• 대한전자공학회논문지TC
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• 제43권10호
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• pp.79-89
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• 2006

TCP는 신뢰성을 보장하는 전송 프로토콜로서 인터넷 등에서 가장 널리 사용되고 있는 전송 방식이다. 하지만 TCP는 유선망에 적합하도록 설계되었기 때문에 무선망에서 TCP를 사용할 경우 성능 저하가 발생된다. TCP의 성능 저하 원인으로는 MAC 계층에서의 무선 매체 경쟁, hidden-terminal 문제와 exposed terminal 문제, 링크 계층에서의 패킷 손실, 불공정성의 문제들과 노드의 이동에 의한 경로 단절시 발생되는 패킷 순서 바뀜 문제와 경로의 단절로 인한 재전송 타이머의 exponential backoff에 의한 대역폭의 낭비 등이 있다. 특히 이동 ad-hoc 망에서는 전송 범위(transmission range)와 간섭범위(interference range)의 불일치로 인해 발생되는 hidden terminal 문제로 인해 동시에 전송할 수 있는 노드의 수가 제한되며 이로 인해 성능저하가 크게 발생된다. 본 논문에서는 IEEE 802.11 기반 이동 ad-hoc 망에서 발생되는 hidden terminal 문제로 인해 노드가 전송을 하지 못하고 CW(contention window)만 크게 증가되는 문제를 해결하기 위한 MAC 알고리즘을 제안한다. 기존의 802.11 MAC의 DCF(distributed coordination function)에서는 전송에 실패할 경우 CW를 지수적으로 증가시키지만 본 논문에서 제안하는 기법은 노드가 전송 실패를 하였을 경우 그 원인에 따라 CW를 적절하게 변화시킴으로 성능 향상을 얻을 수 있다. 이 기법을 사용하면 hidden terminal에 의해 전송을 실패하는 노드에게 공정한 전송 기회를 부여함으로써 TCP 성능 향상을 얻을 수 있음을 시뮬레이션을 통해 보였다.

• 무역상무연구
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• 제20권
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• pp.129-150
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• 2003

Software license agreements, to be useful in the mass market, could not be individually negotiated, and had to be standardized and concise. The software license agreement needs to be presented to the licensee-users in a fashion that would allow for mass distribution of software, also for it to enforceable, that would draw the users' attention to the terms and conditions under which the publisher allowed the use of the software. These needs have been accomplished, with or without fail, through so called the "shrink-wrap licenses" Shrink-wrap licenses purpose to transfer computer softwares to their users by defining the terms and conditions of use of the software without implicating the "first sale doctrine" of the Copyright Act. These shrink-wrap licenses have become essential to the software industry. However, in USA, the law applicable to these licenses has been unclear and unsettled. Courts have struggled to develop a coherent framework governing their enforceability. Meanwhile, the National Conference of Commissioners on Uniform State Laws ("NCCUSL") in USA promulgated the Uniform Computer Information Transaction Act ("UCITA") governing contracts for computer information transaction on July 29, 1999. One clear objective of UCITA was to settle the law governing the enforceability of shrink-wrap licenses. In these respects, this paper first introduces the various forms that shrink-wrap licenses take(at Part II. Section 1.), and explains the main advantages of them(at Part II. Section 2.) Here it shows how shrink-wrap licenses value themselves for both software publishers and users, including that shrink-wrap licenses are a valuable contracting tool because they provide vital information and rights to software users and because they permit the contracting flexibility that is essential for today's software products. Next, this paper describes the current legal framework applicable to shrink-wrap licenses in USA(at Part III). Here it shows that in USA the development of case law governing shrink-wrap licenses occurred in two distinct stages. At first stage, judicial hostility toward shrink-wrap licenses marked such that they were not enforced pursuant to Article 2 of the Uniform Commercial Code. At second stage, courts began to recognize the pervasiveness of shrink-wrap licenses, their indispensability to the rapidly expanding information technology industry, and the urgent need to enforce such licenses in order to maintain low prices for consumers of computer hardware or software, resulting in the recognition of shrink-wrap licenses. Finally, in view of the importance of UCITA, this paper examines how it will affect the enforceability of shrink-wrap licenses(at Part IV). The drafters of UCITA, as well as the scholars and practitioners who have criticized it, agree that it validates shrink-wrap licenses, provided certain procedural protections are afforded to purchasers. These procedural protections include the licensee end-user must (i) manifest his assent to the shrink-wrap license, (ii) have an opportunity to review the shrink-wrap license, (iii) have a right to return the product without costs.

• KDI Journal of Economic Policy
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• 제30권2호
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• pp.61-97
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• 2008

본 연구는 공무원의 전문성 축적을 저해하는 것으로 지속적으로 지적되는 순환보직의 실태를 파악하고 그 개선방안을 제시하는 것을 목적으로 한다. 우리나라 중앙부처 과장급 이상 공무원의 평균재직기간은 1년 남짓으로 매우 짧아 업무의 인수 인계에서 오는 비효율 및 업무공백, 전문성 축적기회의 감소, 책임성 저하, 정책의 일관성 및 연속성 결여 등 여러 문제를 낳으며, 특히 고도의 전문성을 요하는 대외 협상 분야에서 큰 국가적 손실을 낳는 것으로 파악된다. 이의 개선을 위해서는 전문성을 고려하는 보직이동, 전보범위의 축소, 전보제한기간의 강화 등의 조치가 필요하나, 근본적으로 현재와 같은 과도한 순환보직이 연공서열에 기초한 계급제에 기인하므로 장기적으로 공직분류제도를 계급제에서 직위분류제로 전환하고 실적주의적 요소를 강화해야 할 것이다.

• 직업교육연구
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• 제35권6호
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• pp.85-112
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• 2016

이 연구는 2000년부터 2015년까지 평생 직업교육훈련 분야에 게재된 학술논문을 바탕으로 연구자 간의 협력관계 및 네트워크 구조를 살펴보는 데 목적이 있다. 이를 위해 평생 직업교육훈련 분야의 대표적인 학술지인 "평생교육학연구", "직업교육연구", "고용직업능력개발연구"의 연구자 간 사회적 관계와 학술적 영향력의 특성에 대해 파악하고자 NetMiner 4.0을 활용하여 공저자 네트워크 분석을 실시하였다. 분석 결과, 평생 직업교육훈련 분야의 연구 생산성은 멱함수의 형태를 나타내고, 세부 연구 집단이라고 할 수 있는 컴포넌트들이 존재하며 이 네트워크 구조는 좁은 세상의 특성을 나타내고 있었다. 또한 중심성 분석을 통해 연결정도 중심성이 높은 저자는 공동저자로서 다른 연구자들과의 정보 획득과 교류가 활발하여 네트워크상에서 중추적인 역할을 수행하고, 매개 중심성이 높은 저자는 구성원들 사이를 매개해주는 브로커 역할을 하여 여러 집단의 지식과 정보를 전달해주는 통로의 역할을 하고 있음을 알 수 있었다. 과거에 비해 공저자 활동의 증가는 평생 직업교육훈련 분야 연구자 간의 연구협력 기회 및 발전에 긍정적인 영향을 미치는 것으로 해석된다. 그러나 소수의 저자를 중심으로 한 네트워크를 넘어서 다양한 연구자들이 지속적인 연구 생태계를 구성하여 공동연구를 수행하는 성과로 이어지기를 기대한다.

• 한국환경복원기술학회지
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• 제22권1호
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• pp.13-31
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• 2019

Green spaces are recognised for the benefits. They bring to the quality of people's lives. However, since the 1980s there has been a general increase in poorly-managed green spaces. In an attempt to address this issue, green space policy has changed its focus on green space management through the gradual introduction of green space evaluation tools, such as the Green Flag Award (GFA). The GFA, as an established green space evaluation tool in the UK, reflects a shift in policy drivers of green spaces management. However, there is a lack of research investigating the contextualisation between a wide range of policy contexts and such green space evaluation tools (the GFA in this study). The aims of this study are therefore to explore the development of green space evaluation since the late 1990s, with respect to the growth of the GFA and its impact on other evaluation tools across the UK and several countries. To address the aims, this study employs in-depth literature reviews on UK green space policy mainly conducted by government. In addition, case studies are presented, focusing on the GFA and independent green space evaluation tools intrinsically derived from the GFA in the UK's cities and Nordic countries. Results show that based on the awareness of the severity of declining standards of green spaces, newly emerging policy arrangements have been adopted to address negative issues, which affect the standard of green spaces such as the transfer of responsibility for green space management, the implementation of Compulsory Competitive Tendering and ongoing budget cuts. Significantly, the GFA's indicators reflect the emerging changes of economic and social contexts associated with green spaces management where, in particular, the prospect of continuous budget cuts, which encourages communities to become involved in green space management. The GFA has widely contributed to leading such UK's cities and other countries to be able to create their independent green space evaluation tools in different approaches based on stakeholders' (mainly community) involvement in the decision-making process of green space evaluation. In conclusion, this study implies that successful green space evaluation tools do embody the value of green spaces and address drivers of emerging green space management with correspondence to the context of policy arrangements. Importantly, stakeholders have an opportunity to be involved in a partnership in the decision-making process through some green space evaluation tools. It is hoped that for well-managed green spaces this study will contribute valuable knowledge to our existing understanding of green space management in an era of austerity.

• 한국수정란이식학회지
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• 제30권3호
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• pp.149-159
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• 2015

This study was designed to know the possibility in repeat uses of elite donor cows for getting mass production of OPU-derived embryo production (OPU-IVP). Ultrasound transvaginal ovum pick-up (OPU) performed in 6 Korean native cows was aged 4 to 10 years old. The aspiration of immature oocytes for OPU derived embryo was carried out 2 times per week, and OPU-IVP of $1^{st}$ period was carried out 22~48 sessions from each donors. And the break time for OPU-IVP of $2^{nd}$ period after $1^{st}$ OPU from each donors were 2~25 months. The OPU-IVP of $2^{nd}$ period each donors conducted total 15~65 times for 2~8 months by an ultrasonographic, was guided follicular aspiration system. The average numbers of collected oocytes, grade 1 + grade 2(G1+G2) oocytes and cleavage embryo from $1^{st}$ period OPU-IVP were significantly differences between donors (p<0.05). Total collected oocytes of donor D were significantly higher compared with donors of A, B, C, E and F (average 17.0 per session vs. 11.2, 10.1, 8.5, 10.2 and 9.6; p<0.05) and also oocytes of G1+G2 were significantly higher compared with r A and D and subsequently to donors of B, C, E and F (average 7.9 and 8.5 per session vs. 5.0, 2.7, 6.0 and 1.6; p<0.05). Cleavage rate of donor D was significantly higher compared with donors of A, B, C, E and F (average 13.1 per session vs. 10.1, 9.1, 6.9, 8.9 and 6.7; p<0.05). The average numbers of OPU-IVP for $1^{st}$ period was significantly higher from donors of B, D and E than those from donors of A, C and F (average 6.5, 7.1 and 6.5 per session vs. 3.5, 4.2 and 2.8; p<0.05). The possibility investigation of $2^{nd}$ OPU-IVP was carried out after 2~25 months rest periods from $1^{st}$ period OPU session. Total average numbers of collected oocytes, cleavages and blastocyst development rates were significantly higher from $1^{st}$ period OPU compared with $2^{nd}$ period one (p<0.05). The OPU-IVP efficiency by break for more embryo production from elite cow was analysis comparing without rest of donor A, under 6 months rest period as B and over 6 months rest period as C and then the average numbers of collected oocytes, cleavages and blastocysts were significantly higher from A group (11.8, 9.5 and 5.2 per session) than those from B and C groups (7.9, 6.2 and 2.6 vs. 9.2, 7.5 and 3.9, p<0.05), and also C group was significantly higher than B group. In conclusion, $1^{st}$ period OPU-IVP was more efficient compared with $2^{nd}$ period repeated uses of donor, and the break times for additional production of embryo on donor were needed more than over 6 months after $1^{st}$ period OPU-IVP. This repeating uses of elite donor cows given more emphasis for getting the opportunity on mass production of elite cow OPU-IVP embryo should be increased G1+G2 possibility of genetic improvement of livestock within short period.

• 핵의학기술
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• 제13권3호
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• pp.31-42
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• 2009

최근 PET/CT가 급격하게 증가하면서 의료기관 사이에 영상의 이동도 증가하고 있다. 이에 서로 다른 의료기관 간의 시스템 별 표준섭취계수 차이를 반영하기 위하여 1 Bed에서 표준섭취계수, 슬라이스 내의 표준섭취계수 변화율과 측정시간에 따른 표준섭취계수를 정량적으로 비교할 수 있는 팬텀을 이용한 비교측정이 필요하다. 본 연구에서는 임상에서 사용하는 다양한 PET/CT 시스템의 표준섭취계수 차이에 대한 연구를 통하여, PET/CT 영상의 표준화섭취계수의 신뢰성을 확보하고자 하였다. 대한민국 전국에 분포되어 의료기관에 설치된 PET/CT 장비 10대를 대상으로 하였으므로, 정확한 방사능 산출을 위하여, 한국표준과학원의 검출기로 검증을 통하여 실험하였다. NEMA PET $Phantom^{TM}$의 내부구조물을 제거하고 $^{18}F$-FDG 1 mCi를 6,000 mL 증류수에 균일하고 분포하도록 마그네틱 스터러와 마그네틱 바의 회전력으로 희석하여, 팬텀에 주입하였다. 주입 후 60분, 70분, 80분, 90분, 100분, 110분, 120분에 3분간 영상을 획득하고, 관심영역 $200\;cm^2$에 대하여 분석하였으며, 유용성 확인을 위하여 임상환자를 대상으로 교정표를 산출하였다. 1 Bed에서 표준섭취계수, 슬라이스 내의 표준섭취계수 변화율, 측정시간에 따른 표준 섭취계수 변화율과 함께 표준섭취계수의 변이계수가 -11.0~9.90%로 국제적으로 통용되는 기준인 ${\pm}10%$를 1개의 장비를 제외하고 모두 만족하였다. 또한, 시스템 별 평균 표준섭쉬계수 차이를 이용하여 0.803~1.246으로 이루어진 교정표를 도출하였고, 정상인을 통한 임상 적용에서 선형회귀분석을 통하여 유의함을 확인하였다. 본 연구를 통하여 PET/CT 장비간의 표준섭취계수 차이를 교정표를 이용하여 정량적으로 비교할 있는 근거를 제시한다면 정확한 진단에 도움이 되며, 아울러 이에 대한 세계적 기준이 명확하지 않기에 유사 연구에 도움이 되리라 사료된다.

• 정보학연구
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• 제1권2호
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• pp.81-102
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• 1998

현대사회를 무한경쟁시대라 말한다. 이러한 국내외 경영환경변화에 도전하기 위하여 조직도 새로운 변화를 해야하며 변화를 시도하고자 하는 경우에는 그 변화의 주체가 원하든 원하지 않든 간에 조직내에 갈등이 수반되기 마련이다. 변화에 따라 크고 작은 갈등해소에 관심이 있어야 하며 갈등을 생산적이고 창의적으로 관리하여 조직의 새로운 활력과 발전의 기회로 삼아야 할 것이다. 또한 갈등은 인간으로 구성된 조직에서는 목표와 욕구에 따른 다양한 갈등이 존재하여 갈등으로부터 자유로울 수 없으며 조직과 조직 그리고 인간과 조직간의 공존이라는 현대사회의 특징을 감안할 때 피할 수 없는 숙명과 같은 것이다. 그러므로 갈등을 관리한다는 것은 조직 발전의 좌표로써 매우 중시되며 조직의 적극적인 영향을 발휘하도록 갈등을 감소시키거나 증가시키는 행동을 할 때 갈등자체를 합리적이고 효율적으로 관리해야 한다는 것에 유의할 필요가 있다. 따라서 조직행동론 관점에서 조직성과 및 조직 유효성에 직무만족과 관련하여 개인의 갈등이 조직 내 이직과 결근율 더 나아가서 조직전체의 생산성에 미치는 영향이 매우 크다는 사실과 조직관리자는 구성원의 갈등해소와 직무만족을 위하여 갈등관리 방안을 다음과 같은 3가지 방안을 강구하여야 할 것이다. 결과적으로 개인갈등에 따른 조정방안을 중심으로 개인갈등관리 및 직무만족과 조직 유효성 그리고 생산성 향상에 보다 노력하는 것과 조직관리자와 구성원들은 조직 내 갈등을 문제가 아닌 새로운 발전의 계기와 문제 해결의 한 부분으로 인식하여 새로운 이노베이션을 창출하게 끔 갈등관리의 방향을 제시하여야 할 것이다.% (P<0.05)로 여성요인 환자에서 유의하게 높았다. 결론적으로 세포질내 정자주입술 후 수정률과 발생된 배아의 발생률은 광학현미경하에서 관찰한 난자의 상태와 상관관계가 없는 것으로 사료되며, 세포질내 정자주입술 후 난자의 퇴화율은 난자 세포막의 탄력성과 상관관계가 있는 것으로 생각된다.rine 또는 autocrine조절물질로 작용하여 GH 분비 외에도 뇌하수체 전엽 세포들의 분화와 분열등에 관여함을 시사한다..3 unit의 잔존활성을 보였으나 중심온도가 9$0^{\circ}C$와 10$0^{\circ}C$일 때 잔존활성은 측정되지 않았다.>에서 뚜렷한 효과를 나타내었다.비율이 높은 반면 Malaysia 거주자들은 중국음식, 만두 및 면류의 이용이 비교적 많은 편이었다. 이상의 결과를 종합해 보면 외국에 거주하면서 한국의 전통적인 특성을 간직하고자 하는 의식을 가지고 있음을 볼 수 있으며 하루 세끼의 식사형태에서 밥을 중심으로 하는 비율은 국내 보다 크게 낮았지만 여전히 다른 식사형태 보다 높은 것을 알 수 있다. 한국 고유의 식문화 특성을 가지면서 거주지역의 식품생산 및 사회 문화적 특성에 영향을 받음으로써 거주국의 식품, 식사 형태, 조리방법을 도입하는 등 부분적으로 변화가 진행되고 있음을 확인 할 수 있었다.가장 시급한 개선점이라고 생각된다. 따라서 효과적인 급식운영을 하기 위해서는 학교식당은 맛, 다양한 메뉴의 식단, 위생, 가격의 저렴 등을 통해서 급식대상자들이 만족한 급식을 할 수 있도록 체계적인 관리 및 운영을 통해 적극적으로 개선해 나가야 할 것으로

• 지식경영연구
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• 제17권2호
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• pp.131-163
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• 2016

The purpose of this study is to empirically analyze how social comparative learning of forum participants affects learning effects with an emphasis on participants' characteristics. As today's society is changing at a fast pace, the desire for new knowledge and information has grown accordingly. To quench this thirst for knowledge and information, seminars, symposiums, conferences, forums, conventions, exhibitions, and more are taking place as part of knowledge sharing events across the world. Also, the increased need for knowledge and information exchange has led the development and growth of the convention industry and Meetings, Incentives, Conferences, and Events (Exhibitions)(MICE) industry. Especially, forum is a type of event which invites professionals and specialists to discuss diverse topics and share their knowledge and experience with the audience. The participants utilize it as an opportunity to get close to information providers and enjoy the pleasure of knowledge exchange. However, there have been few empirical analyses on who the participants are, why they attend forum, how they pick up and learn new information and knowledge, and what kinds of learning effects they achieve after the event. This paper is to analyze how social comparative learning of the forum's participants influences learning effects based on Albert Bandura's Social Learning Theory (1977, 1997, 1982. 2001) and Leon Festinger's Social Comparative Theory (1950, 1954). By dividing the participants into two groups, one with high level of self-efficacy and the other with low level of self-efficacy, we have examined the differences in learning effects between the two groups using them as moderating variables. This study was conducted in 'MBN Y Forum 2016,' which is one of the most representative knowledge exchange forums of South Korea. An online survey was distributed out and, 1,307(39.2%) out of the total participants of 3,338 have completed the survey. The survey included questions about whether the participants have gained positive or negative motivations by comparing themselves to the speakers (upward comparison learning) and other participants (lateral comparison learning). The results have shown the quality of messages that the speakers are presenting as knowledge providers is the most significant factor that acts on learning effects. Particularly, the participants had higher levels of self-efficacy and self-esteem than average people. They had a clear goal to learn from the speakers (upward comparison) and received positive motivations from them. In other words, no negative learning effects had been found. This presents a managerial implication that having a qualified speaker is necessary for a forum to be successful. On the other hand, the results from the comparison with the other participants (lateral comparison) were different. The participants were likely to compare themselves to the other participants through observational learning. They could compare listening attitudes, language skills, or capabilities to ask a question. The results have showed the participants received positive motivations from the lateral group but at the same time were jealous of abilities of the others. When the quality of a question by a participant is not good enough, it can have a negative influence on the participants' learning effects. The first group with high levels of self-efficacy and self-esteem had no correlation to negative learning effects from the speakers. They rather had a strong desire to learn from the speakers. On the contrary, the participants perceived the lateral group as a learning subset and competitor. The second group with low levels of self-efficacy and self-esteem saw the quasi-group as a rival. This presents that the individual learning effects can be different depending on the participants' characteristics.

• 한국중재학회지:중재연구
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• 제17권2호
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• pp.167-187
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• 2007

As Korea has reached a free trade agreement with the United States of America, it is required to provide an appropriate procedure to ".kr" domain name disputes based on the principles established in the Uniform Domain Name Dispute Resolution Policy(UDRP). Currently, Internet address Dispute Resolution Committee(IDRC) established under Article 16 of the Act on Internet Address Resources provides the dispute resolution proceedings to resolve ".kr" domain name disputes. While the IDRC's proceeding is similar to the UDRP administrative proceeding in procedural aspects, the Domain Name Dispute Mediation Policy that is established by the IDRC and that applies to disputes involving ".kr" domain names is very different from the UDRP for generic Top Level Domain (gTLD) in substantial aspects. Under the Korea-U.S. Free Trade Agreement(KORUS FTA), it is expected that either the Domain Name Dispute Mediation Policy to be amended to adopt the UDRP or the IDRC to examine the Domain Name Dispute Mediation Policy in order to harmonize it with the principles established in the UDRP. It is a common practice of cybersquatters to warehouse a number of domain names without any active use of these domain names after their registration. The Domain Name Dispute Mediation Policy provides that the complainant may request to transfer or delete the registration of the disputed domain name if the registrant registered, holds or uses the disputed domain name in bad faith. This provision lifts the complainant's burden of proof to show the respondent's bad faith because the complainant is only required to prove one of the three bad faiths which are registration in bad faith, holding in bad faith, or use in bad faith. The aforementioned resolution procedure is different from the UDRP regime which requires the complainant, in compliance with paragraph 4(b) of the UDRP, to prove that the disputed domain name has been registered in bad faith and is being used in bad faith. Therefore, the complainant carries heavy burden of proof under the UDRP. The IDRC should deny the complaint if the respondent has legitimate rights or interests in the domain names. Under the UDRP, the complainant must show that the respondent has no rights or legitimate interests in the disputed domain name. The UDRP sets out three illustrative circumstances, any one of which if proved by the respondent, shall be evidence of the respondent's rights to or legitimate interests in the domain name. As the Domain Name Dispute Mediation Policy provides only a general provision regarding the respondent's legitimate rights or interests, the respondent can be placed in a very week foundation to be protected under the Policy. It is therefore recommended for the IDRC to adopt the three UDRP circumstances to guide how the respondent can demonstrate his/her legitimate rights or interests in the disputed domain name. In accordance with the KORUS FTA, the Korean Government is required to provide online publication to a reliable and accurate database of contact information concerning domain name registrants. Cybersquatters often provide inaccurate contact information or willfully conceal their identity to avoid objection by trademark owners. It may cause unnecessary and unwarranted delay of the administrative proceedings. The respondent may loss the opportunity to assert his/her rights or legitimate interests in the domain name due to inability to submit the response effectively and timely. The respondent could breach a registration agreement with a registrar which requires the registrant to submit and update accurate contact information. The respondent who is reluctant to disclose his/her contact information on the Internet citing for privacy rights and protection. This is however debatable as the respondent may use the proxy registration service provided by the registrar to protect the respondent's privacy.