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Full-Text Articles in Engineering

Surface And Sub-Surface Ablation Cell Design For Remote (Robotic) Radioactive Soil Analysis Using Laser Ablation-Inductively Coupled-Atomic Emission Spectrometry/Mass Spectrometry La-Icp-Aes/Ms , Reza Bashirzadeh Jan 1995

Surface And Sub-Surface Ablation Cell Design For Remote (Robotic) Radioactive Soil Analysis Using Laser Ablation-Inductively Coupled-Atomic Emission Spectrometry/Mass Spectrometry La-Icp-Aes/Ms , Reza Bashirzadeh

Retrospective Theses and Dissertations

There are approximately 1800 uncontrollable hazardous waste sites across the United States. The Department of Energy (DOE) is responsible for cleaning up several of these sites that were contaminated as a result of producing weapon-grade nuclear fuels in different states since the 1940s. Site characterization is the first and a very critical step in the remediation program of a radioactive contaminated site. During this process, all the necessary information about location, level, and chemical composition of the contaminated sites must be collected for the clean up planning. Ames Laboratory, one of the U.S. Department of Energy sites, has adopted ...


Analysis Of Nonlinear Modal Interaction And Its Effect On Control Performance In Stressed Power Systems Using Normal Forms Method , Chih-Ming Lin Jan 1995

Analysis Of Nonlinear Modal Interaction And Its Effect On Control Performance In Stressed Power Systems Using Normal Forms Method , Chih-Ming Lin

Retrospective Theses and Dissertations

In this research the nonlinear modal interaction and the effect of the interaction on the stressed power system dynamic behavior including excitation control performance are discussed. A systematic scheme based on the normal forms method for the determination of nonlinear interaction between fundamental modes and excitation control modes in a stressed power system is developed;In a stressed power system, the interarea mode phenomenon may occur under large disturbance. Recent investigations revealed that the interarea mode may be among the power system fundamental modes of oscillation associated with the nonlinear modal interaction. If there is significant interaction, the controls will ...


Amino Acid Composition Of Soil Organic Matter And Nitrogen Transformations In Soils Under Different Management Systems , Zachary Ngewoh Senwo Jan 1995

Amino Acid Composition Of Soil Organic Matter And Nitrogen Transformations In Soils Under Different Management Systems , Zachary Ngewoh Senwo

Retrospective Theses and Dissertations

Studies of amino acid composition of soil organic matter extracted from 10 Iowa surface soils and from surface soils of two long-term rotation experiments showed that, with the exception of asparagine plus aspartic acid and glutamine plus glutamic acid, the other 13 amino acids, expressed as percentages of total amino acid extracted, were very uniform among the soils. The total amino acid extracted was significantly correlated with organic C (r = 0.79[superscript]\*\*) and clay content (r = 0.76[superscript]\*\*), but not with total N. Expressed as percentages of organic C and N in soils, the amounts extracted ranged from ...


Total System Performance Assessment Of The Proposed High Level Radioactive Waste Repository Site At Genting Island, Karimunjawa, Indonesia , Yudi Utomo Imardjoko Jan 1995

Total System Performance Assessment Of The Proposed High Level Radioactive Waste Repository Site At Genting Island, Karimunjawa, Indonesia , Yudi Utomo Imardjoko

Retrospective Theses and Dissertations

Indonesia is about to enter the nuclear era by building several nuclear power plants in the near future. Numerous issues must be addressed to evaluate the impact on the environment of high-level radioactive waste (HLRW) generated by these plants. This consideration of HLRW management must be done in a timely manner;This dissertation discusses the methodology for the Genting repository site development plan. The approach to the development of the repository is divided into three main areas, the inventory of HLRW, the barrier systems (natural and engineered), and the physical conditions of the site. The radionuclide inventory and waste form ...


Measuring And Modeling Alachlor Dissipation In Soil , Dee Anna Jo Weed Jan 1995

Measuring And Modeling Alachlor Dissipation In Soil , Dee Anna Jo Weed

Retrospective Theses and Dissertations

Field and laboratory experiments evaluated the overall dissipation of alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl) acetamide) and the effect of no-till and chisel-plow tillages on alachlor leaching and dissipation. In the top 30-cm layer of field soil, the time to 50% dissipation (half-life) was 2 to 3 d, and the time to 90% dissipation ranged from 17 to 30 d. In no-till soil, alachlor dissipated slightly faster, and more was transported into the 10-to-30-cm soil layer. The tillage effect depended on weather that favored movement into and dissipation within the soil, rather than dissipation on plant residues and the soil ...


Genetic-Based Unit Commitment Algorithm , Timothy Trent Maifeld Jan 1995

Genetic-Based Unit Commitment Algorithm , Timothy Trent Maifeld

Retrospective Theses and Dissertations

The National Energy Policy Act of 1992 allows open access to transmission lines. The electric utility industry is in the transition from operating in a monopolistic environment to one that is less regulated. For an electric utility to operate in this new environment, a new algorithm is needed to optimally schedule generating units in the needed response time of an electric power broker. Past methods of unit commitment scheduling are either too computationally slow or do not produce optimal unit commitment schedules. Unit commitment scheduling is the problem of determining the optimal set of generating units within a power system ...


Electronic And Photonic Devices: Experimental Investigations Of Hydrogenated Amorphous Silicon Substrate N+/I/P+ Solar Cell And Fundamental Properties Of Quantum Wells With Cylindrical Geometry And Applications To Electronics And Photonics , Er-Xuan Ping Jan 1995

Electronic And Photonic Devices: Experimental Investigations Of Hydrogenated Amorphous Silicon Substrate N+/I/P+ Solar Cell And Fundamental Properties Of Quantum Wells With Cylindrical Geometry And Applications To Electronics And Photonics , Er-Xuan Ping

Retrospective Theses and Dissertations

This thesis consists of two different parts: (I) experimental investigations of hydrogenated amorphous silicon substrate n[superscript]+/i/p[superscript]+ solar cells and, (II) fundamental properties of quantum wells with cylindrical geometry and applications to electronics and photonics;Part I. The substrate structural n[superscript]+/i/p[superscript]+ solar cells based on a-Si:H materials are fabricated by a radio frequency (RF) triode geometric plasma enhanced chemical vapor deposition (PECVD) system. The solar cells have been electrically and optically tested. Two different substrates, tin-oxide coated glass and stainless steel foil, are used. An RF magnetron sputtering system is used to ...


Market-Based Allocation Mechanisms For Lot-Size Decision Makers And Electric Power Utilities , Cheng-Kang Chen Jan 1995

Market-Based Allocation Mechanisms For Lot-Size Decision Makers And Electric Power Utilities , Cheng-Kang Chen

Retrospective Theses and Dissertations

The objective of this dissertation is to investigate how lot-size decision makers and electric power utilities determine critical economic quantities (e.g., the order quantities for the lot-size decision makers and the transmission service charges for the electric power utilities). A primary motivation of this study is to improve the economic efficiency (often measured in terms of cost saving) for lot-size decision makers and electric power utilities;For lot-size decision makers, we extend the traditional economic order quantity (EOQ) model by considering various aspects of model environments such as pricing policies. First, we investigate the inventory and disposal policies for ...


Performance Assessment Modeling Of Alternative High Level Nuclear Wasteforms , William Mark Nutt Jan 1995

Performance Assessment Modeling Of Alternative High Level Nuclear Wasteforms , William Mark Nutt

Retrospective Theses and Dissertations

Performance assessment (PA) analyses have been completed for high level nuclear waste forms derived from once through Light Water Reactor (LWR) spent fuel (SF), defense high level waste (DHLW), the closed advanced liquid metal reactor (ALMR) pyroprocess fuel cycle, and the front end processing of LWR spent fuel for possible recycling of the actinides in the closed ALMR fuel cycle. The IMARC (Integrated Multiple Assumptions and Release Calculations) and RIP (Repository Integration Program) PA tools were utilized to predict the performance of these wasteforms for emplacement in the proposed Yucca Mountain Repository;A model was developed to predict the time ...


Propagation Of Uncertainty In A Knowledge-Based System To Assess Energy Management Strategies For New Technologies , Chun-Yen Hsu Jan 1995

Propagation Of Uncertainty In A Knowledge-Based System To Assess Energy Management Strategies For New Technologies , Chun-Yen Hsu

Retrospective Theses and Dissertations

The goal of this project is to investigate the propagation of uncertainty in a knowledge-based system that assesses energy management strategies for new gas and electric technologies that can help reduce energy consumption and demand. The new technologies that have been investigated include lighting, electric heat pumps, motors, refrigerators, microwave clothes dryers, freeze concentration, electric vehicles, gas furnaces, gas heat pumps, engine-driven chillers, absorption chillers, and natural gas vehicles distributed throughout the residential, commercial, industrial, and transportation sectors;The description of a complex assessment system may be simplified by allowing some degree of uncertainty. A number of uncertainty-representing mechanisms, such ...