• Title/Summary/Keyword: first order line

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Damping Inter-area Low Frequency Oscillations in Large Power Systems with $H_{\infty}$ Control of TCSC PARTI : TCSC Siting (TCSC의 $H_{\infty}$ 제어에 의한 대규모 전력계통의 지역간 저주파진동 억제 PartI : 설치지점 선정)

  • Kim, Yong-Gu;Sim, Gwan-Sik;Song, Seong-Geun;Kim, Yeong-Hwan;Nam, Hae-Gon
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.49 no.5
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    • pp.226-232
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    • 2000
  • This paper presents application results of the augmented matrix eigen-sensitivity theories to TCSC siting problem for damping the inter-area low frequency oscillation in the large KEPCO system. First and second-order eigen-sensitivities of the inter-area low frequency oscillation in the large KEPCO system. First and second-order eigen-sensitivities of the inter-area mode are computed fro changes in susceptance of the transmission lines. The lines having high sensitivity are chosen as the initial candidates for installing TCSC. Then for each of the chosen candidates, Bodeplot of the transfer function with line susceptance as the input and the bus voltage at one side of the line as the output is computed. Using the Bode plots, the lines having any zeros near the inter-area mode are screened out since design of TCSC controller is very difficult in such a case. The $H_{\infty}$ TCSC controller installed at any finally chosen candidate is found to be effective in damping the inter-area oscillation, and the proposed TCSC siting algorithm is proved to be valid. Design of $H_{\infty}$ controller is described in Part IIof this paper.

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Development of Shoes' Easy-Order Prototype According to Foot Types of Juveniles In On-Line 3D Virtual Reality (청소년의 발의 형태 분류에 따른 On-line 3D 가상현실에서의 신발류 이지오더 Prototype 개발)

  • Choi, Sung-Won;Lim, Ji-Young
    • The Journal of the Korea Contents Association
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    • v.6 no.11
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    • pp.182-189
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    • 2006
  • Consumers can choose suitable shoes for their feet in off-line shopping. However, in on-line shopping, because they can not wear shoes, compare to the off-line shopping, there are many problems in internet shopping. And the solution of user-oriented internet shopping is development of new type of prototype which is accessible to user and to offer visual information through 3D-virtual reality. We made this Prototype that the consumer can measure their own shoes size. And the consumer can print out their foot size in the internet database and measure their own foot size and type. And we maximized the visual experience though it is indirect and then we wanted to overcome a emotional experience in the real world. we visualized first, 'the softness' of shoes meterial, second 'the drainage' in the realtion of shoes meterial and water, third 'the close adhesion' in the realtion of shoes and consumer's their own foot and last 'the elasticity' in the relation of the shoes outer sole and surface. The result of this research can solve the problem in the existing on-line shoes' shop and it will become an alternative plan. And this prototype just will not become the localization at the on-line shoes' shop. In true sense, it will be an important example in the whole internet industry.

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An Empirical Study on costing and Pricing in On-Line Database Service (온라인 데이터베이스 서비스의 원가계산과 가격결정에 관한 실증적 연구)

  • Lee, Yeong-Jae;Jeong, U-Seong
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.1
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    • pp.23-38
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    • 1997
  • Based on previous research for end-users information needs, this research is to investigate DB costing method for decision-making on pricing of DB service by critical factors. The first phase of the research classifies the elements of DB product cost accounting by activities of the circulation system of information in DB service. The second phase is to develop model based on results of DB product costing in the first phase of research. The third phase of research is to present the process of DB product cost accounting by applying the model to an on-line service company. Finally, the research develops the pricing decision model to determine the priority of each factor by survey from major on-line service companies in America and Japan. It is essential to research further regarding the DB product costing and pricing methods in order to determine a proper DB service charge. The right Pricing decision in the DB service charge will contribute to the growth of the DB industry.

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ACCURACY ASSESSMENT BY REFINING THE RATIONAL POLYNOMIALS COEFFICIENTS(RPCs) OF IKONOS IMAGERY

  • LEE SEUNG-CHAN;JUNG HYUNG-SUP;WON JOONG-SUN
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.344-346
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    • 2004
  • IKONOS 1m satellite imagery is particularly well suited for 3-D feature extraction and 1 :5,000 scale topographic mapping. Because the image line and sample calculated by given RPCs have the error of more than 11m, in order to be able to perform feature extraction and topographic mapping, rational polynomial coefficients(RPCs) camera model that are derived from the very complex IKONOS sensor model to describe the object-image geometry must be refined by several Ground Control Points(GCPs). This paper presents a quantitative evaluation of the geometric accuracy that can be achieved with IKONOS imagery by refining the offset and scaling factors of RPCs using several GCPs. If only two GCPs are available, the offsets and scale factors of image line and sample are updated. If we have more than three GCPs, four parameters of the offsets and scale factors of image line and sample are refined first, and then six parameters of the offsets and scale factors of latitude, longitude and height are updated. The stereo images acquired by IKONOS satellite are tested using six ground points. First, the RPCs model was refined using 2 GCPs and 4 check points acquired by GPS. The results from IKONOS stereo images are reported and these show that the RMSE of check point acquired from left images and right are 1.021m and 1.447m. And then we update the RPCs model using 4 GCPs and 2 check points. The RMSE of geometric accuracy is 0.621 m in left image and 0.816m in right image.

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A Study on the Frequency Scaling Methods Using LSP Parameters Distribution Characteristics (LSP 파라미터 분포특성을 이용한 주파수대역 조절법에 관한 연구)

  • 민소연;배명진
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.3
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    • pp.304-309
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    • 2002
  • We propose the computation reduction method of real root method that is mainly used in the CELP (Code Excited Linear Prediction) vocoder. The real root method is that if polynomial equations have the real roots, we are able to find those and transform them into LSP. However, this method takes much time to compute, because the root searching is processed sequentially in frequency region. In this paper, to reduce the computation time of real root, we compare the real root method with two methods. In first method, we use the mal scale of searching frequency region that is linear below 1 kHz and logarithmic above. In second method, The searching frequency region and searching interval are ordered by each coefficient's distribution. In order to compare real root method with proposed methods, we measured the following two. First, we compared the position of transformed LSP (Line Spectrum Pairs) parameters in the proposed methods with these of real root method. Second, we measured how long computation time is reduced. The experimental results of both methods that the searching time was reduced by about 47% in average without the change of LSP parameters.

Cognitive Processing Therapy as a First-line Treatment for Post-Traumatic Stress Disorder (인지처리치료: 외상후 스트레스 장애의 일차 치료)

  • Jin-Hee, Choi;Hyung-Seok, So;Soonjo, Hwang;Ji-Woo, Suk;Hayun, Choi;Seung-Hoon, Lee;EunYoung, Lee
    • Korean Journal of Psychosomatic Medicine
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    • v.30 no.2
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    • pp.80-98
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    • 2022
  • Posttraumatic stress disorder (PTSD) is well known to have a limited response to drug treatment. Many recently published clinical care guidelines recommend trauma-focused psychotherapies such as cognitive processing therapy (CPT) and prolonged exposure therapy (PE) as first-line treatment and medication such as serotonin reuptake inhibitors and venlafaxine as second-line treatment. Current review introduces the session composition and contents of CPT and presents various CPT studies that show therapeutic effect for civilian and veterans/military with PTSD. In order for clinicians to help effectively patients with PTSD, it is necessary to learn and actively use evidence-based trauma-focused psychotherapies including CPT and PE.

Design of ZOR antenna for 2.45GHz WLAN using CRLH-TL (CRLH-TL을 이용한 2.45GHz 무선랜용 ZOR 안테나 설계)

  • Kim, Seung-Hwan;Yu, Jin-Ha;Lee, Young-Soon
    • Journal of Advanced Navigation Technology
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    • v.16 no.5
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    • pp.773-780
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    • 2012
  • ZOR(zeroth order resonance) antenna for 2.45GHz WLAN(wireless local area network) is designed by use of CRLH-TL(composite right left handed transmission line) meta-material. The electrical length of conventional antennas is determined generally according to the resonant frequency, whereas that of ZOR antenna can be determined without reference to the resonant frequency. Therefore ZOR antenna has advantage in miniaturization of antenna in comparison with conventional antennas. In order to design such ZOR antenna, first unit cell with electrical length shorter than a quarter wavelength at 2.45GHz is designed to the some characteristics of homogeneous medium. In order to decrease resonant frequency and enhance frequency bandwidth, the proposed antenna is fed by CPW(co-planar waveguide) and short stub between radiation patch and ground plane is used for obtaining both higher inductance and smaller capacitance than previous mush-room type of CRLH-TL.

The MPEG-7 based Video Database (MPEG-7에 기반한 동영상 데이터베이스)

  • Lee, Soon-Hee
    • Journal of the Korea Computer Industry Society
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    • v.8 no.2
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    • pp.103-106
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    • 2007
  • In order to construct a Video Database, shot change detection should be made first. But, because these processes are not automated perfectly, we need a lot of time and efforts now. And, there are many shot change detection algorithms, which can't always insure the perfect result because of the editing effects such as cut, wipe, and dissolves used in film production. Therefore, in order to receive the exact shot change, It needs the verification and correction by manual processing at any cost. Spatiotemporal slice is a simple image condensing method for the content changes of video. The editing effects are expressed on the Spatiotemporal slice in the visually noticed form of vertical line, diagonal line, curved line and gradual color changes, etc. Accordingly the parts doubted as a shot change can be easily detected by the change of the Spatiotemporal slice without replaying the video. The system proposed in this study makes it possible to delete the false detected key frames, and create the undetected key frames on the Spatiotemporal slice.

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A study of the train traffic optimal control system in a circular metro line (도시형 순환 열차에서 운전 최적제어 시스템에 관한 연구)

  • Hong, Hyo-Sik;Ryu, Kwang-Gyun;Song, Noon-Suck
    • Proceedings of the KSR Conference
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    • 2003.10c
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    • pp.236-246
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    • 2003
  • This paper is implemented a control algorithm in order to be stable and minimized to entire train traffic system at delayed case. Signal ing system is described wi th algebraic equations given for train headway, Discrete-event simulation principles are reviewed and a demonstration block signaling model using the technique is implemented. Train congestion at station entrance for short headway operation is demonstrated and the propagation of delays along a platform of trains from any imposed delay to the leading train is also shown. A rail way signaling system is by nature a distributed operation with event triggered at discrete intervals. Although the train kinematic variables of position, velocity, and acceleration are continually changing, the changes are triggered when the trains pass over section boundaries and arrive at signals and route switches. This paper deals with linear-mode1ing, stability and optimal control for the traffic on such metro line of the model is reconstructed in order to adapt the circuits. This paper propose optimal control laws wi th state feedback ensuring the stability of the modeled system for circuits. Simulation results show the benefit to be expected from an efficient traffic control. The main results are summarized as follows: 1. In this paper we develop a linear model describing the traffic for both loop lines, two state space equations have been analyzed. The first one is adapted to the situation where a complete nominal time schedule is available while second one is adapted when only the nominal time interval between trains is known, in both cases we show the unstability of the traffic when the proceeding train is delayed following properties, - They are easily implemented at law cost on existing lines. - They ensure the exponetial stability of loop system. 2. These control laws have been tested on a traffic simulation software taking into the non-linearites and the physical constraints on a metro line. By means of simulation, the efficiency of the proposed optimal control laws are shown.

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Morphological Studies on the Jack Mackerel Populations

  • Kim, Wan Soo
    • 한국해양학회지
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    • v.4 no.1
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    • pp.17-35
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    • 1969
  • This work concerns morphological studies of the Japaness jack mackerel, Trachurus japonicus(Temminck & Schlegel). A total of 48 random samples consisting of 2669 fish is examined, representing three geographic regions, namely, Kamakura, Nagasaki, and Tottori. Preservation affects length and weight of fish considerably, but the variability after 10 days is shown to be negligible. The variability in measuring the morphometric characters due to different measures and orders is found to be significant. They are relatively small, however, compared to the variability in mean length to be expected in samples drawn from the population. Two meristic characters, namely, anal and second dorsal fin rays and three morphometric characters, namely, head length, first and second dorsal insertion distances are chosen for the study. Results of the statistical analysis reveal that differences in the selected meristic characters among samples within and between regions are found to be significant. In general, it is reasonable to state that the jack mackerel collected in Nagasaki region, on the average, have greatest number of anal fin ray and second dorsal fin ray followed by Kamakura, and Tottori regions in that order. It is found that although no significant differences in the slope of regression line are noticed, the mean differences of the selected morphometric measurements in relation to fish length are found to be significant among samples within each region. Differences in the regression coefficients as well as the adjusted sample means are found to be significant between regions. The analysis suggests that samples from Nagasaki region, on the average, have longest head length and greatest distances from snout to the insertion of first dorsal and second dorsal fins followed by Kamakura, and Tottori regions in that order.

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