Sample records for efficient spectrum utilization

  1. Improving VHF Spectrum Utilization

    NASA Technical Reports Server (NTRS)

    Andro, Monty; Orr, Richard; Foore, Larry; Sheehe, Charles; Freeman, Mark; Nguyen, Thanh; Bretmersky, Steven; Laberge, Chuck; Buchanan, David

    2004-01-01

    Limited VHF communications system capacity and increasing air traffic results in congestion of the aviation VHF spectrum. The voice communications errors and delayed channel access create system congestion and air traffic delays. Regulatory subdivision of bands for specific functions limits flexibility in the frequency usage. The objective of this viewgraph presentation is to identify near/mid/far term technologies to improve the performance and spectrum efficiency of current and emerging VHF communications systems. Select technologies with the highest potential, perform research and development to bring them to implementation stage.

  2. Utilization and Fairness in Spectrum Assignment for Opportunistic Spectrum Access

    E-print Network

    Almeroth, Kevin C.

    1 Utilization and Fairness in Spectrum Assignment for Opportunistic Spectrum Access Chunyi Peng, Haitao Zheng, Ben Y. Zhao Abstract-- The Open Spectrum approach to spectrum access can achieve near-optimal utilization by allowing devices to sense and utilize available spectrum opportunistically. However, a naive

  3. Utilization and Fairness in Spectrum Assignment for Opportunistic Spectrum Access

    E-print Network

    Zhao, Ben Y.

    1 Utilization and Fairness in Spectrum Assignment for Opportunistic Spectrum Access Chunyi Peng, Haitao Zheng, Ben Y. Zhao Abstract--- The Open Spectrum approach to spectrum access can achieve near­optimal utilization by allowing devices to sense and utilize available spectrum opportunistically. However, a naive

  4. 47 CFR 101.521 - Spectrum utilization.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Telecommunication 5 2014-10-01 2014-10-01 false Spectrum utilization. 101.521 Section 101.521 Telecommunication...Service and Digital Electronic Message Service § 101.521 Spectrum utilization. All applicants for DEMS...

  5. 47 CFR 101.521 - Spectrum utilization.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Telecommunication 5 2013-10-01 2013-10-01 false Spectrum utilization. 101.521 Section 101.521 Telecommunication...Service and Digital Electronic Message Service § 101.521 Spectrum utilization. All applicants for DEMS...

  6. 47 CFR 101.521 - Spectrum utilization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Telecommunication 5 2010-10-01 2010-10-01 false Spectrum utilization. 101.521 Section 101.521 Telecommunication...Service and Digital Electronic Message Service § 101.521 Spectrum utilization. All applicants for DEMS...

  7. 47 CFR 101.521 - Spectrum utilization.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Telecommunication 5 2012-10-01 2012-10-01 false Spectrum utilization. 101.521 Section 101.521 Telecommunication...Service and Digital Electronic Message Service § 101.521 Spectrum utilization. All applicants for DEMS...

  8. High efficiency laser spectrum conditioner

    DOEpatents

    Greiner, Norman R. (Los Alamos, NM)

    1980-01-01

    A high efficiency laser spectrum conditioner for generating a collinear parallel output beam containing a predetermined set of frequencies from a multifrequency laser. A diffraction grating and spherical mirror are used in combination, to disperse the various frequencies of the input laser beam and direct these frequencies along various parallel lines spatially separated from one another to an apertured mask. Selection of the desired frequencies is accomplished by placement of apertures at locations on the mask where the desired frequencies intersect the mask. A recollimated parallel output beam with the desired set of frequencies is subsequently generated utilizing a mirror and grating matched and geometrically aligned in the same manner as the input grating and mirror.

  9. Towards Cognitive Radio Networks: Spectrum Utilization Measurements in Suburb Environment

    E-print Network

    Paris-Sud XI, Université de

    Towards Cognitive Radio Networks: Spectrum Utilization Measurements in Suburb Environment Václav or more utilized licensed frequency bands that could be possibly used by cognitive radios in an opportunistic way. Cognitive radio concept for better spectrum utilization is introduced here along

  10. Spectrum-orbit utilization - An overview. [domestic satellite communication systems

    NASA Technical Reports Server (NTRS)

    Sawitz, P. H.

    1975-01-01

    This paper discusses the problems associated with the efficient utilization of the natural resources of frequency spectrum and geo-stationary orbital arc. The nature of these resources is explained and their quantities are estimated. The present and projected future demand for them is given, and the problem areas are identified and discussed. Special emphasis is placed on mutual interference, launch limitations, propagation effects, and operational restrictions. The technical factors bearing on these problems, such as antenna patterns, modulation methods, emission restrictions, equipment characteristics, and system requirements, are discussed in detail. Some important trade-offs are presented, and special techniques that can be used to increase spectrum-orbit utilization are described. Particular emphasis is given throughout to U.S. domestic satellite communication systems.

  11. Enhancing spectrum utilization through cooperation and cognition in wireless systems

    E-print Network

    Rahul, Hariharan Shankar, 1975-

    2013-01-01

    We have seen a proliferation of wireless technologies and devices in recent years. The resulting explosion of wireless demand has put immense pressure on available spectrum. Improving spectrum utilization is therefore ...

  12. Spectrum efficiency of GMSK land mobile radio

    Microsoft Academic Search

    K. Murota

    1985-01-01

    Gaussian-filtered minimum-shift keying (GMSK) is a constant envelope and narrow-band modulation suitable for power- and band-limited digital radio communication. From the viewpoint of efficient spectrum use by land mobile radio, geographical reuse of cochannels as well as power spectrum compactness are desired. The output power spectrum of GMSK modulation can be made compact, at a sacrifice of co-channel interference protection.

  13. Green Wireless Cognition: Future Efficient Spectrum Sharing

    E-print Network

    Shihada, Basem

    connectivity is a must. Dense, smallrange wireless access points (AP) will become more important than todayGreen Wireless Cognition: Future Efficient Spectrum Sharing Prof. Basem Shihada MCSE 1 2nd Annual and applications will live in the cloud. Users can access them anytime, anywhere. Ubiquitous highspeed wireless

  14. RISM: An Efficient Spectrum Management System for Underwater Cognitive Acoustic Networks

    E-print Network

    Zhou, Shengli

    -utilization is caused by directional transmissions and receptions of acoustic systems [5]. To improve the efficiencyRISM: An Efficient Spectrum Management System for Underwater Cognitive Acoustic Networks Yu Luo-- Cognitive acoustic (CA) is emerging as a promising technique for environment-friendly and spectrum

  15. 75 FR 81558 - Promoting More Efficient Use of Spectrum Through Dynamic Spectrum Use Technologies

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ...FCC 10-198] Promoting More Efficient Use of Spectrum Through Dynamic Spectrum Use Technologies AGENCY: Federal Communications...innovation to ensure that the promise of dynamic spectrum access technologies can be fully realized...

  16. The effects of geography on spectrum-orbit utilization

    NASA Technical Reports Server (NTRS)

    Sawitz, P. H.

    1979-01-01

    With over forty satellites in geostationary orbit, and many more planned, it is becoming increasingly difficult to find suitable orbit positions for new systems operating at 4 and 6 GHz. Efficient spectrum-orbit utilization can be achieved with frequency-reuse techniques - orthogonal polarization, earth-station antenna discrimination, and satellite antenna discrimination - provided that service-area geography is considered. Service arc - that portion of the orbit which affords useful service to all points in a given area - is a function of the area's climate, terrain, and location as well as its size and shape. Of the three techniques, satellite antenna discrimination is the most sensitive to these factors. According to the BSS (broadcasting-satellite service) antenna reference pattern, the maximum discrimination possible is the on-axis gain, which can be as high as 49 dB for a beamwidth of 0.6 degrees, or as low as 32 dB for a 3.5-degree beamwidth. Unlike the Fixed-Satellite Service (FSS), the BSS will normally have beams that cover no more than one or two time zones.

  17. Spectrum Efficiency & Mesh Networks Asipita M. Omuya, Lionel Sacks

    E-print Network

    Haddadi, Hamed

    Spectrum Efficiency & Mesh Networks Asipita M. Omuya, Lionel Sacks University College London ABSTRACT: This paper examines the issues affecting the efficient use of spectrum. It looks at the origins ­ the use of spectrum as a commons ­ with particular emphasis on Mesh networks and how they might influence

  18. Planning satellite communication services and spectrum-orbit utilization

    NASA Technical Reports Server (NTRS)

    Sawitz, P. H.

    1982-01-01

    The relationship between approaches to planning satellite communication services and spectrum-orbit utilization is considered, with emphasis on the fixed-satellite and the broadcasting-satellite services. It is noted that there are several possible approaches to planning space services, differing principally in the rigidity with which technical parameters are prescribed, in the time for which a plan remains in force, and in the procedures adopted for implementation and modifications. With some planning approaches, spectrum-orbit utilization is fixed at the time the plan is made. Others provide for greater flexibility by making it possible to postpone some decisions on technical parameters. In addition, the two political questions of what is equitable access and how it can be guaranteed in practice play an important role.

  19. A Proposal for Efficient Use of the Television Spectrum

    E-print Network

    Weiss, Martin

    2002-07-22

    It is widely recognized that broadcast spectrum is utilized inefficiently. The principle technical cause of this inefficiency is inexpensive receiver design. In addition, the economics of the industry are such that users ...

  20. Spectrum pooling: an innovative strategy for the enhancement of spectrum efficiency

    Microsoft Academic Search

    T. A. Weiss; F. K. Jondral

    2004-01-01

    This article describes the technical challenges that have to be met when implementing the interesting new technology of spectrum pooling. This notion represents the coexistence of two mobile radio systems within the same frequency range. It enables the secondary utilization of already licensed frequency bands as aimed at by several regulatory authorities worldwide. The goal of spectrum pooling is to

  1. Spectrum efficiency of a mobile cellular radio system using direct sequence spread spectrum

    Microsoft Academic Search

    Howard Sewberath Misser; Ramjee Prasad

    1991-01-01

    Direct Sequence Spread Spectrum Muitiple Access (DS\\/SSMA) is proposed for mobile cellular systems with coherent phase shift keying (CPSK) modulation. Spectrum efficiency and bit error probability are evaluated taking co-channel interference into account for uncorrelated (fast) Rayleigh fading and (slow) log-noma1 shadowed signals, The analysis is significant for a mobile radio system using Direct Sequence Spread Spectrum because in such

  2. Requisites to realize high conversion efficiency of solar cells utilizing carrier multiplication

    Microsoft Academic Search

    Yasuhiko Takeda; Tomoyoshi Motohiro

    2010-01-01

    We have calculated the limiting conversion efficiency of solar cells utilizing carrier multiplication (CM), using the detailed balance theory. The solar cells were assumed to comprise quantum dots (QDs) embedded in another material. It has been elucidated that three requisites must be fulfilled, so that a sufficient number of photons in the solar spectrum contribute to CM, resulting in significantly

  3. Nitrogen utilization efficiency in sorghum cultivars 

    E-print Network

    Reed, Stewart Thomas

    1990-01-01

    . Experimental Design and Cultural Practices. Sample Preparation and Analytical Procedures. . . . . . . . IV RESULTS AND DISCUSSION. 16 Yearly Observations Biomass Dry Weight at Boot. . . . . . . . . . , . . . . . . Total N Uptake at Boot Nitrogen Use... Efficiency (NE1) at Boot. . . . . . Total Biomass Dry Weight at Harvest. . . . . . . . Total N Uptake at Harvest Nitrogen Use Efficiency (NE1) at Harvest. . . Grain Production and Nitrogen Efficiency. . . Distribution of N and Dry Weight Within the Plant...

  4. 47 CFR 90.535 - Modulation and spectrum usage efficiency requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Modulation and spectrum usage efficiency requirements. 90...MHz Bands § 90.535 Modulation and spectrum usage efficiency requirements. ...least one voice path per 6.25 kHz of spectrum bandwidth. (2) Licensees...

  5. 47 CFR 90.535 - Modulation and spectrum usage efficiency requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Modulation and spectrum usage efficiency requirements. 90...MHz Bands § 90.535 Modulation and spectrum usage efficiency requirements. ...least one voice path per 6.25 kHz of spectrum bandwidth. (2) Licensees...

  6. 47 CFR 90.535 - Modulation and spectrum usage efficiency requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Modulation and spectrum usage efficiency requirements. 90...MHz Bands § 90.535 Modulation and spectrum usage efficiency requirements. ...least one voice path per 6.25 kHz of spectrum bandwidth. (2) Licensees...

  7. 47 CFR 90.535 - Modulation and spectrum usage efficiency requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Modulation and spectrum usage efficiency requirements. 90...MHz Bands § 90.535 Modulation and spectrum usage efficiency requirements. ...least one voice path per 6.25 kHz of spectrum bandwidth. (2) Licensees...

  8. Maximizing the utility of radio spectrum: Broadband spectrum measurements and occupancy model for use by cognitive radio

    NASA Astrophysics Data System (ADS)

    Petrin, Allen J.

    Radio spectrum is a vital national asset; proper management of this finite resource is essential to the operation and development of telecommunications, radio-navigation, radio astronomy, and passive remote sensing services. To maximize the utility of the radio spectrum, knowledge of its current usage is beneficial. As a result, several spectrum studies have been conducted in urban Atlanta, suburban Atlanta, and rural North Carolina. These studies improve upon past spectrum studies by resolving spectrum usage by nearly all its possible parameters: frequency, time, polarization, azimuth, and location type. The continuous frequency range from 400MHz to 7.2 GHz was measured with a custom-designed system. More than 8 billion spectrum measurements were taken over several months of observation. A multi-parameter spectrum usage detection method was developed and analyzed with data from the spectrum studies. This method was designed to exploit all the characteristics of spectral information that was available from the spectrum studies. Analysis of the spectrum studies showed significant levels of underuse. The level of spectrum usage in time and azimuthal space was determined to be only 6.5 % for the urban Atlanta, 5.3 % for suburban Atlanta, and 0.8 % for the rural North Carolina spectrum studies. Most of the frequencies measured never experienced usage. Interference was detected in several protected radio astronomy and sensitive radio navigation bands. A cognitive radio network architecture to share spectrum with fixed microwave systems was developed. The architecture uses a broker-based sharing method to control spectrum access and investigate interference issues.

  9. 75 FR 70725 - Spectrum Policy Seminar for the Utility Sector

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-18

    ...Communications Requirements of Smart Grid Technologies. '' The complete text...issues arising from the deployment of smart grid technologies, can be found at...surely play in the deployment of smart grid technologies. At this spectrum...

  10. Analysis of Spectrum Utilization in Suburb Environment Evaluation of Potentials for Cognitive Radio

    E-print Network

    Paris-Sud XI, Université de

    exist sporadically utilized licensed frequency bands that could be possibly used by cognitive radios in an opportunistic way. Cognitive radio concept for better spectrum utilization is introduced here along of the Cognitive Radio (CR) concept, a technology that envisages a flexible access to unused or underutilized

  11. The Performance of a Direct Sequence Spread Spectrum Cdma System Utilizing Unequal Carrier Frequencies

    Microsoft Academic Search

    Elvino S. Sousa

    1992-01-01

    In this paper we determine the performance of a direct sequence spread spectrum multiple access system where the users utilize different carrier frequencies. This scheme is applicable to a system, such as an indoor wireless communication system utilizing very high frequencies, where the available bandwidth is so large that it is not feasible to spread the signal over the whole

  12. Visible-frequency metasurfaces for broadband anomalous reflection and high-efficiency spectrum splitting

    E-print Network

    Li, Zhongyang; Butun, Serkan; Aydin, Koray

    2014-01-01

    Ultrathin metasurfaces have recently emerged as promising materials to enable novel, flat optical components and surface-confined, miniature photonic devices. However, experimental realization of high-performance metasurfaces at visible frequencies has been a significant challenge due to high plasmonic losses and difficulties in high-uniformity nanofabrication. Here, we propose a highly-efficient yet simple metasurface design comprising of single gradient antenna as unit cell. We demonstrate visible broadband (450 - 850 nm) anomalous reflection and spectrum splitting with 85% conversion efficiency. Average power ratio of anomalous reflection to the strongest diffraction was calculated to be ~ 103 and measured to be ~ 10. The anomalous reflected photons and spectrum splitting performance have been visualized using CCD and characterized using angle-resolved measurement setup. Metasurface design proposed here is a clear departure from conventional metasurfaces utilizing multiple, anisotropic resonators, and coul...

  13. The utility of rodent models of autism spectrum disorders

    PubMed Central

    Lazaro, Maria; Golshani, Peyman

    2015-01-01

    Purpose of Review This review discusses the ways rodent models of autism spectrum disorders (ASDs) have been used to gain critical information convergent molecular pathways, the mechanisms underlying altered microcircuit structure and function, and as a screen for potential cutting edge-treatments. Recent Findings There is convergent evidence that impaired developmental pruning of connections may be a common finding among several mouse models of ASDs. Recent studies have uncovered impaired autophagy by pathological mTOR activation as a potential contributor to microcircuit dysfunction and behavior. ASD related disinhibition and exaggerated synaptic plasticity in multiple distinct circuits in cortex and reward circuits in striatum also contribute to social dysfunction and repetitive behaviors. New exciting molecular therapeutic techniques have reversed cognitive deficits in models of ASD, indicating that mouse models could be used for preclinical translational studies of new treatments. Summary Rodent models of ASDs coupled to new emerging technologies for genome editing, cell-specific functional and structural imaging, and neuronal activity manipulation will yield critical insights into ASD pathogenesis and fuel the emergence of new treatments. PMID:25734952

  14. Utility investments in low-income-energy-efficiency programs

    SciTech Connect

    Brown, M.A. [Oak Ridge National Lab., TN (United States); Beyer, M.A. [Aspen Systems Corp., Oak Ridge, TN (United States); Eisenberg, J.; Power, M. [Economic Opportunity Research Institute, Washington, DC (United States); Lapsa, E.J. [Manhattan Data Systems, Knoxville, TN (United States)

    1994-09-01

    The objective of this study is to describe the energy-efficiency programs being operated by utilities for low-income customers. The study focuses, in particular, on programs that install major residential weatherization measures free-of-charge to low-income households. A survey was mailed to a targeted list of 600 utility program managers. Follow-up telephone calls were made to key non- respondents, and a random sample of other non-respondents also was contacted. Completed surveys were received from 180 utilities, 95 of which provided information on one or more of their 1992 low-income energy-efficiency programs for a total of 132 individual programs. These 132 utility programs spent a total of $140.6 million in 1992. This represents 27% of the total program resources available to weatherize the dwellings of low-income households in that year. Both the total funding and the number of programs has grown by 29% since 1989. A majority of the 132 programs are concentrated in a few regions of the country (California, the Pacific Northwest, the Upper Midwest, and the Northeast). Although a majority of the programs are funded by electric utilities, gas utilities have a significantly greater average expenditure per participant ($864 vs. $307 per participant). The most common primary goal of low-income energy-efficiency programs operating in 1992 was {open_quotes}to make energy services more affordable to low-income customers{close_quotes}. Only 44% of the programs were operated primarily to provide a cost-effective energy resource. Based on a review of household and measure selection criteria, equity and not the efficiency of resource acquisition appears to dominate the design of these programs.

  15. Luminous power efficiency optimization of a white organic light-emitting diode by tuning its spectrum and its extraction efficiency

    Microsoft Academic Search

    Peter Vandersteegen; Gregor Schwartz; Peter Bienstman; Roel Baets

    2008-01-01

    We show an increase of the luminous power efficiency of a white organic light-emitting diode (LED) with three emitters by optimizing its spectrum and its extraction efficiency. To calculate this efficiency we use a model with four parameters: the spectra, extraction efficiencies, internal quantum efficiencies of three emitters, and the driving voltage. This luminous power efficiency increases by 30% by

  16. BINGO: a code for the efficient computation of the scalar bi-spectrum

    SciTech Connect

    Hazra, Dhiraj Kumar [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211019 (India); Sriramkumar, L. [Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India); Martin, Jérôme, E-mail: dhiraj@apctp.org, E-mail: sriram@physics.iitm.ac.in, E-mail: jmartin@iap.fr [Institut d'Astrophysique de Paris, UMR7095-CNRS, Université Pierre et Marie Curie, 98bis boulevard Arago, 75014 Paris (France)

    2013-05-01

    We present a new and accurate Fortran code, the BI-spectra and Non-Gaussianity Operator (BINGO), for the efficient numerical computation of the scalar bi-spectrum and the non-Gaussianity parameter f{sub NL} in single field inflationary models involving the canonical scalar field. The code can calculate all the different contributions to the bi-spectrum and the parameter f{sub NL} for an arbitrary triangular configuration of the wavevectors. Focusing firstly on the equilateral limit, we illustrate the accuracy of BINGO by comparing the results from the code with the spectral dependence of the bi-spectrum expected in power law inflation. Then, considering an arbitrary triangular configuration, we contrast the numerical results with the analytical expression available in the slow roll limit, for, say, the case of the conventional quadratic potential. Considering a non-trivial scenario involving deviations from slow roll, we compare the results from the code with the analytical results that have recently been obtained in the case of the Starobinsky model in the equilateral limit. As an immediate application, we utilize BINGO to examine of the power of the non-Gaussianity parameter f{sub NL} to discriminate between various inflationary models that admit departures from slow roll and lead to similar features in the scalar power spectrum. We close with a summary and discussion on the implications of the results we obtain.

  17. Spread spectrum microwave power generation for improving efficiency

    SciTech Connect

    Van Loock, W.M. [Univ. of Ghent (Belgium)

    1996-12-31

    Microwave power for heating applications is normally generated in the designated ISM frequency bands which occupy a band of 4%. Actual microwave generators, such as are used in domestic ovens utilize only a small fraction of this bandwidth. It is being demonstrated that spreading the power uniformly over the full ISM band by controlled frequency modulation dramatically reduces all levels of potential electromagnetic interference. With such controlled modulation telecommunication channels can operate within the ISM bands without serious problems because the leakage levels are reduced by 20 to 30 dB with no additional shielding costs. One simple (though not optimum) modulating waveform is a large ripple voltage on the magnetron power supply. Frequency modulation that spreads the energy over the full ISM band also improves the overall energy efficiency in multimode heating applications.

  18. Robust Distributed Spectrum Sensing in Cognitive Radio Networks

    Microsoft Academic Search

    Ruiliang Chen; Jung-Min Park; Kaigui Bian

    2008-01-01

    Cognitive radio is an enabling technology for efficient utilization of radio spectrum. A key function of cognitive radios is spectrum sensing, which enables secondary users to identify vacant spectrum not used by primary users (a.k.a. spectrum \\

  19. Visible-frequency metasurfaces for broadband anomalous reflection and high-efficiency spectrum splitting.

    PubMed

    Li, Zhongyang; Palacios, Edgar; Butun, Serkan; Aydin, Koray

    2015-03-11

    Ultrathin metasurfaces have recently emerged as promising materials that have huge potential to enable novel, flat optical components, and surface-confined, miniature photonic devices. Metasurfaces offer new degrees of freedom in molding the optical wavefronts by introducing abrupt and drastic changes in the amplitude, phase, and/or polarization of electromagnetic radiation at the wavelength scale. By carefully arranging multiple subwavelength anisotropic or gradient optical resonators, metasurfaces have been shown to enable anomalous transmission, anomalous reflection, optical holograms, and spin-orbit interaction. However, experimental realization of high-performance metasurfaces that can operate at visible frequency range has been a significant challenge due to high optical losses of plasmonic materials and difficulties in fabricating several plasmonic resonators of subwavelength size with high uniformity. Here, we propose a highly efficient yet a simple metasurface design comprising of a single, anisotropic silver antenna in its unit cell. We demonstrate broadband (450-850 nm) anomalous reflection and spectrum splitting at visible and near-IR frequencies with high conversion efficiency. Average power ratio of anomalous reflection to the strongest diffraction mode was calculated to be on the order of 10(3) and measured to be on the order of 10. The anomalous reflected photons have been visualized using a charge-coupled device camera, and broadband spectrum splitting performance has been confirmed experimentally using a free space, angle-resolved reflection measurement setup. Metasurface design proposed in this study is a clear departure from conventional metasurfaces utilizing multiple, anisotropic and/or gradient optical resonators and could enable high-efficiency, broadband metasurfaces for achieving flat high signal-to-noise ratio optical spectrometers, polarization beam splitters, directional emitters, and spectrum splitting surfaces for photovoltaics. PMID:25664815

  20. Implications of the Public Utility Regulatory Act for Energy Efficiency in Texas 

    E-print Network

    Biedrzycki, C. J.

    1985-01-01

    electric utilities contain provisions requiring certain electric utilities to prepare energy efficiency plans. In their plans, utilities must consider the potential for economically producing capacity through supply-side and demand-side alternatives to new...

  1. Best Practices Implementation for Hydropower Efficiency and Utilization Improvement

    SciTech Connect

    Smith, Brennan T [ORNL] [ORNL; Zhang, Qin Fen [ORNL] [ORNL; March, Patrick [Hydro Performance Processes, Inc.] [Hydro Performance Processes, Inc.; Cones, Marvin [Mesa Associates, Inc.] [Mesa Associates, Inc.; Dham, Rajesh [U.S. Department of Energy] [U.S. Department of Energy; Spray, Michael [New West Technologies, LLC.] [New West Technologies, LLC.

    2012-01-01

    By using best practices to manage unit and plant efficiency, hydro owner/operators can achieve significant improvements in overall plant performance, resulting in increased generation and profitability and, frequently, reduced maintenance costs. The Hydropower Advancement Project (HAP) was initiated by the Wind and Hydropower Technologies Program within the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy to develop and implement a systematic process with standard methodology, based on the best practices of operations, maintenance and upgrades; to identify the improvement opportunities at existing hydropower facilities; and to predict and trend the overall condition and improvement opportunity within the U.S. hydropower fleet. The HAP facility assessment includes both quantitative condition ratings and data-based performance analyses. However, this paper, as an overview document for the HAP, addresses the general concepts, project scope and objectives, best practices for unit and plant efficiency, and process and methodology for best practices implementation for hydropower efficiency and utilization improvement.

  2. ITW 1998,Killarney, Ireland. June 22 -26 Spectral Efficiency of Direct-Sequence Spread-Spectrum

    E-print Network

    Verdú, Sergio

    ITW 1998,Killarney, Ireland. June 22 - 26 Spectral Efficiency of Direct-Sequence Spread-Spectrum and d) minimum mean square error linear pro- cessing. I. CHANNELMODEL Coded direct-Sequence Spread-Spectrum incurred by the imposition of the direct-sequence spread-spectrum structure on the transmitted signals

  3. Energy and Throughput Efficient Strategies for Cooperative Spectrum Sensing in Cognitive Radios

    E-print Network

    Langendoen, Koen

    Energy and Throughput Efficient Strategies for Cooperative Spectrum Sensing in Cognitive Radios sensing based cognitive radio network employs a certain number of secondary users to sense the spectrum efficient setup, the number of cooperating cognitive radios is minimized for a k-out- of-N fusion rule

  4. Efficient utilization of graphics technology for space animation

    NASA Technical Reports Server (NTRS)

    Panos, Gregory Peter

    1989-01-01

    Efficient utilization of computer graphics technology has become a major investment in the work of aerospace engineers and mission designers. These new tools are having a significant impact in the development and analysis of complex tasks and procedures which must be prepared prior to actual space flight. Design and implementation of useful methods in applying these tools has evolved into a complex interaction of hardware, software, network, video and various user interfaces. Because few people can understand every aspect of this broad mix of technology, many specialists are required to build, train, maintain and adapt these tools to changing user needs. Researchers have set out to create systems where an engineering designer can easily work to achieve goals with a minimum of technological distraction. This was accomplished with high-performance flight simulation visual systems and supercomputer computational horsepower. Control throughout the creative process is judiciously applied while maintaining generality and ease of use to accommodate a wide variety of engineering needs.

  5. Fabrication Infrastructure to Enable Efficient Exploration and Utilization of Space

    NASA Technical Reports Server (NTRS)

    Howell, Joe T.; Fikes, John C.; McLemore, Carole A.; Manning, Curtis W.; Good, Jim

    2007-01-01

    Unlike past one-at-a-time mission approaches, system-of-systems infrastructures will be needed to enable ambitious scenarios for sustainable future space exploration and utilization. Fabrication infrastructure will be needed to support habitat structure development, tools and mechanical part fabrication, as well as repair and replacement of ground support and space mission hardware such as life support items, vehicle components and crew systems. The fabrication infrastructure will need the In Situ Fabrication and Repair (ISFR) element, which is working in conjunction with the In Situ Resources Utilization (ISRU) element, to live off the land. The ISFR Element supports the entire life cycle of Exploration by: reducing downtime due to failed components; decreasing risk to crew by recovering quickly from degraded operation of equipment; improving system functionality with advanced geometry capabilities; and enhancing mission safety by reducing assembly part counts of original designs where possible. This paper addresses the fabrication infrastructures that support efficient, affordable, reliable infrastructures for both space exploration systems and logistics; these infrastructures allow sustained, affordable and highly effective operations on the Moon, Mars and beyond.

  6. Efficient broadband-spectrum oscillation of ultrashort-pulse Kerr-lens mode-locked Yb:YAG laser with intracavity nonlinear media overcoming the fluorescence spectrum limit

    Microsoft Academic Search

    Shinichi MATSUBARA; Masaki TAKAMA; Masahiro INOUE; Hiroyuki HITOTSUYA; Shinya OKUDA; Mami ODAHARA; Sakae KAWATO; Yuzo ISHIDA

    2009-01-01

    Efficient broadband spectrum oscillation was obtained directly from a laser-diode-pumped Kerr-lens mode-locked Yb:YAG laser with intracavity nonlinear media. The spectrum was expanded to around 1040 nm to 1070 nm. The spectrum is much broader than the fluorescence spectrum at 1050 nm.

  7. Spectrum efficient A\\/J waveform for 21st century HF communications

    Microsoft Academic Search

    Paul K. Lee; Jeffrey A. Rudin

    1998-01-01

    The concept of spectrum efficient, anti-jam (A\\/J), high frequency (HF) communications is discussed. The HF concept is intended for mobile, beyond line of sight (BLOS) military communications for use in the 21st century. Spectrum efficiency and fast frequency hopping offer opportunities for high data rates and A\\/J capability. This system concept is referred to as HF 4 21. The concept

  8. Clinical utility of autism spectrum disorder scoring algorithms for the child symptom inventory-4.

    PubMed

    Gadow, Kenneth D; Schwartz, Joseph; Devincent, Carla; Strong, Greg; Cuva, Simone

    2008-03-01

    Few studies examine the clinical utility of autism spectrum disorder (ASD) rating scales for screening referrals to child psychiatry clinics. Parents/teachers from Long Island, NY, completed the Child Symptom Inventory-4, a DSM-IV-referenced rating scale for 6- to 12-year-old clinical referrals with an ASD (N = 317) or nonASD psychiatric (N = 191) diagnosis. Two separate groups of children attending public school, regular education classes in the same geographic area were also rated by their parents (N = 446) and teachers (N = 464). Stepwise forward regression generated a scoring algorithm based on a subset of all CSI-4 items that best differentiated ASD from nonASD children. ROC analyses indicated high levels of sensitivity/specificity for recommended ASD cutoff scores for parent and teacher ratings. PMID:17616796

  9. Energy efficient water utilization systems in process plants

    Microsoft Academic Search

    Miguel Bagajewicz; Hernán Rodera; Mariano Savelski

    2002-01-01

    This paper introduces a new approach for the design of water utilization networks featuring minimum freshwater usage and minimum utility consumption in process plants. The procedure is confined to treat the single pollutant case, and it is based on a linear programming formulation that relies on necessary conditions of optimality and a heat transshipment model. An LP model is first

  10. Optimization of gas utilization efficiency for short-pulsed electron cyclotron resonance ion source

    SciTech Connect

    Izotov, I. V.; Skalyga, V. A.; Zorin, V. G. [Institute of Applied Physics of Russian Academy of Sciences, Nizhny Novgorod (Russian Federation)

    2012-02-15

    Numerical analysis of {sup 6}He atoms utilizing efficiency in the ion source with powerful gyrotron heating is performed in present work using zero-dimensional balanced model of ECR discharge in a magnetic trap. Two ways of creation of ion source with high gas utilization efficiency (up to 60%-90%) are suggested.

  11. Efficient power spectrum estimation for high resolution CMB maps

    SciTech Connect

    Das, Sudeep; Hajian, Amir; Spergel, David N. [Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States)

    2009-04-15

    Estimation of the angular power spectrum of the cosmic microwave background on a small patch of sky is usually plagued by serious spectral leakage, especially when the map has a hard edge. Even on a full-sky map, point source masks can alias power from large scales to small scales producing excess variance at high multipoles. We describe a new fast, simple, and local method for estimation of power spectra on small patches of the sky that minimizes spectral leakage and reduces the variance of the spectral estimate. For example, when compared with the standard uniform sampling approach on a 8 deg. x 8 deg. patch of the sky with 2% area masked due to point sources, our estimator halves the error bars at l=2000 and achieves a more than fourfold reduction in error bars at l=3500. Thus, a properly analyzed experiment will have error bars at l=3500 equivalent to those of an experiment analyzed with the now standard technique with {approx}16-25 times the integration time.

  12. Encouraging the Construction of Energy Efficient Homes - A Utility Perspective 

    E-print Network

    Kimmons, G. H.

    1985-01-01

    Historically an industry with a supply side orientation, electric utilities are becoming increasingly involved with the end usage, or demand side, of their product as a means of effectively managing their systems....

  13. Assessing global resource utilization efficiency in the industrial sector.

    PubMed

    Rosen, Marc A

    2013-09-01

    Designing efficient energy systems, which also meet economic, environmental and other objectives and constraints, is a significant challenge. In a world with finite natural resources and large energy demands, it is important to understand not just actual efficiencies, but also limits to efficiency, as the latter identify margins for efficiency improvement. Energy analysis alone is inadequate, e.g., it yields energy efficiencies that do not provide limits to efficiency. To obtain meaningful and useful efficiencies for energy systems, and to clarify losses, exergy analysis is a beneficial and useful tool. Here, the global industrial sector and industries within it are assessed by using energy and exergy methods. The objective is to improve the understanding of the efficiency of global resource use in the industrial sector and, with this information, to facilitate the development, prioritization and ultimate implementation of rational improvement options. Global energy and exergy flow diagrams for the industrial sector are developed and overall efficiencies for the global industrial sector evaluated as 51% based on energy and 30% based on exergy. Consequently, exergy analysis indicates a less efficient picture of energy use in the global industrial sector than does energy analysis. A larger margin for improvement exists from an exergy perspective, compared to the overly optimistic margin indicated by energy. PMID:23235273

  14. A spectrum etiquette protocol for efficient coordination of radio devices in unlicensed bands

    Microsoft Academic Search

    D. Raychaudhuri; Xiangpeng Jing

    2003-01-01

    This paper presents a spectrum etiquette protocol for efficient coordination of radio communication devices in unlicensed (e.g. 2.4 GHz ISM and 5 GHz U-NII) frequency bands. The proposed etiquette method enables spectrum coordination between multiple wireless devices using different radio technologies such as IEEE 802.11.x, 802.15.x, Bluetooth, Hiperlan, etc. The basic idea is to standardize a simple common protocol for

  15. Efficient Seed Utilization for Reseeding based Compression* Erik H. Volkerink1,2

    E-print Network

    Stanford University

    1 Efficient Seed Utilization for Reseeding based Compression* Erik H. Volkerink1,2 , Subhasish of the conventional reseeding architecture is the limited seed efficiency due to the variance in the number in a compression ratio of 33x (with a seed efficiency of 95%), whereas the conventional reseeding architecture

  16. Molecular Control of Sucrose Utilization in Escherichia coli W, an Efficient Sucrose-Utilizing Strain

    PubMed Central

    Sabri, Suriana; Nielsen, Lars K.

    2013-01-01

    Sucrose is an industrially important carbon source for microbial fermentation. Sucrose utilization in Escherichia coli, however, is poorly understood, and most industrial strains cannot utilize sucrose. The roles of the chromosomally encoded sucrose catabolism (csc) genes in E. coli W were examined by knockout and overexpression experiments. At low sucrose concentrations, the csc genes are repressed and cells cannot grow. Removal of either the repressor protein (cscR) or the fructokinase (cscK) gene facilitated derepression. Furthermore, combinatorial knockout of cscR and cscK conferred an improved growth rate on low sucrose. The invertase (cscA) and sucrose transporter (cscB) genes are essential for sucrose catabolism in E. coli W, demonstrating that no other genes can provide sucrose transport or inversion activities. However, cscK is not essential for sucrose utilization. Fructose is excreted into the medium by the cscK-knockout strain in the presence of high sucrose, whereas at low sucrose (when carbon availability is limiting), fructose is utilized by the cell. Overexpression of cscA, cscAK, or cscAB could complement the W?cscRKAB knockout mutant or confer growth on a K-12 strain which could not naturally utilize sucrose. However, phenotypic stability and relatively good growth rates were observed in the K-12 strain only when overexpressing cscAB, and full growth rate complementation in W?cscRKAB also required cscAB. Our understanding of sucrose utilization can be used to improve E. coli W and engineer sucrose utilization in strains which do not naturally utilize sucrose, allowing substitution of sucrose for other, less desirable carbon sources in industrial fermentations. PMID:23124236

  17. Assessment of Global Functioning in Adolescents with Autism Spectrum Disorders: Utility of the Developmental Disability-Child Global Assessment Scale

    ERIC Educational Resources Information Center

    White, Susan W.; Smith, Laura A.; Schry, Amie R.

    2014-01-01

    Assessment of global functioning is an important consideration in treatment outcome research; yet, there is little guidance on its evidence-based assessment for children with autism spectrum disorders. This study investigated the utility and validity of clinician-rated global functioning using the Developmental Disability-Child Global Assessment…

  18. Utilization and Expenditure of Hospital Admission in Patients with Autism Spectrum Disorder: National Health Insurance Claims Database Analysis

    ERIC Educational Resources Information Center

    Lin, Jin-Ding; Hung, Wen-Jiu; Lin, Lan-Ping; Lai, Chia-Im

    2011-01-01

    There were not many studies to provide information on health access and health utilization of people with autism spectrum disorders (ASD). The present study describes a general profile of hospital admission and the medical cost among people with ASD, and to analyze the determinants of medical cost. A retrospective study was employed to analyze…

  19. Efficiency of Energy Utilization by Lactating Alpine Goats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-six lactating Alpine does (50.5 ± 1.2 kg BW) were used to determine the effect of stage of lactation on energy utilization. Twelve does were assigned for measurement periods in early, mid-, and late lactation (28-35, 91-98, and 189 to 196 d of lactation). For six does of each group, after m...

  20. Elastic reservations for efficient bandwidth utilization in LambdaGrids

    Microsoft Academic Search

    Sumit Naiksatam; Silvia M. Figueira

    2007-01-01

    We introduce the concept of elastic reservation of bandwidth capacity to mitigate the problem of bandwidth fragmentation in LambdaGrids and present a network model which can support elastic reservations. We also define the Elastic Scheduling Problem (ESP), which succinctly captures the optimal utilization objective of elastic reservations. Analysis of ESP reveals that it is an NP-complete problem. Hence we present

  1. Financial Analysis of Incentive Mechanisms to Promote Energy Efficiency: Case Study of a Prototypical Southwest Utility

    SciTech Connect

    Cappers, Peter; Goldman, Charles; Chait, Michele; Edgar, George; Schlegel, Jeff; Shirley, Wayne

    2009-03-04

    Many state regulatory commissions and policymakers want utilities to aggressively pursue energy efficiency as a strategy to mitigate demand and energy growth, diversify the resource mix, and provide an alternative to building new, costly generation. However, as the National Action Plan for Energy Efficiency (NAPEE 2007) points out, many utilities continue to shy away from aggressively expanding their energy efficiency efforts when their shareholder's fundamental financial interests are placed at risk by doing so. Thus, there is increased interest in developing effective ratemaking and policy approaches that address utility disincentives to pursue energy efficiency or lack of incentives for more aggressive energy efficiency efforts. New regulatory initiatives to promote increased utility energy efficiency efforts also affect the interests of consumers. Ratepayers and their advocates are concerned with issues of fairness, impacts on rates, and total consumer costs. From the perspective of energy efficiency advocates, the quid pro quo for utility shareholder incentives is the obligation to acquire all, or nearly all, achievable cost-effective energy efficiency. A key issue for state regulators and policymakers is how to maximize the cost-effective energy efficiency savings attained while achieving an equitable sharing of benefits, costs and risks among the various stakeholders. In this study, we modeled a prototypical vertically-integrated electric investor-owned utility in the southwestern US that is considering implementing several energy efficiency portfolios. We analyze the impact of these energy efficiency portfolios on utility shareholders and ratepayers as well as the incremental effect on each party when lost fixed cost recovery and/or utility shareholder incentive mechanisms are implemented. A primary goal of our quantitative modeling is to provide regulators and policymakers with an analytic framework and tools that assess the financial impacts of alternative incentive approaches on utility shareholders and customers if energy efficiency is implemented under various utility operating, cost, and supply conditions.We used and adapted a spreadsheet-based financial model (the Benefits Calculator) which was developed originally as a tool to support the National Action Plan for Energy Efficiency (NAPEE). The major steps in our analysis are displayed graphically in Figure ES- 1. Two main inputs are required: (1) characterization of the utility which includes its initial financial and physical market position, a forecast of the utility?s future sales, peak demand, and resource strategy to meet projected growth; and (2) characterization of the Demand-Side Resource (DSR) portfolio ? projected electricity and demand savings, costs and economic lifetime of a portfolio of energy efficiency (and/or demand response) programs that the utility is planning or considering implementing during the analysis period. The Benefits Calculator also estimates total resource costs and benefits of the DSR portfolio using a forecast of avoided capacity and energy costs. The Benefits Calculator then uses inputs provided in the Utility Characterization to produce a ?business-as usual? base case as well as alternative scenarios that include energy efficiency resources, including the corresponding utility financial budgets required in each case. If a decoupling and/or a shareholder incentive mechanism are instituted, the Benefits Calculator model readjusts the utility?s revenue requirement and retail rates accordingly. Finally, for each scenario, the Benefits Calculator produces several metrics that provides insights on how energy efficiency resources, decoupling and/or a shareholder incentive mechanism impacts utility shareholders (e.g. overall earnings, return on equity), ratepayers (e.g., average customer bills and rates) and society (e.g. net resource benefits).

  2. Efficient Energy Utilization in the Industrial Sector - Case Studies

    E-print Network

    Davis, S. R.

    1984-01-01

    from the steam generated, and 3rd -- Steam should be produced at the highest practical boiler efficiency. Typical results of a steam system will indicate a high percentage of steam traps inoperative, large steam leaks and low condensate return...

  3. Diffractive optical elements utilized for efficiency enhancement of photovoltaic modules.

    PubMed

    Mingareev, I; Berlich, R; Eichelkraut, T J; Herfurth, H; Heinemann, S; Richardson, M C

    2011-06-01

    Common solar cells used in photovoltaic modules feature metallic contacts which partially block the sunlight from reaching the semiconductor layer and reduce the overall efficiency of the modules. Diffractive optical elements were generated in the bulk glass of a photovoltaic module by ultrafast laser irradiation to direct light away from the contacts. Calculations of the planar electromagnetic wave diffraction and propagation were performed using the rigorous coupled wave analysis technique providing quantitative estimations for the potential efficiency enhancement of photovoltaic modules. PMID:21716370

  4. Energy utilization and efficiency analysis for hydrogen fuel cell vehicles

    Microsoft Academic Search

    R. M. Moore; K. H. Hauer; S. Ramaswamy; J. M. Cunningham

    2006-01-01

    This paper presents the results of an energy analysis for load-following versus battery-hybrid direct-hydrogen fuel cell vehicles. The analysis utilizes dynamic fuel cell vehicle simulation tools previously presented [R.M. Moore, K.H. Hauer, J. Cunningham, S. Ramaswamy, A dynamic simulation tool for the battery-hybrid hydrogen fuel cell vehicle, Fuel Cells, submitted for publication; R.M. Moore, K.H. Hauer, D.J. Friedman, J.M. Cunningham,

  5. Highly Efficient Photon Coupling Devices Utilizing a Nanofiber Tip

    NASA Astrophysics Data System (ADS)

    Chonan, Sho; Kato, Shinya; Aoki, Takao

    We have performed numerical simulations of photon coupling devices utilizing a nanofiber tip. It is shown that proposed devices can couple up to 38% of light from a point dipole source to the fundamental guided mode of a single-mode optical fiber. These devices can be applied for various kinds of single-photon emitter, including quantum dots, neutral atoms, and defect centers in diamond crystals.

  6. A High Efficiency Indirect Matrix Converter Utilizing RB-IGBTs

    Microsoft Academic Search

    T. Friedli; M. L. Heldwein; F. Giezendanner; J. W. Kolar

    2006-01-01

    This paper presents the design and construction of an indirect matrix converter (IMC) utilizing newly available IGBTs with reverse voltage blocking capability (RB-IGBTs). The design process involves the characterization of the RB-IGBTs by measuring the on-state parameters and the switching behavior in the rectifier stage of an IMC topology. Based on analytical equations the semiconductor losses are calculated and are

  7. The efficient discrete Tchebichef transform for spectrum analysis of speech recognition

    NASA Astrophysics Data System (ADS)

    Ernawan, Ferda; Abu, Nur A.; Suryana, Nanna

    2013-03-01

    Spectrum analysis is an elementary operation in speech recognition. Fast Fourier Transform (FFT) is a famous technique to analyze frequency spectrum of the signal in speech recognition. The Discrete Tchebichef Transform (DTT) is proposed as possible alternative to the FFT. DTT has lower computational complexity and it does not require complex transform with imaginary numbers. This paper proposes an approach based on 256 discrete orthonormal Tchebichef polynomials for efficient to analyze a vowel and a consonant in spectral frequency of speech recognition. The comparison between 1024 discrete Tchebichef transform and 256 discrete Tchebichef transform has been done. The preliminary experimental results show that 256 DTT has the potential to be efficient to transform time domain into frequency domain for speech recognition. 256 DTT produces simpler output than 1024 DTT in frequency spectrum. The used of 256 Discrete Tchebichef Transform can produce concurrently four formants F1, F2, F3 and F4 for the consonant.

  8. Efficiency of Lexical Access in Children with Autism Spectrum Disorders: Does Modality Matter?

    ERIC Educational Resources Information Center

    Harper-Hill, Keely; Copland, David; Arnott, Wendy

    2014-01-01

    The provision of visual support to individuals with an autism spectrum disorder (ASD) is widely recommended. We explored one mechanism underlying the use of visual supports: efficiency of language processing. Two groups of children, one with and one without an ASD, participated. The groups had comparable oral and written language skills and…

  9. Lateral Spectrum Splitting Concentrator Photovoltaics: Direct Measurement of Component and Submodule Efficiency

    SciTech Connect

    Xiaoting, W.; Waite, N.; Murcia, P.; Emery, K.; Steiner, M.; Kiamilev, F.; Goossen, K.; Honsberg, C.; Barnett, A.

    2012-03-01

    To achieve high energy conversion efficiency, a solar module architecture called lateral spectrum splitting concentrator photovoltaics (LSSCPV) is being developed. LSSCPV can concentrate available sunlight and laterally split a single beam into bands with different spectra for absorption by different solar cells with band gaps matched to the split spectrum. Test assemblies of a sample LSSCPV architecture were constructed, each of which contains four p-n junctions and two optical pieces. Independent experiments or simulations had been implemented on the components but by using optimal assumptions. In order to examine the actual performances of all the components, which are dependent on each other and the light source, direct outdoor measurements were made. A set of self-consistent efficiency definitions was articulated and a test bed was developed to measure the parameters required by the efficiency calculation. By comparing the component efficiency items derived from the outdoor measurement and the expected values based on independent simulations, the potential opportunities for efficiency improvement are determined. In the outdoor measurement at the University of Delaware, the optical component demonstrated 89.1% efficiency. Additional assemblies were tested at the National Renewable Energy Laboratory. One assembly demonstrated 36.7% submodule efficiency, which compares favorably with the 32.6% previously reported verified submodule efficiency.

  10. Computers and Chemical Engineering 26 (2002) 5979 Energy efficient water utilization systems in process plants

    E-print Network

    Savelski, Mariano J.

    2002-01-01

    Computers and Chemical Engineering 26 (2002) 59­79 Energy efficient water utilization systems. Once the energy and water targets have been identified, an MILP model is generated. This model, which. Keywords: Water utilization networks; Process plants; Energy minimization; Wastewater minimization

  11. Family-focused autism spectrum disorder research: a review of the utility of family systems approaches.

    PubMed

    Cridland, Elizabeth K; Jones, Sandra C; Magee, Christopher A; Caputi, Peter

    2014-04-01

    A family member with an autism spectrum disorder presents pervasive and bidirectional influences on the entire family system, suggesting a need for family-focused autism spectrum disorder research. While there has been increasing interest in this research area, family-focused autism spectrum disorder research can still be considered relatively recent, and there are limitations to the existing literature. The purpose of this article is to provide theoretical and methodological directions for future family-focused autism spectrum disorder research. In particular, this article proposes Family Systems approaches as a common theoretical framework for future family-focused autism spectrum disorder research by considering theoretical concepts such as Boundaries, Ambiguous Loss, Resilience and Traumatic Growth. We discuss reasons why these concepts are important to researching families living with autism spectrum disorder and provide recommendations for future research. The potential for research grounded in Family Systems approaches to influence clinical support services is also discussed. PMID:24092840

  12. MECHANISMS OF PLANT ZINC EFFICIENCY: THE CONTRIBUTION OF BIOCHEMICAL ZINC UTILIZATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zinc (Zn) deficiency is widespread in numerous crops and results in significant yield losses around the world. Application of Zn fertilizers is not an economically viable solution for this problem; therefore more efficient utilization in zinc efficient genotypes may be a more reasonable solution. Th...

  13. Utility Function Programs and Optimization over the Efficient Set in Multiple-Objective Decision Making

    Microsoft Academic Search

    R. Horst; N. V. Thoai

    1997-01-01

    Natural basic concepts in multiple-objective optimization lead to difficult multiextremal global optimization problems. Examples include detection of efficient points when nonconvexities occur, and optimization of a linear function over the efficient set in the convex (even linear) case. Assuming that a utility function exists allows one to replace in general the multiple-objective program by a single, nonconvex optimization problem, which

  14. Interactions between Energy Efficiency Programs funded under the Recovery Act and Utility Customer-Funded Energy Efficiency Programs

    SciTech Connect

    Goldman, Charles A.; Stuart, Elizabeth; Hoffman, Ian; Fuller, Merrian C.; Billingsley, Megan A.

    2011-02-25

    Since the spring of 2009, billions of federal dollars have been allocated to state and local governments as grants for energy efficiency and renewable energy projects and programs. The scale of this American Reinvestment and Recovery Act (ARRA) funding, focused on 'shovel-ready' projects to create and retain jobs, is unprecedented. Thousands of newly funded players - cities, counties, states, and tribes - and thousands of programs and projects are entering the existing landscape of energy efficiency programs for the first time or expanding their reach. The nation's experience base with energy efficiency is growing enormously, fed by federal dollars and driven by broader objectives than saving energy alone. State and local officials made countless choices in developing portfolios of ARRA-funded energy efficiency programs and deciding how their programs would relate to existing efficiency programs funded by utility customers. Those choices are worth examining as bellwethers of a future world where there may be multiple program administrators and funding sources in many states. What are the opportunities and challenges of this new environment? What short- and long-term impacts will this large, infusion of funds have on utility customer-funded programs; for example, on infrastructure for delivering energy efficiency services or on customer willingness to invest in energy efficiency? To what extent has the attribution of energy savings been a critical issue, especially where administrators of utility customer-funded energy efficiency programs have performance or shareholder incentives? Do the new ARRA-funded energy efficiency programs provide insights on roles or activities that are particularly well-suited to state and local program administrators vs. administrators or implementers of utility customer-funded programs? The answers could have important implications for the future of U.S. energy efficiency. This report focuses on a selected set of ARRA-funded energy efficiency programs administered by state energy offices: the State Energy Program (SEP) formula grants, the portion of Energy Efficiency and Conservation Block Grant (EECBG) formula funds administered directly by states, and the State Energy Efficient Appliance Rebate Program (SEEARP). Since these ARRA programs devote significant monies to energy efficiency and serve similar markets as utility customer-funded programs, there are frequent interactions between programs. We exclude the DOE low-income weatherization program and EECBG funding awarded directly to the over 2,200 cities, counties and tribes from our study to keep its scope manageable. We summarize the energy efficiency program design and funding choices made by the 50 state energy offices, 5 territories and the District of Columbia. We then focus on the specific choices made in 12 case study states. These states were selected based on the level of utility customer program funding, diversity of program administrator models, and geographic diversity. Based on interviews with more than 80 energy efficiency actors in those 12 states, we draw observations about states strategies for use of Recovery Act funds. We examine interactions between ARRA programs and utility customer-funded energy efficiency programs in terms of program planning, program design and implementation, policy issues, and potential long-term impacts. We consider how the existing regulatory policy framework and energy efficiency programs in these 12 states may have impacted development of these selected ARRA programs. Finally, we summarize key trends and highlight issues that evaluators of these ARRA programs may want to examine in more depth in their process and impact evaluations.

  15. Spread spectrum goes commercial

    Microsoft Academic Search

    D. L. Schilling; R. L. Pickholtz; L. B. Milstein

    1990-01-01

    The use of spread-spectrum techniques to achieve more efficient utilization of available frequency spectra is examined. The two main spread-spectrum techniques, direct sequence and frequency hopping, are explained. In frequency hopping, the transmitter repeatedly changes (hops) the carrier frequency from one frequency to another. Direct-sequence transmission spreads the spectrum not by periodically changing the frequency but by modulating the original

  16. Air Conditioner Efficiency Under Hot Dry and Hot Humid Conditions - The Utility Perspective 

    E-print Network

    Amarnath, A.

    2008-01-01

    have had their energy efficiency rated as with a seasonal yardstick, called Seasonal Energy Efficiency Ratio (SEER). As part of the set of laboratory tests and computer simulations required to calculate SEER, air conditioners are run at 82oF and 95o...-conditioning, Heating and Refrigeration Institute (AHRI). Laboratory and field research supported by utilities and energy efficiency agencies has found that SEER needs further improvement so that it can meet the new demands. Changes in SEER laboratory testing...

  17. An Efficient Moving Target Detection Algorithm Based on Sparsity-Aware Spectrum Estimation

    PubMed Central

    Shen, Mingwei; Wang, Jie; Wu, Di; Zhu, Daiyin

    2014-01-01

    In this paper, an efficient direct data domain space-time adaptive processing (STAP) algorithm for moving targets detection is proposed, which is achieved based on the distinct spectrum features of clutter and target signals in the angle-Doppler domain. To reduce the computational complexity, the high-resolution angle-Doppler spectrum is obtained by finding the sparsest coefficients in the angle domain using the reduced-dimension data within each Doppler bin. Moreover, we will then present a knowledge-aided block-size detection algorithm that can discriminate between the moving targets and the clutter based on the extracted spectrum features. The feasibility and effectiveness of the proposed method are validated through both numerical simulations and raw data processing results. PMID:25222035

  18. Shock Acceleration with Focused Transport Equation: Power-Law Energy Spectrum and Injection Efficiency

    NASA Astrophysics Data System (ADS)

    Zuo, P.; Zhang, M.; Gamayunov, K.; Luo, X.; Rassoul, H. K.

    2011-12-01

    The focused transport equation (FTE) includes all the necessary physics for modeling the shock acceleration of energetic particles with a unified description of first-order Fermi acceleration, shock drift acceleration, and shock surfing acceleration. In recent years, the FTE-based theory has been proved to be an efficient tool for reproducing the observational features of the lower energy Termination Shock Particles (TSPs) by Voyagers (e. g. le Roux et al. 2007; Florinski 2009). In this study we investigate the energy spectrum of pickup ions accelerated at shocks of various obliquities with FTE by using a stochastic approach model. Here we focus our discussion on how the focused transport acceleration using FTE is transformed to diffusive shock acceleration. The shock acceleration leads to two-component energy spectra. The low-energy component of the spectrum is made of particles that interact with shock one to a few times. For a parallel shock, the high energy component of the spectrum of power law with the spectral index being the same as the prediction of DSA theory, starts just a few times injection speed. For an oblique or quasi-perpendicular shock, the high-energy component of the spectrum exhibits a double power-law distribution: a harder power-law spectrum followed by another power-law spectrum with a slope the same as the spectral index of DSA. It can be concluded that the shock acceleration will eventually go into the DSA regime at higher energies even if the particle anisotropy is not small. The intensity of the energy spectrum given by the FTE, in the high-energy range where particles get efficient acceleration in the DSA regime, is different from that given by the standard DSA theory for the same injection source. We define the injection efficiency ? as the ratio between the two theoretical intensities. One of the advantages of the focused transport theory is that it allows calculation of the injection efficiency problem, something that is not easy to solve using other popular shock acceleration theories. In addition, our simulation is able to qualitatively explain the production of multiple power-law energy spectra of TSPs observed by Voyagers.

  19. Spectrally Efficient Spread Spectrum System Design: Message-Driven Frequency Hopping

    Microsoft Academic Search

    Qi Ling; Jian Ren; Tongtong Li

    2008-01-01

    Originally developed for secure communications in military applications, frequency hopping systems possess anti-jamming and anti-interception features by exploiting time- frequency diversity over large spectrum. However, the spectral efficiency of existing FH systems is very low due to inappropriate use of the total available bandwidth. To improve the system capacity, in this paper, we propose an innovative message-driven frequency hopping (MDFH)

  20. Spectral efficiency of direct-sequence spread-spectrum multiaccess with random spreading

    Microsoft Academic Search

    S. Verdu; Shlomo Shamai

    1998-01-01

    Information theoretic aspects of code division multiple access (CDMA) random direct-sequence spread-spectrum (DSSS) are investigated. The CDMA-DSSS channel with randomly and independently chosen spreading sequences accurately models the situation where pseudo-noise sequences span many symbol periods. We analyze the spectral efficiency (total capacity per chip) as a function of the number of users, spreading gain and signal-to-noise ratio, and we

  1. Identifying Cost-Effective Residential Energy Efficiency Opportunities for the Kauai Island Utility Cooperative

    SciTech Connect

    Busche, S.; Hockett, S.

    2010-06-01

    This analysis is an update to the 2005 Energy Efficiency Potential Study completed by KEMA for the Kauai Island Utility Cooperative (KIUC) and identifies potential energy efficiency opportunities in the residential sector on Kauai (KEMA 2005). The Total Resource Cost (TRC) test is used to determine which of the energy efficiency measures analyzed in the KEMA report are cost effective for KIUC to include in a residential energy efficiency program. This report finds that there remains potential energy efficiency savings that could be cost-effectively incentivized through a utility residential demand-side management program on Kauai if implemented in such a way that the program costs per measure are consistent with the current residential program costs.

  2. Engineering Pseudomonas putida S12 for Efficient Utilization of d-Xylose and l-Arabinose?

    PubMed Central

    Meijnen, Jean-Paul; de Winde, Johannes H.; Ruijssenaars, Harald J.

    2008-01-01

    The solvent-tolerant bacterium Pseudomonas putida S12 was engineered to utilize xylose as a substrate by expressing xylose isomerase (XylA) and xylulokinase (XylB) from Escherichia coli. The initial yield on xylose was low (9% [g CDW g substrate?1], where CDW is cell dry weight), and the growth rate was poor (0.01 h?1). The main cause of the low yield was the oxidation of xylose into the dead-end product xylonate by endogenous glucose dehydrogenase (Gcd). Subjecting the XylAB-expressing P. putida S12 to laboratory evolution yielded a strain that efficiently utilized xylose (yield, 52% [g CDW g xylose?1]) at a considerably improved growth rate (0.35 h?1). The high yield could be attributed in part to Gcd inactivity, whereas the improved growth rate may be connected to alterations in the primary metabolism. Surprisingly, without any further engineering, the evolved d-xylose-utilizing strain metabolized l-arabinose as efficiently as d-xylose. Furthermore, despite the loss of Gcd activity, the ability to utilize glucose was not affected. Thus, a P. putida S12-derived strain was obtained that efficiently utilizes the three main sugars present in lignocellulosic hydrolysate: glucose, xylose, and arabinose. This strain will form the basis for a platform host for the efficient production of biochemicals from renewable feedstock. PMID:18586973

  3. Engineering Pseudomonas putida S12 for efficient utilization of D-xylose and L-arabinose.

    PubMed

    Meijnen, Jean-Paul; de Winde, Johannes H; Ruijssenaars, Harald J

    2008-08-01

    The solvent-tolerant bacterium Pseudomonas putida S12 was engineered to utilize xylose as a substrate by expressing xylose isomerase (XylA) and xylulokinase (XylB) from Escherichia coli. The initial yield on xylose was low (9% [g CDW g substrate(-1)], where CDW is cell dry weight), and the growth rate was poor (0.01 h(-1)). The main cause of the low yield was the oxidation of xylose into the dead-end product xylonate by endogenous glucose dehydrogenase (Gcd). Subjecting the XylAB-expressing P. putida S12 to laboratory evolution yielded a strain that efficiently utilized xylose (yield, 52% [g CDW g xylose(-1)]) at a considerably improved growth rate (0.35 h(-1)). The high yield could be attributed in part to Gcd inactivity, whereas the improved growth rate may be connected to alterations in the primary metabolism. Surprisingly, without any further engineering, the evolved D-xylose-utilizing strain metabolized l-arabinose as efficiently as D-xylose. Furthermore, despite the loss of Gcd activity, the ability to utilize glucose was not affected. Thus, a P. putida S12-derived strain was obtained that efficiently utilizes the three main sugars present in lignocellulosic hydrolysate: glucose, xylose, and arabinose. This strain will form the basis for a platform host for the efficient production of biochemicals from renewable feedstock. PMID:18586973

  4. A 1MHz Area-Efficient On-Chip Spectrum Analyzer for Analog Testing

    Microsoft Academic Search

    Miguel Angel Domínguez; José L. Ausín; J. Francisco Duque-carrillo; Guido Torelli

    2006-01-01

    This paper presents a 0.35-?m CMOS on-chip spectrum analyzer based on switched-capacitor (SC) techniques. The prototype device\\u000a utilizes a 3-V supply and basically includes an SC sine-wave generator, a fourth-order high-selectivity SC filter, and a programmable\\u000a gain amplifier followed by an 8-b analog-to-digital converter. A non-uniform sampling scheme, which adds one degree of freedom\\u000a in determining the frequency response parameters

  5. Efficient Utilization of Scratch-Pad Memory in Embedded Processor Applications

    Microsoft Academic Search

    Preeti Ranjan Panda; Nikil D. Dutt; Alexandru Nicolau

    1997-01-01

    Efficient utilization of on-chip memory space is extremely important in modern embedded system applications based on microprocessor cores. In addition to a data cache that interfaces with slower off-chip memory, a fast on-chip SRAM, called Scratch-Pad memory, is often used in several applications. We present a technique for efficiently exploiting on-chip Scratch-Pad memory by partitioning the application's scalar and array

  6. Clinical utility of the selective serotonin reuptake inhibitors in the spectrum of anxiety

    Microsoft Academic Search

    Justine M Kent; Jeremy D Coplan; Jack M Gorman

    1998-01-01

    The selective serotonin reuptake inhibitors (SSRIs) are now being employed in the treatment of the full spectrum of anxiety disorders. In comparative trials, the SSRIs are proving to be equal or superior in efficacy to traditional antianxiety medications. Due to their favorable side effect profile, safety, and tolerability, they are rapidly replacing older agents in the treatment of anxiety. Neuroanatomical

  7. Utility of Formal Preference Assessments for Individuals Diagnosed with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Leaf, Justin B.; Leaf, Ronald; Alcalay, Aditt; Leaf, Jeremy A.; Ravid, Daniel; Dale, Stephanie; Kassardjian, Alyne; Tsuji, Kathleen; Taubman, Mitchell; McEachin, John; Oppenheim-Leaf, Misty

    2015-01-01

    The systematic use of reinforcers is an essential component of behavioral intervention for individuals diagnosed with Autism Spectrum Disorder. Today, the use of rigorous formal preference assessments, including paired-preference assessments, are widely conducted to help determine which items to use as reinforcers during intervention. Although…

  8. UTILITY OF A WIDE SPECTRUM LIGHT METER AS AN UNDERWATER SENSOR OF PHOTOSYNTHETICALLY ACTIVE RADIATION (PAR)

    EPA Science Inventory

    The strong attenuation of infra red wavelengths (>700 nm) in coastal waters is suggestive that some instruments with broad spectral responses might be useful, inexpensive substitutes for PAR sensors in studies of estuarine plant dynamics. Wide spectrum (350-1100 nm) light intensi...

  9. Nitrogen utilization efficiency: Relationships with grain yield, grain protein, and yield-related traits in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice (Oryza sativa L.) breeders have historically not included nitrogen utilization efficiency (NUE) as a selection criterion in breeding for cultivars, even though it has economic and ecological implications. This study examined the significance and magnitude of variation in N content, NUE, N trans...

  10. Evaluation of energy efficiency of various biogas production and utilization pathways

    Microsoft Academic Search

    Martina Pöschl; Shane Ward; Philip Owende

    2010-01-01

    The energy efficiency of different biogas systems, including single and co-digestion of multiple feedstock, different biogas utilization pathways, and waste-stream management strategies was evaluated. The input data were derived from assessment of existing biogas systems, present knowledge on anaerobic digestion process management and technologies for biogas system operating conditions in Germany. The energy balance was evaluated as Primary Energy Input

  11. Efficient Support of Video Streaming to Mobile Devices with Utilization of Multiple Radio Interfaces

    E-print Network

    Langendoen, Koen

    Efficient Support of Video Streaming to Mobile Devices with Utilization of Multiple Radio;#12;#12;Abstract An annoying experience in streaming multimedia to the mobile user is a fluctuating me- dia quality due to the varying characteristics of the wireless link. This thesis aims to improve the mobile user

  12. Adapting wave-front algorithms to efficiently utilize systems with deep communication hierarchies

    E-print Network

    Pakin, Scott

    Adapting wave-front algorithms to efficiently utilize systems with deep communication hierarchies Northwest National Laboratory, WA 99353, USA b Computer, Computational, and Statistical Sciences, Los Alamos National Laboratory, NM 87544, USA a r t i c l e i n f o Article history: Available online 3 March 2011

  13. A high-efficiency indirect lighting system utilizing the solar 1000 sulfur lamp

    SciTech Connect

    Siminovitch, M.; Gould, C.; Page, E.

    1997-06-01

    High-lumen light sources represent unique challenges and opportunities for the design of practical and efficient interior lighting systems. High-output sources require a means of large-scale distribution and avoidance of high-luminance glare while providing efficient delivery. An indirect lighting system has been developed for use with a 1,000 Watt sulfur lamp that efficiently utilizes the high-output source to provide quality interior lighting. This paper briefly describes the design and initial testing of this new system.

  14. Utilization of full spectrum space in single-sensor-based optical dynamic measurement

    Microsoft Academic Search

    Y. Fu; M. Guo; P. B. Phua

    2010-01-01

    In recent years, interferometry-based dynamic measurement has been widely used in industrial area for noncontact measurement of vibration or continuous deformation. In dynamic measurement, the traditional phase extraction method, phase shifting technique, is not easily accomplished with either high-speed camera or single-pixel photo detector. Hence spectrum analysis becomes a predominant method to extract transient phases. Due to the development of

  15. Effects of space flight, clinorotation, and centrifugation on the substrate utilization efficiency of E. coli

    NASA Technical Reports Server (NTRS)

    Brown, Robert B.; Klaus, D.; Todd, P.

    2002-01-01

    Cultures of Escherichia coli grown in space reached a 25% higher average final cell population than those in comparably matched ground controls (p<0.05). However, both groups consumed the same quantity of glucose, which suggests that space flight not only stimulated bacterial growth as has been previously reported, but also resulted in a 25% more efficient utilization of the available nutrients. Supporting experiments performed in "simulated weightlessness" under clinorotation produced similar trends of increased growth and efficiency, but to a lesser extent in absolute values. These experiments resulted in increases of 12% and 9% in average final cell population (p<0.05), while the efficiency of substrate utilization improved by 6% and 9% relative to static controls (p=0.12 and p<0.05, respectively). In contrast, hypergravity, produced by centrifugation, predictably resulted in the opposite effect--a decrease of 33% to 40% in final cell numbers with corresponding 29% to 40% lower net growth efficiencies (p<0.01). Collectively, these findings support the hypothesis that the increased bacterial growth observed in weightlessness is a result of reduced extracellular mass transport that occurs in the absence of sedimentation and buoyancy-driven convection, which consequently also improves substrate utilization efficiency in suspended cultures.

  16. HC-MAC: A Hardware-Constrained Cognitive MAC for Efficient Spectrum Management

    Microsoft Academic Search

    Juncheng Jia; Qian Zhang; Xuemin Shen

    2008-01-01

    Radio spectrum resource is of fundamental impor- tance for wireless communication. Recent reports show that most available spectrum has been allocated. While some of the spectrum bands (e.g., unlicensed band, GSM band) have seen increasingly crowded usage, most of the other spectrum resources are underutilized. This drives the emergence of open spectrum and dynamic spectrum access concepts, which allow unlicensed

  17. Spectrum Sensing: First Step Towards Cognitive Radio

    E-print Network

    Yu, Chansu

    the spectrum of available bandwidths, which will be the focus of this project. Background The author's interest Topic: Spectrum Sensing Project Goal As the key first step to efficient utilization of availableSpectrum Sensing: First Step Towards Cognitive Radio Seth Myers Mobile Computing EE 787 May 7, 2009

  18. A scoping study on energy-efficiency market transformation by California Utility DSM Programs

    SciTech Connect

    Eto, J.; Prahl, R.; Schlegel, J.

    1996-07-01

    Market transformation has emerged as a central policy objective for future publicly-funded energy-efficiency programs in California. California Public Utilities Commission (CPUC) Decision 95-12-063 calls for public funding to shift to activities designed to transform the energy-efficiency market. The CPUC envisions that funding {open_quotes}would only be needed for specific and limited periods of time to cause the market to be transformed{close_quotes}. At the same time, the CPUC also acknowledges that {open_quotes}there are many definitions of market transformation{close_quotes} ... and does {open_quotes}not attempt to refine those definitions today{close_quotes}. We argue that a definition of market transformation is essential. The literature is now replete with definitions, and an operational definition is needed for the CPUC to decide on which programs should be supported with public funds. The CPUC decision initially indicated a preference for programs that do not provide financial assistance 4-efficiency programs that rely on financial assistance to customers. However, energy customers have traditionally accounted for a substantial portion of California utility`s DSM programs, so the CPUC`s direction to use ratepayer funds to support programs that will transform the market raises critical questions about how to analyze what has happened in order to plan effectively for the future: Which utility energy-efficiency programs, including those that provide financial assistance to customers, have had market transforming effects? To what extent do current regulatory rules and practices encourage or discourage utilities from running programs that are designed to transform the market? Should the rules and programs be modified, and, if so, how, to promote market transformation?

  19. Price-Based Spectrum Management in Cognitive Radio Networks

    Microsoft Academic Search

    Fan Wang; Marwan Krunz; Shuguang Cui

    2008-01-01

    Cognitive radios (CRs) have a great potential to improve spectrum utilization by enabling users to access the spectrum dynamically without disturbing licensed primary radios (PRs). A key challenge in operating these radios as a network is how to implement an efficient medium access control (MAC) mechanism that can adaptively and efficiently allocate transmission powers and spectrum among CRs according to

  20. Efficiency of utilization of nitrogen coated with urease inhibitor in maize.

    PubMed

    Okumura, Ricardo S; Mariano, Daiane de C; Zaccheo, Paulo V C; de Albuquerque, Amanda N; Giebelmeier, Carmo G; da S Lobato, Allan K; Franco, Antônio A N; de Oliveira, Neto Cândido F; Saldanha, Eduardo C M; da Conceição, Heráclito E O; da Silva, Raimundo T L

    2013-09-01

    This study aimed to evaluate under field conditions the efficiency in the use ofN coated with urease inhibitor in maize. The experiment was conducted in the year of 2007/2008. The experimental design was a randomized block design in a factorial 2 x 6, with five repetitions, constituted the N sources (common and coated with urease inhibitor) and levels (0, 40, 80, 120, 160 and 200 kg ha-1 of N) sidedressing nitrogen application in the growth stage V4. Based on the data obtained were determined recovery efficiencies, utilization, agronomic and physiological N applied. In all cases, the efficiency levels for maize were influenced by levels of sidedressing nitrogen application, in which increasing levels of N resulted in a decrease of the efficiencies, regardless of the source being common urea or coated with urease inhibitor. PMID:24498841

  1. Effect of temperature on light utilization efficiency of leaves in C 3 legumes and C 4 grasses

    Microsoft Academic Search

    M. M. Ludlow

    1981-01-01

    The effect of temperatures between 15 and 50°C on the light utilization efficiency of leaf net photosynthesis was studied in two C4 grasses and two C3 legumes. In the legumes, light utilization efficiency (? mol of CO2 fixed per ? Einstein of incident photosynthetic quantum flux) declined linearly with temperature between 15 and 45°C. On the other hand, it was

  2. The total cost and measured performance of utility-sponsored energy efficiency programs

    SciTech Connect

    Eto, J.; Vine, E.; Shown, L. [Lawrence Berkeley National Laboratory, CA (United States)] [and others

    1996-06-01

    By examining the actual performance of conservation or demand-side management (DSM) programs for ten utilities, Joskow and Marron (1992) have made an important contribution to policy discussions about the wisdom of relying on utilities to improve customer energy efficiency. We use Joskow and Marron`s method to analyze twenty utility commercial lighting programs and, like Joskow and Marron, find wide variations in industry reporting practices and savings evaluation methods. We extend the method by systematically accounting for several of the most important sources of variation and comment on how they influence total program costs. Our accounting also allows us to relate remaining program cost variations to the program sizes and the electric supply costs avoided by the programs. We draw qualified, yet affirmative, conclusions regarding the cost effectiveness of the programs.

  3. A nonparametric elicitation of the equity-efficiency trade-off in cost-utility analysis.

    PubMed

    Bleichrodt, Han; Doctor, Jason; Stolk, Elly

    2005-07-01

    We performed an empirical elicitation of the equity-efficiency trade-off in cost-utility analysis using the rank-dependent quality-adjusted life-year (QALY) model, a model that includes as special cases many of the social welfare functions that have been proposed in the literature. Our elicitation method corrects for utility curvature and, therefore, our estimated equity weights are not affected by diminishing marginal utility. We observed a preference for equality in the allocation of health. The data suggest that the elicited equity weights were jointly determined by preferences for equality and by insensitivity to group size. A procedure is proposed to correct the equity weights for insensitivity to group size. Finally, we give an illustration how our method can be implemented in health policy. PMID:15960990

  4. A Study About Improvement of Efficiency of a Sewage Heat Utilization System

    NASA Astrophysics Data System (ADS)

    Kobayakawa, Tomoaki; Hihara, Eiji; Hanazaki, Hirotaka

    On the basis of the data analysis of operational performance at the DHC plant in Makuhari HB area, it is examined how the properties of the sewage used as a heat source affect the effectiveness of the system. The result of this study suggests that a sewage heat utilization system is able to perform higher efficiency when it is designed as a distributed system that has separate heat sources than a central system.

  5. Evaluation of phosphorus starvation inducible genes relating to efficient phosphorus utilization in rice

    Microsoft Academic Search

    T. Shinano; M. Nanamori; M. Dohi; J. Wasaki; M. Osaki

    2005-01-01

    Plants develop strategies to recycle phosphorus so that all organs receive adequate amounts of phosphorus, especially new\\u000a growing organs. To evaluate the metabolic adaptation of rice plants under phosphorus deficient conditions, we selected several\\u000a genes related to phosphorus utilization efficiency in the cell. Phosphoenolpyruvate carboxylase, triose phosphate translocator, phosphoenolpyruvate\\/phosphate translocator (PPT), pyruvate kinase, NAD dependent glyceraldehyde-3-phosphate dehydrogenase, and NADP dependent

  6. Potential nutrient supply, nutrient utilization efficiencies, fertilizer recovery rates and maize yield in northern Nigeria

    Microsoft Academic Search

    Fritz Oben Tabi; Jan Diels; Ayo O. Ogunkunle; Emmanuel N. O. Iwuafor; Bernard Vanlauwe; N. Sanginga

    2008-01-01

    Potential N (SN) and P (SP) supplies, N and P utilization efficiencies and fertilizer recovery rates for the northern Guinea\\u000a Savanna (NGS) agro-ecological zone of Nigeria were derived from data collected on farmers’ fields, and used as input in the\\u000a QUantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model. The potential N supply ranged from 7 to 56 kg N ha?1,

  7. Utilization of Magnetic Resonance Imaging in Research Involving Animal Models of Fetal Alcohol Spectrum Disorders

    PubMed Central

    Wang, Xiaojie; Kroenke, Christopher D.

    2015-01-01

    It is well recognized that fetal alcohol exposure can profoundly damage the developing brain. The term fetal alcohol spectrum disorder (FASD) describes the range of deficits that result from prenatal alcohol exposure. Over the past two decades, researchers have used magnetic resonance imaging (MRI) as a noninvasive technique to characterize anatomical, physiological, and metabolic changes in the human brain that are part of FASD. As using animal models can circumvent many of the complications inherent to human studies, researchers have established and explored a number of models involving a range of species. Using MRI-based modalities, the FASD animal models have demonstrated decreased brain volume and abnormal brain shape, disrupted cellular morphology differentiation, altered neurochemistry, and blood perfusion. These animal studies have facilitated characterization of the direct effects of ethanol; in many cases identifying specific sequelae related to the timing and dose of exposure. Further, as a result of the ability to perform traditional (such as histological) analyses on animal brains following neuroimaging experiments, this work leads to improvements in the accuracy of our interpretations of neuroimaging findings in human studies.

  8. Spectrum Orbit Utilization Program documentation: SOUP5 version 3.8 user's manual, volume 1, chapters 1 through 5

    NASA Technical Reports Server (NTRS)

    Davidson, J.; Ottey, H. R.; Sawitz, P.; Zusman, F. S.

    1985-01-01

    The underlying engineering and mathematical models as well as the computational methods used by the Spectrum Orbit Utilization Program 5 (SOUP5) analysis programs are described. Included are the algorithms used to calculate the technical parameters, and references to the technical literature. The organization, capabilities, processing sequences, and processing and data options of the SOUP5 system are described. The details of the geometric calculations are given. Also discussed are the various antenna gain algorithms; rain attenuation and depolarization calculations; calculations of transmitter power and received power flux density; channelization options, interference categories, and protection ratio calculation; generation of aggregrate interference and margins; equivalent gain calculations; and how to enter a protection ratio template.

  9. Fluorescence Efficiency and Visible Re-emission Spectrum of Tetraphenyl Butadiene Films at Extreme Ultraviolet Wavelengths

    E-print Network

    V. M. Gehman; S. R. Seibert; K. Rielage; A. Hime; Y. Sun; D. -M. Mei; J. Maassen; D. Moore

    2011-09-22

    A large number of current and future experiments in neutrino and dark matter detection use the scintillation light from noble elements as a mechanism for measuring energy deposition. The scintillation light from these elements is produced in the extreme ultraviolet (EUV) range, from 60 - 200 nm. Currently, the most practical technique for observing light at these wavelengths is to surround the scintillation volume with a thin film of Tetraphenyl Butadiene (TPB) to act as a fluor. The TPB film absorbs EUV photons and reemits visible photons, detectable with a variety of commercial photosensors. Here we present a measurement of the re-emission spectrum of TPB films when illuminated with 128, 160, 175, and 250 nm light. We also measure the fluorescence efficiency as a function of incident wavelength from 120 to 250 nm.

  10. Photoionization mass spectrometric study of HOCl: Photoionization efficiency spectrum and ionization energy

    SciTech Connect

    Thorn, R.P. Jr.; Stief, L.J. [NASA/Goddard Space Flight Center, Greenbelt, MD (United States). Lab. for Extraterrestrial Physics] [NASA/Goddard Space Flight Center, Greenbelt, MD (United States). Lab. for Extraterrestrial Physics; Kuo, S.C.; Klemm, R.B. [Brookhaven National Lab., Upton, NY (United States)] [Brookhaven National Lab., Upton, NY (United States)

    1999-02-18

    The photoionization efficiency (PIE) spectrum of HOCl was measured over the wavelength range {lambda} = 102--115 nm, using a discharge flow-photoionization mass spectrometer (DF-PIMS) apparatus coupled to a synchrotron radiation source. The PIE spectra displayed steplike behavior near threshold. This study represents the first determination of the HOCl photoionization efficiency spectrum and the photoionization threshold. A value of 11.12{sub 3} {+-} 0.01{sub 8} eV was obtained for the adiabatic ionization energy (IE) of HOCl from analysis of photoion thresholds, corresponding to the HOCl{sup +}(X{sup 2}A{double_prime}) {l_arrow} HOCl(X{sup 1}A{double_prime}) transition. The PIMS result is identical to the only previous experimental measurement and in good agreement with a recent ab initio calculation. From the result for IE(HOCl), a value of 999.4 {+-} 3.6 kJ mol{sup {minus}1} was calculated for {Delta}{sub f}H{degree}{sub 0}(HOCl{sup +}), and from the latter, the proton affinity of ClO at T = 0 K, PA{sub 0}(ClO), was determined to be 629.6 {+-} 3.6 kJ mol{sup {minus}1}. At 298 K, the computed values for {Delta}{sub f}H{degree}{sub 298}(HOCl{sup +}) and PA{sub 298}(ClO) are 996.5 {+-} 3.6 and 635.1 {+-} 3.6 kJ mol{sup {minus}1}, respectively.

  11. Optimal Design of site investigation: Entropy based Utility functions and efficient implementations

    NASA Astrophysics Data System (ADS)

    Geiges, A.; Nowak, W.

    2011-12-01

    Integrating additional data into (stochastic) hydro-geological models helps to improve prediction quality. For a given modeling task, Optimal Design (OD) of data acquisition is used to search for the most `valuable` set of data, thus providing guidance on how to approach site investigation. The utility of data can be quantified theoretically by Mutual Information (MI), which measures the information content of potential data sets for the prediction quantity of interest. OD requires to evaluate the chosen utility function for all potential design pattern averaged over all possible data values, which makes OD computationally extremely burdening. The computational costs mainly depend on (1) the number of possible designs, (2) the efficiency of the involved search algorithm for high-dimensional optimization, and (3) the precise choice and computational implementation of the utility function. Due to high-computational costs, utility functions are often only approximations of MI, including linearizations (e.g. posterior variances, covariances). In previous work it has been shown, that such linearized analyses lead to a dramatic speedup, however fail to discover non-linear dependencies between possible observations and predictions goals and therefore often lead to suboptimal results. The current study focuses on efficient choices and implementations of utility functions in OD. Growing and cheap computer power nowadays allows direct and more accurate evaluation of MI based on entropy estimates or non-linear Bayesian updating schemes. In particular, because MI is a symmetric information measure several different formulations are possible. The options developed in this study include forward evaluation, reverse evaluation and evaluation based on joint distributions. In addition, many approximation of MI are available, but their behavior and computational requirements are mostly unknown. To allow an informed decision, we compare different approximations and formulations of MI in terms of computational efficiency, accuracy, resulting design quality and feasibility for applications to large data sets. We developed an error estimate to asses accuracy versus efficiency. In addition, the options of linearization are pointed out and discussed for some possible approximations. Finally, we investigated in which cases the improvement of design quality may justify the additional computational costs for switching to more accurate yet slower formulations or implementations.

  12. RBFN Based Efficiency Optimization Method of Induction Motor Utilized in Electrically Driven Marine Propellers

    NASA Astrophysics Data System (ADS)

    Supari; Syafaruddin; Negara, I. Made Yulistya; Ashari, Mochamad; Hiyama, Takashi

    Thruster controllers of electric propulsion system with fixed pitch propellers are conventionally aimed to control only the shaft speed without utilizing the capabilities of the controllers to apply any other control strategies. In fact, the dynamic operating conditions lead to the fluctuation of motor load. For this reason, utilizing conventional controllers is hard enough due to the critical constraints and limitation of the ship power source. The paper presents study and analysis of efficiency optimization strategy in thruster shaft speed controllers driven by induction motor. The control strategy based on intelligent method called radial basis function neural network (RBFN) is implemented. A set of training data derived from a loss model controller of the induction motor working under indirect field-oriented-control (IFOC) drives is used for training process of RBFN. The loss model controller utilizes schematically the flux generating current as controlling variable. Estimation of the flux generating current through the RBFN process shows significant improvement in motor efficiency especially for low speed and ship transit system.

  13. Energy Efficiency as a Preferred Resource: Evidence from Utility Resource Plans in the Western United States and Canada

    SciTech Connect

    Hopper, Nichole; Barbose, Galen; Goldman, Charles; Schlegel, Jeff

    2008-09-15

    This article examines the future role of energy efficiency as a resource in the Western United States and Canada, as envisioned in the most recent resource plans issued by 16 utilities, representing about 60percent of the region's load. Utility and third-party administered energy efficiency programs proposed by 15 utilities over a ten-year horizon would save almost 19,000 GWh annually, about 5.2percent of forecast load. There are clear regional trends in the aggressiveness of proposed energy savings. California's investor-owned utilities (IOUs) had the most aggressive savings targets, followed by IOUs in the Pacific Northwest, and the lowest savings were proposed by utilities in Inland West states and by two public utilities on the West coast. The adoption of multiple, aggressive policies targeting energy efficiency and climate change appear to produce sizeable energy efficiency commitments. Certain specific policies, such as mandated energy savings goals for California's IOUs and energy efficiency provisions in Nevada's Renewable Portfolio Standard had a direct impact on the level of energy savings included in the resource plans. Other policies, such as revenue decoupling and shareholder incentives, and voluntary or legislatively mandated greenhouse gas emission reduction policies, may have also impacted utilities' energy efficiency commitments, though the effects of these policies are not easily measured. Despite progress among the utilities in our sample, more aggressive energy efficiency strategies that include high-efficiency standards for additional appliances and equipment, tighter building codes for new construction and renovation, as well as more comprehensive ratepayer-funded energy efficiency programs are likely to be necessary to achieve a region-wide goal of meeting 20percent of electricity demand with efficiency in 2020.

  14. Metabolic and Regulatory Rearrangements Underlying Efficient d-Xylose Utilization in Engineered Pseudomonas putida S12*

    PubMed Central

    Meijnen, Jean-Paul; de Winde, Johannes H.; Ruijssenaars, Harald J.

    2012-01-01

    Previously, an efficient d-xylose utilizing Pseudomonas putida S12 strain was obtained by introducing the d-xylose isomerase pathway from Escherichia coli, followed by evolutionary selection. In the present study, systemic changes associated with the evolved phenotype were identified by transcriptomics, enzyme activity analysis, and inverse engineering. A key element in improving the initially poor d-xylose utilization was the redistribution of 6-phospho-d-gluconate (6-PG) between the Entner-Doudoroff pathway and the oxidative pentose phosphate (PP) pathway. This redistribution increased the availability of 6-PG for oxidative decarboxylation to d-ribose-5-phosphate, which is essential for the utilization of d-xylose via the nonoxidative PP pathway. The metabolic redistribution of 6-PG was procured by modified HexR regulation, which in addition appeared to control periplasmic sugar oxidation. Because the absence of periplasmic d-xylonate formation was previously demonstrated to be essential for achieving a high biomass yield on d-xylose, the aberrant HexR control appeared to underlie both the improved growth rate and biomass yield of the evolved d-xylose utilizing P. putida strain. The increased oxidative PP pathway activity furthermore resulted in an elevated NADH/NAD+ ratio that caused the metabolic flux to be redirected from the TCA cycle to the glyoxylate shunt, which was also activated transcriptionally. Clearly, these findings may serve as an important case in point to engineer and improve the utilization of non-natural carbon sources in a wide range of industrial microorganisms. PMID:22416130

  15. Metabolic and regulatory rearrangements underlying efficient D-xylose utilization in engineered Pseudomonas putida S12.

    PubMed

    Meijnen, Jean-Paul; de Winde, Johannes H; Ruijssenaars, Harald J

    2012-04-27

    Previously, an efficient D-xylose utilizing Pseudomonas putida S12 strain was obtained by introducing the D-xylose isomerase pathway from Escherichia coli, followed by evolutionary selection. In the present study, systemic changes associated with the evolved phenotype were identified by transcriptomics, enzyme activity analysis, and inverse engineering. A key element in improving the initially poor D-xylose utilization was the redistribution of 6-phospho-D-gluconate (6-PG) between the Entner-Doudoroff pathway and the oxidative pentose phosphate (PP) pathway. This redistribution increased the availability of 6-PG for oxidative decarboxylation to D-ribose-5-phosphate, which is essential for the utilization of D-xylose via the nonoxidative PP pathway. The metabolic redistribution of 6-PG was procured by modified HexR regulation, which in addition appeared to control periplasmic sugar oxidation. Because the absence of periplasmic D-xylonate formation was previously demonstrated to be essential for achieving a high biomass yield on D-xylose, the aberrant HexR control appeared to underlie both the improved growth rate and biomass yield of the evolved D-xylose utilizing P. putida strain. The increased oxidative PP pathway activity furthermore resulted in an elevated NADH/NAD(+) ratio that caused the metabolic flux to be redirected from the TCA cycle to the glyoxylate shunt, which was also activated transcriptionally. Clearly, these findings may serve as an important case in point to engineer and improve the utilization of non-natural carbon sources in a wide range of industrial microorganisms. PMID:22416130

  16. Efficient Organic Photovoltaics Utilizing Nanoscale Heterojunctions in Sequentially Deposited Polymer/fullerene Bilayer

    PubMed Central

    Seok, Jeesoo; Shin, Tae Joo; Park, Sungmin; Cho, Changsoon; Lee, Jung-Yong; Yeol Ryu, Du; Kim, Myung Hwa; Kim, Kyungkon

    2015-01-01

    A highly efficient sequentially deposited bilayer (SD-bilayer) of polymer/fullerene organic photovoltaic (OPV) device is developed via the solution process. Herein, we resolve two essential problems regarding the construction of an efficient SD-bilayer OPV. First, the solution process fabrication of the SD-bilayer is resolved by incorporating an ordering agent (OA) to the polymer solution, which improves the ordering of the polymer chain and prevents the bottom-layer from dissolving into the top-layer solution. Second, a non-planar heterojunction with a large surface area is formed by the incorporation of a heterojunction agent (HA) to the top-layer solution. Poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT) is used for the bottom-layer and phenyl-C71-butyric-acid-methyl ester (PC70BM) is used for the top-layer. The SD-bilayer OPV produced utilizing both an OA and HA exhibits a power conversion efficiency (PCE) of 7.12% with a high internal quantum efficiency (IQE). We believe our bilayer system affords a new way of forming OPVs distinct from bulk heterojunction (BHJ) systems and offers a chance to reconsider the polymers that have thus far shown unsatisfactory performance in BHJ systems. PMID:25670623

  17. Efficient Organic Photovoltaics Utilizing Nanoscale Heterojunctions in Sequentially Deposited Polymer/fullerene Bilayer

    NASA Astrophysics Data System (ADS)

    Seok, Jeesoo; Shin, Tae Joo; Park, Sungmin; Cho, Changsoon; Lee, Jung-Yong; Yeol Ryu, Du; Kim, Myung Hwa; Kim, Kyungkon

    2015-02-01

    A highly efficient sequentially deposited bilayer (SD-bilayer) of polymer/fullerene organic photovoltaic (OPV) device is developed via the solution process. Herein, we resolve two essential problems regarding the construction of an efficient SD-bilayer OPV. First, the solution process fabrication of the SD-bilayer is resolved by incorporating an ordering agent (OA) to the polymer solution, which improves the ordering of the polymer chain and prevents the bottom-layer from dissolving into the top-layer solution. Second, a non-planar heterojunction with a large surface area is formed by the incorporation of a heterojunction agent (HA) to the top-layer solution. Poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT) is used for the bottom-layer and phenyl-C71-butyric-acid-methyl ester (PC70BM) is used for the top-layer. The SD-bilayer OPV produced utilizing both an OA and HA exhibits a power conversion efficiency (PCE) of 7.12% with a high internal quantum efficiency (IQE). We believe our bilayer system affords a new way of forming OPVs distinct from bulk heterojunction (BHJ) systems and offers a chance to reconsider the polymers that have thus far shown unsatisfactory performance in BHJ systems.

  18. Resonant-cavity-enhanced p-i-n photodiode with a broad quantum-efficiency spectrum by use of

    E-print Network

    Fainman, Yeshaiahu

    Resonant-cavity-enhanced p-i-n photodiode with a broad quantum-efficiency spectrum by use of an anomalous-dispersion mirror Chyong-Hua Chen, Kevin Tetz, and Yeshaiahu Fainman A resonant because of anomalous dispersion of the reflection phase of a mirror in the device and describe conditions

  19. An Approach to Integrated Spectrum Efficient Network Enhanced Telemetry (iSENET))

    NASA Technical Reports Server (NTRS)

    Okino, Clayton; Gao, Jay; Clare, Loren; Darden, Scott; Walsh, William; Loh, Kok-kiong

    2006-01-01

    As the integrated Network Enhanced Telemetry (iNET) program moves forward in resolving systems engineering design and architecture definition, critical technology "gaps" and a migration path to realizing the integration of this technology are needed to insure a smooth transition from the current legacy point to point telemetry links to a network oriented telemetry system. Specifically, identified by the DoD aeronautical telemetry community is the need for a migration to a network solution for command, control, and transfer of test data by optimizing the physical, data link, and network layers. In this paper, we present a network-centric telemetry approach based on variants of 802.11 that leverages the open standards as well as the previous Advanced Range Telemetry (ARTM) work on the physical layer waveform. Specifically, we present a burst modem approach based on the recent AOFDM 802.11a work, a TDMA-like MAC layer approach based on 802.11e, and then add additional MAC layer features to allow for the multi-hop aeronautical environment using a variant of the current working standards of 802.11s. The combined benefits of the variants obtained from 802.11a, 802.11e, and 802.11s address the needs for both spectrum efficiency in the aeronautical environment and the iNET program.

  20. Maximizing coupling-efficiency of high-power diode lasers utilizing hybrid assembly technology

    NASA Astrophysics Data System (ADS)

    Zontar, D.; Dogan, M.; Fulghum, S.; Müller, T.; Haag, S.; Brecher, C.

    2015-03-01

    In this paper, we present hybrid assembly technology to maximize coupling efficiency for spatially combined laser systems. High quality components, such as center-turned focusing units, as well as suitable assembly strategies are necessary to obtain highest possible output ratios. Alignment strategies are challenging tasks due to their complexity and sensitivity. Especially in low-volume production fully automated systems are economically at a disadvantage, as operator experience is often expensive. However reproducibility and quality of automatically assembled systems can be superior. Therefore automated and manual assembly techniques are combined to obtain high coupling efficiency while preserving maximum flexibility. The paper will describe necessary equipment and software to enable hybrid assembly processes. Micromanipulator technology with high step-resolution and six degrees of freedom provide a large number of possible evaluation points. Automated algorithms are necess ary to speed-up data gathering and alignment to efficiently utilize available granularity for manual assembly processes. Furthermore, an engineering environment is presented to enable rapid prototyping of automation tasks with simultaneous data ev aluation. Integration with simulation environments, e.g. Zemax, allows the verification of assembly strategies in advance. Data driven decision making ensures constant high quality, documents the assembly process and is a basis for further improvement. The hybrid assembly technology has been applied on several applications for efficiencies above 80% and will be discussed in this paper. High level coupling efficiency has been achieved with minimized assembly as a result of semi-automated alignment. This paper will focus on hybrid automation for optimizing and attaching turning mirrors and collimation lenses.

  1. On-Site Fabrication Infrastructure to Enable Efficient Exploration and Utilization of Space

    NASA Technical Reports Server (NTRS)

    Howell, Joe T.; Fikes, John C.; McLemore, Carole A.; Good, James E.

    2008-01-01

    Unlike past one-at-a-time mission approaches, system-of-systems infrastructures will be needed to enable ambitious scenarios for sustainable future space exploration and utilization. So what do we do when we get to the moon for sustainable exploration. On-site fabrication infrastructure will be needed to support habitat structure development, tools and mechanical part fabrication, as well as repair and replacement of ground support and space mission hardware such as life support items, vehicle components and crew systems. The on-site fabrication infrastructure will need the In Situ Fabrication and Repair (ISFR) element, which is working in conjunction with the In Situ Resources Utilization (ISRU) element, to live off the land. The ISFR element has worked closely with the ISRU element in the past year to assess the ability of using lunar regolith as a viable feedstock for fabrication material. Preliminary work has shown promise and the ISFR Element will continue to concentrate on this activity. Fabrication capabilities have been furthered with the process certification effort that, when completed, will allow for space-qualified hardware to be manufactured. Materials being investigated include titanium and aluminum alloys as well as lunar regolith simulants with binders. This paper addresses the latest advancements made in the fabrication of infrastructures that support efficient, affordable, reliable infrastructures for both space exploration systems and logistics; infrastructures that allow sustained, affordable and highly effective operations on the Moon and beyond.

  2. A novel glowing electrolyte based on perylene accompany with spectrum compensation function for efficient dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Bai, Sihang; Liang, Liangliang; Wang, Changlei; Mehnane, Hadja Fatima; Bu, Chenghao; You, Sujian; Yu, Zhenhua; Cheng, Nian; Hu, Hao; Liu, Wei; Guo, Shishang; Zhao, Xingzhong

    2015-04-01

    Liquid electrolytes employing fluorescent perylene are prepared and applied in dye sensitized solar cells (DSSCs). Due to the excellent down-shifting property of perylene, photons with short wavelength (from about 350 to 440 nm) can be absorbed and then converted to ones with longer wavelength (from 450 nm to 550 nm) which can be more efficiently utilized by DSSCs. As a result, device with optimal concentration of 0.05 M perylene presents an efficient improvement in the short-circuit current density (Jsc), leading to an increase of 11.6% in the power conversion efficiency (PCE) compared with the reference DSSC based on control electrolyte.

  3. Comparative study of centralized cooperative spectrum sensing in cognitive radio networks

    Microsoft Academic Search

    Kabeer Ahmed; Faisal Bashir; Najum-ul-Hassan; M. Ehsan ul Haq

    2010-01-01

    Fixed spectrum assignment policy is loosing applicability in present wireless networks which demand for efficient usage of spectrum. There is an urgent need to fully exploit the available spectrum. Moreover, regulatory bodies require flexible and adaptable band assignment techniques to tackle for inefficient utilization of spectrum. Cognitive radio (CR) network is a key solution used by organizations to counter the

  4. Efficient utilization of cassava pulp for succinate production by metabolically engineered Escherichia coli KJ122.

    PubMed

    Sawisit, Apichai; Jantama, Sirima Suvarnakuta; Kanchanatawee, Sunthorn; Jantama, Kaemwich

    2015-01-01

    A metabolically engineered Escherichia coli KJ122 was efficiently utilized for succinate production from cassava pulp during batch separate hydrolysis and fermentation (SHF) under simple anaerobic conditions. Succinate concentration of 41.46 ± 0.05 g/L with yield and productivity of 82.33 ± 0.14 g/100 g dry pulp and 0.84 ± 0.02 g/L/h was obtained. In batch simultaneous saccharification and fermentation (SSF), hydrolysis of 12 % (w/v) cassava pulp with an enzyme loading of 2 % AMG + 3 % Cel (v/w) at pH 6.5 was optimized at 39 °C. Succinate concentration of 80.86 ± 0.49 g/L with a yield of 70.34 ± 0.37 g/100 g dry pulp and a productivity of 0.84 ± 0.01 g/L/h was attained using E. coli KJ122. Fed-batch SSF significantly enhanced succinate concentration to 98.63 ± 0.12 g/L at yield and productivity of 71.64 ± 0.97 g/100 g dry pulp and 1.03 ± 0.01 g/L/h. This result indicated an efficient and economical succinate production from cassava pulp using SHF and SSF by the use of E. coli KJ122. PMID:25030337

  5. 78 FR 18374 - Promoting Economic Efficiency in Spectrum Use: WSRD SSG Workshop IV

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-26

    ...Networking and Information Technology Research and Development...Networking and Information Technology Research and Development...Unleashing the Wireless Broadband Revolution, released on June 28, 2010...innovative spectrum-sharing technologies.'' The WSRD has held...

  6. Simian Immunodeficiency Virus Utilizes Human and Sooty Mangabey but Not Rhesus Macaque STRL33 for Efficient Entry

    Microsoft Academic Search

    STEFAN POHLMANN; BENHUR LEE; SILKE MEISTER; MANDY KRUMBIEGEL; GEORGE LESLIE; ROBERT W. DOMS; FRANK KIRCHHOFF

    2000-01-01

    It has been established that many simian immunodeficiency virus (SIV) isolates utilize the orphan receptors GPR15 and STRL33 about as efficiently as the chemokine receptor CCR5 for entry into target cells. Most stud- ies were performed, however, with coreceptors of human origin. We found that SIV from captive rhesus macaques (SIVmac) can utilize both human and simian CCR5 and GPR15

  7. Weatherization Spans the Efficiency Spectrum in Illinois: Weatherization Assistance Close-Up Fact Sheet

    SciTech Connect

    D& R International

    2001-10-10

    Illinois demonstrates its commitment to technology and efficiency through the Weatherization Program. Weatherization uses advanced technologies and techniques to reduce energy costs for low-income families by increasing the energy efficiency of their homes.

  8. Wolbachia Utilize Host Actin for Efficient Maternal Transmission in Drosophila melanogaster

    PubMed Central

    Newton, Irene L. G.; Savytskyy, Oleksandr; Sheehan, Kathy B.

    2015-01-01

    Wolbachia pipientis is a ubiquitous, maternally transmitted bacterium that infects the germline of insect hosts. Estimates are that Wolbachia infect nearly 40% of insect species on the planet, making it the most prevalent infection on Earth. The bacterium, infamous for the reproductive phenotypes it induces in arthropod hosts, has risen to recent prominence due to its use in vector control. Wolbachia infection prevents the colonization of vectors by RNA viruses, including Drosophila C virus and important human pathogens such as Dengue and Chikungunya. Here we present data indicating that Wolbachia utilize the host actin cytoskeleton during oogenesis for persistence within and transmission between Drosophila melanogaster generations. We show that phenotypically wild type flies heterozygous for cytoskeletal mutations in Drosophila profilin (chic221/+ and chic1320/+) or villin (qua6-396/+) either clear a Wolbachia infection, or result in significantly reduced infection levels. This reduction of Wolbachia is supported by PCR evidence, Western blot results and cytological examination. This phenotype is unlikely to be the result of maternal loading defects, defects in oocyte polarization, or germline stem cell proliferation, as the flies are phenotypically wild type in egg size, shape, and number. Importantly, however, heterozygous mutant flies exhibit decreased total G-actin in the ovary, compared to control flies and chic221 heterozygous mutants exhibit decreased expression of profilin. Additionally, RNAi knockdown of profilin during development decreases Wolbachia titers. We analyze evidence in support of alternative theories to explain this Wolbachia phenotype and conclude that our results support the hypothesis that Wolbachia utilize the actin skeleton for efficient transmission and maintenance within Drosophila. PMID:25906062

  9. An aggregated perylene-based broad-spectrum, efficient and label-free quencher for multiplexed fluorescent bioassays.

    PubMed

    Liu, Tao; Hu, Rong; Lv, Yi-Fan; Wu, Yuan; Liang, Hao; Huan, Shuang-Yan; Zhang, Xiao-Bing; Tan, Weihong; Yu, Ru-Qin

    2014-08-15

    Fluorescent sensing systems based on the quenching of fluorophores have found wide applications in bioassays. An efficient quencher will endow the sensing system a high sensitivity. The frequently used quenchers are based on organic molecules or nanomaterials, which usually need tedious synthesizing and modifying steps, and exhibit different quenching efficiencies to different fluorophores. In this work, we for the first time report that aggregated perylene derivative can serve as a broad-spectrum and label-free quencher that is able to efficiently quench a variety of fluorophores, such as green, red and far red dyes labeled on DNA. By choosing nucleases as model biomolecules, such a broad-spectrum quencher was then employed to construct a multiplexed bioassay platform through a label-free manner. Due to the high quenching efficiency of the aggregated perylene, the proposed platform could detect nuclease with high sensitivity, with a detection limit of 0.03U/mL for EcoRV, and 0.05U/mL for EcoRI. The perylene quencher does not affect the activity of nuclease, which makes it possible to design post-addition type bioassay platform. Moreover, the proposed platform allows simultaneous and multicolor analysis of nucleases in homogeneous solution, demonstrating its value of potential application in rapid screening of multiple bio-targets. PMID:24662061

  10. The cost and performance of utility commercial lighting programs. A report from the Database on Energy Efficiency Programs (DEEP) project

    Microsoft Academic Search

    J. Eto; E. Vine; L. Shown; R. Sonnenblick; C. Payne

    1994-01-01

    The objective of the Database on Energy Efficiency Programs (DEEP) is to document the measured cost and performance of utility-sponsored, energy-efficiency, demand-side management (DSM) programs. Consistent documentation of DSM programs is a challenging goal because of problems with data consistency, evaluation methodologies, and data reporting formats that continue to limit the usefulness and comparability of individual program results. This first

  11. Energy Efficiency in Western Utility Resource Plans: Impacts onRegional Resources Assessment and Support for WGA Policies

    SciTech Connect

    Hopper, Nicole; Goldman, Charles; Schlegal, Jeff

    2006-08-01

    In the aftermath of the consumer price shocks and short-term power shortages of the 2000-01 electricity crisis, policymakers and regulators in Western states are placing increased emphasis on integrated resource planning (IRP), resource adequacy and assessment and a diversified portfolio of resources to meet the needs of electricity consumers. In some states, this has led to a resurgence in state and utility commitments to energy efficiency. Increasing interest in acquiring energy efficiency as a power-system resource is also driven by the desire to dampen high growth rates in electricity demand in some Western states, rapid increases in natural gas prices, concerns about the environmental impacts of electricity generation (e.g. water consumption by power plants, air quality), and the potential of energy efficiency to provide utility bill savings for households and businesses (WGA CDEAC 2006). Recognizing the cost-competitiveness and environmental benefits of energy efficiency, the Western Governor's Association (WGA) has set a high priority for energy efficiency, establishing a goal of reducing projected electricity demand by 20% across the West by 2020 in a policy resolution on Clean and Diversified Energy for the West (WGA 2004). Nationally, the need for improved tracking of demand-side resources in load forecasting is formalized in the North American Electric Reliability Council (NERC)'s recently adopted reliability standards, which utilities and regional reliability organizations will need to comply with (NERC 2005a and 2005b). In this study, we examine the treatment of energy efficiency in recent resource plans issued by fourteen investor-owned utilities (IOUs) in the Western United States and Canada. The goals of this study are to: (1) summarize energy-efficiency resources as represented in a large sample of recent resource plans prepared by Western utilities and identify key issues; (2) evaluate the extent to which the information provided in current resource plans can be used to support region-wide resource assessment and tracking of state/utility progress in meeting the WGA's energy-efficiency goals (WGA 2004); and (3) offer recommendations on information and documentation of energy-efficiency resources that should be included in future resource plans to facilitate comparative review and regional coordination. The scope of this report covers projected electric end-use efficiency investments reported in all Western utility resource plans that were publicly available as of February 2006. While a few utilities included additional demand-side resources, such as demand response, in their plans, we do not report that information. However, many of the issues and recommendations in reference to energy efficiency in this report are relevant to other demand-side resources as well. This report is organized as follows. Section 2 outlines the data sources and approach used in this study and conceptualizes methods and metrics for tracking energy-efficiency resources over time. Section 3 presents results from the review of the utility resource plans. Important issues encountered in reviewing the resource plans are discussed in section 4. Finally, section 5 concludes with recommendations for improving the tracking and reporting of energy efficiency in forthcoming resource plans.

  12. Highly efficient rice straw utilization for poly-(?-glutamic acid) production by Bacillus subtilis NX-2.

    PubMed

    Tang, Bao; Lei, Peng; Xu, Zongqi; Jiang, Yongxiang; Xu, Zheng; Liang, Jinfeng; Feng, Xiaohai; Xu, Hong

    2015-10-01

    Lignocellulosic biomass has been identified as an economic and environmental feedstock for future biotechnological production. Here, for the first time, poly-(?-glutamic acid) (PGA) production by Bacillus subtilis NX-2 using rice straw is investigated. Based on two-stage hydrolysis and characteristic consumption of xylose and glucose by B. subtilis NX-2, a co-fermentation strategy was designed to better accumulate PGA in a 7.5L fermentor by two feeding methods. The maximum cumulative respective PGA production and PGA productivity were 73.0±0.5gL(-1) and 0.81gL(-1)h(-1) by the continuous feeding method, with carbon source cost was saved by 84.2% and 42.5% compared with glucose and cane molasse, respectively. These results suggest that rice straw, a type of abundant, low-cost, non-food lignocellulosic feedstock, may be feasibly and efficiently utilized for industrial-scale production of PGA. PMID:26143572

  13. Efficient reduction of complex noise in passive millimeter-wavelength video utilizing Bayesian surprise

    NASA Astrophysics Data System (ADS)

    Mundhenk, T. Nathan; Baron, Josh; Matic, Roy M.

    2011-06-01

    Passive millimeter wavelength (PMMW) video holds great promise given its ability to see targets and obstacles through fog, smoke and rain. However, current imagers produce undesirable complex noise. This can come as a mixture of fast shot (snow like) noise and a slower forming circular fixed pattern. Shot noise can be removed by a simple gain style filter. However, this can produce blurring of objects in the scene. To alleviate this, we measure the amount of Bayesian surprise in videos. Bayesian surprise is feature change in time which is abrupt, but cannot be accounted for as shot noise. Surprise is used to attenuate the shot noise filter in locations of high surprise. Since high Bayesian surprise in videos is very salient to observers, this reduces blurring particularly in places where people visually attend. Fixed pattern noise is removed after the shot noise using a combination of Non-uniformity correction (NUC) and Eigen Image Wavelet Transformation. The combination allows for online removal of time varying fixed pattern noise even when background motion may be absent. It also allows for online adaptation to differing intensities of fixed pattern noise. The fixed pattern and shot noise filters are all efficient allowing for real time video processing of PMMW video. We show several examples of PMMW video with complex noise that is much cleaner as a result of the noise removal. Processed video clearly shows cars, houses, trees and utility poles at 20 frames per second.

  14. FULLSPECTRUM: a new PV wave making more efficient use of the solar spectrum

    Microsoft Academic Search

    A. Luque; A. Martí; A. Bett; V. M. Andreev; C. Jaussaud; J. A. M. van Roosmalen; J. Alonso; A. Räuber; G. Strobl; W. Stolz; C. Algora; B. Bitnar; A. Gombert; P. Wahnon; J. C. Conesa; W. G. J. H. M. van Sark; A. Meijerink; G. P. M. van Klink; K. Barnham; R. Danz; Toby Meyer; I. Luque-Heredia; R. Kenny; C. Christofides; G. Sala; P. Benitez

    2005-01-01

    The project FULLSPECTRUM — an Integrated Project (IP) in the terminology of the European Commission — pursues a better exploitation of the FULL solar SPECTRUM by (1) further developing concepts already scientifically proven but not yet developed and (2) by trying to prove new ones in the search for a breakthrough in photovoltaic (PV) technology. More specific objectives are the

  15. U.S. utilities' experiences with the implementation of energy efficiency programs

    NASA Astrophysics Data System (ADS)

    Goss, Courtney

    In the U.S., many electric utility companies are offering demand-side management (DSM) programs to their customers as ways to save money and energy. However, it is challenging to compare these programs between utility companies throughout the U.S. because of the variability of state energy policies. For example, some states in the U.S. have deregulated electricity markets and others do not. In addition, utility companies within a state differ depending on ownership and size. This study examines 12 utilities' experiences with DSM programs and compares the programs' annual energy savings results that the selected utilities reported to the Energy Information Administration (EIA). The 2009 EIA data suggests that DSM program effectiveness is not significantly affected by electricity market deregulation or utility ownership. However, DSM programs seem to generally be more effective when administered by utilities located in states with energy savings requirements and DSM program mandates.

  16. Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines

    SciTech Connect

    Venkatesan, Krishna

    2011-11-30

    The purpose of this program was to develop low-emissions, efficient fuel-flexible combustion technology which enables operation of a given gas turbine on a wider range of opportunity fuels that lie outside of current natural gas-centered fuel specifications. The program encompasses a selection of important, representative fuels of opportunity for gas turbines with widely varying fundamental properties of combustion. The research program covers conceptual and detailed combustor design, fabrication, and testing of retrofitable and/or novel fuel-flexible gas turbine combustor hardware, specifically advanced fuel nozzle technology, at full-scale gas turbine combustor conditions. This project was performed over the period of October 2008 through September 2011 under Cooperative Agreement DE-FC26-08NT05868 for the U.S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled "Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines". The overall objective of this program was met with great success. GE was able to successfully demonstrate the operability of two fuel-flexible combustion nozzles over a wide range of opportunity fuels at heavy-duty gas turbine conditions while meeting emissions goals. The GE MS6000B ("6B") gas turbine engine was chosen as the target platform for new fuel-flexible premixer development. Comprehensive conceptual design and analysis of new fuel-flexible premixing nozzles were undertaken. Gas turbine cycle models and detailed flow network models of the combustor provide the premixer conditions (temperature, pressure, pressure drops, velocities, and air flow splits) and illustrate the impact of widely varying fuel flow rates on the combustor. Detailed chemical kinetic mechanisms were employed to compare some fundamental combustion characteristics of the target fuels, including flame speeds and lean blow-out behavior. Perfectly premixed combustion experiments were conducted to provide experimental combustion data of our target fuels at gas turbine conditions. Based on an initial assessment of premixer design requirements and challenges, the most promising sub-scale premixer concepts were evaluated both experimentally and computationally. After comprehensive screening tests, two best performing concepts were scaled up for further development. High pressure single nozzle tests were performed with the scaled premixer concepts at target gas turbine conditions with opportunity fuels. Single-digit NOx emissions were demonstrated for syngas fuels. Plasma-assisted pilot technology was demonstrated to enhance ignition capability and provide additional flame stability margin to a standard premixing fuel nozzle. However, the impact of plasma on NOx emissions was observed to be unacceptable given the goals of this program and difficult to avoid.

  17. Energy-efficient office technology: Opportunities for government/utility partnering

    SciTech Connect

    Penner-Fox, P.

    1995-12-01

    Ten years ago office technologies weren`t a recognized end-use market segment. Ten years ago the country was still building nuclear power plants, there was no Energy Policy Act, demand-side management (DSM) had not yet reached its `zenith of rebates,` integrated resource planning was a new concept, and least-cost planning was much more commonly used. The acronyms `IPP` and `NUG` were barely invented. Global warming was much less talked about as an energy and environmental policy concern, and the general perception was that energy was cheap and there were few energy or environmental problems. The United States was busy building the largest government deficit in history and job growth was stagnant. That was the macro-economic environment. In 1994 there is strong job growth-4.2 million- and government has cut $500 billion from the deficit by freezing discretionary spending. In simple terms, there`s no new money and the federal government must do more with less. Competitive pressure in the utility environment is much higher compared with 10 years ago, and restructuring is on everyone`s minds. DSM has gone through incredible changes in 10 years-it`s gone international. The USA has incorporated competitive procurement and the use of energy service companies. The USA has become very smart and sophisticated; programs today are much more elegant than the early programs of the late 1970s and early 1980s. Technology has marched onward and upward. Finally, domestic and global economic environmental problems have increased in most respects. Global climate change is a significant concern-enough to warrant a cautious approach. There are two key elements to moving forward. One of them is win-win policies. Policies must not pit environmental and energy objectives against jobs and economic growth. Given all the constraints, the second key element to achieve win-win policies is with lean and efficient partnerships.

  18. Enforcing Dynamic Spectrum Access with Spectrum Permits

    E-print Network

    California at Santa Barbara, University of

    Enforcing Dynamic Spectrum Access with Spectrum Permits Lei Yang , Zengbin Zhang, Ben Y. Zhao}@cs.ucsb.edu ABSTRACT Dynamic spectrum access is a maturing technology that allows next generation wireless devices to make highly efficient use of wireless spectrum. Spectrum can be allocated on an on-demand basis

  19. Utility of the Psychoeducational Profile-3 for Assessing Cognitive and Language Skills of Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Fulton, Mandy L.; D'Entremont, Barbara

    2013-01-01

    The Psychoeducational Profile-3's (PEP-3) ability to estimate cognitive and language skills of 136 children (20-75 months) with autism spectrum disorders (ASDs) across a range of functioning, and the association between the PEP-3 and ASD symptomatology was examined using retrospective data. PEP-3 cognitive and language measures were…

  20. Comparative study on various radio frequency spectrum sensing techniques

    NASA Astrophysics Data System (ADS)

    Gondesi, Raveendhar Reddy

    2011-12-01

    Cognitive radio (CR) is a self-monitoring wireless communication system. CR can utilize the radio frequency spectrum efficiently. The main objective of cognitive radio is to detect the primary user signal and determine whether a channel is free or not. The CR user can opportunistically use those idle spectrum bands without causing harmful interference to the licensed/primary users. There are several spectrum sensing techniques which can serve this purpose. In this research, the computational complexities for different local spectrum sensing techniques are calculated. Using the results obtained from computational complexities, the energy efficient and time efficient techniques are determined. From the results obtained in local sensing techniques, the cost efficient and bandwidth efficient combination for cooperative spectrum sensing is determined. Using MATLAB programming, the receiver operating characteristic curves for these spectrum sensing techniques are plotted.

  1. Efficient light emitting devices utilizing CdSe(ZnS) quantum dots in organic host matrices

    E-print Network

    Coe-Sullivan, Seth (Seth Alexander)

    2002-01-01

    We demonstrate efficient electroluminescence from thin film structures containing core-shell CdSe(ZnS) quantum dots dispersed in molecular organic host materials. In the most efficient devices, excitons are created on the ...

  2. The Development of Improved Energy Efficient Housing for Thailand Utilizing Renewable Energy Technology 

    E-print Network

    Rasisuttha, S.; Haberl, J.

    2004-01-01

    The paper reports on the results of research to reduce energy consumption in residential buildings in a hot and humid climate region (Thailand) using efficient architectural building components, energy efficient building ...

  3. Optical spectrum of bottom-up graphene nanoribbons: towards efficient atom-thick excitonic solar cells

    NASA Astrophysics Data System (ADS)

    Villegas, Cesar E. P.; Mendonça, P. B.; Rocha, A. R.

    2014-10-01

    Recently, atomically well-defined cove-shaped graphene nanoribbons have been obtained using bottom-up synthesis. These nanoribbons have an optical gap in the visible range of the spectrum which make them candidates for donor materials in photovoltaic devices. From the atomistic point of view, their electronic and optical properties are not clearly understood. Therefore, in this work we carry out ab-initio density functional theory calculations combine with many-body perturbation formalism to study their electronic and optical properties. Through the comparison with experimental measurements, we show that an accurate description of the nanoribbon's optical properties requires the inclusion of electron-hole correlation effects. The energy, binding energy and the corresponding excitonic transitions involved are analyzed. We found that in contrast to zigzag graphene nanoribbons, the excitonic peaks in the absorption spectrum are a consequence of a group of transitions involving the first and second conduction and valence bands. Finally, we estimate some relevant optical properties that strengthen the potential of these nanoribbons for acting as a donor materials in photovoltaic.

  4. Comparison of the lysine utilization efficiency in different plant protein sources supplemented with l-lysine·HCl in rainbow trout ( Oncorhynchus mykiss) fry

    Microsoft Academic Search

    Tran Thi Nang Thu; Charles Parkouda; Sarah de Saeger; Yvan Larondelle; Xavier Rollin

    2007-01-01

    The efficiency of lysine (Lys) utilization has recently received much attention in dietary formulation for fish especially for plant protein based diets. However, it remains unclear whether supplemental Lys utilization is similar in fish fed diets containing different plant protein sources equally limiting in Lys. In the present study, we compared the Lys retention efficiency in rainbow trout fry fed

  5. Plasticity of rhizosphere hydraulic properties as a key for efficient utilization of scarce resources

    PubMed Central

    Carminati, Andrea; Vetterlein, Doris

    2013-01-01

    Background It is known that the soil near roots, the so-called rhizosphere, has physical and chemical properties different from those of the bulk soil. Rhizosphere properties are the result of several processes: root and soil shrinking/swelling during drying/wetting cycles, soil compaction by root growth, mucilage exuded by root caps, interaction of mucilage with soil particles, mucilage shrinking/swelling and mucilage biodegradation. These processes may lead to variable rhizosphere properties, i.e. the presence of air-filled gaps between soil and roots; water repellence in the rhizosphere caused by drying of mucilage around the soil particles; or water accumulation in the rhizosphere due to the high water-holding capacity of mucilage. The resulting properties are not constant in time but they change as a function of soil condition, root growth rate and mucilage age. Scope We consider such a variability as an expression of rhizosphere plasticity, which may be a strategy for plants to control which part of the root system will have a facilitated access to water and which roots will be disconnected from the soil, for instance by air-filled gaps or by rhizosphere hydrophobicity. To describe such a dualism, we suggest classifying rhizosphere into two categories: class A refers to a rhizosphere covered with hydrated mucilage that optimally connects roots to soil and facilitates water uptake from dry soils. Class B refers to the case of air-filled gaps and/or hydrophobic rhizosphere, which isolate roots from the soil and may limit water uptake from the soil as well water loss to the soil. The main function of roots covered by class B will be long-distance transport of water. Outlook This concept has implications for soil and plant water relations at the plant scale. Root water uptake in dry conditions is expected to shift to regions covered with rhizosphere class A. On the other hand, hydraulic lift may be limited in regions covered with rhizosphere class B. New experimental methods need to be developed and applied to different plant species and soil types, in order to understand whether such dualism in rhizosphere properties is an important mechanism for efficient utilization of scarce resources and drought tolerance. PMID:23235697

  6. Financial Impact of Energy Efficiency under a Federal Renewable Electricity Standard: Case Study of a Kansas"super-utility"

    SciTech Connect

    Goldman, Charles A.; Cappers, Peter

    2009-12-01

    Local, state and federal policies that jointly promote the generation of electricity from renewable technologies and the pursuit of energy efficiency are expected to help mitigate the detrimental effects of global climate change and foster energy independence. We examine the financial impacts on various stakeholders from alternative compliance strategies with a Combined Efficiency and Renewable Electricity Standard (CERES) using a case study approach for utilities in Kansas. If only supply-side options are considered, our analysis suggests that a Kansas"super-utility" would prefer to build its own renewable energy resources, while ratepayers would favor a procurement strategy that relies on long-term renewable power purchase agreements. Introducing energy efficiency under varying levels as a CERES resource will, under our analysis, reduce ratepayer bills by ~;;$400M to ~;;$1.0B between 2009 and 2028, but commensurately erode shareholder returns by ~;;10 to ~;;100 basis points. If a business model for energy efficiency inclusive of both a lost fixed cost recovery mechanism and a shareholder incentive mechanism is implemented, our results illustrate how shareholder returns can be improved through the pursuit of energy efficiency, by at most ~;;20 basis points if certain conditions apply, while ratepayers continue to save between $10M and ~;;$840M over 20 years.

  7. Utility and limitations of glypican-3 expression for the diagnosis of hepatocellular carcinoma at both ends of the differentiation spectrum

    Microsoft Academic Search

    Nafis Shafizadeh; Linda D Ferrell; Sanjay Kakar

    2008-01-01

    Glypican-3 is a heparin sulfate proteoglycan normally expressed in fetal liver and placenta, but not in normal adult liver. Preliminary studies have shown that glypican-3 can be useful for the diagnosis of hepatocellular carcinoma. We performed immunohistochemistry for glypican-3 on 80 resection cases of hepatocellular lesions to examine the utility of glypican-3 immunohistochemistry in hepatocellular carcinoma at two ends of

  8. Estimation of DUR and source utilization efficiency for changing product dimensions and source activities in gamma irradiator

    NASA Astrophysics Data System (ADS)

    Reji George, Jain; Pradhan, A. S.

    2009-11-01

    This paper discusses the application of the developed analytical method (Reji George, Jain, Pradhan, A.S., 2008. Theoretical evaluation of dose distribution in product in radiation processing plants. Radiat. Phys. Chem. 77, 186-191), for determining the activity loading pattern in a radiation processing plant to get the desired dose uniformity ratio (DUR) for processing mangoes and how the method was used to evaluate the expected source utilization efficiency for the redesigned source-product configuration.

  9. Protein level does not affect lysine utilization efficiency at marginal lysine intake in growing rainbow trout ( Oncorhynchus mykiss) fry

    Microsoft Academic Search

    Tran Thi Nang Thu; Charles Parkouda; Sarah de Saeger; Yvan Larondelle; Xavier Rollin

    2009-01-01

    The present experiment investigated whether lysine (Lys) utilization efficiency is affected by dietary protein level in rainbow trout when Lys is first limiting in the diet. Eighteen isoenergetic (22.9 MJ digestible energy\\/kg dry matter (DM)) Lys-deficient diets containing 250, 450 or 650 g crude protein\\/kg DM and between 6 and 20 g Lys\\/kg DM were prepared. Wheat gluten, and a crystalline amino acid

  10. Energy Efficiency: Marketing and Service Potential for Energy Utilities' Industrial Markets 

    E-print Network

    Russel, C.; Tate, R.; Tubiolo, A.

    2002-01-01

    superb channel for information outreach to the industrial community, especially if that information is value that attracts and retains customers. In practice, this match-up of industry and utility interests is often difficult to achieve. On the part...

  11. New Irrigation System Design for Maximizing Irrigation Efficiency and Increasing Rainfall Utilization 

    E-print Network

    Lyle, W. M.; Bordovsky, J. P.

    1980-01-01

    through the field in a rectilinear fashion. The system is used in conjunction with micro-basin land preparation which also optimizes the utilization of rainfall. The combined system minimizes the effect of soil and climatic variables which adversely...

  12. A Study About Improvement of Efficiency of a Sewage Heat Utilization System

    NASA Astrophysics Data System (ADS)

    Kobayakawa, Tomoaki; Hihara, Eiji; Hanazaki, Hirotaka

    In order to acquire the basis of technical information that will be required for the design and operation of a sewage heat utilization system, this paper discusses the data analysis of operational performance at the DHC plant in Makuhari HB area. The methodology used in this study is to clarify the characteristics of a sewage heat utilization system from compound characteristics of the DHC plant that consists of various heating systems, and evaluate them.

  13. Efficient, full-spectrum, long-lived, non-toxic microwave lamp for plant growth

    NASA Technical Reports Server (NTRS)

    Maclennan, Donald A.; Turner, Brian P.; Dolan, James T.; Ury, Michael G.; Gustafson, Paul

    1994-01-01

    Fusion Systems Corporation has developed a mercury-free, low infrared, efficient microwave lamp using a benign sulfur based fill optimized for visible light. Our literature search and discussions with researchers directed us to enhance the bulbs red output. We have demonstrated a photosynthetic efficacy of over 2 micro-moles per microwave joule which corresponds to over 1.3 micro-moles per joule at the power main. Recent work has shown we can make additional increases in overall system efficiency. During the next two years, we expect to demonstrate a system capable of producing more than 1.5 micro-moles/joule measured at the power main with significantly less IR than alternative lamp systems. We determined optimal plant growth light requirements via a literature search and researcher input. We surveyed candidate lamp fill materials to be used in combination with sulfur and explored several methods of increasing photosynthetic efficacy.

  14. LightForce Photon-Pressure Collision Avoidance: Updated Efficiency Analysis Utilizing a Highly Parallel Simulation Approach

    NASA Astrophysics Data System (ADS)

    Stupl, J.; Faber, N.; Foster, C.; Yang, F.; Nelson, B.; Aziz, J.; Nuttall, A.; Henze, C.; Levit, C.

    2014-09-01

    This paper provides an updated efficiency analysis of the LightForce space debris collision avoidance scheme. LightForce aims to prevent collisions on warning by utilizing photon pressure from ground based, commercial off the shelf lasers. Past research has proven that a few ground-based systems consisting of 10 kW class lasers directed by 1.5 m telescopes with adaptive optics could lower the expected number of collisions in Low Earth Orbit (LEO) by an order of magnitude. Our simulation approach utilizes the entire Two Line Element (TLE) catalogue in LEO for a given day as initial input. Least-squares fitting of a TLE time series is used for an improved orbit estimate. We then calculate the probability of collision for all LEO objects in the catalogue for a time step of the simulation. The conjunctions that exceed a threshold probability of collision are then engaged by a simulated network of laser ground stations. After those engagements, the perturbed orbits are used to re-assess the probability of collision and evaluate the efficiency. This paper describes new simulations with three updated aspects: 1) By utilizing a highly parallel simulation approach employing hundreds of processors, we have extended our analysis to a much broader dataset. The simulation time is extended to one year. 2) We analyze not only the efficiency of LightForce on conjunctions that naturally occur, but also take into account conjunctions caused by orbit perturbations due to LightForce engagements. 3) We use a new simulation approach that is regularly updating the LightForce engagement strategy, as it would be during actual operations. In this paper we present both our simulation approach to parallelize the efficiency analysis, its computational performance and the resulting expected efficiency of the LightForce collision avoidance system.

  15. An Auction Framework for Spectrum Allocation with Interference Constraint in Cognitive Radio Networks

    E-print Network

    Coupechoux, Marceau

    , the SUs share the available spectrum of This work is supported by the project TEROPP (technologies for TER1 An Auction Framework for Spectrum Allocation with Interference Constraint in Cognitive Radio to improve the flexibility and efficiency of spectrum utilization. This new communication paradigm, however

  16. Optimal Linear Cooperation for Spectrum Sensing in Cognitive Radio Networks

    Microsoft Academic Search

    Zhi Quan; Shuguang Cui; Ali H. Sayed

    2008-01-01

    Cognitive radio technology has been proposed to improve spectrum efficiency by having the cognitive radios act as secondary users to opportunistically access under-utilized frequency bands. Spectrum sensing, as a key enabling functionality in cognitive radio networks, needs to reliably detect signals from licensed primary radios to avoid harmful interference. However, due to the effects of channel fading\\/shadowing, individual cognitive radios

  17. Resource-efficient fusion with pre-compensated transmissions for cooperative spectrum sensing.

    PubMed

    Guimarães, Dayan Adionel; Aquino, Guilherme Pedro; Cattaneo, Marco E G V

    2015-01-01

    Recently, a novel fusion scheme for cooperative spectrum sensing was proposed for saving resources in the control channel. Secondary users (SUs) simultaneously report their decisions using binary modulations with the same carrier frequencies. The transmitted symbols add incoherently at the fusion centre (FC), leading to a larger set of symbols in which a subset is associated with the presence of the primary user (PU) signal, and another subset is associated with the absence of such a signal. The decision criterion applied for discriminating these subsets works under the assumption that the channel gains are known at the FC. In this paper, we propose a new simultaneous transmission and decision scheme in which the task of channel estimation is shifted from the FC to the SUs, without the need for feeding-back of the estimates to the FC. The estimates are used at the SUs to pre-compensate for the reporting channel phase rotations and to partially compensate for the channel gains. This partial compensation is the result of signal clipping for peak-to-average power ratio (PAPR) control. We show, analytically and with simulations, that this new scheme can produce large performance improvements, yet reduces the implementation complexity when compared with the original one. PMID:26007712

  18. Resource-Efficient Fusion with Pre-Compensated Transmissions for Cooperative Spectrum Sensing

    PubMed Central

    Guimarães, Dayan Adionel; Aquino, Guilherme Pedro; Cattaneo, Marco E. G. V.

    2015-01-01

    Recently, a novel fusion scheme for cooperative spectrum sensing was proposed for saving resources in the control channel. Secondary users (SUs) simultaneously report their decisions using binary modulations with the same carrier frequencies. The transmitted symbols add incoherently at the fusion centre (FC), leading to a larger set of symbols in which a subset is associated with the presence of the primary user (PU) signal, and another subset is associated with the absence of such a signal. The decision criterion applied for discriminating these subsets works under the assumption that the channel gains are known at the FC. In this paper, we propose a new simultaneous transmission and decision scheme in which the task of channel estimation is shifted from the FC to the SUs, without the need for feeding-back of the estimates to the FC. The estimates are used at the SUs to pre-compensate for the reporting channel phase rotations and to partially compensate for the channel gains. This partial compensation is the result of signal clipping for peak-to-average power ratio (PAPR) control. We show, analytically and with simulations, that this new scheme can produce large performance improvements, yet reduces the implementation complexity when compared with the original one. PMID:26007712

  19. Program experience and its regulatory implications: A case study of utility lighting efficiency programs

    SciTech Connect

    Krause, F.; Vine, E.; Gandhi, S.

    1989-10-01

    This report takes an approach to utility demand-side program experience that differs from previous work in both focus and methodology. The assessment of program experience is limited to one specific end-use of electricity, i.e. lighting. Program approaches of a limited number of exemplary or illustrative programs are described and analyzed in depth. And the lessons learned about how to conduct effective programs are reviewed in terms of the implications for the evolving practice of least-cost utility planning (LCUP). 3 refs., 1 fig., 5 tabs.

  20. Utility Goals for the Efficiency Resource: Impact of PUC Rulemaking Project No. 39674 on Future Programs

    E-print Network

    Martin, A.

    2012-01-01

    language clarifies that performance bonuses are included in program costs Bonus and EM&V Costs should be included in the calculation (what about other costs related to EECRFs [utility/muni EECRF proceeding expenses]?) Avoided Costs (d)(2) and (3) (d)(2... spending caps Explicitly states util ity EECRF costs won't count against 20% max admin cap. What about muni EECRF expenses (assuming they would not count against it based on precedent...?). EM&V NA (q) New section to the rule; PUC will hire...

  1. Encouraging the construction of energy-efficient homes. A utility perspective

    Microsoft Academic Search

    G. H. Jr. Kimmons; P. W. Burch

    1985-01-01

    Historically an industry with a supply side orientation, electric utilities are becoming increasingly involved with the end usage, or demand side, of their product as a means of effectively managing their systems. The Tennessee Valley Authority (TVA) has been actively involved in a variety of demand side energy conservation and management programs since 1977. One such program, designed to encourage

  2. Energy Conversion Efficiency of a Novel Hybrid Solar System for Photovoltaic, Thermoelectric, and Heat Utilization

    Microsoft Academic Search

    Dajiang Yang; Huiming Yin

    2011-01-01

    A novel hybrid solar system has been designed to utilize photovoltaic (PV) cells, thermoelectric (TE) modules, and hot water (HW) through a multilayered building envelope. Water pipelines are cast within a functionally graded material layer to serve as a heat sink, allowing heat to be easily transferred into flowing water through an aluminum-rich surface, while remain- ing insulated by a

  3. The Development of Improved Energy Efficient Housing for Thailand Utilizing Renewable Energy Technology

    E-print Network

    Rasisuttha, S.; Haberl, J.

    would seem to be ideal for Thai- land since Thailand is located near the equator and has high levels of sunshine year-round. Bangkok?s monthly average daily radiation on a horizontal surface varies little from January to December (ranging from 16... The paper reports on the results of research to reduce energy consumption in residential buildings in a hot and humid climate region (Thailand) using efficient architectural building components, energy efficient building systems, and renewable energy...

  4. LightForce Photon-Pressure Collision Avoidance: Updated Efficiency Analysis Utilizing a Highly Parallel Simulation Approach

    NASA Technical Reports Server (NTRS)

    Stupl, Jan; Faber, Nicolas; Foster, Cyrus; Yang, Fan Yang; Nelson, Bron; Aziz, Jonathan; Nuttall, Andrew; Henze, Chris; Levit, Creon

    2014-01-01

    This paper provides an updated efficiency analysis of the LightForce space debris collision avoidance scheme. LightForce aims to prevent collisions on warning by utilizing photon pressure from ground based, commercial off the shelf lasers. Past research has shown that a few ground-based systems consisting of 10 kilowatt class lasers directed by 1.5 meter telescopes with adaptive optics could lower the expected number of collisions in Low Earth Orbit (LEO) by an order of magnitude. Our simulation approach utilizes the entire Two Line Element (TLE) catalogue in LEO for a given day as initial input. Least-squares fitting of a TLE time series is used for an improved orbit estimate. We then calculate the probability of collision for all LEO objects in the catalogue for a time step of the simulation. The conjunctions that exceed a threshold probability of collision are then engaged by a simulated network of laser ground stations. After those engagements, the perturbed orbits are used to re-assess the probability of collision and evaluate the efficiency of the system. This paper describes new simulations with three updated aspects: 1) By utilizing a highly parallel simulation approach employing hundreds of processors, we have extended our analysis to a much broader dataset. The simulation time is extended to one year. 2) We analyze not only the efficiency of LightForce on conjunctions that naturally occur, but also take into account conjunctions caused by orbit perturbations due to LightForce engagements. 3) We use a new simulation approach that is regularly updating the LightForce engagement strategy, as it would be during actual operations. In this paper we present our simulation approach to parallelize the efficiency analysis, its computational performance and the resulting expected efficiency of the LightForce collision avoidance system. Results indicate that utilizing a network of four LightForce stations with 20 kilowatt lasers, 85% of all conjunctions with a probability of collision Pc > 10 (sup -6) can be mitigated.

  5. A ROBUST ABSOLUTE DETECTION EFFICIENCY CALIBRATION METHOD UTILIZING BETA/GAMMA COINCIDENCE SIGNATURES AND ISOTOPICALLY PURIFIED NEUTRON ACTIVATED RADIOXENON ISOTOPES

    SciTech Connect

    McIntyre, Justin I.; Cooper, Matthew W.; Ely, James H.; Haas, Derek A.; Schrom, Brian T.

    2012-09-21

    Efforts to calibrate the absolute efficiency of gas cell radiations detectors have utilized a number of methodologies which allow adequate calibration but are time consuming and prone to a host of difficult-to-determine uncertainties. A method that extrapolates the total source strength from the measured beta and gamma gated beta coincidence signal was developed in the 1960’s and 1970’s. It has become clear that it is possible to achieve more consistent results across a range of isotopes and a range of activities using this method. Even more compelling is the ease with which this process can be used on routine samples to determine the total activity present in the detector. Additionally, recent advances in the generation of isotopically pure radioxenon samples of Xe-131m, Xe-133, and Xe-135 have allowed these measurement techniques to achieve much better results than would have been possible before when using mixed isotopic radioxenon source. This paper will discuss the beta/gamma absolute detection efficiency technique that utilizes several of the beta-gamma decay signatures to more precisely determine the beta and gamma efficiencies. It will than compare these results with other methods using pure sources of Xe-133, Xe-131m, and Xe-135 and a Xe-133/Xe-133m mix.

  6. Evaluation of Energy Saving Characteristics of a High-Efficient Cogeneration System Utilizing Gas Engine Exhaust Heat

    NASA Astrophysics Data System (ADS)

    Pak, Pyong Sik

    A high efficiency cogeneration system (CGS) utilizing high temperature exhaust gas from a gas engine is proposed. In the proposed CGS, saturated steam produced in the gas engine is superheated with a super heater utilizing regenerative burner and used to drive a steam turbine generator. The heat energy is supplied by extracting steam from the steam turbine and turbine outlet low-temperature steam. Both of the energy saving characteristics of the proposed CGS and a CGS constructed by using the original gas engine (GE-CGS) were investigated and compared, by taking a case where energy for office buildings was supplied by the conventional energy systems. It was shown that the proposed CGS has energy saving rate of 24.5%, higher than 1.83 times, compared with that of the original GE-CGS.

  7. Utility Goals for the Efficiency Resource: Impact of PUC Rulemaking Project No. 39674 on Future Programs 

    E-print Network

    Martin, A.

    2012-01-01

    Opened 2) September 2011 ? Strawman Issued 3) April 2012 ? Proposal for Publication 4) September 2012 ? Proposal for Adoption Issue Proposal for Adoption (PFA) Summary Notes/Implications Current Rule PFA Preamble Q1: Transition LM to ERCOT NA NA... NA LM is safe; mandatory transition is not appropriate at this time; no caps applied Preamble Q2: Performance Standards; Equipment Incentives NA NA NA Current standards are approved; util ities should continue to develop own performance standards...

  8. Efficient operation of a chemically pumped oxygen iodine laser utilizing dilute hydrogen peroxide

    Microsoft Academic Search

    S. Yoshida; H. Fujii; T. Sawano; M. Endo; T. Fujioka

    1987-01-01

    A chemically pumped oxygen iodine laser system has been operated employing 35 wt pct H2O2 rather than commonly used 90 wt pct H2O2. Laser power as high as 40 W has been extracted. The maximum overall efficiency of 20.7 percent, which is almost 25 percent higher than the previously reported best data, has been achieved.

  9. Efficient Feed Nutrient Utilization to Reduce Pollutants in Poultry and Swine Manure

    Microsoft Academic Search

    K. H. Nahm

    2002-01-01

    High-density livestock facilities lead to a concentration of livestock wastes and subsequent leakage of pollutants into the environment, resulting in public concern about their effects. Nitrogen (N) and phosphorus (P) are the most harmful components of animal manure, but odor from the manure itself and the livestock facilities is also a problem. Improving the nutrient efficiency of the livestock helps

  10. Effect of larval density on food utilization efficiency of Tenebrio molitor (Coleoptera: Tenebrionidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rearing conditions, particularly the crowding of larvae, may have a significant impact on production efficiency of some insects produced commercially, such as Tenebrio molitor L. (Coleoptera: Tenebrionidae). Although larval densities are known to affect developmental time and growth in T. molitor, n...

  11. PARTICULATE COLLECTION EFFICIENCY MEASUREMENTS ON AN ESP INSTALLED ON A COAL-FIRED UTILITY BOILER

    EPA Science Inventory

    The report gives results of fractional and overall collection efficiency measurements of an electrostatic precipitator collecting fly ash from a coal-fired boiler burning high-sulfur coal. The mass median diameter of the particulate entering the collector was approximately 40 mic...

  12. POSSIBILITY OF EFFICIENT UTILIZATION OF WOOD WASTE AS A RENEWABLE ENERGY RESOURCE IN SERBIA

    Microsoft Academic Search

    Bojan ?er?an; Tamara Luki?; Milka Bubalo-Živkovi?; Branislav ?ur?ev; Rastislav Stojsavljevi?; Milana Panteli?

    2012-01-01

    Wood biomass in Serbia is traditionally used for energy. However, the manner of its use is outdated, and efficiency is very low. Annually over 3.5 million m3 of wood is cut down for energy needs in Serbia. In order to better exploit all forms of woody biomass, especially the one that is now treated as waste, and in order to

  13. Utilizing fast multipole expansions for efficient and accurate quantum-classical molecular dynamics simulations.

    PubMed

    Schwörer, Magnus; Lorenzen, Konstantin; Mathias, Gerald; Tavan, Paul

    2015-03-14

    Recently, a novel approach to hybrid quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) simulations has been suggested [Schwörer et al., J. Chem. Phys. 138, 244103 (2013)]. Here, the forces acting on the atoms are calculated by grid-based density functional theory (DFT) for a solute molecule and by a polarizable molecular mechanics (PMM) force field for a large solvent environment composed of several 10(3)-10(5) molecules as negative gradients of a DFT/PMM hybrid Hamiltonian. The electrostatic interactions are efficiently described by a hierarchical fast multipole method (FMM). Adopting recent progress of this FMM technique [Lorenzen et al., J. Chem. Theory Comput. 10, 3244 (2014)], which particularly entails a strictly linear scaling of the computational effort with the system size, and adapting this revised FMM approach to the computation of the interactions between the DFT and PMM fragments of a simulation system, here, we show how one can further enhance the efficiency and accuracy of such DFT/PMM-MD simulations. The resulting gain of total performance, as measured for alanine dipeptide (DFT) embedded in water (PMM) by the product of the gains in efficiency and accuracy, amounts to about one order of magnitude. We also demonstrate that the jointly parallelized implementation of the DFT and PMM-MD parts of the computation enables the efficient use of high-performance computing systems. The associated software is available online. PMID:25770527

  14. EFFECTS OF COMBUSTION MODIFICATIONS FOR NOX CONTROL ON UTILITY BOILER EFFICIENCY AND COMBUSTION STABILITY

    EPA Science Inventory

    The report gives results of an evaluation of the possibility that plant efficiency losses or combustion instability might limit NOx reduction by combustion modification. Data from natural-gas- and oil-fired boilers were used in the analyses. The study of effects on plant efficien...

  15. The Utility of an Efficient Outcomes Assessment System at University Counseling Centers

    ERIC Educational Resources Information Center

    Kopta, S. Mark; Petrik, Megan L.; Saunders, Stephen M.; Mond, Michael; Hirsch, Glenn; Kadison, Richard; Raymond, Danielle

    2014-01-01

    Due to increased demands placed on university counseling centers (UCCs) in recent years, there is a need for these centers to enhance the efficiency and effectiveness of their psychological services. Regularly monitoring client progress is one approach to increase the likelihood of positive clinical outcomes. This article describes the use of the…

  16. PS1-39: Health Care Utilization for Children With and Without Autism Spectrum Disorders in Five Large Health Systems

    PubMed Central

    Lynch, Frances; Cummings, Janet; Rust, Kristal; Owen-Smith, Ashli; Coleman, Karen; Madden, Jeanne; Yau, Vincent; Pearson, Kathy; Crawford, Phillip; Massolo, Maria; Quinn, Virginia; Croen, Lisa

    2014-01-01

    Background/Aims Approximately 1 in 88 children in the U.S. is diagnosed with Autism Spectrum Disorder (ASD). ASD is a complex disorder characterized by impairment in social skills, communication, and cognitive and behavioral functioning. Several studies have indicated that children with ASD use a different pattern of health services than typically developing children. However, most previous studies have included small samples, or only included one health system. The purpose of this analysis is to examine patterns of health service use in a large group of geographically- and racially/ethnically-diverse children with ASD enrolled in the Mental Health Research Network (MHRN) Autism Registry. Methods Data from 2009 and 2010 from the virtual data warehouse (VDW) of 5 health plans was used to collect comprehensive information on patterns of health services for children with ASD and a comparison group of children without ASD. Comparisons of the patterns of service use in the two groups were conducted. Two part models of service use were used. In the first stage, logistic regression was used to examine the likelihood of any use of services. In the second stage, negative binomial regression was used to examine the level of use services. Results The study includes 8,363 children with ASD and 83,575 comparison children, making it the largest study of patterns of ASD service use to date. Preliminary results indicate that children with ASD were significantly more likely to use most types of services including speech therapy (OR 12.2; 95% CI 10.9–13.9), mental health (OR 8.9; 95% CI 8.4–9.5), and neurology (OR 8.3; 95% CI 7.6–9.1). In contrast, they were significantly less likely to use some services including vaccinations (OR .80; 95% CI .75–.85). Conclusions Children with ASD have significant physical and mental health needs related to their condition and these are reflected in increased use of services in many categories. However, in some cases children with ASD receive fewer important health care services, notably vaccinations. Better understanding of the needs of children with ASD, family beliefs and preferences, and systematic coordination of care for these children could aid in helping families to use health care services most effectively.

  17. Efficient utilization of red maple lumber in glued-laminated timber beams. Forest Service research paper

    SciTech Connect

    Janowiak, J.J.; Manbeck, H.B.; Hernandez, R.; Moody, R.C.; Blankenhorn, P.R.

    1995-09-01

    The feasibility of utilizing cant-sawn hardwood lumber, which would not usually be desired for furniture manufacture, was studied for the manufacture of structural glue-laminated (glulam) timber. Two red maple beam combinations were evaluated. Test results of 42 red maple glulam beams showed that it was feasible to develop structural glulam timber from cant-swan lumber. The glulam combinations made from E-rated lumber exceeded the target design bending stress of 2,400 lb/in 2 and met the target modulus of elasticity (MOE) of 1.8 x 106 lb/in 2.

  18. Utilization Patterns of Conventional and Complementary/Alternative Treatments in Children with Autism Spectrum Disorders and Developmental Disabilities in a Population-Based Study

    PubMed Central

    Akins, CDR Roger Scott; Krakowiak, Paula; Angkustsiri, Kathleen; Hertz-Picciotto, Irva; Hansen, Robin L.

    2014-01-01

    Objective This study compared the utilization of conventional treatments to utilization of complementary and alternative medicine (CAM) in preschoolers with autism spectrum disorders (ASD) and other developmental disabilities (DD). Methods Participants were 578 children who were part of an ongoing population-based, case-control study of 2 to 5 year-olds with ASD, DD, and the general population. Parents completed an interview on past and current services. Results Four hundred fifty-three children with ASD and 125 DD children were included. ASD families received more hours of conventional services compared to DD (17.8 vs. 11; p<0.001). The use of psychotropic medications was low in both groups (~3%). CAM use overall was not significantly different in ASD (39%) versus DD (30%). Hispanic families in both groups used CAM less often than non-Hispanics. Variables such as level of function, immunization status, and presence of an identified neurogenetic disorder were not predictive of CAM use. A higher level of parental education was associated with increased CAM use in ASD and DD. Families who utilized >20 hours per week of conventional services were more likely to use CAM, including potentially unsafe or disproven CAM. Under-immunized children were marginally more likely to use CAM, but not more likely to have received potentially unsafe or disproven CAM. Conclusion CAM use is common in families of young children with neurodevelopmental disorders and is predicted by higher parental education and non-Hispanic ethnicity but not developmental characteristics. Further research should address how healthcare providers can support families in making decisions about CAM use. PMID:24399100

  19. Increased efficiency of rf-induced evaporative cooling by utilizing gravity

    SciTech Connect

    Klinner, Julian; Wolke, Matthias; Hemmerich, Andreas [Institut fuer Laserphysik, Universtiaet Hamburg, Luruper Chaussee 149, D-22761 Hamburg (Germany)

    2010-04-15

    We report on an efficient rf-induced forced evaporative cooling of an ensemble of {sup 87}Rb atoms in state |F=2,m{sub F}=2> magnetically trapped in a quadrupole-Ioffe configuration trap. The cigar-shaped trap is oriented with its weak confining axis along the direction of gravity leading to, first, a significant separation of the trapping positions for low-field-seeking atoms with different m{sub F} value and, second, a reduced resonance volume for rf-induced evaporation confined to a small region around the lower tip of the cigar-shaped ensemble. This results in an enhancement of the evaporation efficiency {alpha}{identical_to}dlnT/(dlnN) due to either reduced or completely vanishing scattering events between cooled and evaporated atoms. We present data illustrating this effect.

  20. Biomimetic antireflection coating for efficiency enhancement of triple-junction solar cells utilizing nanosphere lithography

    Microsoft Academic Search

    M. Y. Chiu; F. Y. Chang; C. H. Chang; M. A. Tsai; Peichen Yu

    2010-01-01

    In this work, we demonstrate a thorough device design, fabrication, characterization, and analysis of biomimetic antireflective structures implemented on a Ga0.5In0.5P\\/GaAs\\/Ge triple-junction solar cell. The sub-wavelength structures are fabricated on a silicon nitride passivation layer using polystyrene nanosphere lithography followed by anisotropic etching. Both the reflectance spectroscopy and external quantum efficiency measurements confirm the improved optical absorption in the ultraviolet\\/blue

  1. An Efficient Storage Utilization for High-Quality Content Distribution in a PVR-Based Community

    Microsoft Academic Search

    Sungwook Chung; Eunsam Kim; Jonathan C. L. Liu

    2009-01-01

    High-quality content can be distributed and shared efficiently in community networks by the advantages of the geographical coverage and the connected community members. Recently, we have proposed a Personal video recorder (PVR)-based community network employing the multiple-loop fiber channel arbitration loop (FC-AL) connection, which can provide the scalability without using expensive FC-AL switches. As a community network size grows, however,

  2. Novel strategies for biobased feedstock utilization: Efficiency, optimization and production of a platform chemical

    Microsoft Academic Search

    F. W. Koopman

    2010-01-01

    Due to evident environmental, economical and political reasons, it is becoming inevitable to shift society’s dependence away from fossil towards renewable, bio-based resources.\\u000aHowever, for efficient implementation of biobased resources, cost effectiveness is key. In this thesis, different possibilities were investigated that may contribute to the economical and technical feasibility of employing (lignocellulosic) biomass as feedstock for chemicals production.\\u000aIn

  3. Efficiency of lasers utilizing vapors of complex organic compounds subjected to hard ultraviolet (266 nm) pumping

    Microsoft Academic Search

    A. P. Ermachenok; O. A. Logunov; A. V. Startsev; Iu. Iu. Stoilov

    1983-01-01

    The efficiency of stimulated emission in the range 329-400 and 500 nm by a series of complex organic compounds in gaseous mixtures with pentane (1.5 x 10 to the 21st\\/cu cm) is measured for the case where the vapor is excited by the fourth harmonic of neodymium laser radiation (266 nm, 5 nsec, 20 mJ). Lasing is observed of PPD

  4. Efficiency of lasers utilizing vapors of complex organic compounds subjected to hard ultraviolet (266 nm) pumping

    Microsoft Academic Search

    A P Ermachenok; O A Logunov; Aleksandr V Startsev; Yu Yu Sto?lov

    1983-01-01

    Measurements were made of the efficiency of stimulated emission in the range 329–400 and 500 nm by a series of complex organic compounds in gaseous mixtures with pentane (1.5×1021cm?3) when the vapor was excited by the fourth harmonic of neodymium laser radiation (266 nm, 5 nsec, 20 mJ). Lasing of PPD (340 nm) and PBD (352 nm) vapors was observed

  5. Light requirement and photosynthetic cell cultivation – Development of processes for efficient light utilization in photobioreactors

    Microsoft Academic Search

    James C. Ogbonna; Hideo Tanaka

    2000-01-01

    Although the potential of photosyntheticmicroorganisms for production of various metabolitesand in environmental bioremediation is recognized,their practical application has been limited by thedifficulty in supplying light efficiently tophotobioreactors. Various types of photobioreactorwith high illumination to volume ratios have beenproposed, but most are limited by cost, mass transfer,contamination, scale-up or a combination of these.The problem of light supply to photobioreactorscan be solved

  6. Full solar spectrum light driven thermocatalysis with extremely high efficiency on nanostructured Ce ion substituted OMS-2 catalyst for VOCs purification

    NASA Astrophysics Data System (ADS)

    Hou, Jingtao; Li, Yuanzhi; Mao, Mingyang; Yue, Yuanzheng; Greaves, G. Neville; Zhao, Xiujian

    2015-01-01

    The nanostructured Ce ion substituted cryptomelane-type octahedral molecular sieve (OMS-2) catalyst exhibits strong absorption in the entire solar spectrum region. The Ce ion substituted OMS-2 catalyst can efficiently transform the absorbed solar energy to thermal energy, resulting in a considerable increase of temperature. By combining the efficient photothermal conversion and thermocatalytic activity of the Ce ion substituted OMS-2 catalyst, we carried out full solar spectrum, visible-infrared, and infrared light driven catalysis with extremely high efficiency. Under the irradiation of full solar spectrum, visible-infrared, and infrared light, the Ce ion substituted OMS-2 catalyst exhibits extremely high catalytic activity and excellent durability for the oxidation of volatile organic pollutants such as benzene, toluene, and acetone. Based on the experimental evidence, we propose a novel mechanism of solar light driven thermocatalysis for the Ce ion substituted OMS-2 catalyst. The reason why the Ce ion substituted OMS-2 catalyst exhibits much higher catalytic activity than pure OMS-2 and CeO2/OMS-2 nano composite under the full solar spectrum irradiation is discussed.The nanostructured Ce ion substituted cryptomelane-type octahedral molecular sieve (OMS-2) catalyst exhibits strong absorption in the entire solar spectrum region. The Ce ion substituted OMS-2 catalyst can efficiently transform the absorbed solar energy to thermal energy, resulting in a considerable increase of temperature. By combining the efficient photothermal conversion and thermocatalytic activity of the Ce ion substituted OMS-2 catalyst, we carried out full solar spectrum, visible-infrared, and infrared light driven catalysis with extremely high efficiency. Under the irradiation of full solar spectrum, visible-infrared, and infrared light, the Ce ion substituted OMS-2 catalyst exhibits extremely high catalytic activity and excellent durability for the oxidation of volatile organic pollutants such as benzene, toluene, and acetone. Based on the experimental evidence, we propose a novel mechanism of solar light driven thermocatalysis for the Ce ion substituted OMS-2 catalyst. The reason why the Ce ion substituted OMS-2 catalyst exhibits much higher catalytic activity than pure OMS-2 and CeO2/OMS-2 nano composite under the full solar spectrum irradiation is discussed. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06410k

  7. Influence of heat recuperation in ORC power plant on efficiency of waste heat utilization

    NASA Astrophysics Data System (ADS)

    Borsukiewicz-Gozdur, Aleksandra

    2010-10-01

    The present work is devoted to the problem of utilization of the waste heat contained in the exhaust gases having the temperature of 350 °C. Conversion of the waste heat into electricity using a power plant working with organic fluid cycles is considered. Three Organic Rankine Cycle (ORC) power plant solutions are analysed and compared: a solution with the basic, single thermodynamic conversion cycle, one with internal heat recuperation and one with external heat recuperation. It results from the analysis that it is the proper choice of the working fluid evaporation temperature that fundamentally affects the maximum of the ORC plant output power. Application of the internal heat recuperation in the plant basic cycle results in the output power increase of approx. 5%. Addition of the external heat recuperation to the plant basic cycle, in the form of a secondary supercritical ORC power cycle can rise the output power by approx. 2%.

  8. The 58-kilodalton major virulence factor of Francisella tularensis is required for efficient utilization of iron.

    PubMed

    Lindgren, Helena; Honn, Marie; Golovlev, Igor; Kadzhaev, Konstantin; Conlan, Wayne; Sjöstedt, Anders

    2009-10-01

    We investigated the role of the 58-kDa FTT0918 protein in the iron metabolism of Francisella tularensis. The phenotypes of SCHU S4, a prototypic strain of F. tularensis subsp. tularensis, and the Delta FTT0918 and Delta fslA isogenic mutants were analyzed. The gene product missing in the Delta fslA mutant is responsible for synthesis of a siderophore. When grown in broth with various iron concentrations, the two deletion mutants generally reached lower maximal densities than SCHU S4. The Delta FTT0918 mutant, but not the Delta fslA mutant, upregulated the genes of the F. tularensis siderophore locus (fsl) operon even at high iron concentrations. A chrome azurol sulfonate plate assay confirmed siderophore production by all strains except the Delta fslA strain. In a cross-feeding experiment using medium devoid of free iron, SCHU S4 promoted growth of the Delta fslA strain but not of the Delta FTT0918 strain. The sensitivity of SCHU S4 and the Delta FTT0918 and Delta fslA strains to streptonigrin demonstrated that the Delta FTT0918 strain contained a smaller free intracellular iron pool and that the Delta fslA strain contained a larger one than SCHU S4. In contrast to the marked attenuation of the Delta FTT0918 strain, the Delta fslA strain was as virulent as SCHU S4 in a mouse model. Altogether, the data demonstrate that the FTT0918 protein is required for F. tularensis to utilize iron bound to siderophores and that it likely has a role also in siderophore-independent iron acquisition. We suggest that the FTT0918 protein be designated Fe utilization protein A, FupA. PMID:19651867

  9. The 58-Kilodalton Major Virulence Factor of Francisella tularensis Is Required for Efficient Utilization of Iron?

    PubMed Central

    Lindgren, Helena; Honn, Marie; Golovlev, Igor; Kadzhaev, Konstantin; Conlan, Wayne; Sjöstedt, Anders

    2009-01-01

    We investigated the role of the 58-kDa FTT0918 protein in the iron metabolism of Francisella tularensis. The phenotypes of SCHU S4, a prototypic strain of F. tularensis subsp. tularensis, and the ?FTT0918 and ?fslA isogenic mutants were analyzed. The gene product missing in the ?fslA mutant is responsible for synthesis of a siderophore. When grown in broth with various iron concentrations, the two deletion mutants generally reached lower maximal densities than SCHU S4. The ?FTT0918 mutant, but not the ?fslA mutant, upregulated the genes of the F. tularensis siderophore locus (fsl) operon even at high iron concentrations. A chrome azurol sulfonate plate assay confirmed siderophore production by all strains except the ?fslA strain. In a cross-feeding experiment using medium devoid of free iron, SCHU S4 promoted growth of the ?fslA strain but not of the ?FTT0918 strain. The sensitivity of SCHU S4 and the ?FTT0918 and ?fslA strains to streptonigrin demonstrated that the ?FTT0918 strain contained a smaller free intracellular iron pool and that the ?fslA strain contained a larger one than SCHU S4. In contrast to the marked attenuation of the ?FTT0918 strain, the ?fslA strain was as virulent as SCHU S4 in a mouse model. Altogether, the data demonstrate that the FTT0918 protein is required for F. tularensis to utilize iron bound to siderophores and that it likely has a role also in siderophore-independent iron acquisition. We suggest that the FTT0918 protein be designated Fe utilization protein A, FupA. PMID:19651867

  10. Phase III Advanced Anodes and Cathodes Utilized in Energy Efficient Aluminum Production Cells

    SciTech Connect

    R.A. Christini; R.K. Dawless; S.P. Ray; D.A. Weirauch, Jr.

    2001-11-05

    During Phase I of the present program, Alcoa developed a commercial cell concept that has been estimated to save 30% of the energy required for aluminum smelting. Phase ii involved the construction of a pilot facility and operation of two pilots. Phase iii of the Advanced Anodes and Cathodes Program was aimed at bench experiments to permit the resolution of certain questions to be followed by three pilot cells. All of the milestones related to materials, in particular metal purity, were attained with distinct improvements over work in previous phases of the program. NiO additions to the ceramic phase and Ag additions to the Cu metal phase of the cermet improved corrosion resistance sufficiently that the bench scale pencil anodes met the purity milestones. Some excellent metal purity results have been obtained with anodes of the following composition: Further improvements in anode material composition appear to be dependent on a better understanding of oxide solubilities in molten cryolite. For that reason, work was commissioned with an outside consultant to model the MeO - cryolite systems. That work has led to a better understanding of which oxides can be used to substitute into the NiO-Fe2O3 ceramic phase to stabilize the ferrites and reduce their solubility in molten cryolite. An extensive number of vertical plate bench electrolysis cells were run to try to find conditions where high current efficiencies could be attained. TiB2-G plates were very inconsistent and led to poor wetting and drainage. Pure TiB2 did produce good current efficiencies at small overlaps (shadowing) between the anodes and cathodes. This bench work with vertical plate anodes and cathodes reinforced the importance of good cathode wetting to attain high current efficiencies. Because of those conclusions, new wetting work was commissioned and became a major component of the research during the third year of Phase III. While significant progress was made in several areas, much work needs to be done. The anode composition needs further improvements to attain commercial purity targets. At the present corrosion rate, the vertical plate anodes will wear too rapidly leading to a rapidly increasing anode-cathode gap and thermal instabilities in the cell. Cathode wetting as a function of both cathode plate composition and bath composition needs to be better understood to ensure that complete drainage of the molten aluminum off the plates occurs. Metal buildup appears to lead to back reaction and low current efficiencies.

  11. Determination of desorption efficiency utilizing direct injection: a dynamic calibration system and phase equilibrium 

    E-print Network

    Williams, Ronald H

    1979-01-01

    . The three methods involved a dynamic calibra- tion system, direct injection, and phase equilibrium. The methods differed in the manner in which the analyte was placed on the adsorbent. The desorption efficiencies ob- tained using the dynamic calibration... of this thesis helped make it a more complete work. Appreciation is expressed to Mr. R. A. Dommer of the Dow Chemical Company and Mr. R. J. Simmons of Texas AFM University for their aid and counsel dur'ing the develop- ment and analytical phases...

  12. High-Efficiency Extraction and Utilization of Lunar Solar Wind Volatiles

    NASA Astrophysics Data System (ADS)

    Petrick, David E.; Gardner, Tracy Q.; Nieczkoski, Steven J.

    2007-01-01

    A method of processing Lunar regolith for the extraction of solar wind volatiles has been developed to enable sustainable exploration of the Moon. The process incorporates efficient heat and mass transfer processes to provide thermal extraction and subsequent recovery of atoms implanted on the upper surface of Lunar regolith. End-to-end system modeling and component design establish a level feasibility and efficiency not previously achieved. Extracted molecular species are purified and stored on a mobile platform which delivers the resources to a central storage facility. The design concept results in several hundred times the mass of the facility produced in liquid product resources for life support and propulsion over the life of the system. Key developments include recuperative heating and cooling systems, rapid heating of regolith, and separation membranes capable of high selectivity due to thermal management. The ability to produce significant amounts of hydrogen, nitrogen, and helium from the Lunar surface will dramatically reduce the cost and complexity of performing ISRU with earth-based resources.

  13. Highly Carbonylated Cellulose Nanofibrous Membranes Utilizing Maleic Anhydride Grafting for Efficient Lysozyme Adsorption.

    PubMed

    Ma, Juncheng; Wang, Xueqin; Fu, Qiuxia; Si, Yang; Yu, Jianyong; Ding, Bin

    2015-07-22

    Construction of adsorptive materials for simple, efficient, and high-throughput adsorption of proteins is critical to meet the great demands of highly purified proteins in biotechnological and biopharmaceutical industry; however, it has proven extremely challenging. Here, we report a cost-effective strategy to create carbonyl groups surface-functionalized nanofibrous membranes under mild conditions for positively charged protein adsorption. Our approach allows maleic anhydride to in situ graft on cellulose nanofibrous membranes (CMA) to construct adsorptive membranes with large surface area and tortuous porous structure. Thereby, the resultant CMA membranes exhibited high adsorption capacity of 160 mg g(-1), fast equilibrium within 12 h, and good reversibility to lysozyme. Moreover, the dynamic adsorption was performed under low pressure-drops (750 Pa), with a relatively high saturation adsorption amount of 118 mg g(-1), which matched well with the requirements for proteins purification. Considering the excellent adsorption performance of the as-prepared adsorptive membranes, this simple and intriguing approach may pave a way for the design and development of robust and cost-effective adsorption membranes to meet the great demands for fast and efficient adsorption of positively charged proteins. PMID:26132415

  14. Energy-efficient reference gait generation utilizing variable ZMP and vertical hip motion based on inverted pendulum model for biped robots

    Microsoft Academic Search

    Hyeok Ki Shin; Byung Kook Kim

    2010-01-01

    Energy-efficient reference gait generation algorithm is suggested utilizing variable ZMP (Zero Moment Point) and vertical hip motion, which maxmizes the energy efficiency for cyclic gaits, based on inverted pendulum model (IPM) for biped robots. As observed in natural human walking, the robot's vertical hip motion (with average height and amplitude of hip ripple) as well as allowing variable ZMP pattern,

  15. Effects of experimental weight perturbation on skeletal muscle work efficiency, fuel utilization, and biochemistry in human subjects

    PubMed Central

    Goldsmith, Rochelle; Joanisse, Denis R.; Gallagher, Dympna; Pavlovich, Katherine; Shamoon, Elisabeth; Leibel, Rudolph L.

    2010-01-01

    Maintenance of a body weight 10% above or below that “customary” for lean or obese individuals results in respective increases or decreases in the energy expended in low levels of physical activity (nonresting energy expenditure, NREE). These changes are greater than can be accounted for by the altered body weight or composition and are due mainly to altered skeletal muscle work efficiency at low levels of power generation. We performed biochemical analysis of vastus lateralis muscle needle biopsy samples to determine whether maintenance of an altered body weight was associated with changes in skeletal muscle histomorphology. We found that the maintenance of a 10% reduced body weight was associated with significant declines in glycolytic (phosphofructokinase, PFK) enzyme activity and, in particular, in the ratio of glycolytic to oxidative (cytochrome c oxidase, COX) enzyme activity without significant changes in the activities of enzymes relevant to mitochondrial density, respiratory chain activity, or fuel transport; or in skeletal muscle fiber type or glycogen stores. The fractional change in the ratio of PFK/COX activity in subjects following weight loss was significantly correlated with changes in the systemic respiratory exchange ratio (RER) and measures of mechanical efficiency of skeletal muscle at low workloads (pedaling a bicycle to generate 10 or 25 W of power). Thus, predictable changes in systemic skeletal muscle biochemistry accompany the maintenance of an altered body weight and account for a significant portion of the variance in skeletal muscle work efficiency and fuel utilization at reduced body weight. PMID:19889869

  16. Utilization of a whole genome SNP panel for efficient genetic mapping in the mouse

    PubMed Central

    Moran, Jennifer L.; Bolton, Andrew D.; Tran, Pamela V.; Brown, Alison; Dwyer, Noelle D.; Manning, Danielle K.; Bjork, Bryan C.; Li, Cheng; Montgomery, Kate; Siepka, Sandra M.; Vitaterna, Martha Hotz; Takahashi, Joseph S.; Wiltshire, Tim; Kwiatkowski, David J.; Kucherlapati, Raju; Beier, David R.

    2006-01-01

    Phenotype-driven genetics can be used to create mouse models of human disease and birth defects. However, the utility of these mutant models is limited without identification of the causal gene. To facilitate genetic mapping, we developed a fixed single nucleotide polymorphism (SNP) panel of 394 SNPs as an alternative to analyses using simple sequence length polymorphism (SSLP) marker mapping. With the SNP panel, chromosomal locations for 22 monogenic mutants were identified. The average number of affected progeny genotyped for mapped monogenic mutations is nine. Map locations for several mutants have been obtained with as few as four affected progeny. The average size of genetic intervals obtained for these mutants is 43 Mb, with a range of 17–83 Mb. Thus, our SNP panel allows for identification of moderate resolution map position with small numbers of mice in a high-throughput manner. Importantly, the panel is suitable for mapping crosses from many inbred and wild-derived inbred strain combinations. The chromosomal localizations obtained with the SNP panel allow one to quickly distinguish between potentially novel loci or remutations in known genes, and facilitates fine mapping and positional cloning. By using this approach, we identified DNA sequence changes in two ethylnitrosourea-induced mutants. PMID:16461637

  17. Utilization of spent activated carbon to enhance the combustion efficiency of organic sludge derived fuel.

    PubMed

    Chen, Wei-Sheng; Lin, Chang-Wen; Chang, Fang-Chih; Lee, Wen-Jhy; Wu, Jhong-Lin

    2012-06-01

    This study examines the heating value and combustion efficiency of organic sludge derived fuel, spent activated carbon derived fuel, and derived fuel from a mixture of organic sludge and spent activated carbon. Spent activated carbon was sampled from an air pollution control device of an incinerator and characterized by XRD, XRF, TG/DTA, and SEM. The spent activated carbon was washed with deionized water and solvent (1N sulfuric acid) and then processed by the organic sludge derived fuel manufacturing process. After washing, the salt (chloride) and sulfide content could be reduced to 99% and 97%, respectively; in addition the carbon content and heating value were increased. Different ratios of spent activated carbon have been applied to the organic sludge derived fuel to reduce the NO(x) emission of the combustion. PMID:22209404

  18. Efficient Power Converters for PV Arrays : Scalable Submodule Power Conversion for Utility-Scale Photovoltaics

    SciTech Connect

    None

    2012-02-23

    Solar ADEPT Project: SolarBridge is developing a new power conversion technique to improve the energy output of PV power plants. This new technique is specifically aimed at large plants where many solar panels are connected together. SolarBridge is correcting for the inefficiencies that occur when two solar panels that encounter different amounts of sun are connected together. In most conventional PV system, the weakest panel limits the energy production of the entire system. That’s because all of the energy collected by the PV system feeds into a single collection point where a central inverter then converts it into useable energy for the grid. SolarBridge has found a more efficient and cost-effective way to convert solar energy, correcting these power differences before they reach the grid.

  19. Meta-analysis of factors that affect the utilization efficiency of phosphorus in lactating dairy cows.

    PubMed

    Klop, G; Ellis, J L; Bannink, A; Kebreab, E; France, J; Dijkstra, J

    2013-06-01

    A meta-analysis investigation based on literature data was conducted to estimate the effect size of nutritional and animal factors on phosphorus (P) excretion in feces and concentrations of P in milk. Two data sets were created for statistical analysis: One to derive prediction equations for P in feces (25 studies; 130 treatments) and another for P in milk (19 studies; 94 treatments). Prediction equations were derived using mixed model regression analysis with a random effect for study, and equations were evaluated based on values for Bayesian information criterion (BIC), root mean square prediction error (RMSPE), and concordance correlation coefficient (CCC) statistics. In terms of RMSPE and CCC values, fecal P excretion was best predicted by P intake, where P in feces (g/d)=-3.8(±3.45) + 0.64(±0.038) × P intake (g/d) (RMSPE: 18.3%, CCC: 0.869). However, significant effects of crude protein [g/kg of dry matter (DM)], neutral detergent fiber (g/kg of DM), and milk yield (kg/d) on fecal P excretion were also found. Despite a lack of improvement in terms of RMSPE and CCC values, these parameters may still explain part of the variation in fecal P excretion. For milk P, expressed as a fraction of P intake, the following equation had the highest CCC and the lowest RMSPE value: P in milk as a fraction of P intake (g/g)=0.42(±0.065) + 0.23(±0.018) × feed efficiency (i.e., fat- and protein-corrected milk yield/dry matter intake) - 0.11(±0.0199) × P in feed (g/kg of DM) (RMSPE: 19.7%; CCC: 0.761). Equations derived to predict fecal P as a fraction of P intake (g/g) or milk P content (g/kg) could not adequately explain the observed variation and did not perform well in terms of RMSPE and CCC values. Examination of the residuals showed that P balance was a seemingly confounding factor in some of the models. The results presented here can be used to estimate P in feces and milk based on commonly measured dietary and milk variables, but could also be used to guide development of mechanistic models on P metabolism in lactating dairy cattle. Factors to consider in future research and modeling efforts regarding efficiency of P use include the effects of dietary neutral detergent fiber, crude protein, starch, variation in P content of milk, and effects of P resorption from bone and body tissues during early lactation. PMID:23567051

  20. Adapting wave-front algorithms to efficiently utilize systems with deep communication hierarchies

    SciTech Connect

    Kerbyson, Darren J [Los Alamos National Laboratory; Lang, Michael [Los Alamos National Laboratory; Pakin, Scott [Los Alamos National Laboratory

    2009-01-01

    Large-scale systems increasingly exhibit a differential between intra-chip and inter-chip communication performance. Processor-cores on the same socket are able to communicate at lower latencies, and with higher bandwidths, than cores on different sockets either within the same node or between nodes. A key challenge is to efficiently use this communication hierarchy and hence optimize performance. We consider here the class of applications that contain wave-front processing. In these applications data can only be processed after their upstream neighbors have been processed. Similar dependencies result between processors in which communication is required to pass boundary data downstream and whose cost is typically impacted by the slowest communication channel in use. In this work we develop a novel hierarchical wave-front approach that reduces the use of slower communications in the hierarchy but at the cost of additional computation and higher use of on-chip communications. This tradeoff is explored using a performance model and an implementation on the Petascale Roadrunner system demonstrates a 27% performance improvement at full system-scale on a kernel application. The approach is generally applicable to large-scale multi-core and accelerated systems where a differential in system communication performance exists.

  1. Adapting Wave-front Algorithms to Efficiently Utilize Systems with Deep Communication Hierarchies

    SciTech Connect

    Kerbyson, Darren J.; Lang, Michael; Pakin, Scott

    2011-09-30

    Large-scale systems increasingly exhibit a differential between intra-chip and inter-chip communication performance especially in hybrid systems using accelerators. Processorcores on the same socket are able to communicate at lower latencies, and with higher bandwidths, than cores on different sockets either within the same node or between nodes. A key challenge is to efficiently use this communication hierarchy and hence optimize performance. We consider here the class of applications that contains wavefront processing. In these applications data can only be processed after their upstream neighbors have been processed. Similar dependencies result between processors in which communication is required to pass boundary data downstream and whose cost is typically impacted by the slowest communication channel in use. In this work we develop a novel hierarchical wave-front approach that reduces the use of slower communications in the hierarchy but at the cost of additional steps in the parallel computation and higher use of on-chip communications. This tradeoff is explored using a performance model. An implementation using the Reverse-acceleration programming model on the petascale Roadrunner system demonstrates a 27% performance improvement at full system-scale on a kernel application. The approach is generally applicable to large-scale multi-core and accelerated systems where a differential in system communication performance exists.

  2. Study on an Efficient Dehumidifying Air-conditioning System utilizing Phase Change of Intermediate Pressure Refrigerant

    NASA Astrophysics Data System (ADS)

    Maeda, Kensaku; Inaba, Hideo

    The present study has proven a new dehumidifying system that aimed to reduce the sensible heat factor(SHF) of cooling process without using additional heat to relieve the internationally indicated conflict between energy saving and dehumidification necessary for keeping adequate indoor air quality (IAQ). In this system, we used intermediate pressure refrigerant in a vapor compression refrigerating cycle as heat transfer medium of a characteristic heat exchanger to precool the process air entering into an evaporator as well as to reheat the process air leaving from the evaporator. By this system, the present results achieved higher moisture removal and consequently higher efficiency of dehumidifying process. In addition to this fact, since this system has capability of integration into air-conditioning apparatus(HVAC system), it will be able to work for wide range of cooling load by variable SHF function. In the present paper, technical information, experimental results, and simulation results which assumed to apply this system into HVAC system are reported.

  3. Long-duration high-efficiency operation of a continuously pulsed copper laser utilizing copper bromide as a lasant

    NASA Technical Reports Server (NTRS)

    Chen, C. J.; Bhanji, A. M.; Russell, G. R.

    1978-01-01

    A copper laser utilizing copper bromide as a lasant and neon as the buffer gas has been operated at an average laser power of between 16 and 19.5 W for a period of 68 h. Lasing was attained at a pulsing rate of 16.7 kHz in a quartz discharge tube 2.5-cm in diameter with an electrode separation of 200 cm. The laser energy/pulse and peak power/pulse corresponding to an average power of 19.5 W are 1.2 mJ and 30 kW, respectively. The ratio of laser power at 510.6 and 578.2 nm varied from 3.9 to 1.1 corresponding to a total average laser power of 4 and 18 W, respectively. The highest wall plug and capacitor efficiency measured during 68 h of operation were 0.7 and 1.1%, respectively.

  4. Reliable Open Spectrum Communications Through Proactive Spectrum Access

    E-print Network

    Madhow, Upamanyu

    1 Reliable Open Spectrum Communications Through Proactive Spectrum Access Prashanth Aravinda Kumar@cs.ucsb.edu Abstract-- Open Spectrum systems offer an attractive solution to the reuse of under-utilized licensed spectrum. Existing pro- posals take a reactive sense-and-avoid approach to impulsively reconfigure spectrum

  5. Partitioning of heat production in growing pigs as a tool to improve the determination of efficiency of energy utilization

    PubMed Central

    Labussière, Etienne; Dubois, Serge; van Milgen, Jaap; Noblet, Jean

    2013-01-01

    In growing pigs, the feed cost accounts for more than 60% of total production costs. The determination of efficiency of energy utilization through calorimetry measurements is of importance to sustain suitable feeding practice. The objective of this paper is to describe a methodology to correct daily heat production (HP) obtained from measurements in respiration chamber for the difference in energy expenditure related to physical activity between animals. The calculation is based on a preliminary published approach for partitioning HP between HP due to physical activity (AHP), thermic effect of feeding (TEF) and basal metabolic rate (fasting HP; FHP). Measurements with male growing pigs [mean body weight (BW): 115 kg] which were surgically castrated (SC), castrated through immunization against GnRH (IC), or kept as entire male (EM) were used as an example. Animals were fed the same diet ad-libitum and were housed individually in two 12-m3 open-circuit respiration chambers during 6 days when fed ad-libitum and one supplementary day when fasted. Physical activity was recorded through interruption of an infrared beam to detect standing and lying positions and with force transducers that recorded the mechanical force the animal exerted on the floor of the cage. Corrected AHP (AHPc), TEF (TEFc), and HP (HPc) were calculated to standardize the level of AHP between animals, assuming that the ratio between AHPc and ME intake should be constant. Inefficiency of energy utilization (sum of AHPc and TEFc) was lower than the inefficiency estimated from the slope of the classical relationship between HPc and ME intake but was associated with higher requirements for maintenance. Results indicate that EM pigs had higher FHP but lower TEFc than IC and SC pigs. These results agree with the higher contents in viscera of EM pigs that stimulate their basal metabolic rate and with the reduced utilization of dietary protein to provide energy for maintenance energy requirements and fat deposition (FD). PMID:23801965

  6. Building efficient comparative effectiveness trials through adaptive designs, utility functions, and accrual rate optimization: finding the sweet spot.

    PubMed

    Gajewski, Byron J; Berry, Scott M; Quintana, Melanie; Pasnoor, Mamatha; Dimachkie, Mazen; Herbelin, Laura; Barohn, Richard

    2015-03-30

    The time is right for the use of Bayesian Adaptive Designs (BAD) in comparative effectiveness trials. For example, Patient Centered Outcomes Research Institute has joined the Food and Drug Administration and National Intitutes of Health in adopting policies/guidelines encouraging their use. There are multiple aspects to BAD that need to be considered when designing a comparative effectiveness design. First, the adaptation rules can determine the expected size of the trial. Second, a utility function can be used to combine extremely important co-endpoints (e.g., efficacy and tolerability) and is a valuable tool for incorporating clinical expertise and potentially patient preference. Third, accrual rate is also very, very important. Specifically, there is a juxtaposition related to accrual and BAD. If accrual rate is too fast we never gain efficient information for adapting. If accrual rate is too slow we never finish the clinical trial. We propose methodology for finding the 'sweet spot' for BAD that addresses these as design parameters. We demonstrate the methodology on a comparative effectiveness BAD of pharmaceutical agents in cryptogenic sensory polyneuropathy. The study has five arms with two endpoints that are combined with a utility function. The accrual rate is assumed to stem from multiple sites. We perform simulations from which the composite accrual rates across sites result in various piecewise Poisson distributions as parameter inputs. We balance both average number of patients needed and average length of time to finish the study. PMID:25640114

  7. Pseudomonas putida strain PCL1444, selected for efficient root colonization and naphthalene degradation, effectively utilizes root exudate components.

    PubMed

    Kuiper, Irene; Kravchenko, Lev V; Bloemberg, Guido V; Lugtenberg, Ben J J

    2002-07-01

    Previously, we have described the selection of a plant-bacterium pair that is efficient in rhizoremediating naphthalene pollution in microcosm studies. After repeated selection for efficient root tip colonization upon inoculation of seeds of grass cv. Barmultra and for stable and efficient growth on naphthalene, Pseudomonas putida PCL1444 was selected as the most efficient colonizer of Barmultra roots. Here, we report the analysis of Barmultra root exudate composition and our subsequent tests of the growth rate of the bacterium and of the expression of the naphthalene degradation genes on individual exudate components. High performance liquid chromatography analysis of the organic acid and sugar root-exudate components revealed that glucose and fructose are the most abundant sugars, whereas succinic acid and citric acid are the most abundant organic acids. Tn5luxAB mutants of PCL1444 impaired in naphthalene degradation appeared to be impaired in genes homologous to genes of the upper naphthalene degradation pathway present in various Pseudomonas strains and to genes of the lower pathway genes for naphthalene degradation in P. stutzeri. Highest expression for both pathways involved in naphthalene degradation during growth in minimal medium with the carbon source to be tested was observed at the start of the logarithmic phase. Naphthalene did not induce the upper pathway, but a different pattern of expression was observed in the lower pathway reporter, probably due to the conversion of naphthalene to salicylic acid. Salicylic acid, which is described as an intermediate of the naphthalene degradation pathway in many Pseudomonas strains, did induce both pathways, resulting in an up to sixfold higher expression level at the start of the logarithmic phase. When expression levels during growth on the different carbon sources present in root exudate were compared, highest expression was observed on the two major root exudate components, glucose and succinic acid. These results show an excellent correlation between successful naphthalene rhizoremediation by the Barmultra-P. putida PCL1444 pair and both efficient utilization of the major exudate components for growth and high transcription of the naphthalene catabolic genes on the major exudate components. Therefore, we hypothesize that efficient root colonizing and naphthalene degradation is the result of the applied colonization enrichment procedure. PMID:12118890

  8. Numerical processing efficiency improved in children using mental abacus: ERP evidence utilizing a numerical Stroop task

    PubMed Central

    Yao, Yuan; Du, Fenglei; Wang, Chunjie; Liu, Yuqiu; Weng, Jian; Chen, Feiyan

    2015-01-01

    This study examined whether long-term abacus-based mental calculation (AMC) training improved numerical processing efficiency and at what stage of information processing the effect appeard. Thirty-three children participated in the study and were randomly assigned to two groups at primary school entry, matched for age, gender and IQ. All children went through the same curriculum except that the abacus group received a 2-h/per week AMC training, while the control group did traditional numerical practice for a similar amount of time. After a 2-year training, they were tested with a numerical Stroop task. Electroencephalographic (EEG) and event related potential (ERP) recording techniques were used to monitor the temporal dynamics during the task. Children were required to determine the numerical magnitude (NC) (NC task) or the physical size (PC task) of two numbers presented simultaneously. In the NC task, the AMC group showed faster response times but similar accuracy compared to the control group. In the PC task, the two groups exhibited the same speed and accuracy. The saliency of numerical information relative to physical information was greater in AMC group. With regards to ERP results, the AMC group displayed congruity effects both in the earlier (N1) and later (N2 and LPC (late positive component) time domain, while the control group only displayed congruity effects for LPC. In the left parietal region, LPC amplitudes were larger for the AMC than the control group. Individual differences for LPC amplitudes over left parietal area showed a positive correlation with RTs in the NC task in both congruent and neutral conditions. After controlling for the N2 amplitude, this correlation also became significant in the incongruent condition. Our results suggest that AMC training can strengthen the relationship between symbolic representation and numerical magnitude so that numerical information processing becomes quicker and automatic in AMC children. PMID:26042012

  9. Utilization of efficient gradient and Hessian computations in the force field optimization process of molecular simulations

    NASA Astrophysics Data System (ADS)

    Hülsmann, Marco; Kopp, Sonja; Huber, Markus; Reith, Dirk

    2013-01-01

    Computer simulations of chemical systems, especially systems of condensed matter, are highly important for both scientific and industrial applications. Thereby, molecular interactions are modeled on a microscopic level in order to study their impact on macroscopic phenomena. To be capable of predicting physical properties quantitatively, accurate molecular models are indispensable. Molecular interactions are described mathematically by force fields, which have to be parameterized. Recently, an automated gradient-based optimization procedure was published by the authors based on the minimization of a loss function between simulated and experimental physical properties. The applicability of gradient-based procedures is not trivial at all because of two reasons: firstly, simulation data are affected by statistical noise, and secondly, the molecular simulations required for the loss function evaluations are extremely time-consuming. Within the optimization process, gradients and Hessians were approximated by finite differences so that additional simulations for the respective modified parameter sets were required. Hence, a more efficient approach to computing gradients and Hessians is presented in this work. The method developed here is based on directional instead of partial derivatives. It is compared with the classical computations with respect to computation time. Firstly, molecular simulations are replaced by fit functions that define a functional dependence between specific physical observables and force field parameters. The goal of these simulated simulations is to assess the new methodology without much computational effort. Secondly, it is applied to real molecular simulations of the three chemical substances phosgene, methanol and ethylene oxide. It is shown that up to 75% of the simulations can be avoided using the new algorithm.

  10. Unmasking Novel Loci for Internal Phosphorus Utilization Efficiency in Rice Germplasm through Genome-Wide Association Analysis

    PubMed Central

    Wissuwa, Matthias; Kondo, Katsuhiko; Fukuda, Takuya; Mori, Asako; Rose, Michael T.; Pariasca-Tanaka, Juan; Kretzschmar, Tobias; Haefele, Stephan M.; Rose, Terry J.

    2015-01-01

    Depletion of non-renewable rock phosphate reserves and phosphorus (P) fertilizer price increases has renewed interest in breeding P-efficient varieties. Internal P utilization efficiency (PUE) is of prime interest because there has been no progress to date in breeding for high PUE. We characterized the genotypic variation for PUE present within the rice gene pool by using a hydroponic system that assured equal plant P uptake, followed by mapping of loci controlling PUE via Genome-Wide Association Studies (GWAS). Loci associated with PUE were mapped on chromosomes 1, 4, 11 and 12. The highest PUE was associated with a minor indica-specific haplotype on chromosome 1 and a rare aus-specific haplotype on chromosome 11. Comparative variant and expression analysis for genes contained within the chromosome 1 haplotype identified high priority candidate genes. Differences in coding regions and expression patterns between genotypes of contrasting haplotypes, suggested functional alterations for two predicted nucleic acid-interacting proteins that are likely causative for the observed differences in PUE. The loci reported here are the first identified for PUE in any crop that is not confounded by differential P uptake among genotypes. Importantly, modern rice varieties lacked haplotypes associated with superior PUE, and would thus benefit from targeted introgressions of these loci from traditional donors to improve plant growth in phosphorus-limited cropping systems. PMID:25923470

  11. Construction of a modular dihydrofolate reductase cDNA gene: Analysis of signals utilized for efficient expression

    SciTech Connect

    Kaufman, J.; Sharp, P.A.

    1982-11-01

    Dihydrofolate reductase (DHFR) modular genes have been constructed with segments containing the adenovirus major late promoter, a 3' splice site from a variable region immunoglobulin gene, a DHFR cDNA, and portions of the simian virus 40 (SV40) genome, DNA-mediated transfer of these genes transformed Chinese hamster ovary DHFR/sup -/ cells to the DHFR/sup +/ phenotype. Transformants contained one to several copies of the transfected DNA integrated into the host genome. Clones subjected to growth in increasing concentrations of methotrexate eventually gave rise to lines containing several hundred copies of the transforming DNA. Analysis of the DHFr mRNA produced in amplified lines indicated the following: (i) All clones utilize the adenovirus major late promoter for transcription initiation. (ii) A hybrid intron formed by the 5' splice site of the adenovirus major late leader and a 3' splice site from a variable-region immunoglobulin gene is properly excised. (iii) The mRNA is not efficiently polyadenylated at sequences in the 3' end of the DHFR cDNA but rather uses polyadenylation signals downstream from the DHFR cDNA. Three independent clones produce a DHFR mRNA containing SV40 or pBR322 and SV40 sequences, and the RNA is polyadenylated at the SV40 late polyadenylation site. Another clone has recombined into cellular DNA and apparently uses a cellular sequence for polyadenylation. Introduction of a segment containing the SV40 early polyadenylation signal into the 3' end of the DHFR cDNA generated a recombinant capable of transforming cells to the DHFR/sup +/ phenotype with at least a 10-fold increase in efficiency, demonstrating the necessity for an efficient polyadenylation signal. Attachment of a DNA segment containing the transcription enhancer 72-base pair repeat) of SV40 further increased the biological activity of the modular DHFR gene 50- to 100-fold.

  12. Utility of a Clinical Risk Factor Scoring Model in Predicting Infection with Extended-Spectrum ?-Lactamase-Producing Enterobacteriaceae on Hospital Admission

    PubMed Central

    Johnson, Steven W.; Anderson, Deverick J.; May, D. Byron; Drew, Richard H.

    2013-01-01

    OBJECTIVE To validate the utility of a previously published scoring model (Italian) to identify patients infected with community-onset extended-spectrum ?-lactamase-producing Enterobacteriaceae (ESBL-EKP) and develop a new model (Duke) based on local epidemiology. METHODS This case-control study included patients 18 years of age or more admitted to Duke University Hospital between January 1, 2008, and December 31, 2010, with culture-confirmed infection due to an ESBL-EKP (cases). Uninfected controls were matched to cases (3 : 1). The Italian model was applied to our patient population for validation. The Duke model was developed through logistic-regression-based prediction scores calculated on variables independently associated with ESBL-EKP isolation. Sensitivities and specificities at various point cutoffs were determined, and determination of the area under the receiver operating characteristic curve (ROC AUC) was performed. RESULTS A total of 123 cases and 375 controls were identified. Adjusted odds ratios and 95% confidence intervals for variables previously identified in the Italian model were as follows: hospitalization (3.20 [1.62–6.55]), transfer (4.31 [2.15–8.78]), urinary catheterization (5.92 [3.09–11.60]), ?-lactam and/or fluoroquinolone therapy (3.76 [2.06–6.95]), age 70 years or more (1.55 [0.79–3.01]), and Charlson Co-morbidity Score of 4 or above (1.06 [0.55–2.01]). Sensitivity and specificity were, respectively, more than or equal to 95% and less than or equal to 47% for scores 3 or below and were less than or equal to 50% and more than or equal to 96% for scores 8 or above. The ROC AUC was 0.88. Variables identified in the Duke model were as follows: hospitalization (2.63 [1.32–5.41]), transfer (5.30 [2.67–10.71]), urinary catheterization (6.89 [3.62–13.38]), ?-lactam and/or fluoroquinolone therapy (3.47 [1.91–6.41]), and immunosuppression (2.34 [1.14–4.80]). Sensitivity and specificity were, respectively, more than or equal to 94% and less than or equal to 65% for scores 3 or below and were less than or equal to 58% and more than or equal to 95% for scores 8 or above. The ROC AUC was 0.89. CONCLUSION While the previously reported model was an excellent predictor of community-onset ESBL-EKP infection, models utilizing factors based on local epidemiology may be associated with improved performance. PMID:23466912

  13. Signal, noise power spectrum, and detective quantum efficiency of indirect-detection flat-panel imagers for diagnostic radiology.

    PubMed

    Siewerdsen, J H; Antonuk, L E; el-Mohri, Y; Yorkston, J; Huang, W; Cunningham, I A

    1998-05-01

    The performance of an indirect-detection, active matrix flat-panel imager (FPI) at diagnostic energies is reported in terms of measured and theoretical signal size, noise power spectrum (NPS), and detective quantum efficiency (DQE). Based upon a 1536 x 1920 pixel, 127 microns pitch array of a-Si:H thin-film transistors and photodiodes, the FPI was developed as a prototype for examination of the potential of flat-panel technology in diagnostic x-ray imaging. The signal size per unit exposure (x-ray sensitivity) was measured for the FPI incorporating five commercially available Gd2O2S:Tb converting screens at energies 70-120 kVp. One-dimensional and two-dimensional NPS and DQE were measured for the FPI incorporating three such converters and as a function of the incident exposure. The measurements support the hypothesis that FPIs have significant potential for application in diagnostic radiology. A cascaded systems model that has shown good agreement with measured individual pixel signal and noise properties is employed to describe the performance of various FPI designs and configurations under a variety of diagnostic imaging conditions. Theoretical x-ray sensitivity, NPS, and DQE are compared to empirical results, and good agreement is observed in each case. The model is used to describe the potential performance of FPIs incorporating a recently developed, enhanced array that is commercially available and has been proposed for testing and application in diagnostic radiography and fluoroscopy. Under conditions corresponding to chest radiography, the analysis suggests that such systems can potentially meet or even exceed the DQE performance of existing technology, such as screen-film and storage phosphor systems; however, under conditions corresponding to general fluoroscopy, the typical exposure per frame is such that the DQE is limited by the total system gain and additive electronic noise. The cascaded systems analysis provides a valuable means of identifying the limiting stages of the imaging system, a tool for system optimization, and a guide for developing strategies of FPI design for various imaging applications. PMID:9608470

  14. Call admission control policies in cellular wireless networks with spectrum renting

    Microsoft Academic Search

    Show-Shiow Tzeng

    2009-01-01

    Radio spectrum is scarce and precious resource in wireless networks. To efficiently utilize radio spectrum, a wireless network can rent radio channels from another wireless network and returns back the rented channels when the rented channels are required to be withdrawn. The rental and withdrawal of radio channels result in two phenomena: (i) variable number of radio channels in a

  15. Route and Spectrum Selection in Dynamic Spectrum Networks

    E-print Network

    Almeroth, Kevin C.

    Route and Spectrum Selection in Dynamic Spectrum Networks Qiwei Wang Tsinghua University Beijing Barbara htzheng@cs.ucsb.edu Abstract-- Efficient spectrum allocation in dynamic spectrum systems and spectrum management makes it important to examine interaction between the two and the corresponding

  16. Efficiency of purine utilization by Helicobacter pylori: roles for adenosine deaminase and a NupC homolog.

    PubMed

    Miller, Erica F; Vaish, Soumya; Maier, Robert J

    2012-01-01

    The ability to synthesize and salvage purines is crucial for colonization by a variety of human bacterial pathogens. Helicobacter pylori colonizes the gastric epithelium of humans, yet its specific purine requirements are poorly understood, and the transport mechanisms underlying purine uptake remain unknown. Using a fully defined synthetic growth medium, we determined that H. pylori 26695 possesses a complete salvage pathway that allows for growth on any biological purine nucleobase or nucleoside with the exception of xanthosine. Doubling times in this medium varied between 7 and 14 hours depending on the purine source, with hypoxanthine, inosine and adenosine representing the purines utilized most efficiently for growth. The ability to grow on adenine or adenosine was studied using enzyme assays, revealing deamination of adenosine but not adenine by H. pylori 26695 cell lysates. Using mutant analysis we show that a strain lacking the gene encoding a NupC homolog (HP1180) was growth-retarded in a defined medium supplemented with certain purines. This strain was attenuated for uptake of radiolabeled adenosine, guanosine, and inosine, showing a role for this transporter in uptake of purine nucleosides. Deletion of the GMP biosynthesis gene guaA had no discernible effect on mouse stomach colonization, in contrast to findings in numerous bacterial pathogens. In this study we define a more comprehensive model for purine acquisition and salvage in H. pylori that includes purine uptake by a NupC homolog and catabolism of adenosine via adenosine deaminase. PMID:22701700

  17. Free lysine ( l-lysine · HCl) is utilized for growth less efficiently than protein-bound lysine (soybean meal) in practical diets by young channel catfish ( Ictalurus punctatus)

    Microsoft Academic Search

    Dannie D. Zarate; Richard T. Lovell

    1997-01-01

    Two 10-week feeding experiments were conducted with channel catfish fingerlings in aquaria to compare the efficiency of utilization for growth of free versus protein bound lysine in practical diets. In experiment 1, a basal, 26% protein diet, deficient only in lysine, was formulated with a combination of peanut meal and corn gluten meal as the primary protein source. The diet

  18. Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms

    NASA Astrophysics Data System (ADS)

    Shi, Jianyang; Zhang, Junwen; Tao, Li; Wang, Yiguang; Wang, Yuanquan; Chi, Nan

    2014-07-01

    Quadrature duobinary (QDB) spectrum shaping polarization division multiplexed-quadrature phase shift keying (PDM-QPSK) signal with Nyquist and super-Nyquist spectrum efficiency will be a promising candidate for future ultrahigh speed ultrahigh spectrum efficiency coherent optical fiber transmissions systems. Several equalization algorithms including constant modulus algorithm (CMA), CMA plus postfilter, and cascaded multimodulus algorithm (CMMA) have been proposed as effective solutions for QDB-PDM-QPSK signal. For the first time as far as we know, the application conditions and performances for these three algorithms are analyzed and compared. System performances for a 112-Gb/s QDB-PDM-QPSK signal as a function of the optical filtering bandwidth and the optical SNR have been theoretically investigated. The results show that CMA would be the best choice in terms of convergence rate for general filtering. However, CMMA can outperform the other two schemes with a good receiver sensitivity and high-dynamic range of optical signal to noise ratio giving a strong filtering effect of super-Nyquist signaling.

  19. MINING SPECTRUM USAGE DATA: A LARGE-SCALE SPECTRUM MEASUREMENT

    E-print Network

    Liu, Mingyan

    1 MINING SPECTRUM USAGE DATA: A LARGE-SCALE SPECTRUM MEASUREMENT STUDY Sixing Yin , Dawei Chen,qianzh}@cse.ust.hk University of Michigan mingyan@eecs.umich.edu November 19, 2009 DRAFT #12;Abstract Dynamic spectrum access calls for a deeper understanding of the characteristics of current spectrum utilization. In this paper

  20. Efficient ultrashort-pulse generation of Yb:YAG laser overcoming the fluorescence spectrum limit by using nonlinear medium

    Microsoft Academic Search

    S. Matsubara; M. Takama; M. Inoue; S. Kawato; Y. Ishida

    2008-01-01

    One-hundred-ten-fs and 72-fs pulse-widths were obtained directly from a mode-locked Yb:YAG laser with SESAM and without SESAM, respectively. The laser-spectrum-center and the fluorescence-center were almost same. The oscillation-spectra were much broader than the fluorescence.

  1. Efficient use of pseudo-noise sequences in synchronous direct-sequence spread-spectrum multiple-access communication systems

    Microsoft Academic Search

    Chi-Kin Chan; Wong-Hing Lam

    1994-01-01

    In this paper, four different spreading schemes have been employed in a synchronous direct-sequence spread-spectrum multiple-access systems (S-DS\\/SSMA) over a Gaussian channel. These include different sets of pseudo-noise (PN) sequences, composite sequences, bit-scrambling on PN sequences and PN sequences as error-correction coding. The bit-error-rate (BER) performance of these schemes showed that the orthogonal sets of sequences is optimal for S-DS\\/SSMA

  2. Realizing high photovoltaic efficiency with parallel multijunction solar cells based on spectrum-splitting and -concentrating diffractive optical element

    NASA Astrophysics Data System (ADS)

    Wang, Jin-Ze; Huang, Qing-Li; Xu, Xin; Quan, Bao-Gang; Luo, Jian-Heng; Zhang, Yan; Ye, Jia-Sheng; Li, Dong-Mei; Meng, Qing-Bo; Yang, Guo-Zhen

    2015-05-01

    Based on the facts that multijunction solar cells can increase the efficiency and concentration can reduce the cost dramatically, a special design of parallel multijunction solar cells was presented. The design employed a diffractive optical element (DOE) to split and concentrate the sunlight. A rainbow region and a zero-order diffraction region were generated on the output plane where solar cells with corresponding band gaps were placed. An analytical expression of the light intensity distribution on the output plane of the special DOE was deduced, and the limiting photovoltaic efficiency of such parallel multijunction solar cells was obtained based on Shockley–Queisser’s theory. An efficiency exceeding the Shockley–Queisser limit (33%) can be expected using multijunction solar cells consisting of separately fabricated subcells. The results provide an important alternative approach to realize high photovoltaic efficiency without the need for expensive epitaxial technology widely used in tandem solar cells, thus stimulating the research and application of high efficiency and low cost solar cells. Project supported by the National Natural Science Foundation of China (Grant Nos. 91233202, 21173260, and 51072221) and the National Basic Research Program of China (Grant No. 2012CB932903).

  3. Report of Energy Efficiency Study and Metering/Utilities Profile for Electricity Deregulation at Texas A&M University – Texarkana (TAMU–T) Texarkana, Texas 

    E-print Network

    Zhu, Y.; Turner, W. D.; Claridge, D. E.

    1999-01-01

    System Submitted by Yeqiao Zhu Dan Turner David Claridge Energy Systems Laboratory The Texas A&M University System December, 1999 Acknowledgement The Electric Utility Regulation and Energy Efficiency Study for all universities in the TAMU System... was initiated in May 1999 and is funded through an interagency agreement between the Chancellor's office and TEES's Energy Systems Laboratory. Detailed site visits were made to all system universities throughout the summer and fall. The Energy Systems Laboratory...

  4. Report of Energy Efficiency Study and Metering/Utilities Profile for Electricity Deregulation at Texas A&M University – Commerce (TAMU–C) Commerce, Texas

    E-print Network

    Wei, G.; Campbell, C.; Claridge, D. E.; Turner, W. D.

    1999-01-01

    AHUs in this building. They used to be multi-zone units and were retrofitted to VAV systems later on by blocking the heating coils and installing VAV 2 reheat boxes at individual zones. However, no control valves were installed at the cooling coil...&M University System Submitted by Guanghua Wei Craig Campbell David Claridge Dan Turner Energy Systems Laboratory The Texas A&M University System December, 1999 Acknowledgement The Electric Utility Regulation and Energy Efficiency Study for all universities...

  5. Utility of the "Social Communication Questionnaire-Current" and "Social Responsiveness Scale" as Teacher-Report Screening Tools for Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Schanding, G. Thomas, Jr.; Nowell, Kerri P.; Goin-Kochel, Robin P.

    2012-01-01

    Limited research exists regarding the role of teachers in screening for Autism Spectrum Disorders (ASD). The current study examined the use of the "Social Communication Questionnaire" (SCQ) and "Social Responsiveness Scale" (SRS) as completed by parents and teachers about school-age children from the Simons Simplex Collection. Using the…

  6. Improved light extraction efficiency with angle independent electroluminescence spectrum in nano-phosphor coated white organic light emitting diodes

    Microsoft Academic Search

    Arunandan Kumar; Ritu Srivastava; Priyanka Tyagi; D. S. Mehta; M. N. Kamalasanan

    2011-01-01

    We have fabricated down converted white organic light emitting diodes (WOLEDs) by using cerium doped YAG nano-phosphor after mixing them in binder poly venyle acetate (PVAc) polymer matrix by changing the concentration of nano-phosphor. Down conversion layer was deposited by using a low cost spin coating technique. The enhancement in extraction efficiency by a factor of about 1.6 was found

  7. About efficiency of identification of materials using spectrum dynamics of medium response under the action of THz radiation

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Varentsova, Svetlana A.

    2009-05-01

    A method, suggested by us earlier for identification of materials with close spectra in terahertz range of frequencies and based on the analysis of medium response spectral lines dynamics, is verified experimentally. The temporal dynamics of spectral lines allows to determine relaxation time of rotational transitions as well. A question about measurement time, that is sufficient for determining of material response characteristic time, is discussed. To demonstrate the efficiency of proposed method, we treat the response of soap and chocolate under the action of terahertz pulse with a few cycles. Our investigation shows that it is possible to identify these materials with high probability.

  8. Monitoring the performance of solar heated and cooled buildings. Volume 1. Data acquisition equipment for the spectrum of electric utility projects. Final report

    Microsoft Academic Search

    1979-01-01

    Electric utility projects to monitor the performance of solar heated or cooled buildings are reviewed. The range and nature of the systems monitored, the variables measured, and the monitoring equipment employed are discussed. The experiences and views of project personnel are also discussed. Based on this picture of performance monitoring activity, five classes of data acquisition are identified and described:

  9. SAVING MONEY & TIME (EFFICIENCY) UTILITY COST AVOIDANCE: From FY 2001 through FY2012, the UW Seattle campus has avoided

    E-print Network

    Van Volkenburgh, Elizabeth

    and programs. http://www.washington.edu/facilities/conserve/measures. Contact: Jim Angelosante, Director.pdf Contact: Emily Newcomer, Manager Program Operations, Recycling & Solid Waste, emilyn2@uw.edu MAINTENANCE Seattle campus has avoided a cumulative $95.1 million in utility costs through its conservation efforts

  10. CLUSTERING OF LEGISLATIVE SECURITY OF CAR UTILIZATION IN ASPECT OF EFFICIENCY OF PERFORMANCE OF NATIONAL ADMINISTRATIVE AGENCIES IN POLAND

    Microsoft Academic Search

    Zbigniew Burski

    Summary. The paper discusses the issue of clustering of legislative security of car utilization in aspect of effi ciency of performance of national administrative agencies in Poland. The issue of security in exploitation of vehicles and working machines is one of the most important system problems in contemporary scientifi c re- searches. Government and ownership transitions in the country caused

  11. Resource utilization efficiency improvement of geothermal binary cycles, phase I. Semiannual progress report, June 15, 1975December 15, 1975

    Microsoft Academic Search

    K. E. Starling; L. W. Fish; K. Z. Iqbal; D. Yieh

    1975-01-01

    A summary of the research carried out prior to the start and during the first half of this project is presented. A description of the geothermal binary cycle and procedures for cycle thermodynamic analysis focusing on the question of resource utilization are discussed. General and specific criteria for preliminary selection of working fluids and operating conditions for binary cycles are

  12. Substrate characterization for underwater gamma spectrometry: tank measurement results utilizing efficiencies calculated via Monte-Carlo code

    Microsoft Academic Search

    R. Ocone; A. Kostezh; V. Kurinenko; A. Tyshchenko; G. Derkach; P. Leone

    2004-01-01

    In order to study the sediment contamination, underwater gamma-ray spectrometry measurements performed by the sub-marine detector Canberra HpGe with a relative efficiency of 80% were carried out in an equipped tank at the Ukrainian Hydrometeorological Institute of Kiev. Different substrates, certified sources and experiment geometrical set-up were arranged. Efficiencies were calculated by in situ object counting system (ISOCS) software. ISOCS

  13. Efficient utilization of greenhouse gases in a gas-to-liquids process combined with CO2/steam-mixed reforming and Fe-based Fischer-Tropsch synthesis.

    PubMed

    Zhang, Chundong; Jun, Ki-Won; Ha, Kyoung-Su; Lee, Yun-Jo; Kang, Seok Chang

    2014-07-15

    Two process models for carbon dioxide utilized gas-to-liquids (GTL) process (CUGP) mainly producing light olefins and Fischer-Tropsch (F-T) synthetic oils were developed by Aspen Plus software. Both models are mainly composed of a reforming unit, an F-T synthesis unit and a recycle unit, while the main difference is the feeding point of fresh CO2. In the reforming unit, CO2 reforming and steam reforming of methane are combined together to produce syngas in flexible composition. Meanwhile, CO2 hydrogenation is conducted via reverse water gas shift on the Fe-based catalysts in the F-T synthesis unit to produce hydrocarbons. After F-T synthesis, the unreacted syngas is recycled to F-T synthesis and reforming units to enhance process efficiency. From the simulation results, it was found that the carbon efficiencies of both CUGP options were successfully improved, and total CO2 emissions were significantly reduced, compared with the conventional GTL processes. The process efficiency was sensitive to recycle ratio and more recycle seemed to be beneficial for improving process efficiency and reducing CO2 emission. However, the process efficiency was rather insensitive to split ratio (recycle to reforming unit/total recycle), and the optimum split ratio was determined to be zero. PMID:24933030

  14. Efficient AntiCollision Algorithm Utilizing the Capture Effect for ISO 18000-6C RFID Protocol

    Microsoft Academic Search

    Bo Li; Junyu Wang

    2011-01-01

    The capture effect commonly occurs when multiple tags simultaneously transmit their signals in ISO 18000-6C RFID systems, introducing challenges and opportunities for access con- trol method design. In this letter, a novel anti-collision algorithm utilizing the capture effect for ISO 18000-6C protocol is presented based on the design of the capture-aware backlog estimation method and the derivation of the capture-aware

  15. Improving the Combustion Performance of a 660MWe Down-Fired Utility Boiler by Adopting High Efficiency Combustion Technologies

    Microsoft Academic Search

    Zhengqi Li; Guangkui Liu; Qunyi Zhu; Zhichao Chen; Feng Ren

    2011-01-01

    To overcome the problem of high carbon content in the fly ash of down-fired utility boilers using low-volatility coals, the combustion system of a 660 MWe full-scale down-fired boiler was retrofitted with many items: louver concentrators was adopted, the fuel-lean flow is laid near the wall, the F-tier secondary air is modified with an angle of declination of 20°. Industrial

  16. Substrate characterization for underwater gamma spectrometry: tank measurement results utilizing efficiencies calculated via Monte-Carlo code.

    PubMed

    Ocone, R; Kostezh, A; Kurinenko, V; Tyshchenko, A; Derkach, G; Leone, P

    2004-01-01

    In order to study the sediment contamination, underwater gamma-ray spectrometry measurements performed by the sub-marine detector Canberra HpGe with a relative efficiency of 80% were carried out in an equipped tank at the Ukrainian Hydrometeorological Institute of Kiev. Different substrates, certified sources and experiment geometrical set-up were arranged. Efficiencies were calculated by in situ object counting system (ISOCS) software. ISOCS performance tests using certified sources were carried out by comparing laboratory measurements, and measurement results for mineralogy and density performances are reported. PMID:15177333

  17. Gas-turbine engines with increased efficiency of two circuits, due to the use of the utilizing steam-turbine circuit

    NASA Astrophysics Data System (ADS)

    Emin, O. N.; Kuznetsov, V. I.

    1994-01-01

    The possibility of significantly increasing the efficiency of the two circuits of a turbojet engine is justified. It is assumed that for this purpose the power of an additional steam turbine will be used, when utilizing heat of exhaust gases in the internal circuit of the gas-turbine engine. The main equations describing the working process have been derived. The parameters of the steam-turbine circuit have been assessed. Calculations for an engine with a thrust of 45-50 t for an aircraft, accommodating 500-800 persons, have been made.

  18. Efficient utilization of on-chip inductors in silicon RF IC design using a novel CAD tool; the LNA paradigm

    Microsoft Academic Search

    Yannis Papananos; Yorgos Koutsoyannopoulos

    1998-01-01

    A CAD tool for modelling planar and multi-layer polygonal integrated inductors on silicon substrates has been developed. The tool can be used in the efficient design of RF ICs containing on-chip inductors. The accuracy and reliability of the software is established through measurement results. The CAD tool is then used in the extraction of design guidelines for the development of

  19. Executive Summary The utilization of a digital content delivery network can be key to site performance and efficiency.

    E-print Network

    Fisher, Kathleen

    performance and efficiency. Yet performance also hinges on many other factors. In planning and implementing chain" required to deliver high performance and an engaging experience. The distribution of digital, enterprises far from the media world are using digital media for organizational communication, employee

  20. Zellweger Spectrum

    MedlinePLUS

    ... of severity of disease. What causes the Zellweger spectrum of diseases? As we mentioned, disorders of the ... What are the clinical symptoms of the Zellweger spectrum of diseases? The disorders of the Zellweger spectrum ...

  1. Efficient biological conversion of carbon monoxide (CO) to carbon dioxide (CO2) and for utilization in bioplastic production by Ralstonia eutropha through the display of an enzyme complex on the cell surface.

    PubMed

    Hyeon, Jeong Eun; Kim, Seung Wook; Park, Chulhwan; Han, Sung Ok

    2015-06-01

    An enzyme complex for biological conversion of CO to CO2 was anchored on the cell surface of the CO2-utilizing Ralstonia eutropha and successfully resulted in a 3.3-fold increase in conversion efficiency. These results suggest that this complexed system may be a promising strategy for CO2 utilization as a biological tool for the production of bioplastics. PMID:26017299

  2. Utility and efficiency of linked marker genes for genetic counseling. III. Proportion of informative families under linkage disequilibrium.

    PubMed Central

    Chakravarti, A

    1983-01-01

    A marker locus closely linked to a disease locus is often useful for genetic counseling provided that a counselee is heterozygous at both disease and marker loci. Furthermore, the linkage phase of these genes in the counselee must be known. When the linkage between the disease and marker loci is very close, one often finds linkage disequilibrium between the loci. To evaluate the effect of such nonrandom associations on the utility of linked marker genes for genetic counseling, the proportion of informative families is studied for X-linked recessive and autosomal dominant diseases. This proportion is higher for X-linked genes than for autosomal genes, if other factors are the same. In general, codominant markers are more useful than dominant markers. Also, under appropriate conditions, the proportion of informative families is higher when linkage disequilibrium is present. The results obtained in this paper are useful for evaluating the utility of polymorphic restriction endonuclease cleavage sites as markers in genetic counseling. PMID:6576632

  3. Efficient utilization of complex N-linked glycans is a selective advantage for Bacteroides fragilis in extraintestinal infections.

    PubMed

    Cao, Yanlu; Rocha, Edson R; Smith, C Jeffrey

    2014-09-01

    Bacteroides fragilis is the most common anaerobe isolated from clinical infections, and in this report we demonstrate a characteristic of the species that is critical to their success as an opportunistic pathogen. Among the Bacteroides spp. in the gut, B. fragilis has the unique ability of efficiently harvesting complex N-linked glycans from the glycoproteins common to serum and serous fluid. This activity is mediated by an outer membrane protein complex designated as Don. Using the abundant serum glycoprotein transferrin as a model, it has been shown that B. fragilis alone can rapidly and efficiently deglycosylate this protein in vitro and that transferrin glycans can provide the sole source of carbon and energy for growth in defined media. We then showed that transferrin deglycosylation occurs in vivo when B. fragilis is propagated in the rat tissue cage model of extraintestinal growth, and that this ability provides a competitive advantage in vivo over strains lacking the don locus. PMID:25139987

  4. Efficient utilization of complex N-linked glycans is a selective advantage for Bacteroides fragilis in extraintestinal infections

    PubMed Central

    Cao, Yanlu; Rocha, Edson R.; Smith, C. Jeffrey

    2014-01-01

    Bacteroides fragilis is the most common anaerobe isolated from clinical infections, and in this report we demonstrate a characteristic of the species that is critical to their success as an opportunistic pathogen. Among the Bacteroides spp. in the gut, B. fragilis has the unique ability of efficiently harvesting complex N-linked glycans from the glycoproteins common to serum and serous fluid. This activity is mediated by an outer membrane protein complex designated as Don. Using the abundant serum glycoprotein transferrin as a model, it has been shown that B. fragilis alone can rapidly and efficiently deglycosylate this protein in vitro and that transferrin glycans can provide the sole source of carbon and energy for growth in defined media. We then showed that transferrin deglycosylation occurs in vivo when B. fragilis is propagated in the rat tissue cage model of extraintestinal growth, and that this ability provides a competitive advantage in vivo over strains lacking the don locus. PMID:25139987

  5. BRIEF COMMUNICATIONS: Efficiency of lasers utilizing vapors of complex organic compounds subjected to hard ultraviolet (266 nm) pumping

    Microsoft Academic Search

    A. P. Ermachenok; O. A. Logunov; Aleksandr V. Startsev; Yu Yu Stoilov

    1983-01-01

    Measurements were made of the efficiency of stimulated emission in the range 329-400 and 500 nm by a series of complex organic compounds in gaseous mixtures with pentane (1.5×1021cm-3) when the vapor was excited by the fourth harmonic of neodymium laser radiation (266 nm, 5 nsec, 20 mJ). Lasing of PPD (340 nm) and PBD (352 nm) vapors was observed

  6. Evaluation of Characteristics of High Efficiency Power Generation Systems Utilizing Fermentation Gas of Simply Sorted Municipal Refuse

    NASA Astrophysics Data System (ADS)

    Pak, Pyong Sik

    This paper evaluates characteristics of two kinds of power generation systems utilizing fermentation gas of municipal refuse which is generated with use of a fermentation equipment of sorted refuse from ordinary collected garbage. In evaluation, a garbage incineration plant treating refuse of 100 t/d was adopted. The two systems investigated are the following systems: (a) gas engine power generation system (Sys-GE) and (b) steam turbine power generation system with super heater of steam (Sys-SH). The characteristics of two systems have been estimated together with the conventional steam turbine power generation system (Sys-C). It has been estimated that Sys-GE and Sys-SH has 2.11 and 2.55 times greater energy saving and CO2 reduction effect compared with Sys-C, respectively.

  7. The enhancement of 21.2%-power conversion efficiency in polymer photovoltaic cells by using mixed Au nanoparticles with a wide absorption spectrum of 400 nm–1000 nm

    NASA Astrophysics Data System (ADS)

    Hao, Jing-Yu; Xu, Ying; Zhang, Yu-Pei; Chen, Shu-Fen; Li, Xing-Ao; Wang, Lian-Hui; Huang, Wei

    2015-04-01

    Au nanoparticles (NPs) mixed with a majority of bone-like, rod, and cube shapes and a minority of irregular spheres, which can generate a wide absorption spectrum of 400 nm–1000 nm and three localized surface plasmon resonance peaks, respectively, at 525, 575, and 775 nm, are introduced into the hole extraction layer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) to improve optical-to-electrical conversion performances in polymer photovoltaic cells. With the doping concentration of Au NPs optimized, the cell performance is significantly improved: the short-circuit current density and power conversion efficiency of the poly(3-hexylthiophene): [6,6]-phenyl-C60-butyric acid methyl ester cell are increased by 20.54% and 21.2%, reaching 11.15 mA·cm?2 and 4.23%. The variations of optical, electrical, and morphology with the incorporation of Au NPs in the cells are analyzed in detail, and our results demonstrate that the cell performance improvement can be attributed to a synergistic reaction, including: 1) both the localized surface plasmon resonance- and scattering-induced absorption enhancement of the active layer, 2) Au doping-induced hole transport/extraction ability enhancement, and 3) large interface roughness-induced efficient exciton dissociation and hole collection. Project supported by the National Basic Research Program of China (Grant Nos. 2015CB932202 and 2012CB933301), the National Natural Science Foundation of China (Grant Nos. 61274065, 51173081, 61136003, BZ2010043, 51372119, and 51172110), the Science Fund from the Ministry of Education of China (Grant No. IRT1148), the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20113223110005), the Priority Academic Program Development of Jiangsu Provincial Higher Education Institutions (Grant No. YX03001), and the National Synergistic Innovation Center for Advanced Materials and the Synergetic Innovation Center for Organic Electronics and Information Displays, China.

  8. HIGH EFFICIENCY, QUASI-INSTANTANEOUS STEAM EXPANSION DEVICE UTILIZING FOSSIL OR NUCLEAR FUEL AS THE HEAT SOURCE

    SciTech Connect

    Claudio Filippone, Ph.D.

    1999-06-01

    Thermal-hydraulic analysis of a specially designed steam expansion device (heat cavity) was performed to prove the feasibility of steam expansions at elevated rates for power generation with higher efficiency. The steam expansion process inside the heat cavity greatly depends on the gap within which the steam expands and accelerates. This system can be seen as a miniaturized boiler integrated inside the expander where steam (or the proper fluid) is generated almost instantaneously prior to its expansion in the work-producing unit. Relatively cold water is pulsed inside the heat cavity, where the heat transferred causes the water to flash to steam, thereby increasing its specific volume by a large factor. The gap inside the heat cavity forms a special nozzle-shaped system in which the fluid expands rapidly, accelerating toward the system outlet. The expansion phenomenon is the cause of ever-increasing fluid speed inside the cavity system, eliminating the need for moving parts (pumps, valves, etc.). In fact, the subsequent velocity induced by the sudden fluid expansion causes turbulent conditions, forcing accelerating Reynolds and Nusselt numbers which, in turn, increase the convective heat transfer coefficient. When the combustion of fossil fuels constitutes the heat source, the heat cavity concept can be applied directly inside the stator of conventional turbines, thereby greatly increasing the overall system efficiency.

  9. Opportunistic Spectrum Access for Mobile Cognitive Radios

    E-print Network

    Shihada, Basem

    Opportunistic Spectrum Access for Mobile Cognitive Radios Alexander W. Min, Kyu-Han Kim,§ Jatinder spectrum scarcity problem by utilizing their capability of ac- cessing licensed spectrum bands opportunistically. While most existing work focuses on enabling such opportunistic spectrum access for stationary

  10. Module greenhouse with high efficiency of transformation of solar energy, utilizing active and passive glass optical rasters

    SciTech Connect

    Korecko, J.; Jirka, V. [ENKI, o.p.s., Dukelska 145, 379 01 Trebon (Czech Republic); Sourek, B. [ENKI, o.p.s., Dukelska 145, 379 01 Trebon (Czech Republic); Czech Technical University of Prague, Technicka 4, 166 07 Prague (Czech Republic); Cerveny, J. [ENKI, o.p.s., Dukelska 145, 379 01 Trebon (Czech Republic); Institute of Physical Biology, Zamek 136, 373 33 Nove Hrady (Czech Republic)

    2010-10-15

    Since the eighties of the 20th century, various types of linear glass rasters for architectural usage have been developed in the Czech Republic made by the continuous melting technology. The development was focused on two main groups of rasters - active rasters with linear Fresnel lenses in fixed installation and with movable photo-thermal and/or photo-thermal/photo-voltaic absorbers. The second group are passive rasters based on total reflection of rays on an optical prism. During the last years we have been working on their standardization, exact measuring of their optical and thermal-technical characteristics and on creation of a final product that could be applied in solar architecture. With the project supported by the Ministry of Environment of the Czech Republic we were able to build an experimental greenhouse using these active and passive optical glass rasters. The project followed the growing number of technical objectives. The concept of the greenhouse consisted of interdependence construction - structural design of the greenhouse with its technological equipment securing the required temperature and humidity conditions in the interior of the greenhouse. This article aims to show the merits of the proposed scheme and presents the results of the mathematical model in the TRNSYS environment through which we could predict the future energy balance carried out similar works, thus optimizing the investment and operating costs. In this article description of various technology applications for passive and active utilization of solar radiation is presented, as well as some results of short-term and long-term experiments, including evaluation of 1-year operation of the greenhouse from the energy and interior temperature viewpoints. A comparison of the calculated energy flows in the greenhouse to real measured values, for verification of the installed model is also involved. (author)

  11. Utility and efficiency of linked marker genes for genetic counseling. II. Identification of linkage phase by offspring phenotypes

    PubMed Central

    Chakravarti, Aravinda; Nei, Masatoshi

    1982-01-01

    For a linked marker locus to be useful for genetic counseling, the counselee must be heterozygous for both disease and marker loci and his or her linkage phase must be known. It is shown that when the phenotypes of the counselee's previous children for the disease and marker loci are known, the linkage phase can often be inferred with a high probability, and thus it is possible to conduct genetic counseling. To evaluate the utility of linked marker genes for genetic counseling, the accuracy of prediction of the risk for a prospective child with a given marker gene to develop the genetic disease and the proportion of families in which a particular marker locus can be used for genetic counseling are studied for X-linked recessive, autosomal dominant, and autosomal recessive diseases. In the case of X-linked genetic diseases, information from children is very useful for determining the linkage phase of the counselee and predicting the genetic disease. In the case of autosomal dominant diseases, not all children are informative, but if the number of children is large, the phenotypes of children are often more informative than the information from grandparents. In the case of autosomal recessive diseases, information from grandparents is usually useless, since they show a normal phenotype for the disease locus. If we use information on the phenotypes of children, however, the linkage phase of the counselee and the risk of a prospective child can be inferred with a high probability. The proportion of informative families depends on the dominance relationship and frequencies of marker alleles, and the number of children. In general, codominant markers are more useful than are dominant markers, and a locus with high heterozygosity is more useful than is a locus with low heterozygosity. PMID:6954847

  12. Hijack it, change it: how do plant viruses utilize the host secretory pathway for efficient viral replication and spread?

    PubMed Central

    Patarroyo, Camilo; Laliberté, Jean-François; Zheng, Huanquan

    2013-01-01

    The secretory pathway of eukaryotic cells has an elaborated set of endomembrane compartments involved in the synthesis, modification, and sorting of proteins and lipids. The secretory pathway in plant cells shares many features with that in other eukaryotic cells but also has distinct characteristics important for fundamental cell and developmental processes and for proper immune responses. Recently, there has been evidence that the remodeling of this pathway, and often the formation of viral-induced organelles, play an important role in viral replication and spread. The modification of the host secretory pathway seems to be a common feature among most single-stranded positive ss(+)RNA and even some DNA viruses. In this review, we will present the recent advances in the understanding of the organization and dynamics of the plant secretory pathway and the molecular regulation of membrane trafficking in the pathway. We will also discuss how different plant viruses may interact with the host secretory pathway for their efficient replication and spread, with a focus on tobacco mosaic virus and turnip mosaic virus. PMID:23335933

  13. Biomass utilization

    SciTech Connect

    Coute, W.A. (ed.)

    1983-01-01

    Forty papers are presented in 6 sections: Biomass utilization - the concept; The raw material and its preparation; The structure and chemical composition of biomass; Conversion methods - biological; Conversion methods - thermochemical; and Engineering and economics in biomass utilization. Ten papers are of particular forestry interest: Forest inventories as the basis for a continuous monitoring of forest biomass resources (Cunia, T.); Aerial photo biomass equation (Kasile, J.); Forest biomass utilization in Greece (Tsoumis, C.); Mass propagation of selected trees for biomass by tissue culture (Venketeswaran, S. et al.); The anatomy, ultrastructure and chemical composition of wood (Coete, W.A.); Some structural characteristics of acid hydrolysis lignins (Papadopoulos, J.); Thermochemical routes to chemicals, fuels and energy from forestry and agricultural residues (Soltes, E.J.); Pyrolysis of wood wastes (Figueiredo, J.L. et al.); Efficient utilization of woody biomass: a cellulose-particleboard-synfuels model (Young, R.A.; Achmadi, S.); and Methanol from wood, a state of the art review (Beenackers, A.A.C.M.; Swaaij, W.P.M. van).

  14. Phosphate Utilization Efficiency Correlates with Expression of Low-Affinity Phosphate Transporters and Noncoding RNA, IPS1, in Barley1[W

    PubMed Central

    Huang, Chun Y.; Shirley, Neil; Genc, Yusuf; Shi, Bujun; Langridge, Peter

    2011-01-01

    Genetic variation in phosphorus (P) efficiency exists among wheat (Triticum aestivum) and barley (Hordeum vulgare) genotypes, but the underlying mechanisms for the variation remain elusive. High- and low-affinity phosphate (Pi) PHT1 transporters play an indispensable role in P acquisition and remobilization. However, little is known about genetic variation in PHT1 gene expression and association with P acquisition efficiency (PAE) and P utilization efficiency (PUE). Here, we present quantitative analyses of transcript levels of high- and low-affinity PHT1 Pi transporters in four barley genotypes differing in PAE. The results showed that there was no clear pattern in the expression of four paralogs of the high-affinity Pi transporter HvPHT1;1 among the four barley genotypes, but the expression of a low-affinity Pi transporter, HvPHT1;6, and its close homolog HvHPT1;3 was correlated with the genotypes differing in PUE. Interestingly, the expression of HvPHT1;6 and HvPHT1;3 was correlated with the expression of HvIPS1 (for P starvation inducible; noncoding RNA) but not with HvIPS2, suggesting that HvIPS1 plays a distinct role in the regulation of the low-affinity Pi transporters. In addition, high PUE was found to be associated with high root-shoot ratios in low-P conditions, indicating that high carbohydrate partitioning into roots occurs simultaneously with high PUE. However, high PUE accompanying high carbon partitioning into roots could result in low PAE. Therefore, the optimization of PUE through the modification of low-affinity Pi transporter expression may assist further improvement of PAE for low-input agriculture systems. PMID:21606317

  15. Spectrum Trading with Insurance in Cognitive Radio Networks

    E-print Network

    Wang, Xinbing

    Spectrum Trading with Insurance in Cognitive Radio Networks Haiming Jin, Gaofei Sun, Xinbing Wang@cs.ust.hk Abstract--Market based spectrum trading has been extensively studied to realize efficient spectrum in spectrum trading so as to improve spectrum efficiency in CRNs. We show that by additionally purchasing

  16. Mining Spectrum Usage Data: a Large-scale Spectrum Measurement Study

    E-print Network

    Liu, Mingyan

    Mining Spectrum Usage Data: a Large-scale Spectrum Measurement Study Dawei Chen Dept. of Computer Dynamic spectrum access has been a subject of extensive study in recent years. The increasing volume of literature calls for a deeper understanding of the characteristics of cur- rent spectrum utilization

  17. Renewal-Theoretical Dynamic Spectrum Access in Cognitive Radio Networks with Unknown Primary Behavior

    E-print Network

    Jiang, Chunxiao; Liu, K J Ray; Ren, Yong

    2011-01-01

    Dynamic spectrum access in cognitive radio networks can greatly improve the spectrum utilization efficiency. Nevertheless, interference may be introduced to the Primary User (PU) when the Secondary Users (SUs) dynamically utilize the PU's licensed channels. If the SUs can be synchronous with the PU's time slots, the interference is mainly due to their imperfect spectrum sensing of the primary channel. However, if the SUs have no knowledge about the PU's exact communication mechanism, additional interference may occur. In this paper, we propose a dynamic spectrum access protocol for the SUs confronting with unknown primary behavior and study the interference caused by their dynamic access. Through analyzing the SUs' dynamic behavior in the primary channel which is modeled as an ON-OFF process, we prove that the SUs' communication behavior is a renewal process. Based on the Renewal Theory, we quantify the interference caused by the SUs and derive the corresponding close-form expressions. With the interference a...

  18. Roll-to-roll cohesive, coated, flexible, high-efficiency polymer light-emitting diodes utilizing ITO-free polymer anodes.

    PubMed

    Shin, Seongbeom; Yang, Minyang; Guo, L Jay; Youn, Hongseok

    2013-12-01

    This paper reports solution-processed, high-efficiency polymer light-emitting diodes fabricated by a new type of roll-to-roll coating method under ambient air conditions. A noble roll-to-roll cohesive coating system utilizes only natural gravity and the surface tension of the solution to flow out from the capillary to the surface of the substrate. Because this mechanism uses a minimally cohesive solution, the roll-to-roll cohesive coating can effectively realize an ultra-thin film thickness for the electron injection layer. In addition, the roll-to-roll cohesive coating enables the fabrication of a thicker polymer anode film more than 250 nm at one time by modification of the surface energy and without wasting the solution. It is observed that the standard sheet resistance deviation of the polymer anode is only 2.32 ?/? over 50 000 bending cycles. The standard sheet resistance deviation of the polymer anode in the different bending angles (0 to 180°) is 0.313 ?/?, but the case of the ITO-PET is 104.93 ?/?. The average surface roughness of the polymer anode measured by atomic force microscopy is only 1.06 nm. Because the surface of the polymer anode has a better quality, the leakage current of the polymer light-emitting diodes (PLEDs) using the polymer anode is much lower than that using the ITO-PET substrate. The luminous power efficiency of the two devices is 4.13 lm/W for the polymer anode and 3.21 lm/W for the ITO-PET. Consequently, the PLEDs made by using the polymer anode exhibited 28% enhanced performance because the polymer anode represents not only a higher transparency than the ITO-PET in the wavelength of 560 nm but also greatly reduced roughness. The optimized the maximum current efficiency and power efficiency of the device show around 6.1 cd/A and 5.1 lm/W, respectively, which is comparable to the case of using the ITO-glass. PMID:23784859

  19. Threshold Based Call Admission Control for QoS Provisioning in Cellular Wireless Networks with Spectrum Renting

    Microsoft Academic Search

    Show-Shiow Tzeng; Ching-Wen Huang

    2008-01-01

    \\u000a Radio spectrum is scarce and precious resource in wireless networks. To efficiently utilize radio spectrum, idle radio channels\\u000a can be rented between various wireless networks and a wireless network renting out its idle channels can withdraw its radio\\u000a channels when requiring its channels. However, the rental and withdrawal of radio channels result in two phenomena. One is\\u000a the variation in

  20. Efficient Utilization of SIMD Extensions

    Microsoft Academic Search

    Franz Franchetti; Stefan Kral; Juergen Lorenz; Christoph W. Ueberhuber

    2005-01-01

    This paper targets automatic performance tuning of numerical kernels in the presence of multilayered memory hierarchies and single-instruction, multiple-data (SIMD) parallelism. The studied SIMD instruction set extensions include Intel's SSE family, AMD's 3DNow!, Motorola's AltiVec, and IBM's BlueGene\\/L SIMD instructions. FFTW, ATLAS, and SPIRAL demonstrate that near-optimal performance of numerical kernels across a variety of modern computers featuring deep memory

  1. Iterative interference cancellation for high spectral efficiency satellite communications

    Microsoft Academic Search

    Bassel F. Beidas; Hesham El Gamal; Stan Kay

    2002-01-01

    The problem of efficient utilization of the frequency spectrum for satellite systems is investigated; one which results as a consequence of highly crowding adjacent channels. An analytical characterization of the resulting interference channel is introduced and then exploited for interference cancellation. Two classes of cancelers are investigated. The first approach does not benefit from the forward error control (FEC) coding

  2. Multiplex ligation-dependent probe amplification for genetic screening in autism spectrum disorders: Efficient identification of known microduplications and identification of a novel microduplication in ASMT

    PubMed Central

    Cai, Guiqing; Edelmann, Lisa; Goldsmith, Juliet E; Cohen, Ninette; Nakamine, Alisa; Reichert, Jennifer G; Hoffman, Ellen J; Zurawiecki, Danielle M; Silverman, Jeremy M; Hollander, Eric; Soorya, Latha; Anagnostou, Evdokia; Betancur, Catalina; Buxbaum, Joseph D

    2008-01-01

    Background It has previously been shown that specific microdeletions and microduplications, many of which also associated with cognitive impairment (CI), can present with autism spectrum disorders (ASDs). Multiplex ligation-dependent probe amplification (MLPA) represents an efficient method to screen for such recurrent microdeletions and microduplications. Methods In the current study, a total of 279 unrelated subjects ascertained for ASDs were screened for genomic disorders associated with CI using MLPA. Fluorescence in situ hybridization (FISH), quantitative polymerase chain reaction (Q-PCR) and/or direct DNA sequencing were used to validate potential microdeletions and microduplications. Methylation-sensitive MLPA was used to characterize individuals with duplications in the Prader-Willi/Angelman (PWA) region. Results MLPA showed two subjects with typical ASD-associated interstitial duplications of the 15q11-q13 PWA region of maternal origin. Two additional subjects showed smaller, de novo duplications of the PWA region that had not been previously characterized. Genes in these two novel duplications include GABRB3 and ATP10A in one case, and MKRN3, MAGEL2 and NDN in the other. In addition, two subjects showed duplications of the 22q11/DiGeorge syndrome region. One individual was found to carry a 12 kb deletion in one copy of the ASPA gene on 17p13, which when mutated in both alleles leads to Canavan disease. Two subjects showed partial duplication of the TM4SF2 gene on Xp11.4, previously implicated in X-linked non-specific mental retardation, but in our subsequent analyses such variants were also found in controls. A partial duplication in the ASMT gene, located in the pseudoautosomal region 1 (PAR1) of the sex chromosomes and previously suggested to be involved in ASD susceptibility, was observed in 6–7% of the cases but in only 2% of controls (P = 0.003). Conclusion MLPA proves to be an efficient method to screen for chromosomal abnormalities. We identified duplications in 15q11-q13 and in 22q11, including new de novo small duplications, as likely contributing to ASD in the current sample by increasing liability and/or exacerbating symptoms. Our data indicate that duplications in TM4SF2 are not associated with the phenotype given their presence in controls. The results in PAR1/PAR2 are the first large-scale studies of gene dosage in these regions, and the findings at the ASMT locus indicate that further studies of the duplication of the ASMT gene are needed in order to gain insight into its potential involvement in ASD. Our studies also identify some limitations of MLPA, where single base changes in probe binding sequences alter results. In summary, our studies indicate that MLPA, with a focus on accepted medical genetic conditions, may be an inexpensive method for detection of microdeletions and microduplications in ASD patients for purposes of genetic counselling if MLPA-identified deletions are validated by additional methods. PMID:18925931

  3. The Storage Spectrum

    NSDL National Science Digital Library

    Virtually every modern computer system incorporates several different storage technologies to process data efficiently. A gentle introduction to data storage is given on this site, part of Red Hat, Inc.'s Linux System Administration Primer. The topics covered include: "The Storage Spectrum," "CPU Registers," "Cache Memory," "Cache Levels," "Main Memory - RAM," "Hard Drives," and "Off-Line Backup Storage."

  4. Spectrum Recombination.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1984-01-01

    Describes several methods of executing lecture demonstrations involving the recombination of the spectrum. Groups the techniques into two general classes: bringing selected portions of the spectrum together using lenses or mirrors and blurring the colors by rapid movement or foreshortening. (JM)

  5. Wideband Spectrum Sensing in Cognitive Radio Networks

    Microsoft Academic Search

    Zhi Quan; Shuguang Cui; Ali H. Sayed; H. Vincent Poor

    2008-01-01

    Spectrum sensing is an essential enabling function- ality for cognitive radio networks to detect spectrum holes and opportunistically use the under-utilized frequency bands without causing harmful interference to legacy networks. This paper introduces a novel wideband spectrum sensing technique, called multiband joint detection, which jointly detects the signal energy levels over multiple frequency bands rather than consider one band at

  6. Measurements of the modulation transfer function, normalized noise power spectrum and detective quantum efficiency for two flat panel detectors: a fluoroscopic and a cone beam computer tomography flat panel detectors.

    PubMed

    Benítez, Ricardo Betancourt; Ning, Ruola; Conover, David; Liu, Shaohua

    2009-01-01

    The physical performance of two Flat Panel Detectors has been evaluated. The first Flat Panel Detector is for Fluoroscopic applications, Varian PaxScan 2520, and the second is for Cone Beam Computer Tomography applications, Varian PaxScan 4030CB. First, the spectrum of the X-ray source was measured. Second, the linearity of the detectors was investigated by using an ionization chamber and the average ADU values of the detectors. Third, the temporal resolution was characterized by evaluating their image lag. Fourth, their spatial resolution was characterized by the pre-sampling Modulation Transfer Function. Fifth, the Normalized Noise Power Spectrum was calculated for various exposures levels. Finally, the Detective Quantum Efficiency was obtained as a function of spatial frequency and entrance exposure. The results illustrate that the physical performance in Detective Quantum Efficiency and Normalized Noise Power Spectrum of the Cone Beam Computer Tomography detector is superior to that of the fluoroscopic detector whereas the latter detector has a higher spatial resolution as demonstrated by larger values of its Modulation Transfer Function at large spatial frequencies. PMID:19923685

  7. ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS CROSS-CUTTING R&D ON ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS FOR MORE EFFICIENT AND AFFORDABLE USE OF SOLAR ENERGY IN BUILDINGS AND HYBRID PHOTOBIOREACTORS

    SciTech Connect

    Byard D. Wood; Jeff D. Muhs

    2002-09-01

    This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports day light from a paraboloidal dish concentrator to a luminaire via a large core polymer fiber optic. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of day lighting and fluorescent lighting for office lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. The secondary mirror consists of eight planar-segmented mirrors that direct the visible part of the spectrum to eight fibers (receiver) and subsequently to eight luminaires. This results in about 8,200 lumens incident at each fiber tip. Each fiber can illuminate about 16.7 m{sup 2} (180 ft{sup 2}) of office space. The IR spectrum is directed to a thermophotovoltaic array to produce electricity. This report describes eleven investigations on various aspects of the system. Taken as a whole, they confirm the technical feasibility of this technology.

  8. ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS CROSS-CUTTING R&D ON ADAPTIVE FULL SPECTRUM SOLAR ENERGY SYSTEMS FOR MORE EFFICIENT AND AFFORDABLE USE OF SOLAR ENERGY IN BUILDINGS AND HYBRID PHOTOBIOREACTORS

    SciTech Connect

    Byard D. Wood; Jeff D. Muhs

    2003-10-01

    This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports day light from a paraboloidal dish concentrator to a luminaire via a large core polymer fiber optic. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of day lighting and fluorescent lighting for office lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. The secondary mirror consists of eight planar-segmented mirrors that direct the visible part of the spectrum to eight fibers (receiver) and subsequently to eight luminaires. This results in about 8,200 lumens incident at each fiber tip. Each fiber can illuminate about 16.7 m{sup 2} (180 ft{sup 2}) of office space. The IR spectrum is directed to a thermophotovoltaic array to produce electricity. This report emphasizes the design of the thermophotovoltaic receiver and the whole system simulation model.

  9. E240V Substitution Increases Catalytic Efficiency toward Ceftazidime in a New Natural TEMType Extended-Spectrum  Lactamase, TEM149, from Enterobacter aerogenes and Serratia marcescens Clinical Isolates

    Microsoft Academic Search

    Mariagrazia Perilli; Giuseppe Celenza; Francesca De Santis; Cristina Pellegrini; Chiara Forcella; Gian Maria Rossolini; Stefania Stefani; Gianfranco Amicosante

    2008-01-01

    The aim of this study was to characterize a novel extended-spectrum -lactamase that belongs to the TEM family, the TEM-149 enzyme, and that was isolated from the urine of two hospitalized patients from different hospitals in southern Italy. The peculiarity of this enzyme was the finding of a valine residue at position 240. The array of amino acid substitutions found

  10. Decline in Topsoil Microbial Quotient, Fungal Abundance and C Utilization Efficiency of Rice Paddies under Heavy Metal Pollution across South China

    PubMed Central

    Liu, Yongzhuo; Zhou, Tong; Crowley, David; Li, Lianqing; Liu, Dawen; Zheng, Jinwei; Yu, Xinyan; Pan, Genxing; Hussain, Qaiser; Zhang, Xuhui; Zheng, Jufeng

    2012-01-01

    Agricultural soils have been increasingly subject to heavy metal pollution worldwide. However, the impacts on soil microbial community structure and activity of field soils have been not yet well characterized. Topsoil samples were collected from heavy metal polluted (PS) and their background (BGS) fields of rice paddies in four sites across South China in 2009. Changes with metal pollution relative to the BGS in the size and community structure of soil microorganisms were examined with multiple microbiological assays of biomass carbon (MBC) and nitrogen (MBN) measurement, plate counting of culturable colonies and phospholipids fatty acids (PLFAs) analysis along with denaturing gradient gel electrophoresis (DGGE) profile of 16S rRNA and 18S rRNA gene and real-time PCR assay. In addition, a 7-day lab incubation under constantly 25°C was conducted to further track the changes in metabolic activity. While the decrease under metal pollution in MBC and MBN, as well as in culturable population size, total PLFA contents and DGGE band numbers of bacteria were not significantly and consistently seen, a significant reduction was indeed observed under metal pollution in microbial quotient, in culturable fungal population size and in ratio of fungal to bacterial PLFAs consistently across the sites by an extent ranging from 6% to 74%. Moreover, a consistently significant increase in metabolic quotient was observed by up to 68% under pollution across the sites. These observations supported a shift of microbial community with decline in its abundance, decrease in fungal proportion and thus in C utilization efficiency under pollution in the soils. In addition, ratios of microbial quotient, of fungal to bacterial and qCO2 are proved better indicative of heavy metal impacts on microbial community structure and activity. The potential effects of these changes on C cycling and CO2 production in the polluted rice paddies deserve further field studies. PMID:22701725

  11. ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS Cross-Cutting R & D on adaptive full-spectrum solar energy systems for more efficient and affordable use of solar energy in buildings and hybrid photobioreactors

    SciTech Connect

    Byard D. Wood; David L. Beshears

    2006-02-01

    This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports daylight from a paraboloidal dish concentrator to a luminaire via a bundle of polymer fiber optics. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of daylighting and electric lighting for space/task lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. For the third generation (beta) system, the secondary mirror is an ellipsoidal mirror that directs the visible light into a bundle of 3 mm diameter fibers. The IR spectrum is filtered out to minimize unnecessary heating at the fiber entrance region. This report describes the following investigations: Niche applications for HSL technology, Luminaire design characteristics for linear and point lighting fixtures, and Daylight affects on productivity.

  12. DOTA: A Double Truthful Auction for Spectrum Allocation in Dynamic Spectrum Access

    E-print Network

    Zhou, Yuanyuan

    DOTA: A Double Truthful Auction for Spectrum Allocation in Dynamic Spectrum Access Qinhui Wang Science and Engineering, University of Aizu, Japan Abstract--Spectrum auctions have been proposed as an effec- tive approach to fairly and efficiently trade the scarce spectrum resource among wireless users

  13. Electromagnetic Spectrum

    NSDL National Science Digital Library

    Part of the larger Imagine the Universe educational site, the Electromagnetic Spectrum site is another great resource from NASA. The site gives clear and easy-to-understand explanations, while providing keywords throughout the page that are linked to a dictionary of terms for easy access to further information. Students will enjoy the colorful illustrations accompanying the text, which vertically follow the spectrum from radio to gamma rays, while teachers will appreciate the related lesson plans link that will help reinforce the learning.

  14. Smart Radio Spectrum Management for Cognitive Radio

    E-print Network

    Bhattacharya, Partha Pratim; Gera, Rishita; Agarwal, Anjali

    2011-01-01

    Today's wireless networks are characterized by fixed spectrum assignment policy. The limited available spectrum and the inefficiency in the spectrum usage necessitate a new communication paradigm to exploit the existing wireless spectrum opportunistically. Cognitive radio is a paradigm for wireless communication in which either a network or a wireless node changes its transmission or reception parameters to communicate efficiently avoiding interference with licensed or unlicensed users. In this work, a fuzzy logic based system for spectrum management is proposed where the radio can share unused spectrum depending on some parameters like distance, signal strength, node velocity and availability of unused spectrum. The system is simulated and is found to give satisfactory results.

  15. A preliminary report on the photoionization efficiency spectrum, ionization energy and heat of formation of Br{sub 2}O; and the appearance energy of BrO{sup +} (Br{sub 2}O)

    SciTech Connect

    Thorn, R.P. Jr.; Monks, P.S.; Stief, L.J.; Kuo, S.C.; Zhang, Z.; Klemm, R.B.

    1995-08-01

    We report experimental results for the photoionization efficiency (PIE) spectrum of Br{sub 2}O along with the ionization energy (derived form the ionization threshold) and the appearance energy (AE) of BrO{sup +} (Br{sub 2}O). A value for the heat of formation of Br{sub 2}O is derived form the AE result. Experiments were performed by employing a discharge flow-photoionization mass spectrometer (DF-PIMS) apparatus coupled to beamline U-11 at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory.

  16. Dynamic Contract Trading and Portfolio Optimization in Spectrum Markets

    Microsoft Academic Search

    G. Kasbekar; P. Muthusamy; S. Sarkar; K. Kar; A. Gupta

    We address the question of optimal trading of bandwidth (service) contracts in wireless spectrum markets, for the primary as well as the secondary spectrum providers in this context. We propose a structured spectrum market and consider two basic types of spectrum contracts that can help attain desired flexibilities and trade-offs in terms of service quality, spectrum usage efficiency and pricing

  17. Optimization of Spectrum Sensing for Opportunistic Spectrum Access in Cognitive Radio Networks

    Microsoft Academic Search

    Amir Ghasemi; Elvino S. Sousa

    2007-01-01

    Motivated by the low utilization of the licensed spectrum across many frequency bands, sensing-based oppor- tunistic spectrum access has recently emerged as an alternative to the outdated exclusive spectrum access policy. Under this new paradigm, a secondary (unlicensed) user monitors a primary (licensed) frequency band for a given time and opportunistically transmits if it does not detect any ongoing licensed

  18. Kinetics of blood lipoprotein spectrum indices in patients with angina pectoris during and after low-intensity laser therapy as a paraclinical criterion for treatment efficiency

    NASA Astrophysics Data System (ADS)

    Babushkina, G. V.; Kartelishev, A. V.

    2001-04-01

    An investigation was made of applying (lambda) equals 0.63 micrometers laser radiation in treating 403 patients affected by angina pectoris. The patients were administered a course of combined laser therapy consisting of the intravenous laser irradiation of blood combined with laser acupuncture. Apart from that, the patients took the maintenance doses of antianginal preparations and therapeutic doses of vitamins A and E. The blood lipoprotein spectrum revealed that this combined laser therapy was capable of producing an antiatherogenic effect. It was also found that the most effective exposure time of laser radiation was in the range of 10 to 15 min.

  19. Production of protein by fungi from agricultural wastes. II. Effect of carbon/nitrogen ratio on the efficiency of substrate utilization and protein production by Rhizoctonia melongina, Pleurotus ostreatus, and Coprinus aratus.

    PubMed

    Jauhri, K S; Sen, A

    1978-01-01

    An attempt was made to standardize the C/N ratio at which maximum protein production may be achieved by Rhizoctonia melongina, Pleurotus ostreatus, and Coprinus aratus, using sugarcane bagasse for the former two and wheat straw for the latter in the liquid medium. Three different ways of changing the C/N ratios were tried. The optimum levels of carbon and nitrogen required for the best yield, substrate utilization, and protein production efficiency were worked out. PMID:571180

  20. A Framework for Radio Frequency Spectrum Measurement and Analysis

    E-print Network

    Kansas, University of

    A Framework for Radio Frequency Spectrum Measurement and Analysis V. Rory Petty ITTC-FY2008-TR frequency spectrum is utilized. The radio frequency spectrum is an important national resource that impacts allocation and the burgeoning problem of spectrum scarcity have prompted an examination of how the radio

  1. Building a spectrum map for future cognitive radio technology

    Microsoft Academic Search

    Yun Li; Trung Tran Quang; Yoshihiro Kawahara; Tohru Asami; Masanori Kusunoki

    2009-01-01

    Monitoring the spectrum utilization and capturing the available spectrum bands is the groundwork for the Cognitive Radio (CR) technologies. Because the spectrum management has been a politically as well as a technically sensitive issue, it is usually very hard to access the open data of real spectrum usage. In this sense, we believe grass-roots data collections are important. For these

  2. Effectiveness and Efficiency of Peer and Adult Models Used in Video Modeling in Teaching Pretend Play Skills to Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Sani-Bozkurt, Sunagul; Ozen, Arzu

    2015-01-01

    This study aimed to examine whether or not there was any difference in the effectiveness and efficiency of the presentation of video modeling interventions using peer and adult models in teaching pretend play skills to children with ASD and to examine the views of parents about the study. Participants were two boys and one girl, aged 5-6 years…

  3. Full spectrum absorption through 1eV-tuning in a p-i (MQW)-n high efficiency solar cell

    Microsoft Academic Search

    A. C. Varonides; R. A. Spalletta

    2009-01-01

    Demonstration of a highly successful new solar cell design is pursued in this letter. We propose a new high efficiency solar cell design, consisting of two cells in tandem: the top cell is a triple n+ - n - p hetero-junction and the bottom one is a p - i - n multi-quantum well cell tuned at 1 eV through

  4. Joint transform time-integrating acousto-optic correlator for chirp spectrum analysis

    Microsoft Academic Search

    P. S. Guilfoyle; D. L. Hecht; D. L. Steinmetz

    1980-01-01

    A time-integrating optical processor is configured for one-dimensional chirp correlation spectrum analysis. A unique optical implementation, utilizing TeO2 shear wave acousto-optic cells, is designed to operate in a configuration which allows wide bandwidth diffraction to both the positive and negative first diffraction orders. The result is high optical throughput efficiency, excellent fringe visibility, and a coaxial system design. Chirp linearity

  5. Spectrum formation in supernovae - Numerical techniques

    NASA Technical Reports Server (NTRS)

    Eastman, Ronald G.; Pinto, Philip A.

    1993-01-01

    The study combines several novel techniques for spectrum simulation in the Eddington computer program which solves the comoving frame equation of transfer coupled with the statistical and radiative equilibrium equations. One of these is a generalization of the accelerated lambda iteration (ALI) scheme to include an approximate frequency-derivative operator. This greatly enhances the convergence rate of ALI in optically thick, high-velocity shear flows. Another is a partial linearization technique which is capable of efficiently solving a very large number of rate equations on a moderately sized computer. An expansion opacity and emissivity approximation is derived which makes it possible to determine the effect on the transfer and statistical equilibrium of a very large number of lines not explicitly represented in the frequency grid and additionally to treat line-blanketing from species not explicitly included in the rate equations. The utility of these techniques is illustrated with models of two supernovae.

  6. EFFECT OF YEAST CULTURE ON EFFICIENCY OF NUTRIENT UTILIZATION FOR MILK PRODUCTION AND IMPACT ON FIBER DIGESTIBILITY AND FECAL PARTICLE SIZE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objectives of this study were to evaluate the effect of Diamond V XP Yeast Culture on milk production, fiber digestibility and fecal particle size. Two groups of 111 cows each (average DIM of 179 and 191 at initiation of trial) were utilized in a two-period (40 d and 49 d) switchback design. Cows ...

  7. GUIDELINES FOR NOX CONTROL BY COMBUSTION MODIFICATION FOR COAL-FIRED UTILITY BOILERS. PROCEDURES FOR REDUCTION OF NOX EMISSIONS AND MAXIMIZATION OF BOILER EFFICIENCY

    EPA Science Inventory

    The report, which has been reviewed by industry experts, reflects the experience developed in successfully applying combustion modifications to reduce NOx emissions from coal-fired utility boilers. Although the report emphasizes coal-fired equipment, the same principles can be ap...

  8. Final Report for DE-FG36-08GO18007 "All-Inorganic, Efficient Photovoltaic Solid State Devices Utilizing Semiconducting Colloidal Nanocrystal Quantum Dots"

    SciTech Connect

    Vladimir Bulovic and Moungi Bawendi

    2011-09-30

    We demonstrated robust colloidal quantum dot (QD) photovoltaics with high internal quantum efficiencies. In our structures, device durability is derived from use of all-inorganic atmospherically-stable semiconducting metal-oxide films together with QD photoreceptors. We have shown that both QD and metal-oxide semiconducting films and contacts are amenable to room temperature processing under minimal vacuum conditions, enabling large area processing of PV structures of high internal efficiency. We generated the state of the art devices with power conversion efficiency of more than 4%, and have shown that efficiencies as high as 9% are achievable in the near-term, and as high as 17% in the long-term.

  9. Primordial Power Spectrum Reconstruction

    E-print Network

    Pia Mukherjee; Yun Wang

    2006-01-11

    In order to reconstruct the initial conditions of the universe it is important to devise a method that can efficiently constrain the shape of the power spectrum of primordial matter density fluctuations in a model-independent way from data. In an earlier paper we proposed a method based on the wavelet expansion of the primordial power spectrum. The advantage of this method is that the orthogonality and multiresolution properties of wavelet basis functions enable information regarding the shape of $P_{\\rm in}(k)$ to be encoded in a small number of non-zero coefficients. Any deviation from scale-invariance can then be easily picked out. Here we apply this method to simulated data to demonstrate that it can accurately reconstruct an input $P_{\\rm in}(k)$, and present a prescription for how this method should be used on future data.

  10. Dynamic Pricing Approach for Spectrum Allocation in Wireless Networks with Selfish Users

    Microsoft Academic Search

    Zhu Ji; K. J. Ray Liu

    2006-01-01

    Dynamic spectrum allocation becomes a promising approach to increase the spectrum efficiency for wireless net- works. In this paper, we consider the spectrum allocation in wireless networks with multiple selfish legacy spectrum holders and unlicensed users as multi-stage dynamic games. A dynamic pricing approach is proposed to optimize overall spectrum efficiency while keeping the participating incentives of the users based

  11. Visible Spectrum Incandescent Selective Emitter

    SciTech Connect

    Sonsight Inc.

    2004-04-30

    The purpose of the work performed was to demonstrate the feasibility of a novel bi-layer selective emitter. Selective emitters are incandescent radiant bodies with emissivities that are substantially larger in a selected part of the radiation spectrum, thereby significantly shifting their radiated spectral distribution from that of a blackbody radiating at the same temperature. The major research objectives involved answering the following questions: (1) What maximum VIS/NIR radiant power and emissivity ratios can be attained at 2650 K? (2) What is the observed emitter body life and how does its performance vary with time? (3) What are the design tradeoffs for a dual heating approach in which both an internally mounted heating coil and electrical resistance self-heating are used? (4) What are the quantitative improvements to be had from utilizing a bi-layer emitter body with a low emissivity inner layer and a partially transmissive outer layer? Two approaches to obtaining selective emissivity were investigated. The first was to utilize large optical scattering within an emitter material with a spectral optical absorption that is much greater within the visible spectrum than that within the NIR. With this approach, an optically thick emitter can radiate almost as if optically thin because essentially, scattering limits the distance below the surface from which significant amounts of internally generated radiation can emerge. The performance of thin emitters was also investigated (for optically thin emitters, spectral emissivity is proportional to spectral absorptivity). These emitters were fabricated from thin mono-layer emitter rods as well as from bi-layer rods with a thin emitter layer mounted on a substrate core. With an initially estimated energy efficiency of almost three times that of standard incandescent bulbs, a number of energy, economic and environmental benefits such as less energy use and cost, reduced CO{sub 2} emissions, and no mercury contamination was initially projected. The work performed provided answers to a number of important questions. The first is that, with the investigated approaches, the maximum sustained emitter efficiencies are about 1.5 times that of a standard incandescent bulb. This was seen to be the case for both thick and thin emitters, and for both mono-layer and bi-layer designs. While observed VIS/NIR ratios represent improvements over standard incandescent bulbs, it does not appear sufficient to overcome higher cost (i.e. up to five times that of the standard bulb) and ensure commercial success. Another result is that high temperatures (i.e. 2650 K) are routinely attainable without platinum electrodes. This is significant for reducing material costs. A novel dual heating arrangement and insulated electrodes were used to attain these temperatures. Another observed characteristic of the emitter was significant grain growth soon after attaining operating temperatures. This is an undesirable characteristic that results in substantially less optical scattering and spectral selectivity, and which significantly limits emitter efficiencies to the values reported. Further work is required to address this problem.

  12. A Wavelet Approach to Wideband Spectrum Sensing for Cognitive Radios

    Microsoft Academic Search

    Zhi Tian; Georgios B. Giannakis

    2006-01-01

    In cognitive radio networks, the first cognitive task preceding any form of dynamic spectrum management is the sensing and identification of spectrum holes in wireless environments. This paper develops a wavelet approach to efficient spectrum sensing of wideband channels. The signal spectrum over a wide frequency band is decomposed into elementary building blocks of subbands that are well characterized by

  13. Efficient Dynamic Spectrum Sharing Through Rate Compensation and Spectrum Handoff

    E-print Network

    Paris-Sud XI, Université de

    Lertsinsrubtavee, Naceur Malouch and Serge Fdida Laboratoire d'Informatiqe de Paris 6 (LIP6) Universit´e Pierre et Marie Curie (UPMC) Paris, France Email: {Adisorn.Lertsinsrubtavee, Naceur.Malouch, Serge.Fdida}@lip6.fr

  14. Study on utilization of cold energy from natural ice—Ice-making efficiency of small ice containers stacked in a cold room

    Microsoft Academic Search

    Masato Kimura; Shin-ichi Urano; Keiji Okada; Torahiko Saeki

    2010-01-01

    Recently, the efficient use of cold energy, a type of natural energy derived from snow and ice, has been studied as an energy-saving measure to cut emissions of carbon dioxide. For example, the Ice Shelter, which is constructed with natural ice, was developed to create an environment with low ambient temperature and high humidity using latent heat absorbed or released

  15. YEAR 2 BIOMASS UTILIZATION

    SciTech Connect

    Christopher J. Zygarlicke

    2004-11-01

    This Energy & Environmental Research Center (EERC) Year 2 Biomass Utilization Final Technical Report summarizes multiple projects in biopower or bioenergy, transportation biofuels, and bioproducts. A prototype of a novel advanced power system, termed the high-temperature air furnace (HITAF), was tested for performance while converting biomass and coal blends to energy. Three biomass fuels--wood residue or hog fuel, corn stover, and switchgrass--and Wyoming subbituminous coal were acquired for combustion tests in the 3-million-Btu/hr system. Blend levels were 20% biomass--80% coal on a heat basis. Hog fuel was prepared for the upcoming combustion test by air-drying and processing through a hammer mill and screen. A K-Tron biomass feeder capable of operating in both gravimetric and volumetric modes was selected as the HITAF feed system. Two oxide dispersion-strengthened (ODS) alloys that would be used in the HITAF high-temperature heat exchanger were tested for slag corrosion rates. An alumina layer formed on one particular alloy, which was more corrosion-resistant than a chromia layer that formed on the other alloy. Research activities were completed in the development of an atmospheric pressure, fluidized-bed pyrolysis-type system called the controlled spontaneous reactor (CSR), which is used to process and condition biomass. Tree trimmings were physically and chemically altered by the CSR process, resulting in a fuel that was very suitable for feeding into a coal combustion or gasification system with little or no feed system modifications required. Experimental procedures were successful for producing hydrogen from biomass using the bacteria Thermotoga, a deep-ocean thermal vent organism. Analytical procedures for hydrogen were evaluated, a gas chromatography (GC) method was derived for measuring hydrogen yields, and adaptation culturing and protocols for mutagenesis were initiated to better develop strains that can use biomass cellulose. Fly ash derived from cofiring coal with waste paper, sunflower hulls, and wood waste showed a broad spectrum of chemical and physical characteristics, according to American Society for Testing and Materials (ASTM) C618 procedures. Higher-than-normal levels of magnesium, sodium, and potassium oxide were observed for the biomass-coal fly ash, which may impact utilization in cement replacement in concrete under ASTM requirements. Other niche markets for biomass-derived fly ash were explored. Research was conducted to develop/optimize a catalytic partial oxidation-based concept for a simple, low-cost fuel processor (reformer). Work progressed to evaluate the effects of temperature and denaturant on ethanol catalytic partial oxidation. A catalyst was isolated that had a yield of 24 mole percent, with catalyst coking limited to less than 15% over a period of 2 hours. In biodiesel research, conversion of vegetable oils to biodiesel using an alternative alkaline catalyst was demonstrated without the need for subsequent water washing. In work related to biorefinery technologies, a continuous-flow reactor was used to react ethanol with lactic acid prepared from an ammonium lactate concentrate produced in fermentations conducted at the EERC. Good yields of ester were obtained even though the concentration of lactic acid in the feed was low with respect to the amount of water present. Esterification gave lower yields of ester, owing to the lowered lactic acid content of the feed. All lactic acid fermentation from amylose hydrolysate test trials was completed. Management activities included a decision to extend several projects to December 31, 2003, because of delays in receiving biomass feedstocks for testing and acquisition of commercial matching funds. In strategic studies, methods for producing acetate esters for high-value fibers, fuel additives, solvents, and chemical intermediates were discussed with several commercial entities. Commercial industries have an interest in efficient biomass gasification designs but are waiting for economic incentives. Utility, biorefinery, pulp and paper, or o

  16. Southern Energy Efficiency Center (SEEC)

    SciTech Connect

    Vieira, Robin; Sonne, Jeffrey; Withers, Charles; Cummings, James; Verdict, Malcolm; Roberts, Sydney

    2009-09-30

    The Southern Energy Efficiency Center (SEEC) builds collaborative partnerships with: state and local governments and their program support offices, the building delivery industry (designers, contractors, realtors and commissioning agents), product manufacturers and their supply chains, utilities and their program implementers, consumers and other stakeholders in order to forge a strong regional network of building energy efficiency allies. Through a project Steering Committee composed of the state energy offices and building industry stakeholders, the SEEC works to establish consensus-based goals, priorities and strategies at the regional, state and local levels that will materially advance the deployment of high-performance “beyond code” buildings. In its first Phase, SEEC will provide limited technical and policy support assistance, training, certification and education to a wide spectrum of the building construction, codes and standards, and the consumer marketplace.

  17. High efficiency 2 micrometer laser utilizing wing-pumped Tm{sup 3+} and a laser diode array end-pumping architecture

    DOEpatents

    Beach, R.J.

    1997-11-18

    Wing pumping a Tm{sup 3+} doped, end pumped solid state laser generates 2 {micro}m laser radiation at high average powers with high efficiency. Using laser diode arrays to end-pump the laser rod or slab in the wing of the Tm{sup 3+} absorption band near 785 nm results in 2-for-1 quantum efficiency in Tm{sup 3+} because high Tm{sup 3+} concentrations can be used. Wing pumping allows the thermal power generated in the rod or slab to be distributed over a large enough volume to make thermal management practical in the laser gain medium even at high average power operation. The approach is applicable to CW, Q-switched, and rep-pulsed free-laser operation. 7 figs.

  18. High efficiency 2 micrometer laser utilizing wing-pumped Tm.sup.3+ and a laser diode array end-pumping architecture

    DOEpatents

    Beach, Raymond J. (Livermore, CA)

    1997-01-01

    Wing pumping a Tm.sup.3+ doped, end pumped solid state laser generates 2 .mu.m laser radiation at high average powers with high efficiency. Using laser diode arrays to end-pump the laser rod or slab in the wing of the Tm.sup.3+ absorption band near 785 nm results in 2-for-1 quantum efficiency in Tm.sup.3+ because high Tm.sup.3+ concentrations can be used. Wing pumping allows the thermal power generated in the rod or slab to be distributed over a large enough volume to make thermal management practical in the laser gain medium even at high average power operation. The approach is applicable to CW, Q-switched, and rep-pulsed free-laser operation.

  19. NeXt generation\\/dynamic spectrum access\\/cognitive radio wireless networks: A survey

    Microsoft Academic Search

    Ian F. Akyildiz; Won-yeol Lee; Mehmet C. Vuran; Shantidev Mohanty

    2006-01-01

    Today's wireless networks are characterized by a fixed spectrum assignment policy. However, a large portion of the assigned spectrum is used sporadically and geographical variations in the utilization of assigned spectrum ranges from 15% to 85% with a high variance in time. The limited available spectrum and the inefficiency in the spectrum usage neces- sitate a new communication paradigm to

  20. Calculating Fired Heater Efficiency 

    E-print Network

    Harriz, J. T.; Ritter, E. L.

    1986-01-01

    Tracking utility and process heater efficiency leads to increased operator awareness and decreased fuel bills. A review of the Heat Loss and Input/Output methods of efficiency analyses is presented, along with a discussion of their relative accuracy...

  1. Hybrid spread spectrum radio system

    DOEpatents

    Smith, Stephen F. (London, TN); Dress, William B. (Camas, WA)

    2010-02-02

    Systems and methods are described for hybrid spread spectrum radio systems. A method includes modulating a signal by utilizing a subset of bits from a pseudo-random code generator to control an amplification circuit that provides a gain to the signal. Another method includes: modulating a signal by utilizing a subset of bits from a pseudo-random code generator to control a fast hopping frequency synthesizer; and fast frequency hopping the signal with the fast hopping frequency synthesizer, wherein multiple frequency hops occur within a single data-bit time.

  2. Application of ZnO nanoparticles to enhance photoluminescence in porous silicon and its possible utilization for improving the short wavelength quantum efficiency of silicon solar cell

    NASA Astrophysics Data System (ADS)

    Verma, Daisy; Kharkwal, Aneeta; Singh, S. N.; Singh, P. K.; Sharma, S. N.; Mehdi, S. S.; Husain, M.

    2014-11-01

    We have formed photoluminescent porous silicon (PS) layers and over which a ZnO layer (hereafter called ZnOPS layers) is deposited. We studied the photoluminescent properties of individual layers as well as the composite layer under excitation with 405 nm wavelength. Using the data of PL a theoretical analysis of a solar cell having such a composite layer of a given photoluminescent conversion efficiency ?PL on the front surface has been done. The condition of a photoluminescent composite layer (ZnOPS) useful for enhancing the spectral response of n+-p-p+ structured silicon solar cell has been identified.

  3. Market Structures for Wireless Services with Shared Spectrum

    E-print Network

    Kuzmanovic, Aleksandar

    Market Structures for Wireless Services with Shared Spectrum Randall Berry, Michael Honig--There has been much recent interest in allowing commercial providers to utilize federal spectrum on a shared investment. However, since the spectrum is shared, such a license would differ from traditional exclusive use

  4. Research on application of OFDM technology in cooperative spectrum sensing

    Microsoft Academic Search

    Shao Lulu; Song Qijun; Zhang Hongshun; Zhang Jiaping

    2009-01-01

    Cognitive radio (CR) is viewed as a novel approach for improving utilization of the precious radio spectrum. Spectrum sensing is one of the most important technologies in cognitive radio. A general presentation of OFDM technology and cooperative spectrum sensing are given in the first instance. In order to improve detection probability and reduce equipment complex and computation complex, to combine

  5. Genetic variation in feed consumption, growth, nutrient utilization efficiency and mitochondrial function within a farmed population of channel catfish (Ictalurus punctatus).

    PubMed

    Eya, Jonathan C; Ashame, Martha F; Pomeroy, Charles F; Manning, Bruce B; Peterson, Brian C

    2012-10-01

    We evaluated the effects of diets (32/4 or 36/6 percent protein/fat) and six channel catfish families for growth performance characteristics. Two families with fast- (C) and slow- (D) growth rate and with low and high feed efficiency (FE) were selected for analyses of mitochondrial complex enzymatic activities (I, II, III, and IV) and gene expression (ND1, CYTB, COX1, COX2, ATP6) levels in liver, muscle, and intestine. There were significant differences in growth rate and nutrient retention among the families. Mitochondrial enzymatic complex activities (I-V) in the tissues were all lower in family C. Four of the five genes were down-regulated in the liver and up-regulated in the muscle for the fast growing family C. There were significant differences between diets for some mitochondrial respiratory chain enzyme activities and gene expression levels. Significant diet×family interactions were observed for some enzyme activities and gene expression levels. Changes in mitochondrial respiratory chain enzyme activities and gene expression levels provide insight into the cellular mechanisms of fish with differences in growth rate and feed efficiency. Results also suggest that genotype×diet interactions should be accounted for when considering strategies for using mitochondrial function as a criteria in channel catfish selection programs for improved growth performance characteristics. PMID:22691874

  6. A comprehensive review of reported heritable noggin-associated syndromes and proposed clinical utility of one broadly inclusive diagnostic term: NOG-related-symphalangism spectrum disorder (NOG-SSD).

    PubMed

    Potti, Tommy A; Petty, Elizabeth M; Lesperance, Marci M

    2011-08-01

    The NOG gene encodes noggin, a secreted polypeptide that is important for regulating multiple signaling pathways during human development, particularly in cartilage and bone. The hallmark of NOG-related syndromes is proximal symphalangism, defined by abnormal fusion of the proximal interphalangeal joints of the hands and feet. Many additional features secondary to NOG mutations are commonly but inconsistently observed, including a characteristic facies with a hemicylindrical nose, congenital conductive hearing loss due to stapes fixation, and hyperopia. The variable clinical presentations led to the designation of five different autosomal dominant syndromes, all subsequently found to have resulted from NOG mutations. These include (1) proximal symphalangism; (2) multiple synostoses syndrome 1; (3) stapes ankylosis with broad thumbs and toes; (4) tarsal-carpal coalition syndrome; and (5) brachydactyly type B2. Herein, we review the phenotypic features associated with mutations in the NOG gene, demonstrating the overlapping characteristics of these syndromes. Due to the variable phenotypic spectrum within families and among families with the same mutation, we propose a unifying term, NOG-related symphalangism spectrum disorder (NOG-SSD), to aid in the clinical recognition and evaluation of all affected individuals with these phenotypes. These NOG gene variants are available in a new locus-specific database (https://NOG.lovd.nl). PMID:21538686

  7. Low-cost, high-efficiency solar cells utilizing GaAs-on-Si technology. Annual subcontract report, 1 August 1991--31 July 1992

    SciTech Connect

    Vernon, S.M. [Spire Corp., Bedford, MA (United States)

    1993-04-01

    This report describes work to develop technology to deposit GaAs on Si using a nucleation layer of atomic-layer-epitaxy-grown GaAs or AlAs on Si. This ensures two-dimensional nucleation and should lead to fewer defects in the final GaAs layer. As an alternative, we also developed technology for depositing GaAs on sawtooth-patterned Si. Preliminary studies showed that this material can have a very low defect density, {approximately} 1 {times} 10{sup 5} cm{sup {minus}5}, as opposed to our conventionally grown GaAs on SL which has a typical defect density of over 1 {times}10{sup 7} cm{sup {minus}2}. Using these two now methods of GaAs-on-Si material growth, we made solar cells that are expected to show higher efficiencies than those of previous cells.

  8. Cardioprotection Resulting from Glucagon-Like Peptide-1 Administration Involves Shifting Metabolic Substrate Utilization to Increase Energy Efficiency in the Rat Heart

    PubMed Central

    Aravindhan, Karpagam; Bao, Weike; Harpel, Mark R.; Willette, Robert N.; Lepore, John J.; Jucker, Beat M.

    2015-01-01

    Previous studies have shown that glucagon-like peptide-1 (GLP-1) provides cardiovascular benefits independent of its role on peripheral glycemic control. However, the precise mechanism(s) by which GLP-1 treatment renders cardioprotection during myocardial ischemia remain unresolved. Here we examined the role for GLP-1 treatment on glucose and fatty acid metabolism in normal and ischemic rat hearts following a 30 min ischemia and 24 h reperfusion injury, and in isolated cardiomyocytes (CM). Relative carbohydrate and fat oxidation levels were measured in both normal and ischemic hearts using a 1-13C glucose clamp coupled with NMR-based isotopomer analysis, as well as in adult rat CMs by monitoring pH and O2 consumption in the presence of glucose or palmitate. In normal heart, GLP-1 increased glucose uptake (?64%, p<0.05) without affecting glycogen levels. In ischemic hearts, GLP-1 induced metabolic substrate switching by increasing the ratio of carbohydrate versus fat oxidation (?14%, p<0.01) in the LV area not at risk, without affecting cAMP levels. Interestingly, no substrate switching occurred in the LV area at risk, despite an increase in cAMP (?106%, p<0.05) and lactate (?121%, p<0.01) levels. Furthermore, in isolated CMs GLP-1 treatment increased glucose utilization (?14%, p<0.05) and decreased fatty acid oxidation (?15%, p<0.05) consistent with in vivo finding. Our results show that this benefit may derive from distinct and complementary roles of GLP-1 treatment on metabolism in myocardial sub-regions in response to this injury. In particular, a switch to anaerobic glycolysis in the ischemic area provides a compensatory substrate switch to overcome the energetic deficit in this region in the face of reduced tissue oxygenation, whereas a switch to more energetically favorable carbohydrate oxidation in more highly oxygenated remote regions supports maintaining cardiac contractility in a complementary manner. PMID:26098939

  9. Improvement of Carbon Dioxide Sweep Efficiency by Utilization of Microbial Permeability Profile Modification to Reduce the Amount of Oil Bypassed During Carbon Dioxide Flood

    SciTech Connect

    Darrel Schmitz; Lewis Brown F. Leo Lynch; Brenda Kirkland; Krystal Collins; William Funderburk

    2010-12-31

    The objective of this project was to couple microbial permeability profile modification (MPPM), with carbon dioxide flooding to improve oil recovery from the Upper Cretaceous Little Creek Oil Field situated in Lincoln and Pike counties, MS. This study determined that MPPM technology, which improves production by utilizing environmentally friendly nutrient solutions to simulate the growth of the indigenous microflora in the most permeable zones of the reservoir thus diverting production to less permeable, previously unswept zones, increased oil production without interfering with the carbon dioxide flooding operation. Laboratory tests determined that no microorganisms were produced in formation waters, but were present in cores. Perhaps the single most significant contribution of this study is the demonstration that microorganisms are active at a formation temperature of 115?C (239?F) by using a specially designed culturing device. Laboratory tests were employed to simulate the MPPM process by demonstrating that microorganisms could be activated with the resulting production of oil in coreflood tests performed in the presence of carbon dioxide at 66?C (the highest temperature that could be employed in the coreflood facility). Geological assessment determined significant heterogeneity in the Eutaw Formation, and documented relatively thin, variably-lithified, well-laminated sandstone interbedded with heavily-bioturbated, clay-rich sandstone and shale. Live core samples of the Upper Cretaceous Eutaw Formation from the Heidelberg Field, MS were quantitatively assessed using SEM, and showed that during MPPM permeability modification occurs ubiquitously within pore and throat spaces of 10-20 ?m diameter. Testing of the MPPM procedure in the Little Creek Field showed a significant increase in production occurred in two of the five production test wells; furthermore, the decline curve in each of the production wells became noticeably less steep. This project greatly extends the number of oil fields in which MPPM can be implemented.

  10. A Survey on Dynamic Spectrum Access Techniques for Cognitive Radio

    E-print Network

    Garhwal, Anita

    2012-01-01

    Cognitive radio (CR) is a new paradigm that utilizes the available spectrum band. The key characteristic of CR system is to sense the electromagnetic environment to adapt their operation and dynamically vary its radio operating parameters. The technique of dynamically accessing the unused spectrum band is known as Dynamic Spectrum Access (DSA). The dynamic spectrum access technology helps to minimize unused spectrum bands. In this paper, main functions of Cognitive Radio (CR) i.e. spectrum sensing, spectrum management, spectrum mobility and spectrum sharing are discussed. Then DSA models are discussed along with different methods of DSA such as Command and Control, Exclusive-Use, Shared Use of Primary Licensed User and Commons method. Game-theoretic approach using Bertrand game model, Markovian Queuing Model for spectrum allocation in centralized architecture and Fuzzy logic based method are also discussed and result are shown.

  11. Utilizing alkoxyphenyl substituents for side-chain engineering of efficient benzo[1,2-b:4,5-b']dithiophene-based small molecule organic solar cells.

    PubMed

    Du, Zhengkun; Chen, Weichao; Qiu, Meng; Chen, Yanhua; Wang, Ning; Wang, Ting; Sun, Mingliang; Yu, Donghong; Yang, Renqiang

    2015-06-24

    A new two-dimensional (2D) conjugated small molecule, namely DCA3TBDTP, with an alkoxyphenyl substituted benzo[1,2-b:4,5-b']dithiophene (BDT) unit as the central core, octyl cyanoacetate as the end-capped groups and terthiophene as the ?-linked bridge, was designed and synthesized for solution-processed organic solar cells (OSCs) as an electron donor material, in which an alkoxyphenyl group was introduced as a weak electron-donating side chain of the BDT moiety. The DCA3TBDTP molecule exhibited good solubility, a deep highest occupied molecular orbital (HOMO) level (-5.25 eV), an appropriate optical band-gap (1.82 eV) and a high decomposition temperature (362 °C). By applying the simple solution spin-coating fabrication process, the bulk heterojunction (BHJ) OSCs based on DCA3TBDTP and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) exhibited a good power conversion efficiency (PCE) of 4.51% with a high open-circuit voltage (Voc) of 0.90 V when thermal annealing at only 70 °C. PMID:26077329

  12. Study of PCB destruction efficiency and performance for a coal fired utility boiler. Volume 2. Test protocol. Final report Mar 80-May 82

    SciTech Connect

    Whitmore, F.C.; Barden, J.D.

    1983-10-01

    As a result of the actions of the Environmental Protection Agency (EPA) in banning the manufacture of PCBs and in requiring that PCBs and PCB contaminated material still in service be withdrawn as soon as is practical, there is a large and growing reservoir of PCB-contaminated hydrocarbons in the United States. In any case, many of these contaminated materials possess significant energy content and therefore could serve as fuel for some industrial processes. In this era of very high fuel costs, there is great demand for PCB-contaminated materials to be used as fuel. A further impetus in this direction is the fact that the PCB Disposal Regulations (referred to herein as the Regulations) specify that incineration is the preferred method of disposal of PCBs and of PCB-contaminated materials. In view of these considerations, it is highly desirable that a series of co-firing experiments be carried out on a coal-fired high efficiency power boiler. Such a test series is described in this document.

  13. Glary Utilities

    NSDL National Science Digital Library

    2008-01-01

    Glary Utilities offers this free application to help users improve their system's performance and also protect their privacy. After installing the application, users can remove and back up faculty registry entries, along with offering a secure file deletion feature. This version is compatible with computers running Windows 98 and newer.

  14. BIOMASS UTILIZATION

    EPA Science Inventory

    The biomass utilization task consists of the evaluation of a biomass conversion technology including research and development initiatives. The project is expected to provide information on co-control of pollutants, as well as, to prove the feasibility of biomass conversion techn...

  15. Residual feed intake as a feed efficiency selection tool and its relationship with feed intake, performance and nutrient utilization in Murrah buffalo calves.

    PubMed

    Subhashchandra Bose, Bisitha Kattiparambil; Kundu, Shivlal Singh; Tho, Nguyen Thi Be; Sharma, Vijay Kumar; Sontakke, Umesh Balaji

    2014-04-01

    Residual feed intake (RFI) is the difference between the actual and expected feed intake of an animal based on its body weight and growth rate over a specific period. The objective of this study was to determine the RFI of buffalo calves using residuals from appropriate linear regression models involving dry matter intake (DMI), average daily gain (ADG) and mid-test metabolic body weight. Eighteen male Murrah buffalo calves of 5-7 months were selected and fed individually. A feeding trial using ad libitum feeding of total mixed ration (TMR, concentrate/roughage = 40:60) was conducted for 52 days in which the daily DMI, weekly body weight (BW) and growth rate of the calves were monitored. RFI of calves ranged from -0.20 to +0.23 kg/day. Mean DMI (in grams per kilogram of BW(0.75)) during the feeding trial period was significantly (P < 0.05) lower in low RFI group (79.66 g/kg BW(0.75)) compared to high RFI (87.74 g/kg BW(0.75)). Average initial BW, final BW and mid-test BW(0.75) did not differ (P > 0.05) between low and high RFI groups. Over the course of a trial period, low RFI group animals consumed 10% less feed compared to high RFI group of animals, yet performed in a comparable manner in terms of growth rate. Metabolizable energy for maintenance (MEm) was found to be significantly (P < 0.05) lower in low RFI group (13.54 MJ/100 kg BW) as compared to that of high RFI group (15.56 MJ/100 kg BW). The present study indicates that RFI is a promising selection tool for the selection of buffaloes for increased feed efficiency. PMID:24563229

  16. Improving the efficiency of feed utilization in poultry by selection. 2. Genetic parameters of excretion traits and correlations with anatomy of the gastro-intestinal tract and digestive efficiency

    PubMed Central

    2011-01-01

    Background Poultry production has been widely criticized for its negative environmental impact related to the quantity of manure produced and to its nitrogen and phosphorus content. In this study, we investigated which traits related to excretion could be used to select chickens for lower environmental pollution. The genetic parameters of several excretion traits were estimated on 630 chickens originating from 2 chicken lines divergently selected on apparent metabolisable energy corrected for zero nitrogen (AMEn) at constant body weight. The quantity of excreta relative to feed consumption (CDUDM), the nitrogen and phosphorus excreted, the nitrogen to phosphorus ratio and the water content of excreta were measured, and the consequences of such selection on performance and gastro-intestinal tract (GIT) characteristics estimated. The genetic correlations between excretion, GIT and performance traits were established. Results Heritability estimates were high for CDUDM and the nitrogen excretion rate (0.30 and 0.29, respectively). The other excretion measurements showed low to moderate heritability estimates, ranging from 0.10 for excreta water content to 0.22 for the phosphorus excretion rate. Except for the excreta water content, the CDUDM was highly correlated with the excretion traits, ranging from -0.64 to -1.00. The genetic correlations between AMEn or CDUDM and the GIT characteristics were very similar and showed that a decrease in chicken excretion involves an increase in weight of the upper part of the GIT, and a decrease in the weight of the small intestine. Conclusion In order to limit the environmental impact of chicken production, AMEn and CDUDM seem to be more suitable criteria to include in selection schemes than feed efficiency traits. PMID:21846409

  17. Feasibility Study of Coexistence between Spread Spectrum and Analog Broadcasting Systems

    E-print Network

    Vouyioukas, Demosthenes

    of the concept. Keywords-Spread Spectrum; Direct Sequence; Analog FM; Protection Ratio; Carrier another. The spectrum overlay between direct sequence Spread Spectrum system and radio services can narrowband FM broadcasting system. The overlaid Spread Spectrum (SS) system is assumed to utilize direct

  18. Increased Photovoltaic Power Output via Diffractive Spectrum Separation

    NASA Astrophysics Data System (ADS)

    Kim, Ganghun; Dominguez-Caballero, Jose A.; Lee, Howard; Friedman, Daniel J.; Menon, Rajesh

    2013-03-01

    In this Letter, we report the preliminary demonstration of a new paradigm for photovoltaic power generation that utilizes a broadband diffractive-optical element (BDOE) to efficiently separate sunlight into laterally spaced spectral bands. These bands are then absorbed by single-junction photovoltaic cells, whose band gaps correspond to the incident spectral bands. We designed such BDOEs by utilizing a modified version of the direct-binary-search algorithm. Gray scale lithography was used to fabricate these multilevel optics. They were experimentally characterized with an overall optical efficiency of 70% over a wavelength range of 350-1100 nm, which was in excellent agreement with simulation predictions. Finally, two prototype devices were assembled: one with a pair of copper indium gallium selenide based photovoltaic devices, and another with GaAs and c-Si photovoltaic devices. These devices demonstrated an increase in output peak electrical power of ˜42% and ˜22%, respectively, under white-light illumination. Because of the optical versatility and manufacturability of the proposed BDOEs, the reported spectrum-splitting approach provides a new approach toward low-cost solar power.

  19. Increased photovoltaic power output via diffractive spectrum separation.

    PubMed

    Kim, Ganghun; Dominguez-Caballero, Jose A; Lee, Howard; Friedman, Daniel J; Menon, Rajesh

    2013-03-22

    In this Letter, we report the preliminary demonstration of a new paradigm for photovoltaic power generation that utilizes a broadband diffractive-optical element (BDOE) to efficiently separate sunlight into laterally spaced spectral bands. These bands are then absorbed by single-junction photovoltaic cells, whose band gaps correspond to the incident spectral bands. We designed such BDOEs by utilizing a modified version of the direct-binary-search algorithm. Gray scale lithography was used to fabricate these multilevel optics. They were experimentally characterized with an overall optical efficiency of 70% over a wavelength range of 350-1100 nm, which was in excellent agreement with simulation predictions. Finally, two prototype devices were assembled: one with a pair of copper indium gallium selenide based photovoltaic devices, and another with GaAs and c-Si photovoltaic devices. These devices demonstrated an increase in output peak electrical power of ? 42% and ? 22%, respectively, under white-light illumination. Because of the optical versatility and manufacturability of the proposed BDOEs, the reported spectrum-splitting approach provides a new approach toward low-cost solar power. PMID:25166805

  20. ENERGY EFFICIENT SYSTEM DESIGN AND UTILIZATION

    E-print Network

    Simunic, Tajana

    the battery lifetime in portable systems, as well as to reduce the operational costs (e.g. cost of electricity by scaling processor frequency and voltage depending on the needs of the system. Finally, I develop a modular power management (DPM) algorithms aim to reduce the energy consumption at the system level

  1. Nanocrystalline dye-sensitized solar cell/copper indium gallium selenide thin-film tandem showing greater than 15% conversion efficiency

    NASA Astrophysics Data System (ADS)

    Liska, P.; Thampi, K. R.; Grätzel, M.; Brémaud, D.; Rudmann, D.; Upadhyaya, H. M.; Tiwari, A. N.

    2006-05-01

    Multijunction stacked (tandem) solar cells can increase the overall photovoltaic conversion efficiency by optimal utilization of the solar spectrum in individual cells. We demonstrate that a photovoltaic tandem cell comprising a nanocrystalline dye-sensitized solar cell as a top cell for high-energy photons and a copper indium gallium selenide thin-film bottom cell for lower-energy photons produces AM 1.5 solar to electric conversion efficiencies greater than 15%.

  2. Lightweight, broad-band spectrum analyzer

    NASA Technical Reports Server (NTRS)

    Crook, G. M.

    1972-01-01

    Spectrum analyzer, utilizing techniques similar to those used to classify energy levels of nuclear particles, is incorporated into electric field detector. Primary advantage is ability to perform qualitative broad-band frequency analysis over a large dynamic amplitude range with minimum weight and electrical power requirements.

  3. SAW correlator spread spectrum receiver

    DOEpatents

    Brocato, Robert W

    2014-04-01

    A surface acoustic wave (SAW) correlator spread-spectrum (SS) receiver is disclosed which utilizes a first demodulation stage with a chip length n and a second demodulation stage with a chip length m to decode a transmitted SS signal having a code length l=n.times.m which can be very long (e.g. up to 2000 chips or more). The first demodulation stage utilizes a pair of SAW correlators which demodulate the SS signal to generate an appropriate code sequence at an intermediate frequency which can then be fed into the second demodulation stage which can be formed from another SAW correlator, or by a digital correlator. A compound SAW correlator comprising two input transducers and a single output transducer is also disclosed which can be used to form the SAW correlator SS receiver, or for use in processing long code length signals.

  4. In situ growth of NiCo2S4 nanotube arrays on Ni foam for supercapacitors: Maximizing utilization efficiency at high mass loading to achieve ultrahigh areal pseudocapacitance

    NASA Astrophysics Data System (ADS)

    Chen, Haichao; Jiang, Jianjun; Zhang, Li; Xia, Dandan; Zhao, Yuandong; Guo, Danqing; Qi, Tong; Wan, Houzhao

    2014-05-01

    Self-standing NiCo2S4 nanotube arrays have been in situ grown on Ni foam by the anion-exchange reaction and directly used as the electrode for supercapacitors. The NiCo2S4 nanotube in the arrays effectively reduces the inactive material and increases the electroactive surface area because of the ultrathin wall, which is quite competent to achieve high utilization efficiency at high electroactive materials mass loading. The NiCo2S4 nanotube arrays hybrid electrode exhibits an ultrahigh specific capacitance of 14.39 F cm-2 at 5 mA cm-2 with excellent rate performance (67.7% retention for current increases 30 times) and cycling stability (92% retention after 5000 cycles) at a high mass loading of 6 mg cm-2. High areal capacitance (4.68 F cm-2 at 10 mA cm-2), high energy density (31.5 Wh kg-1 at 156.6 W kg-1) and high power density (2348.5 W kg-1 at 16.6 Wh kg-1) can be achieved by assembling asymmetric supercapacitor with reduced graphene oxide at a total active material mass loading as high as 49.5 mg. This work demonstrates that NiCo2S4 nanotube arrays structure is a superior electroactive material for high-performance supercapacitors even at a mass loading of potential application-specific scale.

  5. Wideband digital spectrum analyzer

    NASA Technical Reports Server (NTRS)

    Morris, G. A., Jr.; Wilck, H. C.

    1979-01-01

    Modular spectrum analyzer consisting of RF receiver, fast fourier transform spectrum analyzer, and data processor samples stochastic signals in 220 channels. Construction reduces design and fabrication costs of assembled unit.

  6. Computing partial DFT for comb spectrum evaluation

    Microsoft Academic Search

    Shousheng He; M. Torkelson

    1996-01-01

    A comb spectrum evaluation problem arises in the (de)modulation for orthogonal frequency division multiplexing-based (OFDM-based) multichannel communication system. Efficient algorithms for this special type of partial discrete Fourier transform (DFT) computation are studied. For an M-component comb spectrum evaluation with transform length N, it is shown that only O(N+MlogM) multiplications are needed, compared with O(NlogM) multiplications necessary for a narrowband

  7. Optimization in spectrum-sliced optical networks

    NASA Astrophysics Data System (ADS)

    Day Rosario Assis, Karcius; Ferreira dos Santos, Alex; Almeida, Raul C.

    2013-12-01

    Current communication in optical networks presents a wide range of granularities, making it hard to use the optical spectrum efficiently under the WDM framework. In Spectrum Sliced Optical Networks, the WDM rigid frequency grid is replaced by a more flexible structure, in which the spectrum is organized in frequency slots, and each traffic flow is assigned to an appropriate set of contiguous slots. The classical Routing and Wavelength Assignment (RWA) problem is then replaced by a Routing and Spectrum assignment (RSA) problem. This paper addresses an iterativa approach to balance the network load during the routing decision in Spectrum-Elastic Optical Path Networks. We have built numerical examples to illustrate the performance of our routing approach. Comparisons to other routing techniques show that our approach mitigates the lightpath requests blocking probability.

  8. Spread spectrum mobile radio communications

    NASA Astrophysics Data System (ADS)

    Gupta, S. C.

    1982-12-01

    In this report, we analyze the performance of frequency-hopped spread-spectrum systems under mobile radio channel conditions. Because of its good spectrum-efficiency, frequency-hopped systems seen to be natural candidates for mobile telephony in the near future. We analyze mainly the Frequency-Hopped-Multilevel Frequency Shift-Keyed (FH-MFSK) System, the reason being the established superiority of FH-MFSK over the other modulation, namely the Frequency-Hopped Differential Phase Shift Keyed system (FH-DPSK), under identical conditions. Our new results include the spectrum efficiency analysis of FH-MFSK for various bandwidths of interest, the performance analysis of FH-MFSK under the influence of log-normal shadowing and Rayleigh fading, the possible performance improvement with the inclusion of a small number of space-diversity branches to combat the losses due to fading, a preliminary analysis of the occurrence of burst errors in FH systems, the amount of degradation due to the users operating in the adjacent cells and a possible power control scheme to mitigate these effects and finally a result which establishes the near-equivalent performance of the hard-limited and the likelihood receivers under Rayleigh fading and multi-user interference conditions.

  9. Simplified Digital Spectrum Analyzer

    NASA Technical Reports Server (NTRS)

    Cole, Steven W.

    1992-01-01

    Spectrum analyzer computes approximate cross-correlations between noisy input signal and reference signal of known frequency, yielding measure of amplitude of sinusoidal component of input. Complexity and power consumed less than other digital spectrum analyzers. Performs no multiplications, and because processes data on each frequency independently, focuses on narrow spectral range without processing data on rest of spectrum.

  10. Allocating dynamic time-spectrum blocks in cognitive radio networks

    Microsoft Academic Search

    Yuan Yuan; Paramvir Bahl; Ranveer Chandra; Thomas Moscibroda; Yunnan Wu

    2007-01-01

    A number of studies have shown the abundance of unused spectrum in the TV bands. This is in stark contrast to the overcrowding of wireless devices in the ISM bands. A recent trend to alleviate this disparity is the design of Cog- nitive Radios, which constantly sense the spectrum and op- portunistically utilize unused frequencies in the TV bands. In

  11. Partial Cooperation for Spectrum Sharing in Cognitive Radio Network

    E-print Network

    Paris-Sud XI, Université de

    Partial Cooperation for Spectrum Sharing in Cognitive Radio Network Lok Man Law1, Fen Hou2, Jianwei-- In this paper, we consider a cognitive radio network where secondary users may have different sets of available that many licensed radio spectrums are heavily under-utilized. Cognitive radio technology can improve

  12. Spread spectrum microwave bistatic intrusion detection sensor performance update

    SciTech Connect

    Blattman, D.A.; Schilb, W.A.

    1986-01-01

    A new generation of microwave intrusion detection systems that utilizes spread spectrum techniques has been developed. Advances in Jamming Margin, interference rejection and code acquisition are reported. Spread spectrum techniques have been restricted to military communications and radar applications until recent rulings by the FCC. This paper describes the performance obtained in a practical production system that is available ''off-the-shelf''.

  13. Compressed Air Supply Efficiency 

    E-print Network

    Joseph, B.

    2004-01-01

    this as a benchmarking tool, and are now involved in studying the compressor systems in several plants. Utilities and regulatory agencies could quantify system efficiencies and develop statistical histograms for a geographical area and track progress...

  14. Applying Improved Efficiency Transformers 

    E-print Network

    Haggerty, N. K.; Malone, T. P.

    1998-01-01

    that manufacturers utilize to reduce transformer losses are presented. Investment guidelines are provided for performing an economic evaluation and determining if an improved efficiency transformer can be justified. The decision to spend additional capital dollars...

  15. An Approximate Truthfulness Motivated Spectrum Auction for Dynamic Spectrum Access

    E-print Network

    Zhou, Yuanyuan

    An Approximate Truthfulness Motivated Spectrum Auction for Dynamic Spectrum Access Qinhui Wang, China Institute of Computer Science, University of Goettingen, Germany Abstract--Secondary Spectrum Auction (SSA) has been pro- posed as an effective approach to design spectrum sharing mechanism

  16. Ion-thruster propellant utilization

    NASA Technical Reports Server (NTRS)

    Kaufman, H. R.

    1971-01-01

    The evaluation and understanding of maximum propellant utilization, with mercury used as the propellant are presented. The primary-electron region in the ion chamber of a bombardment thruster is analyzed at maximum utilization. The results of this analysis, as well as experimental data from a range of ion-chamber configurations, show a nearly constant loss rate for unionized propellant at maximum utilization over a wide range of total propellant flow rate. The discharge loss level of 1000 eV/ion was used as a definition of maximum utilization, but the exact level of this definition has no effect on the qualitative results and little effect on the quantitative results. There are obvious design applications for the results of this investigation, but the results are particularly significant whenever efficient throttled operation is required.

  17. Revenue Maximization in Spectrum Auctions for Dynamic Spectrum Access

    E-print Network

    Teneketzis, Demosthenis

    1 Revenue Maximization in Spectrum Auctions for Dynamic Spectrum Access Ali Kakhbod, Ashutosh maximization problems in auctions for dynamic spectrum access. We consider the frequency division and spread spectrum methods of dynamic spectrum shar- ing. In the frequency division method, a primary spectrum user

  18. SPECTRUM OPPORTUNITY AND INTERFERENCE CONSTRAINT IN OPPORTUNISTIC SPECTRUM ACCESS

    E-print Network

    Islam, M. Saif

    SPECTRUM OPPORTUNITY AND INTERFERENCE CONSTRAINT IN OPPORTUNISTIC SPECTRUM ACCESS Qing Zhao@ece.ucdavis.edu ABSTRACT In this paper, we study two important concepts in opportunis- tic spectrum access: spectrum intuitive terms central to opportunistic spectrum access. Their implications in spectrum opportunity

  19. Competition with Dynamic Spectrum Leasing Lingjie Duan, Jianwei Huang, and Biying Shou

    E-print Network

    Huang, Jianwei

    spectrum to a third This work is supported by the Competitive Earmarked Research Grants (Project Number1 Competition with Dynamic Spectrum Leasing Lingjie Duan, Jianwei Huang, and Biying Shou Department.shou@cityu.edu.hk Abstract--Dynamic spectrum leasing can greatly enhance the spectrum efficiency and encourage more flexible

  20. Adaptive channel allocation spectrum etiquette for cognitive radio networks

    Microsoft Academic Search

    Nie Nie; Cristina Comaniciu

    2005-01-01

    In this work, we propose a game theoretic framework to analyze the behavior of cognitive radios for distributed adaptive channel allocation. We define two different objective functions for the spectrum sharing games, which capture the utility of selfish users and cooperative users, respectively. Based on the utility definition for cooperative users, we show that the channel allocation problem can be

  1. Adaptive Channel Allocation Spectrum Etiquette for Cognitive Radio Networks

    Microsoft Academic Search

    Nie Nie; Cristina Comaniciu

    2006-01-01

    In this work, we propose a game theoretic frame- work to analyze the behavior of cognitive radios for distributed adaptive channel allocation. We define two different objective functions for the spectrum sharing games, which capture the utility of selfish users and cooperative users, respectively. Based on the utility definition for cooperative users, we show that the channel allocation problem can

  2. Synthesis of artificial spectrum-compatible seismic accelerograms

    NASA Astrophysics Data System (ADS)

    Vrochidou, E.; Alvanitopoulos, P. F.; Andreadis, I.; Elenas, A.; Mallousi, K.

    2014-08-01

    The Hilbert-Huang transform is used to generate artificial seismic signals compatible with the acceleration spectra of natural seismic records. Artificial spectrum-compatible accelerograms are utilized instead of natural earthquake records for the dynamic response analysis of many critical structures such as hospitals, bridges, and power plants. The realistic estimation of the seismic response of structures involves nonlinear dynamic analysis. Moreover, it requires seismic accelerograms representative of the actual ground acceleration time histories expected at the site of interest. Unfortunately, not many actual records of different seismic intensities are available for many regions. In addition, a large number of seismic accelerograms are required to perform a series of nonlinear dynamic analyses for a reliable statistical investigation of the structural behavior under earthquake excitation. These are the main motivations for generating artificial spectrum-compatible seismic accelerograms and could be useful in earthquake engineering for dynamic analysis and design of buildings. According to the proposed method, a single natural earthquake record is deconstructed into amplitude and frequency components using the Hilbert-Huang transform. The proposed method is illustrated by studying 20 natural seismic records with different characteristics such as different frequency content, amplitude, and duration. Experimental results reveal the efficiency of the proposed method in comparison with well-established and industrial methods in the literature.

  3. Optical wireless applications: a solution to ease the wireless airwaves spectrum crunch

    NASA Astrophysics Data System (ADS)

    Kavehrad, M.

    2013-01-01

    Demands by the communications industry for greater and greater bandwidth push the capability of conventional wireless technology. Part of the Radio Spectrum that is suitable for mobility is very limited. Higher frequency waves above 30 GHz tend to travel only a few miles or less and generally do not penetrate solid materials very well. This offers a sustainable solution for the current Spectrum Crunch in the lower microwave bands. One mission of this paper is to demonstrate practical and usable networks that can select a self-limiting link distance, allowing spectrum reuse. The motivation for operators of such bands to actually choose to self-limit is that by doing so, they improve the signal-tonoise against competing users at a lower cost than trying to overcome interference. These characteristics of wave propagation are not necessarily disadvantageous as they enable more densely packed communications links. Thus, high frequencies can provide very efficient spectrum utilization through "selective spectrum reuse", and naturally increase the security of transmissions. Optical systems and networks offer a far greater bandwidth. This means new devices and systems have to be developed. Semiconductor Light Emitting Diode (LED) is considered to be the future primary lighting source for buildings, automobiles and aircrafts. LED provides higher energy efficiency compared to incandescent and fluorescent light sources and it will play a major role in the global reduction of carbon dioxide emissions, as a consequence of the significant energy savings. Lasers are also under investigation for similar applications. These core devices have the potential to revolutionize how we use light, including not only for illumination, but as well; for communications, sensing, navigation, positioning, surveillance, and imaging.

  4. School Focused Utility Programs in Texas 

    E-print Network

    Santos, B.; Negley, M.

    2012-01-01

    ? 2011 CLEAResult ? All rights reserved. School Focused Utility Programs in Texas ? 2011 CLEAResult ? All rights reserved. School and Local Government programs on behalf of: ? 2011 CLEAResult ? All rights reserved. Overview ? Tagos... and CLEAResult ? energy efficiency program implementers for utilities in Texas ? Who we are and what we do ? Energy Efficiency (EE) opportunities in schools ? Eligible EE Measures ? Ineligible EE measures ? Resources to help ? Educational Facilities...

  5. The Semantics of SPECTRUM

    Microsoft Academic Search

    Radu Grosu; Franz Regensburger

    1993-01-01

    Abstract. The Spectrum project concentrates on the process of devel-oping well-structured, precise system speci cations. Spectrum is a spec-i cation language, with a deduction calculus and a development method-ology. An informal presentation of the Spectrum language with many examples illustrating its properties is given in [2, 3]. The purpose of this article is to describe its formal semantics.

  6. Quantum Spread Spectrum Communication

    SciTech Connect

    Humble, Travis S [ORNL

    2011-01-01

    We show that communication of single-photon quantum states in a multi-user environment is improved by using spread spectrum communication techniques. We describe a framework for spreading, transmitting, despreading, and detecting single-photon spectral states that mimics conventional spread spectrum techniques. We show in the cases of inadvertent detection, unintentional interference, and multi-user management, that quantum spread spectrum communications may minimize receiver errors by managing quantum channel access.

  7. Cosmic Ray Spectrum in Supernova Remnant Shocks

    NASA Astrophysics Data System (ADS)

    Kang, Hyesung

    According to kinetic simulations of diffusive shock acceleration (DSA) in Type Ia supernova remnants (SNRs) expanding into a uniform interstellar medium (ISM), the preshock gas tem-perature is the primary parameter that governs the cosmic ray (CR) acceleration efficiency and energy spectrum, while the CR injection rate is a secondary parameter. For SNRs in the warm ISM, if the injection fraction is larger than 10-4 , the DSA is efficient enough to convert more than 20 % of the SN explosion energy into CRs and the accelerated CR spectrum exhibits a concave curvature flattening to E -1.6 . Such a flat source spectrum near the knee energy, how-ever, may not be reconciled with the CR spectrum observed at Earth. On the other hand, SNRs in the hot ISM, with an injection fraction smaller than 10-4 , are inefficient accelerators with less than 10 energy getting converted to CRs. Also the shock structure is almost test-particle like and the ensuing CR spectrum can be steeper than E -2 . With amplified magnetic field strength of order of 30microG, Alfven waves generated by the streaming instability may drift upstream fast enough to make the modified test-particle power-law as steep as E -2.3 , which is more consistent with the observed CR spectrum.

  8. Exact performance analytical model for spectrum allocation in flexible grid optical networks

    NASA Astrophysics Data System (ADS)

    Yu, Yiming; Zhang, Jie; Zhao, Yongli; Li, Hui; Ji, Yuefeng; Gu, Wanyi

    2014-03-01

    Dynamic flexible grid optical networks have gained much attention because of the advantages of high spectrum efficiency and flexibility, while the performance analysis will be more complex compared with fixed grid optical networks. An analytical Markov model is first presented in the paper, which can exactly describe the stochastic characteristics of the spectrum allocation in flexible grid optical networks considering both random-fit and first-fit resource assignment policies. We focus on the effect of spectrum contiguous constraint which has not been systematically studied in respect of mathematical modeling, and three major properties of the model are presented and analyzed. The model can expose key performance features and act as the foundation of modeling the Routing and Spectrum Assignment (RSA) problem with diverse topologies. Two heuristic algorithms are also proposed to make it more tractable. Finally, several key parameters, such as blocking probability, resource utilization rate and fragmentation rate are presented and computed, and the corresponding Monte Carlo simulation results match closely with analytical results, which prove the correctness of this mathematical model.

  9. Utility restructuring: Boon or bane for renewables?

    SciTech Connect

    Hochanadel, J.R.; Aitken, D.W.

    1996-11-01

    This article describes the challenges and opportunities for the renewables industry as electric utility restructuring begins. Topics include the following: the changes in the electric power industry and what lead to restructuring; the uncertain future and the issues involved (demand side management, energy efficiency programs, low income assistance, research in the public interest, commercialization of renewables); position of the ASES on utility restructuring.

  10. Autism spectrum disorder

    MedlinePLUS

    Autism; Autistic disorder; Asperger syndrome; Childhood disintegrative disorder; Pervasive developmental disorder ... Autism spectrum disorder (ASD) is a physical condition linked to abnormal biology and chemistry in the brain. ...

  11. Ionospheric wave spectrum measurements

    NASA Technical Reports Server (NTRS)

    Harker, K. J.; Ilic, D. B.; Crawford, F. W.

    1979-01-01

    The local spectrum S(k, omega) of either potential or electron-density fluctuations can be used to determine macroscopic-plasma characteristics such as the local density and temperature, transport coefficients, and drift current. This local spectrum can be determined by measuring the cross-power spectrum. The paper examines the practicality of using the cross-power spectrum analyzer on the Space Shuttle to measure ionospheric parameters. Particular attention is given to investigating the integration time required to measure the cross-power spectral density to a desired accuracy.

  12. Quantum dot light-emitting devices with electroluminescence tunable over the entire visible spectrum.

    PubMed

    Anikeeva, Polina O; Halpert, Jonathan E; Bawendi, Moungi G; Bulovi?, Vladimir

    2009-07-01

    Improvements in quantum dot light-emitting device (QD-LED) performance are achieved by the choice of organic charge transporting layers, by use of different colloidal QDs for the different parts of the visible spectrum, and by utilizing a recently demonstrated robust QD deposition method. Spectrally narrow electroluminescence of our QD-LEDs is tuned over the entire visible wavelength range from lambda = 460 nm (blue) to lambda = 650 nm (deep red). By printing close-packed monolayers of different QD types inside an identical QD-LED structure, we demonstrate that different color QD-LEDs with QDs of different chemistry can be fabricated on the same substrate. We discuss mechanisms responsible for efficiency increase for green (4-fold) and orange (30%) QD-LEDs as compared to previous reports and outline challenges associated with achieving high-efficiency blue QD-LEDs. PMID:19514711

  13. A Comprehensive Book on Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Mohammadi, Mohammad-Reza, Ed.

    2011-01-01

    The aim of the book is to serve for clinical, practical, basic and scholarly practices. In twentyfive chapters it covers the most important topics related to Autism Spectrum Disorders in the efficient way and aims to be useful for health professionals in training or clinicians seeking an update. Different people with autism can have very different…

  14. Broadband Acousto-Optic Spectrum Analysis

    Microsoft Academic Search

    D. L. Hecht

    1973-01-01

    Detailed experimental and theoretical results a re presented characterizing the real-time optical Fourier spectrum analysis of a wide band of electrical signals by means of acousto-optic diffraction. Results include bandwidth, resolution, intermodulation, cross modulation, sensitivity, dynamic range, efficiency, and pulse response.

  15. Power spectrum with auxiliary fields in de Sitter space

    NASA Astrophysics Data System (ADS)

    Mohsenzadeh, M.; Tanhayi, M. R.; Yusofi, E.

    2014-06-01

    We use the auxiliary fields and (excited-) de Sitter solutions to study the standard power spectrum of primordial fluctuations of a scalar field in the early universe. The auxiliary fields are the negative norm solutions of the field equation and as is shown, with a fixed boundary condition, utilizing these states results in a finite power spectrum without any infinity. The power spectrum is determined by the de Sitter solutions up to some corrections and the space-time symmetry is not broken in this point of view. The modulation to the power spectrum is of order , where is the Hubble parameter and is the energy scale, e.g., the Planck scale.

  16. Tan F. Wong: Spread Spectrum & CDMA 2. Intro. Spread Spectrum Introduction to Spread Spectrum

    E-print Network

    Wong, Tan F.

    Tan F. Wong: Spread Spectrum & CDMA 2. Intro. Spread Spectrum Chapter 2 Introduction to Spread Spectrum Communications As discussed in Chapter 0, a spread spectrum modulation produces a transmitted spectrum much wider than the minimum bandwidth required. There are many ways to generate spread spectrum

  17. Power Electronics for Distributed Energy Systems and Transmission and Distribution Applications: Assessing the Technical Needs for Utility Applications

    SciTech Connect

    Tolbert, L.M.

    2005-12-21

    Power electronics can provide utilities the ability to more effectively deliver power to their customers while providing increased reliability to the bulk power system. In general, power electronics is the process of using semiconductor switching devices to control and convert electrical power flow from one form to another to meet a specific need. These conversion techniques have revolutionized modern life by streamlining manufacturing processes, increasing product efficiencies, and increasing the quality of life by enhancing many modern conveniences such as computers, and they can help to improve the delivery of reliable power from utilities. This report summarizes the technical challenges associated with utilizing power electronics devices across the entire spectrum from applications to manufacturing and materials development, and it provides recommendations for research and development (R&D) needs for power electronics systems in which the U.S. Department of Energy (DOE) could make a substantial impact toward improving the reliability of the bulk power system.

  18. On the ice nucleation spectrum

    NASA Astrophysics Data System (ADS)

    Barahona, D.

    2011-11-01

    This work presents a novel formulation of the ice nucleation spectrum, i.e. the function relating the ice crystal concentration to cloud formation conditions and aerosol properties. The new formulation relies on a statistical view of the ice nucleation process and explicitly accounts for the dependency of the ice crystal concentration on temperature, supersaturation, cooling rate, and particle size, and, in the case of heterogeneous ice nucleation, on the distributions of particle area and surface composition. The new formulation is used to generate ice nucleation parameterizations for the homogeneous freezing of cloud droplets and the heterogeneous deposition ice nucleation on dust and soot ice nuclei. For homogeneous freezing, it was found that by increasing the dispersion in the droplet volume distribution the fraction of supercooled droplets in the population increases. For heterogeneous ice nucleation it was found that ice nucleation on efficient ice nuclei (IN) shows features consistent with the singular hypothesis (characterized by a lack of temporal dependency of the ice nucleation spectrum) whereas less efficient IN tend to display stochastic behavior. Analysis of empirical nucleation spectra suggested that inferring the aerosol heterogeneous ice nucleation properties from measurements of the onset supersaturation and temperature may carry significant error as the variability in ice nucleation properties within the aerosol population is not accounted for. This work provides a simple and rigorous ice nucleation framework were theoretical predictions, laboratory measurements and field campaign data can be reconciled, and that is suitable for application in atmospheric modeling studies.

  19. Radio frequency spectrum management

    Microsoft Academic Search

    E. J. Sujdak Jr.

    1980-01-01

    This thesis is a study of radio frequency spectrum management as practiced by agencies and departments of the Federal Government. After a brief introduction to the international agency involved in radio frequency spectrum management, the author concentrates on Federal agencies engaged in frequency management. These agencies include the National Telecommunications and Information Administration (NTIA), the Interdepartment Radio Advisory Committee (IRAC),

  20. The Electromagnetic Spectrum

    NSDL National Science Digital Library

    2012-08-03

    This is a lesson about the electromagnetic spectrum. Learners will read two pages of information about the electromagnetic spectrum and answer questions in an accompanying worksheet. This activity is from the Stanford Solar Center's All About the Sun: Sun and Stars activity guide for Grades 5-8 and can also accompany the Stanford Solar Center's Build Your Own Spectroscope activity.

  1. The CMBR spectrum

    SciTech Connect

    Stebbins, A.

    1997-05-01

    Here we give an introduction to the observed spectrum of the Cosmic Microwave Background Radiation (CMBR) and discuss what can be learned about it. Particular attention will be given to how Compton scattering can distort the spectrum of the CMBR. An incomplete bibliography of relevant papers is also provided.

  2. Autism spectrum disorders

    Microsoft Academic Search

    Tony Charman

    2008-01-01

    The term autism spectrum disorders (ASDs) is used to describe a range of neurodevelopmental conditions characterized by impairments in social interaction and communication, and the presence of repetitive and rigid behaviours. Historically, autism was considered a rare condition, but recent studies indicate that the prevalence may be as high as 1% for the broader autism spectrum. The prevalence of autism

  3. Expected Utility Distributions for Flexible, Contingent Execution

    NASA Technical Reports Server (NTRS)

    Bresina, John L.; Washington, Richard

    2000-01-01

    This paper presents a method for using expected utility distributions in the execution of flexible, contingent plans. A utility distribution maps the possible start times of an action to the expected utility of the plan suffix starting with that action. The contingent plan encodes a tree of possible courses of action and includes flexible temporal constraints and resource constraints. When execution reaches a branch point, the eligible option with the highest expected utility at that point in time is selected. The utility distributions make this selection sensitive to the runtime context, yet still efficient. Our approach uses predictions of action duration uncertainty as well as expectations of resource usage and availability to determine when an action can execute and with what probability. Execution windows and probabilities inevitably change as execution proceeds, but such changes do not invalidate the cached utility distributions, thus, dynamic updating of utility information is minimized.

  4. Robustness Performance Analysis of Audio Watermarking Algorithm Based on Direct Sequence Spread Spectrum

    Microsoft Academic Search

    Guang Chen; Senbin Yang; Qian Zhang; Jia Du

    2011-01-01

    To analyze the robustness performance of direct sequence spread spectrum (DSSS) based audio watermarking algorithm theoretically, the fundamental principle of spread spectrum watermarking is analyzed firstly. The communication model of DSSS-based audio watermarking system is designed according to the spread spectrum communication theory. The interrelation between bit error rate (BER) and watermark power and processing gain is revealed by utilizing

  5. Theoretical Analysis of the Coexistence of Direct Sequence Spread Spectrum and Analog FM Systems

    E-print Network

    Vouyioukas, Demosthenes

    Theoretical Analysis of the Coexistence of Direct Sequence Spread Spectrum and Analog FM Systems Spread Spectrum (SS) system is assumed to utilize direct sequence (DS) spreading, using maximal length of a Spread Spectrum system on the existing narrowband FM broadcasting system is presented. The overlaid

  6. Entropy Spectrum of Modified Schwarzschild Black Hole via an Action Invariance

    NASA Astrophysics Data System (ADS)

    Liu, Cheng-Zhou

    2014-09-01

    The entropy spectrum of a modified Schwarzschild black hole in the gravity's rainbow are investigated. By utilizing an action invariance of the black hole with the help of Bohr-Sommerfield quantization rule, the entropy spectrum for the modified black hole are calculated. The result of the equally spaced-entropy spectrum being consistent to the original Bekenstein's spectra is derived.

  7. Dynamic spectrum leasing in cognitive radio networks via primary-secondary user power control games

    Microsoft Academic Search

    Sudharman K. Jayaweera; Tianming Li

    2009-01-01

    Hierarchical dynamic spectrum access (DSA) has received the most attention in recent years as the solution for better spectrum utilization. In this paper, on the other hand, we develop a framework for dynamic spectrum leasing (DSL). Power control in hierarchical DSA networks only involves that of controlling secondary user transmissions. Thus, in game theoretic formulations of power control in cognitive

  8. Eliminating Noise at the Box-fitting Spectrum

    NASA Astrophysics Data System (ADS)

    Boufleur, Rodrigo Carlos; Emilio, Marcelo; Pacheco, Eduardo Janot; de La Reza, Jorge Ramiro; da Rocha, José Carlos

    2014-04-01

    Non gaussian sources of erros need to be taken into consideration when searching for planetary transits. Such phenomena are mostly caused by the impact of high energetic particles on the detector (Pinheiro da Silva et al. 2008). The detection efficiency of transits, therefor, depend significantly on the data quality and the algorithms utilized to deal with these errors sources. In this work we show that a modified detrend algorithm CDA (CoRoT Detrend Algorithm; Mislis et al. 2010) using a robust statistics and an empirical fit, instead of a polynomial one, can eliminate more efficiently gaps in the data and other long-term trends from the light-curve. Using this algorithm enables us to obtain a reconstructed light-curve with better signal-to-noise ratio that allows to improve the detection of exoplanet transits, although long term signals are destroyed. The results show that these modifications lead to an improved BLS (Box-fitting Least Squares; Kovács, Zucker & Mazeh 2002) algorithm spectrum. At the end we have compared our planetary search results with CoRoT (Convection, Rotation and planetary Transits) satellite chromatic light-curves available in the literature.

  9. Entropy spectrum and area spectrum of a modified Schwarzschild black hole via an action invariance

    NASA Astrophysics Data System (ADS)

    Liu, C. Z.; Yu, G. X.

    2015-01-01

    The spectroscopy of a quantum corrected Schwarzschild black hole in the gravity's rainbow is investigated. By utilizing the action invariance of the black hole and with the help of Bohr-Sommerfeld quantization rule, the entropy and area spectrum for the modified black hole are calculated. Here, the quasinormal modes of the black hole are not used. The obtained entropy spectrum is equally spaced and has not dependence on the quantum effects of the spacetime. However, due to the spacetime quantum effects of the modified black hole, the obtained area spectra are not equally spaced and the area spacing depends on the horizon area of the black hole. But, as the same to the entropy spectrum, the area spectrum of the gravity's rainbow is independent of the energy of test particle, although the modified spacetime has the dependence on the particle energy.

  10. Power Spectrum in Krein Space Quantization

    E-print Network

    M. Mohsenzadeh; S. Rouhani; M. V. Takook

    2008-11-06

    The power spectrum of scalar field and space-time metric perturbations produced in the process of inflation of universe, have been presented in this paper by an alternative approach to field quantization namely, Krein space quantization [1,2]. Auxiliary negative norm states, the modes of which do not interact with the physical world, have been utilized in this method. Presence of negative norm states play the role of an automatic renormalization device for the theory.

  11. SALSA: Strategyproof Online Spectrum Admissions for Wireless Networks

    E-print Network

    Li, Xiang-Yang

    -arbitrary-arrival case: the bid values could be arbitrary, but the request arrival sequence is random. We analytically prove that our protocols are strategyproof, and are both approximately social efficient and revenue THE current fixed spectrum allocation scheme leads to significant spectrum white spaces, where many allocated

  12. A Low-Power Single-Weight-Combiner 802.11abg SoC in 0.13 µm CMOS for Embedded Applications Utilizing An Area and Power Efficient Cartesian Phase Shifter and Mixer Circuit

    Microsoft Academic Search

    Ali Afsahi; Jacob J. Rael; Arya Behzad; Michael Pan; Stephen Au; Adedayo Ojo; C. Paul Lee; Seema Butala Anand; Kevin Chien; Stephen Wu; Alireza Zolfaghari; John C. Leete; Long Tran; Keith A. Carter; Mohammad Nariman; Keno Wai-Ki Yeung; Walter Morton; Mark Gonikberg; Mukul Seth; Marcellus Forbes; Jay Pattin; Luis Gutierrez; Sumant Ranganathan; Ning Li; Eric Blecker; Tom Kwan; Mark Chambers; Maryam Rofougaran; Jason Trachewsky; Pieter Van Rooyen

    2008-01-01

    A low-power 802.11abg SoC which achieves the best reported sensitivity as well as lowest reported power consumption and utilizes an extensive array of auto calibrations is reported. This SoC utilizes a two-antenna array receiver to build a single weight combiner (SWC) system. A new signal-path Cartesian phase generation and combination technique is proposed that shifts the RF signal in 22.5deg

  13. Purdue Solar Energy Utilization Laboratory

    SciTech Connect

    Agrawal, Rakesh [Purdue] [Purdue

    2014-01-21

    The objective of this project is to establish and set-up a laboratory that will facilitate research and development of new low-cost and high-efficiency solar energy utilization technologies at Purdue University. The outcome will help spur the creation of solar energy start-up companies and eventually a solar energy industry in Indiana that can help fulfill the growing national demand for solar energy.

  14. Smart radio: spectrum access for first responders

    NASA Astrophysics Data System (ADS)

    Silvius, Mark D.; Ge, Feng; Young, Alex; MacKenzie, Allen B.; Bostian, Charles W.

    2008-04-01

    This paper details the Wireless at Virginia Tech Center for Wireless Telecommunications' (CWT) design and implementation of its Smart Radio (SR) communication platform. The CWT SR can identify available spectrum within a pre-defined band, rendezvous with an intended receiver, and transmit voice and data using a selected quality of service (QoS). This system builds upon previous cognitive technologies developed by CWT for the public safety community, with the goal of providing a prototype mobile communications package for military and public safety First Responders. A master control (MC) enables spectrum awareness by characterizing the radio environment with a power spectrum sensor and an innovative signal detection and classification module. The MC also enables spectrum and signal memory by storing sensor results in a knowledge database. By utilizing a family radio service (FRS) waveform database, the CWT SR can create a new communication link on any designated FRS channel frequency using FM, BPSK, QPSK, or 8PSK modulations. With FM, it supports analog voice communications with legacy hand-held FRS radios. With digital modulations, it supports IP data services, including a CWT developed CVSD-based VoIP protocol. The CWT SR coordinates spectrum sharing between analog primary users and digital secondary users by applying a simple but effective channel-change protocol. It also demonstrates a novel rendezvous protocol to facilitate the detection and initialization of communications links with neighboring SR nodes through the transmission of frequency-hopped rendezvous beacons. By leveraging the GNU Radio toolkit, writing key modules entirely in Python, and utilizing the USRP hardware front-end, the CWT SR provides a dynamic spectrum test bed for future smart and cognitive radio research.

  15. Shuttle spectrum despreader

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The results of the spread spectrum despreader project are reported and three principal products are designed and tested. The products are, (1) a spread spectrum despreader breadboard, (2) associated test equipment consisting of a spectrum spreader and bit reconstruction/error counter and (3) paper design of a Ku-band receiver which would incorporate the despreader as a principal subsystem. The despreader and test set are designed for maximum flexibility. A choice of unbalanced quadriphase or biphase shift keyed data modulation is available. Selectable integration time and threshold voltages on the despreader further lend true usefulness as laboratory test equipment to the delivered hardware.

  16. The Electromagnetic Spectrum: FRONTLINE

    NSDL National Science Digital Library

    2004-02-20

    This video segment adapted from FRONTLINE introduces the electromagnetic spectrum and explains how the various types of electromagnetic waves are distinguished by the amount of energy each wave carries.

  17. Biphoton Spectrum Control

    E-print Network

    K. G. Katamadze; S. P. Kulik

    2011-04-03

    The main methods for controlling the biphoton field, as well as the problems for which the width and the shape of the spectrum of the biphoton field are of decisive importance, are discussed. The method for controlling the spectrum of the spontaneous parametric downconversion of light based on the spatial modulation of the refractive indices of a nonlinear crystal in which the generation of biphotons has been analyzed. Modulation is due to the thermo-optic and electro-optic effects.

  18. Correlation matching approach for spectrum sensing in open spectrum communications

    Microsoft Academic Search

    Ana I. Pérez-Neira; Miguel Angel Lagunas; Miguel Angel Rojas; Petre Stoica

    2009-01-01

    In the new paradigm of open spectrum access, the envisioned radio agility calls for fast and accurate spectrum sensing, this challenges traditional spectral estimation. In this study, we propose three new procedures that are able to sense the known spectrum of the candidate or primary user, fulfilling the requirements of open spectrum scenarios. These procedures are developed by following the

  19. CMB Power Spectrum Estimation via Hierarchical Decomposition

    E-print Network

    O. Doré; L. Knox; A. Peel

    2001-04-27

    We have developed a fast, accurate and generally applicable method for inferring the power spectrum and its uncertainties from maps of the cosmic microwave background (CMB) in the presence of inhomogeneous and correlated noise. For maps with 10 to 100 thousand pixels, we apply an exact power spectrum estimation algorithm to submaps of the data at various resolutions, and then combine the results in an optimal manner. To analyze larger maps efficiently one must resort to sub-optimal combinations in which cross-map power spectrum error correlations are only calculated approximately. We expect such approximations to work well in general, and in particular for the megapixel maps to come from the next generation of satellite missions.

  20. Micro acoustic spectrum analyzer

    DOEpatents

    Schubert, W. Kent; Butler, Michael A.; Adkins, Douglas R.; Anderson, Larry F.

    2004-11-23

    A micro acoustic spectrum analyzer for determining the frequency components of a fluctuating sound signal comprises a microphone to pick up the fluctuating sound signal and produce an alternating current electrical signal; at least one microfabricated resonator, each resonator having a different resonant frequency, that vibrate in response to the alternating current electrical signal; and at least one detector to detect the vibration of the microfabricated resonators. The micro acoustic spectrum analyzer can further comprise a mixer to mix a reference signal with the alternating current electrical signal from the microphone to shift the frequency spectrum to a frequency range that is a better matched to the resonant frequencies of the microfabricated resonators. The micro acoustic spectrum analyzer can be designed specifically for portability, size, cost, accuracy, speed, power requirements, and use in a harsh environment. The micro acoustic spectrum analyzer is particularly suited for applications where size, accessibility, and power requirements are limited, such as the monitoring of industrial equipment and processes, detection of security intrusions, or evaluation of military threats.

  1. IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 29, NO. 4, APRIL 2011 843 Spectrum Trading in Cognitive Radio Networks: A

    E-print Network

    Wang, Xinbing

    IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 29, NO. 4, APRIL 2011 843 Spectrum Trading.e., secondary users, SUs) to access the licensed spectrum. Market-driven spectrum trading is an efficient way to achieve dynamic spectrum accessing/sharing. In this paper, we consider the problem of spectrum trading

  2. Nanocrystalline dye-sensitized solar cell\\/copper indium gallium selenide thin-film tandem showing greater than 15% conversion efficiency

    Microsoft Academic Search

    P. Liska; K. R. Thampi; D. Bre´maud; D. Rudmann; H. M. Upadhyaya; A. N. Tiwari

    2006-01-01

    Multijunction stacked (tandem) solar cells can increase the overall photovoltaic conversion efficiency by optimal utilization of the solar spectrum in individual cells. We demonstrate that a photovoltaic tandem cell comprising a nanocrystalline dye-sensitized solar cell as a top cell for high-energy photons and a copper indium gallium selenide thin-film bottom cell for lower-energy photons produces AM 1.5 solar to electric

  3. Cosmic Ray Spectrum in Supernova Remnant Shocks

    NASA Astrophysics Data System (ADS)

    Kang, Hyesung

    2010-04-01

    We perform kinetic simulations of diffusive shock acceleration (DSA) in Type Ia supernova remnants (SNRs) expanding into a uniform interstellar medium (ISM). Bohm-like diffusion due to self-excited Alfvén waves is assumed,and simple models for Alfvénic drift and dissipation are adopted. Phenomenological models for thermal leakage injection are considered as well. We find that the preshock gas temperature is the primary parameter that governs the cosmic ray (CR) acceleration efficiency and energy spectrum,while the CR injection rate is a secondary parameter. For SNRs in the warm ISM of T_0 ? 10^5K, if the injection fraction is ? ? 10^{-4},the DSA is efficient enough to convert more than 20 % of the SN explosion energy into CRs and the accelerated CR spectrum exhibits a concave curvature flattening to E^{-1.6}, which is characteristic of CR modified shocks. Such a flat source spectrum near the knee energy, however, may not be reconciled with the CR spectrum observed at Earth.On the other hand, SNRs in the hot ISM of T_0? 10^6K with a small injection fraction, ? < 10^{-4}, are inefficient accelerators with less than 10 % of the explosion energy getting converted to CRs. Also the shock structure is almost test-particle like and the ensuing CR spectrum can be steeper than E^{-2}. With amplified magnetic field strength of order of 30?G, Alfvén waves generated by the streaming instability may drift upstream fast enough to make the modified test-particle power-law as steep as E^{-2.3}, which is more consistent with the observed CR spectrum.

  4. Orientation Spectrum Algorithm Development

    NASA Astrophysics Data System (ADS)

    Brianskiy, S. A.; Sidyakin, S. V.; Vizilter, Y. V.

    2015-05-01

    A morphological orientation spectra is proposed. This spectrum describes basic directions of shape parts. Fast discrete-continuous algorithm for computing orientation spectrum is presented. It is based on usage of continuous skeleton that is constructed from polygonal shape contour. A definition for disc orientation map is given. Comparison experiments for binary shapes with the usage of orientation spectra are carried out. Cyclic shift and EMD-L1 distance are used for spectra comparison. The obtained results indicate that the aggregation of the thickness spectra with orientation spectra increases the quality of inter-class recognition.

  5. NREL Spectrum of Innovation

    ScienceCinema

    None

    2013-05-29

    There are many voices calling for a future of abundant clean energy. The choices are difficult and the challenges daunting. How will we get there? The National Renewable Energy Laboratory integrates the entire spectrum of innovation including fundamental science, market relevant research, systems integration, testing and validation, commercialization and deployment. The innovation process at NREL is interdependent and iterative. Many scientific breakthroughs begin in our own laboratories, but new ideas and technologies come to NREL at any point along the innovation spectrum to be validated and refined for commercial use.

  6. Time delay spectrum conditioner

    DOEpatents

    Greiner, Norman R. (Los Alamos, NM)

    1980-01-01

    A device for delaying specified frequencies of a multiple frequency laser beam. The device separates the multiple frequency beam into a series of spatially separated single frequency beams. The propagation distance of the single frequency beam is subsequently altered to provide the desired delay for each specific frequency. Focusing reflectors can be utilized to provide a simple but nonadjustable system or, flat reflectors with collimating and focusing optics can be utilized to provide an adjustable system.

  7. On the Spectrum Handoff for Cognitive Radio Ad Hoc Networks without Common Control Channel

    E-print Network

    Song, Yi

    2011-01-01

    Cognitive radio (CR) technology is a promising solution to enhance the spectrum utilization by enabling unlicensed users to exploit the spectrum in an opportunistic manner. Since unlicensed users are temporary visitors to the licensed spectrum, they are required to vacate the spectrum when a licensed user reclaims it. Due to the randomness of the appearance of licensed users, disruptions to both licensed and unlicensed communications are often difficult to prevent. In this chapter, a proactive spectrum handoff framework for CR ad hoc networks is proposed to address these concerns. In the proposed framework, channel switching policies and a proactive spectrum handoff protocol are proposed to let unlicensed users vacate a channel before a licensed user utilizes it to avoid unwanted interference. Network coordination schemes for unlicensed users are also incorporated into the spectrum handoff protocol design to realize channel rendezvous. Moreover, a distributed channel selection scheme to eliminate collisions a...

  8. Abstract--Flexible spectrum sharing is widely seen to be important feature for the future

    E-print Network

    considered in WINNER project for RRM functionalities implementing flexible spectrum sharing is presentedAbstract--Flexible spectrum sharing is widely seen to be important feature for the future beyond 3G systems. Efficient implementation of spectrum sharing requires novel radio resource management (RRM

  9. Attack Prevention for Collaborative Spectrum Sensing in Cognitive Radio Networks

    E-print Network

    Duan, Lingjie; Huang, Jianwei; Shin, Kang G

    2011-01-01

    Collaborative spectrum sensing can significantly improve the detection performance of secondary unlicensed users (SUs). However, the performance of collaborative sensing is vulnerable to sensing data falsification attacks, where malicious SUs (attackers) submit manipulated sensing reports to mislead the fusion center's decision on spectrum occupancy. Moreover, attackers may not follow the fusion center's decision regarding their spectrum access. This paper considers a challenging attack scenario where multiple rational attackers overhear all honest SUs' sensing reports and cooperatively maximize attackers' aggregate spectrum utilization. We show that, without attack-prevention mechanisms, honest SUs are unable to transmit over the licensed spectrum, and they may further be penalized by the primary user for collisions due to attackers' aggressive transmissions. To prevent such attacks, we propose two novel attack-prevention mechanisms with direct and indirect punishments. The key idea is to identify collisions...

  10. Optimization of rate and efficiency of dietary nitrogen utilization through the use of animal by-products and(or) urea and their effects on nutrient digestion in Holstein steers1

    Microsoft Academic Search

    W. F. Knaus; D. H. Beermann; P. J. Guiroy; M. L. Boehm; D. G. Fox

    2010-01-01

    The objective of this N balance study was to determine the potential for improving the effi- ciency and rate of dietary N utilization in Holstein steers by feeding an amino acid-balanced mixture of animal by-product protein sources in combination with urea. The Beef NRC 1996 Model Level 2 was used to formulate a corn-based (86:14 concentrate-hay) control diet with soybean

  11. Spectrum tailoring of the neutron energy spectrum in the context of delayed neutron detection

    SciTech Connect

    Koehler, William E [Los Alamos National Laboratory; Tobin, Steve J [Los Alamos National Laboratory; Sandoval, Nathan P [Los Alamos National Laboratory; Fensin, Mike L [Los Alamos National Laboratory

    2010-01-01

    For the purpose of measuring plutonium mass in spent fuel, a delayed neutron instrument is of particular interest since, if properly designed, the delayed neutron signal from {sup 235}U is significantly stronger than the signature from {sup 239}Pu or {sup 241}Pu. A key factor in properly designing a delayed neutron instrument is to minimize the fission of {sup 238}U. This minimization is achieved by keeping the interrogating neutron spectrum below {approx} 1 MeV. In the context of spent fuel measurements it is desirable to use a 14 MeV (deuterium and tritium) neutron generator for economic reasons. Spectrum tailoring is the term used to describe the inclusion of material between the 14 MeV neutrons and the interrogated object that lower the neutron energy through nuclear reactions and moderation. This report quantifies the utility of different material combination for spectrum tailoring.

  12. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization DURABILITY OF CAST-CONCRETE PRODUCTS UTILIZING RECYCLED MATERIAL of Engineering and Applied Science THE UNIVERSITY OF WISCONISN-MILWAUKEE #12;Strength and Durability of Cast-Concrete Products Utilizing Recycled Materials Tarun R. Naik, Rudolph N. Kraus, Yoon-Moon Chun, and Bruce R. Ramme

  13. Miscellaneous Mathematical Utilities

    NSDL National Science Digital Library

    Several online mathematical utilities intended for college and university students (math, physics, engineering, etc. students). Numerical utilities to solve (among others): N Equations in N Unknowns, Eigenvalues and Eigenvectors, Roots of Functions, and Numerical Integration. More utilities are constantly being added.

  14. The Frequency Spectrum Radio.

    ERIC Educational Resources Information Center

    Howkins, John, Ed.

    1979-01-01

    This journal issue focuses on the frequency spectrum used in radio communication and on the World Administrative Radio Conference, sponsored by the International Telecommunication Union, held in Geneva, Switzerland, in the fall of 1979. Articles describe the World Administrative Radio Conference as the most important radio communication conference…

  15. Narrowband spread spectrum systems

    Microsoft Academic Search

    K. H. Annecke; M. Ottka

    1984-01-01

    The available military radio frequency bands are covered very densely by the already existing conventional systems and therefore the application of bandwidth widening procedures as antijam measures will be allowed only with small spreading factors within these RF-bands. The problems arising from the random code selection for spread spectrum systems with small spreading factors are discussed. The calculations show the

  16. Social anxiety spectrum

    Microsoft Academic Search

    Liliana Dell’Osso; Paola Rucci; Francesca Ducci; Antonio Ciapparelli; Laura Vivarelli; Marina Carlini; Carla Ramacciotti; Giovanni B. Cassano

    2003-01-01

    The aim of this paper is to provide the prevalence rates of mild, moderate and severe symptoms of social anxiety in a sample of high school students and to analyze gender differences and associated impairment levels within these three levels of severity. Five hundred and twenty students were assessed with the Social Anxiety Spectrum Self-Report (SHY-SR), a questionnaire that explores

  17. Radio spectrum surveillance station

    Microsoft Academic Search

    D. R. Hersey

    1979-01-01

    The paper presents a general and functional description of a low-cost surveillance station designed as the first phase of NASA's program to develop a radio spectrum surveillance capability for deep space stations for identifying radio frequency interference sources. The station described has identified several particular interferences and is yielding spectral signature data which, after cataloging, will serve as a library

  18. Spectrum of analytic continuation

    E-print Network

    David V. Ingerman

    2008-06-03

    I will show that operator of analytic (harmonic) continuation on a lattice graph has a positive spectrum. I use a theorem about positivity of eigenvalues of totally positive matrices. I conjecture that by approximation the similar result holds in continuous case on a plane.

  19. Spread spectrum image steganography

    Microsoft Academic Search

    Lisa M. Marvel; Charles G. Boncelet Jr.; Charles T. Retter

    1999-01-01

    In this paper, we present a new method of digitalsteganography, entitled spread spectrum image steganography(SSIS). Steganography, which means "covered writing" in Greek,is the science of communicating in a hidden manner. Followinga discussion of steganographic communication theory and reviewof existing techniques, the new method, SSIS, is introduced. Thissystem hides and recovers a message of substantial length withindigital imagery while maintaining the

  20. The Spectrum Top

    Microsoft Academic Search

    Dawson Turner

    1895-01-01

    PERHAPS some of your readers may be glad to learn that the curious phenomena of the spectrum top can be shown on a screen to a large audience. It is only necessary to paint the usual black lines and sector on a suitable disc of glass, and then to mount it in a revolving stage which can be rotated in

  1. CMB Power Spectrum Estimation

    E-print Network

    Lloyd Knox; J. Richard Bond; Andrew H. Jaffe

    1997-02-13

    We explore power spectrum estimation in the context of a Gaussian approximation to the likelihood function. Using the Saskatoon data, we estimate the power averaged through a set of ten filters designed to make the errors on the power estimates uncorrelated. We also present an improvement to using the window function, $W_l$, for calculating bandpower estimates.

  2. Charging for Spectrum Use.

    ERIC Educational Resources Information Center

    Geller, Henry; Lampert, Donna

    This paper, the third in a series exploring future options for public policy in the communications and information arenas, argues that the communications spectrum--e.g., public mobile service, private radio, and domestic satellites--is a valuable but limited resource that should benefit all Americans. After a background discussion, it is…

  3. The influence of campus experiences on the level of outness among trans-spectrum and queer-spectrum students.

    PubMed

    Garvey, Jason C; Rankin, Susan R

    2015-01-01

    This study utilized MANOVA and hierarchical multiple regression to examine the relationships between campus experiences and coming-out decisions among trans- and queer-spectrum undergraduates. Findings revealed higher levels of outness/disclosure for cisgender LGBQ women, and more negative perceptions of campus climate, classroom climate, and curriculum inclusivity and higher use of campus resources for trans-spectrum students. Results also revealed that higher levels of outness significantly related to poorer perceptions of campus responses and campus resources. Implications address the need to foster an encouraging and supportive campus and classroom climate and to improve the relationships with LGBTQ resource centers for trans- and queer-spectrum students. PMID:25321425

  4. Operating Efficiency Comes From Teamwork 

    E-print Network

    Relyea, D. L.; Stone, A.

    1997-01-01

    A group of operating and planning personnel formed the INter Plant Utilities Team [INPUT] to improve energy efficiency and reliability for Exxon's Baytown, Texas, refinery and chemical plants complex. The Team coordinates the day-to-day operations...

  5. Psychotropic Medication Use among Children with Autism Spectrum Disorders within the Simons Simplex Collection: Are Core Features of Autism Spectrum Disorder Related?

    ERIC Educational Resources Information Center

    Mire, Sarah S.; Nowell, Kerri P.; Kubiszyn, Thomas; Goin-Kochel, Robin P.

    2014-01-01

    Psychotropic medication use and its relationship to autism spectrum core features were examined in a well-characterized but nonstratified North American sample (N = 1605) of children/adolescents diagnosed with autism spectrum disorders utilizing the "Autism Diagnostic Observation Schedule" and the "Autism Diagnostic…

  6. Antimicrobial Activity and Spectrum Investigation of Eight Broad-Spectrum ?-Lactam Drugs: A 1997 Surveillance Trial in 102 Medical Centers in the United States

    Microsoft Academic Search

    Ronald N Jones; Michael A Pfaller; Gary V Doern; Meridith E Erwin; Richard J Hollis

    1998-01-01

    Because antimicrobial agents become less effective after the emergence of resistance mechanisms in clinically prevalent pathogens, physicians must utilize local, regional, and national antimicrobial susceptibility surveillance data to assist in choices of appropriate agents. An investigation of the spectrum and potency of eight broad-spectrum ?-lactam drugs (cefepime, cefotaxime, ceftazidime, ceftriaxone, imipenem, piperacillin with or without tazobactam, and ticarcillin\\/clavulanic acid) was

  7. Quantum Spectrum Testing

    E-print Network

    Ryan O'Donnell; John Wright

    2015-01-21

    In this work, we study the problem of testing properties of the spectrum of a mixed quantum state. Here one is given $n$ copies of a mixed state $\\rho\\in\\mathbb{C}^{d\\times d}$ and the goal is to distinguish whether $\\rho$'s spectrum satisfies some property $\\mathcal{P}$ or is at least $\\epsilon$-far in $\\ell_1$-distance from satisfying $\\mathcal{P}$. This problem was promoted in the survey of Montanaro and de Wolf under the name of testing unitarily invariant properties of mixed states. It is the natural quantum analogue of the classical problem of testing symmetric properties of probability distributions. Here, the hope is for algorithms with subquadratic copy complexity in the dimension $d$. This is because the "empirical Young diagram (EYD) algorithm" can estimate the spectrum of a mixed state up to $\\epsilon$-accuracy using only $\\widetilde{O}(d^2/\\epsilon^2)$ copies. In this work, we show that given a mixed state $\\rho\\in\\mathbb{C}^{d\\times d}$: (i) $\\Theta(d/\\epsilon^2)$ copies are necessary and sufficient to test whether $\\rho$ is the maximally mixed state, i.e., has spectrum $(\\frac1d, ..., \\frac1d)$; (ii) $\\Theta(r^2/\\epsilon)$ copies are necessary and sufficient to test with one-sided error whether $\\rho$ has rank $r$, i.e., has at most $r$ nonzero eigenvalues; (iii) $\\widetilde{\\Theta}(r^2/\\Delta)$ copies are necessary and sufficient to distinguish whether $\\rho$ is maximally mixed on an $r$-dimensional or an $(r+\\Delta)$-dimensional subspace; and (iv) The EYD algorithm requires $\\Omega(d^2/\\epsilon^2)$ copies to estimate the spectrum of $\\rho$ up to $\\epsilon$-accuracy, nearly matching the known upper bound. In addition, we simplify part of the proof of the upper bound. Our techniques involve the asymptotic representation theory of the symmetric group; in particular Kerov's algebra of polynomial functions on Young diagrams.

  8. Increased Photovoltaic Power Output via Diffractive Spectrum Separation

    E-print Network

    Kim, Ganghun

    In this Letter, we report the preliminary demonstration of a new paradigm for photovoltaic power generation that utilizes a broadband diffractive-optical element (BDOE) to efficiently separate sunlight into laterally spaced ...

  9. A power line data communication interface using spread spectrum technology in home automation

    SciTech Connect

    Shwehdi, M.H.; Khan, A.Z. [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Electrical Engineering] [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Electrical Engineering

    1996-07-01

    Building automation technology is rapidly developing towards more reliable communication systems, devices that control electronic equipments. These equipment if controlled leads to efficient energy management, and savings on the monthly electricity bill. Power Line communication (PLC) has been one of the dreams of the electronics industry for decades, especially for building automation. It is the purpose of this paper to demonstrate communication methods among electronic control devices through an AC power line carrier within the buildings for more efficient energy control. The paper outlines methods of communication over a powerline, namely the X-10 and CE bus. It also introduces the spread spectrum technology as to increase speed to 100--150 times faster than the X-10 system. The powerline carrier has tremendous applications in the field of building automation. The paper presents an attempt to realize a smart house concept, so called, in which all home electronic devices from a coffee maker to a water heater microwave to chaos robots will be utilized by an intelligent network whenever one wishes to do so. The designed system may be applied very profitably to help in energy management for both customer and utility.

  10. Utilization of Resources from NEAs

    NASA Astrophysics Data System (ADS)

    Lewis, J. S.

    2000-01-01

    Materials extracted from Near-Earth Asteroids may find use in future space-based activities as propellants, life-support fluids, or structures. The utility of any space resource is governed by several factors, including energetic accessibility from Low Earth Orbit (LEO), resource concentration, availability of appropriate microgravity extraction and processing techniques, process energy efficiency, process independence of consumables from Earth, and the energetic accessibility of the intended site of use from the asteroid being processed. Additional information is contained in the original extended abstract.

  11. Spread spectrum image steganography.

    PubMed

    Marvel, L M; Boncelet, C R; Retter, C T

    1999-01-01

    In this paper, we present a new method of digital steganography, entitled spread spectrum image steganography (SSIS). Steganography, which means "covered writing" in Greek, is the science of communicating in a hidden manner. Following a discussion of steganographic communication theory and review of existing techniques, the new method, SSIS, is introduced. This system hides and recovers a message of substantial length within digital imagery while maintaining the original image size and dynamic range. The hidden message can be recovered using appropriate keys without any knowledge of the original image. Image restoration, error-control coding, and techniques similar to spread spectrum are described, and the performance of the system is illustrated. A message embedded by this method can be in the form of text, imagery, or any other digital signal. Applications for such a data-hiding scheme include in-band captioning, covert communication, image tamperproofing, authentication, embedded control, and revision tracking. PMID:18267522

  12. The Electromagnetic Spectrum

    NSDL National Science Digital Library

    2012-08-03

    In this lesson, students are introduced to the electromagnetic spectrum. They observe a demonstration of the visible light spectrum created by a flashlight and a prism, complete an activity sheet where they identify the wavelength that is involved in technologies used in their communities, and learn about satellite sensors that remotely sense data. Student worksheets, a data sheet, answer keys, and Web links are included. This is Lesson 3 in Understanding Light, part of IMAGERS, Interactive Media Adventures for Grade School Education using Remote Sensing. The website provides hands-on activities in the classroom supporting the science content in two interactive media books, The Adventures of Echo the Bat and Amelia the Pigeon.

  13. Selling Spectrum Rights

    Microsoft Academic Search

    John McMillan

    1994-01-01

    The design of the FCC spectrum-license auction is a case study in the application of economic theory. Auction theory helped address policy questions such as: Should an open auction or a sealed-bid auction be used? Should the licenses be auctioned sequentially or simultaneously? Should the government allow bids for combinations of licenses, or should it accept only single-license bids? How

  14. Throughput Enhancing Cooperative Spectrum Sensing Strategies for Cognitive Radios

    E-print Network

    Yener, Aylin

    Throughput Enhancing Cooperative Spectrum Sensing Strategies for Cognitive Radios Kyounghwan Lee, whenever not in use, can be captured and used by additional users. To this end, cognitive radios which the opportunistic utilization of white spaces in the UHF/VHF TV band [3]. Cognitive radios allow a secondary

  15. Error Probability of Asynchronous Spread Spectrum Multiple Access Communication Systems

    Microsoft Academic Search

    Kung Yao

    1977-01-01

    Several approaches for the evaluation of upper and lower bounds on error probability of asynchronous spread spectrum multiple access communication systems are presented. These bounds are obtained by utilizing an isomorphism theorem in the theory of moment spaces. From this theorem, we generate closed, compact, and convex bodies, where one of the coordinates represents error probability, while the other coordinate

  16. Spectrum Sharing in Cognitive Radio Systems Under Outage Probablility Constraint 

    E-print Network

    Cai, Pei Li

    2011-02-22

    and bluetooth systems. In most developed countries, the rst model is the predominant choice despite the fact that it is highly ine cient in terms of frequency utilization. In fact, by scanning the spectrum across rural and urban geographical locations, we would...

  17. Implementation Science, Professional Development, and Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Odom, Samuel L.; Cox, Ann W.; Brock, Matthew E.

    2013-01-01

    The increased prevalence of autism spectrum disorders (ASD) has intensified the need for high-quality special education services designed for children and youth with ASD and their families. Implementation science provides guidance for moving innovation, such as utilizing evidence- based practices for students with ASD, into regular practice in…

  18. Efficient, Inexpensive Motors: A New Trend in The Motors Market 

    E-print Network

    Wroblewksi, R. G.

    2001-01-01

    The Consortiun for Energy Efficiency (CEE) has established criteria for premium-efficiency motors above the EPACT standard. CEE has set a uniform efficiency benchmark that all market players (manufacturers, utilities, and end-users) can use. Some...

  19. Chinese Manned Space Utility Project

    NASA Astrophysics Data System (ADS)

    Gu, Y.

    Since 1992 China has been carrying out a conspicuous manned space mission A utility project has been defined and created during the same period The Utility Project of the Chinese Manned Space Mission involves wide science areas such as earth observation life science micro-gravity fluid physics and material science astronomy space environment etc In the earth observation area it is focused on the changes of global environments and relevant exploration technologies A Middle Revolution Image Spectrometer and a Multi-model Micro-wave Remote Sensor have been developed The detectors for cirrostratus distribution solar constant earth emission budget earth-atmosphere ultra-violet spectrum and flux have been manufactured and tested All of above equipment was engaged in orbital experiments on-board the Shenzhou series spacecrafts Space life science biotechnologies and micro-gravity science were much concerned with the project A series of experiments has been made both in ground laboratories and spacecraft capsules The environmental effect in different biological bodies in space protein crystallization electrical cell-fusion animal cells cultural research on separation by using free-low electrophoresis a liquid drop Marangoni migration experiment under micro-gravity as well as a set of crystal growth and metal processing was successfully operated in space The Gamma-ray burst and high-energy emission from solar flares have been explored A set of particle detectors and a mass spectrometer measured

  20. FREQUENCY HOPPING SPREAD SPECTRUM DIRECT SEQUENCE SPREAD SPECTRUM

    E-print Network

    Westall, James M.

    FREQUENCY HOPPING SPREAD SPECTRUM VS. DIRECT SEQUENCE SPREAD SPECTRUM RAYLINK AND RAYTHEON OF THE PRECEEDING MATERIAL. #12;FREQUENCY HOPPING VS. DIRECT SEQUENCE Frequency Hopping vs. Direct Sequence Spread, the techniques specified in the IEEE 802.11 Wireless LAN standard are frequency hopping spread spectrum (FHSS

  1. Spectrum Services 2007

    NASA Astrophysics Data System (ADS)

    Dobos, L.; Budavári, T.; Csabai, I.; Szalay, A. S.

    2008-10-01

    We present the Filter and Spectrum Services consisting of easy-to-use web applications and web services for searching, plotting and managing large collections of spectral energy distribution data and filter profiles as well as for performing various scientific operations on spectra in a unified framework. The services provide keyword search, advanced query forms and SQL query possibilities for selecting spectra or bandpass curves which may be retrieved in a variety of file formats including XML, VOTable and ASCII. All SDSS DR1-DR5 spectra had been loaded into a database as well as the entire 2dF catalog that adds up to more than 2.5 million SEDs of about a million spatial objects, but registered users can upload their own data making it available for the rest of the community and are free to modify or delete them at any time. Theoretical catalogs, such as the Bruzual-Charlot stochastic burst model spectrum library (100k spectra) and the BaSeL stellar library are also available. Scientific services allow building rest-frame composite spectra out of selected spectra; calculating synthetic magnitudes by convolving spectra with an arbitrary set of bandpass curves of optical instrument filters to generate simulated photometric catalogs on-the-fly; galactic extinction correction, fitting of the continuum using different set of templates (Bruzual-Charlot '03 templates, SDSS eigenspectra), line fitting. All scientific functionalities are available from the web user interface and via the SOAP web services for programmers. MySpectrum is a cross-platform version of the spectrum web service for setting up your own spectrum repository. It integrates into the main service allowing easy access to your data for the whole VO community. The main idea behind our web services is to move scientific functionalities physically close to the database in order to spare network bandwidth. This way scientists may do research without setting up expensive hardware, downloading large datasets for days or weeks or installing complicated software.

  2. Analysis of neutron spectrum effects on primary damage in tritium breeding blankets

    NASA Astrophysics Data System (ADS)

    Choi, Yong Hee; Joo, Han Gyu

    2012-07-01

    The effect of neutron spectrum on primary damages in a structural material of a tritium breeding blanket is investigated with a newly established recoil spectrum estimation system. First, a recoil spectrum generation code is developed to obtain the energy spectrum of primary knock-on atoms (PKAs) for a given neutron spectrum utilizing the latest ENDF/B data. Secondly, a method for approximating the high energy tail of the recoil spectrum is introduced to avoid expensive molecular dynamics calculations for high energy PKAs using the concept of recoil energy of the secondary knock-on atoms originated by the INtegration of CAScades (INCAS) model. Thirdly, the modified spectrum is combined with a set of molecular dynamics calculation results to estimate the primary damage parameters such as the number of surviving point defects. Finally, the neutron spectrum is varied by changing the material of the spectral shifter and the result in primary damage parameters is examined.

  3. Miscellaneous Mathematical Utilities

    NSDL National Science Digital Library

    This outstanding collection of online mathematical utilities allows users to perform fairly complex computations based upon calculus, linear algebra, quadratic programming, and trigonometry. Each utility is presented its own Webpage, which includes a brief description of the purpose of the utility and instructions about how to use it. An interesting discussion about computer precision is also provided, explaining how accurately numerical data can be represented on a computer. Two papers on quadratic programming are available for download as well.

  4. Fetal Alcohol Spectrum Disorders (FASDs)

    MedlinePLUS

    ... FASD Cancel Submit Search The CDC Fetal Alcohol Spectrum Disorders (FASDs) Note: Javascript is disabled or is ... Recommend on Facebook Tweet Share Compartir Fetal alcohol spectrum disorders (FASDs) are a group of conditions that ...

  5. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization PRELIMINARY DRAFT ­ NOT EDITED VERSION USES OF CKD OTHER THAN..........................................................................................................................ii CEMENT KILN DUST (CKD.....................................................................................................................2 The Generation of CKD

  6. How utilizes can revitalize industry

    SciTech Connect

    De Vaul, D.; Bartsch, C. [Northeast Midwest Institute, Washington, DC (United States)

    1993-12-31

    During the first weeks of his presidency, Bill Clinton asserted that the nation`s industries must modernize if Americans are to enjoy a rising standard of living. He noted that inadequate knowledge about new production technologies and inadequate capital for plant improvements were making it hard for manufacturers, particularly small and midsized firms, to improve their productivity and economic competitiveness. And though he said his administration would stress the benefits of government research, technology transfer, and financial assistance, President Clinton acknowledged that Washington needs new partners to help modernize U.S. industrial processes. Electric utilities are likely candidates. They have considerable technical expertise and access to large sums of capital that could help industry improve its productivity. Fortuitously, power companies also would benefit by such a partnership stimulating local economic activity and better managing electricity demands. Although many utilities pursue so-called demand-side management programs for their commercial and residential customers, most have not focused much attention on the industrial sector, in part because achieving industrial energy efficiency requires more specialized expertise than do routine energy audits to improve the insulation and lighting of homes and commercial buildings. Yet the reasons to target industry are compelling: Industrial firms consume more than 35 percent of the electricity in the United States, and investment in retooling manufacturing operations with energy-efficient and productive equipment could help spur economic revitalization.

  7. Spectrum Markets with Interference Complementarities

    E-print Network

    Honig, Michael L.

    Spectrum Markets with Interference Complementarities Hang Zhou, Randall A. Berry, Michael L. Honig}@eecs.northwestern.edu, r-vohra@kellogg.northwestern.edu Abstract--Extensive spectrum markets have the potential to enable different agents who may purchase the right to use the same spectrum at nearby locations. Such interference

  8. Hybrid spread spectrum radio system

    DOEpatents

    Smith, Stephen F. (London, TN) [London, TN; Dress, William B. (Camas, WA) [Camas, WA

    2010-02-09

    Systems and methods are described for hybrid spread spectrum radio systems. A method, includes receiving a hybrid spread spectrum signal including: fast frequency hopping demodulating and direct sequence demodulating a direct sequence spread spectrum signal, wherein multiple frequency hops occur within a single data-bit time and each bit is represented by chip transmissions at multiple frequencies.

  9. Efficient conversion of solar energy to biomass and electricity.

    PubMed

    Parlevliet, David; Moheimani, Navid Reza

    2014-01-01

    The Earth receives around 1000 W.m(-2) of power from the Sun and only a fraction of this light energy is able to be converted to biomass (chemical energy) via the process of photosynthesis. Out of all photosynthetic organisms, microalgae, due to their fast growth rates and their ability to grow on non-arable land using saline water, have been identified as potential source of raw material for chemical energy production. Electrical energy can also be produced from this same solar resource via the use of photovoltaic modules. In this work we propose a novel method of combining both of these energy production processes to make full utilisation of the solar spectrum and increase the productivity of light-limited microalgae systems. These two methods of energy production would appear to compete for use of the same energy resource (sunlight) to produce either chemical or electrical energy. However, some groups of microalgae (i.e. Chlorophyta) only require the blue and red portions of the spectrum whereas photovoltaic devices can absorb strongly over the full range of visible light. This suggests that a combination of the two energy production systems would allow for a full utilization of the solar spectrum allowing both the production of chemical and electrical energy from the one facility making efficient use of available land and solar energy. In this work we propose to introduce a filter above the algae culture to modify the spectrum of light received by the algae and redirect parts of the spectrum to generate electricity. The electrical energy generated by this approach can then be directed to running ancillary systems or producing extra illumination for the growth of microalgae. We have modelled an approach whereby the productivity of light-limited microalgae systems can be improved by at least 4% through using an LED array to increase the total amount of illumination on the microalgae culture. PMID:24976951

  10. Spectrum Access Games and Strategic Learning in Cognitive Radio Networks for Delay-Critical Applications

    Microsoft Academic Search

    Mihaela van der Schaar; Fangwen Fu

    2009-01-01

    With the current proliferation of high bandwidth and delay-sensitive multimedia applications and services, each wireless user will try to maximize its utility by acquiring as much spectrum resources as possible unless a preemptive mechanism exists in the network. Thus, emerging solutions for dynamic spectrum access in cognitive radio networks will need to adopt market-based approaches in order to effectively regulate

  11. Optimal Multiband Joint Detection for Spectrum Sensing in Cognitive Radio Networks

    Microsoft Academic Search

    Zhi Quan; Shuguang Cui; Ali H. Sayed; H. Vincent Poor

    2009-01-01

    Spectrum sensing is an essential functionality that enables cognitive radios to detect spectral holes and to opportunistically use under-utilized frequency bands without causing harmful interference to legacy (primary) networks. In this paper, a novel wideband spectrum sensing technique referred to as multiband joint detection is introduced, which jointly detects the primary signals over multiple frequency bands rather than over one

  12. Proposed IEEE802.11 Direct Sequence Spread Spectrum Physical Layer Characteristics

    Microsoft Academic Search

    John Fakatselis

    This paper gives a broad overview of the proposed RF waveforms to be utilized for Wireless LAN's as defined in the proposed IEEE802.11 standard. It provides a brief background of the ISM band and of Spread Spectrum waveforms. Details of the RF specifications for Direct Sequence Spread Spectrum is then described. It addresses implementation specifications as well as international regulatory

  13. Performance Analysis of DS Spread Spectrum System in Multiple Narrowband Interference

    E-print Network

    Vouyioukas, Demosthenes

    -Words: - Spread Spectrum, Direct Sequence (DS), Analog FM, AWGN, Interference, Bit-Error-Rate. 1 Introduction to utilize direct sequence (DS) spreading, using maximal length pseudorandom sequences with long spreadingPerformance Analysis of DS Spread Spectrum System in Multiple Narrowband Interference DEMOSTHENES D

  14. Utilization of Fish Waste

    Microsoft Academic Search

    Raul Perez Galvez; Jean-Pascal Berge

    2013-01-01

    The shortage of marine resources calls for the implementation of new technological processes for providing a better utilization of waste and by-products from fisheries and fish processing activities. Most of these by-products are currently used as raw materials for animal feed. It is estimated that their utilization in human foodstuffs, nutraceuticals, pharmacy, or cosmetics would increase their value fivefold. This

  15. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    1 Center for By-Products Utilization DURABILITY OF CAST-CONCRETE PRODUCTS UTILIZING RECYCLED of Concrete in Barcelona, Spain, June 2000 Department of Civil Engineering and Mechanics College of Engineering and Applied Science THE UNIVERSITY OF WISCONISN-MILWAUKEE #12;1 Durability of Cast-Concrete

  16. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization RECYCLED MATERIALS IN CONCRETE INDUSTRY By Tarun R. Naik-consumer activities along with their possible recycling for the utilization in concrete industry. These by, plastics, glass, recycled concrete pavements for aggregates, recycled asphalt pavement for asphalt

  17. Nonparametric Predictive Utility Inference

    Microsoft Academic Search

    B. Houlding; F. P. A. Coolen

    This work considers the combination of two strands of recent statistical research: that of decision making with uncertain utility and that of nonparametric predictive inference. In doing so we discuss the use of Nonparametric Predictive Utility Inference (NPUI) within a sequential decision selection problem for the situation of a Decision Maker (DM) who is confronted with a choice set that

  18. Utility and Happiness

    Microsoft Academic Search

    Miles Kimball; Robert Willis

    Psychologists have developed effective survey methods of measuring how happy people feel at a given time. The relationship between how happy a person feels and utility is an unresolved question. Existing work in Economics either ignores happiness data or assumes that felt happiness is more or less the same thing as flow utility. The approach we propose in this paper

  19. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization USE OF CLASS F FLY ASH AND CLEAN-COAL ASH BLENDS FOR CAST OF CLASS F FLYASHAND CLEAN-COAL ASHBLENDS FOR CAST CONCRETE PRODUCTS Authors: TarunR.Naik, Director, Center,Illinois Clean Coal Institute RudolphN.Kraus, Research Associate, UWM Center forBy-Products Utilization Shiw S

  20. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    , and chloride-ion penetration as a function #12;-ii- of age. For air entrained concrete mixtures, test specimensCenter for By-Products Utilization DEVELOPMENT OF LOW-COST CONCRETE UTILIZING FOUNDRY INDUSTRY BY TECHNICAL REPORT October 15, 1996, through October 14, 1997 Project Title: DEVELOPMENT OF LOW-COST CONCRETE

  1. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    -Milwaukee, P.O. Box 784, Milwaukee, WI 53201 d Project Manager, Illinois Clean Coal Institute * Director UWM products containing clean coal ash compared to conventional coal ash. Utilization of clean coal ash is much products that utilize clean coal ash. With increasing federal regulations on power plant emissions, finding

  2. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization CLEAN COAL BY-PRODUCTS UTILIZATION IN ROADWAY, EMBANKMENTS-fueled plants, particularly use of eastern coals, has lead to the use of clean coal and using advanced sulfur dioxide control technologies. Figure 1 shows clean coal technology benefits(2) . In 1977, the concept

  3. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    for use of wood ash generated by the forest products industry in concrete (structural-grade concreteCenter for By-Products Utilization DEMONSTRATION OF MANUFACTURING TECHNOLOGY FOR CONCRETE AND CLSM Principal Investigator: Tarun R. Naik UWM Center for By-Products Utilization University of Wisconsin

  4. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    generated by the Wisconsin forest products industry in concrete (structural-grade concrete) and flowableCenter for By-Products Utilization DEMONSTRATION OF MANUFACTURING TECHNOLOGY FOR CONCRETE AND CLSM. Naik UWM Center for By-Products Utilization University of Wisconsin - Milwaukee Other Project Personnel

  5. High efficiency RCCI combustion

    NASA Astrophysics Data System (ADS)

    Splitter, Derek A.

    An experimental investigation of the pragmatic limits of Reactivity Controlled Compression Ignition (RCCI) engine efficiency was performed. The study utilized engine experiments combined with zero-dimensional modeling. Initially, simulations were used to suggest conditions of high engine efficiency with RCCI. Preliminary simulations suggested that high efficiency could be obtained by using a very dilute charge with a high compression ratio. Moreover, the preliminary simulations further suggested that with simultaneous 50% reductions in heat transfer and incomplete combustion, 60% gross thermal efficiency may be achievable with RCCI. Following the initial simulations, experiments to investigate the combustion process, fuel effects, and methods to reduce heat transfer and incomplete combustion reduction were conducted. The results demonstrated that the engine cycle and combustion process are linked, and if high efficiency is to be had, then the combustion event must be tailored to the initial cycle conditions. It was found that reductions to engine heat transfer are a key enabler to increasing engine efficiency. In addition, it was found that the piston oil jet gallery cooling in RCCI may be unnecessary, as it had a negative impact on efficiency. Without piston oil gallery cooling, it was found that RCCI was nearly adiabatic, achieving 95% of the theoretical maximum cycle efficiency (air standard Otto cycle efficiency).

  6. Cosmic Ray Spectrum in Supernova Remnant Shocks

    NASA Astrophysics Data System (ADS)

    Kang, H.

    2011-10-01

    We performed kinetic simulations of diffusive shock acceleration in Type Ia supernova remnants (SNRs) expanding into a uniform interstellar medium (ISM). The preshock gas temperature is the primary parameter that governs the cosmic ray (CR) acceleration, while magnetic field strength and CR injection rate are secondary parameters. SNRs in the hot ISM, with an injection fraction smaller than 10-4, are inefficient accelerators with less than 10 % energy getting converted to CRs. The shock structure is almost test-particle like and the ensuing CR spectrum can be steeper than E-2. Although the particles can be accelerated to the knee energy of 1015.5ZeV with amplified magnetic fields in the precursor, Alfvénic drift of scattering centers softens the source spectrum as steep as E-2.1 and reduces the CR acceleration efficiency.

  7. Power Sales to Electric Utilities

    SciTech Connect

    None

    1989-02-01

    The Public Utilities Regulatory Policies Act (PURPA) of 1979 requires that electrical utilities interconnect with qualifying facilities and purchase electricity at a rate based upon their full avoided costs (i.e., costs of providing both capacity and energy). Qualifying facilities (QF) include solar or geothermal electric units, hydropower, municipal solid waste or biomass-fired power plants, and cogeneration projects that satisfy maximum size, fuel use, ownership, location, and/or efficiency criteria. In Washington State, neither standard power purchase prices based upon a proxy ''avoided plant'', standard contracts, or a standard offer process have been used. Instead, a variety of power purchase contracts have been negotiated by developers of qualifying facilities with investor-owned utilities, public utility districts, and municipally-owned and operated utilities. With a hydro-based system, benefits associated with resource acquisition are determined in large part by how compatible the resource is with a utility's existing generation mix. Power purchase rates are negotiated and vary according to firm energy production, guarantees, ability to schedule maintenance or downtime, rights of refusal, power plant purchase options, project start date and length of contract; front-loading or levelization provisions; and the ability of the project to provide ''demonstrated'' capacity. Legislation was also enacted which allows PURPA to work effectively. Initial laws established ownership rights and provided irrigation districts, PUDs, and municipalities with expanded enabling powers. Financial processes were streamlined and, in some cases, simplified. Finally, laws were passed which are designed to ensure that development proceeds in an environmentally acceptable manner. In retrospect, PURPA has worked well within Washington. In the state of Washington, 20 small-scale hydroelectric projects with a combined generating capacity of 77 MW, 3 solid waste-to-energy facilities with 55 MW of electrical output, 4 cogeneration projects with 34.5 MW of generating capability, and 4 wastewater treatment facility digester gas-to-energy projects with 5 MW of electrical production have come on-line (or are in the final stages of construction) since the passage of PURPA. These numbers represent only a small portion of Washington's untapped and underutilized cogeneration and renewable resource generating potentials. [DJE-2005

  8. On the ionization and ion transmission efficiencies of different ESI-MS interfaces.

    PubMed

    Cox, Jonathan T; Marginean, Ioan; Smith, Richard D; Tang, Keqi

    2015-01-01

    The achievable sensitivity of electrospray ionization mass spectrometry (ESI-MS) is largely determined by the ionization efficiency in the ESI source and ion transmission efficiency through the ESI-MS interface. These performance characteristics are difficult to evaluate and compare across multiple platforms as it is difficult to correlate electrical current measurements to actual analyte ions reaching the detector of a mass spectrometer. We present an effective method to evaluate the overall ion utilization efficiency of an ESI-MS interface by measuring the total gas-phase ion current transmitted through the interface and correlating it to the observed ion abundance measured in the corresponding mass spectrum. Using this method, we systematically studied the ion transmission and ionization efficiencies of different ESI-MS interface configurations, including a single emitter/single inlet capillary, single emitter/multi-inlet capillary, and a subambient pressure ionization with nanoelectrospray (SPIN) MS interface with a single emitter and an emitter array, respectively. Our experimental results indicate that the overall ion utilization efficiency of SPIN-MS interface configurations exceeds that of the inlet capillary-based ESI-MS interface configurations. PMID:25267087

  9. Multi-bandgap high efficiency converter (RAINBOW)

    Microsoft Academic Search

    Carol R. Lewis; Wayne M. Phillips; Virgil B. Shields; Paul M. Stella; Ivan Bekey

    1997-01-01

    Many proposals have been made to increase solar array efficiency by using two or more cells with appropriately spaced bandgaps to span a greater portion of the incident spectrum. One such technique is to split the solar spectrum and focus each portion on a different cell bandgap. Each bandgap is selected to best match the input spectral portion and thus

  10. Information and image integration: project spectrum

    NASA Astrophysics Data System (ADS)

    Blaine, G. James; Jost, R. Gilbert; Martin, Lori; Weiss, David A.; Lehmann, Ron; Fritz, Kevin

    1998-07-01

    The BJC Health System (BJC) and the Washington University School of Medicine (WUSM) formed a technology alliance with industry collaborators to develop and implement an integrated, advanced clinical information system. The industry collaborators include IBM, Kodak, SBC and Motorola. The activity, called Project Spectrum, provides an integrated clinical repository for the multiple hospital facilities of the BJC. The BJC System consists of 12 acute care hospitals serving over one million patients in Missouri and Illinois. An interface engine manages transactions from each of the hospital information systems, lab systems and radiology information systems. Data is normalized to provide a consistent view for the primary care physician. Access to the clinical repository is supported by web-based server/browser technology which delivers patient data to the physician's desktop. An HL7 based messaging system coordinates the acquisition and management of radiological image data and sends image keys to the clinical data repository. Access to the clinical chart browser currently provides radiology reports, laboratory data, vital signs and transcribed medical reports. A chart metaphor provides tabs for the selection of the clinical record for review. Activation of the radiology tab facilitates a standardized view of radiology reports and provides an icon used to initiate retrieval of available radiology images. The selection of the image icon spawns an image browser plug-in and utilizes the image key from the clinical repository to access the image server for the requested image data. The Spectrum system is collecting clinical data from five hospital systems and imaging data from two hospitals. Domain specific radiology imaging systems support the acquisition and primary interpretation of radiology exams. The spectrum clinical workstations are deployed to over 200 sites utilizing local area networks and ISDN connectivity.

  11. Supporting Dynamic Spectrum Access in Heterogeneous LTE+ Networks

    SciTech Connect

    Luiz A. DaSilva; Ryan E. Irwin; Mike Benonis

    2012-08-01

    As early as 2014, mobile network operators’ spectral capac- ity is expected to be overwhelmed by the demand brought on by new devices and applications. With Long Term Evo- lution Advanced (LTE+) networks likely as the future one world 4G standard, network operators may need to deploy a Dynamic Spectrum Access (DSA) overlay in Heterogeneous Networks (HetNets) to extend coverage, increase spectrum efficiency, and increase the capacity of these networks. In this paper, we propose three new management frameworks for DSA in an LTE+ HetNet: Spectrum Accountability Client, Cell Spectrum Management, and Domain Spectrum Man- agement. For these spectrum management frameworks, we define protocol interfaces and operational signaling scenar- ios to support cooperative sensing, spectrum lease manage- ment, and alarm scenarios for rule adjustment. We also quan- tify, through integer programs, the benefits of using DSA in an LTE+ HetNet, that can opportunistically reuse vacant TV and GSM spectrum. Using integer programs, we consider a topology using Geographic Information System data from the Blacksburg, VA metro area to assess the realistic benefits of DSA in an LTE+ HetNet.

  12. The Gas Utility View of Industrial Energy Conservation 

    E-print Network

    Loberg, T. J.

    1980-01-01

    The gas industry fostered more efficient energy utilization long before the idea of energy conservation became fashionable. It became apparent in the late '60's that misguided Federal Legislation was discouraging necessary search for new gas...

  13. Efficient coupling between dielectric waveguide modes and exterior plasmon whispering gallery modes.

    PubMed

    Xu, Chen-Guang; Xiong, Xiao; Zou, Chang-Ling; Ren, Xi-Feng; Guo, Guang-Can

    2013-12-16

    Inefficient coupling between dielectric guided mode and plasmon mode has been overlooked in the past. The coupling mechanism is essentially different from the conventional coupling between dielectric modes. Based on qualitative theoretical analysis, we proposed two methods to strengthen the coupling between dielectric waveguide modes and exterior plasmon whispering gallery modes. One is using a U-shaped bent waveguide to break the adiabatic mode conversion process, and the other is to utilize higher-order dielectric mode to reach phase matching with plasmon mode. Both the transmission spectrum of waveguide and the energy spectrum of cavity demonstrate that the coupling efficiency can be greatly improved. These simple configurations are potential for wide applications, for example, tunable integrated optical devices and sensors. PMID:24514699

  14. A plasma generator utilizing the high intensity ASTROMAG magnets

    NASA Technical Reports Server (NTRS)

    Sullivan, James D.; Post, R. S.; Lane, B. G.; Tarrh, J. M.

    1986-01-01

    The magnet configuration for the proposed particle astrophysics magnet facility (ASTROMAG) on the space station includes a cusp magnetic field with an intensity of a few tesla. With these large magnets (or others) located in the outer ionosphere, many quite interesting and unique plasma physics experiments become possible. First there are studies utilizing the magnet alone to examine the supersonic, sub-Alfvenic interaction with the ambient medium; the scale length for the magnet perturbation is approx. 20 m. The magnetic field geometry when combined with the Earth's and their relative motion will give rise to a host of plasma phenomena: ring nulls, x-points, ion-acoustic and lower-hybrid shocks, electron heating (possible shuttle glow without a surface) launching of Alfvenwaves, etc. Second, active experiments are possible for a controlled study of fundamental plasma phenomena. A controlled variable species plasma can be made by using an RF ion source; use of two soft iron rings placed about the line cusp would give an adequate resonance zone (ECH or ICH) and a confining volume suitable for gas efficiency. The emanating plasma can be used to study free expansion of plasma along and across field lines (polar wind), plasma flows around the space platform, turbulent mixing in the wake region, long wavelength spectrum of convecting modes, plasma-dust interactions, etc.

  15. The splitting spectrum differs from the Taylor spectrum V. Muller*

    E-print Network

    Müller, Vladimír

    and the linear mappings p : p (X, e) p+1 (X, e) are defined by p (xei1 · · · eip ) = n j=1 Ajxej ei1 · · · eip . It is well-known that p+1p = 0 for every p. The Taylor spectrum T (A1, . . . , An) is the setThe splitting spectrum differs from the Taylor spectrum V. M¨uller* Abstract. We construct a pair

  16. Optimal decision strategies for acquisition of spread-spectrum signals in frequency-selective fading channels

    Microsoft Academic Search

    Roland R. Rick; Laurence B. Milstein

    1998-01-01

    The focus of this paper is on the initial acquisition of a direct sequence (DS) spread-spectrum signal utilizing a purely parallel search strategy. A parallel search strategy is utilized because it reduces the acquisition time compared to either serial or partially parallel strategies. In particular, the purpose of this paper is to derive the optimal decision rule, based on the

  17. Autism spectrum disorders

    PubMed Central

    Faras, Hadeel; Al Ateeqi, Nahed; Tidmarsh, Lee

    2010-01-01

    Pervasive developmental disorders are a group of neurodevelopmental disorders characterized by impairments in communication, reciprocal social interaction and restricted repetitive behaviors or interests. The term autism spectrum disorders (ASD) has been used to describe their variable presentation. Although the cause of these disorders is not yet known, studies strongly suggest a genetic basis with a complex mode of inheritance. More research is needed to explore environmental factors that could be contributing to the cause of these disorders. The occurrence of ASD has been increasing worldwide, with the most recent prevalence studies indicating that they are present in 6 per 1000 children. The objectives of this article are to provide physicians with relevant information needed to identify and refer children presenting with symptoms suggestive of ASDs to specialized centers early, and to make them feel comfortable in dealing with public concerns regarding controversial issues about the etiology and management of these disorders. PMID:20622347

  18. Hadronic Spectrum - Multiquark States

    E-print Network

    Stephen L. Olsen

    2009-01-16

    Many newly discovered mesons behave like $\\ccbar$ charmonium states in that they preferentially decay into final states that contain a $c$- and a $\\bar{c}$-quark, but do not fit expectations for any of the unfilled levels of the conventional $\\ccbar$ spectrum. There is a growing suspicion that at least some of these states are {\\it exotic}, {\\it i.e.} have a substructure that is more complex than the quark-antiquark mesons of the classical constituent quark model. Some of these candidate states have a non-zero electric charge and, thus, a minimal quark content of $\\ccbar u\\bar{d}$ or $\\ccbar d\\bar{u}$. In addition, states with similar properties have been observed in the $b$- and $s$-quark sectors. In this report, the experimental situation is briefly reviewed.

  19. Spectrum of magnetohydrodynamic turbulence

    E-print Network

    Stanislav Boldyrev

    2006-02-24

    We propose a phenomenological theory of strong incompressible magnetohydrodynamic turbulence in the presence of a strong large-scale external magnetic field. We argue that in the inertial range of scales, magnetic-field and velocity-field fluctuations tend to align the directions of their polarizations. However, the perfect alignment cannot be reached, it is precluded by the presence of a constant energy flux over scales. As a consequence, the directions of fluid and magnetic-field fluctuations at each scale $\\lambda$ become effectively aligned within the angle $\\phi_{\\lambda}\\propto \\lambda^{1/4}$, which leads to scale-dependent depletion of nonlinear interaction and to the field-perpendicular energy spectrum $E(k_{\\perp})\\propto k_{\\perp}^{-3/2}$. Our results may be universal, i.e., independent of the external magnetic field, since small-scale fluctuations locally experience a strong field produced by large-scale eddies.

  20. Fetal Alcohol Spectrum Disorders

    PubMed Central

    Thomas, Jennifer D.; Warren, Kenneth R.; Hewitt, Brenda G.

    2010-01-01

    Forty years ago, alcohol was not commonly recognized as a teratogen, an agent that can disrupt the development of a fetus. Today, we understand that prenatal alcohol exposure induces a variety of adverse effects on physical, neurological, and behavioral development. Research supported by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) has contributed to the identification of the range and prevalence of fetal alcohol spectrum disorders (FASD), as well as methods for prevention and treatment of FASD. The worldwide prevalence and high personal and societal costs of FASD speak to the importance of this research. This article briefly examines some of the ways that NIAAA has contributed to our understanding of FASD, the challenges that we still face, and how this research is translated into changes in public policy. PMID:23579942

  1. Parent's Guide to Autism Spectrum Disorder

    MedlinePLUS

    ... Home > Health & Education > Publications A Parent’s Guide to Autism Spectrum Disorder What is autism spectrum disorder (ASD)? ... Order a free hardcopy En Español What is autism spectrum disorder (ASD)? Autism spectrum disorder (ASD) is ...

  2. Implementation of GEOSTAR RDSS spread spectrum receiver

    NASA Astrophysics Data System (ADS)

    Motamedi, Masoud; Briskman, Robert D.

    The GEOSTAR Radio Determination Satellite System (RDSS) is designed to provide accurate position information and ancillary two-way message-passing capability to land mobile, marine, and aeronautical users in the US and eventually worldwide. The implementation of an RDSS system is described, and the results of receiver measurements for burst spread-spectrum CDMA (code-division multiple-access) transmissions are presented. The measured results compare very well with the theoretical results and are believed to be the first reported in open literature. The multiple-access technique provides an efficient means to serve a very large number of mobile terminals with accurate position determination and messaging capability.

  3. Clutter depth discrimination using the wavenumber spectrum.

    PubMed

    Benjamin Reeder, D

    2014-01-01

    Clutter depth is a key parameter in mid-frequency active sonar systems to discriminate between sources of clutter and targets of interest. A method is needed to remotely discriminate clutter depth by information contained in the backscattered signal-without a priori knowledge of that depth. Presented here is an efficient approach for clutter depth estimation using the structure in the wavenumber spectrum. Based on numerical simulations for a simple test case in a shallow water waveguide, this technique demonstrates the potential capability to discriminate between a clutter source in the water column vs one on the seabed. PMID:24437850

  4. Japanese telescience technology development for JEM and its utilization.

    PubMed

    Matsumoto, K

    1997-08-01

    Recognizing the importance of the telescience technology for the efficient and improved space environment utilization in JEM, we have undertaken telescience technology development since 1987. The purpose of this paper is to introduce the recent status of our telescience activity, the results of the testbed experiments in these years, and the new activities for the initial JEM operation and its future utilization. PMID:11540773

  5. WHAT'S WRONG WITH ENERGY UTILIZATION IN HYDRAULIC CRANES

    Microsoft Academic Search

    Xingui Liang; Tapio Virvalo

    In this paper a short review on control strategy development of hydraulic crane systems is given. Energy utilization for different alternative driving concepts in an example hydraulic crane is evaluated and compared for a typical duty cycle. The possible factors that result in poor energy utilization and low efficiencies are analyzed and discussed. The answers to the question what is

  6. Broad spectrum bioactive sunscreens.

    PubMed

    Velasco, Maria Valéria Robles; Sarruf, Fernanda Daud; Salgado-Santos, Idalina Maria Nunes; Haroutiounian-Filho, Carlos Alberto; Kaneko, Telma Mary; Baby, André Rolim

    2008-11-01

    The development of sunscreens containing reduced concentration of chemical UV filters, even though, possessing broad spectrum effectiveness with the use of natural raw materials that improve and infer UV absorption is of great interest. Due to the structural similarities between polyphenolic compounds and organic UV filters, they might exert photoprotection activity. The objective of the present research work was to develop bioactive sunscreen delivery systems containing rutin, Passiflora incarnata L. and Plantago lanceolata extracts associated or not with organic and inorganic UV filters. UV transmission of the sunscreen delivery system films was performed by using diffuse transmittance measurements coupling to an integrating sphere. In vitro photoprotection efficacy was evaluated according to the following parameters: estimated sun protection factor (SPF); Boot's Star Rating category; UVA/UVB ratio; and critical wavelength (lambda(c)). Sunscreen delivery systems obtained SPF values ranging from 0.972+/-0.004 to 28.064+/-2.429 and bioactive compounds interacted with the UV filters positive and negatively. This behavior may be attributed to: the composition of the delivery system; the presence of inorganic UV filter and quantitative composition of the organic UV filters; and the phytochemical composition of the P. incarnata L. and P. lanceolata extracts. Among all associations of bioactive compounds and UV filters, we found that the broad spectrum sunscreen was accomplished when 1.68% (w/w) P. incarnata L. dry extract was in the presence of 7.0% (w/w) ethylhexyl methoxycinnamate, 2.0% (w/w) benzophenone-3 and 2.0% (w/w) TiO(2). It was demonstrated that this association generated estimated SPF of 20.072+/-0.906 and it has improved the protective defense against UVA radiation accompanying augmentation of the UVA/UVB ratio from 0.49 to 0.52 and lambda(c) from 364 to 368.6nm. PMID:18662760

  7. Enol Ethers as Substrates for Efficient Z- and Enantioselective Ring-Opening/Cross-Metathesis Reactions Promoted by Stereogenic-at-Mo Complexes. Utility in Chemical Synthesis and Mechanistic Attributes

    PubMed Central

    Yu, Miao; Ibrahem, Ismail; Hasegawa, Masayuki; Schrock, Richard R.; Hoveyda, Amir H.

    2012-01-01

    The first examples of catalytic enantioselective ring-opening/cross-metathesis (EROCM) reactions that involve enol ethers are reported. Specifically, we demonstrate that catalytic EROCM of several oxa- and azabicycles, cyclobutenes and a cyclopropene with an alkyl- or aryl-substituted enol ether proceed readily in the presence of a stereogenic-at-Mo monopyrrolide-monoaryloxide. In some instances, as little as 0.15 mol % of the catalytically active alkylidene is sufficient to promote complete conversion within 10 minutes. The desired products are formed in up to 90% yield and >99:1 enantiomeric ratio (er) with the disubstituted enol ether generated in >90% Z selectivity. The enol ether of the enantiomerically enriched products can be easily differentiated from the terminal alkene through a number of functionalization procedures that lead to the formation of useful intermediates for chemical synthesis (e.g., efficient acid hydrolysis to afford the enantiomerically enriched carboxaldehyde). In certain cases, enantioselectivity is strongly dependent on enol ether concentration: larger equivalents of the cross partner leads to the formation of products of high enantiomeric purity (versus near racemic products with one equivalent). The length of reaction time can be critical to product enantiomeric purity; high enantioselectivity in reactions that proceed to >98% conversion in as brief a reaction time as 30 seconds can be nearly entirely eroded within 30 minutes. Mechanistic rationale that accounts for the above characteristics of the catalytic process is provided. PMID:22272931

  8. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization DEVELOPMENT AND DEMONSTRATION OF HIGH- CARBON CCPs AND FGD BY..................................................................................................................................10 Coal Combustion Products (CCPs.......................................................................................................28 Full-Scale Manufacturing and Technology Transfer Activities

  9. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    Center for By-Products Utilization PRELIMINARY DRAFT REPORT CEMENT KILN DUST (CKD) - BASED SORBENT Science THE UNIVERSITY OF WISCONSIN ­ MILWAUKEE #12;i TABLE OF CONTENTS Cement Kiln Dust (CKD) - Based ;.......................................................................................................... 4 Why Use CKD

  10. By-Products Utilization

    E-print Network

    Wisconsin-Milwaukee, University of

    -Products Utilization E-mail: ymchun@uwm.edu and F. D. Botha Project Manager, Illinois Clean Coal Institute 5776 Coal, University of Wisconsin-Milwaukee, Milwaukee, WI, USA. 4 Project Manager, Illinois Clean Coal Institute

  11. Identifying and managing inappropriate hospital utilization: a policy synthesis.

    PubMed Central

    Payne, S M

    1987-01-01

    Utilization review, the assessment of the appropriateness and efficiency of hospital care through review of the medical record, and utilization management, deliberate action by payers or hospital administrators to influence providers of hospital services to increase the efficiency and effectiveness with which services are provided, are valuable but relatively unfamiliar strategies for containing hospital costs. The purpose of this synthesis is to increase awareness of the scope of and potential for these approaches among health services managers and administrators, third-party payers, policy analysts, and health services researchers. The synthesis will assist the reader to trace the conceptual context and the historical development of utilization review from unstructured methods using individual physicians' professional judgment to structured methods using explicit criteria; to establish the context of utilization review and clarify its uses; to understand the concepts and tools used in assessing the efficiency of hospital use; and to select, design, and evaluate utilization review and utilization management programs. The extent of inappropriate (medical unnecessary) hospital utilization and the factors associated with it are described. Implications for managers, providers, and third-party payers in targeting utilization review and in designing and evaluating utilization management programs are discussed. PMID:3121538

  12. Utility Terrestrial Biodiversity Issues

    PubMed

    BREECE; WARD

    1996-11-01

    / Results from a survey of power utility biologists indicate that terrestrial biodiversity is considered a major issue by only a few utilities; however, a majority believe it may be a future issue. Over half of the respondents indicated that their company is involved in some management for biodiversity, and nearly all feel that it should be a goal for resource management. Only a few utilities are funding biodiversity research, but a majority felt more research was needed. Generally, larger utilities with extensive land holdings had greater opportunities and resources for biodiversity management. Biodiversity will most likely be a concern with transmission rights-of-way construction and maintenance, endangered species issues and general land resource management, including mining reclamation and hydro relicensing commitments. Over half of the companies surveyed have established voluntary partnerships with management groups, and biodiversity is a goal in nearly all the joint projects. Endangered species management and protection, prevention of forest fragmentation, wetland protection, and habitat creation and protection are the most common partnerships involving utility companies. Common management practices and unique approaches are presented, along with details of the survey.KEY WORDS: Biodiversity; Utilities; Rights-of-way; Terrestrial; Management PMID:8895401

  13. The Logical Framework of SPECTRUM

    Microsoft Academic Search

    Radu Grosu; Franz Regensburger

    1994-01-01

    The Spectrum project concentrates on the process of developing well-structured,precise system specifications. Spectrum is a specification language, witha deduction calculus and a development methodology. An informal presentationof the Spectrum language with many examples illustrating its properties isgiven in [BFG+93a, BFG+93b]. The purpose of this article is to describe itsformal semantics.Contents1 Introduction 31.1 Influences from algebra : : : : :

  14. Spectrum transformation for divergent iterations

    NASA Technical Reports Server (NTRS)

    Gupta, Murli M.

    1991-01-01

    Certain spectrum transformation techniques are described that can be used to transform a diverging iteration into a converging one. Two techniques are considered called spectrum scaling and spectrum enveloping and how to obtain the optimum values of the transformation parameters is discussed. Numerical examples are given to show how this technique can be used to transform diverging iterations into converging ones; this technique can also be used to accelerate the convergence of otherwise convergent iterations.

  15. Superfine resolution acoustooptic spectrum analysis

    NASA Technical Reports Server (NTRS)

    Ansari, Homayoon; Lesh, James R.

    1991-01-01

    High resolution spectrum analysis of RF signals is required in applications such as the search for extraterrestrial intelligence, RF interference monitoring, or general purpose decomposition of signals. Sub-Hertz resolution in three-dimensional acoustooptic spectrum analysis is theoretically and experimentally demonstrated. The operation of a two-dimensional acoustooptic spectrum analyzer is extended to include time integration over a sequence of CCD frames.

  16. Superfine resolution acoustooptic spectrum analysis

    NASA Astrophysics Data System (ADS)

    Ansari, Homayoon; Lesh, James R.

    1991-04-01

    High resolution spectrum analysis of RF signals is required in applications such as the search for extraterrestrial intelligence, RF interference monitoring, or general purpose decomposition of signals. Sub-Hertz resolution in three-dimensional acoustooptic spectrum analysis is theoretically and experimentally demonstrated. The operation of a two-dimensional acoustooptic spectrum analyzer is extended to include time integration over a sequence of CCD frames.

  17. Efficient single tobamoviral vector-based bioproduction of broadly neutralizing anti-HIV-1 monoclonal antibody VRC01 in Nicotiana benthamiana plants and utility of VRC01 in combination microbicides.

    PubMed

    Hamorsky, Krystal Teasley; Grooms-Williams, Tiffany W; Husk, Adam S; Bennett, Lauren J; Palmer, Kenneth E; Matoba, Nobuyuki

    2013-05-01

    Broadly neutralizing monoclonal antibodies (bnMAbs) may offer powerful tools for HIV-1 preexposure prophylaxis, such as topical microbicides. However, this option is hampered due to expensive MAb biomanufacturing based on mammalian cell culture. To address this issue, we developed a new production system for bnMAb VRC01 in Nicotiana benthamiana plants using a tobamovirus replicon vector. Unlike conventional two-vector-based expression, this system was designed to overexpress full-length IgG1 from a single polypeptide by means of kex2p-like enzyme recognition sites introduced between the heavy and light chains. An enzyme-linked immunosorbent assay (ELISA) revealed that gp120-binding VRC01 IgG1 was maximally accumulated on 5 to 7 days following vector inoculation, yielding ~150 mg of the bnMAb per kg of fresh leaf material. The plant-made VRC01 (VRC01p) was efficiently purified by protein A affinity followed by hydrophobic-interaction chromatography. ELISA, surface plasmon resonance, and an HIV-1 neutralization assay demonstrated that VRC01p has gp120-binding affinity and HIV-1-neutralization capacity virtually identical to the human-cell-produced counterpart. To advance VRC01p's use in topical microbicides, we analyzed combinations of the bnMAb with other microbicide candidates holding distinct antiviral mechanisms in an HIV-1 neutralization assay. VRC01p exhibited clear synergy with the antiviral lectin griffithsin, the CCR5 antagonist maraviroc, and the reverse transcriptase inhibitor tenofovir in multiple CCR5-tropic HIV-1 strains from clades A, B, and C. In summary, VRC01p is amenable to robust, rapid, and large-scale production and may be developed as an active component in combination microbicides with other anti-HIV agents such as antiviral lectins, CCR5 antagonists, and reverse transcriptase inhibitors. PMID:23403432

  18. Highly efficient blue photoluminescence from colloidal lead-iodide nanoparticles

    NASA Astrophysics Data System (ADS)

    Finlayson, C. E.; Sazio, P. J. A.

    2006-04-01

    We report the synthesis of solvent-stabilized lead-iodide nanoparticles, using a convenient route involving coordinating solvents. The resultant colloids show strong absorption features in the ultraviolet region of the optical spectrum, which are consistent with the formation of semiconducting nanocrystals of lead (II) iodide. An effective-mass approximation model of quantum-confined states is in good agreement with the observed transition energies, giving strong indications of the particle morphologies and dimensions. Intense photoluminescence is also observed, with some spectral tuning possible with ripening time, giving a range of emission photon energies approximately spanning from 2.5 to 3.0 eV. We measure photo-stable luminescence quantum efficiencies of around 20% in solution, increasing to up to 30% if the coordinating ligand is exchanged for a Lewis-base capping layer. This demonstrates the potential for the utilization of lead-iodide nanocrystals in visible optoelectronics applications.

  19. Utilization of extraterrestrial resources: the US case

    SciTech Connect

    Kraniou, D.J.

    1984-01-01

    This is a policy oriented work that examines the possibilities of utilization of extraterrestrial space resources by the United States public and private sectors alike. Specific emphasis is placed on the resources of space located up to the geosynchronous orbit. Resources examined include the space vacuum, the infinitesimally small gravitational forces, the extraterrestrial solar energy, and the geosynchronous orbit. The impact of extraterrestrial resources is analyzed vis-a-vis the United States security, energy, economic, technological, and political (domestic, international) concerns. Scenarios to promote the efficient utilization of these resources are considered, and cost-benefit analyses are developed to examine the degree of justification of these undertakings.

  20. Utility Constrained Energy Minimization In Aloha Networks

    E-print Network

    Khodaian, Amir Mahdi; Talebi, Mohammad S

    2010-01-01

    In this paper we consider the issue of energy efficiency in random access networks and show that optimizing transmission probabilities of nodes can enhance network performance in terms of energy consumption and fairness. First, we propose a heuristic power control method that improves throughput, and then we model the Utility Constrained Energy Minimization (UCEM) problem in which the utility constraint takes into account single and multi node performance. UCEM is modeled as a convex optimization problem and Sequential Quadratic Programming (SQP) is used to find optimal transmission probabilities. Numerical results show that our method can achieve fairness, reduce energy consumption and enhance lifetime of such networks.

  1. Electric Utility Demand-Side Evaluation Methodologies

    E-print Network

    Treadway, N.

    ] is not intended to be the sole criterion used. Neither is it meant to be a substitute for thorough resource planning" (1983, p. 6-1). The current national attention to least-cost planning mirrors this concern for achievement of the most economical electric... of view using a standard benefit-cost methodology. The methodology now in use by several. electric utilities and the Public Utility Commlsslon of Texas includes measures of efficiency and equity. The nonparticipant test as a measure of equity...

  2. Physical Retrieval of Surface Emissivity Spectrum from Hyperspectral Infrared Radiances

    NASA Technical Reports Server (NTRS)

    Li, Jun; Weisz, Elisabeth; Zhou, Daniel K.

    2007-01-01

    Retrieval of temperature, moisture profiles and surface skin temperature from hyperspectral infrared (IR) radiances requires spectral information about the surface emissivity. Using constant or inaccurate surface emissivities typically results in large retrieval errors, particularly over semi-arid or arid areas where the variation in emissivity spectrum is large both spectrally and spatially. In this study, a physically based algorithm has been developed to retrieve a hyperspectral IR emissivity spectrum simultaneously with the temperature and moisture profiles, as well as the surface skin temperature. To make the solution stable and efficient, the hyperspectral emissivity spectrum is represented by eigenvectors, derived from the laboratory measured hyperspectral emissivity database, in the retrieval process. Experience with AIRS (Atmospheric InfraRed Sounder) radiances shows that a simultaneous retrieval of the emissivity spectrum and the sounding improves the surface skin temperature as well as temperature and moisture profiles, particularly in the near surface layer.

  3. Dispersive elements for spectrum splitting in solar cell applications

    Microsoft Academic Search

    A. Bielawny; P.-T. Miclea; A. v. Rhein; R. B. Wehrspohn; S. van Riesen; S. Glunz

    2006-01-01

    Photovoltaic tandem and triple solar cells are currently being developed and produced with reasonable efficiencies at high technological cost. The concept of spectrum splitting has been proposed with the advantage of compatibility to all types of cells. Although additional optical efforts are to be made, external photon management can be achieved to match different solar cell combinations no matter which

  4. Slotted Random Access Spread-Spectrum Networks: An Analytical Framework

    Microsoft Academic Search

    A. Polydoros; J. Silvester

    1987-01-01

    An analytic framework is proposed for the study of singlehop spread-spectrum networks using random access and packet switching under various network topologies and channel conditions. The key feature of the theory is the identification of a set of probabilistic parameters, which, based on a symmetry argument, serve to efficiently summarize the effect on performance of various network considerations such as

  5. The Solar Convection Spectrum

    NASA Technical Reports Server (NTRS)

    Bachmann, Kurt T.

    2000-01-01

    I helped to complete a research project with NASA scientists Dr. David Hathaway (my mentor), Rick Bogart, and John Beck from the SOHO/SOI collaboration. Our published paper in 'Solar Physics' was titled 'The Solar Convection Spectrum' (April 2000). Two of my undergraduate students were named on the paper--Gavrav Khutri and Josh Petitto. Gavrav also wrote a short paper for the National Conference of Undergraduate Research Proceedings in 1998 using a preliminary result. Our main result was that we show no evidence of a scale of convection named 'mesogranulation'. Instead, we see only direct evidence for the well-known scales of convection known as graduation and supergranulation. We are also completing work on vertical versus horizontal flow fluxes at the solar surface. I continue to work on phase relationships of solar activity indicators, but I have not yet written a paper with my students on this topic. Along with my research results, I have developed and augmented undergraduate courses at Birmingham-Southern College by myself and with other faculty. We have included new labs and observations, speakers from NASA and elsewhere, new subject material related to NASA and space science. I have done a great deal of work in outreach, mostly as President and other offices in the Birmingham Astronomical Society. My work includes speaking, attracting speakers, giving workshops, and governing.

  6. The multichannel spectrum analyzer

    NASA Astrophysics Data System (ADS)

    Peterson, A. M.; Chen, K. S.; Linscott, I. R.

    The MCSA is a special-purpose digital signal processor. Its main function is to filter a wide-band signal into many narrower bands, so that each of the output bands has a bandwidth that is a better match to the signal being searched for. The basic MCSA provides simultaneous output bandwidths of approximately 1 Hz, 32 Hz, 1024 Hz, and 74 kHz over a spectrum that is about 8 MHz wide. The input to the MCSA consists of a complex signal sampled at 10 MHz, and the outputs consist of either complex samples or power (square-law-detected) samples. In addition, the MCSA provides an accumulator for taking the integral of the power of the output bands for periods up to 1000 sec. The MCSA hardware is constructed using wire-wrap technology. The implementation of the hardware is done with the aid of a computer program developed specifically for the design of the MCSA. Care has been taken in the MCSA design to ensure that engineering tradeoffs do not adversely affect the performance of the system.

  7. PINS Spectrum Identification Guide

    SciTech Connect

    A.J. Caffrey

    2012-03-01

    The Portable Isotopic Neutron Spectroscopy—PINS, for short—system identifies the chemicals inside munitions and containers without opening them, a decided safety advantage if the fill chemical is a hazardous substance like a chemical warfare agent or an explosive. The PINS Spectrum Identification Guide is intended as a reference for technical professionals responsible for the interpretation of PINS gamma-ray spectra. The guide is divided into two parts. The three chapters that constitute Part I cover the science and technology of PINS. Neutron activation analysis is the focus of Chapter 1. Chapter 2 explores PINS hardware, software, and related operational issues. Gamma-ray spectral analysis basics are introduced in Chapter 3. The six chapters of Part II cover the identification of PINS spectra in detail. Like the PINS decision tree logic, these chapters are organized by chemical element: phosphorus-based chemicals, chlorine-based chemicals, etc. These descriptions of hazardous, toxic, and/or explosive chemicals conclude with a chapter on the identification of the inert chemicals, e.g. sand, used to fill practice munitions.

  8. Fetal Alcohol Spectrum Disorders

    PubMed Central

    Warren, Kenneth R.; Hewitt, Brenda G.; Thomas, Jennifer D.

    2011-01-01

    The adverse effects of prenatal alcohol consumption have long been known; however, a formal description and clinical diagnosis of these effects was not introduced until 1973. Since then, the distinction of the wide range of effects that can be induced by prenatal alcohol exposure, and, consequently, the terminology to describe these effects has continued to evolve. Although much progress has been made in understanding the consequences of prenatal alcohol exposure, challenges still remain in properly identifying all affected individuals as well as their individual patterns of alcohol-induced deficits. Also, as the large numbers of women who continue to drink during pregnancy indicate, prevention efforts still require further refinement to enhance their effectiveness. In addition, the mechanisms underlying alcohol-induced damage have not yet been fully elucidated; as knowledge of the mechanisms underlying alcohol-induced deficits continues to grow, the possibility of minimizing potential harm by intervening during prenatal alcohol exposure is enhanced. Finally, researchers are exploring additional ways to improve or fully restore behavioral and cognitive functions disrupted by prenatal alcohol exposure by treating the individuals with fetal alcohol spectrum disorders, thereby reducing the heavy burden for affected individuals and their families. PMID:23580035

  9. Utility terrestrial biodiversity issues

    NASA Astrophysics Data System (ADS)

    Breece, Gary Allen; Ward, Bobby J.

    1996-11-01

    Results from a survey of power utility biologists indicate that terrestrial biodiversity is considered a major issue by only a few utilities; however, a majority believe it may be a future issue. Over half of the respondents indicated that their company is involved in some management for biodiversity, and nearly all feel that it should be a goal for resource management. Only a few utilities are funding biodiversity research, but a majority felt more research was needed. Generally, larger utilities with extensive land holdings had greater opportunities and resources for biodiversity management. Biodiversity will most likely be a concern with transmission rights-of-way construction and maintenance, endangered species issues and general land resource management, including mining reclamation and hydro relicensing commitments. Over half of the companies surveyed have established voluntary partnerships with management groups, and biodiversity is a goal in nearly all the joint projects. Endangered species management and protection, prevention of forest fragmentation, wetland protection, and habitat creation and protection are the most common partnerships involving utility companies. Common management practices and unique approaches are presented, along with details of the survey.

  10. Utility terrestrial biodiversity issues

    SciTech Connect

    Breece, G.A. [Southern Company, Atlanta, GA (United States); Ward, B.J. [Carolina Power and Light Company, Raleigh, NC (United States)

    1996-11-01

    Results from a survey of power utility biologists indicate that terrestrial biodiversity is considered a major issued by only a few utilities; however, a majority believe it may be a future issue. Over half of the respondents indicated that their company is involved in some management for biodiversity, and nearly all feel that it should be a goal for resource management. Only a few utilities are funding biodiversity research, but a majority felt more research was needed. Generally, larger utilities with extensive land holdings had greater opportunities and resources for biodiversity management. Biodiversity will most likely be a concern with transmission rights-of-way construction and maintenance, endangered species issues and general land resource management, including mining reclamation and hydro relicensing commitments. Over half of the companies surveyed have established voluntary partnerships with management groups, and biodiversity is a goal in nearly all the joint projects. Endangered species management and protection, prevention of forest fragmentation, wetland protection, and habitat creation and protection are the most common partnerships involving utility companies. Common management practices and unique approaches are presented, along with details of the survey. 4 refs.

  11. Utility View of Risk Assessment 

    E-print Network

    Bickham, J.

    1985-01-01

    This paper will address a utility perspective in regard to risk assessment, reliability, and impact on the utility system. Discussions will also include the critical issues for utilities when contracting for energy and capacity from cogenerators...

  12. Design and demonstration of a spectrum-splitting photovoltaic concentrator module

    SciTech Connect

    Borden, P.G.; Gregory, P.E.; Moore, O.E.

    1982-11-01

    A spectrum splitting, concentrating photovoltaic module has been designed and fabricated that uses point focus curved facet Fresnel lenses to concentrate incident sunlight. The concentrated sunlight beam spectrum is split into a high and low energy part by a dichroic filter. The high energy part of the spectrum is transmitted to an AlGaAs solar cell and the low energy part is reflected to a Si cell. Spectrum splitting and using cells that respond best to the two parts of the spectrum splitting and using cells that respond best to the two parts of the spectrum gives a higher efficiency than the use of either cell alone. The experimental module has been tested which consists of 10 AlGaAs and 10 Si cells, and a sunlight to electricity conversion efficiency of 20% has been measured.

  13. Full duplex transmission operation of a 2.45-GHz asynchronous spread spectrum using a SAN convolver.

    PubMed

    Tsubouchi, K; Nakase, H; Namba, A; Masu, K

    1993-01-01

    An asynchronous spread spectrum (SS) modem in the 2.45-GHz band has been implemented using an efficient ZnO-SiO(2)-Si surface acoustic wave (SAW) convolver. The modem, which can operate under full duplex transmission is based on a direct-sequence/code-shift-keying (DS/CSK) method for the modulation. Pseudonoise (PN) codes are chosen from a preferred pair of m-sequences of period 127, and the code rate is 14 MHz. The demodulation is carried out asynchronously, utilizing the coherent correlation characteristics of the SAW convolver. The main interference caused by a transmitted signal in the modem itself is effectively reduced by an RF isolator and the SS process gain. Adequate self-jamming rejection capability has been confirmed; a bit error rate of 10(-6) is observed at -78.3 dB of a desired-to-undesired-signal ratio using an artificial transmission line. PMID:18263209

  14. Innovative Utility Pricing for Industry

    E-print Network

    Ross, J. A.

    INNOVATIVE UTILITY PRICING FOR INDUSTRY James A. Ross Drazen-Brubaker &Associates, Inc. St. Louis, Missouri ABSTRACT The electric utility industry represents only one source of power available to industry. Al though the monopolistic... structure of the electric utility industry may convey a perception that an electric utility is unaffected by competition, this is an erroneous perception with regard to in dustry. Electric utilities face increased compe tition, both from other utilities...

  15. The worldwide leaf economics spectrum

    Microsoft Academic Search

    Ian J. Wright; Peter B. Reich; Mark Westoby; David D. Ackerly; Zdravko Baruch; Frans Bongers; Jeannine Cavender-Bares; Terry Chapin; Johannes H. C. Cornelissen; Matthias Diemer; Jaume Flexas; Eric Garnier; Philip K. Groom; Javier Gulias; Kouki Hikosaka; Byron B. Lamont; Tali Lee; William Lee; Christopher Lusk; Jeremy J. Midgley; Marie-Laure Navas; Ülo Niinemets; Jacek Oleksyn; Noriyuki Osada; Pieter Poot; Lynda Prior; Vladimir I. Pyankov; Catherine Roumet; Sean C. Thomas; Mark G. Tjoelker; Erik J. Veneklaas; Rafael Villar

    2004-01-01

    Bringing together leaf trait data spanning 2,548 species and 175 sites we describe, for the first time at global scale, a universal spectrum of leaf economics consisting of key chemical, structural and physiological properties. The spectrum runs from quick to slow return on investments of nutrients and dry mass in leaves, and operates largely independently of growth form, plant functional

  16. A neural network spectrum analyzer

    Microsoft Academic Search

    James F. Bouchard; Chaoying Zhu; Frank W. Paul

    1995-01-01

    The Fourier Series Neural Network (FSNN) is used as a Neural Network Spectrum Analyzer (NNSA) to gain the advantages of computational parallelism, self-learning intelligence and the capability of modeling complex systems with multiple variables. A comprehensive comparison study between the NNSA and a traditional spectrum analyzer based on the Fast Fourier Transformation (FFT) was conducted to evaluate the performance of

  17. The covariant perturbative string spectrum

    E-print Network

    Davide Forcella; Amihay Hanany; Jan Troost

    2011-03-08

    We provide generating functions for the perturbative massive string spectrum which are covariant with respect to the SO(9) little group, and which contain all the representation theoretic content of the spectrum. Generating functions for perturbative bosonic, Type II, Heterotic and Type I string theories are presented, and generalizations are discussed.

  18. Frequency Allocation; The Radio Spectrum.

    ERIC Educational Resources Information Center

    Federal Communications Commission, Washington, DC.

    The Federal Communications Commission (FCC) assigns segments of the radio spectrum to categories of users, and specific frequencies within each segment to individual users. Since demand for channel space exceeds supply, the process is complex. The radio spectrum can be compared to a long ruler: the portion from 10-540 kiloHertz has been set aside…

  19. Inclusion and the Autism Spectrum

    ERIC Educational Resources Information Center

    Batten, Amanda

    2005-01-01

    Autistic spectrum disorders (ASD) are a lifelong developmental disability that affects the way a person communicates and relates to people around them. People with autistic spectrum disorders experience difficulties with social interaction, social communication and imagination--known as the "triad of impairments". The mainstream school environment…

  20. The ^8B Neutrino Spectrum

    Microsoft Academic Search

    W. T. Winter; S. J. Freedman; J. P. Schiffer; K. E. Rehm

    2004-01-01

    Knowledge of the energy spectrum of ^8B neutrinos is an important ingredient for interpreting experiments that detect energetic neutrinos from the Sun. The neutrino spectrum deviates from the allowed approximation because of the broad alpha-unstable ^8Be final state and recoil order corrections to the beta decay. We have measured the total energy of the alpha particles emitted following the beta