• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.5
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• pp.1-8
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• 2006

The Five Point Method of KS and Four Point Method of IES are generally used to measure and compute the average illuminance in residential areas. Such methods of measurement should be used exactly according to the characteristics of the space and activities. Therefore, this study evaluated computation methods of the average illuminance in terms of comparing the measured values with simulated ones. The Five Point Method of KS is very closed to evaluate task illuminancefor appreciating activities at the center while the Four Point Method of IES is very closed to a concept of the average illuminance over the space excluding the possible maximum and minimum illuminance values.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.169-180
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• 2019

Shorelines should be extracted with consistency because they are the reference for determining the shape of a country. Even in the same area, inconsistent minimum vertex intervals cause inconsistencies in the coastline length, making it difficult to acquire reliable primary data for national policy decisions. As the shoreline length cannot be calculated consistently for shorelines produced by determining the arbitrary distance between points below 1m, a methodology to calculate consistent shoreline length using the minimum vertex interval is proposed herein. To compare our results with the shoreline length published by KHOA(Korea Hydrographic and Oceanographic Agency) and analyze the change in shoreline length according to the minimum vertex interval, target sites was selected and the grid overlap of the shoreline was determined. Based on the comparison results, minimum grid sizes and the minimum vertex interval can be determined by deriving a polynomial function that estimates minimum grid sizes for determining consistent shoreline lengths. By comparing public shoreline lengths with generalized shoreline lengths using various grid sizes and by analyzing the characteristics of the shoreline according to vertex intervals, the minimum vertex intervals required to achieve consistent shoreline lengths could be estimated. We suggest that the minimum vertex interval methodology by quantitative evaluation of the determined grid size may be useful in calculating consistent shoreline lengths. The proposed method by minimum vertex interval determination can help derive consistent shoreline lengths and increase the reliability of national shorelines.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2A
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• pp.139-148
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• 2011

This paper presents the minimum-cost network selection scheme which determines the transmission instance in the multi-band maritime communication system, so that the shipment-related real-time information can be transmitted within the maximum allowed period. The transmission instances and the corresponding network selection process are modeled by a Markov Decision Process (MDP), for the channel model in the 2-state Markov chain, which can be solved by stochastic dynamic programming. It derives the minimum-cost network selection rule, which can reduce the network cost significantly as compared with the straight-forward scheme with a periodic transmission.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06b
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• pp.197-199
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• 2011

테스팅은 테스트 요구사항을 기반으로 수행하기 때문에 테스트 요구사항의 품질은 테스팅 전체 과정의 품질과 직결된다고 할 수 있다. 그러나 테스트 요구사항에서 고려해야 할 점들은 시스템의 도메인과 목적에 따라 다르기 때문에 양질의 테스트 요구사항이라고 판별할 수 있는 기준을 정하는 것은 어려운 일이다. 본 연구에서는 테스트 케이스와 고장 수목의 최소 절단집합을 각각 정형모델로 변환하여 모델체킹을 함으로써, 테스트 요구사항의 안전성을 측정하는 방법을 제시한다. 테스트 요구사항이 반영된 테스트 케이스는 모델체킹의 대상이 되는 정형모델로 변환하였으며, 고장수목의 최소 절단집합은 CTL 검증 속성으로 변환하여 테스트 케이스에서 생성된 정형모델이 안전성을 만족하는지 만족하는지 모델체킹을 적용하여 확인하였다.

• Korean Journal of Optics and Photonics
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• v.8 no.2
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• pp.88-94
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• 1997

Photographic lenses and an aspheric optical pickup-lens are designed by using damped least-squares(DLS) method. We start optimization with arbitrary initial damping factor. To improve the rate of convergence and the stability in optimization, we apply the special procedure that estimates numerical adequacy of derivative increments of variables to the DLS method. When the initial damping factor is almost equal to the median of series of eigenvalues, the convergence and the stability of the method significantly are improved. Optimized lenses have the performance of each target.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.103-105
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• 2005

현재 UNISYS 네트워크 데이터베이스(Network Data Base, NDB)에서는 엔트리 레코드(entry record)를 배치시키기 위한 방법 중 CALC방식의 DMSCALC 알고리즘을 사용하고 있다. 그러나 이 알고리즘의 특성상 하위 레코드가 과다하게 발생하는 업무의 경우 동일 기본저장 페이지(primary page)에 할당되는 타 엔트리 레코드의 저장 영역에 대한 제한을 유발시켜 오우버플로워 페이지(overflow page)로 이동되고 이에 따라 성능 저하를 가져온다. 본 논문에서는 나눗셈법을 따르는 DMSCALC 알고리즘을 분석 연구하고, 엔트리 레코드가 저장되는 기본저장 페이지의 산출 알고리즘을 개선하여 기본저장 페이지 간 간격을 확보하였으며 개선 전 알고리즘과 비교할 때 기본저장 페이지 사용 율의 경우 최소 $22\%$, 최대 $41\%$에 이르는 성능 향상을 나타내었다. 또한 오우버플로워 페이지 발생률의 경우에도 최소 $47\%$, 최대 $67\%$의 감소 효과를 나타내었다.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.4
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• pp.243-250
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• 2010

Purpose: This study evaluated the effect of different screw tightening sequences and methods on detorque values in a well-fitting implant superstructure. Materials and methods: A fully edentulous mandibular master model and a metal framework directly connected to four parallel implants (Astra Tech) with a passive fit to each other were fabricated. Six stone casts were made with a splinted impression technique to represent a 'well-fitting' situation with the metal framework. Detorque values were measured twice after screw tightening using 20 Ncm. Detorque values and minimum detorque values for three screw tightening sequences (1-2-3-4, 2-4-3-1, and 2-3-1-4) and for two tightening methods (two-step and one-step) were analyzed using multi-way analysis of variance and two-way analysis of variance, respectively, at a .05 level of significance. Results: The mean detorque values for screw tightening sequences ranged from 12.8 Ncm (2-4-3-1) to 13.1 Ncm (2-3-1-4), and for screw tightening methods were 13.1 Ncm (two-step) and 11.8 Ncm (one-step). The mean of mimimum detorque values for screw tightening sequences were 11.1 Ncm (1-2-3-4) and 11.2 Ncm (2-4-3-1 and 2-3-1-4), and for screw tightening methods were 11.2 Ncm (two-step) and 9.9 Ncm (one-step). No statistically significant differences among three screw tightening sequences were found for detorque values and for mimimum detorque values. But, statistically significant differences between two screw tightening methods were found for two values. Two-step screw tightening method showed higher detorque value (P = .0003) and higher minimum detorque value (P = .0035) than one-step method. Conclusion: Within the limitations of this study, the screw tightening sequence was not a critical factor for the detorque values in a well-fitting implant superstructure by the splinted impression technique. But, two-step screw tightening method showed greater detorque values than one-step method.

• 월간 기계설비
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• no.11 s.208
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• pp.41-52
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• 2007

행정자치부가 지난 9월 20일 지방계약법 시행령 개정안을 공포하고 이날부터 시행에 들어갔다. 개정된 시행령은 당초 행자부가 분리발주를 억제하기 위하여 지방계약법 제77조를 개정하여 '공사의 분할 및 분리발주 시에는 행정자치부 장관 등 상급기관에 보고'토록 입법예고 되었으나, 우리협회는 분리발주 활성화를 위하여 '기계설비공사 분리발주 근거 조항인 단서3호는 제외'토록 추진함에 따라 우리 협회의 의견이 반영된 시행령이 개정되었다. 또한 하도급관리계획을 불이행한 원도급업체는 앞으로 부정당업자로 제재받아 입찰참가자격이 최소 1개월에서 최고 6개월 미만까지 제한된다. 이밖에 물가변동과 관련하여 단품슬라이딩제를 도입해 특정자재의 가격이 15% 이상 등락할 경우 계약금액을 조정할 수 있게 했다. 이중 지방계약법 시행령 제 77조 개정 내용의 의의 및 우리 설비건설업과 신.구조문 대비표는 다음과 같다.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.162-167
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• 1993

A mixed deciduous forest community in Mt. Sobaek was studied to determine the adequate number of plots of tree stratum for investigating forest community structure. Twenty l0m $\times$ l0m plots were set up iii the studied forest community, and species area curve. performance curve and statistical method were carried out. According to species-area curve, the minimal number of plots where a given percentage increase in number of plots produced less than the same percentage increase in number of species was eight. The minimal number of plots where a given percentage increase in number of plots produced less than the half of the percentage increase in number of plots was eleven. According to performance curve by importance value of the major species, the minimal number of plots where the dominant species was distinguished from the subdominant species was five. The minimal number of plots where the subdominant species was distinguished from each other was ten. Therefore, ten l0m $\times$ l0m plots seems to give an adequate sample for investigating structure of the studied forest community. Similarity index between the ten plots and total twenty plots was above 90%, and 95% confidence interval of species diversity of the ten plots was $\pm$ 0.073.

• Journal of Korean Society of Steel Construction
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• v.19 no.1
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• pp.15-27
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• 2007

Over the past decade, labor costs have increased relative to the cost of material hardware according to analysts in the construction industry. Therefore, the minimum weight design, which has been widely adopted in the literature for the optimal design of steel structures, is no longer the most economical construction approach. Presently, although connection- related costs is crucial in determining the most cost-effective steel structures, most studies on this subject focused on minimum-weight design or engaged in higher analysis. Therefore, in this study, we proposed a fabrication scheme for the most cost-effective moment-resisting steel frame structures that resist lateral loads without compromising overall stability. The proposed approach considers the cost of steel products, fabrication, and connections within the design process. The optimal design considered construction realities, with the optimal trade-off between the number of moment connections and total cost was achieved by reducing the number of moment connections and rearranging them using the combination of analysis that includes shear, displacement and interaction value based on the LRFD code and optimization scheme based on genetic algorithms. In this study, we have shown the applicability and efficiency in the examples that considered actual loading conditions.