• 정보처리학회논문지A
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• 제12A권1호
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• pp.1-6
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• 2005

본 논문에서는 trace-back systolic array Viterbi algorithm의 저전력 생존 메모리 구현에 관한 새로운 알고리즘을 소개한다. 이 알고리즘의 핵심 아이디어는 trace back 연산의 수를 줄이기 위하여 이미 생성된 trace-back routes를 재사용하는 것이다. 그리고 trace-back unit의 불필요한 switching activity가 발생하는 영역을 gate-clock을 사용하여 전력소모를 줄이는 것이다. Synopsys Power Estimation 툴인 Design Power를 이용하여 전력소모를 측정하였고, 그 결과 [1]의 논문에서 소개된 trace-back unit 비하여 평균 $40{\%}$ 전력감소가 있었고, $23{\%}$의 면적증가를 보였다.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.84-89
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• 2007

This research was done on the basis of assumption that there is a relationship between welding parameters and geometry of the back-bead being a gap in arc welding. Multiple regression analysis was used as method for predicting the geometry of the back-bead. The analysis data and the verification data were used for the formation of multiple regression analysis. The method was used to perform the prediction of the back-bead.

• 한국전자파학회논문지
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• 제22권11호
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• pp.1054-1062
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• 2011

무인 차량의 야지 자율 주행을 위한 근거리 초광대역 bistatic 레이다에 적합한 시간 영역 영상화 기법의 구현에 대해 기술한다. 기존의 SAR(Synthetic Aperture Radar) 영상화 기법에서 주파수 영역에 기반을 둔 방법은 원전계 조건을 만족하는 응용 분야에는 잘 적용되지만, 근거리에 적용할 경우 근사화에 따른 위상 오차가 크게 되어 영상의 품질을 떨어뜨린다. 따라서 근거리 영상 레이다에서는 시간 영역에 기반을 둔 back-projection 방법이 적합하다. 그러나 back-projection의 경우 수행 시간이 매우 긴 단점이 있다. 따라서 시간 영역에 기반을 두고 영상의 품질은 back-projection과 유사하며, 수행 시간을 줄일 수 있는 방법으로 개발된 것이 FFBP(Fast Factorized Back-Projection) 방법이다. 야지에서 획득한 레이다 원시데이터를 사용하여 back-projection 방법과 FFBP 방법을 구현하고 영상의 품질 및 수행 시간을 비교하여 bistatic 전방 관측 레이다의 시간 영역 영상화 기법의 적용 가능성을 입증한다.

• Steel and Composite Structures
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• 제31권6호
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• pp.601-615
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• 2019

In cold-formed steel (CFS) structures, such as trusses, wall frames and columns, the use of back-to-back built-up CFS angle sections are becoming increasingly popular. In such an arrangement, intermediate fasteners are required at discrete points along the length, preventing the angle-sections from buckling independently. Limited research is available in the literature on the axial strength of back-to-back built-up CFS angle sections. The issue is addressed herein. This paper presents the results of 16 experimental tests, conducted on back-to-back built-up CFS screw fastened angle sections under axial compression. A nonlinear finite element model is then described, which includes material non-linearity, geometric imperfections and explicit modelling of the intermediate fasteners. The finite element model was validated against the experimental test results. The validated finite element model was then used for the purpose of a parametric study comprising 66 models. The effect of fastener spacing on axial strength was investigated. Four different cross-sections and two different thicknesses were analyzed in the parametric study, varying the slenderness ratio of the built-up columns from 20 to 120. Axial strengths obtained from the experimental tests and finite element analysis were used to assess the performance of the current design guidelines as per the Direct Strength Method (DSM); obtained comparison showed that the DSM is over-conservative by 13% on average. This paper has therefore proposed improved design rules for the DSM and verified their accuracy against the finite element and test results of back-to-back built-up CFS angle sections under axial compression.

• 한국소음진동공학회논문집
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• 제15권3호
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• pp.346-353
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• 2005

In this paper, the tension of assembly stay cable connected with massive anchorage block was calculated through back analysis of in-situ frequencies measured from a stadium structure. Direct approach to back analysis is adopted using the univariate method among the direct search methods as an optimization technique. The univariate method can search the optimal tension without regard to the initial ones and has a rapid convergence rate. To verify the reliability of back analysis, Tension formulas proposed by Zui et al. and Shimada were used. Tensions estimated by three methods are compared with the design tension, and are in a reasonable agreement with an error of more or less than 15%. Therefore, it is shown that back analysis applied in this paper is appropriate for estimation of cable tension force.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.435-440
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• 2004

In this paper, the tension of assembly stay cable connected with massive anchorage block was calculated through back analysis of in-situ frequencies measured from a stadium structure. Direct approach to back analysis is adopted using the univariate method among the direct search methods as an optimization technique. The univariate method can search the optimal tension without regard to the initial ones and has a rapid convergence rate. To verify the reliability of back analysis, Tension formulas proposed by Zui et al. and Shimada were used. Tensions estimated by three methods are compared with the design tension, and are in a reasonable agreement with an error of more or less than 15%. Therefore, it is shown that back analysis applied in this paper is appropriate for estimation of cable tension force.

• Physical Therapy Rehabilitation Science
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• 제2권1호
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• pp.27-30
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• 2013

Objective: Low back pain is a primary of source of dysfunction and economic costs. Gluteus medius muscle co-activation and activity pattern change caused the low back pain. Active release technique (ART) is a patented, non-invasive, soft tissue treatment process that both locates and breaks down the scar tissue and adhesions. The purpose of this study was to assess the effects on chronic low back pain using ART on gluteus medius so that suggest usable treatment method for treating chronic low back pain. Design: One group pretest-posttest design. Methods: Twelve patients with chronic low back pain were participated in this study. Subjects in ART group were received 2 times a week for 3 weeks treatments with either ART on gluteus medius muscle trigger points. Outcome measures were conducted by pain intensity with a pain visual analogue scale and pressure pain threshold on gluteus medius. Results: Completion of the intervention, the visual analogue scale was decreased in ART group (p<0.05). Also pressure pain threshold was decreased in ART group (p<0.05). Conclusions: Our results suggest that the response to ART may be usable to treat low back pain. ART was presented to reduce pain level of low back in people with chronic low back pain. Further study is required to management for low back pain due to gluteus medius and more ART study.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.484-487
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• 2002

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss. In this paper, the proto type mold transformer of 50kVA class is investigated by routine, type, special test. The outdoor energized aging test is investigated by back-to-back method to verify the long time performance of pole mold transformer. The aging process of transformer is analyzed by various diagnosis method such as DC voltage-current test, $tan{\delta}$, Meggar measurement, winding temperature and etc.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.77-78
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• 2016

본 논문에서는 양방향 전력공급이 가능한 3상 Back to Back 컨버터에 필요한 여러 가지 제어 기술들을 살펴보고 시뮬레이션을 통해 제어 알고리즘의 타당성을 분석하며, 입, 출력 전압, 전류 등 파형을 관찰하고 전력을 가변시킬 때 나타나는 3상 계통연계형 Back to Back 컨버터의 동특성을 개선하는 방법을 알아본다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 전력전자학술대회 논문집
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• pp.114-115
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• 2013

This paper proposes an estimation method of back emf for the sensorless controlled high speed PMSM drive in turbo compressors with air bearings. The back emf of PMSM motor varies due to the temperature variation, which deteriorates the control performance of sensorless controlled PMSM drives. The proposed method is based on the current model of the PMSM motor. The simulation results show that the proposed method estimates the back emf of sensorless controlled PMSM drives with reasonable accuracy for parameter adaptation.