POSSIBILISTIC SAFETY ASSESSMENT OF HYBRID UNCERTAIN SYSTEMS

2013 ◽  
Vol 20 (01) ◽  
pp. 1350002 ◽  
Author(s):  
PALASH CHANDRA SAM ◽  
SUBRATA CHAKRABORTY
Keyword(s):  
Safety Assessment ◽  
Uncertain Systems ◽  
Evidence Theory ◽  
Safety Evaluation ◽  
Uncertain System ◽  
Probability Of Failure ◽  
Structural Parameter ◽  
Structural Systems ◽  
Input Parameters

The safety evaluations of structures are usually performed by assuming uncertain 18 input parameters either as probabilistic or possibilistic in nature. Safety evaluations of structural systems characterized by some of the input parameters as possibilistic and others that are sufficient enough to model as probabilistic are unsuitable and restricted to gross assumption at early stages of modeling. The present paper deals with the safety analysis of such a hybrid uncertain system. Relying on the fundamental concept of entropy-based transformation; the feasibility of reliability analysis of a hybrid uncertain system in a possibilistic format is demonstrated in the present study. This will enable the designers to model the structural parameter uncertainty probabilistically as well possibilistically depending on the nature and quality of the input data. The bounds on the probability of failure based on the evidence theory are also computed to study the consistency of the possibility of failure results obtained by the transformation-based algorithm. A numerical example illustrates the capability of the proposed possibilistic approach of safety evaluation of hybrid uncertain system.

Analysis of the Safety Factors of Municipal Road Undercrossing Existing Bridge Based on Fuzzy Analytic Hierarchy Process Methods

2021 ◽  
pp. 036119812110318
Author(s):  
Yonghong Yang ◽  
Yu Chen ◽  
Zude Tang
Keyword(s):  
Safety Assessment ◽  
Evaluation Method ◽  
Comprehensive Evaluation ◽  
Safety Evaluation ◽  
Safety Factors ◽  
Analytic Hierarchy ◽  
Road Engineering ◽  
Existing Bridges ◽  
Hierarchy Process ◽  
Engineering Projects

Increasing traffic volume and insufficient road lanes often require municipal roads to be reconstructed and expanded. Where a road passes under a bridge, the reconstruction and expansion project will inevitably have an impact on the bridge. To evaluate the safety impact of road engineering projects on bridges, this paper evaluates the safety of the roads and ancillary facilities of highway bridges involved in municipal road engineering projects. Based on a comprehensive analysis of the safety factors of municipal roads undercrossing existing bridges, a fuzzy comprehensive analytic hierarchy process (AHP) evaluation method for the influence of road construction on the safety of existing bridges is proposed. First, AHP is used to select 11 evaluation factors. Second, the target layer, criterion layer, and index layer of evaluation factors are established, then a safety evaluation factor system is formed. The three-scale AHP model is used to determine the weight of assessment indexes. Third, through the fuzzy comprehensive AHP evaluation model, the fuzzy hierarchical comprehensive evaluation is carried out for the safety assessment index system. Finally, the fuzzy comprehensive evaluation method is applied to the engineering example of a municipal road undercrossing an existing expressway bridge. The comprehensive safety evaluation of the existing bridge reflects the practicability and feasibility of the method. It is expected that, with further development, the method will improve the decision-making process in bridge safety assessment systems.

scholarly journals Development and Validation of a Post-Earthquake Safety Assessment System for High-Rise Buildings Using Acceleration Measurements

Mathematics ◽  
2021 ◽  
Vol 9 (15) ◽  
pp. 1758
Author(s):  
Koji Tsuchimoto ◽  
Yasutaka Narazaki ◽  
Billie F. Spencer
Keyword(s):  
Safety Assessment ◽  
Large Scale ◽  
Model Updating ◽  
Safety Evaluation ◽  
Assessment System ◽  
Shaking Table ◽  
Structural Safety ◽  
High Rise ◽  
Steel Building ◽  
Earthquake Safety

After a major seismic event, structural safety inspections by qualified experts are required prior to reoccupying a building and resuming operation. Such manual inspections are generally performed by teams of two or more experts and are time consuming, labor intensive, subjective in nature, and potentially put the lives of the inspectors in danger. The authors reported previously on the system for a rapid post-earthquake safety assessment of buildings using sparse acceleration data. The proposed framework was demonstrated using simulation of a five-story steel building modeled with three-dimensional nonlinear analysis subjected to historical earthquakes. The results confirmed the potential of the proposed approach for rapid safety evaluation of buildings after seismic events. However, experimental validation on large-scale structures is required prior to field implementation. Moreover, an extension to the assessment of high-rise buildings, such as those commonly used for residences and offices in modern cities, is needed. To this end, a 1/3-scale 18-story experimental steel building tested on the shaking table at E-Defense in Japan is considered. The importance of online model updating of the linear building model used to calculate the Damage Sensitive Features (DSFs) during the operation is also discussed. Experimental results confirm the efficacy of the proposed approach for rapid post-earthquake safety evaluation for high-rise buildings. Finally, a cost-benefit analysis with respect to the number of sensors used is presented.

scholarly journals The Effectiveness of Acupuncture in Management of Functional Constipation: A Systematic Review and Meta-Analysis

2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Lu Wang ◽  
Mingmin Xu ◽  
Qianhua Zheng ◽  
Wei Zhang ◽  
Ying Li
Keyword(s):  
Quality Of Life ◽  
Meta Analysis ◽  
Safety Evaluation ◽  
Functional Constipation ◽  
Responder Rate ◽  
Current Evidence ◽  
Cochrane Library ◽  
China National Knowledge Infrastructure ◽  
Increased Risk

Objective. The purpose of this study was to assess the effectiveness and safety of acupuncture for functional constipation (FC). Methods. A rigorous literature search was performed in English (PubMed, Web of Science, the Cochrane Library, and EMBASE) and Chinese (China National Knowledge Infrastructure (CNKI), Chinese Biological Medical (CBM), Wanfang database, and China Science and Technology Journal (VIP)) electronic databases from their inception to October 2019. Included randomized controlled trials (RCTs) compared acupuncture therapy with sham acupuncture or pharmacological therapies. The outcome measures were evaluated, including the primary outcome of complete spontaneous bowel movement (CSBM) and secondary outcomes of Bristol Stool Form Scale (BSFS), constipation symptoms scores (CSS), responder rate, the Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire, and safety evaluation. Meta-analysis was performed by using RevMan5.3. Results. The merged data of 28 RCTs with 3525 participants indicated that acupuncture may be efficient for FC by increasing CSBMs (p<0.00001; MD = 0.84 [95% CI, 0.65 to 1.03]; I2 = 0%) and improving constipation symptoms (p=0.03; SMD = −0.4 [95% CI, −0.78 to −0.03]; I2 = 74%), stool formation (p<0.00001; MD = 0.24 [95% CI, 0.15 to 0.34]; I2 = 0%), quality of life (p<0.00001; N = 1, MD = −0.33 [95% CI, −0.45 to −0.21]), and responder rates (p=0.02; RR = 2.16; [95% CI, 1.1 to 4.24]; I2 = 69%) compared with the effects of sham treatment. No increased risk of adverse events was observed (p=0.44; RR = 1.18; [95% CI, 0.77 to 1.81]; I2 = 0%). With regard to medication comparisons, the pooled data indicated that acupuncture was more effective in increasing CSBMs (p=0.004; MD = 0.53 [95% CI, 0.17 to 0.88]; I2 = 88%) and improving patients’ quality of life (p<0.00001; SMD = −0.73 [95% CI, −1.02 to −0.44]; I2 = 64%), with high heterogeneity. However, there were no significant differences in responder rate (p=0.12; RR = 1.31; [95% CI, 0.94 to 1.82]; I2 = 53%), BSFS (p=0.5; MD = 0.17 [95% CI, −0.33 to 0.68]; I2 = 93%), or CSS (p=0.05; SMD = −0.62 [95% CI, −1.23 to −0.01]; I2 = 89%). Regarding safety evaluation, acupuncture was safer than medications (p<0.0001; RR = 0.3; [95% CI, 0.18 to 0.52]; I2 = 30%). Conclusions. Current evidence suggests that acupuncture is an efficient and safe treatment for FC. Acupuncture increased stool frequency, improved stool formation, alleviated constipation symptoms, and improved quality of life. However, the evidence quality was relatively low and the relationship between acupuncture and drugs is not clear. More high-quality trials are recommended in the future. PROSPERO registration number: CRD42019143347.

Structural Safety Assessment of a 1100 TEU Container Ship, Based on a Enhanced Long Term Fatigue Analysis

2014 ◽  
Vol 1036 ◽  
pp. 935-940
Author(s):  
Leonard Domnisoru ◽  
Ionica Rubanenco ◽  
Mihaela Amoraritei
Keyword(s):  
Safety Assessment ◽  
Safety Evaluation ◽  
Irregular Waves ◽  
Structural Safety ◽  
Random Wave ◽  
Wave Loads ◽  
Strength Assessment ◽  
Integrated Method ◽  
Hydroelastic Response

This paper is focused on an enhanced integrated method for structural safety assessment of maritime ships under extreme random wave loads. In this study is considered an 1100 TEU container test ship, with speed range 0 to 18 knots. The most comprehensive criteria for ships structural safety evaluation over the whole exploitation life is based on the long term ship structures analysis, that includes: stress hot-spots evaluation by 3D/1D-FEM hull models, computation of short term ship dynamic response induced by irregular waves, long term fatigue structure assessment. The analysis is enhanced by taking into account the ships speed influence on hydroelastic response. The study includes a comparative analysis on two scenarios for the correlation between the ships speed and waves intensity. The standard constant ship speed scenario and CENTEC scenario, with total speed loss at extreme waves condition, are considered. Instead of 20 years ship exploitation life estimated by classification societies rules from the long term structural safety criteria, the enhanced method has predicted more restrictive values of 14.4-15.7 years. The numerical analyses are based on own software and user subroutines. The study made possible to have a more realistic approach of ships structural strength assessment, for elastic and faster ships as container carriers, in compare to the standard one based only on naval rules, delivering a method with higher confidence in the designed structural safety.

scholarly journals Safety assessment of essential medicines for elderly people: a bibliographic survey

2014 ◽  
Vol 50 (2) ◽  
pp. 269-284 ◽  
Author(s):  
Fabiana Rossi Varallo ◽  
Fernanda Mariana de Oliveira ◽  
Patrícia de Carvalho Mastroianni
Keyword(s):  
Elderly People ◽  
Safety Assessment ◽  
Search Strategy ◽  
Adverse Drug Events ◽  
The Elderly ◽  
Essential Medicines ◽  
Age Group ◽  
Over The Counter ◽  
Manual Search

Certain medicines are considered potentially inappropriate (PIM) for elderly people as they increase the risk of adverse drug events (ADE) and because safer alternative therapies are available on the market. In this context, in order to identify the instruments that assess the quality of medical prescriptions for elderly and to determine which drugs are considered PIM, a bibliographic survey was conducted in PUBMED, LILACS and PAHO databases, in February and March/2010. The search strategy included the use of health descriptors and a manual search in the references cited by selected papers. During the period of data collection, 15 instruments were identified. In 2012, with the publication of the update of Beers criteria, this instrument was included in the study. We identified 163 PIM of 25 therapeutic classes, of which 125 (76.7%) are marketed in Brazil. Of these, 31 (24.8%) are essential medicines (RENAME 2012), of which 13 have safer therapeutic equivalents and 19 (15.2%) are over-the-counter drugs. Data suggest the need for inclusion of safer alternatives for the elderly in the national list of essential medicines and the pharmaceutical care for early detection of ADE in this age group, in order to contribute to the safe use of medicines.

scholarly journals Problems with the outcome measures in randomized controlled trials of traditional Chinese medicine in treating chronic heart failure caused by coronary heart disease: a systematic review

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jiayuan Hu ◽  
Ruijin Qiu ◽  
Chengyu Li ◽  
Min Li ◽  
Qianqian Dai ◽  
...  
Keyword(s):  
Heart Failure ◽  
Outcome Measures ◽  
Safety Evaluation ◽  
Reporting Quality ◽  
Risk Of Bias ◽  
Efficacy And Safety ◽  
End Points ◽  
Randomized Controlled ◽  
Surrogate Outcomes

Abstract Background Traditional Chinese medicine (TCM) has gained widespread application in treating chronic heart failure (CHF) secondary to coronary heart disease (CHD). However, the sound clinical evidence is still lacking. Corresponding clinical trials vary considerably in the outcome measures assessing the efficacy of TCM, some that showed the improvement of clinical symptoms are not universally acknowledged. Rational outcome measures are the key to evaluate efficacy and safety of each treatment and significant elements of a convincing clinical trial. We aimed to summarize and analyze outcome measures in randomized controlled trials (RCTs) of TCM in treating CHF caused by CHD, subsequently identify the present problems and try to put forward solutions. Methods We systematically searched databases including Embase, PubMed, Cochrane Library, CBM, CNKI, VIP and Wanfang from inception to October 8, 2018, to identify eligible RCTs using TCM interventions for treating CHF patients caused by CHD. Cochrane Database of Systematic Reviews (CDSR) was searched to include Cochrane systematic reviews (CSRs) of CHF. Two authors independently assessed the risk of bias of the included RCTs according to the Cochrane Handbook. Outcome measures of each trial were extracted and analyzed those compared with the CSRs. We also evaluated the reporting quality of the outcome measures. Results A total of 31 RCTs were included and the methodology quality of the studies was generally low. Outcome measures in these RCTs were mortality, rehospitalization, efficacy of cardiac function, left ventricular ejection fraction (LVEF), 6 min’ walk distance (6MWD) and Brain natriuretic peptide (BNP), of which mortality and rehospitalization are clinical end points while the others are surrogate outcomes. The reporting rate of mortality and rehospitalization was 12.90% (4/31), the other included studies reported surrogate outcomes. As safety measure, 54.84% of the studies reported adverse drug reactions. Two trials were evaluated as high in reporting quality of outcomes and that of the other 29 studies was poor due to lack of necessary information for reporting. Conclusions The present RCTs of TCM in treating CHF secondary to CHD did not concentrate on the clinical end points of heart failure, which were generally small in size and short in duration. Moreover, these trials lacked adequate safety evaluation, had low quality in reporting outcomes and certain risk of bias in methodology. For objective assessment of the efficacy and safety of TCM in treating CHF secondary to CHD, future research should be rigorous designed, set end points as primary outcome measures and pay more attention to safety evaluation throughout the trial.

scholarly journals Multi-source data fusion method for structural safety assessment of water diversion structures

2021 ◽  
Author(s):  
Sherong Zhang ◽  
Ting Liu ◽  
Chao Wang
Keyword(s):  
Data Fusion ◽  
Safety Assessment ◽  
Evidence Theory ◽  
Weighted Average ◽  
Water Diversion ◽  
Sensor Data ◽  
Structural Safety ◽  
Fusion Method ◽  
Bhattacharyya Distance ◽  
Source Data

Abstract Building safety assessment based on single sensor data has the problems of low reliability and high uncertainty. Therefore, this paper proposes a novel multi-source sensor data fusion method based on Improved Dempster–Shafer (D-S) evidence theory and Back Propagation Neural Network (BPNN). Before data fusion, the improved self-support function is adopted to preprocess the original data. The process of data fusion is divided into three steps: Firstly, the feature of the same kind of sensor data is extracted by the adaptive weighted average method as the input source of BPNN. Then, BPNN is trained and its output is used as the basic probability assignment (BPA) of D-S evidence theory. Finally, Bhattacharyya Distance (BD) is introduced to improve D-S evidence theory from two aspects of evidence distance and conflict factors, and multi-source data fusion is realized by D-S synthesis rules. In practical application, a three-level information fusion framework of the data level, the feature level, and the decision level is proposed, and the safety status of buildings is evaluated by using multi-source sensor data. The results show that compared with the fusion result of the traditional D-S evidence theory, the algorithm improves the accuracy of the overall safety state assessment of the building and reduces the MSE from 0.18 to 0.01%.

scholarly journals Cost-effectiveness of implementing objective diagnostic verification of asthma in the United States

2019 ◽  
Author(s):  
Mohsen Yaghoubi ◽  
Amin Adibi ◽  
Zafar Zafari ◽  
J Mark FitzGerald ◽  
Shawn D. Aaron ◽  
...  
Keyword(s):  
Quality Of Life ◽  
United States ◽  
Cost Effectiveness ◽  
The United States ◽  
Model Parameters ◽  
List Type ◽  
Asthma Diagnosis ◽  
Verification Algorithm ◽  
Input Parameters

AbstractBackgroundAsthma diagnosis in the community is often made without objective testing.ObjectiveThe aim of this study was to evaluate the cost-effectiveness of implementing a stepwise objective diagnostic verification algorithm among patients with community-diagnosed asthma in the United States (US).MethodsWe developed a probabilistic time-in-state cohort model that compared a stepwise asthma verification algorithm based on spirometry and methacholine challenge test against the current standard of care over 20 years. Model input parameters were informed from the literature and with original data analyses when required. The target population was US adults (≥15 y/o) with physician-diagnosed asthma. The final outcomes were costs (in 2018 $) and quality-adjusted life years (QALYs), discounted at 3% annually. Deterministic and probabilistic analyses were undertaken to examine the effect of alternative assumptions and uncertainty in model parameters on the results.ResultsIn a simulated cohort of 10,000 adults with diagnosed asthma, the stepwise algorithm resulted in the removal of diagnosis in 3,366. This was projected to be associated with savings of $36.26 million in direct costs and a gain of 4,049.28 QALYs over 20 years. Extrapolating these results to the US population indicated an undiscounted potential savings of $56.48 billion over 20 years. Results were robust against alternative assumptions and plausible changes in values of input parameters.ConclusionImplementation of a simple diagnostic testing algorithm to verify asthma diagnosis might result in substantial savings and improvement in patients’ quality of life.Key MessagesCompared with current standards of practice, the implementation of an asthma verification algorithm among US adults with diagnosed asthma can be associated with reduction in costs and gain in quality of life.There is substantial room for improving patient care and outcomes through promoting objective asthma diagnosis.Capsule summaryAsthma ‘overdiagnosis’ is common among US adults. An objective, stepwise verification algorithm for re-evaluation of asthma diagnosis can result in substantial savings in costs and improvements in quality of life.

Authentic Emergence of Flexibility in Contemporary Architecture

2015 ◽  
Vol 40 (4) ◽  
pp. 44-49
Author(s):  
Ghazal Farjami
Keyword(s):  
Spatial Configuration ◽  
Environmental Issues ◽  
Modern Architecture ◽  
Structural Systems ◽  
Traditional Architecture ◽  
Modern Period ◽  
Contemporary Architecture ◽  
Modern Era ◽  
Residential Projects

Flexibility is known as an important term in the field of open buildings especially during modern era. Idea of flexibility has been one of the prominent implications in traditional Iranian architecture emerged in spatial organizations. Although, during modern period this quality of spaces has been mostly ignored some of the contemporary architects attempted to reconsider this characteristic in their projects. However, providing an interview with 7 pioneering contemporary Iranian architects and visiting their 25 residential projects it seems that flexibility has been reinterpreted in some of their projects. This research is an attempt for examining the idea of flexibility in 6 projects of 3 of these architects who were obsessed with this spatial term in their architectural works. Based on the architect’s words and analysis of their projects, and also looking for the roots of flexibility in traditional architecture, it can be asserted that there is an authentic emergence of flexibility in these projects. Examining these projects according to three main indicators of flexibility in modern architecture as structural systems, service organization and architectural layout, it is also tried to find their relation with traditional architecture. Being adapted with new lifestyles while ingrained in cultural and environmental issues of its context, idea of flexibility employed as an authentic characteristic of spatial configuration in some of the contemporary buildings in Iran.

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