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An Integrated Building Information Model (iBIM) for Design of Reinforced Concrete Structures
No full textThe architecture, Engineering and Construction (AEC) industry involve many disciplines during the life cycle of the building from its conception to its demolition. The civil engineering discipline has many domains related to AEC industry such domains include structural engineering, foundation engineering, construction engineering and materials. The structural engineering domain has many tasks that include modeling, analysis, design and detailing. The disciplines, domains and tasks of the AEC industry are related and often require data and information to be transferred electronically among them and/or across them. This paper presents an integrated Building Information Model (iBIM) for design of reinforced concrete structures. The proposed iBIM and its architecture have a framework similar to that of the Industry Foundation Classes (IFC) with its file-based data exchange standard and its central data base repository. The iBIM will facilitate integration of the structural engineering design tasks for reinforced concrete structures and will partially provide for interoperability among other related application programs. EXPRESS language and UML are used to define and represent the product and process models of the iBIM. A proof-of-concept prototype implementation of the tasks of the integrated structural engineering system that uses the proposed model and architecture was coded using Delphi object-oriented programming environment. An example of a beam object is shown to validate the proposed model. It is concluded that integration of other tasks of the structural engineering domain can be achieved using the proposed iBIM that made full utilization of the object-based modeling techniques and the IFC framework
The Influence of Entrepreneurial Action on Strategic Alignment in New Ventures
No full textThe alignment of IT strategy with business strategy has been among the top concerns of business leaders for several decades (Kappelman et al., 2014; Niederman et al., 1991). This interest from practitioners has stimulated researchers to produce a voluminous body of literature where definitions and dimensions of alignment have been proposed, measures and models have been developed, and antecedents and outcomes have been identified (Chan and Reich, 2007). Interest in alignment is driven by the reality that there are important organizational performance benefits for firms that achieve a high degree of alignment (Gerow et al., 2015). Our purpose in this paper is to examine the development of strategic alignment in the specific context of new ventures
Managers and organizational forgetting: a synthesis
No full textPurpose - This paper evaluated how managers influence accidental and intentional organizational forgetting, i.e., knowledge depreciation, knowledge loss, and unlearning.
Design/methodology/approach - The literature was reviewed based on predetermined search terms to identify peer-reviewed articles published in English and available in full-text format from the EBSCOhost and Google Scholar databases. Empirical and theoretical contributions were included. Additional articles, books, and book chapters were manually selected and included based on recent reviews and syntheses of organizational forgetting work.
Findings - Findings revealed that managers contributed to preventing accidental knowledge depreciation and loss and preserving organizational memory. With respect to intentional forgetting, findings revealed contradictory positions: on the one hand, managers contributed to the disbandment of existing beliefs and frames of reference, but on the other hand, they preserved existing knowledge and power structures.
Research limitations/implications - The study was limited by the accessibility of subscribed journals and databases, research scope, and time span.
Practical implications - This paper provides useful guidelines to managers who need to reduce the disruptive effects of accidental forgetting or plan intentional forgetting, i.e., managed unlearning.
Originality/value - This paper represents a first attempt to review and define the influence of managers on organizational forgetting
Minimizing The State Of Health Degradation Of Li-Ion Battery For Low Earth Orbit Satellites
No full textA Master of Science thesis in Engineering Systems Management by Mahmoud Shareef Lami entitled, “Minimizing the State of Health Degradation Of Li-Ion Battery For Low Earth Orbit Satellites”, submitted in April 2018. Thesis advisor is Dr. Abdulrahim Shamayleh and thesis co-advisor is Dr. Shayok Mukhopadhyay. Soft and hard copy available.Satellites have a tangible impact on our daily lives; they provide us with many services like communication, global positioning etc. Satellites may be sent to space for prolonged periods of time. There are several mission profiles for satellites i.e. low earth orbit (LEO), middle earth orbit (MEO) or geosynchronous orbit (GEO) missions. Batteries on board satellites are expected to deliver the power demand at any time during the period of an eclipse, or when the power received from the solar panel is not sufficient. The focus of this thesis is to develop a mixed integer nonlinear scheduling model that reduces the state of health (SOH) degradation of a battery in a LEO satellite. This will improve the battery lifetime, thus increasing the length of time a LEO satellite can stay in service. The developed model for a LEO satellite is solved separately for meeting three different objectives, which are minimizing the number of battery switches between charging and discharging, minimizing the sum of products of the battery state switches and battery current, and minimizing the total depth of discharge (DOD). In addition to the model, a heuristic approach is developed and compared with the mathematical model. In this endeavor, data are collected for an existing LEO satellite, Nayif-1, in order to analyze the current battery behavior in space and compare it with the developed model and heuristics. Sensitivity analysis is conducted to observe the effects of altering different parameters of the model. The results presented in this thesis show that minimizing the sum of products of the battery state switches and the battery current, yields the best results by enhancing the lifetime of the battery by 8 days and providing 122 more cycles than that observed in the data from Nayif-1, assuming that the DOD of the battery remains constant throughout all orbits. Therefore, based on the main results comparison and sensitivity analysis, it is concluded that the second objective function provides the best enhancement of the battery lifetime for LEO satellites.College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM
Energy Management of a Multi-Source Power System
No full textA Master of Science thesis in Engineering Systems Management by Omar Wasseem Salah entitled, “Energy Management of a Multi-Source Power System”, submitted in May 2018. Thesis advisor is Dr. Abdulrahim Shamayleh and thesis co-advisor is Dr. Shayok Mukhopadhyay. Soft and hard copy available.Many industries are heavily dependent on fossil fuels to carry out their daily operations. The transportation industry alone is responsible for consuming two thirds of the oil used around the world. As fossil fuel deposits deplete, the need for transportation via sustainable energy solutions such as electric vehicles and battery-powered drones is rising. Battery- operated drones are being targeted by the product delivery industry. However, the use of drones is limited due to constraints on their flight time and distance. This work proposes an energy management system consisting of multiple energy sources integrated into a drone, to optimize the switching between the sources, in an effort to increase the drone’s maximum flight time and distance. A mathematical model representing the energy sources in the drone is presented, taking into account the different constraints on the system, i.e. primarily the state of charge of the battery, and super capacitor. In addition to the model, a heuristic approach is developed and compared with the mathematical model. The results generated using both methods are analyzed and compared to a standard mode of the operation of a drone; demonstrating that the dynamic approach provides a superior switching sequence, while the heuristic approach provides the advantage of low computational time. Additionally, the switching sequence provided by the dynamic approach was able to meet the power demand of the drone for all simulations performed and showed that the average power consumption across all sources is minimized. However, switching sequences provided by the heuristic approach and standard mode of operation failed in some simulations. Both the dynamic approach and heuristic approach are also tested on a multi-energy source ground robot built at AUS. The results of the tests are compared to the standard mode of operation of the ground robot; validating that the average power consumption across all sources is minimized by both proposed approaches. Moreover, the concept of scheduling different components in a system to generate the optimal operating sequence, can be used in areas like electric vehicles, and smart homes, by altering the inputs and constraints.College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM
BIM for Energy Modelling of Green Buildings
No full textA Master of Science thesis in Civil Engineering by Haidar E. Al-Haidary entitled, “BIM for Energy Modelling of Green Buildings”, submitted in November 2018. Thesis advisor is Dr. Adil K. Tamimi. Soft and hard copy available.Energy conservation has become a priority for many governments and sustainable building standards such as LEEDS and Estidama. This is largely due to the high energy demand of buildings and the rising concerns over the impact fossil-fuel-generated electricity has on the environment. With buildings consuming up to 40% of global energy, the demand for energy-efficient buildings has steadily increased. This study employs the Building Information Modelling (BIM) technology namely Autodesk Revit and the energy modelling software, IES-VE, to analyze the effectiveness of passive design measures such as the building’s orientation and external envelope on its energy consumption. The analysis was performed on a case-study office building and both thermal imaging and the experimental measurement of the building envelope’s U-value were conducted to assist the investigation. The study proves that with just basic knowledge about the HVAC system, the building can be modelled to within 3% of the actual consumption when comparing the colder months. The case-study building was also found to have an EUI of 357.8 kWh/m²/yr according to the model’s consumption, this is relatively lower than the actual EUI of the building of 411.2 kWh/m²/yr obtained using the building’s total estimated consumption. Furthermore, the total savings achieved by increasing the insulation levels of the external wall, adding 100 mm of insulation to the slab on grade, fitting high performance windows, and optimizing the orientation of the building, was 2.77%. The maximum savings achieved from any one efficiency measure, however, was about 1.6%, achieved when using high-performance glazing. It was also shown that although the case-study building had no thermal bridges, all thermal bridges detected on other buildings were about 2°C different from the insulated elements. The study also showed that the U-value calculated by the IES VE software was 0.2354 W/m²K, differing by 31% when compared to the 0.339 W/m²K as measured in-situ. The study finally concludes that a modern office building gains little benefit from retrofit measures that minimize heat gain, however, the framework of BIM, IR camera, and in-situ U-value measurement proved effective.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Shear Capacity of Fiber Reinforced Lightweight Concrete
No full textA Master of Science thesis in Civil Engineering by Mariam Hesham El Shazly entitled, “Shear Capacity of Fiber Reinforced Lightweight Concrete”, submitted in November 2018. Thesis advisor is Dr. Sherif Yehia. Soft and hard copy available.In this study, shear capacity of fiber reinforced High-strength Lightweight Self Consolidated Concrete (HSLWSCC) was investigated. Lightweight aggregate, size 4- 8 mm coarse aggregate, was utilized in the evaluation. Steel (3D and 5D), synthetic and hybrid fibers (mix of steel (5D) and synthetic fibers) with a volume fraction of 0.75 % were added to the concrete matrix to prepare eight beams. In addition, four beams were prepared without fibers as control specimens. The twelve beams were prepared to cover the following six categories: 1) lightweight concrete (ALWSCC); 2) lightweight with partial normal-weight coarse-aggregate replacement (PRLWSCC); 3) lightweight with partial replacement and 3D steel fiber; 4) lightweight with partial replacement and 5D steel fiber; 5) lightweight with partial replacement and synthetic fiber; and 6) lightweight with partial replacement and hybrid fibers (mix of steel (5D) and synthetic fibers). The aim of the experimental program was to evaluate the effect of: 1) the normal-weight coarse-aggregate replacement; 2) the addition of fibers and 3) the steel fiber configuration on the shear capacity of lightweight concrete. It was concluded that the 12% replacement ratio of normal weight aggregate has insignificant effect on the shear capacity of the ALWSCC beams. The addition of the fibers showed a great enhancement in the ultimate load in the range of 91.6% to 137% compared to that of the control specimens (PRLWSCC). Furthermore, the fiber reinforced concrete beams showed improved crack distribution, post cracking and ductile behavior. The improvement was influenced by the fiber type and configuration. The experimental results of the four control beams were compared to the corresponding predicted values from the American, the Canadian and the European codes. It was concluded that, the Euro code, followed by the Canadian code, are better matching the experimental results in this investigation as compared to the ACI code. Moreover, the results of the fiber-reinforced beams were compared with the predicted values calculated from the ACI modified equation and previously proposed equations by other researchers, that accounts for the fiber effect. It was found that the ACI modified equation best matches the experimental results of the fiber reinforced concrete beams.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Predicting split decisions of coding units in HEVC video compression using machine learning techniques
No full textIn this work, we propose to reduce the complexity of HEVC video encoding by predicting the split decisions of coding units. We use a sequencedependent approach in which a number of frames belonging to the video being encoded are used for generating a classification model. At each coding depth of the coding units, features representing the coding unit at that particular depth are extracted from both the present and previously encoded coding units. The feature vectors are then used for generating a dimensionality reduction model and a classification model. The generated models at each coding depth are then used to predict the split decisions of subsequent coding units. Stepwise regression, random forest reduction and principal component analysis are used for dimensionality reduction; whereas, polynomial networks and random forests are utilized for classification. The proposed solution is assessed in terms of classification accuracy, BD-rate, BD-PSNR and computational time complexity. Using seventeen video sequences with four different classes of resolution, an average classification accuracy of 86.5% is reported for the proposed classification system. In comparison to regular HEVC coding, the proposed solution resulted in a BD-rate loss of 0.55 and a BD-PSNR of -0.02 dB. The average reported computational complexity reduction is found to be 39.2%
An Intraoral Camera for Supporting Assistive Devices
No full textA Master of Science thesis in Mechatronics Engineering by Muhammad Amin Tily entitled, “An Intraoral Camera for Supporting Assistive Devices”, submitted in December 2018. Thesis advisor is Dr. Hasan Al-Nashash and thesis co-advisor is Dr. Hasan Mir. Soft and hard copy available.Thousands of patients around the globe are affected by paralysis which hinders the fulfilment of their basic needs such as mobility and speech. Several research topics have been dedicated to improve the livelihood of paralytic patients and a small subset of the topics has focused on capturing inputs from the tongue. The tongue is a muscular organ directly connected to the brain through a cranial nerve known as the hypoglossal nerve which is responsible for the motor functions of the tongue. Hence, tongue movements are not affected during spinal cord injuries, which is one of the major causes of paralysis. Given the importance of capturing inputs from the tongue, this research proposes a novel method of using an intraoral camera for this purpose. It discusses the methods used for capturing the images with the help of an Endoscope camera. It explains how the features were extracted in real-time using image processing techniques on each captured frame and how the orientation and position of the tongue was then accurately classified into one of the 11 possible categories to produce specific outputs which could be used by paralytic patients as inputs to any external system. After testing the system with a data entry application, an average of 19.34 correct entries per minute was calculated from 5 different experiments, and an average error rate of 3.96% was obtained, which outperforms systems such as the Resistopalatography and the MouthPad in terms of accuracy.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR