• Journal of applied mathematics & informatics
• /
• 제13권1_2호
• /
• pp.183-194
• /
• 2003

We will explain a new method for obtaining the nearly optimal domain for optimal shape design problems associated with the solution of a nonlinear wave equation. Taking into account the boundary and terminal conditions of the system, a new approach is applied to determine the optimal domain and its related optimal control function with respect to the integral performance criteria, by use of positive Radon measures. The approach, say shape-measure, consists of two steps; first for a fixed domain, the optimal control will be identified by the use of measures. This function and the optimal value of the objective function depend on the geometrical variables of the domain. In the second step, based on the results of the previous one and by applying some convenient optimization techniques, the optimal domain and its related optimal control function will be identified at the same time. The existence of the optimal solution is considered and a numerical example is also given.

• 대한건축학회논문집:계획계
• /
• 제34권8호
• /
• pp.129-136
• /
• 2018

Termites are important sub-baits of natural ecosystems and are beneficial insects that are natural decomposer. However, the building materials used by human beings can not coexist with each other on timber which is a termite food. As of 2017, due to fertile forests, warming, and the spread of boilers, termite damage to timber construction is increasingly occurring day by day. Currently, Korea utilizes fumigation, Beit system, preserved wood, etc. of chemical products as termite control measures. But in the case of control measures, timber that has already been eaten by termites can not serve as a structural material and must be repaired. On the other hand, in the case of overseas, Scale of damage to termites the influence on the construction is also large, and a lot of research has been carried out on the prevention methods. In this thesis, investigate such foreign control measures, Would like to suggest a suitable method for Korea.

• 제어로봇시스템학회논문지
• /
• 제4권2호
• /
• pp.220-225
• /
• 1998

In GPS (Global Positioning System) positioning, various measures can be used to select satellites or to evaluate the positioning results. Among these, GDOP (Geometric Dilution of Precision) and RGDOP (Relative GDOP) are the most frequently used. Although these measures are frequently used, the relationship between them is not clearly known. Moreover, the condition number is used as a traditional measure of numerical stability in solving linear equations. Sometimes, the volume of a tetrahedon made by the line of sight vector is used for simplicity. All of these measures share some common properties as well as differences. The relationships between these measures are analyzed in this paper.

• 한국인구학
• /
• 제9권1호
• /
• pp.54-68
• /
• 1986

This study was designed to make a comparative analysis of fertility control policies in developing countries selected from Asia and Latin America. Considering the size and the density of population, the history of the fertility control policy, and the availability of references, eight countries were chosen among Asian developing countries that have adopted the fertility control as an official policy. All of nine countries in Latin America that have adopted family planning as an official policy were included in this study. An attempt was made to formulate an analytical framework to be used for a comparative analysis of fertility control policies. It can be represented by a continuum which consists of individual approaches and structural approaches to fertility control at both extremes. It represents fairly well the controversies between those who advocate family planning and those who advocate measures beyond family planning, but assumes that the two sides of the controversy form a continuum of approaches to fertility control. Various fertility control policies of each country were placed along this continuum and analyzed. The results of the analysis can be summarized as follows: (a) Those countries that have higher population pressure in terms of either the size of population or the population density tend to adopt fertility control policies earlier in time. (b) Those countries that have higher population pressure in terms of either the size of population or the population density tend to adopt more comprehensive measures along the continuum of fertility control policies. (c) Those countries that adopted more comprehensive measures along the continuum seem to have succeeded in reducing their level of fertility more effectively. (d) Developing countries in Asia tend to adopt more comprehensive measures to control fertility than those in Latin American countries. (e) The reduction of fertility in developing countries seems to be associated with both the fertility control policies and the level of socioeconomic development.

• 대한인간공학회지
• /
• 제26권4호
• /
• pp.121-125
• /
• 2007

The objective of this study is to develop short-term prevention measures for minimizing possible human error in nuclear power facilities. To accomplish this objective, a group of subject matter experts (SMEs) were formed, which is consisting of those from regulatory bodies, academia, industries and research institutes. Prevention measures were established for urgent execution in nuclear power facilities on a short-term basis. This study suggests short-term measures for reducing human error on three different areas; (1) strengthening worker management, (2) enhancing workplace environments and working methods, and (3) improving the technologies regulating human factors. Under the leadership of the Ministry of Science and Technology, these short-term measures will be pursued and implemented systematically by utility and regulatory agencies. The details of prevention measures are presented and discussed.

• 한국치위생학회지
• /
• 제9권2호
• /
• pp.73-88
• /
• 2009

The purpose of the study was to provide the basic for the prevention of infection control by analyzing the level of recognition and practice of dental hygiene students. It is important for dental clinic staffs to know and practice infection control measures in favor of effective infection control. Thus, this study conducted an one-month questionnaire survey (during October 2008) for dental hygiene students who ever experienced in 16-week clinical practice, and analyzed total 206 questionnaire forms as collected from them, so that it could determine potential associations between their recognition and practice of infection control and thereby suggest an efficient solution for infection control in dental hygiene. 1. It was found that our students' recognition about infection control averaged $4.49{\pm}.58$ points on the whole, and they were best aware of instrumental disinfection and sterilization among other measures, which was followed by hand washing, extirpation control, post-sterilization management, personal protective outfit and instrumental surface maintenance respectively. 2. It was found that our students' practice of infection control averaged $3.85{\pm}.57$ points on the whole, and they practiced hand washing most actively among other measures, which was followed by extirpation control, post-sterilization management, instrumental disinfection and sterilization, personal protective outfit and instrumental surface maintenance respectively. 3. It was found that our students scored higher mean points in recognition about every measure of infection control than those in practice (t=15.676, p=0.000). Particularly, it was notable that there were significant differences between their mean points in recognition and practice of some infection control measures, such as instrumental surface maintenance (t=15.361, p=0.000), personal protective outfit (t=15.245, p=0.000) and instrumental disinfection and sterilization (t=11.169, p=0.000). But there was least significant difference between mean points in recognition and practice of hand washing (t=5.460, p=0.000). 4. For potential associations between recognition and practice of infection control, it was found that higher recognition was in significantly positive associations with higher practice in every measure of infection control (r=.478, p=.000), such as extirpation control (r=.630, p=.000), instrumental disinfection and sterilization (r=.477, p=.000) and post-sterilization management (r=.433, p=.000). 5. It was found that there were differences in our students' recognition depending upon availability of infection control guideline (t=4.587, p=.011), and there were significant differences in practice depending on necessity of infection control education on a statistical basis (t=2.229, p=.027). Overall, it is found that our dental hygiene students are very likely to practice hand washing and extirpation control, because both of these measures are relatively easy to practice or are considered legally binding.

• Journal of applied mathematics & informatics
• /
• 제7권3호
• /
• pp.787-800
• /
• 2000

In this paper we consider an optimal control system described by n-dimensional heat equation with a thermal source. Thus problem is to find an optimal control which puts the system in a finite time T, into a stationary regime and to minimize a general objective function. Here we assume there is no constraints on control. This problem is reduced to a moment problem. We modify the moment problem into one consisting of the minimization of a positive linear functional over a set of Radon measures and we show that there is an optimal measure corresponding to the optimal control. The above optimal measure approximated by a finite combination of atomic measures. This construction gives rise to a finite dimensional linear programming problem, where its solution can be used to determine the optimal combination of atomic measures. Then by using the solution of the above linear programming problem we find a piecewise-constant optimal control function which is an approximate control for the original optimal control problem. Finally we obtain piecewise-constant optimal control for two examples of heat equations with a thermal source in one-dimensional.

• 제어로봇시스템학회논문지
• /
• 제1권2호
• /
• pp.71-77
• /
• 1995

The control effectiveness and disturbance suppressibility are mainly governed by a left eigenstructure of a system. In this paper, a control algorithm which uses an output feedback eigenstructure assignment scheme is proposed in order that a desired closed-loop system has the specified degree of controllability and/or degree of disturbance suppressibility. To do this, a modal and a gross disturbance suppressibility measures are proposed. A modified version of Hamdan and Nayfeh's modal controllability measure is also presented. The validity and usefulness of the proposed measures and the controller design algorithm are illustrated by designing a controller for a third-order system as an example.

• 한국시스템다이내믹스연구
• /
• 제14권4호
• /
• pp.37-62
• /
• 2013

The purpose of this paper is to find out some clues about effectiveness and implementing timing of the control measures against Foot-and-Mouth Disease (FMD) in Korea. To do that, the case of FMD, which broke out during November 2010 in Korea, is examined and constructed as a system dynamics simulation model. The implications of simulation result are as follows. First of all, it is most effective measure to prevent the movement of vehicle from infected farmhouse to other noninfected farmhouses, which are located far away, in the early stage of FMD diffusion. Secondly, earlier vaccination can be adopted as a reliable means to control the epidemic when FMD spreads widely. Finally, reducing the time to vaccinate the whole noninfected livestock is a little help to restrain the additional infections of FMD.

• 한국컴퓨터정보학회논문지
• /
• 제20권5호
• /
• pp.113-121
• /
• 2015

이 연구는 국내 시스템경비업체의 보안관리 개선을 위한 경영대책의 일환으로 관제시설에 대한 구축 프로세스와 보안관리 방안을 제안한다. 관제시설은 시스템경비의 중추신경으로 현장의 대응체제가 아무리 잘 구축되어 있더라도 관제시설이 장애나 재해로 작동이 중단되거나 관제기계경비원이 위해를 입게 되면 본래의 기능을 수행할 수 없기 때문이다. 관제시설의 구축 프로세스는 공간구조, 기반시설, 관제장치, 관제 솔루션, 운영조직으로 구분하고, 보안관리 방안으로는 물리보안, 정보보안, 인적보안에 대한 대책을 제시한다.