• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제5권4호
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• pp.449-456
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• 1999

본 논문은 C++에 분산 객체 프로그래밍 기능을 추가한 D++ 언어를 제안한다. 대등관계 복제객체 모델을 지원하는 D++는 분산 클래스의 정의, 멤버 함수의 일치성 제어 정의 기능, 그리고 영구 객체 이름에 기반한 분산 객체를 정의할 수 있는 언어 구조를 제공한다. D++ 프로그램에서 새로이 생성되는 분산 객체는 생성 시에 제공되는 객체의 영구 이름과 동일한 영구 이름을 갖는 분산 객체가 존재할 경우 해당 객체들과 복제 관계를 유지함으로써 정보를 공유한다. 각 복제 객체들은 서로 간에 대등한 관계를 가지며, 멤버 함수 정의 시에 기술되는 특성에 따라 일치성이 유지된다. 이 같은 D++의 분산 객체 모델은 실시간 그룹웨어의 기본 요구 사항인 분산 환경에서의 정보 공유 및 사건 공지 기능을 자연스럽게 해결해 주기 때문에 실시간 그룹웨어의 개발을 효율적으로 지원할 수 있을 것으로 기대한다. Abstract This paper proposes D++ programming language that is an extension of C++ for distributed object oriented programming. The D++, which supports peer-to-peer object model, provides new language constructs for the definition of distributed classes, the definition of the consistency control of the member function and the definition of distributed object variables with the persistent name. In D++, when the persistent name of a newly created distributed object is same as that of an existing distributed object, the new distributed object replicates object state of the existing distributed object and thus they share the object state. The replicas have peer relation and the consistency among them is maintained according to the characteristic described on the definition of designated member functions. It is expected that D++ language increases efficiency in development of real-time groupware because the distributed object model of D++ naturally supports the information sharing and event notification that are the basic functions required when building real-time groupware.

• Steel and Composite Structures
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• 제20권1호
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• pp.127-145
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• 2016

Composite column design is strongly influenced by the computation of the critical buckling load, which is very sensitive to the effective flexural stiffness (EI) of the column. Because of this, the behaviour of a composite column under lateral loading and its response to deflection is largely determined by the EI of the member. Thus, prediction models used for composite member design should accurately mirror this behaviour. However, EI varies due to several design parameters, and the implementation of high-strength materials, which are not considered by the current composite design codes of practice. The reliability of the design methods from six codes of practice (i.e., AS 5100, AS/NZS 2327, Eurocode 4, AISC 2010, ACI 318, and AIJ) for composite columns is studied in this paper. Also, the reliability of these codes of practice against a serviceability limit state criterion are estimated based on the combined use of the test-based statistical procedure proposed by Johnson and Huang (1997) and Monte Carlo simulations. The composite columns database includes 100 tests of circular concrete-filled tubes, rectangular concrete-filled tubes, and concrete-encased steel composite columns. A summary of the reliability analysis procedure and the evaluated reliability indices are provided. The reasons for the reliability analysis results are discussed to provide useful insight and supporting information for a possible revision of available codes of practice.

• Structural Engineering and Mechanics
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• 제84권3호
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• pp.311-321
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• 2022

In the buildings with long spans and high floors, such as logistics warehouses and semiconductor factories, it is difficult to install supporting posts under beams during construction. Therefore, the size of structural members becomes larger inevitably, resulting in a significant increase in construction costs. Accordingly, a prestressed hybrid wide flange (PHWF) beam with hollowed steel webs was developed, which can reduce construction costs by making multiple openings in the web of the steel member embedded in concrete. However, since multiple openings exist and prestress is introduced only into the bottom flange concrete, it is necessary to identify the shear resistance mechanism of the PHWF beam. This study presents experimental shear tests of PHWF beams with hollowed steel webs. Four PHWF beams with cast-in-place (CIP) concrete were fabricated, with key variables being the width and spacing of the steel webs embedded in the concrete and the presence of shear reinforcing bars, and web-shear tests were conducted. The shear behavior of the PHWF beam, including crack patterns, strain behavior of steel webs, and composite action between the prestressed bottom flange and CIP concrete, were measured and analyzed comprehensively. The test results showed that the steel web resists external shear forces through shear deformation when its width is sufficiently large, but as its width decreased, it exerted its shear contribution through normal deformation in a manner similar to that of shear reinforcing bars. In addition, it was found that stirrups placed on the cross section where the steel web does not exist contribute to improving the shear strength and deformation capacity of the member. Based on the shear behavior of the specimens, a straightforward calculation method was proposed to estimate the web-shear strength of PHWF beams with CIP concrete, and it provided a good estimation of the shear strength of PHWF beams, more accurate than the existing code equations.

• 정보처리학회논문지A
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• 제11A권3호
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• pp.217-226
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• 2004

이 문에서는 교실수업에서 이루어지는 여러 종류의 협동학습모형 중 Jigsaw협동학습 모형을 토대로 협동학습 지원 시스템을 설계, 구현하였다. Jigsaw도형은 학생들이 모둠집단과 전문가집단으로 나누어 전문가 집단에서 학습주제에 대한 전문가가 되어야만 모둠집단의 구성원들에게 설명하고 이해시킬 수 있는 구조를 가지고 있다. Jigsaw모형에 따라 모든 학생들에게 동등한 참여 기회를 부여하고, 책임감 있는 학습자간의 활발한 상호작용이 이루어질 수 있도록 웹 기반 협동학습 지원 시스템을 구성하였다. 웹 기반 시스템을 이용하여 각 모둠집단에서 간은 전문 과제를 맡은 학습자끼리 모여 협동학습을 하면서 그 과제에 대해서는 전문가 수준의 학습할 수 있도록 전문가 학습메뉴를 제공하고, 모둠집단 성원에게 각자 맡은 전문주제에 대하여 학습내용을 제시할 수 있도록 모둠집단 학습메뉴를 제공하여 사이버 공간을 통한 책임감 있고 능동적인 학습의 효과를 기대할 수 있다.

• 한국전산구조공학회논문집
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• 제26권5호
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• pp.351-358
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• 2013

본 논문에서는 Pothead를 지지하는데 사용하는 지그의 고유진동수를 일정 범위로 제한하여 Pothead와 공진을 일으키지 않도록 하는 지그의 최적 설계안을 제시한다. 쿤 터커(Kuhn-Thucker) 조건을 적용한 최적기준법(Optimality criteria method)을 사용하여 위상 최적화를 수행하였고, 이 과정에서 유한요소 크기기 최적 형상에 미치는 영향을 검토하였다. 또한 위상 최적화 결과를 바탕으로 실험 계획법(Design of experiments)과 반응 표면법(Response surface method)을 사용하여 형상 및 치수 최적화를 수행하여 비교용 지그에 비해 전체 질량이 30% 감소되는 결과를 얻었다. 마지막으로 최적화된 지그의 내진 해석을 수행한 Pothead의 응답은 Metal Handbook에서 제시된 내진 응답을 만족하고 있다.

• 정보처리학회논문지B
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• 제10B권1호
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• pp.119-126
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• 2003

본 논문에서는 다중 플랫폼을 지원하는 네트워크 게임 포털 사이트를 구성하기 위하여 Game Omphalos 혹은 단순히 Gamphalos라 명명한 시스템을 제안하였다. 일반적으로 게임 포털사이트는 단순하게 서로 다른 여러 게임을 모아서 각각 개별적으로 실행할 수 있도록 해준다. 그러나 Gamphalos 시스템은 여기에 연결된 다양한 게임들을 사용할 수 있을 뿐만 아니라 상호 연동될 수 있도록 여러 게임의 데이터를 통합하였다. 이를 위하여 Gamphalos 시스템은 통합 아이디 관리와 통합 게임 데이터 처리를 위한 통합 게임 콘트롤 센터(LGCC)와 각 게임의 서버역할을 담당하는 로컬 게임 콘트롤 센터(LGCC) 등 2가지 주요 부분으로 구성된다. Gamphalos System에 가입한 사용자는 서로 다른 게임을 수행하면서 생성되는 게임자료들이 한곳으로 통합, 누적되므로 더욱 많은 점수를 획득하며 이문에 보다 짧은 시간 동안에 캐릭터를 많이 성장시킬 수 있다.

• Earthquakes and Structures
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• 제15권6호
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• pp.583-593
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• 2018

Seismic performance is particularly important for life-line structures, especially for long-span transmission tower line system subjected to multi-component ground motions. However, the influence of multi-component seismic loads and the coupling effect between supporting towers and transmission lines are not taken into consideration in the current seismic design specifications. In this research, shake table tests are conducted to investigate the performance of long-span transmission tower-line system under multi-component seismic excitations. For reproducing the genuine structural responses, the reduced-scale experimental model of the prototype is designed and constructed based on the Buckingham's theorem. And three commonly used seismic records are selected as the input ground motions according to the site soil condition of supporting towers. In order to compare the experimental results, the dynamic responses of transmission tower-line system subjected to single-component and two-component ground motions are also studied using shake table tests. Furthermore, an empirical model is proposed to evaluate the acceleration and member stress responses of transmission tower-line system subjected to multi-component ground motions. The results demonstrate that the ground motions with multi-components can amplify the dynamic response of transmission tower-line system, and transmission lines have a significant influence on the structural response and should not be neglected in seismic analysis. The experimental results can provide a reference for the seismic design and analysis of long-span transmission tower-line system subjected to multi-component ground motions.

• 대한가정학회지
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• 제38권5호
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• pp.153-166
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• 2000

The purpose of this study was to determine the extent to which Swedish group home for elderly people with dementia coed be applied to the situation in Korea. One hundred and ninety six Korean subjects, responsible for supporting a member of their family afflicted with such an illness in their own homes, comprised the sample population for this study. Data was collected using questionnaires. frequency distribution, mean, and chi-square tests were used to analyze the data. The results of this study indicated a great possibility for adapting these kinds of group home in Korea. The respondents showed positive opinions with the basic concepts and space plans of Swedish group homes excepts for some details, like the number of residents per room. The respondents felt that a group home for dementia with the fellowing features was desirable : smart scale, single-family detached house,3-4 rooms, a total of 6-8 residents, managed by non-profit organizations or the government at a monthly cost of 530,000-1,000,000 won. In order to develope these group homes for dementia people in Korea, political assistance, combined with economic support, are strongly needed. The successful establishment of a group home will contribute not only to the welfare of elderly people with dementia but to their families as well.

• 융합보안논문지
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• 제3권1호
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• pp.31-37
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• 2003

무선통신 시스템의 표준으로 되어있는 TETRA(Trans-European Trunked RADIO) 시스템의 그룹 서비스와 소그룹 서비스의 안전한 통신을 위한 모델을 제안한다. 먼저, TETRA 시스템의 통신 서비스를 위해 인가된 구성원만이 데이터를 수신할 수 있어야하므로 안전한 브로드캐스팅 기술이 필요하다. 따라서, 본 논문에서 제안한 모델을 적용하면 소그룹 내부적으로 안전한 TETRA 통신 서비스를 위해 소그룹 키를 공유하고 그룹 내에서 이루어지는 TETRA 그룹통신 서비스를 위해 인가된 모든 구성원들이 안전하게 그룹 키를 공유하게 된다. 또한, TETRA 시스템의 통신서비스에서 그룹통신을 행함과 동시에 소그룹통신이 가능하게 된다.

• ALGAE
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• 제25권3호
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• pp.105-113
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• 2010

A new red algal parasite, Symphyocolax koreana M. S. Kim, gen. et sp. nov., has been found on a specimen of Symphyocladia latiuscula (Harvey) Yamada, a member of the tribe Pterosiphonieae of the Rhodomelaceae; this genus has never before been reported to host red algal parasites. Here, the new parasite from Korea is described in terms of vegetative and reproductive morphology. The thallus has a minute, colored polysiphonous upright axis with many branches attached by pseudoparenchymatous pulvinate bases. There are six pericentral cells, with many corticated cells in the lower part of the main branches. Trichoblasts occur on dioecious male and female gametophytes, but not on tetrasporophytes. Procarps develop on suprabasal cells of trichoblasts and consist of a four-celled carpogonial branch and two sterile cells attached to the supporting cell. Spermatangial branches are borne one per each successive segment on monosiphonous pedicels in spiral positions with fertile trichoblast. Tetrasporangia are formed one per segment in a straight series and are tetrahedrally divided. Features of the vegetative axes, procarp, spermatangial trichoblasts, and tetrasporangial branching show that the new genus is an alloparasite belonging to the tribe Polysiphonieae.