• Journal of Adhesion and Interface
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• v.3 no.2
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• pp.9-16
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• 2002

In the synthesis of water-based polyurethane using self-emulsification process, after being neutralized, polyurethane pre-polymers containing ionic pendant groups are dispersed by simple convective mixing. Preparation of dispersion is followed by chain extension reaction, which is considered as important step for growth of the molecular weight of polyurethane. In this work, pH variations in the aqueous phase were monitored during the chain extension process in the presence of water-soluble diamines. The optimum degree of chain extension and the average particle size in the polyurethane dispersions were examined with varying ionic pendent group contents, type of chain extenders, and feed rate of chain extenders, The initial pH value in the aqueous phase linearly increased and the optimum chain extension point could be obtained from the intersection of two linear lines having different slopes, All average particle sizes before chain extension reaction were almost same, however, the final average particle size increased as feed rates of chain extenders increased, In addition, as the ionic pendant group contents increased, the particle size decreased since the hydrophilicity and hydrodynamic volume increased. As carbon numbers of the chain extenders increased, the final particle size increased significantly. From the results, it was concluded that the chain extension reaction took place among the particles not only in a particle.

• The Korean Journal of Applied Statistics
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• v.30 no.3
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• pp.391-401
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• 2017

This study develops an indicator to manage regional variations of approval rates for long-term care (LTC) service. We used LTC insurance data for grade assessment that include 433,155 applicants from 227 LTC centers across Korea in 2015. The approval rate for each center was defined as the proportion of the numbers of approved applicants out of all applicants. We assumed that the approval rates depended on the characteristics of applicants. We estimated the 'standard' approval rates from a multiple linear regression analysis using the characteristics of applicants as independent variables. The difference between the observed and the standard rates was then defined as an indicator for deviation. A center having a large difference could be considered as a center with a potential error in grade assessment. We also examined if the characteristics of investigators affected the approval rates. We found that the socio-demographic characteristics of applicants and reapplication rate for LTC grade were independent factors affecting the approval rates. Centers having the management indicator values falling outside the middle 95% of the distribution were identified as centers with an error in grading. We expect that this study will contribute to enhancing reliability and equity in LTC grading.

• Journal of Korea Port Economic Association
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• v.26 no.3
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• pp.92-113
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• 2010

The purpose of this study aims to analyse the implied terms of safe berth under Voyage charterparty with the Rebon case. Where the safety of the berth is warranted, but not the safety of the port, then the charterer's obligation is to nominate a berth which can be approached safely from within the port and which was itself, save insofar as affected by hazards or risks which affect the port as a whole or all of the berths within it. This case is an appeal from an order made by the judge dismissing an appeal from a final declaratory award on preliminary issues made by arbitrators. The judge expressed the question for decision somewhat differently as follows: if a specific load port is named in a voyage charterparty and there are several possible berths within that port to which a vessel could be directed to load by the charterers and there is no express warranty in the charterparty of the safety of either the port or the berth to which the vessel is to be directed by the charterers, is the charterparty subject to an implied term that the charterers must nominate a safe berth at that load port?

• Spatial Information Research
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• v.20 no.6
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• pp.129-137
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• 2012

For construction project in extreme cold region, it is essential to establish basic data on the site such as topographical data from the early stage of construction of planning and designing, and it is needed to frequently perform site investigation when necessary. However, extreme cold regions are characteristic of being at long distance and difficult in approaching, and special regions such as Antarctica, in particular, are hard to conduct site investigation. Although a site investigation may be conducted, those who can visit Antarctica are sufficiently limited so that most of the staff may participate in construction without knowledge of the site and increase the risk of errors in decision making or designing. In order to resolve such problems, the authors in this study identified methods of building wide-area topographical data and bedrock classification data of exposed areas via remote sensing and of building precise topographical data on the construction site. Also, the authors attempted to present methods by which such data can be managed and visualized integrally via three-dimensional GIS technology and all the participants in construction can learn sense of field and conduct necessary analysis as frequent as possible. The areas around the Jangbogo Antarctic Station were selected to be the research area for conducting effective integrational management and three-dimensional visualization of various spatial data such as wide-area digital elevation model, ortho-images, bedrock classification data, local precise digital elevation model, and site images. The results of this study may enable construction firms to analyze local environments for construction whenever they need for construction in extreme cold regions and then support construction work including decision making or designing.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.300-307
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• 1998

It is not an easy task for forest managers to make sound decisions on forest management and operations planning because of huge sets of spatial and temporal data and complex decision-making processes involved. However, as an efficient tool, GIS techniques enable them to enhance broad understandings on forest inventory and management conditions. In this study, we developed a GIS model for field use in forest management. In building the model, we have chosen MapInfo version 4.0 as the basic engine of the model. The model also includes an interface module to help forest managers use MapInfo functions easily. It handles MapInfo functions required to manage inventory data and analyze spatial distributions of forest stands. For testing field applicability of the model, we have build field data sets for a district of Chunchun National Forest. Then, we tested functions through quarrying stand attributes and constructing thematic maps. In this paper, the structures and functions of the model as well as the results of field applications are discussed.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.445-460
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• 2017

This study was carried out for three years from 2013 to 2015 to investigate the actual condition of pest control of domestic persimmon organically cultivated farmers, to select environment - friendly pest control materials for major pests, and to conduct field test of established control system. The main cultivated cultivar of the reader farmer of organic cultivation was "Buyou" and sprayed organic agricultural material 9~17 times per year for pest control. The most harmful pests were anthracnose, bugs, persimmon fruit worm, and scales, etc. The control materials used were organic lime sulfur mixture, red clay sulfur, emulsifier, bordeaux solution, and self-made plant extracts using garlic, ginkgo nut and pine tree. The effective materials for controlling anthrax were lime sulfur mixture and red clay sulfur. Garlic oil + citronella emulsion, shrubby sophora seed extract + tea extract was effective to control Riptortus clavatus and Euproctis subflava. When installed 60 ea per 10a of mating disruption trap in a sweet orchard, the fruit setting rate was improved by 30%. The results of field test of control system to control 10 times a year in organically grown persimmons were able to harvest fruit of 70.7%. However, since any kinds of pesticides can not be sprayed during the harvest season in September and October, the damaged by bugs did not decreased, and further research is needed.

• The Journal of Dong Guk Oriental Medicine
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• v.8 no.2
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• pp.25-46
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• 2000

Pain can be evaluated by experimental methods and clinical methods, but due to subjective characteristics of pain, clinical methods are generally used. The clinical pain measurement tools are divided into unidimensional and multidimensional assessment tools. The former include Visual Analogue Scale, Verbal Rating Scale, Numerical Rating Scale, Pain Faces Scale, and Poker Chip Tool and the latter include McGill Pain Questionnaire, MMPI, Pain Behavior Scale, Pain disability index, and Pain Rating Scale. Unidimensional pain scales mainly measure the intensity of pain on the basis of the patient's self report and their simple construction and ease of use enable the invesgator to assess acute pain. Multidimensional pain scales are used to evaluate subjective, psychological and behavioral aspects of pain and because of its comprehensive and confidential properties they are applied to chronic pain. Patient's linguistic and cognitive abilities are major factors to restrain accurate assessment of pain. Although behavioral patterns and vital sign are inferior to self-report in the measurement of pain, they can be useful indexes in those situations. When deciding on a pain-assessment tool, the investigator must determine which aspect of pain he or she wishes to evaluate on the characteristics of the group of patients, their backgrounds, and their communication skills. Making the proper choice will facilitate the acquisition of meaningful data and the formulation of valid conclusions.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.1 s.24
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• pp.21-28
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• 2003

This study was aimed at suggest a proper planning method to select a optimal forest road network in mountains forest using GIS(Geographic Information System). To examine the field applicability, the method was applied to the National Forest at Mt. Kumsan in Namhae-gun, Gyungsangnam-do. The main results from altogether six alternative road route plans were derived from these criteria obtained the alternative route plan No.2 has two layout criteria, longitudinal gradient and earth work volume, and it showed similar pattern of existing forest road network which was designed mainly ground slope and longitudinal gradient. The alternative route plan No.6 has four criteria, longitudinal gradient, earth work volume, investment effect and landscape impact. It was different for the lowest forest road density among the alternatives and the pattern of the forest road layout was radial form, which was also quite different to other alternatives. For optimal forest road network planning, GIS provide the efficient and resonable solutions for decision making to provide the support for evaluation about various alternative road networks. If detailed inventory and relevant data are provided and also clear and objective indicators for evaluations are set up, it could be applied to preliminary analysis and detail planning stage to prevent undesirable effect such the land slide and soil erosion due to inadequate planning for forest road network.

• The Korean Journal of Financial Studies
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• v.10 no.1
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• pp.171-189
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• 2004

외환시장의 효율성을 증대시키고, 기업이나 금융기관들의 원/달러환율 변동위험관리가 보다 원활하게 이루어질 수 있도록 하며, 원/달러 환율과 연계된 다양한 투자전략 구사가 보다 용이하게 이루어질 수 있도록 하기 위하여 미국달러 선물시장과 미국달러 옵션시장에서의 유동성 확대 및 시장 활성화가 요구된다. 본 논문에서는 미국달러 선물시장과 미국달러 옵션시장의 유동성을 제고시키고 시장을 활성화 시키기 위한 방안들을 제시하였다. 미국달러선물의 만기시 최종결제와 미국달러옵션 만기시 옵션매입자가 옵션을 행사할 때 권리행사에 따른 결제는 실물인수도 방식으로 결제되며, 이러한 실물인수도 방식의 결제는 현물환 포지션을 취하여야 하는 불편함과 현물환 거래와 관련된 거래비용 등으로 인하여 투자자들의 시장 참여를 제약하는 주요 요인으로 작용하고 있다. 미국달러선물과 미국달러옵션의 만기시 결제방식을 현금결제 방식으로 바꾸게 되면 헤지거래자 등 투자자들의 참여가 확대되어 시장 유동성이 증대되고 시장이 활성화될 것이며, 차익거래자들도 적극적으로 참여하게 되어 시장의 효율성이 향상될 것이다. 그리고 미국달러선물과 미국달러옵션을 이용한 투자기법 및 투자전략에 대한 투자자들의 이해 수준을 높이고 환율변동위험 관리의 중요성에 대한 기업들의 인식을 제고시키기 위한 적극적인 노력이 요구되며, 중장기적으로 선물회사들의 지점망 확충과 선물거래소 회원사 확대 방안도 모색되어야 할 것이다. 미국달러 옵션은 거래가 매우 부진한 상태이므로 미국달러 옵션시장에서 유동성이 어느 정도 확보될 때까지는 선물회사들의 시장조성 기능 강화가 요구된다.주었다. 둘째, 주가 수익률을 결정하는 유의성있는 요인들은 당기순이익의 증감, 당해연도의 당기순이익의 분포, 자산증가율, 매매 유동성, 매출액 변동, 거래량 추세, 기업크기(시가총액), 과거 1개월간의 주가수익률, 자기자본증가율등으로 나타났다.이 있을 것으로 여겨진다.다중회귀분석에서 각각 일관되게 관찰할 수 있었다. 또한 이러한 결과는 IMF 이후에도 여전히 유지되는 것으로 나타났다.과와는 별개의 PER효과가 여전히 존재하며, 다만 이 PER 효과는 전통적 의미의 일반적으로 낮은 PER종목이 초과수익률을 내는 것이 아니라, 기업규모가 크더라도 그 기업의 개별특성을 고려했을 때 이와 비교해 상대적으로 PER가 낮은 종목에 투자하면 초과수익을 낼 수 있음을 의미한다. 발견하였다.적 일정하게 하는 소비행동을 목표로 삼고 소비와 투자에 대한 의사결정을 내리고 있음이 실증분석을 통하여 밝혀졌다. 투자자들은 무위험 자산과 위험성 자산을 동시에 고려하여 포트폴리오를 구성하는 투자활동을 행동에 옮기고 있다.서, Loser포트폴리오를 매수보유하는 반전거래전략이 Winner포트폴리오를 매수보유하는 계속거래전략보다 적합한 전략임을 알 수 있었다. 다섯째, Loser포트폴리오와 Winner포트폴리오를 각각 투자대상종목으로써 매수보유한 반전거래전략과 계속거래 전략에 대한 유용성을 비교검증한 Loser포트폴리오와 Winner포트폴리오 각각의 1개월 평균초과수익률에 의하면, 반전거래전략의 Loser포트폴리오가 계속거래전략의 Winner포트폴리오보다 약 5배정도의 높은 1개월 평균초과수익률을 실현하였고, 반전거래전략의 유용성을

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.1
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• pp.66-74
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• 1993

Potassium-Graphite Intercalation Compounds(K-GICs) have been prepared from purified natural graphite by transformed two-bulb method with variations of reaction temperature ($T_g:450^{\circ}C$, $400^{\circ}C$, $350^{\circ}C$, $300^{\circ}C$, $250^{\circ}C$).Prepared K-GICs were identified to stage transition process by X-ray diffraction data. At these results, d values of (00l) diffraction at 1 stage and 2 stage were corresponded to $5.35\AA$ and $8.73\AA$ respectively. The stage stability and energy states of K-GlCs were obtained by UV /VIS Spectrophotometric data. We found that the minimum value of reflectance was 2.67 eV(465nm) at $250^{\circ}C$and it's moved to higher energy than original graphite's. And X-ray diffraction and UV /VIS spectrophotometric datas suggest that K-GICs were formed lower stage and many charge carriers exist between C atoms of graphite. And then, these results also provide informations on the electrical and other physical properities of K-GICs.Especially, according to studied reports, d values differ from them of each author, but accurate values were established through this study.