• 한국수학교육학회지시리즈B:순수및응용수학
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• 제19권4호
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• pp.349-361
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• 2012

CAT(0) cubical complexes are a key to formulate geodesic spaces with nonpositive curvatures. The paper discusses the median structure of CAT90) cubical complexes. Especially, the underlying graph of a CAT(0) cubical complex is a median graph. Using the idea of median structure, this paper shows that groups acting on median complexes L(${\delta}$) groups and, in addition, work L(0) groups are closed under free product.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 가을학술발표회 논문집
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• pp.75-86
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• 1992

The elevation of reclamation work in the coastal area for the industrial complex is determined through the investigation and review of marine conditions, drainage plan and fill materials. The embankment to be constructed with crushed stone on the soft soil should be safe against the wave force, immediate and long term consolidation settlement, overturning and sliding due to self-weight and other forces. Because of lack of fill material from the borrow pit, the soft marine clay to be dredged shall be used as the reclamation material. And Paper Drain Board is used as the improvement method for the deep soft clay strata.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제8권1호
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• pp.81-92
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• 2004

Muskhelishvili's complex variable method has been applied to derive exact and closed expressions for Gaursat's functions for the first and second fundamental problems of the infinite plate weakened by a curvilinear hole which is conformally mapped on the domain outside the unit circle by means of rational mapping function. The hole having three poles. The previous work of the authers in this domain is considered as special cases of this work.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(3)
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• pp.123-126
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• 2002

Recently. the effort to make a robot alike human is increasing. The robot helps house work or make a service in restaurant is not a dream. In this paper, we studied home robot serves a beverage. Each 4 beverage has different color. (And robot can serve a drink to master with its color.) It can be applicable to other works need to recognize target object with color. Perhaps, This looks simple but it's idea can be a basis for more complex work.

• 토지주택연구
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• 제6권1호
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• pp.31-39
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• 2015

공동주택 아파트의 조경공간이 변화하고 있다. 지하주차장 조성 면적이 증가하면서 자연지반 면적이 감소되었다. 그 결과 단지 대부분의 조경공간이 인공지반으로 전환되고 있다. 이에 본 연구는 공동주택 식재공간의 현재 토양품질 실태를 분석하여 단지 내 조경공간의 토양품질 관리를 위한 시사점 제시를 목적으로 한다. 이를 위해 토양반입형태가 상이한 3개 사업지구 대상으로 총 17개의 물리성 및 화학성 항목을 조사하여 현 토양품질수준을 진단하였다. 그리고 통계분석(T-test 검증)을 수행하여 지반특성별과 공정주체별 토양 품질의 유의성을 검토하였다. 그 결과, 대규모 지하통합주차장을 갖는 공동주택 단지의 토양수준은 인공토양 식재기준과 비교하여 낮은 것으로 분석되었다. 특히, 가시적 판단이 용이한 물리성은 양호하나 화학성 품질개선이 필요한 것으로 나타났다. 또한 공동주택 지반특성별 토양 품질과 담당공종별 토양 품질의 차이는 없는 것으로 분석되었다(유의수준 5%). 일반적으로 인공지반보다 자연지반의 식재환경이 양호하다는 인식이지만 실제 분석결과 토양품질에 있어서는 자연지반의 토양이 인공지반 토양 품질수준과 동일한 것으로 나타나, 자연지반 토양에 대한 관리기준 도입의 필요성을 제시하였다. 그리고 공종별 담당부서가 상이함에도 불구하고 동일한 수준의 토양이 반입되고 있는 점은 바람직하나 그 토양수준이 상대적으로 낮은 것으로 나타나 품질제고를 위한 관리강화가 필요한 것으로 나타났다.

• 대한산업공학회지
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• 제27권4호
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• pp.413-423
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• 2001

Low back disorders (LBDs) are one of the most common and costly work-related musculoskeletal disorders. One of the major possible risk factors of LBDs is to work with static and awkward trunk postures, especially in a complex trunk posture involving flexion, twisting and lateral bending simultaneously. This study is to examine the effect of complex trunk postures on the postural stresses using a psychophysical method. Twelve healthy male students participated in an experiment, in which 29 different trunk postures were evaluated using the magnitude estimation method. The results showed that subjective discomfort significantly increased as the levels of trunk flexion, lateral bending and rotation increased. Significant interaction effects were found between rotation and lateral bending or flexion when the severe lateral bending or rotation were assumed, indicating that simultaneous occurrence of trunk flexion, lateral bending and rotation increases discomfort ratings synergistically. A postural workload evaluation scheme of trunk postures was proposed based on the angular deviation levels from the neutral position. Each trunk posture was assigned numerical stress index depending upon its discomfort rating, which was defined as the ratio of discomfort of a posture to that of its neutral posture. Four qualitative action categories for the stress index were also provided in order to enable practitioners to apply corrective actions appropriately. The proposed scheme is expected to be applied to several field areas for evaluating trunk postural stresses.

• 한국구조물진단유지관리공학회 논문집
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• 제2권3호
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• pp.176-187
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• 1998

The Dismantlement and Construction of the buildings have the characteristic of floating change with repetition within a Time Schedule which has fixed resources, that is, Manpower, Materials and Equipments, and involve many disaster factors in performing each processes. But as these factors are variable, a work supervisor should be able to understand data analysed distinctive factors of each activities systematically, organizationally, and scientifically, and diagrammatic information media so that he can control any complex and situation beyond forecast. Thus this study is intended to be a barometer of weighing if the existing process schedule has taken security into consideration by making the characteristics of organization and action of Work package per process in a building field with more factors like these into a network system and is intended to minimize construction disasters by systematizing this into a Transformational Network.

• Safety and Health at Work
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• 제13권3호
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• pp.372-375
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• 2022

In the globalized field of safety, health, and well-being, the need to build multi-stakeholder alliances to find solutions to complex challenges is growing. This requires common ground for collaboration, as well as concepts and tools to grasp and manage the areas of interest. Over recent years, Vision Zero has awakened interest and it continues to evolve into many forms of approaches and initiatives, which provide a strategic direction and practical tools for supporting the development of safety, health, and well-being at work. Consequently, there is a need to build a shared understanding of 'zero'. This article reflects the potential of Vision Zero as a bridging concept and an approach for building multi-stakeholder collaboration. Thus, we present a multi-perspective framework of Vision Zero to support further dialoge and collaboration in joint undertakings.

• 산경연구논집
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• 제12권7호
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• pp.15-25
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• 2021

Purpose: The greatest asset to all organizations is the employees and they should be guarded against factors hindering their work ability. Nevertheless, most organizations are always more concerned about making profits to the extent of forgetting their employee's welfare. On this point, this study aims to examine employee's work-related stress and its relationship with work ability. Research design, data and methodology: This study focused on obtaining mostly peer-reviewed works to suggest research findings, assuming that qualitative literature approach allows researchers to explore in-depth information concerning complex issues in a standard life setting. Numerous prior researchers applied their research design in content analysis, especially where various concepts are present for analysis. Results: Based on numerous qualitative textual resources, this study found that human resource practitioners should plan stress management strategies for their employees to apply five kinds of solutions that the current study suggests because it is vital to ensure their wellbeing towards sustaining their performance. Conclusions: All in all, based on the findings, this study concludes that employee's work stress negatively impacts their work ability with affecting their mental health. As a result, there is little doubt that practitioners should regularly monitor the working environment for stress-related factors besides creating a healthy working environment for all employees.

• Korea-Australia Rheology Journal
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• 제15권2호
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• pp.97-105
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• 2003

In the previous paper (Hyun et al.,2002), we have investigated the shape of storage modulus (G') and loss modulus (G") of complex fluids under large amplitude oscillatory shear (LAOS) flow. As the strain amplitude increases, owever, the stress curve becomes distorted and some important information may be smothered during data processing. Thus we need to investigate the stress data more precisely and systematically. In this work, we have obtained the stress data using high performance ADC (analog digital converting) card, and investigated the nonlinear response of complex fluids, 4wt% xanthan gum (XG), 2 wt% PVA/ 1 wt% Borax, and 1 wt% hyaluronic acid (HA) solutions, using Fourier transformation (FT) rheology. Comparing the strain signals in time domain with FT parameters in frequency domain, we could illustrate the sensitivity and importance of FT rheology. Diverse and unique stress patterns were observed depending on the material system as well as flow environment. It was found that they are not the outcome of experimental deficiency like wall slip but characteristics of the material system. When nonlinear response of complex fluids is analyzed, the intensity and phase angle of higher harmonic contributions should be considered together, and the shape of the stress signal was found to be strongly dependent upon phase angle.ngle.