• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.238-243
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• 1999

Minimum-fuel and -time orbit transfer are two major goals of the satellite trajectory optimization. In this paper, we consider satellites in two coplanar elliptic orbits when the apsidal lines coincide, and analytically find the conditions for the two-impulse minimum-time transfer orbit using Lambert's theorem. The transfer time is a decreasing function of a variable related to the transfer orbit's semimajor axis in the minimum-time case. In the minimum-time case, there is no unique minimum-time solution, but there is a limiting solution. However, there exists a unique solution in the case of minimum-fuel transfer, fur which we find analytically the necessary and sufficient conditions. As a special case, we consider when the transfer angle is one hundred and eighty degrees. In this case, we show that we obtain the classical fuel-optimal Hohmann transfer orbit. We also derive the Hohmann transfer rime and delta-velocity equations from more general equations, which are obtained using Lambert's theorem. We note the tradeoff between minimum-time and - fuel transfer. An optimal coplanar orbit maneuver algorithm to trade off the minimum-time goal against the minimum-fuel goal is proposed. Finally, the numerical simulation results are given to demonstrate the derived theory and the algorithm.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.526-528
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• 2004

This paper focuses on planning strategies for object interception, especially with minimum time. Herein, the goal is for robot to intercept object with minimum time on a conveyor line that flows to x-axis with respect to world coordinate system. In order to do it, conveyor system needs the algorithms for minimizing time. This objective is achieved by solving about two problems: selection of a minimum-time interception point and planning of an optimal robot trajectory. Herein, the first problem is formulated a minimization of the robot-object interception time.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.193-203
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• 2007

In this paper we consider the inverse minimum flow (ImF) problem, where lower and upper bounds for the flow must be changed as little as possible so that a given feasible flow becomes a minimum flow. A linear time and space method to decide if the problem has solution is presented. Strongly and weakly polynomial algorithms for solving the ImF problem are proposed. Some particular cases are studied and a numerical example is given.

• Journal of the Korean housing association
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• v.20 no.3
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• pp.47-58
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• 2009

Providing an adequate housing to the socially underprivileged with a weak economic base is the most difficult task of housing policies. Korea established minimum housing standards and has used them for housing policies. However, the level of Korean minimum housing standards is far lower than that of foreign minimum housing standards. Thus, this study made a comparative analysis of Korean minimum housing standards with foreign housing standards in various aspects in order to guarantee housing quality of the socially underprivileged in Korea. In particular, the floor area and ratio of small lease homes are minutely examined to present the actual housing standard of the socially underprivileged. The level of Korean minimum housing standards suggested in this paper is very close to that of Japanese minimum housing standard, which is 37.95 $m^2$ for a 3 member family and just above Chombard de Lauw's pathological limit (36.03 $m^2$). As this research is specifically focused on the establishment of minimum floor area standards for the socially underprivileged, further research should be made in consideration of more specific requirements of various groups for the socially underprivileged.

• Journal of Labour Economics
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• v.41 no.4
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• pp.107-131
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• 2018

This paper presents a model for the Minimum Wage Commission's decision process and analyzes the strategic actions of the participants in the process. The Minimum Wage Commission has used two ways of setting the minimum wage. The commission has voted either on the labor's against the management' final proposals or has voted on the public interest commissioners' proposal. According to the model, the minimum wage is determined at a level that is very close to or at a level preferred by the median voter among the public interest commissioners. But the probability of adopting labor or management proposal is ex-ante the same. Empirical evidence from the minimum wage decision process is consistent with the predictions of the model. The probability of adopting the labor's proposal in the minimum wage commission voting is not statistically significantly different from 50%. The model also suggests that the preference of the median voter among public interest commissioners determines the minimum wage level. Since the government appoints public interest commissioners and thus, in fact, the median voters, the government can decide the minimum wage level. This proposition is also consistent with data. The annual growth rate of the minimum wage under the progressive governments is higher than under conservative governments.

• Journal of the Korea Safety Management & Science
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• v.9 no.5
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• pp.111-116
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• 2007

The objective of this paper is to calculate the minimum scale of management for transportation business in order to achieve a form of enterprise. In this study the tracking minimum scale of business is the minimum number of operating trucks. Transportation companies should ensure the number of trucks for a type of business model rather than a means of livelihood model. The method to calculate the minimum number of trucks for the transportation business model can use an approach of either the qualitative and the quantitative technique. This study chooses the quantitative technique to calculate the minimum number of trucks through the analysis of break-even point.

• The KIPS Transactions:PartA
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• v.9A no.4
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• pp.595-602
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• 2002

The watchman routes which an watchman patrols the interior of polygon moving along the route are classified to minimum length or minimum links. The watchman route with minimum links has minimum changes of direction in process. In this paper, we present an algorithm with $O(N^2)$ time for finding the watchman route with minimum links in the weakly visible polygons which have specific property.

• Journal of the Korean Data and Information Science Society
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• v.14 no.3
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• pp.687-696
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• 2003

This article presents a new family of the estimating functions related with minimum distance estimations, and discusses its relationship to the family of the minimum density power divergence estimating equations. Two representative minimum distance estimations; the minimum $L_2$ distance estimation and the minimum Hellinger distance estimation are studied in the light of the theory of estimating equations. Despite of the desirable properties of minimum distance estimations, they are not widely used by general researchers, because theories related with them are complex and are hard to be computationally implemented in real problems. Hopefully, this article would be a help for understanding the minimum distance estimations better.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.9
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• pp.795-801
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• 2005

This paper focuses on planning strategies for object interception by the robotic manipulator on a conveyor system in minimum time. The goal is that the robot is able to intercept object with minimum time on a conveyor line that moves at a given speed. The search algorithm for minimum time solution is given in detail for all possible cases for initial locations of robot. Simulations results show the validity of the given algorithm.

• KCI Concrete Journal
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• v.11 no.3
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• pp.45-52
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• 1999

A Computer-based iterative method is provided for the calculation of minimum thickness values for one-way slabs to satisfy the maximum permissible limits given in the ACI Building Code. An algorithm includes the effects of cracking and time-dependent effects due to creep and shrinkage. Comparison of the calculated minimum thickness values with the current ACI limits is conducted to investigate limitations of the current tabulated minimum thickness. which are constant to a range of design conditions.