• Title/Summary/Keyword: operational safety

Search Result 964, Processing Time 0.024 seconds

Research for the Method of Design Consistency Evaluation Using Individual Driving Behavior (개별차량의 주행행태를 이용한 설계일관성 평가 방법에 관한 연구)

  • Son, Young Tae;Kim, Chul Ki
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.28 no.6D
    • /
    • pp.767-774
    • /
    • 2008
  • This study has been developed the way that evaluates the road safety using the speed of individual vehicles at curve sections in 2-lane rural highways. For this study, we developed variation of operational speed for the individual vehicle using the speed of vehicles in 96points of selected roads. Drawing out of variation of operational speed for the individual vehicle, estimation models for speed variation of individual vehicles considering horizontal alignments and vertical alignments of the roads have been developed. These models presents the way to evaluate road safety out of the operational speed and acceleration of individual vehicles. Considering safety and based on the results of these study above, some regular spots are ranked by "good", "fair", "bad". The results that this study showed in this paper could be useful to derive some particular spots that needs to be improve in terms of safety.

A Study on the Risk based RAMS Assessment for Railway Rolling Stock Systems (철도차량시스템의 위험기반 RAMS 평가에 관한 연구)

  • Park, Mun-Gyu;Han, Seong-Ho
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.64 no.4
    • /
    • pp.220-230
    • /
    • 2015
  • Rolling stock RAMS is a field of engineering which integrates reliability, availability, maintainability and safety (RAMS) characteristics into an inherent product design property through rolling stock system engineering process. It is implemented to achieve operational objectives successfully, and recently the RAMS has become a rapidly growing engineering discipline because it has a great potential to ensure safety and improve cost effectiveness. However, the Korean rolling stock industry has not yet implemented RAMS management in the rolling stock engineering process, despite the issue having been addressed since the introduction of the KTX. Thus, this paper discusses the processes, methods and techniques for RAMS assessment in three parts. Firstly, it outlines a process of the overall RAMS performance assessment for achieving technical RAMS design criteria. Secondly, it discusses a process for assessing the operational RAM and allocating the RAM. This paper also proposes a model for assessing safety-based risk management, which includes five analytic techniques for identifying the causes and consequences of a system failure. Finally, a case example is provided for the risk assessment of the pneumatic braking device.

Automated Surgical Planning System for Spinal Fusion Surgery with Three-Dimensional Pedicle Model (척추 융합 수술을 위한 삼차원 척추경 모델을 이용한 자동 수술 계획 시스템)

  • Lee, Jong-Won;Kim, Sung-Min;Kim, Young-Soo;Chung, Wan-Kyun
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.17 no.8
    • /
    • pp.807-813
    • /
    • 2011
  • High precision of planning in the preoperative phase can contribute to increase operational safety during computer-aided spinal fusion surgery, which requires extreme caution on the part of the surgeon, due to the complexity and delicacy of the procedure. In this paper, an advanced preoperative planning framework for spinal fusion is presented. The framework is based on spinal pedicle data obtained from CT (Computed Tomography) images, and provides optimal insertion trajectories and pedicle screw sizes. The proposed approach begins with safety margin estimation for each potential insertion trajectory that passes through the pedicle volume, followed by procedures to collect a set of insertion trajectories that satisfy operation safety objectives. The radius of a pedicle screw was chosen as 70% of the pedicle radius. This framework has been tested on 68 spinal pedicles of 8 patients requiring spinal fusion. It was successfully applied, resulting in an average success rate of 100% and a final safety margin of $2.44{\pm}0.51mm$.

Validation of Availability, Maintainability and Safety for Subway Elevating Equipment (도시철도 승강설비의 가용성, 유지보수성 및 안전성 입증)

  • Lee, Hwan-Deok;Jung, Won
    • Journal of Applied Reliability
    • /
    • v.16 no.4
    • /
    • pp.272-279
    • /
    • 2016
  • Purpose: In order to fulfill the RAMS (Reliability Availability Maintainability and Safety) requirements in Korean railway systems, specific target metrics should be measured and met the requirements when ordering a new system. This paper presents a procedure to predict and demonstrate the availability, maintainability and safety of subway elevators, escalators and PSD (platform screen doors) systems. Methods: The system manufacturer predicts availability and maintainability with lab and field tested data. After installation, availability and maintainability are demonstrated based on the actual operational data. The data was collected from the FRACAS (Failure Report and Corrective Action System). Results: Methods and process of assessing and analyzing the availability, maintainability and safety are presented for elevating services and PSD systems. The data obtained through the actual operation of the equipment is analyzed and maintained to predict the RAMS based on the component and system level failure data acquired. Conclusion: This study presented an application using IEC 62278 and operational data which can be used in the design and development stage to achieve the RAMS target value of the subway elevators, escalators and PSD systems.

A Model of Operational Situation Analysis with Functional Safety for ASIL Determination (ASIL 결정을 위한 기능안전 운전상황 분석 모형)

  • Baek, Myoung-Sig;Jang, Hyeon Ae;Kwon, Hyuck Moo
    • Journal of the Korean Society of Safety
    • /
    • v.29 no.4
    • /
    • pp.160-167
    • /
    • 2014
  • To determine a proper ASIL for each hazardous event with a proper safety goal, the right classes should first be determined for the three properties of the hazardous event; (i) severity of harm from the resultant accident, (ii) exposure to the relevant operational situation, and (iii) controllability to avoid the induced risks. ASIL can be clearly determined with right classes of these three properties. But no specific methodologies or processes for their classification can be found in ISO 26262, except only a rough guideline with a simplified set of illustrative tables. In this paper, we try to present a systematic model for classifying the three properties of the hazardous event and suggest a refined procedure of ASIL determination. The proposed model provides a specific method to get a more objective ASIL compared with that in the standard. Scrutinizing the current methodology, we develop a refined method and also provide an illustrative example.

A Study on Class Loading in Java Virtual Machine (자바 가상 머신에서 클래스 로딩에 관한 연구)

  • 김기태;이갑래;유원희
    • The Journal of the Korea Contents Association
    • /
    • v.3 no.2
    • /
    • pp.39-45
    • /
    • 2003
  • Dynamic dan loading and class linking of Java is a poweful mechanism. Many other system also support some form of dynamic loading and linking, but lazy loading, type-safe linkage, user-definable class loading policy, and multiple namespaces are important features of Java The ue U dan loading is assured of type safety. The security of Java greatly depends on type safety. In JVM, type safety mechanism is very difficult and access of accuracy is not dear, so type safety problems were raised. In paper, n analysis simple Java code and present a diagram graph and an operational semantics for dynamic class loading and type safety.

  • PDF

Safety Management for MR-Guided Interventions

  • Cherkashin, Mikhail;Berezina, Natalia;Serov, Alexey;Fedorov, Artem;Andreev, Georgy;Kuplevatsky, Vladymir
    • Investigative Magnetic Resonance Imaging
    • /
    • v.20 no.3
    • /
    • pp.152-157
    • /
    • 2016
  • Purpose: Operating room management is the serious and complex task for hospital managers and the common approach is to develop relevant standard operational procedures. From patient and staff safety perspective, operating room management should be well-studied and hospital should identify and address any potential risks. Simultaneous usage of different imaging and less-invasive treatment technologies demands strong management control. Materials and Methods: We have formed the multidisciplinary expert panel (surgeons, anesthesiologists, radiologists, healthcare managers etc.) for hybrid theater management standard operational procedure development. On the first stage the general concept of hybrid room design and patient routing was developed. The second stage included the technical details discussion. For patient safety improvement we modified the Surgical Safety Check-list in accordance with potential MRI-related safety challenges and concerns. Results: WHO Surgical Safety Checklist is a simple and easy-to use tool which includes three blocks of question (grouped by the surgery process). We have developed two additional blocks of questions for the intraoperative magnetic resonance investigation. It is very important to have a special detailed routing with a strong control of ferromagnetic devices and anesthesiology care. Conclusion: High-energy MRI (1.5-3.0T) is characterized by potential influence on patient and staff safety in case of hybrid surgery. It is obvious to have a strong managerial control of ferromagnetic devices and anesthesiology care. Surgical Safety Checklist is the validated tool for improving patient safety. Modification and customization of this check-list potentially provides the opportunity for surgery processes improving.

Availability Measures for Repairable Dynamic Reliability Models (수리 가능한 동적 신뢰도 모델의 가용도 척도)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
    • /
    • v.8 no.5
    • /
    • pp.253-264
    • /
    • 2006
  • This paper is to derive three reliability and eight maintainability measures after organizing total time. I propose inherent availability,.achieved availability and operational availability with the new and useful reliability and maintainability measures above. Especially, inherent availability measure extends the repairable system reliability models.

Evaluation of Software Diagnostics for Secure Operational Environment in Nuclear I&C systems (원전 계측제어 시스템 보안성환경을 위한 진단기능 평가)

  • Yoo, Sung Goo;Seul, Namo
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.53 no.8
    • /
    • pp.107-112
    • /
    • 2016
  • Safety Critical Instrumentation and Control Systems perform those functions to maintain nuclear power plants' parameters within acceptable limits established for a design basis events and anticipated operating occurrence to ensure safety function. Those digitalized systems shall protect inadvertent and non-malicious behavior to ensure the reliable operation of systems, known as a Secure Development and Operational Environment(SDOE). SDOE would be established through managerial and technical controls. The objective of this paper is to evaluate the effectiveness of Cyclic Redundancy Checksum diagnostic, which is one of technical controls for SDOE, that can confirm the integrity of software of I&C systems to establish the secure environment. The results of this assessment would be the practical implementation of design and safety review of nuclear I&C systems.