scholarly journals Reliability of Existing Climate Indices in Assessing the Freeze-Thaw Damage Risk of Internally Insulated Masonry Walls

Buildings ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 482
Author(s):  
Sahar Sahyoun ◽  
Hua Ge ◽  
Michael A. Lacasse ◽  
Maurice Defo
Keyword(s):  
Risk Assessment ◽  
Risk Index ◽  
Climate Scenario ◽  
Evaluation Methodology ◽  
Climate Indices ◽  
Moisture Index ◽  
Climatic Index ◽  
Actual Performance ◽  
Freeze Thaw ◽  
Damage Risk

This paper evaluates the reliability of the currently used climate-based indices in selecting a moisture reference year (MRY) for the freeze-thaw (FT) damage risk assessment of internally insulated solid brick walls. The evaluation methodology compares the ranking of the years determined by the climate-based indices and response-based indices from simulations, regarded as actual performance. The hygrothermal response of an old brick masonry wall assembly, before and after retrofit, was investigated in two Canadian cities under historical and projected future climates. Results indicated that climate-based indices failed to represent the actual performance. However, among the response-based indices, the freeze-thaw damage risk index (FTDR) showed a better correlation with the climate-based indices. Additionally, results indicated a better correlation between the climatic index (CI), the moisture index (MI), and FTDR in Ottawa; however, in Vancouver, a better fit was found between MI and FTDR. Moreover, the risk of freeze-thaw increased considerably after interior insulation was added under both historical and projected future climates. The risk of FT damage would increase for Ottawa but decrease for Vancouver under a warming climate projected in the future, based on the climate scenario used in this study. Further research is needed to develop a more reliable method for the ranking and the selection of MRYs on the basis of climate-based indices that is suitable for freeze-thaw damage risk assessment.

Damage Prediction Using Heavy Rain Risk Assessment: (1) Estimation of Heavy Rain Damage Risk Index

2017 ◽  
Vol 17 (2) ◽  
pp. 361-370 ◽  
Author(s):  
Jongsung Kim ◽  
◽  
Changhyun Choi ◽  
Jongso Lee ◽  
Hung Soo Kim ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Risk Index ◽  
Heavy Rain ◽  
Damage Prediction ◽  
Damage Risk

scholarly journals Environmental Risk Assessment of Petroleum Activities in Surface Sediments, Suez Gulf, Egypt

2021 ◽  
Vol 9 (5) ◽  
pp. 473
Author(s):  
Magda M. Abou El-Safa ◽  
Mohamed Gad ◽  
Ebrahem M. Eid ◽  
Ashwaq M. Alnemari ◽  
Mohammed H. Almarshadi ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Risk Assessment ◽  
Heavy Metal ◽  
Surface Sediment ◽  
Surface Sediments ◽  
Surf Zone ◽  
Risk Index ◽  
Negative Relationship ◽  
Anthropogenic Sources ◽  
Suez Gulf

The present study focuses on the risk assessment of heavy metal contamination in aquatic ecosystems by evaluating the current situation of heavy metals in seven locations (North Amer El Bahry, Amer, Bakr, Ras Gharib, July Water Floud, Ras Shokeir, and El Marageen) along the Suez Gulf coast that are well-known representative sites for petroleum activities in Egypt. One hundred and forty-six samples of surface sediments were carefully collected from twenty-seven profiles in the intertidal and surf zone. The hydrochemical parameters, such as pH and salinity (S‰), were measured during sample collection. The mineralogy study was carried out by an X-ray diffractometer (XRD), and the concentrations of Al, Mn, Fe, Cr, Cu, Co, Zn, Cd, and Pb were determined using inductively coupled plasma mass spectra (ICP-MS). The ecological risks of heavy metals were assessed by applying the contamination factor (CF), enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI), and potential ecological risk index (RI). The mineralogical composition mainly comprised quartz, dolomites, calcite, and feldspars. The average concentrations of the detected heavy metals, in descending order, were Al > Fe > Mn > Cr > Pb > Cu > Zn > Ni > Co > Cd. A non-significant or negative relationship between the heavy metal concentration in the samples and their textural grain size characteristics was observed. The coastal surface sediment samples of the Suez Gulf contained lower concentrations of heavy metals than those published for other regions in the world with petroleum activities, except for Al, Mn, and Cr. The results for the CF, EF, and Igeo showed that Cd and Pb have severe enrichment in surface sediment and are derived from anthropogenic sources, while Al, Mn, Fe, Cr, Co, Ni, Cu, and Zn originate from natural sources. By comparison, the PLI and RI results indicate that the North Amer El Bahry and July Water Floud are considered polluted areas due to their petroleum activities. The continuous monitoring and assessment of pollutants in the Suez Gulf will aid in the protection of the environment and the sustainability of resources.

scholarly journals Reforestation Impacted Soil Heavy Metal Fractionation and Related Risk Assessment in the Karst Area, Southwest China

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 891
Author(s):  
Qian Zhang ◽  
Guilin Han ◽  
Xingliang Xu
Keyword(s):  
Heavy Metals ◽  
Risk Assessment ◽  
Ecological Risk ◽  
Southwest China ◽  
Risk Index ◽  
Contamination Factor ◽  
Karst Area ◽  
Risk Assessment Code ◽  
Bcr Sequential Extraction ◽  
Soil Heavy Metals

Human agricultural activities have resulted in widespread land degradation and soil contamination in the karst areas. However, the effects of reforestation after agricultural abandonment on the mobility risks and contamination of heavy metals have been rarely reported. In the present study, six soil profiles were selected from cropland and abandoned cropland with reforestation in the Puding karst regions of Southwest China. The Community Bureau of Reference (BCR) sequential extraction method was used to evaluate the compositions of different chemical fractions of soil heavy metals, including Fe, Mn, Cr, Zn, Ni, and Cd. The total contents of Cr, Ni, Zn, Cd, and Mn in the croplands were significantly higher than those in the abandoned croplands. For all soils, Cr, Ni, Zn, and Fe were mainly concentrated in the residual fractions (>85%), whereas Mn and Cd were mostly observed in the non-residual fractions (>65%). The non-residual fractions of Cd, Cr, Ni, and Zn in the croplands were higher than those in the abandoned croplands. These results indicated that the content and mobility of soil heavy metals decreased after reforestation. The individual contamination factor (ICF) and risk assessment code (RAC) showed that Cd contributed to considerable contamination of karst soils. The global contamination factor (GCF) and potential ecological risk index (RI) suggested low contamination and ecological risk of the investigated heavy metals in the croplands, moreover they can be further reduced after reforestation.

scholarly journals The potential use of lightweight cellular concrete in pavement application: a review

2020 ◽  
Vol 13 (6) ◽  
pp. 686-696
Author(s):  
Frank Mi-Way Ni ◽  
Abimbola Grace Oyeyi ◽  
Susan Tighe
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ease Of Use ◽  
Potential Candidate ◽  
Actual Performance ◽  
Freeze Thaw ◽  
Lower Weight ◽  
And Performance ◽  
Potential Use ◽  
Cellular Concrete

AbstractProtecting the pavement subgrade to increase the service life of road pavements is an aspect currently being explored. Several alternative pavement subbase materials are being considered, including Lightweight Cellular Concrete (LCC). Due to its lower weight, LCC incorporating industrial by-product, making it sustainable, and ease of use amongst other benefits, is seen as a potential candidate. This paper reports reviewing the potential application of LCC within the pavement structure with a specific application as a subbase. It examines the various properties such as modulus of elasticity, compressive and tensile strength, Water absorption, and freeze-thaw resistance necessary for pavement application. It also assesses its use in the field in Canada considering the design methods utilized. Some limitations and gaps for LCC application in pavements are also established and recommendations on how to further its use and performance. This review concludes that LCC possesses potential as a pavement subbase alternative; however, other mechanical properties like LCC’s fatigue life is essential. A comparative field study is also recommended to monitor actual performance and various factors on performance.

scholarly journals Speciation Variation and Comprehensive Risk Assessment of Metal(loid)s in Surface Sediments of Intertidal Zones

2018 ◽  
Vol 15 (10) ◽  
pp. 2125 ◽  
Author(s):  
Baocui Liang ◽  
Xiao Qian ◽  
Shitao Peng ◽  
Xinhui Liu ◽  
Lili Bai ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Surface Sediments ◽  
Yellow River ◽  
Biological Effects ◽  
Risk Index ◽  
Sediment Quality ◽  
Residual Fraction ◽  
Intertidal Zones ◽  
Probable Effect Level ◽  
Effect Level

Speciation variation and comprehensive risk assessment of metal(loid)s (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were investigated in surface sediments from the intertidal zones of the Yellow River Delta, China. Results showed that only the concentrations of As, Cd and Pb were significantly different between April and September (p < 0.01). In April, the residual fraction (F4) was predominant for As, Cr, Cu, Ni and Zn. However, the exchangeable and carbonate-associated fraction (F1) was dominant for Cd averaging 49.14% indicating a high environmental risk. In September, the F4 fraction was predominant and the F1 fraction was very low for most metal(loid)s except Cd and Mn. The geo-accumulation index (Igeo), the F1 fraction and potential ecological risk index (PERI) of most metal(loid)s were relatively low in surface sediments for both seasons. But Pb, As and Ni were between the threshold effect level (TEL)and the probable effect level (PEL) for 66.67%, 83.33% and 91.67% in April and As and Ni were between TEL and PEL for 41.67% and 91.67%, which indicated that the concentration of them was likely to occasionally exhibit adverse effects on the ecosystem. Although the Igeo, the F1 fraction or PERI of Cd in both seasons was higher at some sites, the results of sediment quality guidelines (SQGs) indicated that the biological effects of Cd were rarely observed in the studied area.

scholarly journals Safety Risk Assessment of Tourism Management System Based on PSO-BP Neural Network

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Wenru Guo
Keyword(s):  
Neural Network ◽  
Risk Assessment ◽  
Management System ◽  
Evaluation Model ◽  
Risk Index ◽  
Security Risk ◽  
Bp Network ◽  
Model Based ◽  
Tourism Management ◽  
Better Than

With the development of science and technology, system management is gradually applied to tourism management. How to correctly assess the security risks of the tourism management system has become an important means to maintain passenger information. The security risk index of the travel management system is input into the PSO-BP network as a sample, and the corresponding risk value of the index is used as the network output. The results show that the error results, accuracy (96.53%), training time (216 s), number of iterations (275 times), and convergence speed are all better than traditional BP network. The relative error of PSO-BP network (0.32%) is better than that of BP network, with 300 iterations, and the error is close to 10–5. The average evaluation accuracy of S based on PSO-BP network is 99.72%, and the average time consumed is 2.512 s. It is superior to the evaluation model based on fuzzy set and entropy weight theory and the evaluation model based on gray correlation analysis and radial basis function neural network. In conclusion, the security risk assessment of the tourism management system based on PSO-BP network can effectively assess the security risk of the tourism management system.

RISK ASSESSMENT OF SUCCESSFUL IMPLEMENTATION OF SPOOFING ATTACKS ON VOICE AUTHENTICATION ELEMENTS IN DISTRIBUTED COMPUTER SYSTEMS

2021 ◽  
pp. 115-126
Author(s):  
Александр Александрович Хайдаров ◽  
Сергей Александрович Бодячевский ◽  
Николай Николаевич Толстых
Keyword(s):  
Risk Assessment ◽  
Evaluation Process ◽  
Evaluation Methodology ◽  
Successful Implementation ◽  
Load Testing ◽  
Biometric Systems ◽  
The Moment ◽  
Technical Solutions ◽  
The Impact ◽  
Distributed Computer Systems

Цель исследования заключается в рекомендациях по улучшению мер защиты голосовых систем аутентификации от реализации спуфинг-атак. В работе рассмотрены разнообразные виды спуфинг-атак и выделены самые опасные на данный момент. Разработана методика оценки защищенности голосовых систем аутентификации, учитывающая воздействие различных видов спуфиг-атак на системы голосовой аутентификации. Проведены количественные эксперименты, показывающие преимущество разработанной методики, в сравнении с существующими аналогами. Описан комплекс программных средств оценки защищенности систем голосовой аутентификации, который позволяет автоматизировать процесс оценки при проведении технологических испытаний. Полученные результаты могут быть использованы не только для оценки защищенности систем голосовой аутентификации, но и для проведения функционального и нагрузочного тестирования. Применение предложенного комплекса и методики оценки в дальнейшем может помочь в разработке технических решений по увеличению защищенности голосовых биометрических систем от реализации спуфинг-атак. The purpose of the study is to provide recommendations for improving the protection of voice authentication systems against spoofing attacks. The paper considers various types of spoofing attacks and identifies the most dangerous ones at the moment. A method for assessing the security of voice authentication systems has been developed, taking into account the impact of various types of spoofing attacks on voice authentication systems. Quantitative experiments were carried out, showing the advantage of the developed method in comparison with existing analogues. A set of software tools for assessing the security of voice authentication systems is described, which allows you to automate the evaluation process during technological tests. The results obtained can be used not only to assess the security of voice authentication systems, but also to conduct functional and load testing. The use of the proposed complex and evaluation methodology in the future can help in the development of technical solutions to increase the security of voice biometric systems from spoofing attacks.

A quantitative risk assessment methodology and evaluation of food supply chain

2017 ◽  
Vol 28 (4) ◽  
pp. 1272-1293 ◽  
Author(s):  
Rishabh Rathore ◽  
Jitesh J. Thakkar ◽  
Jitendra Kumar Jha
Keyword(s):  
Risk Assessment ◽  
Supply Chain ◽  
Food Supply ◽  
Social Issues ◽  
Risk Index ◽  
Mitigation Strategies ◽  
Quantitative Risk Assessment ◽  
Food Supply Chain ◽  
Content Type ◽  
Risk Quantification

Purpose The food supply chain is exposed to severe environmental and social issues with serious economic consequences. The identification and assessment of risk involved in the food supply chain can help to overcome these challenges. In response, the purpose of this paper is to develop a risk assessment framework for a typical food supply chain. Design/methodology/approach An integrated methodology of grey analytical hierarchy process and grey technique for order preference by similarity to the ideal solution is proposed for developing a comprehensive risk index. The opinion of the experts is used to illustrate an application of the proposed methodology for the risk assessment of the food supply chain in India. Findings Valuable insights and recommendations are drawn from the results, which are helpful to the practitioners working at strategic and tactical levels in the food supply chain for minimising the supply chain disruptions. Research limitations/implications The risk quantification for the case organisation is primarily based on inputs collected from the experts working for Indian food supply chain, and so the generalisation of the results is limited to the context of developing countries. However, the generalisability of the proposed risk quantification methodology and key insights developed in the food supply chain will assist practitioners in policy making. Practical implications The risk priorities established by this research would enable an implementation of systematic risk mitigation strategies and deployment of necessary resources for leveraging the efficiency of food supply chain. Originality/value Specifically, this research has delivered a risk quantification framework and strengthened the inquiry of risk management for the food supply chain.

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