Water safety assessment and spatio-temporal changes in Dongting Lake, China on the basis of water regime during 1980–2014

2019 ◽  
Vol 11 (3) ◽  
pp. 877-890
Author(s):  
Rongrong Wan ◽  
Peng Wang ◽  
Xue Dai ◽  
Zheng He
Keyword(s):  
Lake Water ◽  
Safety Assessment ◽  
Water Regime ◽  
Water Security ◽  
Assessment Method ◽  
Dongting Lake ◽  
Water Safety ◽  
Safety Level ◽  
Regime Changes ◽  
Spatio Temporal

Abstract The drastic changes in water regime are of great importance for maintaining water security in lakes with violent seasonal fluctuations. Based on hydrological data of Dongting Lake, the second largest freshwater lake in China, during 1980–2014, a set of water safety assessment methods suitable for seasonal lakes was constructed. Results demonstrated the following. (1) The year 2003 was a major time point for changes in water regime in Dongting Lake between 1980 and 2014. (2) The water regime changes in different parts of Dongting Lake exhibited certain similarities in periodicity and overall change trends. Among them, South Dongting Lake presented the best water security status, followed by East Dongting Lake and West Dongting Lake. (3) Compared with 1980–2002, the complexity of the water safety level change in East Dongting Lake increased in 2003–2014, as manifested in the tendency of the distribution of water safety levels to change sharply. (4) The influence of dry years on the water safety of Dongting Lake was greater than that of rainy years. The multi-time, multi-scale and multi-target lake water safety assessment method based on water regimes provides new ideas and methods for global research on seasonal lake water safety.

Composition of Safety and Cyber Security Analysis Techniques and Tools for NPP I&C System Assessment

2020 ◽  
pp. 204-220
Author(s):  
Ievgen Babeshko ◽  
Kostiantyn Leontiiev
Keyword(s):  
Cyber Security ◽  
Nuclear Power ◽  
Safety Assessment ◽  
Security Analysis ◽  
Assessment Method ◽  
Assessment Methods ◽  
Assessment Process ◽  
Safety Level ◽  
Methods And Techniques ◽  
And Control

Safety assessment of nuclear power plant instrumentation and control systems (NPP I&Cs) is a complicated and resource-consuming process that is required to be done so as to ensure the required safety level and comply to normative regulations. A lot of work has been performed in the field of application of different assessment methods and techniques, modifying them, and using their combinations so as to provide a unified approach in comprehensive safety assessment. Performed research has shown that there are still challenges to overcome, including rationale and choice of the safety assessment method, verification of assessment results, choosing and applying techniques that support safety assessment process, especially in the nuclear field. This chapter presents a developed framework that aggregates the most appropriate safety assessment methods typically used for NPP I&Cs.

scholarly journals Safety Assessment of Casting Workshop by Cloud Model and Cause and Effect–LOPA to Protect Employee Health

2020 ◽  
Vol 17 (7) ◽  
pp. 2555 ◽  
Author(s):  
Qingwei Xu ◽  
Kaili Xu ◽  
Fang Zhou
Keyword(s):  
Safety Assessment ◽  
Cloud Model ◽  
Least Square Method ◽  
Assessment Method ◽  
Employee Health ◽  
Least Square ◽  
Entropy Weight ◽  
Safety Level ◽  
Cause And Effect ◽  
Assessment Approach

Safety assessment of a casting workshop will provide a clearer understanding of the important safety level required for a foundry. The main purpose of this study was to construct a composite safety assessment method to protect employee health using the cloud model and cause and effect–Layer of Protection Analysis (LOPA). In this study, the weights of evaluation indicators were determined using the subjective analytic hierarchy process and objective entropy weight method respectively. Then, to obtain the preference coefficient of the integrated weight more precisely, a new algorithm was proposed based on the least square method. Next, the safety level of the casting workshop was presented based on the qualitative and quantitative analysis of the cloud model, which realized the uncertainty conversion between qualitative concepts and their corresponding quantitative values, as well as taking the fuzziness and randomness into account; the validity of cloud model evaluation was validated by grey relational analysis. In addition, cause and effect was used to proactively identify factors that may lead to accidents. LOPA was used to correlate corresponding safety measures to the identified risk factors. 6 causes and 19 sub-causes that may contribute to accidents were identified, and 18 potential remedies, or independent protection layers (IPLs), were described as ways to protect employee health in foundry operations. A mechanical manufacturing business in Hunan, China was considered as a case study to demonstrate the applicability and benefits of the proposed safety assessment approach.

scholarly journals POST-FIRE SAFETY OF CONCRETE COLUMNS, An engineering-oriented reliability-based assessment tool

2016 ◽  
Author(s):  
Ruben Van Coile ◽  
Robby Caspeele ◽  
Luc Taerwe
Keyword(s):  
Safety Assessment ◽  
Assessment Tool ◽  
Physical Stability ◽  
Concrete Columns ◽  
Reinforce Concrete ◽  
Assessment Method ◽  
Safety Level ◽  
Concrete Members ◽  
Fire Use ◽  
In Fire

<p>Concrete insulation properties and chemo-physical stability up to 400-500°C generally prevents concrete structures from collapsing in fire. Consequently, the safety assessment of reinforced concrete members – and specifically columns – is a must past any severe fire. This post-fire assessment should be based on reliability considerations, as many uncertainties are associated with both the fire evolution and the residual mechanical properties of the materials. The reliability considerations should clarify whether the column has an adequate safety level for its intended post-fire use. An easy-to-use reliability-based assessment method is presented in this paper to determine the bearing capacity of a reinforce concrete column after a fire, and the safety performance of the method is investigated. The proposed method is shown to be at the same time easy to use and very reliable.</p>

NPP I&C Safety Assessment by Aggregation of Formal Techniques

2018 ◽  
Author(s):  
Eugene Babeshko ◽  
Vyacheslav Kharchenko ◽  
Kostiantyn Leontiiev ◽  
Oleg Odarushchenko ◽  
Oleksiy Strjuk
Keyword(s):  
Nuclear Power ◽  
Safety Assessment ◽  
Power Plants ◽  
Failure Modes ◽  
Assessment Method ◽  
Assessment Methods ◽  
Assessment Process ◽  
Software Safety ◽  
Safety Level ◽  
Normative Documents

Safety assessment of nuclear power plant instrumentation and control systems (NPP I&Cs) is a complicated and resource consuming process that is required be done so as to ensure the required safety level and comply to normative regulations. A lot of work have been performed in the field of application of different assessment methods and techniques, modifying them and using their combinations so as to provide unified approach in comprehensive safety assessment. Anyway, performed research have shown there are still challenges to overcome, including rationale and choice of the safety assessment method, verification of assessment results, choosing and applying techniques that support safety assessment process, especially in the nuclear field. In our work we present developed framework that aggregates the most appropriate safety assessment methods typically used for NPP I&Cs. Key features that this framework provides are the formal descriptions of all required input information for every safety assessment method, possible data flows between methods, possible output information for every method. Such representation allows to obtain possible paths required to get necessary indicators, analyze the possibility to verify them by application of different methods that provide same indicators etc. During safety assessment of NPP I&Cs it is very important to address software due to its crucial role in I&C safety assurance. Relevant standards like IEC 60880 [1] and IEC 62138 [2] provide requirements for software related activities and supporting processes in the software safety lifecycle of computer-based I&C systems of nuclear power plants performing functions of safety category A, B and C, as defined by IEC 61226 [3]. Requirements and frameworks provided by IEC 60880 and IEC 62138 for the nuclear application sector correspond to IEC 61508, part 3 [4]. These standards define several types of safety related software and specify particular requirements for each software type. So as to verify software and confirm correspondence to required safety level, different techniques are suggested in normative documents. We share our experience obtained during software failure modes and effect analysis (software FMEA) and software fault insertion (software FIT) processes into FPGA-based platform, NPP I&C systems based on that platform, and RPCT, integrated development environment used by RPC Radiy and end users to design user application logic, specify hardware configuration etc. We apply software FIT to outputs of RPCT, considering source code, configuration files and firmware files. Finally, we provide a case study of application the developed safety assessment framework and software FMEA/FIT practices during practical assessment of FPGA-based NPP I&C system.

A Novel Safety Assessment Method based on Fault Dependent Matrix

2019 ◽  
Vol 15 (9) ◽  
pp. 2392 ◽  
Author(s):  
Dong Haiyong ◽  
Gu Qingfan ◽  
Wang Guoqing ◽  
Zhai Zhengjun ◽  
Lu Yanhong
Keyword(s):  
Safety Assessment ◽  
Assessment Method

scholarly journals Deformation Inspection and Safety Assessment Method of Buried Flexible Pipeline in Service

2021 ◽  
Vol 1043 (4) ◽  
pp. 042043
Author(s):  
Zhu Xinmin ◽  
Feng Shaokong ◽  
Huang Tao ◽  
Shang Feng ◽  
Yang Lufei
Keyword(s):  
Safety Assessment ◽  
Assessment Method

An Online Quantified Safety Assessment Method for Train Service State Based on Safety Region Estimation and Hybrid Intelligence Technologies

2015 ◽  
Vol 25 (03) ◽  
pp. 493-511
Author(s):  
Yong Qin ◽  
Shan Yu ◽  
Yuan Zhang ◽  
Limin Jia ◽  
Xiaoqing Cheng
Keyword(s):  
Safety Assessment ◽  
Safety Analysis ◽  
Assessment Method ◽  
Rolling Bearings ◽  
Safety Risk ◽  
Hybrid Intelligence ◽  
Local Mean ◽  
Interval Type ◽  
Service State

Facing the important issues of safety analysis and assessment for the train service state, an online quantified safety assessment method based on the safety region estimation and hybrid intelligence technologies was proposed in this paper. First, the previous researches on the safety analysis and assessment were briefly reviewed for the train itself and its key equipment, and the existential problems were further pointed out. Then, using the safety monitoring data and the safety region estimation theory, a new online safety assessment method with data-driven was put forward, which was followed by a detailed description of the concrete implementation steps including the EMD (Local Mean Decomposition) and EM (Energy Moment) based safety risk evaluation index selection, Interval Type 2 Fuzzy C-Means (IT2FCM) clustering based safety region boundary calculation modeling and safety risk grading. Finally, in order to verify its performance through experiments, the above method was applied in analyzing and evaluating service states of the rolling bearings, the key equipment of the train, on the basis of mass field data. The experimental results indicate that this method is valid.

Mathematical Approaches in Functional Safety Assessment for E/E/PE Safety-Related Software

2021 ◽  
pp. 2150043
Author(s):  
Shinji Inoue ◽  
Takaji Fujiwara ◽  
Shigeru Yamada
Keyword(s):  
Software Reliability ◽  
Safety Assessment ◽  
Assessment Method ◽  
Functional Safety ◽  
Reliability Modeling ◽  
Software Failure ◽  
Safety Integrity Level ◽  
Iec 61508 ◽  
Systematic Failure ◽  
Quantitative Safety Assessment

Safety integrity level (SIL)-based functional safety assessment is widely required in designing safety functions and checking their validity of electrical/electronic/programmable electronic (E/E/PE) safety-related systems after being issued IEC 61508 in 2010. For the hardware of E/E/PE safety-related systems, quantitative functional safety assessment based on target failure measures is needed for deciding or allocating the level of SIL. On the other hand, IEC 61508 does not provide any quantitative safety assessment method for allocating SIL for the software of E/E/PE safety-related systems because the software failure is treated as a systematic failure in IEC 61508. We discuss the needfulness of quantitative safety assessment for software of E/E/PE safety-related systems and propose mathematical fundamentals for conducting quantitative SIL-based safety assessment for the software of E/E/PE safety-related systems by applying the notion of software reliability modeling and assessment technologies. We show numerical examples for explaining how to use our approaches.

A fatal waterborne disease epidemic in Walkerton, Ontario: comparison with other waterborne outbreaks in the developed world

2003 ◽  
Vol 47 (3) ◽  
pp. 7-14 ◽  
Author(s):  
S.E. Hrudey ◽  
P. Payment ◽  
P.M. Huck ◽  
R.W. Gillham ◽  
E.J. Hrudey
Keyword(s):  
Drinking Water ◽  
Water Security ◽  
Reference Source ◽  
Water Safety ◽  
Drinking Water Safety ◽  
Public Inquiry ◽  
Contaminated Drinking Water ◽  
The Government ◽  
Safety Of Drinking Water ◽  
Developed World

An estimated 2,300 people became seriously ill and seven died from exposure to microbially contaminated drinking water in the town of Walkerton, Ontario, Canada in May 2000. The severity of this drinking water disaster resulted in the Government of Ontario calling a public inquiry by Mr. Justice Dennis O’Connor to address the cause of the outbreak, the role (if any) of government policies in contributing to this outbreak and, ultimately, the implications of this experience on the safety of drinking water across the Province of Ontario. The circumstances surrounding the Walkerton tragedy are an important reference source for those concerned with providing safe drinking water. Although some circumstances are obviously specific to this epidemic, others are uncomfortably reminiscent of waterborne outbreaks that have occurred elsewhere. These recurring themes suggested the need for attention to broad issues of drinking water security and they present the challenge for how drinking water safety can be managed to prevent such tragedies in the future.

Sign in / Sign up

Export Citation Format

Share Document