Tehnika最新文献 - Book学术

Hydrodynamic model recalibration: Case study of the Drmno open cast coal mine 水动力模型再标定:以Drmno露天煤矿为例

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2301031p

D. Polomcic, Dragoljub Bajić, T. Šubaranović

引用次数: 0

The impact of the COVID-19 pandemic on digital infrastructure and services COVID-19大流行对数字基础设施和服务的影响

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2301055b

Ana Bezarević, B. Mikavica, A. Kostić-Ljubisavljević

{"title":"The impact of the COVID-19 pandemic on digital infrastructure and services","authors":"Ana Bezarević, B. Mikavica, A. Kostić-Ljubisavljević","doi":"10.5937/tehnika2301055b","DOIUrl":"https://doi.org/10.5937/tehnika2301055b","url":null,"abstract":"The COVID-19 pandemic has caused drastic changes in the telecommunications and information and communication technologies market. The telecommunications sector is becoming one of the key ones in combating the consequences caused by the pandemic. It appears that digitalization, right behind health care, is crucial for successfully overcoming the new situations and that its role will be even more dominant in the future. Access to the Internet has provided an opportunity for everyday life to unfold. However, due to the growing need for network access, congestion occurs and the availability of consumable resources is reduced. It was necessary to efficiently solve the new problems on the network and overcome all the challenges to make the digital infrastructure more ready and reliable for future emergencies. In this paper, the importance of the digital infrastructure and the availability of telecommunication services during the COVID-19 pandemic are analyzed. The effects of the growing Internet traffic volume on the availability and network performances are presented. Potential critical segments and limitations of the existing digital infrastructure, as well as the future development goals for telecommunication networks, are identified. In addition, the effects of the COVID-19 pandemic on the digital divide and digital economies are observed.","PeriodicalId":22484,"journal":{"name":"Tehnika","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71133036","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}

引用次数: 0

Track geometry quality management 轨道几何质量管理

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2304403p

Z. Popović, L. Lazarević

引用次数: 0

"Improve" and "Control" tools in assembly of micro components: A case study “改进”和“控制”微型部件装配工具:一个案例研究

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2305607j

Nemanja Janev, Vesna Spasojević-Brkić, Mirjana Misita, Martina Perišić, Neda Papić

{"title":"\"Improve\" and \"Control\" tools in assembly of micro components: A case study","authors":"Nemanja Janev, Vesna Spasojević-Brkić, Mirjana Misita, Martina Perišić, Neda Papić","doi":"10.5937/tehnika2305607j","DOIUrl":"https://doi.org/10.5937/tehnika2305607j","url":null,"abstract":"The process of assembling micro components requires careful planning where precise and reliable data collecting is necessary due to a short production cycle time. After determining the shortages of the current data monitoring system, in this paper, by using the \"Improve\" and \"Control\" phases of DMAIC cycle, the development and later testing of a new tool for automatic capture and analysis of data obtained from the machine was done. SWOT analysis was used to establish the production site's and current manufacturing execution system strengths and weaknesses, opportunities and threats, which were then utilized to create the newly developed solution accurate and feasible. A tool calibration data was obtained on 9 machines in automotive company's micro component assembly unit. To confirm the accuracy of the data, a RunAtRate test was done on the machines, and by using hypothesis testing, the initial reliability of the new solution was determined. Further testing and comparison revealed that the newly proposed tool recorded 73-80% greater downtime and 40-50% more defective parts than the previously installed system. Accordingly, the usefulness of the proposed Lean Six SIGMA tool is confirmed, and for periodic accuracy checks and further improvement, it is necessary to apply the PDCA cycle.","PeriodicalId":22484,"journal":{"name":"Tehnika","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135611034","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}

引用次数: 0

Challenges of corporate restructuring of public companies in the Republic of Serbia 塞尔维亚共和国上市公司重组的挑战

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2305595m

Milutin Mojsilović, Ljubomir Obradović

{"title":"Challenges of corporate restructuring of public companies in the Republic of Serbia","authors":"Milutin Mojsilović, Ljubomir Obradović","doi":"10.5937/tehnika2305595m","DOIUrl":"https://doi.org/10.5937/tehnika2305595m","url":null,"abstract":"This paper deals with restructuring of public enterprises in Serbia, focusing on the identification of challenges, as well as the analysis of all the key aspects relevant to the process of the restructuring. It points out the importance of theoretical perspectives and the state with its institutional framework in providing support and restructuring guidelines. Financial challenges and social aspects are also highlighted, as well as employee protection measures. It also deals with the influence of politics, economy and human capital on the process itself. The purpose of this paper is to provide a comprehensive insight into the challenges, implications, and both theoretical and practical sides to restructuring of public enterprises. The goal is to understand the complexity and specific details of the restructuring, while identifying all the key factors of the process-success and obstacles. A detailed study of relevant literature, research papers, articles and regulations had been conducted prior to writing this paper. Applicable restructuring theoretical models and concepts were also examined. After analysis and research, it was noticed that the restructuring of public enterprises in Serbia faces different challenges, such as: political interference, lack of financial resources, structure inflexibility, and resistance to change. The state and institutions play an important role in the process of restructuring. We emphasized the importance of adequate employee protection during restructuring and provided guidelines for achieving social justice. The results provide a starting point for further research, including those regarding specific sectors, implementing new technologies and some innovative approaches to restructuring.","PeriodicalId":22484,"journal":{"name":"Tehnika","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135611255","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}

引用次数: 0

Recultivaction of opencast mine of clay "Garajevac Istok", near Novi Bečej 在Novi beej附近的“Garajevac Istok”粘土露天矿的复垦

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2305547j

Branka Jovanović, Svetlana Polavder, Željko Praštalo, Rade Šarac

{"title":"Recultivaction of opencast mine of clay \"Garajevac Istok\", near Novi Bečej","authors":"Branka Jovanović, Svetlana Polavder, Željko Praštalo, Rade Šarac","doi":"10.5937/tehnika2305547j","DOIUrl":"https://doi.org/10.5937/tehnika2305547j","url":null,"abstract":"The surface exploitation of mineral raw materials is realized in the natural environment, causing the degradation of the narrower and wider space: the change of the physical appearance of the terrain and the degradation of the soil and autochthonous vegetation cover. The recultivation of the surface mine area, after the exploitation of mineral raw materials, is an important and mandatory measure in the function of environmental protection. In a biologically empty space, with damaged or destroyed natural content, in parallel with the slow and long-lasting process of spontaneous self-revitalization, technical and biological reclamation measures and procedures are applied to control and accelerate the revitalization process.The subject of this work is the design of reclamation on the surfaces affected by the exploitation of clay, on the example of the Garajevac Istok surface mine near Novi Bečej, with the aim of creating habitats for plant and animal life. The planned goals of the reclamation of the post-exploitation area of the Garajevac Istok surface mine will be realized by applying a combination of afforestation measures and spontaneous self-reclamation.","PeriodicalId":22484,"journal":{"name":"Tehnika","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135612089","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}

引用次数: 0

Summary comparison of geothermal energy with solar energy and wind energy 地热能与太阳能和风能的概要比较

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2301037t

Rudolf Tot

引用次数: 0

Research methods in the function of measuring and improving quality 研究方法在测量和提高质量中的作用

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2303357d

Branko Đedović, R. Knežević, Marko Paić

引用次数: 0

Mineral raw materials of Serbia on the list of critical minerals of the European Commission (CRM EU-2020) during the Covid-19 pandemic and harmonized in the UNFC-2009 system and the PERC standard 在2019冠状病毒病大流行期间，塞尔维亚的矿物原材料被列入欧盟委员会(CRM EU-2020)的关键矿物清单，并在联合国气候变化框架公约-2009体系和PERC标准中进行了协调

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2303295v

R. Vukas

{"title":"Mineral raw materials of Serbia on the list of critical minerals of the European Commission (CRM EU-2020) during the Covid-19 pandemic and harmonized in the UNFC-2009 system and the PERC standard","authors":"R. Vukas","doi":"10.5937/tehnika2303295v","DOIUrl":"https://doi.org/10.5937/tehnika2303295v","url":null,"abstract":"The existence of mineralization, mining and deposits of non-ferrous and precious and other metals (Pb-Zn, Ag; Cu, Au, as well as B-Li, Mg, Sb, etc.) in the territory of Serbia is conditioned by the structural-geological-metallogenetic structure and processes formation of deposits of mineral raw materials in a certain period of geohistorical development. Mining activity in the territory of Serbia, i.e. extraction of non-ferrous and precious metal ores, goes back thousands of years, which resulted in the \"production\" of significant accumulations of mining and industrial waste. These facts indicate the existence of a significant mineral potential of Serbia, and the possibility of recovering metals through technological processes of waste material recycling. Mineral deposits are the primary sources, and accumulated mining and industrial waste are secondary sources of providing mineral resources such as Cu, Pb-Zn, Co, Ni, Al, Li, W, Bi, In, Te, Ga, Ge, REE and others, many of which are on the list of CRM EU-2020 or 2023. Critical minerals as a professional-formal term is not defined in Serbia, and in due to the specific way and extent of occurrence in nature, exhaustibility and non-renewable reserves, as well as the provision of certain countries or regions with solid mineral resources in certain socio-economic conditions (world crises, wars, embargoes, pandemics, etc.) become deficient, i.e. missing (on the market), i.e. in terms of supply chain. During the Covid 19 pandemic, publicly available data on critical raw materials in Serbia were analyzed, when it was assessed that e.g. for the supply chain of the health sector, only ten of them are available (Sb, Ba, B, Ge, In, Mg, F, ...). The solid mineral raw materials of Serbia classified into categories and classes of geological reserves (classes of mineral resources and reserves) can, for certain reporting purposes, be harmonized with the Mineral Resources/Reserves from international standards (PERC, JORC, Ni-43 101 and codes of UNFC).","PeriodicalId":22484,"journal":{"name":"Tehnika","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71133734","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}

引用次数: 0

The installation of fire detectors in special cases: The stairs case 特殊情况下火灾探测器的安装:楼梯情况

Tehnika Pub Date : 2023-01-01 DOI: 10.5937/tehnika2302245j

R. Jevtić, Ivana Janković

引用次数: 0