• Aggregation in temporal databases

      Kline, Rodger Nickels; Kline, Rodger Nickels (The University of Arizona.The University of Arizona., 19991999)
      Temporal database systems extend relational database systems to support time-varying information. One important such extension is support for time-varying aggregate functions, such as a time-varying average. Our research will show that temporal aggregates may be specified in a semantically well defined manner yet be efficiently implemented as simple extensions to relational databases. We introduce a taxonomy of temporal aggregation, based on a study of all major temporal query languages containing aggregates. The taxonomy categorizes the expressiveness and functionality of temporal aggregation. Based on this taxonomy, we introduce extensions to TSQL2 for temporal aggregation. The proposed language constructs allow one to express the variety of features identified in the taxonomy. We briefly discuss the semantics for the temporal aggregate language extension. We introduce an operator for evaluating temporal aggregates in a temporal relational algebra; the operator was designed to implement the tuple semantics. We show that theoretically, the most efficient evaluation of a temporal aggregate over a relation with n unique timestamps requires Θ(n log n) time, with O(n log n) space in any decision tree algorithm. We provide an example algorithm meeting these requirements, utilizing a 2-3 tree. Based on the requirements for evaluation of the algebraic operator, we introduce a series of main memory algorithms for evaluating temporal aggregates, including the aggregation tree, k-ordered aggregation tree, the chalkboard algorithm, the linked-list algorithm, and show how to perform aggregation using a 2-3 tree. The algorithms exhibit different applicability depending on aspects of the input relation, including sort order, percentage of long-lived tuples, and number of tuples. We also provide an algorithm which executes using only a user-limited amount of memory, the paging aggregation tree. We characterize the effectiveness of these algorithms based on an empirical study of their performance.
    • Antifungal Compounds Produced in Antagonistic Competition Between Marine Fungi

      Tariq, Muhammad Buchan (The University of Arizona., 2012)
      Competition among fungi has been characteristic of antibiotic relationships between microbes, leading to the discovery of novel antimicrobial compounds. This study observed such antagonistic relationships between marine fungi isolated from coral off the coast of Woods Hole, Massachusetts. Competition assays were conducted on these fungal isolates against two chosen competing species on PDA plates. Three fungal isolates were observed to release antifungal compounds inhibiting the growth of the competing species. Methanol extracts were taken from each of the three fungal isolates and ¹H and ¹³C NMR spectra obtained. The three fungi were shown to produce antifungal compounds, not observed in previous studies. 14 fractions were obtained from subjecting the methanol extracts from each of the three fungi to chromatography. The final step remains to test these fractions for antifungal activity leading to the isolation and identification of the antifungal compounds.
    • Converting Sweet Sorghum to Ethanol - An Alternative Feedstock for Renewable Fuels

      Waters, Heather (The University of Arizona., 2012)
      The goal of this project was to design an ethanol production process from sweet sorghum for use as a renewable fuel. Sorghum stalks are first harvested and sent through a series of 2 three-roller extractors (70% total efficiency). Extracted juice is pumped to the reactor for preservation and fermentation. Sodium metabisulfite preserves the juice. Ethanol Red (Saccharomyces cerevisiae) is the fermentation yeast. Following fermentation, the juice (8% ethanol by mass) is distilled to achieve 90% ethanol. A molecular sieve extracts excess water, resulting in 100% ethanol. Plant wastes accumulate during the process. These wastes are collected, dried, and sold as animal feed for profit. The project economics indicate that the overall process is not currently economically feasible. The net present value (NPV) for the optimum economic situation, assuming a 15 year plant lifetime and 15% interest rate, is -$125 M. Under these circumstances, the ethanol would need to be sold at $44.37 per gallon to break even. To improve this process, further development of methods for increasing juice extraction efficiency should be explored. Additionally, the distillation process could be enhanced with a second distillation column to achieve 95% ethanol prior to using the molecular sieve.
    • Facilitating interoperability among heterogeneous geographic database systems: A theoretical framework, a prototype system, and evaluation

      Park, Jinsoo (The University of Arizona., 1999)
      The objective of this research is to develop a formal semantic model, theoretical framework and methodology to facilitate interoperability among distributed and heterogeneous geographic database systems (GDSs). The primary research question is how to identify and resolve various data- and schematic-level conflicts among such information sources. Set theory is used to formalize the semantic model, which supports explicit modeling of the complex nature of geographic data objects. The semantic model is used as a canonical model for conceptual schema design and integration. The intension (including structure, integrity rules and meta-properties) of the database schema is captured in the semantic model. A comprehensive framework classifying various semantic conflicts is proposed. This framework is then used as a basis for automating the detection and resolution of semantic conflicts among heterogeneous databases. A methodology for conflict detection and resolution is proposed to develop interoperable system environment. The methodology is based on the concept of a "mediator." Several types of semantic mediators are defined and developed to achieve interoperability. An ontology is developed to capture various semantic conflicts. The metadata and ontology are stored in a common repository and manipulated by description logic-based operators. A query processing technique is developed to provide uniform and integrated access to the multiple heterogeneous databases. Logic is employed to formalize our methodology, which provides a unified view of the underlying representational and reasoning formalism for the semantic mediation process. A usable prototype system is implemented to provide proof of the concept underlying this work. The system has been integrated with the Internet and can be accessed through any Java-enabled web browser. Finally, the usefulness of our methodology and the system is evaluated using three different cases that represent different application domains. Various heterogeneous geospatial datasets and non-geographic datasets are used during the evaluation phase. The results of the evaluation suggest that correct identification and construction of both schema and ontology-schema mapping knowledge play very important roles in achieving interoperability at the both data and schema levels. The research adopts a multi-methodological approach that incorporates set theory, logic, prototyping, and case study.
    • Identifying Potential Candidate SNP's and Genes Linked to Handedness for Future Study

      Takyar, Ankit (The University of Arizona., 2012)
      The goal was to identify genes for future study that might be linked to handedness for potential candidate gene study. We were able to find 3 major genes through statistically analyzing SNP data within a Genome-wide association Statistical Analysis tool, PLINK. 27 SNPs were chosen based on P-values of below .001, further analysis was done to these 27 SNPs to figure out their gene locus. Using NCBI we found 21 SNPs were within a gene locus. A total of 16 genes were found from the 21 SNPs that were located within a gene locus. Three extra genes were examined since they were located in a gene of interest CTNNA2. The genes found were further screened for high expression in subcortical regions and that have been implicated in neural function or brain development. Out of the 17 genes determined, IRAK2, NRG1, and CTNNA2 adhered to the criteria for screening.
    • In-home solid fuel use and cardiovascular disease: a cross-sectional analysis of the Shanghai Putuo study

      Lee, Mi-Sun; Hang, Jing-qing; Zhang, Feng-ying; Dai, He-lian; Su, Li; Christiani, David C (2013-09-23)
    • Indexing and path query processing for XML data

      Li, Quanzhong (The University of Arizona., 2004)
      XML has emerged as a new standard for information representation and exchange on the Internet. To efficiently process XML data, we propose the extended preorder numbering scheme, which determines the ancestor-descendant relationship between nodes in the hierarchy of XML data in constant time, and adapts to the dynamics of XML data by allocating extra space. Based on this numbering scheme, we propose sort-merge based algorithms, εA-Join and εε-Join, to process ancestor-descendant path expressions. The experimental results showed an order of magnitude performance improvement over conventional methods. We further propose the partition-based algorithms, which can be chosen by a query optimizer according to the characteristics of the input data. For complex path expressions with branches, we propose the Containment B⁺-tree (CB-tree) index and the IndexTwig algorithm. The CB-tree, which is an extension of the B⁺-tree, supports both the containment query and the reverse containment query. It is an effective indexing scheme for XML documents with or without a small number of recursions. The proposed IndexTwig algorithm works with any index supporting containment and reverse containment queries, such as the CB-tree. We also introduce a simplified output model, which outputs only the necessary result of a path expression. The output model enables the Fast Existence Test (FET) optimization to skip unnecessary data and avoid generating unwanted results. Also in this dissertation, we introduce techniques to process the predicates in XML path expressions using the EVR-tree. The EVR-tree combines the advantages of indexing on values or elements individually using B+-trees. It utilizes the high value selectivity and/or high structural selectivity, and provides ordered element access by using a priority queue. At the end of the dissertation, we introduce the XISS/R system, which is an implementation of the XML Indexing and Storage System (XISS) on top of a relational database. The XISS/R includes a web-based user interface and a XPath query engine to translate XPath queries into efficient SQL statements.
    • Integrating Biophilic Principles and Therapeutic Design Elements in Outdoor Spaces for Children at Tucson Medical Center

      Davidson, Deryn (The University of Arizona., 2013)
      As concern for the health and wellbeing of children grows in a society geared toward a more sedentary lifestyle, many doctors and therapists are pointing to the importance of access to, and time spent interacting with the natural world. The idea of using the restorative properties of nature in healing has been around since ancient times. There is currently a renaissance in the health care industry looking at the importance of incorporating gardens into the design of health care facilities once again. This project proposes to explore the importance for children in health care facilities to have access to the natural world while using the biophilia hypothesis as a framework for design. Furthermore, the benefits of outdoor areas for the families (particularly siblings) of child patients and the staff of the health care facilities was explored. Through the use of literature and case reviews, data was collected and synthesized to determine the elements best used to strengthen the designs for children’s therapeutic environments. Outcomes include three models of therapeutic environments including focus areas for the Tucson Medical Center campus in Tucson, Arizona.
    • Islamic Finance for Poverty Alleviation

      Chuk, T S (The University of Arizona., 2012)
      There is a direct relation between religion and economics. Islamic Finance links the pillars of Islamic faith with financial instruments to produce an ethics based approach to finance. The increasing occurrence of Islamic Financial Institutions worldwide lays the groundwork for Islamic Finance to become a viable ethics based alternative to conventional finance. This thesis outlines the modern origins of Islamic Finance, its distinguishing characteristics and approaches to poverty alleviation in the Middle East and North Africa using the instruments of Islamic Finance to conclude that development approaches under the scope of Islamic Finance are viable.
    • Micro-Specialization: Dynamic Code Specialization in DBMSes

      Zhang, Rui (The University of Arizona., 2012)
      Database management systems (DBMSes) form a cornerstone of modern IT infrastructure, and it is essential that they have excellent performance. In this research, we exploit the opportunities of applying dynamic code specialization to DBMSes, particularly by focusing on runtime invariant present in DBMSes during query evaluation. Query evaluation involves extensive references to the relational schema, predicate values, and join types, which are all invariant during query evaluation, and thus are subject to dynamic value-based code specialization. We observe that DBMSes are general in the sense that they must contend with arbitrary schemas, queries, and modifications; this generality is implemented using runtime metadata lookups and tests that ensure that control is channelled to the appropriate code in all cases. Unfortunately, these lookups and tests are carried out even when information is available that renders some of these operations superfluous, leading to unnecessary runtime overheads. We introduce micro-specialization, an approach that uses relation- and query-specific information to specialize the DBMS code at runtime and thereby eliminate some of these overheads. We develop a taxonomy of approaches and specialization times and propose a general architecture that isolates most of the creation and execution of the specialized code sequences in a separate DBMS-independent module. We show that this approach requires minimal changes to a DBMS and can improve the performance simultaneously across a wide range of queries, modifications, and bulk-loading, in terms of storage, CPU usage, and I/O time of the TPC-H and TPC-C benchmarks. We also discuss an integrated development environment that helps DBMS developers apply micro-specializations to identified target code sequences.
    • Natural Heart: Yangchun Lake Suburban Center Master Plan

      Wang, Yuxin (The University of Arizona., 2013)
      Urbanization in China is rapidly improving with the economic growth. But the development that ignores environment has caused lots of environmental problems in Chinese cities, especially the large ones. As the capital of Hubei Province, Wuhan is the fifth among China cities for its size and its economic production. Because of extreme urbanization and high dense population in Wuhan city, some significant issues have been constantly emerged: lack of adequate wastewater management and water resources protection, urgent need for efficient solution to sludge treatment and disposal, serious urban flooding because of the natural flow or urban lakes and streams restriction, degradation of water quality, and so on. These issues have been seriously impacted the quality life in the city. Along with the urbanization, the conflicts between urban development and ecosystem are inescapable. How can urban development balance environmental sensitivity to support ecological health in the vulnerable urban ecosystem and mitigate the problems in the city? This project tries to redesign a master plan for Yangchun Lake sub-urban center in Wuhan city and find suitable ways to mitigate these problems with attention to the environmental, functional, economic, social and aesthetics aspects of the proposed solutions. The design will balance the urban development and environmental protection, support and enhance the development of a new ecological urban center.
    • New Life Behind Bars - A Prison Retrofit From Prison to Community Resource

      Machado, Micaela (The University of Arizona., 2013)
      Sustainability practices in design development are a common goal in urban settings, especially in an environment such as the arid Southwest U.S. where resources are limited. Here, sunshine and heat are abundant where water resources are low. So, how can we use these circumstances and constraints to our advantage in future designs or in potential retrofits? Institutional establishments with long-term residents, such as prisons, which use a significant amount of resources can reduce their energy, food and water costs by using sustainable practices. These practices can help reduce the costs of prisoner housing and eventually lower costs to tax payers. This project focuses on a hypothetical retrofit of the Wilmot Department of Corrections (Wilmot D.O.C.) prison facility in Tucson, AZ.
    • Revitalization of Alleys - creating safe, social and green networks in central Tucson

      Zhao, Kexin (The University of Arizona., 2013)
      Alleys are underutilized corridors that can potentially provide many valuable uses in cities. Alleys can be used for multiple purposes during the day and night: conventional functions, dog walking, water harvesting, art display and as renewable energy showcases, to name a few. In addition, they can become welcoming and popular linear gathering spaces. On a grander scale, they can be used as networks and connections between destinations. This project proposes to evaluate the current challenges and opportunities of alleys in central Tucson, to create multiple design templates for safe, social, and green alleys, and to enhance the connectivity to Tucson Modern Streetcar Areas.
    • Supporting the Procedural Component of Query Languages over Time-Varying Data

      Gao, Dengfeng (The University of Arizona., 2009)
      As everything in the real world changes over time, the ability to model thistemporal dimension of the real world is essential to many computerapplications. Almost every database application involves the management oftemporal data. This applies not only to relational data but also to any datathat models the real world including XML data. Expressing queries ontime-varying (relational or XML) data by using standard query language (SQLor XQuery) is more difficult than writing queries on nontemporal data.In this dissertation, we present minimal valid-time extensions to XQueryand SQL/PSM, focusing on the procedural aspect of the two query languagesand efficient evaluation of sequenced queries.For XQuery, we add valid time support to it by minimally extendingthe syntax and semantics of XQuery. We adopt a stratum approach which maps a&tauXQuery query to a conventional XQuery. The first part of the dissertationfocuses on how to performthis mapping, in particular, on mapping sequenced queries, which are byfar the most challenging. The critical issue of supporting sequenced queries(in any query language) is time-slicing the input data while retaining periodtimestamping. Timestamps are distributed throughout anXML document, rather than uniformly in tuples, complicating the temporalslicing while also providing opportunities for optimization. We propose fiveoptimizations of our initial maximally-fragmented time-slicing approach:selected node slicing, copy-based per-expression slicing, in-placeper-expression slicing, and idiomatic slicing, each of which reducesthe number of constant periods over which the query is evaluated.We also extend a conventional XML query benchmark to effect a temporal XMLquery benchmark. Experiments on this benchmark show that in-place slicingis the best. We then apply the approaches used in &tauXQuery to temporal SQL/PSM.The stratum architecture and most of the time-slicing techniques work fortemporal SQL/PSM. Empirical comparison is performed by running a variety of temporalqueries.
    • Theory and Design Considerations of a Saline Ecological Landscape: A constructive method to reduce brine waste volume

      Bresdin, Cylphine (The University of Arizona., 2013)
      Pertinent abiotic and biotic factors and their interdependencies necessary to comprehend the ecology of saline systems are investigated and evaluated. A designed saline ecosystem is proposed as a constructive method to reduce waste volume. Landscape pattern is investigated as the vehicle for an evapotranspiration induced directional saline gradient. A demonstration site is used to explore conceptual design application of the idea of ecosystem pattern consisting of a linear sequence of ecotopes, each displaying its own ecological community in relation to salinity range and site context. Biota is relinquished to self-organization. Potential for research use of the ecosystem is illustrated.