• 한국작물학회지
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• 제54권1호
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• pp.24-28
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• 2009

This study was conducted to evaluate the growth characters and yield components of 18 collected sesame cultivars to get basic information on the variation for the sesame breeding using principal component analysis. All characters except days to flowering, days to maturity and 1,000 seed weight showed significantly different. Seed weight per 10 are showed higher coefficient of variance. Capsule bearing stem length and liter weight showed positive correlation with seed yield per 10 are. The principal components analysis grouped the estimated sesame cultivars into four main components which accounted for 83.7% of the total variation at the eigenvalue and its contribution to total variation obtained from principal component analysis. The first principal component ($Z_1$) was applicable to increase plant height, capsule bearing stem length and 1,000-seed weight. The second principal component ($Z_2$) negatively correlated with days to flowering and maturity by which it was applicable to shorten flowering and maturity date of sesame. At the scatter diagram, Yangbaek, Ansan, M1, M2, M4, M7 and M9 were classified as same group, but M10, Yanghuk, Kanghuk, M5, M6, M12 and M13 were classified as different group. This results would be helpful for sesame breeder to understand genetic relationship of some agronomic characters and select promising cross lines for the development of new sesame variety.

• International Journal of Control, Automation, and Systems
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• 제3권3호
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• pp.493-501
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• 2005

A power plant simulation tool ('PowerSim') has been developed with 10 years experience from the development of a plant simulator for efficient modeling of a power plant. PowerSim is the first developed tool in Korea for plant simulation with various plant component models, instructor station function and the Graphic Model Builder (GMB). PowerSim is composed of a graphic editor using general purpose design software, a netlist converter, component models, the scheduler, Instructor Station and an executive. The graphic editor generates a netlist that shows the connection status of the various plant components from the Simdiagram, which is drawn by Icon Drag method supported by GUI environment of the PowerSim. Netlist Converter normalizes the connection status of the components. Scheduler makes scheduling for the execution of the device models according to the netlist. Therefore, the user makes Simdiagram based on the plant Pipe and Instrument Drawing (P&ID) and inputs the plant data for automatic simulating execution. This paper introduces Graphic Model Builder (GMB), instructor station, executive and the detailed introduction of thermal-hydraulic modeling. This paper will also introduce basic ideas on how the simulation Diagram, based on netlist generated from general purpose design software, is made and how the system is organized. The developed tool has been verified through the simulation of a real power plant.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.924-925
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• 2008

There are many types of grid-connected inverter controllers, PI controller based is the most popular methods. But, a common PI control is produced zero-steady state error and phase delay in sinusoidal reference. Synchronous reference frame or DQ transform based controller is capable for reducing both of zero-steady state error and phase delay is. But DQ transform based controller has cross-coupling component which difficult to analyze the system in single phase model. In this paper, to obtained single phase model of the system, DQ transform based controller is analyzed in two techniques. The first is by neglecting cross-coupling. The second is eliminated cross-coupling component by decoupling method. By these two techniques, single phase model is obtained. Then, the single phase model is analyzed to evaluate its performance in stability and frequency response, through Root Locus and Bode diagram, respectively. MATLAB and PSIM simulation is used to verify the analysis. Simulation result is shown; cross-coupling component has no significant influent to the controller.

• 대한전기학회논문지
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• 제39권11호
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• pp.1174-1182
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• 1990

A hgih efficiency and good dynamic performance drive system of an induction motor is presented in this paper using vector control technique. If the induction motor is driven under light loads with rated flux, the iron loss is excessively large compared with the copper loss, resulting in poor motor efficiency. High efficiency drive of an induction motor can be achieved by adjusting the flux level which leads the total motor loss to be a minimum value. Generally reducing the flux degrades the dynamic performance, but the dynamic performance of the proposed system is also maintained high. If the d-axis is coincident with rotor flux phasor in synchronous rotating reference frame, the stator current can be decoupled as flux component and torque component. At steady state, the developed motor torque is proportional to the product of the flux and torque component. The combination of the two components minimizing the motor loss could be found with numerical method. As the procedure to obtain the optimal combination is too hard, it is found experimentally. The system block diagram is suggested for maximum efficiency control. The proposed system is studied through digital simulation and verified with experiment. The experimental results show the possiblity of a high efficiency drive with good dynamic performance of maximum efficiency control.

• 대한기계학회논문집A
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• 제25권11호
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• pp.1705-1712
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• 2001

Mechanical component has striation with constant width and SEM can estimate fracture type and loading condition. SEM has benefit to fatigue fracture analysis but striation can be observed according to the kind of material and range of crack growth rate and can't. In this case, it needs AFM that can measure 3-dimensional surface profile with resolution of atomic size. In this study. to find fracture reason of torsion-mounted blade in nuclear plant, we estimate the relation between stress intensity factor range and root mean square roughness in 12% Cr steel by AFM and predict in-service loading condition of turbine blade. failure analysis is performed by finite element method and Goodman diagram on torsion-mounted blade.

• 한국자동차공학회논문집
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• 제24권6호
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• pp.716-723
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• 2016

A connecting rod is a crucial part for transmitting an explosive force to the crankshaft in the engine. Stress concentration in connecting rod due to the accumulation of the repeated load may initiate micro crack and result in a crucial break down of the component. Two approaches are adopted to obtain a robust design of connecting rod. Inner and outer array matrix based on combinations of control factors and noise factors are constructed for using Taguchi method. Calculated stress results for each element of matrix are plotted in the Goodman diagram. Robust design approach by Taguchi method reduces stress concentration occurred in small end fillet area of the default model. Variable stress approach using Goodman diagram also confirms a robust design by Taguchi method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.508-513
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• 2006

Anchor bolt in baseplate fastenings on the slab track is an important component to conform placing and safety of fastenings. Due to the way of load transmission control of fastenings, sometimes anchor bolt has to be applied lateral load. So we have to take care for it when we design. Especially, in the case of anchor bolt which is applied loads repeatedly, we have to consider fatigue failure. If parts of machine are damaged in static loads, stress will exceed the yield strength. So parts could be transformed largely. Therefore because they are visible to the naked eyes, we can replace parts before failure. However, because fatigue failure that are invisible to the naked eyes happen unexpectedly, it's very dangerous. To make a reasonable design of anchor bolts, we will analyze them by changing diameters of anchor bolt, quality of insert, initial gap between anchor bolt and insert, the presence of insert, etc. which affect the stresses of anchor bolts. We can get the maximum and minimum amplitude of stress through the modified Goodman diagram or Smith diagram which represents limit of all strengths and stress components to the average stress. We also tried to show the way of examining the expected th life of anchor bolt briefly through considering above.

• 한국지형학회지
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• 제27권3호
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• pp.1-11
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• 2020

A CIA analysis (A-CN-K and A-CNK-FM ternary diagram) indicates that, unlike the general granitic hills of the Korean Peninsula, the chemical weathering of the granitic grus (sandy regolith) in the eastern Jincheon basin is variable in geomorphic site except the Chuncheon basin. In the study area, there are three types of hills, such as; inner hills, linear isolated hills, and outer hills. The weathered mantles of the outer hills and linear isolated hills are weakly altered, whereas the inner hill, the Bonghyeon profile, shows a stronger chemical loss of the compositions approximating saprolite. There are small differences between the outer hills and linear isolated hills. The Geumwang site is considered fresh rock due to a low lever of alteration, although its sampling profile shows sandy weathering mantles. In the profiles of the Masan and Mugeuks sites, the lower part of weathering mantles has not experienced a significant level of component loss, but the upper regoliths have substantially been modified. The alteration of the hills occurs by chemical loss of CaO and Na₂O. K₂O exhibited little variation at all sampling suites and it has not changed into saprolite.

• 한국안전학회지
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• 제39권1호
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• pp.16-26
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• 2024

This study aims to introduce a method for risk assessment analysis aimed at preventing electrical fires within the manufacturing industry. Initially, we provided a functional block diagram illustrating the electrical equipment employed in various processes within a food manufacturing company in Chungcheongbuk-do. Subsequently, we categorized the components of each machine outlined in the functional block diagram and determined the priority of failure for each classified component. Upon implementing the model in the frying process of the food manufacturing company, specific components, including MC, motor, mixer heater, electric wiring, and terminal block, exhibit a risk priority number (RPN) of 40 or higher. This identified an electrical issue within the manufacturing process and environment. Consequently, we propose a methodology to identify latent failure modes that could escalate into fires or systemic issues if not promptly addressed. It is essential to note that while the FMEA presented in this study may not immediately impact food manufacturing, its applicability extends to various workplaces.

• 디자인학연구
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• 제17권2호
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• pp.437-450
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• 2004

컴퓨터 시스템의 발전과 정보를 표현할 수 있는 미디어의 발달은 사용자와 제작자 모두에게 다량의 디지털데이터 속에서 원하는 정보를 어떻게 얻을 것인가 하는 문제를 안겨줬다. 이에 제작자에게는 정보시각화 프로세스의 표준을 제시하고 사용자에게는 효율적인 인터페이스를 제공할 수 있는 연구가 필요하다. 따라서 본 논문에서는 동적 다이어그램과 컴퓨터 소프트웨어의 분석을 통해 정보시각화의 개발과정과 개발결과물을 조사하고 연구하였다. 정보시각화의 주요 개발형식에는 요소, 표현, 인터페이스가 포함된다. 정보시각화물의 개발을 위해서는 첫째, 그래픽을 포함한 다양한 미디어에서 사용되어지는 여러 요소들을 찾는다. 둘째, 3차원 컴퓨터그래픽, 디지털애니메이션 및 가상현실시스템 기술을 통해 효과적으로 데이터를 표현할 수 있는 형식을 찾는다. 마지막으로 원하는 결과를 찾기 위해 컴퓨터 프로그램에서 사용하는 다양한 인터페이스 컴포넌트 중에서 필요한 인터페이스를 선택 적용한다. 본 소고에서는 이러한 세 가지의 주요 시각화개발형식에 관하여 구체적인 예제와 함께 제시하였다.