Pub Date : 2018-10-04DOI: 10.1504/IJMR.2018.10011162
Y. Rajpoot, R. G. Narayanan, Sumitesh Das
The present work aims at selecting the pin geometry for single-sided friction stir welding of steel, and modelling the double-sided FSW process, both through cellular automata finite element analyses. Cellular automata cells are used to hold initial grain size of the base sheets. The stirring action during the process is not modelled physically. Instead the heat flux and strain-rate attained are incorporated by models. In the first objective, by developing heat flux models, strain-rate and strain models for different pin profiles, and the final grain size distribution across the weld zone is predicted. The final pin profile predicted from the present work is not the same used by authors in the existing literature, as observed from grain size prediction. In the second objective, during double-sided friction stir welding, the grain size predictions are agreeing well with the existing data. The efficiency of the approach for tool selection has been demonstrated successfully. [Submitted 8 December 2016; Accepted 5 December 2017]
{"title":"Predicting the effect of tool configuration during friction stir welding by cellular automata finite element analyses","authors":"Y. Rajpoot, R. G. Narayanan, Sumitesh Das","doi":"10.1504/IJMR.2018.10011162","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10011162","url":null,"abstract":"The present work aims at selecting the pin geometry for single-sided friction stir welding of steel, and modelling the double-sided FSW process, both through cellular automata finite element analyses. Cellular automata cells are used to hold initial grain size of the base sheets. The stirring action during the process is not modelled physically. Instead the heat flux and strain-rate attained are incorporated by models. In the first objective, by developing heat flux models, strain-rate and strain models for different pin profiles, and the final grain size distribution across the weld zone is predicted. The final pin profile predicted from the present work is not the same used by authors in the existing literature, as observed from grain size prediction. In the second objective, during double-sided friction stir welding, the grain size predictions are agreeing well with the existing data. The efficiency of the approach for tool selection has been demonstrated successfully. [Submitted 8 December 2016; Accepted 5 December 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128213525","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}
Pub Date : 2018-10-04DOI: 10.1504/IJMR.2018.10011159
Mattias Svahn, Lars Vedmar, Carina Andersson
In this paper, a mathematical model is presented, by which the cutting forces in a gear hobbing process and the wear behaviour of the hob's all cutting teeth are predicted. The load on each individual hob cutting tooth varies heavily in the gear hobbing process. To predict the cutting force, and subsequently the tool wear, a detailed determination of the chip geometry is needed. The undeformed chip geometry is continuously determined by analytical differential description presented in previous research. In the model all cut chips are determined for the full production cycle of a gear blank, where the gear blank boundaries are considered. Considering the full production cycle is needed to get an understanding of the load the tool will experience and the wear behaviour of the hob teeth. [Submitted 17 January 2017; Accepted 24 November 2017]
{"title":"Prediction of the cutting forces in gear hobbing and the wear behaviour of the individual hob cutting teeth","authors":"Mattias Svahn, Lars Vedmar, Carina Andersson","doi":"10.1504/IJMR.2018.10011159","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10011159","url":null,"abstract":"In this paper, a mathematical model is presented, by which the cutting forces in a gear hobbing process and the wear behaviour of the hob's all cutting teeth are predicted. The load on each individual hob cutting tooth varies heavily in the gear hobbing process. To predict the cutting force, and subsequently the tool wear, a detailed determination of the chip geometry is needed. The undeformed chip geometry is continuously determined by analytical differential description presented in previous research. In the model all cut chips are determined for the full production cycle of a gear blank, where the gear blank boundaries are considered. Considering the full production cycle is needed to get an understanding of the load the tool will experience and the wear behaviour of the hob teeth. [Submitted 17 January 2017; Accepted 24 November 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"116 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121266412","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}
Pub Date : 2018-10-04DOI: 10.1504/IJMR.2018.10010721
Aydin Teymourifar, Gurkan Ozturk
In this paper, new due date assignment models and dispatching rules have been designed for the dynamic job shop scheduling problem. All of them have competitive results compared to the models from previous studies. The proposed dispatching rules have been evolved based on the modified and composite features of jobs. They have been compared with successful methods from the literature in a simulated environment. The simulation model has been validated by comparing the results with an analytical method. One of the rules has the best results in comparison with the other dispatching rules from the literature cited in this study. Another important matter which is considered in this paper is that the due date assignment model must be compatible with the used dispatching rule. Based on this approach, new due date assignment models are developed, which have the best results when combined with some dispatching rules. [Submitted 17 August 2016; Accepted 14 November 2017]
{"title":"New dispatching rules and due date assignment models for dynamic job shop scheduling problems","authors":"Aydin Teymourifar, Gurkan Ozturk","doi":"10.1504/IJMR.2018.10010721","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10010721","url":null,"abstract":"In this paper, new due date assignment models and dispatching rules have been designed for the dynamic job shop scheduling problem. All of them have competitive results compared to the models from previous studies. The proposed dispatching rules have been evolved based on the modified and composite features of jobs. They have been compared with successful methods from the literature in a simulated environment. The simulation model has been validated by comparing the results with an analytical method. One of the rules has the best results in comparison with the other dispatching rules from the literature cited in this study. Another important matter which is considered in this paper is that the due date assignment model must be compatible with the used dispatching rule. Based on this approach, new due date assignment models are developed, which have the best results when combined with some dispatching rules. [Submitted 17 August 2016; Accepted 14 November 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114578534","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}
Pub Date : 2018-08-02DOI: 10.1504/IJMR.2018.10010720
Zhehan Chen, Xiaohua Zhang, Ketai He
Selective laser melting (SLM) is one the most popular additive manufacturing technologies due to its ability to produce the complex parts. Online monitoring of the SLM process has been considered to be an effective approach to ensuring the safety of operations during the build and improve the part quality. Current researches largely focus on investigating the relationship between a single factor (such as temperature) and the process quality. In this paper, a systematic methodology for online monitoring the SLM process is a proposed, taking into consideration the relationships between multiple factors during melting, and their impact on the status of the devices and the parts being created. A framework of SLM process monitoring based on state space model is demonstrated, providing an integrated data structure for introducing data mining methods into SLM process online monitoring. The development of the state space model together with the parameters selection is described. [Submitted 12 February 2017; Accepted 21 November 2017]
{"title":"State space model for online monitoring selective laser melting process using data mining techniques","authors":"Zhehan Chen, Xiaohua Zhang, Ketai He","doi":"10.1504/IJMR.2018.10010720","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10010720","url":null,"abstract":"Selective laser melting (SLM) is one the most popular additive manufacturing technologies due to its ability to produce the complex parts. Online monitoring of the SLM process has been considered to be an effective approach to ensuring the safety of operations during the build and improve the part quality. Current researches largely focus on investigating the relationship between a single factor (such as temperature) and the process quality. In this paper, a systematic methodology for online monitoring the SLM process is a proposed, taking into consideration the relationships between multiple factors during melting, and their impact on the status of the devices and the parts being created. A framework of SLM process monitoring based on state space model is demonstrated, providing an integrated data structure for introducing data mining methods into SLM process online monitoring. The development of the state space model together with the parameters selection is described. [Submitted 12 February 2017; Accepted 21 November 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123710295","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}
Pub Date : 2018-08-02DOI: 10.1504/IJMR.2018.10010158
Yunxian Cui, Yi Liu, X. Wang, W. Ding, Qiuyu Liu
In this paper, the temperature measuring tool based on NiCr/NiSi thin film thermocouple is developed. 6,061 aluminium alloys is selected as the experiment object. Based on the cutting area temperat ...
{"title":"Research on measurement of cutting area temperature and its prediction model","authors":"Yunxian Cui, Yi Liu, X. Wang, W. Ding, Qiuyu Liu","doi":"10.1504/IJMR.2018.10010158","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10010158","url":null,"abstract":"In this paper, the temperature measuring tool based on NiCr/NiSi thin film thermocouple is developed. 6,061 aluminium alloys is selected as the experiment object. Based on the cutting area temperat ...","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128903580","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}
Pub Date : 2018-08-02DOI: 10.1504/IJMR.2018.10010159
E. Atzeni
Face grinding is a process that is capable of meeting both the productivity and flexibility demands of industry, with acceptable manufacturing costs. Efficient grinding is the result of an optimisation process that considers detailed knowledge of the interaction between a grinding wheel and the material of the workpiece, but which should also consider energy aspects. The face grinding process of flat surfaces has been analysed in this work through an experimental campaign, in an attempt to relate the grinding parameters to the forces and energy. Thus, a grinding apparatus was instrumented with a force measuring device in order to monitor the grinding forces applied during the removal of the material. The applied power and energy were also evaluated. The experimental results are discussed in this paper, and are related to the analytical relationships that were found to develop for the specific face grinding operation. [Submitted 12 March 2017; Accepted 7 October 2017]
{"title":"Force and energy considerations on the face grinding of flat surfaces","authors":"E. Atzeni","doi":"10.1504/IJMR.2018.10010159","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10010159","url":null,"abstract":"Face grinding is a process that is capable of meeting both the productivity and flexibility demands of industry, with acceptable manufacturing costs. Efficient grinding is the result of an optimisation process that considers detailed knowledge of the interaction between a grinding wheel and the material of the workpiece, but which should also consider energy aspects. The face grinding process of flat surfaces has been analysed in this work through an experimental campaign, in an attempt to relate the grinding parameters to the forces and energy. Thus, a grinding apparatus was instrumented with a force measuring device in order to monitor the grinding forces applied during the removal of the material. The applied power and energy were also evaluated. The experimental results are discussed in this paper, and are related to the analytical relationships that were found to develop for the specific face grinding operation. [Submitted 12 March 2017; Accepted 7 October 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"19 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113961995","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}
Pub Date : 2018-08-02DOI: 10.1504/IJMR.2018.10010157
Shahram Mirzaei Daryani, A. Amini
Knowing the mechanisms that allow organisations to detect environmental changes and being able to adapt and offer the proper response to them becomes especially relevant, because this knowledge might lead firms to attain a greater success by exploiting emerging opportunities and new sources of competitive advantages. Given the importance of organisational excellence and superior performance, this study aimed at the identification and prioritisation of managerial tools and techniques in impact on quality improvement. The statistical population consisted of management and industrial engineering professors of the Iranian universities and managers and experts of Urmia Tractor Manufacturing Company in the national context. First, by using the Delphi method and wrapping up experts' views 25 managerial tools and techniques were identified. Then by responding to the secondary questionnaire, experts prioritised the tools and techniques. Finally, to promote the quality of company's products and services, some strategies and guidelines are presented. [Submitted 25 April 2017; Accepted 7 October 2017]
{"title":"Identification and prioritisation of managerial tools and techniques in impact on quality improvement","authors":"Shahram Mirzaei Daryani, A. Amini","doi":"10.1504/IJMR.2018.10010157","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10010157","url":null,"abstract":"Knowing the mechanisms that allow organisations to detect environmental changes and being able to adapt and offer the proper response to them becomes especially relevant, because this knowledge might lead firms to attain a greater success by exploiting emerging opportunities and new sources of competitive advantages. Given the importance of organisational excellence and superior performance, this study aimed at the identification and prioritisation of managerial tools and techniques in impact on quality improvement. The statistical population consisted of management and industrial engineering professors of the Iranian universities and managers and experts of Urmia Tractor Manufacturing Company in the national context. First, by using the Delphi method and wrapping up experts' views 25 managerial tools and techniques were identified. Then by responding to the secondary questionnaire, experts prioritised the tools and techniques. Finally, to promote the quality of company's products and services, some strategies and guidelines are presented. [Submitted 25 April 2017; Accepted 7 October 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"2010 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125630643","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}
Pub Date : 2018-08-02DOI: 10.1504/IJMR.2018.10009143
Rezaeerad Mojtaba, M. Farahani, Omid Shapurgan
The widespread application of polymers has motivated researchers to improve their forming and joining processes. In this category, friction stir welding (FSW) proposed as an alternative for the traditional joining processes. In this paper, FSW with a threaded cylindrical tool was employed for dissimilar joining of sheets of polyethylene and polypropylene. In order to control the material flow, the used tool was equipped with a hot shoe. In the following, the influences of important process parameters such as tool rotation speed, tool traverse speed and tool tilt angle on the joint mechanical properties were investigated. In the optimum joining condition, composite welded joint with defect-free uniform microstructure, with strength equal to 99% of polyethylene and with higher elongation and hardness than the polyethylene was obtained. The optimum rotational speed equal to 1,860 rpm with the highest travel speed equal to 12.5 mm/min provide the welded joints with best mechanical properties. [Submitted 4 April 2017; Accepted 29 August 2017]
{"title":"Comprehensive investigation on the mechanical properties of friction stir composite joint from polyethylene-polypropylene","authors":"Rezaeerad Mojtaba, M. Farahani, Omid Shapurgan","doi":"10.1504/IJMR.2018.10009143","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10009143","url":null,"abstract":"The widespread application of polymers has motivated researchers to improve their forming and joining processes. In this category, friction stir welding (FSW) proposed as an alternative for the traditional joining processes. In this paper, FSW with a threaded cylindrical tool was employed for dissimilar joining of sheets of polyethylene and polypropylene. In order to control the material flow, the used tool was equipped with a hot shoe. In the following, the influences of important process parameters such as tool rotation speed, tool traverse speed and tool tilt angle on the joint mechanical properties were investigated. In the optimum joining condition, composite welded joint with defect-free uniform microstructure, with strength equal to 99% of polyethylene and with higher elongation and hardness than the polyethylene was obtained. The optimum rotational speed equal to 1,860 rpm with the highest travel speed equal to 12.5 mm/min provide the welded joints with best mechanical properties. [Submitted 4 April 2017; Accepted 29 August 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131251584","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}
Pub Date : 2018-07-25DOI: 10.1504/IJMR.2018.10010160
Q. Guo, MingYang Zhang, Yan Jiang, Bo Zhao
Ultrasonic milling is used more and more common in fields such as aerospace, mould and so on. Whereas, there are few literatures studying the ultrasonic milling. In consequence, focus on one of important skills for the ultrasonic milling process, instantaneous uncut chip thickness (IUCT) model for the cutter with non-uniform helix angle and complex toolpaths, is built and then a calculation theory is introduced to compute the IUCT using a numerical method. Subsequently, two examples of the toolpath are taken to show the validity of the presented method, the first one is the line toolpath and the second one is circle. The results is shown that the method in this paper can compute the IUCT values for the complex tool path, also, the method in this paper can be used by the cutter with non-uniform helix angles. [Submitted 19 December 2016; Accepted 24 October 2017]
{"title":"The determination of instantaneous uncut chip thickness for non-uniform helix angle tools with complex tool path in ultrasonic milling process","authors":"Q. Guo, MingYang Zhang, Yan Jiang, Bo Zhao","doi":"10.1504/IJMR.2018.10010160","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10010160","url":null,"abstract":"Ultrasonic milling is used more and more common in fields such as aerospace, mould and so on. Whereas, there are few literatures studying the ultrasonic milling. In consequence, focus on one of important skills for the ultrasonic milling process, instantaneous uncut chip thickness (IUCT) model for the cutter with non-uniform helix angle and complex toolpaths, is built and then a calculation theory is introduced to compute the IUCT using a numerical method. Subsequently, two examples of the toolpath are taken to show the validity of the presented method, the first one is the line toolpath and the second one is circle. The results is shown that the method in this paper can compute the IUCT values for the complex tool path, also, the method in this paper can be used by the cutter with non-uniform helix angles. [Submitted 19 December 2016; Accepted 24 October 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124226047","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}
Pub Date : 2018-07-25DOI: 10.1504/IJMR.2018.10010161
D. Du, Jianfei Sun, Sen Yang, Wuyi Chen
Tool wear and its service life have great influence on machining quality, production efficiency and cost. Tool wear is a three-dimensional phenomenon accompanied by physical and chemical factors. However, the tool wear model and evaluation standard characterised by two dimension are still widely used today. In order to explore the use of three-dimensional topography to track the tool wear trend and measure the tool wear condition, relatively high speed cutting experiments were done for cutting three kinds of materials. Laser scanning confocal microscope was used to measure the worn tool topography at different cutting times. After that, the deficiency of two-dimensional indicators and validity of three-dimensional topography in evaluating tool wear were analysed. Besides, some improved tool wear evaluation methods were proposed. [Submitted 19 December 2016; Accepted 24 October 2017]
{"title":"An investigation on measurement and evaluation of tool wear based on 3D topography","authors":"D. Du, Jianfei Sun, Sen Yang, Wuyi Chen","doi":"10.1504/IJMR.2018.10010161","DOIUrl":"https://doi.org/10.1504/IJMR.2018.10010161","url":null,"abstract":"Tool wear and its service life have great influence on machining quality, production efficiency and cost. Tool wear is a three-dimensional phenomenon accompanied by physical and chemical factors. However, the tool wear model and evaluation standard characterised by two dimension are still widely used today. In order to explore the use of three-dimensional topography to track the tool wear trend and measure the tool wear condition, relatively high speed cutting experiments were done for cutting three kinds of materials. Laser scanning confocal microscope was used to measure the worn tool topography at different cutting times. After that, the deficiency of two-dimensional indicators and validity of three-dimensional topography in evaluating tool wear were analysed. Besides, some improved tool wear evaluation methods were proposed. [Submitted 19 December 2016; Accepted 24 October 2017]","PeriodicalId":154059,"journal":{"name":"Int. J. Manuf. Res.","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134416019","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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