• Title/Summary/Keyword: Single-shot

검색결과 234건 처리시간 0.042초

스프링강의 피로진전거동에 미치는 잔류응력의 영향 (A Study on The Effect of Residual Stress on Fatigue Propagation Behavior of Spring Steel)

  • 박경동;정찬기
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2002년도 추계학술대회 논문집
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    • pp.366-372
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    • 2002
  • Recently the steel parts used at automobiles are required to be used under high stress more than ever before in need of the weight down. To achieve this requirement of a high strength steel, it must be necessary to decrease inclusion content and surface deject as like decarburization, surface roughness etc.. In this study, the surface conditions are measured to know tile influence on fatigue properties by two cases of shot peening of two-stage shot peening and single-stage shot peening. And for this study, three kinds of spring steel (JISG4081-SUP7,SAE 9254, DIN 50CrV4, ) are made. This study shows the outstanding improvement of fatigue properties at tire case of two-stage shot peening in the rotary bending fatigue test and this is assumed to be from (1) Decreasing the surface roughness (2) Unchanging the surface hardness (3) Increasing the compressive residual stress But, results also show fatigue failures originated at inclusion near surface, and this inclusion type is turned out to be a alumina of high hardness.

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Single Shot White Light Interference Microscopy for 3D Surface Profilometry Using Single Chip Color Camera

  • Srivastava, Vishal;Inam, Mohammad;Kumar, Ranjeet;Mehta, Dalip Singh
    • Journal of the Optical Society of Korea
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    • 제20권6호
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    • pp.784-793
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    • 2016
  • We present a single shot low coherence white light Hilbert phase microscopy (WL-HPM) for quantitative phase imaging of Si optoelectronic devices, i.e., Si integrated circuits (Si-ICs) and Si solar cells. White light interferograms were recorded by a color CCD camera and the interferogram is decomposed into the three colors red, green and blue. Spatial carrier frequency of the WL interferogram was increased sufficiently by means of introducing a tilt in the interferometer. Hilbert transform fringe analysis was used to reconstruct the phase map for red, green and blue colors from the single interferogram. 3D step height map of Si-ICs and Si solar cells was reconstructed at multiple wavelengths from a single interferogram. Experimental results were compared with Atomic Force Microscopy and they were found to be close to each other. The present technique is non-contact, full-field and fast for the determination of surface roughness variation and morphological features of the objects at multiple wavelengths.

단결정 초내열합금의 재결정 방지를 위한 접합 전처리 조건에 관한 연구 (A Study on the Optimum Bonding Preparation Condition of Single Crystal Superalloy)

  • 김대업
    • Journal of Welding and Joining
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    • 제19권2호
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    • pp.191-199
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    • 2001
  • The oxidation and recrystallization behaviors of Ni-base single crystal superalloy, CMSX-2 were investigated to determine the condition of the preparation for transient liquid phase (TLP) bonding operations. The faying surfaces of CMSX-2 were worked by the shot peening, fine cutting and mechanical polishing treatments and the degree of working of treated surfaces was evaluated by the hardness test and X-ray diffraction method CMSX-2 was heat-treated at 1,173∼1.589k for 3.6ks in vacuum of 4mPa. The mechanically polished surface was slightly oxidized after heat treatment even in the vacuum atmosphere of 4mPa. The thickness of an oxide film increased with increasing the heating temperature and the surface roughness of the faying surface. Recrystallization occurred at the surface after heat treatment at above 1,423K when the hardness was increased more than Hv600 by the shot peening treatment while the mechanically polished or fine cut surfaces didn't recrystallized. Based on these results, it was clearfied that the mechanically polishing with fine abrasive grit could be used for the preparation of faying surface of CMSX-2 before bonding operation.

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원샷 파노라믹 스캐닝 기반 실시간 다수 얼굴 인식 시스템 (Real-time multiple face recognition system based on one-shot panoramic scanning)

  • 김대환
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2022년도 추계학술대회
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    • pp.553-555
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    • 2022
  • 본 논문은 원샷 파노라믹 스캐닝을 기반으로 하는 실시간 자동 얼굴 인식 시스템에 대한 것이다. 한 번의 파노라믹 스캐닝 프로세스를 통하여 실시간으로 다수의 얼굴을 검출하고 사전에 등록된 얼굴을 인식하는 것이다. 한 장의 파노라마 영상 내에서 다수 얼굴 인식을 하는 것이 아닌, 스캐닝 과정에서 얻어진 다수의 영상을 이용하여 얼굴을 인식하도록 한다. 이는 파노라마 영상 생성 시간과 스티칭(Stitching) 오류를 줄임과 동시에 다수 영상의 누적 정보를 활용하여 얼굴 인식 성능을 향상할 수 있다. 이는 간단한 영상 획득 장치만으로 다수 인원의 스마트 출결 시스템과 같은 다양한 응용 프로그램에 사용될 수 있을 것으로 예상한다.

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레이저 애벌레이션 분광을 이용한 고분자 표면의 나노미터 스케일 표면 분석 (Nanometer-Scale Surface Analysis of Polymers Using Laser Ablation Spectroscopy)

  • 김민규
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 C
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    • pp.1334-1336
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    • 2001
  • In this study, laser ablation atomic fluorescence (LAAF) spectroscopy has been applied for a nanometer-scale surface analysis of Na-doped polymethyl methacrylate (PMMA). LAAF spectroscopy is a new sensitive element detection technique which involves atomizing of a sample by the laser ablation and detection of ablated plume by laser-induced fluorescence (LIF) spectroscopy. Using this technique in the detection of Na atoms with Na-doped PMMA, a detection limit is obtained as 36 fg for single laser shot. Further, the depth distribution in the sample is measured with a very high spatial resolution using a two-layer PMMA sample by observing the shot-by-shot LIF intensity from the Na atoms.

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싱글숏 멀티박스 검출기에서 객체 검출을 위한 가속 회로 인지형 가지치기 기반 합성곱 신경망 기법 (Convolutional Neural Network Based on Accelerator-Aware Pruning for Object Detection in Single-Shot Multibox Detector)

  • Kang, Hyeong-Ju
    • 한국정보통신학회논문지
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    • 제24권1호
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    • pp.141-144
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    • 2020
  • Convolutional neural networks (CNNs) show high performance in computer vision tasks including object detection, but a lot of weight storage and computation is required. In this paper, a pruning scheme is applied to CNNs for object detection, which can remove much amount of weights with a negligible performance degradation. Contrary to the previous ones, the pruning scheme applied in this paper considers the base accelerator architecture. With the consideration, the pruned CNNs can be efficiently performed on an ASIC or FPGA accelerator. Even with the constrained pruning, the resulting CNN shows a negligible degradation of detection performance, less-than-1% point degradation of mAP on VOD0712 test set. With the proposed scheme, CNNs can be applied to objection dtection efficiently.

증강현실을 위한 객체인식 기술 성능 비교 (Object Recognition Technology Performance Comparison for Augmented Reality)

  • 신은지;신광성
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2021년도 춘계학술대회
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    • pp.348-350
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    • 2021
  • 증강현실의 핵심기술은 객체인식기술이다. 최근 CNN등 댜양한 인공지능 알고리즘의 개발로 인하여 영상s에서 특정 객체를 효과적으로 구분하는 것이 가능해졌다. 객체를 빠르고 정확하게 인식하는 기술이 확보되어야 더욱 현실감있고 몰입감있는 증강현실 콘텐츠의 구현이 가능해진다. 본 연구에서는 SSD(single shot multibox detector)를 이용한 객체인식 모델과 YOLO를 이용한 객체 인식 모델의 비교평가를 수행하였다.

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