Engineering Commons^™

Using Neural Networks To Forecast Volatility For An Asset Allocation Strategy Based On The Target Volatility, Youngmin Kim, David Lee Enke

Engineering Management and Systems Engineering Faculty Research & Creative Works

The objective of this study is to use artificial neural networks for volatility forecasting to enhance the ability of an asset allocation strategy based on the target volatility. The target volatility level is achieved by dynamically allocating between a risky asset and a risk-free cash position. However, a challenge to data-driven approaches is the limited availability of data since periods of high volatility, such as during financial crises, are relatively rare. To resolve this issue, we apply a stability-oriented approach to compare data for the current period to a past set of data for a period of low volatility, providing …

Molecular Tetrapods For Optoelectronic Applications, Jianzhong Yang

Chemistry and Chemical Biology ETDs

Most conjugated molecules including polymers and small molecules applied in organic solar cells (OSCs) have linear structures containing multiple aromatic groups connected in series. However, unfavorable film forming ability and grain boundaries both originated from high crystallinity of linear small molecules are detrimental to device performances. Thus, among multi-dimensional structures, tetrapodal molecules are especially interesting owing to their unique ability to mutually interlock, which prevents dislodging and provides high structural stabilities. Such molecular design can also increase absorption cross-sections and provide more extensively percolating pathways for charge transport, making such molecular tetrapods promising in OSCs applications. In my dissertation, I …

Evaluating Soil Properties And Cyclic Loading Effects Of Florida’S Clayey Silty Fine Sand Soils Associated With High Pile Rebound, Ali Fadil M. Omar

Theses and Dissertations

Throughout the state of Florida, pile rebound has been encountered while driving large displacement piles. During periods of excessive rebound, the piles could not achieve further penetration and could require an excessive number of blows to advance the pile into the ground. This phenomenon affecting pile driving is called high pile rebound producing construction delays, higher costs; and may lead to pile damage. A comprehensive experimental program was performed involving the characterization and identifications of the typical soils properties associated with high pile rebound during pile installation. The research focuses on the determination of the relationships between high and no-rebound …

A Robot Platform For Intelligent Ground Vehicle Research, Jihang Li

Theses and Dissertations

This thesis presents a mobile platform developed for further research on the Intellegent Ground Vehicle project which began as a capstone project but without achieving full autonomy. The scope of the current project is to develop Robot Operating System (ROS) based driver libraries to the electronic system and provide application program interfaces (APIs) for higher abstraction level libraries. Prior work had provided a mechanical system and several sensors for the robot. The chassis of the vehicle is fabricated with aluminum tubings and enclosed with aluminum boards to protect internal electronics from environmental conditions. A three-wheel differential drive architecture is used …

Distribution Of Mean Kinetic Energy Around An Isolated Wind Turbine And A Characteristic Wind Turbine Of A Very Large Wind Farm, Gerard Cortina, Marc Calaf, Raul Bayoan Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

An isolated wind turbine and a very large wind farm are introduced into large-eddy simulations of an atmospheric boundary layer. The atmospheric flow is forced with a constant geostrophic wind and a time-varying surface temperature extracted from a selected period of the CASES-99 field experiment. A control volume approach is used to directly compare the transfer of mean kinetic energy around a characteristic wind turbine throughout a diurnal cycle considering both scenarios. For the very large wind farm case, results illustrate that the recovery of mean kinetic energy around a wind turbine is dominated by the vertical flux, regardless of …

Bioaerosol Deposition On An Air-Conditioning Cooling Coil, Yan Wu, Ailu Chen, Irvan Luhung, Elliott T. Gall, Qingliang Cao, Victor Wei-Chung Chang, William W. Nazaroff

Mechanical and Materials Engineering Faculty Publications and Presentations

This study is concerned with the role of a fin-and-tube heat exchanger in modifying microbial indoor air quality. Specifically, depositional losses of ambient bioaerosols and particles onto dry (not cooled) and wet (cool) coil surfaces were measured for different airspeeds passing through the test coil. Total, bacterial and fungal DNA concentrations in condensate water produced by a wet coil were also quantified by means of fluorescent dsDNA-binding dye and qPCR assays. Results revealed that the deposition of bioaerosols and total particles is substantial on coil surfaces, especially when wet and cool. The average deposition fraction was 0.14 for total DNA, …

Smart Power Grid Synchronization With Fault Tolerant Nonlinear Estimation, Xin Wang, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Effective real-time state estimation is essential for smart grid synchronization, as electricity demand continues to grow, and renewable energy resources increase their penetration into the grid. In order to provide a more reliable state estimation technique to address the problem of bad data in the PMU-based power synchronization, this paper presents a novel nonlinear estimation framework to dynamically track frequency, voltage magnitudes and phase angles. Instead of directly analyzing in abc coordinate frame, symmetrical component transformation is employed to separate the positive, negative, and zero sequence networks. Then, Clarke's transformation is used to transform the sequence networks into the αβ …

Saliency Ratio And Power Factor Of Ipm Motors Optimally Designed For High Efficiency And Low Cost Objectives, Peng Zhang, Dan M. Ionel, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

This paper uses formal mathematical optimization techniques based on parametric finite-element-based computationally efficient models and differential evolution algorithms. For constant-power applications, in the novel approach described, three concurrent objective functions are minimized: material cost, losses, in order to ensure high efficiency, and the difference between the rated and the characteristic current, aiming to achieve very high constant-power flux-weakening range. Only the first two objectives are considered for constant-torque applications. Two types of interior permanent magnet rotors in a single- and double-layer V-shaped configuration are considered, respectively. The stator has the typical two slots per pole and phase distributed winding configuration. …

Comparing The Tensile And Compressive Young’S Moduli Of Cortical Bone, Deshawn Hoskins, Meir Barak

The Winthrop McNair Research Bulletin

Various methods have been used in the testing of the mechanical properties of cortical bone, specifically the young’s modulus. However, in the case of the material’s Young’s modulus in compression and tension, there is a significant disagreement among the published findings that may be a result of experimental artifacts. This study attempts to solve the scientific question of whether cortical bone is stiffer in compression or tension and if so to understand why that is. Using small samples taken from the distal portion of the neck of a femur belonging to a young white tailed deer, both the Young’s moduli …

How Do Family Background And Self-Esteem Affect An Individual’S Perception Of Gender-Role Portrayal In Online Advertisements?, Cera T. Crowe, Aimee P. Meader Dr.

The Winthrop McNair Research Bulletin

The purpose of this study is to further understand the relationship of family background and how it affects self-esteem and the perception of gender roles in online imagery. This study focuses on how our history serves as a lens to see gender roles. The schema theory, created by Robert Axelrod, is a model suggesting that people have a “pre-existing assumption about the way the world is organized” (Axelford, 1974). Furthering this theory is Bem's (1981) Gender Schema Theory, which proposes that one's sexual self-concept affects how one structures items in memory. These theories, applied to the understood roles and activities …

Threshold Voltage Defined Switches And Gates To Prevent Reverse Engineering, Ithihasa Reddy Nirmala

USF Tampa Graduate Theses and Dissertations

¹Semiconductor supply chain is increasingly getting exposed to variety of security attacks such as Trojan insertion, cloning, counterfeiting, reverse engineering (RE), piracy of Intellectual Property (IP) or Integrated Circuit (IC) and side-channel analysis due to involvement of untrusted parties. In this thesis, we use threshold voltage-defined switches to design a logic gate that will camouflage the conventional logic gates both logically and physically to resist RE and IP piracy. The proposed gate can function as NAND, AND, NOR, OR, XOR, and XNOR robustly using threshold defined switches. We also propose a flavor of camouflaged gate that represents reduced functionality …

Investigation Of Electric Field–Induced Structural Changes At Fe-Doped Srtio3 Anode Interfaces By Second Harmonic Generation, David Ascienzo, Haochen Yuan, Steven Greenbaum, Thorsten J. Bayer, Russell A. Maier, Jian-Jun Wang, Clive A. Randall, Elizabeth C. Dickey, Haibin Zhao, Yuhang Ren

Publications and Research

We report on the detection of electric field–induced second harmonic generation (EFISHG) from the anode interfaces of reduced and oxidized Fe-doped SrTiO3 (Fe:STO) single crystals. For the reduced crystal, we observe steady enhancements of the susceptibility components as the imposed dc-voltage increases. The enhancements are attributed to a field-stabilized electrostriction, leading to Fe:Ti-O bond stretching and bending in Fe:Ti-O6 octahedra. For the oxidized crystal, no obvious structural changes are observed below 16 kV/cm. Above 16 kV/cm, a sharp enhancement of the susceptibilities occurs due to local electrostrictive deformations in response to oxygen vacancy migrations away from the anode. Differences between …

Time Dependent Effect Of Drilling Slurries On Side Shear Resistance Of Drilled Shafts, Warren Allen

USF Tampa Graduate Theses and Dissertations

Drilled shafts are cylindrical deep foundations constructed by casting fluid concrete into an excavated hole. These elements rely largely on side shear resistance generated by their substantial diameters and lengths to effectively transfer loads. Therefore, an exceptional concrete to soil interface is essential for proper performance of these structures. The FDOT preferred stabilization fluid, bentonite slurry, has been proven to degrade this interface with increased exposure time due to filter cake formation. For this reason, slurry exposure time has been limited to 36 hours by FDOT. Alternately, polymer slurries do not form a filter cake but rather stabilize excavations through …

A Security Analysis Of Cyber-Physical Systems Architecture For Healthcare, Darren Seifert, Hassan Reza

Computer Science Faculty Publications

This paper surveys the available system architectures for cyber-physical systems. Several candidate architectures are examined using a series of essential qualities for cyber-physical systems for healthcare. Next, diagrams detailing the expected functionality of infusion pumps in two of the architectures are analyzed. The STRIDE Threat Model is then used to decompose each to determine possible security issues and how they can be addressed. Finally, a comparison of the major security issues in each architecture is presented to help determine which is most adaptable to meet the security needs of cyber-physical systems in healthcare.

A Study On The Effectiveness Of The Ism Code Through A Comparative Analysis Of Ism And Psc Data, Min-Jung Lee

World Maritime University Dissertations

No abstract provided.

Clinical Narrative Classification Using Discriminant Word Embeddings With Elm, Paula Lauren, Guangzhi Qu, Feng Zhang, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

Clinical Texts Are Inherently Complex Due to the Medical Domain Expertise Required for Content Comprehension. in Addition, the Unstructured Nature of These Narratives Poses a Challenge for Automatically Extracting Information. in Natural Language Processing, the Use of Word Embeddings Are an Effective Approach to Generate Word Representations (Vectors) in a Low Dimensional Space. in This Paper We Use a Log-Linear Model (A Type of Neural Language Model) and Linear Discriminant Analysis with a Kernel-Based Extreme Learning Machine (Elm) to Map the Clinical Texts to the Medical Code. Experimental Results on Clinical Texts Indicate Improvement with Elm in Comparison to Svm …

Material Evaluation: Self Damping Wire Sd/Acsr Conductor Failures, Daniel F. Weyer

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Following numerous 954 ACSR SD Wire failures from 2010 to 2012, Nebraska Public Power District (NPPD) implemented an inspection program to determine the extent of condition for this type of widely used conductor. NPPD transmission system includes over 2000 miles of this particular conductor.

Transmission line splices are installed every 15-20 spans, with failures being located in a span containing a splice. NPPD worked with Kinectrics to complete electromagnetic field inspections for three days in 2013, with retesting performed in 2015. Throughout this inspection of 54 spans of conductor, 36 were found to have deterioration and corrosion.

Over 80% of …

Combined Nonlinear Visualization And Classification: Elmvis++C, Andrey Gritsenko, Anton Akusok, Yoan Miche, Kaj Mikael Björk, Stephen Baek, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

This Paper Presents an Improvement of the ELMVIS+ Method that is Proposed for Fast Nonlinear Dimensionality Reduction. the ELMVIS++C Has an Additional Supervised Learning Component Compared to ELMVIS+, Which is Originally an Unsupervised Method as Like the Majority of the Other Dimensionality Reduction Method. This Component Prevents Samples under the Same Class Being Separated Apart from Each Other. in This Improved Method, the Importance of the Supervised Component Can Be Further Tuned to Have Different Level of Influence. the Test Results on Four Datasets Indicate that the Proposed Improvement Not Only Maintains the Performance of ELMVIS+, But Also is Extremely …

Metal-Organic Frameworks As Potential Platforms For Carbon Dioxide Capture And Chemical Transformation, Wenyang Gao

USF Tampa Graduate Theses and Dissertations

The anthropogenic carbon dioxide (CO₂) emission into the atmosphere, mainly through the combustion of fossil fuels, has resulted in a balance disturbance of the carbon cycle. Overwhelming scientific evidence proves that the escalating level of atmospheric CO₂ is deemed as the main culprit for global warming and climate change. It is thus imperative to develop viable CO₂ capture and sequestration (CCS) technologies to reduce CO₂ emissions, which is also essential to avoid the potential devastating effects in future. The drawbacks of energy-cost, corrosion and inefficiency for amine-based wet-scrubbing systems which are currently used in industry, …

Green Energy Or Nuclear Power Plants, Besnik Skenderi, Diamanta Skenderi

UBT International Conference

World seems to go green regarding the energy, however the cost of green energy is high and as a result of security issues nuclear energy seems to be avoided, while introducing business and outsourcing concepts nuclear energy seems to be solution.

The Design Of An Extradosed Bridge, Drilon Rraci, Milan Kuhta

UBT International Conference

Bridges are attractive structures consisting of great interest in both aspects: professional and the general public one. At the end of 19. and start of 20. century, one of the most relevant contributions to bridges engineering has been the introduction of prestressed technique, aiming to be a great solution to the need of controlling stress on elements in bridges. The purpose of this paper is to discuss and analyze the design model and structural behavior of an Extradosed bridge. The strategies and factors that must be considered in the design of an Extradosed bridge are included in this paper. The …

Assessment Of Reinforced Concrete Half Joint According To En -1992-1-1, Xhemshir Mulliqi

UBT International Conference

A half-joint is a particular type of RC structure .When using precast beams in reinforced concrete frame structures, dapped beams ends are often required in the bearing area to keep the floor structure as thin as possible. The arrangement and detailing of the reinforcement is an important factor in the performance of a half-joint. For pre-tensioned members, the prestressing force and tendons should be ignored, but for post-tensioned members the prestressing force should be considered as an external force acting on the half-joint. This paper aims to calculate dapped beam ends according to the EN 1992-1-1.

Effects Of Sustainable Materials In Construction, Environment And Health, Muhamet Ahmeti, Mimoza Sylejmani, Vlora Aliu

UBT International Conference

In this paper it is presented a definition of sustainable construction from ecological aspect, characterized by reducing the impact of different materials in the environment during construction, but also during the whole lifetime of use of buildings. To assess the impact of materials on health and environment is necessary to examine all phases from beginning of the materials manufacturing till the insertion to the construction, including the use of natural resources for the production of construction products, necessary energy for production, amount of release and CO2 emissions (carbon dioxide) in different stages, methods of construction, use of construction and in …

Radial Structure Graph Based Mathematical For Large Distribution Networks, Ines Bula, Valmir Hoxha, Edin Bula

UBT International Conference

In the modern electrical distribution network and utility companies a steady increase in the need for high quality and safe delivery of electricity to consumers is evident, which requires an adequate distribution network, that is a network with high quality voltage and low loss of energy, with a small number of failures and equipment failure , etc. In this paper is proposed a way of representing the mathematical model of distribution networks. For calculations of energy applications, the best way for representation distribution network is in form of graph of the radial structure. By presenting the distribution network in the …

The Neutralization Of Water Polution, Afrim Osmani

UBT International Conference

One of the biggest sources of pollution land and water are industrial waste waters. At section of zinc industry in complex Trepca during the process of zink production acquire(are gained or obtained) wastewater where their negative impact is wider extent of contamination of land with which it comes in contact and in this case comes to the accumulation ions of heavy metals, surface water and then mixing with groundwater and pollution. Directly with vulnerable is Sitnica river, in which contaminated water flows from the industrial unit for the production of Zn, which flows into the Ibar river, which still flows …

General Concept For Strengthening The Reinforced Concrete Column A Wrapping Of Cf Sheet, Florim Istrefi

UBT International Conference

Fiber reinforced polymer (FRP) composites (the combination of two or more materials). Used more often in the defense and aerospace industries, advanced composites are beginning to play the role of conventional materials (commodities) used for load-bearing structural components for infrastructure applications. These unique materials are now being used worldwide for building new structures as well as for rehabilitating in-service structures.

“FRP” is an acronym for fiber reinforced polymers, which some also call fiber reinforced plastics, so called because of the fiber content in a polyester, vinyl ester, or other matrix. Three are commonly used (among others): composite containing glass fibers …

Strengthening The Reinforced Concrete Column With Cf Sheet, Florim Istrefi

UBT International Conference

Fiber reinforced polymer (FRP) composites (the combination of two or more materials). The strengthening of concrete members means using constructional measures to restore or improve their load-carrying capacity, serviceability, durability or fatigue strength.

The effects of strengthening measures can generally be described in quantitative terms and therefore analyzed numerically for reinforced concrete columns designed according to the earlier editions of DIN 1045, ACI Committee 440, 2002, there are some strengthening assignments that fall midway between redesign and sprayed concrete. It is for these projects that wrapping with fiber-reinforced materials is to be recommended. This method has already been used frequently …

Modeling Of Flexural Strength Of Fiber Reinforced Concretes Containing Silica Fume Or Fly Ash By Gep, Mustafa Saridemir, Besian Sinani

UBT International Conference

In this paper, a mathematical equation based on the gene expression programming (GEP) model has been developed to predict the flexural strength (ffs) of steel fiber reinforced concretes (SFRCs) containing silica fume (SF) or fly ash (FA). In order to obtain a mathematical equation of this model, the training, testing and validation sets using the experimental results for 175 specimens produced with 118 different mixtures were gathered from different literatures. The data used in the input variables of GEP model are arranged in a format of eleven input parameters that cover the age of specimen, the amounts of concrete mixtures …

Effect Of The Opening In Flat Slabs On Punching Shear Resistance According To En 1992-1-1:2004, Xhemshir Mulliqi

UBT International Conference

After the war in Kosovo is highlighted by the construction of reinforced concrete buildings with flat slabs with no beams and no enlarged column heads .These slabs are subjected to punching shear failure of slab-column connections. Load concentration around the column head generally leads to increased stresses which cannot be absorbed solely in thin slab thicknesses. The punching shear strength is an extremely significant parameter for the design of flat slabs. Solution of architecture often imposes the necessity of openings near the columns .In this paper will examine the effect of openings in different positions and with different dimensions in …

Prediction Of Punching Shear Capacity Of Two-Ways Frp Reinforced Concrete Slabs, Ilker Fatih Kara, Besian Sinani

UBT International Conference

An innovative solution to the corrosion problem is the use of fiber-reinforced polymer (FRP) as an alternative reinforcing material in concrete structures. In addition to the non corrodible nature of FRP materials, they also have a high strength-to-weight ratio that makes them attractive as reinforcement for concrete structures. Extensive research programs have been carried out to investigate the flexural behavior of concrete members reinforced with FRP reinforcement. On the other hand, the shear behavior of concrete members, especially punching shear of two-way slabs, reinforced with FRP bars has not yet been fully explored. The existing provisions for punching of slabs …