• 제목/요약/키워드: box method

검색결과 1,870건 처리시간 0.027초

가변 구속상자를 이용한 점-표면배정방법에 의한 표면실장 솔거페이스트의 삼차원 해석 및 검사 (3-D Analysis and Inspection of Surface Mounted Solder Pastes by Point-to-Surface)

  • 신동원
    • 한국정밀공학회지
    • /
    • 제20권3호
    • /
    • pp.210-220
    • /
    • 2003
  • This work presents a method of point to surface assignment fur 3D metrology of solder pastes on PCB. A bounding box enclosing the solder paste tightly on all sides is introduced to avoid incorrect assignment. The shape of bounding box fur solder paste brick is variable according to geometry of measured points. The surface geometry of bounding box is obtained by using five peaks selected in the histogram of normalized gradient vectors. By using the bounding box enclosing the solder pastes, the task of point-to-surface assignment has been successfully conducted, then geometrical features are obtained through the task of surface fitting.

Mode Matching Technique in a Cylindrical Cavity with Center Wire

  • Han, Dae Hyun
    • Journal of Multimedia Information System
    • /
    • 제5권2호
    • /
    • pp.143-146
    • /
    • 2018
  • The eigen value problem of a coaxial cavity and a modified pill box cavity is investigated using the mode matching technique. The coaxial cavity has a cylindrical cavity with beam ports and center conductor. The pill box cavity is the same as a coaxial cavity without center conductor. The electric field and magnetic field are formulated in propagation region and resonance region. The boundary and orthogonal conditions are applied to the electric and magnetic fields. We derived the eigen value equation by the proposed procedure in a coaxial cavity and a modified pill box cavity. The electromagnetic field of the real structure is disturbed by the coaxial wire. The effect of the coaxial wire in pill box cavity with beam ports increase the dominant resonant frequency. The coaxial line method of the coupling impedance is not adequate for a cylindrical cavity. The results of the mode matching technique and simulation agree well. The results confirm the proposed formulation is valid.

암호 함수의 구성 방법에 관한 연구 (A Study on the Construction Methods of Cryptographic Functions)

  • 김광조;;;박한규
    • 한국통신학회논문지
    • /
    • 제16권1호
    • /
    • pp.101-114
    • /
    • 1991
  • DES like 암호계에서 S(ubstitution) box는 암호계의 비선형성과 안전성을 결정하는 가장 중요한 요소이다. 본 논문에서는 입력의 임의의 한 빗도의 변화에 대하여 모든 출력 빗트가 1/2의 확률로 변화하는 SAC(Strict Avalanche Criterion) 조건을 만족하는 비설형 S-box의 구성 방법과 어울려, 최대차 SAC 조건을 만족하는 bijective S-box의 구성 방법에 대하여도 제안하였다. 또한, 제안한 구성 방법에 의한 S-box의 실례를 제시하였다.

  • PDF

IoU의 최적화에 관한 연구 (A Study on the Optimization of IoU)

  • 서신
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2020년도 춘계학술발표대회
    • /
    • pp.595-598
    • /
    • 2020
  • IoU (Intersection over Union) is the most commonly used index in target detection. The core requirement of target detection is what is in the image and where. Based on these two problems, classification training and positional regression training are needed. However, in the process of position regression, the most commonly used method is to obtain the IoU of the predicted bounding box and ground-truth bounding box. Calculating bounding box regression losses should take into account three important geometric measures, namely the overlap area, the distance, and the aspect ratio. Although GIoU (Generalized Intersection over Union) improves the calculation function of image overlap degree, it still can't represent the distance and aspect ratio of the graph well. As a result of technological progress, Bounding-Box is no longer represented by coordinates x,y,w and h of four positions. Therefore, the IoU can be further optimized with the center point and aspect ratio of Bounding-Box.

프리스트레스트 콘크리트 박스 거더의 종방향 프리스트레싱에 의한 슬래브의 횡방향 응력 (Transverse Stress of Slabs due tp Longitudinal Prestressing in Prestressed Concrete Box Girders)

  • 양인환
    • 콘크리트학회논문집
    • /
    • 제15권5호
    • /
    • pp.679-688
    • /
    • 2003
  • 종방향 텐던이 경사진 복부에 배치되는 박스 거더의 경우 프리스트레스 힘은 종방향 뿐만 아니라 횡방향 거동에도 영향을 미친다. 본 논문에서는 종방향 프리스트레싱에 의해 유발되는 횡방향 효과를 산정하는 기법을 제안하였다. 박스 거더의 유한요소 정식화 및 종방향 프리스트레싱 해석에 의해 프리스트레스 분포를 산정한 후, 이를 이용하여 횡방향 등가하중을 산정한다. 제안기법에 의한 수치해석결과와 기존의 접판법에 의한 수치해석결과는 유사하며, 이는 본 기법이 합리적임을 나타낸다. 제안기법을 이용하여 박스 거더 슬래브의 횡방향 거동을 분석하였다. 수치분석은 복부경사각, 텐던 편심에 대한 경간 길이비 등과 같은 주요 변수를 통해 수행되었다. 전형적인 단면 조건에서 종방향 프리스트레싱 효과만을 고려할 때, 박스 거더 슬래브의 횡방향 응력은 크지 않은 것으로 나타난다. 그러나, 복부 경사각이 50도 이하로 과도하게 작아지거나 텐던 편심에 대한 경간 길이비가 28이하로 작아지는 경우에는 교량 설계시 횡방향 응력의 크기를 고려할 필요가 있다고 사료된다.

느타리버섯 멀칭재배 방법과 수확도구 (Mulching Cultivation Method and Harvesting Implement of Pleurotus ostreatus)

    • 한국자원식물학회지
    • /
    • 제12권3호
    • /
    • pp.179-185
    • /
    • 1999
  • 본 연구에서 얻어진 느타리버섯 멀칭재배의 결과를 요약하면 다음과 같다. 1) 상자재배 방법은 관행시 1695g/상자, 흑색비닐 멀칭시 24.2%가 증수된 2237g/상자, 백색비닐 멀칭시 16.4%가 증수된 2028g/상자이었다. 2) 균상재배 방법은 관행시 48.2kg/3.3m$^2$ 흑색비닐 멀칭시 57.5kg/3.3m$^2$, 백색비닐 멀칭시 52.1kg/3.3m$^2$로 각각 16.2%와 7.5%의 증수 효과가 있었다. 3) 자루재배시 느타리버섯의 발이구멍 직경은 5~30mm, 간격은 10cm일 경우 양호하였다. 4) 느타리 버섯 멀칭재배는 세균성갈변병, 푸른곰팡이, 버섯파리의 예방효과가 있었다. 5) 느타리버섯 흑색 비닐멀칭 자루재배는 균상, 상자, 봉지재배 보다 수량이 많고 품질이 좋았다. 6) 멀칭 수확도구는 45~120cm $\times$ 45~200cm 길이가 적당하였다.

  • PDF

역도 인상기술 향상을 위한 부분 동작 강화훈련법 개발 및 운동학적 평가 (Development and Kinematic Evaluation for Training Method to Strengthen Part Motion of Snatch in Weight Lifting)

  • 문영진;권안숙;이계산
    • 한국운동역학회지
    • /
    • 제21권2호
    • /
    • pp.153-159
    • /
    • 2011
  • The purpose of this study was to develop an innovative training model and method to improve the posture and motion, while pulling up during weight lifting by evaluating the problems of Korean weight lifters performing this motion. To investigate the effectiveness of the new training method substitute members of the Korean national weight lifting team performed both the original pull up technique and new pulling training technique while kinetics and kinematics were recorded. For this study, the first phase of the new training method is more appropriate than the original training with the pull up drop slow deadlift to the knee joint. For the second phase, the new training motion is deemed to be more effective than the current box deadlift motion. Also, this new motion corrects the posture as there is more anterior hip joint motion(about 10 cm) and the knee flexes to about 120 degrees. For the third phase, starting about 10cm above the knee the box snatch high pull up is identified as a more suitable training method. For the forth phase, the box top snatch method is judged to be a more effective training method than the original top snatch training method.

단주교각 강박스교량의 거동계수 (Behavior Factor of a Steel Box Bridge with Single Column Piers)

  • 박준봉;김종수;국승규
    • 한국지진공학회:학술대회논문집
    • /
    • 한국지진공학회 2002년도 춘계 학술발표회 논문집
    • /
    • pp.228-235
    • /
    • 2002
  • As the response spectrum method generally used in the earthquake resistant design is a linear method, the nonlinear behavior of a structure is to be reflected with a specific factor. Such factors are provided in the "Design Criteria for Roadwaybridges"as response modification factors and in the Eurocode 8, Part 2 as behavior factors. In this study a 5-span steel box bridge with single column piers is selected and the behavior factor is determined. The linear time history analyses are carried out with a simple linear model, where the nonlinear behavior of piers leading to the ductile failure mechanism is considered as predetermined characteristic curves.

  • PDF

Box-Behnken법을 이용한 매입형 영구자석 동기전동기의 회전자 구조 최적설계 (Optimal Design of the Rotor Structure by using Box-Behnken Method for IPMSM)

  • 한정호;김원호;장익상;김미정;이기덕;이재준;이주
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2011년도 제42회 하계학술대회
    • /
    • pp.949-950
    • /
    • 2011
  • There are various ways of optimizing rotor design of Interior Permanent Magnet Synchronous Motors(IPMSM). In this paper, the best optimized design value was found by varying the Bridge thickness of PM in the rotor and changing Rib. The set design values were torque, 5 harmonics, 7 harmonics, and safety factor. Also, in order to make practical design value easily and quickly for optimization, Box-Behnken of Response Surface Method(RSM) method was used. Therefore, IPMSM resulted an optimized design model with high torque, low harmonics, and constant value of safety factor.

  • PDF

층화이중추출을 이용한 결합 확률화응답기법 (A Combined Randomized Response Technique Using Stratified Two-Phase Sampling)

  • 홍기학
    • 응용통계연구
    • /
    • 제17권2호
    • /
    • pp.303-310
    • /
    • 2004
  • 본 연구에서는 민감한 모집단에 대한 자료수집 방법으로 직접 질문 방법 인 Black-Box 방법과 간접 질문 방법인 확률화응답기법(RRT)의 결합적 방법을 제시하였고, 층화이중추출방법을 이용하여 모수를 추정하였다. 또한, 주어진 추정량의 효율성을 Mangat과 Singh 추정량과 비교 분석하였다.