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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

A STUDY OF PREHISTORIC BURNED ROCK MIDDENS IN WEST CENTRAL TEXAS

Creel, Darrell Glenn, Creel, Darrell Glenn January 1986 (has links)
Burned rock middens large accumulations of thermally fractured rock are among the most common features in Archaic archaeolgical sites in Central Texas. With a sample of 1654 archaeological sites, the distribution of burned rock midden sites is compared with the occurrence of live oak savanna in an area of approximately 55,800 square kilometers in west central Texas. The objective of this distributional analysis is a preliminary assessment of the hypothesis that burned rock middens relate to prehistoric exploitation of acorns. The similarity of the distribution of burned rock middens to both the modern and postulated Archaic distribution of live oak savanna supports this hypothesis. On this basis, it is Inferred that acorns from Quercus fusiformis and perhaps Q. texana and Q. sinuata, var. breviloba were major foods during at least part of the Archaic period. Burned rock middens are suggested to be accumulations mainly of discarded boiling stone fragments broken from use in stone-boiling of acorn foods. Data on modern areas of live oak savanna are used to show that the acorn production Is quite substantial in some portions of Central Texas and is sufficient in most years to support a population density of 1-3 persons per square kilometer for at least half a year. The implications of this potential are evaluated, especially in regard to the kinds of archaeological remains found at burned rock midden sites. The similarity of the distributions of burned rock middens and live oak savanna suggest that the modern general occurrence of live oak savanna is little changed from that 5000 years ago. The possible loss of oaks in one portion of the study area may reflect either short or long periods of drying conditions at some time since 5000 BP.
332

Performance analysis software for reinforced concrete beam-columns under various load and displacement patterns

Rohleder, Schyler January 1900 (has links)
Master of Science / Department of Civil Engineering / Asad Esmaeily / Performance-based building design is a necessity in geographic locations where buildings are susceptible to large earthquakes and high winds. This design method requires an analysis of the performance of the structural system with loadings and deflections caused by earthquakes and wind. Current design codes include the load intensity in analysis procedures, but do not consider the effect of load pattern in the performance analysis of reinforced concrete columns. Because a thorough analysis must take into consideration load pattern and load intensity, computer software is ideal to analyze these systems. A computer program was originally developed by Esmaeily (USC_RC), and was revised later to be renamed (KSU_RC) in order to make the analysis of concrete column performance accurate, yet simple for design purposes. This analytical tool used analytical methods and material models, verified against experimental data, to accurately predict the performance of reinforced concrete columns under various loading conditions, including any pattern in lateral direction and independently variable axial load. However, the program was limited to circular, rectangular, hollow circular and rectangular sections and uniaxial lateral curvature and displacement. The next generation of the program, KSU RC 2.0, was developed to overcome the aforesaid limitations.
333

Changes in Parent-Child Relationships as a Result of Family Therapy

Kinney, Delane R. 05 1900 (has links)
The problem with which this study is concerned is whether pathogenic parental patterns which precipitate and maintain children's maladjustment can be ameliorated through family therapy. Specifically, this investigation focused on how parental attitudes and sons' perceptions of parental attitudes are altered by therapy.
334

Quantifying Design Principles in Reusable Software Components

Moore, Freeman Leroy 12 1900 (has links)
Software reuse can occur in various places during the software development cycle. Reuse of existing source code is the most commonly practiced form of software reuse. One of the key requirements for software reuse is readability, thus the interest in the use of data abstraction, inheritance, modularity, and aspects of the visible portion of module specifications. This research analyzed the contents of software reuse libraries to answer the basic question of what makes a good reusable software component. The approach taken was to measure and analyze various software metrics as mapped to design characteristics. A related research question investigated the change in the design principles over time. This was measured by comparing sets of Ada reuse libraries categorized into two time periods. It was discovered that recently developed Ada reuse components scored better on readability than earlier developed components. A benefit of this research has been the development of a set of "design for reuse" guidelines. These guidelines address coding practices as well as design principles for an Ada implementation. C++ software reuse libraries were also analyzed to determine if design principles can be applied in a language independent fashion. This research used cyclomatic complexity metrics, software science metrics, and traditional static code metrics to measure design features. This research provides at least three original contributions. First it collects empirical data about existing reuse libraries. Second, it develops a readability measure for software libraries which can aid in comparing libraries. And third, this research developed a set of coding and design guidelines for developers of reusable software. Future research can investigate how design principles for C++ change over time. Another topic for research is the investigation of systems employing reused components to determine which libraries are more successfully used than others.
335

Multivariate Analyses of Amphibian and Reptilian Distribution in Texas

Ward, Rocky 08 1900 (has links)
Presence-absence data for amphibians, chelonians, saurians, ophidians, and the terrestrial and aquatic ecological guilds of reptilians were analyzed using multivariate analyses. Geographically consistant distributional patterns were found for all faunal groupings. The correspondence between analyses of the different taxa and guilds was not perfect, but similarities were found. All analyses agreed on the presence of a distinctive region in east Texas. Most analyses also agreed on the presence of distinctive regions in south Texas, the Trans-Pecos, the Edwards Plateau, and north-west Texas. There is strong correspondence between interpretations of the analyses based on the amphibian, saurian, ophidian, and terrestrial reptilian distributions, and the biotic provinces produced by earlier, subjective analyses. The Edwards Plateau and a region on the western periphery of east Texas were found to be transitional between other, more faunally distinctive areas for most fauna! groups. Detailed examination of these regions suggested they are best described as clinal in nature. The environmental variables which were most effective in explaining patterns in the distribution of the various taxa and guilds were related to precipitation. However, variations in temperature and physiography were also important predictors of distribution for several of the groups. The distributions of soil and vegetation associations were also found to be related to amphibian and reptilian distribution.
336

An Analysis of Respiratory Mechanisms Controlling Exercise Hyperpnea During Cycle Ergometry Conducted at Selected Workloads and Pedal Frequencies

Wise, Charles Hamilton 12 1900 (has links)
Respiratory and metabolic patterns in response to variations in exercise workload (WL) and pedal frequency (RPM) were examined in 10 healthy males. Each subject performed WLs of low (L), moderate (M) and high (H) intensity, equivalent to 25%, 50% and 75% V02 m a x at 7 pedal frequencies (40, 50, 60, 70, 80, 90 and 100 RPM). ANOVA ( 3 X 7 design) indicated that WL and RPM had independent and significant effects on all respiratory and metabolic measures; i.e., the greater the WL and RPM, the higher the HR, V02, VC02, Ve, Fb, Vt, Vt/Ti, Vt/Te and Ti/TtQt and the lower the Ti and Te. However, analysis of the interaction effect revealed different response patterns for Fb, Vt, Ti, Vt/Ti, Vt/Te and Ve among the WLs. During L-WL, increases in RPM produced increases in Ve which were due to progressive increases in both Fb and Vt. However, during M-WL and H-WL, increases in RPM produced increases in Ve which were accomplished by a constant Vt and a progressive increase in Fb. My findings suggest that during low WLs, the signal for Vt is dependent on rate of contraction, while during M-WL and H-WL, the signal for Vt appears to depend on force of contraction and is independent of increasing RPM. When comparing the L-WL and M-WL, alterations in Ve, Fb, Vt/Ti and Vt/Te in relation to increases in pedal frequency were additive. However, when these two lower WLs were compared to the H-WL, the interaction between pedal frequency and Ve, Fb, Vt/Ti and Vt/Te was multiplicative. In addition, the interaction between WL and RPM on Vt and Ti was additive when comparing the M-WL and H-WL and multiplicative when these two lower WLs were compared to the H-WL. Correlation analysis indicated that for all WLs, Te was more highly related to Fb than was Ti, while Vt/Te was more highly related to Ve than was Vt/Ti. Our findings suggest that during M-WL and H-WL, increases in Ve are accomplished by progressive increases in Fb and decreases in Te, while during L-WL, increases in Ve are achieved by progressive increases in both Fb and Vt.
337

The Effects of Extinction on Human Performance Following Exposure to Fixed Ratio Schedules of Reinforcement

Anderson, Richard L. 05 1900 (has links)
This experiment examined the effects of extinction on rate of responding and several topographical and temporal measures in adult humans. Three college students were trained to type the sequence 1•5•3 on a numeric keypad on a computer. The subjects were exposed to different fixed-ratio schedules of reinforcement (FR1, FR 5, and FR10 respectively) and extinction. Subjects displayed typical schedule performances during the maintenance phase of the experiment. During extinction the performances were disrupted, they showed a "break and run" pattern and a general decrease in responding. Also, new topographical and temporal patterns emerged. These data are consistent with those reported for non-human species and special human populations.
338

Privacy issues of the Internet of Things / Privacy issues of the Internet of Things

Mašek, Martin January 2016 (has links)
More and more devices and sensors are around us in today's world. There is an increasing tendency to connect devices and sensors to the Internet. We call such network the Internet of Things. As the cost of computing power continues to decrease, data collection and analysis becomes cheaper. Thus, we are able to get much better insight into different domains. This could be a problem in commercial sector, where we do not want to compromise proprietary know how or data. Especially big concerns are around personal data. We can now analyse behavior of people or get access to personal information such as health or spending patterns. This thesis addresses these privacy issues. Powered by TCPDF (www.tcpdf.org)
339

Data Mining for Induction of Adjacency Grammars and Application to Terrain Pattern Recognition

Leighty, Brian David 01 January 2009 (has links)
The process of syntactic pattern recognition makes the analogy between the syntax of languages and the structure of spatial patterns. The recognition process is achieved by parsing a given pattern to determine if it is syntactically correct with respect to a defined grammar. The generation of pattern grammars can be a cumbersome process when many objects are involved. This has led to the problem of spatial grammar inference. Current approaches have used genetic algorithms and inductive techniques and have demonstrated limitations. Alternative approaches are needed that produce accurate grammars while remaining computationally efficient in light of the NP-hardness of the problem. Co-location rule mining techniques in the field of Knowledge Discovery and Data Mining address the complexity issue using neighborhood restrictions and pruning strategies based on monotonic Measures Of Interest. The goal of this research was to develop and evaluate an inductive method for inferring an adjacency grammar utilizing co-location rule mining techniques to gain efficiency while providing accurate and concise production sets. The method incrementally discovers, without supervision, adjacency patterns in spatial samples, relabels them via a production rule and repeats the procedure with the newly labeled regions. The resulting rules are used to form an adjacency grammar. Grammars were generated and evaluated within the context of a syntactic pattern recognition system that identifies landform patterns in terrain elevation datasets. The proposed method was tested using a k-fold cross-validation methodology. Two variations were also tested using unsupervised and supervised training, both with no rule pruning. Comparison of these variations with the proposed method demonstrated the effectiveness of rule pruning and rule discovery. Results showed that the proposed method of rule inference produced rulesets having recall, precision and accuracy values of 82.6%, 97.7% and 92.8%, respectively, which are similar to those using supervised training. These rulesets were also the smallest, had the lowest average number of rules fired in parsing, and had the shortest average parse time. The use of rule pruning substantially reduced rule inference time (104.4 s vs. 208.9 s). The neighborhood restriction used in adjacency calculations demonstrated linear complexity in the number of regions.
340

Tempo de espera para a ocorrência de palavras em ensaios de Markov / Waiting time for the occurrence of patterns in Markov chains

Florencio, Mariele Parteli 06 April 2016 (has links)
Consideremos uma sequência de lançamentos de moedas em que denotamos o resultado de cada lançamento por H, se der cara, ou por T, se der coroa. Formemos uma palavra apenas com H\'s e T\'s, por exemplo, HHHHH ou HTHTH. Quantas vezes arremessaremos uma mesma moeda ate que uma das duas palavras acima ocorrera? Por exemplo, dadas as sequências THTHHHHH e TTHTTHTHTH. O numero de vezes que arremessamos a moeda ate que HHHHH e HTHTH ocorreram pela primeira vez e oito e dez, respectivamente. Podemos generalizar a ideia acima para um numero finito de palavras em um alfabeto finito qualquer. Assim, o nosso principal objetivo dessa dissertação e encontrarmos a distribuição do tempo de espera ate que um membro de uma coleção finita de palavras seja observado em uma sequência de ensaios de Markov de letras de um alfabeto finito. Mais especificamente, as letras de um alfabeto finito são geradas por uma cadeia de Markov ate que uma das palavras de uma coleção finita ocorra. Além disso encontraremos a probabilidade de que determinada palavra ocorra antes das demais palavras pertencentes a um mesmo conjunto finito. Por ultimo encontraremos a função geradora de probabilidade do tempo de espera. / Consider a sequence of independent coin flips where we denote the result of any landing for H, if coming up head, or T, otherwise. Create patterns with H\'s and T\'s, for example, HHHHH or HTHTH. How many times do we have to land the same coin until one such two patterns happens? For example, let the sequences being THTHHHHH and TTHTTHTHTH. The number of times that we landed the coin until HHHHH and HTHTH happens it was eight and ten times respectively. We can generalize this idea for a finite number of patterns in any finite set. Then, the first of all interest of this dissertation is to find the distribution of the waiting time until a member of a finite colection of patterns is observed in a sequence of Markov chains of letters in from finite set. More specically the letters in a finite set are generated by Markov chain until one of the patterns in any finite set happens. Besides that, we will find the probability of a pattern happen before of all patterns in the same finite set. Finally we will find the generator function of probability of waiting time.

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