The South African (SA) export fruit industry is vital to the SA economy, contributing about 20% (or 4 million tons) to agricultural production. As a one billion US dollar export industry in 2002, the country exports about 42% of its fresh fruit production (Shepherd 2003:2), contributing 75% of all farm income for fruit (Kriel 2002:4). The industry is well positioned with regard to its southern hemisphere competitors (Argentina, Australia, Chile and New Zealand) in terms of average growth in export volumes. However, the market requirements are constantly changing and competition is fierce due to the general oversupply of fruit in major markets. The limitations of the regulated environment eventually led to deregulation in August 1997 and to the phasing out of the statutory bodies. The new deregulated market structure radically changed the competitive profile of the industry by lifting the artificial barriers that existed for fruit exports. However, there was still a major barrier to performance – having the knowledge and ability to deal with export processes (S. Rigotti, personal communication, 13 June 2003 – Manager Information Systems, Capespan, P.O. Box 505, Bellville, South Africa, 7535). Exporters experienced a combination of problems. Few had proper systems, which meant that access to critical information was severely hampered. It was, for instance, difficult to record and verify the cost, quite often resulting in serious losses. Producer payments were inaccurate and late most of the time; sometimes payments only occurred during the harvesting of the next season. Data integrity on the supply chain was suspect, because of fragmented information channels and duplicated capturing at various points in the chain. The internal challenges were compounded by a difficult time in the markets. Strong competition, globalization and the effects of world-wide overproduction, caused prices to drop dramatically. Consequently many farmers and exporters incurred enormous debts and went bankrupt (Van der Ham, Becker and Guis 2002a; 2002b). In 2000, the third year after deregulation, the fruit export industry as a whole lost an estimated one billion rand in export earnings and declared itself in crisis (Mather 2003). SA's international image slipped because of all the negative consequences of deregulation (Symington 2003:5).

No description available.

Automated testing is superior to manual testing because it is both faster to execute and achieves greater test coverage. Typical test generators are implemented in a programming language of the tester’s choice. Because most programming languages have complex syntax and semantics, the test generators are often difficult to develop and maintain. Context-free grammars are much simpler: they can describe complex test inputs in just a few lines of code. Therefore, Grammar-Based Test Generation (GBTG) has received considerable attention over the years. However, questions about certain aspects of GBTG still remain, preventing its wider application. This thesis addresses these questions using YouGen NG, an experimental framework that incorporates some of the most useful extra-grammatical features found in the GBTG literature. In particular, the thesis describes the mechanisms for (1) eliminating the combinations of less importance generated by a grammar, (2) creating a grammar that generates combinations of correct and error values, (3) generating GUI playback scripts through GBTG, (4) visualizing the language generation process in a complex grammar, and (5) applying GBTG to testing an Really Simple Syndication (RSS) feed parser and a web application called Code Activator (CA). / Graduate

Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1991. / Vita. Abstract. Includes bibliographical references (leaves 91-97). Also available via the Internet.

Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (p. 151-162).

Manufacturing industries rely on automated manufacturing systems to improve the efficiency, quality and flexibility of production. Such systems typically consist of a variety of manufacturing machinery and control hardware, e.g. CNC machine tools, robots, PCs, Programmable Logic Controllers (PLCs) etc., which operate concurrently. The cost of developing and implementing an automated manufacturing system is high, and is particularly so if the control system is found to be unreliable or unsafe during operation. Distributed Control Systems are generally used to control complex concurrent systems,At present the methods used to develop DCSs tend to follow a sequence of steps, viz. a statement of the requirements of the DCS, a functional specification of the DCS, the design of the DCS, generation of the software code for the DCS, implementation of the software. This step approach is inadequate because of the dissimilarity of techniques used to represent each step, which leads to difficulties in ensuring equivalence between the final implementation of the DCS and the initial requirements, which in turn leads to errors in the final software. To overcome this, work has been conducted to unify the specification, design, and software coding phases of the DCS development procedure by ensuring formal equivalencies between them. One particular outcome of such previous work is a tool named Petri Net - Occam Methodology, developed by Dr. P. Gray, which produces dependable Occam code for DCSs. Gray's methodology produces readable designs, directly from the specification of systems, in a graphical but formal way, and results in a Petri Net graph which is equivalent to the final Occam code. However, his methodology is not for a complete DCS but only for one containing Transputers. The PLC is widely used in industry and an integral part of DCSs for Automated Manufacture. This research has developed a methodology, named PNPLC, which produces dependable PLC control programs, in a graphical but formal way, directly from a system's specification. It uses the same tool, Petri Nets, for both designing and simulating the control system, and specifies rules which ensure the correct design, simulation and encoding of PLC programs. The PN designs are a one-to-one equivalent to PLC code and can be directly translated into Ladder Diagrams. Therefore if the simulation shows the design to be correct, the final software will be correct. PNPLC works as a stand alone tool for developing dependable PLC control programs, and also unifies with Gray's methodology to produce a complete tool for developing a resilient DCS containing Transputers and PLCs. The unification of the two methodologies is also reported in this thesis. The research work presented in this thesis contributes to knowledge in the field of DCS development. Recommendations for further work regarding the applicability of the unified methodology on a wide scale industrial basis are also given.

abstract: Automated planning addresses the problem of generating a sequence of actions that enable a set of agents to achieve their goals.This work investigates two important topics from the field of automated planning, namely model-lite planning and multi-agent planning. For model-lite planning, I focus on a prominent model named Annotated PDDL and it's related application of robust planning. For this model, I try to identify a method of leveraging additional domain information (available in the form of successful plan traces). I use this information to refine the set of possible domains to generate more robust plans (as compared to the original planner) for any given problem. This method also provides us a way of overcoming one of the major drawbacks of the original approach, namely the need for a domain writer to explicitly identify the annotations. For the second topic, the central question I ask is ``{\em under what conditions are multiple agents actually needed to solve a given planning problem?}''. To answer this question, the multi-agent planning (MAP) problem is classified into several sub-classes and I identify the conditions in each of these sub-classes that can lead to required cooperation (RC). I also identify certain sub-classes of multi-agent planning problems (named DVC-RC problems), where the problems can be simplified using a single virtual agent. This insight is later used to propose a new planner designed to solve problems from these subclasses. Evaluation of this new planner on all the current multi-agent planning benchmarks reveals that most current multi-agent planning benchmarks only belong to a small subset of possible classes of multi-agent planning problems. / Dissertation/Thesis / Masters Thesis Computer Science 2016

This thesis concerns the development of a robotic cell to perform assembly and handling operations on cloth.- A flexible automation approach was adopted, in which the robot was required to control the cloth panel during both handling and sewing operations, without the aid of hard automation attachments which might limit the flexibility of the system. The cell consisted of an adaptively controlled robot, a hierarchy of controllers, a conventional sewing machine, a two-fingered fabric steering end-effector, and several sensor systems. A technique was developed for producing a seam parallel to an edge of arbitrary contour, in which two cameras, a cloth tension sensor and the sewing machine's shaft encoder provided the sensory input. Two sensory servo control systems were required, one control system generated the robot's trajectory to maintain a small constant cloth tension, and the other directed the robot to manipulate the cloth panel to maintain a constant seam width. The design of the cloth tension control was based on the measured frequency response of the open loop system. The seam width control was designed using simulation studies, which accounted for the control transfer function, and nonlinearities such as camera pixel resolution, time delays and robot motion limitations. Several robotic handling techniques were developed, so that a cloth panel placed arbitrarily on the sewing table could be set up for an edge seaming operation, and the cloth could be rotated about the needle. The system's flexibility was demonstrated in the assembly of an irregularly shaped cloth panel, in which three adjacent sides were sewn up.

The first generation of autonomous vehicles are equipped with Adaptive Cruise Control (ACC), which automatically adjusts the vehicle speed to maintain a safe following distance and gap selected by the driver. Today’s ACC can also operate at low speeds and signalized intersections on arterial streets. However, the latency of the on-board sensors can significantly increase the start-up lost time and reduce capacity and increase delay on arterials with signalized intersections. This study investigates the fundamental characteristics of traffic flow under ACC vehicles and mixed driving scenarios. Field tests demonstrated that the design of ACC vehicles can lead to delayed response and gradual acceleration when operating on arterials with speed fluctuations due to disturbances. This study also examines the effect of increasing adoption of ACC vehicles at signalized intersections. Field validated simulations suggest that 100% market penetration of ACC vehicles could decrease the capacity by up to 10%. Furthermore, fuel consumption and emissions (CO2, NOx, CO, HC) can increase by up to 33%. / Includes bibliography. / Thesis (MS)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection

High-voltage SiC Schottky barrier diodes have been fabricated with 1mm square contacts. The SBD?s were fabricated using both an argon implant and a field plate overlap for edge termination. The Versatile Automated Semiconductor Testing and Characterization system was designed to fully test and characterize these devices with as little human interaction as possible. The focus of this thesis is to discuss the usefulness of the VASTAC system. Emphasis is placed on it?s versatility derived from a modular design allowing the system to perform a variety of tests. Specifically, the testing and characterization of silicon carbide Schottky Barrier Diodes will be discussed in relation to the systems performance, cost, and the time it takes to test a wafer.