• Magazine of the Korea Concrete Institute
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• v.11 no.1
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• pp.183-190
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• 1999

This paper investigated the possibility of appling to concrete through fundamental experiment for garnet, which was industrial wastes generated in kyung pook region, in aspects of development of new materials and recycling of industrial wastes due to shortage of natural resources. Consequently, garnet powder showed the possibility of admixture as showed in the chemical composition because the content of silica and alumina in relation to pozzolanic activity was about 50%. The time of setting was more or less diminished as the increasing of replacement ratio of garnet. In flow test, flow values tended to increase to some degree as the increasing of replacement ratio of garnet. Therefore, application of garnet was expected to improve the workability of concrete. The compressive strength of mortar replaced by garnet was respectively increased as compared with plain mortar and the maximum strength was showed in replaced by 10%, however a little different to the change of W/B ratio. Also, the possibility of admixture to reduce the amount of cement and to improve the property of concrete was showed as the strength of mortar replaced by garnet was comparable to that by existing admixture(silica fume, fly-ash).

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.673-675
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• 2004

애드혹 네트워크지(ad hoc network)는 기존 유선 환경에서의 인프라가 없이도 각 무선 노드들이 필요한 상황에 맞게 동적으로 네트워크를 구성할 수 있는 무선 노드들의 집합을 말한다. 애드혹 네트워크는 제한된 파워 공급, 노드의 이동성으로 인한 잦은 경로 재설정 등으로 동적인 토폴로 구조를 갖는다. 유선 네트워크와 다른 이러한 특징들 때문에 기존의 라우팅 알고리즘을 수정한 다양한 라우팅 알고리즘이 등장 하였다. 그 중 multi-rate을 고려한 AODV 라우팅 기법은 기존의 single-rate을 이용하는 것보다 전송 연 시간의 감소, 패킷 처리율 증가와 같은 장점을 갖는다. 그러나 새로운 경로를 설정함에 있어서 네트워크 전반에 걸쳐 제어 메시 의 수가 증가하는 단점이 있다. 애드혹 네트워크에서 제어메시 는 데이터 패 킷보다 전송시 우선 순위를 가 기 때문에 제어메시 의 증가는 전체적인 패킷 처리율을 감소시킨다. 이러한 문제점을 해결하고자 본 논문에서는 경로 복구 매커니즘의 확장 및 검색지(expanding ring search)알고리즘에서 제어 메시 의 수를 효과적으로 줄일 수 있는 방법을 제안하였다. 기본 아이디어는 단절 이전의 정보를 이용하여 선택적으로 제어 메시 를 브로드 캐스트하는 것이다. NS-2로 제안 알고리즘을 시뮬레이션 한 결과. 기존방법에 비해 20%이상 제어 메시 가 감소하였고, 패킷 전송 연에 대해서는 최대 10%의 감소율을 보여 기존 방법보다 좋은 성능을 보임을 확인할 수 있었다.

• Proceedings of the Optical Society of Korea Conference
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• 2000.08a
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• pp.184-185
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• 2000

1 차원 자성 포토닉 결정은 원하는 파장에서 큰 페러데이 회전각과 투과율을 얻을 수 있기에 아주 흥미롭다. 두 종류의 유전체 층(S: $SiO_2$, T:T $a_2$ $O_{5}$)을 주기적으로 적층한 구조에, Bi를 다량 치환한 가네트 박막(M:B $i_{1.07}$ $Y_{1.93}$F $e_{5}$ $O_{12}$)을 결함층으로 삽입한 (A/B)$_{k}$ M/(B/A)$_{k}$ 의 구조를 갖는 1차원 자성 포토닉 결정의 자기 광학 특성을 수치해석하였다. 가시광과 적외선 영역에서 1차원 자성 포토닉 결정의 자성체 층의 두께( $d_{M}$ )와 유전체 층의 적층수(k)를 변화시키며, 투과율(T)과 페러데이 회전각($ heta$$_{F}$ ) 및 성능지수(Q)를 조사하였다. (중략). (중략)(중략)

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.800-802
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• 2010

최근 기업가정신 관련 선진연구동향을 살펴보면, 네트워크를 원천으로 한 자원자본인 사회적 자본과 조직기업가정신이 벤처기업에게 다양한 자원과 정보에 접근할 수 있는 중요한 역할을 한다는 연구들이 주목받고 있다. 본 연구는 동태적 역량의 관점에서 사회적 자본과 조직기업가정신이 기업성과에 미치는 영향에 대해 탐색적으로 각각 살펴보았다. 이를 위해 국내 171명의 벤처기업 기업가를 대상으로 설문을 실시하였으며, 실증분석 결과는 다음과 같다. 첫째, 네트워크에 근거한 자원 자본인 사회적 자본은 조직기업가정신에 유의한 영향을 미치는 것으로 나타났다. 둘째, 사회적 자본은 벤처기업의 기업성과에도 유의한 영향을 미치는 것으로 나타났다. 셋째, 조직기업가정신은 기업성과에 유의한 영향을 미치는 것으로 밝혀졌다. 따라서 본 연구는 자원조달관점에서 태생적인 불리함을 지니고 있는 벤처기업에 있어 사회적 자본과 조직기업가정신이 기업성과에 중요한 영향을 미친다는 시사점을 제공한다. 아울러 변화와 혁신의 요구를 상대적으로 치열하게 경험하고 있는 벤처기업은 외부 자원을 활용할 수 있는 사회적 자본의 축적과 조직기업가정신 활동을 적절히 수행할 때 비로소 지속가능한 경영을 할 수 있을 것이라는 시준점을 얻었다.

• Journal of Service Research and Studies
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• v.6 no.4
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• pp.15-34
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• 2016

The purpose of this study is to examine the effects of social entrepreneurship on organizational performance and to identify network moderating effects on social entrepreneurship and organizational performance. Data collected from 189 employees working in social enterprises were analyzed by using SPSS 18.0 program. Results are as follows: First, innovativeness, proactiveness, and social value orientation which were sub-factors of social entrepreneurship had positive effects on social performance. Second, proactiveness, risk-taking, and social value orientation which were sub-factors of social entrepreneurship had positive effects on economic performance. Third, the network significantly moderated the effects on innovativeness, proactiveness, social value orientation which were sub-factors of social entrepreneurship, and social performance. Fourth, the network significantly moderated the effects on proactiveness which was a sub-factor of social entrepreneurship, and economic performance. These results exhibited that the social entrepreneurship was effective to increase the organizational performance by activating the network and proposed a useful approach for further studies as an investigation method.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.3
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• pp.87-96
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• 2016

The purpose of this study is to analyze the effect of entrepreneurs' social network on entrepreneurial performance and the moderate effect of entrepreneurial experience on the relationship between social network and entrepreneurial performance. Empirical study was conducted using survey questionnaires for entrepreneurs and path analysis was conducted using PLS method. The result of this study showed that tie strength of entrepreneurs' social network was related to productivity but creativity while network diversity was positively related to creativity but productivity. The moderate effect of entrepreneurial experience was significant on the relationship between tie strength of social network and entrepreneurial performance. This study implies the importance of entrepreneurs' social network and experience and suggests an effective social network structure for entrepreneurial success.

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.61-65
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• 1996

This study was carried out to determine the effect of fruit-set position and number of fruit set per plant on yield and quality including netting in "Super VIP" melon cultivated in spring season. 1) In training system of one fruit per plant, index of netting was acceptable, regardless of the node position of fruit-set. The higher node order of fruit set was, the heavier, longer, bigger in diameter the fruit set was, and the thicker the flesh was. However, soluble suger content and storability was decreased with increased node order. 2) In training system of two fruit per plant, the higher the fruit-set position in node order was, the better the netting index, fruit quality including fruit weight, length, diameter, and thickness of flesh were, but there was no difference in storability. 3) Fruits produced by one-fruit-per-plant training were superior to those produced by two-fruit-per-plant training in maker quality including netting, sugar content, stcrability. The fruit set on 12th node in one-fruit-per-plant training were the best in market quality. 4) Yield was increased by two-fruit-per-plant training.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.5
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• pp.193-198
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• 2004

Using the $PbO-B_2O_3-Bi_2O_3$ flux system, $(TbBi)_3(FeAIGa)_5O_{12}(TbIG)$, $(EuBi)_3(FeAIGa)_5O_{12}(EuIG)$ and $(EuTbBi)_3(FeAIGa)_5O_{12}(EuTbIG)$ films were grown on $(GdCa)_3(GaMgZr)_5O_{12}(SGGG)$ substrates by the liquid phase epitaxy (LPE). The saturation magnetization of the grown TbIG, EuIG and EuTbIG films was about 150, 950 and 125 Oe, respectively. The TbIG films resulted in the single magnetic domain while the EuIG and EuTbIG films were observed to be the multi magnetic domains by magnetic force microscope (MFM).

• Journal of the Korean Ceramic Society
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• v.39 no.6
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• pp.589-593
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• 2002

The single crystalline thick fi1ms of Bi:Y$_3$Fe$_{5}$ $O_{12}$(Bi:YIG) were grown on (GdCa)$_3$(GaMgZr)$_{5}$ $O_{12}$(SGGG) by Liquid Phase Epitaxy (LPE). The changes of lattice mismatch and Bi concentration were investigated in the thick film growth as a function of PO/Bi$_2$ $O_3$ molar ratio, with keeping constant of substrate rotation speed, supercooling and growth time. It was grown that the lattice constant of the garnet single crystalline thick films and Bi content increased with decreasing of PO/Bi$_2$ $O_3$ molar ratio. Bi concentration decreased with increasing of the film thickness.

• Journal of the Korean Magnetics Society
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• v.10 no.3
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• pp.99-105
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• 2000

One dimensional magneto-photonic crystal having structure of (A/B)$^{k/W}$(B/A)$^{k}$ , where M is a magnetic layer of highly Bi-substituted iron garnet, A and B are dielectric layers of $SiO_2$ and T $a_2$O$_{5/}$, and k is the stacking number of the dielectric layers, has been numerically analyzed as a function of the thickness (d$_{M}$) of M (1∼535 nm) and the stacking numer of k (5∼15). The transmittance, Faraday rotation, and figure of merit of the magneto-photonic crystal have been investigated both in the visible and infrared wavelengths. A factor of several and several tens greater Faraday rotation and figure of merit have been obtained compared to the single layer of M, at many localized modes. In the visible the maximum figure of merit of 0.15 was obtained ( = 720 nm) when k = 11 and d$_{M}$ = 375 nm with T : 0.54, $\theta$$_{F}$ = 8.13$^{\circ}$, which was a factor of 30 greater than that of single garnet layer. Much greater maximum figure of merit, 0.285, was obtained in the infrared ( = 1114 nm) when k = 11 and d$_{M}$ = 800 nm with T = 0.66, $\theta$$_{F}$ = 18$^{\circ}$, which was a factor of 100 greater than that of single garnet layer.