• Title/Summary/Keyword: Real - time

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An Adaptive ROI Decision for Real-time Performance in an Autonomous Driving Perception Module (자율주행 인지 모듈의 실시간 성능을 위한 적응형 관심 영역 판단)

  • Lee, Ayoung;Lee, Hojoon;Yi, Kyongsu
    • Journal of Auto-vehicle Safety Association
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    • v.14 no.2
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    • pp.20-25
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    • 2022
  • This paper represents an adaptive Region of Interest (ROI) decision for real-time performance in an autonomous driving perception module. Since the whole automated driving system consists of numerous modules and subdivisions of module occur, it is necessary to consider the characteristics, complexity, and limitations of each module. Furthermore, Light Detection And Ranging (Lidar) sensors require a considerable amount of time. In view of these limitations, division of submodule is inevitable to represent high real-time performance for stable system. This paper proposes ROI to reduce the number of data respect to computation time. ROI is set by a road's design speed and the corresponding ROI is applied differently to each vehicle considering its speed. The simulation model is constructed by ROS, and overall data analysis is conducted by Matlab. The algorithm is validated using real-time driving data in urban environment, and the result shows that ROI provides low computational costs.

Development of a real-time gamma camera for high radiation fields

  • Minju Lee;Yoonhee Jung;Sang-Han Lee
    • Nuclear Engineering and Technology
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    • v.56 no.1
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    • pp.56-63
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    • 2024
  • In high radiation fields, gamma cameras suffer from pulse pile-up, resulting in poor energy resolution, count losses, and image distortion. To overcome this problem, various methods have been introduced to reduce the size of the aperture or pixel, reject the pile-up events, and correct the pile-up events, but these technologies have limitations in terms of mechanical design and real-time processing. The purpose of this study is to develop a real-time gamma camera to evaluate the radioactive contamination in high radiation fields. The gamma camera is composed of a pinhole collimator, NaI(Tl) scintillator, position sensitive photomultiplier (PSPMT), signal processing board, and data acquisition (DAQ). The pulse pile-up is corrected in real-time with a field programmable gate array (FPGA) using the start time correction (STC) method. The STC method corrects the amplitude of the pile-up event by correcting the time at the start point of the pile-up event. The performance of the gamma camera was evaluated using a high dose rate 137Cs source. For pulse pile-up ratios (PPRs) of 0.45 and 0.30, the energy resolution improved by 61.5 and 20.3%, respectively. In addition, the image artifacts in the 137Cs radioisotope image due to pile-up were reduced.

Analysis of Appropriate Outpatient Consultation Time for Clinical Departments (진료과별 적정 외래 진료시간에 관한 연구)

  • Lee, Chan Hee;Lim, Hyunsun;Kim, Youngnam;Park, Ai Hee;Park, Eun-Cheol;Kang, Jung-Gu
    • Health Policy and Management
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    • v.24 no.3
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    • pp.254-260
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    • 2014
  • Background: The purpose of this study is to assume appropriate outpatient consultation time for each clinical department on the basis of measured outpatient consultation time and satisfaction of outpatient. Methods: We surveyed the feeling and satisfactory outpatient consultation time, satisfaction, revisiting intention and recommendation to others to 1,105 patients of single general hospital in Gyeonggi-do and measured their real outpatient consultation time from October 28 to November 27 in 2013. On the basis of satisfaction, we estimated appropriate outpatient consultation time through area under the receiver operating characteristic curve in logistic regression model. Results: Feeling outpatient consultation time was 5.1 minutess, satisfactory outpatient consultation time which was suggested by patient was 6.3 minutes, and real outpatient consultation time was 4.2 minutes. Department which had longest real outpatient consultation time was infection (7 minutes) and department which had longest satisfactory outpatient consultation time was neurology (9.4 minutes). From the univariate and the multiple linear regression analysis, real outpatient consultation time was longer in pulmonology patient, new patient and afternoon patient, satisfactory outpatient consultation time was longer in infection, neurology, neuropsychiatry, neurosurgery, and rehabilitation patient. Appropriate real outpatient consultation time was suggested as 5.6 minutes which differentiated high and low satisfied patient group. However, we could not assume appropriate outpatient consultation time for each clinical department because the number of patient who had bad satisfaction was too low. Conclusion: To improve patient's satisfaction, we hope outpatient reservation system is operated as each patient's outpatient consultation time is at least 5.6 minutes.

An Extension to Time-out Facility in C Language for Embedded Real-Time Programming (내장 실시간 프로그래밍을 위한 C 언어의 타임아웃 기능의 확장)

  • Lee, Sheen;Yang, Seung-Min
    • Journal of KIISE:Computing Practices and Letters
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    • v.8 no.4
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    • pp.423-429
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    • 2002
  • Time-out is one of the basic but important functions in real-time programming. However, the C language used commonly in the embedded real-time systems doesn't support this capability. For this capability, there have been numerous studies on language extension and/or special purpose real-time kernel (or engine). Those require preprocessor or new kernel support. In this paper, we propose a time-out facility supported by a library and some macro functions with a minimum dependency on operating systems. Furthermore, we also provide a structured _within statement, a macro function which makes programming easy. We have implemented this for the LINUX and the DOS environment, and for the POSIX multithread environment as well.

Design of Network-based Real-time Connection Traceback System with Connection Redirection Technology

  • Choi, Yang-Sec;Kim, Hwan-Guk;Seo, Dong-Il;Lee, Sang-Ho
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.2101-2105
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    • 2003
  • Recently the number of Internet users has very sharply increased, and the number of intrusions has also increased very much. Consequently, security products are being developed and adapted to prevent systems and networks from being hacked and intruded. Even if security products are adapted, however, hackers can still attack a system and get a special authorization because the security products cannot prevent a system and network from every instance of hacking and intrusion. Therefore, the researchers have focused on an active hacking prevention method, and they have tried to develop a traceback system that can find the real location of an attacker. At present, however, because of the characteristics of Internet - diversity, anonymity - the real-time traceback is very difficult. To over-come this problem the Network-based Real-Time Connection Traceback System (NRCTS) was proposed. But there is a security problem that the victim system can be hacked during the traceback. So, in this paper, we propose modified NRCTS with connection redirection technique. We call this traceback system as Connection Redirected Network-based Real-Time Connection Traceback System (CR-NRCTS).

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Inductance Estimation of Permanent Magnet Type Transverse Flux Rotating Motor Using Dynamic-Simulation (Dynamic-Simulation을 통한 영구자석형 횡자속 회전기의 인덕턴스 추정)

  • Kim, Kwang-Woon;Kim, Ji-Won;Jung, Yeon-Ho;Lee, Ji-Young;Kang, Do-Hyun;Chang, Jung-Hwan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.4
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    • pp.722-727
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    • 2010
  • This paper presents Dynamic-Simulation to estimate the inductance of a permanent magnet type transverse flux rotating motor by applying the real-time parameter estimation theory. As transverse flux rotating motor has the complex structure, it can be happen to some errors between real value and designed one with respect to the inductance. To reduce this kinds of errors, the real-time parameter estimation theory was applied to dynamic-simulation. And then, By comparing the estimated inductance and designed one, it is realized that the real-time parameter estimation theory can be applied in the permanent magnet type transverse flux rotating motor.

Development of Real-Time Inspection System for Foods Packaging Film using MMX Technology (MMX기술을 이용한 식품 포장용 투명필름의 실시간 검사시스템 개발)

  • Yoo, Joo-Hyun;Lee, Jae-Hyeok
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.156-158
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    • 2004
  • Film printing companies have many problems during a printing process. Most of all, even an insect or dirt stick to the transparent film may cause severe errors until the end of printing job, which means big economic damage to the company. To prevent some insect-dots or dirt-dots, we have to Inspect the total area of film. However, it is very difficult to inspect the film in real-time due to the high-speed of printing that usually more than 150 m/min. A hardware based approach, for example DSP-based approach can be the one of solution candidates, but the total cost and the complexity increases the very high-level. In this paper, we suggest a software based approach, using MMX technology, to inspect the film in real-time. By Many real-plant experiments, we can see the suggest approach is applicable for the inspection of food packaging film in real-time.

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A Specifying method for Real-Time Software Requirement

  • Kim, Jung-Sool;Lee, chang-soon
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 1998.10a
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    • pp.655-662
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    • 1998
  • This paper is on the anlaysis for real-time software requirement . This method can be used for TNPIN(Timed Numerical Petri Net) as a easy communication means with a real-users. It is based on the RTTL(Real Time Temporal Logic) for correctness fo the system. TNPN is used to represent a behavior specification language, the validity of specified behaviors in TNPN is expressed in RTTL , and analyzed through the reachability graph. Thus , the requirement of between user and system is satisfied. By the example of shared track, the validity of the property of real-time (safetiness, responsiveness, liveness, priority) is verified. Also, this framework is give to connection with a object natually.

Tractive Force Estimation in Real-time Using Brake Gain Adaptation (브레이크 게인 적응기법을 이용한 종방향 타이어 힘의 실시간 추정)

  • ;;Karl Hedrick
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.3
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    • pp.214-219
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    • 2003
  • This paper includes real-time tractive force estimation method using standard vehicle sensors such as wheel speed, brake pressure, throttle position, engine speed, and transmission carrier speed sensor. Engine map, torque converter lookup table, shaft torque observer, and brake gain adaptation method are used to estimate the tractive force. To verify this estimator, measurement which uses strain-based brake torque sensor and estimation results are presented. All results was performed using a real vehicle in a real-time.

The Application of Real Time Digital Simulator for Analyzing the Performance of Power System Stabilizer(PSS) (전력계통 안정화장치(PSS)의 성능 분석을 위한 실시간 디지털 시뮬레이터 응용)

  • Hur, Jin;Kim, Dong-Joon;Moon, Young-Hwan;Shin, Jeong-Hoon;Kim, Tae-Kyun
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.49 no.9
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    • pp.459-466
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    • 2000
  • The performance of a commercialized power system stabilizer (PWX-600) for a single hydro-turbine generator and infinite bus system has been investigated using Real Time Digital Simulator (RTDS) in this paper. The test system was composed of RTDS, three phase voltage/current amplifier and the PSS. The test scheme provided a very efficient way to verify the design and control performance of a PSS to be applied to real power system. The scheme can also be applied to verify in real time the performance of hardware and software of power system controllers for FACTS and protective relays effectively.

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