• 대한기계학회논문집A
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• 제26권6호
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• pp.1053-1059
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• 2002

The purpose of this study is to suggest how the machining technique of constant control of cutting speed can improve precision machining and tool life in high speed machining using a ball end mill. Cutting speed is changed in machining fee form surfaces such as connecting rod die. So, we don't have supreme surface form and tool life on machining. To solve this problem we should settle on optimal cutting speeds in free form surface machining. And, to improve precision machining, We must execute high speed machining methods to output optimum NC data using developed constant control of cutting speed program after modeling by CAD/CAM. In this paper, a comparison was made of the cutting precision and tool life in conventional cutting and those in connecting rod machining applying the program developed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.753-759
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• 2001

The purpose of this study is to suggest the machining technique of the constant control of cutting speed in order to improve precision machining and tool life in high speed machining using ball end mill. Cutting speed is changed in machining free form surface like free form surface. So, we don't have supreme surface form and toll life on machining. The way to solving this problem is that we should be settled to optimal cutting speed in free form surface machining. And, to improve precision machining is executed high speed machining method to output optimum NC data with developed constant control of cutting speed program after modeling of CAD/CAM. In this paper, a comparison was made of the cutting precision and tool life in conventional cutting and those in free form surface machining applying the program developed.

• 한국해양공학회지
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• 제19권1호
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• pp.87-94
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• 2005

This paper investigates the constant-level luffing and time optimal control of jib cranes. The constant-level luffing, which is the sustainment of the load at a constant height during luffing, is achieved by analyzing the kinematic relationship between the angular displacement of a boom and that of the main hoist motor of a jib crane. Under the assumption that the main body of the crane does not rotate, the equations of motion of the boom are derived using Newton's Second Law. The dynamic equations for the crane system are highly nonlinear; therefore, they are linearized under the small angular motion of the load to apply linear control theory. This paper investigates the time optimal control from the perspective of no-sway at a target point. A stepped velocity pattern is used to design the moving path of the jib crane. Simulation results demonstrate the effectiveness of the time optimal control, in terms of anti-sway motion of the load, while luffing the crane.

• 한국전산구조공학회논문집
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• 제16권2호
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• pp.183-195
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• 2003

본 연구에서는 판형태의 압전감지기와 압전작동기가 접착되어 있는 보형태의 스마트구조물의 자유진동제어에 대한 유한요소모형화 방법을 제안한다. 압전재료의 직접압전효과와 역압전효과에 대한 구성방정식을 고려하고 변분원리를 이용하여 스마트보유한요소의 운동방정식을 유도한다. 이러한 2절점 보 유한요소근 등매개변수요소로서 Timoshenko 보이론을 기초로 한다. 따라서, 보형태의 스마트구조물을 제안하는 스마트보 유한요소에 의하여 해석함으로써 전압이 작용되는 압전작동기에 의한 구조물의 제어와 전압을 측정하는 압전감지기에 의한 구조물의 모니터링에 대한 수치적인 시뮬레이션이 가능해진다 이러한 스마트보유한요소와 Constant-gain feed back control 기법을 이용하여 압전감지기와 압전작동기를 이용한 보구조물의 자유진동제어에 대한 유한요소 모델을 제안한다

• 한국안전학회지
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• 제31권5호
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• pp.28-34
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• 2016

When a electric power cable is installed in the air for newly or exchanged working, it is necessary at all time to hold a constant tension for an overhead power cable. And also a pendanted power cable is an extreme job to have work in a high sky. For this reason, the objective of this paper developments working robot for preventing disaster that tension of cable installed automatically power cable to hold a constant. So the working robot works at all the time two tasks for mobil and tension it come into a inference between two tasks, control is difficult. Control methode needs to suppress inference of two tasks. In this paper, for installation of overhead power cable, the scheme and control methode of working robot is presented. the robot work at a same time tow tasks that have hold a constant tension of the power cable and move a constant place while unfasten a winding cable at a drum on a chassis. Working robot consist of three parts with mobile system, tension system and control part. As it is applied the feedback/feedforward control, methode of hybrid control is established to suppress that interference come into between two tasks. The simulation programs is made out using models of mobil and tension system, and a proposed controllers. In accordance with simulation, the model of each systems is discussed to make out proper. And also parameters of controllers is selected a suitable value and the driving performance of robot is evaluated.

• 한국연초학회지
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• 제13권1호
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• pp.13-18
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• 1991

This experiment carried out to review influence of relative humidity, temperature and net weight on cigarette hardness for the uniformal control of cigarette quality. Obtained results are as follows: 1. The difference in the cigarette physical properties of constant hardness control is considerably lower than that of constant net weight control. 2. Contribution rate for cigarette hardness is relative humidity > net weight > temperature. 3. The multiple regression equation of cigarette hardness related with relative humidity, temperature and net weight is calculated as follows.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.135-138
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• 1991

In this study, a variety of characteristics is considered when LIM for transit is driven with acceleration and deceleration. From the characteristics of constant voltage, with V/f ratio fixed, slip frequency is derived. With slip frequency of 12[Hz] and objective velocity of 40[km/h], the robust control characteristics which are generated constant thrust and normal force, except for open-loop control interval, are obtained.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.430-433
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• 1988

An adaptive control system for D.C servo drive is developed via minimum variance control theory. The problem of designing this controller under varying load conditions is discussed. A robust self tuning controller that can track a constant reference and reject constant load disturbance is developed. Simulation study shows that the controller has excellent adaptation, capability as well as transient recovery under load changes.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제4B권2호
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• pp.73-79
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• 2004

For the global microwave market, high RF power or deluxe model is applying for inverter gradually. In this paper, 120[V]/1200[W] high power inverter is proposed and verified by an optimized design of PFM type. Especially the steady power output control was fulfilling at ＋/－ 10[％] input voltage variation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.871-872
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• 2009