Search results for: warehouse failure risk

Authors: Saeedeh Bakhtiari, Johannes Depessemier, Stijn Hertelé, Wim De Waele

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High cycle fatigue comprising up to 10⁷ load cycles has been the subject of many studies, and the behavior of many materials was recorded adequately in this regime. However, many applications involve larger numbers of load cycles during the lifetime of machine components. In this ultra-high cycle regime, other failure mechanisms play, and the concept of a fatigue endurance limit (assumed for materials such as steel) is often an oversimplification of reality. When machine component design demands a high geometrical complexity, cast iron grades become interesting candidate materials. Grey cast iron is known for its low cost, high compressive strength, and good damping properties. However, the ultra-high cycle fatigue behavior of cast iron is poorly documented. The current work focuses on the ultra-high cycle fatigue behavior of EN-GJL-250 (GG25) grey cast iron by developing an ultrasonic (20 kHz) fatigue testing system. Moreover, the testing machine is instrumented to measure the temperature and the displacement of  the specimen, and to control the temperature. The high resonance frequency allowed to assess the  behavior of the cast iron of interest within a matter of days for ultra-high numbers of cycles, and repeat the tests to quantify the natural scatter in fatigue resistance.

Keywords: GG25, cast iron, ultra-high cycle fatigue, ultrasonic test

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Authors: Rino Gubiani, Gianfranco Pergher

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The work focused on the statistical analysis of accidents in the forestry sector (2000-2020) in Friuli-Venezia Giulia region, located in the North-East of Italy. The aim of the work was to analyse the evolution of the casualties throughout time and to evaluate possible improvements in the sector. It was shown that even nowadays the rate of accidents in forestry work is higher compared with all the other sectors, including agriculture; moreover, it was highlighted that some accidents remained present throughout the whole analysed range, such as slipping on the soil, being hit by trees and falling down from the plants. The results showed that an increase in forestry exploitation could even increase the total number of accidents, if advanced technological machines, such as cable cranes, would not implemented, given the fact that there is also a significant number of old people (above 50 years old) working in the sector.

Keywords: safety, forestry work, accidents, risk analysis, casualties, statistical analysis

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Authors: F. Al-Mufadi, F. Djavanroodi

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During the last decade ultrafine grained (UFG) and nano-structured (NS) materials have experienced a rapid development. In this research work finite element analysis has been carried out to investigate the plastic strain distribution in equal channel angular process (ECAP). The magnitudes of standard deviation (S. D.) and inhomogeneity index (Ci) were compared for different ECAP passes. Verification of a three-dimensional finite element model was performed with experimental tests. Finally the mechanical property including impact energy of ultrafine grained pure commercially pure Aluminum produced by severe plastic deformation method has been examined. For this aim, equal channel angular pressing die with the channel angle, outer corner angle and channel diameter of 90°, 20° and 20 mm had been designed and manufactured. Commercial pure Aluminum billets were ECAPed up to four passes by route BC at the ambient temperature. The results indicated that there is a great improvement at the hardness measurement, yield strength and ultimate tensile strength after ECAP process. It is found that the magnitudes of HV reach 67 HV from 21 HV after the final stage of process. Also, about 330% and 285% enhancement at the YS and UTS values have been obtained after the fourth pass as compared to the as-received conditions, respectively. On the other hand, the elongation to failure and impact energy have been reduced by 23% and 50% after imposing four passes of ECAP process, respectively.

Keywords: SPD, ECAP, FEM, pure Al, mechanical properties

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Authors: J. Fox, J. Randhawa, M. Chan, L. Campbell, A. Weakely, D. J. Harvey, S. Tomaszewski Farias

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Early identification of individuals at risk for conversion to dementia provides an opportunity for preventative treatment. Many older adults (30-60%) report specific subjective cognitive decline (SCD); however, previous research is inconsistent in terms of what types of complaints predict future cognitive decline. The purpose of this study is to identify which specific complaints from the Everyday Cognition Scales (ECog) scales, a measure of self-reported concerns for everyday abilities across six cognitive domains, are associated with: 1) conversion from a clinical diagnosis of normal to either MCI or dementia (categorical variable) and 2) progressive cognitive decline in memory and executive function (continuous variables). 415 cognitively normal older adults were monitored annually for an average of 5 years. Cox proportional hazards models were used to assess associations between self-reported ECog items and progression to impairment (MCI or dementia). A total of 114 individuals progressed to impairment; the mean time to progression was 4.9 years (SD=3.4 years, range=0.8-13.8). Follow-up models were run controlling for depression. A subset of individuals (n=352) underwent repeat cognitive assessments for an average of 5.3 years. For those individuals, mixed effects models with random intercepts and slopes were used to assess associations between ECog items and change in neuropsychological measures of episodic memory or executive function. Prior to controlling for depression, subjective concerns on five of the eight Everyday Memory items, three of the nine Everyday Language items, one of the seven Everyday Visuospatial items, two of the five Everyday Planning items, and one of the six Everyday Organization items were associated with subsequent diagnostic conversion (HR=1.25 to 1.59, p=0.003 to 0.03). However, after controlling for depression, only two specific complaints of remembering appointments, meetings, and engagements and understanding spoken directions and instructions were associated with subsequent diagnostic conversion. Episodic memory in individuals reporting no concern on ECog items did not significantly change over time (p>0.4). More complaints on seven of the eight Everyday Memory items, three of the nine Everyday Language items, and three of the seven Everyday Visuospatial items were associated with a decline in episodic memory (Interaction estimate=-0.055 to 0.001, p=0.003 to 0.04). Executive function in those reporting no concern on ECog items declined slightly (p <0.001 to 0.06). More complaints on three of the eight Everyday Memory items and three of the nine Everyday Language items were associated with a decline in executive function (Interaction estimate=-0.021 to -0.012, p=0.002 to 0.04). These findings suggest that specific complaints across several cognitive domains are associated with diagnostic conversion. Specific complaints in the domains of Everyday Memory and Language are associated with a decline in both episodic memory and executive function. Increased monitoring and treatment of individuals with these specific SCD may be warranted.

Keywords: alzheimer’s disease, dementia, memory complaints, mild cognitive impairment, risk factors, subjective cognitive decline

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Authors: Abdulai Afolabi Ahmed

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The research was undertaken to examine the influence of sports facilities, equipment, and nutrition on athletes' performance in West-Africa Universities Games (WAUG) with the objectives of finding the areas of success and failure. Relevant literatures were reviewed. The survey research design was adopted for the study. Availability of facilities, equipment and nutrition questionnaire (AFENQ) was administered on hundred (n-100) participants - athletes from five Nigerian Universities from South-West, Nigeria which included Federal University of Technology, Akure, Adekunle Ajasin University, Akungba-Akoko, Lagos State University, Oyo, Olabisi Onabanjo University Ago-Awoye and Ekiti State University, Ado Ekiti. Nigeria. The tests re-test reliability value obtained from the instrument using Pearson Product Moment Correlation co-efficient of 0.86 was used to analyze the result. While the questionnaire collected was subjected to influential descriptive statistics of multiple regression to analyse the data. The results of the data showed that facilities, equipment, and nutrition variables when taken together effectively predict the performance of the athletes during WAUG competitions. The implication is that sports organizers should provide sports resources for the improved performance of the athletes, and that, university managers should employ nutritionist to plan and prepare food for the university athletes before and after major competitions.

Keywords: athletes, equipment, extramural, influence, nutrition, performance

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Authors: Mohamed M. El-heweity, Ahmed Shamel Fahmy, Mostafa Shawky, Ahmed Sherif

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Cold-formed steel (CFS) lipped channel sections are popular as load-bearing members in building structures. These sections are used in the construction industry because of their high strength-to-weight ratio, lightweight, quick production, and ease of construction, fabrication, transportation, and handling. When those cold formed sections with high slenderness ratios are subjected to compression bending, they do not reach failure when reaching their ultimate bending stress, however, they sustain much higher loads due stress re-distribution. Hence, there is a need to study the sectional nominal capacity of CFS lipped channel beams with different web openings subjected to pure bending and uniformly distributed loads. By using finite element (FE) simulations using ANSYS APDL for numerical analysis. The results were verified and compared to previous experimental results. Then a parametric study was conducted and validated FE model to investigate the effect of different openings shapes on their nominal capacities. The results have revealed that CFS sections with hexagonal openings and intermediate notch can resist higher nominal capacities when compared to other sectional openings.

Keywords: cold-formed steel, nominal capacity, finite element, lipped channel beam, numerical study, web opening

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Authors: Helena Susana Afonso Alves, Natália Maria Rafael Canadas, Ana Maria Rodrigues

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We examined the impact of governance rules on information asymmetry, using the turnover ratio and the bid-ask spread as proxies for the information asymmetry. We used a SEM model and analyzed the indirect relations through the voluntary disclosure of information and the organizational performance. We built a voluntary disclosure index based on the information firms provided in their annual reports and divided the governance characteristics in two constructs: directors’ and supervisors’ structures and ownership structure. We concluded that the ownership structure exerts a direct influence on share price and share liquidity, Otherwise, the directors’ and supervisors’ structures exert an indirect influence, through the organizational performance and the voluntary disclosure of information. The results also show that for firms with high levels of disclosure the bid-ask spread is lower. However, in firms with a high ownership concentration investors tend to increase the bid-ask spreads and trade less, which, in this case, reduces the liquidity of the stock. The failure to find the relationship between voluntary disclosure of information and the turnover ratio shows us that the liquidity of shares is more related to the greater or lesser concentration of shareholders, with the performance of their companies than with the access to information. Moreover, it is clear that the role that information disclosure plays is mainly at the level of price formation.

Keywords: corporate governance, information asymmetry, voluntary disclosure, structural equation modelling, SEM

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Authors: Margarida Porfírio Tomás, Paula Pereira, José Manuel Palma Oliveira

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The decline in employment rates across sectors like industry and construction is exacerbated by an aging workforce. This has far-reaching implications for the economy, including skills gaps, labour shortages, productivity challenges due to physical limitations, and workplace safety concerns. To sustain the workforce and pension systems, technology plays a pivotal role. Robots provide valuable support to human workers, and effective human-robot interaction is essential. FORTIS, a Horizon project, aims to address these challenges by creating a comprehensive Human-Robot Interaction (HRI) solution. This solution focuses on multi-modal communication and multi-aspect interaction, with a primary goal of maintaining a human-centric approach. By meeting the needs of both human workers and robots, FORTIS aims to facilitate efficient and safe collaboration. The project encompasses three key activities: 1) A Human-Centric Approach involving data collection, annotation, understanding human behavioural cognition, and contextual human-robot information exchange. 2) A Robotic-Centric Focus addressing the unique requirements of robots during the perception and evaluation of human behaviour. 3) Ensuring Human-Robot Trustworthiness through measures such as human-robot digital twins, safety protocols, and resource allocation. Factor Social, a project partner, will analyse psycho-physiological signals that influence human factors, particularly in hazardous working conditions. The analysis will be conducted using a combination of case studies, structured interviews, questionnaires, and a comprehensive literature review. However, the adoption of novel technologies, particularly those involving human-robot interaction, often faces hurdles related to acceptance. To address this challenge, FORTIS will draw upon insights from Social Sciences and Humanities (SSH), including risk perception and technology acceptance models. Throughout its lifecycle, FORTIS will uphold a human-centric approach, leveraging SSH methodologies to inform the design and development of solutions. This project received funding from European Union’s Horizon 2020/Horizon Europe research and innovation program under grant agreement No 101135707 (FORTIS).

Keywords: skills gaps, productivity challenges, workplace safety, human-robot interaction, human-centric approach, social sciences and humanities, risk perception

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Authors: Wenxin Mei, Jinhua Sun, Qingsong Wang

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The volume expansion of lithium-ion batteries is mainly induced by intercalation induced stress within the negative electrode, resulting in capacity degradation and even battery failure. Stress generation due to lithium intercalation into graphite particles is investigated based on an electrochemical-mechanical model in this work. The two-dimensional model presented is fully coupled, inclusive of the impacts of intercalation-induced stress, stress-induced intercalation, to evaluate the lithium concentration, stress generation, and displacement intra and inter-particle. The results show that the distribution of lithium concentration and stress exhibits an analogous pattern, which reflects the relation between lithium diffusion and stress. The results of inter-particle stress indicate that larger Von-Mises stress is displayed where the two particles are in contact with each other, and deformation at the edge of particles is also observed, predicting fracture. Additionally, the maximum inter-particle stress at the end of lithium intercalation is nearly ten times the intraparticle stress. And the maximum inter-particle displacement is increased by 24% compared to the single-particle. Finally, the effect of graphite particle arrangement on inter-particle stress is studied. It is found that inter-particle stress with tighter arrangement exhibits lower stress. This work can provide guidance for predicting the intra and inter-particle stress to take measures to avoid cracking of electrode material.

Keywords: electrochemical-mechanical model, graphite particle, lithium concentration, lithium ion battery, stress

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Authors: Loukou Amoin Marie Djedri

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Financing is important for all terrorists – from the largest organizations in control of territories, to the smallest groups – not only for spreading fear through attacks, but also to finance the expansion of terrorist dogmas. These organizations pose serious threats to the international community. The disruption of terrorist financing aims to create a hostile environment for the growth of terrorism and to limit considerably the terrorist groups capacities. The World Bank (WB), together with the International Monetary Fund (IMF), decided to include in their scope the Fight against the money laundering and the financing of terrorism, in order to assist Member States in protecting their internal financial system from terrorism use and abuse and reinforcing their legal system. To do so, they have adopted the Anti-Money Laundering /Combating Financing of Terrorism (AML/CFT) standards that have been set up by the Financial Action Task Force. This set of standards, recognized as the international standards for anti-money laundering and combating the financing of terrorism, has to be implemented by States Members in order to strengthen their judicial system and relevant national institutions. However, we noted that, to date, some States Members still have significant AML/CFT deficiencies, which can constitute serious threats not only to the country’s economic stability but also for the global financial system. In addition, studies stressed out that repressive measures are more implemented by countries than preventive measures, which could be an important weakness in a state security system. Furthermore, we noticed that the AML/CFT standards evolve slowly, while techniques used by terrorist networks keep developing. The goal of the study is to show how to enhance the AML/CFT global compliance through the work of the IMF and the WB, to help member states to consolidate their financial system. To encourage and ensure the effectiveness of these standards, a methodology for assessing the compliance with the AML/CFT standards has been created to follow up the concrete implementation of these standards and to provide accurate technical assistance to countries in need. A risk-based approach has also been adopted as a key component of the implementation of the AML/CFT Standards, with the aim of strengthening the efficiency of the standards. Instead, we noted that the assessment is not efficient in the process of enhancing AML/CFT measures because it seems to lack of adaptation to the country situation. In other words, internal and external factors are not enough taken into account in a country assessment program. The purpose of this paper is to analyze the AML/CFT regime in the fight against the financing of terrorism and to find lasting solutions to achieve the global AML/CFT compliance. The work of all the organizations involved in this combat is imperative to protect the financial network and to lead to the disintegration of terrorist groups in the future.

Keywords: AML/CFT standards, financing of terrorism, international financial institutions, risk-based approach

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Authors: Kobid Panthi, Suttisak Soralump, Suriyon Prempramote

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In June 27, 2014 slope movement was observed in upstream side of Khlong Pa Bon Dam, Thailand. The slide did not have any major catastrophic impact on the dam structure but raised a very important question; why did the slide occur after 10 years of operation? Various site investigations (Bore Hole Test, SASW, Echo Sounding, and Geophysical Survey), laboratory analysis and numerical modelling using SIGMA/W and SLOPE/W were conducted to determine the cause of slope movement. It was observed that the dam had undergone the greatest differential drawdown in its operational history in the year 2014 and was termed as the major cause of movement. From the laboratory tests, it was found that the shear strength of clay had decreased with a period of time and was near its residual value. The cyclic movement of water, i.e., reservoir filling and emptying was coined out to be the major cause for the reduction of shear strength. The numerical analysis was carried out using a modified cam clay (MCC) model to determine the strain softening behavior of the clay. The strain accumulation was observed in the slope with each reservoir cycle triggering the slope failure in 2014. It can be inferred that if there was no major drawdown in 2014, the slope would not have failed but eventually would have failed after a long period of time. If there was no major drawdown in 2014, the slope would not have failed. However, even if there hadn’t been a drawdown, it would have failed eventually in the long run.

Keywords: slope movement, strain softening, residual strength, modified cam clay

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Authors: Qian Li, Shouxiang Lu

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With the rapid increase in electric power use, wire and cable fire occur more and more frequent. The fire smoke has a corrosive effect on the solders, which seriously affects the function of electronic equipment. In this research, the effect of environment relative humidity on corrosion behavior of Sn-0.7Cu solder has been researched under 140 g·m⁻³ polyvinyl chloride (PVC) fire smoke atmosphere. The mass loss of Sn-0.7Cu solder increased with the relative humidity. Furthermore, the microstructures and corrosion mechanism were analyzed by using SEM, EDS, XRD, and XPS. The result shows that Sn₂₁Cl₁₆(OH)₁₄O₆ is the main corrosion products and the corrosion process is an electrochemical reaction. The present work could provide guidance to the risk assessment for electronic equipment rescue after a fire.

Keywords: corrosion, fire smoke, relative humidity, Sn-0.7Cu solder

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Authors: S. Ivanova, K. Ivanov

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Bemitil (2-ethylthiobenzimidazole hydrobromide) is a synthetic adaptogen and actoprotector, with wide-ranging pharmacological activities such as nootropic, antihypoxic, antioxidant, immunostimulant. The intake of Bemitil increases mental and physical performance and could be applied under either normal or extreme conditions. Until 2017 Bemitil was not considered as doping and was used by professional athletes more than 30 years because of its high efficiency and safety. The drug was included in WADA monitoring programme for 2018, and most likely it would be included in WADA Prohibited List for 2019. Usually, a substance/method is included in WADA Prohibited List if it meets any two of the following three criteria: the potential to enhance or enhances sports performance/ potential health risk to the athlete/ violates the spirit of sport. Bemitil has high performance-enhancing potential, but it is also safe- it is controversial whether it should be considered as doping.

Keywords: doping, bemitil, sport, actoprotector

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Authors: John C. Munene, Florence Nansubuga

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The study set out to examine a number of theories that have directly or indirectly implied that words are potent but that the potency depends on the context or practice in which they are utilised. The theories include the Freudian theory of Cathexis, which directly suggests that ambiguous events when named become potent as well as the word that is used to name them. We briefly examine Psychological differentiation, which submit that ambiguity is often a result of failure to distinguish figure from ground. The investigate Prospecting Theory, which suggests that in a situation when people have to make decisions, they have options to utilise intuition or reasoned judgment. It suggests that more often than not, the tendency is to utilise intuition especially when generic heuristics such as representativeness and similarity are available. That usage of these heuristics may depend on lack of a salience or accessibility of the situation due to ambiguity. We also examine Activity Theory, which proposes that meaning of words emerge directly and dialectically from the activities in which they are used. The paper argues that the power of words will depend on either or all of the theories mentioned above. To examine this general proposition we test the utilization of a generic competence framework in a local setting. The assumption is that generic frameworks are inherently ambiguous and lack the potency normally associated with the competence concept in the management of human resources. A number of case studies provide initial supporting evidence for the general proposition.

Keywords: competence, meaning, operationalisation, power of words

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Authors: Philip Robert Alldritt

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The continuing increase in human migration is at crisis levels in all areas of the planet. The causes are varied, and the risks are high for the migrants. Migration has been ongoing since the beginning of human emergence on the planet, but for the first time in our historic memory has the, migration reached this level of critical mass. The causes are many. Climate collapse, economic opportunity, drug cartel activity, political upheaval, and gang wars. Many locations are seemingly “within reach” of the migrants, and the push factors are so loaded with hopelessness that almost anyone would be willing to risk anything to improve their conditions. There is no argument about that mass migrations are occurring and will increase in the future. The solutions to this increase are complex. This paper will examine the causes of migration and attempt to provide some reasonable solutions to mitigate the migrations with equitable outcomes that may guide immigration policy in impacted areas.

Keywords: immigration, crisis, climate, cartels

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Authors: Lara Leite Barbosa, Marco Imperadori

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This article aims to define strategies for applying innovative technology so that housing in regions subject to floods can be more resilient to disasters. Based on case studies of seven amphibious and floating projects, it proposes design guidelines to implement this practice. Its originality consists of transposing a technology developed for fluctuating buildings for housing types in regions affected by flood disasters. The proposal could be replicated in other contexts, endowing vulnerable households with the ability to resist rising water levels after a flood. The results of this study are design guidelines to adapt for houses in areas subject to flooding, contributing to the mitigation of this disaster.

Keywords: amphibious housing, disaster resilience, floating architecture, flood mitigation, post-disaster reconstruction

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Authors: Masoumeh Mofarrah, Amir NahanMoghadam

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Higher oil prices and increasing oil demand are main reasons for great attention to Enhanced Oil Recovery (EOR). Comprehensive researches have been accomplished to develop, appraise, and improve EOR methods and their application. Recently, Artificial Intelligence (AI) gained popularity in petroleum industry that can help petroleum engineers to solve some fundamental petroleum engineering problems such as reservoir simulation, EOR project risk analysis, well log interpretation and well test model selection. This study presents a historical overview of most popular AI tools including neural networks, genetic algorithms, fuzzy logic, and expert systems in petroleum industry and discusses two case studies to represent the application of two mentioned AI methods for selecting an appropriate EOR method based on reservoir characterization infeasible and effective way.

Keywords: artificial intelligence, EOR, neural networks, expert systems

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Authors: Rayed Alyousef, Tim Topper, Adil Al-Mayah

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Many of the reinforced concrete structures subject to cyclic load constructed before the modern bond and fatigue design code. One of the main issue face on exists structure is the bond strength of the longitudinal steel bar and the surrounding concrete. A lap splice is a common connection method to transfer the force between the steel rebar in a reinforced concrete member. Usually, the lap splice is the weak connection on the bond strength. Fatigue flexural loading imposes severe demands on the strength and ductility of the lap splice region in reinforced concrete structures and can lead to a brittle and sudden failure of the member. This paper investigates the effect of different concrete covers on the fatigue bond strength of reinforcing concrete beams containing a lap splice under a fatigue loads. It includes tests of thirty-seven beams divided into three groups. Each group has beams with 30 mm and 50 mm clear side and bottom concrete covers. The variables that were addressed where the concrete cover, the presence or absence of CFRP or GFRP sheet wrapping, the type of loading (monotonic or fatigue) and the fatigue load ranges. The test results showed that an increase in the concrete cover led to an increase in the bond strength under both monotonic and fatigue loading for both the unwrapped and wrapped beams. Also, the FRP sheets increased both the fatigue strength and the ductility for both the 30 mm and the 50 mm concrete covers.

Keywords: bond strength, fatigue, Lap splice, FRp wrapping

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Authors: Bistra Kunovska, Kremena Ivanova, Jana Djounova, Desislava Djunakova, Zdenka Stojanovska

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The carcinogenic effects of radon as a radioactive noble gas have been studied and show a strong correlation between radon exposure and lung cancer occurrence, even in the case of low radon levels. The major part of the natural radiation dose in humans is received by inhaling radon and its progenies, which originates from the decay chain of U-238. Indoor radon poses a substantial threat to human health when build-up occurs in confined spaces such as homes, mines and caves and the risk increases with the duration of radon exposure and is proportional to both the radon concentration and the time of exposure. Tourist caves are a case of special environmental conditions that may be affected by high radon concentration. Tourist caves are a recognized danger in terms of radon exposure to cave workers (guides, employees working in shops built above the cave entrances, etc.), but due to the sensitive nature of the cave environment, high concentrations cannot be easily removed. Forced ventilation of the air in the caves is considered unthinkable due to the possible harmful effects on the microclimate, flora and fauna. The risks to human health posed by exposure to elevated radon levels in caves are not well documented. Various studies around the world often detail very high concentrations of radon in caves and exposure of employees but without a follow-up assessment of the overall impact on human health. This study was developed in the implementation of a national project to assess the potential health effects caused by exposure to elevated levels of radon in buildings with public access under the National Science Fund of Bulgaria, in the framework of grant No КП-06-Н23/1/07.12.2018. The purpose of the work is to assess the radon level in Bulgarian caves and the exposure of the visitors and workers. The number of caves (sampling size) was calculated for simple random selection from total available caves 65 (sampling population) are 13 caves with confidence level 95 % and confidence interval (margin of error) approximately 25 %. A measurement of the radon concentration in air at specific locations in caves was done by using CR-39 type nuclear track-etch detectors that were placed by the participants in the research team. Despite the fact that all of the caves were formed in karst rocks, the radon levels were rather different from each other (97–7575 Bq/m3). An assessment of the influence of the orientation of the caves in the earth's surface (horizontal, inclined, vertical) on the radon concentration was performed. Evaluation of health hazards and radon risk exposure causing by inhaling the radon and its daughter products in each surveyed caves was done. Reducing the time spent in the cave has been recommended in order to decrease the exposure of workers.

Keywords: tourist caves, radon concentration, exposure, Bulgaria

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Authors: W. Nataniel, B. Lima, J. Manoel, M. P. Filho, H. Marcos, Oliveira Mauricio, P. Ferreira

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Headed reinforcement bars are increasingly used for anchorage in concrete structures. Applications include connections in composite steel-concrete structures, such as beam-column joints, in several strengthening situations as well as in more traditional uses in cast-in-place and precast structural systems. This paper investigates the reduction in the ultimate tensile capacity of embedded cast-in headed anchors due to concrete cracking. A series of nine laboratory tests are carried out to evaluate the influence of cracking on the concrete breakout strength in tension. The experimental results show that cracking affects both the resistance and load-slip response of the headed bar anchors. The strengths measured in these tests are compared to theoretical resistances calculated following the recommendations presented by fib Bulletin no. 58 (2011), ETAG 001 (2010) and ACI 318 (2014). The influences of parameters such as the effective embedment depth (h_ef), bar diameter (d_s), and the concrete compressive strength (f_c) are analysed and discussed. The theoretical recommendations are shown to be over-conservative for both embedment depths and were, in general, inaccurate in comparison to the experimental trends. The ACI 318 (2014) was the design code which presented the best performance regarding to the predictions of the ultimate load, with an average of 1.42 for the ratio between the experimental and estimated strengths, standard deviation of 0.36, and coefficient of variation equal to 0.25.

Keywords: cast-in headed anchors, concrete cone failure, uncracked concrete, cracked concrete

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Authors: Mokopane Charles Marakalala

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Research shows that mobile fraud has grown exponentially in South Africa during the lockdown caused by the COVID-19 pandemic. According to the South African Banking Risk Information Centre (SABRIC), fraudulent online banking and transactions resulted in a sharp increase in cybercrime since the beginning of the lockdown, resulting in a huge loss to the banking industry in South Africa. While the Financial Intelligence Centre Act, 38 of 2001, regulate financial transactions, it is evident that criminals are making use of technology to their advantage. Money-laundering ranks among the major crimes, not only in South Africa but worldwide. This paper focuses on the impact of biometric-based solutions in combatting mobile fraud at the South African Risk Information. SABRIC had the challenges of a successful mobile fraud; cybercriminals could hijack a mobile device and use it to gain access to sensitive personal data and accounts. Cybercriminals are constantly looting the depths of cyberspace in search of victims to attack. Millions of people worldwide use online banking to do their regular bank-related transactions quickly and conveniently. This was supported by the SABRIC, who regularly highlighted incidents of mobile fraud, corruption, and maladministration in SABRIC, resulting in a lack of secure their banking online; they are vulnerable to falling prey to fraud scams such as mobile fraud. Criminals have made use of digital platforms since the development of technology. In 2017, 13 438 instances involving banking apps, internet banking, and mobile banking caused the sector to suffer gross losses of more than R250,000,000. The final three parties are forced to point fingers at one another while the fraudster makes off with the money. A non-probability sampling (purposive sampling) was used in selecting these participants. These included telephone calls and virtual interviews. The results indicate that there is a relationship between remote online banking and the increase in money-laundering as the system allows transactions to take place with limited verification processes. This paper highlights the significance of considering the development of prevention mechanisms, capacity development, and strategies for both financial institutions as well as law enforcement agencies in South Africa to reduce crime such as money-laundering. The researcher recommends that strategies to increase awareness for bank staff must be harnessed through the provision of requisite training and to be provided adequate training.

Keywords: biometric-based solution, investigation, cybercrime, forensic investigation, fraud, combatting

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Authors: Mohammaad Afzal Khan, Ghazi Abdulmalik Ashoor , Fatimah Alanazi, Talal Shamma, Abdullah Altuhami, Hala Abdalrahman Ahmed, Abdullah Mohammed Assiri, Dieter Clemens Broering

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Microvascular injuries during inflammation are key causes of transplant malfunctioning and permanent failure, which play a major role in the development of chronic rejection of the transplanted organ. Inflammation-induced microvascular loss is a promising area to investigate the decisive roles of regulatory and effector responses. The present study was designed to investigate the impact of IL-10 on immunotolerance, in particular, the microenvironment of the allograft during rejection. Here, we investigated the effects of IL-10 blockade/ reconstitution and serially monitored regulatory T cells (Tregs), graft microvasculature, and airway epithelium in rejecting airway transplants. We demonstrated that the blocking/reconstitution of IL-10 significantly modulates CD4+FOXP3+ Tregs, microvasculature, and airway epithelium during rejection. Our findings further highlighted that blockade of IL-10 upregulated proinflammatory cytokines, IL-2, IL-1β, IFN-γ, IL-15, and IL-23, but suppressed IL-5 secretion during rejection; however, reconstitution of IL-10 significantly upregulated CD4+FOXP3+ Tregs, tissue oxygenation/blood flow and airway repair. Collectively, these findings demonstrate a potential reparative modulation of IL-10 during microvascular and epithelial repair, which could provide a vital therapeutic window to rejecting transplants in clinical practice.

Keywords: interleukin -10, regulatory T cells, allograft rejection, immunotolerance

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Authors: Fatimah M. Alshehrei

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For many years, synthetic pesticides have been used to kill pests; due to their toxicity and pollution, they are now a risk to human and environmental health. Lately, biopesticides have emerged as possible substitutes for petrochemical pesticides. The sources of biopesticides are widely accessible, easily biodegradable, have a variety of modes of action, are less expensive, and have little toxicity toward humans and other creatures that aren't the intended targets. Plants, bacteria, and insects are used to create biopesticides, they used in controlling diseases in crops. Microbial pesticides are produced from different microorganisms such as Trichoderma, Bacillus, Pseudomonas, and Beauveria. Also, botanical pesticides have already been commercialized; they are extracted from neem, pyrethrum, azadirachtin, etc. This paper describes biopesticide categories, their sources, mode of action, advantages and disadvantages, and their role in sustainable agriculture.

Keywords: biopesticides categories, formulation, mode of action, pest control

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Authors: Chien-Chih Lin

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This study argues that the optimal diversifications for the maximization of bank value are asymmetrical; they depend on the business cycle. During times of expansion, systematic risks are relatively low, and hence there is only a slight effect from raising them with a diversified portfolio. Consequently, the benefit of reducing individual risks dominates any loss from raising systematic risks, leading to a higher value for a bank by holding a diversified portfolio of assets. On the contrary, in times of recession, systematic risks are relatively high. It is more likely that the loss from raising systematic risks surpasses the benefit of reducing individual risks from portfolio diversification. Consequently, more diversification leads to lower bank values. Finally, some empirical evidence from the banks in Taiwan is provided.

Keywords: diversification, default probability, systemic risk, banking, business cycle

Procedia PDF Downloads 422

Authors: Eoin Kirwan, Christopher Nulty, Declan Browne

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The professional ice hockey season consists of approximately 60 regular season games with periods of fixture congestion occurring several times in the average season. These periods of congestion provide limited time for recovery, exposing the athletes to the risk of competing whilst not fully recovered. Although a body of research is growing with respect to monitoring fatigue, particularly during periods of congested fixtures in team sports such as rugby and soccer, it has received little to no attention thus far in ice hockey athletes. Consequently, there is limited knowledge on monitoring tools that might effectively detect a fatigue response and the magnitude of fatigue that can accumulate when recovery is limited by competitive fixtures. The benefit of quantifying and establishing fatigue status is the ability to optimise training and provide pertinent information on player health, injury risk, availability and readiness. Some commonly used methods to assess fatigue and recovery status of athletes include the use of perceived fatigue and wellbeing questionnaires, tests of muscular force and ratings of perceive exertion (RPE). These measures are widely used in popular team sports such as soccer and rugby and show promise as assessments of fatigue and recovery status for ice hockey athletes. As part of a larger study, this study explored the magnitude of changes in adductor muscle strength after game play and throughout a period of fixture congestion and examined the relationship between internal game load and perceived wellbeing with adductor muscle strength. Methods 8 professional ice hockey players from a British Elite League club volunteered to participate (age = 29.3 ± 2.49 years, height = 186.15 ± 6.75 cm, body mass = 90.85 ± 8.64 kg). Prior to and after competitive games each player performed trials of the adductor squeeze test at 0˚ hip flexion with the lead investigator using hand-held dynamometry. Rate of perceived exertion was recorded for each game and from data of total ice time individual session RPE was calculated. After each game players completed a 5- point questionnaire to assess perceived wellbeing. Data was collected from six competitive games, 1 practice and 36 hours post the final game, over a 10 – day period. Results Pending final data collection in February Conclusions Pending final data collection in February.

Keywords: Conjested fixtures, fatigue monitoring, ice hockey, readiness

Procedia PDF Downloads 125

Authors: Titap Yazicioglu

Abstract:

To examine the results of two different surgery in patients with severe ptosis and poor levator function. The records of 10 bilateral congenital ptosis patients, who underwent Whitnall’s sling surgery on one eyelid and frontalis sling surgery on the other were analyzed retrospectively. All patients had severe congenital ptosis(>4mm) and poor levator function (LF<4mm). Data regarding eyelid position, cosmetic outcomes, and postoperative complications were evaluated. All patients were assessed for a minimum of one year with regard to the amount of correction, residual ptosis and lagophthalmos. The study consisted of 10 patients, with an average age of 9.2±2.4 years. Preoperative diagnosis for all patients was noted as, the average LF was 3.4±0.51mm, vertical lid height was 3.5±0.52 mm and margin reflex distance-1 (MRD-1) was 0.4±0.51mm. The mean vertical lid height was measured as 7.1±0.73 mm in the frontalis sling group and 7.2±0.63 mm in the Whitnall’s sling group at the postoperative 1st month control. However, in patients with Whitnall’s sling, revision was performed with frontalis sling surgery due to failure in vertical lid height in the late postoperative period, and an average of 7.5±0.52 mm was achieved. Satisfactory results were obtained in all patients. Although postoperative lagophthalmitis developed in the frontalis sling group, none of them developed exposure keratitis. Granuloma was observed as sling infection in 2(20%) of the patients. Although Whitnall’s sling technique provides a natural look appearance without interfering with the functional result, we did not find it as successful as frontalis sling surgery in severe ptosis.

Keywords: congenital ptosis, frontalis suspension, Whitnall ligament, complications

Procedia PDF Downloads 92

Authors: Boulis M. Ibrahim, Iordanis A. Kalaitzoglou

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A micro structural pricing model is proposed in which price components account for learning by incorporating changing expectations of the trading intensity and the risk level of incoming trades. An analysis of European carbon futures transactions finds expected trading intensity to increase the information component and decrease the liquidity component of price changes, but at different rates. Among the results, the expected persistence in trading intensity explains the majority of the auto correlations in the level and the conditional volatility of price changes, helps predict hourly patterns in the bid–ask spread and differentiates between the impact of buy versus sell and continuing versus reversing trades.

Keywords: CO2 emission allowances, market microstructure, duration, price discovery

Procedia PDF Downloads 394

Authors: Danielle A. Walker, Kyle L. Johnson, Patrick J. Fox, Jacen S. Moore

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The HIV Continuum of Care has become a universal model to provide context for the process of HIV testing, linkage to care, treatment, and viral suppression. HIV testing is the first step in moving toward community viral suppression. Countries with a lower socioeconomic status experience the lowest rates of testing and access to care. The Democratic Republic of the Congo is located in the heart of sub-Saharan Africa, where testing and access to care are low and women experience higher HIV prevalence compared to men. In the Democratic Republic of the Congo there is only a 21.6% HIV testing rate among women. Because a critical gap exists between a woman’s risk of contracting HIV and the decision to be tested, this study was conducted to obtain a better understanding of the relationship between factors that could influence HIV testing among women. The datasets analyzed were from the 2013-14 Democratic Republic of the Congo Demographic and Health Survey Program. The data was subset for women with an age range of 18-49 years. All missing cases were removed and one variable was recoded. The total sample size analyzed was 14,982 women. The results showed that there did not seem to be a difference in HIV testing by mean age. Out of 11 religious categories (Catholic, Protestant, Armee de salut, Kimbanguiste, Other Christians, Muslim, Bundu dia kongo, Vuvamu, Animist, no religion, and other), those who identified as Other Christians had the highest testing rate of 25.9% and those identified as Vuvamu had a 0% testing rate (p<0.001). There was a significant difference in testing by religion. Only 0.7% of women surveyed identified as having no religious affiliation. This suggests partnerships with key community and religious leaders could be a tool to increase testing. Over 60% of women who had never been tested for HIV did not know where to be tested. This highlights the need to educate communities on where testing facilities can be located. Almost 80% of women who believed HIV could be transmitted by supernatural means and/or witchcraft had never been tested before (p=0.08). Cultural beliefs could influence risk perception and testing decisions. Consequently, misconceptions need to be considered when implementing HIV testing and prevention programs. Location by province, years of education, and wealth index were also analyzed to control for socioeconomic status. Kinshasa had the highest testing rate of 54.2% of women living there, and both Equateur and Kasai-Occidental had less than a 10% testing rate (p<0.001). As the education level increased up to 12 years, testing increased (p<0.001). Women within the highest quintile of the wealth index had a 56.1% testing rate, and women within the lowest quintile had a 6.5% testing rate (p<0.001). This study concludes that further research is needed to identify culturally competent methods to increase HIV education programs, build partnerships with key community leaders, and improve knowledge on access to care.

Keywords: Democratic Republic of the Congo, cultural beliefs, education, HIV testing

Procedia PDF Downloads 274

Authors: Farej Ahmed Emhmmed

Abstract:

Fracture of duplex stainless steels (DSS) was investigated in air and in 3.5 wt % NaCl solution. Tow sets of fatigued specimens were heat treated at 475ºC for different times and pulled to failure either in air or after kept in 3.5% NaCl with polarization of -900 mV/ SCE. Fracture took place in general by ferrite cleavage and austenite ductile fracture in transgranular mode. Specimens measured stiffness (Ms) was affected by the aging time, with higher values measured for specimens aged for longer times. Microstructural features played a role in "blocking" the crack propagation process leading to lower the CTOD values specially for specimens aged for short times. Unbroken ligaments/ austenite were observed at the crack wake. These features may exerted a bridging stress, blocking effect, at the crack tip giving resistance to the crack propagation process i.e the crack mouth opening was reduced. Higher stress intensity factor Kıc values were observed with increased amounts of crack growth suggesting longer zone of unbroken ligaments in the crack wake. The bridging zone was typically several mm in length. Attempt to model the bridge stress was suggested to understand the role of ligaments/unbroken austenite in increasing the fracture toughness factor.

Keywords: stainless steels, fracture toughness, crack keying effect, ligaments

Procedia PDF Downloads 347

Authors: Tonny Ograh, Joshua Ayarkwa, Dickson Osei-Asibey, Alex Acheampong, Peter Amoah

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Theories are used to improve the conceptualization of research ideas. These theories enhance valuable elucidations that help us to grasp the meaning of research findings. Nevertheless, the use of theories to promote studies in green supplier selection in procurement decisions has attracted little attention. With the emergence of sustainable procurement, public procurement practitioners in Ghana are yet to achieve relevant knowledge on green supplier selections due to insufficient knowledge and inadequate appropriate frameworks. The flagrancy of the consequences of public procurers’ failure to integrate environmental considerations into supplier selection explains the adoption of a multi-theory approach for comprehension of the dynamics of green integration into supplier selection. In this paper, the practicality of three theories for improving the understanding of the influential factors enhancing the integration of environmental sustainability into supplier selection was reviewed. The three theories are Resource-Based Theory, Human Capital Theory and Absorptive Capacity Theory. This review uncovered knowledge management, top management commitment, and environmental management capabilities as important elements needed for the integration of environmental sustainability into supplier selection in public procurement. The theoretical review yielded a framework that conceptualizes knowledge and capabilities of practitioners relevant to the incorporation of environmental sustainability into supplier selection in public procurement.

Keywords: environmental, sustainability, supplier selection, environmental procurement, sustainable procurement

Procedia PDF Downloads 159