be helpful in developing a strategic scorecard, especially in the stage of formulating goals. It also enables the optimal selection of goals with the existing time constraints for the implementation of the strategy. The article presents a proposal for the use of the strategy implementation model and an example of its use. The strengths and weaknesses of the model were also indicated.
{"title":"The use of rank and optimisation methods in strategic management in higher education","authors":"R. Ryńca, Natalia Piórkowska","doi":"10.37190/ord230107","DOIUrl":"https://doi.org/10.37190/ord230107","url":null,"abstract":"The article presents proposals for a university management model supporting the process of strategic management at a university. The proposed model is based on the use of multi-criteria methods such as the 0–10 technique, object ranking, and optimisation methods – linear programming. The proposed solution integrates ranking and optimisation methods, the use of which may be helpful in the hands of managers in making management decisions. The proposed approach may also be helpful in developing a strategic scorecard, especially in the stage of formulating goals. It also enables the optimal selection of goals with the existing time constraints for the implementation of the strategy. The article presents a proposal for the use of the strategy implementation model and an example of its use. The strengths and weaknesses of the model were also indicated.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72900463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The occurrence of a disaster and the appearance of a new product are items of news that can reach many people rapidly. Decision-makers would like to know how many individuals will obtain such information. In this paper, we study the case in which there are spreaders who think that the news is true and others that claim it is false. We simulate the propagation of a rumour and propose an algorithm for estimating the parameters of the resulting dynamical system. The relation between the parameters defining the simulation and the dynamical system is also studied. We conclude that the simulation describes the phenomenon well, in particular when the method proposed in this paper is used to estimate the parameters.
{"title":"Simulating the propagation of rumours with spreaders of distinct characters","authors":"Daniel Menció-Padrón, Gemayqzel Bouza-Allende","doi":"10.37190/ord230305","DOIUrl":"https://doi.org/10.37190/ord230305","url":null,"abstract":"The occurrence of a disaster and the appearance of a new product are items of news that can reach many people rapidly. Decision-makers would like to know how many individuals will obtain such information. In this paper, we study the case in which there are spreaders who think that the news is true and others that claim it is false. We simulate the propagation of a rumour and propose an algorithm for estimating the parameters of the resulting dynamical system. The relation between the parameters defining the simulation and the dynamical system is also studied. We conclude that the simulation describes the phenomenon well, in particular when the method proposed in this paper is used to estimate the parameters.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135599675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The authors develop an agent-based model of the market where firms and consumers exchange products. Consumers in the model are heterogeneous in terms of features, such as risk-aversion or owned assets, which impact their individual decisions. Consumers constantly learn about products’ features through personal experience, word-of-mouth, or advertising, update their expectations and share their opinions with others. From the supply-side of the model, firms can influence consumers with two marketing tools: advertising and pricing policy. Series of experiments have been conducted with the model to investigate the relationship between advertising and pricing and to understand the underlying mechanism. Marketing strategies have been evaluated in terms of generated profit and recommendations have been formulated.
{"title":"An agent-based model of consumer choice. An evaluation of the strategy of pricing and advertising","authors":"M. Kot","doi":"10.37190/ord220104","DOIUrl":"https://doi.org/10.37190/ord220104","url":null,"abstract":"The authors develop an agent-based model of the market where firms and consumers exchange products. Consumers in the model are heterogeneous in terms of features, such as risk-aversion or owned assets, which impact their individual decisions. Consumers constantly learn about products’ features through personal experience, word-of-mouth, or advertising, update their expectations and share their opinions with others. From the supply-side of the model, firms can influence consumers with two marketing tools: advertising and pricing policy. Series of experiments have been conducted with the model to investigate the relationship between advertising and pricing and to understand the underlying mechanism. Marketing strategies have been evaluated in terms of generated profit and recommendations have been formulated.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77523898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In a complex supply chain network, the production nodes, seller nodes, and buyers are connected randomly. We assume a process of joining two random nodes leading to the bivariate Poisson probability mass function. There exist two types of links- one is horizontal (H) and the other is vertical (V), which support the continuous flow of commodities through the supply chain. This induces competition among workers at a node to manage these two types of links within fixed constraints and creates bargaining to decide the optimal degree of both types of links at a node. We use the Nash security point to obtain the bargaining solution describing the optimal links. We reduce the carrying cost and ordering cost of inventory, which are contrary in their nature by introducing horizontal and vertical links, respectively. We modify the total cost function and establish a new economic order quantity (EOQ), optimal shortage quantity, and total optimal cost in terms of the optimal degree of H and V cooperation.
{"title":"Determination of EOQ in terms of optimum degrees of horizontal and vertical cooperation at a node of supply chain","authors":"P. P. Mishra, Chipem Zimik, S. Borkotokey","doi":"10.37190/ord220206","DOIUrl":"https://doi.org/10.37190/ord220206","url":null,"abstract":"In a complex supply chain network, the production nodes, seller nodes, and buyers are connected randomly. We assume a process of joining two random nodes leading to the bivariate Poisson probability mass function. There exist two types of links- one is horizontal (H) and the other is vertical (V), which support the continuous flow of commodities through the supply chain. This induces competition among workers at a node to manage these two types of links within fixed constraints and creates bargaining to decide the optimal degree of both types of links at a node. We use the Nash security point to obtain the bargaining solution describing the optimal links. We reduce the carrying cost and ordering cost of inventory, which are contrary in their nature by introducing horizontal and vertical links, respectively. We modify the total cost function and establish a new economic order quantity (EOQ), optimal shortage quantity, and total optimal cost in terms of the optimal degree of H and V cooperation.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84025194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Credit scores are critical for financial sector investors and government officials, so it is important to develop reliable, transparent and appropriate tools for obtaining ratings. This study aims to predict company credit scores with machine learning and modern statistical methods, both in sectoral and aggregated data. Analyses are made on 1881 companies operating in three different sectors that applied for loans from Turkey’s largest public bank. The results of the experiment are compared in terms of classification accuracy, sensitivity, specificity, precision and Mathews correlation coefficient. When the credit ratings are estimated on a sectoral basis, it is observed that the classification rate considerably changes. Considering the analysis results, it is seen that logistic regression analysis, support vector machines, random forest and XGBoost have better performance than decision tree and k-nearest neighbour for all data sets.
{"title":"A comparative study of corporate credit ratings prediction with machine learning","authors":"Seyyide Doğan, Yasin Büyükkör, Murat Atan","doi":"10.37190/ord220102","DOIUrl":"https://doi.org/10.37190/ord220102","url":null,"abstract":"Credit scores are critical for financial sector investors and government officials, so it is important to develop reliable, transparent and appropriate tools for obtaining ratings. This study aims to predict company credit scores with machine learning and modern statistical methods, both in sectoral and aggregated data. Analyses are made on 1881 companies operating in three different sectors that applied for loans from Turkey’s largest public bank. The results of the experiment are compared in terms of classification accuracy, sensitivity, specificity, precision and Mathews correlation coefficient. When the credit ratings are estimated on a sectoral basis, it is observed that the classification rate considerably changes. Considering the analysis results, it is seen that logistic regression analysis, support vector machines, random forest and XGBoost have better performance than decision tree and k-nearest neighbour for all data sets.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78067152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The main objective of this paper is to present an example of the IT system implementation with advanced mathematical optimisation for job scheduling. The proposed genetic procedure leads to the Pareto front, and the application of the multiple criteria decision aiding (MCDA) approach allows extraction of the final solution. Definition of the key performance indicator (KPI) reflecting relevant features of the solutions, and the efficiency of the genetic procedure provide the Pareto front comprising the representative set of feasible solutions. The application of chosen MCDA, namely elimination et choix traduisant la réalité (ELECTRE) method, allows for the elicitation of the decision maker (DM) preferences and subsequently leads to the final solution. This solution fulfils all of the DM expectations and constitutes the best trade-off between considered KPIs. The proposed method is an efficient combination of genetic optimisation and the MCDA method.
{"title":"Multi-criteria human resources planning optimisation using genetic algorithms enhanced with MCDA","authors":"M. Jurczak, Grzegorz Miebs, R. Bachorz","doi":"10.37190/ord220404","DOIUrl":"https://doi.org/10.37190/ord220404","url":null,"abstract":"The main objective of this paper is to present an example of the IT system implementation with advanced mathematical optimisation for job scheduling. The proposed genetic procedure leads to the Pareto front, and the application of the multiple criteria decision aiding (MCDA) approach allows extraction of the final solution. Definition of the key performance indicator (KPI) reflecting relevant features of the solutions, and the efficiency of the genetic procedure provide the Pareto front comprising the representative set of feasible solutions. The application of chosen MCDA, namely elimination et choix traduisant la réalité (ELECTRE) method, allows for the elicitation of the decision maker (DM) preferences and subsequently leads to the final solution. This solution fulfils all of the DM expectations and constitutes the best trade-off between considered KPIs. The proposed method is an efficient combination of genetic optimisation and the MCDA method.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83566503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Bouchentouf, Abdelhak Guendouzi, Meriem Houalef, Shakir Majid
In this paper, we analyze an M/M/1 queueing system under both single and multiple working vacation policies, multiphase random environment, waiting server, balking and reneging. When the system is in operative phase j = 1,2,...,K, customers are served one by one. Whenever the system becomes empty, the server waits a random amount of time before taking a vacation, causing the system to move to working vacation phase 0 at which new arrivals are served at a lower rate. Using the probability generating function method, we obtain the distribution for the steady-state probabilities of the system. Then, we derive important performance measures of the queueing system. Finally, some numerical examples are illustrated to show the impact of system parameters on performance measures of the queueing system.
{"title":"Analysis of a single server queue in a multi-phase random environment with working vacations and customers’ impatience","authors":"A. Bouchentouf, Abdelhak Guendouzi, Meriem Houalef, Shakir Majid","doi":"10.37190/ord220202","DOIUrl":"https://doi.org/10.37190/ord220202","url":null,"abstract":"In this paper, we analyze an M/M/1 queueing system under both single and multiple working vacation policies, multiphase random environment, waiting server, balking and reneging. When the system is in operative phase j = 1,2,...,K, customers are served one by one. Whenever the system becomes empty, the server waits a random amount of time before taking a vacation, causing the system to move to working vacation phase 0 at which new arrivals are served at a lower rate. Using the probability generating function method, we obtain the distribution for the steady-state probabilities of the system. Then, we derive important performance measures of the queueing system. Finally, some numerical examples are illustrated to show the impact of system parameters on performance measures of the queueing system.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78427822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, panel regression models for 21 European countries and data covering the period between 2008 and 2014 were used to demonstrate that the distribution of working population across different occupational groups explains cross-country differences in terms of the average effective retirement age. Thus, while the great majority of previous studies verified the causal trade-off investigated on the basis of single-country micro data with reference to one economy, this study takes perspective of cross-country diversity in terms of the investigated relationship. The confirmed link holds even when controlling inter alia for health status, education, unemployment, old-dependency ratio, interest rate, GDP per capita, or the share of salaries and wages in GDP. An important practical implication for the policy-makers is that decisions limited only to the increase in the universal pensionable age cannot be effective, since the occupational composition of an economy is very relevant.
{"title":"Occupational composition of an economy and effective retirement age across European countries: an econometric analysis","authors":"F. Chybalski","doi":"10.37190/ord220305","DOIUrl":"https://doi.org/10.37190/ord220305","url":null,"abstract":"In this study, panel regression models for 21 European countries and data covering the period between 2008 and 2014 were used to demonstrate that the distribution of working population across different occupational groups explains cross-country differences in terms of the average effective retirement age. Thus, while the great majority of previous studies verified the causal trade-off investigated on the basis of single-country micro data with reference to one economy, this study takes perspective of cross-country diversity in terms of the investigated relationship. The confirmed link holds even when controlling inter alia for health status, education, unemployment, old-dependency ratio, interest rate, GDP per capita, or the share of salaries and wages in GDP. An important practical implication for the policy-makers is that decisions limited only to the increase in the universal pensionable age cannot be effective, since the occupational composition of an economy is very relevant.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74894163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In previous research, the Extended Order Scale (EOS) dedicated to risk assessment was analysed. It was characterised by a Numerical Order Scale (NOS) evaluated by trapezoidal oriented fuzzy numbers (TrOFNs). However, the research showed that EOS with two-stage orientation phases, was too complicated. Therefore, the main aim of our paper is to simplify a Complete Order Scale (COS) to a zero- or one-stage order scale and a hybrid approach. For this purpose, a way to calculate the scoring function is presented. The results show that changes in the COS structure influence the values of a scoring function. Replacing just one linguistic indicator gives different results. Another finding of the research is the method’s flexibility that allows an expert to individually choose the most suitable COS. The research proves that the boundary between various linguistic labels cannot be precisely defined. However, knowledge of a formal COS structure allows it to be transformed into a less complex one.
{"title":"Modifications of order scales for assessing debtors","authors":"Aleksandra Wójcicka-Wójtowicz, Krzysztof Piasecki","doi":"10.37190/ord220309","DOIUrl":"https://doi.org/10.37190/ord220309","url":null,"abstract":"In previous research, the Extended Order Scale (EOS) dedicated to risk assessment was analysed. It was characterised by a Numerical Order Scale (NOS) evaluated by trapezoidal oriented fuzzy numbers (TrOFNs). However, the research showed that EOS with two-stage orientation phases, was too complicated. Therefore, the main aim of our paper is to simplify a Complete Order Scale (COS) to a zero- or one-stage order scale and a hybrid approach. For this purpose, a way to calculate the scoring function is presented. The results show that changes in the COS structure influence the values of a scoring function. Replacing just one linguistic indicator gives different results. Another finding of the research is the method’s flexibility that allows an expert to individually choose the most suitable COS. The research proves that the boundary between various linguistic labels cannot be precisely defined. However, knowledge of a formal COS structure allows it to be transformed into a less complex one.","PeriodicalId":43244,"journal":{"name":"Operations Research and Decisions","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81357945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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