• 제목/요약/키워드: Consecutive scanning

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Mobile Robot Localization using Range Sensors: Consecutive Scanning and Cooperative Scanning

  • Lee Sooyong;Song Jae-Bok
    • International Journal of Control, Automation, and Systems
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    • 제3권1호
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    • pp.1-14
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    • 2005
  • This paper presents an obstacle detection algorithm based on the consecutive and the cooperative range sensor scanning schemes. For a known environment, a mobile robot scans the surroundings using a range sensor that can rotate 3600°. The environment is rebuilt using nodes of two adjacent walls. The robot configuration is then estimated and an obstacle is detected by comparing characteristic points of the sensor readings. In order to extract edges from noisy and inaccurate sensor readings, a filtering algorithm is developed. For multiple robot localization, a cooperative scanning method with sensor range limit is developed. Both are verified with simulation and experiments.

Mutual Interference on Mobile Pulsed Scanning LIDAR

  • Kim, Gunzung;Eom, Jeongsook;Choi, Jeonghee;Park, Yongwan
    • 대한임베디드공학회논문지
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    • 제12권1호
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    • pp.43-62
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    • 2017
  • Mobile pulse scanning Light Detection And Ranging (LIDAR) are essential components of intelligent vehicles capable of autonomous travel. Obstacle detection functions of autonomous vehicles require very low failure rates. With the increasing number of autonomous vehicles equipped with scanning LIDARs to detect and avoid obstacles and navigate safely through the environment, the probability of mutual interference becomes an important issue. The reception of foreign laser pulses can lead to problems such as ghost targets or a reduced signal-to-noise ratio. This paper will show the probability that any two scanning LIDARs will interfere mutually by considering spatial and temporal overlaps. We have conducted four experiments to investigate the occurrence of the mutual interference between scanning LIDARs. These four experimental results introduced the effects of mutual interference and indicated that the interference has spatial and temporal locality. It is hard to ignore consecutive mutual interference on the same line or the same angle because it is possible the real object not noise or error. It may make serious faults because the obstacle detection functions of autonomous vehicle rely on heavily the scanning LIDAR.

초음파를 이용한 배란의 연속관찰 (Consecutive Scanning of Ovulation Via Transvaginal Sonography)

  • 강윤철;김동석;이우호;박준영;오혜련;박영선
    • Clinical and Experimental Reproductive Medicine
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    • 제20권2호
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    • pp.131-135
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    • 1993
  • The ultrasonographic examination with vaginal probe(5MHz) was undertaken in 101 patients at infertility clinic of Eul-Ji General Hospital. This study was performed to evaluate the number of mature follicles per menstrual cycle, the relationship of both ovaries for consecutive ovulatory cycle and the responsiveness of follicular growth followed by administration of ovulation inductant. The results were as follows; 1. The ovulation induction group with clomiphene citrate showed more follicles than natural menstrual cycle group. 2. Each means of numbers of follicles between ovaries showed no difference between natural and ovulatory induction groups. 3. The rate of follicular growth per one menstrual cycle showed higher in the clomiphene citrate induced cycle group. 4. Clomiphene citrate induced group tends to be easier for multiple follicular growth but had no significant difference in statistics. 5. The ipsilateral Vs. contralateral follicular growth rate for consecutive menstrual cycles in both ovaries showed no significant difference between two groups.

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Preparation of Silica Hollow Composite Particles

  • Lee, Dong Hoon;Lee, Chang Hyun
    • Bulletin of the Korean Chemical Society
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    • 제35권11호
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    • pp.3303-3306
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    • 2014
  • A facile and effective approach has been developed to prepare hybrid hollow microspheres, via consecutive processes of pickering mini-emulsion polymerization for core-shell formation, and calcination of the sacrificial core. The resulting hollow composite particles have mono-layered shells. The morphology and size characteristics of synthesized composite particles were investigated, using dynamic light scattering (DLS) and scanning electron microscopy (SEM) measurements.

CT 검사에서 시간분석에 의한 필름시스템과 PACS의 비교 연구 (Comparison of Time Analysis on the Film Based System Versus PACS in the CT Scanning)

  • 권대철;홍성만;박범
    • 산업공학
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    • 제15권4호
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    • pp.439-443
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    • 2002
  • In this paper, we study to evaluate the relative time required to perform the CT scanning in the PACS versus a film-based system and helical versus non-helical studies. Time studies were performed in 175 consecutive CT scanning. Images from 85 examinations were electronically transferred to a PACS, and 90 were printed to film. The time required to obtain and electronically transfer the images or print the images to film and make the current and previous studies available to the radiologists for interpretation was recorded. The time required for a radiological technologist to complete a CT test was reduced by 43% with the PACS compared with the film-based system and nonhelical was reduced 10~20% with helical studies. This reduction was due to the elimination of a transfer and printing, such as the printing at window or level settings. The use of PACS can result in the elimination of time tasks for the radiological technologist, resulting in marked reduction in examination time. This reduction can result in decreased cost and increased productivity in PACS operation.

수중 레이저 굽힘시 SUS430/Cu/SUS430 복합판재 성형 특성 분석 (Parameter Characterization for Underwater Laser forming of SUS430/Cu/SUS430 Laminated Composite Layer)

  • 박성환;오일영;한상욱;우영윤;황태우;;문영훈
    • 소성∙가공
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    • 제26권1호
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    • pp.35-40
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    • 2017
  • Laser forming is an advanced process in sheet metal forming in which thermal stress originated from the laser heat source is used to shape the metal sheet. However, substantial waiting time is normally necessary for the workpiece to cool down between consecutive scans so that a steep temperature gradient can be reestablished in the next scan. In order to solve this drawback, laser bending characteristics are experimentally implemented in underwater condition. Laser forming effects under various conditions, including different laser power, scanning velocity, beam diameter, number of passes and material, are investigated. The results show that the underwater laser forming facilitates deliberate forming. The bending angle per respective laser scan is decreased with increasing the number of passes and scanning velocity.

최소침습 방사능 유도 부갑상선 수술 (Minimally Invasive Radio-guided Parathyroid Surgery)

  • 정웅윤;장항석;이종두;박정수
    • 대한두경부종양학회지
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    • 제15권2호
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    • pp.194-199
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    • 1999
  • Introduction: Since 1996, Dr. James Norman has successfully performed mimimally invasive radio-guided parathyroidectomy(MIRP) using intraoperative nuclear mapping with $^{99m}Tc$ sestamibi scanning and radioactivity detection probe. Objectives: We aimed to introduce this new surgical technique and evaluate it's efficacy by our own experiences. Method: From May to October 1999, five consecutive patients with primary hyperparathyroidism underwent parathyroidectomy by using modified MIRP technique. $^{99m}Tc$ sestamibi scanning was performed 1.0 or 1.5 hour before operation. After intraoperative localization of the tumor under the guidance of quantitative gamma counting with a NEVIGATOR probe, an unilateral small skin incision(3.0-4.0cm) was placed. Without a skin flap, the strap muscle was directly divided with the use of a Harmonic scalpel. After careful dissection, the parathyroid tumor was removed. Result: In all patients, a single adenoma could be easily detected and removed by this new technique. Mean incision length was 3.2cm(3.0-4.0cm) and operative time ranged from 40 to 110minute. All the patients were discharged within 2 days of surgery without any complication. Conclusion: This new operative technique could become the most minimally invasive alternative to the standard operative procedure for parathyroid adenoma.

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Noise2Atom: unsupervised denoising for scanning transmission electron microscopy images

  • Feng Wang;Trond R. Henninen;Debora Keller;Rolf Erni
    • Applied Microscopy
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    • 제50권
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    • pp.23.1-23.9
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    • 2020
  • We propose an effective deep learning model to denoise scanning transmission electron microscopy (STEM) image series, named Noise2Atom, to map images from a source domain 𝓢 to a target domain 𝓒, where 𝓢 is for our noisy experimental dataset, and 𝓒 is for the desired clear atomic images. Noise2Atom uses two external networks to apply additional constraints from the domain knowledge. This model requires no signal prior, no noise model estimation, and no paired training images. The only assumption is that the inputs are acquired with identical experimental configurations. To evaluate the restoration performance of our model, as it is impossible to obtain ground truth for our experimental dataset, we propose consecutive structural similarity (CSS) for image quality assessment, based on the fact that the structures remain much the same as the previous frame(s) within small scan intervals. We demonstrate the superiority of our model by providing evaluation in terms of CSS and visual quality on different experimental datasets.

미강 식이섬유의 조성과 보수력 및 전분노화에 미치는 영향 (Composition, Water-Holding Capacity and Effect on Starch Retrogradation of Rice Bran Dietary Fiber)

  • 이영헌;문태화
    • 한국식품과학회지
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    • 제26권3호
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    • pp.288-294
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    • 1994
  • 추청과 수천 두 품종의 벼에서 얻은 미강에 함유된 총 식이섬유를 AOAC방법으로 정량하였고, acid detergent fiber(ADF) 방법으로 식이섬유의 성분을 분석하였다. 미강의 식이섬유 함량은 25% 이상이었고 대부분 불용성이었다. 미강 식이섬유의 주성분은 헤미셀룰로오스이었으며 상당량의 셀룰로오스와 uronic acid가 특징적으로 함유되어 있었다. 화학적 처리에 의한 가용성 식이섬유(SDF)의 함량과 보수력(WHC)의 변화를 측정한 결과, 산과 알칼리를 연속적으로 처리한 경우에 SDF함량과 WHC가 뚜렷하게 증가하였다. 미강 식이섬유의 기능성을 조사하기 위하여 밀가루에 미강 식이섬유를 여러 가지 함량으로($0{\sim}100%$) 첨가하고 WHC를 측정한 결과, 식이섬유의 첨가량에 비례하여 밀가루의 WHC가 증가하였다. 또한 differential scanning calorimetry(DSC)로 얻은 thermogram으로부터 미강 식이섬유는 전분의 노화를 지연시킴을 알 수 있었다.

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Multiple-Bit Encodings of Bragg Photonic-structures by Using Consecutive Etch with Various Square Wave Currents

  • Lee, Bo-Yeon;Hwang, Minwoo;Cho, Hyun;Kim, Hee-Chol;Cho, Sungdong
    • 통합자연과학논문집
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    • 제4권3호
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    • pp.192-196
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    • 2011
  • New method to encode multiple photonic features of Bragg type reflector on silicon wafer has been investigated. Multiple bit encodes of distributed Bragg reflector features have been prepared by electrochemical etching of crystalline silicon by using various square wave current densities. Optical characterization of multi-encoding of distributed Bragg reflectors on porous silicon was achieved by Ocean optics 2000 spectrometer for the search of possible applications of multiple bit encoding of distributed Bragg reflectors such as multiplexed assays and chemical sensors. The morphology and cross-sectional structure of multi-encoded distributed Bragg reflectors was investigated by field emission scanning electron micrograph.