• Title/Summary/Keyword: Tow Point

Search Result 45, Processing Time 0.023 seconds

A Study on the Eating Behavior and the Attitude about Weight ’s Control of the High School Girls in Kangwondo (강원도 지역여자고등학생들의 식생활 행동과 체중조절 태도에 관한 연구)

  • 김경희;임양순
    • Journal of Korean Home Economics Education Association
    • /
    • v.7 no.1
    • /
    • pp.29-45
    • /
    • 1995
  • The purpose of this study was to investigate eating behavior and the attitude about weight control of the High School Girls. The questionnaires were completed by 519 girls’ high school students.(lived in city ; 269, in mine region ; 250) The results were as follows: 1. The average stature of them was 159.01${\pm}$5.09cm, the average weight was 51.64${\pm}$6.76kg. 2. In the present body structure of them, the underweight structure was 26.2% the normal weight structure was 58.4% the overweight structure was 15.4%. The present body structure was very different from the recognition of their own body structure. 3. The average point of the eating behavior was 52.07 and that of city(53.62 point) was higher than mine region(50.01 point). 4. The rate of going without breakfast(P<0.05) the frequency of snack(p<0.001) the eating rate of stimulus foods(p<0.05) the interest healthy food life(p<0.05) in two regions showed the significant difference. 5. The point of eating behavior in two regions showed the positive correlation in the economic level, the contentment degree of the present body structure, the conscious healthy condition. But it showed the negative correlation in the rate of going without of breakfast. On observing the difference of the tow regions, it showed the positive correlation to mother’s education career on the negative relation to the experience of the weight control in the city. In the other hand it showed the negative correlation to the recognition on degree of the present body structure in the mine region. 6. The contentment degree of the present body structure showed the negative correlation to the experience of the weight control. Also it showed the negative correlation to the rate of going without breakfast in the city.

  • PDF

Sensor-Based Path Planning for Planar Two-identical-Link Robots by Generalized Voronoi Graph (일반화된 보로노이 그래프를 이용한 동일 두 링크 로봇의 센서 기반 경로계획)

  • Shao, Ming-Lei;Shin, Kyoo-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.12
    • /
    • pp.6986-6992
    • /
    • 2014
  • The generalized Voronoi graph (GVG) is a topological map of a constrained environment. This is defined in terms of workspace distance measurements using only sensor-provided information, with a robot having a maximum distance from obstacles, and is the optimum for exploration and obstacle avoidance. This is the safest path for the robot, and is very significant when studying the GVG edges of highly articulated robots. In previous work, the point-GVG edge and Rod-GVG were built with point robot and rod robot using sensor-based control. An attempt was made to use a higher degree of freedom robot to build GVG edges. This paper presents GVG-based a new local roadmap for the two-link robot in the constrained two-dimensional environment. This new local roadmap is called the two-identical-link generalized Voronoi graph (L2-GVG). This is used to explore an unknown planar workspace and build a local roadmap in an unknown configuration space $R^2{\times}T^2$ for a planar two-identical-link robot. The two-identical-link GVG also can be constructed using only sensor-provided information. These results show the more complex properties of two-link-GVG, which are very different from point-GVG and rod-GVG. Furthermore, this approach draws on the experience of other highly articulated robots.

The estimation of the productivity in adjacent water fisheries (연근해어업 업종별 생산성 추정에 관한 연구)

  • Park, Cheol-Hyung
    • The Journal of Fisheries Business Administration
    • /
    • v.45 no.1
    • /
    • pp.63-77
    • /
    • 2014
  • This study is to estimate the recent changes in total factor productivity of 15 Korean adjacent water fisheries based on Malmquist productivity indices. The study adopted both input and output oriented productivity measures utilizing a hyperbola distance function. In addition to this point, the study also calculated the 95% confidence interval for the various components of the productivities in order to access the statistical significance of estimates using 2000 times of re-sampling process through the smoothed bootstraping. The results of the study showed us that there was 18% reduction in the overall total factor productivity during the study period from 2007 to 2011, which turned out to be 5% of annual decrease in productivity. The study found that the main reason of this decrease in total productivity is about 22% downward shift of a fisheries production function due to recent conditions of a devastated fishing ground. When we evaluated the statistical significance of changes in technical efficiency combining both pure technical and scale efficiency based on the 95% confidence intervals, we could not find any evidence of changes in those components of total factor productivity. When we accessed the productivity of the each of 15 adjacent water fisheries methods, only the large danish seine fisheries showed us about 7% increase in productivity. Even though the large trawling and the large tow-boat trawling revealed no changes in productivity, all of the other 12 fisheries suffered the decreases in productivities.

Nature and Issues of Hospital Management (병원관리학의 본질과 과제)

  • 황인경
    • Health Policy and Management
    • /
    • v.1 no.1
    • /
    • pp.153-160
    • /
    • 1991
  • Hospital Management, as a branch of science, is now in a formative period in Korea. Proper understanding on the scienctific nature and issues of the subject, therefore, is important for both its developement and education of the students. As an academic subject, Hospital Management can be pointed out to have three characteristics, Firstly, when looking it in teleological viewpoint, it is a branch of health science. Ultimate goal of the hospital lies in promoting and keeping health of the people residing in the catchment area in which it places, Secondly, in terms of its contents, Hospital Management can be divided into tow subsubjects ; hospital administrative management and hospital business management. The former stands at the point of looking the hospital as the object of goverment administration, while the latter as the subject of organizational operation. Flanlly, Hospital Management, in its academic appoach, is a science that adopts management theories, what is called, traditional and/or modern. For the settlement and development of the Hospital Management, four major issues were suggested for discussion now and in the future. They include ; (1) boundary between Hospital Management and its related academic fields (2) subdivision of the subject and its contents, (3) activation of study, theortical and empirical, and (4) distinction of the level of lecture among lecfnical, four-year and gradudate courses.

  • PDF

An Experimental Study on the Energy Separation in the Ratio of Nozzle Area of a tow Pressure Vortex Tube (저압용 보텍스튜브의 노즐면적비에 따른 에너지 분리특성에 관한 실험적 연구)

  • 오동진;최정원
    • Journal of Energy Engineering
    • /
    • v.13 no.1
    • /
    • pp.34-39
    • /
    • 2004
  • The process of energy separation in a low pressure vortex tube with compressed air as a working medium is studied in detail. Experimental data of the temperature of the cold and hot air leaving the vortex tube are presented. The variation of the maximum wall temperature along the inner surface of a vortex tube and the temperature distribution in a vortex tube provide useful information about the location of the stagnation point of the flow field at the axis of the vortex tube Analysis of the results enabled to find the optimum ratio of nozzle area and the optimum shape of an orifice. From this optimum geometric setup of a low pressure and big vortex tube the effectiveness of energy separation was better than a high pressure and small vortex tube.

ASESDP : An Efficient Service Discovery Protocol in Pervasive Computing Environments

  • Ma, Qianli;Liao, Minghong;Jiang, Shouxu;Hong, Wan-Pyo;Gao, Zhenguo
    • Journal of information and communication convergence engineering
    • /
    • v.6 no.4
    • /
    • pp.396-404
    • /
    • 2008
  • Service discovery is the technology of finding needed services in networks, and a key point in pervasive computing environments. This paper presents a novel service discovery protocol: ASESDP(AIP and SRR Enhanced Service Discovery Protocol). In ASESDP, tow schemes are proposed to enhance its performance: AIP(Advertisement Information Piggybacked) and SRR(Shortest Reply Route). In AIP, parts of advertisement information are piggybacked in the service reply packet, which makes the advertisement information propagating along the reply path, and spreads its transmission area. In SRR, in order to reduce the service response time, the shortest reply route is chosen to forward the service reply packet to the source node sending the service request. With the theoretical analysis and Glomosim simulation results, it is verified that ASESDP can reduce the number of service request packets, save the response time, and improve the efficiency of service discovery.

An Optimal Damping Control Algorithm of Direct Two-level Inverter for Miniaturization and Weight Reduction of Auxiliary Power Supply on Railway Vehicle

  • Lee, Chang-hee;Lee, Ju
    • Journal of Electrical Engineering and Technology
    • /
    • v.13 no.6
    • /
    • pp.2335-2343
    • /
    • 2018
  • This paper proposes an optimal damping control algorithm of the DTI (Direct Two-level Inverter) to miniaturize and reduce the weight of auxiliary power supply for railway vehicles. The conventional auxiliary power supply for railway vehicles uses a DC-DC converter to maintain the inverter input power from the line voltage smoothly. The proposed topology does not use a DC-DC converter for reducing of manufacturing and maintenance costs. It also proposes a DTI topology removed damping resistors that generate ground signal noise in a certain period. At this time, a resonance phenomenon of DC-link voltage occurs due to variation of the inductive load, and a method of controlling the resonance phenomenon of DC-link voltage is required. In order to suppress the resonance phenomenon of the DC-link voltage, at a point before resonance occurs, this paper introduces an algorithm to suppress the resonance phenomenon of DC-link voltage by compensating the resonance component of the q axis voltage of the synchronous reference frame. The proposed algorithm verifies the effect through simulation and experiment.

Environmental Evaluation for a Photovoltaic-Fuel Cell Hybrid Power System (태양전지-연료전지 복합 전력시스템에 대한 환경평가에 관한 연구)

  • 노경수
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.12 no.3
    • /
    • pp.83-88
    • /
    • 1998
  • This paper presents an overview of environmental evaluation for a photovoltaic-fuel cell hybrid power plant through the Ideal Point approach, which is one of multiobjective decision support systems. Its evaluation is carried out in terms of such tow criteria as land requirement for plant construction and lifetime CO2 emissions, and ten compared with conventional fossil fuel power plants. Fuel cell power system has been proven a viable technology to back up severe PV power fluctuations under inclement weather conditions. Fuel cell power generation, containing small land use, is able to alleviate the heavy burden of large surface requirement of PV power plants. In addition, the PV-fuel cell hybrid power system shows a very little potential for lifetime CO2 emissions.

  • PDF

Efficient Approximation Method for Constructing Quadratic Response Surface Model

  • Park, Dong-Hoon;Hong, Kyung-Jin;Kim, Min-Soo
    • Journal of Mechanical Science and Technology
    • /
    • v.15 no.7
    • /
    • pp.876-888
    • /
    • 2001
  • For a large scaled optimization based on response surface methods, an efficient quadratic approximation method is presented in the context of the trust region model management strategy. If the number of design variables is η, the proposed method requires only 2η+1 design points for one approximation, which are a center point and tow additional axial points within a systematically adjusted trust region. These design points are used to uniquely determine the main effect terms such as the linear and quadratic regression coefficients. A quasi-Newton formula then uses these linear and quadratic coefficients to progressively update the two-factor interaction effect terms as the sequential approximate optimization progresses. In order to show the numerical performance of the proposed method, a typical unconstrained optimization problem and two dynamic response optimization problems with multiple objective are solved. Finally, their optimization results compared with those of the central composite designs (CCD) or the over-determined D-optimality criterion show that the proposed method gives more efficient results than others.

  • PDF

Simplified Control Scheme of Unified Power Quality Conditioner based on Three-phase Three-level (NPC) inverter to Mitigate Current Source Harmonics and Compensate All Voltage Disturbances

  • Salim, Chennai;Toufik, Benchouia Mohamed
    • Journal of Electrical Engineering and Technology
    • /
    • v.8 no.3
    • /
    • pp.544-558
    • /
    • 2013
  • This paper proposes a simplified and efficient control scheme for Unified Power Quality Conditioner (UPQC) based on three-level (NPC) inverter capable to mitigate source current harmonics and compensate all voltage disturbances perturbations such us, voltage sags, swells, unbalances and harmonics. The UPQC is designed by the integration of series and shunt active filters (AFs) sharing a common dc bus capacitor. The dc voltage is maintained constant using proportional integral voltage controller. The shunt and series AF are designed using a three-phase three-level (NPC) inverter. The synchronous reference frame (SRF) theory is used to get the reference signals for shunt and the power reactive theory (PQ) for a series APFs. The reference signals for the shunt and series APF are derived from the control algorithm and sensed signals are injected in tow controllers to generate switching signals for series and shunt APFs. The performance of proposed UPQC system is evaluated in terms of power factor correction and mitigation of voltage, current harmonics and all voltage disturbances compensation in three-phase, three-wire power system using MATLAB-Simulink software and SimPowerSystem Toolbox. The simulation results demonstrate that the proposed UPQC system can improve the power quality at the common connection point of the non-linear load.