• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.426.2-426.2
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• 2016

Numerous of researches are being conducted to improve the efficiency of $Cu_2ZnSnSe_4$ (CZTSe)-based photovoltaic devices, which is one of the most promising candidates for low cost and environment-friendly solar cells. In this work, we concentrate on the back contact of the devices. A proper thickness of $MoSe_2$ in back contact structure is believed to enhance adhesion and ohmic contact between Mo back contact and absorber layer. Nevertheless, too thick $MoSe_2$ layers that are grown during high-temperature selenization process can impede the current collection, thus resulting in low cell performance. By applying molybdenum nitride as a barrier in back contact structure, we were able to control the thickness of $MoSe_2$ layer, which resulted in lower series resistance and higher fill factor of CZTSe devices. The phase transformation of Mo-N binary system was systematically studied by changing $N_2$ concentration during the sputtering process. With a proper phase of Mo-N fabricated by using an adequate partial pressure of $N_2$, the efficiency of CZTSe solar cells as high as 8.31% was achieved while the average efficiency was improved by about 2% with respect to that of the referent cells where no barrier layer was employed.

• Korean System Dynamics Review
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• v.9 no.2
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• pp.129-154
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• 2008

As a practical means to upgrade urban sustainability, this paper focuses on resource cyclical systems concerned with the waste of electric and electronic equipment (WEEE) in Korea. Borrowing System Dynamics concepts and approaches, it examines behavioral changes of WEEE dynamics to observe whether the existing management methods can be readjusted. The measurement is based upon both reuse and material and thermal recycle simulation works in the individual stage of WEEE discharge, collection, and treatment, going beyond the traditional recycle-only customs. This research estimates that the newly introduced Extended Producer Responsibility (EPR) system would definitely exert a significant impact on the final stage of WEEE treatment, decreasing the final treatment volume in the first half of the research period. The trend, nonetheless, would be reversed in the second half, mainly owing to the additional waste volume originated from the local government and recycling center. Sensitivity analysis poses, among others, that the local government-supported reuse center should take charge of a pivotal role in the long run. The research also shows that sufficientand necessary conditions for the WEEE management and treatment should be given to the combined efforts, both from the private sectors and the public domains. Based on these research findings, the paper recommends that key stakeholders including the producer and the public organizations should devise how to jointly carry out specific agenda centered around partnership or network buildings.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.2
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• pp.151-174
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• 2006

To improve the international competitiveness of research and academic libraries in Korea, it is essential to review the total amount of domestic information resources in comparison with those of other advanced countries, and then to make their best use. In this study, an attempt is made to estimate the annual budget for collecting foreign knowledge information resources spent by academic and research libraries in Korea. This budget estimate could be used for a basis for setting up the appropriate collection size and the efficient channel for distributing and sharing information resources among academic and research libraries on the governmental level. The total budget for collecting foreign knowledge information resources, including foreign monographs and scholarly journals in print, and the budget for foreign electronic journals, and web databases were estimated for academic libraries and research libraries, respectively, while the budget for international document delivery services was estimated without distinction between the types of libraries.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.3
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• pp.23-30
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• 2007

RFID it reads information which is it writes, the semiconductor chip for and the radio frequency system which uses the hazard antenna it has built-in transmission of information it talks. Formation which is transmitted like this collection and America which it filtrates wey the RFID search service back to inform the location of the server which has commodity information which relates with an object past record server. The hazard where measurement analysis result the leader for electronic interference does not occur consequently together from with verification test the power level which is received from the antenna grade where it stands must maintain minimum -55dBm and the electronic interference will not occur with the fact that, antenna and reel his recognition distance the maximum 7m until the recognition which is possible but smooth hazard it must stand and and with the fact that it will do from within and and and 3-4m it must be used Jig it is thought.

• Journal of the Korean Society for Library and Information Science
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• v.44 no.4
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• pp.413-433
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• 2010

The purpose of this study is to portray the current condition of digital reading rooms in public libraries in specific terms of information resource constituencies. With the growth in numbers of public libraries in Korea, emphasis was also put on digital information services using digital reading rooms in public libraries. However, it is also recognized that these digital reading rooms are merely traditional reading rooms with equipment. In this regard, the objective for the study was to identify and describe the types of electronic information resources in order to determine the rationale for the development of digital information resource management in public libraries. The focus was especially put on investigating the quality and the degree of perceived importance of electronic resources. Data for this case study was collected from four relatively big public libraries in three cities. The investigation was conducted by the document reviews and surveys and interviews with librarians and patrons. The study found that digital resource management should be put on a new stage, especially in terms of education and reliable information for the regional community. The study also added some suggestions for the future development and refinement of electronic resource management in public libraries.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.628-629
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• 2011

E-commerce is a kind of trade type between buyers and sellers rely on computer networks. Carried out according to certain standards of various business activities. e-commerce is based on modern information technology and network technology, financial electronic collection, management, information technology, business and trade information networks into one, aimed at logistics, capital flow and information flow of harmony and unity of the new trade, trade activities of the entire process, electronic, networking and digital. E-commerce has brought to the traditional ways of trading a huge impact, led to changes in economic structures, is a business revolution in the way and is recognized internationally as the 21st century is an important driver of economic development compared to current traditional companies. In this material, we first consider the current problem, analyze particular characteristics of clothing shopping mall to increase the purchasing power of customer. For these reasons, we describe the process for building the clothing site.

• Resources Recycling
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• v.26 no.4
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• pp.9-18
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• 2017

Recently, the amount of electronic scrap is rapidly increasing due to the rapid growth of the electronics industry. Among the components of electronic scrap, the printed circuit board(PCB) is an important recycling target which includes common metals, precious metals, and rare metals such as gold, silver, copper, tin, nickel and so on. In Korea, however, PCB recycling technologies are mainly commercialized by some major companies, and other process quantities are not accurately counted. According to present situation, several urban mining companies, research institutes, and universities are conducting research on recovery of valuable metals from PCBs and/or reusing them as raw materials that is different from existing commercialization process developed by major companies. In this study, we analyzed not only current status of collection/disposal process and recycling of waste PCBs in Korea but also the trend of recycling technologies in order to help resource circulation from waste PCBs become more active.

• Journal of Advanced Navigation Technology
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• v.23 no.5
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• pp.481-486
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• 2019

Smart Factory requires real-time monitoring and analysis of all process processes for optimal production environment. Monitoring system for data collection from various sensors is necessary to make all production processes automatic. By storing and analyzing the collected data, we can check whether there are any signs of abnormalities in any machine or equipment. Thus, in this paper, an integrated monitoring system for smart factory incorporating a working environment monitoring system and an automatic storage system of measurement values was implemented. By using the automatic storage system of measurement values, it is possible to carry out reliable inspection in any place without misentry. Also, through working environment monitoring system using LoRa, production environments such as temperature, humidity and atmospheric pressure can be monitored in real time.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1243-1248
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• 2018

Metal Powder Metallurgy is a manufacturing technology that makes unique model parts or a certain type of product by using a hardening phenomenon when a powder of metal or metal oxide is put it into a mold and compression-molded by a press and then heated and sintered at a high temperature. Powder metallurgical press equipment is mainly used to make the parts of automobile, electronic parts and so on, and most of them are manufactured using precise servo motor. The intelligent precision servo control powder molding press system which is designed and implemented in this paper has advantages of lowering the price and maintaining the precision by using the mechanical camshaft for the upper ram part and precisely controlling the lower ram part using the high precision servo system. In addition, OPC-based monitoring and process data collection systems are designed and implemented to provide scalability that can be applied to smart manufacturing management systems that utilize Big Data in the future.

• Journal of the Korean Society for Library and Information Science
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• v.32 no.4
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• pp.141-157
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• 1998

The purpose of this study is to increase the effective utilization of library homepages by providing design guidelines. Seven of the library homepages are selected and have their menus of library homepages do share Each library homepage has it's own distinct characteristics, however the library homepages do share five common services : User Service. OPAC, CD-ROM Search, DB Search, Related Sites, Other Services. The result of this study can be used as the basic data for researching of library homepage's interface designs and collection development of electronic information.