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Abstract
Control of OHS risks in the mining industry has been attracting increasing attention in recent years. Because of their great diversity in a complex system, hazards can be difficult to identify and classify, especially when system components interact. Risk cannot be managed successfully without comprehensive investigation of all its aspects. A coherent and integrated classification for identifying and categorizing all hazards is currently lacking in mining. We propose an integrated system classification of OHS hazards in mining based on our review of 44 studies retrieved using PRISMA. Considering Canadian and international standards, regulations and conventions, new hazard categories are proposed and hazard prevention is discussed from 12 perspectives: physical, chemical, biological, ergonomic, accident and psychosocial risks, as well as policy, legislation, management, design, geography, and uncertainty, with reference to each of the four phases of a typical mine life cycle, the hazards were shown in a portrait. This paper provides suitable categories based on rational data for creating a portrait in order to OHS hazards prevention in life cycle activity in mine.
Abstract
This paper aims to recognize the effect of material waste on cost increase in Palestinian construction projects. The study used questionnaire survey to achieve its objectives. The target population of the study are constructors and consultants involved in construction projects. The study also predicts the effect of cost overrun on material waste in some construction activities, namely: ceramic and brick works. The collected data were analyzed using statistical analyses. The study has established that among the various factors that affect cost overrun, experience in the line of work, conflicts among project participants, payments delay, and political situation are the key factors. While the analysis revealed that the main material waste factors are: poor site management, using untrained labors, rework due to workers' mistakes, selecting the lowest bidder contractor/subcontractor, and frequent change orders. Data from 55 building projects constructed in the West Bank between 2015 and 2020 were collected to test the relation between material waste and cost increase. Two mathematical models were developed: Model (l) links cost increase and waste in ceramic works. It indicates that if waste increases by 1%, the cost will increase by 1.07%. Model (2) links between cost increase and material waste in brick works. It tells that if waste increases by 1%, cost will increase by 1.25%. R square of value >0.7, for both models, indicates a strong linear relation between cost increase and material waste. This is the first study that predicts the effect of material waste on cost increase in Palestinian construction sector. The study encourages different parties related to construction projects to manage factors of cost overrun and material waste to enhance the sector of construction.
The Legacy of Soviet Monumental and Decorative Art (on the Example of Tselinograd, Republic of Kazakhstan)
A szovjet monumentális és dekoratív művészet hagyatéka (Celinográd, Kazah Köztársaság példáján)
The development of virgin lands (also known as tselina – previously uncultivated or unexplored areas of land, which have not been affected by humans and are typically located in rural or remote regions) has not only boosted the economy but influenced the development of art in Kazakhstan, particularly in Akmolinsk (in 1961 it was renamed Tselinograd, the current name of the city is Astana). Muralists M. Antonyuk and V. Tovtin made a significant contribution to the artistic and aesthetic image of Tselinograd. The purpose of the study is to identify the role of Soviet monumental and decorative art in designing the aesthetics of urban space and to substantiate its historical and cultural value. In this study, the features of stained-glass windows, marquetry, and monumental mosaics of Tselinograd were analysed. Their value as works of art was analysed, the specificities of incorporating national character are described, and their influence on the cultural development of the city is explained. The level of skill of the artists, including the ability to “embed” the artwork in the architectural image of the building is emphasised. The uniqueness of the monumental mosaics of the Soviet period is proved. Conclusions are drawn about their role as agitation. The need to preserve the works of monumental art for future generations is emphasised. This is an important part of the historical period – thoughtless “modernisation” of residential buildings, indifference to and devaluation of the artistic and cultural heritage of the Soviet past are not acceptable.
Abstract
High-performance internal combustion engines are subject to severe torsional vibrations which result from uneven gas and inertial loads. Fatigue damage occurs if the frequency of these undesired oscillations matches the resonance frequency of the crankshaft and the driven engine elements. This phenomenon can be avoided by the application of visco-dampers whose working fluid is high-viscosity silicone oil. Since silicone oil is exposed to a significant amount of heat load during operation, it is essential to calculate the temperature distribution in a relatively easy, quick, and cost-efficient way for lifetime estimation purposes. The aim of this article is to develop a reliable, fast, and accurate finite difference-based numerical method for steady-state thermal calculations for arbitrary damper sections. The developed MATLAB code calculates the temperature field of the damping fluid together with all components in a radial cross-section at given operational conditions. The accuracy of the developed thermal calculation method has been tested in a 3-dimensional – 2-dimensional two-step verification process by finite element and finite volume-based advanced engineering software in ANSYS environment. Furthermore, the original Iwamoto equation available in the literature has been updated to provide more accurate surface temperature results based on the simulations' outcome gained by the finite volume method.
Abstract
Effects of autonomous trucks' different lateral wander modes have been analyzed in this research using a dload subroutine. Two lateral wander modes, a zero-wander mode in which a truck is programmed to follow a predetermined wheel path without any lateral movement and a uniform wander mode, where the truck uniformly distributes itself along the lateral width of the lane, are used. European class A40 truck has been modeled in ABAQUS code. Results show that fatigue life of pavement increases by 1.45 times if a uniform wander mode is used, which corresponds to a decrease in fatigue life of 14 months if a zero-wander mode is used. In case of rutting progression, 40% acceleration of rutting happens under a zero-wander mode. In case of uniform wander mode, rut depth decreases by 1.25 times against the zero-wander mode.
Abstract
The aims of the work is to develop a numerical iced airfoil; quarter round forward ice was tested on NACA 4410 and NACA 0012 airfoils at zero and non-zero angles of attack, and Reynolds numbers equal to (2∙105, 2.4∙105) based on airfoil chord and Mach number 0.04. The two-dimensional steady-state momentum equations with the continuity equation have been solved applying a finite volume method to examine the turbulent flow over a clean and iced airfoil. The cambered airfoil NACA 4410 spends less power than the unsymmetrical airfoil at the same angle of attack. The reported numerical results demonstrated that for airfoil NACA 4410, the drag was increased by 40%, and the lift was reduced by 22%. However, for airfoil NACA 0012, the drag was increased by 43%, and the lift was decreased by 21%.
Abstract
Wastewater treatment systems are important sources of contaminants of emerging substances, including pharmaceuticals, and personal care products. Onsite wastewater treatment systems provide alternative solutions to centralized systems; although they are becoming increasingly popular, little is known about the effect of maintenance on their performance. In the current study, chemical and microbiological parameters in the effluents from two identical on-site wastewater treatment systems were analyzed, one being properly maintained while the other not maintained at all. Taxonomic profiles vastly differed from each other, and organic micropollutants are present at higher concentrations in the effluent of the non-maintained unit. The results highlight the importance of proper maintenance.
Abstract
Ethiopia's government proposes paving existing roads or building modern intersections in cities to reduce maintenance costs. An unimproved signalized intersection at 6° 51′ 47.9″ N and 37° 45′ 50.1″ E is selected for this research. Cost-benefit analysis is used to evaluate the proposed innovative approach to designing and implementing an intersection and to compare whether the new road projects will have an adequate return. This research suggests converting the current intersection into a signalized roundabout to calm traffic. Signalized roundabouts have a higher net present value and a modified internal rate of return than improved signalized crossing intersections. Considering the country's high inflation rate, three scenarios recommend using a signalized roundabout.
Abstract
Geological conditions are an important parameter on hydrological modeling that strongly affects runoff generation processes. They are not usually taken into account in the parameters of hydrological models, especially karst catchments, where water transfers through fissures, cavities, caves, and phreatic channels are regularly discarded in studies because of their nonlinear behavior and the variability of their typology. The study compared using of base flow separation methods in the conditions of karst catchments, where the reference base flow values measured are not available. The base flow separation was realized by various methods and the models available, including BFI+ and WHAT
Abstract
Chinese city growth has transitioned recently. Urban regeneration that fits local conditions has replaced rapid urbanization. City modernization and historic preservation often clash. Qingdao's ancient blocks need preservation and utilization to develop responsibly. This article aims to investigate the design interventions of adaptive reuse using in practical preserved projects. The study intends to give relevant participants interventions to consider while renovating historic districts to make theories, concepts, and plans guide, promote, and constrain the practice. It should also offer practical solutions to historic city renovation issues.
