113 research outputs found

    Automated Generation and Visualization of Initial Construction Schedules from Building Information Models

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    Recent advances in digital technology have had a significant influence on the quality and speed of sharing and communicating project information in the architecture, engineering, and construction (AEC) industry. The process of acquiring the design intent in order to develop and communicate project schedules, as critical components of project delivery, have similarly been benefitting from such progress. With the relatively recent techniques of Building Information Modeling (BIM) and its capability to integrate the facility design with its construction schedule, meaningul strides have been made in improving the information flow and eventually visualizing the final schedule in 4D. However, the need for faster and more efficient ways of generating both the schedule and its 4D visualization has been growing as it directly impacts the overhead cost, and hence the bottomline, of projects. Lack of direct integration and logical interoperability between the various computer systems used for these processes deprives the industry of the power of synergy that could have resulted from such explicit assimilation of the product and process models and their respective sub-processes. This research develops an approach that interprets 3D building information models into a source of direct input information to generate initial construction schedules for commercial building projects, which ultimately leads to automated visualization of the produced schedule in 4D BIM. By integrating an intermediate product model and generically predefined activities at domains level, it generates initial activities that capture the scope of the work in the design. The method also incorporates semi-automated sequencing algorithms that take into account the logic of support in structural construction and other factors related to work access and user preferences. The methodology has been implemented in a computer application built to substantiate its feasibility and then evaluated with the help of volunteer professionals in the industry by using test cases. The implementation and the tests conducted demonstrated that the developed methodology is feasible and can be considered as a step forward towards complete automation in the industry, while there are still various aspects open for improvement

    Evaluation of Biocontrol Agent and Wheat Straw Mulch on Yield and Yield Components of Groundnut (Arachis hypogaea L.) Genotypes in Central Tigray, Northern Ethiopia

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    Groundnut (Arachis hypogaea L.) is the 13th and 4thmost important food and oil seed crops in the world. Groundnut is a source of vitamin E. However, due to low soil fertility, drought stress, fungal diseases and lack of appropriate management, production has been constrained qualitatively and quantitatively in the study area. Trichoderma harzianum and Wheat straw mulch could increase the growth performance of groundnut and soil moisture content at maturity and near harvest to overcome terminal drought stress. Therefore, a field experiment was conducted in Rama, Central Zone of Tigray, northern Ethiopia, to evaluate the effects of wheat straw mulch and T. harzianum on yield and yield components of groundnut genotypes (ICGV00308, ICIAR19BT, Werer-961 and Rama local). The treatments were arranged in factorial randomized complete block design (RCBD) with three replications. Results showed that groundnut genotypes, T. harzianum and wheat straw mulch highly significantly (p<0.01) affected plant height with the tallest plant height 25.40, cm was recorded from Rama local while the shortest 23.15cm from ICGV00308.The highest (37.06) mean number of seeds per plant was obtained from ICGV00308 treated with wheat straw mulch, followed by (32.05) and (32.91) from ICIAR19BT treated with wheat straw mulch and Rama local treated with T. harzianum and wheat straw mulch respectively. Higher 28.44 and 24.97 numbers of pods per plant were recorded on ICIAR19BT and ICGV00308 genotypes, respectively that were mulched with wheat straw. ICGV00308 genotype produced the highest seed yield per plant (14.69 g), hundred seed weight (51.00 g) and total seed yield (1.00 t ha-1) as compared to the other genotypes. Keywords: groundnut genotype, T. harzianum and wheat straw mulch. DOI: 10.7176/JBAH/9-13-04 Publication date:July 31st 201

    A Societal Life Cycle Costing of Energy Production: The Implications of Environmental Externalities

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    Alberta’s electricity market is deregulated; consequently, it does not recognize the benefits of renewables. This research applied a novel societal life cycle costing approach to estimate the economic values of environmental damages to society that result from coal and biomass fired electricity generation. Although coal fuel is cheaper to produce electricity, yet its societal life cycle costing (LCC) is significantly higher than bioenergy systems. Mainstreaming of environmental externalities creates market advantages for low carbon energy sources. Coal power plants cause Alberta to lose at least $117.8 billion per annum due to externalities. Ending electricity from coal with wood pellet can save 53.7 billion USD per year. The societal life cycle cost per year of coal power plants in Alberta represents 15.8% of the province’s GDP and 343.7% of the total expenditure on health. The transformative potential presented by carbon pricing toward a cleaner future is limited. Externalities for health and ecosystems should also be priced and included in the retail price of electricity

    Structural performance of a Railway Truss Bridge Design, Fabrication, Fem and Model Testing

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    This thesis focuses on the design, fabrication, and analysis of an aluminum truss bridge. The bridge was designed using theoretical and numerical methods, and then physically fabricated for experimental testing. The results showed that the bridge performed well under various loads, confirming the accuracy of the design and fabrication processes. The use of aluminum as a construction material was found to be advantageous due to its strength-to-weight ratio and corrosion resistance. The study highlights the importance of integrating theoretical analysis, advanced modeling, precise fabrication techniques, and experimental testing for understanding the performance of aluminum truss bridges

    Regional Food Frequency Analysis for Zambian River Basins

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    Civil Engineerin

    STRUCTURAL PERFORMANCE OF A RAILWAY TRUSS BRIDGE MODEL: DESIGN, FABRICATION AND MODEL TESTING.

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    This bachelor's thesis focuses on the design, fabrication, and analysis of a truss bridge made of aluminum metal. The truss bridge is first designed theoretically as 2D truss bridge, and it is redesigned as 3D and optimized using SAP2000

    Pullout Resistance of MSE Wall Steel Strip Reinforcement in Uniform Aggregate

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    A wide range of reinforcement-backfill combinations have been used in mechanically stabilized earth (MSE) walls. Steel strips are one type of reinforcement used to stabilize aggregate backfill through anchorage. In the current MSE wall design, pullout capacity of steel strips is evaluated to ensure internal stability of the reinforced mass. The pullout resistance of reinforcement is expressed in terms of a pullout resistance factor that measures the reinforcement-backfill interaction. This pullout resistance factor is commonly determined by performing pullout tests. AASHTO (2012) LRFD Bridge Design and Specifications provides default values of the pullout resistance factor, F*, for strip reinforcement embedded in backfill material with a uniformity coefficient of Cu ≥ 4, where the uniformity coefficient is defined as the ratio of the particle size at 60% finer to that at 10% finer. However, for backfill with a uniformity coefficient, Cu<4, AASHTO (2012) requires project-specific pullout tests. This AASHTO requirement has disqualified a large amount of aggregates produced in Kansas quarries or made them difficult and/or costly to be used in MSE wall construction. To address this problem, an experimental study was undertaken in the Geotechnical Engineering Laboratory at the University of Kansas to examine the effect of aggregate uniformity on pullout resistance of steel strips when the uniformity coefficient of aggregate, Cu<4. Twenty-two pullout tests were carried out on ribbed steel strip reinforcements embedded in six aggregate backfills of uniformity coefficients ranging from 1.4 to 14. The pullout resistance of each reinforcement-backfill combination was investigated under normal stresses of 25, 41 and 69 kPa to simulate reinforcements placed at different depths of fill. Additionally, aggregate backfills with Cu=1.4 and 14 were tested under normal stresses of 103 and 138 kPa to further evaluate the pullout resistance at higher depths. Each test sample was prepared in a consistent way to minimize variations. One of the important influence factor was degree of compaction. The test results demonstrated that the overall trend for all types of aggregates was similar. The uniform aggregates generally behaved in the same way as the well-graded aggregates in terms of pullout resistance. The effect of aggregate uniformity was more obvious in the tests under a lower normal stress than under a higher normal stress. When the normal stress was at 69 kPa, there was no obvious effect of aggregate uniformity. Furthermore, the pullout resistance factors obtained from this study were compared with the default F* values for ribbed strip reinforcement provided by AASHTO (2012). The comparison shows that the pullout resistance factor for ribbed steel strips decreased with depth in the same way as suggested by AASHTO (2012). However, the F* values recommended by AASHTO (2012) are conservative as compared with the test results when aggregate backfills with the uniformity coefficients ranging from 1.4 to 14 were used. In other words, the F* values recommended by AASHTO (2012) can be used to design MSE walls with ribbed steel strips in aggregate backfills of the uniformity coefficient as low as 1.4 provided the backfill meets the AASHTO (2010) requirements

    An investigation into the stereotypical representation of gender roles in advertising : a case study of advertisements from a cross-section of popular South African weekly and bi-weekly newspapers.

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    Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2004.This study was designed to investigate the representation of gender roles in advertisements in popular South African newspapers, namely, the Sunday Times, Rapport, City Press, Post and Ilanga. The literature reviewed shows that media play a role in agenda setting and reinforcing existing gender role stereotypes through advertising. The study focused on the trend towards equal representation of gender roles in advertisements in popular South African newspapers. The research revealed some stereotypical representations of women in the newspapers. Although women were depicted in a variety of professions in the workplace, the advertisements showed some stereotypical depictions. The research also found out that, to some extent, men were depicted performing roles such as beautification and consumption, which have been stereotypically limited to women

    Stress Distributions and Pullout Responses of Extensible and Inextensible Reinforcement in Soil Using Different Normal Loading Methods

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    Copyright ASTM International. All rights reserved; Wed Feb 17 17:01:32 EST 2021. Downloaded by Kansas University, pursuant to License Agreement. No further reproduction authorized.In design of reinforced soil structures, pullout capacity of reinforcement in an anchorage zone is an important parameter for stability analysis. This parameter is generally quantified by conducting laboratory or field pullout tests. In the laboratory pullout test, the reinforcement is embedded in the soil mass at a normal stress, which is commonly applied by a pressurized airbag or a hydraulic jack through a rigid plate, and then a horizontal tensile force is applied to the reinforcement. This article reports an experimental study conducted to evaluate the effect of the load application method using an airbag with and without stiff wooden plates on the vertical stress distribution and the pullout capacities and deformations of extensible (geogrid) and inextensible reinforcement (steel strip) in the soil in a large pullout box. This study monitored the distributions of the vertical earth pressures at the top and bottom of the soil mass in the pullout box, and at the level of reinforcement using earth pressure cells. The measured earth pressures show that the airbag with stiff plates resulted in a nonuniform pressure distribution, whereas the tests with an airbag directly on the soil had an approximately uniform pressure distribution. The nonuniform pressure distribution resulting from the airbag with stiff plates reduced the pullout resistance of the reinforcement as compared with that using the same airbag without stiff plates. The nonuniform pressure distribution effect was more significant for narrow inextensible reinforcements than wide extensile reinforcements. The test results also show that the displacements in the cross section of the same transverse bar were not equal when the normal load was applied through stiff plates
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