The Unified Modeling Language (UML) has quickly become the industry standard for object-oriented software development. It is being widely used in organizations and institutions around the world. However, UML is often found to be too complex for novice systems analysts. Although prior research has identified difficulties novice analysts encounter in learning UML, no viable solution has been proposed to address these difficulties. Sequence-diagram modeling, in particular, has largely been overlooked. The sequence diagram models the behavioral aspects of an object-oriented software system in terms of interactions among its building blocks, i.e. objects and classes. It is one of the most commonly-used UML diagrams in practice. However, there has been little research on sequence-diagram modeling. The current literature scarcely provides effective guidelines for developing a sequence diagram. Such guidelines will be greatly beneficial to novice analysts who, unlike experienced systems analysts, do not possess relevant prior experience to easily learn how to develop a sequence diagram. There is the need for an effective sequence-diagram modeling technique for novices. This dissertation reports a research study that identified novice difficulties in modeling a sequence diagram and proposed a technique called CHOP (CHunking, Ordering, Patterning), which was designed to reduce the cognitive load by addressing the cognitive complexity of sequence-diagram modeling. The CHOP technique was evaluated in a controlled experiment against a technique recommended in a well-known textbook, which was found to be representative of approaches provided in many textbooks as well as practitioner literatures. The results indicated that novice analysts were able to perform better using the CHOP technique. This outcome seems have been enabled by pattern-based heuristics provided by the technique. Meanwhile, novice analysts rated the CHOP technique more useful although not significantly easier to use than the control technique. The study established that the CHOP technique is an effective sequence-diagram modeling technique for novice analysts.

A "Geometrodynamical Analog to Electric Charge" (or "p-charge") is defined (as in the earlier paper by Unruh, [Gen. Rel. and Grav., 2, (1971), pp 27-33 ] to be the period on a p-cycle (p = 1, 2, or 3) of a p-form which is constructed out of only the Riemann tensor or its derivatives. A previously-unpublished proof by Unruh is briefly summarized which proves that no non-zero p-charges can exist on a completely unrestricted metric field. The metric field is then constrained to obey Einstein's equations for empty space, and sets of linearly-independent, purely-gravitational p-forms are analyzed to determine if p-charges can be defined under these conditions. A scheme is developed, based on the spin-tensor representation of the gravitational field, to generate complete sets of such p-forms, arid calculate their derivatives, with a symbolic-manipulation computer program. It is shown that no gravitational p-forms that are linear combinations of less than five Riemann tensors and less than nine derivatives will result in p-charges. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Origination of the uniform agricultural cooperatives ("UAC") and their legal basis Abstract: The aim of this thesis was to map in detail the process of the formation of unified agricultural cooperatives. Furthermore, I have tried to characterize the basic features that played a role in the process of the formation of unitary agricultural cooperatives. In my thesis, I proceed chronologically from the publication of the Kosice Government Programme to the government's declaration of 15 September 1953. The first part of my work is devoted to the post-war period. In the introduction of the first part I try to outline the situation that prevailed in the then Czechoslovakia and I accentuate any mention of cooperatives. I then turn to the so-called six agricultural acts and the Hradec programme. The second part of my work is devoted to the events from the victory in February until the adoption of the law on unified agricultural cooperatives. This section begins by mentioning the first post-February government program statement and the agricultural laws passed on March 21, 1948. Next, I present the first post-war agricultural cooperatives concept. Much space is then devoted to the Information Bureau Resolution of June 28, 1948, and the subsequent creation of the conditions for the unified agricultural cooperatives...

With the exception of metropolitan school systems, it has been only during recent years that districts have felt the need for written board policies. '!'his need was generated by the stimulus of increased population growth and mobility especially since World War II, With growing numbers of children entering school, districts were forced to grow and change to meet the new demands made on them, No longer was it possible to conduct school affairs with the informality characterized by the "little rod schoolhouse". Increased size and the concomitant problems inherent in delegation of authority and implementation of pollcy throughout the school system encouraged school districts to organize their operations more efficiently. 'l'his necessitated the codification and systematization of the policies by which the district functions. As districts grew and the operation or school plants became more complex, school boards and administrators began to realize that school policies must be in writing to avoid administrator-board misunderstandings and community dissension.

Many school systems throughout the United States have presented and tried various all-year-round school plans. The ever changing social and economic conditions of educational problems. Occasionally a practical solution of these has been to alter the conventional nine month school program to an all-year school plan. This has not always proven advantageous because boards of education many times failed to ascertain parental reaction before implementing the new educational program.

Die Anwendbarkeit des Master Curve-(MC-)Konzepts zur Charakterisierung des Zähigkeitszustandes bestrahlter Reaktordruck¬behälter-(RDB-)Stähle wurde an drei RDB-Stählen überprüft: IAEA-Referenzstahl 3JRQ57, 1JFL11 (vergleichbar mit 22NiMoCr3-7) sowie russischer WWER-440 Grundwerkstoff KAB-B. In Zugversuchen, Charpy-V-Tests, Risswiderstandskurven nach ASTM E1820 und Master Curve Tests zur Bestimmung der Referenztemperatur T0 nach ASTM E1921 wurden der unbestrahlte Ausgangszustand, je drei Bestrahlungszustände bis hin zu Neutronenfluenzen von 100∙10^18 n/cm² (E>1MeV) sowie bei 475°C/100h thermisch ausgeheilte Zustände untersucht. Mit zusätzlichen auf dem MC-Konzept basierenden Auswerteverfahren nach SINTAP, multimodalem MC-Ansatz (MML) sowie der Unified Curve erfolgte die Bewertung des Einflusses von Materialinhomogenitäten und möglicher MC-Formänderung bei hohen Fluenzen. Wie erwartet geht Neutronenbestrahlung mit Verfestigung und Duktilitätsabnahme einher, d.h. Härte, Festigkeitskennwerte, Charpy-V-Übergangstemperaturen T28J und T41J sowie T0 steigen mit der Neutronenfluenz, während die Bruchdehnung und Hochlagenzähigkeit abnehmen. Am bestrahlungsempfindlichsten reagiert der Stahl 3JRQ57, gefolgt von KAB-B und 1JFL11. Durch die Ausheilbehandlung von 475°C/100h erholen sich die Werkstoffkennwerte der Zugversuche, Charpy-V-Tests und MC-Versuche auf den jeweiligen unbestrahlten Ausgangszustand. Die technischen Ersatzkennwerte für duktile Rissinitiierung bleiben relativ unbeeinflusst von der Neutronenbestrahlung. Die MC nach ASTM E1921 beschreibt die Bruchzähigkeits-Temperaturverläufe für alle drei RDB-Stähle in allen Bestrahlungs- und Ausheilzuständen gut. Bei den niedrig und mittel bestrahlten Zuständen liegen meist mehr als 5% der KJc(1T)-Werte unterhalb der MC-Kurve für 5% Versagenswahrscheinlichkeit. Die MC beschreibt den hoch bestrahlte Zustand (ca. 100∙10^18 n/cm², E>1MeV) aller drei RDB-Stähle sehr gut, auch für Daten außerhalb des Gültigkeitsbereiches T0±50K, und auch für den bestrahlungsempfindlichen 3JRQ57 mit inhomogenem Gefüge. Die Unified Curve überbewertet den Einfluss der Neutronenbestrahlung auf die MC-Kurvenform. Eine mögliche Formänderung der MC durch Neutronenbestrahlung konnte bei keinem der drei untersuchten RDB-Stähle nachgewiesen werden.

This thesis describes the design and implementation of a traffic generator that can simulate the traffic of tens of thousands of networking devices from a given traffic model. It is designed to handle traffic models created with Unified Traffic Modelling. The traffic generator is then evaluated and different solutions are compared in an effort to find the best solution for each issue. This thesis is meant to serve as a guideline for future development of traffic generators by providing insight into the problems faced during the development of one.

Charge transport, charging, and subsequent electrostatic discharge due to interactions with the space environment are primary concerns of spacecraft designers. Developing a physical understanding of the interactions of charge with the multitude of materials that spacecraft are composed of is a critical step in understanding and mitigating both short-term and long-term spacecraft degradation. In particular, the study of charge transport in highly insulating materials is critical as they store charge longer, with higher capacity, and with greater destructive capability than other materials.The Utah State University Materials Physics Group, with the funding of the NASA James Webb Space Telescope project and Rocky Mountain Space Consortium, have developed a complete and consistent theoretical model that predicts short-term and long-term storage capabilities based on physical material parameters. This model is applicable across a wide range of experimental systems designed to test specific behaviors that characterize charging phenomena.Modeling and understanding the complex relationships between the spacecraft and its surroundings are fundamentally based on detailed knowledge of how individual materials store and transport charge. The ability to better understand these effects will help make exploring the edges of the universe more stable, reliable, and economic.

The main goal of this research is to evaluate the behavior of earth pressure profiles in unsaturated soils under transient flow. In the first part, an empirical correlation is proposed to obtain the fitting parameters of Brooks and Corey’s soil-water retention model from Fredlund and Xing’s model. The retention models and the proposed equivalency between the models were assessed for 601 soil samples from the unsaturated soils hydraulic database (UNSODA). In the second part, a coupled one-dimensional hydro-mechanical model is introduced and is implemented into Rankine’s earth-pressure model to represent active and passive earth pressure profiles in unsaturated soils under transient flow. A realistic coupling process of infiltration and deformation in the porous medium is established based on the variation in permeability along with deformation in the soil body. The results showed that ignoring the hydro-mechanical coupling effect can lead to underestimation of earth pressure values, especially for fine-grained soils.

Maintaining large-scale legacy applications has been a major challenge for software producers. As the application evolves and gets more complicated, it becomes harder to understand, debug, or modify the code. Moreover, as new members are joining the development team, and others are leaving, the need for a well-documented code arises. Good documentation necessitates the visualization of the code in an easy to understand manner. The Unified Modeling Language (UML), an Object Management Group's (OMG) standard, is a graphical modeling language used for specifying, visualizing, constructing, and documenting software intensive artifacts. UML, which has been accepted as an industry standard in November 1997, has aided the design and maintenance of object-oriented legacy applications. While the software developers were building UML models for their existing applications as part of a reverse-engineering process, development of next generation software applications started from the models (forward-engineering process). In the forward engineering process, the system's code is specified and constructed from the UML models, which evolve as the system evolves in order to maintain consistent documentation and visualization of the system. Moreover, UML has the power of hiding unnecessary details of the system by the ability to model its different views. This enables visualizing the system at different levels of hierarchy. This thesis documents how to use UML to model a software-intensive simulation for the combat systems of a fully automated naval "digital ship". This process started with building the use case diagrams based on the system requirements given by the domain experts. Then activity diagrams were used to describe the exact performance of the use cases. The logical view of the system was built using class, interaction, and activity diagrams. Then, the physical view of the system was built using component diagrams. Finally, an example of the code generation process from the UML models was carried out for one of the system components. These models are to be maintained as the application evolves. Using UML has aided in building a well-structured object-oriented application, validating the use cases of the application with the domain experts, visualizing and validating the structure of the source code before writing it, communicating between different members of the development team, and providing an easily understandable documentation of the system. / Master of Science