Pub Date : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751269
C. Soumali, M. Belattar
In this paper, we propose a novel wireless-powered hybrid (downlink and uplink) NOMA system to enable uplink NOMA transmission. By means of harvested energy from radio frequencies, two scenarios are proposed to feed energy to NOMA users. In the first scenario a power beacon transmit energy signal to different NOMA users, such users deploy harvested energy to transmit their own information signals in uplink to the base station. However in the second scenario, the base station transmit information signal in downlink to the users in the first time, then the base station feeds the users in the second time, in the third time users transmit their own information signals in uplink to the base station.
{"title":"Analysis of the Cooperative NOMA performance systems with Energy Harvesting strategies","authors":"C. Soumali, M. Belattar","doi":"10.1109/INFOTEH53737.2022.9751269","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751269","url":null,"abstract":"In this paper, we propose a novel wireless-powered hybrid (downlink and uplink) NOMA system to enable uplink NOMA transmission. By means of harvested energy from radio frequencies, two scenarios are proposed to feed energy to NOMA users. In the first scenario a power beacon transmit energy signal to different NOMA users, such users deploy harvested energy to transmit their own information signals in uplink to the base station. However in the second scenario, the base station transmit information signal in downlink to the users in the first time, then the base station feeds the users in the second time, in the third time users transmit their own information signals in uplink to the base station.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"160 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91385018","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751288
Borislav Đorđević, V. Timčenko, Dušan Sakić, Nikola Davidovic
This paper presents results obtained for the performance comparison of two type 1 hypervisors, ESXi 6.5 and Xen 8.0. We tested their performance through file system testing procedures using software Filebench, which is a benchmark for file and storage systems evaluation. Both analyzed hypervisors were tested while keeping equal software and hardware conditions. Centos 8.5 is chosen as the guest operating system, and it was installed on the generated virtual machines. To obtain valid results, the hypervisor performances are compared for systems with one, two, and three virtual machines. Initially, we defined the mathematical modeling of the workloads, set up hypervisor environment and hypotheses related to expected behavior, and later confirmed with the obtained results.
{"title":"File system performance for type-1 hypervisors on the Xen and VMware ESXi","authors":"Borislav Đorđević, V. Timčenko, Dušan Sakić, Nikola Davidovic","doi":"10.1109/INFOTEH53737.2022.9751288","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751288","url":null,"abstract":"This paper presents results obtained for the performance comparison of two type 1 hypervisors, ESXi 6.5 and Xen 8.0. We tested their performance through file system testing procedures using software Filebench, which is a benchmark for file and storage systems evaluation. Both analyzed hypervisors were tested while keeping equal software and hardware conditions. Centos 8.5 is chosen as the guest operating system, and it was installed on the generated virtual machines. To obtain valid results, the hypervisor performances are compared for systems with one, two, and three virtual machines. Initially, we defined the mathematical modeling of the workloads, set up hypervisor environment and hypotheses related to expected behavior, and later confirmed with the obtained results.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"8 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84242087","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751255
F. Dengiz
This work is completed as a part of an exoskeleton project that was started to solve a specific problem. The scope covers the research and development of a lightweight mobile active upper-body exoskeleton for industrial workers who are lifting heavy loads on daily basis. It shall be a powered electromechanical device to decrease the musculoskeletal fatigue on the user with human augmentation properties. There will be certain constraints such as body part, mobility, and activity. The proposed design is the most optimized version that can be produced with the current state of the related studies.
{"title":"Research and Development on Mobile Powered Upper-Body Exoskeletons for Industrial Usage","authors":"F. Dengiz","doi":"10.1109/INFOTEH53737.2022.9751255","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751255","url":null,"abstract":"This work is completed as a part of an exoskeleton project that was started to solve a specific problem. The scope covers the research and development of a lightweight mobile active upper-body exoskeleton for industrial workers who are lifting heavy loads on daily basis. It shall be a powered electromechanical device to decrease the musculoskeletal fatigue on the user with human augmentation properties. There will be certain constraints such as body part, mobility, and activity. The proposed design is the most optimized version that can be produced with the current state of the related studies.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"17 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89232112","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751252
Amer Ratković, Šeila Bećirović, Irfan Prazina, V. Okanović
In this paper, the design and implementation of parallel instrumented tests of Android applications are presented. Instrumented unit tests are tests that run on physical devices and emulators, and they can take advantage of the Android framework APIs. Android is the leading mobile operating system worldwide and the quality of mobile applications is as important as in any other desktop or web application. Evaluation and quality of those applications are accomplished by using automated testing tools. Parallel testing radically reduces the cost and time with regard to traditional testing methodologies. The paper uses a method and tools developed by Roman Kushnarenko from Medisafe. All the tools are available on the author's GitHub repository under the MIT license. The method is benchmarked on a simple application with different devices and emulators. Experiments show how tests parallelization scales with a different number of tests and devices.
{"title":"Benchmark of a Method for Instrumented Tests Parallelization in Android Applications","authors":"Amer Ratković, Šeila Bećirović, Irfan Prazina, V. Okanović","doi":"10.1109/INFOTEH53737.2022.9751252","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751252","url":null,"abstract":"In this paper, the design and implementation of parallel instrumented tests of Android applications are presented. Instrumented unit tests are tests that run on physical devices and emulators, and they can take advantage of the Android framework APIs. Android is the leading mobile operating system worldwide and the quality of mobile applications is as important as in any other desktop or web application. Evaluation and quality of those applications are accomplished by using automated testing tools. Parallel testing radically reduces the cost and time with regard to traditional testing methodologies. The paper uses a method and tools developed by Roman Kushnarenko from Medisafe. All the tools are available on the author's GitHub repository under the MIT license. The method is benchmarked on a simple application with different devices and emulators. Experiments show how tests parallelization scales with a different number of tests and devices.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"46 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76544229","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751285
Zorana Štaka, M. Vuković, V. Vujovic
Digital transformation represents a connective tissue of the global economic system and therefore is an unavoidable element in the process of improvement, both developed and underdeveloped countries. In contrast to digitalization, which was the initiator of digital transformation and relied exclusively on the introduction of digital technologies, digital transformation is interpreted as much wider and requires a special set of skills and competencies. From the perspective of technological innovations, which is the key segment of this process, it is necessary to recognize relevant elements that ensure that the process of digital transformation runs smoothly. Initially, in order to identify the digital competencies of which the process consists, it is necessary to analyze the process of digital transformation itself. After the analysis, the focus shifts to the digital competencies needed to fulfill the identified skills. In this paper, an analysis of digital transformation is performed and the necessary competencies that employees need to have for this process to be successful within the business ecosystem are identified. Relying on DIGCOMP as guidance for digital competencies, recommendations and suggestions were formed in order to connect these two areas.
{"title":"The Role of Digital Competencies in the Process of Digital Transformation","authors":"Zorana Štaka, M. Vuković, V. Vujovic","doi":"10.1109/INFOTEH53737.2022.9751285","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751285","url":null,"abstract":"Digital transformation represents a connective tissue of the global economic system and therefore is an unavoidable element in the process of improvement, both developed and underdeveloped countries. In contrast to digitalization, which was the initiator of digital transformation and relied exclusively on the introduction of digital technologies, digital transformation is interpreted as much wider and requires a special set of skills and competencies. From the perspective of technological innovations, which is the key segment of this process, it is necessary to recognize relevant elements that ensure that the process of digital transformation runs smoothly. Initially, in order to identify the digital competencies of which the process consists, it is necessary to analyze the process of digital transformation itself. After the analysis, the focus shifts to the digital competencies needed to fulfill the identified skills. In this paper, an analysis of digital transformation is performed and the necessary competencies that employees need to have for this process to be successful within the business ecosystem are identified. Relying on DIGCOMP as guidance for digital competencies, recommendations and suggestions were formed in order to connect these two areas.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"5 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90010341","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751293
Bożena-Szczucka Lasota, T. Wȩgrzyn, J. Piwnik, W. Tarasiuk, K. I. Wilczyński
The article analyzes the possibility of making a proper joint of high yield structural on the example of steel S690QL (1.8928). Various grades of steel are used more and more frequently for the construction of means of transport and they are used to make homogeneous and mixed joints. The aim of the article is the correct selection of parameters for welding the joint of the mobile landing elements made of S690QL steel with a thickness of 6 mm. It was decided to check the influence of welding parameters on the correctness of the joint made. Various additive materials were used, notably the electrode wires and various shielding gases. Non-destructive and destructive tests were performed to check the quality of the mixed joint.
{"title":"Welding of S690QL steel in the automotive industry","authors":"Bożena-Szczucka Lasota, T. Wȩgrzyn, J. Piwnik, W. Tarasiuk, K. I. Wilczyński","doi":"10.1109/INFOTEH53737.2022.9751293","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751293","url":null,"abstract":"The article analyzes the possibility of making a proper joint of high yield structural on the example of steel S690QL (1.8928). Various grades of steel are used more and more frequently for the construction of means of transport and they are used to make homogeneous and mixed joints. The aim of the article is the correct selection of parameters for welding the joint of the mobile landing elements made of S690QL steel with a thickness of 6 mm. It was decided to check the influence of welding parameters on the correctness of the joint made. Various additive materials were used, notably the electrode wires and various shielding gases. Non-destructive and destructive tests were performed to check the quality of the mixed joint.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"19 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75048117","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751323
Aleksandar Gavrić, Dušan Vujošcvić, Nemanja Radosavljević, Petar Prvulović
Wireless sensor networks (WSN) often generate data with high frequency per unit time. Values from sensor measurements are often redundant and provide little or no information. Methods of dimension reduction can be applied and thus only data of interest can be preserved for the purpose of effective analysis of wireless sensor networks' data. The authors show experimentally that it is possible to build more successful predictive models by reducing dimensions and discuss the potential advantages of reducing the spatial and temporal dimensions of sensor measurements in different applications. Authors present the implementation and analysis of an efficient distributed system that enables search, ranking, indexing, machine learning analysis and visualization of data from WSNs, processed in real-time.
{"title":"Real-Time Data Processing Techniques for a Scalable Spatial and Temporal Dimension Reduction","authors":"Aleksandar Gavrić, Dušan Vujošcvić, Nemanja Radosavljević, Petar Prvulović","doi":"10.1109/INFOTEH53737.2022.9751323","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751323","url":null,"abstract":"Wireless sensor networks (WSN) often generate data with high frequency per unit time. Values from sensor measurements are often redundant and provide little or no information. Methods of dimension reduction can be applied and thus only data of interest can be preserved for the purpose of effective analysis of wireless sensor networks' data. The authors show experimentally that it is possible to build more successful predictive models by reducing dimensions and discuss the potential advantages of reducing the spatial and temporal dimensions of sensor measurements in different applications. Authors present the implementation and analysis of an efficient distributed system that enables search, ranking, indexing, machine learning analysis and visualization of data from WSNs, processed in real-time.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"54 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73890026","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751272
Nemanja Radosavljević, Petar Prvulović, Dušan Vujošević, Aleksandar Gavrić
In this paper, the authors describe typical topologies used in wireless sensor networks (WSN) and A3 protocol, one of the most used topology construction protocols. The authors create a simulated environment using an Atarraya simulator. Simulation parameters depict a typical case of WSN application for monitoring a rectangular open field of 16 hectares. Simulation results show traffic load measured in number of messages per each node exchanged during simulated network lifetime. Messages are split into sent and received, and sub split into small and large messages. Results are presented in both tabular and graphical form, which provides an easy to comprehend method to check if the network satisfies given constraints. The use of a simulation environment and the obtained results are of great importance in early stages of WSN implementation in a natural environment. They enable simulation of expected traffic flow, estimate a battery powered network lifetime or validate an estimated amount of traffic which sensor nodes need to pass through, especially in cases where WSN deployment is irreversible due to sensor nodes inaccessibility after placement.
{"title":"Traffic Analysis of A3 Topology Construction Protocol in Wireless Sensor Networks","authors":"Nemanja Radosavljević, Petar Prvulović, Dušan Vujošević, Aleksandar Gavrić","doi":"10.1109/INFOTEH53737.2022.9751272","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751272","url":null,"abstract":"In this paper, the authors describe typical topologies used in wireless sensor networks (WSN) and A3 protocol, one of the most used topology construction protocols. The authors create a simulated environment using an Atarraya simulator. Simulation parameters depict a typical case of WSN application for monitoring a rectangular open field of 16 hectares. Simulation results show traffic load measured in number of messages per each node exchanged during simulated network lifetime. Messages are split into sent and received, and sub split into small and large messages. Results are presented in both tabular and graphical form, which provides an easy to comprehend method to check if the network satisfies given constraints. The use of a simulation environment and the obtained results are of great importance in early stages of WSN implementation in a natural environment. They enable simulation of expected traffic flow, estimate a battery powered network lifetime or validate an estimated amount of traffic which sensor nodes need to pass through, especially in cases where WSN deployment is irreversible due to sensor nodes inaccessibility after placement.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"12 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85359381","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751273
A. Borodzhieva
The paper presents the implementation of a project-based approach used in the course “Telecommunication Security” for the seventh-semester students-bachelors from the specialty “Internet and Mobile Communications” at the University of Ruse “Angel Kanchev” when teaching the knapsack problem. Working on projects, one of the trends of future education, Education 4.0, allows the development of basic 21st-century skills, such as literacy, numeracy, ICT literacy, creativity, initiative, critical thinking, problem-solving skills, etc.
{"title":"Project-Based Learning for Teaching the Knapsack Problem in the Course “Telecommunication Security”","authors":"A. Borodzhieva","doi":"10.1109/INFOTEH53737.2022.9751273","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751273","url":null,"abstract":"The paper presents the implementation of a project-based approach used in the course “Telecommunication Security” for the seventh-semester students-bachelors from the specialty “Internet and Mobile Communications” at the University of Ruse “Angel Kanchev” when teaching the knapsack problem. Working on projects, one of the trends of future education, Education 4.0, allows the development of basic 21st-century skills, such as literacy, numeracy, ICT literacy, creativity, initiative, critical thinking, problem-solving skills, etc.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"22 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85561182","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 : 2022-03-16DOI: 10.1109/INFOTEH53737.2022.9751329
Anđelko Aleksić, D. Rodić, M. Sekulić, Marin Gostimirović, B. Savković
The objective of this paper is to investigate the effect of cutting parameters on surface roughness during turning of CPM 10V steel with a coated cutting tool. Machining of CPM 10V steel and finding a suitable tool is very challenging due to its physical and mechanical properties, especially since the machining of this material has not been extensively researched. The experiments were carried out using an Index GU-600 CNC lathe and the surface roughness Ra was measured in process. A three-factorial three-level experimental design was used for the experiments. Statistical method analysis of variance (ANOVA) is applied to study the effects of cutting speed, feed rate, and depth of cut on surface roughness. The results of this study show that feed rate and the depth of cut have the most significant effect on surface roughness. The developed model can be used in the machining industry to predict and analyze cutting parameters for optimal surface roughness.
{"title":"Effect of cutting parameters on surface roughness in turning of CPM 10V steel","authors":"Anđelko Aleksić, D. Rodić, M. Sekulić, Marin Gostimirović, B. Savković","doi":"10.1109/INFOTEH53737.2022.9751329","DOIUrl":"https://doi.org/10.1109/INFOTEH53737.2022.9751329","url":null,"abstract":"The objective of this paper is to investigate the effect of cutting parameters on surface roughness during turning of CPM 10V steel with a coated cutting tool. Machining of CPM 10V steel and finding a suitable tool is very challenging due to its physical and mechanical properties, especially since the machining of this material has not been extensively researched. The experiments were carried out using an Index GU-600 CNC lathe and the surface roughness Ra was measured in process. A three-factorial three-level experimental design was used for the experiments. Statistical method analysis of variance (ANOVA) is applied to study the effects of cutting speed, feed rate, and depth of cut on surface roughness. The results of this study show that feed rate and the depth of cut have the most significant effect on surface roughness. The developed model can be used in the machining industry to predict and analyze cutting parameters for optimal surface roughness.","PeriodicalId":6839,"journal":{"name":"2022 21st International Symposium INFOTEH-JAHORINA (INFOTEH)","volume":"54 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90556407","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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