• 접착 및 계면
• /
• 제9권3호
• /
• pp.20-26
• /
• 2008

형상기억합금(SMA)의 구조는 부가된 온도 혹은 응력에 의해 마텐자이트로부터 오스테나이트로의 변화가 가능하다는 것은 잘 알려져 있다. 형상기억합금섬유의 자체 형상회복력으로 인해 응력과 온도가 적용되는 동안에 응력이나 경화 모니터링 센서 또는 작동기로서 사용되었다. 초탄성 현상은 연속적인 기계적 하중 하에서나 온도변화 중에 응력-변형률 곡선에서 확인되었다. 반복하중 실험을 통해 응력-변형률 곡선에서 나타난 초탄성 현상 구간이 나타나는 응력 이력현상이 발생함을 확인하였다. 이것은 형상기억합금섬유 혹은 에폭시에 함침된 형상기억합금섬유 복합재료가 반복하중으로 계면물성 저하로 인한 형상기억 회복 성능의 저하를 의미한다. 강성도가 큰 에폭시 사용과 형상기억합금섬유의 표면처리 이후 형상기억합금섬유와 에폭시 사이의 계면결합력의 증대에도 불구하고 유사한 불완전한 초탄성을 보여 주었다. 단-형상기억합금섬유/에폭시 복합재료 내부에 남은 잔류 열과 이에 따른 잔류 응력으로 인해 에폭시에 함침된 단-형상기억합금섬유에서는 경화과정에서 불완전한 회복을 나타났다.

• 안보군사학연구
• /
• 통권5호
• /
• pp.241-280
• /
• 2007

This study examines the relationship of the industry-specific factors that effect innovation of manufacturing technology and the market share within the defense industry. Since the establishment of the basic defense industry framework in 1973, there were numerous interactions of the industry-specific factors of the defense industry structure with the technological innovation and market organization of the defense industry. During last three decades, the domestic defense industry has achieved the considerable level but the framework of the basic system has not developed much in areas of the military science and the defense manufacturing technology. Industry-specific factors were formed in the process and appeared in a variety of behavioral characteristics as subsystems. Currently, there IS a growing trend where the management of defense industry is gradually deteriorating due to limitation of the domestic industry-specific factor (e.g. defense technologies, amount of demand, etc.). If there is a prominent imbalance of the industry-specific factors. it can trigger the potential problem of conflict, lack of cooperation and control, slowing the growth of the manufacturing technology thereby diminishing the market and deteriorating the defense supply/demand relationship. In a research conducted by Joe S. Bain, Bain analyzed the relationship of the traditional industrial organization where industry-specific factor(S) not only impacts the conductor(C). And, conductor(C) influences the shaping of the performance(P) of relationship of the traditional industrial organization. Consequently, the researcher has identified the demand monopoly, barriers to entry, and market competition with comparison of defense industry issues. These defense issues were three industry-specific factors identified, which are 1) The demand monopoly and The entry barriers to new market competition, 2) the industrial technical factor to a production technical competitiveness and a market sharing competitiveness, 3) the probability factor to revolution for military affairs(RMA) and a R&D production. According to baseline with these factors, the following research model is established from the special companies group(Group A), the systematization companies group(Group B), and the general companies group(Group 0. The hypothesis is that if there are more industry-specific factors, then there will be more relationships of defense industry relation statutes. This research is an empirical study on the relationship that the industry specific factors effects the innovation of manufacturing technology and the shaping of the market in the defense industry. Moreover, the existing models to evaluate the industry specific factors of the defense industry IS much to be desired with the controlled statistical analysis of the result. It is vital to study on current situation with suggesting alternative strategy to the efficient strategy. The descriptive analysis approach analysis is conducted with SPSSWIN to conduct reliability test, factor analysis, correlation analysis, cross-tabulation analysis, one-way ANOVA, and multiple regression analysis. However, there were some limitations of the survey such as the rigidity of concept about the technical factors and various market management factors. The wishes is that the decision-maker could be utilized these defence industrial factors to formulate efficient defence policy and strategy in the future.

• 디지털융복합연구
• /
• 제14권12호
• /
• pp.323-333
• /
• 2016

본 연구는 일부 여대생의 자아존중감, 무망감, 우울, 통제위치 및 A형행동유형과 취업스트레스간의 관련성을 파악하고 취업스트레스에 미치는 융복합적 영향을 분석하였다. 조사대상은 전북지역에서 임의로 선정된 531명의 여대생으로 하였으며, 자료수집은 2016년 3월 28일부터 4월 29일까지 자기기입식 설문지를 통해 이루어졌다. 위계적다중회귀분석 결과, 자아존중감이 낮을수록, 무망감이 높을수록, 우울이 높을수록, 외적통제위치가 높을수록, A형행동 유행이 높을수록 취업스트레스가 높았으며 이들의 설명력은 43.2%이었다. 공분산 구조분석 결과, 자아존중감, 무망감, 우울, 통제위치 및 A형 행동유형과 취업스트레스의 인과관계가 확인되었다. 이상의 연구결과를 볼 때, 여대생의 취업스트레스를 낮추기 위해서는 자아존중감을 높이고 무망감, 우울, 통제위치 및 A형행동유형을 낮추는 노력이 필요하다. 이러한 결과는 여대생의 취업스트레스를 줄이는 프로그램 및 정책 개발에 활용이 기대된다. 향후연구에서는 취업스트레스에 영향을 미치는 추가요인에 대한 분석이 필요하다.

• Journal of Periodontal and Implant Science
• /
• 제36권2호
• /
• pp.531-554
• /
• 2006

Oral implants must fulfill certain criteria arising from special demands of function, which include biocompatibility, adequate mechanical strength, optimum soft and hard tissue integration, and transmission of functional forces to bone within physiological limits. And one of the critical elements influencing the long-term uncompromise functioning of oral implants is load distribution at the implant- bone interface, Factors that affect the load transfer at the bone-implant interface include the type of loading, material properties of the implant and prosthesis, implant geometry, surface structure, quality and quantity of the surrounding bone, and nature of the bone-implant interface. To understand the biomechanical behavior of dental implants, validation of stress and strain measurements is required. The finite element analysis (FEA) has been applied to the dental implant field to predict stress distribution patterns in the implant-bone interface by comparison of various implant designs. This method offers the advantage of solving complex structural problems by dividing them into smaller and simpler interrelated sections by using mathematical techniques. The purpose of this study was to evaluate the stresses induced around the implants in bone using FEA, A 3D FEA computer software (SOLIDWORKS 2004, DASSO SYSTEM, France) was used for the analysis of clinical simulations. Two types (external and internal) of implants of 4.1 mm diameter, 12.0 mm length were buried in 4 types of bone modeled. Vertical and oblique forces of lOON were applied on the center of the abutment, and the values of von Mises equivalent stress at the implant-bone interface were computed. The results showed that von Mises stresses at the marginal. bone were higher under oblique load than under vertical load, and the stresses were higher at the lingual marginal bone than at the buccal marginal bone under oblique load. Under vertical and oblique load, the stress in type I, II, III bone was found to be the highest at the marginal bone and the lowest at the bone around apical portions of implant. Higher stresses occurred at the top of the crestal region and lower stresses occurred near the tip of the implant with greater thickness of the cortical shell while high stresses surrounded the fixture apex for type N. The stresses in the crestal region were higher in Model 2 than in Model 1, the stresses near the tip of the implant were higher in Model 1 than Model 2, and Model 2 showed more effective stress distribution than Model.

• Restorative Dentistry and Endodontics
• /
• 제20권2호
• /
• pp.432-461
• /
• 1995

The basic principles in the design of Class II amalgam cavity preparations have been modified but not changed in essence over the last 90 years. The early essential principle was "extension for prevention". Most of the modifications have served to reduce the extent of preparation and, thus, increase the conservation of sound tooth structure. A more recent concept relating to conservative Class II cavity preparations involves elimination of occlusal preparation if no carious lesion exists in this area. To evaluate the ideal ClassII cavity preparation design, if carious lesion exists only in the interproximal area, three cavity design conditions were studied: Rodda's conventional cavity, simple proximal box cavity and proximal box cavity with retention grooves. In this study, MO amalgam cavity was prepared on maxillary first premolar. Three dimensional finite element models were made by serial photographic method. Linear, eight and six-nodal, isoparametric brick elements were used for the three dimensional finite element model. The periodontal ligament and alveolar bone surrounding the tooth were excluded in these models. Three types model(B option, Gap option and R option model) were developed. B option model was assumed perfect bonding between the restoration and cavty wall. Gap option model(Gap distance: $2{\mu}m$) was assumed the possibility of play at the interface simulated the lack of real bonding between the amalgam and cavity wall (enamel and dentin). R option model was assumed non-connection between the restoration and cavty wall. A load of 500N was applied vertically at the first node from the lingual slope of the buccal cusp tip. This study analysed the displacement, 1 and 2 direction normal stress and strain with FEM software ABAQUS Version 5.2 and hardware IRIS 4D/310 VGX Work-station. The results were as followed. 1. Rodda's cavity form model showed greater amount of displacement with other two models. 2. The stress and strain were increased on the distal marginal ridge and buccopulpal line angle in Rodda's cavity form model. 3. The stress and strain were increased on the central groove and a part of distal marginal ridge in simple proximal box model and proximal box model with retention grooves. 4. With Gap option, Rodda's cavity form model showed the greatest amount of the stress on distal marginal ridge followed by proximal box model with retention grooves and simple proximal box model in descending order. 5. With Gap option, simple proximal box model showed greater amount of stress on the central groove with proximal box model with retention grooves. 6. Retention grooves in the proximal box played the role of supporting the restorations opposing to loads.

• 만화애니메이션 연구
• /
• 통권25호
• /
• pp.177-201
• /
• 2011

한국애니메이션영화제 역사는 1997년 서울 국제만화애니메이션페스티벌(SICAF), 1999년 부천 국제학생애니메이션페스티벌(PISAF)이 10년을 넘어서 대표적인 애니메이션영화제로 현재까지 지속해 오고 있다. 그럼에도 초기의 성과와 비교한다면 관객의 애니메이션영화제에 대한 참여와 관심은 줄어들고 있으며, 애니메이션 산업중흥 및 애니메이션 장르의 확장이라는 목표는 최근 애니메이션산업의 위기와 맞물려 애니메이션 영화제 또한 위축되어온 것이 사실이다. 본 연구의 목적은 4대 국제애니메이션영화제로 불리는 안시 국제애니메이션영화제, 자그레브 국제애니메이션영화제, 오타와 국제애니메이션영화제, 히로시마 국제애니메이션영화의 특징과 최근 경향을 살펴보면서 한국애니메이션영화제 발전방향에 관하여 모색한다. 21세기 들어서 애니메이션은 그 장르의 경계가 모호해진 가운데, 기술적인 진보와, 3D, CG로 대표되는 제작환경의 변화 등으로 급격한 패러다임의 전환기를 맞이하고 있다. 4대 국제애니메이션영화제는 이를 적극적으로 수용하거나 혹은 선별적인 도입을 통하여 각자의 문화정체성과 애니메이션 제작 및 산업 활성화를 유도하는 방향으로 전개해 나갔다. 특히 이런 변화에 맞추어 세계의 애니메이션영화제 비교분석을 통하여 한국의 애니메이션영화제의 발전방향을 모색하는 것은 지금에 있어 시의 적절하면서도 의미 있는 작업이다. 이 논문에는 그동안 안시영화제 방문경험과 안시에서 만난 다양한 국제영화제 인적교류를 통해 얻은 정보들을 기반으로 각각의 해외애니메이션영화제 특성과 그 운영을 비교분석함으로서 한국애니메이션영화제가 애니메이션 미래의 비전을 주도적으로 창조할 수 있도록 발전방향을 제시하고자 한다. 이들 4대 영화제들의 성공기반은 오랜 전통과 역사에서 비롯된 안정적인 시스템- 전용상영관, 관객의 적극적 참여, 지속적인 정체성확립과 특성화, 상호간 국제네트워크협력에 있다. 따라서 이들 영화제에서 공통적으로 갖고 있는 기반을 구성하는 것이 한국애니메이션영화제에서 필수적인 조건이며, 여기에는 애니메이션의 자체 매력을 즐길 수 있는 애니메이션 교육목표와 과정이 수반되어야 할 것이다.

• 한국축산시설환경학회지
• /
• 제18권sup호
• /
• pp.29-34
• /
• 2012

본 연구는 돈사 슬러리 피트와 유사한 형태의 모형의 아크릴 반응조에서 분뇨를 6주간 배양하면서 2주 간격으로 악취물질의 농도를 측정하기 위해 수행되었다. 1. 분뇨를 6주간 저장하는 동안 2주 간격으로 단쇄지방산의 농도를 측정하였을 때 시간이 경과함에 따라 뚜렷하게 감소하였으며(p<0.05), 이성체지방산의 농도는 저장 4주 이후 크게 감소되었다(p<0.05). 2. 분뇨 저장기간별 페놀류 농도는 0, 2, 4, 6주에 각각 68.27, 47.69, 26.08, 8.84 ppm으로 시간 경과와 함께 크게 감소되었다(p<0.05). 3. 그러나 분뇨를 6주간 저장하는 동안 인돌류 농도는 저장 4주부터 증가되었다(p<0.05).

• 문화기술의 융합
• /
• 제7권2호
• /
• pp.419-425
• /
• 2021

이 연구는 패스파인더 시뮬레이션 프로그램을 활용하여 고속도로 휴게소에서 화재 시 피난 통로의 개수와 방향에 따른 피난안전성을 분석하였다. 또한, 시설물의 출입구를 2중 문으로 설치했을 경우와 단일 문으로 설치했을 경우를 비교하여 RSET 차이를 분석하였다. 1개의 출입구만을 개방했을 경우는 피난가능시간을 모두 초과하였다. 피난대책의 일반적인 원칙인 두 방향 이상의 피난 통로를 확보하기 위해 2개 이상의 출입구를 개방하였을 경우는 피난가능시간 안에 모두 대피하는 결과를 얻었다. 두 방향 이상의 출입구를 개방할 경우에는 서로 동일방향이 아니어야 RSET가 짧아진다는 것을 알 수 있었다. 2중 문 보다는 단일 문으로 출입문을 설치했을 경우 RSET이 단축된다는 결과를 얻었다. 또한 이 연구를 통하여 고속도로 휴게소의 RSET를 단축시키기 위해 첫째, 두 방향 이상의 피난 통로를 상시 확보할 필요가 있으며, 둘째, 두 방향 이상의 피난 통로는 동일한 방향이 되지 않아야 한다는 것과 마지막으로, 2중 문보다는 단일 문으로 출입구를 설치해야 함을 제안하였다.

• Journal of Korean Neurosurgical Society
• /
• 제65권2호
• /
• pp.204-214
• /
• 2022

Objective : Osteoporosis result from age-related decline in the number of osteoblast progenitors in the bone marrow. Probiotics have beneficial effects on the host, when administered in appropriate amounts. This study investigated the effects of probiotics expressing specific genes, especially the effects of genetically modified bone morphogenetic protein (BMP)-2-expressing Lactobacillus plantarum CJNU 3003 (LP) on ovariectomized rats. Methods : Twenty-eight female Wistar rats (250-300 g, 12 weeks old) were divided into four groups : the sham (control), the ovariectomy (OVX)-induced osteoporosis group (OVX), the OVX and LP (OVX/LP), OVX and genetically modified BMP-2-expressing LP (OVX/LP with BMP) groups. The three groups underwent bilateral OVX and two of these groups were administered two different types of LP via oral gavage daily. At 16 weeks post-OVX, blood was collected from the heart and the bilateral tibiae were extracted and were scanned by ex-vivo micro-computed tomography and stained with hematoxylin-and-eosin (H&E) and Masson's trichrome stain for pathological assessment. The serum levels of osteocalcin (OC), rat C-telopeptide of type I collagen (CTX-I), BMP-2, and receptor activator of nuclear factor-ĸB ligand (RANKL) were measured. Results : The 3D-micro-computed tomography images showed that the trabecular structure in the OVX/LP with BMP group was maintained compared with OVX and OVX/LP groups. No significant differences were detected in trabecular thickness (Tb.Th) between control and OVX/LP with BMP groups (p>0.05). Furthermore, a tendency toward increased BMD, trabecular bone volume, Tb.Th, and trabecular number and decreased trabecular separation was found in rats in the OVX/LP with BMP groups when compared with the OVX and OVX/LP groups (p>0.05). The H&E and Masson's trichrome stained sections showed a thicker trabecular bone in the OVX/LP with BMP group compared with the OVX and OVX/LP groups. There was no difference in serum levels of OC, CTX and RANKL control and OVX/LP with BMP groups (p>0.05). In contrast, significant differences were found in OC and CTX-1 levels between the OVX and OVX/LP with BMP groups (p<0.05). Conclusion : Our results showed that the expression of genetically modified BMP-2 showed inhibition effect for bone loss in a rat model of osteoporosis.

• 국제학술발표논문집
• /
• The 9th International Conference on Construction Engineering and Project Management
• /
• pp.1249-1249
• /
• 2022

The facade, an exterior material of a building, is one of the crucial factors that determine its morphological identity and its functional levels, such as energy performance, earthquake and fire resistance. However, regardless of the type of exterior materials, huge property and human casualties are continuing due to frequent exterior materials dropout accidents. The quality of the building envelope depends on the detailed design and is closely related to the back frames that support the exterior material. Detailed design means the creation of a shop drawing, which is the stage of developing the basic design to a level where construction is possible by specifying the exact necessary details. However, due to chronic problems in the construction industry, such as reducing working hours and the lack of design personnel, detailed design is not being appropriately implemented. Considering these characteristics, it is necessary to develop the detailed design process of exterior materials and works based on the domain-expert knowledge of the construction industry using artificial intelligence (AI). Therefore, this study aims to establish a detailed design automation algorithm for AI-based condition-responsive exterior wall panels and their back frames. The scope of the study is limited to "detailed design" performed based on the working drawings during the exterior work process and "stone panels" among exterior materials. First, working-level data on stone works is collected to analyze the existing detailed design process. After that, design parameters are derived by analyzing factors that affect the design of the building's exterior wall and back frames, such as structure, floor height, wind load, lift limit, and transportation elements. The relational expression between the derived parameters is derived, and it is algorithmized to implement a rule-based AI design. These algorithms can be applied to detailed designs based on 3D BIM to automatically calculate quantity and unit price. The next goal is to derive the iterative elements that occur in the process and implement a robotic process automation (RPA)-based system to link the entire "Detailed design-Quality calculation-Order process." This study is significant because it expands the design automation research, which has been rather limited to basic and implemented design, to the detailed design area at the beginning of the construction execution and increases the productivity by using AI. In addition, it can help fundamentally improve the working environment of the construction industry through the development of direct and applicable technologies to practice.