• 제목/요약/키워드: Flattening method

검색결과 93건 처리시간 0.027초

신발패턴의 3차원 설계를 위한 곡면의 평면전개에 관한 연구 (A Study on Surface Flattening for 3 Dimensional Shoe Pattern Design)

  • 송성재;김성환
    • 한국CDE학회논문집
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    • 제9권3호
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    • pp.266-275
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    • 2004
  • In this paper, a method for generating the planar developments of three-dimensional shoe upper surfaces is proposed. This method is based on the optimization technique minimizing the geometric error occurred on the developed planar surface. Additionally, a rapid mapping algorithm to transform a curve on flattened plane to original surface (or vice versa) is proposed. These techniques are implemented on the 2D/3D integrated shoe design system. Using this system, a prototype running shoe can be designed more precisely and can be manufactured more quickly.

Time-of-Use 가격 및 실제 데이터를 고려한 전기 자동차 스마트 충전기법에 대한 연구 (A Study on EVs Smart Charging Scheme Considering Time-of-Use Price and Actual Data)

  • 김준혁;김철환
    • 전기학회논문지
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    • 제65권11호
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    • pp.1793-1799
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    • 2016
  • As one of the main trends in global industries is eco-friendly energy, the interest on Electric Vehicle(EV) has been increased. However, if large amount of EVs start to charging, it could cause rapid increase in demand power of the power system. To guarantee stable operation of the power system, those unpredictable power consume should be mitigated. In this paper, therefore, we propose a practical smart EVs charging scheme to prevent the rapid increase of the demand power and also provide load flattening function. For that we considered Time-of-Use(ToU) price and actual data such as driving pattern and parameters of distribution system. Simulation results show that the proposed method provides proper load flattening function while preventing the rapid increase of the demand power of the power system.

신발 곡면의 3차원 격자 데이터의 평면화에 관한 연구 (A Study on the Flattening of 3D Mesh data of Shoes)

  • 김영봉;이윤정
    • 게임&엔터테인먼트 논문지
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    • 제2권1호
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    • pp.64-70
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    • 2006
  • 캐드(CAD) 시스템은 우리가 사용하는 대부분의 산업 제품을 제작하는데 필수적으로 사용되고 있는 중요한 기술로 알려져 있다. 이러한 캐드 기술은 최근 컴퓨터 그래픽스 기술의 발달과 더불어 3차원 캐드 시스템으로 영역을 확장해 나가고 있다. 특히 신발 제조와 같은 특수한 영역의 CAD 시스템들도 3차원 캐드로 발전해 나가고 있다. 신발 설계를 위한 3차원 캐드 시스템은 가죽이나 천 같은 2차원의 부품들을 붙여서 3차원의 제품을 생산하는 작업의 특성상 2차원 데이터와 3차원 데이터 간의 호환성을 제공해야 한다. 또한 실제 작업 현장에서 일하는 많은 신발 캐드 디자이너들은 2차원 CAD환경에 더 익숙하며 작업 효율도 높다. 그러므로 3차원 신발 모델링과 2차원 모델링 사이의 변환은 3차원 캐드시스템에서 무엇보다 중요하다. 본 논문에서는 신발과 같은 3차원 모델의 격자 데이터를 2차원 데이터로 변환하기 위한 평면화(flattening) 방법을 제안한다.

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유선추적(流線追跡)에 의(依)한 실용선형(實用船型) 결정법(決定法)에 관(關)한 연구(硏究) (A Study on the Determination of a Practical Ship Hull Form by the Streamline Tracing Method)

  • 조규종
    • 대한조선학회지
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    • 제8권1호
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    • pp.1-16
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    • 1971
  • Ship hulls obtained by the streamline tracing method usually have characteristically drooped keel lines at the bottom, and a flattening of these bottoms would contribute considerably in utilizing these analytically obtainable hull forms in practical usage. In this dissertation, the author deals with a study on the determination of a practical hull form by the streamline tracing method with a particular emphasis on the bottom flattening problem. Investigations are centered around the form and the terms of bottom doublet distribution. Several examples are computed by varying bottom doublet sheet systematically while the main side source distribution is kept the same. The following conclusions are obtained based on those computed results: after the strength of a bottom doublet sheet can be determined more easily and efficiently by employing the concept of a control plane. If the distance from the distributed plane of the bottom doublet sheet to the control plane is defined as the control distance, the strength of the bottom doublet sheet, the flatness of traced lines, and the increment of the beam length ratio by adding the bottom doublet sheet are all related to the control distance by linear equations near the design bottom. It is observed that a better result can be obtained by using a "line-sampling method" for ${\zeta}_K>2T/L$, and a "plane-sampling method" for ${\zeta}_K{\leq}2T/L$, provided that the check points are sampled in the range ${\xi}{\leq}0.7$.

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전력(電力) 부하평준화(負荷平準化) 방안(方案) (The Suggested Methods for Electric Load Flattening)

  • 조규승;윤갑구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1985년도 하계학술회의논문집
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    • pp.144-147
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    • 1985
  • In electricity industry, the improvement of load factor by flattening of load has been considered to be more important than any other tasks and has received wide concern and interest. Especially while annual peak load had occured early evening in winter during past decades, but we found the trend has changed so that annual peak load occured during the daytime in summer since1981 The useful practicing methods of this load management ale as follows; 1. Inducing of midnight load by thermal storage water heating 2. Seasonal differential rates. 3. Revising the peak load priceing (Time-of -use) It seems hard to expect that load research can be carried out in a short time, and we all have to exert outselves continuously to provide efficient load management method without wasting resources.

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평삭공정에서 경면가공을 위한 단결정 및 다결정 다이아몬드 다중공구의 가공성 평가 (Comparison of Machinability Between PCD Tool and SCD Tool for Large Area Mirror Surface Machining Using Multi-tool by Planer)

  • 김창의;최환진;전은채;제태진;강명창
    • 한국분말재료학회지
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    • 제20권4호
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    • pp.297-301
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    • 2013
  • Mirror surface machining for large area flattening in the display field has a problem such as a tool wear and a increase in machining time due to large area machining. It should be studied to decrease machining time and tool wear. In this paper, multi-tool machining method using a PCD tool and a SCD tool was applied in order to decrease machining time and tool wear. Machining characteristics (cutting force, machined surface and surface roughness) of PCD tool and SCD tool were evaluated in order to apply PCD tool to flattening machining. Based on basic experiments, the PCD/SCD multi-tool method and the SCD single-tool method were compared through surface roughness and machining time for appllying large area mold machining.

Positional correction of a 3D position-sensitive virtual Frisch-grid CZT detector for gamma spectroscopy and imaging based on a theoretical assumption

  • Younghak Kim ;Kichang Shin ;Aleksey Bolotnikov;Wonho Lee
    • Nuclear Engineering and Technology
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    • 제55권5호
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    • pp.1718-1733
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    • 2023
  • The virtual Frisch-grid method for room-temperature radiation detectors has been widely used because of its simplicity and high performance. Recently, side electrodes were separately attached to each surface of the detectors instead of covering the entire detector surface with a single electrode. The side-electrode structure enables the measurement of the three-dimensional (3D) gamma-ray interaction in the detector. The positional information of the interaction can then be utilized to precisely calibrate the response of the detector for gamma-ray spectroscopy and imaging. In this study, we developed a 3D position-sensitive 5 × 5 × 12 mm3 cadmium-zinc-telluride (CZT) detector and applied a flattening method to correct detector responses. Collimated gamma-rays incident on the surface of the detector were scanned to evaluate the positional accuracy of the detection system. Positional distributions of the radiation interactions with the detector were imaged for quantitative and qualitative evaluation. The energy spectra of various radioisotopes were measured and improved by the detector response calibration according to the calculated positional information. The energy spectra ranged from 59.5 keV (emitted by 241Am) to 1332 keV (emitted by 60Co). The best energy resolution was 1.06% at 662 keV when the CZT detector was voxelized to 20 × 20 × 10.

고음질 음성합성을 위한 LSP를 이용한 피치검출 성능향상에 관한 연구 (A Study on the Pitch Extraction Improvement Using LSP for the Synthesis of High Speech Quality)

  • 서지호;김종국;배명진
    • 한국음향학회지
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    • 제29권1호
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    • pp.69-75
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    • 2010
  • 본 논문에서는 스펙트럼 신호를 최대한 평탄화시킴으로써 포만트의 영향을 제거하고 고조파 성분을 분리해 내어 이를 피치검출에 사용한다. 스펙트럼 신호로부터 포만트의 영향과 천이진폭의 영향을 제거하기 위해 주파수 대역을 LSP(Line Spectrum Pair)를 기준으로 서브밴드로 나누고 각각의 서브밴드에서 기울기를 취한 후에 역기울기로 스펙트럼을 보상한다. 실험 결과 제안한 방법이 LPC법, Lifter법, Cepstrum법을 이용하여 평탄화시킬 때 보다 평탄화 정도가 좋아짐을 알 수 있다. 또한 제안한 방법 이외에 가장 양호한 성능을 나타낸 LPC법을 이용하여 피치를 구했을 때 제안한 방법의 조오율이 평균 1.30% 감소하였다. 또한 제안한 방법은 잡음을 부가한 음성의 경우에도 낮은 에러율을 보여 배경잡음에 강하다는 것을 알 수 있었다.

이중 SQI를 이용한 TFT-LCD 결함 검출 (TFT-LCD Defect Detection Using Double-Self Quotient Image)

  • 박운익;이규봉;김세윤;박길흠
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제14권6호
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    • pp.604-608
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    • 2008
  • TFT-LCD영상은 불균일한 휘도 변화를 어느 정도 허용하고 있으며, 영상 전반에 걸쳐 나타나는 큰 휘도 변화는 국부적으로 주변 영역과 차이가 나는 결함 영역을 찾는데 방해가 된다. SQI(Self Quotient Image)는 얼굴 인식 분야에서 저주파에 해당하는 조명성분을 제거 하는데 사용되어 왔으며, 일종의 High Pass Filter(고주파 통과 필터) 형태이다. 본 논문에서는 SQI가 신호의 저주파 성분을 평활화 하는 효과를 가지면서 국부적인 변화를 유지하는 특성을 가지는데 착안하여, TFT-LCD영상에 존재하는 결함을 강조하는 알고리즘을 제안하였다. 제안한 방법을 기존의 TFT-LCD영상 전처리 방법들과 비교하였을 때, 평활화 효과 및 결함 영역 강조 효과가 우수함을 확인할 수 있었다.

Development of a Pad Conditioning Method for ILD CMP using a High Pressure Micro Jet System

  • Lee, Hyo-Sang;DeNardis, Darren;Philipossian, Ara;Seike, Yoshiyuki;Takaoka, Mineo;Miyachi, Keiji;Doi, Toshiro
    • Transactions on Electrical and Electronic Materials
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    • 제8권1호
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    • pp.26-31
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    • 2007
  • The goal of this study is to determine if High Pressure Micro Jet (HPMJ) conditioning can be used as a substitute for, or in conjunction with, conventional diamond pad conditioning. Five conditioning methods were studied during which 50 ILD wafers were polished successively in a 100-mm scaled polisher and removal rate (RR), coefficient of friction (COF), pad flattening ratio (PFR) and scanning electron microscopy (SEM) measurements were obtained. Results indicated that PFR increased rapidly, and COF and removal rate decreased significantly, when conditioning was not employed. With diamond conditioning, both removal rate and COF were stable from wafer to wafer, and low PFR values were observed. SEM images indicated that clean grooves could be achieved by HPMJ pad conditioning, suggesting that HPMJ may have the potential to reduce micro scratches and defects caused by slurry abrasive particle residues inside grooves. Regardless of different pad conditioning methods, a linear correlation was observed between temperature, COF and removal rate, while an inverse relationship was seen between COF and PFR.