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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.
1

Behavior, association patterns and habitat use of a small community of bottlenose dolphins in San Luis Pass, Texas

Henderson, Erin Elizabeth 01 November 2005 (has links)
Photoidentification surveys of bottlenose dolphins (Tursiops truncatus) were conducted from December of 2002 through December of 2003 in Chocolate Bay, Texas, and the adjacent Gulf of Mexico area. The research represented the continuation of an ongoing study of the dolphins of this area. Behavioral sampling was carried out on a small resident community of dolphins that seasonally reside in Chocolate Bay, as well as on dolphins found along the gulf coastline. Resident dolphins had a daily behavioral pattern, with peaks of foraging activity in the morning, traveling at midday, and socializing in late afternoon. Gulf dolphins had small mean group sizes of 3.4 and were primarily observed foraging and traveling, with little socializing. When resident and gulf dolphins interacted, the mean group size increased to 12 and the proportion of social behavior increased. Association indices demonstrated no long-lasting associations among adult male dolphins, while strong associations existed between several females. Females revealed two patterns of association; they were either members of a female band with other mother-calf pairs, or were solitary with no strong affiliations with any dolphins other than their calf. Males seemed to disperse upon maturation, which maintained the community size of approximately 35 animals. Behavioral evidence indicates the resident community is matrilinealy related and composed largely of adult females and their offspring. A few adult males remain resident, while most young males disperse from the community and may rove among the gulf population. Although mating probably occurs between resident and gulf dolphins, sources of both maternity and paternity for residents need to be determined, and further behavioral work needs to be carried out to support this hypothesis.
2

Behavior, association patterns and habitat use of a small community of bottlenose dolphins in San Luis Pass, Texas

Henderson, Erin Elizabeth 01 November 2005 (has links)
Photoidentification surveys of bottlenose dolphins (Tursiops truncatus) were conducted from December of 2002 through December of 2003 in Chocolate Bay, Texas, and the adjacent Gulf of Mexico area. The research represented the continuation of an ongoing study of the dolphins of this area. Behavioral sampling was carried out on a small resident community of dolphins that seasonally reside in Chocolate Bay, as well as on dolphins found along the gulf coastline. Resident dolphins had a daily behavioral pattern, with peaks of foraging activity in the morning, traveling at midday, and socializing in late afternoon. Gulf dolphins had small mean group sizes of 3.4 and were primarily observed foraging and traveling, with little socializing. When resident and gulf dolphins interacted, the mean group size increased to 12 and the proportion of social behavior increased. Association indices demonstrated no long-lasting associations among adult male dolphins, while strong associations existed between several females. Females revealed two patterns of association; they were either members of a female band with other mother-calf pairs, or were solitary with no strong affiliations with any dolphins other than their calf. Males seemed to disperse upon maturation, which maintained the community size of approximately 35 animals. Behavioral evidence indicates the resident community is matrilinealy related and composed largely of adult females and their offspring. A few adult males remain resident, while most young males disperse from the community and may rove among the gulf population. Although mating probably occurs between resident and gulf dolphins, sources of both maternity and paternity for residents need to be determined, and further behavioral work needs to be carried out to support this hypothesis.
3

Pattern formation and evolution on plants

Sun, Zhiying January 2009 (has links)
Phyllotaxis, namely the arrangement of phylla (leaves, florets, etc.) has intrigued natural scientists for over four hundred years. Statistics show that about 90\% of the spiral patterns has their numbers of spirals belonging to two consecutive members of the regular Fibonacci sequence. (Fibonacci(-like) sequences refer to any sequences constructed with the addition rule $a_{j+2}=a_{j}+a_{j+1}$, while the regular Fibonacci sequence refers to the particular sequences 1,1,2,3,5,8,13,...) Historical research on pattern formation on plants, tracing back to as early as four hundred years ago, was mostly geometry based. Current studies focus on the activities on the cellular level and study initiation of primordia (the initial undifferentiated form of phylla) as a morphogenesis process cued by some signal. The nature of the signal and the mechanisms governing the distribution of the signal are still under investigation. The two top candidates are the biochemical hormone auxin distribution and the mechanical stresses in the plant surface (tunica). We built a model which takes into consideration the interactions between these mechanisms. In addition, this dissertation explores both analytically and numerically the conditions for the Fibonacci-like patterns to continuously evolve (i.e. as the mean radius of the generative annulus changes over time, the numbers of spirals in the pattern increase or decreases along the same Fibonacci-like sequence), as well as for different types of pattern transitions to occur. The essential condition for the Fibonacci patterns to continuously evolve is that the patterns are formed annulus by annulus on a circular domain and the pattern-forming mechanism is dominated by a quadratic nonlinearity. The predominance of the regular Fibonacci pattern is determined by the pattern transitions at early stages of meristem growth. Furthermore, Fibonacci patterns have self-similar structures across different radii, and there exists a one-to-one mapping between any two Fibonacci-like patterns. The possibility of unifying the previous theory of optimal packing on phyllotaxis and the solutions of current mechanistic partial differential equations is discussed.
4

Cemetery Siting in the Bluestone Reservation Area, Summers County, West Virginia: 1750-1997

Cottle, Rebecca K. 25 August 1997 (has links)
This thesis examines the effects of transportation network changes, settlement pattern changes, population density and terrain characteristics upon cemetery siting. Due to the practically inviolate legal status of cemeteries, they provide a window to the past. Geographic Information Systems technology was used to analyze geophysical attributes of the cemetery sites. As transportation modes changed and improved, the distances from decedent's residences to burial sites increased. Also, cemetery upkeep is somewhat related to ease of accessibility, but other factors enter into this relationship. Personal interviews suggest that family"ties to the land" have an effect upon cemetery utilization and maintenance in rural southern West Virginia. Early cemeteries were sited in river and creek bottoms. More recently sited cemeteries are located at higher elevations. / Master of Science
5

Variation in the structure, composition, and dynamics of a foundation tree species at multiple scales and gradients

Bhuta, Arvind Aniel Rombawa 25 January 2012 (has links)
Scientists and land managers often focus on the Southeastern Plains and Coastal Plain of the southeastern United States when considering the ecology, restoration, and management of longleaf pine (Pinus palustris P. Mill.) communities and ecosystems. However, the range of this foundation tree species and its associated communities and ecosystems also extend into the Piedmont and Montane Uplands: the Piedmont of Alabama, Georgia, North and South Carolina and Virginia; the Ridge and Valley of Alabama and Georgia; and the Southwestern Appalachians of Alabama. The composition, structure, and dynamics of Piedmont and Montane Uplands longleaf pine communities have been understudied compared to their Southeastern Plains and Coastal Plain counterparts, and knowledge is based on historical accounts and a handful of studies at site-specific scales. The biogeography and ecology of Piedmont and Montane Uplands longleaf pine communities differ significantly from those in the Southeastern Plains and Coastal Plain. My research combines geospatial and ecological approaches to provide insights on current composition, structure, and dynamics of longleaf pine communities in the Southeastern Plains, Piedmont, and Ridge and Valley at multiple scales and highlights differences and similarities with communities in the Coastal Plain. The Piedmont and Montane Uplands longleaf pine communities showed high variation in canopy tree diversity compared to those in the Coastal Plain. Longleaf pine was sometimes the only canopy tree, while in other communities longleaf pine was one constituent in a mixed oak-pine canopy. My study showed that longleaf pine communities were not just restricted to south-facing slopes as previously thought, but were found on northwestern-facing slopes as well. Analysis of tree rings across my study sites showed that as longleaf pine approaches its northern range margin in the Piedmont and Montane Uplands, its radial growth is restricted by minimum temperature especially at longleaf pine's elevational, latitudinal, and longitudinal extremes; at all sties radial growth was influenced by drought and precipitation. At the local scale, I found that an Alabama Piedmont longleaf pine community showed a diameter-class distribution typical of an old-growth site but contrary to current knowledge, diameter was not a good indicator of age. / Ph. D.
6

An Exploration of the Relationship between Street Patterns and Floodplains in The Woodlands, Texas

Xu, Junping 14 January 2010 (has links)
The objective of this thesis is to explore the relationship between street patterns and floodplains. Although some researchers have written about the relationship between land use and floodplains in The Woodlands, few have discussed how the city form was designed around the hydrological system. This thesis will focus on one aspect of the city form, the street pattern, to determine the effectiveness of street designs' response to floodplains. Unlike the grid-like pattern advocated by the New Urbanists, street patterns in The Woodlands are loops and cul-de-sacs -- a typical suburban pattern at the time it was developed; however, street patterns adapt to the boundaries of floodplains and protect them very well. Using a GIS tool to overlay 100-year floodplains on the street layer, it is clear to see that there are low percentages of streets in the 100-year floodplains. Thus, The Woodlands employed nonstructural techniques to mitigate flood hazard, which minimize the development in floodplains. Flood control in The Woodlands is much better than other places in the Houston area. From flood control and the protection of the natural environment standpoints, the nonstructural techniques are advocated more than structural techniques for floodplains in the development management. Therefore, the design of street patterns in an area is determined by both the aim of convenient transportation and the aim of hazard mitigation.
7

Investigation of a management process: An exploratory study to identify underlying patterns in planning

Dickie, Carolyn January 2007 (has links)
This study linked the management activity of planning with Alexander et al.’s (1977) concept of pattern languages developed within architecture. Since the 1990s the concept has been expanded in the information systems discipline to document software development practices. Moreover, uses of the patterning concept have focussed on software from a technical aspect; however, authors such as Coplien and Harrison (2004) have moved beyond the purely technical aspects and have used the concept of patterns to discuss issues of organisational structure. Similarly, within the discipline of management, process management tools are used to manage, track or simplify core processes by recognising patterns that can be replicated to produce more effective and efficient structural systems. Whether practitioners seek continuous improvement through control of business structures, inputs or processes, planning of desired outcomes is critical. Practical implementation difficulties continue despite a plethora of independent planning tools/applications available to managers. Consequently, a focus of this study was to explore human processes of planning in organisations, using Manns et al.’s (2001) definition of patterns to determine whether identifiable underlying patterns existed. There is a dearth of literature and practical resources related to the concept of management patterns. However, identifying flexible patterns in planning would provide a direct link between the theory of management planning, its practical implementation or both. / Qualitative research was conducted by means of within case and cross-case analysis of interviews of senior planning personnel in public and private organisations. At a general (macro) level, planning performances in all participating organisations indicated a strong relationship to Alexander’s concept of patterns; i.e. an underlying pattern that represented actual planning practices has been identified. Participating public sector organisations demonstrated some common themes in their planning, usually due to government accountability demands. In participating private sector each organisation undertook very different processes, largely because there was no internal or external accountability. The major conclusion in this study was that the reported practice of planning in participating organisations exhibited underlying patterns that matched Alexander-type patterns at the general (macro) level. Other original outcomes generated in this study included identifying, at the specific (micro) level, evidence of common indicators and categories of planning, development of individual case maps displaying pattern indicators, design of a planning component model using information that emerged from the interview data and within case analysis, amendment to that model after cross-case analysis and linking of the findings to the literature. Overall, the findings led to a revision of the conceptual model devised from available literature on planning and the concept of patterns.
8

Application of design patterns in framework development

Della, Lewis, n/a January 1999 (has links)
Since the coining of the term "Design Patterns" in the software engineering context, and specifically as related to object-oriented applications, there has been an increasing emphasis placed on the relevance of patterns in successfully designing object-oriented software, by the provision of generic, recurring designs. Various authors have produced design pattern catalogues as a record of applied design pattern experiences [Buschmann+96] [Gamma+95] [Coad92]. These catalogues are invaluable to experienced practitioners. However, the examples are frequently given in the context of a complex application with partially coded examples. Also, there is no standard with regard to the name used to designate a particular design pattern and, in some cases, different designers have designated relatively similar patterns with quite different names. This limits their accessibility to less experienced designers who require fully coded examples applied in a familiar landscape. Thus, while patterns have dramatically shaped the manner in which object-oriented solutions are developed, the full realisation of their use and reuse potential by inexperienced practitioners is limited by lack of completely coded examples. In this thesis we consider the implementation (in Java), using fully coded examples, of a number of design patterns applied to business oriented applications. These will be applied in an application specific environment, with the resultant framework being capable of use across a family of similar applications. The source code examples are compact enough so that the pattern structure can be readily appreciated, while at the same time being large enough to demonstrate the pattern in a practical, viable sense. These are applied in a familiar application domain, business-oriented applications, resulting in an application framework, that is, a partially completed system that provide the core architecture functionality, suitable for reuse across a family of systems. In this way, the link between design patterns and their implementation via these coded frameworks will be easier to comprehend. It is anticipated that the end result will be a better appreciation of design patterns and a clearer understanding of how to apply these patterns, with the availability of a set of useful, reusable software components, with appropriate interface connection, to be used as central building blocks, in developing object-oriented solutions for business applications.
9

Software engineering with analysis patterns

Geyer-Schulz, Andreas, Hahsler, Michael January 2001 (has links) (PDF)
The purpose of this article is twofold, first to promote the use of patterns in the analysis phase of the software life-cycle by proposing an outline template for analysis patterns that strongly supports the whole analysis process from the requirements analysis to the analysis model and further on to its transformation into a flexible design. Second we present, as an example, a family of analysis patterns that deal with a series of pressing problems in cooperative work, collaborative information filtering and sharing, and knowledge management. We present the step-by-step evolution of the analysis pattern virtual library with active agents starting with a simple pinboard. In this paper we propose that using patterns in the analysis phase has the potential to reducing development time by introducing reuse already at the analysis stage and by improving the interface between analysis and design phase. To quantify our proposal we present results from the Virtual University project of the Vienna University of Economics and Business Administration, where the analysis patterns developed in this paper were used to implement several information systems. (author's abstract) / Series: Working Papers on Information Systems, Information Business and Operations
10

Seasonal rainfall regime in the Central Elburz, Iran

Mohammadi-Sheshnarmi, Hossein Morad January 1998 (has links)
The area chosen for this study is the Central Elburz of Iran surrounding the southern end of the Caspian Sea. It includes an important rainfall dependent agricultural area and merges into the semi arid zone with a well defined boundary. From social and agricultural points of view rainfall is by far the most important climatic factor in many tropical and subtropical countries. An important aspect in the development of agriculture in the Central Elburz is the determination of the seasonal rainfall patterns. This thesis should be considered as a contribution to the study of the seasonal rainfall regime of Iran, with direct value to agriculture in the region. The purpose of this thesis is to examine the pattern of rainfall especially in relation to the growing season both in time and spatially. Also the thesis describes the variation in the availability of moisture for growth throughout this region. The thesis examines annual, monthly and seasonal rainfall over the region. Multivariate analysis has demonstrated that the study area can be divided into three rainfall regions. Before considering any analysis which could allow prediction on probability of future rainfall amounts, it is important to consider whether or not there on trends or fluctuations. The result of this analysis is that, few stations show positive trends, others negative trends. Rainfall variability has been quantified by the coefficient of variation index and analysed in a similar way to that of rainfall distribution. The results for most stations shown a relationship between variability indices and rainfall amounts. In relation to the study of variability, an assessment of rainfall probability and reliability has been considered with reference to rainfall critical for crops. Probability has a particular value in its application to agriculture. In this study 90% probability is examined and this is related to the economy of the agriculture units in the Central Elburz. Also 80 and 75 percent probability are presented. These spatial patterns of probability thus provide maps of agricultural potential. Rainfall records are analysed to provide estimates, percentage points of rainfall totals, variation in the start, and end of the rainy season and or the probability of dry spells within the rainy season. The estimation of potential evapotranspiration which are discussed and explained in this study are based on the Blaney- Criddle and Pan evaporation methods. The water balance approach provides the most rational method of analysing seasonal pattern since it considers characteristics of the dominant crops in this area, wheat and citrus, and it examines effectiveness of rainfall for these crops. Blaney- Criddle and Pan evaporation have been used to estimate potential evaporation for wheat and citrus and compared to actual evapotranspiration to give potential water deficit. The adoption of probability analysis of potential water deficit provides a valuable description of water availability for crops in this region of variable rainfall.

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