• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.115-119
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• 2001

The simulation of motion responses of a dolphin-moored ocean structure in shallow water when it cllides with a ship, has been carried out. The equation of motion in the time domain according to Cummin's theory is employed, and solved by making use of the Newmark-${\beta}$ method. The added mass and damping coefficients involved in the equations are abtained from a three-dimensional panel method in the frequency domain. The impact forces due to ship collision are calculated using both the elastic and non-elastic modelings. The mooring forces for dolphin systems of ocean structure are regarded as linear spring forces.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.3
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• pp.228-236
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• 1989

The theroy of variable structure control system (VSS) is applied to the position control for DC servo-motors. In order to use the microcomputer as a control device, the principles of VSS for the continuous-time system are extended to the discrete-time system. A new switching law is proposed to achieve the reduction of chattering. It adds a new switching structure to the conventional switching sturctures. This switching region is set near and including the conventional switching curve. The new algorithm is obtained for single-input second order system, and applied to the position control of a DC servo-motor. Experimental results show that the transient behavior is improved due to the reduction of chattering and good robustness properties are demonstrated.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.2
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• pp.326-340
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• 2017

This study explores the daily life of Korean designers in New York. We use in-depth interviews within the daily lives of participants to first reveal the time structure and meaning of everyday life. In this everyday time frame, this study reveals the content and meaning of life in New York, which is especially useful for fashion majors. Participants were 11 single Korean women around 30 years old working as designers in New York. Data was collected from Manhattan, New York, from November 2013 to February 2014 through the use of in-depth interviews and participant observation. Data collected daily life information on time usage, money, and energy that is first summarized into 229 meaning units. In the following, 55 central meanings were derived from stories common to behaviors for study participants and 19 subcategories were compressed into academic language. Finally, the generalized categories are divided into six categories of study life, work life, future life, family life, leisure life and fashion life. As a result of the first study, the daily time structure consisted of customary public time and personal repeat time. Second, the customary public time categories included the studying for 'Beginning to jump again to the best', 'Now working as a designer in New York', and future life expecting 'Future growing as a career woman'. Repeated personal time categories include family life: 'A single life of a lonely and poor gentile', leisure life: 'Healing life that is supported by abundant advanced culture', and fashion life: 'New York fashion life coexist with harmony'. Third, work was the center of everyday life for study participants versus fashion and leisure that were central to everyday life when not working.

• Journal of the Korea Society of Computer and Information
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• v.27 no.12
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• pp.209-217
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• 2022

Naval CMS(Combat Management System) is linked to various sensors and weapon equipment and use DDS(Data Distribution Service) for efficient data communication between ICU(Interface Control Unit) Node and IPN(Information Processing Node). In order to use DDS, software in the system communicates in an PUB/SUB(Publication/Subscribe) based on DDS topic. If the DDS messages structure in this PUB/SUB method does not match, problems such as incorrect command processing and wrong information delivery occur in sending and receiving application software. To improve this, this paper proposes a DDS message structure integrity verification method. To improve this, this paper proposes a DDS message structure integrity verification method using a hash tree. To verify the applicability of the proposed method to Naval CMS, the message integrity verification rate of the proposed method was measured, and the integrity verification method was applied to CMS and the initialization time of the existing combat management system was compared and the hash tree generation time of the message structures was measured to understand the effect on the operation and development process of CMS. Through this test, It was confirmed that the message structure verification method for system stability proposed in this paper can be applied to the Naval CMS.

• Journal of the Korean Society for Railway
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• v.11 no.1
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• pp.26-32
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• 2008

This paper discusses WBS (Work Breakdown Structure) that is known for technique of basic project management. The WBS use in domestic industries often exhibit errors in Its structure. The most common serious error is space-oriented breakdown structure of PBS (Product Breakdown Structure) that becomes the core element of the WBS. This paper proposes a method to correct the problem of space-oriented breakdown structure constructed in domestic railroad industry. DSM method was adopted to construct PBS containing function-oriented structure. The proposed process and method will contribute to minimize time that take to construct an accurate and useful PBS.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.131-142
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• 2001

Previous OD matrix estimation methods from link traffic counts have focused on the formulation of mathematical model and its solution algorithm. Thereby those methods have assumed that true or real OD is similar to the target OD and paid little attention to the properties of the change of OD structure. Although it is general situation that each OD pair increases or decreases due to significant land use and to large time variation between target OD with real OD, those methods have set unrealistic assumptions that target OD increases or decreases uniformly and that the OD structure does not change. Therefore those methods have showed poor performance of OD estimation in general situation. To cope with the problem. this paper suggests a new concept of OD matrix structure and shows the shortcomings of previous method′s dependancy on target OD matrix. We divide "OD trips" into "OD scale" and "OD structure". Where OD scale is a quantitative magnitude of OD trips and "OD structure" is ordinal OD scale. This paper use the same solution algorithm developed by Baek et al. (2000) for analysing the OD structure. Results of numerical examples show that the performance of the method is better than that of previous methods, while the previous methods have better performance in estimation only when OD trips increase or decrease. In addition to, if OD structure does not change, the results show that the error of estimation is low relatively regardless of the large difference of trips between target OD and real OD. This paper also shows that the model performance on OD structure and on OD trips is low as the number of origins that OD structure is changed increase. From the results we suggest that the change of OD structure can be more important information than the difference between target OD and real OD in OD estimation steps.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.403-406
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• 1999

Among the compression methods of moving picture information, a motion estimation method is used to remove time-repeating. The Block Matching Algorithm in motion estimation methods is the commonest one. In recent days, it is required the more advanced high quality in many image processing fields, for example HDTV, etc. Therefore, we have to accomplish not by means of Partial Search Algorithm, but by means of Full Search Algorithm in Block Matching Algorithm. In this paper, it is suggested a structure that reduce total calculation quantity and size, because the structure using Bit Plane select and use only 3bit of 8bit luminance signal.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.11
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• pp.1481-1488
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• 1995

Due to the low loss, broadband and accurate short time delay properties of optical fiber, it has attracted as a delay medium for high speed and broad-band signal processing. In this paper, we consider the coherent optical fiber filter of IIR lattice structure, which uses coherent light sources and consists of directional couplers whose coupling coefficients are restricted between 0 and 1. Considering restrictions of directional coupler, the design formulae and condition for realibility of optical fiber filter of IIR lattice structure which makes the optimal use of optical signal energy are derived.

• Proceedings of the Korean Statistical Society Conference
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• 2004.11a
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• pp.79-84
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• 2004

We use principal component analysis (PCA) to identify exons of a gene and further analyze their internal structures. The PCA is conducted on the short-time Fourier transform (STFT) based on the 64 codon sequences and the 4 nucleotide sequences. By comparing to independent component analysis (ICA), we can differentiate between the exon and intron regions, and how they are correlated in terms of the square magnitudes of STFTs. The experiment is done on the gene F56F11.4 in the chromosome III of C. elegans. For this data, the nucleotide based PCA identifies the exon and intron regions clearly. The codon based PCA reveals a weak internal structure in some exon regions, but not the others. The result of ICA shows that the nucleotides thymine (T) and guanine (G) have almost all the information of the exon and intron regions for this data. We hypothesize the existence of complex exon structures that deserve more detailed analysis.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1221-1223
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• 2003

With speediness of economy, the structure of land use has taken lots of change. How can we quickly and exactly obtain detailed land use/cover change information, and then we know land resource amount, quality, distributing and change direction. More and more high resolution satellite systems are under development. So we can make good use of RS data, existed GIS data and GPS data to extract change information and update map. In this paper a fully automated approach for detecting land use/cover change using remote sensing data with object-oriented classification based on GIS data, GPS data is presented (referring to Fig.1). At same time, I realize integrating raster with vector methods of updating the basic land use/land cover map based on 3S technology and this is becoming one of the most important developing direction in 3S application fields; land-use and cover change fields over the world. It has been successful applied in two tasks of The Ministry of Land and Resources P.R.C and taken some of benefit.