Synergistic Use of IEEE and IEC Nuclear Power Plant Standards (open access)

Synergistic Use of IEEE and IEC Nuclear Power Plant Standards

Many organizations worldwide develop standards that affect nuclear instrumentation and control (I and C). Two of the primary standards organizations are the US IEEE's Nuclear Power Engineering Committee (NPEC), and the IEC subcommittee on Reactor Instrumentation (SC45A). This paper surveys the contents of the two sets of standards. Opportunities for complementary use of IEEE and IEC standards are discussed. The collections of IEEE. and IEC standards have some overlap, but in many cases cover significantly different topics. For example, IEEE standards go to great depth on environmental qualification of many specific types of components, while IEC covers the topic only at the general level. Conversely, certain IEC standards deal with specific instrumentation and control functions, a topic area where IEEE standards are largely mute. This paper considers how the two sets of standards may be used in a complementary fashion to achieve broader topic coverage than is possible using only one or the other standard suite. To understand the similarities and differences between IEC and IEEE nuclear standards layer diagrams were developed for each set of standards. Another paper [Johnson, 2001] used the same layer diagrams to investigate where coordination between the two sets of standards is most critical.
Date: December 19, 2001
Creator: Johnson, G
System: The UNT Digital Library
Nonhomologous Mechanisms of Repair of Chromosomal Breaks (open access)

Nonhomologous Mechanisms of Repair of Chromosomal Breaks

Discovered three new proteins involved in DNA damage assessment. Interestingly they are all proteins involved in recombination, but they have very different roles in that process and other proteins that might be expected to be equivalently involved are not. This is developing into a very significant area of research.
Date: December 19, 2001
Creator: Haber, J. E.
System: The UNT Digital Library
INVENTORY ABSTRACTION (open access)

INVENTORY ABSTRACTION

The purpose of the inventory abstraction, which has been prepared in accordance with a technical work plan (CRWMS M&O 2000e for ICN 02 of the present analysis, and BSC 2001e for ICN 03 of the present analysis), is to: (1) Interpret the results of a series of relative dose calculations (CRWMS M&O 2000c, 2000f). (2) Recommend, including a basis thereof, a set of radionuclides that should be modeled in the Total System Performance Assessment in Support of the Site Recommendation (TSPA-SR) and the Total System Performance Assessment in Support of the Final Environmental Impact Statement (TSPA-FEIS). (3) Provide initial radionuclide inventories for the TSPA-SR and TSPA-FEIS models. (4) Answer the U.S. Nuclear Regulatory Commission (NRC)'s Issue Resolution Status Report ''Key Technical Issue: Container Life and Source Term'' (CLST IRSR) key technical issue (KTI): ''The rate at which radionuclides in SNF [spent nuclear fuel] are released from the EBS [engineered barrier system] through the oxidation and dissolution of spent fuel'' (NRC 1999, Subissue 3). The scope of the radionuclide screening analysis encompasses the period from 100 years to 10,000 years after the potential repository at Yucca Mountain is sealed for scenarios involving the breach of a waste package and subsequent degradation …
Date: December 19, 2001
Creator: Ragan, G.
System: The UNT Digital Library
Using Reactive Transport Modeling to Evaluate the Source Term at Yucca Mountain (open access)

Using Reactive Transport Modeling to Evaluate the Source Term at Yucca Mountain

The conventional approach of source-term evaluation for performance assessment of nuclear waste repositories uses speciation-solubility modeling tools and assumes pure phases of radioelements control their solubility. This assumption may not reflect reality, as most radioelements (except for U) may not form their own pure phases. As a result, solubility limits predicted using the conventional approach are several orders of magnitude higher then the concentrations of radioelements measured in spent fuel dissolution experiments. This paper presents the author's attempt of using a non-conventional approach to evaluate source term of radionuclide release for Yucca Mountain. Based on the general reactive-transport code AREST-CT, a model for spent fuel dissolution and secondary phase precipitation has been constructed. The model accounts for both equilibrium and kinetic reactions. Its predictions have been compared against laboratory experiments and natural analogues. It is found that without calibrations, the simulated results match laboratory and field observations very well in many aspects. More important is the fact that no contradictions between them have been found. This provides confidence in the predictive power of the model. Based on the concept of Np incorporated into uranyl minerals, the model not only predicts a lower Np source-term than that given by conventional Np …
Date: December 19, 2001
Creator: Chen, Y.
System: The UNT Digital Library
Comparison of IEC and IEEE Standards for Computer-Based Control Systems Important to Safety (open access)

Comparison of IEC and IEEE Standards for Computer-Based Control Systems Important to Safety

The collections of IEEE and 1EC standards have some overlap, but in many cases cover significantly different topics. For example, 1EEE standards go to great depth on environmental qualification of many specific types of components, while IEC covers the topic only at the general level. Conversely, certain IEC standards deal with specific instrumentation and control functions, a topic area where IEEE standards are largely mute. This paper studies two questions related to the above observations. Which standards in each body should be coordinated with each other? What opportunities exist for the two bodies to build on each other's standards to efficiently improve upon the coverage of their sets of standards? Poor coordination between the two sets of standards poses a problem for the developers of systems for plant upgrades. Developers must try to address both sets of standards to avail themselves of a sufficiently broad market. Additionally, the IEEE and IEC standards together form a more comprehensive set of guidance than either set alone. If the interfaces between the standard sets were smoother, plant staff and system designers would have a better set of tools to help in the design and specification of I and C upgrades. To understand the …
Date: December 19, 2001
Creator: Johnson, G.
System: The UNT Digital Library
Small Business Administration: Overview and Issues (open access)

Small Business Administration: Overview and Issues

None
Date: December 19, 2001
Creator: unknown
System: The UNT Digital Library
TESTING OF BASELINE AND LAMINATED FILTER DISKS USING MST AND MMST WITH A PILOT SCALE ROTARY FILTER (open access)

TESTING OF BASELINE AND LAMINATED FILTER DISKS USING MST AND MMST WITH A PILOT SCALE ROTARY FILTER

Testing was completed to compare the filtration performance of modified monosodium titanate (mMST) with that of monosodium titanate (MST) with the rotary microfilter. In addition, the performance of the new laminated filter disk was compared to that of the original baseline welded filter disk. Results showed that flux rates for mMST exceeded that of MST with both the baseline and laminated filter disks in deployment concentrations of 0.2 g/L of mMST and 0.4 g/L of MST. The filtration rate of the mMST with the laminated filter disk exceeded that of the baseline filter disk. However, the baseline filter disk filtration rate for MST was greater than that of the laminated disk. The measured sample turbidity for all tests was 1.06 NTU or less. A contract was established with SpinTek Filtration{trademark} to operate a 3-disk pilot scale unit with prototypic filter disks and various feeds and two different filter disk membranes. SpinTek evaluated a set of the baseline 0.5 micron filter disks as well as a set of laminated filter disks using the same 0.5 micron filter disks. The membrane used for both disk sets was manufactured by the Pall Corporation (PMM 050). Each set of disks was run with monosodium …
Date: December 19, 2001
Creator: Herman, D.
System: The UNT Digital Library
Small Business Administration: Overview and Issues (open access)

Small Business Administration: Overview and Issues

None
Date: December 19, 2001
Creator: Mulock, Bruce K.
System: The UNT Digital Library
Human Cloning (open access)

Human Cloning

This report provides information about the Human Cloning where a human embryo produced via cloning involves the process called somatic cell nuclear transfer. The nuclear of the egg is removed and replaced with a mature body cell.
Date: December 19, 2001
Creator: Johnson, Judith A.
System: The UNT Digital Library
Membership of the 107th Congress: A Profile (open access)

Membership of the 107th Congress: A Profile

None
Date: December 19, 2001
Creator: Amer, Mildred L.
System: The UNT Digital Library
Agroterrorism: Options in Congress (open access)

Agroterrorism: Options in Congress

Although U.S. intelligence agencies have not identified any terrorist acts targeting agricultural production (i.e., agroterrorism) in the United States to date, the events of September 11, 2001 have awakened the nation to their possibility. Some experts estimate that a single agroterrorist attack using a highly contagious livestock disease could cost between $10 billion and $30 billion to the U.S. economy. This report examines the potential threats to America’s agriculture from a deliberate biological attack, describes the current defense structure and capabilities available to respond to agroterrorism, and analyzes current congressional proposals to address the threat of biological weapons to U.S. agriculture.
Date: December 19, 2001
Creator: Segarra, Alejandro E.
System: The UNT Digital Library
National Monument Issues (open access)

National Monument Issues

None
Date: December 19, 2001
Creator: Hardy-Vincent, Carol
System: The UNT Digital Library