• Steel and Composite Structures
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• 제29권1호
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• pp.1-22
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• 2018

Multi-storey precast concrete skeletal structures are assembled from individual prefabricated components which are erected on-site using various types of connections. In the current design of these structures, beam-to-column connections are assumed to be pin jointed. Welded plate beam to-column connections have been used in the precast concrete industry for many years. They have many advantages over other jointing methods in component production, quality control, transportation and assembly. However, there is at present limited information concerning their detailed structural behaviour under bending and shear loadings. The experimental work has involved the determination of moment-rotation relationships for semi-rigid precast concrete connections in full scale connection tests. The study reported in this paper was undertaken to clarify the behaviour of such connections under symmetrical vertical loadings. A series of full-scale tests was performed on sample column for which the column geometry and weld arrangements conformed with successful commercial practice. Proprietary hollow core slabs were tied to the beams by tensile reinforcing bars, which also provide the in-plane continuity across the connections. The strength of the connections in the double sided tests was at least 0.84 times the predicted moment of resistance of the composite beam and slab. The secant stiffness of the connections ranged from 0.7 to 3.9 times the flexural stiffness of the attached beam. When the connections were tested without the floor slabs and tie steel, the reduced strength and stiffness were approximately a third and half respectively. This remarkable contribution of the floor strength and stiffness to the flexural capacity of the joint is currently neglected in the design process for precast concrete frames. In general, the double sided connections were found to be more suited to a semi-rigid design approach than the single sided ones. The behaviour of double sided welded plate connection test results are presented in this paper. The behaviour of single sided welded plate connection test results is the subject of another paper.

• 한국산학기술학회논문지
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• 제16권3호
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• pp.2172-2177
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• 2015

상수 모듈러스 오차의 확률을 영으로 줄이는 등화 알고리듬에 결정 궤환 방식이 도입된 DF-MZEP-CME (decision feedback - maximum zero-error probability for constant modulus errors) 알고리듬은 채널 왜곡 보상에서 보다 향상된 성능을 보인다. 그러나 이 DF-MZEP-CME 알고리듬은 기울기 계산에서 샘플 사이즈에 비례하는 계산량을 가지게 되어 구현상 장애요인으로 작용한다. 이 논문에서는 DF-MZEP-CME 알고리듬의 기울기를 반복적으로 추정하도록 하여 계산량이 샘플 사이즈와 무관하게 함으로서 계산량 문제를 해결한다. 샘플 사이즈 N 에 대해 기존 알고리듬이 10N 의 곱셈량을 가지지만 제안한 방식은 샘플 사이즈와 무관하게 단지 20 번의 곱셈을 수행한다. 또한 제안한 방식의 기울기 계산이 초기상태로부터 안정 상태로 넘어갈 때 연속성을 유지하는 것으로 나타나 오차 전파에 예민한 결정 궤환 방식에 매우 적합한 알고리듬으로 판단된다.

• 한국조경학회지
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• 제32권6호
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• pp.68-81
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• 2005

The styles of contemporary landscape design have diversified since the emergence of Postmodernism in landscape architecture. The diversification was mostly influenced by contemporary fine arts and architecture. This study examines the pluralistic development of Postmodern landscape design through the investigation of the influences from those sister arts. In this point of view, the main approaches of Postmodern landscape design are thought to be classified into three categories;'the formal abstract approach', 'the figurative approach' and 'the new picturesque approach'. The first category of the formal abstract approach was formulated with the concepts and vocabulary of Minimal Art and Installation Art. Its representative icons such as 'point grids' and 'stripes', and the main concepts such as the sense of 'flahess', 'expansion' and 'materiality' are mostly thought to be originated from these art forms. The second category of the figurative approach is characterised by the concepts and vocabulary of Pop Art and New Image Paintings. Its representative icons such as 'map' or 'figurative forms' and main concepts like the sense of 'reality', 'context' and 'symbolism' are mostly thought to be originated from these art forms. The third category of the new picturesque approach was formulated with the concepts and vocabulary of Land Art and Late Deconstructive Architecture. Its representative icons such as 'hybrid', 'layer' and 'fold', and the main concepts such as the sense of 'complexity', 'continuity' and 'reversibility' are thought to be originated from these art forms. The research shows that the main stream of contemporary landscape design seems to be gradually moving toward the second and third approach above, in step with the cultural orientation and the dynamism of contemporary urban life. Therefore, the study focused especially on the new picturesque approach which would be in greater need for coping with the hybrid culture today.

• 대한한의학원전학회지
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• 제33권4호
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• pp.1-19
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• 2020

Objectives : This paper aims to understand the meaning and utilitarian values of 'Jongyong(從容)' in medicine by studying its meaning in the 『Huangdineijing』. Methods : Examples of 'Jongyong(從容)' usages in Chinese literature and classical texts were studied first. Next, the similarities and characteristics of its contexts in discourses between Leigong and Huangdi were examined, followed by further examination of the overall meanings of the six chapters, 「Shicongronglunpian(示從容論篇)」, 「Zhuzhijiaolunpian(著至敎論篇)」, 「Shuwuguolunpian(疏五過論篇)」, 「Zhengsishilunpian(徵四失論篇)」, 「Yinyangleilunpian(陰陽類論篇)」, 「Jiejingweilunpian(解精微論篇)」 and the verses that include 'Jongyong(從容).' Results : Generally 'Jongyong(從容)' describes a resilient attitude that responds appropriately and calmly to difficult external situations while maintaining one's character, or refers to one's general behavior. In the 『Huangdineijing』, 'Jongyong(從容)' is only mentioned in discourses between Leigong and Huangdi, which talks about ancient East Asian clinical medicine in general, its transmission and education. Here, the meaning of 'Jongyong(從容)' could be summarized as an expansion of analogical thinking[引比類], medical work that involves the physician's commitment(人事), and detailed measurement of yinyang difference in the body(刑法, 陰陽, 治數). Discussion : In ancient East Asian medicine, the meaning of 'Jongyong(從容)' is closer to measurement of the yinyang difference rather than differentiation of the five element analogy. It is a medical practice that measures the shape, volume, length, area, height, concentration etc. of the human body in numerical figures to allow for the most subtle comparison, which was an important aspect of the physician's work that needed to be demonstrated, educated and transmitted to later generations to enable continuity of the medical profession.

• 중소기업융합학회논문지
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• 제6권2호
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• pp.11-17
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• 2016

최근 IT 기술이 발달함에 따라 기업에서 생성되는 다양한 종류의 데이터(또는 정보)가 외부의 기관이나 개인에게 유출되는 상황이 잦아지고 있다. 그러나 기업 차원에서 기업 정보의 역기능을 줄이기 위한 대응방인이 미흡한 상황이다. 본 논문에서는 기업 정보화의 역기능을 최소화하기 위한 역할기반의 기업 정보 처리 모델을 제안한다. 제안 모델은 기업 정보를 관리 및 감독하기 위한 관련 부서를 통해 기업 정보를 보호하고, 신속하고 체계적인 복구 및 운영 전략을 수립할 수 있도록 하여 기업 정보화 서비스의 효율성을 향상시켰다. 제안 모델은 정보에 접근하는 사용자의 권한과 역할을 관리자가 중앙 관리하여 정보에 접근하는 사용자가 이상 징후가 포착되면 정보 접근을 차단한 후 신속하고 체계적인 복구 및 운영 연속성 전략을 수립하고 있다. 실험 결과, 제안 모델은 기존 모델에 비해 바이러스 피해가 48.8% 낮았다. 또한, 기업내 발생되는 정보 역기능에 대한 유통 건수는 기존 모델에 비해 17.9% 낮은 결과를 얻었다.

• 대한조선학회지
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• 제22권3호
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• pp.9-18
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• 1985

The numerical calculation for solving boundary-value problem related to potential flows with a free surface is carried out by application of the localized finite element method. Only forced motion of 2-D body in infinitely deep fluid is considered, although this schemes is equally applicable to any first order time-harmonic problems of similar nature. The infinite domain of the fluid is separated into the inner flow field and the outer flow field with common inter-surface boundary. The finite element method is applied to obtain the solution in the inner flow field and the Green functions are utilized to represent the solution in the outer flow field. At the inter-surface boundary, the continuity of the value of potential and the normal derivative of the potential(i.e. matching condition) is conserved. The present method has better computational efficiency than the previous LFEM and the integral equation method of Frank. This enhanced computational efficiency is presumably due to the fact that the present method gives a symmetric coefficient matrix and requires less computational time in calculating the influence coefficient matrix of Green function than the integral equation method. And the irregular frequency desen't exist because the uniqueness of the solution is assured by the such that the exact free surface condition is satisfied on the boundary of the localized finite element region(i.e. inner region). As an example of the above method, the hydrodynamic forces for the circular cylinder and the rectangular cylinders are calculated. In the computed results, the small number of singularity distribution segments($3{\sim}6$) give good result relative to Ursell's and Vugts'.

• Safety and Health at Work
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• 제11권3호
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• pp.275-283
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• 2020

Background: In the absence of a vaccine or treatment, the most pragmatic strategies against an infectious disease pandemic are extensive early detection testing and social distancing. This study aimed to summarize public and workplace responses to Coronavirus Disease-19 (COVID-19) and show how the Korean system has operated during the COVID-19 pandemic. Method: Daily briefings from the Korean Center for Disease Control and the Central Disaster Management Headquarters were assembled from January 20 to May 15, 2020. Results: By May 15, 2020, 11,018 COVID-19 cases were identified, of which 15.7% occurred in workplaces such as health-care facilities, call centers, sports clubs, coin karaoke, and nightlife destinations. When the first confirmed case was diagnosed, the Korean Center for Disease Control and Central Disaster Management Headquarters responded quickly, emphasizing early detection with numerous tests and a social distancing policy. This slowed the spread of infection without intensive containment, shut down, or mitigation interventions. After entering the public health blue alert level, a business continuity plan was distributed. After entering the orange level, the Ministry of Employment and Labor developed workplace guidelines for COVID-19 consisting of social distancing, flexible working schedules, early identification of workers with suspected infections, and disinfection of workplaces. Owing to the intensive workplace social distancing policy, workplaces remained safe with only small sporadic group infections. Conclusion: The workplace social distancing policy with timely implementation of specific guidelines was a key to preventing a large outbreak of COVID-19 in Korean workplaces. However, sporadic incidents of COVID-19 are still ongoing, and risk assessment in vulnerable workplaces should be continued.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권4호
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• pp.353-360
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• 2009

양측 구순열의 코-입술 동시 수술의 원칙이 확립되었고 기법은 계속 진화하고 있다. 이에 따라 예전에 전형적으로 보이던 양측 구순열비의 오점들이 더 이상 명확히 보이지 않게 되고 있다. 외과의사들은 양측 구순열비 교정에 대한 원칙을 숙지하고 술전 악정형치료를 효과적으로 유도하고 성장이라는 4차원적 변화를 예견하는 3차원적 설계와 코-입술 동시 수술의 기법을 채득하여 환자를 치료하여야 한다. 또한 수술후 정기적인 관찰과 평가는 외과의사의 의무가 되어야 하고 문제가 분명해 질 때는 적절히 수정하여야 한다. 이번에 소개한 Mulliken의 치료법은 단순히 기법만을 중시하는 것이 아니라 원칙과 의무, 성장을 고려하는 4차원적 치료이다. 저자들은 이 치료법이 환자들과 외과의사들에게 많은 도움이 되기를 바란다.

• 건축역사연구
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• 제12권4호
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• pp.49-62
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• 2003

Vesely explains, the main source of our confusion and nihilism comes most probably from the ambiguous relationship between modem architecture, technology and aesthetics. Also, to overcome such crucial problems, many theorists recently emphasize to take part in cultural civilization and to preserve creative genes of great culture that is based on our interpretation of 'ethical and mythical nucleus of mankind,' rather than in technical modernization that constitutes a sort of subtle destruction of mytho-ethical nucleus of a society. They for architecture also strongly stress on a mythopoetic imagination and an ontological construction of building, which could make a form symbolic and mythical rather than mathematical and aesthetic representation. On this point, 'myth' becomes a vital idea for constructing and construing architectural form and space. And it is also one of the essential concepts to understand both the motive power of cultural continuation of place and the meaning of architecture. Nevertheless, its meaning and the citation of word in architectural essay are still obscure. It might be because the original concept of myth not only has been lain in the matter of philosophical contemplation. Thus, the intention of the research is focused on lightening the meaning of myth in architectural term. Especially, it is, first, concentrated on interpreting philosopher Ernst Cassirer's reflections which were written in order to emphasize the importance of 'mythical consciousness' for the world's cultural civilization. And, the second, it will continue to interpret the myth as a sign within the semiotic concept of Charles Sanders Peirce, and further to emphasis the significance of mythic signs for the continuance of artistic and cultural idea including architecture. The contents of the paper is not that of architectural planning and design methodology, rather architectural philosophy and epistemology. Nevertheless, in regard to architecture, the research will, against today's un-discriminated use of symbolic motifs and instrumental representation of form, suggest a concrete architectural and aesthetic theory of myth and sign, especially of the relationship between the idea of semiology and the function of cultural continuity.

• 한국컴퓨터정보학회논문지
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• 제19권7호
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• pp.95-102
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• 2014

지표면 아래에는 다양한 구조물들이 매설되어 있으며, 특히 도시가스 배관이나 전기 배선과 같이 문제가 발생할 경우 우리의 안전을 크게 위협할 수 있는 다양한 위험요소들이 존재하고있다. 따라서 다양한 오염물질과 접하게 되는 지하 구조물들은 부식에 대단히 민감하기 때문에 부식의 진행 정도를 정확히 파악하지 못하는 경우 가스 배관의 누설과 같은 대형 사고로 이어질 수 있다. 지금까지는 사람이 직접 지하구조물에 일일이 방문하여 수작업으로 측정하고 기록하는 방식이 주로 사용되었으나, 이 방식은 많은 인적/물적 자원이 요구되어 관리의 연속성이 떨어지게 된다. 따라서 지속적인 관리를 통해 위험요소를 신속하게 발견하기 위한 연구가 필요하며, 본 연구에서는구조물 관리 시스템에 ICT를 결합하여 이동 중인 차량에서 지하구조물에 대한 상태 정보를 무선으로 수집하고 분석하여 신속히 대비할 수 있는 시스템을 제안한다.