• 한국지능정보시스템학회:학술대회논문집
• /
• 한국지능정보시스템학회 2005년도 공동추계학술대회
• /
• pp.183-192
• /
• 2005

Recently, community computing has been proposed for group formation and group decision-making. However, legacy community computing systems do not support group need identification for ad hoc group formation, which would be one of key features of ubiquitous decision support systems and services. Hence, this paper aims to provide a multi-agent based methodology to enable nomadic community computing which supports ad hoc need identification and group formation. Focusing on supporting group decision-making of relatively small sized multiple individual in a community, the methodology copes with the following three characteristics: (1) ad hoc group formation, (2) context-aware group need identification, and (3) using mobile devices working in- and out-doors. NAMA-US, an RFID-based prototype system, has been developed to show the feasibility of the idea proposed in this paper.

• 대한수학교육학회지:학교수학
• /
• 제16권3호
• /
• pp.613-631
• /
• 2014

본 연구는 초등학교 5학년 수학영재 학생들의 소수와 합성수에 대한 개념형성의 과정을 활동이론의 틀로 분석한 것으로 계산기 환경의 소집단 활동체계가 개인이 개념 형성하는데 어떤 영향을 주는지 살펴보았다. 자료 분석은 학생 활동지, 관찰 기록, 동영상과 인터뷰의 녹취록을 활용하였다. Vygotsky, Tall & Vinner의 개념 형성 과정을 적용하여 학생들의 수학적 개념 형성의 수준을 파악하였고, 활동이론에 기초한 교실 전체 집단 활동체계와 소집단 활동체계를 분석하여 학생의 개념 형성 단계를 도식화하였다. 본 연구 결과에 따르면 서로 다른 소집단에 속하는 구성원은 소집단 활동을 하고 난 후 한 학생은 의사개념 단계로 발전하였지만 다른 한 학생은 복합적 사고 단계를 벗어나지 못하여 소집단의 활동체계의 활동요소간의 상호작용이 활동 주체인 각 학생의 수학적 개념 형성 과정에 영향을 주었다.

• 한국경영과학회:학술대회논문집
• /
• 대한산업공학회/한국경영과학회 1994년도 춘계공동학술대회논문집; 창원대학교; 08월 09일 Apr. 1994
• /
• pp.236-243
• /
• 1994

In this paper we consider the part-machine cell formation decision of the generalized Group Technology(GT) problem in which multiple process routes can be generated for each part. The existing p-median model and similarity coefficient algorithm can solve only small-sized or well-structured cases. We suggest an assignment method for the cell formation problem. This method uses an assignment model which is a simple linear programming. Numerical examples show that our assignment method provides good separable cells formation even for large-sized and ill-structured problems.

• 한국지구과학회지
• /
• 제23권1호
• /
• pp.30-37
• /
• 2002

Leptostrobus myeongamensis sp. nov. is newly described from the well-preserved but broken material occurring in the Upper Triassic Amisan Formation of the Nampo Group in Korea. This species is characterized by its lateral appendages of cone axis, each consisting of a rounded capsule and small scale leaf, and by its cone base covered with small scale leaves, the same size as in cone axis. This species is the first record from the Mesozoic strata in Korea.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제11권1호
• /
• pp.101-116
• /
• 1989

Proplast and Porous Polyethylene which have porous structures as low-modulus polymers have been recently used in maxillofacial plastic and reconstructive surgery. The purpose of this study was to compare the response of adajacent tissue, new bone formation and stability after augmentation by differen methods of subperiosteal graft using proplast and purous polythylene in rabbit mandible. The augmentation procedure was carried out by dividing into two groups, A and B. A group consisted of subperiosteal graft on the cortex, and the other B group was made up only graft following artificial decortication in the mandibular body of rabbit. The experimental animals were sacrificed on the 1st, 2nd, 4th and 8th week after grafting for macroscopic and light microscopic examination. The samples extracted at the 6th postgrafting week were also used for biometric testing and scanning electron microscopic examination. The results obtained from this study were as follows : 1. Macroscopically, infection of graft site, deformation and migration of graft material were not observed in all experimental groups. 2. B group showed more rapid and increased bone formation and the greater stability than A group, and tissue response was similar to each other. 3. In the tissue response, macrophages and cellular infiltrations were observed in Proplast group, but few in PHDPE group. 4. In bone formation of A group, Proplast group showed no bone formation until the 8th week, but PHDPE group showed small quantity of osteoid tissue from the 2nd week and appositional bone growth with new bone formation at the 8th week. 5. In bone formation of B group, both Proplast and PHDPE group showed bone formation, but PHDPE group showed more rapid and larger bone formation. 6. In pattern of bone formation, Proplast group mainly showed appositional bone growth pattern connected with graft site. On the other hand, PHDPE group showed mixed pattern of new bone formation in the pore connective tissue with appositional bone growth from graff site. 7. The maximum mean values of shear stress were serially $111.3gf/mm^{2}$ in PHDPE of B group, $84.8gf/mm^{2}$ in PHDPE of A group, $32.9gf/mm^{2}$ in Proplast B group, and $15.7gf/mm^{2}$ in Proplast of A group. From above results, It was suggested that the capacity of bone formation and stability between bone and graft material were dependent on the pore size and structure of graft material itself, the state of graft site and tissue response.

• BMB Reports
• /
• 제30권5호
• /
• pp.337-341
• /
• 1997

In order to investigate the role of a small GTP-binding protein RhoA in lysophosphatidic acid (LPA)-induced stress fiber formation, C3 ADP-ribosyltransferase was prepared by expressing in E. coli and then applied to Rat-2 fibroblasts. C3 transferase isolated from E. coli was as effective as the toxin from Clostridium botulinum in ADP-ribosylation of RhoA. Incubation of the cells with C3 transferase for 2 days induced ADP-ribosylation of RhoA by a dose-dependent manner, with a sub-maximal induction at $25\;{\mu}g/ml$. As expected, LPA-induced stress fiber formation was completely blocked by pre-incubation with C3 transferase for 2 days. However, exogenously added C3 transferase had no significant effect on the formation of phosphatidylethanol by LPA. These results suggested that phospholipase D was not activated by RhoA in the LPA-induced stress fiber formation.

• 지능정보연구
• /
• 제12권2호
• /
• pp.17-32
• /
• 2006

최근에 커뮤니티 컴퓨팅에서 그룹형성과 그룹 의사결정에 관한 이슈가 제기되고 있다. 그러나 기존의 커뮤니티 컴퓨팅 시스템에서는 그룹의 욕구를 인지함에 있어서 임시적인 방법으로 그룹을 형성하지 못하고 있다. 임시적인 방법의 그룹형성은 유비쿼터스 컴퓨팅의 의사결정지원 시스템과 서비스에서 중요한 특성 가운데 하나이다. 따라서 본 연구에서는 유목 커뮤니티 컴퓨팅에서 임시적으로 욕구를 인지하고 그룹을 형성할 수 있는 NAMA-US 에이전트 중심의 다중 에이전트 방법론을 제시하고자 한다. 이 방법론은 어떤 커뮤니티에서 상대적으로 작은 그룹의 복수의 개별 사용자의 그룹의사결정을 지원할 때 다음과 같은 세 가지 특성을 만족하고자 한다. 첫째 임시적인 그룹형성과, 둘째 상황인지 그룹 욕구인지, 그리고 셋째 실내. 외에서 동작 가능한 모바일 장비의 활용이다. RFID 기반의 프로토타입 시스템인 NAMA-US는 본 연구에서 제시하는 이런 개념을 실현시키기 위해 구축되었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제28권3호
• /
• pp.188-195
• /
• 2002

The purpose of this investigation was to evaluate the relationship between the hydration time of demineralized freeze-dried bone (DFDB) and early new bone formation in rat calvarial defects filled with DFDB. Rats (n = 43) were divided into 4 experimental groups. Standard, transosseous circular defects of the calvaria were made midparietally. In experimental group 1, the defect was grafted immediately after soaking the DFDB. In experimental group 2, the defects were grafted with DFDB after soaking the DFDB for 10 minutes. In experimental groups 3 and 4, the defects were filled after soaking the DFDB for 30 and 60 minutes, respectively. Graft sites were analyzed histologically after healing periods of 1, 2, or 4 weeks. Each group showed similar bone regeneration at each time point by histological analysis. The results of this study were as follows: 1. After 1 week, a significant amount of inflammation, granulation tissue, and edema were found. A small amount of bone was seen, but the amount of bone did not differ between groups. 2. After 2 weeks, a small amount of new bone formation and DFDB resorption were observed. 3. After 4 weeks, a greater amount of new bone formation was observed. The greatest amount of bone formation occurred in experimental group 4 after 4 weeks. We conclude that the hydration time of DFDB does not affect new bone formation and that it is very important to control inflammation in bone grafting.

• 천문학논총
• /
• 제30권2호
• /
• pp.517-519
• /
• 2015

A large-scale neutral hydrogen ($H\small{I}$) ring serendipitously found in the Leo I galaxy group is 200 kpc in diameter with $M_{H\small{I}}{\sim}1.67{\times}10^9M_{\odot}$, unique in size in the Local Universe. It is still under debate where this $H\small{I}$ ring originated - whether it has formed out of the gas remaining after the formation of a galaxy group (primordial origin) or been stripped during galaxy-galaxy interactions (tidal origin). We are investigating the optical and $H\small{I}$ gas properties of the dwarf galaxies located within the gas ring in order to probe its formation mechanism. In this work, we present the photometric properties of the dwarfs inside the ring using the CFHT MegaCam $u^{\ast}$, $g^{\prime}$, $r^{\prime}$ and $i^{\prime}$-band data. We discuss the origin of the gas ring based on the stellar age and metal abundance of dwarf galaxies contained within it.

• 한국초등과학교육학회지:초등과학교육
• /
• 제37권1호
• /
• pp.12-26
• /
• 2018

The purpose of this study was to investigate the characteristics of reasoning in which $3^{rd}$ grade elementary school students form ideas, design experiments, and interpret the results to solve problems in small group argumentation. For this purpose, 12 3rd-grade students' small group argumentations including experiments were observed. The researchers analyzed students' pre- and post-open questionnaires, field notes, and video recordings of small group argumentation. The results of the research are as follows. First, in the initial opinion formation process, a hasty unification of opinions and a transformation of inquiry problem occurred. In the design and execution of experiments, verification experiments and unplanned and arbitrary experiments were performed. They also selectively noticed or accepted claims, evidence, interpretation, and criticism. They could distinguish between the condition and the cause, but they were confused by using inaccurate terms and tended to keep the initial opinions when interpreting the results and drawing conclusions.