• 암석학회지
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• 제26권3호
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• pp.255-269
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• 2017

여러 분야에서 높은 관심을 받고 있으며 무엇보다 지질학적으로 희소성과 순수성을 지닌 독도 천연보호구역의 해빈자갈퇴적층(몽돌 해변)을 대상으로 5년간 외부에서 유입된 역 이 얼마나 분포하는지에 대해 모니터링 하였다. 연구 지역인 동도 선착장 인근 및 서도 어민 숙소 인근 해빈자갈퇴적층에서, 주로 발견되는 몽돌의 종류에는 독도에서 직접적으로 기원한 것으로 판단되는 현무암, 조면암류, 응회암류와 외부에서 유입된 것으로 판단되는 화강암, 유문암, 편마암, 규암, 대리암, 그리고 콘크리트가 있다. 2011년과 2016년의 외래 역 데이터를 비교해 보면 동 서도에서 암종의 변화는 발견되지 않았으며, 각 지역에서 가장 빈번하게 발견되는 외래 역의 순위 역시 동도에서 화강암, 콘크리트, 편마암, 그리고 서도에서 콘크리트, 편마암, 화강암 순으로 동일하다. 그러나 동도와 서도의 전체 조사 면적에 대한 외래 역 면적의 비율은 다소 감소했다. 기존 시설물의 파괴와 외래 건축 자재 유입이 해빈자갈퇴적층에 존재하는 외래 역에 대한 주요한 유입 경로로 예상되는 가운데, 전체적인 오염도가 감소했다는 점은 연구기간 동안 외래 역 유입에 대한 관리가 대체로 개선 또는 최소한 악화되지 않았다는 점을 지시한다. 한편 지속적인 낙석이 몽돌의 분포에 영향을 끼친 것으로 판단되며, 낙석 영향에 대한 지속적인 평가가 요구된다.

• 농촌계획
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• 제15권4호
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• pp.19-32
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• 2009

This research has a significant meaning to break from the urban ecology-oriented biotope research and realize the importance of rural landscape as a reserve area for systemizing the types of rural biotope. The results are as follows. First of all, items for classification of 16 rural biotope areas are designed and total 9 itmes in slope from spatial structural point of view and 7 items in minute-variety from functional point of view. Also, as the result of on-site research on case areas based on classified items, there are 46 types of rural biotope such as coniferous forest, hedgerow and so on. For example, it is proven that uncultivated stripe showed the most frequent emergence. As a result of cluster analysis of average linkage method between clusters, 12 clusters are classified as a clusters and 13 biotope types are re-corrected and complemented through brainstorming process and then total 12 clusters are selected as final rural biotope type groups. As a rural biotope type cluster and character analysis according to types based on on-site research and documentary survey, for example, it is analyzed that the ratio of transmissible covering ratio is 100%, the ratio of green coverage is 90% in 'woodland in cultivated area biotope type cluster'.

• Computers and Concrete
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• 제15권5호
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• pp.833-845
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• 2015

In the world total boron reserve rating, Turkey is taken place on the first rank, meeting the demand of refined mineral and main boron chemicals. Development of the new boron products and production technologies, spreading the using area of the boron are the study topics which must be finically discussed. In this study, with the help of colemanite taken in ratio as (0%, 7.5%, 12.5%, and 17.5%) by being mixed by the cement, surfaces of the pumice aggregates have been covered. Permeability of the samples has been investigated by producing lightweight concrete with 400 dose with the help of aggregates covered with colemanite. For this, the experiments of water absorption, capillary water absorption, depth of penetration of water under pressure and rapid chloride permeability have been performed. In addition, analyses of the thin section of covered and uncovered pumice aggregates and SEM (Scanning Electron Microscope) have been investigated. When the control samples produced with the covered aggregates and concretes produced with colemanite covered aggregates are compared each other, it has been determined that special lightweight concretes whose values of capillary water absorption experiment, depth of penetration of water under pressure experiment and rapid chloride permeability are low can be produced.

• Nutritional Sciences
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• 제9권3호
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• pp.195-200
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• 2006

We surveyed Korean pregnant women who participated in the Maeil mothers' club and factory tour from March to April, 2004 and assessed volunteers' hemoglobin (Hb) levels. The average Hb level of 747 subjects was $11.5{\pm}1.5g/dl$ and anemic subjects were 268 women, 35.9% of total subjects. The ratio of anemic subjects was 42.9% in the first trimester, 43.6% in the second trimester and 29.1 % in the third trimester. About 87.9% of subjects began to take health foods after conception. Seventy nine percent of subjects took iron supplement as one of health foods and 73.8% of them began it in the second trimester. The results of this study showed that health foods were more effective than iron supplement alone in improving the iron status of Korean pregnant women. Therefore, the better improvement effects are expected when pregnant women begin health food-based approaches as early as possible before pregnancy to improve pre-pregnancy iron reserve.

• 무역상무연구
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• 제17권
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• pp.93-125
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• 2002

This paper aims to find a reasonable solvency margin system in non-life insurance industry and also to evaluate the appropriateness of the current solvency margin regulation system in Korea. The current solvency margin system in Korea, based on EU's solvency margin model, was introduced during the 1997 financial crisis. The solvency requirement is not based on non-life insurer's risk, but simply on written premiums. The current solvency margin for general insurance, such as fire, marine, and automobile insurance, is determined by the greater between a premium-based amount and a claim-based amount, where the premium-based solvency margin is calculated by multiplying the net written premium for the preceding year by the premium based solvency margin ratio. Also, the amount of solvency margin for long term insurance is set at 4% of the policy reserve of the long term insurance. Still, there exist many differences between the current solvency margin regulation system in Korea and EU's model. This paper focuses on the rationality of the solvency margin regulation system, and compares the current system in Korea with EU's model and the RBC(Risk Based Capital) system in U.S. and Japan. Finally, this paper suggests a more specific and reasonable solvency margin system to be developed in Korea.

• The Journal of Asian Finance, Economics and Business
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• 제7권10호
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• pp.1-8
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• 2020

The objective of the study is to investigate the effect of growth opportunities on capital structure and dividend policy in Indonesia. The study employs panel data of companies listed on Indonesia Stock Exchange that distribute dividends from 2007 to 2017. Fixed and random effect regression models are used. Findings based on growth opportunities on capital structure and dividend policy in Indonesia are in line with the existing theory (i.e., contracting theory). Growth opportunities have a significant negative correlation with debt ratio and dividend yield, which suggests that firms with high growth opportunities are discouraged to generate debt to resolve underinvestment and asset-substitution problem. Firms with more investment opportunities tend to adopt a low dividend payout policy because the cash flows will be used up for investment. The positive impact of firm size on leverage is due to the low bankruptcy risk and cost of a large company. Profitability has a positive impact on the dividend policy because profitable companies can reserve larger free cash flows and, thus, pay higher dividends. The positive influence of ownership on leverage is interpreted by the unwillingness of majority stockholders to commit to equity financing in order to avoid reducing the ownership and preserve control of the company.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.823-825
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• 1996

This paper proposes a preventive maintenance scheduling system which is a user-friendly decision-making support system. The objective of the development of the package is to supply KEPCO's working experts with a useful tool for gaining a practical maintenance schedule. This program based on the MS Windows is made up of two main modules. The first is an interactive decision-making support module(IDSM). The main objective of this module is to provide various useful text and graphic information to users, and enable practicing engineers with sensitivity analysis of a targeting maintenance schedule. The second is a mathematical optimization module(MOM). In this module, the objective function of levelizing net reserve ratio with daily time-increment is optimized using the relaxation method.

• Structural Engineering and Mechanics
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• 제19권2호
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• pp.185-198
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• 2005

In the design of reinforced concrete beams, it is a standard practice to use the yield stress of the steel reinforcement for the evaluation of the flexural strength. However, because of strain hardening, the tensile strength of the steel reinforcement is often substantially higher than the yield stress. Thus, it is a common belief that the actual flexural strength should be higher than the theoretical flexural strength evaluated with strain hardening ignored. The possible increase in flexural strength due to strain hardening is a two-edge sword. In some cases, it may be treated as strength reserve contributing to extra safety. In other cases, it could lead to greater shear demand causing brittle shear failure of the beam or unexpected greater capacity of the beam causing violation of the strong column-weak beam design philosophy. Strain hardening may also have certain effect on the flexural ductility. In this paper, the effects of strain hardening on the post-peak flexural behaviour, particularly the flexural strength and ductility, of reinforced normal- and high-strength concrete beams are studied. The results reveal that the effects of strain hardening could be quite significant when the tension steel ratio is relatively small.

• 한국농촌건축학회논문집
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• 제21권2호
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• pp.35-42
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• 2019

There are 17,427 reservoirs in Korea, of which about 96% were built before the mid 1980s. Therefore, aging is severe and reinforcement are necessary. In addition, aged reservoirs, which are more than 50 years old, account for 70% of the total. Therefore, there is a problem such as the collapse of the reservoir and the decrease of the storage capacity due to progress of aging with time. The grouting method using cement is mainly used as maintenance and reinforcement method of old reservoir. However, the grouting method using cement has engineering and environmental problems. In order to solve the engineering and environmental problems of cement grouting method, an eco-friendly grouting material was developed that mixes circular resource grouting binder, high molar ratio sodium silicate and colloidal silica. The engineering and environmental properties of the developed injection materials were evaluated by conducting gel time, homo-gel strength, sea water resistance test and environmental stability evaluation. Also, examined the possibility of replacing OPC existing aged reservoir reinforcement methods. As a result, it was found out that it was better than the conventional cement method in terms of engineering and environment. However, since this study is the result of laboratory test, it is necessary of verify the application at field of aged reservoir.

• The Journal of Asian Finance, Economics and Business
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• 제8권3호
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• pp.731-740
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• 2021

This research aims to investigate the determinants of real effective exchange rate in emerging ASEAN countries, including Indonesia, Malaysia, Philippines, Thailand, and Vietnam. The research was conducted by using quarterly time series data set from 1980Q1 to 2020Q3. Cointegration and the error correction model (ECM) methods were applied to test the long run and short run relationship of the real effective exchange rate and its determinants. The results indicate that the ratio of foreign direct investment to GDP and the government spending have significantly positive impact on real effective exchange rate in the Emerging ASEAN countries. The trade opening had influencing real effective exchange rate in most the Emerging ASEAN countries, except Vietnam. In addition, the international reserve (INR) had significant long-run impacts variables on real effective exchange rate in Malaysia, Thailand and Vietnam. In the short run equilibrium, the error collection term suggest that Indonesia and Malaysia are the fastest speed adjustment to equilibrium. In addition, the term of trade influence the real effective exchange rate in Indonesia, Malaysia, and the Philippines but it is not in Thailand and Vietnam. However, FDI is a major factor of the real effective exchange rate in Vietnam, but not for other countries.