• 정보처리학회논문지A
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• 제17A권2호
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• pp.103-112
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• 2010

클러스터 센서 네트워크는 여러 개의 중심 노드 주위에 다른 입력 노드들이 밀집된 분포를 보이는 센서 네트워크이다. 최소 스타이너 트리는 스타이너 포인트들을 도입하여 모든 입력 노드들을 최소 비용으로 연결하는 트리이다. 본 논문에서는 센서 노드와 베이스 스테이션의 연결인 간선들을, 클러스터 내에서와 클러스터 사이에서 각각 생성하고, 이를 이용하여 근사 최소 스타이너 트리를 반복적으로 생성하여, 단축된 길이의 클러스터 센서 네트워크를 구성하는 방법을 제안한다. 실행 시간 복잡도가 O($N^2$)인 제안된 방법으로 생성된 클러스터 센서 네트워크들은, 본 논문의 실험에서 유클리드 최소 신장 트리 방법의 네트워크들과 비교하여 생성 시간이 1170.5% 증가하였으나 최소치보다 0.1% 증가된 길이의 네트워크는 20.3%의 증가된 시간에 생성이 가능했다. 이 클러스터 센서 네트워크의 평균 길이는 유클리드 최소 신장 트리 방법과 비교하여 최대 3.7%, 평균 1.9% 감소되었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.44-47
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• 1996

Bang-bang control law provides the optimal solution for a minimum-time control problem, but ignores the intermediate path except for the initial and final points. In this paper, a near minimum-time suboptimal fuzzy logic controller is introduced that can control the intermediate path. A dynamic model for a system is established using the average dynamics method of linearization. System model is continuously updated over the control time periods. This makes it suitable for high speed or variable payload applications. Bang-bang control theory is modified and used to derive the preliminary control law. A fuzzy logic algorithm is then applied to adjust and find the best solution. The solution will provide the suboptimal minimum-time control law which can avoid obstacles in the workspace.

• East Asian mathematical journal
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• 제5권1호
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• pp.95-110
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• 1989

In a general variance component model, nonnegative quadratic estimators of the components of variance are considered which are invariant with respect to mean value translaion and have minimum bias (analogously to estimation theory of mean value parameters). Here the minimum is taken over an appropriate cone of positive semidefinite matrices, after having made a reduction by invariance. Among these estimators, which always exist the one of minimum norm is characterized. This characterization is achieved by systems of necessary and sufficient condition, and by a cone restricted pseudoinverse. In models where the decomposing covariance matrices span a commutative quadratic subspace, a representation of the considered estimator is derived that requires merely to solve an ordinary convex quadratic optimization problem. As an example, we present the two way nested classification random model. An unbiased estimator is derived for the mean squared error of any unbiased or biased estimator that is expressible as a linear combination of independent sums of squares. Further, it is shown that, for the classical balanced variance component models, this estimator is the best invariant unbiased estimator, for the variance of the ANOVA estimator and for the mean squared error of the nonnegative minimum biased estimator. As an example, the balanced two way nested classification model with ramdom effects if considered.

• 지역사회간호학회지
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• 제20권1호
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• pp.105-111
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• 2009

Purpose: The purpose of this study was to identify minimum datasets for ulcer assessment and to map the minimum datasets to paper-based nursing records for pressure ulcer care in homecare setting. Methods: To identify minimum datasets for pressure ulcer assessment, the authors reviewed four guidelines for pressure ulcer care. The content validity of the minimum datasets was assessed by three homecare nurse specialists. To map the minimum datasets to nursing records, the authors examined 107 pressure ulcer events derived from 45 pressure ulcer patients who received home nursing from two hospitals in Gyeonggi Province. Results: The minimum datasets for initial assessment were anatomical location, stage, size, tissue, exudate, condition of periwound skin, undermining, odor, and pain. 'Location' was recorded best, accounting for a complete recording rate of 98.1%. 'Exudate' and 'pain' showed the poorest record, accounting for 2.8% and 0%, respectively. The minimum datasets for progress assessment were wound size, tissue, and exudate, each accounted for 31.8%, 2.8%, and 4.7%, respectively. Conclusion: This study concluded that data on pressure ulcer assessment was not sufficient homecare and it can be improved by adopting minimum datasets as identified in this study.

• East Asian Economic Review
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• 제24권3호
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• pp.253-273
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• 2020

This paper investigates the impact of the effective minimum wage, defined as the log difference between the minimum and the median wages, on wage inequalities in the OECD countries. Unlike the previous studies that focus on single countries in which the minimum wage has no cross-sectional variation and rely instead on within-country variations of wage distribution across regions or socio-economic characteristics, we use a country panel that allows for both cross-sectional and time-series variations in minimum wage. We also control for more factors than in the previous studies whose absence may cause endogeneity. Our results confirm the previous findings that increases in minimum wage alleviate the wage inequality at the lower tail of the wage distribution, while having little effect at the upper tail. The estimated effect is larger for women than for men, which is consistent with the fact that the share of workers who are directly affected by the changes in minimum wage is bigger among women than men. An application of the IVs of Autor, Manning and Smith (2016) supports the robustness of our findings.

• 노동경제논집
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• 제39권4호
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• pp.31-56
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• 2016

본 논문은 최저임금의 사업체 내 임금압축 효과를 다룬 것이다. 분석 결과 사업체 내 최저임금 비중의 증가는 사업체 내 임금분포를 압축시키는 것으로 나타났다. 또한, 최저임금 비중이 큰 사업체일수록 사업체 평균임금이 낮아지는데 이때 고임금 그룹의 하락폭이 저임금 그룹보다 더 크게 나타나며, 저임금 대비 고임금 근로자의 상대임금도 최저임금 비중이 큰 사업체일수록 작아지는 것을 확인할 수 있었다. 본 논문은 다음과 같은 것을 시사한다. 최저임금 인상은 직접적으로는 저임금 근로자의 임금을 상승시키며, 간접적으로는 고임금 근로자의 임금을 하락시키거나 상승폭을 둔화시켜 결과적으로 임금분포를 압축시킨다. 따라서 정책적으로 최저임금의 인상은 임금 불평등도를 낮추는 효과를 얻을 수 있을 것으로 기대된다.

• 대한수학회논문집
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• 제23권4호
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• pp.541-548
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• 2008

For a completely bounded linear maps between operator spaces, we introduce numbers which measure the degree of injectivity and subjectivity. The number measuring the injectivity is an operator space analogue of the minimum modulus of a linear map in normed spaces.

• East Asian mathematical journal
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• 제32권1호
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• pp.35-41
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• 2016

We introduce formal symbols of product type and of minimum type and show that the formal power series representation for $e^p$ is a formal symbol of product type, where p is a formal symbol of minimum type.

• Journal of the Korean Statistical Society
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• 제31권2호
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• pp.213-228
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• 2002

Asymptotic properties of minimum distance estimators for the parameter involved for a class of stochastic partial differential equations are investigated following the techniques in Kutoyants and Pilibossian (1994).

• Korean Journal of Mathematics
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• 제27권4호
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• pp.831-841
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• 2019

A Radiocoloring (RC) of a graph G is a function f from the vertex set V (G) to the set of all non-negative integers (labels) such that |f(u) - f(v)| ≥ 2 if d(u, v) = 1 and |f(u) - f(v)| ≥ 1 if d(u, v) = 2. The number of discrete labels and the range of labels used are called order and span, respectively. In this paper, we concentrate on the minimum order span Radiocoloring Problem (RCP) of trees. The optimization version of the minimum order span RCP that tries to find, from all minimum order assignments, one that uses the minimum span. We provide attainable lower and upper bounds for trees. Moreover, a complete characterization of caterpillars (as a subclass of trees) with the minimum order span is given.