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Full-Text Articles in Engineering

Exploration Of Shared Passenger Urban Air Mobility – Integrated Network Design, Operation Scheduling And System Configuration, Zhiqiang Wu Jul 2023

Exploration Of Shared Passenger Urban Air Mobility – Integrated Network Design, Operation Scheduling And System Configuration, Zhiqiang Wu

USF Tampa Graduate Theses and Dissertations

Urban air mobility (UAM) is an emerging concept proposed in recent years that uses electric vertical take-off and landing vehicles (eVTOLs). UAM is expected to offer an alternative way of transporting passengers and goods in urban areas with significantly improved mobility by making use of low-altitude airspace. Considering the high capital investment of eVTOLs and relative high fee of using UAM passenger service, a viable UAM format is shared passenger service. Such a service is usually station-based, i.e., with vertiport located in popular sites where potential passengers can access. To understand the viability of such use cases, the vertiport owners …


An Anthropology With Human Waste Management: Non-Humans, The State, And Matters Of Care On The Placencia Peninsula, Belize, William Alex Webb Nov 2022

An Anthropology With Human Waste Management: Non-Humans, The State, And Matters Of Care On The Placencia Peninsula, Belize, William Alex Webb

USF Tampa Graduate Theses and Dissertations

The management of human waste is a seldom studied phenomenon in anthropology. Yet across the globe, in countries both rich and poor, it presents pervasive and difficult to tame problems. This dissertation draws on complimentary theories of management and entanglements to explore the practices and processes of organizing human waste on the Placencia Peninsula, Belize. The results illustrate how problems are conditioned and defined by messy relations between institutions, people, technologies, materials, and ecological life.

Fieldwork and analysis for this work was a culmination of years of interdisciplinary collaboration between other anthropologists and engineers at the University of South Florida. …


Towards More Task-Generalized And Explainable Ai Through Psychometrics, Alec Braynen Nov 2022

Towards More Task-Generalized And Explainable Ai Through Psychometrics, Alec Braynen

USF Tampa Graduate Theses and Dissertations

In this work, we propose that adopting the methods, principles, and guidelines of the field of psychometrics can help the Artificial Intelligence (AI) community to build more task-generalizable and explainable AI. Three arguments are presented and explored. These arguments are that psychometrics can help by providing 1) a framework for formulating better datasets, 2) psychometric AI data that can lead to models of generalization in AI, and 3) explainable AI through more informative evaluations.

A review of psychometrics and psychological generalization is performed, along with an overview of evaluation, generalization, and explainability in AI. Various ideas are presented throughout for …


Novel Approach To Integrate Can Based Vehicle Sensors With Gps Using Adaptive Filters To Improve Localization Precision In Connected Vehicles From A Systems Engineering Perspective, Abhijit Vasili Nov 2021

Novel Approach To Integrate Can Based Vehicle Sensors With Gps Using Adaptive Filters To Improve Localization Precision In Connected Vehicles From A Systems Engineering Perspective, Abhijit Vasili

USF Tampa Graduate Theses and Dissertations

Research and development in Connected Vehicles (CV) Technologies has increased exponentially, with the allocation of 75 MHz radio spectrum in the 5.9 GHz band by the Federal Communication Commission (FCC) dedicated to Intelligent Transportation Systems (ITS) in 1999 and 30 MHz in the 5.9 GHz by the European Telecommunication Standards Institution (ETSI). Many applications have been tested and deployed in pilot programs across many cities all over the world.

CV pilot programs have played a vital role in evaluating the effectiveness and impact of the technology and understanding the effects of the applications over the safety of road users. The …


Theory And Algorithms For Systems Optimization, Vahid Mahmoodian Nov 2021

Theory And Algorithms For Systems Optimization, Vahid Mahmoodian

USF Tampa Graduate Theses and Dissertations

This dissertation presents four sets of contributions in the field of theory and algorithms for system optimization. In the first set, we introduce a simulation optimization method for redistributing bikes in a free-floating bike sharing system. The second set of contributions is a framework for batching queries in large databases to optimize the data retrieval time. The third set includes two branch-and-bound algorithms to solve minimum multiplicative programming problems and one branch-and-bound algorithm to solve the maximum form of the mentioned problems. At last, the fourth set presents an approach to fairlyassign delivery tasks in an outsourcing last-mile delivery system …


Constructing Frameworks For Task-Optimized Visualizations, Ghulam Jilani Abdul Rahim Quadri Oct 2021

Constructing Frameworks For Task-Optimized Visualizations, Ghulam Jilani Abdul Rahim Quadri

USF Tampa Graduate Theses and Dissertations

Visualization is crucial in today’s data-driven world to augment and enhance human understanding and decision-making. Effective visualizations must support accuracy in visual task performance and expressive data communication. Effective visualization design depends on the visual channels used, chart types, or visual tasks. However, design choices and visual judgment are co-related, and effectiveness is not one-dimensional, leading to a significant need to understand the intersection of these factors to create optimized visualizations. Hence, constructing frameworks that consider both design decisions and the task being performed enables optimizing visualization design to maximize efficacy. This dissertation describes experiments, techniques, and user studies to …


Data-Driven Studies On Social Networks: Privacy And Simulation, Yasanka Sameera Horawalavithana Jun 2021

Data-Driven Studies On Social Networks: Privacy And Simulation, Yasanka Sameera Horawalavithana

USF Tampa Graduate Theses and Dissertations

Social media datasets are fundamental to understanding a variety of phenomena, such as epidemics, adoption of behavior, crowd management, and political uprisings. At the same time, many such datasets capturing computer-mediated social interactions are recorded nowadays by individual researchers or by organizations. However, while the need for real social graphs and the supply of such datasets are well established, the flow of data from data owners to researchers is significantly hampered by privacy risks: even when humans’ identities are removed, or data is anonymized to some extent, studies have proven repeatedly that re-identifying anonymized user identities (i.e., de-anonymization) is doable …


Adaptive Network Slicing In Fog Ran For Iot With Heterogeneous Latency And Computing Requirements: A Deep Reinforcement Learning Approach, Almuthanna Nassar Jun 2021

Adaptive Network Slicing In Fog Ran For Iot With Heterogeneous Latency And Computing Requirements: A Deep Reinforcement Learning Approach, Almuthanna Nassar

USF Tampa Graduate Theses and Dissertations

In view of the recent advances in Internet of Things (IoT) devices and the emerging new breed of smart city applications and intelligent vehicular systems driven by artificial intelligence, fog radio access network (F-RAN) has been recently introduced for the next generation wireless communications. The capability of F-RAN has emerged to overcome the latency limitations of cloud-RAN (C-RAN) and assure the quality-of-service (QoS) requirements of the ultra-reliable-low-latency-communication (URLLC) for IoT applications. To this end, fog nodes (FNs) are equipped with computing, signal processing and storage capabilities to extend the inherent operations and services of the cloud to the edge. However, …


Longitudinal Trajectory Tracking Analysis For Autonomous Electric Vehicles Based On Pid Control, Hossein Amiri Mar 2021

Longitudinal Trajectory Tracking Analysis For Autonomous Electric Vehicles Based On Pid Control, Hossein Amiri

USF Tampa Graduate Theses and Dissertations

The implementation of autonomous vehicles has huge potential for revolutionizing transportation as we currently know it. All use cases of autonomous vehicles require the vehicle to travel on a pre-specified path. Accurate tracking of this defined trajectory is a crucial aspect of the implementation of autonomous vehicles; a controller system is required to translate this pre- defined trajectory in the form of the throttle, brake, and steering inputs. This project covers the application of a Proportional-Integral-Derivative (PID) controller to achieve longitudinal trajectory tracking of autonomous electric vehicles with stability and accuracy in the CARLA autonomous driving simulation platform. The implemented …


Designing Next-Generation Transportation Systems With Emerging Vehicle Technologies, Zhiwei Chen Nov 2020

Designing Next-Generation Transportation Systems With Emerging Vehicle Technologies, Zhiwei Chen

USF Tampa Graduate Theses and Dissertations

Recent advances in computing and artificial intelligence have enabled the development of various emerging vehicle technologies, e.g., autonomous vehicles (AV) and modular autonomous vehicles (MAV). These technologies bring new scientific and engineering problems challenging transportation researchers and practitioners. This dissertation aims to develop a suite of scalable computational and analytical tools for designing and analyzing next-generation transportation systems with the MAV technologies. Also, we intend to empirically study the system impacts in terms of the quality of service, energy implications, and inequality impacts.

For MAV system design, we develop a methodological framework centering at theoretical properties of the optimal system …


An Inferential Study Of The Potential Consumer Value Of Free Charging For Users Of Public Electric Vehicle Charging Infrastructure, Divyamitra Mishra Oct 2020

An Inferential Study Of The Potential Consumer Value Of Free Charging For Users Of Public Electric Vehicle Charging Infrastructure, Divyamitra Mishra

USF Tampa Graduate Theses and Dissertations

Although there is economic and marketing evidence of consumers assigning additional benefits to free products and bundles, there is limited research into the behavioral consequences of offering public electric vehicle charging for free. Previous exploratory research by Maness and Lin analyzed possible economic and environmental benefits from offering free public charging infrastructure and policy. Their work found that providing free public charging infrastructure could increase plug-in electric vehicle sales and cause decreased reliance on fossil fuels in the personal transportation sector. However, their study assumed the increased value which consumers would place on free charge events. This project proposes to …


Using Optimization Methods For Solving Problems In Sustainable Urban Mobility And Conservation Planning, Zulqarnain Haider Jul 2020

Using Optimization Methods For Solving Problems In Sustainable Urban Mobility And Conservation Planning, Zulqarnain Haider

USF Tampa Graduate Theses and Dissertations

This dissertation considers three separate optimization problems related to sustainable urban and environmental systems. The first problem relates to the nightly relocation and recharging operations for Free-floating electric vehicle sharing (FFEVS) systems. Such operations involve a crew of drivers to move the shared electric vehicles (EVs), and a fleet of shuttles to transport those drivers. Mixed integer programs are used to model the relocation and recharging operations. Two approaches are devised: sequential and synchronized approaches. In the sequential approach, the movement of EVs is first decided, then the routing of shuttles and drivers is determined. In the synchronized approach, all …


Post-Overlay Flexible Pavement Performance Modeling And Its Application In Sustainable Asphalt Overlay Policy Making, Chunfu Xin Apr 2020

Post-Overlay Flexible Pavement Performance Modeling And Its Application In Sustainable Asphalt Overlay Policy Making, Chunfu Xin

USF Tampa Graduate Theses and Dissertations

Highway pavement is a critical component of the highway transportation infrastructure. After the construction of a pavement system, pavement condition will deteriorate over time due to a combination effect of material aging, traffic loading, and environmental impact. To restore the pavement performance and to reduce its adverse effects on public users and environment, asphalt overlay activities are conducted frequently during the service life of a pavement. As a key component that bridges the overlay policies with future pavement performance, economic cost and environmental impact, the forecast accuracy of post-overlay pavement performance model is extremely important. However, most of previous studies …


Game Theory Approaches For Transportation Problems, Mahdi Takalloo Mar 2020

Game Theory Approaches For Transportation Problems, Mahdi Takalloo

USF Tampa Graduate Theses and Dissertations

This dissertation considers three separate game theory problems in transportation. In the first problem, a combinatorial auction market has been proposed for fractional ownership of autonomous vehicles. The proposed combinatorial auction has two unique features. First, the items are continuous time slots defined by bidders and second, the spatial information of bidders has been incorporated so that sharing becomes a viable plan. A conflict-based formulation of the winner determination problem has been proposed, for which an effective solution approach based on a heuristic and a maximal-clique based relaxation has been presented. The second part of the dissertation examines a pessimistic …


Trajectory Based Traffic Analysis And Control Utilizing Connected Autonomous Vehicles, Yu Wang Nov 2019

Trajectory Based Traffic Analysis And Control Utilizing Connected Autonomous Vehicles, Yu Wang

USF Tampa Graduate Theses and Dissertations

Recent scholars have developed a number of stochastic car-following models that have successfully captured driver behavior uncertainties and reproduced stochastic traffic oscillation propagation. While elegant frequency domain analytical methods are available for stability analysis of classic deterministic linear car-following models, there lacks an analytical method for quantifying the stability performance of their peer stochastic models and theoretically proving oscillation features observed in the real world. To fill this methodological gap, this study proposes a novel analytical method that measures traffic oscillation magnitudes and reveals oscillation characteristics of stochastic linear car-following models. We investigate a general class of stochastic linear car-following …


Dynamic Prediction Of Runway Configuration And Airport Acceptance Rate, Yuan Wang Nov 2019

Dynamic Prediction Of Runway Configuration And Airport Acceptance Rate, Yuan Wang

USF Tampa Graduate Theses and Dissertations

Automated prediction of runway configuration and airport capacity is critical for the future generation of air traffic management. In the future aviation industry, multi-sources weather forecast information will be available for air traffic decision-making units; how to use these data efficiently is key for overall efficiency of air traffic management. Currently, air traffic management personnel lack tools to assist them to translate weather forecast data into real-time airport capacity. Runway configurations and AARs of airports in a multi-airport system are determined by different air traffic controller personnel. The lack of synchronization may lead to the loss of efficiency of the …


Statistical Learning Of Biomedical Non-Stationary Signals And Quality Of Life Modeling, Mahdi Goudarzi Jul 2019

Statistical Learning Of Biomedical Non-Stationary Signals And Quality Of Life Modeling, Mahdi Goudarzi

USF Tampa Graduate Theses and Dissertations

Statistical learning is a set of tools for modeling and understanding complex datasets. It is a recently developed area in statistics and blends with parallel developments in computer science and, in particular, machine learning.

The classification of biomedical non-stationary signals such as Electroencephalogram (EEG) is always a challenging problem due to their complexity. The low spatial resolution on the scalp, curse of dimensionality, poor signal-to-noise ratio are disadvantages of working with biomedical signals. EEG signals are unstructured data which needs preprocessing steps to extract informative features which are measurable and predictive. In the first two chapters of this dissertation, EEG …


Statistical Anomaly Detection And Mitigation Of Cyber Attacks For Intelligent Transportation Systems, Ammar Haydari Jun 2019

Statistical Anomaly Detection And Mitigation Of Cyber Attacks For Intelligent Transportation Systems, Ammar Haydari

USF Tampa Graduate Theses and Dissertations

Secure vehicular communication is a critical factor for secure traffic management. Perfect security in intelligent transportation systems (ITS) has solid and efficient intrusion detection systems (IDS). In this paper, we consider false data injection attacks and distributed denial-ofservice attacks (DDoS), especially the stealth low-rate DDoS attacks, targeting the integrity and availability, respectively, in vehicular ad-hoc networks (VANET). Novel statistical intrusion detection and mitigation techniques are proposed for the considered attacks. The performance of the proposed methods are evaluated using a traffic simulator and a real traffic dataset. Comparisons with the state-of-the-art solutions clearly demonstrate the superior performance of the proposed …


Steady State Hydroplaning Risk Analysis And Evaluation Of Unsteady State Effects, Menna Yassin Jun 2019

Steady State Hydroplaning Risk Analysis And Evaluation Of Unsteady State Effects, Menna Yassin

USF Tampa Graduate Theses and Dissertations

Hydroplaning is a major concern on high speed roadways during heavy rainfall events. Hydroplaning tools are widely used by designers to reduce their roadway’s hydroplaning potential, therefore reducing the possibilities of severe crashes. This dissertation presents two methodologies for improving the prediction of hydroplaning potential.

The first phase focused on improving an existing widely used software called PAVDRN. Using multiple datasets from the Florida Department of Transportation, the author filtered the data using specific criteria to leave only truly dynamic hydroplaning crashes. The author then evaluated PAVDRN’s prediction capabilities and assessed its reliability in predicting a hydroplaning crash. Using past …


Routing And Designing Networks For Two Transportation Problems, Liu Su Apr 2019

Routing And Designing Networks For Two Transportation Problems, Liu Su

USF Tampa Graduate Theses and Dissertations

Routing and designing are essential for transportation networks. With effective routing and designing policies, transportation networks can work safely and efficiently. There are two transportation problems: hazardous materials (hazmat) transportation and warehouse logistics. This dissertation addresses the routing of networks for both problems. For hazmat transportation, the routing can be regulated via network design. Due to catastrophic consequences of potential accidents in hazmat transportation, a risk-averse approach for routing is necessary. In this dissertation, we consider spectral risk measures, for risk-averse hazmat routing. In addition, we introduce a network design problem to select a set of closed road segments for …


Diversity And Network Coded 5g Wireless Network Infrastructure For Ultra-Reliable Communications, Nabeel Ibrahim Sulieman Feb 2019

Diversity And Network Coded 5g Wireless Network Infrastructure For Ultra-Reliable Communications, Nabeel Ibrahim Sulieman

USF Tampa Graduate Theses and Dissertations

This dissertation is directed towards improving the performance of 5G Wireless Fronthaul Networks and Wireless Sensor Networks, as measured by reliability, fault recovery time, energy consumption, efficiency, and security of transmissions, beyond what is achievable with conventional error control technology. To achieve these ambitious goals, the research is focused on novel applications of networking techniques, such as Diversity Coding, where a feedforward network design uses forward error control across spatially diverse paths to enable reliable wireless networking with minimal delay, in a wide variety of application scenarios. These applications include Cloud-Radio Access Networks (C-RANs), which is an emerging 5G wireless …


Pursuing Resilience Of Coastal Communities Through Sustainable And Integrated Urban Water Management, Pacia Díaz Nov 2018

Pursuing Resilience Of Coastal Communities Through Sustainable And Integrated Urban Water Management, Pacia Díaz

USF Tampa Graduate Theses and Dissertations

Reliability of water supply in the urban setting has become essential for communities to function and thrive. It is needed for more than mere human consumption and well-being. Although modern cities have water treatment and distribution systems, pressures from urbanization, population growth and the anticipated pressures of climate change are affecting the quality of water supply and the reliability of treatment and distribution systems. There is therefore an urgent need to take appropriate measures to improve the resilience of water supply systems before the impacts are irreversible.

Improving the resilience of water supply systems can be a challenge. In the …


A Cost Benefit Analysis Of Using A Battery Energy Storage System (Bess) Represented By A Unit Commitment Model, Nemanja Mihailovic Nov 2018

A Cost Benefit Analysis Of Using A Battery Energy Storage System (Bess) Represented By A Unit Commitment Model, Nemanja Mihailovic

USF Tampa Graduate Theses and Dissertations

This thesis aims to provide a general overview of a cost and benefit analysis of incorporating a battery energy storage system within unit commitment model.

The deregulation of the electricity market in the U.S. has only been around for the last two decades. With renewable energy and energy storage systems becoming less expensive, a decentralized market scheme is becoming more popular and plausible. The scope of this work is to provide a fundamental understanding of unit commitment and a cost analysis of applying a battery energy storage system to an already established power system.

A battery energy storage system (BESS) …


Connected Autonomous Vehicles: Capacity Analysis, Trajectory Optimization, And Speed Harmonization, Amir Ghiasi Jul 2018

Connected Autonomous Vehicles: Capacity Analysis, Trajectory Optimization, And Speed Harmonization, Amir Ghiasi

USF Tampa Graduate Theses and Dissertations

Emerging connected and autonomous vehicle technologies (CAV) provide an opportunity to improve highway capacity and reduce adverse impacts of stop-and-go traffic. To realize the potential benefits of CAV technologies, this study provides insightful methodological and managerial tools in microscopic and macroscopic traffic scales. In the macroscopic scale, this dissertation proposes an analytical method to formulate highway capacity for a mixed traffic environment where a portion of vehicles are CAVs and the remaining are human-driven vehicles (HVs). The proposed analytical mixed traffic highway capacity model is based on a Markov chain representation of spatial distribution of heterogeneous and stochastic headways. This …


Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca Mar 2018

Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca

USF Tampa Graduate Theses and Dissertations

Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice …


Understanding The Linkages Between Urban Transportation Design And Population Exposure To Traffic-Related Air Pollution: Application Of An Integrated Transportation And Air Pollution Modeling Framework To Tampa, Fl, Sashikanth Gurram Nov 2017

Understanding The Linkages Between Urban Transportation Design And Population Exposure To Traffic-Related Air Pollution: Application Of An Integrated Transportation And Air Pollution Modeling Framework To Tampa, Fl, Sashikanth Gurram

USF Tampa Graduate Theses and Dissertations

Rapid and unplanned urbanization has ushered in a variety of public health challenges, including exposure to traffic pollution and greater dependence on automobiles. Moreover, vulnerable population groups often bear the brunt of negative outcomes and are subject to disproportionate exposure and health effects. This makes it imperative for urban transportation engineers, land use planners, and public health professionals to work synergistically to understand both the relationship between urban design and population exposure to traffic pollution, and its social distribution. Researchers have started to pay close attention to this connection, mainly by conducting observational studies on the relationship between transportation, urban …


Improving Service Level Of Free-Floating Bike Sharing Systems, Aritra Pal Nov 2017

Improving Service Level Of Free-Floating Bike Sharing Systems, Aritra Pal

USF Tampa Graduate Theses and Dissertations

Bike Sharing is a sustainable mode of urban mobility, not only for regular commuters but also for casual users and tourists. Free-floating bike sharing (FFBS) is an innovative bike sharing model, which saves on start-up cost, prevents bike theft, and offers significant opportunities for smart management by tracking bikes in real-time with built-in GPS. Efficient management of a FFBS requires: 1) analyzing its mobility patterns and spatio-temporal imbalance of supply and demand of bikes, 2) developing strategies to mitigate such imbalances, and 3) understanding the causes of a bike getting damaged and developing strategies to minimize them. All of these …


Water, Sanitation, And Citizenship: Perceptions Of Water Scarcity, Reuse, And Sustainability In Valparaiso De Goias, Brazil, Paola Andrea Gonzalez Nov 2017

Water, Sanitation, And Citizenship: Perceptions Of Water Scarcity, Reuse, And Sustainability In Valparaiso De Goias, Brazil, Paola Andrea Gonzalez

USF Tampa Graduate Theses and Dissertations

Access to reliable water and sanitation are two important goals to improve livelihoods around the world. Providing access to improved and safe water resources that are equitable and appropriate to local needs is important to improve sustainability long-term. In addition, framing access to water and sanitation as basic human rights is often used as a rationale in developing new water, sanitation, and hygiene interventions in developing countries around the world. But not all countries consider access to safe water and sanitation as a human right. In the thesis, the politics of improving and investment in water access and sanitation provision …


How Transportation Network Companies Could Replace Public Transportation In The United States, Matthew L. Kessler Nov 2017

How Transportation Network Companies Could Replace Public Transportation In The United States, Matthew L. Kessler

USF Tampa Graduate Theses and Dissertations

The quantity of cell phone applications or mobile apps have seen an upsurge at an exponential rate in under a decade. Many have been created for a variety of industries, including transportation. The advent and subsequent commercialized implementation of near-instant transport by a middleman-type of app is now known as a Transportation Network Company or TNC. Examples of the more renowned TNCs are Uber, Lyft and Sidecar.

In recent years, TNCs have cultivated a tremendous following, to the degree of taxicab desertion. Moreover, the massive success of TNCs led to expansion of its capacities into public transportation.

The TNC’s expeditious …


Autonomous Vehicles: An Empirical Assessment Of Consumers’ Perceptions, Intended Adoption, And Impacts On Household Vehicle Ownership, Nikhil Menon Jul 2017

Autonomous Vehicles: An Empirical Assessment Of Consumers’ Perceptions, Intended Adoption, And Impacts On Household Vehicle Ownership, Nikhil Menon

USF Tampa Graduate Theses and Dissertations

Emerging automotive and transportation technologies have provided revolutionary possibilities in the way we might travel in the future. Major car manufacturers and technology giants have demonstrated significant progress in advancing and testing autonomous vehicles in real-life traffic conditions. Governmental agencies are grappling with how to plan transportation systems for a world with autonomous vehicles. Past research has shown that not all technologies are immediately welcomed by the public. Autonomous Vehicles would have to likely go through a similar phase, and would need to overcome not just technological challenges but also social barriers for successful penetration into the marketplace. Most previous …