• Structural Engineering and Mechanics
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• 제37권6호
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• pp.617-632
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• 2011

A concept of crash energy absorbing (CEA) lattice structure for an inflatable morphing vehicle body (Lee et al. 2008) has been investigated as a method of providing rigidity and energy absorption capability during a vehicular collision (Lee et al. 2007). A modified analytical model for the CEA lattice structure design is described in this paper. The modification of the analytic model was made with a stiffness approach for the elastic region and updated plastic limit analysis with a pure plastic bending deformation concept and amended elongation factors for the plastic region. The proposed CEA structure is composed of a morphing lattice structure with movable thin-walled members for morphing purposes, members that will be locked in designated positions either before or during the crash. What will be described here is how to model the CEA structure analytically based on the energy absorbed by the CEA structure.

• Structural Engineering and Mechanics
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• 제56권3호
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• pp.409-422
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• 2015

In this paper, the Multi-Swarm Fruit Fly Optimization Algorithm (MFOA) is presented for structural damage identification using the first several natural frequencies and mode shapes. We assume damage only leads to the decrease of element stiffness. The differences on natural frequencies and mode shapes of damaged and intact state of a structure are used to establish the objective function, which transforms a damage identification problem into an optimization problem. The effectiveness and accuracy of MFOA are demonstrated by three different structures. Numerical results show that the MFOA has a better capacity for structural damage identification than the original Fruit Fly Optimization Algorithm (FOA) does.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2006년도 추계학술대회
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• pp.483-490
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• 2006

본 연구에서는 조직 구성원의 협업을 위하여 도입되는 그룹지원시스템(group support system; GSS)를 대상으로 GSS의 사용에 미치는 영향과 GSS의 사용으로 인한 개인의 성과의 관계에 대한 연구를 실시하였다. 본 연구를 위해 개인의 기술수용 요인에 대한 연구에서 보편적으로 널리 사용되어 온 기술수용모델(technology acceptance model; TAM)과 사용자의 과업과의 연관성을 고려한 과학기술적합(task-technology fit; TTF) 개념, 그리고 적응구조화이론(adaptive structuration theory; AST)을 통합하여 그룹 구성원들이 GSS의 도입의도에 맞게 사용하는 것이 개인과 조직의 성과를 향상시키는지 검증하였다. 연구결과, 높은 TTF는 사용자들이 GSS에 대하여 지각하는 유용성과 용이성에 영향을 미친다는 것을 검증하였다. 또한, TTF가 사용자들의 적절한 사용을 이끌고 있음을 검증하여 TTF 중심의 연구와 AST의 적절한 사용(faithfulness on appropriation; FOA)을 중심으로 하는 두 연구에 대한 통합 모델을 제시하였다.

• 한국실내디자인학회논문집
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• 제20권6호
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• pp.350-358
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• 2011

In contemporary architecture, Environment is not just a non-objective space. It is an experimental space where physical space and the principal result of interaction and order have been granted in symbolic, introverted space. Therefore, Yokohama International Port Terminal characteristics that appear in the architectural space, the nature of human desires and reveal the value of user-centered criteria to classify the type of response characteristics of the affordance are as follows; First, the experience response in the affordance reaction is when users reaction is multiple in theenvironment. Second, the evolution of organic reactions in a public space system is that it shows the spatial characteristics of the functional relationships. Third, the organic of space that can be seen through cultural practice in the inside and outside of the space could be explained as a perceptual response. It can be an opportunity to analyzed and develop in a various forms of space in environmental design if we understands the spatial characteristics of FOA's Yokohama International Port Terminal and applied end user spatial reaction analysis that shows an affordance relationship study.

• 정보처리학회논문지B
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• 제17B권1호
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• pp.55-62
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• 2010

인간의 시각 주의 시스템은 주어진 시각장면을 모두 다 처리하기보다는 주의가 집중되는 일정한 작은 영역들을 순간적으로 선택하여 그 부분만을 순차적으로 처리함으로써 복잡한 시각장면을 단순화시켜 쉽게 분석할 수 있는 능력을 가지고 있다. 본 논문에서는 주의 기반 시각정보 처리체계 시스템 구현을 위한 새로운 특징맵 구성 및 통합 방법을 제안한다. 제안하는 시스템에서는 시각특징으로서 색상, 명도, 방위, 형태 외에 2개의 스테레오 영상 쌍으로부터 얻을 수 있는 깊이 정보를 추가하여 사용하였다. 실험결과를 통해 깊이 정보를 사용함으로써 주의 영역의 정탐지율이 개선됨을 확인하였다.

• 한국실내디자인학회논문집
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• 제19권2호
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• pp.42-53
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• 2010

건축에 있어서 이론과 실제의 관계 문제는 오랫동안 건축 담론에 대한 주요 대상이 되어왔다. 이는 건축에서의 발전이 역사적으로 동시대의 사회적, 문화적, 경제적 환경의 진화와 더불어 진행되어 왔기 때문이며, 건축작업 선상에서 대두되는 이론과 실제의 관계와 맥락성이 건축의 주체성에 매우 중요한 요소로 여겨지기 때문이기도 하다. 1960년대부터 불거진 포스터모던주의의 사고적 영향은 건축분야의 의미와 가치에 있어서 학문과 실무분 야에서 새롭게 재조명되기 시작하였고, 기존 건축고유의 영역을 벗어나, 역사, 이론, 비평, 기술 및 디자인 분야로 확장되어 새롭고 다양한 접근 방법과 그 방식에 대한 고민을 추구하기 시작하였다. 건축작업에 중요한 근거를 제시해주는 비평적 사고를 유지하기 위하여, 이론적인 아이디어에서 실질적인 실무로서의 투사방법, 그리고 그 사이의 절충을 지속하기 위함은 특히 현대사회에서 더욱 복합적이며 다면적인 질문이 되고 있다. 이 논문은 건축의 투사 방법에 있어서 현대 건축가들이 자신들의 이론적인 관점과 그 관점을 건축적으로 가시화 시키는 관계성을 관찰하고, 어떻게 본인만의 논리와 프로세스를 추구하고 지속하는가에 대한 점을 연구하는데에 그 목적이 있다.

• 건축역사연구
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• 제27권5호
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• pp.17-26
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• 2018

In 1961, the Republic of Korea's first newly-constructed government building was completed. The government building, as ROK office, was erected as a twin with the USOM office in Sejong-ro. The reason why the ROK office and the USOM office were erected as a twin building is that the two offices were part of Foreign Operation Administration's Seoul Buildings Project in 1954. Within the project, the FOA office and the ROK office were rarely separated, and naturally, the ROK office was built according to the US standards. The planning, design, and construction phases which led by the US government were involved in the US architecture, engineering-construction companies. Because those AEC companies were familiar with the US technology and standards. In the phase of construction, Korean companies took part in the process under the supervise of Vinnell Corporation. The US expected to transfer its 'modern' and 'developed' technology through this process. The completed ROK office was widely known as the 'modern style (hyundae-sik)' building, which was body forth as glasses and new facilities. These factors were what the US emphasized for exporting architecture. The modifier, 'modern style (hyundae-sik)', given to the ROK office in the 1950s was a synonym for any new feeling that had never been seen hitherto. The newness of the ROK office, the 'modern style (hyundae-sik)' building, was specified as materials and facilities that indicates modern technology while in the absence of adequate knowledge.

• 한국위성정보통신학회논문지
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• 제10권4호
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• pp.146-150
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• 2015

COSPAS-SARSAT 위원회에서는 2000년 이후부터 새롭게 발사되는 미국, EU, 러시아의 중궤도 항법위성에 탐색구조 탑재체를 탑재하여 중궤도 탐색구조(MEOSAR) 서비스를 제공키로 결정하였다. 비컨에서 송출되는 조난신호는 비컨 상공의 각 위성들에 각기 다른 도달시간과 도플러 주파수를 가지고 도달하며, 이를 바로 중궤도 수신국(MEOLUT)으로 전달한다. 중궤도 수신국에서는 적어도 3~4개의 위성을 동시에 추적하여 조난신호를 전달받고, 조난신호 간 TDOA(Time Difference of Arrival)와 FDOA(Frequency Difference of Arrival)를 이용하여 비컨의 위치를 추정한다. 그러나 비컨은 임의의 시간에 50초 간격으로 조난신호를 송출하므로, 대형 조난상황에서 비컨 신호가 겹치는 현상이 나타날 수 있고, 겹쳐진 비컨 신호들을 COSPAS-SARSAT에서 개발하고 있는 현재 방식으로 모든 비컨 위치를 추정하는 것은 어렵다. 따라서 여기에서는 이를 해결하기 위한 방안으로 CAF MAP 알고리즘을 소개하고, COSPAS-SARSAT 시스템의 성능 요구사항을 만족시킬 수 있도록 MCAF MAP 기법을 제안하고, 그 성능을 나타낸다.

• 패션비즈니스
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• 제18권5호
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• pp.159-170
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• 2014

Recent concerns about the PFOA(perfluorooctanoic acid), have been increasing, which is generally applied in the water-repellent finishing process of textile products. It has been proven through animal testing to be harmful to humans, as possible carcinogens and neuro-toxic material. Thus U. S. Environmental Agency has gone as far as requiring the material to be eliminated in its entirety by 2015. As a viable alternative to this water-repellent finishing agent, the development of C6 product is gaining its popularity. The effects of PFOA finishing on the silk fabrics were examined, and we reviewed parameters of the needed process for optimizing appearance and functionality of silk fabrics treated with eco-friendly water-repellent finishing agent. Cross-linking agent affected the most on black color of reactive ink, among the physical properties. The contact angle reading was the highest in $8g/{\ell}$ of concentration for all fabrics. All the fabric specimens, subjected to the DTP and water repellent finishing, exhibited higher stiffness, where rayon specimen showed the highest, compared to the untreated specimens. The results may provide basic information leading to the development of value-added silk fabrics with water-repellency without excessive deterioration of the delicate appearance and inherent soft touch.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.252-261
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• 2006

Four experiments were conducted to investigate the effect of organic or inorganic acid supplementation on the growth performance, nutrient digestibility, intestinal measurements and white blood cell counts of weanling pigs. In growth trial (Exp I), a total of 100 crossbred pigs ({$Landrace{\times}Yorkshire$}${\times}$Duroc), weaned at $23{\pm}2$ days of age and $7.25{\pm}0.10kg$ average initial body weight (BW), were allotted to 5 treatments by body weight and sex in a randomized complete block (RCB) design. Three different organic acids (fumaric [FUA], formic [FOA] or lactic acid [LAA]) and one inorganic acid (hydrochloric acid [SHA]) were supplemented to each treatment diet. Each treatment had 5 replicates with 4 pigs per pen. During 0-3 wk, average daily gain (ADG), average daily feed intake (ADFI) and feed efficiency (G/F ratio) were not significantly different among treatments. However, pigs fed LAA or SHA diet showed improved ADG by 15 or 13% respectively and 12% greater ADFI in both treatments compared to CON diets. Moreover, compared to organic acid treatments, better ADG (p = 0.07) and ADFI (p = 0.09) were observed in SHA diet compared to pigs that were fed the diet containing organic acids (FUA, FOA or LAA). However, during 4-5 wk, no differences in ADG, ADFI and G/F ratio were observed among treatments. Overall, ADG, ADFI and G/F ratio were not affected by acidifier supplementation. Although it showed no significant difference, pigs fed LAA or SHA diets showed numerically higher ADG and ADFI than pigs fed other treatments. In metabolic trial (Exp II), 15 pigs were used to evaluate the effect of acidifier supplementation on nutrient digestibility. The digestibility of dry matter (DM), crude protein (CP), crude fat (CF), crude ash (CA), calcium (Ca) and phosphorus (P) was not improved by acidifier supplementation. Although the amount of fecal-N excretion was not different among treatments, that of urinary-N excretion was reduced in acidsupplemented treatments compared to CON group (p = 0.12). Subsequently, N retention was improved in acid-supplemented groups (p = 0.17). In anatomical trial (Exp III), the pH and $Cl^-$ concentrations of digesta in gastrointestinal (GI) tracts were not affected by acidifier supplementation. No detrimental effect of intestinal and lingual (taste bud) morphology was observed by acidifier supplementation particularly in inorganic acid treatment. In white blood cell assay (Exp IV), 45 pigs were used for measuring white blood cell (WBC) counts. In all pigs after LPS injection, WBC counts had slightly declined at 2 h and kept elevating at 8 h, then returned to baseline by 24 h after injection of lipopolysaccharide (LPS). However, overall WBC counts were not affected by acidifier supplementation. In conclusion, there was no difference between organic and inorganic acidifier supplementation in weanling pigs' diet, however inorganic acidifier might have a beneficial effect on growth performance and N utilization with lower supplementation levels. Furthermore, inorganic acidifier had no negative effect on intestinal measurements and white blood cell counts in weanling pigs. These results suggested that inorganic acidifier might be a good alternative to organic acidifiers in weanling pigs.