• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.12
• /
• pp.2292-2297
• /
• 2010

To improve the performances of Sawyer motors and to regulate yaw rotation, various feedback control methods have been developed. Almost all of these methods require information on the position, velocity or full state of the motor. Therefore, in this paper, a nonlinear observer is designed to estimate the full state of the four forcers in a Sawyer motor. The proposed method estimates the full state using only positional feedback. Generally, Sawyer motors are operated within a yaw magnitude of several degrees; outside of this range, Sawyer motors step out. Therefore, this observer design assumes that the yaw is within ${\pm}90^\b{o}$. The convergence of the estimation error is proven using the Lyapunov method. The proposed observer guarantees that the estimation error globally exponentially converges to zero for all arbitrary initial conditions. Furthermore, since the proposed observer does not require any transformation, it may result in a reduction in the commutation delay. The simulation results show the performance of the proposed observer.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.50
• /
• pp.61-85
• /
• 2011

The agreement to arbitrate is a central feature of commercial arbitration and the lack of a valid arbitration agreement is recognised as a reason why any arbitral award may not be recognized as binding by the courts or may be set aside. The purpose of this paper is to clarify the China's present arbitration law and practice in respect of determination of the validity of international commercial arbitration agreement. Most arbitration laws only require an arbitration agreement to be "in writing". But the arbitration law of the China require an arbitration agreement shall contain the following: 1. The expression of application for arbitration. 2. Matters for arbitration. 3. The arbitration commission chosen. And China's present arbitration law and practice in respect of determination of the validity of international commercial arbitration agreement are somewhat different from the other nations.

• Journal of Astronomy and Space Sciences
• /
• v.31 no.3
• /
• pp.205-214
• /
• 2014

In this study, a star identification algorithm which utilizes pivot patterns instead of apparent magnitude information was developed. The new star identification algorithm consists of two steps of recognition process. In the first step, the brightest star in a sensor image is identified using the orientation of brightness between two stars as recognition information. In the second step, cell indexes are used as new recognition information to identify dimmer stars, which are derived from the brightest star already identified. If we use the cell index information, we can search over limited portion of the star catalogue database, which enables the faster identification of dimmer stars. The new pivot algorithm does not require calibrations on the apparent magnitude of a star but it shows robust characteristics on the errors of apparent magnitude compared to conventional pivot algorithms which require the apparent magnitude information.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.2 no.1
• /
• pp.23-33
• /
• 1984

Color providing compounds on image transfer process in color photo graphy was studied with polaroid and Kodak products as a model. These compounds was inititally alkali-mobile or alkali-immobile. Alkali-mobile compunds require imagewise immobilifation in the process or alkali immoble compounds require mobilization by the cleavage reaction. As a result of studies, the polaroid products was showed alkali mobile and Kodak product represented alkali immobile.

• Transactions of The Korea Fluid Power Systems Society
• /
• v.4 no.4
• /
• pp.8-14
• /
• 2007

The electro-hydraulic pump is usually used in testing equipments which require one control function. But until now, it is not applied to industrial equipments which are exposed to severe working environment and require various control functions. This paper proposes a technique which controls continuously flow, pressure and power by utilizing switching control mode. Mathematical model is developed from the continuity equation for the pressurized control volume and the torque balance for the swash plate motion. To simplify the model we make the linear state equation by differentiating the nonlinear model. We analyze the stability and disturbance by using the state variable model. Finally, we review the control performances of flow, pressure and power by tests using PID controller.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.3 no.1
• /
• pp.66-75
• /
• 2000

The purpose of this study is to develop and illustrate methods of applying trade-off techniques to landing craft air cushion design evaluation. The problem areas of concern are the application of quantitative analytical methods to conceptual design. The interrelationships between composite system measures and selected performance requirements(speed, cruising range, cargo etc.) are analyzed and the expressions for gross weight are developed as functions of performance parameters. Trade-offs of performance parameters in terms of weight are then calculated. The application of these results to evaluation of Require Operational Capabilities are illustrated.

• Korean Journal of Child Studies
• /
• v.13 no.2
• /
• pp.33-51
• /
• 1992

The purpose of this study was to investigate activities of kindergarteners in the mathematics corner. The study included an analysis of children's interactions with mathematics materials and of children's peer interactions during mathematics activities. The subjects were 47 children aged three to four and 72 children aged four to five from four classes of two kindergartens in Kwangju. Children's math activities during free play sessions were observed and audiotaped. The data were coded by the categories of children's peer interactions and types of mathematics manipulations. The characteristics of children's peer interactions and materials frequently selected by the subjects were identified. The results indicated that (1) most of the math materials were for passive manipulation that require children to respond according to predetermined conditions like the rules of games, but (2) the materials that children liked to play with were active manipulative materials that require diversity and flexibility of children's thinking and allow several choices for solutions, and (3) children's peer interactions during math activities were categorized into unilateral and reciprocal/collaborative peer interaction type.

• Journal of the Korean Institute of Oriental Medical Informatics
• /
• v.11 no.1
• /
• pp.74-82
• /
• 2005

Objective We wish that oriental medicine theses can now be searched for by computer. So we have studied thesaurus and keywords in OMIS(Oriental Medicine Information System) Methodologies We have compared the keyword with the Thesaurus in the OMIS. So We have analyzed those into the agreement rate and the disagreement rate. Repeatedly, we have analyzed the agreement rate and the disagreement rate in chronological order. Conclusions 1. As the most of authors don't know about thesaurus, So many keywords disagree with thesaurus. 2. Because thesaurus system is very difficult to general authors. So system administors must build synonym data base, if many authors easily use thesaurus system. 3. We have to require institute editor to modify editorial policy. Presently most of institute require only one foreign language keywords, but it must be required foreign and Korean language keywords. 4. We must study not only oriental medicine thesaurus but also the other science thesaurus.

• Journal of the Korean housing association
• /
• v.12 no.2
• /
• pp.25-34
• /
• 2001

In this study, the shared facilities and space in the multi-family housing which residents could maintain contacts with their neighbors were investigated and analyzed. It could find the shared facilities and space so that residents could maintain to contact with their neighbors after surveying the dwellers requirements. Also it could specify the importance of the neighborhood common spaces and the conditions for the planning of the shared facilities. Analyzing residents requirement of set-up location, this study lead to the following suggestions concerning the facilities design: In the first neighborhood-circle, it require to be related the household affairs of housewives on the adjacent space to a dwelling-unit. In the second neighborhood-circle, it require especially the facilities for children play, study, reading, hobby etc. These facilities need establish each 4-5 floor in high-rise building estates. The roof & underground floors has been recognized in important & essential place for living facilities. Therefore, it is needed to improve to get ready to receive the various facilities.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.1
• /
• pp.214-218
• /
• 2016

Catenary maintains the tension of the catenary using automatic tensioning devices to meet performance require m ents exhibited by the house is generated in accordance with the new external temperature changes. Double spring type autom a tic tensioning device is permanent and does not require the usual maintenance, and a deterioration due to no recognizable ab normalities characteristic of the nature of the internal state has the disadvantage that can not be confirmed. The disassembled for automatic spring-tension capabilities ensure efficient operation and life expectancy of the adjustment device via a check by analyzing the changes in old age determine the remaining lifetime is expected to be available as a basis for maintenance in the future.