• Title/Summary/Keyword: 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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    • v.3 no.1
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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
    • IEMEK Journal of Embedded Systems and Applications
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    • v.12 no.1
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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.

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

  • Kang, Y.C.;Kim, D.S.;Lee, W.H.;Park, J.Y.;Ou, H.R.;Park, Y.S.
    • Clinical and Experimental Reproductive Medicine
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    • v.20 no.2
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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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    • v.35 no.11
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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.

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

  • Kweon, Dae-Cheol;Hong, Sung-Man;Park, Peom
    • IE interfaces
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    • v.15 no.4
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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.

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

  • Park, S.H.;Oh, I.Y.;Han, S.W.;Woo, Y.Y.;Hwang, T.W.;Seyedkashi, S.M.H.;Moon, Y.H.
    • Transactions of Materials Processing
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    • v.26 no.1
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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.

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

  • Chung Woong-Yoon;Chang Hang-Seok;Lee Jong-Doo;Park Cheong-Soo
    • Korean Journal of Head & Neck Oncology
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    • v.15 no.2
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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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    • v.50
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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.

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

  • Lee, Young-Heon;Moon, Tae-Wha
    • Korean Journal of Food Science and Technology
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    • v.26 no.3
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    • pp.288-294
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    • 1994
  • Dietary fiber contents in brans of the two representative Korean rice varieties, Chucheong and Sucheon were measured by the AOAC method, and the composition of total dietary fiber (TDF) was analyzed with the acid detergent fiber (ADF) procedure. Rice bran contained more than 25% of TDF, most of which was insoluble dietary fiber. Hemicellulose was shown to be the major constituent and rice bran dietary fiber contained distinctive amounts of cellulose and uronic acid. Consecutive acidalkaline treatment of rice bran considerably increased soluble dietary fiber (SDF) content and water-holding capacity (WHC). WHC of wheat flour-rice bran dietary fiber mixture increased with the proportion of rice bran dietary fiber. Analysis of the differential scanning calorimetry thermograms revealed that rice bran dietary fiber effectively retarded retrogradation of wheat starch.

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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
    • Journal of Integrative Natural Science
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    • v.4 no.3
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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.