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The Trident of Corporate Corruption Control: Implications and Effects

Description: Corporate corruption is a widespread phenomenon that persists in the functioning of both public and private companies of differing size, performance, industry, and national origin. As it generates negative effects both within and outside the organization, corporate corruption has been the subject of scholarly research. Yet, despite attempts to understand its antecedents and consequences, companies continue to struggle to eliminate corruption in their business practices. Thus, the overarching research question for this dissertation is "Why do companies continue engaging in corruption?" To answer this research question, I focused on the topic of organizational corruption control, i.e., a set of mechanisms that purposefully target the prevention of corrupt practices within an organization. Specifically, I investigated the trident of organizational corruption control via its effects and implications on three constructs - corporate social performance, opportunity attractiveness of organizational corruption and corporate corruption recidivism. Using distinct methodologies, I examined corporate corruption control in three separate studies to address 1) the effect of corruption control on the opportunity attractiveness of organizational corruption 2) the effect of corruption control on corporate social performance and 3) the implication of ineffective corruption control on organizational corruption recidivism. Based on interdisciplinary theoretical perspectives and several secondary data sources, the hypothesized effects were empirically tested and insights were derived from a multiple case study approach. The three studies used different firm samples. Study 1 was based on the data of the United States enforcement actions for violations of the 1977 Foreign Corrupt Practice Act (FCPA) formally prohibiting foreign bribery; firm-level data from the Bloomberg terminal; and a country-level measure from Worldwide Governance Indicators. In Study 1 (N=71 firms involved in foreign bribery), results supported hypotheses that regulatory sanctioning in host countries and bureaucratic controls at a firm level were negatively correlated with corruption opportunity attractiveness. Furthermore, vigilance controls help ...
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Date: December 2018
Creator: Orudzheva, Leyla
Partner: UNT Libraries

Concentrating Solar Power (Fact Sheet)

Description: Fact sheet describing the overall capabilities of the NREL CSP Program: collector/receiver characterization, advanced reflector and absorber materials, thermal storage and advanced heat transfer fluids, and CSP modeling and analysis.
Date: August 1, 2010
Partner: UNT Libraries Government Documents Department

Research and Development for Novel Thermal Energy Storage Systems (TES) for Concentrating Solar Power (CSP)

Description: The overall objective was to develop innovative heat transfer devices and methodologies for novel thermal energy storage systems for concentrating solar power generation involving phase change materials (PCMs). Specific objectives included embedding thermosyphons and/or heat pipes (TS/HPs) within appropriate phase change materials to significantly reduce thermal resistances within the thermal energy storage system of a large-scale concentrating solar power plant and, in turn, improve performance of the plant. Experimental, system level and detailed comprehensive modeling approaches were taken to investigate the effect of adding TS/HPs on the performance of latent heat thermal energy storage (LHTES) systems.
Date: September 26, 2013
Creator: Faghri, Amir; Bergman, Theodore L & Pitchumani, Ranga
Partner: UNT Libraries Government Documents Department

Advanced Thermal Storage System with Novel Molten Salt: December 8, 2011 - April 30, 2013

Description: Final technical progress report of Halotechnics Subcontract No. NEU-2-11979-01. Halotechnics has demonstrated an advanced thermal energy storage system with a novel molten salt operating at 700 degrees C. The molten salt and storage system will enable the use of advanced power cycles such as supercritical steam and supercritical carbon dioxide in next generation CSP plants. The salt consists of low cost, earth abundant materials.
Date: May 1, 2013
Creator: Jonemann, M.
Partner: UNT Libraries Government Documents Department

10 MW Supercritical CO2 Turbine Test

Description: The Supercritical CO2 Turbine Test project was to demonstrate the inherent efficiencies of a supercritical carbon dioxide (s-CO2) power turbine and associated turbomachinery under conditions and at a scale relevant to commercial concentrating solar power (CSP) projects, thereby accelerating the commercial deployment of this new power generation technology. The project involved eight partnering organizations: NREL, Sandia National Laboratories, Echogen Power Systems, Abengoa Solar, University of Wisconsin at Madison, Electric Power Research Institute, Barber-Nichols, and the CSP Program of the U.S. Department of Energy. The multi-year project planned to design, fabricate, and validate an s-CO2 power turbine of nominally 10 MWe that is capable of operation at up to 700°C and operates in a dry-cooled test loop. The project plan consisted of three phases: (1) system design and modeling, (2) fabrication, and (3) testing. The major accomplishments of Phase 1 included: Design of a multistage, axial-flow, s-CO2 power turbine; Design modifications to an existing turbocompressor to provide s-CO2 flow for the test system; Updated equipment and installation costs for the turbomachinery and associated support infrastructure; Development of simulation tools for the test loop itself and for more efficient cycle designs that are of greater commercial interest; Simulation of s-CO2 power cycle integration into molten-nitrate-salt CSP systems indicating a cost benefit of up to 8% in levelized cost of energy; Identification of recuperator cost as a key economic parameter; Corrosion data for multiple alloys at temperatures up to 650ºC in high-pressure CO2 and recommendations for materials-of-construction; and Revised test plan and preliminary operating conditions based on the ongoing tests of related equipment. Phase 1 established that the cost of the facility needed to test the power turbine at its full power and temperature would exceed the planned funding for Phases 2 and 3. Late in Phase 1 an opportunity arose to collaborate ...
Date: January 29, 2014
Creator: Turchi, Craig
Partner: UNT Libraries Government Documents Department

Development and Demonstration of an Innovative Thermal Energy Storage System for Baseload Power Generation

Description: The objective of this project is to research and develop a thermal energy storage system (operating range 3000C – 450 0C ) based on encapsulated phase change materials (PCM) that can meet the utility-scale base-load concentrated solar power plant requirements at much lower system costs compared to the existing thermal energy storage (TES) concepts. The major focus of this program is to develop suitable encapsulation methods for existing low-cost phase change materials that would provide a cost effective and reliable solution for thermal energy storage to be integrated in solar thermal power plants. This project proposes a TES system concept that will allow for an increase of the capacity factor of the present CSP technologies to 75% or greater and reduce the cost to less than $20/kWht.
Date: September 4, 2012
Creator: Goswami, D. Y.
Partner: UNT Libraries Government Documents Department

Methodology for Constructing Reduced-Order Power Block Performance Models for CSP Applications: Preprint

Description: The inherent variability of the solar resource presents a unique challenge for CSP systems. Incident solar irradiation can fluctuate widely over a short time scale, but plant performance must be assessed for long time periods. As a result, annual simulations with hourly (or sub-hourly) timesteps are the norm in CSP analysis. A highly detailed power cycle model provides accuracy but tends to suffer from prohibitively long run-times; alternatively, simplified empirical models can run quickly but don?t always provide enough information, accuracy, or flexibility for the modeler. The ideal model for feasibility-level analysis incorporates both the detail and accuracy of a first-principle model with the low computational load of a regression model. The work presented in this paper proposes a methodology for organizing and extracting information from the performance output of a detailed model, then using it to develop a flexible reduced-order regression model in a systematic and structured way. A similar but less generalized approach for characterizing power cycle performance and a reduced-order modeling methodology for CFD analysis of heat transfer from electronic devices have been presented. This paper builds on these publications and the non-dimensional approach originally described.
Date: October 1, 2010
Creator: Wagner, M.
Partner: UNT Libraries Government Documents Department

Assessing the Impact of Heat Rejection Technology on CSP Plant Revenue: Preprint

Description: This paper explores the impact of cooling technology on revenue for hybrid-cooled plants with varying wet cooling penetration for four representative locations in the American Southwest. The impact of ACC design-point initial temperature difference (ITD - the difference between the condensing steam temperature and ambient dry-bulb) is also included in the analysis.
Date: October 1, 2010
Creator: Wagner, M. J. & Kutscher, C. F.
Partner: UNT Libraries Government Documents Department

Current TES Capabilities in TRNSYS

Description: This presentation includes: a brief overview of TRNSYS, a review of current SolarPaces models, potential of other models appropriate for CSP TES, and a review of a project proposal.
Date: February 1, 2003
Creator: Price, H. & Blair, N.
Partner: UNT Libraries Government Documents Department

Final Technical Progress Report: Development of Low-Cost Suspension Heliostat; December 7, 2011 - December 6, 2012

Description: Final technical progress report of SunShot Incubator Solaflect Energy. The project succeeded in demonstrating that the Solaflect Suspension Heliostat design is viable for large-scale CSP installations. Canting accuracy is acceptable and is continually improving as Solaflect improves its understanding of this design. Cost reduction initiatives were successful, and there are still many opportunities for further development and further cost reduction.
Date: January 1, 2013
Creator: Bender, W.
Partner: UNT Libraries Government Documents Department

Concentrating Solar Power – Central Receiver Panel Component Fabrication and Testing FINAL REPORT

Description: The objective of this project is to complete a design of an advanced concentrated solar panel and demonstrate the manufacturability of key components. Then confirm the operation of the key components under prototypic solar flux conditions. This work is an important step in reducing the levelized cost of energy (LCOE) from a central receiver solar power plant. The key technical risk to building larger power towers is building the larger receiver systems. Therefore, this proposed technology project includes the design of an advanced molten salt prototypic sub-scale receiver panel that can be utilized into a large receiver system. Then complete the fabrication and testing of key components of the receive design that will be used to validate the design. This project shall have a significant impact on solar thermal power plant design. Receiver panels of suitable size for utility scale plants are a key element to a solar power tower plant. Many subtle and complex manufacturing processes are involved in producing a reliable, robust receiver panel. Given the substantial size difference between receiver panels manufactured in the past and those needed for large plant designs, the manufacture and demonstration on prototype receiver panel components with representative features of a full-sized panel will be important to improving the build process for commercial success. Given the thermal flux limitations of the test facility, the panel components cannot be rendered full size. Significance changes occurred in the projects technical strategies from project initiation to the accomplishments described herein. The initial strategy was to define cost improvements for the receiver, design and build a scale prototype receiver and test, on sun, with a molten salt heat transport system. DOE had committed to constructing a molten salt heat transport loop to support receiver testing at the top of the NSTTF tower. Because of funding constraints ...
Date: March 30, 2013
Creator: McDowell, Michael W & Miner, Kris
Partner: UNT Libraries Government Documents Department

Utility-Scale Power Tower Solar Systems: Performance Acceptance Test Guidelines

Description: The purpose of these Guidelines is to provide direction for conducting performance acceptance testing for large power tower solar systems that can yield results of a high level of accuracy consistent with good engineering knowledge and practice. The recommendations have been developed under a National Renewable Energy Laboratory (NREL) subcontract and reviewed by stakeholders representing concerned organizations and interests throughout the concentrating solar power (CSP) community. An earlier NREL report provided similar guidelines for parabolic trough systems. These Guidelines recommend certain methods, instrumentation, equipment operating requirements, and calculation methods. When tests are run in accordance with these Guidelines, we expect that the test results will yield a valid indication of the actual performance of the tested equipment. But these are only recommendations--to be carefully considered by the contractual parties involved in the Acceptance Tests--and we expect that modifications may be required to fit the particular characteristics of a specific project.
Date: March 1, 2013
Creator: Kearney, D.
Partner: UNT Libraries Government Documents Department

Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint

Description: As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. While there are many optical tools available to measure the reflector slope errors of parabolic trough solar collectors, there are few tools to measure the absorber alignment. A new method is presented here to measure the absorber alignment in two dimensions to within 0.5 cm. The absorber alignment is measured using a digital camera and four photogrammetric targets. Physical contact with the receiver absorber or glass is not necessary. The alignment of the absorber is measured along its full length so that sagging of the absorber can be quantified with this technique. The resulting absorber alignment measurement provides critical information required to accurately determine the intercept factor of a collector.
Date: April 1, 2012
Creator: Stynes, J. K. & Ihas, B.
Partner: UNT Libraries Government Documents Department

Research and Development of a Low Cost Solar Collector

Description: This is a Final Technical Report on the Research and Development completed towards the development of a Low Cost Solar Collector conducted under the DOE cost-sharing award EE-0003591. The objective of this project was to develop a new class of solar concentrators with geometries and manufacturability that could significantly reduce the fully installed cost of the solar collector field for concentrated solar thermal power plants. The goal of the project was to achieve an aggressive cost target of $170/m2, a reduction of up to 50% in the total installed cost of a solar collector field as measured against the current industry benchmark of a conventional parabolic trough. The project plan, and the detailed activities conducted under the scope of the DOE Award project addressed all major drivers that affect solar collector costs. In addition to costs, the study also focused on evaluating technical performance of new collector architectures and compared them to the performance of the industry benchmark parabolic trough. The most notable accomplishment of this DOE award was the delivery of a full-scale integrated design, manufacturing and field installation solution for a new class of solar collector architecture which has been classified as the Bi-Planar Fresnel Collector (BPFC) and may be considered as a viable alternative to the conventional parabolic trough, as well as the conventional Fresnel collectors. This was in part accomplished through the design and development, all the way through fabrication and test validation of a new class of Linear Planar Fresnel Collector architecture. This architecture offers a number of key differentiating features which include a planar light-weight frame geometry with small mass-manufacturable elements utilizing flat mirror sections. The designs shows significant promise in reducing the material costs, fabrication costs, shipping costs, and on-site field installation costs compared to the benchmark parabolic trough, as well as the ...
Date: August 1, 2012
Creator: Ansari, Asif; Philip, Lee & Thouppuarachchi, Chirath
Partner: UNT Libraries Government Documents Department

Collector/Receiver Characterization (Fact Sheet)

Description: Fact sheet describing NREL CSP Program capabilities for collector/receiver characterization: determining optical efficiency, measuring heat loss, developing and testing concentrators, concentrating the sun's power, and optically characterizing CSP plants.
Date: August 1, 2010
Partner: UNT Libraries Government Documents Department

Visual Scanning Hartmann Optical Tester (VSHOT) Uncertainty Analysis (Milestone Report)

Description: In 1997, an uncertainty analysis was conducted of the Video Scanning Hartmann Optical Tester (VSHOT). In 2010, we have completed a new analysis, based primarily on the geometric optics of the system, and it shows sensitivities to various design and operational parameters. We discuss sources of error with measuring devices, instrument calibrations, and operator measurements for a parabolic trough mirror panel test. These help to guide the operator in proper setup, and help end-users to understand the data they are provided. We include both the systematic (bias) and random (precision) errors for VSHOT testing and their contributions to the uncertainty. The contributing factors we considered in this study are: target tilt; target face to laser output distance; instrument vertical offset; laser output angle; distance between the tool and the test piece; camera calibration; and laser scanner. These contributing factors were applied to the calculated slope error, focal length, and test article tilt that are generated by the VSHOT data processing. Results show the estimated 2-sigma uncertainty in slope error for a parabolic trough line scan test to be +/-0.2 milliradians; uncertainty in the focal length is +/- 0.1 mm, and the uncertainty in test article tilt is +/- 0.04 milliradians.
Date: October 1, 2010
Creator: Gray, A.; Lewandowski, A. & Wendelin, T.
Partner: UNT Libraries Government Documents Department