• Title/Summary/Keyword: Phase Calculator

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A Comparative Study of Branch Metric Calculator in QAM-TCM Decoder (QAM-TCM 복호기의 가지척도계산방식 비교 연구)

  • 김진우;최시연;강병희;오길남;김덕현
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.249-252
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    • 2001
  • TCM(Trellis Coded Modulation) has soft decision scheme so that BM(Branch Metric) calculates the ED(Euclidean Distance) between the received signal and each code words in signal space. For computing the ED, square and square root computations increase the hardware complexity. Some simplified method is known for convolutional codes with QPSK(Quadrature Phase Shift Keying), PSK(Phase Shift Keying) modulation. But it is not acceptable for QAM (Quadrature Amplitude Modulation)-TCM scheme. In this paper, we suggest that two modified BM computation methods, which is applicable for QAM-TCM. By comparative study, we also assessed two proposed method in the case of hardware complexity and BER (Bit Error Rate) performance.

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Implementation of Inverter Systems for DC Power Regeneration

  • Kim Kyung-Won;Yoon In-Sic;Seo Young-Min;Hong Soon-Chan;Yoon Duck-Yong
    • Proceedings of the KIPE Conference
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    • 2001.10a
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    • pp.126-131
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    • 2001
  • This paper deals with implementation of inverter systems for DC power regeneration, which can regenerate the excessive DC power from DC bus line to AC supply in substations for traction systems. From the viewpoint of both power capacity and switching losses, a three-phase square-wave inverter system is adopted. To control the regenerated power, the magnitude and phase of fundamental output voltages should be appropriately controlled in spite of the variation of input DC voltage. Inverters are operated with modified a-conduction mode to fix the potential of each arm. The overall system consists of the line-to-line voltage and line current sensors, an actual power calculator using d-q transformation method, a complex power controller with PI control scheme, a gating signal generator for modified $\alpha-conduction\;mode\;with\;\delta\;and\;\alpha$, a DPLL for frequency followup, and power circuit.

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A Simple Interactive 3D Interior Design Application for Living Room - Cost Management

  • Winnie, Chin;Hui, Saw Seow;Gee, Yap Seok
    • Journal of Multimedia Information System
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    • v.4 no.3
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    • pp.157-162
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    • 2017
  • The title of this project is "A Simple Interactive 3D Interior Design Application for Living Room - Cost Management", focusing on developing an application that enables costing and designing to be executed concurrently in interior design phases. This is because any changes made at costing phase after design phase is completed, it will potentially lead to unnecessary increase in cost and time. Therefore, the objective of this project is aimed to devise a cost management module to be included in the proposed application, allowing interior designer to make cost-based decision at the designing phase itself. This can be achieved through its proposed functions which include total cost update, budget management, cost estimator calculator and material list generation. The methodology being proposed in this project is Prototyping Development, categorized under Rapid Application Development (RAD), by starting off with planning, analysis, design and implementation phases are performed concurrently and repeatedly in a cycle to produce a prototype until the application is completed. In the end of this project, the developed prototype is expected to contribute a better solution towards cost management in interior design.

Three-Phase Line-Interactive Dynamic Voltage Restorer with a New Sag Detection Algorithm

  • Jeong, Jong-Kyou;Lee, Ji-Heon;Han, Byung-Moon
    • Journal of Power Electronics
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    • v.10 no.2
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    • pp.203-209
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    • 2010
  • This paper describes the development of a three-phase line-interactive DVR with a new sag detection algorithm. The developed detection algorithm has a hybrid structure composed of an instantaneous detector and RMS-variation detectors. The source voltage passes through the sliding-window DFT and RMS calculator, and the instantaneous sag detector. If an instantaneous sag is detected, the RMS variation detector-1 is selected to calculate the RMS variation. The RMS variation detector-2 is selected when the instantaneous sag occurs under the operation of the RMS variation detector-1. The feasibility of the proposed algorithm is verified through computer simulations and experimental work with a prototype of a line-interactive DVR with a 3kVA rating. The line-interactive DVR with the proposed algorithm can compensate for an input voltage sag or an interruption within a 2ms delay. The developed DVR can effectively compensate for a voltage sag or interruption in sensitive loads, such as computers, communications equipment, and automation equipment.

A Study of the Changes of Breast Uptake in Menstrual Cycle on 18F-FDG PET/CT (월경 주기에 따른 18F-FDG PET/CT에서 유방 섭취 변화에 관한 고찰)

  • Tak, Yeojin;Park, Min Soo;Lee, Juyoung;Park, Hoon-Hee
    • Journal of radiological science and technology
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    • v.38 no.1
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    • pp.31-38
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    • 2015
  • $^{18}F-FDG$ PET/CT has been known a useful modality to diagnose high-glucose-using cells such as cancer cells by glucose metabolism of FDG. Mainly, FDG takes on cancer and inflammatory cells; however, there have been FDG uptakes on normal tissues by individual physiological characteristics, occasionally. Especially, in fertile females, unusual FDG uptake of breast changes as the menstrual cycle, and disturb diagnosis. Therefore, the study aimed to evaluate the change of breast FDG uptake in menstrual cycle on $^{18}F-FDG$ PET/CT. 160 females ($34{\pm}3.5$ years old) who do not undergo a gynecologic anamnesis and have regular menstrual cycle over the previous 6 months were examined. They were divided 4 groups (each 40 patients) as flow phase, proliferative phase, ovulatory phase and secretory phase using Pregnancy Calculator 0.14. and history taking. Discovery Ste (GE Healthcare, Milwaukee, Mi, USA) was used a s PET/CT. We analyzed SUVs on accumulated region on breast, and 3 nuclear medicine specialists did the Blind test. SUVs on the Breast were flow phase ($1.64{\pm}0.25$), proliferative phase ($0.93{\pm}0.28$), ovulatory phase ($1.66{\pm}0.26$) and secretory phase ($1.77{\pm}0.28$). It showed high uptake value in secretory, flow phase and ovulatory phase (p<0.05). In gross analysis, the accumulation of breast was divided into 3 grades as comparing with lung and liver. The breast's uptake was equal to lung (Grade I); between lung and liver (Grade II); equal to or greater than liver (Grade III). The results showed high uptake value in secretory, flow phase and ovulatory phase (p<0.05). In fertile females, FDG uptake of breast changed as menstrual cycle, and it available to diagnose breast disease. Therefore, we consider reducing false-negative finding of breast disease, by doing examination on appropriate period through history taking about individual menstrual cycle.

A Study of the Change of Breast Uptake in Menstrual Cycle on $^{18}F$-FDG PET/CT (월경 주기에 따른 $^{18}F$-FDG PET/CT에서의 유방 섭취 변화에 관한 고찰)

  • Park, Min-Soo;Park, Hoon-Hee;Kim, Jung-Yul;Lim, Han-Sang;Kim, Jae-Sam;Lee, Chang-Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.39-44
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    • 2011
  • Purpose: $^{18}F$-FDG PET/CT has been known a useful modality to diagnose high-glucose-using cells such as cancer cells by glucose metabolism of FDG. Mainly, FDG takes on cancer and inflammatory cells; However, There have been FDG uptakes on normal tissues by individual physiological characteristics, occasionally. Especially, in fertile females, unusual FDG uptake of breast changes as the menstrual cycle, and disturb diagnosis. Therefore, the study aimed to evaluate the change of breast FDG uptake in menstrual cycle on $^{18}F$-FDG PET/CT. Materials and Methods: 160 females ($34{\pm}3.5$ years old) who do not undergo a gynecologic anamnesis and have regular menstrual cycle over the previous 6 months were examined, from March 2009 to February 2010. They were divided 4 groups (each 40 patients) as flow phase, proliferative phase, ovulatory phase and secretory phase using Pregnancy Calculator 0.14. and history taking. Discovery Ste (GE Healthcare, Milwaukee, Mi, USA) was used as PET/CT. We analyzed SUVs on accumulated region on breast, and 3 nuclear medicine specialists did the Blind test. Results: SUVs on the Breast were flow phase ($1.64{\pm}0.25$), proliferative phase ($0.93{\pm}0.28$), ovulatory phase ($1.66{\pm}0.26$) and secretory phase ($1.77{\pm}0.28$). It showed high uptake value in secretory, flow phase and ovulatory phase (p<0.05). In gross analysis, the accumulation of breast was divided into 3 grades as comparing with lung and liver. The breast's uptake was equal to lung (Grade I); between lung and liver (Grade II); equal to or greater than liver (Grade III). The results showed high uptake value in secretory, flow phase and ovulatory phase (p<0.05). Conclusion: In fertile females, FDG uptake of breast changed as menstrual cycle, and it available to diagnose breast disease. Therefore, we consider reducing false-negative finding of breast disease, by doing examination on appropriate period through history taking about individual menstrual cycle.

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Robust PLL Algorithms for Grid Voltage with DC Offset voltages (옵셋오차전압이 포함된 계통 전압에 강인한 PLL 알고리즘)

  • Lee, C.R.;Chun, T.W.;Lee, H.H.;Kim, H.G.;Nho, E.C.
    • Proceedings of the KIPE Conference
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    • 2016.07a
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    • pp.327-328
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    • 2016
  • This paper proposes the PLL algorithms with both the quadrature signal generator (QSG) and the positive-sequence calculator (PSC) in order to remove the effects of the three-phase grid voltage with dc offset voltages. The performances of the proposed method are verified with both the simulation result and the experimental result with 32-bit DSP.

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A Study on Computerization of the Sight Reduction(I) (천측계산의 전산화에 관한 연구(I))

  • 윤여정
    • Journal of the Korean Institute of Navigation
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    • v.8 no.2
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    • pp.1-13
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    • 1984
  • This paper concerns computerization of the altitude correction in the sight reduction process. To obtain observed altitude, the factors such as refraction, parallx, semidiameter, phase etc, are corrected to sextant altitude. The factors are the arguments into the nautical almanac table from which are extracted values to add to or substract from the raw sight to obtain corrected value. If the altitude correction is to be done by sophisticated calculator, each factors must be formulated. The author studies the formulation of above factors, and simply from the date and ephemeris time of the sighting calculate the values of the factors. The calculated values are compared with that from nautical almanac, and it is confirmed that the formulae are practically used.

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GIS Application Model for Spatial Simulation of Surface Runoff from a Small Watershed(I) (소유역 지표유출의 공간적 해석을 위한 지리정보시스템의 응용모형(I) -격자 물수지 모형의 개발 및 적용-)

  • 김대식;정하우
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.37 no.3_4
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    • pp.23-33
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    • 1995
  • Geographic data which are difficult to handle by the characteristics of spatial variation and variety turned into a possibility to analyze with tlie computer-aided digital map and the use of Geographic Information System(GIS). The purpose of this study is to develop and apply a GIS application model (GISCELWAB) for the spatial simulation of surface runoff from a small watershed. This paper discribes the modeling procedure and the applicability of the cell water balance model (CELWAB) which calculates the water balance of a cell and simulates surface runoff of watershed simultaneously by the interaction of cells. The cell water balance model was developed to simulate the temporal and spatial storage depth and surface runoff of a watershed. The CELWAB model was constituted by Inflow-Outflow Calculator (JOC) which was developed to connect cell-to-cell transport mechanism automatically in this study. The CELWAB model requests detail data for each component of a cell hydrologic process. In this study, therefore, BANWOL watershed which have available field data was selected, and sensitivity for several model parameters was analyzed. The simulated results of surface runoff agreed well with the observed data for the rising phase of hydrograph except the recession phase. Each mean of relative errors for peak discharge and peak time was 0.21% and2.1 1% respectively. In sensitivity analysis of CELWAB , antecedent soil moisture condition(AMC) affected most largely the model.

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Safety Computer System, CPCS Design in Nuclear Power Plant (안전등급 컴퓨터, 노심보호계산기계통 설계)

  • Sohn, Se-Do;Young Suh;Kang, Byung-Heon;Shin, Ji-Tae;Chun, Chong-Son
    • Nuclear Engineering and Technology
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    • v.26 no.4
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    • pp.502-506
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    • 1994
  • The design of safety computer system is described along with the case of software design and testing in the Core Protection Calculator System (CPCS). The application of computer system in safety system requires not only hardware qualification but thorough testing on software to verify its correctness and completeness. The testing on software for CPCS is performed by comparing the outputs of two versions of code. One is implemented in assembly language and the other is in Fortran. The testing is performed in sequencial and overlapping manner. Phase I test verifies that each software module is implemented correctly by executing every branch. Phase II test verifies that the integrated software is complete, meeting its requirements specification and also the integrated system meet its requirement and timing constraints. Through these testing, the Yonggwang Nuclear Power Plant Units (YGN) 3 and 4 CPCS software is verified to be correct and complete, and the integrated system is designed as in its requirements specification.

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