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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.
31

The interrelationships between entrepreneurial competencies, absorptive capacity and innovation capacity

Taljaard, Amorie January 2020 (has links)
Speed and measure of the fourth industrial revolution (Industry 4.0) is bringing about shifts in power, wealth and knowledge. For entrepreneurs, who are known to drive innovation, Industry 4.0 offers a wide scope of opportunities in the future. As a middle-income country, South Africa needs to use its knowledge and innovations to sharpen its innovative edge in order to compete globally and stimulate innovation. Hence, this research attempts to determine the relationships between entrepreneurial competencies, entrepreneurial absorptive capacity and innovation capacity. Three conceptual frameworks of the interrelationships between these constructs were synthesised from the literature. As ample research on entrepreneurial competencies is widely available, a Delphi study was employed, together with a concept matrix to determine which entrepreneurial competencies should be included specifically significant for innovation within the 4IR context in South Africa. Four entrepreneurial competency categories emerged: cognitive (knowledge), functional (skills), social (attitudes and behaviours) and meta (facilitating learning) categories. Using a survey method, the analysis on a sample of 452 innovative entrepreneurs in South Africa was mainly done by empirically testing the causal linear relationship through structural equation modelling (SEM). Furthermore, an Artificial Neural Networking (ANN) technique which tests non-linear relationships and develop pattern recognition as well as modelling was conducted to compare the results of a non-linear relationship with those of a linear relationship. However, explorative comparisons of the performance of linear SEM models with non-linear NN indicated that the SEM models in this case performed better in explaining the variance in the dependent variables than did the ANN. Through the theories of innovative performance, person-entrepreneurial fit and knowledge spillover, the findings of the study indicate the importance of incorporating a unified entrepreneurial competency typology perspective on innovation. The cognitive, functional, social and meta competencies as well as entrepreneurial absorptive capacity are significant predictors of innovation capacity. The implications of this extend to transmitting knowledge through absorptive capacity, which allows entrepreneurs to identify and exploit opportunities, identified from new knowledge sources and incorporated into new innovations. Additionally, entrepreneurial absorptive capacity mediates the relationship between social, meta, and functional competencies and innovation capacity. Entrepreneurial absorptive capacity was also found to be a moderator between cognitive competencies and innovation capacity. Therefore, the development of certain entrepreneurial competencies, significant for innovation, is crucial for improving the strength of the relationship between entrepreneurial absorptive capacity and innovation capacity of entrepreneurs. These results have important implications for Industry 4.0 entrepreneurs, educators, policy makers as well as entrepreneurship models. / Thesis (PhD (Entrepreneurship))--University of Pretoria, 2020. / Business Management / PhD / Unrestricted
32

Leveraging choice modeling technique for enhancing the cyber resilience of the smart grid

Dadi, Kesava Karishma Devi 10 December 2021 (has links) (PDF)
This research focuses on the cyber-attack of the smart grid and its retrieval to a normal state by estimating the smart grid's resilience. This study developed a theoretical model to estimate the resilience of the smart grid using choice modeling. A utility function is formulated based on various factors and sub-factors of resilience to estimate the resilience of the smart grid. Choice modeling is applied to estimate the model parameters in various fields such as marketing, energy, transportation, and health and to predict the outcome.
33

What do we do now? The Role of Absorptive Capacity and Consulting Service Firms in the Internalization of New Knowledge Within Organizations

Nair, Sudhir 01 September 2011 (has links)
The impact of knowledge on firm performance has been seen as one explanation of firm performance heterogeneity, which is a central question in the area of Strategic Management. However, there has been surprisingly limited research into the role of new knowledge internalization within firms. Further, the ubiquitous role of external knowledge providers, especially those that explicitly exist to provide knowledge to firms (Consulting Service Firms) has been negligibly studied. Specifically this dissertation looked at how firms first understand new knowledge and suggested that firms differ in their ability to discern the impact of this new knowledge based on the absorptive capacity that they already possess. I examine how firms internalize this new knowledge and suggest that they can either use existing internal resources or seek external assistance to achieve this internalization. This dissertation has empirically examined these linkages. A survey sent to the top management of 2015 Indian firms, yielded 277 usable responses, which have provided insights into the new knowledge internalization pathways in firms. I use structural equation modeling and hierarchical regressions to test my hypotheses. I find that firms do differ in their use of internal and external knowledge providers, while attempting to internalize new knowledge and that the quality of the relationship impacts the outcomes of any external engagement. I also find that firms with absorptive capacity benefit both by having better short term financial performance and also by being well situated to increase their stocks of knowledge assets, which can help long term performance. This dissertation contributes to several streams of literature in the field of strategic management. I add to the knowledge based view literature and more specifically to the absorptive capacity literature by partially opening the black box of organizational routines. This dissertation also contributes to the professional service literature by suggesting that consultants can help firms generate performance, although this is particularly beneficial to firms that already posses high absorptive capacity. Implications of the results from both practice and research perspectives are discussed and areas of future research are suggested.
34

THE ROLE OF STRATEGIC AND OPERATIONAL ABSORPTIVE CAPACITY IN ORGANIZATIONAL AMBIDEXTERITY

Diaz-Molina, Ivan January 2019 (has links)
In today’s dynamic corporate environment where firms struggle to maintain a competitive advantage, ambidextrous firms focusing on both exploration and exploitation are more likely to survive and prosper in the long run. Scholars have identified and examined a number of antecedents of organizational ambidexterity, but extant studies have not fully explored the role of a firm’s absorptive capacity in developing its organizational ambidexterity. The relevance of the absorptive capacity concept is paramount since new sources of competitive advantage would very likely come from outside the organizations. In this research, I explore the relationship between a firm’s absorptive capacity and organizational ambidexterity by focusing on two levels of absorptive capacity and three dimensions of organizational ambidexterity. Using a survey of 5,600 companies performed by the Government of Chile in 2015, and then a subsample of panel data that includes 760 companies for the 2009-2014 period, I find that both strategic and operational absorptive capacity contribute to the incremental exploitation dimension of organizational ambidexterity. My study contributes to our understanding of the absorptive capacity construct and illuminates how it affects organizational ambidexterity. The study also provides managerial implications as to what kind of external knowledge to procure and how to leverage it based on the firm’s ambidexterity goals. / Business Administration/Strategic Management
35

The Role of Firm Capability, Managerial Cognition, and Ecosystem on Innovation: Investigation of The Satellite Industry

Song, Yue 22 June 2017 (has links)
In this dissertation, I systematically explore the nature and role of two firm capabilities: absorptive capacity (or external learning capability) and technological capability. I examine how firm capability interacts with intra-firm and industry factors, and how it impacts organizational outcomes. In the first paper, I review literature on absorptive capacity and distill its distinct effect on various organizational outcomes. I identify key theoretical underpinnings behind the diverse conceptualizations of absorptive capacity and their corresponding measures, and use meta-analytical techniques to synthesize the effects of absorptive capacity. The second and third papers of my dissertation examine how technological capability interacts with certain internal and external contingency factors in influencing firm innovation and industry evolution. In the second paper, I take an intra-firm focus, and I identify managerial cognition as an important internal factor that impacts the relationship between technological capability and innovation. More specifically, I study how a firm's technological competence interacts with managerial experience in shaping that firm's innovation choices. Using data from the satellite industry, I show that diversity and relatedness of technological resource, as well as CEO experience, work differently in shaping product versus application innovations. In the third paper, I investigate how capabilities beyond focal technology producers influence industry evolution. Based on longitudinal analyses of the evolution of the satellite industry, I show that complementors, component suppliers, and customers are important external factors that shape industry evolution. Overall, my dissertation demonstrates the interrelated roles of firm capability, managerial cognition, and innovation ecosystem on firm and industry-level outcomes. / Ph. D. / In this dissertation, I examine how firm capability interacts with other factors in influencing companies’ innovation decisions and the evolution of an industry. In the first paper, I review and synthesize existing studies on firm capability by focusing on the absorptive capacity (AC) literature. I identify key conceptualizations of AC, key outcomes of AC, and use meta-analytic techniques to distill AC’s effects. In the second paper, I examine how technological capability works together with managerial experience in shaping companies’ innovation choices in the small satellite industry. Small satellites, commonly defined as satellites that are less than 500 kilograms, are important innovations that substantially reduced the costs of building, launching, and operating satellites. In recent years, the small satellite industry has seen tremendous growth in terms of satellite production and deployment. I categorize innovation choices in this industry as product innovation (such as introduction of new launch systems, improved satellite components, and novel ground equipment) or application innovation (such as finding novel applications of existing satellite products by analyzing data transmitted from satellite systems and providing implications). Results show that while having related technology is positively related to product innovation, having a CEO with more diverse experience is positively related to application innovation. In the third paper, I examine how the small satellite industry emerged and evolved. Results show that beyond technological capabilities of focal small satellite manufacturers, technological advancements from complementors (launch vehicle providers) and customers (satellite operators) have jointly influenced the evolution of this industry.
36

Implementation of Refractory Foam Technology for Silencing Small IC Engines

Sesler, Josh J. 11 November 2005 (has links)
With the need for stealth in defense applications steadily increasing, noise reduction continues to play an important role in the world of aeronautics. With the ever increasing number of small UAV flight vehicle designs and their stringent weight requirements, acoustic solutions become progressively more complex. This thesis investigates the use of refractory foam, a new class of porous material, for designing effective silencers for small IC engines. The solution must be lightweight, compact, conformable, and capable of handling the rigors of flight. Throughout the course of this research, many silencer designs were fabricated to take advantage of refractory foam technology. These silencer designs were then tested against existing designs using both anechoic and outdoor testing techniques. These results proved refractory foam to be a superior broadband noise absorber that can survive harsh flight environment. Silencer designs using this material showed overall improvements in the areas of noise reduction, weight, size, and backpressure, compared to commercial designs. The final silencer design boasted an Aweighted overall sound pressure level that was 12.1 dBA lower than the reference case. This result was accomplished using nearly half the volume required by other designs to attain similar results. / Master of Science
37

Exploring the Relationship between Strategic Thinking and Absorptive Capacity: A Proposed Typology

Srivastava, Saurabh 12 1900 (has links)
Absorptive capacity plays an important role in the organizational adaptation process. Prior research on absorptive capacity focuses on its role in organizational outcomes such as financial performance, innovation, new product development, etc. Recently, scholars have called for research on factors that influence absorptive capacity. Because absorptive capacity plays a vital role in achieving organizational outcomes, it behooves us to improve our understanding of absorptive capacity and its antecedents to serve both researchers and practitioners. In this investigation, strategic thinking is posited to be a key antecedent of absorptive capacity. Capability theory suggests that strategic thinking is a metaphysical (higher order) capability that influences an organization's absorptive capacity. Combining this argument with Miles and Snow's typology of organizational adaptation process, it is posited that the relationship between strategic thinking and absorptive capacity can be clustered into different "groups." Prospectors, defenders, and analyzers, characterized in Miles and Snow's typology of firms are viewed as distinctive groups that exhibit different relationships between strategic thinking and absorptive capacity. Results from an empirical examination suggest that strategic thinking is positively related to absorptive capacity. The results also suggest that the relationship between these two constructs is different between these groups and that the strategic thinking of prospectors has a weaker relationship with absorptive capacity than other type of firms.
38

Capacidade absortiva: uma proposição para avaliação em empresas industriais

Puffal, Clair Wingert 27 May 2016 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-07-14T13:06:06Z No. of bitstreams: 1 Clair Wingert Puffal_.pdf: 838959 bytes, checksum: d0bd857e392ed3db4e5d15c5a86c82a9 (MD5) / Made available in DSpace on 2016-07-14T13:06:06Z (GMT). No. of bitstreams: 1 Clair Wingert Puffal_.pdf: 838959 bytes, checksum: d0bd857e392ed3db4e5d15c5a86c82a9 (MD5) Previous issue date: 2016-05-27 / Nenhuma / O objetivo deste estudo foi analisar processos e estruturas relacionadas às dimensões da capacidade absortiva (CA) em empresas industriais consideradas inovadoras no Rio Grande do Sul (Brasil). Para tanto, este trabalho buscou na literatura, estudos sobre o construto Capacidade Absortiva, desde sua proposição original por Cohen e Levinthal (1990) até seu aperfeiçoamento, nas últimas décadas, a partir de Zahra e George (2002), que introduziu uma visão processual das dimensões da CA e seus componentes, como CA potencial - CAp (Aquisição) e CAp (Assimilação) e CA realizada - CAr (Transformação) e CAr (Exploração), no contexto organizacional. Foram identificadas as principais contribuições em estudos anteriores sobre dimensões da CA em empresas, destacando-se os mecanismos organizacionais que apresentam elementos como coordenação, sistemas e socialização, efetividade na busca do aprendizado das empresas e sua base de conhecimento, eficácia da comunicação, interação com fontes externas de conhecimento, formalização e integração social, além de avaliações das diferentes práticas gerenciais em microprocessos das empresas, considerados recursos intangíveis para o desenvolvimento da CA. A partir desse contexto, este estudo elaborou um instrumento de coleta qualitativo, aplicado em duas empresas industriais localizadas no Rio Grande do Sul (Brasil), dotadas de processos de inovação diferenciados, comparados à concorrência em contexto local. A primeira faz parte da indústria de refrigerantes, é de grande porte e desenvolve inovações em produtos, processos e gestão, voltadas ao mercado. A segunda faz parte da indústria de equipamentos eletromédicos para estética, é de pequeno porte e desenvolve inovações com base no conhecimento tecnológico. Os resultados mostram que, por um lado, as empresas investigadas, independentemente do tamanho ou setor, mantêm uma dinâmica organizacional, com mecanismos de busca de renovação do conhecimento que envolve gestores e funcionários, com habilidades na busca e assimilação de informações externas por meio de desafios estratégicos lançados pela empresa. Por outro lado, observa–se nessas empresas dificuldade na manutenção de comunicação eficaz entre todos seus funcionários, comprometendo o desenvolvimento da CA. Este estudo preenche uma lacuna existente nas avaliações nos processos e estruturas voltadas à inovação, que podem ser aperfeiçoadas com uma perspectiva da CA, além da oportunidade de verificar na prática, como acorre o desenvolvimento da CA em empresas industriais, a partir de seus microprocessos. / The aim of this study was to analyze processes and structures related to the dimensions of absorptive capacity (ACAP) in industrial companies considered innovative in Rio Grande do Sul (Brazil). Therefore, this work sought within the literature studies on the construction of Absorptive Capacity since its original proposal by Cohen and Levinthal (1990) to its improvement in recent decades from Zahra and George (2002), which introduced a process view of the ACAP dimensions and its components as a potential ACAP - Acquisition and Assimilation, and realized RACAP - Transformation and Exploitation, in the organizational context. The main contributions in previous studies on ACAP dimensions in companies have been identified, highlighting the organizational mechanisms, which present elements such as coordination, systems and socialization, effectiveness in the pursuit of learning of the companies and their knowledge base, communication effectiveness, interaction with external sources of knowledge, formalization and social integration, besides evaluation of different management practices in micro processes of the companies, considered intangible resources to the ACAP development. This study to draw up a survey tool to collect qualitative data applied in two industrial companies located in Rio Grande do Sul, Brazil, with some innovation differentiated processes compared to the competition in local context. The first one is part of the soft drink industry; it is large-sized company and develops innovations in products, processes and management geared to the market. The second one is part of the electromedical equipment industry for cosmetic; it is small-sized company and develops innovations based on technological knowledge. In one hand the results show that regardless of size or sector the surveyed companies maintain an organizational dynamics with search mechanisms of knowledge renewal, involving managers and employees with skills in finding and assimilating external information through strategical challenges launched by the company. On the other hand, one observes in both companies difficulty in maintaining effective communication among all their employees compromising the development of ACAP. This study fulfill a gap in evaluations, in processes and in structures aimed at innovation, which can be improved with an ACAP perspective besides the opportunity of verifying in practice how the development of ACAP in industrial companies occurs from its micro processes.
39

Investigation of gasSOA formation by parcel and 3-D modeling

Gatzsche, Kathrin 02 May 2019 (has links)
Ein Großteil der Masse des troposphärischen Aerosols wird vielerorts durch organische Aerosolbestandteile gebildet. Ferner bestehen feine Aerosolpartikel bis zur Hälfte aus sekundär gebildetem organischen Aerosol (SOA). Jedoch wird die SOA-Massenkonzentration derzeit häufig durch numerische Modelle unterschätzt. Deshalb war das Ziel der vorliegenden Arbeit, die Beschreibung der SOA-Bildung durch Gas-zu-Partikel-Konversion in atmosphärischen Modellen zu verbessern, um ein besseres Verständnis der ablaufenden Prozesse und bestimmenden Parameter zu erlangen. Im hierfür verwendeten Boxmodell SPACCIM (SPectral Aerosol Cloud Chemistry Interaction Model) wurde bisher der Massentransfer zwischen der Gasphase und der organischen Partikelphase nicht beschrieben. In der vorliegenden Arbeit wurde deshalb das Modell sowohl um einen absorptiven als auch einen kinetischen Partitionierungsansatz erweitert. Wesentliche Vorteile des kinetischen Partitionierungsansatzes sind zum einen die Berücksichtigung von Eigenschaften der Aerosolphase (wie Größe und Phasenzustand der Partikel) und zum anderen Reaktionen in der Partikelphase mit einzubeziehen. Innerhalb der Arbeit wurde dieser Partitionierungsansatz weiterentwickelt, um die von der Zusammensetzung abhängige Diffusivität der Partikelphase und reversible Partikelreaktionen abbilden zu können. Weiterhin wurde das 3-D Chemie-Transport-Modell COSMO-MUSCAT (COnsortium for Small-scale MOdeling und MUlti-Scale Chemistry Aerosol Transport) mit dem kinetischen Partitionierungsansatz erweitert, um eine verbesserte Beschreibung der SOA-Bildung zu erreichen. Die Bildung von hochoxidierten, wenig flüchtigen organischen Reaktionsprodukten wurde in den jeweiligen Gasphasen-Chemiemechanismen beider Modelle implementiert. Unter Verwendung von SPACCIM mit dem absorptiven Partitionierungsansatz wurden (i) Sensitivitäten und Limitierungen der SOA-Bildung untersucht, (ii) Aerosolkammerstudien der Ozonolyse von α- und β-Pinen simuliert und (iii) der Einfluss von Wandverlusten bestimmt. Detaillierte Sensitivitätsstudien für den kinetischen Partitionierungsansatz machen deutlich, dass die Partikelreaktivität ein Schlüsselparameter ist, mit dem die SOA-Masse flüssiger Aerosolpartikel um den Faktor vier erhöht werden konnte. Weiterhin konnte gezeigt werden, dass die Partikeldiffusivität und, für halbfeste Partikel, die Partikelgröße ebenfalls bestimmende Modellparameter sind. Für Simulationen von Kammerexperimenten der Ozonolyse von α-Pinen mit mäßig schnellen Reaktionen in der Partikelphase konnte eine gute Übereinstimmung mit den gemessenen SOA-Konzentrationen erzielt werden. Dies stellt eine Verbesserung im Vergleich zum absorptiven Partitionierungsansatz dar. Des Weiteren wurde ein Experiment der AIDA-Aerosolkammer unter Verwendung einer monodispersen und einer unimodalen Aerosolverteilung simuliert. Dabei wurde, unter Berücksichtigung von mäßig schnellen oder reversiblen Reaktionen in der Partikelphase, eine gute Übereinstimmung mit den Messergebnissen für beide Verteilungen erzielt. Die Sensitivitätsstudien für den kinetischen Partitionierungsansatz haben jedoch deutlich gezeigt, dass die wichtigsten Modellparameter noch genauer aus Labormessungen charakterisiert werden müssen. Die Modellergebnisse der COSMO-MUSCAT Simulationen mit dem absorptiven Partitionierungsansatz zeigten, dass die Berücksichtigung von hochoxidierten, organischen wenig flüchtigen Reaktionsprodukten zu erhöhten SOA-Massenkonzentrationen führt und die Vaporisierungsenthalpie die SOA-Bildung deutlich beeinflusst. Außerdem wurde die Anwendbarkeit des Modellsystems mit dem kinetischen Partitionierungsansatz gezeigt und mittels einer nicht-reaktiven Partikelphase vergleichbare Ergebnisse zum absorptiven Partitionierungsansatz erzielt. Der Vergleich mit Messungen von 6 Messstationen zeigte, dass COSMO-MUSCAT in der Lage ist den zeitlichen Trend der beobachteten organischen Massenkonzentration abzubilden. Eine detailliertere Analyse für den Messort Melpitz offenbarte jedoch die zeitweise Unterschätzung der Konzentrationen von monoterpenoiden Vorläufersubstanzen insbesondere in den Nachtstunden. Dies könnte die gleichzeitig auftretende Unterschätzung der SOA-Massenkonzentration durch das Modell erklären. Die zusätzliche Berücksichtigung von Partikelphasenreaktionen erhöht zwar die SOA-Massenkonzentration in diesen Fällen, jedoch werden zuverlässige kinetische Labordaten zur Spezifizierung des jetzigen Modells und für weiterführende Studien benötigt. / In many locations, organic matter represents the largest fraction of the aerosol mass, where the aerosol fine fraction consists of up to about one-half of secondary organic aerosol (SOA). However, the SOA mass is still often underpredicted by models. Therefore, this thesis was aimed at an advanced description of SOA formation from gas-to-particle conversion in a parcel model and a 3-D chemistry transport model (CTM) to gain a better process understanding. Since the utilized parcel model SPACCIM (SPectral Aerosol Cloud Chemistry Interaction Model) has not originally comprised gas-to-particle mass transfer, this framework was further developed by both an absorptive and a kinetic partitioning approach. The latter one has the advantages to be based on aerosol bulk properties, so that particle size and phase state are considered, and to include particle reactivity. Moreover, this approach has been enhanced by a composition-dependent particle-phase diffusivity and reversible particle-phase reactions. The 3-D CTM COSMO-MUSCAT (COnsortium for Small-scale MOdeling and MUlti-Scale Chemistry Aerosol Transport) has been improved by the kinetic partitioning approach to achieve an advanced treatment of SOA formation for process studies. For both models, the respective gas-phase chemistry mechanisms were modified to consider the formation of HOMs (highly oxygenated molecules). For SPACCIM using the absorptive partitioning approach, sensitivities and limitations have been explored, aerosol chamber studies for α- and β-pinene ozonolysis have been simulated, and the impact of wall losses have been examined. Using the kinetic partitioning approach, extensive sensitivity studies have revealed the particle-phase reactivity as key parameter, with a 4-times increased SOA mass for liquid particles, followed by the particle-phase bulk diffusivity and, for semi-solid particles, the particle size. Consideration of moderate fast particle-phase reactions for the simulation of α-pinene ozonolysis exhibits an improvement to the absorptive partitioning approach because the formed SOA mass is similar to the measurements. Moreover, an AIDA chamber experiment was simulated for a monodisperse and a unimodal treatment of the aerosol distribution. For both distributions, high similarity to the measurement results have been achieved for moderate fast or reversible particle-phase reactions. Nevertheless, the sensitivity studies have been shown that the kinetic partitioning approach requires more input from laboratory studies for an appropriate characterization of the key model parameters. The model results of COSMO-MUSCAT using the absorptive partitioning approach have shown that the consideration of HOMs increases the simulated SOA mass and the enthalpy of vaporization markedly influences the formation of SOA. Moreover, the applicability of the kinetic partitioning framework has been established and, for a non-reactive particle phase, almost similar results as for the absorptive partitioning approach are achieved. Comparison with measurements from six field sites has revealed that COSMO-MUSCAT can capture the temporal course of the observed organic mass concentrations. A more detailed analysis for the field site at Melpitz has indicated a partly underestimation of measured monoterpenoid precursor concentrations particularly at nighttime, which might caused the coincident underprediction of the SOA mass concentration. The consideration of particle-phase reactions increase the SOA formation in such cases, but for a final conclusion reliable kinetic measurement data are needed as model input.
40

Application Of Absorptive Treatments On Traffic Noise Barriers In Florida

Chua, Chin Boon 01 January 2004 (has links)
In this thesis, the parallel barrier analysis feature in the Federal Highway Administration Traffic Noise Model (FHWA TNM), which is based on RAYVERB was used to explore the effects of multiple reflections due to single and parallel barriers and the use of absorptive treatment. Database was developed from the data collected from previous research efforts was used to generate a best fit equation model that can be used as a predetermining tool to determine the magnitude of parallel barrier insertion loss. The best fit equation model was then used to test against measured/model result and TNM prediction results for its validity. Absorptive materials were also studied such that 3 top of them were selected and recommended for Florida highway barrier use. It was found that the top three absorptive treatments for use on Florida highway barriers have been determined to be cementitous material, metal wool and glass fiber. These materials can be used to reduce the sound reflections for single and parallel barriers. The developed best fit equation model from this research is Deg = -2.17NRC - CW[superscript 0.42] + 1.97eln(BH) + RH[superscript 0.29] + DBB[superscript 0.27]; the prediction results give moderately high R[superscript 2] value of 0.55 if compared to the results from database. Prediction results from best fit equation model was also found to be consistent with the results from the measure/modeled results, providing further proof of the validity of the model. However, if compared results from equation model, TNM and measured/model (measured and model compared results using ANSI method), TNM was shown to provide higher insertion loss degradation. It was found that the most effective placement of absorptive material was the pattern which covers the barrier from the bottom up; it was also found that only about 60% from the bottom of the barrier area requires covering with high NRC absorptive treatment (NRC greater than or equals to 0.8) without sacrificing insertion loss. Also, if the barrier area near the top includes an easily obtainable NRC value of 0.4, only 40% to 50% of the bottom barrier needs absorptive treatment with a higher, more expensive NRC rating. These findings can substantially reduce the cost of conventional absorptive barrier which have full coverage of high NRC absorptive treatment. This research has begun important improvements in noise barrier design, additional work can be continued to further verify all the findings in this thesis such that easier and better equation model can be developed to calculate insertion loss degradation and cheaper absorptive barrier with less absorptive material usage can be built.

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