• 농업과학연구
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• 제22권1호
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• pp.110-126
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• 1995

Korean economy has been developed successfully in the course of implementing the five year economic development plans since 1962. The gap of incomes and quality of life between rural and urban area has been widened and it made rural farm laborers drain to urban areas. Therefore the prevailing situation of labor shortage and wage hike in rural area has made farm management deteriorate in recent years. Under the internal and international unfavorable economic conditions, marginal farm land of 66.5 thousand ha has been idled as of end of 1993. The total area outside agricultural development zone with bad farming conditions including irrigation and drainage, and land consolidation for mechanization were estimated at 360.4thousand ha equivalent to 17.5% of the total farm land area in Korea. Considering the topographical conditions of marginal lands, the effective use of marginal lands should be studied from the view point of public interest rather than from the view point of individual economic conditions. Considering the present agricultural economic settings, such as price decrease, unfavourable benefits of farm products, labour shrotage, free trade of farm products and poor physical condition of marginal lands, the institutional and realistical measures for the effective utilization of idle and marginal land should be studied as soon as possible. Detail land use pattern should be surveyed in the areas outside agricultural development zone and have to be classified as orchard farms, grass land, fish culture farms, lawn and ornamental tree farm, sight seeing and leisure farms for urban peoples, special crops production farms and common farms to be developed for farm mechanization. According to the surveyed results, the expected utilization patterns of the idle and marginal lands could be considerd as village common use, farm land base development, leisure farm development, mutual complementary utilization between urban and rural areas, G't purchase and management, credit supply and new extension services, improvement of cropping patterns and sight seeing and leisure farm patterns. For the successful and reasonable management of the marginal lands, the actions such as institutional improvement, prohibition of idle marginal land, enforcement of activities of farm management committee members and land banking system of RDC including development and utilization systems should be included.

• Journal of Periodontal and Implant Science
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• 제33권3호
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• pp.349-358
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• 2003

The success of dental implant therapy relies mainly upon the presence and maintenance of bone adjacent to implant. An 1-year prospective study was performed, upon the patients who were diagnosed as having chronic adult periodontitis, and had been treated with dental implant. The purpose of this study was to measure the radiographic bone level changes proximal to Astra Tech Single Tooth Implants (ATST, Astra Tech AB, $M{\"{o}}lndal$, Sweden) with microthread and Astra Tech TiOblast Implant (ATTB) without microthread supporting fixed partial prosthesis. Measurements were used to determine mean marginal bone loss during the first year of loading, 17 subjects with its partial prosthesis supported by 37 implants were followed up for an 1-year period. The marginal bone loss of implants was positively correlated with the retention factor, microthread($Microthread^{TM}$) in crestal area of ATST. The results were as follows. 1. The mean marginal bone loss of ATST was 0.226${\pm}$0.395mm, while ATTB was 0.440${\pm}$0.360mm. There was a statistically significant difference between ATST and ATTB (p<0.05). 2. The mean bone loss of the upper jaw fixtures was 0.269${\pm}$0.265mm for ATST and 0.529${\pm}$0.417mm for ATTB . There was a statistically significant difference between ATST and ATTB (p<0.05). In the lower jaw the corresponding figures were 0.167${\pm}$0.231mm and 0.313${\pm}$0.214mm, respectively. There was no significant difference between ATST and ATTB (p>0.05). 3. The mean bone loss of ATST was lower than that of ATTB at all sites according to bone quality. There was a statistically significant difference between ATST and ATTB at bone quality type III(p <0.05). In conclusion, the mean bone loss of ATST was smaller than that of ATTB . Therefore, the retention factor of crestal area, microthread ($Microthread^{TM}$) was effective to maintenance of marginal bone level around fixture.

• 대한치과보철학회지
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• 제38권6호
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• pp.806-813
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• 2000

Statement of problems. There are only a few studies available that deal with the clinical behavior of ceromer systems as potential substitutes for metal-ceramic crowns. Purpose. This prospective study was initiated to evaluate the clinical performance of 35 Sculpture crowns after 2 years in service. Material and methods. Thirty five Sculpture crowns were placed for 20 patients (7 men and 13 women). All patients were treated by the same dentist, and all restorations were fabricated by the same dental laboratory. Crown placement involved both the anterior and posterior regions of the dental arches. Patients were evaluated by two examiner at baseline, 12, and 24 months using the CDA quality assessment system in addition to periodontal criteria. Results. Of 34 crowns remaining in the study after 2 years, only one crown had experienced a marginal fracture. The crown was replaced as a result of recurrent caries. All remaining crowns were ranked as either excellent or acceptable for surface and color, anatomic form, and marginal integrity. Conclusion. The 2-year clinical observations and ranking with the CDA quality assessment criteria supported the conclusion that Sculpture crowns may be used in substitutes for metal-ceramic crowns.

• 품질경영학회지
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• 제21권2호
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• pp.194-214
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• 1993

This paper purports to study on interactive fuzzy goal programming model which leads to the compromise solution which the decision maker satisfies through the interactive approach. We also attempted to calculate local proxy preference function from utility function of sum-of-logarithms in connection with marginal rate of substitution and interactive approach for the purpose of applying weight of multiobjective function. In an attempt to grasp compromise solution from fuzzy efficient solution, we decided to take the interactive method and presented stopping rule for this.

• 대한치과의사협회지
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• 제48권2호
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• pp.119-126
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• 2010

Introduction. In this study, we applied the immediate loading to implant using temporary prosthesis, and compared the treatment results by each placement site, amongst pre-loading period. The study was intended to search for occurrence of complications and the amount of marginal bone resorption. Materials and Methods. We retrospectively reviewed the medical records of 99 cases of implants from 29 patients who were treated at Seoul National University Bundang Hospital from September 2003 to September 2008. We grouped all the cases by placement arches and pre-loading periods, and subdivided each group by placement site(anterior/posterior), type of prosthesis(full-mouth cross splinting/Partial multiple splinting, Single). Results. In the cases of anterior maxilla, the average amounts of marginal bone resorption showed $1.71{\pm}0.71mm$ in group 1, and $1.44{\pm}0.69mm$ in group 2, which means they revealed no statistically significant difference between group 1 and group 2(p=0.646). In the cases of posterior maxilla, the average amounts of marginal bone resorption showed $1.25{\pm}0.72mm$ in group 1, and $1.14{\pm}1.15mm$ in group 2, which means they were not statistically significant. In the cases of anterior mandible, there was no cases classified as group 4, but the average amounts of marginal bone resorption in group 3 showed $1.38{\pm}0.79mm$. In the cases of posterior mandible, Group 3 showed $1.39{\pm}0.64mm$, and group 4 showed $1.84{\pm}1.19mm$ as amounts of marginal bone resorption, which means they revealed no statistically significant difference between group 3 and group 4(P=0.210). The survival rate of group1 was 97.14%, 92.1% of group3, and 100% of group 2 and group4. According to each type of prosthesis, each average amount of marginal bone resorption revealed no statistically significant difference in maxi11a(p=0.575) in mandible(p=0.206). Conclusion. It is concluded that the marginal bone resorption and the rate of complications might not be affected by placement sites and pre-loading periods. The marginal bone resorption and the rate of complications might vary as different bone quality of placement site and implant system, diameter, length, etc. It is suggested that the proper placement of immediate loading implants decreases the whole treatment period and any inconvenience occurred to patients.

• 디지털융복합연구
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• 제13권9호
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• pp.137-148
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• 2015

본 연구는 최근 온라인 증권거래에서 이용 비중이 증가하고 있는 MTS 이용자를 대상으로 MTS에 대한 서비스 품질요인이 고객만족도와 고객충성도에 어떤 영향을 미치는 지를 분석하였다. 또한 선행연구에서 제시된 인구 통계학적 특성이 MTS 이용자의 서비스 품질요인에 차이를 나타내는 지를 검증하였다. 본 연구결과를 요약하면 다음과 같다. 첫째, 서비스 품질요인과 고객만족도의 회귀분석 결과 유형성, 반응성, 확신성 및 신뢰성의 네 개 요인이 고객만족도에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 하지만 신속성과 공감성은 유의한 영향을 미치지 않았다. 둘째, 서비스 품질요인과 고객충성도의 회귀분석 결과 유형성, 반응성 및 확신성의 3개 변수는 1% 수준에서 통계적으로 유의하였으며, 정(+)의 부호를 나타내었다. 신속성, 공감성은 5% 수준에서 유의한 정(+)의 영향을 미치는 것으로 나타났다. 하지만 신뢰성은 유의한 영향을 미치지 않았다. 셋째, 서비스 품질요인과 인구통계적 특성 요인 간에 차이가 있는 지를 검증한 결과 확신성과 이용기간, 공감성과 이용기간이 통계적으로 유의한 차이를 나타내었다. 연구결과는 IT와 금융이 어떻게 융합되어 고객가치를 창출하는 지에 대한 새로운 패러다임을 제공할 것이다.

• 한국해양학회지:바다
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• 제21권2호
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• pp.67-77
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• 2016

본 연구에서는 한반도 주변 해역의 해수면 및 수온, 염분의 선형 추세 분석을 위한 종합 회귀 도표를 개발하였다. 현장 관측 자료는 품질 관리 과정을 거쳤으며 객관 분석 자료와의 경험적 직교 함수 비교를 통해 검증하여 사용하였다. 종합 회귀 도표를 통해 기존의 연구 결과들과 유사한 선형 회귀 값을 확인하였고, 1983년부터 2013년 기간동안에서의 5년에서 30년 단위의 변동률을 추가로 제시하였다. 본 연구에서 제시된 정량적 결과가 향후 해양 장기 추세 관련 연구의 기준 값으로 유용하게 사용될 것을 기대한다.

• 대한치과보철학회지
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• 제39권3호
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• pp.243-249
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• 2001

Statement of the problem. The interest in all-ceramic restorations has increased as more techniques have become available. With the introduction of machinable dental ceramics and CAD/CAM systems or Copy-milling systems there is a need for evaluating the quality levels of these new fabrication techniques. Purpose. This study was to evaluate the fitting accuracy of machined all-ceramic crowns made out of an industrially prefabricated feldspathic porcelain. Material and Methods. Three master models with different cutting depth (0.8mm/1.0mm/1.2mm)were produced using a palladium-silver alloy. A total of 36 working dies, 12 of each form, was used for the modellation of prototype resin copings and 36 additional crowns, 12 of each cutting depth, were produced by using the $CEREC^{(R)}2$ system for all crowns. The maginal fit of all 72 crowns was then evaluated on their respective master die at 54 circularly staggered points of measurement per crown under a fixation pressure of 30 N by using a computerized video image system. Results. The medians of the copy-milled $CELAY^{(R)}$ crowns ranged from 29 to $36{\mu}m$. The highest value for the marginal gap was found in group B (cutting depth 1.0mm) at $107{\mu}m$. The median for the $CEREC^{(R)}2$ crowns was found between 43.5 and $70{\mu}m$. The maximum values for all three groups ranged from $181{\mu}m$ to $286{\mu}m$. With $286{\mu}m$ the highest value for marginal gap was found in group C. the Kruskal-Wallis test and multiple comparisons analysis procedure revealed a significant influence of the production technique on the marginal fit in all three groups (p<0,02). Conclusion. 1. The $CELAY^{(R)}$ system is capable to produce all-ceramic crowns with a significantly better marginal fit than the $CEREC^{(R)}2$ system. 2. As far as premolar crowns produced with the $CEREC^{(R)}2$ system are concerned, the cutting depth has a significant influence on fitting accuracy. 3. The production of crowns with an acceptable marginal fit is possible with both systems. However, adhesive luting is recommended for milled feldspathic porcelain crowns.

• 품질경영학회지
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• 제14권2호
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• pp.40-46
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• 1986

The decision maker has the job of torecasting capital investments and operating expenses to aid the decision making in choosing and evaluating present and future alternatives. The estimating function eventually analysis, evaluates and choose the alternatives. The analysis stemmed originally from a preliminary design of some sort, and eventually plans are started to investigate investment possibilites. This study provide the descounted cash flow and the present worth method. Despite any choice of an analytical method, there remains the problem of predicting certain future events. Therefore, these models dealing with optimum plant sizing, equipment replacement, and lease or buy will be discussed.

• Archives of Plastic Surgery
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• 제49권4호
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• pp.473-478
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• 2022

Background We investigate the effect of involutional blepharoptosis (IB) surgery based on dry eye symptoms by analysis using objective and subjective measures. Methods We recorded various parameters from patients that underwent levator advancement surgery for IB, totaling 125 eyes (total 65 patients, 5 unilateral, 60 bilateral). Subjective assessment comprised a questionnaire on dry eye-related quality of life score (DEQS), a summary score calculated from DEQS, and six-grade evaluation, the patient's own measure of eye comfort. Objective assessment comprised marginal-reflex distance-1 (MRD-1), measurement of tear film breakup time, and superficial keratopathy (SPK) existence by slit lamp microscope. Results Subjective assessments showed that IB patients had improvement of dry eye symptoms and eye comfort when surgery increased MRD-1. On the other hand, objective assessments showed that the presence of SPK is suspected when the postoperative MRD-1 level is 3 mm or higher. Conclusion IB surgery must not only increase MRD-1 value, but also to perform maintenance of the appropriate ocular surface condition. From our parameters, we suggest postoperative MRD-1 value should be maintained at < 3 mm to safe and effective of IB surgery.