This paper focuses on Load distribution factors for horizontally curved composite concrete-steel girder bridges. The finite-element analysis software“SAP2000” is used to examine the key parameters that can influence the distribution factors for horizontally curved composite steel
girders. A parametric study is conducted to study the load distribution characteristics of such bridge system due to dead loading and AASHTO truck loading using finite elements method. The key parameters considered in this study are: span-to-radius of curvature ratio, span length, number of girders, girders spacing, number of lanes, and truck loading conditions. The results have shown that the curvature is the most critical factor which plays an important role in the design of curved girders in horizontally curved composite bridges. Span length, number of girders and girder spacing generally affect the values of the moment distribution factors. Moreover, present study reveals that AASHTO Guide criterion to treat curved bridges with limited curvature as straight one is conservative. Based on the data generated from the parametric study, sets of empirical equations are developed for the moment distribution factors for straight and curved steel I-girder bridges when subjected to the AASHTO truck loading and due to dead loading.
New Azo ligands HL1 [2-Hydroxy-3-((5-mercapto-1,3,4-thiadiazol-2-yl)diazenyl)-1-naphth aldehyde] and HL2 [3-((1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)diazenyl)-2-hydroxy-1-naphthaldehyde] have been synthesized from reaction (2-hydroxy-1-naphthaldehyde) and (5-amino-1,3,4-thiadiazole-2-thiol) for HL1 and (4-amino-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one) for HL2. Then, its metal ions complexes are synthesized with the general formula; [CrHL1Cl3(H2O)], [VOHL1(SO4)] [ML1Cl(H2O)] where M = Mn(II), Co(II), Ni(II) and Cu(II), and general formula; [Cr(L2)2 ]Cl and [M(L2)2] where M = VO(II), Mn(II), Co(II), Ni(II) and Cu(II) are reported. The ligands and their metal complexes are characterized by phisco- chemical spectroscopic
... Show MoreThe need to create the optimal water quality management process has motivated researchers to pursue prediction modeling development. One of the widely important forecasting models is the sessional autoregressive integrated moving average (SARIMA) model. In the present study, a SARIMA model was developed in R software to fit a time series data of monthly fluoride content collected from six stations on Tigris River for the period from 2004 to 2014. The adequate SARIMA model that has the least Akaike's information criterion (AIC) and mean squared error (MSE) was found to be SARIMA (2, 0, 0) (0,1,1). The model parameters were identified and diagnosed to derive the forecasting equations at each selected location. The correlat
... Show MoreReservoir rock typing integrates geological, petrophysical, seismic, and reservoir data to identify zones with similar storage and flow capacities. Therefore, three different methods to determine the type of reservoir rocks in the Mushrif Formation of the Amara oil field. The first method represents cluster analysis, a statistical method that classifies data points based on effective porosity, clay volume, and sonic transient time from well logs or core samples. The second method is the electrical rock type, which classifies reservoir rocks based on electrical resistivity. The permeability of rock types varies due to differences in pore geometry, mineral composition, and fluid saturation. Resistivity data are usually obtained from w
... Show MoreFlat-plate collector considers most common types of collectors, for ease of manufacturing and low price compared with other collectors. The main aim of the present work is to increase the efficiency of the collector, which can be achieved by improving the heat transfer and minimize heat loss experimentally. Five types of solar air collectors have been tested, which conventional channel with a smooth absorber plate (model I), dual channel with a smooth absorber plate (model II), dual channel with perforating “V” corrugated absorber plate (model III), dual channel with internal attached wire mesh (model Ⅳ), and dual channel with absorber sheet of transparent honeycomb, (model Ⅴ). The dual channel collector used for
... Show MoreThis study investigates the effectiveness of mental games in enhancing shooting accuracy among young basketball players. Initially, baseline shooting accuracy was assessed through tests conducted prior to a three-week intervention involving mental games. A follow-up test revealed a significant improvement in participants' shooting accuracy following the intervention. Given the noticeable differences in the new shooting scores compared to the initial assessments, a second set of pre-intervention tests was conducted. These tests reaffirmed the significant enhancement in shooting accuracy, substantiating the hypothesis that mental games positively affect performance. The findings highlight the importance of these intervention programs
... Show MoreSchiff base N,N'-Bis-(4-dimethylamino-benzylidene)-benzene-1,4-diamine has been synthesized from 4-dimethylaminobenzenaldehyde and benzene-1,4-diamine. The structure of Schiff base was obtained by (C.H.N.) microanalysis, Mass, 1HNMR, FT-IR and UV-Vis spectral methods and thermal analysis. Metal mixed ligand complexes of some metal(II) salts with Schiff base ligand and anthranilic acid were prepared in the molar ratio (1:2:2), (Metal):(SBL)2:(Anthra)2, (SBL)= Schiff base ligand, (Anthra) =anthranilic acid and Metal= Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II). The thermal behaviour (TGA) of the complexes was studied. The prepared complexes identified by using mass, thermal analysis, FT.IR and UV-Vis spectrum methods, on otherwise flame
... Show MoreThe present study aimed to identify the availability of the National Council of Teachers of Mathematics (NCTM) standards in the content of mathematics textbooks at the basic education stage in the Sultanate of Oman. The study used the descriptive-analytical approach, adopting the method of content analysis through using a content analysis tool that included (43) indicators distributed on the four NCTM standards related to the field of geometry, after verifying their validity and reliability. The study population consisted of mathematics textbooks (first and second semesters) for ninth-grade students in the Sultanate of Oman in the academic year 2018/2019, while the sample consisted of Geometry units in the content of those books, which a
... Show MoreThe aim of the research is to reveal the reality of teacher performance evaluation in the Sultanate of Oman in light of some global models. The study followed a qualitative descriptive research design. Seven forms of teacher formative and summative assessments were analyzed. Besides, an analytical template was developed, consisting of six areas related to the teaching performance of teachers. These included: lesson planning and preparation, learning environment, education, professional development, student academic, and community and parental partnership. The study reached a number of results; the most notable is the lack of change of forms for more than a decade despite the rapid development of the educational system in the sultanate in
... Show MoreSince the COVID-19 pandemic began, there have been concerns related to the preparedness of healthcare workers (HCWs). This study aimed to describe the level of awareness and preparedness of hospital HCWs at the time of the first wave.
This multinational, multicenter, cross-sectional survey was conducted among hospital HCWs from February to May 2020. We used a hierarchical logistic regression multivariate analysis to adjust the influence of variables based on awareness and preparedness. We then used association rule mining to identify relationships between HCW confidence in handling suspected
The Gullfaks field was discovered in 1978 in the Tampen area of the North Sea and it is one of the largest Norwegian oil fields located in Block 34/10 along the western flank of the Viking Graben in the northern North Sea. The Gullfaks field came on stream in 1986 and reached a peak of production in 2001. After some years, a decrease in production was noticed due to the decrease in pressure in the well. The goal of this paper is to improve the production of a well located in Gullfaks field by injecting CO2 through coiled tubing. The use of the CO2 injection method is due to the fact that it is a greenhouse gas, and its production in the atmosphere contributes to global warming. It is important to reduce its emission
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