• 전자통신동향분석
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• 제38권6호
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• pp.128-136
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• 2023

Lithium accounts for only 0.0017% of the earth crust, and it is produced in geographically limited regions such as South America, the United States, and China. Since the first half of 2017, the price of lithium has been continuously increasing, and with the rapid adoption of electric vehicles, lithium resources are expected to be depleted in the near future. In addition, economic blocs worldwide face intensifying scenarios such as competition for technological supremacy and protectionism of domestic industries. Consequently, Korea is deepening its dependence on China for core materials and is vulnerable to the influence of the United States Inflation Reduction Act. We analyze post-lithium secondary battery technologies that rely on more earth-abundant elements to replace lithium, whose production is limited to specific regions. Specifically, we focus on the technological status and issues of sodium-ion, zinc-air, and redox-flow batteries. In addition, research trends in post-lithium secondary batteries are examined. Post-lithium secondary batteries seem promising for large-capacity energy storage systems while reducing the costs of raw materials compared with existing lithium-based technologies.

• 디지털콘텐츠학회 논문지
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• 제9권1호
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• pp.61-67
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• 2008

본 논문에서는 IEEE 802.11 WLAN의 MAC인 DCF의 성능을 개선하는 알고리즘을 제안하고 이를 시뮬레이션으로 분석한다. IEEE 802.11 WLAN의 MAC에서는 데이터 전송을 제어하기 위한 방법으로 DCF와 PCF를 사용하며, DCF의 경우 CSMA/CA를 기반으로 한다. CSMA/CA는 스테이션간의 충돌을 줄이기 위해서 임의의 Backoff time을 각 스테이션의 CW(Contention Window) 범위에서 결정한다. 스테이션은 패킷 전송 후 충돌이 발생하면, 윈도우 크기를 두 배로 증가시키며, 패킷을 성공적으로 전송하면 윈도우 크기를 최소 CW로 감소한다. DCF는 경쟁 스테이션이 적은 상황에서는 비교적 우수한 성능을 보이나 경쟁 스테이션의 수가 많은 경우 처리율, 지연 관점에서 성능이 저하되는 문제점이 있다. 본 논문에서는 패킷 전송 후 충돌이 발생하면 윈도우 값을 최대 CW로 증가시키고 패킷의 정상적인 전송후에는 윈도우 값을 서서히 감소함으로써 현재 WLAN의 망 상태정보를 계속 활용함으로써 패킷 충돌 확률을 낮추는 알고리즘을 제안한다. 제안하는 알고리즘의 효율성을 입증하기 위해 시뮬레이션을 수행하여 그 타당성을 제시하였다.

• 한국정보통신학회논문지
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• 제6권8호
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• pp.1200-1205
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• 2002

세계무역기구(WTO)의 기본통신협상에 따라 다수의 통신사업자가 통신시장에 진입하고, 특히, 1999년부터는 공기업들도 자회사를 통해 기간통신사업 허가를 받아 자가통신설비를 활용할 수 있도록 규제가 완화되어 왔다. 정보통신서비스사업 진출입에 대한 규제완화와 국내 정보통신 산업의 급속한 발달에 힘입어 일부 공기업을 비롯한 자가망 보유 회사들은 기존 통신사업자들의 통신망이 충분히 설치된 이후에도 자체 수요에 대처한다는 명분을 앞세워 통신망 분야에 투자를 확대하고 있다. 이와 같은 자가전기통신설비 구축은 국내 통신사업구도에도 커다란 변수로 등장하고 있으며 외국 기업에도 영향을 미칠 것으로 예상된다. 그러므로 자가통신망에 대한 국가적 정책은 정보통신망의 효율적 구축, 중복·과잉투자 방지, 공정경쟁 보장, 회계분리, 자회사 설립, 통신사업 구조조정, 국가경쟁력 강화 등 여러 측면에서 종합적으로 고려되어야 한다. 따라서 본 연구에서는 자가전기통신설비 현황 및 실태와 자가전기통신설비 관련 정책을 살펴보고, 외국의 자가통신망 실태와 관련 법·제도 둥을 비교·분석하여 자가전기통신설비에 관련한 효율적인 개선 방안을 제시하였다.

• 보건행정학회지
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• 제8권2호
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• pp.25-57
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• 1998

In order to assess the attractiveness of the hospital industry, the competitive environment of the industry was analyzed. With the employment of Michael Porter's five forces model' the deciding factor was examined and applied to evaluate the intensity of the competitiveness in the hospital industry, and then the structure and attractiveness in hospital industry was assessed. The subject of this study was hospitals that have over 500 beds. Main findings are as follows. 1. Out of 5 factors deciding competitiveness, the pressure from newly opened hospitals and the competition between existing hospitals, were both high in intensity; this makes hospital industry less attractive. The pressure from the substitutes and the pressure from the negotiating power of consumers and suppliers were low; this makes hospital industry more attractive. 2. Overall intensity of competitive pressure pressure for existing hospital industry that have over 500 beds was rather low, consequently the attractiveness of the industry was evaluated quite high. These findings, however, were not solid enough to endorse the attractiveness of the industry. 3. It was understood that future industry would have bigger pressure/ competition so that the attractiveness for the relevant hospital industry would be decreased. This study has its limitations. As the evaluation of competitive factor was not grounded on quantitative data, its objectivity could be questioned. Also, the overall result of each factors could be distorted as it was calculated with same weight against individual factor. This study has its significance in that the specific hospital group was viewed as one industry, and its attractiveness as a potentially profitable industry in which worth investing was estimated, with all factors considered. With this key result, hospitals industustry could work out a plan to enhance the status of hospitals, allowing hospitals to get assistance in making strategic decisions such as mergers, cooperations, and new establishments.

• 한국산학기술학회논문지
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• 제9권2호
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• pp.388-394
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• 2008

본 논문에서는 IEEE 802.11 WLAN(Wireless LAN)의 MAC(Medium Access Control)인 DCF(Distributed Coordination Function)의 성능을 개선하는 알고리즘을 제안하고 이를 시뮬레이션으로 분석한다. IEEE 802.11 WLAN의 MAC에서는 데이터 전송을 제어하기 위한 방법으로 DCF와 PCF(Point Coordination Function)를 사용하며, DCF의 경우 CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance)를 기반으로 한다. DCF는 경쟁 스테이션이 적은 상황에서는 비교적 우수한 성능을 보이나 경쟁 스테이션의 수가 많은 경우 처리율, 지연 관점에서 성능이 저하되는 문제점이 있다. 본 논문에서는 패킷 전송 후 충돌이 발생하면 윈도우 값을 최대 CW로 증가시키고 패킷의 정상적인 전송 후에는 윈도우 값을 서서히 감소함으로써 현재 WLAN의 망 상태정보를 계속 활용함으로써 패킷 충돌 확률을 낮추는 알고리즘을 제안한다. 제안하는 알고리즘의 효율성을 입증하기 위해 시뮬레이션을 수행하여 그 타당성을 제시하였다.

• 경영과정보연구
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• 제5권
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• pp.139-160
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• 2000

Todays our private universities have been facing with serious survival competition according to the opening of education market, the diminishment of college voluntarists and the increase of education supply. In coming the beginning of the year of 2000, though the equal formula. 'The fixed number of students of universities = The number of graduates of high schools' will he formed, even though the tendency of the fixed number of students of universities is maintained as it is, and it has been expected the unlimited competition would be unvaoidable, so private universities and private junior colleges which are weak in financial power are roaring the crisis consciousness that they may have to close doors before making every effort. Based on such presentation of problem as its study object, the range of study is limitted to the educational financial portion related to higher education field. Especially, the financial portion of private universities of higher educational field is discussed in priority. Besides, the present status of financial condition of our universities was portionally compared with that of in the advanced nations. It is true that pursuing the academic superiority of university education in our country, and attaining object of university as well as developing reflection in future should stand side by side. Therefore, payment of fee, supporting subsidy, etc. is attached too much importance to the financial problem. In our country, the financial allotment is attached too much importance to national universities. This is against the principle of equity to the tax payers, and equality of opportunity, so the level of supporting national funds should be upward formed and supported from 1.0% to higher than 20%. In conclusion, our private universities should adopt as many alternatives of rationalization of finance as possible, such as securing lots of funds and subsidies, and rationalized management of finance, and ensuring finance according to the increasing number of students after university specialization, etc.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 추계종합학술대회
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• pp.63-69
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• 2002

1994년부터 시작된 세계무역기구(WTO)의 기본통신협상에 따라 다수의 통신사업자가 통신시장에 진입하고, 특히, 1999년 1월부터는 공기업도 자회사를 통하여 기간통신사업 허가를 받을 수 있게 되는 등 자가통신설비와 관련된 규제제도는 최근까지 계속적으로 완화되어 왔다. 이와 같은 규제완화와 국내 정보통신 산업의 급속한 발달에 힘입어 일부 공기업을 비롯한 자가망 보유 회사들은 통신사업자들의 통신망이 충분히 설치된 이후에도 자체 수요에 대처한다는 명분을 앞세워 통신망 분야에 확대투자를 하여 통신사업의 진입을 직ㆍ간접적으로 모색하고 있다. 이와 같은 자가전기통신설비 구축은 국내 통신사업구도에도 커다란 변수로 등장하고 있으며 외국 기업에도 영향을 미칠 것으로 예상된다. 그러므로 자가 통신망에 대한 국가적 정책은 정보통신망의 효율적 구축, 중복ㆍ과잉투자 방지, 공정경쟁 보장, 회계분리, 자회사 설립, 통신사업 구조조정, 국가경쟁력 강화 등 여러 측면에서 종합적으로 고려되어야 한다. 따라서 본 연구에서는 자가전기통신설비 현황 및 실태와 자가전기통신설비 관련 정책을 살펴보고, 외국의 자가통신망 실태와 관련 법ㆍ제도 둥을 비교ㆍ분석하여 자가전기통신설비에 관련한 효율적인 개선 방안을 제시하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1998년도 21세기 한반도 농업전망과 대책(한국작물학회.한국육종학회 공동주관 심포지움 회보)
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• pp.336-352
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• 1998

The horticultural seed industry has made great progress in the last fifty years of its history after the independence of this country. The industry has accomplished self-sufficiency in major vegetable seeds and has even gained international competitive edge in certain crop seeds, particularly in hybrid cultivar development. However, the industry is facing a crisis at present coming from excessive competition among the domestic seed companies as well as the foreign currency crisis of the country. Several major seed companies have already been acquired by multinational corporations. Many people in the country as well as agriculturists are concerned about this situation. Although it is true that the industry is undergoing hard times, this crisis can be turned into a chance for making new progress depending on the joint efforts of the groups responsible, i.e., private companies, public institutions, and policy makers. Therefore, we have to turn this crisis into an opportunity for self-reform and progress. We should not be discouraged or give up. We Propose some ideas for the Progress of the seed industry. Public institutions and policy makers should do such things in cooperation as 1) training human resources for future breeders, 2) securing a wide range of genetic resources and improvement of the management system, 3) basic science research including biotechnology, 4) releasing breeding stocks from germplasm enhancement through use of exotic accessions, 5) support for breeding region- or use-specific cultivars, and 6) collection of foreign agricultural information for breeding cultivars for overseas markets. Eventually the responsible group for the final development of commercial cultivars, production, sales and management is private companies. Therefore, private companies also should have to do their best to develop competitive cultivars with a missionary spirit and endeavor for both domestic and overseas markets in cooperation with public institutions. Management based on competition, professionalism and rationalism is also urged. We are going to conclude with optimism that we can make a new vault of progress once the private and public sectors closely cooperate for the development of Korean horticultural seed industry by overcoming this crisis.

• 한국융합학회논문지
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• 제10권6호
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• pp.147-155
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• 2019

글로컬(Glocal) 시대는 국가 단위보다는 도시 중심의 지역 발전 경쟁이 심화되고 있다. 도시는 이미지의 생산과 소비를 통해 지역 발전의 가치를 창출한다. 이는 긍정적 도시 이미지를 통해 그 도시만의 매력을 높이는 것이 지역 발전 경쟁에서 우위를 선점할 수 있음을 시사한다. 이러한 배경에서 본 연구는 평택시의 도시 이미지 개선을 위한 홍보 디자인 개발을 목적으로 평택시가 추구하고자 하는 이미지 가치와 발전방향의 제시함으로써 평택시의 긍정적 이미지 개선에 기여하고자 하였다. 연구의 내용으로는 도시 이미지의 개념과 필요성에서 도시 홍보의 효율적인 수단으로서 도시 이미지를 인식하였다. 이에 따라 평택시에 대한 현황 분석과 이미지에 대한 설문조사를 실시하였다. 단계별 진행으로 시정홍보 디자인 개발을 통한 결과물과 활용방안 등을 매뉴얼에 제시하여 평택시의 긍정적 이미지를 개선하는데 기여하고자 한다.

• Journal of Ecology and Environment
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• 제45권4호
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• pp.237-254
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• 2021

Background: Some of the introduced alien species introduced settle, multiply, and spread to become invasive alien species (IAS) that threaten biodiversity. To prevent this, Korea and other countries legally designate and manage alien species that pose a risk to the environment. Moreover, 2160 alien species have been introduced in South Korea, of which 1826 animals and 334 plants are designated. The inflow of IAS can have negative effects such as ecosystem disturbance, habitat destruction, economic damage, and health damage to humans. To prevent damage caused by the inflow of IAS in advance, species that could potentially pose a risk to the environment if introduced in South Korea were designated as alert alien species (AAS). Results: The designation criteria were in accordance with the "Act on the Conservation and Use of Biological Diversity" and the "Regulations on the Ecological Risk Assessment of AAS and IAS" by the National Institute of Ecology. The analysis result of risk and damage cases indicated that mammals affect predation, competition, human economic activity, virus infection, and parasite infection. Birds have been demonstrated to affect predation, competition, human economic activity, and health. It was indicated that plants intrude on the ecosystem by competing with native species with their high-population density and capacity to multiply and cause allergic inducement. Interestingly, 300 species, including 25 mammals, 7 birds, 84 fishes, 28 amphibians, 22 reptiles, 1 insect, 32 spiders, 1 mollusk, 1 arthropod, and 99 plants, are included in the list of AAS. Conclusions: AAS designation plays a role in preventing the reduction of biodiversity by IAS in South Korea and preserving native species. Moreover, it is determined to provide considerable economic benefits by preventing socio-economic losses and ecological damage.