• Title/Summary/Keyword: Software and system safety

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A Study on the Approach to Achieve Software Quality in Railway (철도소프트웨어 품질향상 방안 고찰)

  • Joung, Eui-Jin;Shin, Kyung-Ho
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.1132-1133
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    • 2006
  • The approach, for ensuring the quality and safety of a railway software can be considered with two points of views seeing from products, and from processes. The process point of view is to validate maturity of the organizations in accordance to the judging processes of organizations, which are specified by CMMI(Capability Maturity Model Integration) or SPICE(Software Process Improvement and Capability dEtermination : ISO/IEC15504). In this paper, we are trying to find approaches to estimate the maturity of manufacturer and assessment organization in the railway system.

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Analysis of Control Element Assembly Withdrawal at Full Power Accident Scenario Using a Hybrid Conservative and BEPU Approach

  • Kajetan Andrzej Rey;Jan Hruskovic;Aya Diab
    • Nuclear Engineering and Technology
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    • v.55 no.10
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    • pp.3787-3800
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    • 2023
  • Reactivity Initiated Accident (RIA) scenarios require special attention using advanced simulation techniques due to their complexity and importance for nuclear power plant (NPP) safety. While the conservative approach has traditionally been used for safety analysis, it may lead to unrealistic results which calls for the use of best estimate plus uncertainty (BEPU) approach, especially with the current advances in computational power which makes the BEPU analysis feasible. In this work an Uncontrolled Control Element Assembly (CEA) Withdrawal at Full Power accident scenario is analyzed using the BEPU approach by loosely coupling the thermal hydraulics best-estimate system code (RELAP5/SCDAPSIM/MOD3.4) to the statistical analysis software (DAKOTA) using a Python interface. Results from the BEPU analysis indicate that a realistic treatment of the accident scenario yields a larger safety margin and is therefore encouraged for accident analysis as it may enable more economic and flexible operation.

Application of AIS in AtoN Wireless Surveillance System

  • Liu, Chang;Liu, Ren-Jie;Shi, Xiao-Fei;Huang, Yao-Liang
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2006.10a
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    • pp.129-133
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    • 2006
  • In China, the traditional method of artificial and periodical cruise is still adopted for the AtoN management, which has brought many disadvantages to the work of the AtoN management, such as non real-time, fallibility, and low efficiency However, with the rapid development of AIS technique, now AIS equipments have been widely installed on ships, and on the other hand China Maritime Safety Administration (abr. China MSA) is carrying out the scheme of AIS base station network in china, based on which the digital AtoN will develop in the future. According to what have been analyzed above, this paper puts forward a design of AtoN wireless surveillance system based on AIS. The system consists of AIS on AtoN, AIS base station and AtoN management center. It can provide such functions as the information gathering, managing of AtoN and the service of navigation assistance. This paper gives the whole design including the work theory, the hardware structure and the software scheme of the system, and finally gives the simulation software of the AtoN management center. The AtoN wireless surveillance system brought forward by this paper will be more efficient with less repair cost and less work of the supervisors. It will bring revolutionary progress in the navigation aids system in China.

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The Design of Fault Tolerant Dual System and Real Time Fault Detection for Countdown Time Generating System

  • Kim, Jeong-Seok;Han, Yoo-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.10
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    • pp.125-133
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    • 2016
  • In this paper, we propose a real-time fault monitoring and dual system design of the countdown time-generating system, which is the main component of the mission control system. The countdown time-generating system produces a countdown signal that is distributed to mission control system devices. The stability of the countdown signal is essential for the main launch-related devices because they perform reserved functions based on the countdown time information received from the countdown time-generating system. Therefore, a reliable and fault-tolerant design is required for the countdown time-generating system. To ensure system reliability, component devices should be redundant and faults should be monitored in real time to manage the device changeover from Active mode to Standby mode upon fault detection. In addition, designing different methods for mode changeover based on fault classification is necessary for appropriate changeover. This study presents a real-time fault monitoring and changeover system, which is based on the dual system design of countdown time-generating devices, as well as experiment on real-time fault monitoring and changeover based on fault inputs.

Policy and Mechanism for Safe Function-level Dynamic Kernel Update (함수 단위 동적 커널 업데이트를 위한 보안 정책 및 기법의 설계)

  • Park, Hyun-Chan;Yoo, Chuck
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.8
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    • pp.808-812
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    • 2008
  • In recent years, the software vulnerability becomes an important problem to the safety in operating system kernel. Many organizations endeavor to publish patches soon after discovery of vulnerability. In spite of the effort, end-system administrators hesitate to apply the patches to their system. The reasons of hesitation are the reboot disruption and the distrust of patches. To solve this problem we propose a dynamic update system for non-updatable kernel, named DUNK. The DUNK provides: 1) a dynamic update mechanism at function-level granularity to overcome the reboot disruption and 2) a safety verification mechanism to overcome the distrust problem, named MAFIA. In this paper, we describe the design of DUNK and detailed algorithm of MAFIA.

Software Development Process of Military Aircraft based on MIL-HDBK-516C (MIL-HDBK-516C 기반의 군용항공기 탑재 소프트웨어 개발 프로세스)

  • Heo, Jin-Gu;Moon, Yong-Ho
    • Journal of Aerospace System Engineering
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    • v.15 no.3
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    • pp.71-78
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    • 2021
  • Since most functions of modern aircraft are controlled by software, software errors are directly related to aircraft safety. The criterion in Chapter 15 of the MIL-HDBK-516C addresses safe development and verification of military aircraft software. As the U.S. Air Force repeatedly experienced non-compliance with Chapter 15 criterion of the MIL-HDBK-516C, it published an Airworthiness Circular (AC-17-01) as a guide to meeting the criterion. In this paper, Chapter 15 of MIL-HDBK-516C, AC-17-01 and the SW Qualification Guideline (DO-178C) as applied by the Federal Aviation Administration are compared and analyzed. For the analysis, a matching ratio formula between the MIL-HDBK-516C criteria specified in AC-17-01 and the DO-178C specified in MIL-HDBK-516C criteria is defined. The sections that satisfy MIL-HDBK-516C criterion are derived when AC-17-01 or DO-178C matches. Based on the analysis results, the aircraft software development process is established and examples of application of Chapter 15 of MIL-HDBK-516C are addressed.

REAL-TIME PERSONAL DOSE MEASUREMENT AND MANAGEMENT SYSTEM RESEARCH IN CHINA

  • Zhang, Z.Y.;Cheng, C.;Liu, Z.S.;Yang, H.T.;Deng, C.M.;Zhang, X.;Guo, Z.J.
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.281-286
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    • 2001
  • The composition and design of a real-time personal dose measurement and management system are described in this paper. Accordingly, some pertinent hardware circuits and software codes including their operation modes have also been presented.

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Comparison of Deep-Learning Algorithms for the Detection of Railroad Pedestrians

  • Fang, Ziyu;Kim, Pyeoungkee
    • Journal of information and communication convergence engineering
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    • v.18 no.1
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    • pp.28-32
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    • 2020
  • Railway transportation is the main land-based transportation in most countries. Accordingly, railway-transportation safety has always been a key issue for many researchers. Railway pedestrian accidents are the main reasons of railway-transportation casualties. In this study, we conduct experiments to determine which of the latest convolutional neural network models and algorithms are appropriate to build pedestrian railroad accident prevention systems. When a drone cruises over a pre-specified path and altitude, the real-time status around the rail is recorded, following which the image information is transmitted back to the server in time. Subsequently, the images are analyzed to determine whether pedestrians are present around the railroads, and a speed-deceleration order is immediately sent to the train driver, resulting in a reduction of the instances of pedestrian railroad accidents. This is the first part of an envisioned drone-based intelligent security system. This system can effectively address the problem of insufficient manual police force.

An Implementation of Image Security System Based on Web (웹기반 화상 감시 시스템의 구현)

  • Park Young-Seak;Cho Pyung-Kee
    • Journal of the Institute of Convergence Signal Processing
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    • v.1 no.1
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    • pp.74-81
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    • 2000
  • In this paper we have developed an image security system based on Internet Web in order to overcome the problem of existing systems that use the dedicated network. The developed system resolves the safety problem of the centralized control model by adapting the distributed control model based on Web, and has the functions of remote control and automatic monitoring for grouped multiple sites on remote Web browser. And the system can operate various computers or operating system because it' s operating software was designed by the concepts of Java Virtual Machine and Virtual Instrument. Also, our system has not need of additional cost for network construction by using Internet and can greatly improve the managemental efficiency of system because the maintenance and publishing of software updates can be performed through Web Server.

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Real Time 1/3 Octave Band Control System for High Intensity Acoustic Chamber (음향 챔버 내부의 1/3 옥타브 스펙트럼 실시간 제어 시스템)

  • Kim, Young-Key;Kim, Hong-Bae;Moon, Sang-Mu;Woo, Sung-Hyun;Lee, Sang-Seol
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.881-885
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    • 2002
  • This paper presents the performance and the algorithm of a 1/3-octave band spectrum control system. The system is developed to provide various spectrums in a high intensity acoustic chamber. The required spectrum, which usually comes from launch vehicle company, starts from 25Hz band and ends 10kHz band. Automatic spectrum control system is preferred since the system requires short settling time to guarantee the safety of test objects and to reduce the amount of operating gas. The developed system adapted a PCI data-acquisition/signal-generation board installed in a personal computer to implement whole control logic. The control software used three cascade digital Butterworth filters using software. The filers are designed following ANSI S1.11 standard to implement 1/3 octave band filter bank. The graphical user interface of the system guides the user to follow standard operation procedure. The averaged control spectrum showed less than 0.05 dB in every running 1/3-octave band.

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