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Rapidity gaps in hard processes at D0

Description: Latest results on jet production with rapidity gaps at the Fermilab Tevatron Collider are presented. Jet production via color-singlet exchange at high momenta transfer is observed as a class of events with low particle multiplicity (or rapidity gaps) between the two highest transverse energy jets. The particle multiplicity in various regions, and the dependencies on jet pseudorapidity separation and jet transverse energy are studied for these events. Results from two classes of dijet events with one or two forward rapidity gaps are also presented. The topology of these events is consistent with expectations for hard single diffraction and hard double pomeron exchange processes, respectively.
Date: September 1, 1996
Creator: Perkins, J.
Partner: UNT Libraries Government Documents Department

Fast-wave Power Flow Along SOL Field Lines In NSTX nd The Associated Power Deposition Profile Across The SOL In Front Of The Antenna

Description: Fast-wave heating and current drive efficiencies can be reduced by a number of processes in the vicinity of the antenna and in the scrape off layer (SOL). On NSTX from around 25% to more than 60% of the high-harmonic fast-wave power can be lost to the SOL regions, and a large part of this lost power flows along SOL magnetic field lines and is deposited in bright spirals on the divertor floor and ceiling. We show that field-line mapping matches the location of heat deposition on the lower divertor, albeit with a portion of the heat outside of the predictions. The field-line mapping can then be used to partially reconstruct the profile of lost fast-wave power at the midplane in front of the antenna, and the losses peak close to the last closed flux surface (LCFS) as well as the antenna. This profile suggests a radial standing-wave pattern formed by fast-wave propagation in the SOL, and this hypothesis will be tested on NSTX-U. Advanced RF codes must reproduce these results so that such codes can be used to understand this edge loss and to minimize RF heat deposition and erosion in the divertor region on ITER.
Date: June 21, 2013
Creator: Perkins, Roy
Partner: UNT Libraries Government Documents Department

Automating the management of environmental compliance reporting: Making the complex simple

Description: Environmental compliance reporting requirements are notoriously complex. This reporting complexity is compounded by organizational and functional complexity at Rocky Mountain Arsenal (RMA), where the Department of the Army has undertaken a multi billion dollar environmental cleanup action. This site is subject to both fixed and contingent federal, state, and local reporting requirements. Management and operation of the site is characterized by numerous organizational layers, and compliance information is generated by many different contractors and subcontractors. This information must be compiled by various managers and reported to either regulators or Department of the Army offices. The RMA Environmental Compliance Office and top-level management must be assured that these reports are being promptly generated and submitted. With over 1,500 individual reporting requirements forecasted for over the next 11 years, the managerial challenge is immense. To facilitate the collation of data and issuance of compliance reports, an intranet-based database is being developed. This database is designed to be available to all personnel with access to the site's environmental compliance intranet. It presents all applicable reporting requirements in an easily sortable format. Information available for each report includes deadlines, report status, recipients, individuals responsible for report generation, and other relevant data fields. Reports can be generated that are pertinent to a specific project, office, individual, or timeframe. Because the database is an integral component of the RMA environmental compliance intranet site, reporting requirements can be linked to the regulatory or site-specific document that is driving the report. As a given report is issued, those responsible for its issuance update the database and certify that the report has been transmitted, thus enabling the RMA Environmental Compliance Office and site managers to keep real-time track of a report's status.
Date: March 9, 2000
Creator: Perkins, S.
Partner: UNT Libraries Government Documents Department

The Politics of Poverty: George Orwell's "Down and Out in Paris and London"

Description: "Down and Out in Paris and London" is typically perceived as non-political. Orwell's first book, it examines his life with the poor in two cities. Although on the surface "Down and Out" seems not to be about politics, Orwell covertly conveys a political message. This is contrary to popular critical opinion. What most critics fail to acknowledge is that Orwell wrote for a middle- and upper-class audience, showing a previously unseen view of the poor. In this he suggests change to the policy makers who are able to bring about improvements for the impoverished. "Down and Out" is often ignored by both critics and readers of Orwell. With an examination of Orwell's politicizing background, and of the way he chooses to present himself and his poor characters in "Down and Out," I argue that the book is both political and characteristic of Orwell's later work.
Date: May 1992
Creator: Perkins, Marianne
Partner: UNT Libraries

High density, high magnetic field concepts for compact fusion reactors

Description: One rather discouraging feature of our conventional approaches to fusion energy is that they do not appear to lend themselves to a small reactor for developmental purposes. This is in contrast with the normal evolution of a new technology which typically proceeds to a full scale commercial plant via a set of graduated steps. Accordingly` several concepts concerned with dense plasma fusion systems are being studied theoretically and experimentally. A common aspect is that they employ: (a) high to very high plasma densities ({approximately}10{sup 16}cm{sup -3} to {approximately}10{sup 26}cm{sup -3}) and (b) magnetic fields. If they could be shown to be viable at high fusion Q, they could conceivably lead to compact and inexpensive commercial reactors. At least, their compactness suggests that both proof of principle experiments and development costs will be relatively inexpensive compared with the present conventional approaches. In this paper, the following concepts are considered: (1) The staged Z-pinch, (2) Liner implosion of closed-field-line configurations, (3) Magnetic ``fast`` ignition of inertial fusion targets, (4) The continuous flow Z-pinch.
Date: October 11, 1996
Creator: Perkins, L. J.
Partner: UNT Libraries Government Documents Department

The restructured fusion program and the role of alternative fusion concepts

Description: This testimony to the subcommittee on Energy and the Environment of the U.S. House of Representatives`s Committee on Science pushes for about 25% of the fusion budget to go to alternative fusion concepts. These concepts are: low density magnetic confinement, inertial confinement fusion, high density magnetic confinement, and non- thermonuclear and miscellaneous programs. Various aspects of each of these concepts are outlined.
Date: March 5, 1996
Creator: Perkins, L.J.
Partner: UNT Libraries Government Documents Department

Complexity versus availability for fusion: The potential advantages of inertial fusion energy

Description: Probably the single largest advantage of the inertial route to fusion energy (IFE) is the perception that its power plant embodiments could achieve acceptable capacity factors. This is a result of its relative simplicity, the decoupling of the driver and reactor chamber, and the potential to employ thick liquid walls. We examine these issues in terms of the complexity, reliability, maintainability and, therefore, availability of both magnetic and inertial fusion power plants and compare these factors with corresponding scheduled and unscheduled outage data from present day fission experience. We stress that, given the simple nature of a fission core, the vast majority of unplanned outages in fission plants are due to failures outside the reactor vessel itself Given we must be prepared for similar outages in the analogous plant external to a fusion power core, this puts severe demands on the reliability required of the fusion core itself. We indicate that such requirements can probably be met for IFE plants. We recommend that this advantage be promoted by performing a quantitative reliability and availability study for a representative IFE power plant and suggest that databases are probably adequate for this task.
Date: September 5, 1996
Creator: Perkins, L.J.,
Partner: UNT Libraries Government Documents Department

Antiproton fast ignition for Inertial Confinement Fusion

Description: With 180MJ/{micro}g, antiprotons offer the highest stored energy per unit mass of any known entity. We investigate the use of antiprotons to promote fast ignition in an ICF capsule and seek high gains with only modest compression of the main fuel. Unlike standard fast ignition where the ignition energy is supplied by an energetic, short pulse laser, the energy here is supplied through the ionization energy deposited when antiprotons annihilate at the center of a compressed fuel capsule. In the first of two candidate fast ignition schemes, the antiproton package is delivered by a low energy external ion beam. In the second, ''autocatalytic'' scheme, the antiprotons are pre-emplaced at the center of the capsule prior to compression. In both schemes, we estimate that {approximately}3x10{sup 13} antiprotons are required to initiate fast ignition in a typical ICF capsule and show that incorporation of a thin, heavy metal shell is desirable to enhance energy deposition in the igniter zone. In addition to obviating the need for a second energetic fast laser and vulnerable final optics, this scheme would achieve central without reliance on laser channeling through halo plasma or houlrahm debris. However, in addition to the unknowns involved in the storage and manipulation of antiprotons at low energy, the other large uncertainty for the practicality of such a scheme is the ultimate efficiency of antiproton production in, an external, optimized facility.
Date: October 24, 1997
Creator: Perkins, L.J.
Partner: UNT Libraries Government Documents Department

Operational Environmental Monitoring Program Quality Assurance Project Plan

Description: This Quality Assurance Project Plan addresses the quality assurance requirements for the activities associated with the preoperational and operational environmental monitoring performed by Westinghouse Hanford Company as it implements the Operational Environmental Monitoring program. This plan applies to all sampling and monitoring activities performed by Westinghouse Hanford Company in implementing the Operational Environmental Monitoring program at the Hanford Site.
Date: August 1, 1994
Creator: Perkins, C.J.
Partner: UNT Libraries Government Documents Department


Description: The authors examine the task of pixel-by-pixel classification of the multispectral and grayscale images typically found in remote-sensing and medical applications. Simple machine learning techniques have long been applied to remote-sensed image classification, but almost always using purely spectral information about each pixel. Humans can often outperform these systems, and make extensive use of spatial context to make classification decisions. They present AFREET: an SVM-based learning system which attempts to automatically construct and refine spatio-spectral features in a somewhat human-inspired fashion. Comparisons with traditionally used machine learning techniques show that AFREET achieves significantly higher performance. The use of spatial context is particularly useful for medical imagery, where multispectral images are still rare.
Date: February 1, 2001
Creator: PERKINS, S. & HARVEY, N.
Partner: UNT Libraries Government Documents Department


Description: We consider the problem of pixel-by-pixel classification of a multi-spectral image using supervised learning. Conventional supervised classification techniques such as maximum likelihood classification and less conventional ones such as neural networks, typically base such classifications solely on the spectral components of each pixel. It is easy to see why the color of a pixel provides a nice, bounded, fixed dimensional space in which these classifiers work well. It is often the case however, that spectral information alone is not sufficient to correctly classify a pixel. Maybe spatial neighborhood information is required as well. Or may be the raw spectral components do not themselves make for easy classification, but some arithmetic combination of them would. In either of these cases we have the problem of selecting suitable spatial, spectral or spatio-spectral features that allow the classifier to do its job well. The number of all possible such features is extremely large. How can we select a suitable subset? We have developed GENIE, a hybrid learning system that combines a genetic algorithm that searches a space of image processing operations for a set that can produce suitable feature planes, and a more conventional classifier which uses those feature planes to output a final classification. In this paper we show that the use of a hybrid GA provides significant advantages over using either a GA alone or more conventional classification methods alone. We present results using high-resolution IKONOS data, looking for regions of burned forest and for roads.
Date: December 1, 2000
Creator: PERKINS, S. & AL, ET
Partner: UNT Libraries Government Documents Department

Declining Dynamism in the U.S. Labor Market

Description: This report discusses certain measures of the U.S. labor market "dynamism" or "fluidity"--including job reallocation, worker churn, and geographic labor mobility-- which some observers note have been declining for the past 20 years or more.
Date: June 15, 2016
Creator: Perkins, David W.
Partner: UNT Libraries Government Documents Department

Why Be Friends? Amicus Curiae Briefs in State Courts of Last Resort

Description: While there has been a substantial body of research on interest group activity in U.S. federal courts, there has been comparatively little analysis of interest group engagement with state courts. Given that state courts adjudicate the vast majority of cases in the American legal system and very few cases are appealed to the Supreme Court, understanding why organized interests participate in these courts is of great importance. The present study analyzes interest group involvement as amicus curiae in all state courts of last resort from 1995-1999 to examine what factors motivate organized interests to turn to the courts. The results indicate that interest groups are primarily motivated by their policy goals in deciding which cases to file amicus briefs in, but that they are limited in their ability to file by institutional constraints unique to state courts of last resort. This research provides insight into interest group behavior, state courts and the role organized interests play in influencing legal outcomes in the American states.
Date: December 2014
Creator: Perkins, Jared D.
Partner: UNT Libraries

British Pastoral Style and E.J. Moeran's Fantasy Quartet: A Lecture Recital, Together with Three Recitals of Selected Works of J.S. Bach, B. Britten, L. Foss, G. Handel, A. Marcello, E. Rubbra, C. Saint-Saens, and Others

Description: British musical style changed dramatically after 1880 primarily due to factors which may be subsumed under the general heading of nationalism. This change from an essentially Germanic style has been termed the British musical renaissance by many writers on the subject. Within this new musical language, several distinctive substyles arose. One of these, British pastoral style, has been alluded to by Frank Howes and others, but these allusions do not contribute to an understanding of the works purportedly belonging to that style. It is the purpose of this study to define British pastoral style and examine its relation to the British musical renaissance. The method employed for defining style will be that of Jan LaRue's as described in his Guidelines for Style Analysis. What is British pastoral style? Judging from the literature, British pastoral style is a type of British music written between 1900 and 1950 which evokes pastoral images, especially those associated with the British landscape. A stylistic analysis of selected works will define British pastoral style through enumeration and discussion of the style's musical constituents. A more refined definition of British pastoral style is achieved by an in-depth analysis of E. J. Moeran's Fantasy Quartet, which represents a large portion of British pastoral music, that is, works featuring the oboe. Finally, an examination of British pastoral style's relation to the British musical renaissance will reveal reasons for this particular manifestation of British musical style.
Date: August 1986
Creator: Perkins, Tedrow Lewis
Partner: UNT Libraries

Hanford site near-facility environmental monitoring annual report, calendar year 1996

Description: This document summarizes the results of the near-facility environmental monitoring results for 1996 in the 100, 200/600, and 300/400 areas of the Hanford Site in south-central Washington State. Surveillance activities included sampling and analyses of ambient air, surface water, groundwater, soil, sediments, and biota. Also, external radiation measurements and radiological surveys were taken at waste disposal sites, radiologically controlled areas, and roads. These activities were conducted to assess and control the effects of nuclear facilities and waste sites on the local environment. The monitoring implements applicable portions of DOE Orders 5400.1 (DOE 1988a), 5400.5 (DOE 1990), and 5820.2A (DOE 1988b); Washington Administrative Code (WAC) 246-247; and Title 40 Code of Federal Regulations (CFR) Part 61, Subpart H (EPA 1989). In addition, diffuse sources were monitored to determine compliance with federal, state, and/or local regulations. In general, although effects from nuclear facilities can still be observed on the Hanford Site and radiation levels were slightly elevated when compared to offsite locations, the differences are less than in previous years.
Date: August 5, 1997
Creator: Perkins, C.J.
Partner: UNT Libraries Government Documents Department

Friends of the State Courts: Organized Interests and State Courts of Last Resort

Description: Why do interest groups participate in state courts of last resort by filing amicus curiae briefs? Are they influential when they do? This dissertation examines these questions using an original survey of organized interests that routinely participate in state supreme courts, as well as data on all amicus curiae briefs and majority opinions in over 14,000 cases decided in all fifty-two state supreme courts for a four year period. I argue that interest groups turn to state judiciaries to achieve the dual goals of influencing policy and organizational maintenance, as amicus briefs can help organized interests achieve both outcomes. Furthermore, I contend that amicus briefs are influential in shaping judicial policy-making through the provision of legally persuasive arguments. The results suggest that interest groups do file amicus briefs to both lobby for their preferred policies and to support their organization's long-term viability. Additionally, the results indicate that organized interests also participate in counteractive lobbying in state courts of last resort by filing amicus briefs to ensure their side is represented and to dull the effect of oppositional amici. The findings also demonstrate support for the influence of amicus briefs on judicial policy-making on state high courts, as amicus briefs can influence the ideological direction of the court's majority opinions. Overall, this research extends our understanding of interest group lobbing in the judiciary and in state policy venues, and provides insight into judicial politics and policy-making on state courts of last resort.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: December 2016
Creator: Perkins, Jared David
Partner: UNT Libraries

Radioactive Waste Management BasisApril 2006

Description: This Radioactive Waste Management Basis (RWMB) documents radioactive waste management practices adopted at Lawrence Livermore National Laboratory (LLNL) pursuant to Department of Energy (DOE) Order 435.1, Radioactive Waste Management. The purpose of this Radioactive Waste Management Basis is to describe the systematic approach for planning, executing, and evaluating the management of radioactive waste at LLNL. The implementation of this document will ensure that waste management activities at LLNL are conducted in compliance with the requirements of DOE Order 435.1, Radioactive Waste Management, and the Implementation Guide for DOE Manual 435.1-1, Radioactive Waste Management Manual. Technical justification is provided where methods for meeting the requirements of DOE Order 435.1 deviate from the DOE Manual 435.1-1 and Implementation Guide.
Date: August 31, 2011
Creator: Perkins, B K
Partner: UNT Libraries Government Documents Department

A New Approach for the Permanent Disposal of Long Lived Fission Waste

Description: Nuclear fission can meet humanity's disparate requirements for carbon-free energy throughout this century and for millennia to come - not only for electricity but also as a source of hydrogen for transportation fuels and a heat source for desalination. However, most countries are not pursuing fission as an option for future energy and global climate needs. One paramount reason is diminished public acceptance over concerns of waste disposal. We would also add 'fuel resources' as a major future concern, because fission is not sustainable in the long term with the present 'once-through' fuel that utilizes less than 1% of the mined uranium and consigns its fertile potential to a permanent waste repository. Accordingly, global scale fission will become attainable (i.e., doable) if and when an integrated solution to this overall 'fuel-cycle' problem is realized. It is the back-end of the fuel cycle - i.e., the need for permanent storage of spent fuel and high-level waste - that has become the focus of much of the criticism. In particular, the construction and implementation of permanent waste repositories such as Yucca Mountain is becoming increasingly problematic from a financial and political perspective. The major shortcoming of these conventional repositories is that they must accommodate the whole spent fuel output from once-through fuel cycles. They are thus burdened with very large masses of material but where less than 1% is long-term, hazardous waste and where only a small fraction of the potential nuclear energy has been extracted. Second, such facilities must ensure integrity of waste containment for tens of thousands of years. Given that anything more than a few hundred years hence is unknowable and wholly unpredictable as far as future civilizations are concerned, public perception is that such facilities cannot be guaranteed to be absolutely secure for their envisaged lifetimes of tens ...
Date: March 27, 2007
Creator: Perkins, L J
Partner: UNT Libraries Government Documents Department

Flight Instrument for Measurement of Liquid-Water Content in Clouds at Temperatures Above and Below Freezing

Description: A principle formerly used in an instrument for cloud detection was further investigated to provide a simple and rapid means for measuring the liquid-water content of clouds at temperatures above and below freezing. The instrument consists of a small cylindrical element so operated at high surface temperatures that the impingement of cloud droplets creates a significant drop in the surface temperature. ? The instrument is sensitive to a wide range of liquid-water content and was calibrated at one set of fixed conditions against rotating multicylinder measurements. The limited conditions of the calibration Included an air temperature of 20 F, an air velocity of 175 miles per hour, and a surface temperature in clear air of 475 F. The results obtained from experiments conducted with the instrument indicate that the principle can be used for measurements in clouds at temperatures above and below freezing. Calibrations for ranges of airspeed, air temperature, and air density will be necessary to adapt the Instrument for general flight use.
Date: March 5, 1951
Creator: Perkins, Porter J.
Partner: UNT Libraries Government Documents Department

Icing Frequencies Experienced During Climb and Descent by Fighter-Interceptor Aircraft

Description: Data and analyses are presented on the relative frequencies of occurrence and severity of icing cloud layers encountered by jet aircraft in the climb and descent phases of flights to high altitudes. Fighter-interceptor aircraft operated by the Air Defense Command (USAF) at bases in the Duluth and Seattle areas collected the data with icing meters installed for a l-year period. The project was part of an extensive program conducted by the NACA to collect Icing cloud data for evaluating the icing problem relevant to routine operations. The average frequency of occurrence of icing was found to be about 5 percent of the number of climbs and descents during 1 year of operations The icing encounters were predominantly in the low and middle cloud layers, decreasing above 15,000 feet to practically none above 25,000 feet. The greatest thickness of ice that would accumulate on any aircraft component (as indicated by the accretion on a small object) was measured with the icing meters. The ice thicknesses on a small sensing probe averaged less than 1/32 inch and did not exceed 1/2 inch. Such accumulations are relatively small when compared with those that can form during horizontal flight in icing clouds. The light accretions resulted from relatively steep angles of flight through generally thin cloud layers. Because of the limited statistical reliability of the results, an analysis was made using previous statistics on icing clouds below an altitude of 20,000 feet to determine the general icing severity probabilities. The calculations were made using adiabatic lifting as a basis to establish the liquid-water content. Probabilities of over-all ice accretions on a small object as a function of airspeed and rate of climb were computed from the derived water contents. These results were then combined with the probability of occurrence of icing in order to ...
Date: July 1, 1958
Creator: Perkins, Porter J.
Partner: UNT Libraries Government Documents Department