• 해양환경안전학회지
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• 제20권4호
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• pp.372-381
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• 2014

2013년 하계 자란만 서부 연안에서 Cochlodinium polykrikoides 적조의 미발생 원인을 화학적 현장관측결과와 기존에 발표된 C. polykrikoides의 생리학적 자료를 이용하여 해석하였다. 조사기간 동안 식물플랑크톤 군집은 규조류가 우점하고 있었으며, Cerataulina pelagica, Chaetoceros spp., Navicula spp. 그리고 Nitzschia spp.가 주요 우점종으로 출현하였다. 자란만 서부 연안의 영양염 농도는 이전의 C. polykrikoides 적조 발생 시기에 비해서 DIP 농도는 유사하였지만, DIN 농도는 낮았다. 특히, C. polykrikoides는 자란만 서부 연안에서 우점종으로 출현하는 규조류들에 비해서 무기 영양염에 대한 반포화상수(Ks)가 낮아 이들과의 종 경쟁에서 불리한 위치에 있는 것으로 보였다. 또한 상대적으로 낮은 DIN 농도를 보인 자란만 서부 연안은 질소에 대한 의존성이 높은 C. polykrikoides가 증식하기 위해서 불리한 환경이었다. 따라서 자란만 서부 연안의 낮은 영양염 환경하에서 무기 영양염 경쟁에 대해 불리한 위치에 있는 C. polykrikoides는 규조류의 번무에 따라 출현이 억제된 것으로 생각된다.

• 한국건축시공학회지
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• 제9권4호
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• pp.111-117
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• 2009

건축공사에서 지하공사는 전체 주 공정으로 전체공기와 공사비에서 큰 부분을 차지하고 있으며, 특히 도심지의 경우 해마다 규모가 증가하고 있다. 현재 현장에서 시공하는 지하옹벽은 많은 기능 인력이 필요하고, 공사기간 측면에서도 불리한 유로폼+솔져시스템에 의하여 공사가 진행되고 있다. 이를 보완하기위해 신소재 거푸집과 신공법이 개발되고 있으며, 공사기간 단축과 원가 절감이 요구되고 있는 실정이다. 따라서 본 연구에서는 건축공사 현장에서 가장 많이 사용되는 유로폼+솔져시스템과 토목공사 현장에서 사용된 무지주 지하옹벽 거푸집 공법을 경제성 측면에서 비교해 보고자 하였다. 연구 결과, 유로폼+솔져시스템이 재료비 측면에서는 유리하나, 노무비 측면에서는 불리한 것으로 나타났다. 하지만 무지주 거푸집의 현장 적용 활성화를 위해서는 재료비의 절감을 위한 추가적인 연구가 필요할 것으로 사료된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.529-536
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• 2003

In domestic case occurrence of cut slopes according to construction and expansion of road is necessary more than 70% of country has been consisted of mountain area. In the case of Kang-won Do, there are much mountains locals in road wiping away a disgrace and expanded and slant is connoting collapse danger of incision side by each kind calamity being urgent. When route alteration enforces disadvantageous road extension, stability examination and processing way about large slope happened are serious. During road extension work in the Kang-won DO secure stability for falling rock of road slope and failure that happen and established suitable reinforcement and countermeasure in reply in necessity. The Slope is divided rock slope and soil slope, and then in order to analysis soil slope apply LEM theory. And rock slope examined stability about stereographic projection and wedge failure. Is going to utilize in reinforcement and failure prevention if it is efficient cutting as reinterpreting stability and secure stability and wish to consider effective and robust processing plan of great principle earth and sand side, and present countermeasure inside with these data hereafter applying suitable reinforcement countermeasure about unstable section.

• 보건행정학회지
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• 제19권2호
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• pp.85-110
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• 2009

The aim of this study was to examine whether health status is different according to employment status and income level in wage-earners. We analyzed wage-earners of 2199 men and 1194 women aged 30-64 years, using data from the 2006 Korean Labor and Income Panel Study(KLIPS). The difference of health status according to employment status and income level was compared with the multiple logistic regression and the standardized concentration index of ill-health. The risk of ill-health was high when waged-earners had low income. The same is true for poor employment status when their employment status was unstable as in manual laborers, irregular workers, temporary, daily workers or part-time workers. furthermore, the wage-earners with lower income and a relatively disadvantageous employment status showed the lowest health status compared to other groups. Ill-health was relatively more concentrated in lower income group and poor employment status. This study identified the existence of health inequality among various employment status of wage-earners. It is suggested that policies that deal with the inequality in social class may have an important impact on the health of the population.

• Wind and Structures
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• 제21권1호
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• pp.41-61
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• 2015

The flutter stability of long-span suspension bridges during erection can be more problematic and more susceptible to be influenced by many factors than in the final state. As described in this paper, numerical flutter stability analyses were performed for the construction process of Zhongdu Bridge over Yangtze River using the commercial FE package ANSYS. The effect of the initial wind attack angle, the sequence of deck erection, the stiffness reduction of stiffening girders, the structural damping, and the cross cables are discussed in detail. It was found that the non-symmetrical sequence of deck erection was confirmed to be aerodynamically favourable for the deck erection of long-span suspension bridges and the best erection sequence should be investigated in the design phase. While the initial wind attack angle of $-3^{\circ}$ is advantageous for the aerodynamic stability, $+3^{\circ}$ is disadvantageous compared with the initial wind attack angle of $0^{\circ}$ during the deck erection. The stiffness reduction of the stiffening girders has a slight effect on the flutter wind speed of the suspension bridge during erection, but structural damping has a great impact on it, especially for the early erection stages.

• International Journal of Contents
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• 제4권3호
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• pp.1-9
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• 2008

The Korean life insurance industry has undergone profound changes, such as the beginning of the variable insurance in July 2001 and the bancassurance enforcement in August 2003. However, little empirical research has analyzed data that includes the bancassurance of life insurance companies operating in Korea. In response to this lack of research, this paper applies DEA (data envelopment analysis) models to measure and decompose their efficiency. We discovered that life insurance companies operating in Korea are a little different in their composition ratio of inputs and outputs, due to the increased variety of distribution channels and new products. We provided efficiency scores, return to scale, and reference frequencies. We also decomposed CCR, BCC, and SBM efficiency into scale efficiency and MIX efficiency. So, we try to investigate whether the sources of inefficiency were caused by the inefficient operation of DMU, disadvantageous conditions, the difference of the composition ratio in inputs and outputs with reference sets, or any combination of the above. Most companies in the sample display had either constant or decreasing returns to scale. The efficiency rankings were less consistent among models and efficient DMUs. In response to this problem, we used the super-efficiency model to rank them and then compared the rankings of the DMUs among the various models. It was also concluded that the availability of panel data, rather than cross-sectional data, would greatly improve the validity of the efficiency estimates.

• 수산경영론집
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• 제13권2호
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• pp.31-48
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• 1982

Though modern banking organs were established in Korea with the Kanghwa Treaty as a momentum, the benefit of financing at that time, which was mainly given to merchants and industrialists and traders, was extremely limited to the fishermen. The fishermen who were out of favor with the benefit of financing of modern banking organs were forced to rely on high interest loans, a category of usury capital, issued by the middlemen (the Kaekju) who lent them the deficit of their necessary funds. The fact was that in the field of fisheries the middlemen who issued usury capital played the leading part in fisheries financing of the Late Yi Dynasty. The middlemen, however, sqeezed a part or all of surplus products and on occasion even necessary products out of the fishermen by means of outward compulsion of economy. Moreover they put the fishermen further in trouble by putting-out system. In order to keep on with the production of aquatic products, the fishermen with little capital and no property established the antinomic rotations with the middlemen whose disadvantageous terms they were inevitably to accept. Thus the middlemen who did business with the fishermen exercised their authority over them, securing a strong activity foundation in the field of fisheries. But the traditional form of the Kaekiu was transformed and gradually declined in the field of fisheries according as the market rules were proclaimed in 1914.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2002년도 학술논문발표회
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• pp.75-80
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• 2002

The purpose of this study is to conduct researches on the aspects of reconstruction and remodeling of low-rise, dilapidated apartment buildings in the provinces, using comparative methodologies, consequently coming up with the findings in the following. 1) Unlike the rebuilding projects in which the movement process tends to be made in a bulk (in a simultaneous manner), it turns out that when it comes to remodeling, it would be advisable to attempt moving the inhabitants as a group either by the size of their residence or by the building. 2) Given the peculiarities of the construction management mechanism, remodeling projects might seem disadvantageous on the part of the management on account of inadequate accumulation of information and experience. Hence, based on the impeccable assessment of the current status of the subject buildings from the phase of planning, its imperative to closely look into and take into consideration a variety of direct and/or indirect factors in advance of the implementation. 3) A series of comparative researches from the perspective of economical efficiency that remodeling projects appear profitable considering the overall costs including financial expenses, varied taxes, and so on that will be eventually brought forth during the reconstruction period, and all the more so when allowing for the consequential effects which they ought to have upon the natural and human resources, environmental and ecological condition, business potentials, etc. Amelioration to be desired on the basis of the findings above.

• 패션비즈니스
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• 제7권2호
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• pp.69-81
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• 2003

Among the various properties of textile fabrics, the moisture-related properties are important for the textile processes or the apparel comfort characteristics. Alkaline hydrolysis results in pitting on the surface of fibers and increases the amount of hydroxyl and carboxyl end groups of the PET molecules on the fiber surface. The purpose of this study is to investigate the moisture-related properties of PET fabrics treated with quaternary ammonium compound/alkaline solution. The wetting and wicking properties of the PET fabrics were measured using the following experiments: contact angle, surface free energy, work of adhesion, vertical wicking height, moisture regain, and frictional static voltage. It was concluded that by the alkaline hydrolysis process, surface hydrophilicity and reactivity were considerably improved especially at lower levels of weight loss% and that the pitting of the fiber surface resulted in at higher levels of weight loss% was disadvantageous in moisture-related properties of PET.

• 터널과지하공간
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• 제8권1호
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• pp.8-16
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• 1998

The first purpose of this study is to verify the application of computer modelling to a enclosed space fire. The second one is to determine temperature distribution for the three different ventilation types in case of a enclosed space fire. The third one is to find out the ventilation direction and ventilation quantity to remove effectively heat and combustion products generated by a fire in variable air volume(VAV) system. Firstly, compared with experimental results of Lawrence Livermore National Laboratory(LLNL), numerical results show good agreements. Secondly, among three different ventilation types, the numerical analyses show the highest temperature distribution in occupied zone(up to 1.8 m from bottom) from firing moment to 100 sec. when supply ducts are placed in ceiling and extract duct is placed close to the bottom on side walls. This is due to disadvantageous position of extract duct in ventilating high temperature air which rise because of buoyancy force. Thirdly, this study finds out effective ventilation direction and ventilation quantity to remove heat and combustion products generated by a fire by using VAV system. $CO_2$ concentration is used as a fire fume removal index. As soon as a fire happens, ventilation direction is changed in order to gather and drive out fire fumes. In case of three times ventilation quantity of ordinary one, $CO_2$ concentration and temperature have begun to decrease at 120 sec. after firing, i.e.fire fumes have begun to be removed.