• Title/Summary/Keyword: low background

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Design of a Background Image Based Multi-Degree-of-Freedom Pointing Device (배경영상 기반 다자유도 포인팅 디바이스의 설계)

  • Jang, Suk-Yoon;Kho, Jae-Won
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.6
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    • pp.133-141
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    • 2008
  • As interactive multimedia have come into wide use, user interfaces such as remote controllers or classical computer mice have several limitations that cause inconvenience. We propose a vision-based pointing device to resolve this problem. We analyzed the moving image from the camera which is embedded in the pointing device and estimate the movement of the device. The pose of the cursor can be determined from this result. To process in the real time, we used the low resolution of $288{\times}208$ pixel camera and comer points of the screen were tracked using local optical flow method. The distance from screen and device was calculated from the size of screen in the image. The proposed device has simple configurations, low cost, easy use, and intuitive handhold operation like traditional mice. Moreover it shows reliable performance even in the dark condition.

An Investigation on the Technical Background for Carbon-14 Monitoring in Radioactive Effluents (원자력시설의 Carbon-14 방사성유출물에 대한 감시배경의 조사)

  • Kim, Hee-Geun;Kong, Tae-Young;Jeong, Woo-Tae;Kim, Seok-Tae
    • Journal of Radiation Protection and Research
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    • v.34 no.4
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    • pp.195-200
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    • 2009
  • effluents to the environment. The activity of carbon-14, one of the radioactive effluents, in the environment is already high level and its effect on radiation exposure to the public and the environment is insignificant; thus, NPPs did not perform the carbon-14 monitoring in effluents in the past. By the way, effluents of noble gas and particulate radioactive materials originated from nuclear fuels has been continuously reduced due to both the advancement of manufacturing and integrity technology for nuclear fuels and the improvement of operation methods of NPPs. Futhermore, the portion of dose assessment by tritium and carbon-14 to the public has been relatively increased because the lower limit of detection for low-energy beta sources, such as tritium and carbon-14, is low due to the advancement of radiation detection technology. In this paper, the technical background for carbon-14 monitoring in nuclear facilities was investigated using United States technical reports and papers. This paper also reviews whether carbon-14 monitoring is necessary or not based on the investigated documents.

Development of hybrid shielding system for large-area Compton camera: A Monte Carlo study

  • Kim, Jae Hyeon;Lee, Junyoung;Kim, Young-su;Lee, Hyun Su;Kim, Chan Hyeong
    • Nuclear Engineering and Technology
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    • v.52 no.10
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    • pp.2361-2369
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    • 2020
  • Compton cameras using large scintillators have been developed for high imaging sensitivity. These scintillator-based Compton cameras, however, mainly due to relatively low energy resolution, suffer from undesired background-radiation signals, especially when radioactive materials' activity is very low or their location is far from the Compton camera. To alleviate this problem for a large-size Compton camera, in the present study, a hybrid-type shielding system was designed that combines an active shield with a veto detector and a passive shield that surrounds the active shield. Then, the performance of the hybrid shielding system was predicted, by Monte Carlo radiation transport simulation using Geant4, in terms of minimum detectable activity (MDA), signal-to-noise ratio (SNR), and image resolution. Our simulation results show that, for the most cases, the hybrid shielding system significantly improves the performance of the large-size Compton camera. For the cases investigated in the present study, the use of the shielding system decreased the MDA by about 1.4, 1.6, and 1.3 times, increased the SNR by 1.2-1.9, 1.1-1.7, and 1.3-2.1 times, and improved the image resolution (i.e., reduced the FWHM) by 7-8, 1-6, and 3-5% for 137Cs, 60Co, and 131I point source located at 1-5 m from the imaging system, respectively.

A Traffic Model based on the Differentiated Service Routing Protocol (차별화된 서비스제공을 위한 트래픽 모델)

  • 인치형
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.10B
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    • pp.947-956
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    • 2003
  • The current IP Routing Protocolspacket networks also need to provide the network QoS based of DiffServ, RSVP, MPLStraffic model which is standardized as IETF reference model for NGN. The first topic of this paper is to propose Traffic-Balanced Routing Protocol(TBRP) to process existing best effort traffic. TBRP will process low priority interactive data and background data which is not sensitive to dealy. Secondly Hierarchical Traffic-Traffic-Scheduling Routing Protocol(HTSRP) is also proposed. HTSRP is the hierarchical routing algorithm for backbone and access networkin case of fixed-wireless convergence network. Finally, HTSRP_Q is proposed to meet the QoS requirement when user want interactive or streaming packet service. This protocol will maximize the usage of resources of access layer based on the QoS parameters and process delay-sensitive traffic. Service classes are categorized into 5 types by the user request, such as conversational, streaming, high priority interactive, low priority interactive, and background class. It could be processed efficiently by the routing protocolstraffic model proposed in this paper. The proposed routing protocolstraffic model provides the increase of efficiency and stability of the next generation network thanks to the routing according to the characteristic of the specialized service categories.

Efficiency Low-Power Signal Processing for Multi-Channel LiDAR Sensor-Based Vehicle Detection Platform (멀티채널 LiDAR 센서 기반 차량 검출 플랫폼을 위한 효율적인 저전력 신호처리 기법)

  • Chong, Taewon;Park, Daejin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.7
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    • pp.977-985
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    • 2021
  • The LiDAR sensor is attracting attention as a key sensor for autonomous driving vehicle. LiDAR sensor provides measured three-dimensional lengths within range using LASER. However, as much data is provided to the external system, it is difficult to process such data in an external system or processor of the vehicle. To resolve these issues, we develop integrated processing system for LiDAR sensor. The system is configured that client receives data from LiDAR sensor and processes data, server gathers data from clients and transmits integrated data in real-time. The test was carried out to ensure real-time processing of the system by changing the data acquisition, processing method and process driving method of process. As a result of the experiment, when receiving data from four LiDAR sensors, client and server process was operated using background or multi-core processing, the system response time of each client was about 13.2 ms and the server was about 12.6 ms.

Examining the Predictors of Turnover Behavior in Newly Employed Certified Nurse Aides: A Prospective Cohort Study

  • Hsiao-Ching Chen;Jiun-Yi Wang;Ya-Chen Lee ;Shang-Yu Yang
    • Safety and Health at Work
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    • v.14 no.2
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    • pp.185-192
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    • 2023
  • Background: The turnover rate of nurse aides in Taiwan is high. However, the predictors of turnover behavior in the newly employed are still unclear. Objective: To examine the predictors of turnover behavior in newly employed licensed nurse aides. Methods: A longitudinal study design was used and subjects were newly employed certified nurse aides from a nurse aid training association in Taiwan. A total of five questionnaire surveys were conducted. The questionnaire was mainly used to collect information on turnover behavior, personal socioeconomic background, workplace psychosocial hazards, worker health hazards, and musculoskeletal disorders. Results: A total of 300 participants were recruited in the study. Cox regression analysis results showed that short working experience (hazard ratio [HR] = 0.21, p < 0.01), work as non-home nurse aides (HR = 0.58, p = 0.01), low monthly salary (HR = 0.68, p < 0.01), high work mental load (HR = 1.01, p = 0.01), low workplace justice (HR = 0.97, p < 0.01), high workplace violence (HR = 1.60, p < 0.01), high burnout (HR = 1.01, p = 0.04), poor mental health (HR = 1.06, p = 0.04), and high total number of musculoskeletal disorder sites (HR = 1.08, p = 0.01) contribute to a higher risk of turnover. Conclusion: The results indicated that employment period, work as a home nurse aide, monthly salary, work mental load, workplace justice, workplace violence, work-related burnout, mental health, and total number of musculoskeletal disorder sites are predictors of turnover behavior in newly employed certified nurse aides.

Development of Rainfed-adapted, Fertilizer-efficient Temperate Rice Varieties by Pup1 Introgression

  • Ian Paul Navea;Jae-Hyuk Han;Na-Hyun Shin;Yeong-Ju Lee;Joong Hyoun Chin
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.272-272
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    • 2022
  • Water and phosphorus (P) fertilizer are two of the most critical inputs in rice cultivation. Under climate change scenarios and urbanization, irrigation and fertilizer are becoming limiting factors often leading to significant decrease in yield whenever supplied scarcely. It has been shown that the Pup1 QTL confers tolerance to P starvation and improved early-stage root vigor in indica rice grown in the tropics. However, whether the QTL works in japonica rice genetic background grown in temperate regions remains to be elucidated. Here, we have introgressed the Pup1 QTL into three temperate rice varieties MS11, TR22183, and Dasan using marker-assisted backcrossing and next generation sequencing. The selected lines all harbored the full Pup1 QTL with recurrent parent genome recovery rates ranging from 66.5% to 99.8%. Evaluation of the introgression rice lines grown in South Korea under low inputs of P and water revealed early vegetative growth advantage relative to that of the recurrent parents. Under rainfed condition, Pup1 introgression lines had yield advantage ranging from 7.2 to 19.9% and 24 to 26% in P non-supplied soil and P-supplied soil, respectively compared to that of the recurrent parents suggesting that Pup1 confers enhanced yield under low P and water inputs in temperate rice genetic background grown in temperate climate. In terms of early vegetative growth, temperate Pup1 introgression lines showed a similar trend on the extent to which Pup1 promotes yield advantage in temperate rice in comparison with indica control Pup1 introgression line IR64-Pup1.

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Empirical Analysis of Supplier Induced Demand in Korea: Distinction between Induced Demand Effect and Availability Effect (우리나라 의원에서의 공급자 유인수요 실증분석: 유인수요 효과와 가용성 효과의 구분)

  • Yeo, Ji-Young;Jeong, Hyoung-Sun
    • Health Policy and Management
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    • v.25 no.1
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    • pp.53-62
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    • 2015
  • Background: Supplier induced demand (SID) indicates the case when doctors increase the demand of the patients, following their (physicians') own best interests rather than patients'. This may occur when asymmetry of information exists between suppliers and consumers. This study aims to confirm whether SID exists in the Korean setting, particularly by dividing SID into both 'induced demand effect' and 'availability effect.' Methods: Induced demand effect and availability effect are differentiated following Carlsen & Grytten's theoretical frame which divides doctor density regions into high and low ones. Results: Positive correlation between doctors' density and utilization of their services was found, which could be interpreted as 'availability effect.' Conclusion: The result suggests that additional medical use for additional doctor, particularly in the area of low doctor density, can be interpreted to occur to meet the basic medical need of the people rather than as a result of unnecessary induced demand. It is important to make more medical doctors provided and to distribute them appropriately across the region in such a country like Korea where doctor's density is relatively low.

Immediate Effects of Low-Dye Taping on the Ankle Motion and Ground Reaction Forces in the Pronated Rear-Foot During Gait

  • Kim, Sung-shin;Chung, Jae-yeop
    • Physical Therapy Korea
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    • v.23 no.1
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    • pp.72-79
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    • 2016
  • Background: Increased foot pronation causes biomedchanical changes at the lower limbs, which may result in musculoskeletal injuries at the proximal joints. Pronation rear-foot leads to plantar fasciitis, Achilles tendonitis, and posterior tibial tendonitis pathologically. According to the recent meta-analysis, They showed that therapeutic adhesive taping is more effective than foot orthoses and motion control footwear, low-Dye (LD) taping has become the most popular method used by physiotherapists. Objects: The purpose of this study was to determine the immediate effects of LD taping results in different ankle motion and ground reaction force (GRF) as before and after applied LD taping on pronated rear-foot during gait. Methods: Twenty-four participants were recruited for this study. The gait data were recorded using an 8-camera motion capture system and two force platforms. At first, the experiments were carried out that participants walked barefoot without LD taping. And then they walked both feet was applied LD taping. Results: The ankle inversion minimum was significantly greater after LD taping than before LD taping (p=.04); however, in the GRF, there were no significant differences in the inversion maximum or total motion of the stance phase (p=.33, p=.07), or in the vertical (p=.33), posterior (p=.22), and lateral (p=.14) peak forces. Conclusion: The application of taping to pronation rear-foot assists in increased ankle inversion.

A building roof detection method using snake model in high resolution satellite imagery

  • Ye Chul-Soo;Lee Sun-Gu;Kim Yongseung;Paik Hongyul
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.241-244
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    • 2005
  • Many building detection methods mainly rely on line segments extracted from aerial or satellite imagery. Building detection methods based on line segments, however, are difficult to succeed in high resolution satellite imagery such as IKONOS imagery, for most buildings in IKONOS imagery have small size of roofs with low contrast between roof and background. In this paper, we propose an efficient method to extract line segments and group them at the same time. First, edge preserving filtering is applied to the imagery to remove the noise. Second, we segment the imagery by watershed method, which collects the pixels with similar intensities to obtain homogeneous region. The boundaries of homogeneous region are not completely coincident with roof boundaries due to low contrast in the vicinity of the roof boundaries. Finally, to resolve this problem, we set up snake model with segmented region boundaries as initial snake's positions. We used a greedy algorithm to fit a snake to roof boundary. Experimental results show our method can obtain more .correct roof boundary with small size and low contrast from IKONOS imagery. Snake algorithm, building roof detection, watershed segmentation, edge-preserving filtering

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