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Study of Sandy Silica Properties in Area of Edree (Libya) and the Possibility of Using in Various Engineering Industries
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作者 Omar Asad Ahmad Mohamed A. A Rawashdeh Omar Musatfa Alomari 《Journal of Environmental Science and Engineering(A)》 2012年第9期1137-1141,共5页
Silica materials are located in various regions of Libya in large quantities and different mining conditions, so the purpose of this study is silica materials in the south-west of the Libyan region Edree in terms of q... Silica materials are located in various regions of Libya in large quantities and different mining conditions, so the purpose of this study is silica materials in the south-west of the Libyan region Edree in terms of quality and the possibility of using in various engineering industries, particularly construction. The results show that the sands of silica presented in Edree area are of a high degree of purity, as the percentage of silicon (SIO2) reached 99.5%, the percentage of impurities was negligible and represented in some chemical elements in different proportions, such as calcium 0.224%, sodium 0.004%, iron 0.0006%, zinc 0.0003%, boron 0.0003%, potassium 0.0001%, manganese 0.0001% and magnesium 0.0001%, making these materials very suitable in the manufacture of all types of glass, crystal and semi-crystalline high-quality without needing any important treatment, as well as its suitability as a refinement in manufacture of templates metal castings in addition to the possibility of use in the manufacture of cement, building materials and as a filler in paint and brick making and sand and concrete elements can also be used in electronic industries. A geological material of silica present in the form of a sequence of layers of clay and thin layers of sand stone and a large stock of high-quality near the surface, making mining operations of the type of surface and reduces the cost of extraction. 展开更多
关键词 Raw materials SILICA IMPURITIES INDUSTRIES treatment building materials.
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Evaluation of Mechanical Properties and Surface Quality of Wood from Bosnia and Herzegovina Exposed to Outdoor Conditions
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作者 Redžo Hasanagić UmejrŠljivo +3 位作者 Leila Fathi Pallavi Gautam Mohsen Bahmani Miha Humar 《Journal of Renewable Materials》 EI CAS 2024年第8期1417-1431,共15页
This study investigated the mechanical properties of beech(Fagus sylvatica L.)and fir(Abies alba)wood from Bosnia and Herzegovina under outdoor exposure.Samples were exposed for 3-month exposure to assess bending stre... This study investigated the mechanical properties of beech(Fagus sylvatica L.)and fir(Abies alba)wood from Bosnia and Herzegovina under outdoor exposure.Samples were exposed for 3-month exposure to assess bending strength,color changes,and surface quality.Results showed outdoor exposure negatively affected mechanical properties,particularly in samples with extended finger joints,causing significant surface cracks in uncoated samples.Beech wood exhibited notable color changes under exposure,with approximately 50%darkening without coating compared to 25%under covered conditions.Coated samples displayed minimal color changes,affirming the efficacy of surface treatment.Fir wood exhibited a roughness of 8.264μm,while beechwood average roughness increased from 6.767 to 13.916μm after exposure,with micro-pore development affecting water performance.Microscopic analysis identified prevalent fungal colonies,including Penicillium,Aureobasidium,Sclerophoma,and Chaetomium,underscoring their role in organic matter decomposition.This study highlights the importance of wood exposure and treatment selection for various applications. 展开更多
关键词 Mechanical properties outdoor conditions cracks wood species
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Effectiveness of two conventional methods for seismic retrofit of steel and RC moment resisting frames based on damage control criteria 被引量:3
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作者 Seyed Bahram Beheshti Aval Hamed Sadegh Kouhestani Lida Mottaghi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第3期537-555,共19页
This study investigates the efficiency of two types of rehabilitation methods based on economic justification that can lead to logical decision making between the retrofitting schemes. Among various rehabilitation met... This study investigates the efficiency of two types of rehabilitation methods based on economic justification that can lead to logical decision making between the retrofitting schemes. Among various rehabilitation methods, concentric chevron bracing(CCB) and cylindrical friction damper(CFD) were selected. The performance assessment procedure of the frames is divided into two distinct phases. First, the limit state probabilities of the structures before and after rehabilitation are investigated. In the second phase, the seismic risk of structures in terms of life safety and financial losses(decision variables) using the recently published FEMA P58 methodology is evaluated. The results show that the proposed retrofitting methods improve the serviceability and life safety performance levels of steel and RC structures at different rates when subjected to earthquake loads. Moreover, these procedures reveal that financial losses are greatly decreased, and were more tangible by the application of CFD rather than using CCB. Although using both retrofitting methods reduced damage state probabilities, incorporation of a site-specific seismic hazard curve to evaluate mean annual occurrence frequency at the collapse prevention limit state caused unexpected results to be obtained. Contrary to CFD, the collapse probability of the structures retrofitted with CCB increased when compared with the primary structures. 展开更多
关键词 steel and RC moment resisting frames seismic retrofitting collapse probability concentric chevron bracing(CCB) cylindrical friction damper (CFD)
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Modeling of Welding Process by Robotic Vision 被引量:1
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作者 Isak Karabegovic Samir Vojic Ermin Husak 《Journal of Mechanics Engineering and Automation》 2011年第2期135-138,共4页
Modeling of welding process by robotic vision is basically a theoretical problem, means mainly on physical problem, and also technological problem. To obtain a good model of welding process by robotic vision, theoreti... Modeling of welding process by robotic vision is basically a theoretical problem, means mainly on physical problem, and also technological problem. To obtain a good model of welding process by robotic vision, theoretical researches are required but also constant experimental researches of several welding processes. Until today researches of welding processes has been based on empirical and detailed experimentation. This paper presents welding process by robotic and automation points of view with application of new technologies. Welding robotic system has been designed with possibility to control and inspect this process. Parameters that should be controlled during the process have been identified to reach desired quality. Figure of control system of welding process by robotic vision is given in this paper. 展开更多
关键词 MODELING WELDING robotic vision control.
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Association between Tobacco Smoke Exposure (Environmental and Direct) and Incidence and Control of Bronchial Asthma 被引量:1
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作者 S. Dashti L. Zare +2 位作者 M. Shahmari F. Dashti A. Dashti 《Open Journal of Nursing》 2018年第2期150-156,共7页
Background: Asthma is a chronic multifactorial disease with high prevalence. Among asthma risk factors, the effect of tobacco smoke exposure on bronchial asthma is still debated. Aim: The aim of this study was to dete... Background: Asthma is a chronic multifactorial disease with high prevalence. Among asthma risk factors, the effect of tobacco smoke exposure on bronchial asthma is still debated. Aim: The aim of this study was to determine the association between environmental and direct tobacco smoke (cigarette and hookah) exposure and incidence and control of bronchial asthma. Materials & Methods: This descriptive study was conducted on 109 patients with asthma referring to Imam Khomeini Hospital in Ardabil city. Asthma Control Questionnaire was used for evaluating of asthma control. Patients’ asthma control was individually evaluated and compared with together with particular attention to history of tobacco smoke exposure. Chi square and Tav-Kendal were used to analyze the data in SPSS15 software. Results: The history of tobacco smoke exposure was found in 31.2% of the 109 patients. Patients with uncontrolled asthma with 60.6% constituted the largest volume of all samples. There was no significant correlation between tobacco smoke exposure and asthma occurrence (P > 0.05), also there was not found significant correlation between tobacco smoke exposure and asthma control (Error coefficient > 0.10). Conclusion: According to the results, history of tobacco (cigarette and hookah) smoke exposure (environmental and direct) has no effect on the asthma occurs and control status. 展开更多
关键词 ASTHMA TOBACCO SMOKE Pollution EXPOSURE
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A Primary Study on Mechanical Properties of Heat-Treated Wood via in-situ Synthesis of Calcium Carbonate
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作者 Dianen Liang Zhenhao Ding +8 位作者 Qilin Yan Redžo Hasanagić Leila Fathi Zi Yang Longhao Li Jianbo Wang Houhua Luo Qian Wang Demiao Chu 《Journal of Renewable Materials》 SCIE EI 2023年第1期435-451,共17页
This study aims to improve the value of fast-growing wood and extend the heat-treated wood utilization using inorganic calcium carbonate(CaCO_(3))crystals via an in-situ synthesis method.CaCl_(2)and Na 2CO_(3)solution... This study aims to improve the value of fast-growing wood and extend the heat-treated wood utilization using inorganic calcium carbonate(CaCO_(3))crystals via an in-situ synthesis method.CaCl_(2)and Na 2CO_(3)solutions with a concentration ratio of 1:1 were successively introduced into the thermally modified poplar wood obtained by steam heat treatment(HT)at 200℃for 1.5 and 3 h,resulting in the in-situ synthesis of CaCO_(3)crystals inside the heat-treated wood.The filling effect was best at the concentration of 1.2 mol/L.CaCO_(3)was uniformly distributed in the cell cavities of the heat-treated wood,and some of the crystals were embedded in the fissures of the wood cell walls.The morphology of CaCO_(3)crystals was mainly spherical and rhombic polyhedral.Three main types of CaCO_(3)crystals were calcite,vaterite,and aragonite.The HT of poplar wood at 200℃resulted in degrading the chemical components of the wood cell wall.This degradation led to reduced wood mechanical properties,including the surface hardness(HD),modulus of rupture(MOR),and modulus of elasticity(MOE).After CaCO_(3)was in-situ synthesized in the heat-treated wood,the HD increased by 18.36%and 16.35%,and MOR increased by 14.64%and 8.89%,respectively.Because of the CaCO_(3)synthesization,the char residue of the 200℃heat-treated wood samples increased by 9.31%and the maximum weight loss rate decreased by 19.80%,indicating that the filling with CaCO_(3)cannot only improve the mechanical properties of the heat-treated wood but also effectively enhance its thermal stability. 展开更多
关键词 Heat treatment poplar wood calcium carbonate in-situ synthesis REINFORCEMENT
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The Possibility of Agricultural Drainage Water Reuse in Agricultural Project
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作者 Omar Asad Ahmad Mohamed A. A1 Rawashdeh 《Journal of Environmental Science and Engineering(A)》 2012年第9期1096-1100,共5页
Agricultural drainage water in Ashkada-Barak agricultural project is a major source of wasted water, which amount to about 35 million liters per day. This huge sum of wasted water cause a formation of pools around the... Agricultural drainage water in Ashkada-Barak agricultural project is a major source of wasted water, which amount to about 35 million liters per day. This huge sum of wasted water cause a formation of pools around the area and therefore a lot of environmental problems such as the proliferation of mosquitoes, and other health problems, while it can be reuse in a variety purposes such as agriculture, fish farming and drinking, so the goal of this research is to study quality of water and determine its suitability. Different samples were taken over a period of year for testing the most important elements of which were estimated concentrations of nitrate, nitrite and ammonia. The results show a presence of high concentrations of nitrogen compounds in studied water. Temperature had been identified as environmental factor dynamically controlled the process of nitrification. 展开更多
关键词 Drainage water wasted SUITABILITY NITRATE NITRITE AMMONIA environmental factor reuse.
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Water Absorption Capacity and Coating Adhesion on Thermally Modified and Not-Modified Spruce Wood(Blue Stained or Free of Blue Stained)
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作者 Demiao Chu Redžo Hasanagić +2 位作者 Leila Fathi Mohsen Bahmani Miha Humar 《Journal of Renewable Materials》 EI 2023年第12期4061-4078,共18页
This study aimed to investigate the water absorption capacity of thermally modified and non-modified spruce and blue-stained spruce wood.The wettability of wood depends on various factors,including its type,density,po... This study aimed to investigate the water absorption capacity of thermally modified and non-modified spruce and blue-stained spruce wood.The wettability of wood depends on various factors,including its type,density,porosity,and surface treatment.Wood can swell and become distorted when exposed to water or humidity,impacting its structural integrity.Hence,it is crucial to consider the water and water vapour uptake in the wood when choosing materials for applications that are likely to be exposed to moisture.Various moisture absorption tests were conducted to assess water absorption capacity,including short-term and long-term water absorption and water vapour absorption.The results showed a significant difference in the long-term exposure to water,which was related to the density of the wood.The study examined the influence of thermal treatment on the physical properties of wood and observed significant variations in mass change due to coating,indicating differences in adhesion among different wood types.Vacuum-treated blue-stained Norway spruce demonstrated higher adhesion(5%–15%)compared to air-treated samples.Furthermore,cohesion tests revealed lower cohesion force in blue-stained Norway spruce(approximately 20%–30%)compared to Norway spruce.The study also used industry-standard tests to investigate the adhesion and cohesion of nano-coatings on wood surfaces.The results provided valuable information on the properties of coatings applied to wood,which is vital in protecting and decorating wood while also providing preventive protection against wood pests,weathering,and mechanical influences.Wood modification in vacuum involves subjecting the wood to a low-pressure environment to remove air and moisture,allowing for deeper and more uniform penetration of treatment chemicals.In contrast,wood modification in air relies on the natural circulation of air to facilitate the absorption of chemical treatments,without the need for a vacuum chamber. 展开更多
关键词 Wood durability long-term exposure moisture absorption WETTABILITY ABSORPTION
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Justifiability Installation of New Types of Window
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作者 Minka Cehic Salah-Eldien Omer 《材料科学与工程(中英文B版)》 2016年第1期40-47,共8页
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Natural Stone in Jordan: Characteristics and Specifications and Its Importance in Interior Architecture
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作者 Mohannad Tarrad Omar Al-Omari Mohammed AL-Rawashdeh 《Journal of Environmental Science and Engineering(B)》 2012年第6期720-727,共8页
Architecture in Jordan characterized by using the most basic raw materials in the natural environment (such as stone, straw and mud etc.). Jordanian designer interacts with natural materials and link these materials... Architecture in Jordan characterized by using the most basic raw materials in the natural environment (such as stone, straw and mud etc.). Jordanian designer interacts with natural materials and link these materials to the local environment and the climatic characteristics of the place. This research focuses on the basic material in construction in Jordan, a substance of natural stone, where the researchers studied the historical relationship between architecture in Jordan and natural stone material, and also studied the properties, specifications, types and methods of formation of this natural material. This research aims to shed light on the modern material of architecture in Jordan and how the architects deal with natural stone and other alternative materials where the architects became underestimate the use of natural stone material and use modern materials far from the architectural heritage and which are sometimes not compatible with the construction environment in Jordan. To conclude from this study the importance of maintaining the continuity of the historical relationship between natural stone and Jordanian architecture, where the study recommends to the possibility of development of use this material through using it in interior architecture to conserve on natural stone as a feedstock in the architecture of Jordan. 展开更多
关键词 Natural stone interior architecture MATERIALS DESIGN
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Local Pulse Wave Velocity Estimation in the Carotids Using Dynamic MR Sequences
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作者 Mohamad Ayham Darwich Francois Langevin Khaldoun Darwich 《Journal of Biomedical Science and Engineering》 2015年第4期227-236,共10页
The current study presents a new protocol for local pulse wave velocity (PWV) measurement using dynamic MR sequences, which have a high temporal resolution (TR < 6 ms). MR images were obtained at two positions alon... The current study presents a new protocol for local pulse wave velocity (PWV) measurement using dynamic MR sequences, which have a high temporal resolution (TR < 6 ms). MR images were obtained at two positions along the common carotid artery, separated by a distance of 5 cm. In each phase of a MR series, carotid region was automatically extracted and then its area distension waveform could be obtained. Sixteen volunteers with no symptoms of cardiovascular diseases were studied. For local PWV estimation, three delay estimation principles were tested and produced the following values: intersecting tangents method (M1): 4.72 ± 1.40 m/s, second derivative method (M2): 4.94 ± 1.68 m/s and cross-correlation method (M3): 5.03 ± 1.17 m/s. The cross-correlation method showed a relative high reliability as its least standard deviation. 展开更多
关键词 Local Pulse Wave Velocity Arterial Elasticity Dynamic Magnetic Resonance Imaging
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Integration of buildings with third-generation photovoltaic solar cells: a review 被引量:1
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作者 Elahe Mirabi Fatemeh Akrami Abarghuie Rezvan Arazi 《Clean Energy》 EI 2021年第3期505-526,共22页
Clean-energy technologies have been welcomed due to environmental concerns and high fossil-fuel costs.Today,photovoltaic(PV)cells are among the most well-known technologies that are used today to integrate with buildi... Clean-energy technologies have been welcomed due to environmental concerns and high fossil-fuel costs.Today,photovoltaic(PV)cells are among the most well-known technologies that are used today to integrate with buildings.Particularly,these cells have attracted the attention of researchers and designers,combined with the windows and facades of buildings,as solar cells that are in a typical window or facade of a building can reduce the demand for urban electricity by generating clean electricity.Among the four generations that have been industrialized in the development of solar cells,the third generation,including dye-sensitized solar cells(DSSCs)and perovskite,is used more in combination with the facades and windows of buildings.Due to the characteristics of these cells,the study of transparency,colour effect and their impact on energy consumption is considerable.Up to now,case studies have highlighted the features mentioned in the building combination.Therefore,this paper aims to provide constructive information about the practical and functional features as well as the limitations of this technology,which can be used as a reference for researchers and designers. 展开更多
关键词 renewable energies building-integrated photovoltaics nano-crystalline dye-sensitized solar cell semi-transparent-based perovskite solar cells ENERGY-SAVING
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Presentation of machine learning methods to determine the most important factors affecting road traffic accidents on rural roads
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作者 Hamid MIRZAHOSSEIN Milad SASHURPOUR +1 位作者 Seyed Mohsen HOSSEINIAN Vahid Najafi Moghaddam GILANI 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2022年第5期657-666,共10页
The purpose of this research was to develop statistical and intelligent models for predicting the severity of road traffic accidents(RTAs)on rural roads.Multiple Logistic Regression(MLR)was used to predict the likelih... The purpose of this research was to develop statistical and intelligent models for predicting the severity of road traffic accidents(RTAs)on rural roads.Multiple Logistic Regression(MLR)was used to predict the likelihood of RTAs.For more accurate prediction,Multi-Layer Perceptron(MLP)and Radius Basis Function(RBF)neural networks were applied.Results indicated that in MLR,the model obtained from the backward method with the correct percent of 84.7%and R2 value of 0.893 was the best method for predicting the likelihood of RTAs.Also,MLR showed that the variables of not paying attention to the front not paying attention to the frontroad ahead,followed byand then vehicle-motorcycle/bike accidents were the greatest problems.Among the models,MLP had a better performance,so that the prediction accuracy of MLR,MLP,and RBF were 84.7%,96.7%,and 92.1%,respectively.MLP model,due to higher accuracy,showed that the variable of reason of accident had the highest effect on the prediction of accidents,and considering MLR results,the variables of not paying attention to the front and then vehicle-motorcycle/bike accidents had the most influence on the occurrence of accidents.Therefore,motorcyclists and cyclists are more prone to accidents,and appropriate solutions should be adopted to enhance their safety. 展开更多
关键词 SAFETY rural accidents multiple logistic regression artificial neural networks
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MODELING DRYING OF A COATED PAPER
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作者 MILAD ASGARPOUR KHANSARY FARZANEH KAZEMI QALEH JOOGH +4 位作者 ASHKAN HOSSEINI JABER SAFARI EDRIS ALLAHYARI NAVID SHABAN ZADEH AHMAD HALLAJI SANI 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2014年第1期148-169,共22页
Drying of a coated paper is modeled and simulated.The paper sheet is assumed to form three zones,and each zone has its own drying mechanism.Coupling of energy and mass balances must be used in order to solve different... Drying of a coated paper is modeled and simulated.The paper sheet is assumed to form three zones,and each zone has its own drying mechanism.Coupling of energy and mass balances must be used in order to solve differential equations.The simulations are carried out in various drying conditions i.e.,only hot air drying,only radiant drying,and mixed hot air-radiant drying.Also the effect of one side and two side assumption on evaporation is studied.Effect of venting air speed and radiant heat source presence and its distance from the drying surface on the drying of a coated paper has been studied.It is found that both distance and venting air speed are inversely related to drying in mixed hot air-radiant drying.Both surfaces participate in evaporation however,during the last time of drying,no difference between the upper and the bottom surfaces exist. 展开更多
关键词 Mathematical modeling coated paper drying hot air drying radiant drying evaporation and penetration
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Estimation of highway capacity under environmental constraints vs.conventional traffic flow criteria:A case study of Tehran
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作者 Hamid Mirzahossein Farshid Safari Erfan Hassannayebi 《Journal of Traffic and Transportation Engineering(English Edition)》 CSCD 2021年第5期751-761,共11页
In this paper,the concept of environmental capacity is developed to identify a convenient maximum traffic volume which will not reduce the life quality of residents.The presented method investigates the idea of traffi... In this paper,the concept of environmental capacity is developed to identify a convenient maximum traffic volume which will not reduce the life quality of residents.The presented method investigates the idea of traffic capacity under environmental constraints by calculating the maximum number of vehicles allowed on roads based on acceptable levels of air and noise pollutants.In this study,the permissible noise pollution level and permissible levels of CO and NOxpollution are considered for determining environmental capacity.Results show the significant difference between environmental capacity and functional traffic capacity,introduced by the highway capacity manual(HCM)as a conventional method for estimating functional capacity.Thus,maximum allowed pollution is considered a constraint on a vehicle flow rate,which shows the proper traffic flow for selected streets in Tehran,Iran’s capital.The paper concludes that traffic capacity under noise and air pollution constraints is much less(approximately one-fourth and one-eighth for noise and air pollution respectively)than the current highway capacity estimated using HCM guidelines.Therefore,to save the cities like Tehran from noise and air pollution,traffic flows should be limited to the level of environmental capacity by implementing some travel demand management(TDM)policies like road pricing. 展开更多
关键词 Traffic engineering Environmental pollutions Environmental capacity estimation Admissible traffic flow Highway capacity manual(HCM)
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Corrigendum to: Integration of buildings with third-generation photovoltaic solar cells: a review
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作者 Elahe Mirabi Fatemeh Akrami Abarghuie Rezvan Arazi 《Clean Energy》 EI 2021年第4期741-741,共1页
This is a correction notice for article zkab031(DOI:https://doi.org/10.1093/ce/zkab031),published on 27 September 2021.In the originally published version of this manuscript,the affili-ation of Rezan Arazi(the third a... This is a correction notice for article zkab031(DOI:https://doi.org/10.1093/ce/zkab031),published on 27 September 2021.In the originally published version of this manuscript,the affili-ation of Rezan Arazi(the third author)was incorrectly written as Department of Architecture;the correct affiliation is Department of Chemistry.Thus,the affiliation of Rezvan Arazi should be'Department of Chemistry,Faculty of Science,Yazd University,Yazd,I.R.Iran'. 展开更多
关键词 DOI CORRECTION INTEGRATION
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