Ontologies are formal knowledge models that describe concepts and relationships and enable data integration, information search, and reasoning. Ontology Design Patterns (ODPs) are reusable solutions intended to simplify ontology development and support the use of semantic technologies by ontology engineers. ODPs document and package good modelling practices for reuse, ideally enabling inexperienced ontologists to construct high-quality ontologies. Although ODPs are already used for development, there are still remaining challenges that have not been addressed in the literature. These research gaps include a lack of knowledge about (1) which ODP features are important for ontology engineering, (2) less experienced developers' preferences and barriers for employing ODP tooling, and (3) the suitability of the eXtreme Design (XD) ODP usage methodology in non-academic contexts. This dissertation aims to close these gaps by combining quantitative and qualitative methods, primarily based on five ontology engineering projects involving inexperienced ontologists. A series of ontology engineering workshops and surveys provided data about developer preferences regarding ODP features, ODP usage methodology, and ODP tooling needs. Other data sources are ontologies and ODPs published on the web, which have been studied in detail. To evaluate tooling improvements, experimental approaches provide data from comparison of new tools and techniques against established alternatives. The analysis of the gathered data resulted in a set of measurable quality indicators that cover aspects of ODP documentation, formal representation or axiomatisation, and usage by ontologists. These indicators highlight quality trade-offs: for instance, between ODP Learnability and Reusability, or between Functional Suitability and Performance Efficiency. Furthermore, the results demonstrate a need for ODP tools that support three novel property specialisation strategies, and highlight the preference of inexperienced developers for template-based ODP instantiation---neither of which are supported in prior tooling. The studies also resulted in improvements to ODP search engines based on ODP-specific attributes. Finally, the analysis shows that XD should include guidance for the developer roles and responsibilities in ontology engineering projects, suggestions on how to reuse existing ontology resources, and approaches for adapting XD to project-specific contexts.

This diploma thesis deals with the company performance assessment of the selected organization. The described organization is called ENVINET Inc. and it is analyzed according to multi-criteria model START PLUS. According to this model, the final point assessment of the company is realised, strengths and weaknesses and areas for improvement are identified. There are also proposed specific measures whose implementation can improve the performance of the analyzed company.

The use of semantic technologies and Semantic Web ontologies in particular have enabled many recent developments in information integration, search engines, and reasoning over formalised knowledge. Ontology Design Patterns have been proposed to be useful in simplifying the development of Semantic Web ontologies by codifying and reusing modelling best practices. This thesis investigates the quality of Ontology Design Patterns. The main contribution of the thesis is a theoretically grounded and partially empirically evaluated quality model for such patterns including a set of quality characteristics, indicators, measurement methods and recommendations. The quality model is based on established theory on information system quality, conceptual model quality, and ontology evaluation. It has been tested in a case study setting and in two experiments. The main findings of this thesis are that the quality of Ontology Design Patterns can be identified, formalised and measured, and furthermore, that these qualities interact in such a way that ontology engineers using patterns need to make tradeoffs regarding which qualities they wish to prioritise. The developed model may aid them in making these choices. This work has been supported by Jönköing University.

Sediment has profound effects on water quality. Correspondingly, water quality modeling often needs sediment transport modeling. However, simplified descriptive sediment transport was originally employed for water quality modeling, and the linkage between sediment transport models and water quality models is less developed. Therefore, the main purposes of this study were to develop general methods of coupling sediment transport and water quality models and to improve sediment transport modeling for water quality modeling. Linkage of sediment transport and water quality was discussed and a comprehensive sediment transport literature review was conducted. SEDDEER (Sediment Deposition and Erosion), a stand-alone sediment and contaminant fate and transport model, which simulates one water box and the underlying multiple sediment bed layers, was developed. SEDDEER for Visual Basic for Application (SEDDEER_VBA) was written in VBA. SEDDEER for FORTRAN (SEDDEER_FOR) is the corresponding FORTRAN model. To improve WASP in terms of sediment transport, SEDDEER_FOR was incorporated into the WASP TOXI7 module as the starting point to generate the coupled WASP model (WASP_SEDDEER). Verification and validation of SEDDEER_VBA were conducted prior to model application and incorporation. A comprehensive model test was performed to show that SEDDEER_FOR is computationally identical to SEDDEER_VBA. Simple tests were carried out to verify the fluxes across the sediment-water interface and ensure that the coupling of the WASP water column and SEDDEER bed models is correct. The testing results indicated that these models were verified and/or validated. SEDDEER was used to evaluate the effects of sediment on contaminant transport. WASP_SEDDEER, WASP7.4, and EFDC were applied to Mobile Bay to demonstrate the capabilities of WASP_SEDDEER, and WASP_SEDDEER produced a reasonable and consistent modeling result. The results of the study indicated that SEDDEER can be used for one-box sediment and contaminant fate and transport modeling, and also incorporated into water quality models. In addition, WASP_SEDDEER coupling was implemented correctly and can be applied to the real world. Finally, study results show that sediment affects contaminant fate and transport mostly by external forcing and flow conditions, and contaminant fate and transport varies with different sediment and contaminant characteristics and sediment transport processes.

Assessment of water quality within the Escatawpa River system was accomplished utilizing the Better Assessment Science Integrating Point and Nonpoint Sources (BASINS 2.0) to develop the watershed model, and the CE-QUAL-W2 software to develop the estuary model. The watershed model was utilized to quantify both hydrodynamic and water quality (fecal coliforms) characteristics of the watershed for a simulation period spanning from 1990 through 1999. Herein, calibration and application results are presented for watershed and estuary simulations made in an uncoupled manner. The models were developed such that loose coupling of watershed and estuary models can be accomplished as a subsequent phase of this ongoing project. CE-QUAL-W2 model calibration was performed utilizing a set of site specific data acquired on the Escatawpa Estuary System during an intensive survey period of September 10-15, 1997. Dissolved oxygen levels in the system were closely examined, with regards to the impacts from point source discharges.

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This research addresses the Reference Watershed Approach (RWA) in the TMDL process for benthic impairments. In the RWA, do different land use sources (DOQQ and NLCD) or use of alternative water quality models (GWLF and SWAT) result in different stressor loadings? Is there a difference in stressor loadings when different reference watersheds are used? Study results showed that using different land use sources resulted in required stressor reductions that were different by greater than 10%. In one scenario, use of the NLCD-based land use parameters results in 3.5 times greater reductions than use of DOQQ-based land use parameters. With respect to water quality model selection, in two of the three scenarios considered, a difference in stressor reduction requirements of greater than 10% resulted from using different models. Differences in load reduction requirements are also seen when different reference watersheds are used, regardless of the water quality model or the land use source used. Different references result in a difference of as much as 73% in required sediment reductions in the impaired watershed: the required reductions using one reference watershed are 6.2 times as great as when another is used. Possible alternatives to the RWA include water quality standards to set the target level for many of the common stressors on the benthic assemblage, regression equations that relate benthic stressors to the RBP II score, or averaging of stressor reduction requirements obtained from using the Reference Watershed Approach on several different reference watersheds. / Master of Science

The Lake Manassas Watershed is a 189 km2 basin located in the Northern Virginia suburbs of Washington, DC. Lake Manassas is a major waterbody in the watershed and serves as a drinking water source for the City of Manassas. Lake Manassas is experiencing eutrophication due to nutrient loads associated with agricultural activities and urban development in its drainage areas. Two watershed model applications using HSPF, and one receiving water quality model application using CE-QUAL-W2, were linked to simulate Lake Manassas as well as its drainage areas: the Upper Broad Run (126.21 km2) and Middle Broad Run (62.79 km2) subbasins. The calibration of the linked model was for the years 2002-05, with a validation period of 2006-07. The aspects of effective modeling of nutrient losses and nutrient management practices in the Lake Manassas watershed were investigated. The study was mainly conducted in the Upper Broad Run subbasin, which was simulated with an HSPF model. For nutrient simulation, HSPF provides two algorithms: PQUAL (simple, empirically based) and AGCHEM (detailed, process-based). This study evaluated and compared the modeling capabilities and performance of PQUAL and AGCHEM, and investigated significant inputs and parameters for their application. Integral to the study was to develop, calibrate and validate HSPF/PQUAL and HSPF/AGCHEM models in the Upper Broad Run subbasin. "One-variable-at-a-time" sensitivity analysis was conducted on the calibrated Upper Broad Run HSPF/PQUAL and HSPF/AGCHEM models to identify significant inputs and parameters for nutrient load generation. The sensitivity analysis results confirmed the importance of accurate meteorological inputs and flow simulation for effective nutrient modeling. OP (orthophosphate phosphorus) and NH4-N (ammonium nitrogen) loads were sensitive to PQUAL parameters describing pollutant buildup and washoff at land surface. The significant PQUAL parameter for Ox-N (oxidized nitrogen) load was groundwater nitrate concentration. For the HSPF/AGCHEM model, fertilizer application rate and time were very important for nutrient load generation. NH4-N and OP loads were sensitive to the AGCHEM parameters describing pollutant adsorption and desorption in the soil. On the other hand, plant uptake of nitrogen played an important role for Ox-N load generation. A side by side comparison was conducted on the Upper Broad Run HSPF/PQUAL and HSPF/AGCHEM models. Both PQUAL and AGCHEM provided good-to-reasonable nutrient simulation. The comparison results showed that AGCHEM performed better than PQUAL for OP simulation, but PQUAL captured temporal variations in the NH4-N and Ox-N loads better than AGCHEM. Compared to PQUAL, AGCHEM is less user-friendly, requires a lot more model input parameters and takes much more time in model development and calibration. On the other hand, use of AGCHEM affords more model capabilities, such as tracking nutrient balances and evaluating alternative nutrient management practices. This study also demonstrated the application of HSPF/AGCHEM within a linked watershed-reservoir model system in the Lake Manassas watershed. By using the outputs generated by the HSPF/AGCHEM models in the Upper Broad Run and Middle Broad Run subbasins, the Lake Manassas CE-QUAL-W2 model adequately captured water budget, temporal and spatial distribution of water quality constituents associated with summer stratification in the lake. The linked model was used to evaluate water quality benefits of implementing nutrient management plan in the watershed. The results confirmed that without the nutrient management plan OP loads would be much higher, which would lead to OP enrichment and enhanced algae growth in Lake Manassas. / Ph. D.

Dentre as tecnologias de desenvolvimento de software que promovem o reuso com o objetivo de construir sistemas com prazos e custos menores, sem sacrificar a qualidade dos produtos, está o Desenvolvimento Baseado em Componentes (DBC). O Desenvolvimento Baseado em Componentes consiste na construção de sistemas pela composição de componentes de software de acordo com um processo de desenvolvimento específico. Para garantir a qualidade desses sistemas, é importante garantir a qualidade de seus componentes. A falta da garantia da qualidade dos componentes de software destinados à reutilização é um dos fatores de inibição do DBC, e existe certa carência de pesquisas sobre a qualidade de componentes de software. Desta maneira, o principal objetivo deste trabalho foi a definição de um modelo de qualidade específico para componentes de software, fornecendo a base para a especificação de requisitos de qualidade e para a avaliação de qualidade dos mesmos. O Modelo está embasado nas normas ISO/IEC 9126 e ISO/IEC 12119, e também na literatura especializada. Uma ferramenta para apoiar avaliações de componentes (e de produtos de software de forma geral) também foi desenvolvida. Foram realizadas ainda quatro avaliações de componentes através de estudos de casos para verificar a aplicabilidade e utilidade do modelo de qualidade e da ferramenta desenvolvida. Dois questionários foram respondidos pelos avaliadores responsáveis pelas avaliações coletando assim, suas considerações sobre o modelo de qualidade e sobre a ferramenta / Among the software development technologies that promote the reuse aiming to build systems with periods and smaller costs, without sacrificing the quality of products, is the Component-Based Development (CBD). The Component-Based Development consists on the construction of systems by the composition of software components according to a specific development process. To guarantee the quality of those systems, it is important to guarantee the quality of their components. The lack of warranty of the quality of the software components destined to reuse is one of the inhibition factors of CBD, and there is certain lack of researches about quality of software components. This way, the main objective of this work was the formalization of a specific quality model for software components, supplying the base for the specification of quality requirements and for the quality evaluation of the same ones. The model is based on the norms ISO/IEC 9126 and ISO/IEC 12119, and also in the specialized literature. A tool to support components evaluations (and software products in a general way) was also developed. It was realized four components evaluations through case studies to verify the applicability and usefulness of the quality model and the developed tool. Two questionnaires were answered by the appraisers responsible for the evaluations collecting thereby, their considerations on the quality model and the tool