• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1891-1896
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• 2004

The present article proposes a new droplet collision model including the stretching separation regime and the formation of satellite droplets. The new model consists of a several equations to calculate the post-collision characteristics of colliding droplets and satellite droplets. These equations are derived from the energy balance of droplets between before and after collision. For binary collision of water droplets, the new model shows good agreement with experimental data for the number of satellite droplets. Nevertheless, it is thought that, in order to guarantee the generality of the new model, the improvements should be performed to consider the effects of the bouncing and the reflexive separation, which is essential process in the collision of hydrocarbon droplets.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.899-904
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• 2004

Multibody dynamics formulation has been developed based on relative cartesian coordinates for subsystem analysis. Relative cartesian coordinates are defined with respect to a reference body of a subsystem. Relative cartesian formulation inherits the same merits of absolute cartesian formulation, such as generality and easy implementation. Two methods have been applied. One is Largrange Multiplier Elimination method and the other is independent coordinate method. A 1/4 car simulation has been carried out to verify the formulations. Since both methods provide identical results, it proves the validity of the formulation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.176-184
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• 2003

Railway sign(graphic sign, diagraphics) designs require good recognition with universality to transmit accurate and speedy information as they connect people around the station and other transport systems. An important point of signs is how to design and deliver the contents to the viewers as a communication service tools. It needs to establish design guidelines with standardization and unified system to show their contents and images clearly like common language with visuality, attractivity and generality. These requisites are important for both aesthetics legibility and unified standards to maximize the effectiveness of pictograms for the use of the general public, who require systematic suggestion and management.

• 약학회지
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• 제27권2호
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• pp.125-131
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• 1983

Whether ($AB_{w}$) may be neglected against ($A_{w}^{+}$) in the calculation of the extraction coefficient of ion-pairs was criticized by both experiments and theoretical consideration, where ($AB_{w}$) and ($A_{w}^{+}$) mean the molar concentration of ion-pair AB and cation $A^{+}$ in the aqueous phase. Ion-pair complexes were partitioned between phosphate buffer (pH 7.4) and n-octanol. Tetrabutylammonium, isopropamide and methylene blue were selected as cations and benzoic acid, p-toluenesulfonic acid, salicylic acid and taurodeoxycholic acid were selected as counter ions (anions). As a result, conventional methods which assume no existence of ($AB_{w}$) were proven to lack generality. The equation proposed in my earlier report was confirmed to be valid as a general method.

• International Journal of Control, Automation, and Systems
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• 제6권1호
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• pp.101-108
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• 2008

The transposed Jacobian is proposed to transform the control space from task space to joint space, in this paper. Instead of inverse Jacobian, the transposed Jacobian is preferred to avoid singularity problem, short real time calculations and its generality to apply for rectangular Jacobian. On-line Jacobian identification is proposed to cancel parametric errors produced by D-H parameters of manipulator. To identify Jacobian, the joint angles and the end-effector position are measured when tracking a desired trajectory in task space. Stability of control system is analyzed. The control system is simulated for position control of a two-link manipulator driven by permanent magnet dc motors. Simulation results are shown to compare the roles of inverse Jacobian and transposed Jacobian for transforming the control space.

• 전자공학회논문지B
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• 제29B권3호
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• pp.6-15
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• 1992

This paper proposes a method for the global optimization of redundancy over the whole task period for a kinematically redundant robot. The necessary conditions based on the calculus of variations for an integral type cost criterion result in a second-order differential equation. For a cyclic task, the periodic boundary conditions due to conservativity requirements are discussed. We refine the two-point boundary value problem to an initial value adjustment problem and suggest a numerical search method for providing the conservative global optimal solution using the gradient projection method. Since the initial joint velocity is parameterized with the number of the redundancy, we only search the parameter value in the space of as many dimensions as the number of degrees of redundancy. We show through numerical examples that multiple nonhomotopic extremal solutions and the generality of the proposed method by considering the dynamics of a robot.

• 반도체디스플레이기술학회지
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• 제13권4호
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• pp.37-42
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• 2014

Stable running is a very important factor when we are building a control system. But, sometimes malfunction of the system controller is caused by several reasons. To solve these problems, some systems have prepared a backup controller. In the generality of cases, making a backup controller is no easy work. Especially, it becomes more difficult when many backup controllers have to be embodied in one system. In this paper, the multi-backup function controller which was implemented in the form of the network type distributed control system will be suggested. Also, using Arago Disk System that has a structure for inner loop control, the validity of the proposed methods will be verified.

• KDI Journal of Economic Policy
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• 제24권2호
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• pp.53-82
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• 2002

Earlier papers, regarding this topic, have shown that the optimal environmental tax rate under the second best situation typically smaller than that under the first best world, the well known Pigouvian tax. This paper casts a doubt on the generality of this result, since the conclusion was derived from the models which employed rather strict assumptions on the utility function, which is homothetic and separable. This paper, with simple-static CGE model, shows that the result of earlier studies is sensitive to the assumption on the utility function. According to the simulation results, as previous studies pointed out, if the utility function is assumed to be homothetic, the optimal environmental tax rate is smaller than the Pigouvian tax. In contrast, if certain type of non-homotheticity is allowed, the optimal environmental tax rate could be greater than the Pigouvian tax. The results of this simulation also imply that the enlargement of environmental tax base could enhance the efficiency of overall tax system. Hence, there will be a less burden to share for the tax authority from the policy change.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.338-341
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• 1994

This paper presents a Fuzzy-PID controller based on Fuzzy logic. Up to now PID controller has had the difficulty of obtaining the optimal gain, and Fuzzy controller has had the difficulty of determining scale factor affecting the performance of control. So that a Fuzzy-PID controller is presented here self tuning of the scale factor and optimal gain. The results of simulation show a good performance in comparison with Ziegler-Nichols controller, having the generality of determining the components of scale factor in Fuzzy rule.

• Tribology and Lubricants
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• 제4권2호
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• pp.28-35
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• 1988

A general and efficient algorithm is proposed for the analysis of the frictionless elastic contact problems. It utilizes a simplex-type algorithm with a modified entry rule and incoporates finite element method to obtain flexibility matrices. The algorithmic solution is compared with the Hertzian solution for the contact problem between two cylinders to prove its accuracy and the contact problem between pin and piston rod is solved and compared with the numerical results of Frankavilla and Zienkiewicz to demonstrate the generality and effectiveness of the suggested algorithm. The contact problem between mating involute gear teeth at the worst load position is considered. The computed contact stress is smaller than the result of Hertz's theory applied to the contact between two kinematically equivalent discs and the contact area is larger than that of Hertz's theory.