• Journal of Electrical Engineering and Technology
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• 제2권2호
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• pp.172-177
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• 2007

Wavelet transforms provide basis functions for time-frequency analysis and have properties that are particularly useful for the compression of analogue point on wave transient and disturbance power system signals. This paper evaluates the compression properties of the discrete wavelet transform using actual power system data. The results presented in the paper indicate that reduction ratios up to 10:1 with acceptable distortion are achievable. The paper discusses the application of the reduction method for expedient fault analysis and protection assessment.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2446-2450
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• 2013

Oxindole dimers have been used as intermediates in the synthesis of various cyclotryptamine alkaloids. An efficient direct synthesis of oxindole dimers has been carried out from 3-substituted oxindoles via an oxidative dimerization using manganese(III) acetate or copper acetate/silver acetate system.

• 소음진동
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• 제10권2호
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• pp.325-330
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• 2000

A dynamic absorber is used to protect the primary vibration system under the steady-state harmonic disturbance. In a number of cases it appears expedient to install several absorbers of smaller masses instead of one. This may be due to the need of distribute the absorber's response along the construction, restrictions on the absorber's installation. So, we studied characteristics of the primary vibration system for the optimal natural frequency ratio and the optimal damping ratio of serial multi-dynamic absorber. Also we obtained the optimum values of the serial multi-dynamic absorber parameters using computer simulation for the damped primary vibration system. In designing multi-dynamic absorber, we presented for the optimal natural frequency and the optimal damping ratio of multi-dynamic absorbers.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.1063-1070
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• 2005

Number of subway train units that Seoul Metropolitan Subway Corporation as at September 2005 is 1.944 on 4 routes from 60 units at the time of commencement of operation, having grown exponentially. Along with increase in the number of passengers the role of subway as safer and expedient means of transportation is now being required. Furthermore, the Corporation has been researching on means of improving the safety and reliability of subway entry/exit doors which has become an essential task and directly effect the safety of the passengers. In this Study, has developed sensory control system for the entry/exit door of the subway train using non-contact proximity sensor as a part of review of and measures against various issues of entry/exit door of the subway trains currently under operation. In addition, this sensor system was verified through test production and tests. If this technology becomes commercialized and practically utilized in the future, it would be able to make definite contribution to the safer transportation of passengers.

• 한국의류산업학회지
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• 제7권2호
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• pp.196-202
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• 2005

The purposes of this study were to investigate and analyze the relationship between the elements of textile design and consumer emotion and to suggest effective design methods. In addition, the forecasting system for textile design based on the results of this study was developed. The database system of textile design was organized by installing Mysql database server and tomcat servlet container on windows NT. The user interface was utilized using jsp on the web. This study findings can provide textile design samples which were suitable for each emotional factor, and an evaluation basis for each design element by the descriptive system of textile design. The forecasting system based on this study findings can also provide specific design methods for the effectiveness of consumer emotion and can be applied in a practical design process. This study based on the results of the quantitative analysis on consumer emotion has presented an objective and an efficient design method. This will be a useful expedient to improve the existing textile design process and for the consumer design.

• 한국멀티미디어학회논문지
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• 제5권2호
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• pp.129-140
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• 2002

XML은 웹 상에서 문서 데이터 교환을 위한 표준이 되었다. 현재 대부분의 상업적인 데이터가 관계형 데이터베이스 시스템에 저장되어 있다. 관계형 데이터베이스에 저장되어 있는 문서를B2B간에 교환하기 위해서는 XML형태의 문서로 변환하는 작업이 필요하다. 본 논문에서는 관계형 데이터베이스에 저장되어 있는 문서데이터로부터 필요한 정보를 쉽고 편리하게 질의하고 결과를 얻을 수 있도록 XML질의처리시스템에 대한 연구를 하였다. 그리고 XML 문서를 사용하는 사용자들이 관계형 데이터 베이스에 저장되어 있는 문서를 XML문서로 간주하여 질의할 수 있도록 하기 위해서 R2X라 부르는 XML뷰를 설계하였다. 본 논문에서는 이 R2X뷰를 이용하여 XQL질의언어로 편리하게 질의할 수 있는 질의처리 시스템을 설계 및 구현하였다.

• 한국정밀공학회지
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• 제17권3호
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• pp.47-57
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• 2000

In this study, PC-based dicing machine and driving software were constructed for the purpose of automation of wafer cutting process. To automate the machine, hard automation including vision, loading, and software were considered in the development. Auto loading device and vision system were adopted for the increase of productivity, GUI software programmed for the expedient operation. The dicing machine is operated by the control algorithm and some parameters. It is verified that this kind of PC based automation has a great potential compared with the conventional dicing machine when applied to manufacturing some kinds of wafers as a test purpose.

• Advances in nano research
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• 제5권1호
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• pp.13-25
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• 2017

We examine the total optical dielectric function (TODF) of impurity doped GaAs quantum dot (QD) from the viewpoint of anisotropy, position-dependent effective mass (PDEM) and position dependent dielectric screening function (PDDSF), both in presence and absence of noise. The dopant impurity potential is Gaussian in nature and noise employed is Gaussian white noise that has been applied to the doped system via two different modes; additive and multiplicative. A change from fixed effective mass and fixed dielectric constant to those which depend on the dopant coordinate manifestly affects TODF. Presence of noise and also its mode of application bring about more rich subtlety in the observed TODF profiles. The findings indicate promising scope of harnessing the TODF of doped QD systems through expedient control of site of dopant incorporation and application of noise in desired mode.

• 한국항해학회지
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• 제18권2호
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• pp.57-67
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• 1994

This paper treats the optimization analysis of tactical ship scheduling problems in the world seaborne bulk trade. The authors use the term 'tactial' to describe the ship scheduling problem where the owners should employ skillful tactics as an expedient toward gaining the higher profits per period in short term. Relevent research and related problems on ship scheduling problems are reviewed briefly and a model for the tactical ship scheduling problem formulated as Set Problem is introduced by modifying the previous work of Fisher(1989). The reality and practicability of the model is validated by some ship-ping statistics. Proper solution approaches are outlined in the context of computational tractability in tackling the Mixed Integer Propramming. Some underlying consideration for the computational experiment is also mentioned. The authors conclude the paper with the remarks on the need of user-friendly Decision Support System for ship scheduling under varying decision environment.

• 대한전기학회논문지
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• 제33권11호
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• pp.456-463
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• 1984

The fast-rising high-voltage pulse generation circuit system of a theta pinch is both theoretically and experimentally investigated. The idealized model of this circuit system is a hybrid circuit system composed of three parts: a lumped circuit part being consisted of a capacitor bank and a spark switch connected in series, another lumped circuit part being consisted of the Blumlein transmission line, whose end load is the pinch coil. the voltage difference between two ends of the pinch coil is formulated by analyzing this hybrid circuit system by means of the law of the signal propagation in the transmission line and Kirchhoff's laws. The expedient numerical method for computer calculation is developed to generate the pulse profile of the voltage difference across the pinch coil. The period of the experimentally measured main pulse is a fourth of the theoretical one neglecting the resistance of the pinch coil. We attribute this discrepancy to the modelling in the theoretical calculation that hte resistance and inductance of the spark switch and capacitor bank are assumed to be constant through discharge. Therefore, we can see that the rise time of the imploding magnetic-field pulse is mainly dependent on the spark switch and capacitor bank.