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1

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

Federal Register 2010, 2011, 2012, 2013

...FOUNDATION Promoting Economic Efficiency in Spectrum Use: WSRD SSG Workshop IV AGENCY: The...promote progress toward more efficient spectrum utilization and sharing. SUPPLEMENTARY...accelerate the progress toward more efficient spectrum utilization and sharing. The...

2013-03-26

2

The end of spectrum scarcity [spectrum allocation and utilization  

Microsoft Academic Search

This article discusses the issues of spectrum allocation and the effect of new technologies on spectrum utilization. To understand the impact new radio technologies are having on spectrum availability, it is helpful first to address a common misconception: that spectrum is a concrete and finite resource. Not so. Radio waves do not pass through some ethereal medium called \\

G. Staple; K. Werbach

2004-01-01

3

47 CFR 101.521 - Spectrum utilization.  

Code of Federal Regulations, 2012 CFR

...101.521 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.521 Spectrum utilization. All...

2012-10-01

4

Energy Efficiency and Electric Utilities  

SciTech Connect

The report is an overview of electric energy efficiency programs. It takes a concise look at what states are doing to encourage energy efficiency and how it impacts electric utilities. Energy efficiency programs began to be offered by utilities as a response to the energy crises of the 1970s. These regulatory-driven programs peaked in the early-1990s and then tapered off as deregulation took hold. Today, rising electricity prices, environmental concerns, and national security issues have renewed interest in increasing energy efficiency as an alternative to additional supply. In response, new methods for administering, managing, and delivering energy efficiency programs are being implemented. Topics covered in the report include: Analysis of the benefits of energy efficiency and key methods for achieving energy efficiency; evaluation of the business drivers spurring increased energy efficiency; Discussion of the major barriers to expanding energy efficiency programs; evaluation of the economic impacts of energy efficiency; discussion of the history of electric utility energy efficiency efforts; analysis of the impact of energy efficiency on utility profits and methods for protecting profitability; Discussion of non-utility management of energy efficiency programs; evaluation of major methods to spur energy efficiency - systems benefit charges, resource planning, and resource standards; and, analysis of the alternatives for encouraging customer participation in energy efficiency programs.

NONE

2007-11-15

5

The Efficiency of the FCC Spectrum Auctions  

Microsoft Academic Search

From July 1994 to July 1996, the Federal Communications Commission (FCC) conducted nine spectrum auctions, raising about $20 billion for the U.S. Treasury. The auctions assigned thousands of licenses to hundreds of firms. Were the auctions efficient? Did they award the licenses to the firms best able to turn the spectrum into valuable services for onsumers? There is substantial evidence

Peter Cramton

1998-01-01

6

Energy efficiency and electric utilities  

SciTech Connect

Twenty years have now elapsed since the energy crisis irrevocably changed world energy priorities. The energy crisis banished all apparitions of cheap and almost limitless energy and made the public keenly aware of its scarcity. The sharp rise in energy prices that followed the Arab oil embargo created strong market incentives to conserve energy. Most users have substantially improved the efficiency with which they use energy, although one might lament that the gains have not been larger. In contrast to the increased efficiency with which electricity and other forms of energy are used, electric utilities themselves have singularly failed to improve their heat efficiency in generating electricity. This failure can be attributed to regulation preventing market forces from creating incentive to improve efficiency.

Studness, C.M.

1994-03-15

7

Land mobile spectrum utilization: Detroit, Michigan  

Microsoft Academic Search

The extent of radio frequency utilization by FCC licensees in the Private Land Mobile Radio Services in the Detroit metropolitan area is described. Radio users in these services include among others: police and fire departments, hospitals, public utilities and a variety of private business enterprises. The report analyzes a large amount of monitoring data taken during September 19, 1977-September 28,

L. D. Reed; K. A. Larson; W. V. Tranavitch

1977-01-01

8

Network Model of Decreased Context Utilization in Autism Spectrum Disorder  

ERIC Educational Resources Information Center

Individuals with autism spectrum disorders (ASD) demonstrate impaired utilization of context, which allows for superior performance on the "false memory" task. We report the application of a simplified parallel distributed processing model of context utilization to the false memory task. For individuals without ASD, experiments support a model…

Beversdorf, David Q.; Narayanan, Ananth; Hillier, Ashleigh; Hughes, John D.

2007-01-01

9

Network Model of Decreased Context Utilization in Autism Spectrum Disorder  

Microsoft Academic Search

Individuals with autism spectrum disorders (ASD) demonstrate impaired utilization of context, which allows for superior performance\\u000a on the “false memory” task. We report the application of a simplified parallel distributed processing model of context utilization\\u000a to the false memory task. For individuals without ASD, experiments support a model wherein presentation of one word, e.g.,\\u000a ‘‘apple,’’ strongly activates the neighboring nodes

David Q. Beversdorf; Ananth Narayanan; Ashleigh Hillier; John D. Hughes

2007-01-01

10

Concentrating and spectrum splitting optical device in high efficiency CPV module with five bandgaps  

NASA Astrophysics Data System (ADS)

There is a need for a high efficiency low cost solar energy conversion system. Currently, most concentrating photovoltaic (CPV) systems concentrate the solar spectrum onto triple junction cells to strive for high conversion efficiencies and low cost. Other approaches to high efficiency use spectrum splitting. Triple junction systems are limited in efficiency and spectrum splitting systems are usually too costly for mass production. The objective is to design a spectrum splitting solar concentrator, using reverse ray tracing methods, to overcome the efficiency and cost limitations of current systems by using a single low cost optical device to concentrate and split the solar spectrum onto a large number of target photovoltaic (PV) cells. Dispersive properties of standard optical materials, such as glass or plastic, are utilized to achieve the desired spectral separation. Reverse ray tracing is used to simultaneously optimize the shape of the top and bottom interfaces of the solar concentrator to achieve the desired split spectrum at the target PV cells. Additional strategies to increase system efficiency and minimize optical losses, including draft surface shading and corner rounding losses, are explored. A CPV module, including the spectrum splitting solar concentrator and five PV cells of different bandgaps, is proposed. This spectrum splitting CPV system has a calculated aggregate cell conversion efficiency that exceeds 45%, has the potential to be mass produced, and meets the need for a high efficiency low cost solar energy conversion system.

Taudien, Jerker Y.; Kern, Ludwig A.

2013-09-01

11

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

Microsoft Academic Search

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

T. A. Weiss; F. K. Jondral

2004-01-01

12

Energy efficient new homes programs: Utility experiences  

SciTech Connect

In 1986, the Bonneville Power Administration and many Pacific Northwest utilities embarked on an unparalleled effort to encourage the construction of new homes in the BPA region that go beyond current levels of space heating energy efficiency. By 1995, regional power plans call for 85% of new, electrically space heated homes to be built to these levels, termed the Model Conservation Standards (MCS) by their proposer, the Northwest Power Planning Council. To assist in the development of utility-sponsored new homes programs in the Northwest, a survey was conducted of utilities that have had practical experience in efforts to increase the efficiency of new homes built in their service areas. This paper discusses the results of that survey.

Callaway, J.W.; Branch, K.R.

1987-03-01

13

Energy-Efficient Distributed Spectrum Sensing for Cognitive Sensor Networks  

Microsoft Academic Search

Reliability and energy consumption in detection are key objectives for distributed spectrum sensing in cognitive sensor networks. In conventional distributed sensing approaches, although the detection performance improves with the number of radios, so does the network energy consumption. We consider a combined sleeping and censoring scheme as an energy efficient spectrum sensing technique for cognitive sensor networks. Our objective is

Sina Maleki; Ashish Pandharipande; Geert Leus

2011-01-01

14

Network model of decreased context utilization in autism spectrum disorder.  

PubMed

Individuals with autism spectrum disorders (ASD) demonstrate impaired utilization of context, which allows for superior performance on the "false memory" task. We report the application of a simplified parallel distributed processing model of context utilization to the false memory task. For individuals without ASD, experiments support a model wherein presentation of one word, e.g., ''apple,'' strongly activates the neighboring nodes of closely related words such as ''fruit,'' ''tree,'' whereas in ASD these neighboring nodes are relatively less activated. We demonstrate this model to be consistent with the superior performance on recognition testing on the false memory test, but not on free recall. This may have an anatomic basis in diminished hippocampal neuronal arborization and the abnormal minicolumnar pathology in ASD. PMID:17191098

Beversdorf, David Q; Narayanan, Ananth; Hillier, Ashleigh; Hughes, John D

2007-07-01

15

A spectrum efficient cellular base-station antenna architecture  

Microsoft Academic Search

A concept is considered according to which using the spatial distribution of the users acquired by an array on reception, an antenna system can dynamically assign single narrow beams to illuminate lone mobiles, and broad beams to the numerous groupings along major highways. In this way, the level of cochannel interference is reduced, increasing the spectrum efficiency and, ultimately, the

S. C. Swales; M. A. Beach; J. P. McGeehan

1992-01-01

16

Efficient use of the radio spectrum and bandwidth expansion  

Microsoft Academic Search

Using the definition that the most efficient use of the radio-frequency spectrum is that which produces maximum communication with a point or into and through an area, it is shown that considerable bandwidth expansion is required to achieve optimum communication capacity. The effectiveness of digital modulation in trading bandwidth for interference protection is demonstrated in the environment of a dense

LEROY C. TILLOTSON; CLYDE L. RUTHROFF; VASANT K. PRABHU

1973-01-01

17

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

NASA Astrophysics Data System (ADS)

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.

Petrin, Allen J.

18

A most spectrum-efficient duplexing system: CDD  

NASA Astrophysics Data System (ADS)

The game to play in wireless communications when it comes to increasing spectrum efficiency is to eliminate interference. Currently, all cellular systems use FDD (Frequency Division Duplexing) in an attempt to eliminate the interference from the adjacent cells. Through the use of many technologies only one type of interference remains and that is the adjacent base-tohome mobile interference. TDD (Time Division Duplexing) has not been used for mobile cellular systems, not only because of the adjacent base-to-home mobile interference, but also because of the additional adjacent base-to-home base interference, and adjacent mobile-to-home mobile interference. Therefore, TDD can only be used for small, confined area systems. CDD (Code Division Duplexing) can eliminate all three kinds of interference; the adjacent base-to-home mobile, the adjacent baseto-home base, and the adjacent mobile- to- home in cellular systems. Eliminating each of these interferences makes CDD the most spectrum efficient duplexing system. This talk will elaborate on a set of smart codes, which will make an efficient CDD system a reality.

Lee, William C.

2001-10-01

19

Land mobile spectrum utilization: San Francisco, California and Chicago, Illinois  

NASA Astrophysics Data System (ADS)

Radio frequency utilization by Federal Communication Commission licenses in the San Francisco and Chicago urbanized areas is described. The license include among others: police and fire departments; hospitals; public utilities; marine; and common carrier users. The extent of frequency utilization is described in terms of four occupancy categorizations (zero, low, substantial and very high). The rationale for these categories and their relationship to measured usage data is given. Summary tables enable direct comparison of the use by various individual, radio services, e.g., police, business, taxicab, etc. Separate analyses are given for utilization by each of the land mobile radio services and for each frequency band.

Reed, L. D.

1980-08-01

20

A Spread Spectrum Communications Systems Utilizing an Umbrella Code.  

National Technical Information Service (NTIS)

A pulse stuffing technique is used to eliminate the silent gaps in the transmission of a particular Spread Spectrum system. Unauthorized listeners now have more difficulty in recovering the message content. A two code device was built using both a pseudor...

J. A. Jaques

1975-01-01

21

Imaging of renal transplant: utility and spectrum of diagnostic findings.  

PubMed

Several noninvasive imaging techniques have been developed and improved over recent years that facilitate detection of both vascular and nonvascular postoperative complications as well as diagnosis of diseases related to the transplanted organ itself. In this article, we present a multi-modality review of the spectrum of pathology related to renal transplantation. PMID:21440194

Elsayes, Khaled M; Menias, Christine O; Willatt, Jonathon; Azar, Shadi; Harvin, Howard J; Platt, Joel F

22

Study of Conversion Repeaters in View of the Requirements for Spectrum Efficient Modulation Systems in the Up-Link to Broadcast Satellites, Volume 1.  

National Technical Information Service (NTIS)

As candidate uplink methods, an analog system applying narrowband FM (NBFM) and two DPCM systems differing in method of digitalization, modulation and access, are considered. These systems are evaluated in terms of their spectrum utilization efficiencies ...

1974-01-01

23

Efficiency of food utilization by fruit bats  

Microsoft Academic Search

Neotropical fruit bats consume figs (Ficus spp.) and other fruit in small bites which they suck dry and drop as pellets. The swallowed juice transits the short digestive system in 0.5 h or less. The efficiency of this unusual mode of feeding was determined by comparing the nutritional content of pellets, feces and urine of captive Artibeus jamaicensis to that

Douglas W. Morrison

1980-01-01

24

Analysis of Spectrum Utilization and Message Length Statistics for the Railroad Land Mobile Radio Service.  

National Technical Information Service (NTIS)

In support of the Federal Railroad Administration of the United States Department of Transportation, the Institute for Telecommunication Sciences (ITS) has completed a field spectrum uitilization survey designed to examine individual channel utilization a...

M. Terada

1997-01-01

25

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

Microsoft Academic Search

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

Peter Vandersteegen; Gregor Schwartz; Peter Bienstman; Roel Baets

2008-01-01

26

Photoionization efficiency spectrum and ionization energy of OBrO  

SciTech Connect

The photoionization efficiency (PIE) spectrum of OBrO was measured over the wavelength range {lambda} = 86--126 nm using a discharge flow-photoionization mass spectrometer (DF-PIMS) apparatus coupled to a VUV synchrotron radiation source. Bromine dioxide was generated in a flow tube reactor by first forming BrO via the reaction O({sup 3}P) + Br{sub 2} and then allowing the BrO to react on the cold flow tube wall. The PIE spectrum of the BrO reactant was obtained and the photoionization threshold evaluated from the half-rise point of the step at threshold. This remeasurement yields IE(BrO) = 10.48 {+-} 0.02 eV, which supersedes the previous result. The PIE spectrum of OBrO displayed step-like behavior near threshold. A value of 10.29 {+-} 0.03 eV was obtained for the adiabatic ionization energy (IE) of OBrO from analysis of the photoionization threshold at {lambda} = 120.5 nm. An ab initio determination of the IE of OBrO using the CCSD(T)/6-311+G(3df)//CCD/6-311+G(3df) level of theory gives a value of 10.26 {+-} 0.06 eV, which is in excellent agreement with the experimental result. The results are compared with previous determinations of the IE for both halogen monoxides, XO, and halogen dioxides, OXO (X = Cl, Br, I).

Thorn, R.P. Jr.; Stief, L.J.; Buckley, T.J.; Johnson, R.D. III; Monks, P.S.; Klemm, R.B.

1999-10-21

27

Energy-Efficient Cooperative Spectrum Sensing by Optimal Scheduling in Sensor-Aided Cognitive Radio Networks  

Microsoft Academic Search

A promising technology that tackles the conflict between spectrum scarcity and underutilization is cognitive radio (CR), of which spectrum sensing is one of the most important functionalities. The use of dedicated sensors is an emerging service for spectrum sensing, where multiple sensors perform cooperative spectrum sensing. However, due to the energy constraint of battery-powered sensors, energy efficiency arises as a

Ruilong Deng; Jiming Chen; Chau Yuen; Peng Cheng; Youxian Sun

2012-01-01

28

An analysis of cost efficiency in Swiss multi-utilities  

Microsoft Academic Search

This study presents an empirical analysis of the cost efficiency of a sample of Swiss multi-utilities operating in the distribution of electricity, natural gas and water. The multi-utilities that operate in different sectors are characterized by a strong unobserved heterogeneity. Therefore the measurement of their performance poses an important challenge for the regulators. The purpose of this paper is to

Mehdi Farsi; Massimo Filippini

2009-01-01

29

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

NASA Astrophysics Data System (ADS)

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 fNL 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 fNL 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 fNL 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.

Hazra, Dhiraj Kumar; Sriramkumar, L.; Martin, Jérôme

2013-05-01

30

Spectrum Utilization Study in Support of Dynamic Spectrum Access for Public Safety  

Microsoft Academic Search

Radios for public safety communication have some of the most stringent requirements for access, reliability and robustness. While wireless technology has seen tremendous strides in the past decade, large parts of the public safety infrastructure have unfortunately lagged behind. Today the majority of the Land Mobile Radios (LMR) used by police and fire departments, among others, utilize bandwidth inefficient analog

Roger Bacchus; Tanim Taher; Kenneth Zdunek; Dennis Roberson

2010-01-01

31

Test of relative and absolute price efficiency in regulated utilities  

SciTech Connect

A model for testing all types of relative price inefficiency expands the Averch-Johnson effect and makes it possible to test for absolute price efficiency, which exists if the value of the marginal product for each factor is equated to factor price and implies both cost minimization and production of the optimal quantity of output. Duality theory is used to derive the empirical model using 1973 data for electric utilities. The results indicate that relative and absolute price efficiency were generally not achieved by electric utilities in that year. 36 references, 1 table.

Atkinson, S.E.; Halvorsen, R.

1980-02-01

32

Opportunities and Challenges in Utilizing Millimeter-Wave Spectrum for High Speed Wireless Communications  

Microsoft Academic Search

The 60 GHz band has emerged as an international spectrum opportunity for short-range wireless communication networks. In this paper, technology trends that can impact the commercial deployment of systems utilizing millimeter-wave frequency bands are discussed. Millimeter-wave frequency bands have historically been costly to utilize and traditionally used almost exclusively for government and non-consumer products. Recent and ongoing advances in semiconductor

Rudy Emrick; Steve Franson; John Holmes; Bruce Bosco; Steve Rockwell

2007-01-01

33

Clinical Utility of Autism Spectrum Disorder Scoring Algorithms for the Child Symptom Inventory-4  

ERIC Educational Resources Information Center

|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 =…

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

2008-01-01

34

Quality issues and more efficient utilization of the fish catch  

Microsoft Academic Search

The desire for quality is a motivating force for achieving more efficient utilization of the available harvest. The adoption of methods and techniques that improve the quality status of a higher proportion of the catch ensures better returns. This leads, in turn, to greater recognition of the advantages that can be obtained by using a quality approach and by preventing

H. Allan Bremner

2004-01-01

35

Weak form market efficiency test of oil markets based on generalized spectrum method  

Microsoft Academic Search

Understanding of market efficiency is the cornerstone of market analysis. Oil market efficiency test can not only provide the theoretical foundation for oil price forecast but offer evidence of comparing the information efficiency of different markets. The generalized spectrum method is applied on the daily data from January 2001 to July 2008 to test the weak form efficiency of main

Lv Wen-dong; Pan Hui-feng

2009-01-01

36

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

Federal Register 2010, 2011, 2012, 2013

...licensed networks employing advanced radio devices to meet their spectrum needs...regulatory approaches. 4. Much work is being done to advance dynamic radio technologies, and the Commission believes that this work has already enabled more...

2010-12-28

37

Reclaiming the white spaces: spectrum efficient coexistence with primary users  

Microsoft Academic Search

TV white spaces offer an exciting opportunity for increasing spectrum availability, but white space devices (WSDs) cannot interfere with primary users, including TV channels and wireless microphones (mics). Mics are particularly challenging because their use is dynamic and it is hard to avoid interference since mic receivers are receive-only devices. For this reason the FCC and other regulatory agencies have

George Nychis; Ranveer Chandra; Thomas Moscibroda; Ivan Tashev; Peter Steenkiste

2011-01-01

38

Achieving Energy Efficiency in Buildings that Utilize Subsidized Electrical Energy  

Microsoft Academic Search

This article explores the potential of improving energy efficiency in buildings that utilize subsidized electrical energy. As an example, in Kuwait the government subsidizes 85 percent of the cost of electricity. In addition, the customer pays a fixed figure cost that is 2 fils\\/kWh (0.006 $\\/kWh). This led to an escalation in the demand for electrical energy, until it reached

Fatouh A. Al-Ragom

2004-01-01

39

A combined irradiance-transmittance solar spectrum and its application to photovoltaic efficiency calculations.  

PubMed

SOLTRAN is a flexible computer model for the direct solar beam intensity spectrum at the earth's surface. It has been derived by combining the extra-terrestrial solar spectrum with the atmospheric transmittance spectrum. Application of SOLTRAN to the calculation of the potential efficiency of photovoltaic cells demonstrates the effect of atmospheric absorption bands. These bands prevent unequivocal assignment of optimum energy gap values. PMID:17839483

Ireland, P J; Wagner, S; Kazmerski, L L; Hulstrom, R L

1979-05-11

40

Clinical Utility of Autism Spectrum Disorder Scoring Algorithms for the Child Symptom Inventory4  

Microsoft Academic Search

Few studies examine the clinical utility of autism spectrum disorder (ASD) rating scales for screening referrals to child\\u000a psychiatry clinics. Parents\\/teachers from Long Island, NY, completed the Child Symptom Inventory-4, a DSM-IV-referenced rating\\u000a 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

Kenneth D. Gadow; Joseph Schwartz; Carla DeVincent; Greg Strong; Simone Cuva

2008-01-01

41

Economics and utility energy-efficiency programs: Energy-efficient manufactured housing  

SciTech Connect

As utilities investigate ways to implement conservation programs, the differences between customer and utility economic perspectives become more important. Because utilities bear the cost of new energy sources, energy efficiency investments that are cost-effective to them may not be cost-effective to their customers who pay average energy prices and have different economic parameters. The Bonneville Power Administration (BPA) and other parties in the Pacific Northwest have initiated an innovative manufactured (mobile) home energy conservation program. Because manufactured homes are regulated by the Department of Housing and Urban Development (HUD), are exempt from local regulations, and comprise up to 50% of new housing starts in some parts of the United States, utilities and energy planners need to find creative ways to make the economics of manufactured housing energy-efficiency investments more attractive. Differences between the economic criteria and perspectives of consumers and utilities can be used to design energy-efficiency programs. This paper discusses life-cycle cost (LCC) analysis as a framework for highlighting these differences and examines other economic criteria. It then presents information from the Pacific Northwest manufactured housing program to illustrate the application of this framework to a real-world program. Findings from this program should,be of interest to utility and government planners who are designing innovative energy-efficiency programs.

Lee, A.D.; Onisko, S.A.

1992-10-01

42

Primary-Prioritized Markov Approach for Dynamic Spectrum Access  

Microsoft Academic Search

In order to fully utilize the scarce spectrum resources, with the development of cognitive radio technologies, dynamic spectrum access becomes a promising approach to increase the efficiency of spectrum usage. The spectrum access can be designed in an opportunistic way to efficiently and fairly share the spectrum resources among multiple unlicensed users, while not disturbing primary users' spectrum usage. In

Beibei Wang; Zhu Ji; K. J. Ray Liu

2007-01-01

43

Best Practices Implementation for Hydropower Efficiency and Utilization Improvement  

SciTech Connect

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.

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

2012-01-01

44

Simple technique for measuring Raman gain efficiency spectrum distribution in a single-mode fiber  

NASA Astrophysics Data System (ADS)

Simple technique is proposed for measuring distributed Raman gain efficiency spectrum in a single-mode fiber based on the bidirectional OTDR. The Raman gain efficiency spectra are successfully estimated easily from the relative-index difference and wavelength dependence of the mode field radius (MFR).

Tsutsumi, Yasuhiro; Ohashi, Masaharu

2009-11-01

45

Impact of liquefaction solvent composition on hydrogen utilization efficiency  

SciTech Connect

In previous mechanistic work directed at understanding the modes of bond scission available for relevant coal structures, the authors observed experimentally that the selectivity and efficiency with which donatable hydrogen is used to cleave aryl-alkyl linkages in coal surrogates is highly dependent on the degree of hydrogenation of the donor. The observed variations in efficiency were well reproduced by a mechanistic numerical model incorporating the various competing H-transfer processes. The basic trend elaborated by the model is that an increase in the level of polycyclic aromatic hydrocarbon in the solvent can increase the efficiency of H-utilization markedly at a minor expense in H-transfer rate. Conversely, solvents which are very low in the fully aromatic PCAH component tend to transfer hydrogen faster, but do it less discriminately, such that a much smaller fraction of the hydrogen transferred goes to produce hydrogenolysis, and more goes to simple ring hydrogenation. At that time they proposed that this trend in efficiency could have substantial implications for actual coal liquefaction, but they had no obvious examples at hand to cleanly support this assertion. The recent results of Mochida and coworkers provide a very clear illustration of the relevance of their earlier projections. This demonstration of relevance includes the premise on which these conclusions were based, namely that H-transfer-induced bond scission plays a substantial role in coal liquefaction. In this paper they discuss Mochida's results in light of their earlier findings, and elaborate on the interactive effects of the H-donor and acceptor components of liquefaction solvents.

Malhotra, R.; McMillen, D.F.

1988-01-01

46

Efficiency of sunlight utilization: tubular versus flat photobioreactors  

PubMed

The light saturation effect imposes a serious limitation on the efficiency with which solar energy can be utilized in outdoor algal cultures. One solution proposed to reduce the intensity of incident solar radiation and overcome the light saturation effect is "spatial dilution of light" (i.e., distribution of the impinging photon flux on a greater photosynthetic surface area), but consistent experimental data supporting a significant positive influence of spatial light dilution on the productivity and the photosynthetic efficiency of outdoor algal cultures have never been reported. We used a coiled tubular reactor and compared a near-horizontal straight tubular reactor and a near-horizontal flat panel in outdoor cultivation of the cyanobacterium Arthrospira (Spirulina) platensis under defined operating conditions for optimum productivity. The photosynthetic efficiency achieved in the tubular systems was significantly higher because their curved surface "diluted" the impinging solar radiation and thus reduced the light saturation effect. This interpretation was supported by the results of experiments carried out in the laboratory under continuous artificial illumination using both a flat and a curved chamber reactor. The study also showed that, when the effect of light saturation is eliminated or reduced, productivity and solar irradiance are linearly correlated even at very high diurnal irradiance values, and supported findings that outdoor algal cultures are light-limited even during bright summer days. It was also observed that, besides improving the photosynthetic efficiency of the culture, spatial dilution of light also leads to higher growth rates and lowers the cellular content of accessory pigments; that is, it reduces mutual shading in the culture. The inadequacy of using volumetric productivity as the sole criterion for comparing reactors of different surface-to-volume ratio and of the areal productivity for evaluating the performance of elevated photobioreactors operated outdoors is stressed; it is furthermore suggested that the photosynthetic efficiency achieved by the culture also be calculated to provide a suitable parameter for comparison of different algal cultivation systems operated under similar climatic conditions. Copyright 1998 John Wiley & Sons, Inc. PMID:10099193

Tredici; Zittelli

1998-01-20

47

The efficient discrete Tchebichef transform for spectrum analysis of speech recognition  

NASA Astrophysics Data System (ADS)

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.

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

2013-03-01

48

Energy-efficient dynamic spectrum access using no-regret learning  

Microsoft Academic Search

In this paper, we consider a cross-layer design of dynamic spectrum access in distributive cognitive radio (CR) networks. We model the licensed channel as a finite-state Markov channel (FSMC) and the CR user selects one channel to access and decides transmission rate and power in order to maximize its energy efficiency. We propose a game theoretic framework to formulate this

Yao Lu; Hao He; Jun Wang; Shaoqian Li

2009-01-01

49

A model to study spectrum efficiency of narrow band TDMA cellular radio  

Microsoft Academic Search

Certain radio mobile communication systems have better spectrum efficiency performance than others. If these good systems can be identified then it would be easier to choose the system with the highest capacity. An extensive literature survey has yielded a sparsity of work addressing this issue. The paper aims at developing a model in support of this hypothesis, using simple mathematical

R. C. V. Macario; M. I. S. Dababneh

1992-01-01

50

Outage probability and spectrum efficiency of microcellular mobile radio systems with smart antennas  

Microsoft Academic Search

Relying on the distribution of noncentral multivariate F variates, we investigate the outage probability and spectrum efficiency performance of microcellular and picocellular (indoor) systems with smart antennas. We consider interference limited systems in which the number of interferers exceed or is equal to the number of antenna elements and we present closed-form expressions when the desired signal is subject to

Ming Kang; M.-S. Alouini; Lin Yang

2001-01-01

51

Speed over efficiency: locusts select body temperatures that favour growth rate over efficient nutrient utilization  

PubMed Central

Ectotherms have evolved preferences for particular body temperatures, but the nutritional and life-history consequences of such temperature preferences are not well understood. We measured thermal preferences in Locusta migratoria (migratory locusts) and used a multi-factorial experimental design to investigate relationships between growth/development and macronutrient utilization (conversion of ingesta to body mass) as a function of temperature. A range of macronutrient intake values for insects at 26, 32 and 38°C was achieved by offering individuals high-protein diets, high-carbohydrate diets or a choice between both. Locusts placed in a thermal gradient selected temperatures near 38°C, maximizing rates of weight gain; however, this enhanced growth rate came at the cost of poor protein and carbohydrate utilization. Protein and carbohydrate were equally digested across temperature treatments, but once digested both macronutrients were converted to growth most efficiently at the intermediate temperature (32°C). Body temperature preference thus yielded maximal growth rates at the expense of efficient nutrient utilization.

Miller, Gabriel A.; Clissold, Fiona J.; Mayntz, David; Simpson, Stephen J.

2009-01-01

52

Modeling the efficiency of phosphorus utilization in growing pigs.  

PubMed

Microbial phytase has been used to reduce P excretion from swine to mitigate environmental pollution. The objective of the study was to quantify the effect of feeding a low-P phytase-supplemented diet on growth and P utilization in growing pigs using mathematical models. A total of 20 weaned piglets (BW = 6.5 kg) housed in metabolism cages were randomly assigned to a standard diet (STD) or P-amended diet containing reduced P content and supplemented with phytase (AMN) with 10 pigs/diet. Body weight and feed consumption were recorded weekly so complete growth and cumulative P intake (cPI) curves could be modeled. A function with fixed point of inflexion (Gompertz) and a variable point of inflexion (generalized Michaelis-Menten) were considered in determining bioequivalence by analyzing BW vs. age relationships, whereas the monomolecular function was used to describe BW vs. cPI. All functions were incorporated into a nonlinear mixed effects model, and a first-order autoregressive correlation structure was implemented to take into account repeated measures. There was no difference between the 2 groups in final BW when the Gompertz equation was fitted (176 vs. 178 kg with SE of 7 kg for the STD and AMN, respectively) or the rate parameter (0.0140 vs. 0.0139 with SE of 0.0004 for the STD and AMN, respectively). The generalized Michaelis-Menten equation also showed a similar trend. When BW was expressed as a function of cPI the derivative with respect to cPI represented P efficiency, so it was possible to analyze the expected difference of the 2 diets in using P for BW gain and express it as a continuous function of cPI. The analysis showed through the entire growth period the difference in P efficiency was different from zero. On average, 56 g of supplemented inorganic P was consumed by a pig fed the AMN to reach market weight. In contrast, 309 g of supplemented inorganic P was consumed by the group fed the STD to reach similar BW. It would depend on other factors, but feeding pigs the AMN can result in economic benefit. Pigs fed the AMN excreted 19% less P compared with those fed the STD. In conclusion, nonlinear mixed model analysis (with repeated measures) was suitable for growth and efficiency analysis and showed that pigs fed the AMN consumed less than 20% of the inorganic P and performed as well as those fed the traditional inorganic P supplemented diet. The implications for mitigating P pollution, especially in areas where P loading is already problematic, are substantial. PMID:21531844

Kebreab, E; Strathe, A B; Yitbarek, A; Nyachoti, C M; Dijkstra, J; Lopez, S; France, J

2011-04-29

53

Three biases in cost-efficiency tests of utility energy efficiency programs  

SciTech Connect

Electric utilities in a number of American states devote significant portions of their resources to demand-side management (DSM) programs designed to reduce their customers` electricity consumption. As other jurisdictions consider similar programs, the public policy cost-efficiency criteria for determining how much utilities should pay for DSM remain controversial. This paper develops the appropriate measure of the economic benefits and costs of DSM, using a conventional economic welfare framework, and compares it to the standard cost-effectiveness tests used in most jurisdictions today. The standard tests are found to be incomplete, suffering from three potential biases. Modifications to the standard tests are suggested to address each of the biases. A numerical example is used to illustrate the nature and potential magnitude of the bias in the current tests. 20 refs., 4 figs., 2 tabs.

Braithwait, S.; Caves, D. [Laurits R. Christensen Associates, Inc., Madison, WI (United States)

1994-12-31

54

Protein requirements and ageing: metabolic demand and efficiency of utilization.  

PubMed

The protein requirements of the elderly were investigated with [13C]leucine balance studies of metabolic demand, the efficiency of postprandial protein utilization (PPU) and the consequent apparent protein requirement. Ten elderly subjects aged 68-91 years (five men and five women) and ten young adult subjects aged 21-31 years (five men and five women) were infused with L-[1-13C]leucine for 9 h commencing in the postabsorptive state (0-3 h), continuing during the half-hourly feeding of low-protein meals (LP; protein 3% energy, 3-6 h), and during similar feeding of isoenergetic higher protein meals (HP; protein 15% energy, 6-9 h). Leucine oxidation and balance were determined from plasma [1-13C]-alpha-ketoisocaproate enrichment and expired 13CO2 excretion measured during the 3rd hour of each 3 h period. The protein intake during the HP phase was similar to the habitual intake estimated in the subjects from 24 h urinary N excretion. Metabolic demand was defined as equal to twice the body-protein equivalent of measured postabsorptive leucine oxidation. The efficiency of PPU was calculated from the increased leucine oxidation observed during feeding, and the apparent protein requirement was defined as metabolic demand/PPU and calculated in relation to both body weight (BW) and fat-free mass (FFM) determined by densitometry or bioimpedance. Metabolic demand in the young adults was 0.83 g protein/kg per d; in both elderly groups it was 36% lower when expressed per kg BW and 30% lower when expressed per kg FFM. The apparent protein requirement calculated from metabolic demand and PPU was 0.99 g protein/kg per d in the young adults and this was also lower in the elderly, although this was only significant in the men (0.66 g per kg BW, P = 0.013; 0.79 g per kg FFM, P = 0.02). The results show that in this group of healthy elderly adults protein requirements as assessed from leucine balance studies were either similar to or less than those of younger adults. PMID:9175990

Fereday, A; Gibson, N R; Cox, M; Pacy, P J; Millward, D J

1997-05-01

55

Modeling and Optimization of Efficiency and NOx Emission at a Coal-Fired Utility Boiler  

Microsoft Academic Search

In order to improve boiler efficiency and to reduce the NOx emission of a coal-fired utility boiler using combustion optimization, a hybrid model, by combining support vector regression (SVR) with simplified boiler efficiency model, was proposed to express the relation between operational parameters of the utility boiler and both NOx emission and boiler efficiency. SVR' parameters were determined by the

Huan Zhao; Pei-hong Wang

2009-01-01

56

Utility investments in low-income energy-efficiency programs  

SciTech Connect

In the increasingly competitive utility industry, it is imperative that equity programs be as cost-effective as possible. In some cases, this is accomplished by working in partnership with government programs such as the US Department of Energy`s low-income Weatherization Assistance Program. This paper provides an overview of the DSM and conservation programs being operated by utilities for low-income customers and describes the types of utility-government partnerships that exist.

Brown, M.A.

1995-06-01

57

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

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

58

Highly spectrum efficient OFDM\\/PDM wireless networks by using optical SSB modulation  

Microsoft Academic Search

Optical frequency division multiplexing (OFDM) wireless access network using optical single-sideband modulation is proposed, which allows to deliver different wireless signals from a central station to each base station over an optical fiber network. The optical single-sideband (SSB) OFDM can achieve the highest spectrum efficiency of 0.25 b\\/s\\/Hz. A 0.25 b\\/s\\/Hz has been experimentally verified by the error-free transport of

Ken-Ichi Kitayama

1998-01-01

59

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

ERIC Educational Resources Information Center

|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…

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

2011-01-01

60

Spread spectrum goes commercial  

Microsoft Academic Search

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

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

1990-01-01

61

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

SciTech Connect

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.

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

62

Reviewing the low efficiency of protein utilization in heavy preruminant calves - a reductionist approach  

Microsoft Academic Search

The efficiency of protein utilization for growth in preruminant calves is decreasing with increasing body weight. In contrast to calves weighing less than 100 kg of body weight, heavy preruminant calves do not respond in protein retention to an increased intake of indispensable amino acids in dose-response studies. The marginal efficiency of protein utilization is low compared with pigs and

Borne van den J. J. G. C; Johannes M. A. J. Verdonk; Johan W. Schrama; Walter J. J. Gerrits

2006-01-01

63

Diffractive optical elements utilized for efficiency enhancement of photovoltaic modules.  

PubMed

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

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

2011-06-01

64

Federal Energy Efficiency through Utility Partnerships: Federal Energy Management Program (FEMP) Program Overview Fact Sheet  

SciTech Connect

This Utility Program Overview describes how the Federal Energy Management Program (FEMP) utility program assists Federal energy managers. The document identifies both a utility financing mechanism and FEMP technical assistance available to support agencies' implementation of energy and water efficiency methods and renewable energy projects.

Beattie, D.; Wolfson, M.

2001-07-30

65

Energy utilization and efficiency analysis for hydrogen fuel cell vehicles  

Microsoft Academic Search

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,

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

2006-01-01

66

Efficient use of energy by utilizing gas turbine combined systems  

Microsoft Academic Search

The gas turbine engine is characterized by its relatively low capital cost compared with steam power plants. It has environmental advantages and short construction lead time. However, conventional industrial engines have lower efficiencies especially at part load. One of the technologies adopted nowadays for improvement is the “combined cycle”. Hence, it is expected that the combined cycle continues to gain

Yousef S. H Najjar

2001-01-01

67

Selection for efficiency of feed utilization in growing mice  

Microsoft Academic Search

Selection was practised for improved feed efficiency (gain\\/feed intake) of mice on two alternative feeding regimes. In one set of lines animals were fed ad libitum, in the other set they were individually fed a fixed amount of feed (about 10% below the control ad libitum intake) which was not changed over generations. For each treatment, a pair of replicate

E. Ytiksel; W. G. Hill; R. C. Roberts

1981-01-01

68

Spectrum splitting photovoltaics: light trapping filtered concentrator for ultrahigh photovoltaic efficiency  

NASA Astrophysics Data System (ADS)

While monolithic multijunction solar cell approaches have been quite successful, current and lattice matching requirements limit the maximum possible achievable efficiencies. Spectrum splitting, where light is optically distributed among subcells with differing bandgaps, avoids these constraints and offers a route to achieving higher efficiencies (<50%). We investigate a spectrum splitting approach where concentrated sunlight is trapped in a textured dielectric slab and then selectively coupled into underlying solar cells of different bandgaps through omnidirectional filters. We develop a multipass optical model to find regimes of high optical efficiency based on parameters such as slab refractive index, number of subcells, and angle restriction of light escape from the slab. Based on these results and filter design considerations, we describe a specific design featuring a textured slab of SiO2 coated with angle restricting incoupling elements based on compound parabolic concentrators and three underlying multijunction junction solar cells, for a total of eight junctions with bandgaps ranging from 2.2eV to 0.7. Using the multipass model in conjunction with modified detailed balance calculations, we find module efficiencies exceeding 50% are possible with an acceptance angle restricted to 20° or less and concentrations of a few hundred suns with ideal omnidirectional filters. Finally as proof of concept, we design a full set of omnidirectional filters for this design. Based on alternating layers of TiO2 and SiO2, we achieve angle averaged reflectivity greater than 90% within the reflection band and angle averaged transmission of approximately 90% within the transmission band for the long pass filter, for nearly 48% receiver efficiency.

Kosten, Emily D.; Warmann, Emily C.; Lloyd, John; Atwater, Harry A.

2013-09-01

69

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

PubMed Central

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.

Sabri, Suriana; Nielsen, Lars K.

2013-01-01

70

Polyhedral specular reflector design for ultra high spectrum splitting solar module efficiencies (>50%)  

NASA Astrophysics Data System (ADS)

One pathway to achieving ultra-high solar efficiencies (<50%) is employing a spectrum splitting optical element with at least 6 subcells and significant concentration (100-500 suns). We propose a design to meet these criteria, employing specular reflection to split and divide the light onto appropriate subcells. The polyhedral specular reflector incorporates a high index parallelepiped with seven subcells. The subcells are placed around the parallelepiped such that light entering at normal incidence encounters the subcells in order from highest to lowest bandgap, with the ray path reflecting at a 90° angle until the light is fully absorbed. Previous studies of the design have shown that concentration and filters are necessary to achieve high efficiencies and thus the current iteration of the design employs shortpass filters and two stages of concentration. Ray tracing of the current iteration shows exceeding 50% efficiency is possible for current subcell qualities with perfect shortpass filters while 50% module efficiencies are only possible for very high quality (<6% ERE) subcells with commercially available shortpass filters. However, even with commercially available filters and achievable subcell quality, ray tracing results show very high (<43%) module efficiency.

Eisler, Carissa N.; Kosten, Emily D.; Warmann, Emily C.; Atwater, Harry A.

2013-09-01

71

Efficient synthesis of nucleoside aryloxy phosphoramidate prodrugs utilizing benzyloxycarbonyl protection  

PubMed Central

An efficient method for the synthesis of nucleoside phosphoramidates prodrugs (6a–f) has been developed that employs a simple protection/deprotection sequence of the nucleoside with benzyloxycarbonyl (Cbz). The coupling reaction of Cbz-protected derivatives (5a–f) with phenyl-(ethoxy-L-alaninyl)-phosphorochloridate (7), followed by Cbz group removal by hydrogenolysis provided the phenyl phosphoramidate ProTides (6a–f) in excellent overall yields.

Cho, Jong Hyun; Amblard, Franck; Coats, Steven J.; Schinazi, Raymond F.

2011-01-01

72

Universal and efficient compressed sensing by spread spectrum and application to realistic Fourier imaging techniques  

NASA Astrophysics Data System (ADS)

We advocate a compressed sensing strategy that consists of multiplying the signal of interest by a wide bandwidth modulation before projection onto randomly selected vectors of an orthonormal basis. First, in a digital setting with random modulation, considering a whole class of sensing bases including the Fourier basis, we prove that the technique is universal in the sense that the required number of measurements for accurate recovery is optimal and independent of the sparsity basis. This universality stems from a drastic decrease of coherence between the sparsity and the sensing bases, which for a Fourier sensing basis relates to a spread of the original signal spectrum by the modulation (hence the name "spread spectrum"). The approach is also efficient as sensing matrices with fast matrix multiplication algorithms can be used, in particular in the case of Fourier measurements. Second, these results are confirmed by a numerical analysis of the phase transition of the ?1-minimization problem. Finally, we show that the spread spectrum technique remains effective in an analog setting with chirp modulation for application to realistic Fourier imaging. We illustrate these findings in the context of radio interferometry and magnetic resonance imaging.

Puy, Gilles; Vandergheynst, Pierre; Gribonval, Rémi; Wiaux, Yves

2012-12-01

73

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

SciTech Connect

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).

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

2009-03-04

74

Theoretical investigation of the spectrum and conversion efficiency of short wavelength extreme-ultraviolet light sources based on terbium plasmas  

SciTech Connect

The emission spectrum and conversion efficiency of laser-produced terbium plasmas are theoretically investigated on the basis of computational atomic data. The theoretically calculated spectrum reproduces the main peak of observed spectrum at {lambda}=6.5 nm, which originates from 4d-4f transitions of near palladiumlike ions (Tb{sup 19+}). A simple model of the isothermal expansion of terbium plasma suggests that efficient emission can be achieved by pumping the plasma with a laser pulse at an intensity of approximately one order of magnitude greater than that used with tin sources at {lambda}=13.5 nm.

Sasaki, Akira [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 8-1 Umemidai, Kizugawa-shi, Kyoto 619-0215 (Japan); Nishihara, Katsunobu [Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Sunahara, Atsushi; Furukawa, Hiroyuki [Institute for Laser Technology, 1-8-4 Utsubohonmachi, Nishi-ku, Osaka 550-0004 (Japan); Nishikawa, Takeshi [Department of Electrical and Electronic Engineering, Okayama University, 1-1 Naka 3-Chome, Tsushima, Okayama 700-8530 (Japan); Koike, Fumihiro [Physics Laboratory, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan)

2010-12-06

75

Area spectrum efficiency of TV White Space wireless system with transmit power control  

Microsoft Academic Search

As a technical approach to solve spectrum scarcity problem, cognitive radio (CR), which enables more flexible use of spectrum through spectrum sharing technology, draws huge attention recently. TV White Space which means geographically unused spectrum in TV broadcasting band is considered as a good frequency band candidate for CR based spectrum sharing technology due to some reasons. However, primary user

Sang Yun Lee; Sung Hee An; Yang Moon Yoon

2010-01-01

76

Efficient spin filter utilizing antidot potential in semiconductor heterostructures  

NASA Astrophysics Data System (ADS)

We propose a highly efficient spin filter using artificial potential created by an antidot gate-electrode, STM tip, etc., in semiconductor heterostructures in the presence of spin-orbit interaction. The strength of such a potential is electrically tunable and it can be attractive as well as repulsive. In our previous paper,footnotetextM. Eto and T. Yokoyama, J. Phys. Soc. Jpn. 78, 073710 (2009). we formulated the spin Hall effect due to the scattering by the potential in terms of phase shifts and showed that it is extremely enhanced by the resonant scattering when an attractive potential is properly tuned. In the present study, we examine three- and four-terminal devices including an artificial potential as a spin filter. We numerically evaluate the spin polarization of the output current when an unpolarized current is injected from a terminal. With an axially symmetric potential, we observe the spin polarization of more than 50%.footnotetextT. Yokoyama and M. Eto, Phys. Rev. B 80, 125311 (2009). Although the polarization is smaller when the axial symmetry is broken, we find that realistic devices could work well as an efficient spin filter.footnotetextT. Yokoyama and M. Eto, Physica E, in press.

Yokoyama, Tomohiro; Eto, Mikio

2010-03-01

77

On-board vehicular network method for efficient generator utilization  

SciTech Connect

To utilize the full power capacity of alternators the alternator phases are connected through a transformer to the rectifier which provides rectified output to a battery. The transformer has tapped windings, the taps being placed in circuit with the alternator-rectifier network in dependence on a speed control signal, for example derived from the frequency of the alternator, to effect tap changing and matching of the internal impedance of the alternator to the battery/load combination. In accordance with one feature, the taps are on the primary, and a-c switches such as triacs are selectively energized as the speed of the generator changes; in accordance with another embodiment, the taps are on the secondary of the transformer, and unilaterally conductive switches, such as thyristors or SCRs, can be used, in parallel with the rectifier diodes of the rectifying array, and selectively fired as a function of speed. A nominal output alternator thus can provide secondary output currents. The closeness of matching and eventual output power depending on the voltage rating of the alternator and the number of taps on the transformer, and hence the degree of match obtainable.

Gretsch, R.

1983-12-06

78

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

National Technical Information Service (NTIS)

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. Howev...

C. Golldman G. Edgar J. Schlegel M. Chait P. Cappers W. Shirley

2009-01-01

79

Electric-utility energy-efficiency and load-management programs: Resources for the 1990s  

Microsoft Academic Search

The primary purpose of this report is to suggest much larger and more active roles for utilities in acquiring energy-efficiency and load-management resources. Valuable utility actions include increased efforts to: Assess existing and new demand-side technologies; Test alternative ways to implement demand-side programs; Aggressively acquire energy and capacity resources through efficiency and load- management programs; Work with governments to support

1989-01-01

80

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

SciTech Connect

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.

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

2011-02-25

81

Efficient Utilization of Employees in the Garment Industry Using Operations Research  

Microsoft Academic Search

Performance of employees in an organization determines the level of its success. Due to this reason efficient utilization of the employees in the operations matters a lot. The aim of this study is to develop a mechanism for the manufacturers of garment to utilize its workforce at an optimal level. The manufacture of garment is mainly based on the production

W. K. I. Fernando; D. J. C. Suriyaarachchi

2008-01-01

82

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...

83

Managed Care Patients With Heart Failure: Spectrum of Ventricular Dysfunction and Predictors of Medication Utilization  

Microsoft Academic Search

BackgroundHeart failure (HF) is a common clinical syndrome resulting in high morbidity and mortality. We examined the spectrum of ventricular dysfunction, and investigated the predictors of angiotensin-converting enzyme (ACE) inhibitor, ?-blocker, and spironolactone prescription in 1613 managed care patients with HF.

Carla A. Sueta; Alain G. Bertoni; Mark W Massing; Jill Mcardle; Vanessa Duren-Winfield; Jennifer Davis; Janet B. Croft; David C. Goff

2005-01-01

84

Increasing the Efficiency of a Piezoelectric Aluminum Nitride Microstrip Resonator by Utilizing High Temperature Superconductors  

Microsoft Academic Search

High temperature superconductors have potential applications in the field of microwave devices and circuits. To utilize these materials in such a way as to increase the efficiency of these microwave devices would be beneficial for high efficiency\\/low noise applications. This dissertation accomplishes the following goals: (1) The design and fabrication of an initial device that increases the quality factor, Q,

Edward David Goff

1995-01-01

85

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...

86

Efficiency of Feed Utilization in Swine: A Review of Research and Current Applications.  

National Technical Information Service (NTIS)

A review of research on the efficiency of feed utilization in swine during the growing-finishing period is presented. The major conclusions include the following: Efficiency (E), expressed either as units of feed consumed (F) per unit of gain in weight (G...

B. Bereskin N. C. Steel

1986-01-01

87

Acquisition or utilization, which is more critical for enhancing phosphorus efficiency in modern crops?  

Microsoft Academic Search

Phosphorus (P) is one of the major factors worldwide limiting crop growth. Enhancing P efficiency in plants can be achieved through improving P acquisition, utilization, or both. Which of these approaches is more critical for enhancing P efficiency in crops, particularly in intensive cropping systems? P availability is unevenly distributed through the soil profile. Most modern crop cultivars are selected

Xiurong Wang; Jianbo Shen; Hong Liao

2010-01-01

88

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

Microsoft Academic Search

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

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

2010-01-01

89

A Comparison of Health Care Utilization and Costs of Children With and Without Autism Spectrum Disorders in a Large Group-Model Health Plan  

Microsoft Academic Search

OBJECTIVE.Data on the current costs of medical services for children with autism spectrum disorders are lacking. Our purpose for this study was to compare health care utilization and costs of children with and without autism spectrum disorders in the same health plan. PATIENTS AND METHODS.Participants included all 2- to 18-year-old children with autism spectrum disorders (n 3053) and a random

Lisa A. Croen; Daniel V. Najjar; G. Thomas Ray; Linda Lotspeich; Pilar Bernal

2010-01-01

90

A Comparison of Health Care Utilization and Costs of Children with and without Autism Spectrum Disorders in a Large Group-Model Health Plan  

ERIC Educational Resources Information Center

|Objective: Data on the current costs of medical services for children with autism spectrum disorders are lacking. Our purpose for this study was to compare health care utilization and costs of children with and without autism spectrum disorders in the same health plan. Patients and Methods: Participants included all 2- to 18-year-old children…

Croen, Lisa A.; Najjar, Daniel V.; Ray, G. Thomas; Lotspeich, Linda; Bernal, Pilar

2007-01-01

91

Efficient pricing of private power supply under the Public Utilities Regulatory Policies Act  

SciTech Connect

The Public Utilities Regulatory Policies Act of 1978 (PURPA) began a new era in electric utility regulation by creating a new class of power producers that operate free from traditional cost-of-service regulation but sell their power to conventionally regulated public utilities. The Act specified that the utility should pay an administratively-determined avoided-cost price equal to all costs it saved by purchasing private power. The author discusses the efficiency implications of avoided-cost pricing, considers a methodology for determining efficient avoided-cost prices and examines actual prices at which power was transacted to assess, ex post, their efficiency. The findings identify variables that influence the magnitude of an efficient avoided-cost payment, including the load level prevailing when the power is supplied, the commitment level of the supplier's contract with the utility and the utility's level of capacity saturation. Some states appear to make payments outside the efficient price parameters even after adjusting for variables not included in the parameters. In 1988, the Federal Energy Regulatory Commission issued a ruling which encouraged states to use bidding to select and price private power supply contracts. Some of the strategic issues are examined that arise in this new regime. The model developed suggests that bidders will find it profitable to raise their bids above those they would place in a static auction when they instead participate in a dynamic auction characterized by repeated rounds of bidding in which bidders drop out of the bidding after winning a contract. While this bid inflation reduces some of the distributive properties anticipated with competitive bidding, the model does demonstrate that contracts for private power supply are awarded efficiently under competitive bidding, whereas there is no guarantee of efficiency under the first-come, first-served rule applied under avoided-cost pricing.

Bittenbender, S.L.

1992-01-01

92

Opportunistic Spectrum Sharing in Cognitive MIMO Wireless Networks  

Microsoft Academic Search

Cognitive radio has been recently proposed as a promising technology to improve the spectrum utilization. In this paper, we consider the spectrum sharing between a large number of cognitive radio users and a licensed user in order to enhance the spectrum efficiency. With the deployment of M antennas at the cognitive base station, an opportunistic spectrum sharing approach is proposed

Karama Hamdi; Wei Zhang; Khaled Ben Letaief

2009-01-01

93

Asymptotic optimality for distributed spectrum sharing using bargaining solutions  

Microsoft Academic Search

Recent studies on spectrum usage reveal poor utilization, both spatially and temporally. Opportunistic use of licensed spectrum while limiting interference to primary users can enhance spectrum reuse and provide orders of magnitude improvement in available channel capacity. This calls for spectrum sharing protocols that are dynamic, flexible, and efficient, in addition to being fair to end users. We employ cooperative

Juan E. Suris; Luiz A. DaSilva; Zhu Han; Allen B. MacKenzie; Ramakant S. Komali

2009-01-01

94

Energy-efficient new homes programs: An analysis of utility experience  

SciTech Connect

This paper describes the results of a survey of thirty utilities outside the Pacific Northwest that have had practical experience in efforts to increase the efficiency of new homes built in their service areas. The experience of these utilities is examined from the standpoint of why they adopted new energy efficienct homes programs; how they structured and have implemented their programs; and what factors appear to be involved in achieving success for their efforts.

Callaway, J.W.; Branch, K.W.; Davis, L.J.

1987-02-01

95

On the Achievable Efficiency-Fairness Tradeoff in Utility-Optimal MAC Protocols  

NASA Astrophysics Data System (ADS)

We use the network utility maximization (NUM) framework to create an efficient and fair medium access control (MAC) protocol for wireless networks. By adjusting the parameters in the utility objective functions of NUM problems, we control the tradeoff between efficiency and fairness of radio resource allocation through a rigorous and systematic design. In this paper, we propose a scheduling-based MAC protocol. Since it provides an upper-bound on the achievable performance, it establishes the optimality benchmarks for comparison with other algorithms in related work.

Lee, Jang-Won; Chiang, Mung; Calderbank, A. Robert

96

PRIVATIZED PUBLIC UTILITY PRICING, EFFICIENCY, AND THE IMPLICATIONS OF SUBSIDIES AND UNCERTAINTY  

Microsoft Academic Search

Abstract Criticism is frequently levelled at privatized public utilities for not appearing to pass on to consumers,the gains from increased production efficiency that were held out as the basis for selling public assets. This criticism simultaneously accepts that the efficiency gains do occur and that the new private monopoly,is greedily retaining excessive profits. The benchmark,models,constructed show that the prices charged

Ronald D. Ripple

97

Efficient Discovery of Spectrum Opportunities with MAC-Layer Sensing in Cognitive Radio Networks  

Microsoft Academic Search

Sensing\\/monitoring of spectrum-availability has been identified as a key requirement for dynamic spectrum allocation in cognitive radio networks (CRNs). An important issue associated with MAC-layer sensing in CRNs is how often to sense the availability of licensed channels and in which order to sense those channels. To resolve this issue, we address (1) how to maximize the discovery of spectrum

Hyoil Kim; Kang G. Shin

2008-01-01

98

A bright idea for industry. [demand side management: utilization of energy-efficiency technology  

SciTech Connect

Tucked in the middle of the National Energy Policy Act is a little-noticed program with a big mission: to tap the huge pool of energy-efficiency potential in the industrial sector, and in the process spur industrial competitiveness. The new legislation focuses on one particularly promising strategy: forging a partnership between utilities and their industrial customers. This partnership expands on the concept of utilities helping local companies find and use the latest technologies in order to enhance efficiency and productivity. Building on existing state economic development and energy initiatives, utilities can provide assessments and financing to help industries improve their production process. Utility-business-state economic development partnerships offer benefits to several parties. Working with utilities will give industry an opportunity to define a long-term strategy that links energy efficiency and business competiveness. This type of partnership will enable firms to lower their operating costs and shift capital savings to other uses. Such partnerships also provide economic development agencies and officials with new tools for packaging and promoting economic development projects. They can be valuable as business expansion or retention incentives and as spurs to industrial modernization. Moreover, the program might be linked to existing technology transfer efforts, helping finance facilities needed to commercialize new products or modernize manufacturing processess. As a result, new investment would be stimulated, jobs saved or created, and industrial competitiveness enhanced.

Bartsch, C.; DeVaul, D.

1993-05-01

99

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

SciTech Connect

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.

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

1997-06-01

100

Analyzing the Energy Utilization Efficiency of Renewable Energy Resources. Part 2: Exergy Analysis Method  

Microsoft Academic Search

Exergy analysis is a powerful tool in the design, simulation and performance evaluation of thermal and thermo chemical systems. A particular thermo dynamical system is the society of a country or a region. This method of exergy analysis has recently been used with an increasing interest to assess the energy utilization efficiencies of countries. Part 2 of the present study,

Arif Hepbasli; Zafer Utlu

2006-01-01

101

Effects of human element on efficiency of food utility in mice  

Microsoft Academic Search

To investigate the effects of human element on efficiency of food utility (EFU) in mice, we arranged a forty-two-day experimental schedule by using 210 mice for five senior skillful investigators and another five junior unskillful investigators to administer deionized water, per os, twice a day, in addition to ad libitum of deionized water and normal feed, to various groups of

Bing Bing Lin; Chih-Ching Lai; Keng-Kuang Chang; B. Pharm

1996-01-01

102

Nitrogen Utilization Efficiency: Relationships with Grain Yield, Grain Protein, and Yield-Related Traits in Rice  

Microsoft Academic Search

Rice (Oryza sativa L.) breeders have historically not included nitrogen utilization efficiency (NUE) as a selection criterion in breed- ing for cultivars, even though it has economic and ecological implica- tions. This study examined the significance and magnitude of variation in N content, NUE, N translocation ratio (NTR), and grain protein concentration among diverse rice genotypes. Fifteen rice genotypes were

Stanley Omar; Lloyd T. Wilson; James C. Medley; Shannon R. M. Pinson; Anna M. McClung; Joveno S. Lales

2006-01-01

103

A theoretical framework to study potassium utilization efficiency in response to withdrawal of potassium.  

PubMed

An important objective of plant research is to improve the efficiency in the utilization of major nutrients, particularly nitrogen, phosphorus, and potassium. Several definitions of internal nutrient utilization efficiency (NUE) have been proposed, but the theoretical consistence of their use has been poorly explored. Here, a non-mechanistic approach was developed to theoretically examine the dynamics of commonly used NUE indicators following complete potassium deprivation. This approach was used to study the sensitivity of NUE indicators to changes in the actual NUE (NUEa) of K(+) in virtual plants. Three empirically based models that differ in the relationship between NUE and the internal K(+) concentration were examined. Frequently used indicators (potassium use efficiency, utilization efficiency, physiological efficiency, and nutrient productivity) and two additional ones introduced here (accumulated productivity and physiological ratio) differed in their capacity to reflect differences in NUEa. They also exhibited large disparities in their temporal variation and in their responsiveness to the concentration of K(+) before the beginning of the deprivation period. According to this analysis, the simultaneous use of several indicators could help to refine plant breeding for high NUE. The data also suggest that a trade off between plant productivity and the time necessary to reduce the concentration of K(+) by half is inherent to the dynamics of plant systems. Finally, it is proposed that for some plant species selection for high NUEa would not always be in conflict with selection for improved relative plant performance in low K(+) environments. PMID:23963671

Moriconi, Jorge I; Santa-María, Guillermo E

2013-08-20

104

Protein requirements of bobwhite chicks for survival, growth and efficiency of feed utilization  

USGS Publications Warehouse

During the summer and fall of 1939 four experiments were conducted at the Patuxent Research Refuge, Bowie, Maryland, to determine the protein requirements of bobwhite chicks. A total of 816 chicks were used to compare six levels of protein, namely, 22,24,26, 28, 30, and 32 per cent.....From the three standpoints of survival, rate of growth, and efficiency of feed utilization for the first ten weeks of life, the 28 per cent level of protein gave the best results. During the ninth and tenth weeks, the highest efficiency of feed utilization was obtained on the 22 per cent level. The results indicate that after the birds have reached about twothirds of their mature weight, the difference in efficiency between a diet containing 28 per cent of protein and one containing 22 per cent may be small enough to justify, in the interest of economy, the use of a diet containing the lower percentage of protein.

Nestler, R.B.; Bailey, W.W.; McClure, H.E.

1942-01-01

105

Energy Efficient Ultra-Wideband Signaling for Cooperative Spectrum Sensing in Cognitive Radio  

Microsoft Academic Search

The reliable detection of unused spectrum while meeting a required probability of detecting primary user activity is a key functionality of cognitive radio systems. In cooperative spectrum sensing, the detection results of multiple cognitive ra- dios are combined to a global result with high reliability. In order to transmit the local decisions a signaling channel is required. It can be

Daniel Bielefeld; Gernot Fabeck; Milan Zivkovic; Rudolf Mathar

2011-01-01

106

Stimulating utilities to promote energy efficiency: Process evaluation of Madison Gas and Electric's Competition Pilot Program  

SciTech Connect

This report describes the process evaluation of the design and implementation of the Energy Conservation Competition Pilot (hereafter referred to as the Competition), ordered by the Public Service Commission of Wisconsin (PSCW) with a conceptual framework defined by PSCW staff for the Madison Gas and Electric (MGE) Company. This process evaluation documents the history of the Competition, describing the marketing strategies adopted by MGE and its competitors, customer service and satisfaction, administrative issues, the distribution of installed measures, free riders, and the impact of the Competition on MGE, its competitors, and other Wisconsin utilities. We also suggest recommendations for a future Competition, compare the Competition with other approaches that public utility commissions (PUCs) have used to motivate utilities to promote energy efficiency, and discuss its transferability to other utilities. 48 refs., 8 figs., 40 tabs.

Vine, E.; De Buen, O.; Goldfman, C.

1990-12-01

107

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

SciTech Connect

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?

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

1996-07-01

108

Triage of the autistic spectrum child utilizing the congruence of case management concepts and Orem's Nursing Theories.  

PubMed

The purpose of this project was to design and implement a case management framework for the benefit of children diagnosed with an autistic spectrum disorder (ASD). The process consisted of selecting two children exhibiting symptoms of an ASD and managing them across a continuum of care. Methodological structure was derived from case management standards of practice and Orem's Nursing Theories. Although some objectives sustained a slight delay because of variances, findings revealed successful outcomes based on progression toward measurable case management goals. The children were directed to appropriate school placements and habilitative therapies in an efficient manner. Their parents received support and education related to special needs children. The process yielded assurance that Orem's Nursing Theories and case management concepts articulate seamlessly within nursing care boundaries. PMID:12668924

Oliver, Catherine J

109

Decision factors affecting transmission and distribution efficiency improvements by Northwest electric utilities  

SciTech Connect

The principal objective of this report was to assess and document the attitude of Northwest electric utilities toward possible BPA conservation acquisition programs that may provide incentive(s) to reduce losses on T and D lines. Secondary objectives were to examine existing incentives for making such improvements, to categorize prior T and D efficiency improvements, and to examine factors affecting the decision-making process for system improvements. Much of the information presented in the report is derived from a survey administered during personal interviews at 29 Northwest electric utilities between November 1984 and January 1985.

Hendrickson, P.L.; Darwin, R.F.

1986-01-01

110

Study survey on a high-efficiency environment harmony type energy cascade utilization system  

NASA Astrophysics Data System (ADS)

The development trend of the technology necessitated in cascade utilization of energy in the regional scale is studied in terms of degree of its feasibility, development effects, etc. The technology for regional cascade utilization of energy has a system in which energy is recovered from various waste heat sources and unused energy sources, and the energy is stored and transported to the place of demand as the need arises. At the place of demand, the energy transported is converted in the forms suitable for utilizations to meet the demand. This technology includes heat recovery technology, heat transport/heat storage technology, and heat utilization technology, and what supports the base of these technologies is common base support technology, environmental load reduction technology, and energy systematizing technology. For materialization of the system, it is indispensable to develop technologies such as recovery/utilization of unused energy, matching of energy supply/demand, efficiency of the energy utilization system, and consideration of the environment, as well as to solve the problems such as supply responsibility, cost, pipe installation for waste heat transport, and city planning.

1992-03-01

111

Directed evolution of a highly efficient cellobiose utilizing pathway in an industrial Saccharomyces cerevisiae strain.  

PubMed

Balancing and increasing the flux through an engineered heterologous pathway in a target organism to achieve high yield and productivity remains an overwhelming challenge in metabolic engineering. Here we report a novel strategy combining directed evolution and promoter engineering for rapid and efficient multi-gene pathway optimization. As proof of concept, this strategy was applied to optimize a cellobiose utilizing pathway in an industrial Saccharomyces cerevisiae strain for highly efficient cellulosic biofuels production. The resulting strain exhibited significantly higher cellobiose consumption rate (6.41-fold) and ethanol productivity (6.36-fold) compared to its parent strain. This study also showed that both the ratios and absolute values of the expression levels of the genes in the cellobiose utilizing pathway play an important role in cellobiose uptake, and ?-glucose is likely one of the key factors affecting cellobiose metabolism. Biotechnol. Biotechnol. Bioeng. 2013;110: 2874-2881. © 2013 Wiley Periodicals, Inc. PMID:23616289

Yuan, Yongbo; Zhao, Huimin

2013-06-27

112

Development of a Design Support System that Can Efficiently Utilize Non-dominated Solutions  

Microsoft Academic Search

This paper proposes a new design support approach, which efficiently utilizes the information of many non-dominated solutions obtained from evolutionary multi-criterion optimization (EMO). The proposed approach consists of four mechanisms: grouping (clustering), reducing the number of candidates (selecting the representative solutions), dimensionality reduction, and estimation. Non-dominated solutions can be regarded as a beneficial subspace in whole search space, which have

Shinya Watanabe; Ryojiro Minato

2009-01-01

113

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

NASA Astrophysics Data System (ADS)

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.

Kobayakawa, Tomoaki; Hihara, Eiji; Hanazaki, Hirotaka

114

Importance of P uptake efficiency versus P utilization for wheat yield in acid and calcareous soils in Mexico  

Microsoft Academic Search

There are large agricultural areas in the world where wheat yields are limited by low phosphorus (P) availability. Breeding for P uptake and P utilization efficiency may reduce this problem. This study was conducted to determine the contribution of P uptake and utilization efficiency to grain yield of selected spring wheat genotypes in different environments. Thirty-eight semidwarf spring bread wheat

G. G. B. Manske; J. I. Ortiz-Monasterio; M. van Ginkel; R. M. González; R. A. Fischer; S. Rajaram; P. L. G. Vlek

2001-01-01

115

Privatization of state-owned electric utility in Thailand: Expected effects on economic efficiency  

SciTech Connect

This dissertation analyzes the prospects of improving the economic efficiency of electricity generation in Thailand by privatization. It examines the monopoly state-owned electric utility, its cost minimizing behavior, and the induced distortion in input prices. This study employs the generalized cost function to investigate the economic efficiency. The basic model follows the relative price efficiency analysis developed by Atkinson and Halvorsen (1984). The econometric models estimate and test the effects of the cost distortion on input utilization and on productivity growth. The existence of scale economies is tested. The empirical results reveal the efficient performance of EGAT under the current environment. One could not reject the efficiency of input choice. Productivity growth rose around 1.15 per cent per year during the study period. The total factor productivity (TFP) growth indicates no remarkably divergent predictions between the electricity generating sector and the industrial sector. This implies that EGAT's productivity grew at the same annual rate as that of the average for total privately owned manufacturing firms. It appears that the smaller power plants attained higher positive percentages of scale economies while the larger power plants did not. The minimum positive value of scale economies and the minimum average cost reported at 260 MW (computed at 65% load factor) of power plant size. The diseconomies of scale of the larger power plants and the U-shaped average cost curve support that the market could absorb several suppliers, particularly at the 260 MW size. The promotion of competition in the electricity generating sector could not be faulted in terms of sacrificing economies of scale. The recommendation drawn from this study is that there is no need to privatize EGAT. The price efficiency test could not reject the hypothesis that EGAT fulfill the objective of cost minimization.

Ruangrong, P.

1992-01-01

116

47 CFR 90.535 - Modulation and spectrum usage efficiency requirements.  

Code of Federal Regulations, 2011 CFR

...rate of 4.8 kbps per 6.25 kHz of bandwidth. (c) Transmitters designed to...non-voice) rate of 384 kbps per 150 kHz of bandwidth. (d) The following provisions apply...voice path per 6.25 kHz of spectrum bandwidth. (2) Licensees authorized...

2011-10-01

117

47 CFR 90.535 - Modulation and spectrum usage efficiency requirements.  

Code of Federal Regulations, 2012 CFR

...rate of 4.8 kbps per 6.25 kHz of bandwidth. (c) Transmitters designed to...non-voice) rate of 384 kbps per 150 kHz of bandwidth. (d) The following provisions apply...voice path per 6.25 kHz of spectrum bandwidth. (2) Licensees authorized...

2012-10-01

118

Efficient, visible organic light-emitting diodes utilizing a single polymer layer doped with quantum dots  

NASA Astrophysics Data System (ADS)

We demonstrate organic light-emitting diodes (OLEDs) using a single active layer consisting of CdSe/ZnS quantum dots (QDs) dispersed in poly (9,9-dioctylfluorene) (PFO). The diodes have an external quantum efficiency of ~0.5% and reach 0.1 A/cm2 at 6.5 V. These results are comparable to complex, multilayer QD OLEDs. Built-in potential measurements show that the QD valence levels are shifted to lower binding energy when compared to quantum confinement based estimates, and are close to PFO valence levels. Devices using red and green QDs emit predominantly from the QDs but the spectrum of blue QDs is perturbed by interactions with PFO.

Campbell, I. H.; Crone, B. K.

2008-01-01

119

Engineered Enterobacter aerogenes for efficient utilization of sugarcane molasses in 2,3-butanediol production.  

PubMed

Sugarcane molasses is considered to be a good carbon source for biorefinery due to its high sugar content and low price. Sucrose occupies more than half of the sugar in the molasses. Enterobacter aerogenes is a good host strain for 2,3-butanediol production, but its utilization of sucrose is not very efficient. To improve sucrose utilization in E. aerogenes, a sucrose regulator (ScrR) was disrupted from the genomic DNA. The deletion mutation increased the sucrose consumption rate significantly when sucrose or sugarcane molasses was used as a carbon source. The 2,3-butanediol production from sugarcane molasses by the mutant was enhanced by 60% in batch fermentation compared to that by the wild type strain. In fed-batch fermentation, 98.69 g/L of 2,3-butanediol production was achieved at 36 h. PMID:23644066

Jung, Moo-Young; Park, Bu-Soo; Lee, Jinwon; Oh, Min-Kyu

2013-04-08

120

Efficient utilization of launched threads on GPUs: The spherical harmonic transform as a case study  

NASA Astrophysics Data System (ADS)

Maximum utilization of hardware resources is crucial to leverage the enormous computational power of graphics processing units (GPUs). However, there lacks an effective metric to denote whether the launched threads are kept busy. To address this issue, we propose a metric called ETU to describe the efficiency of threads utilization. First, we execute several CUDA-SDK sample codes, with(out) double precision arithmetic, on two generations of GPUs so as to perform a preliminary validation of the ETU metric. Taking the spherical harmonic transform as an example, we then give two GPU implementations for Legendre transforms and check the relationship between ETU and application performance. Experimental results show that applications with larger ETU can usually achieve better performance, which is more accurate than occupancy proposed by NVIDIA. Finally, we select the GPU implementations with better performance to accelerate Legendre transforms in STSWM, which is a spectral transform shallow water model.

Lu, Feng-shun; Song, Jun-qiang; Lin, Wang-qun; Pang, Yu-fei; Ren, Kai-jun; Shi, Pei-chang

2013-11-01

121

An efficient & flexible algorithm for multimedia transmission over cognitive radio network (EFMCRN) based on bandwidth utilization and processing time  

Microsoft Academic Search

Cognitive radio is an emerging technology through which unlicensed users utilize the spectrum when primary users are in passive mode (i.e. don't transmit data). Real time transmission such as multimedia transmission plays an important role over cognitive radio networks. Normally a secondary user transmits its video over empty bands. When a primary user wants to switch on its band, the

S. Sana-e-Zainab

2011-01-01

122

Federal government, utility, manufacturer: A unique partnership for comprehensive water efficiency  

SciTech Connect

A partnership among the Federal government, a utility, and water efficient equipment manufacturers was developed in response to the Executive Order 12902, Energy and Efficiency in Federal Facilities, where water conservation is still a fairly undeveloped part of resource conservation in the Federal government. The Department of Energy`s Federal Energy Management Program (with the National Renewable Energy Laboratory) managed the project, bringing together the Environmental Protection Agency, General Services Administration and Bureau of Reclamation with Denver Water and four water use equipment manufacturers to install and test water-saving indoor and outdoor technologies at the Denver Federal Center. This paper will describe the process used to form this partnership and document the results and its potential impact.

Mayo, K.

1995-10-01

123

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

SciTech Connect

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.

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

2008-09-15

124

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

PubMed

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

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

2012-03-13

125

Effects of ethylenediaminetetraacetic acid on phytate phosphorus utilization and efficiency of microbial phytase in broiler chicks.  

PubMed

Previous studies have suggested that organic acids may improve P utilization in animals. To evaluate the ability of ethylenediaminetetraacetic acid (EDTA) to improve phytate P utilization and the possible synergistic effect between EDTA and microbial phytase (MP) an experiment was conducted using 360 Ross 308 broiler chicks. The experiment was carried out using a completely randomized design with a 3*2 factorial arrangement (0, 0.1 and 0.2% EDTA and 0 and 500 IU MP). Four replicate of 15 chicks per each were fed dietary treatments including (i) P-deficient basal diet [0.2% available phosphorus (aP)] (NC); (ii) NC + 500 IU MP per kilogram of diet; (iii) NC + 0.1% EDTA per kilogram of diet; (iv) NC + 0.1% EDTA and 500 IU MP per kilogram of diet; (v) NC + 0.2% EDTA per kilogram; and (vi) NC + 0.2% EDTA + 500 IU MP per kilogram of diet. Weight gain (WG), feed efficiency and serum Ca, P and alkaline phosphatase (ALP) were assessed. Addition of 0.2% EDTA to low aP diets resulted in significantly lower feed consumption (FC) and WG, but 0.1% EDTA did not depress WG compared to NC. Phytase supplementation of P-deficient diets significantly improved WG and feed efficiency, but it had no effect on FC. Microbial phytase supplementation significantly decreased ALP concentration. Results obtained in our study suggest no synergistic effect between phytase and EDTA in broiler chicks. PMID:18336413

Ebrahimnezhad, Y; Shivazad, M; Taherkhani, R; Nazeradl, K

2008-04-01

126

Efficient simultaneous fluorescence orientation, spectrum, and lifetime detection for single molecule dynamics  

NASA Astrophysics Data System (ADS)

We report on the simultaneous detection of the fluorescence lifetime, spectrum, and three-dimensional dipole orientation determination of single perylene diimide molecules deposited on a silica surface as a model system for studying fluorophore internal and orientational dynamics. We employ a multi-parameter detection scheme to demonstrate how jumps in the orientation of the molecule can be disentangled from spectral jumps, both leading to changes of the detected total fluorescence intensity. The fluorescence lifetime determined simultaneously from the same photons is also sensitive to the orientation of the dipole with respect to the interface between media with different refractive indices. The correlated changes of the lifetime and orientation we observe are in good agreement with theory.

Börner, Richard; Kowerko, Danny; Krause, Stefan; Borczyskowski, Christian von; Hübner, Christian G.

2012-10-01

127

Efficient simultaneous fluorescence orientation, spectrum, and lifetime detection for single molecule dynamics.  

PubMed

We report on the simultaneous detection of the fluorescence lifetime, spectrum, and three-dimensional dipole orientation determination of single perylene diimide molecules deposited on a silica surface as a model system for studying fluorophore internal and orientational dynamics. We employ a multi-parameter detection scheme to demonstrate how jumps in the orientation of the molecule can be disentangled from spectral jumps, both leading to changes of the detected total fluorescence intensity. The fluorescence lifetime determined simultaneously from the same photons is also sensitive to the orientation of the dipole with respect to the interface between media with different refractive indices. The correlated changes of the lifetime and orientation we observe are in good agreement with theory. PMID:23126703

Börner, Richard; Kowerko, Danny; Krause, Stefan; von Borczyskowski, Christian; Hübner, Christian G

2012-10-28

128

High efficiency resonance-based spectrum filters with tunable transmission bandwidth fabricated using nanoimprint lithography  

NASA Astrophysics Data System (ADS)

We propose a nanostructured color filter based on a metallic resonant waveguide structure capable of extremely high transmission efficiency. As an experimental demonstration, a blue and a red device were fabricated over a large area using nanoimprint lithography. Achieving transmission as high as 90% with a variable transmission bandwidth, these devices exhibit desirable features for numerous color filter applications.

Kaplan, Alex F.; Xu, Ting; Jay Guo, L.

2011-10-01

129

Instantaneous Shoreline Extraction Utilizing Integrated Spectrum and Shadow Analysis From LiDAR Data and High-resolution Satellite Imagery  

NASA Astrophysics Data System (ADS)

Shoreline delineation and shoreline change detection are expensive processes in data source acquisition and manual shoreline delineation. These costs confine the frequency and interval of shoreline mapping periods. In this dissertation, a new shoreline delineation approach was developed targeting on lowering the data source cost and reducing human labor. To lower the cost of data sources, we used the public domain LiDAR data sets and satellite images to delineate shorelines without the requirement of data sets being acquired simultaneously, which is a new concept in this field. To reduce the labor cost, we made improvements in classifying LiDAR points and satellite images. Analyzing shadow relations with topography to improve the satellite image classification performance is also a brand-new concept. The extracted shoreline of the proposed approach could achieve an accuracy of 1.495 m RMSE, or 4.452m at the 95% confidence level. Consequently, the proposed approach could successfully lower the cost and shorten the processing time, in other words, to increase the shoreline mapping frequency with a reasonable accuracy. However, the extracted shoreline may not compete with the shoreline extracted by aerial photogrammetric procedures in the aspect of accuracy. Hence, this is a trade-off between cost and accuracy. This approach consists of three phases, first, a shoreline extraction procedure based mainly on LiDAR point cloud data with multispectral information from satellite images. Second, an object oriented shoreline extraction procedure to delineate shoreline solely from satellite images; in this case WorldView-2 images were used. Third, a shoreline integration procedure combining these two shorelines based on actual shoreline changes and physical terrain properties. The actual data source cost would only be from the acquisition of satellite images. On the other hand, only two processes needed human attention. First, the shoreline within harbor areas needed to be manually connected, for its length was less than 3% of the total shoreline length in our dataset. Secondly, the parameters for satellite image classification needed to be manually determined. The need for manpower was significantly less compared to the ground surveying or aerial photogrammetry. The first phase of shoreline extraction was to utilize Normalized Difference Vegetation Index (NDVI), Mean-Shift segmentation on the coordinate (X, Y, Z), and attributes (multispectral bands from satellite images) of the LiDAR points to classify each LiDAR point into land or water surface. Boundary of the land points were then traced to create the shoreline. The second phase of shoreline extraction solely from satellite images utilized spectrum, NDVI, and shadow analysis to classify the satellite images into classes. These classes were then refined by mean-shift segmentation on the panchromatic band. By tracing the boundary of the water surface, the shoreline can be created. Since these two shorelines may represent different shoreline instances in time, evaluating the changes of shoreline was the first to be done. Then an independent scenario analysis and a procedure are performed for the shoreline of each of the three conditions: in the process of erosion, in the process of accession, and remaining the same. With these three conditions, we could analysis the actual terrain type and correct the classification errors to obtain a more accurate shoreline. Meanwhile, methods of evaluating the quality of shorelines had also been discussed. The experiment showed that there were three indicators could best represent the quality of the shoreline. These indicators were: (1) shoreline accuracy, (2) land area difference between extracted shoreline and ground truth shoreline, and (3) bias factor from shoreline quality metrics.

Lee, I.-Chieh

130

Genome Sequence of the Thermophilic Strain Bacillus coagulans XZL4, an Efficient Pentose-Utilizing Producer of Chemicals  

PubMed Central

Bacillus coagulans XZL4 is an efficient pentose-utilizing producer of important platform compounds, such as l-lactic acid, 2,3-butanediol, and acetoin. Here we present a 2.8-Mb assembly of its genome. Simple and efficient carbohydrate metabolism systems, especially the transketolase/transaldolase pathway, make it possible to convert pentose sugars to products at high levels.

Su, Fei; Xu, Ke; Zhao, Bo; Tai, Cui; Tao, Fei; Tang, Hongzhi; Xu, Ping

2011-01-01

131

Development of a Design Support System that Can Efficiently Utilize Non-dominated Solutions  

NASA Astrophysics Data System (ADS)

This paper proposes a new design support approach, which efficiently utilizes the information of many non-dominated solutions obtained from evolutionary multi-criterion optimization (EMO). The proposed approach consists of four mechanisms: grouping (clustering), reducing the number of candidates (selecting the representative solutions), dimensionality reduction, and estimation. Non-dominated solutions can be regarded as a beneficial subspace in whole search space, which have the feature of being non-inferior to other solutions. Therefore, we think the proposed approach can be used to estimate the characteristics of a problem through the interaction with the designer. In this paper, we examine the characteristics and effectiveness of the proposed approach through computational experiments on a design problem of a counter rotating axial fan turbojet engine. A counter rotating axial fan turbojet engine with two spools is chosen for the design target of the present study. We handle this task as a seven-objective design problem.

Watanabe, Shinya; Minato, Ryojiro

132

Area utilization efficiency of a sloping heliostat system for solar concentration.  

PubMed

Area utilization efficiency (AUE) is formulated for a sloping heliostat system facing any direction. The effects of slope shading, incidence factor, sun shading, and tower blocking by the mirrors are all taken into account. Our results show that annually averaged AUEs calculated for heliostat systems (1) increase with tower height at low slope angles but less rapidly at high slopes, (2) increase monotonically with slope angle and saturate at large slopes for systems facing due south, (3) reach a maximum at a certain slope for systems facing other directions than due south, and (4) drop sharply at slopes greater than a certain value for systems facing due east or west due to slope shading effect. The results are useful for solar energy collection on nonflat terrains. PMID:18195827

Wei, L Y

1983-02-15

133

High efficient illumination system utilizing light-guide and white light LED for document scanner application  

NASA Astrophysics Data System (ADS)

Design and evaluation of new illumination system utilizing white light emitting diode (LED) and plastic light-guide for letter-size (216mm width) document scanner and copier have been performed. We investigated the best condition for illumination on document plane through the optical analysis of scanner imaging system. To compensate the relative illumination fall-off caused by imaging lens, illumination on main-direction was designed to edge enhanced distribution. The illumination on sub-direction was designed to flat-top shape for stable performance against mechanical displacement of optics. The light-guide was designed dual-angled sidewalls for the decrease of light leakage and the increase of the degree of freedom for illumination shaping. The rear area of a light-guide is formed with crossed micro-prism patterns to axial direction to induce scattering of guided light, and the front area is formed with lens-shape for efficient lighting. Total 12 parameters were used for the optimization of design, and the various relationships between parameters and performances were also investigated. The optical characteristics of the proposed illumination system utilizing a white LED and light-guide, fabricated by mold process, were also experimentally evaluated in terms of illumination distribution against main- and sub-direction on image plane. They showed excellent agreement with simulated result and showed good performance of uniformity above 91%, and 89% in sub-direction and main-direction, respectively.

Kim, Kyoung-Rok; Kim, Hyunsurk; Kim, Hyeongchae

2008-08-01

134

Utilization of squid pen for the efficient production of chitosanase and antioxidants through prolonged autoclave treatment.  

PubMed

We have developed a culture system for efficient production of chitosanase by Bacillus sp. TKU004. TKU004 was cultivated by using squid pen powder as the sole carbon/nitrogen source. The effects of autoclave treatments of the medium on the production of chitosanase were investigated. Autoclave treatment of squid pen powder for 45 min remarkably promoted enzyme productivity. When the culture medium containing an initial squid pen powder concentration of 3% was autoclaved for 45 min, the chitosanase activity was optimal and reached 0.14-0.16 U/mL. In addition, extracellular surfactant-stable chitosanase was purified from the TKU004 culture supernatant. The antioxidant activity of TKU004 culture supernatant was determined through the scavenging ability of DPPH, with 70% per mL. With this method, we have shown that marine wastes can be utilized efficiently through prolonged autoclave treatments to generate a high value-added product, and have revealed its hidden potential in the production of functional foods. PMID:19342008

Wang, San-Lang; Wu, Pei-Chen; Liang, Tzu-Wen

2009-03-17

135

Federal Energy Efficiency through Utility Partnerships: Federal Energy Management Program (FEMP) Program Overview Fact Sheet.  

National Technical Information Service (NTIS)

This Utility Program Overview describes how the Federal Energy Management Program (FEMP) utility program assists Federal energy managers. The document identifies both a utility financing mechanism and FEMP technical assistance available to support agencie...

D. Beattie M. Wolfson

2001-01-01

136

EASY-GOING deconvolution: Automated MQMAS NMR spectrum analysis based on a model with analytical crystallite excitation efficiencies.  

PubMed

The EASY-GOING deconvolution (EGdeconv) program is extended to enable fast and automated fitting of multiple quantum magic angle spinning (MQMAS) spectra guided by evolutionary algorithms. We implemented an analytical crystallite excitation model for spectrum simulation. Currently these efficiencies are limited to two-pulse and z-filtered 3QMAS spectra of spin 3/2 and 5/2 nuclei, whereas for higher spin-quantum numbers ideal excitation is assumed. The analytical expressions are explained in full to avoid ambiguity and facilitate others to use them. The EGdeconv program can fit interaction parameter distributions. It currently includes a Gaussian distribution for the chemical shift and an (extended) Czjzek distribution for the quadrupolar interaction. We provide three case studies to illustrate EGdeconv's capabilities for fitting MQMAS spectra. The EGdeconv program is available as is on our website http://egdeconv.science.ru.nl for 64-bit Linux operating systems. PMID:23376481

Grimminck, Dennis L A G; van Meerten, Bas; Verkuijlen, Margriet H W; van Eck, Ernst R H; Meerts, W Leo; Kentgens, Arno P M

2013-01-04

137

EASY-GOING deconvolution: Automated MQMAS NMR spectrum analysis based on a model with analytical crystallite excitation efficiencies  

NASA Astrophysics Data System (ADS)

The EASY-GOING deconvolution (EGdeconv) program is extended to enable fast and automated fitting of multiple quantum magic angle spinning (MQMAS) spectra guided by evolutionary algorithms. We implemented an analytical crystallite excitation model for spectrum simulation. Currently these efficiencies are limited to two-pulse and z-filtered 3QMAS spectra of spin 3/2 and 5/2 nuclei, whereas for higher spin-quantum numbers ideal excitation is assumed. The analytical expressions are explained in full to avoid ambiguity and facilitate others to use them. The EGdeconv program can fit interaction parameter distributions. It currently includes a Gaussian distribution for the chemical shift and an (extended) Czjzek distribution for the quadrupolar interaction. We provide three case studies to illustrate EGdeconv's capabilities for fitting MQMAS spectra. The EGdeconv program is available as is on our website http://egdeconv.science.ru.nl for 64-bit Linux operating systems.

Grimminck, Dennis L. A. G.; van Meerten, Bas; Verkuijlen, Margriet H. W.; van Eck, Ernst R. H.; Leo Meerts, W.; Kentgens, Arno P. M.

2013-03-01

138

Development and application of programs to measure modulation transfer function, noise power spectrum and detective quantum efficiency.  

PubMed

This project aimed to produce programs to calculate the modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE) of digital X-ray systems, given a suitable digital image. The MTF was calculated using the edge technique and the NPS was calculated from a flat field image. Both programs require a suitably edited DICOM image as input. The DQE was then calculated from the output of MTF and NPS programs. This required data external to the DQE program to estimate the number of quanta per mm2 in the beam which formed the NPS image. All three programs run independent of each other on a PC and require no special software to be installed. Results for MTF, NPS and DQE for a Philips AC3 CR system are presented. In addition, the results for MTF from a Siemens Duo CT scanner with a specially designed PTFE edge are also shown. PMID:16461517

Padgett, R; Kotre, C J

2006-02-03

139

Exploring the Utility of Narrative Analysis in Diagnostic Decision Making: Picture-Bound Reference, Elaboration, and Fetal Alcohol Spectrum Disorders  

ERIC Educational Resources Information Center

Purpose: To evaluate classification accuracy and clinical feasibility of a narrative analysis tool for identifying children with a fetal alcohol spectrum disorder (FASD). Method: Picture-elicited narratives generated by 16 age-matched pairs of school-aged children (FASD vs. typical development [TD]) were coded for semantic elaboration and…

Thorne, John C.; Coggins, Truman E.; Olson, Heather Carmichael; Astley, Susan J.

2007-01-01

140

Utility of the VITEK 2 Advanced Expert System for Identification of Extended-Spectrum Lactamase Production in Enterobacter spp  

Microsoft Academic Search

Accurate identification of extended-spectrum -lactamase (ESBL) production is essential for the appropriate reporting of antimicrobial susceptibility results, since ESBLs render peni- cillins, cephalosporins, and aztreonam inadequate for treat- ment of serious infections (2). While guidelines exist for ESBL detection in Escherichia coli, Klebsiella spp., and Proteus mira- bilis isolates only (2), these enzymes are produced by a wide variety of

Mitchell J. Schwaber; Shiri Navon-Venezia; Inna Chmelnitsky; Azita Leavitt; David Schwartz; Yehuda Carmeli

2006-01-01

141

Discharge flow-photoionization mass spectrometric study of HOI: Photoionization efficiency spectrum and ionization energy  

SciTech Connect

Photoionization efficiency (PIE) spectra of HOI were measured over the wavelength range {lambda} = 115-130 nm and in the ionization threshold region, {lambda} = 123-129 nm, using a discharge flow-photoionization mass spectrometer apparatus coupled to a synchrotron radiation source. HOI was generated, in situ but in varying amounts, by three separate reactions: OH + I{sub 2}; OH + CF{sub 3}I; O({sup 3}P) + C{sub 2}H{sub 5}I. The PIE spectra displayed steplike behavior near threshold, and the HO-I stretching frequency in the cation was determined to be 702 {+-} 60 cm{sup -1}. Even though the present result appears to be the first reported determination of IE(HOI), the experimental value is compared to an estimated value previously derived via a trend analysis and it is considered in terms of trends in the series IE(HOX), where X = F, Cl, Br, and I. Based on the value for IE(HOI) derived in the present study, a value for IE(IO) = 9.66 {+-} 0.10 eV has been predicted. 37 refs., 4 figs., 3 tabs.

Monks, P.S.; Stief, L.J. [NASA/Goddard Space Flight Center, Greenbelt, MD (United States); Tardy, D.C. [Univ. of Iowa, Iowa City, IA (United States); Liebman, J.F. [Univ. of Maryland, Baltimore, MD (United States); Zhang, Z.; Kuo, S.C.; Klemm, R. B. [Brookhaven National Lab., Upton, NY (United States)

1995-11-09

142

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

Microsoft Academic Search

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

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

2000-01-01

143

Establishing an Efficient Way to Utilize the Drought Resistance Germplasm Population in Wheat  

PubMed Central

Drought resistance breeding provides a hopeful way to improve yield and quality of wheat in arid and semiarid regions. Constructing core collection is an efficient way to evaluate and utilize drought-resistant germplasm resources in wheat. In the present research, 1,683 wheat varieties were divided into five germplasm groups (high resistant, HR; resistant, R; moderate resistant, MR; susceptible, S; and high susceptible, HS). The least distance stepwise sampling (LDSS) method was adopted to select core accessions. Six commonly used genetic distances (Euclidean distance, Euclid; Standardized Euclidean distance, Seuclid; Mahalanobis distance, Mahal; Manhattan distance, Manhat; Cosine distance, Cosine; and Correlation distance, Correlation) were used to assess genetic distances among accessions. Unweighted pair-group average (UPGMA) method was used to perform hierarchical cluster analysis. Coincidence rate of range (CR) and variable rate of coefficient of variation (VR) were adopted to evaluate the representativeness of the core collection. A method for selecting the ideal constructing strategy was suggested in the present research. A wheat core collection for the drought resistance breeding programs was constructed by the strategy selected in the present research. The principal component analysis showed that the genetic diversity was well preserved in that core collection.

Wang, Jiancheng; Guan, Yajing; Wang, Yang; Zhu, Liwei; Wang, Qitian; Hu, Qijuan; Hu, Jin

2013-01-01

144

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

NASA Astrophysics Data System (ADS)

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.

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

2011-05-01

145

Highly efficient SO? absorption and its subsequent utilization by weak base/polyethylene glycol binary system.  

PubMed

A binary system consisting of polyethylene glycol (PEG, proton donor)/PEG-functionalized base with suitable basicity was developed for efficient gas desulfurization (GDS) and can be regarded as an alternative approach to circumvent the energy penalty problem in the GDS process. High capacity for SO(2) capture up to 4.88 mol of SO(2)/mol of base was achieved even under low partial pressure of SO(2). Furthermore, SO(2) desorption runs smoothly under mild conditions (N(2), 25 °C) and no significant drop in SO(2) absorption was observed after five-successive absorption-desorption cycles. On the other hand, the absorbed SO(2) by PEG(150)MeIm/PEG(150), being considered as the activated form of SO(2), can be directly transformed into value-added chemicals under mild conditions, thus eliminating the energy penalty for SO(2) desorption and simultaneously realizing recycle of the absorbents. Thus, this SO(2) capture and utilization (SCU) process offers an alternative way for GDS and potentially enables the SO(2) conversion from flue gas to useful chemicals as a value-added process. PMID:23323771

Yang, Zhen-Zhen; He, Liang-Nian; Zhao, Ya-Nan; Yu, Bing

2013-01-25

146

Recycling Limestone for SO2 Absorption: Pollutant-absorbing material is utilized more efficiently.  

National Technical Information Service (NTIS)

This citation summarizes a one-page announcement of technology available for utilization. Partially reacted limestone used for removing sulfur dioxide during the fluidized combustion of coal can be reactivated by hydration. This increased utilization woul...

1983-01-01

147

Utility and Performance Relative to Consumer Product Energy Efficiency Standards. Final Technical Report.  

National Technical Information Service (NTIS)

An investigation of the relative utility and performance of nine major household consumer products covered by the Energy Policy and Conservation Act is summarized. The objective was to define the terms utility and performance, to recommend methods for qua...

J. L. Coggins

1979-01-01

148

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

SciTech Connect

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.

Hopper, Nicole; Goldman, Charles; Schlegal, Jeff

2006-08-01

149

Changes in efficiency and resource utilization after increasing experience with double balloon enteroscopy  

PubMed Central

AIM: To investigate changes in efficiency and resource utilization as a single endoscopist’s experience increased with each subsequent 100 double balloon enteroscopy (DBE) procedures. METHODS: We reviewed consecutive DBE procedures performed by a single endoscopist at our center over 4 years. DBE was employed when the clinician deemed the procedure was needed for disease management. The approach (oral, anal or both) was chosen based on suspected location of the target lesion. All DBE was performed in a standard endoscopy room with a portable fluoroscopy unit. Fluoroscopy was used to aid in shortening the small intestine and reducing bowel loops. For oral DBE, measurements were taken from the incisors. For anal DBE, measurements were taken from the anal verge. Enteroscopy continued until the target lesion was reached, until the entire small intestine was examined, or until no further progress was deemed possible. The length of small intestine examined (cm), procedure duration (min), and fluoroscopy time (s) were analyzed for sequential groups of 100 DBE. Sub-groups of diagnostic and therapeutic procedures were analyzed using multivariable linear regression. RESULTS: 802 consecutive DBE procedures were analyzed. For oral DBE, median [interquartile range (IQR)] length of small bowel examined was 230.8 cm (range: 210-248 cm) and for anal DBE was 143.5 cm (range: 100-180 cm). No significant increase in length examined was noted for either the oral or anal approach with advancing position in series. In terms of duration of procedure, the median (IQR) for oral DBE was 86 min (range: 71-105 min) and for anal DBE was 81.3 min (range: 67-105 min). When comparing by the position in series, there was a significant (P value < 0.001) decrease in procedure duration for both upper and lower procedures with increasing experience. Median (IQR) time of exposure to fluoroscopy for oral DBE was 190 s (114-275) compared to anal DBE which was 196.4 s (312-128). This represented a significant (P value < 0.001) decrease in the amount of fluoroscopy used with increasing position in series. For both oral and anal DBE, fluoroscopy time was reduced by greater than 50% over the course of 802 total procedures performed. Sub-group analysis was conducted on therapeutic and diagnostic groups. Out of 802 procedures, a total of 434 were considered therapeutic. Argon plasma coagulation was by far the most common therapeutic intervention performed. There was no evidence of a difference in length examined or fluoroscopy exposure among oral DBE for diagnostic and therapeutic procedures, P = 0.91 and P = 0.32 respectively. The median (IQR) for length was 235 cm (range: 178-280 cm) for diagnostic vs 230 cm (range: 180-275 cm) for therapeutic procedures; additionally, fluoroscopy time median (IQR) was 180 s (range: 110-295 s) and 162 s (range: 102-263 s) for no intervention and intervention. However, there was a significant difference in procedure duration among oral DBE (P < 0.001). The median (IQR) was 80 min (range: 60-97 min) and 94 min (range: 77-110 min) for diagnostic and therapeutic interventions respectively. CONCLUSION: For a single endoscopist, increased DBE experience with number of performed procedures is associated with increased efficiency and decreased resource utilization.

Patel, Neal C; Palmer, William C; Gill, Kanwar R; Cangemi, David; Diehl, Nancy; Stark, Mark E

2013-01-01

150

Simulation of the Metabolism of Absorbed Energy Yielding Nutrients in Young Sheep: Efficiency of Utilization of LJpidand Amino Acid1  

Microsoft Academic Search

A previously described mathematical model that simulates the metabolism of absorbed nutrients in a sheep weighing 25 kg was used to examine the effects of altering lipid and amino acid absorption, and the potential of the animal to deposit protein on the efficiency of utilization (k,) of metabolizable energy. The predicted k, of energy from lipid added to several diets

JOHN L BLACK; MARGARET GILL; JOHN H. M. THORNLEY; DAVIDE. BEEVER; JOHN D. OLDHAMf

151

Development of Technologies for a High Efficiency, Very Low Emission, Diesel Engine for Light Trucks and Sport Utility Vehicles  

Microsoft Academic Search

Cummins Inc., in partnership with the Department of Energy, has developed technology for a new highly efficient, very low emission, diesel engine for light trucks and sport utility vehicles. This work began in April 1997, and started with very aggressive goals for vehicles in the 5751 to 8500 pound GCW weight class. The primary program goals were as follows: (1)

Stang; John H

2005-01-01

152

Development of Technologies for a High Efficiency, Very Low Emission, Diesel Engine for Light Trucks and Sport Utility Vehicles  

Microsoft Academic Search

Cummins Inc., in partnership with the Department of Energy, has developed technology for a new highly efficient, very low emission, diesel engine for light trucks and sport utility vehicles. This work began in April 1997, and started with very aggressive goals for vehicles in the 5751 to 8500 pound GCW weight class. The primary program goals were as follows:;\\u000a;

Stang; John H

1997-01-01

153

Efficiency of energy utilization: effects of diet composition on body composition and mammary neoplasia  

SciTech Connect

Multiple interactions between the efficiency of utilization of dietary fat and carbohydrate energy, energy intake changes in body composition and 7,12-dimethylbenz(a)anthracene (DMBA) DMBA-induced mammary tumorigenesis were examined using female F-344 rats. The rats were fed ad libitum a semipurified diet containing 5% corn oil (LF) from weaning to 50 d of age at which each was given, by gavage, 65 mg DMBA/kg body weight. The rats were randomly assigned to diets containing 5% 17.5% (MF) and 30% (HF) corn oil. All diets were balanced with respect per unit of energy in terms of protein, vitamins, minerals and fiber. For 28 d post-DMBA, the rats were fed 40 or 42 kcal daily and thereafter, diet was provided ad libitium. Daily energy intakes were recorded throughout the study. The mean energy intakes during the first 35 wk were: LF, 240 +/- 12.3 kcal/wk; MF, 237 +/- 11.7 kcal/wk; and HF, 237 +/- 11.1 kcal/wk. Body weight at 35 wk were: LF, 196 +/- 9.5 g; MF, 206 +/- 13.9 g; and HF, 210 +/- 20.6 g. No differences in tumor incidence (LF, 55%; MF, 46%; HF, 51%), tumors/group (LF, 24; MF, 28; HF, 25) and tumors/tumor-bearing rat (LF, 1.3 +/- 0.7; MF 1.6 +/- 1.0;p HF, 1.2 +/- 0.4) were noted. Within dietary groups tumor incidence was positively correlated with energy intake. However, there were no differences among the various parameters between dietary groups at any energy intake level. Body compositions were monitored during this study. The body fat mass and % carcass weight increased in parallel with the % dietary fat. Concomitantly, % lean body and, to a lesser extent lean body mass decreased. Both body size and body composition, influenced by energy intake and retention, affected the response to DMBA.

Boissonneault, G.A.; Elson, C.E.; Pariza, M.W.

1986-03-05

154

Isolation and characterization of a mutant recombinant Saccharomyces cerevisiae strain with high efficiency xylose utilization.  

PubMed

A recombinant xylose-utilizing Saccharomyces cerevisiae strain carrying one copy of heterologous XYL1 and XYL2 from Pichia stipitis and endogenous XKS1 under the control of the TDH3 promoter in the chromosomal DNA was constructed from the industrial haploid yeast strain NAM34-4C, which showed thermotolerance and acid tolerance. The recombinant S. cerevisiae strain SCB7 grew in minimal medium containing xylose as the sole carbon source, and its shortest generation time (Gshort) was 5 h. From this strain, four mutants showing rapid growth (Gshort = 2.5 h) in the minimal medium were isolated. The mutants carried four mutations that were classified into three linkage groups. Three mutations were dominant and one mutation was recessive to the wild type allele. The recessive mutation was in the PHO13 gene encoding para-nitrophenyl phosphatase. The other mutant genes were not linked to TAL1 gene encoding transaldolase. When the mutants and their parental strain were used for the batch fermentation in a complex medium at pH 4.0 containing 30 g/L xylose at 35°C with shaking (60 rpm) and an initial cell density (Absorbance at 660 nm) of 1.0, all mutants showed efficient ethanol production and xylose consumption from the early stage of the fermentation culture. In two mutants, within 24 h, 4.8 g/L ethanol was produced, and the ethanol yield was 47%, which was 1.4 times higher than that achieved with the parental strain. The xylose concentration in the medium containing the mutant decreased linearly at a rate of 1 g/L/h until 24 h. PMID:23810666

Tomitaka, Masataka; Taguchi, Hisataka; Fukuda, Kohsai; Akamatsu, Takashi; Kida, Kenji

2013-06-27

155

Monte Carlo analyses of X-ray absorption, noise, and detective quantum efficiency considering therapeutic X-ray spectrum in portal imaging detector  

Microsoft Academic Search

The Bremsstrahlung spectrum from a 6-MV linear accelerator (LINAC) was obtained and used as an input X-ray source in the simulation to estimate several important physical quantities of the detector in a therapeutic X-ray portal imaging system, such as quantum and energy absorption efficiencies. Swank factor, and detective quantum efficiency (DQE). In addition, we have obtained a spatial distribution of

Gyuseong Cho; Ho Kyung Kim; Yong Hyun Chung; Do Kyung Kim; Hyoung Koo Lee; Tae Suk Suh; Koan Sik Joo

2001-01-01

156

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  

Microsoft Academic Search

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

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

2008-01-01

157

Efficient light coupling into in-plane semiconductor nanomembrane photonic devices utilizing a sub-wavelength grating coupler.  

PubMed

We report a subwavelength grating (SWG) coupler for coupling light efficiently into in-plane semiconductor nanomembrane photonic devices for the first time. The SWG coupler consists of a periodic array of rectangular trenches fabricated on a silicon nanomembrane (SiNM) transferred onto a glass substrate. At a wavelength of 1555.56 nm, the coupling efficiency of the fabricated 10 µm wide, 17.1 µm long SWG is 39.17% (-4.07 dB), with 1 dB and 3 dB bandwidths of 29 nm and 57 nm, respectively. Peak efficiency varies by 0.26 dB when measuring 5 fabricated grating pairs. Coupling efficiency can further be improved with an improved SiNM transfer process. Such high efficiency couplers allow for the successful realization of a plethora of hybrid photonic devices utilizing nanomembrane technology. PMID:23037113

Subbaraman, Harish; Xu, Xiaochuan; Covey, John; Chen, Ray T

2012-08-27

158

Analyzing the Energy Utilization Efficiency of Renewable Energy Resources. Part 1: Energy Analysis Method  

Microsoft Academic Search

Energy consumption depends mainly on the available amounts of local resources, which are closely connected with the present rural economy and living standards. Recently, there has been increasing interest in using energy and exergy modeling techniques for energy utilization assessments in order to attain energy savings, and hence financial savings. The energy utilization of a country can be evaluated using

Zafer Utlu; Arif Hepbasli

2006-01-01

159

Efficiency of photosynthesis in a Chl d-utilizing cyanobacterium is comparable to or higher than that in Chl a-utilizing oxygenic species.  

PubMed

The cyanobacterium Acaryochloris marina uses chlorophyll d to carry out oxygenic photosynthesis in environments depleted in visible and enhanced in lower-energy, far-red light. However, the extent to which low photon energies limit the efficiency of oxygenic photochemistry in A. marina is not known. Here, we report the first direct measurements of the energy-storage efficiency of the photosynthetic light reactions in A. marina whole cells, and find it is comparable to or higher than that in typical, chlorophyll a-utilizing oxygenic species. This finding indicates that oxygenic photosynthesis is not fundamentally limited at the photon energies employed by A. marina, and therefore is potentially viable in even longer-wavelength light environments. PMID:21708123

Mielke, S P; Kiang, N Y; Blankenship, R E; Gunner, M R; Mauzerall, D

2011-06-25

160

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

NASA Astrophysics Data System (ADS)

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.

Kobayakawa, Tomoaki; Hihara, Eiji; Hanazaki, Hirotaka

161

Improved full spectrum cloudy scene simulation  

Microsoft Academic Search

This paper will discuss recent improvements made to the MCScene code, a high fidelity model for full optical spectrum (UV through LWIR) hyperspectral image (HSI) simulation. MCScene provides an accurate, robust, and efficient means to generate HSI scenes for algorithm validation. MCScene utilizes a Direct Simulation Monte Carlo approach for modeling 3D atmospheric radiative transfer (RT) including full treatment of

Robert Sundberg; Steven Richtsmeier; Raymond Haren

2008-01-01

162

Improved Full Spectrum Cloudy Scene Simulation  

Microsoft Academic Search

This paper will discuss recent improvements made to the MCScene code, a high fidelity model for full optical spectrum (UV through LWIR) hyperspectral image (HSI) simulation. MCScene provides an accurate, robust, and efficient means to generate HSI scenes for algorithm validation. MCScene utilizes a Direct Simulation Monte Carlo approach for modeling 3D atmospheric radiative transfer (RT) including full treatment of

Robert Sundberg; Steven Richtsmeier; Raymond Haren

2009-01-01

163

Process utilized oligo-?-cyclodextrin substituted agarose gel medium for efficient purification of paclitaxel from Taxus cuspidata  

Microsoft Academic Search

An efficient and economical process utilized oligo-?-cyclodextrin substituted agarose gel medium has been developed for paclitaxel recovery and purification directly from the plant materials of Taxus cuspidata. The process is a combination of extraction, alkaline Al2O3 chromatography step, oligo-?-cyclodextrin substituted agarose gel column chromatography which employed a novel oligo-?-cyclodextrin-Sepharose HP as the packing material, and crystallization. The Al2O3 normal-phase chromatography

Li Yang; Tianwei Tan; Liqun Zhang

2009-01-01

164

Combinatorial Design of a Highly Efficient Xylose-Utilizing Pathway in Saccharomyces cerevisiae for the Production of Cellulosic Biofuels  

PubMed Central

Balancing the flux of a heterologous metabolic pathway by tuning the expression and properties of the pathway enzymes is difficult, but it is critical to realizing the full potential of microbial biotechnology. One prominent example is the metabolic engineering of a Saccharomyces cerevisiae strain harboring a heterologous xylose-utilizing pathway for cellulosic-biofuel production, which remains a challenge even after decades of research. Here, we developed a combinatorial pathway-engineering approach to rapidly create a highly efficient xylose-utilizing pathway for ethanol production by exploring various combinations of enzyme homologues with different properties. A library of more than 8,000 xylose utilization pathways was generated using DNA assembler, followed by multitiered screening, which led to the identification of a number of strain-specific combinations of the enzymes for efficient conversion of xylose to ethanol. The balancing of metabolic flux through the xylose utilization pathway was demonstrated by a complete reversal of the major product from xylitol to ethanol with a similar yield and total by-product formation as low as 0.06 g/g xylose without compromising cell growth. The results also suggested that an optimal enzyme combination depends on not only the genotype/phenotype of the host strain, but also the sugar composition of the fermentation medium. This combinatorial approach should be applicable to any heterologous pathway and will be instrumental in the optimization of industrial production of value-added products.

Kim, Byoungjin; Du, Jing; Eriksen, Dawn T.

2013-01-01

165

Bioengineering and management for efficient phosphorus utilization in crops and pastures.  

PubMed

Phosphorus (P) is one of the three macronutrients for plants. Because of its low mobility and high fixation in soils, low P availability is a worldwide constraint for crop productivity. Molecular biology provides great opportunities to improve P efficiency in plants. However, transgenic plants cannot be commercialized before integrating all the knowledge on bottlenecks for improving P efficiency of crops/pastures. This review intends to summarize the main strategies of bioengineering to improve P efficiency of crops/pastures, including conventional and molecular assisted breeding, identification and application of key genes for biotech plants. It highlights recent advances in the understanding of improving P efficiency through the integration of bioengineering with P fertilization and cultivation management. PMID:22445911

Tian, Jiang; Wang, Xiurong; Tong, Yiping; Chen, Xinping; Liao, Hong

2012-03-23

166

(Energy efficiency of the computerized utilities energy monitor and control system)  

SciTech Connect

The travelers, representing the ORNL Energy Division, Efficiency and Renewables Research Section, conducted an in-depth evaluation of the CUMACS/EMCS installed at the 26th Support Group, USAREUR. This endeavor included an evaluation of the overall performance of this system including operations maintenance and end-user impact. System energy efficiency in terms of projected and actual energy and cost savings were analyzed. Conclusions and preliminary recommendations based on this evaluation were also formulated.

Broders, M.A.; McConnell, B.W.

1990-12-17

167

Simian immunodeficiency virus utilizes human and sooty mangabey but not rhesus macaque STRL33 for efficient entry.  

PubMed

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 studies 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 with comparable efficiencies. Strikingly, however, only human STRL33 (huSTRL33), not rhesus macaque STRL33 (rhSTRL33), functioned efficiently as an entry cofactor for a variety of isolates of SIVmac and SIV from sooty mangabeys. A single amino acid substitution of S30R in huSTRL33 impaired coreceptor activity, and the reverse change in rhSTRL33 greatly increased coreceptor activity. In comparison, species-specific sequence variations in N-terminal tyrosines in STRL33 had only moderate effects on SIV entry. These results show that a serine residue located just outside of the cellular membrane in the N terminus of STRL33 is critical for SIV coreceptor function. Interestingly, STRL33 derived from sooty mangabeys, a natural host of SIV, also contained a serine at the corresponding position and was used efficiently as an entry cofactor. These results suggest that STRL33 is not a relevant coreceptor in the SIV/macaque model but may play a role in SIV replication and transmission in naturally infected sooty mangabeys. PMID:10799581

Pöhlmann, S; Lee, B; Meister, S; Krumbiegel, M; Leslie, G; Doms, R W; Kirchhoff, F

2000-06-01

168

Effect of Nox control technology on efficient utilization of fuel and energy  

Microsoft Academic Search

Combustion modification technology has enabled many utility boilers to meet the NOx emission standards. Since the technology involves modifications in either the combustion or the operating conditions, it is expected to have some effect on the performance of the plant or boiler. This paper, therefore, outlines some of the important NOx control techniques and their influence on plant performance, thermal

M. R. Khan; O. I. Ogunsola

1983-01-01

169

DIFFERENCES IN FEED EFFICIENCY AND NUTRIENT UTILIZATION BETWEEN AND WITHIN CHANNEL CATFISH STRAINS AND FAMILIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Improving channel catfish growth and feed utilization are two important goals of selective breeding programs. The newest channel catfish strain (NWAC103) to be introduced to the United States catfish industry was selected for increased growth rate. Researchers and farmers alike attribute the 10-20% ...

170

Jicarilla Apache Utility Authority Renewable Energy and Energy Efficiency Strategic Planning  

SciTech Connect

The purpose of this Strategic Plan Report is to provide an introduction and in-depth analysis of the issues and opportunities, resources, and technologies of energy efficiency and renewable energy that have potential beneficial application for the people of the Jicarilla Apache Nation and surrounding communities. The Report seeks to draw on the best available information that existed at the time of writing, and where necessary, draws on new research to assess this potential. This study provides a strategic assessment of opportunities for maximizing the potential for electrical energy efficiency and renewable energy development by the Jicarilla Apache Nation. The report analyzes electricity use on the Jicarilla Apache Reservation in buildings. The report also assesses particular resources and technologies in detail, including energy efficiency, solar, wind, geothermal, biomass, and small hydropower. The closing sections set out the elements of a multi-year, multi-phase strategy for development of resources to the maximum benefit of the Nation.

Rabago, K.R.

2008-06-28

171

Analysis of power sector efficiency improvements for an integrated utility planning process in Costa Rica  

SciTech Connect

In an effort to analyze and document the potential for power sector efficiency improvements from generation to end-use, the Agency for International Development and the Government of Costa Rica are jointly conducting an integrated power sector efficiency analysis. Potential for energy and cost savings in power plants, transmission and distribution, and demand-side management programs are being evaluated. The product of this study will be an integrated investment plan for the Instituto Costarricense de Electricidad, incorporating both supply and demand side investment options. This paper presents the methodology employed in the study, as well as preliminary estimates of the results of the study. 14 refs., 4 figs., 5 tabs.

Waddle, D.B.; MacDonald, J.M.

1990-01-01

172

Highly atom efficient catalytic reactions utilizing water and alcohols as reagents  

Microsoft Academic Search

In this accounts, we describe our recent studies on hydrolysis, alcoholysis, and addition of alcohols to organic molecules. The reactions utilizing water and alcohols as a reagent are one of the most basic and simple reactions. The palladium-catalyzed asymmetric hydrolysis and alcoholysis of vinyl ethers gave valuable axially chiral 1,1?-bi-2-naphthol and 1,1?-bi-2-phenol derivatives and chiral P-chirogenic compounds in optically active

Akiyuki Hamasaki; Eiji Yamamoto; Hisashi Itoh; Makoto Tokunaga

2011-01-01

173

A NETWORK COMMON DATA FORM (NETCDF) UTILITY FOR EFFICIENT ENVIRONMENTAL DATA PROCESSING AND VISUALIZATION  

Microsoft Academic Search

NetCDF is a data sharing protocol and library that is commonly used in large-scale atmospheric and environmental data archiving and modelling. Most current NetCDF- related utilities are for Unix and Linux platforms while only a few, mostly commercial, are for the Microsoft Windows platform. The NetCDF tool described here was built as a standard executable as well as a COM

Jinxun Liu; Jing M. Chen; David T. Price; Shuguang Liu

2004-01-01

174

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

Microsoft Academic Search

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

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

2012-01-01

175

Efficiency of Nitrogen Fertilizer for Potato under Fertigation Utilizing a Nitrogen Tracer Technique  

Microsoft Academic Search

Efficient crop use of nitrogen (N) fertilizer is critical from economic and environmental viewpoints, especially under irrigated conditions. Nitrogen fertilizer (N?labeled urea) and irrigation methods (drip and furrow) were evaluated on spring and fall potato cultivars under Syrian Mediterranean climatic conditions. Field experiments were conducted in the El?Ghab Valley near Hama in fall 2000 and spring 2001 on a heavy

Mussaddak Janat

2007-01-01

176

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...

177

Energy efficient process for recycling sodium sulfate utilizing ceramic solid electrolyte. Final report.  

National Technical Information Service (NTIS)

A major development effort was undertaken at Cerarnatec to increase the sodium transport rates and transport efficiency of NaSICON membranes for recycling sodium sulfate. A novel NaSICON composition (NAS-D) and its doped versions were developed that exhib...

1999-01-01

178

Enhancement of Research and Development Output Utilization Efficiencies; Linker Concept Methodology in the Technology Transfer Process.  

ERIC Educational Resources Information Center

This study investigated the hypothesis that there is a relationship between the output efficiency of research and development and the behavioral characteristics of individuals in the user organization. Through a review of the literature, a number of concepts and models that tend to support the hypothesis are discussed. The authors then present a…

Creighton, J. W.; And Others

179

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...

180

Physically based volumetric efficiency model for diesel engines utilizing variable intake valve actuation  

Microsoft Academic Search

Advanced diesel engine architectures employing flexible valve trains enable emissions reductions and fuel economy improvements. Flexibility in the valve train allows engine designers to optimize the gas exchange process in a manner similar to how common rail fuel injection systems enable optimization of the fuel injection process. Modulating valve timings directly impacts the volumetric efficiency of the engine since it

L Kocher; E Koeberlein; D G Van Alstine; K Stricker; G Shaver

2012-01-01

181

Utility-function-driven energy-efficient cooling in data centers  

Microsoft Academic Search

The sharp rise in energy usage in data centers, fueled by increased IT workload and high server density, and coupled with a concomitant increase in the cost and volatility of the energy supply, have triggered urgent calls to improve data center energy efficiency. In response, researchers have developed energy-aware IT systems that slow or shut down servers without sacrificing performance

Rajarshi Das; Jeffrey O. Kephart; Jonathan Lenchner; Hendrik Hamann

2010-01-01

182

Photosystem trap energies and spectrally-dependent energy-storage efficiencies in the Chl d-utilizing cyanobacterium, Acaryochloris marina.  

PubMed

Acaryochloris marina is the only species known to utilize chlorophyll (Chl) d as a principal photopigment. The peak absorption wavelength of Chl d is redshifted ?40nm in vivo relative to Chl a, enabling this cyanobacterium to perform oxygenic phototrophy in niche environments enhanced in far-red light. We present measurements of the in vivo energy-storage (E-S) efficiency of photosynthesis in A. marina, obtained using pulsed photoacoustics (PA) over a 90-nm range of excitation wavelengths in the red and far-red. Together with modeling results, these measurements provide the first direct observation of the trap energies of PSI and PSII, and also the photosystem-specific contributions to the total E-S efficiency. We find the maximum observed efficiency in A. marina (40±1% at 735nm) is higher than in the Chl a cyanobacterium Synechococcus leopoliensis (35±1% at 690nm). The efficiency at peak absorption wavelength is also higher in A. marina (36±1% at 710nm vs. 31±1% at 670nm). In both species, the trap efficiencies are ?40% (PSI) and ?30% (PSII). The PSI trap in A. marina is found to lie at 740±5nm, in agreement with the value inferred from spectroscopic methods. The best fit of the model to the PA data identifies the PSII trap at 723±3nm, supporting the view that the primary electron-donor is Chl d, probably at the accessory (Chl(D1)) site. A decrease in efficiency beyond the trap wavelength, consistent with uphill energy transfer, is clearly observed and fit by the model. These results demonstrate that the E-S efficiency in A. marina is not thermodynamically limited, suggesting that oxygenic photosynthesis is viable in even redder light environments. PMID:23159726

Mielke, Steven P; Kiang, Nancy Y; Blankenship, Robert E; Mauzerall, David

2012-11-15

183

Development of a highly efficient brushless dc motor utilizing both radial and axial air gaps  

NASA Astrophysics Data System (ADS)

This research proposes an effective structure for a brushless dc motor utilizing both radial and axial air gaps. The proposed motor generates torque in both the radial and axial air gaps, while the conventional motor generates torque only in the radial air gap. The proposed motor was optimized to minimize the electromagnetic loss of the motor to increase the effective air gap length and fill-factor of the coil while decreasing the saturation of the core at the same time. The electromagnetic loss was reduced by 35% in comparison with a conventional motor.

Kang, K. J.; Jang, G. H.; Sung, S. J.; Chang, J. H.

2012-04-01

184

Thermochemical characterization of pigeon pea stalk for its efficient utilization as an energy source  

SciTech Connect

Pigeon pea stalk is a widely available biomass species in India. In this article the potential use of pigeon pea stalk as a fuel source through thermochemical conversion methods such as combustion, gasification, and pyrolysis has been investigated through experimentation using a thermogravimetric analyzer and pilot-plant-scale equipment. It has been proposed that pigeon pea stalks can be effectively utilized in two ways. The first is to pyrolyze the material to produce value-added products such as char, tar, and fuel gas. The second alternative is to partially pyrolyze the material to remove tar-forming volatiles, followed by gasification of reactive char to generate producer gas.

Katyal, S.K.; Iyer, P.V.R.

2000-05-01

185

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

SciTech Connect

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.

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

1995-09-01

186

Increased efficiency of rf-induced evaporative cooling by utilizing gravity  

SciTech Connect

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.

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

2010-04-15

187

Langerhans cells utilize CD1a and langerin to efficiently present nonpeptide antigens to T cells  

PubMed Central

Langerhans cells (LCs) constitute a subset of DCs that initiate immune responses in skin. Using leprosy as a model, we investigated whether expression of CD1a and langerin, an LC-specific C-type lectin, imparts a specific functional role to LCs. LC-like DCs and freshly isolated epidermal LCs presented nonpeptide antigens of Mycobacterium leprae to T cell clones derived from a leprosy patient in a CD1a-restricted and langerin-dependent manner. LC-like DCs were more efficient at CD1a-restricted antigen presentation than monocyte-derived DCs. LCs in leprosy lesions coexpress CD1a and langerin, placing LCs in position to efficiently present a subset of antigens to T cells as part of the host response to human infectious disease.

Hunger, Robert E.; Sieling, Peter A.; Ochoa, Maria Teresa; Sugaya, Makoto; Burdick, Anne E.; Rea, Thomas H.; Brennan, Patrick J.; Belisle, John T.; Blauvelt, Andrew; Porcelli, Steven A.; Modlin, Robert L.

2004-01-01

188

Fast rotation invariant 3D feature computation utilizing efficient local neighborhood operators.  

PubMed

We present a method for densely computing local rotation invariant image descriptors in volumetric images. The descriptors are based on a transformation to the harmonic domain, which we compute very efficiently via differential operators. We show that this fast voxelwise computation is restricted to a family of basis functions that have certain differential relationships. Building upon this finding, we propose local descriptors based on the Gaussian Laguerre and spherical Gabor basis functions and show how the coefficients can be computed efficiently by recursive differentiation. We exemplarily demonstrate the effectiveness of such dense descriptors in a detection and classification task on biological 3D images. In a direct comparison to existing volumetric features, among them 3D SIFT, our descriptors reveal superior performance. PMID:22201055

Skibbe, Henrik; Reisert, Marco; Schmidt, Thorsten; Brox, Thomas; Ronneberger, Olaf; Burkhardt, Hans

2012-08-01

189

Process Improvement Methods Increase the Efficiency, Accuracy and Utility of a Neurocritical Care Research Repository  

PubMed Central

Background Reliable and efficient data repositories are essential for the advancement of research in Neurocritical care. Various factors, such as the large volume of patients treated within the Neuro ICU, their differing length and complexity of hospital stay and the substantial amount of desired information can complicate the process of data collection. Methods We adapted the tools of process improvement to the data collection and database design of a research repository for a Neuroscience intensive care unit. Using the Shewhart-Deming method, we implemented an iterative approach to improve the process of data collection for each element. After an initial design phase, we re-evaluated all data fields that were challenging or time-consuming to collect. We then applied root-cause analysis to optimize the accuracy and ease of collection, and to determine the most efficient manner of collecting the maximal amount of data. Results During a six month period, we iteratively analyzed the process of data collection for various data elements. For example, the pre-admission medications were found to contain numerous inaccuracies after comparison with a gold standard (sensitivity 71% and specificity 94%). Also, our first method of tracking patient admissions and discharges contained higher than expected errors (sensitivity 94% and specificity 93%). In addition to increasing accuracy, we focused on improving efficiency. Through repeated incremental improvements, we reduced the number of subject records that required daily monitoring from 40 to 6 per day, and decreased daily effort from 4.5 to 1.5 hours per day. Conclusions By applying process improvement methods to the design of a Neuroscience ICU data repository, we achieved a three-fold improvement in efficiency and increased accuracy. Although individual barriers to data collection will vary from institution to institution, a focus on process improvement is critical to overcoming these barriers.

O'Connor, Sydney; Ayres, Alison; Cortellini, Lynelle; Rosand, Jonathan; Rosenthal, Eric; Kimberly, W. Taylor

2012-01-01

190

Sugar transporters in efficient utilization of mixed sugar substrates: current knowledge and outlook  

Microsoft Academic Search

There is increasing interest in production of transportation fuels and commodity chemicals from lignocellulosic biomass, most\\u000a desirably through biological fermentation. Considerable effort has been expended to develop efficient biocatalysts that convert\\u000a sugars derived from lignocellulose directly to value-added products. Glucose, the building block of cellulose, is the most\\u000a suitable fermentation substrate for industrial microorganisms such as Escherichia coli, Corynebacterium glutamicum,

Toru Jojima; Crispinus A. Omumasaba; Masayuki Inui; Hideaki Yukawa

2010-01-01

191

Efficient utilization of short rotation tree biomass for cooking in India  

NASA Astrophysics Data System (ADS)

The human as well as livestock population increase is phenomenal in developing world including India. The survival of this huge population certainly depends on the carrying capacity of the natural systems, which is essentially determined by the nature itself. Present state of the forests can satisfy the needs of certain population and the demand for wood has rapidly outstripped the sustainability of forests. The fuelwood requirements in the developing world is approximately 80 per cent of total wood requirements and is the major cause of forest degradation. Therefore, there is need to maximize the productivity on one hand and protection/extention of the area on another hand. Wood substitution is an option including shifting from fuelwood for cooking to fossil fuels but in the changing climatic situation, this option is short term alternative. There is need to produce more and use the same efficiently to reduce the demands. Millions of households across the country are using crude cooking stoves for their daily needs which are not only energy inefficient but detrimental to women health also. It has been the policy of Government to encourage trees outside forests to minimize the pressure from forests through meeting requirements outside forests, which is possible through intensively managed short rotation forestry and also some initiatives have been taken to increase the fuelwood efficiency through improved cooking stove, which are working successfully. Woodfuel remained the most important source of household energy in India but regular attempts have not been made to improve the efficiency in its use. This paper will focus on potential of short rotation forestry plantations for energy consumption and its efficient use at domestic scale. This has three fold interrelated economic, environmental and social impact. Key words: Short Rotation Forestry, trees outside forests, wood energy, cooking stove

Sharma, R.; Chauhan, S. K.

2012-04-01

192

High efficient treatment of citric acid effluent by Chlorella vulgaris and potential biomass utilization.  

PubMed

The efficiency of treating citric acid effluent by green algae Chlorella was investigated. With the highest growth rate, Chlorella vulgaris C9-JN2010 that could efficiently remove nutrients in the citric acid effluent was selected for scale-up batch experiments under the optimal conditions, where its maximum biomass was 1.04 g l(-1) and removal efficiencies of nutrients (nitrogen, phosphorus, total organic carbon, chemical oxygen demand and biochemical oxygen demand) were above 90.0%. Algal lipid and protein contents were around 340.0 and 500.0 mg · g(-1) of the harvested biomass, respectively. Proportions of polyunsaturated fatty acids in the lipids and eight kinds of essential amino acids in algal protein were 74.0% and 40.0%, respectively. Three major fatty acids were hexadecanoic acid, eicosapentaenoic acid and docosadienoic acid. This specific effluent treatment process could be proposed as a dual-beneficial approach, which converts nutrients in the high strength citric acid effluent into profitable byproducts and reduces the contaminations. PMID:23131649

Li, Changling; Yang, Hailin; Xia, Xiaole; Li, Yuji; Chen, Luping; Zhang, Meng; Zhang, Ling; Wang, Wu

2012-08-31

193

Improving derivatization efficiency of BMAA utilizing AccQ-Tag in a complex cyanobacterial matrix.  

PubMed

Two different assays have been developed and used in order to investigate the optimal conditions for derivatization and detection of acid beta-N-methyl-amino-L-alanine (BMAA) in a cyanobacterial sample. BMAA was extracted from cyanobacterial cultures both from the cytosolic ("free") fraction and in the precipitated ("protein") fraction using a newly developed extraction scheme and the sample matrix was standardized according to protein concentration to ensure the highest possible derivative yield. A rapid and sensitive HPLC method for fluorescence detection of the non-protein amino acid BMAA in cyanobacteria, utilizing the Waters AccQ-Tag chemistry and Chromolith Performance RP-18e columns was developed. Using this new method and utilizing a different buffer system and column than that recommended by Waters, we decreased the time between injections by 75%. The limit of quantification was determined to be 12 nmol and limit of detection as 120 fmol. The linear range was in the range of 8.5 nmol-84 pmol. Accuracy and precision were well within FDA guidelines for bioanalysis. PMID:18188663

Eriksson, Johan; Jonasson, Sara; Papaefthimiou, Dimitra; Rasmussen, Ulla; Bergman, Birgitta

2008-01-09

194

Highly efficient polarized polymer light-emitting diodes utilizing oriented films of ?-phase poly(9,9-dioctylfluorene)  

NASA Astrophysics Data System (ADS)

Uniaxially oriented films of ?-phase poly(9,9-dioctylfluorene) (PFO) were realized by a friction-transfer technique followed by thermal annealing and vapor treatments. Absorption and photoluminescence (PL) spectra show the characteristics of ?-phase: an additional absorption peak at 433 nm and redshifted PL peaks compared with those of the usual nematic (N) phase. We fabricated polarized polymer light-emitting diodes utilizing oriented films of ?-phase PFO. Highly polarized ?-phase emission with an integrated polarization ratio of 51 was observed from the devices. The efficiency of the devices based on ?-phase reached 2.0 cd/A, which is two times higher than that based on N-phase.

Misaki, Masahiro; Chikamatsu, Masayuki; Yoshida, Yuji; Azumi, Reiko; Tanigaki, Nobutaka; Yase, Kiyoshi; Nagamatsu, Shuichi; Ueda, Yasukiyo

2008-07-01

195

Effects of dietary protein levels on growth, feed utilization, protein retention efficiency and body composition of young Heteropneustes fossilis (Bloch)  

Microsoft Academic Search

An 8-week growth trial was conducted to assess the effect of dietary protein on growth, feed utilization, protein retention\\u000a efficiency, and body composition of young Heteropneustes fossilis (10.02 ± 0.09 g; 9.93 ± 0.07 cm). Isocaloric (4.15 kcal g?1, GE) diets with varying levels of protein (25, 30, 35, 40, 45, and 50% of the diet) were fed near to satiation to triplicate\\u000a groups of fish. Optimum dietary

Tabassum Qamar Siddiqui; Mukhtar A. Khan

2009-01-01

196

Highly efficient pure yellow electrophosphorescent device by utilizing an electron blocking material  

Microsoft Academic Search

Yellow organic light-emitting devices (OLEDs) are not easy to obtain since yellow emissive materials are rare and the color purity is often perturbed by the emission from the carrier transport layer. A high-efficiency yellow-emission phosphorescent complex, iridium(III) bis(2-(9,9'-spirobi[fluorene]-7-yl)pyridine-N,C2') acetylacetonate ((SBFP)2Ir(acac)), is selected as the dopant material for yellow phosphorescent OLEDs (PHOLEDs). An electron blocking material, Ir(ppz)3 (ppz = phenylpyrazole), is

Teng Fei; Chunlei Wang; Shanfeng Xue; Xin Gu; Feng Li; Yuguang Ma

2009-01-01

197

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

SciTech Connect

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.

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

2001-11-05

198

Elementary school utilizes solar design techniques and groundwater cooling system for energy efficiency  

SciTech Connect

Florence Wilson Elementary School was designed with low energy consumption as one of its highest priorities. Long-term ownership of this facility by the Unified School District (USD) 457 provided the direction to explore and incorporate many energy conserving techniques in the design of the structure, and the mechanical and electrical systems. Early design schematics emphasized architectural consideration for solar utilization from both active and passive means. The 36,180 ft{sup 2} (3,361 m{sup 2}) elementary school was constructed in 1981. In 1983, a two-classroom addition increased the school`s size to 37,907 ft{sup 2} (3,522 m{sup 2}). This project was such a success that when the need arose for two additional schools, the original architectural, mechanical and electrical design team was called upon to prepare bid documents using Florence Wilson as a prototype design worthy of repetition.

Norton, D.I. [Professional Engineering Consultants, Wichita, KS (United States)

1995-03-01

199

COGNITIVE RADIOS FOR DYNAMIC SPECTRUM ACCESS - Dynamic Frequency Hopping Communities for Efficient IEEE 802.22 Operation  

Microsoft Academic Search

One of the key challenges of the emerging cognitive radio-based IEEE 802.22 wireless regional area networks (WRANs) is to address two apparently conflicting requirements: ensuring QoS satisfaction for WRAN services while providing reliable spectrum sensing for guaranteeing licensed user protection. To perform reliable sensing, in the basic operation mode on a single frequency band (non-hopping mode), one must allocate quiet

Wendong Hu; Daniel Willkomm; Murad Abusubaih; James Gross; George Vlantis; Mario Gerla; Adam Wolisz

2007-01-01

200

Efficiency of CCR5 Coreceptor Utilization by the HIV Quasispecies Increases over Time, But Is Not Associated with Disease Progression  

PubMed Central

Abstract CCR5 is the primary coreceptor for HIV entry. Early after infection, the HIV viral population diversifies rapidly into a quasispecies. It is not known whether the initial efficiency of the viral quasispecies to utilize CCR5 is associated with HIV disease progression or if it changes in an infected individual over time. The CCR5 and CXCR4 utilization efficiencies (R5-UE and X4-UE) of the HIV quasispecies were examined using a pseudovirus, single-round infection assay for samples obtained from known seroconverters from Rakai district, Uganda (n=88). Initial and longitudinal R5-UE values were examined to assess the association of R5-UE with HIV disease progression using multivariate Cox proportional hazard models. Longitudinal samples were analyzed for 35 seroconverters who had samples available from multiple time points. There was no association between initial or longitudinal changes in R5-UE and the hazard of HIV disease progression (p=0.225 and p=0.942, respectively). In addition, R5-UE increased significantly over time after HIV seroconversion (p<0.001), regardless of HIV subtype or the emergence of CXCR4-tropic virus. These data demonstrate that the R5-UE of the viral quasispecies early in HIV infection is not associated with disease progression, and that R5-UE levels increase in HIV-infected individuals over time.

Redd, Andrew D.; Laeyendecker, Oliver; Kong, Xiangrong; Kiwanuka, Noah; Lutalo, Tom; Huang, Wei; Gray, Ronald H.; Wawer, Maria J.; Serwadda, David; Eshleman, Susan H.

2012-01-01

201

Low-cost, high-efficiency solar cells utilizing GaAs-on-Si technology  

SciTech Connect

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.

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

1993-04-01

202

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

SciTech Connect

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.

None

2012-02-23

203

Area utilization efficiency of a sloping heliostate system for solar concentration  

SciTech Connect

Area utlization efficiency (AUE) is formulated for a sloping heliostat system facing any direction. The effects of slope shaping, incidence factor, sun shading, and tower blocking by the mirrors are all taken into account. Our results show that annually averaged AUEs calculated for heliostat systems (1) increase with tower height at low slope angles but less rapidly at high slopes, (2) increase monotonically with slope angle and saturate at large slopes for systems facing due south, (3) reach a maximum at a certain slope for systems facing other directions than due south, and (4) drop sharply at slopes greater than a certain value for systems facing due east or west due to slope shading effect. The results are useful for solar energy collection on non-flat terrains.

Wei, L.Y.

1983-02-15

204

Tricaproin, tricaprin and trilaurin are utilized more efficiently than tricaprylin by carp (Cyprinus carpio L.) larvae.  

PubMed

We investigated the effect of chain length of dietary medium-chain fatty acids (MCFA) on growth performance and fatty acid composition of first-feeding carp larvae. In a first trial, five semi-purified isolipidic (23-24 g/100 g of dry matter) diets were formulated to contain either 10 g/100 g triolein (control diet) or 5 g/100 g triolein and 5 g/100 g medium-chain triacylglycerols (MCT) supplied as tricaproin, tricaprylin, tricaprin or trilaurin. After 21 d, survival and growth rates were significantly greater in larvae fed diets containing triolein, tricaproin, tricaprin and trilaurin (final survival: 92 +/- 7% and mean larval weight: 42 +/- 15 mg) than in larvae fed tricaprylin (final survival: 56 +/- 12% and mean larval weight: 15 +/- 1 mg). The recovered levels of the fed MCFA in larval total lipids were respectively 0, 1.3, 7.3 and 8.1 g/100 g of total fatty acids. In a second trial, two isolipidic (18 g/100 g) diets containing 10 g/100 g triolein or tricaprylin were tested. High amounts of capric acid (up to 25 g/100 g of total fatty acids) were found in neutral lipids of carp larvae fed tricaprylin for 11 d, suggesting an unusual elongation of caprylic acid. This study underlines the peculiarity of tricaprylin among other MCT which seem well utilized up to 20-30 g/100 g of total dietary fatty acids. The exception of tricaprylin raises the question of the metabolic pathways followed by this MCT, especially for the suggested direct elongation of caprylic acid into capric acid. PMID:10917917

Fontagné, S; Corraze, G; Bergot, P

2000-08-01

205

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

SciTech Connect

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.

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

2011-09-30

206

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

SciTech Connect

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.

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

2009-01-01

207

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

PubMed

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

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

2009-11-04

208

Efficient 2,3-Butanediol Production from Cassava Powder by a Crop-Biomass-Utilizer, Enterobacter cloacae subsp. dissolvens SDM  

PubMed Central

Background 2,3-Butanediol (BD) is considered as one of the key platform chemicals used in a variety of industrial applications. It is crucial to find an efficient sugar-utilizing strain and feasible carbon source for the economical production of BD. Methodology/Principal Findings Efficient BD production by a newly isolated Enterobacter cloacae subsp. dissolvens SDM was studied using crop-biomass cassava powder as substrate. The culture conditions and fermentation medium for BD production were optimized. Under the optimal conditions, 78.3 g l?1 of BD was produced after 24 h in simultaneous saccharification and fermentation (SSF), with a yield of 0.42 g BD g?1 cassava powder and a specific productivity of 3.3 g l?1 h?1. A higher BD concentration (93.9 g l?1) was produced after 47 h in fed-batch SSF. Conclusions/Significance The results suggest that strain SDM is a good candidate for the BD production, and cassava powder could be used as an alternative substrate for the efficient production of BD.

Ma, Cuiqing; Gao, Chao; Li, Lixiang; Wang, Yu; Tao, Fei; Xu, Ping

2012-01-01

209

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

NASA Astrophysics Data System (ADS)

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.

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

2013-01-01

210

Efficient utilization of rare variants for detection of disease-related genomic regions.  

PubMed

When testing association between rare variants and diseases, an efficient analytical approach involves considering a set of variants in a genomic region as the unit of analysis. One factor complicating this approach is that the vast majority of rare variants in practical applications are believed to represent background neutral variation. As a result, analyzing a single set with all variants may not represent a powerful approach. Here, we propose two alternative strategies. In the first, we analyze the subsets of rare variants exhaustively. In the second, we categorize variants selectively into two subsets: one in which variants are overrepresented in cases, and the other in which variants are overrepresented in controls. When the proportion of neutral variants is moderate to large we show, by simulations, that the both proposed strategies improve the statistical power over methods analyzing a single set with total variants. When applied to a real sequencing association study, the proposed methods consistently produce smaller p-values than their competitors. When applied to another real sequencing dataset to study the difference of rare allele distributions between ethnic populations, the proposed methods detect the overrepresentation of variants between the CHB (Chinese Han in Beijing) and YRI (Yoruba people of Ibadan) populations with small p-values. Additional analyses suggest that there is no difference between the CHB and CHD (Chinese Han in Denver) datasets, as expected. Finally, when applied to the CHB and JPT (Japanese people in Tokyo) populations, existing methods fail to detect any difference, while it is detected by the proposed methods in several regions. PMID:21170328

Zhang, Lei; Pei, Yu-Fang; Li, Jian; Papasian, Christopher J; Deng, Hong-Wen

2010-12-10

211

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

PubMed

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-m(3) 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

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

2013-06-19

212

Limits of Efficiency of Solar Cells under Amo-Spectrum Illumination: Comparison Between Si and GaAs Cells.  

National Technical Information Service (NTIS)

Research on the efficiency limits of GaAs and Si solar cells is described. Radiative and Auger recombination losses are taken into consideration in the calculations. An assessment of the benefits to be expected from applying techniques to concentrate the ...

G. L. Araujo A. Marti

1989-01-01

213

Premature stop codons involved in muscular dystrophies show a broad spectrum of readthrough efficiencies in response to gentamicin treatment  

Microsoft Academic Search

The suppression levels induced by gentamicin on premature stop codons, caused by primary nonsense mutations found in muscular dystrophy patients, were assessed using a very sensitive dual reporter gene assay. Results show that: (i) the effect of gentamicin on readthrough is similar in cultured cells and in vivo in murine skeletal muscle; (ii) a wide variability of readthrough efficiency is

L Bidou; I Hatin; N Perez; V Allamand; J-J Panthier; J-P Rousset

2004-01-01

214

Efficient lasing of a TEA CO/sub 2/ laser with ultraviolet preionization and utilizing unconventional transitions  

SciTech Connect

The results are given of an investigation of the conditions for efficient lasing, utilizing unconventional transitions in TEA CO/sub 2/ lasers. The following bands were considered: 00/sup 0/2--(10/sup 0/1, 02/sup 0/1)/sub i/,II (lambda = 9.2--10.8 ..mu..); (10/sup 0/1, 02/sup 0/1)/sub i/,II--(10/sup 0/0, 02/sup 0/0)/sub i/,II (lambda = 4.3 ..mu..); 01/sup 1/1--(11/sup 1/0, 03/sup 1/0)/sub i/ (lambda = 10.8--11.4 ..mu..). In the case of the 01/sup 1/1--(11/sup 1/0, 03/sup 1/0)/sub i/ and 00/sup 0/2--(10/sup 0/1, 02/sup 0/0)/sub i/,II transitions, a lasing efficiency of 35--52% of that for the regular band was obtained experimentally. The results are given of investigations of lasing in the wavelength range 11.45--11.85 ..mu.. (01/sup 1/1--(11/sup 1/0, 03/sup 1/0)/sub i/ band) using the isotopically substituted molecules /sup 13/CO/sub 2/.

Stepanov, B.I.; Churakov, V.V.

1982-12-01

215

Utilization of non-AUG initiation codons in a flow cytometric method for efficient selection of recombinant cell lines.  

PubMed

Here we describe a method that couples flow cytometric detection with the attenuated translation of a reporter protein to enable efficient selection of CHO clones producing high levels of recombinant proteins. In this system, a small cell surface reporter protein is expressed from an upstream open reading frame utilizing a non-AUG initiation (alternate start) codon. Due to the low translation initiation efficiency of this alternate start codon, the majority of translation initiation events occur at the first AUG of the downstream open reading frame encoding the recombinant protein of interest. While translation of the reporter is significantly reduced, the levels are sufficient for detection using flow cytometric methods and, in turn, predictive of protein expression from the gene of interest since both ORFs are translated from the same mRNA. Using this system, CHO cells have been sorted to obtain enriched pools producing significantly higher levels of recombinant proteins than the starting cell population and clones with significantly better productivity than those generated from limiting dilution cloning. This method also serves as an effective screening tool during clone expansion to enable resources to be focused solely on clones with both high and stable expression. PMID:21618473

Cairns, Victor R; DeMaria, Christine T; Poulin, Francis; Sancho, José; Liu, Ping; Zhang, Jin; Campos-Rivera, Juanita; Karey, Kenneth P; Estes, Scott

2011-06-16

216

Phosphate utilization efficiency correlates with expression of low-affinity phosphate transporters and noncoding RNA, IPS1, in barley.  

PubMed

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

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

2011-05-23

217

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

NASA Astrophysics Data System (ADS)

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.

Trofimov, Vyacheslav A.; Varentsova, Svetlana A.

2009-05-01

218

High Prescription Drug Utilization and Associated Costs among Medicaid-eligible Children with Autism Spectrum Disorders Identified by a Population-based Surveillance Network  

Microsoft Academic Search

PurposeThis study assessed medication use and associated costs among 8- and 15-year-old children with autism spectrum disorders (ASD) identified by the South Carolina Autism and Developmental Disabilities Monitoring (SCADDM) Network.

Sarah L. Logan; Joyce S. Nicholas; Laura A. Carpenter; Lydia B. King; Elizabeth Garrett-Mayer; Jane M. Charles

219

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

PubMed

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

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

2012-06-06

220

Reflection hologram solar spectrum-splitting filters  

NASA Astrophysics Data System (ADS)

In this paper we investigate the use of holographic filters in solar spectrum splitting applications. Photovoltaic (PV) systems utilizing spectrum splitting have higher theoretical conversion efficiency than single bandgap cell modules. Dichroic band-rejection filters have been used for spectrum splitting applications with some success however these filters are limited to spectral control at fixed reflection angles. Reflection holographic filters are fabricated by recording interference pattern of two coherent beams at arbitrary construction angles. This feature can be used to control the angles over which spectral selectivity is obtained. In addition focusing wavefronts can also be used to increase functionality in the filter. Holograms fabricated in dichromated gelatin (DCG) have the benefit of light weight, low scattering and absorption losses. In addition, reflection holograms recorded in the Lippmann configuration have been shown to produce strong chirping as a result of wet processing. Chirping broadens the filter rejection bandwidth both spectrally and angularly. It can be tuned to achieve spectral bandwidth suitable for spectrum splitting applications. We explore different DCG film fabrication and processing parameters to improve the optical performance of the filter. The diffraction efficiency bandwidth and scattering losses are optimized by changing the exposure energy, isopropanol dehydration bath temperature and hardening bath duration. A holographic spectrum-splitting PV module is proposed with Gallium Arsenide (GaAs) and silicon (Si) PV cells with efficiency of 25.1% and 19.7% respectively. The calculated conversion efficiency with a prototype hologram is 27.94% which is 93.94% compared to the ideal spectrum-splitting efficiency of 29.74%.

Zhang, Deming; Gordon, Michael; Russo, Juan M.; Vorndran, Shelby; Escarra, Matthew; Atwater, Harry; Kostuk, Raymond K.

221

Group-based spectrum assignment in dynamic flex-grid optical networks  

NASA Astrophysics Data System (ADS)

Traditional wavelength switched optical network employing wavelength-division-multiplexing (WDM) technology, allocates constant spectrum band to different kinds of services, which lacks flexibility in spectrum provisioning and thus reduces the resource utilization efficiency. Flex-grid technology, which introduces a finer spectrum granularity and allocates spectrum to different services flexibly according to their required bandwidth, is considered a promising candidate solution to improve the resource utilization efficiency of an optical network. However, since multiple contiguous spectrum granularities are usually assigned to a single service in such flex-grid optical network, the spectrum continuity and contiguity constraints should always be guaranteed, which may induce spectrum fragmentation. With the accumulation of spectrum fragmentation, available spectrum resources decrease, and this will greatly worsen the performance of the whole network, especially in networking. Therefore, spectrum fragmentation is considered a serious problem in flex-grid optical networks and many schemes have been proposed to solve it. These existing schemes, known as defragmentation, can reduce spectrum fragmentation either by rerouting the lightpath or by reallocating the spectrum for a service, which re-optimizes the spectrum resources. However, in the rerouting or reallocation procedure, existing traffic may be disrupted or extra resources, such as alternative spectrum or expensive spectrum convertors, are needed. None of these schemes can solve spectrum fragmentation with both no disrupted traffic and extra resources. It is because all these schemes utilize remedial methods to solve fragmentation problem and either disrupted traffic or extra resources are the cost when they cope with the defragmented spectrum. Different from all the above schemes, we propose a precautionary method to solve fragmentation problem in this paper. By introducing group-based spectrum assignment algorithm into flex-grid optical networks, spectrum resources are sorted into groups and each spectrum group only accommodates one specific kind of services. Since released spectrum can always be reused by the services of the same kind, spectrum fragmentation is prevented from its generation. Simulation results demonstrate that the proposed algorithm induces no spectrum fragmentations and is suitable to accommodate high-speed services.

Qiu, Yang

2013-10-01

222

Telecommunications: Strong Support for Extending FCC's Auction Authority Exists, But Little Agreement on Other Options to Improve Efficient Use of Spectrum.  

National Technical Information Service (NTIS)

The current spectrum allocation process is largely characterized as a 'command-and-control' process, in which the government largely dictates how the spectrum is used. Many stakeholders we spoke with, along with panelists on our expert panel, identified a...

2005-01-01

223

Partial GSM spectrum reuse for femtocells  

Microsoft Academic Search

In this paper the feasibility of femtocells partially reusing GSM spectrum is investigated. Due to the increasing scarcity and cost of spectrum, partial spectrum reuse by secondary networks is being considered to improve spectral efficiency. Additionally, new revenue streams can be extracted from existing resources by utilising partial spectrum reuse. The partial reuse of spectrum depends largely on the ability

Joseph O'Carroll; Holger Claussen; Linda Doyle

2009-01-01

224

COAL MINE METHANE EMISSIONS REDUCTION PROJECTS IN KUZBASS: SELECTION OF METHANE UTILIZATION OPTIONS, ECONOMICAL EFFICIENCY ASSESSMENTS AND FINANCE SOURCES  

Microsoft Academic Search

Coal mine methane resources of Kuznetsk coal basin in Russia amounts to over 13 trillion cubic meters. Presently 47 coal mines operate in the region and emit 216 million cubic meters of methane per year but unfortunately none of them attempt to utilize drained methane. Development of coal mine methane recovery and utilization is of great technological, economical and ecological

225

Development of Technologies for a High Efficiency, Very Low Emission, Diesel Engine for Light Trucks and Sport Utility Vehicles  

SciTech Connect

Cummins Inc., in partnership with the Department of Energy, has developed technology for a new highly efficient, very low emission, diesel engine for light trucks and sport utility vehicles. This work began in April 1997, and started with very aggressive goals for vehicles in the 5751 to 8500 pound GCW weight class. The primary program goals were as follows: (1) EMISSIONS NOx = 0.50 g/mi PM = 0.05 g/mi CO = 2.8 g/mi NMHC = 0.07 g/mi California decided to issue new and even tougher LEV II light truck regulations late in 1999. EPA also issued its lower Tier 2 regulations late in 2000. The net result was that the targets for this diesel engine project were lowered, and these goals were eventually modified by the publication of Federal Tier 2 emission standards early in 2000 to the following: NOx = 0.07 g/mi PM = 0.01 g/mi (2) FUEL ECONOMY The fuel economy goal was 50 percent MPG improvement (combined city/highway) over the 1997 gasoline powered light truck or sport utility vehicle in the vehicle class for which this diesel engine is being designed to replace. The goal for fuel economy remained at 50 percent MPG improvement, even with the emissions goal revisions. (3) COOPERATIVE DEVELOPMENT Regular design reviews of the engine program will be conducted with a vehicle manufacturer to insure that the concepts and design specifics are commercially feasible. (DaimlerChrysler has provided Cummins with this design review input.) Cummins has essentially completed a demonstration of proof-of-principle for a diesel engine platform using advanced combustion and fuel system technologies. Cummins reported very early progress in this project, evidence that new diesel engine technology had been developed that demonstrated the feasibility of the above emissions goals. Emissions levels of NOx = 0.4 g/mi and PM = 0.06 g/mi were demonstrated for a 5250 lb. test weight vehicle with passive aftertreatment only. These results were achieved using the full chassis dynamometer FTP-75 test procedure that allowed compliance with the Tier 2 Interim Bin 10 Standards and would apply to vehicles in MY2004 through MY2007 timeframe. In further technology development with active aftertreatment management, Cummins has been able to report that the emissions goals for the Tier 2 Bin 5 standards were met on an engine running the full FTP-75 test procedure. The fuel economy on the chassis tests was measured at over 59 percent MPG improvement over the gasoline engines that are offered in typical SUVs and light trucks. The above demonstration used only in-cylinder fueling for management of the aftertreatment system.

Stang, John H.

1997-12-01

226

Development of Technologies for a High Efficiency, Very Low Emission, Diesel Engine for Light Trucks and Sport Utility Vehicles  

SciTech Connect

Cummins Inc., in partnership with the Department of Energy, has developed technology for a new highly efficient, very low emission, diesel engine for light trucks and sport utility vehicles. This work began in April 1997, and started with very aggressive goals for vehicles in the 5751 to 8500 pound GCW weight class. The primary program goals were as follows: (1) EMISSIONS--NO{sub x} = 0.50 g/mi; PM = 0.05 g/mi; CO = 2.8 g/mi; and NMHC = 0.07 g/mi. California decided to issue new and even tougher LEV II light truck regulations late in 1999. EPA also issued its lower Tier 2 regulations late in 2000. The net result was that the targets for this diesel engine project were lowered, and these goals were eventually modified by the publication of Federal Tier 2 emission standards early in 2000 to the following: NO{sub x} = 0.07 g/mi; and PM = 0.01 g/mi. (2) FUEL ECONOMY--The fuel economy goal was 50 percent MPG improvement (combined city/highway) over the 1997 gasoline powered light truck or sport utility vehicle in the vehicle class for which this diesel engine is being designed to replace. The goal for fuel economy remained at 50 percent MPG improvement, even with the emissions goal revisions. (3) COOPERATIVE DEVELOPMENT--Regular design reviews of the engine program will be conducted with a vehicle manufacturer to insure that the concepts and design specifics are commercially feasible. (DaimlerChrysler has provided Cummins with this design review input.) Cummins has essentially completed a demonstration of proof-of-principle for a diesel engine platform using advanced combustion and fuel system technologies. Cummins reported very early progress in this project, evidence that new diesel engine technology had been developed that demonstrated the feasibility of the above emissions goals. Emissions levels of NOx = 0.4 g/mi and PM = 0.06 g/mi were demonstrated for a 5250 lb. test weight vehicle with passive aftertreatment only. These results were achieved using the full chassis dynamometer FTP-75 test procedure that allowed compliance with the Tier 2 Interim Bin 10 Standards and would apply to vehicles in MY2004 through MY2007 timeframe. In further technology development with active aftertreatment management, Cummins has been able to report that the emissions goals for the Tier 2 Bin 5 standards were met on an engine running the full FTP-75 test procedure. The fuel economy on the chassis tests was measured at over 59 percent MPG improvement over the gasoline engines that are offered in typical SUVs and light trucks. The above demonstration used only in-cylinder fueling for management of the aftertreatment system.

John H. Stang

2005-12-31

227

Development of Technologies for a High Efficiency, Very Low Emission, Diesel Engine for Light Trucks and Sport Utility Vehicles  

SciTech Connect

Cummins Inc., in partnership with the Department of Energy, has developed technology for a new highly efficient, very low emission, diesel engine for light trucks and sport utility vehicles. This work began in April 1997, and started with very aggressive goals for vehicles in the 5751 to 8500 pound GCW weight class. The primary program goals were as follows: (1) EMISSIONS -- NOx = 0.50 g/mi; PM = 0.05 g/mi; CO = 2.8 g/mi; and NMHC = 0.07 g/mi. California decided to issue new and even tougher LEV II light truck regulations late in 1999. EPA also issued its lower Tier 2 regulations late in 2000. The net result was that the targets for this diesel engine project were lowered, and these goals were eventually modified by the publication of Federal Tier 2 emission standards early in 2000 to the following: NOx = 0.07 g/mi; and PM = 0.01 g/mi. (2) FUEL ECONOMY -- The fuel economy goal was 50 percent MPG improvement (combined city/highway) over the 1997 gasoline powered light truck or sport utility vehicle in the vehicle class for which this diesel engine is being designed to replace. The goal for fuel economy remained at 50 percent MPG improvement, even with the emissions goal revisions. (3) COOPERATIVE DEVELOPMENT -- Regular design reviews of the engine program will be conducted with a vehicle manufacturer to insure that the concepts and design specifics are commercially feasible. (DaimlerChrysler has provided Cummins with this design review input.) Cummins has essentially completed a demonstration of proof-of-principle for a diesel engine platform using advanced combustion and fuel system technologies. Cummins reported very early progress in this project, evidence that new diesel engine technology had been developed that demonstrated the feasibility of the above emissions goals. Emissions levels of NOx = 0.4 g/mi and PM = 0.06 g/mi were demonstrated for a 5250 lb. test weight vehicle with passive aftertreatment only. These results were achieved using the full chassis dynamometer FTP-75 test procedure that allowed compliance with the Tier 2 Interim Bin 10 Standards and would apply to vehicles in MY2004 through MY2007 timeframe. In further technology development with active aftertreatment management, Cummins has been able to report that the emissions goals for the Tier 2 Bin 5 standards were met on an engine running the full FTP-75 test procedure. The fuel economy on the chassis tests was measured at over 59 percent MPG improvement over the gasoline engines that are offered in typical SUVs and light trucks. The above demonstration used only in-cylinder fueling for management of the aftertreatment system.

Stang, John H.

2005-12-19

228

Efficient \\  

Microsoft Academic Search

In 1999, Poupard and Stern proposed on the fly signature scheme (PS-scheme), which aims at minimizing the on-line computa- tional work for a signer. In this paper, we propose more efficient on the fly signature schemes by improving the PS-scheme. In PS-scheme, the size of secret-key is fixed by modulus n, so that this feature leads to some drawbacks in

Takeshi Okamoto; Mitsuru Tada; Atsuko Miyaji

2001-01-01

229

Utility residential new construction programs: Going beyond the code. A report from the Database on Energy Efficiency Programs (DEEP) Project  

SciTech Connect

Based on an evaluation of 10 residential new construction programs, primarily sponsored by investor-owned utilities in the United States, we find that many of these programs are in dire straits and are in danger of being discontinued because current inclusion of only direct program effects leads to the conclusion that they are not cost-effective. We believe that the cost-effectiveness of residential new construction programs can be improved by: (1) promoting technologies and advanced building design practices that significantly exceed state and federal standards; (2) reducing program marketing costs and developing more effective marketing strategies; (3) recognizing the role of these programs in increasing compliance with existing state building codes; and (4) allowing utilities to obtain an ``energy-savings credit`` from utility regulators for program spillover (market transformation) impacts. Utilities can also leverage their resources in seizing these opportunities by forming strong and trusting partnerships with the building community and with local and state government.

Vine, E.

1995-08-01

230

Blackbody Spectrum  

NSDL National Science Digital Library

How does the blackbody spectrum of the sun compare to visible light? Learn about the blackbody spectrum of the sun, a light bulb, an oven, and the earth. Adjust the temperature to see the wavelength and intensity of the spectrum change. View the color of the peak of the spectral curve.

Simulations, Phet I.; Dubson, Michael; Perkins, Kathy; Adams, Wendy

2004-06-01

231

Non-streaming high-efficiency perforated semiconductor neutron detectors, methods of making same and measuring wand and detector modules utilizing same  

DOEpatents

Non-streaming high-efficiency perforated semiconductor neutron detectors, method of making same and measuring wands and detector modules utilizing same are disclosed. The detectors have improved mechanical structure, flattened angular detector responses, and reduced leakage current. A plurality of such detectors can be assembled into imaging arrays, and can be used for neutron radiography, remote neutron sensing, cold neutron imaging, SNM monitoring, and various other applications.

McGregor, Douglas S. (Riley, KS); Shultis, John K. (Manhattan, KS); Rice, Blake B. (Manhattan, KS); McNeil, Walter J. (Winnfield, KS); Solomon, Clell J. (Wichita, KS); Patterson, Eric L. (Manhattan, KS); Bellinger, Steven L. (Manhattan, KS)

2010-12-21

232

A General Framework for Wireless Spectrum Auctions  

Microsoft Academic Search

We propose a real-time spectrum auction framework to distribute spectrum among a large number wireless users under interference constraints. Our approach achieves conflict-free spectrum allocations that maximize auction revenue and spectrum utilization. Our design includes a compact and yet highly expressive bidding language, various pricing models to control tradeoffs between revenue and fairness, and fast auction clearing algorithms to compute

Sorabh Gandhi; Chiranjeeb Buragohain; Lili Cao; Haitao Zheng; Subhash Suri

2007-01-01

233

Utility of the social communication questionnaire-current and social responsiveness scale as teacher-report screening tools for autism spectrum disorders.  

PubMed

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 recommended cutoff scores in the manuals and extant literature, the teacher-completed SCQ and SRS yielded lower sensitivity and specificity values than would be desirable; however, lowering the cutoff scores on both instruments improved sensitivity and specificity to more adequate levels for screening purposes. Using the adjusted cutoff scores, the SRS teacher form appears to be a slightly better screener than the SCQ. Implications and limitations are discussed, as well as areas for future research. PMID:22143742

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

2012-08-01

234

A Basic Framework Analysis on the Needs of Radio Frequency Spectrum Allocation at Ultra High Frequency (UHF) Band for Digital Terrestrial TV Broadcasting in Indonesia  

Microsoft Academic Search

Presently, worldwide TV broadcasting system has begun shifting from analog to digital. Some factors taken into consideration for the implementation of the digital terrestrial TV broadcasting (DTTB) are improved quality of TV broadcasting, and the increased efficiency of spectrum usage. With the savings in bandwidth utilization, there will be spectrum available from analog TV broadcasting switch off, so called digital

D. Sirat; D. Setiawan; M. F. Mirza

2010-01-01

235

Improving the efficiency of feed utilization in poultry by selection. 1. Genetic parameters of anatomy of the gastro-intestinal tract and digestive efficiency  

Microsoft Academic Search

Background  Feed costs represent about 70% of the costs of raising broilers. The main way to decrease these costs is to improve feed efficiency\\u000a by modification of diet formulation, but one other possibility would be to use genetic selection. Understanding the genetic\\u000a architecture of the gastro-intestinal tract (GIT) and the impact of the selection criterion on the GIT would be of

Hugues de Verdal; Agnès Narcy; Denis Bastianelli; Hervé Chapuis; Nathalie Même; Séverine Urvoix; Elisabeth Le Bihan-Duval; Sandrine Mignon-Grasteau

2011-01-01

236

A review and assessment of the energy utilization efficiency in the Turkish industrial sector using energy and exergy analysis method  

Microsoft Academic Search

Exergy has been seen a key component for a sustainable society, and in the recent years exergy analysis has been widely used in the design, simulation and performance evaluation of thermal and thermo chemical systems. A particular thermo dynamical system is the society of a country, while the energy utilization of a country can be assessed using exergy analysis to

Zafer Utlu; Arif Hepbasli

2007-01-01

237

STUDY OF PCB DESTRUCTION EFFICIENCY AND PERFORMANCE FOR A COAL-FIRED UTILITY BOILER. VOLUME 1. TEST AND EVALUATION  

EPA Science Inventory

The report gives results of an evaluation of the adequacy of a large coal-fired utility boiler for disposal of oils containing 50-499 ppm of PCBs under conditions set by the PCB Disposal Regulations. TVA's Widows Creek Boiler No. 1 was used for the tests. In these tests, all effl...

238

High Prescription Drug Utilization and Associated Costs among Medicaid-eligible Children with Autism Spectrum Disorders Identified by a Population-based Surveillance Network  

PubMed Central

Purpose This study assessed medication use and associated costs among 8- and 15-yearold children with autism spectrum disorders (ASD) identified by the South Carolina Autism and Developmental Disabilities Monitoring (SCADDM) Network. Methods All Medicaid-eligible SCADDM-identified children with ASD from surveillance years 2006 and 2007 were included (n=263). Children were classified as ASD cases when documented behaviors consistent with the DSM-IV-TR criteria for autistic disorder, Asperger disorder, or pervasive developmental disorder- not otherwise specified (PDD-NOS) were present in health and education evaluation records. Medication and cost data were obtained by linking population-based and Medicaid data. Results All 263 SCADDM-identified children had Medicaid data available; 56% (n=147) had a prescription of any type, 40% (n=105) used psychotropic medication, and 20% (n=52) used multiple psychotropic classes over the study period. Common combinations were (1) attention deficit hyperactivity disorder (ADHD) medications and an antihypertensive, antidepressant or antipsychotic; and (2) antidepressants and an antipsychotic. Multiple psychotropic classes were more common among older children. Both the overall distribution of the number of prescription claims and medication costs varied significantly by age. Conclusions Results confirm that medication use in ASD, alone or in combination, is common, costly, and may increase with age.

Logan, Sarah L.; Nicholas, Joyce S.; Carpenter, Laura A.; King, Lydia B.; Garrett-Mayer, Elizabeth; Charles, Jane M.

2011-01-01

239

Development of an Advanced Deshaling Technology to Improve the Energy Efficiency of Coal Handling, Processing, and Utilization Operations  

SciTech Connect

The concept of using a dry, density-based separator to achieve efficient, near-face rock removal, commonly referred to as deshaling, was evaluated in several applications across the U.S.. Varying amounts of high-density rock exist in most run-of-mine feed. In the central Appalachian coalfields, a rock content exceeding 50% in the feed to a preparation plant is commonplace due to high amounts of out-of-seam dilution made necessary by extracting coal from thin seams. In the western U.S, an increase in out-of-seam dilution and environmental regulations associated with combustion emissions have resulted in a need to clean low rank coals and dry cleaning may be the only option. A 5 ton/hr mobile deshaling unit incorporating a density-based, air-table technology commercially known as the FGX Separator has been evaluated at mine sites located within the states of Utah, Wyoming, Texas, West Virginia, Virginia, Pennsylvania and Kentucky. The FGX technology utilizes table riffling principles with air as the medium. Air enters through the table and creates a fluidized bed of particles comprised of mostly fine, high density particles. The high density particle bed lifts the low-density coal particles to the top of the bed. The low-density coal moves toward the front of the table due to mass action and the downward slope of the table. The high-density particles settle through the fluidized particle bed and, upon making contact with the table, moves toward the back of the table with the assistance of table vibration. As a result, the low-density coal particles exit the front of the table closest to the feed whereas the high-density, high-ash content particles leave on the side and front of the table located at the farthest from the feed entry. At each test site, the run-of-mine feed was either directly fed to the FGX unit or pre-screened to remove the majority of the -6mm material. The surface moisture of the feed must be maintained below 9%. Pre-screening is required when the surface moisture of the feed coal exceeds the maximum limit. However, the content of -6mm in the feed to the FGX separator should be maintained between 10% and 20% to ensure an adequate fluidized bed. A parametric evaluation was conducted using a 3-level experimental design at each test site to identify the optimum separation performance and parameter values. The test data was used to develop empirical expressions that describe the response variables (i.e., mass yield and product ash content) as a function of the operating parameter values. From this process, it was established that table frequency and longitudinal slope are the most critical factors in controlling both mass yield and clean coal ash while the cross table slope was the least significant. Fan blower frequency is a critical parameter that controls mass yield. Although the splitter positions between product and middling streams and the middling and tailing streams were held constant during the tests, a separate evaluation indicated that performance is sensitive to splitter position within certain lengths of the table and insensitive in others. For a Utah bituminous coal, the FGX separator provided clean coal ash contents that ranged from a low of 8.57% to a high of 12.48% from a feed coal containing around 17% ash. From the 29 tests involved in the statistically designed test program, the average clean coal ash content was 10.76% while the tailings ash content averaged around 72%. One of the best separation performances achieved an ash reduction from 17.36% to 10.67% while recovering 85.9% of the total feed mass, which equated to an ash rejection value of around 47%. The total sulfur content was typically decreased from 1.61% to 1.49%. These performances were quantified by blending the middlings stream with the clean coal product. At a second Utah site, coal sources from three different bituminous coal seams were treated by the FGX deshaling unit. Three parameter values were varied based on the results obtained from Site No. 1 to obtain the optimum results shown in Table E-1. Approximately 9 tests w

Rick Honaker; Gerald Luttrell

2007-09-30

240

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

PubMed Central

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.

Chakravarti, A

1983-01-01

241

An efficient cryopreservation procedure for potato ( Solanum tuberosum L.) utilizing the new ice blocking agent, Supercool X1000  

Microsoft Academic Search

Cryopreservation has been recognized as a practical and efficient tool for long-term storage of vegetatively propagated plants. This study was conducted to investigate effects of modified vitrification techniques on cryopreservation of potato. In vitro plants of potato cultivars ‘Superior’ and ‘Atlantic’ were cold acclimated, and axillary buds were precultured, osmoprotected, exposed to PVS-2 solution, plunged into liquid nitrogen, thawed, and

M. A. Zhao; Y. Z. Xhu; S. P. Dhital; D. M. Khu; Y. S. Song; M. Y. Wang; H. T. Lim

2005-01-01

242

Effect of diets containing raw and extrusion?cooked rice bran on growth and efficiency of food utilization of broilers  

Microsoft Academic Search

1. Meat strain chicks were fed on diets containing 600 g rice bran\\/kg for the 7 to 8 week period required to reach broiler weight.2. Extrusion cooking of rice bran resulted, in improved chick weight gain and food efficiency for the first two weeks of feeding, but this advantage was lost by the end of the feeding period.3. Addition of

R. N. Sayre; L. Earl; F. H. Kratzer; R. M. Saunders

1988-01-01

243

Utility of NCCLS guidelines for identifying extended-spectrum beta-lactamases in non-Escherichia coli and Non-Klebsiella spp. of Enterobacteriaceae.  

PubMed

NCCLS screening and confirmation methods for detecting extended-spectrum beta-lactamases (ESBLs) apply only to Escherichia coli and Klebsiella spp., yet ESBLs have been found in other members of the family Enterobacteriaceae. We evaluated the effectiveness of NCCLS methods for detecting ESBLs in 690 gram-negative isolates of Enterobacteriaceae that excluded E. coli, Klebsiella pneumoniae, and Klebsiella oxytoca. Isolates were collected between January 1996 and June 1999 from 53 U.S. hospitals participating in Project ICARE (Intensive Care Antimicrobial Resistance Epidemiology). The antimicrobial susceptibility patterns of the isolates were determined by using the NCCLS broth microdilution method (BMD), and those isolates for which the MIC of ceftazidime, cefotaxime, ceftriaxone, or aztreonam was >or=2 microg/ml or the MIC of cefpodoxime was >or=8 microg/ml (positive ESBL screen test) were further tested for a clavulanic acid (CA) effect by BMD and the disk diffusion method (confirmation tests). Although 355 (51.4%) of the isolates were ESBL screen test positive, only 15 (2.2%) showed a CA effect. Since 3 of the 15 isolates were already highly resistant to the five NCCLS indicator drugs, ESBL detection would have an impact on the reporting of only 1.7% of the isolates in the study. Only 6 of the 15 isolates that showed a CA effect contained a bla(TEM), bla(SHV), bla(CTX-M), or bla(OXA) beta-lactamase gene as determined by PCR (with a corresponding isoelectric focusing pattern). Extension of the NCCLS guidelines for ESBL detection to Enterobacteriaceae other than E. coli and Klebsiella spp. does not appear to be warranted in the United States at present, since the test has poor specificity for this population and would result in changes in categorical interpretations for only 1.7% of Enterobacteriaceae tested. PMID:14715768

Schwaber, Mitchell J; Raney, Patti M; Rasheed, J Kamile; Biddle, James W; Williams, Portia; McGowan, John E; Tenover, Fred C

2004-01-01

244

ZnO:Al cathode for highly efficient, semitransparent 4% organic solar cells utilizing TiOx and aluminum interlayers  

NASA Astrophysics Data System (ADS)

We report on the fabrication of highly efficient, semitransparent bulk heterojunction solar cells comprising poly[[9-(1-octylnonyl)-9h-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT) blended with [6,6]-phenyl-C71-butyric acid methyl (PC71BM) esters as active layer. As semitransparent cathode sputtered aluminum doped ZnO was used in combination with a sputter damage preventing, thin (8 nm) TiOx layer processed from solution and a sputtered aluminum interlayer (ALI). The short circuit current improves for thicker ALIs due to increased reflectance at the cathode leading to average efficiencies of 4.0% for semitransparent solar cells. Comparable results (3.9%) were achieved for devices comprising thick absorbers and thin ALIs.

Bauer, Andreas; Wahl, Tina; Hanisch, Jonas; Ahlswede, Erik

2012-02-01

245

How DRB-XCL burners and air heater upgrade reduced NO sub x and improved efficiency at a western utility  

SciTech Connect

The Neil Simpson Unit is a 220,000 lb/hr pulverized coal boiler that was designed to fire a local Wyoming subbituminous coal. During the late 1980s, the Wyoming Department of Air Quality imposed emission limits on the Black Hills Power and Light Co., Neil Simpson Station. The new limits required Black Hills power to control not only particulate and sulfur dioxide (SO{sub 2}) emissions, but also nitrogen oxide (NO{sub x}) emissions. At the same time, Black Hills Power initiated an efficiency improvement study at Neil Simpson Station to investigate methods for reducing net electrical generation costs. This paper addresses the plant efficiency and emissions studies, startup activities, the operating problems and successful operating solutions for NO{sub x} control when firing a Wyoming subbituminous coal. Also included is a summary of the post-0retrofit boiler performance data.

Becker, W. (Babcock and Wilcox Co., Barberton, OH (US)); Stalcup, T.; Schild, V. (Black Hills Power and Light Co., Neil Simpson Station, Gillette, WY (US)); Kowalski, E. (Stone and Webster Engineering Corp., Denver, CO (US))

1992-01-01

246

Trigeneration scheme for energy efficiency enhancement in a natural gas processing plant through turbine exhaust gas waste heat utilization  

Microsoft Academic Search

â–º Efficiency enhancement of Natural Gas (NG) processing plants in hot\\/humid climates. â–º Gas turbine waste heat powered trigeneration scheme using absorption refrigeration. â–º Annual NG savings of 1879 MSCM and operating cost savings of US$ 20.9 million realized. â–º Trigeneration scheme payback period estimated at approximately 1year. â–º Significant economical and environmental benefits for NG processing plants.

Sahil Popli; Peter Rodgers; Valerie Eveloy

2012-01-01

247

Efficient grazing and utilization of the marine cyanobacterium Synechococcus sp. by larvae of the bivalve Mercenaria mercenaria  

Microsoft Academic Search

Efficient grazing by marine bivalve larvae has been thought to be limited to particles larger than 4 µm in diameter, thereby eliminating photosynthetic and non-photosynthetic picoplankton as contributers to larval diets. Documentation of ingestion, carbon retention and growth of laboratory-reared larvae of the bivalve Mercenaria mercenaria L. on Synechococcus sp. (WH7803), a small unicellular cyanobacterium 1 µm in diameter, was

S. M. Gallager; J. B. Waterbury; D. K. Stoecker

1994-01-01

248

Strain engineering by genome mass transfer: efficient chromosomal trait transfer method utilizing donor genomic DNA and recipient recombineering hosts.  

PubMed

Strain engineering, like cloning, is a fundamental technology used to confer new traits onto existing strains. While effective methods for trait development through gene modification within strains have been developed, methods for trait transfer between Escherichia coli strains to create complex strains are needed. We report herein the development of genome mass transfer (GMT), a broadly applicable new strain engineering methodology enabling rapid trait transfer from a donor strain into a recombineering gene-expressing recipient strain. GMT utilizes electroporation of donor chromosomal DNA into a recombineering recipient cell for precise trait transfer. GMT transfer of traits between E. coli strains can be used to rapidly assemble new strains incorporating combinations of marked gene knockouts, for example, utilizing the existing E. coli K-12 Keio gene knockout collection as source target genes. Optional use of random primed isothermal amplified DNA eliminates the need for initial DNA purification, affording high throughput application. This allows unprecedented simplicity and speed for rational design engineering of complex phenotypes in industrial strains. PMID:19455439

Williams, James A; Luke, Jeremy; Hodgson, Clague

2009-05-20

249

Efficiency Stabilization in Blue Organic Light-Emitting Devices Fabricated Utilizing a Double Emitting Layer with Fluorescence and Phosphorescence Doped Layers  

Microsoft Academic Search

The luminance efficiency of the blue organic light-emitting devices (OLEDs) fabricated utilizing a double emitting layer (DEML) with a 4,4?-Bis(2,2-diphenyl-ethen-1-yl)diphenyl (DPVBi) layer doped with 4,4?-Bis[4-(diphenylamino)styryl]biphenyl (BDAVBi) fluorescence dopant and a 4,4?-Bis(carbazol-9-yl)biphenyl (CBP) layer doped with a bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium III (FIrpic) phosphorescence dopant at 20 mA\\/cm was 6.2 cd\\/A, indicative of highly efficient OLEDs. Electroluminescence spectra for the OLEDs with a DEML showed that

H. S. Bang; D. C. Choo; T. W. Kim; J. H. Park; J. H. Seo; Y. K. Kim

2009-01-01

250

Variation in the apparent sensitivity of the insulin-mediated inhibition of proteolysis to amino acid supply determines the efficiency of protein utilization.  

PubMed

1. The variability between normal individuals in the efficiency of postprandial protein utilization (PPU), a determinant of the apparent protein requirement, was examined in relation to the relative responses of protein synthesis and proteolysis to protein feeding by means of [1-13C]leucine turnover and balance studies.2. Twenty-five healthy adults were infused intravenously with L-[1-13C]leucine continuously for 9 h. This was started in the postabsorptive state (PA, 3 h) and followed by low-protein feeding (LP, 3 h), and then by isoenergetic high-protein feeding (HP, 3 h). This allowed protein intake to be varied against a constant postprandial insulin level so that the extent of any amino-acid-mediated responses which were additional to those exerted by insulin could be investigated. Leucine oxidation, O, and balance (intake-oxidation), protein synthesis, S, and degradation, D, were calculated from plasma [1-13C]alpha-ketoisocaproic acid enrichment and 13CO2 excretion.3.PPUprotein, calculated as change in leucine balance/change in intake (HP-LP), varied from 0.58 to 0.99 (mean=0. 81+/-0.10), independently of age or sex. PPUprotein varied directly with the inhibition of D and inversely with the increase in leucine concentration and stimulation of O and S.4. Efficient PPU, as demonstrated by the top quintile of individuals categorized in terms of PPUprotein, involves maximal inhibition of D by protein feeding with minimal increases in free amino acid concentrations, O and S. Lesser inhibition of D and greater stimulation of S and O characterized the lower, less efficient quintile. This indicates that the efficiency of protein utilization in individuals, and a component of their apparent protein requirement, is determined by the sensitivity of the insulin-mediated inhibition of proteolysis to amino acid supply. PMID:9831698

Fereday, A; Gibson, N R; Cox, M; Pacy, P J; Millward, D J

1998-12-01

251

Efficient succinic acid production from lignocellulosic biomass by simultaneous utilization of glucose and xylose in engineered Escherichia coli.  

PubMed

To enhance succinic acid formation during xylose fermentation in Escherichia coli, overexpression of ATP-forming phosphoenolpyruvate carboxykinase (PEPCK) from Bacillus subtilis 168 in an ldhA, pflB, and ppc deletion strain resulted in a significant increase in cell mass and succinic acid production. However, BA204 displays a low yield of glucose fermentation and sequential glucose-xylose utilization under regulation by the phosphotransferase system (PTS). To improve the capability of glucose fermentation and simultaneously consume sugar mixture for succinic acid production, a pflB, ldhA, ppc, and ptsG deletion strain overexpressing ATP-forming PEPCK, named E. coli BA305, was constructed. As a result, after 120h fed-batch fermentation of sugarcane bagasse hydrolysate, the dry cell weight and succinic acid concentration in BA305 were 4.58gL(-1) and 39.3gL(-1), respectively. PMID:24096277

Liu, Rongming; Liang, Liya; Li, Feng; Wu, Mingke; Chen, Kequan; Ma, Jiangfeng; Jiang, Min; Wei, Ping; Ouyang, Pingkai

2013-09-20

252

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."

2008-02-15

253

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

SciTech Connect

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.

Claudio Filippone, Ph.D.

1999-06-01

254

High efficiency, quasi-instantaneous steam expansion device utilizing fossil or nuclear fuel as the heat source  

SciTech Connect

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.

Claudio Filippone, Ph.D.

1999-06-01

255

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

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 several investigations of various aspects of the system. Taken as a whole, they confirm significant progress towards the technical feasibility of this technology.

Byard D. Wood; Jeff D. Muhs

2003-01-01

256

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

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.

Byard D. Wood; Jeff D. Muhs

2002-09-01

257

Speed control of a PV powered DC motor driving a self-excited 3-phase induction generator for maximum utilization efficiency  

SciTech Connect

Photovoltaic (PV) powered dc motors driving dedicated loads (e.g., water pumps) are increasingly used in the remote rural areas of may developing countries. The key to their success is simplicity (direct coupling, no dc-ac conversion, no storage batteries, etc.). Because of the relatively high cost of the PV array, the system designer is interested in maximizing its utilization efficiency. A PV powered dc motor can also be used to drive a three-phase self-excited induction generator (SEIG). This arrangement is useful as part of an integrated renewable energy system (IRES), which takes advantage of the inherent diversity of wind and solar energy in most developing countries to improve power quality. The SEIG is driven by a wind-turbine, dc motor, or both. Another advantage of this arrangement is its versatile control characteristics through the dc motor control. This paper describes a technique to maximize the utilization efficiency of the PV array by controlling the field current of the dc motor through a dc chopper.

Alghuwainem, S.M. [King Saud Univ., Riyadh (Saudi Arabia). Electrical Engineering Dept.

1996-12-01

258

Altered expression of the PTR/NRT1 homologue OsPTR9 affects nitrogen utilization efficiency, growth and grain yield in rice.  

PubMed

The plant PTR/NRT1 (peptide transporter/nitrate transporter 1) gene family comprises di/tripeptide and low-affinity nitrate transporters; some members also recognize other substrates such as carboxylates, phytohormones (auxin and abscisic acid), or defence compounds (glucosinolates). Little is known about the members of this gene family in rice (Oryza sativa L.). Here, we report the influence of altered OsPTR9 expression on nitrogen utilization efficiency, growth, and grain yield. OsPTR9 expression is regulated by exogenous nitrogen and by the day-night cycle. Elevated expression of OsPTR9 in transgenic rice plants resulted in enhanced ammonium uptake, promotion of lateral root formation and increased grain yield. On the other hand, down-regulation of OsPTR9 in a T-DNA insertion line (osptr9) and in OsPTR9-RNAi rice plants had the opposite effect. These results suggest that OsPTR9 might hold potential for improving nitrogen utilization efficiency and grain yield in rice breeding. PMID:23231455

Fang, Zhongming; Xia, Kuaifei; Yang, Xin; Grotemeyer, Marianne Suter; Meier, Stefan; Rentsch, Doris; Xu, Xinlan; Zhang, Mingyong

2012-12-11

259

Improvement of efficiency and stability utilizing a wide band gap material as the host for red organic light-emitting diodes  

NASA Astrophysics Data System (ADS)

We present red organic light-emitting diodes (OLEDs) with high efficiency and stability based on a wide band gap host material 9,10-di (2-naphthyl) anthracene (ADN). In these diodes, N,N'-bis(1-naphthyl)-N,N'-diphenyl-1, 1'-biphenyl-4,4'diamine(NPB) and tris-(8- ydroxy-quinoline) aluminium (Alq) are used as hole and electron transport layers, respectively. 2,3,6,7-tetrahydro-1,1,7,7,-tetramethyl- 1H,5H,11H-10-(2-benzothiazolyl) quinolizino-[9,9a,1gh] coumarin (C545T) and 4-(dicyano-methylene)-2- t-butyl-6-(1,1,7,7-tetramethyl-julolidyl-9-enyl)-4H-pyran (DCJTB) are co-doped into the ADN emitting layer. Utilizing the two-step energy transfer from ADN to C545T and then from C545T to DCJTB, we achieved pure red organic light-emitting devices, which showed improved optical and electrical characteristics. Compared with devices where the emitting layer is made of Alq and DCJTB, the emission efficiency and stability of the ADN-based devices are greatly improved and the turn-on voltage is also decreased. The co-doping technique provides a promising way of utilizing wide band gap materials as the host to make red OLEDs, which will be useful in improving the electroluminesent performance of devices and simplifying the process of fabricating full colour OLEDs.

Tang, Hao; Li, Ying; Wang, Xiuru; Wang, Wengen; Sun, Runguang

2007-03-01

260

An efficient (1)H/(31)P double-resonance solid-state NMR probe that utilizes a scroll coil.  

PubMed

The construction and performance of a scroll coil double-resonance probe for solid-state NMR on stationary samples is described. The advantages of the scroll coil at the high resonance frequencies of (1)H and (31)P include: high efficiency, minimal perturbations of tuning by a wide range of samples, minimal RF sample heating of high dielectric samples of biopolymers in aqueous solution, and excellent RF homogeneity. The incorporation of a cable tie cinch for mechanical stability of the scroll coil is described. Experimental results obtained on a Hunter Killer Peptide 1 (HKP1) interacting with phospholipid bilayers of varying lipid composition demonstrate the capabilities of this probe on lossy aqueous samples. PMID:17719813

Grant, Christopher V; Sit, Siu-Ling; De Angelis, Anna A; Khuong, Kelli S; Wu, Chin H; Plesniak, Leigh A; Opella, Stanley J

2007-08-06

261

Frequency Spectrum.  

National Technical Information Service (NTIS)

Uses a pictorial representation of the frequency spectrum to identify power frequencies, audio frequencies, radio frequencies, VhF, UhF, and microwaves. Given a specific wavelength, calculates the frequency. Given either frequency or wavelength, calculate...

1994-01-01

262

Structure-guided alteration of coenzyme specificity of formate dehydrogenase by saturation mutagenesis to enable efficient utilization of NADP+.  

PubMed

Formate dehydrogenase from Candida boidinii (CboFDH) catalyses the oxidation of formate anion to carbon dioxide with concomitant reduction of NAD(+) to NADH. CboFDH is highly specific to NAD(+) and virtually fails to catalyze the reaction with NADP(+). Based on structural information for CboFDH, the loop region between beta-sheet 7 and alpha-helix 10 in the dinucleotide-binding fold was predicted as a principal determinant of coenzyme specificity. Sequence alignment with other formate dehydrogenases revealed two residues (Asp195 and Tyr196) that could account for the observed coenzyme specificity. Positions 195 and 196 were subjected to two rounds of site-saturation mutagenesis and screening and enabled the identification of a double mutant Asp195Gln/Tyr196His, which showed a more than 2 x 10(7)-fold improvement in overall catalytic efficiency with NADP(+) and a more than 900-fold decrease in the efficiency with NAD(+) as cofactors. The results demonstrate that the combined polar interactions and steric factors comprise the main structural determinants responsible for coenzyme specificity. The double mutant Asp195Gln/Tyr196His was tested for practical applicability in a cofactor recycling system composed of cytochrome P450 monooxygenase from Bacillus subtilis, (CYP102A2), NADP(+), formic acid and omega-(p-nitrophenyl)dodecanoic acid (12-pNCA). Using a 1250-fold excess of 12-pNCA over NADP(+) the first order rate constant was determined to be equal to k(obs) = 0.059 +/- 0.004 min(-1). PMID:18616465

Andreadeli, Aggeliki; Platis, Dimitris; Tishkov, Vladimir; Popov, Vladimir; Labrou, Nikolaos E

2008-07-04

263

Utility of adsorbents in the purification of drinking water: a review of characterization, efficiency and safety evaluation of various adsorbents.  

PubMed

Clean drinking water is one of the implicit requisites fora healthy human population. However the growing industrialization and extensive use of chemicals for various concerns, has increased the burden of unwanted pollutants in the drinking water of developing countries like India. The entry of potentially hazardous substances into the biota has been magnifying day by day. In the absence of a possible stoppage of these, otherwise, useful chemicals, the only way to maintain safer water bodies is to develop efficient purifying technologies. One such immensely beneficial procedure that has been in use is that of purification of water using 'adsorbents'. Indigenous minerals and natural plants products have potential for removing many pollutants viz. fluoride, arsenic, nitrate, heavy metals, pesticides as well as trihalomethanes. Adsorbents which are derived from carbon, alumina, zeolite, clay minerals, iron ores, industrial by products, and natural products viz. parts of the plants, herbs and algal biomass offer promising potential of removal. In the recent years attention has been paid to develop process involving screening/pretreatment/activation/impregnation using alkalies, acids, alum, lime, manganese dioxide, ferric chloride and other chemicals which are found to enhance their adsorbing efficiency. Chemical characterization of these adsorbents recapitulates the mechanism of the process. It is imperative to observe that capacities of the adsorbents may vary depending on the characteristics, chemical modifications and concentration of the individual adsorbent. Removal kinetics is found to be based on the experimental conditions viz. pH, concentration of the adsorbate, quantity of the adsorbent and temperature. It is suggested that isotherm model is suitable tool to assess the adsorption capacities in batch and column modes. Safety evaluation and risk assessment of the process/products may be useful to provide guidelines for its sustainable disposal. PMID:20120453

Dubey, Shashi Prabha; Gopal, Krishna; Bersillon, J L

2009-05-01

264

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

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.

Byard D. Wood; David L. Beshears

2006-02-01

265

Effects of Powdery Mildew Infection on the Efficiency of CO2 Fixation and Light Utilization by Sugar Beet Leaves  

PubMed Central

Sugar beet leaves (Beta vulgaris L.) infected with powdery mildew (Erysiphe polygoni D.C.) show declining rates of net photosynthesis as the disease develops; relative to healthy controls, reductions of 35, 70, and 75% were observed at 9, 16, and 22 days after inoculation, respectively. A leaf gas exchange procedure in which an air stream flowed through the leaf showed that mesophyll conductance declined in parallel with photosynthesis in mildew-infected leaves. Viscous flow conductance of diseased leaves also declined over the same period suggesting that stomatal aperture was reduced. From the magnitude and time course of disease effects on stomatal aperture and mesophyll conductance, it appears that the effects at the mesophyll level were primarily responsible for mediating the decline in net photosynthesis. Changes in mesophyll conductance were closely correlated with reduced activity of ribulose-1,5-bisphosphate carboxylase on a leaf area basis. This decrease could be attributed to a reduction in the concentration of the enzyme, a reduction which was greater than the reduction in total soluble protein. The quantum efficiency of light use was also decreased by the disease. Mildew-infected leaves had quantum yields that were reduced, relative to healthy leaves, by 17 and 22% at 14 and 18 days after inoculation, respectively.

Gordon, Thomas R.; Duniway, John M.

1982-01-01

266

An efficient cryopreservation procedure for potato (Solanum tuberosum L.) utilizing the new ice blocking agent, Supercool X1000.  

PubMed

Cryopreservation has been recognized as a practical and efficient tool for long-term storage of vegetatively propagated plants. This study was conducted to investigate effects of modified vitrification techniques on cryopreservation of potato. In vitro plants of potato cultivars "Superior" and "Atlantic" were cold acclimated, and axillary buds were precultured, osmoprotected, exposed to PVS-2 solution, plunged into liquid nitrogen, thawed, and finally planted in the regeneration medium. In the modified vitrification technique an ice-blocking agent, Supercool X1000, was added with PVS-2 solution. Cold acclimation affected survival of cryopreserved shoot tips, and the highest survival (46.7%) was obtained after 3 weeks of acclimation at 10 degrees C. Shoot tips exposed to 2M glycerol plus 0.6M sucrose for 40 min gave 51.5% and 11.7% survival in "Atlantic" and "Superior" at 10 degrees C, respectively. Cold acclimated and osmoprotected shoot tips were dehydrated with PVS-2 containing different concentrations of Supercool X1000 prior to a plunge into liquid nitrogen. Treatments with 0.1% and 1% of Supercool X1000 significantly improved survival by 55% in "Superior" and 71.3% in "Atlantic", respectively. After cryopreservation, vitrified shoot tips resumed growth within a week in a medium (1 mg l(-1) GA(3), 0.5 mg l(-1) zeatin, and 0.1 mg l(-1) IAA) with a low level of Pluronic F-68 (0.005%) and survival was 33.7% higher in "Atlantic" and 14.7% higher in "Superior" than the control (without Pluronic F-68). PMID:15864594

Zhao, M A; Xhu, Y Z; Dhital, S P; Khu, D M; Song, Y S; Wang, M Y; Lim, H T

2005-04-28

267

The effect of x-ray beam quality and geometry on radiation utilization efficiency in multidetector CT imaging  

SciTech Connect

This study has the following objectives: To measure the geometric efficiency (GE) of a multidetector CT (MDCT) system and investigate its dependence on several exposure parameters and to correlate GE with radiation dose burden of patients undergoing MDCT imaging. Dose profiles for all available beam collimations, tube voltage values, focal spot sizes, and modes of operation were determined for a modern MDCT scanner using an array of thermoluminescent chip dosimeters positioned side by side. Dose profiles measured free-in-air and at the center and periphery of the standard polymethyl methacrylate (PMMA) phantoms were used to estimate GE. The standard free-in-air and a new measure of GE determined using the standard PMMA phantoms were correlated with volume computed tomography dose index normalized to the z-axis coverage per rotation which is directly related to patient radiation dose burden. GE was found to be from 30% to 88% as beam collimation was changed from 1.2 to 24 mm, with thin beam collimations corresponding to higher ''wasted'' dose. For the same tube voltage and beam collimation, the use of small focal spot was associated with higher GE compared to the large focal spot. Besides, beam quality was found to have a much weaker effect on the GE value. In comparison to free-in-air, a weighted GE determined using the standard PMMA phantoms was found to have significantly better correlation with patient radiation burden (p<0.05). Overbeaming strongly depends on the beam collimation and focal spot size, while the impact of beam quality on GE is less pronounced. Thin beam collimations are associated with a GE of as low as 30%.

Perisinakis, Kostas; Papadakis, Antonios E.; Damilakis, John [Department of Medical Physics, Faculty of Medicine, University of Crete, P.O. Box 2208, 71003 Heraklion, Crete (Greece); Department of Medical Physics, University Hospital of Heraklion, P.O. Box 1352, 71110 Heraklion, Crete (Greece); Department of Medical Physics, Faculty of Medicine, University of Crete, P.O. Box 2208, 71003 Heraklion, Crete (Greece)

2009-04-15

268

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

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 small core or a large core 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 second generation (alpha) system, the secondary mirror is an ellipsoidal mirror that directs the visible light into a bundle of small-core fibers. The IR spectrum is filtered out to minimize unnecessary heating at the fiber entrance region. This report describes the following investigations of various aspects of the system: (1) Performance specifications were developed for the tracking subsystem and collector optics, (2) Thermal management experiments for the fiber optic bundle entrance region, and (3) Bioreactor testing, cost-modeling, and redesign. Much of the planned work has been slowed due to significant procurement delays of the primary mirror. However, taken as a whole, they do confirm progress towards the technical feasibility and commercial viability of this technology. Due to this procurement delay, a no-cost extension of the project completion date has been requested and approved.

Byard D. Wood; Jeff D. Muhs

2005-02-01

269

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

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 small core or a large core 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 second generation (alpha) system, the secondary mirror is an ellipsoidal mirror that directs the visible light into a bundle of small-core fibers. The IR spectrum is filtered out to minimize unnecessary heating at the fiber entrance region. This report describes the following investigations of various aspects of the system. Taken as a whole, they confirm significant progress towards the technical feasibility and commercial viability of this technology. (1) TRNSYS Modeling of a Hybrid Lighting System: Building Energy Loads and Chromaticity Analysis; (2) High Lumens Screening Test Setup for Optical Fibers; (3) Photo-Induced Heating in Plastic Optical Fiber Bundles; (4) Low-Cost Primary Mirror Development; (5) Potential Applications for Hybrid Solar Lighting; (6) Photobioreactor Population Experiments and Productivity Measurements; and (7) Development of a Microalgal CO2-Biofixation Photobioreactor.

Byard D. Wood; Jeff D. Muhs

2004-08-01

270

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

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.

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

1995-08-01

271

Enhancement of the luminance efficiency in blue organic light-emitting devices fabricated utilizing a hybrid phosphorescence and fluorescence emitting layer  

Microsoft Academic Search

Blue organic light-emitting devices (OLEDs) fabricated utilizing a hybrid emitting layer (EML) consisting of a bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridiumIII (FIrpic)-doped 1,3-bis(carbazol-9-yl)benzene (mCP) layer, a 2-methyl-9,10-bis(naphthalene-2-yl)anthracene (MADN)-doped mCP layer, and a 2,9-dimethyl-4,7-diphenyl-1,10-phenanthorlene (BCP)-doped MADN layer were fabricated to investigate their luminance efficiency enhancement. The FIrpic-doped mCP layer, the MADN-doped mCP layer, and the BCP-doped MADN layer in the blue OLEDs acted as a phosphorescence

Hyun Sung Bang; Hwan Seok Jeong; Dong Chul Choo; Tae Whan Kim

2011-01-01

272

Electromagnetic Spectrum Utilization: The Silent Crisis.  

National Technical Information Service (NTIS)

Most people know that radio, television, long distance telephone, radar, police radio, etc., play important roles in their daily lives. Many of the more thoughtful are aware that telecommunication services are important, indeed essential, participants in ...

1966-01-01

273

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)

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.

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

2001-04-01

274

Spectrum Management  

NASA Astrophysics Data System (ADS)

Present day life without the use of radio frequencies is totally unimaginable. The mode of usage of the different frequency bands is diverse and ever-changing with constant development of newer technology. In the midst of all this, there is a minority group of spectrum users who are labeled ``passive''. Radio astronomy and remote sensing groups come under this title, having no control over the signal they try to receive, they are often most vulnerable to interference from man-made radio waves. However, through constant need to develop new techniques to detect very week signal, the research done by these passive users of spectrum often benefits the commercial users. It is therefore of utmost importance that both the active and the passive users of radio spectrum may survive and grow together in a manner of peaceful coexistence. This is the goal of spectrum management. As radio waves ``do not know'' of any national boundaries, such management issues have to be agreed upon globally. The mechanisms that have been set up for such purposes with global and national counterparts is explained. How, as a minority, the interests of radio astronomy may be best served now and in future is also discussed.

Ghosh, Tapasi

2002-12-01

275

Power Generation Efficiency of Photovoltaics and a SOFC-PEFC Combined Micro-grid with Time Shift Utilization of the SOFC Exhaust Heat  

NASA Astrophysics Data System (ADS)

In this study, the combined system of a solid-oxide fuel cell (SOFC) and a proton-exchange membrane fuel cell (PEFC) is developed. The proposed system consists of a SOFC-PEFC combined system and a photovoltaic system (PV) as the energy supply to a micro-grid. The exhaust heat of the SOFC is used for the steam reforming of the bio-ethanol gas with time shift utilization of the exhaust heat of the SOFC in optional time. The SOFC-PEFC combined system with the PV was introduced in a micro-grid of 30 residences in Sapporo, Japan. The operation plan of the system has three cases: without solar power, with 50% and with 100% of solar output power. Moreover, three types of system operation of using the SOFC independent operation, PEFC independent operation and SOFC-PEFC combined system are used to supply the demand side. A comparative study between the types of system operation is presented. The power generation efficiency is investigated for different load patterns: average load pattern, compressed load pattern and extended load pattern. This paper reported that the power generation efficiencies of the proposedsystem in consideration of these load patterns are 27% to 48%.

El-Sayed, Abeer Galal; Obara, Shin'ya

276

Dynamic Spectrum Access to the Combined Resource of Commercial and Public Safety Bands Based on a WCDMA Shared Network  

NASA Astrophysics Data System (ADS)

The public safety spectrum is generally under-utilized due to the unique traffic characteristics of bursty and mission critical. This letter considers the application of dynamic spectrum access (DSA) to the combined spectrum of public safety (PS) and commercial (CMR) users in a common shared network that can provide both PS and CMR services. Our scenario includes the 700MHz Public/Private Partnership which was recently issued by the Federal Communications Commission. We first propose an efficient DSA mechanism to coordinate the combined spectrum, and then establish a call admission control that reflects the proposed DSA in a wideband code division multiple access based network. The essentials of our proposed DSA are opportunistic access to the public safety spectrum and priority access to the commercial spectrum. Simulation results show that these schemes are well harmonized in various network environments.

Jeon, Hyoungsuk; Im, Sooyeol; Kim, Youmin; Kim, Seunghee; Kim, Jinup; Lee, Hyuckjae

277

Temperature and food quality effects on growth, consumption and post-ingestive utilization efficiencies of the forest tent caterpillar Malacosoma disstria (Lepidoptera: Lasiocampidae).  

PubMed

Temperature and food quality can both influence growth rates, consumption rates, utilization efficiencies and developmental time of herbivorous insects. Gravimetric analyses were conducted during two consecutive years to assess the effects of temperature and food quality on fourth instar larvae of the forest tent caterpillar Malacosoma disstria Hübner. Larvae were reared in the laboratory at three different temperatures (18, 24 and 30 degrees C) and on two types of diet; leaves of sugar maple trees Acer saccharum Marsh. located at the forest edge (sun-exposed leaves) or within the forest interior (shade-exposed leaves). In general, larvae reared at 18 degrees C had lower growth rates and lower consumption rates than larvae reared at the warmer temperatures (24 and 30 degrees C). Moreover, the duration of the instar decreased significantly with increasing temperatures. Type of diet also affected the growth rates and amount of food ingested by larvae but did not affect the duration of the instar. Larvae fed sun-exposed leaves consumed more food and gained higher biomasses. Values of approximate digestibility and efficiency of conversion of ingested food were also higher when larvae were fed sun-exposed leaves. Higher growth rates with increasing temperatures were primarily the result of the shorter stadium duration. The higher growth rates of larvae fed sun-exposed leaves were possibly the result of stimulatory feeding and consequently greater food intake and also a more efficient use of food ingested. This study suggests that the performance of M. disstria caterpillars could be enhanced by warmer temperatures and higher leaf quality. PMID:12020370

Levesque, K R; Levesque, K R; Fortin, M; Mauffette, Y

2002-04-01

278

Efficient Utilization of SIMD Extensions  

Microsoft Academic Search

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

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

2005-01-01

279

Effects of dietary forage level and monensin on lactation performance, digestibility and fecal excretion of nutrients, and efficiency of feed nitrogen utilization of Holstein dairy cows.  

PubMed

Two experiments (Exp. 1 and 2) were conducted using a 4 x 4 Latin square design with 2 replications (n = 8) to evaluate effects of feeding Holstein dairy cows a total mixed ration containing 50 or 60% of ration dry matter (DM) from forages with or without supplementation of monensin. In Exp. 1, alfalfa silage (AS) was used as the major forage (55% forage DM), and corn silage (CS; 45% forage DM) was used to make up the rest of the forage portion of diets (55AS:45CS). In Exp. 2, CS was used as the major forage (70% forage DM) and alfalfa hay (AH; 30% forage DM) was used to make up the rest of the forage portion of diets (70CS:30AH). Experimental diets were arranged in a 2 x 2 factorial with 50 or 60% ration DM from forages and monensin supplemented at 0 or 300 mg/cow daily. In Exp. 1 (55AS:45CS), feeding 60% forage diets decreased DM intake (DMI; 27.3 vs. 29.6 kg/d) but maintained the same levels of milk (45.8 vs. 47.0 kg/d) compared with 50% forage diets. The efficiency of converting feed to milk or 3.5% fat-corrected milk was greater for cows fed 60% compared with 50% forage diets (1.7 vs. 1.6 kg milk or 3.5% fat-corrected milk/kg of DMI, respectively). Increasing dietary forage level from 50 to 60% of ration DM increased milk fat percentage (3.4 to 3.5%); however, adding monensin to the 60% forage diet inhibited the increase in milk fat percentage. Feeding 60% forage diets decreased feed cost, but this decrease ($0.5/head per day) in feed cost did not affect income over feed cost. Feeding 60% forage diets decreased fecal excretion of DM (10.6 to 9.6 kg/d) and nitrogen (N; 354 to 324 g/d) and improved apparent digestibility of neutral detergent fiber from 43 to 49% and apparent efficiency of feed N utilization from 32.3 to 35.9% compared with 50% forage diets. In Exp. 2 (70CS:30AH), feeding 60% forage diets decreased DMI from 29.6 to 28.2 kg but maintained the same level of milk (41.1 vs. 40.8 kg/d) and therefore increased the efficiency of converting feed to milk (1.46 vs. 1.38 kg milk/kg DMI) compared with 50% forage diets. Daily feed cost for feeding 60% forage diets was $0.3/head lower than for the 50% forage diets. Fecal excretion of DM (10.3 vs. 11.5 kg/d) was lower and fecal excretion of N (299 vs. 328 g/d) tended to be lower for 60% compared with 50% forage diets. Results from these 2 experiments suggest that a 60% forage diet consisting of either AS or CS as the major forage can be fed to high producing Holstein dairy cows without affecting milk production while improving or maintaining the efficiency of converting feed to milk and the apparent efficiency of utilization of feed N. Cows receiving a 60% forage diet had a similar or improved digestibility of nutrients with a similar or reduced fecal excretion of nutrients. Effects of monensin under the conditions of the current experiments were minimal. PMID:19528598

Martinez, C M; Chung, Y-H; Ishler, V A; Bailey, K W; Varga, G A

2009-07-01

280

Noble Roll-to-Roll Cohesive, Coated, Flexible, High-Efficiency Polymer Light-Emitting Diodes Utilizing ITO-Free Polymer Anodes.  

PubMed

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

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

2013-06-19

281

Absorption, emission spectrum properties, and efficient laser performances of Yb:Y{sub 3}ScAl{sub 4}O{sub 12} ceramics  

SciTech Connect

We report on the continuous-wave laser performances of Yb{sup 3+}-doped disordered Y{sub 3}Al{sub 5}O{sub 12}/Y{sub 3}Sc{sub 2}Al{sub 4}O{sub 12} (YAG/YSAG) ceramics fabricated by sintering method. These materials exhibit relatively low minimum pump intensity (I{sub min}) and broad emission bandwidth even in the yttrium aluminum garnet systems. The value of I{sub min} in the Yb:Y{sub 3}ScAl{sub 4}O{sub 12} ceramics was found to be 2/3 compared with the Yb:YAG single crystal under 970 nm zero-line pumping. Efficient laser oscillation of 72% slope efficiency was obtained for input pump power. These materials attract great interest for high power femtosecond microchip lasers and amplifier applications.

Saikawa, J.; Sato, Y.; Taira, T.; Ikesue, A. [Laser Research Center for Molecular Science, Institute for Molecular Science, 38 Nishigonaka, Myodaiji, Okazaki 444-8585 (Japan); Materials Research and Development Laboratory, Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atsuta-ku, Nagoya 456-8587 (Japan)

2004-09-13

282

EBI1-ligand chemokine (ELC) attracts a broad spectrum of lymphocytes: activated T cells strongly up-regulate CCR7 and efficiently migrate toward ELC  

Microsoft Academic Search

EBI1-ligand chemokine (ELC) is a CC chemokine constitutively expressed in various lymphoid tissues and a high-affinity functional ligand for EBI1\\/CCR7, a seven transmembrane G-protein- coupled receptor originally identified as an Epstein-Barr virus (EBV)-inducible gene. Here we examined chemotactic activity of ELC on peripheral blood leukocytes. ELC attracted both CD4F and CD8F T cells, particularly efficiently after activation with IL-2 or

Ryu Yoshida; Morio Nagira; Toshio Imai; Masataka Baba; Shin Takagi; Youichi Tabira; Junji Akagi; Hisayuki Nomiyama; Osamu Yoshie

1998-01-01

283

On Spectrum Selection Games in Cognitive Radio Networks  

Microsoft Academic Search

Cognitive Radio Networks aim at enhancing spec- trum utilization by allowing cognitive devices to opportunistically access vast portions of the spectrum. To reach such ambitious goal, cognitive terminals must be geared with enhanced spectrum management capabilities including the detection of unused spec- trum holes (spectrum sensing), the characterization of available bands (spectrum decision), the coordination with other cognitive devices in

Ilaria Malanchini; Matteo Cesana; Nicola Gatti

2009-01-01

284

A Novel Spectrum Allocation Mechanism Based on Graph Coloring and Bidding Theory  

Microsoft Academic Search

Cognitive radios (CRs) have a potential to improve spectrum utilization by enabling users to access the spectrum dynamically without disturbing licensed primary users (PUs). In this paper, we consider the spectrum allocation in wireless networks with multiple selfish secondary users (SUs) and a spectrum pool formed by underutilized spectrum of primary users. A novel spectrum allocation mechanism is proposed to

Yutao Liu; Guisen Xu; Xuezhi Tan

2009-01-01

285

Biomass utilization  

SciTech Connect

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).

Coute, W.A. (ed.)

1983-01-01

286

Improved full spectrum cloudy scene simulation  

NASA Astrophysics Data System (ADS)

This paper will discuss recent improvements made to the MCScene code, a high fidelity model for full optical spectrum (UV through LWIR) hyperspectral image (HSI) simulation. MCScene provides an accurate, robust, and efficient means to generate HSI scenes for algorithm validation. MCScene utilizes a Direct Simulation Monte Carlo approach for modeling 3D atmospheric radiative transfer (RT) including full treatment of molecular absorption and Rayleigh scattering, aerosol absorption and scattering, and multiple scattering and adjacency effects, as well as scattering from spatially inhomogeneous surfaces, including surface BRDF effects. The model includes treatment of land and ocean surfaces, 3D terrain, 3D surface objects, and effects of finite clouds with surface shadowing. This paper will provide an overview of how RT elements are incorporated into the Monte Carlo engine. Several new examples of the capabilities of MCScene to simulate 3-dimensional cloud fields will also be discussed, and sample calculations will be presented.

Sundberg, Robert; Richtsmeier, Steven; Haren, Raymond

2008-10-01

287

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

PubMed Central

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.

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

288

Decline in topsoil microbial quotient, fungal abundance and C utilization efficiency of rice paddies under heavy metal pollution across South China.  

PubMed

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 qCO(2) are proved better indicative of heavy metal impacts on microbial community structure and activity. The potential effects of these changes on C cycling and CO(2) production in the polluted rice paddies deserve further field studies. PMID:22701725

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

2012-06-11

289

Numerical study of the efficiency of a CO-laser oscillation on overtone or fundamental transitions depending on the lasing spectrum width  

SciTech Connect

A numerical model taking into account the multiquantum vibrational-vibrational exchange processes is developed for simulating a CO laser on a CO-N{sub 2} mixture. The energy characteristics of a CO laser operating either on overtone or fundamental transitions, depending on the number of vibrational-rotational transitions falling within the band of a selective resonator, are studied theoretically. Particular emphasis is placed on forecasting the efficiency of narrow-band lasing (on one, three, and five transitions) depending on the position of the centre of the filter's spectral window and the resonator Q factor. It is shown that using the approximation of the single-quantum vibrational-vibrational exchange introduces a considerable error in the calculation of the characteristics of a CO laser with a narrow-band filter (1-5 transitions). The law of the increase in the lasing energy with increasing the spectral-filter bandwidth (from one to 35 transitions), the centre frequency of which corresponds to the 23{yields}22 and 24{yields}22 transitions for the fundamental and overtone bands, respectively, is studied. It is shown that, even for lasing on five neighbouring transitions, the output energy exceeds 50% of the energy achieved in the free-running mode. (lasers)

Kurnosov, A K; Napartovich, A P [State Research Center of Russian Federation 'Troitsk Institute for Innovation and Fusion Research', Troitsk, Moscow Region (Russian Federation); Shnyrev, S L [Moscow Engineering Physics Institute (State University), Moscow (Russian Federation)

2004-11-30

290

Monte Carlo simulation of a PhosWatch detector using Geant4 for xenon isotope beta-gamma coincidence spectrum profile and detection efficiency calculations.  

PubMed

A simulation tool has been developed using the Geant4 Toolkit to simulate a PhosWatch single channel beta-gamma coincidence detection system consisting of a CsI(Tl)/BC404 Phoswich well detector and pulse shape analysis algorithms implemented digital signal processor. The tool can be used to simulate the detector's response for all the gamma rays and beta particles emitted from (135)Xe, (133m)Xe, (133)Xe, (131m)Xe and (214)Pb. Two- and three-dimensional beta-gamma coincidence spectra from the PhosWatch detector can be produced using the simulation tool. The accurately simulated spectra could be used to calculate system coincidence detection efficiency for each xenon isotope, the corrections for the interference from the various spectral components from radon and xenon isotopes, and system gain calibration. Also, it can generate two- and three-dimensional xenon reference spectra to test beta-gamma coincidence spectral deconvolution analysis software. PMID:19647444

Mekarski, P; Zhang, W; Ungar, K; Bean, M; Korpach, E

2009-07-18

291

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

Microsoft Academic Search

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

Zhu Ji; K. J. Ray Liu

2006-01-01

292

A Decision-Theoretic Framework for Opportunistic Spectrum Access  

Microsoft Academic Search

Built on a hierarchical access structure with primary and secondary users, opportunistic spectrum access improves spectrum efficiency while maintaining compatibility with legacy wireless systems. The basic idea is to allow secondary users to exploit instantaneous spectrum availability while limiting the interference to primary users. In this article, we identify basic components, fundamental trade-offs, and practical constraints in opportunistic spectrum access.

Qing Zhao; Ananthram Swami

2007-01-01

293

A simple replacment for the drift spectrum  

Microsoft Academic Search

The elastic drift spectrum displays, as a function of period, the story drift (expressed as the ratio of the story drift to story height) that a ground motion record would cause in a multistory framed building. It is a pivotal instrument for performance-based earthquake engineering. Wave theory for a uniform shear beam is utilized for calculating this spectrum, but it

P Gülkan; S Akkar

2002-01-01

294

DYNAMIC SPECTRUM ACCESS ASSESSMENT IN COGNITIVE RADIOS  

Microsoft Academic Search

The opportunistic utilization of unused spectrum provides Cognitive Radios (CR) with great performance improvements and enables new applications and services. This Dynamic Spectrum Access (DSA) behavior, however, introduces sev- eral challenges that must be overcome before CR technology can be widely deployed. One of these problems is the assessment of DSA compliance with regulations and policies. Traditional techniques used to

Carlos R. Aguayo Gonzalez; Jeffrey H. Reed

2007-01-01

295

[A method for measuring emission spectrum of YAG phosphor used in LED white light under practical conditions].  

PubMed

A new method for measuring the emission spectra of the YAG phosphor under blue light excitation was proposed. Utilizing the Gaussian function and Fermi function fitting and simulated annealing optimization techniques, mathematical fitting functions for matching mixed emission spectrum were obtained. And so, the emission spectrum of the YAG phosphor was separated, further its luminescence properties can be characterized. Our experiment results proved that its characteristic parameters present non-negligible differences. The optical metric differences such as those in quantum efficiency, light emitting efficiency and energy efficiency are higher than 1%. The difference in CCT (correlated color temperature) is up to tens of K, and chromaticity indicators also produce differences in chromaticity coordinates, dominant wavelength and color purity. But little change is there in the half-peak bandwidth, and peak wavelength is basically unaffected. All these show that the established method can improve the measurement accuracy of YAG yellow phosphor emission spectrum under practical conditions. PMID:24059185

Xu, Yan-Fang; Zhang, Guo-Sheng; Li, Lu-Hai; Ding, Ying-Kun

2013-07-01

296

Microlens diffusers for efficient laser speckle generation.  

PubMed

Laser Speckle is the optical phenomena resulting from the random interference of coherent light. This phenomenon can be utilized to measure the Modulation Transfer Function (MTF) of detector arrays. Common devices used for speckle generation, such as integrating spheres and ground glass, suffer from low efficiencies less than 20%. Microlens diffusers are shown to be more efficient alternatives for speckle generation. An analysis of the statistical behavior of microlens diffusers is presented with emphasis on their application to MTF testing of detector arrays in the visible spectrum. PMID:19550737

Ducharme, Alfred D

2007-10-29

297

A cognitive approach to spectrum sensing in virtual unlicensed wireless network  

Microsoft Academic Search

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 necessitate a new communication paradigm to exploit

Sunita S. Barve; S. B. Deosarkar; Sonal A. Bhople

2009-01-01

298

Evaluation of Efficiency of Capital Sources Utilization and Company Performance of E-Life Mall in Kaohsiung City Based on Data Envelopment Analysis  

Microsoft Academic Search

Our study is based on 20 direct stores of E-Life Mall in Kaohsiung City, Taiwan. After having interviews with 5 store managers of E-Life Mall, we come up with 3 input and 3 output efficiency indices, and apply Data Envelopment Analysis (DEA) to evaluate the performance efficiency of individual store, we also make use of Tobit regression analysis to investigate

Jung-Fang Chen; Pei-Yu Hsieh; Hsi-Wen Chen

2010-01-01

299

A comparative study of the effects of white sugar, unrefined sugar and starch on the efficiency of food utilization and thermogenesis1'2  

Microsoft Academic Search

Energy balance studies withweanlingrats and mice were carried out to investigate the chronic effects of diets containing white sugar, unrefined sugar, and starch as sole carbohydrate on body composition and energetic efficiency. The results show no significant differences in energetic efficiency and in body composition of both rats and mice fed the different carbohydrate diets. However, there is a tendency

AG Dulloo; OA Eisa; DS Miller; J Yudkin

300

Compromised factor-dependent transcription termination in a nusA mutant of Escherichia coli: spectrum of termination efficiencies generated by perturbations of Rho, NusG, NusA, and H-NS family proteins.  

PubMed

The proteins NusA and NusG, which are essential for the viability of wild-type Escherichia coli, participate in various postinitiation steps of transcription including elongation, antitermination, and termination. NusG is required, along with the essential Rho protein, for factor-dependent transcription termination (also referred to as polarity), but the role of NusA is less clear, with conflicting reports that it both promotes and inhibits the process. In this study, we found that a recessive missense nusA mutant [nusA(R258C)] exhibits a transcription termination-defective (that is, polarity-relieved) phenotype, much like missense mutants in rho or nusG, but is unaffected for either the rate of transcription elongation or antitermination in ? phage. Various combinations of the rho, nusG, and nusA mutations were synthetically lethal, and the lethality was suppressed by expression of the N-terminal half of nucleoid protein H-NS. Our results suggest that NusA function is indeed needed for factor-dependent transcription termination and that an entire spectrum of termination efficiencies can be generated by perturbations of the Rho, NusG, NusA, and H-NS family of proteins, with the corresponding phenotypes extending from polarity through polarity relief to lethality. PMID:21602355

Saxena, Shivalika; Gowrishankar, J

2011-05-20

301

Basic amino acid residues in the V3 loop of simian immunodeficiency virus envelope alter viral coreceptor tropism and infectivity but do not allow efficient utilization of CXCR4 as entry cofactor.  

PubMed

In contrast to human immunodeficiency viruses type 1 and type 2 (HIV-1 and HIV-2, respectively), simian immunodeficiency virus (SIVmac) rarely uses CXCR4 (X4) for efficient entry into target cells. Basic amino acid residues in the V3 loop of HIV Env allow efficient coreceptor utilization of X4. Therefore, we investigated if similar changes in the SIVmac Env protein also mediate a coreceptor switch from CCR5 (R5) to X4. Functional analysis revealed that none of eight SIVmac variants, containing V3 regions with an overall charge between +4 and +10, efficiently utilized X4 as entry cofactor. Nonetheless, these alterations had differential effects on SIV coreceptor tropism and on Env expression levels. A single amino acid substitution of L328R, located near the tip of the V3 loop, resulted in grossly reduced Env expression levels and impaired viral infectivity. Notably, additional basic residues restored efficient Env expression and virion incorporation but not infectivity. In comparison to the L328R mutation, changes of P334K and D337K had little disruptive effects on SIVmac entry and replication. Interestingly, mutation of L320K and P321R disrupted coreceptor usage of GPR15 but not R5. These changes also impaired SIVmac replication in peripheral blood mononuclear cells (PBMC) derived from a Delta32/Delta32 donor but not in R5-expressing human or simian PBMC. Our results show that positively charged amino acid residues in the V3 loop affect SIVmac coreceptor tropism and infectivity but do not allow efficient utilization of X4. PMID:11384227

Meister, S; Otto, C; Papkalla, A; Krumbiegel, M; Pöhlmann, S; Kirchhoff, F

2001-06-01

302

Hybrid spread spectrum radio system  

DOEpatents

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.

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

2010-02-02

303

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

SciTech Connect

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.

Vladimir Bulovic and Moungi Bawendi

2011-09-30

304

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...

305

Genome Sequence of Enterobacter cloacae subsp. dissolvens SDM, an Efficient Biomass-Utilizing Producer of Platform Chemical 2,3-Butanediol  

PubMed Central

Enterobacter cloacae subsp. dissolvens SDM has an extraordinary characteristic of biomass utilization for 2,3-butanediol production. Here we present a 4.9-Mb assembly of its genome. The key genes for regulation and metabolism of 2,3-butanediol production were annotated, which could provide further insights into the molecular mechanism of high-yield production of 2,3-butanediol.

Xu, Youqiang; Wang, Ailong; Tao, Fei; Su, Fei; Tang, Hongzhi

2012-01-01

306

Modelling Cost Effectiveness and Cost Utility of Sequential DMARD Therapy Including Leflunomide for Rheumatoid Arthritis in Germany: II. The Contribution of Leflunomide to Efficiency  

Microsoft Academic Search

Objective: To estimate the 3-year incremental cost effectiveness and cost utility of introducing leflunomide into sequential therapy, consisting of the most frequently used disease-modifying antirheumatic drugs (DMARDs), for patients with rheumatoid arthritis in specialised, i.e. rheumatological, care in Germany. Design and setting: The analysis was conducted from the societal perspective in Germany using an existing 3-year simulation model, which was

Peter K. Schadlich; Henning Zeidler; Angela Zink; Erika Gromnica-Ihle; Matthias Schneider; Christoph Straub; Josef G. Brecht; Eduard Huppertz

2005-01-01

307

Efficient utilization and operation of the gluconate-inducible system of the promoter of the Bacillus subtilis gnt operon in Escherichia coli.  

PubMed Central

A DNA fragment containing the promoter of the Bacillus subtilis gluconate (gnt) operon and its first gene (gntR) was cloned into Escherichia coli. E. coli recognized this promoter efficiently and precisely. Moreover, the gluconate-inducible system of this operon operated even in E. coli. Images

Miwa, Y; Fujita, Y

1987-01-01

308

Computationally Efficient Approaches to Characterize the Dynamic Response of Microstructures Under Mechanical Shock  

Microsoft Academic Search

We present computationally efficient models and approaches to simulate the response of microstructures under mechanical shock. These approaches include a Galerkin-based reduced-order model and a hybrid approach utilizing the response of structures to static loads combined with the dynamic shock spectrum of a spring-mass-damper system. To demonstrate the accuracy and efficiency of these approaches, we apply them on cantilever and

Mohammad I. Younis; Daniel Jordy; James M. Pitarresi

2007-01-01

309

High-efficiency organic light-emitting diodes utilizing thermally activated delayed fluorescence from triazine-based donor-acceptor hybrid molecules  

NASA Astrophysics Data System (ADS)

We have designed and synthesized a high-efficiency purely organic luminescent material, 2,4-bis{3-(9 H-carbazol-9-yl)-9 H-carbazol-9-yl}-6-phenyl-1,3,5-triazine (CC2TA) comprising the bicarbazole donor and phenyltriazine acceptor units, which is capable of emitting thermally activated delayed fluorescence. The molecular design of CC2TA allows spatial separation of HOMO and LUMO on the donor and acceptor fragments, respectively, leading to an exceptionally small singlet-triplet exchange energy (?EST = 0.06 eV) together with a high triplet energy. Furthermore, a high external electroluminescence quantum efficiency as high as 11% +/- 1% has been achieved in the sky-blue organic light-emitting diodes employing CC2TA as an emitter.

Youn Lee, Sae; Yasuda, Takuma; Nomura, Hiroko; Adachi, Chihaya

2012-08-01

310

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

DOEpatents

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.

Beach, R.J.

1997-11-18

311

Nitrogen indicators, uptake and utilization efficiency in a maize and barley rotation cropped at different levels and sources of N fertilization  

Microsoft Academic Search

A 3-year experiment was carried out in Mediterranean conditions on two maize–barley rotations to determine the effect of different levels and sources of nitrogen (N) fertilizer on the N uptake, efficiency, soil N deficit and crops yield. The potential for N savings by the use of N indicators was also studied.Five strategies of maize N fertilization were compared on plots

F. Montemurro; M. Maiorana; D. Ferri; G. Convertini

2006-01-01

312

Efficiency of nitrogen and phosphorus utilization in progenies of factorial crosses between European and exotic cultivars of spring barley ( Hordeum vulgare L.)  

Microsoft Academic Search

Previous observations suggested that some landraces, primitive cultivars and other barleys originating from the harsh conditions\\u000a of the Middle East, North Africa and Tibet might serve as interesting sources of adaptation to low-input agriculture. This\\u000a opportunity was verified in field experiments performed under reduced rates of nitrogen (N) and phosphorus (P) fertilization.\\u000a Genetic variation in major components of the efficiency

Andrzej G. Górny; Dominika Ratajczak

2008-01-01

313

Bacterial Activity and Bacterioplankton Diversity in the Eutrophic River Warnow—Direct Measurement of Bacterial Growth Efficiency and Its Effect on Carbon Utilization  

Microsoft Academic Search

The influence of bacterial activity and diversity on bacterial growth efficiency was investigated in a flatland river. Eutrophic\\u000a River Warnow drains predominantly agricultural land and is heavily loaded with nutrients, dissolved and particulate organic\\u000a matter (DOM and POM), especially humic substances. Although the water column bacterial community consists of many inactive\\u000a or damaged cells, bacterioplankton sustained a high bacterial secondary

Mareike Warkentin; Heike M. Freese; Rhena Schumann

2011-01-01

314

COOLCEP (cool clean efficient power): A novel CO 2-capturing oxy-fuel power system with LNG (liquefied natural gas) coldness energy utilization  

Microsoft Academic Search

A novel liquefied natural gas (LNG) fueled power plant is proposed, which has virtually zero CO2 and other emissions and a high efficiency. The plant operates as a subcritical CO2 Rankine-like cycle. Beside the power generation, the system provides refrigeration in the CO2 subcritical evaporation process, thus it is a cogeneration system with two valued products. By coupling with the

Na Zhang; Noam Lior; Meng Liu; Wei Han

2010-01-01

315

Spectrum of Care  

MedlinePLUS

... up? Login here Please leave this field empty Spectrum of Care SHARE Share on Facebook Preview your ... Share Cancel Close Finish Home > Care and Treatment > Spectrum of Care Listen The Continuum of Care After ...

316

The Electromagnetic Spectrum  

NSDL National Science Digital Library

This web site contains materials about all parts of the electromagnetic spectrum. It describes each space telescope that NASA has launched as well as its observing range in the electromagnetic spectrum.

Astrophysics, Laboratory F.

2004-11-17

317

Utilization of the PC for analysis of gamma-ray spectra for reactor applications  

Microsoft Academic Search

A computer program has been developed for using the IBM PC and PC compatibles for gamma-ray spectrum analysis, including computation of photopeak areas from high-resolution spectra, identification of radioisotopes, and computation of absolute activity, based on absolute detector efficiency calibration. The program utilizes the direct transfer of gamma-ray spectra from any multichannel pulse-height analyzer with RS-232 serial output into the

George W

1986-01-01

318

Food utilization efficiency in fifth instar larvae of Antheraea mylitta (Lepidoptera: Saturniidae) infected with Nosema sp. and its effect on reproductive potential and silk production.  

PubMed

Antheraea mylitta, a sericigenous insect of economical importance is often infected with an intracellular parasite of the genus Nosema. This pathogen is known to cause fatal pebrine disease and is considered as an important factor that strongly influences the development of the host. Larvae developed from the eggs laid by a female infected with Nosema sp. showed extended development period. The increment in the larval weight declined significantly in infected larvae in comparison to uninfected ones. Food consumption, digestion, relative consumption rate (RCR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), and relative growth rate (RGR) values declined significantly, but at the same time a significant increase in approximate digestibility (AD) was also observed. Silk production declined in infected larvae. Silk gland weight and shell weight also significantly declined following infection over uninfected larvae. The reproductive potential in adults declined significantly (P<0.001) with decrease in ovary weight (31.6%), fecundity (54.1%), and fertility (34.9%). Egg chorionation was also affected in adults, which developed from infected larvae. The maternal infection level in one generation (10.4 x 10(6) spores/female) decreased significantly in the next generation (8.0 x 10(6) spores/female). PMID:12725805

Rath, S S; Prasad, B C; Sinha, B R R P

2003-05-01

319

Synthesis of accelerograms compatible with the Chinese GB 50011-2001 design spectrum via harmonic wavelets: artificial and historic records  

NASA Astrophysics Data System (ADS)

A versatile approach is employed to generate artificial accelerograms which satisfy the compatibility criteria prescribed by the Chinese aseismic code provisions GB 50011-2001. In particular, a frequency dependent peak factor derived by means of appropriate Monte Carlo analyses is introduced to relate the GB 50011-2001 design spectrum to a parametrically defined evolutionary power spectrum (EPS). Special attention is given to the definition of the frequency content of the EPS in order to accommodate the mathematical form of the aforementioned design spectrum. Further, a one-to-one relationship is established between the parameter controlling the time-varying intensity of the EPS and the effective strong ground motion duration. Subsequently, an efficient auto-regressive moving-average (ARMA) filtering technique is utilized to generate ensembles of non-stationary artificial accelerograms whose average response spectrum is in a close agreement with the considered design spectrum. Furthermore, a harmonic wavelet based iterative scheme is adopted to modify these artificial signals so that a close matching of the signals’ response spectra with the GB 50011-2001 design spectrum is achieved on an individual basis. This is also done for field recorded accelerograms pertaining to the May, 2008 Wenchuan seismic event. In the process, zero-phase high-pass filtering is performed to accomplish proper baseline correction of the acquired spectrum compatible artificial and field accelerograms. Numerical results are given in a tabulated format to expedite their use in practice.

Spanos, P. D.; Giaralis, A.; Li, Jie

2009-06-01

320

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

SciTech Connect

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.

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

1993-04-01

321

Methodological Innovation to Increase the Utility and Efficiency of Psychotherapy Research for Patients with Co-occurring Mental Health and Substance Use Disorders  

PubMed Central

Psychotherapy research with chronic and difficult-to-treat populations such as those with co-occurring mental health and addictive disorders can employ flexible research designs, which allow for a systematic, yet non-linear relationship between efficacy and effectiveness designs. Outcomes research can bypass the efficacy-effectiveness dichotomy through use of a hybrid model (Carroll & Rounsaville, 2003) conducted in the context of community treatment settings in collaboration with community providers. We present the case for using this methodological approach as a means of advancing psychotherapy research and practice, while translating and disseminating empirically supported treatments with more efficiency. A hybrid model study conducted within the National Institute on Drug Abuse’s Clinical Trials Network illustrates the application. These findings inform new directions for future research.

Hien, Denise A.; Cohen, Lisa R.; Campbell, Aimee N. C.

2009-01-01

322

High-efficiency, one-step starch utilization by transformed Saccharomyces cells which secrete both yeast glucoamylase and mouse alpha-amylase.  

PubMed Central

Transformed, hybrid Saccharomyces strains capable of simultaneous secretion of glucoamylase and alpha-amylase have been produced. These strains could carry out direct, one-step assimilation of starch, with conversion efficiency greater than 93% during a 5-day growth period. One of the transformants converted 92.8% of available starch into reducing sugars in only 2 days. Glucoamylase secretion by these strains resulted from expression of one or more chromosomal STA genes derived from Saccharomyces diastaticus. The strains were transformed by a plasmid (pMS12) containing mouse salivary alpha-amylase cDNA in an expression vector containing yeast alcohol dehydrogenase promoter and a segment of yeast 2 micron plasmid. The major starch hydrolysis product produced by crude amylases found in culture broths was glucose, indicating that alpha-amylase and glucoamylase acted cooperatively.

Kim, K; Park, C S; Mattoon, J R

1988-01-01

323

Coal utilization  

SciTech Connect

This paper overviews coal utilization in the U.S. Electric utilities are by far the largest consumers of coal produced in the United States. In 1988, US utilities purchased about 690 Mt (760 million st). This represented 78% of total domestic coal production. Many coalfields are mined solely for the utility market. Many western coalfields are owned by utilities, generally through subsidiaries or joint ventures. Coal-fired generation is the backbone of the utility industry. It accounted for more than 1.5 billion (57%) of the 2.7 billion kW-hr generated in 1988. The tie between coal producers and consumers is underscored by the fuel bill. Utilities spent $23 billion for coal in 1988. That represented 80% of the operations and maintenance cost of coal-fired generation.

O'Conner, D. (Electric Power Research Inst., Palo Alto, CA (USA)); Harrison, C.D. (CQ Inc. (US))

1990-06-01

324

Efficient 13C/15N double labeling of the avirulence protein AVR4 in a methanol-utilizing strain (Mut+) of Pichia pastoris.  

PubMed

Cost effective 13C/15N-isotope labeling of the avirulence protein AVR4 (10 kDa) of the fungal tomato pathogen Cladosporium fulvum was achieved with the methylotrophic yeast Pichia pastoris in a fermentor. The 13C/15N-labeled AVR4 protein accumulated to 30 mg/L within 48 h in an initial fermentation volume of only 300 mL, while prolonged optimized overexpressions yielded 126 mg/L. These protein yields were 24-fold higher in a fermentor than in flask cultures. In order to achieve these protein expression levels, we used the methanol-utilizing strain (Mut+) of Pichia pastoris which has a high growth rate while growing on methanol as the only carbon source. In contrast, the methanol-sensitive strain (MutS) could intrinsically yield comparable protein expression levels, but at the expense of additional carbon sources. Although both strains are generally used for heterologous protein expression, we show that the costs for 13C-isotope labeling can be substantially reduced using the Mut+ strain compared to the MutS strain, as no 13C3-glycerol is required during the methanol-induction phase. Finally, nitrogen limitations were precluded for 15N-labeling by an optimal supply of 10 g/L (15NH4)2SO4 every 24 h. PMID:11519748

van den Burg, H A; de Wit, P J; Vervoort, J

2001-07-01

325

Utility of a novel multiplex TaqMan PCR assay for metallo-?-lactamase genes plus other TaqMan assays in detecting genes encoding serine carbapenemases and clinically significant extended-spectrum ?-lactamases.  

PubMed

Prompt detection of infections caused by Enterobacteriaceae that produce therapeutically important ?-lactamases [metallo-?-lactamases (MBLs), serine carbapenemases, acquired AmpC and CTX-M extended-spectrum ?-lactamases (ESBLs)] is crucial for infection prevention and control and surveillance purposes, and, more contentiously, also for effective patient management. A novel TaqMan PCR assay was developed to detect genes encoding IMP, VIM, NDM, SPM, SIM and GIM MBLs. Published PCR assays for acquired genes encoding CTX-M ESBLs and AmpC ?-lactamases were updated and adapted to the TaqMan format, respectively. A published TaqMan assay for serine carbapenemase genes was used. Assay specificity was tested using a panel of 59 isolates with known acquired genes from the four different ?-lactamase groupings. The four TaqMan assays correctly identified the most clinically relevant acquired ?-lactamase genes in the panel of 59 resistant Enterobacteriaceae, which included 3 VIM-, 7 NDM- and 12 IMP-producers. Consecutive, non-duplicate isolates of Enterobacteriaceae from 965 urinary and 343 blood cultures during 2010 were then screened for ?-lactamase genes using these TaqMan assays. Amongst the urinary and blood culture isolates tested, 69 CTX-M-producers and 21 acquired AmpC ?-lactamase-producers were identified; the CTX-M rate amongst blood culture isolates (9.3%) broadly reflects the UK national average. During the study period, one Klebsiella pneumoniae isolate producing an NDM carbapenemase was identified from a wound sample. The assays developed and/or used will enable the future surveillance and the rapid detection and appropriate early treatment of infections caused by Gram-negative bacteria producing clinically important ?-lactamases, including carbapenemases. PMID:23988718

Swayne, Rosemary; Ellington, Matthew J; Curran, Martin D; Woodford, Neil; Aliyu, Sani H

2013-08-09

326

Investigation of a method of enhancing the efficiency of difference frequency generation by stimulated Raman scattering utilizing an inhomogeneous electrostatic field  

NASA Astrophysics Data System (ADS)

An investigation is made of resonance parametric difference-frequency generation by stimulated Raman scattering (STRS) in the presence of a periodically inhomogeneous electrostatic field (externally applied or internal field). The initial and maximum difference-frequency generation intensities are determined for arbitrary relationships between the parameters of the system (difference-frequency absorption coefficient and gain of the STRS Stokes component, wave mismatch, and period of the periodically inhomogeneous electrostatic field). It is found that by generating a periodically inhomogeneous electrostatic field, it is possible to compensate for the decrease in the difference-frequency generation efficiency not only due to the wave mismatch but also due to parametric bleaching. Conditions under which the improvement in the intensity of the difference frequency generation is several orders of magnitude are discussed. By using a periodically inhomogeneous electrostatic field applied to compressed H2, an improvement by a factor of 20-80 was obtained for pumping at ?? = 1.06? and by a factor of gtrsim 100 for pumping at ?? = 0.694 ?, in agreement with the estimates obtained using the equations derived in the present paper.

Butylkin, V. S.; Fisher, P. S.; Shalyaev, M. F.

1980-02-01

327

Full spectrum broken cloud scene simulation  

NASA Astrophysics Data System (ADS)

This paper discusses the effects of broken cloud fields on solar illumination reaching the ground. Application of aerosol retrieval techniques in the vicinity of broken clouds leads to significant over prediction of aerosol optical depth because of the enhancement of visible illumination from the scattering of photons from clouds into clear patches. These illumination enhancement effects are simulated for a variety of broken cloud fields using the MCScene code, a high fidelity model for full optical spectrum (UV through LWIR) spectral image simulation. MCScene provides an accurate, robust, and efficient means to generate spectral scenes for algorithm validation. MCScene utilizes a Direct Simulation Monte Carlo approach for modeling 3D atmospheric radiative transfer (RT), including full treatment of molecular absorption and Rayleigh scattering, aerosol absorption and scattering, and multiple scattering and adjacency effects, as well as scattering from spatially inhomogeneous surfaces. The model includes treatment of land and ocean surfaces, 3D terrain, 3D surface objects, and effects of finite clouds with surface shadowing. The paper includes an overview of the MCScene code and a series of calculations for broken 3D cloud fields demonstrating the effects of clouds on downwelling flux.

Richtsmeier, Steven; Sundberg, Robert

2009-09-01

328

YEAR 2 BIOMASS UTILIZATION  

SciTech Connect

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

Christopher J. Zygarlicke

2004-11-01

329

Quantum Spread Spectrum Communication  

SciTech Connect

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.

Humble, Travis S [ORNL

2011-01-01

330

Tailored Communication to Enhance Adaptation across the Breast Cancer Spectrum.  

National Technical Information Service (NTIS)

Breast cancer represents a serious health concern for women across the disease spectrum. First, despite the advances in technology used for intensive disease surveillance and innovative preventative options, interest in and utilization of these technologi...

S. M. Miller

2004-01-01

331

Increased Photovoltaic Power Output via Diffractive Spectrum Separation  

NASA Astrophysics Data System (ADS)

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.

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

2013-03-01

332

Dynamic Spectrum Access with QoS and Interference Temperature Constraints  

Microsoft Academic Search

Spectrum is one of the most precious radio resources. With the increasing demand for wireless communication, efficiently using the spectrum resource has become an essential issue. With the Federal Communications Commission's (FCC) spectrum policy reform, secondary spectrum sharing has gained increasing interest. One of the policy reforms introduces the concept of an interference temperature—the total allowable interference in a spectral

Yiping Xing; Chetan Nanjunda Mathur; Mohamed A. Haleem; Rajarathnam Chandramouli; K. P. Subbalakshmi

2007-01-01

333

ITO-Schottky photodiodes for high-performance detection in the UV-IR spectrum  

Microsoft Academic Search

High-performance vertically illuminated Schottky photodiodes with indium-tin-oxide (ITO) Schottky layers were designed, fabricated, and tested. Ternary and quarternary III-V material systems (AlGaN-GaN, AlGaAs-GaAs, InAlGaAs-InP, and InGaAsP-InP) were utilized for detection in the ultraviolet (UV) (?<400 nm), near-IR (??850 nm), and IR (??1550 nm) spectrum. The material properties of thin ITO films were characterized. Using resonant-cavity-enhanced (RCE) detector structures, improved efficiency

Necmi Biyikli; Ibrahim Kimukin; Bayram Butun; Orhan Aytür; Ekmel Ozbay

2004-01-01

334

Spread spectrum microwave bistatic intrusion detection sensor performance update  

SciTech Connect

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''.

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

1986-01-01

335

Hybrid Spectrum Sensing Architecture for Cognitive Radio Equipment  

Microsoft Academic Search

Spectrum sensing is the key function in implementing cognitive radio, which enables secondary users to identify and utilize vacant spectrum resource allocated to primary users. Recent studies have proposed four major sensing methods, including matched filter, energy, feature, and eigenvalue-based detectors. However, there are some drawbacks along with them. In this paper, we propose a hybrid architecture, associating energy and

Ziad Khalaf; Amor Nafkha; Jacques Palicot; Mohamed Ghozzi

2010-01-01

336

Frequency Spectrum Availability.  

National Technical Information Service (NTIS)

The purpose of the report is to review the electromagnetic spectrum indicating which bands might be available for urban vehicle location/communication(L/C) services. The spectrum is divided into 'services' so that there is some choice concerning the categ...

1969-01-01

337

Fetal Alcohol Spectrum Disorder  

ERIC Educational Resources Information Center

|Fetal alcohol spectrum disorder (FASD) is a serious and widespread problem in this country. Positioned within the community with links to children, families, and healthcare systems, school nurses are a critical element in the prevention and treatment of those affected by fetal alcohol spectrum disorder. Although most school nurses are familiar…

Caley, Linda M.; Kramer, Charlotte; Robinson, Luther K.

2005-01-01

338

Fetal Alcohol Spectrum Disorder  

ERIC Educational Resources Information Center

Fetal alcohol spectrum disorder (FASD) is a serious and widespread problem in this country. Positioned within the community with links to children, families, and healthcare systems, school nurses are a critical element in the prevention and treatment of those affected by fetal alcohol spectrum disorder. Although most school nurses are familiar…

Caley, Linda M.; Kramer, Charlotte; Robinson, Luther K.

2005-01-01

339

The CMBR spectrum  

SciTech Connect

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.

Stebbins, A.

1997-05-01

340

The Electromagnetic Spectrum  

NSDL National Science Digital Library

This tutorial introduces students to the concepts of electromagnetic waves, wavelength, and the electromagnetic spectrum. Diagrams and written descriptions explain how wavelength is measured and explore the traditional divisions of the spectrum: radio, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

341

Autism spectrum disorders  

Microsoft Academic Search

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

Tony Charman

2008-01-01

342

Sharing Spectrum through Spectrum Policy Reform and Cognitive Radio  

Microsoft Academic Search

Traditionally, interference protection is guaranteed through a policy of spectrum licensing, whereby wireless systems get exclusive access to spectrum. This is an effective way to prevent interference, but it leads to highly inefficient use of spectrum. Cognitive radio along with software radio, spectrum sensors, mesh networks, and other emerging technologies can facilitate new forms of spectrum sharing that would greatly

Jon M. Peha

2008-01-01

343

Making energy efficiency happen  

NASA Astrophysics Data System (ADS)

Improving energy efficiency is the least expensive and most effective way to address simultaneously several national issues. Improving efficiency saves money for consumers, increases economic productivity and international competitiveness, enhances national security by lowering oil imports, and reduces the adverse environmental effects of energy production. This paper discusses some of the many opportunities to improve efficiency, emphasizing the roles of government and utilities.

Hirst, E.

1991-04-01

344

On the ice nucleation spectrum  

NASA Astrophysics Data System (ADS)

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.

Barahona, D.

2011-11-01

345

Physical Interference Driven Dynamic Spectrum Management  

Microsoft Academic Search

Dynamic spectrum management can drastically im- prove the performance of wireless networks struggling under increasing user demands. However, performing efficient spe ctrum allocation is a complex and difficult process. Current propo sals make the problem tractable by simplifying interference con- straints as conflict graphs, but they face potential perform ance degradation from inaccurate interference estimation. In this paper, we show

Lei Yang; Lili Cao; Heather Zheng

2008-01-01

346

The FCC Spectrum Auctions: An Early Assessment  

Microsoft Academic Search

This paper analyzes six spectrum auctions conducted by the Federal Communications Commission from July 1994 to May 1996. These auctions were simultaneous multiple-round auctions in which collections of licenses were auctioned simultaneously. This auction form proved remarkably successful. Similar items sold for similar prices, and bidders successfully formed efficient aggregations of licenses. Bidding behavior differed substantially in the auctions. The

Peter C. Cramton

1997-01-01

347

A Comprehensive Book on Autism Spectrum Disorders  

ERIC Educational Resources Information Center

|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…

Mohammadi, Mohammad-Reza, Ed.

2011-01-01

348

Spread spectrum for commercial communications  

Microsoft Academic Search

The authors describe how spread spectrum operates and explain why the FCC has allocated several spectral bands for spread spectrum. They examine what is wrong with the spectrum allocations the way they are now. They show who is using and will use spread spectrum and why. In particular, they discuss the use of spread spectrum for mobile cellular communications: the

D. L. Schilling; L. B. Milstein; R. L. Pickholtz; M. Kullback; F. Miller

1991-01-01

349

Blackbody Radiation Spectrum Model  

NSDL National Science Digital Library

The Blackbody Radiation Spectrum model shows six fixed-temperature curves between Tmin and Tmax and a red variable-temperature curve that can be adjusted using a slider. The wavelength is measured in nm (nanometer) and the intensity is measured in W.e-5 / (m2.nm). Users can adjust Tmin and Tmax to change the temperature range that is displayed. The Blackbody Radiation Spectrum was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double click the ejs_ntnu_BlackbodyRadiationSpectrum.jar file to run the program if Java is installed.

Hwang, Fu-Kwun

2009-08-22

350

Towards the efficient utilization of geothermal resources  

Microsoft Academic Search

Separated geothermal water from production wells at Wairakei, Ohaaki, Kawerau, Ngawha, and other less developed fields in New Zealand, contains potentially valuable chemical constituent. In particular, the extraction of precipitated amorphous silica is discussed in terms of its strategic and beneficial value to expanded energy generation in geothermal development, removal of environmentally sensitive constituents and as a marketable commodity in

R. T. Harper; I. A. Thain; J. H. Johnston

2009-01-01

351

Electric utility forecasting of customer cogeneration and the influence of special rates. Final report  

SciTech Connect

Cogeneration, or the simultaneous production of heat and electric or mechanical power, emerged as one of the main components of the energy conservation strategies in the past decade. Special tax treatment, exemptions from fuel use restrictions, and regulatory policy changes were crafted to encourage its more wide-spread adoption in anticipation of higher energy conversion efficiencies. The expansion of cogeneration still faces a broad spectrum of problems, current and future: environmental restrictions; capital constraints; fuel prices; utility rates and future utility economics; and the difficulties of management. The most debated issue has been the reform of rates between individual cogenerators and the local electric utility. Many of the major cogeneration studies in the late 1970's urged an analysis of the exact impact from current electric utility rates upon cogeneration project economics. The changes mandated by the Public Utilities Regulatory Policy Act of 1978 (PURPA) are now reaching the final implementation stage and the cogeneration projects of the mid 1970s are nearing completion. To better understand the relationship between utility rates, the economics of cogeneration, and its potential development, the New England Electric System and the Massachusetts Institute of Technology Energy Laboratory Utility Systems Group began a study to refine methods for forecasting cogeneration in a specific utility service area with special attention devoted to the utility rates.

Pickel, F.H.

1981-03-01

352

Fetal Alcohol Spectrum Disorders  

MedlinePLUS

... are pregnant. Drinking alcohol can cause a group of conditions called fetal alcohol spectrum disorders (FASDs).Effects can include physical and behavioral problems such as trouble with Learning ...

353

The Electromagnetic Spectrum: FRONTLINE  

NSDL National Science Digital Library

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.

Foundation, Wgbh E.

2004-02-20

354

Spectrum Transformation for Divergent Iterations.  

National Technical Information Service (NTIS)

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 t...

M. M. Gupta

1991-01-01

355

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

NASA Astrophysics Data System (ADS)

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.

Kavehrad, M.

2013-01-01

356

The research of optical fiber Brillouin spectrum denoising based on wavelet transform and neural network  

NASA Astrophysics Data System (ADS)

The center frequency of Brillouin scattering spectrum is easily influenced by the noise and the measurement accuracy of optical fiber strain is reduced. So a novel denoising method which can be applied in the Brillouin scattering spectrum is developed in this article. The Brillouin scattering spectrum is decomposed into multi-scale detail coefficients and approximation coefficients by using the wavelet transform. The wavelet decomposition detail coefficients are threshold quantified by utilizing the threshold algorithm. At the same time, the wavelet decomposition approximation coefficients are trained and simulated by using the BP neural network in order to remove noise hided in the approximation coefficients. So the novel method can reduce the wavelet decomposition scales. The Brillouin scattering spectrum which has a better denoising effect can be gained by using the inverse wavelet transform, and the measurement accuracy of optical fiber strain is enhanced also. The results of simulation and experiment demonstrate that the proposed method can suppress noise better; accordingly, the new method can gain more precision optical fiber strain and reduce the wavelet decomposition scales effectively than the conventional wavelet denoising method. Theory analysis and experiment show that the method is reasonable and efficient.

Zhang, Zhi-hui; Hu, Wei-liang; Yan, Ji-song; Zhang, Peng

2013-08-01

357

Orbit utilization - Current regulations  

NASA Astrophysics Data System (ADS)

It is pointed out that an increasingly efficient use of the geostationary satellite orbit and spectrum is necessary to accommodate the growing number of planned U.S. domestic satellites, as well as those of other countries. Technical efficiency can be maximized by designing satellites in a homogeneous manner which minimizes transmission differences between satellites. However, flexibility is also needed to design domestic satellite facilities to respond to the diverse demands in a competitive market. The Federal Communication Commission (FCC) seeks to achieve a balance between these goals in their domestic satellite policies and regulations. In December 1980, the FCC authorized the construction of some 22 new domestic satellites and the launch of 18 satellites. Attention is given to orbit use policies and reduced orbital spacings.

Lepkowski, R. J.

358

Glary Utilities  

NSDL National Science Digital Library

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.

2008-01-01

359

Smart radio: spectrum access for first responders  

NASA Astrophysics Data System (ADS)

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.

Silvius, Mark D.; Ge, Feng; Young, Alex; MacKenzie, Allen B.; Bostian, Charles W.

2008-05-01

360

Replacement of Spectrum Sensing and Avoidance of Hidden Terminal for Cognitive Radio  

Microsoft Academic Search

Cognitive radio technique has been recently proposed as a novel approach for improving the utilization of the precious limited radio resources, by letting secondary users access primary users' spectrum if not used. There are two major challenges for cognitive radio: spectrum sensing and hidden terminal problem. In this paper, a novel network structure is proposed to separate the spectrum sensing

Zhu Han; Hai Jiang

2008-01-01

361

Dynamic spectrum access opportunities for public safety in land mobile radio bands  

Microsoft Academic Search

We present the results of a preliminary assessment of the potential for applying Dynamic Spectrum Access (DSA) meth- ods to improve radio frequency spectrum utilization in the land mobile radio (LMR) bands in the U.S. This band includes both public safety and commercial user frequency assignments. First, using RF spectrum measurements made in Chicago, occupancy statistics in the widely used

Tanim M. Taher; Roger B. Bacchus; Kenneth J. Zdunek; Dennis A. Roberson

2011-01-01

362

Japanese utilities` plutonium utilization program  

Microsoft Academic Search

Japan`s 10 utility companies are working and will continue to work towards establishing a fully closed nuclear fuel cycle. The key goals of which are: (1) reprocessing spent fuel; (2) recycling recovered uranium and plutonium; and (3) commercializing fast breeder technology by around the year 2030. This course of action by the Japanese electric power industry is in full accordance

Matsuo; Yuichiro

1996-01-01

363

Strategy Paper on Efficient and Effective Dissemination Plans for the Information Dissemination System of the Department of Energy's Economiic Regulatory Administration, Office of Utility Systems, Division of Rates and Energy Management.  

National Technical Information Service (NTIS)

Section I, the Introduction, concentrates on the purposes of the DOE/DREM bibliographic energy utility data base consisting of research and experimental studies announced publicly in the Electric and Gas Utility Topics: Current Documents brochures. Dissem...

1982-01-01

364

Spectrum of wormholes  

SciTech Connect

Wormholes have been studied mainly in the semiclassical approximation as solutions of the classical Euclidean field equations. However, such solutions are rather special, and exist only for certain kinds of matter. On the other hand, one can represent wormholes in a more general manner as solutions of the Wheeler-DeWitt equation with appropriate boundary conditions. Minisuperspace models with massless minimal or conformal scalar fields have a discrete spectrum of these solutions. The Giddings-Strominger instanton solution corresponds to a sum of an infinite number of these solutions. Minisuperspace models with a massive scalar field also appear to have a discrete spectrum of such solutions, whose asymptotic form is given.

Hawking, S.W. (Institute for Theoretical Physics, University of California, Santa Barbara, CA (USA) Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW (United Kingdom)); Page, D.N. (Institute for Theoretical Physics, University of California, Santa Barbara, CA (USA) Department of Physics, Pennsylvania State University, University Park, PA (USA) Theoretical Physics Institute, Department of Physics, University of Alberta, Edmonton, AB (Canada))

1990-10-15

365

Autism spectrum disorders.  

PubMed

Autism spectrum disorders are being diagnosed with increasing frequency. The likelihood that a primary care provider will see a patient with autism spectrum disorder in their clinic is high. In this article, current diagnostic criteria and expected changes in DSM criteria, as well as prevalence rates and epidemiologic studies are reviewed. Recommendations for screening, including early warning signs, and best practices for diagnosis are discussed. Comprehensive evidence based intervention for ASD as well as the findings of the National Standards Project are reviewed. Medication management is also described, as are the roles of other treating professionals. PMID:23332397

Manning-Courtney, Patricia; Murray, Donna; Currans, Kristn; Johnson, Heather; Bing, Nicole; Kroeger-Geoppinger, Kim; Sorensen, Rena; Bass, Jennifer; Reinhold, Judy; Johnson, Amy; Messerschmidt, Teri

2013-01-01

366

Free-form Fresnel RXI Köhler design with spectrum-splitting for photovoltaics  

NASA Astrophysics Data System (ADS)

Here we present a novel optical design of the high concentration photovoltaics (HPCV) nonimaging concentrator (>500x) with built-in spectrum splitting concept. The primary optical element (POE) is a flat Fresnel lens and the secondary optical element (SOE) is a free-form RXI-type concentrator with a band-pass filter embedded in it, both POE and SOE performing Köhler integration to produce light homogenization on the target. It uses the combination of a commercial concentration GaInP/GaInAs/Ge 3J cell and a concentration Back-Point-Contact (BPC) silicon cell for efficient spectral utilization, and external confinement techniques for recovering the 3J cell's reflection. Design targets equivalent cell efficiency ~46% using commercial 39% 3J and 26% Si cells, and CPV module efficiency greater than 38%, achieved at a concentration level larger than 500X and wide acceptance angle (+/-1°). A first proof-of concept receiver prototype has been manufactured using a simpler optical architecture (with a lower concentration, ~100x and lower simulated added efficiency), and experimental measurements have shown up to 39.8% 4J receiver efficiency using a 3J with peak efficiency of 36.9%.

Buljan, M.; Benítez, P.; Mohedano, R.; Miñano, J. C.; Sun, Y.; Falicoff, W.; Vilaplana, J.; Chaves, J.; Biot, G.; López, J.

2011-09-01

367

Jackknifing Multitaper Spectrum Estimates  

Microsoft Academic Search

This article discusses some examples of jackknifing multitaper estimates of spectra, coherences, and frequency estimates. Examples include barometric pressure data, where spectrum with an extremely large range plus many narrow-band processes are seen. Analysis of dropped-call rates in cellular phone systems and their coherence with solar radio data illustrates further uses of the jackknife and some of the complexities encountered

David J. Thomson; KARL HEINRICH HOFMANN

2007-01-01

368

Understanding autism spectrum disorders  

Microsoft Academic Search

This paper considers a practical overview of the diagnosis and management of autism spectrum disorders, a group of neurodevelopmental disorders typified by childhood autism. It will focus primarily on the presentation of pre-school and school-aged children, as these children often first present to paediatricians in the pathway to care. Reference is made to recent national guidelines for assessment and management,

B Steyn; A. Le Couteur

2003-01-01

369

Fetal Alcohol Spectrum Disorder  

Microsoft Academic Search

Background: Maternal alcohol use during pregnancy leads to fetal alcohol spectrum disorder (FASD) in their children. FASD is characterized by typical facial features, growth retardation, intellectual dysfunction and behavioral problems. Justification: Alcohol is neurotoxic to the brain during the developmental stage. Behavioral problems in children with FASD start at an early age and progress to adulthood. It is an important

RAGHAVENDRA BHEEMAPPA N AYAK; PRATIMA MURTHY

370

Stellar Spectrum Synthesizer  

ERIC Educational Resources Information Center

Describes a device which employs two diffraction gratings and three or four simple lenses to produce arbitrary absorption or emission spectra that may be doppler shifted and spectroscopically examined by students some distance away. It may be regarded as a sort of artificial star whose spectrum may be analyzed as an undergraduate laboratory…

Landegren, G. F.

1975-01-01

371

Stellar Spectrum Synthesizer  

ERIC Educational Resources Information Center

|Describes a device which employs two diffraction gratings and three or four simple lenses to produce arbitrary absorption or emission spectra that may be doppler shifted and spectroscopically examined by students some distance away. It may be regarded as a sort of artificial star whose spectrum may be analyzed as an undergraduate laboratory…

Landegren, G. F.

1975-01-01

372

IR spectrum of cellulose  

Microsoft Academic Search

model the total spectrum in the given region, and the results are compared with the experimental data. The mean square deviation of the fitting contour from the experimental curve is no more than 5%. It is known that the set of properties of the physical structure of cellulose is determined by the possibility of existence of rotamers of hydroxyl and

N. V. Ivanova; E. A. Korolenko; E. V. Korolik; R. G. Zhbankov

1989-01-01

373

Electromagnetic Spectrum Management.  

National Technical Information Service (NTIS)

This report presents the results of an Air Force Occupational Survey of the Electromagnetic Spectrum Management career ladder, Air Force Specialty Code (AFSC) 3C1X2. Authority for conducting occupational surveys is contained in AFI 36-2623. Copies of this...

1997-01-01

374

Charging for Spectrum Use.  

ERIC Educational Resources Information Center

|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…

Geller, Henry; Lampert, Donna

375

Electromagnetic Spectrum Control Programs  

Microsoft Academic Search

The radio frequency spectrum is becoming increasingly saturated and polluted due to intensified use and unnecessary radiations and is being taxed severely to meet man's communications-electronics needs. Additional corrective measures are necessary-improved standards, increased concern for conservation of the resource, greater emphasis on intersystems compatibility, increased research, better educational and training programs, and the inclusion of economic and social values

Wilfred Dean

1971-01-01

376

Image Spectrum Analyzer.  

National Technical Information Service (NTIS)

A scanning device was developed for the purpose of recording a frequency power spectrum in a sample area of a photographic film in the form of a direct read-out. A rotary scanner, using an optical spot sufficiently small to obtain good modulation from a 2...

P. Rosten

1967-01-01

377

Spectrum of Nickel Hydride  

Microsoft Academic Search

RECENTLY we have observed the spectrum obtained by introducing nickel carbonyl vapour into the flame of a Meker burner. Just above the blue-green cones, in the hottest part of the flame, we find a very wide-spaced band structure which can only be attributed to a hydride.

A. G. Gaydon; R. W. B. Pearse

1934-01-01

378

Variance Spectrum Analysis.  

National Technical Information Service (NTIS)

Variance Spectrum Analysis stands as one of the 'tools of the trade' used by the geophysicist in his search for certain species of order which he suspects might be buried somewhere in the noisy recesses of his data sample. For certain jobs, it is a beauti...

A. Eddy C. E. Duchon J. A. Almazan

1968-01-01

379

A study analysis of cooperative spectrum sensing in cognitive radio networks  

NASA Astrophysics Data System (ADS)

Cognitive radios (CR) are designed in order to provide highly reliable communication for all users of the network, wherever and whenever needed and to facilitate effective utilization of the radio spectrum. In this paper, we analyzed local spectrum sensing for various fading channel scenario and also analyzed conventional cooperative spectrum sensing. We simulated various performance analysis for Additive White Gaussian Noise (AWGN), Rayleigh fading and cooperative spectrum sensing.

Kalimuthu, K.; Kumar, R.

2013-01-01

380

The spectrum of ?-ray burst: a clue  

NASA Astrophysics Data System (ADS)

In this work, we numerically calculate the thermal radiation efficiency of the baryonic outflow. The possible outflow acceleration in the transparent stage, which lowers thermal radiation efficiency, has been taken into account. In the standard internal shock model for the prompt emission, the fast shells should move with a typical Lorentz factor ~5 ?i otherwise the ?-ray burst (GRB) efficiency will be in disagreement with the observations, where ?i is the bulk Lorentz factor of the shocked/emitting region. The photosphere radius of these fast shells is small and the thermal radiation is too strong to be effectively outshone by the internal shock emission. This is particularly the case for some extremely bright events having ?i ~ 103, like GRBs 080319B and 080916C. The absence of a distinct thermal component in the spectrum of most GRBs challenges the standard internal shock model and may suggest a non-baryonic (magnetic) outflow component. Though the magnetic outflow model seems favoured by more and more data, it can hardly reproduce the typical GRB spectrum. In the photosphere-gradual magnetic dissipation scenario, the spectrum cuts off at ~1 GeV, too low to account for the observations of GRBs 080916C. In the sudden magnetic energy dissipation model, the low-energy spectrum is expected to be F? ~ ?-1/2, too soft to be consistent with the data F? ~ ?0. We speculate that the low-energy spectrum puzzle could be unveiled by the mechanism that particles, in the magnetic dissipation process, are repeatedly accelerated.

Fan, Yi-Zhong

2010-03-01

381

High-efficiency photonic crystal narrowband thermal emitters  

NASA Astrophysics Data System (ADS)

Photonic crystals (PhC) are artificial structures fabricated with a periodicity in the dielectric function. This periodic electromagnetic potential results in creation of energy bandgaps where photon propagation is prohibited. PhC structures have promising use in thermal applications if optimized to operate at specific thermal emission spectrum. Here, novel utilization of optimized PhC's in thermal applications is presented. We demonstrate through numerical simulation the modification of the thermal emission spectrum by a metallic photonic crystal (PhC) to create high-efficiency multispectral thermal emitters. These emitters funnel radiation from a broad emission spectrum associated with a Plancklike distribution into a prescribed narrow emission band. A detailed quantitative evaluation of the spectral and power efficiencies of a PhC thermal emitter and its portability across infrared (IR) spectral bands are provided. We show an optimized tungsten PhC with a predominant narrow-band emission profile with an emitter efficiency that is more than double that of an ideal blackbody and ~65-75% more power-efficiency across the IR spectrum. We also report on using optimal three-dimensional Lincoln log photonic crystal (LL-PhC) emitters for thermophotovoltaic (TPV) generation as opposed to using a passive filtering approach to truncate the broadband thermal source emission to match the bandgap of a photovoltaic (PV) cell. The emitter performance is optimized for the 1-2?m PV band using different PhC materials, specifically copper, silver and gold. The use of the proposed PhC in TPV devices can produce significant energy savings not reported before. The optimal design of the PhC geometry is obtained by implementing a variety of optimization methods integrated with artificial intelligence (AI) algorithms.

Farfan, G. B.; Su, M. F.; Reda Taha, M. M.; El-Kady, I.

2010-02-01

382

The social anxiety spectrum.  

PubMed

Social anxiety disorder is well suited to the spectrum concept because it has trait-like qualities of early onset, chronicity, and no empirically derived threshold that demarcates normal from clinically significant trait social anxiety. Social anxiety disorder has been shown to respond to relatively specific pharmacologic and cognitive-behavioral therapies, which makes identification of other conditions that may lie on the social anxiety disorder spectrum important because of possible treatment implications. Biologic markers associated with social anxiety disorder also may be shared by similar but nonidentical traits, such as behavioral inhibition and detachment. Clarification of the trait spectrums associated with specific biologic systems offers an opportunity for improving the understanding of the origin of these conditions. Strong evidence exists that at least some forms of shyness, avoidant personality disorder, and selective mutism lie on a social anxiety disorder spectrum. For several other disorders that share a prominent focus on social comparison, significant subgroups of patients seem to have features of social anxiety disorder. These disorders include major depression (especially the atypical subtype), body dysmorphic disorder, and eating disorders. Several other disorders marked by social dysfunction or inhibition, including substance use disorders (especially alcoholism), paranoid disorder, bipolar disorder, autism, and Asperger's disorder, also may show some overlap with social anxiety disorder features (e.g., social anxiety as a cause or complication of substance abuse, social avoidance in paranoid disorder, social disinhibiton in bipolar disorder, and social communication deficits in autism and Asperger's disorder). Social anxiety disorder also is associated with other anxiety disorders in general and other phobias in particular. In respect to traits, a growing body of evidence links behavioral inhibition to the unfamiliar to a social anxiety disorder spectrum with some specificity. Biologic measures of dopamine system hypoactivity have been linked to social anxiety disorder, trait detachment, and general deficits in reward and incentive function. It remains to be clarified, however, whether this brain system function is best characterized by a social anxiety disorder spectrum or some variant that incorporates social reward deficits or social avoidance behavior. Social anxiety disorder, shyness, and behavioral inhibition all seem to have a genetic component, but more research is needed to attempt to identify a more specifically heritable temperament associated with these conditions. Finally, the emergent concept of a social anxiety spectrum needs maturation. Although the notion of a single social anxiety disorder spectrum currently has some clinical use, the authors believe that exclusive focus on the notion of a single continuum with two extremes--from social disinhibition in mania to the most severe form of social anxiety, avoidant personality disorder--is premature and limiting in respect to etiologic research. An alternative approach is to conceptualize multiple, probably overlapping spectra in this area of social psychopathology. Individual dimensions might be based on various core phenomenologic, cognitive, or biologic characteristics. A bottom-up biologic approach holds promise for identifying spectra with a common etiology that might respond to specific treatments. Taking a pluralistic view of the concept of spectrum at this stage may help accelerate our understanding of social anxiety and related disorders. PMID:12462859

Schneier, Franklin R; Blanco, Carlos; Antia, Smita X; Liebowitz, Michael R

2002-12-01

383

Proton spectrum at the Jupiter laser facility of LLNL  

NASA Astrophysics Data System (ADS)

This paper looks at tungsten samples irradiated by beams of protons, gammas, electrons and positrons at the Jupiter Laser Facility (JLF) of Lawrence Livermore National Laboratory (LLNL). The resulting unstable nuclei created are identified using their gamma spectra. From the data and known production thresholds, a proton spectrum is extracted. This spectrum can be used to calculate background events for future research utilizing the positron beam.

Scarlett, Carol; Chen, Hui; Peterson, Jerry

2013-11-01

384

ENERGETIC EFFICIENT LIGHTING PROJECT - CASE STUDY  

Microsoft Academic Search

Aspects as contents of colors reproduction, color temperature spectrum, lamp efficiency, high power factor, and high efficiency of the reactor and luminous efficiency of the lamps have great importance for the making of an energetic efficient project. This paper investigates options that present smallest \\

Amâncio Rodrigues da Silva; Saulo Gomes Moreira; Wellington Rocha Araújo; Diego Bueno Angelo

385

Multitaper Spectrum Estimates  

NASA Astrophysics Data System (ADS)

Multitapering is a statistical technique developed to improve on the notorious periodogram estimate of the power spectrum (Thomson, 1982; Percival, Walden 1993). We show how to obtain orthogonal tapers for time series observed with gaps, and how to use statistical resampling techniques (Efron, Tibshirani 1993) to calculate realistic uncertainty estimates for multitaper estimates. We introduce multisegment multitapering. Multitapering can also be extended to the 2D case. We indicate how to construct tapers that minimize the spatial leakage in estimates of the spherical harmonic decomposition of the velocity images. Spatial multitapering followed by the temporal tapering of the estimated spherical harmonic time series is expected to result in improved spectrum and subsequent solar oscillation mode parameter estimates.

Fodor, I. K.; Stark, P. B.

386

Selling Spectrum Rights  

Microsoft Academic Search

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

John McMillan

1994-01-01

387

Autism Spectrum Disorders  

Microsoft Academic Search

Autism is a developmental disorder, characterized by repetitive behaviors and by deficits in social skills and communicative\\u000a abilities. Autism spectrum disorders affect 60 out of 10,000 individuals, resulting in significant costs to families and society.\\u000a Neuropathological and imaging studies point to abnormalities in the limbic system and the cerebellum, and accelerated brain\\u000a grown in the first 2 years of life.

Evdokia Anagnostou; Eric Hollander

388

Time delay spectrum conditioner  

DOEpatents

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.

Greiner, Norman R. (Los Alamos, NM)

1980-01-01

389

UV spectrum of Enceladus  

NASA Astrophysics Data System (ADS)

We present a far ultraviolet (FUV) spectrum of Saturn's moon Enceladus from the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST). We have put upper limits on emission from C, N, and O lines in Enceladus' atmosphere and column densities for the C lines assuming solar resonance scattering. We find these upper limits to be relatively low—on the order of tens to thousands of Rayleighs and with C column densities on the order of 108-1015 cm-2, depending on the assumed source size. We also present a segment of a reflectance spectrum in the FUV from ˜1900-2130 Å. This region was sensitive to the different ice mixtures in the model spectra reported by Hendrix et al. (Hendrix, A.R., Hansen, C.J., Holsclaw, G.M. [2010]. Icarus, 206, 608). We find the spectrum brightens quickly longward of ˜1900 Å, constraining the absorption band observed by Hendrix et al. from ˜170 to 190 nm. We find our data is consistent with the suggestion of Hendrix et al. of the presence of ammonia ice (or ammonia hydrate) to darken that region, and also possibly tholins to darken the mid-UV, as reported by Verbiscer et al. (Verbiscer, A.J., French, R.G., McGhee, C.A. [2005]. Icarus, 173, 66).

Zastrow, Mark; Clarke, John T.; Hendrix, Amanda R.; Noll, Keith S.

2012-07-01

390

CD spectrum of bacteriorhodopsin  

PubMed Central

We summarize the predictions of the exciton model that was originally proposed to explain the observed biphasic band shape of its CD spectrum in the visible region of bacteriorhodopsin (bR). It is shown that to reconcile these predictions with the observed results on the linear dichroism, the retinal isomerization time and, the retinal-retinal distance, the biphasic nature of the observed CD spectrum of bR becomes itself an evidence against the exciton model because of the uncertainty principle. Reduced bR (RbR), which retains its hexagonal structure, shows a monophasic CD spectrum with relatively small rotational strength as compared to bR. This is shown to disagree with predictions made by the exciton model. The results could best be explained in terms of retinal-protein heterogeneity leading to two or more types of bR in which their retinals suffer opposite sense of intramolecular rotational distortion along their retinal long axis. Such a retinal-protein heterogeneity disappears in reduced bR which is known to have a planar (nondistorted) retinal conjugated system, resulting in a monophasic CD with reduced rotational strength, as observed.

Wu, Shuguang; El-Sayed, Mostafa A.

1991-01-01

391

Dynamic spectrum access in open spectrum wireless networks  

Microsoft Academic Search

One of the reasons for the limitation of bandwidth in current generation wireless networks is the spectrum policy of the Federal Communications Commission (FCC). But, with the spec- trum policy reform, open spectrum wireless networks, and spec- trum agile radios are set to drive next general wireless networks. In this paper, we investigate continuous-time Markov models for dy- namic spectrum

Yiping Xing; Rajarathnam Chandramouli; Stefan Mangold

2006-01-01

392

Definitions of Relevant Efficiency and Stress Factors.  

National Technical Information Service (NTIS)

A general efficiency function and related stress factors are defined from energy flow considerations. The efficiency function, or index, is related to maximum energy utilization, and stress is defined as total derivatives of the efficiency function. The e...

U. Wahlgren

1981-01-01

393

Definitions of Relevent Efficiency and Stress Factors.  

National Technical Information Service (NTIS)

A general efficiency function and related stress factors are defined from energy flow considerations. The efficiency function, or index, is related to maximum energy utilization, and stress is defined as total derivatives of the efficiency function. The e...

U. Wahlgren

1981-01-01

394

Spectrum tailoring of the neutron energy spectrum in the context of delayed neutron detection  

SciTech Connect

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.

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

395

Spectrum Services 2007  

NASA Astrophysics Data System (ADS)

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.

Dobos, L.; Budavári, T.; Csabai, I.; Szalay, A. S.

2008-10-01

396

Time Utilities  

NASA Astrophysics Data System (ADS)

Time Utilities are software tools that, in principal, allow one to calculate BJD to a precision of 1 ?s for any target from anywhere on Earth or from any spacecraft. As the quality and quantity of astrophysical data continue to improve, the precision with which certain astrophysical events can be timed becomes limited not by the data themselves, but by the manner, standard, and uniformity with which time itself is referenced. While some areas of astronomy (most notably pulsar studies) have required absolute time stamps with precisions of considerably better than 1 minute for many decades, recently new areas have crossed into this regime. In particular, in the exoplanet community, we have found that the (typically unspecified) time standards adopted by various groups can differ by as much as a minute. Left uncorrected, this ambiguity may be mistaken for transit timing variations and bias eccentricity measurements. We recommend using BJD_TDB, the Barycentric Julian Date in the Barycentric Dynamical Time standard for any astrophysical event. The BJD_TDB is the most practical absolute time stamp for extraterrestrial phenomena, and is ultimately limited by the properties of the target system. We compile a general summary of factors that must be considered in order to achieve timing precisions ranging from 15 minutes to 1 ?s, and provide software for download and online webapps for use.

Eastman, Jason

2012-06-01

397

Hybrid spread spectrum radio system  

DOEpatents

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.

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

2010-02-09

398

ACBAR CMB Power Spectrum  

NASA Astrophysics Data System (ADS)

We report the first measurements of anisotropy in the cosmic microwave background (CMB) radiation with the Arcminute Cosmology Bolometer Array Receiver (ACBAR). The instrument was installed on the 2.1 m Viper telescope at the South Pole in December 2000; the data presented here are the product of observations up to and including July 2002. The large 3 degree extent of the maps, and small beamsize of the experiment allow the measurement of the CMB anisotropy power spectrum over the range l = 150-3000 with resolution of ? l=150. We discuss the observation strategy, analysis method, and the cosmological implication of the results.

Kuo, C.-L.; Ade, P.; Bock, J. J.; Daub, M. D.; Goldstein, J.; Holzapfel, W. L.; Lange, A. E.; Newcomb, M.; Peterson, J. B.; Ruhl, J.; Runyan, M. C.; Torbet, E.

2002-12-01

399

The Earthshine Spectrum  

NASA Astrophysics Data System (ADS)

Since 1998 the Earthshine Project has been a collaborative effort between Big Bear Solar Observatory/New Jersey Institute of Technology and the California Institute of Technology. Cyclic spectroscopic observations of the dark and bright sides of the moon (or earthshine and moonshine respectively) have been carried out in the visible range at Palomar Observatory. The ratio of the earthshine to moonshine spectra characterizes the globally averaged Earth's spectrum. These observations allow us to study global averaged column densities for several trace and non-trace atmospheric components. Revelant information concerning to the search of extra-solar, terrestrial-like planets can be also obtained from these observations.

Montanes Rodriguez, P.; Palle, E.; Goode, P. R.; Koonin, S. E.; Qiu, J.

2003-04-01

400

The earthshine spectrum  

NASA Astrophysics Data System (ADS)

Since 1998 the Earthshine Project has been a collaborative effort between Big Bear Solar Observatory/New Jersey Institute of Technology and California Institute of Technology. Cyclic spectroscopic observations of the dark and bright sides of the moon (or earthshine and moonshine, respectively) have been carried out in the visible region at Palomar Observatory. From these data, the ratio of the earthshine to moonshine characterizes the globally averaged Earth's spectrum. Information concerning the search for extra-solar, terrestrial planets can be also obtained from these observations.

Montañés Rodriguez, P.; Pallé, E.; Goode, P. R.; Hickey, J.; Qiu, J.; Yurchyshyn, V.; Chu, M. C.; Kolbe, E.; Brown, C. T.; Koonin, S. E.

2004-01-01

401

Efficient Windows Collaborative  

SciTech Connect

The project goals covered both the residential and commercial windows markets and involved a range of audiences such as window manufacturers, builders, homeowners, design professionals, utilities, and public agencies. Essential goals included: (1) Creation of 'Master Toolkits' of information that integrate diverse tools, rating systems, and incentive programs, customized for key audiences such as window manufacturers, design professionals, and utility programs. (2) Delivery of education and outreach programs to multiple audiences through conference presentations, publication of articles for builders and other industry professionals, and targeted dissemination of efficient window curricula to professionals and students. (3) Design and implementation of mechanisms to encourage and track sales of more efficient products through the existing Window Products Database as an incentive for manufacturers to improve products and participate in programs such as NFRC and ENERGY STAR. (4) Development of utility incentive programs to promote more efficient residential and commercial windows. Partnership with regional and local entities on the development of programs and customized information to move the market toward the highest performing products. An overarching project goal was to ensure that different audiences adopt and use the developed information, design and promotion tools and thus increase the market penetration of energy efficient fenestration products. In particular, a crucial success criterion was to move gas and electric utilities to increase the promotion of energy efficient windows through demand side management programs as an important step toward increasing the market share of energy efficient windows.

Nils Petermann

2010-02-28

402

Proceedings of an EPRI Workshop on Technologies for Conservation and Efficient Utilization of Electric Energy Held at San Diego, California on July 26-30, 1976. Volume I: Overview.  

National Technical Information Service (NTIS)

Topic areas briefly discussed are: Objectives in an energy end-use program; Programs relating to energy conservation; Energy storage and heat pumps--lessons learned; Solar heating and cooling of buildings - a utility perspective; Economic analysis of ener...

F. Kalhammer

1976-01-01

403

Design and Analysis of Hybrid Solar Lighting and Full-Spectrum Solar Energy Systems  

SciTech Connect

This paper describes a systems-level design and analysis of a new approach for improving the energy efficiency and affordability of solar energy in buildings, namely, hybrid solar lighting and full-spectrum solar energy systems. By using different portions of the solar spectrum simultaneously for multiple end-use applications in buildings, the proposed system offers unique advantages over other alternatives for using sunlight to displace electricity (conventional topside daylighting and solar technologies). Our preliminary work indicates that hybrid solar lighting, a method of collecting and distributing direct sunlight for lighting purposes, will alleviate many of the problems with passive daylighting systems of today, such as spatial and temporal variability, glare, excess illumination, cost, and energy efficiency. Similarly, our work suggests that the most appropriate use of the visible portion of direct, nondiffuse sunlight from an energy-savings perspective is to displace electric light rather than generate electricity. Early estimates detailed in this paper suggest an anticipated system cost of well under $2.0/Wp and 5-11 {cents}/kWh for displaced and generated electricity in single-story commercial building applications. Based on a number of factors discussed in the paper, including sunlight availability, building use scenarios, time-of-day electric utility rates, cost, and efficacy of the displaced electric lights, the simple payback of this approach in many applications could eventually be well under 5 years.

Muhs, J.D.

2001-06-19

404

Electric utilities in 2007  

SciTech Connect

A century ago--in the year J.J. Thomson discovered the electron--electricity, gas and traction companies battled for markets, and corrupt city councils demanded their fair share of the take. One tycoon became so disgusted with the confusion and dishonesty that he decided to bribe the legislature to set up an honest, state-run regulatory agency that would bring order to chaos. But he was found out. The scandal set back the cause of regulation until 1907, the year in which the electric washing machine and the vacuum cleaner were invented. By then, electricity sales had septupled from 1897 levels, and three states had established utility regulation. In the coming decade, 1997 to 2007, the utility business could undergo similar dramatic change, but it will move toward less regulation and more competition during a period of slow growth. Management will have to work harder to achieve success, however, because much of the profits will have to come not from a growing market but from the pockets of competitors. By 2007, electricity will constitute a component of a larger energy and utility services industry that sells electricity, natural gas and possibly water, propane and telecommunications. Customized service will meet the needs of consumers of all sizes. The dominant firm in the industry, the virtual utility, may look more like a financial organization or a mass marketer than the traditional converter of raw material to energy. Emphasis on market-based pricing should lead to more efficient use of resources. If the process works right, the consumer wins.

Hyman, L.S. [Smith Barney Inc., New York, NY (United States)

1998-10-01

405

Microwave Spectrum of Hexafluoroisopropanol  

NASA Astrophysics Data System (ADS)

Hexafluoroisopropanol (HFIP) is an important organic solvent and probably the only solvent which can dissolve polythene. IR studies, on this molecule confirm the existence of antiperiplanar (ap) and synclinical (sc) conformers. We have observed pure rotational spectrum of this molecule and the fitted rotational constants (A= 2105.1208(11) MHz, B= 1053.9942(3) MHz, C= 932.3398(3) MHz) confirm the presence of ap conformer. There are many other observed lines which most probably corresponds to sc structure and due to the large amplitude motion of H-atom, some of these transitions show tunneling splitting. Work is in progress for the deuterated (OD) and C-13 isotopologues of the monomer. HFIP is expected to exhibit interesting hydrogen bonding properties and we are planning to investigate them by studying its complex with water. The results will be presented in this talk. H. Schaal, T. Höber, and M. A. Suhm, J. Phys. Chem. A 104, 265 (2000).

Shahi, Abhishek; Mani, Devendra; Arunan, E.

2012-06-01

406

Autism spectrum disorders  

PubMed Central

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.

Faras, Hadeel; Al Ateeqi, Nahed; Tidmarsh, Lee

2010-01-01

407

Broad spectrum bioactive sunscreens.  

PubMed

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

Velasco, Maria Valéria Robles; Sarruf, Fernanda Daud; Salgado-Santos, Idalina Maria Nunes; Haroutiounian-Filho, Carlos Alberto; Kaneko, Telma Mary; Baby, André Rolim

2008-07-09

408

Supporting Dynamic Spectrum Access in Heterogeneous LTE+ Networks  

SciTech Connect

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.

Luiz A. DaSilva; Ryan E. Irwin; Mike Benonis

2012-08-01

409

Narrow-band recursive filters with error spectrum shaping  

Microsoft Academic Search

Earrrs due to Finite wordlength can be quite large in narrowband recursive digital filters. It has been shown that these errors may be considerably reduced by using a technique known as error spectrum shaping (ESS), which utilizes quantizer feedback. In this letter we first derive closed-formn bounds on the amplitude of zero-input limit cycles in ESS filters. An expression is

DAVID C. MUNSON; B. Liu

1981-01-01

410

Spectrum Enforcement and Liability Assignment in Cognitive Radio Systems  

Microsoft Academic Search

The advent of frequency-agile radios holds the potential for improving the utilization of spectrum by allowing wireless systems to dynamically adapt their spectral footprint based on the local conditions. Whether this is done using market mechanisms or opportunistic approaches, the gains result from shifting some responsibility for avoiding harmful interference from the static \\

George Atia; Anant Sahai; Venkatesh Saligrama

2008-01-01

411

Error Probability of Asynchronous Spread Spectrum Multiple Access Communication Systems  

Microsoft Academic Search

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

Kung Yao

1977-01-01

412

Early Onset Bipolar Spectrum Disorder: Psychopharmacological, Psychological, and Educational Management  

ERIC Educational Resources Information Center

|Although published research continues to advocate medication as the first line of treatment for early onset bipolar spectrum disorder (EOBSD; N. Lofthouse & M.A. Fristad, 2004), preliminary research demonstrating the utility of cognitive, cognitive-behavioral, and psychoeducational therapies is promising. It appears as if future treatment of…

McIntosh, David E.; Trotter, Jeffrey S.

2006-01-01

413

Early Onset Bipolar Spectrum Disorder: Psychopharmacological, Psychological, and Educational Management  

ERIC Educational Resources Information Center

Although published research continues to advocate medication as the first line of treatment for early onset bipolar spectrum disorder (EOBSD; N. Lofthouse & M.A. Fristad, 2004), preliminary research demonstrating the utility of cognitive, cognitive-behavioral, and psychoeducational therapies is promising. It appears as if future treatment of EOBSD…

McIntosh, David E.; Trotter, Jeffrey S.

2006-01-01

414

Cooperative spectrum sensing and signal detection in cognitive radio  

Microsoft Academic Search

Cognitive radio (CR) is expected to be the key enabling technology for increased spectrum utilization. As primary user activity is not spatially localized, a collaborative measure amongst multiple cognitive radio nodes has been suggested as a more accurate model of activity. This scheme was proposed to combat noise fading and shadowing as well as improves the probability of detection by

Nasrullah Armi; N. M. Saad; M. Zuki Y; M. Arshad

2010-01-01

415

Improved motors for utility applications  

NASA Astrophysics Data System (ADS)

The reliability and performance of powerhouse motors was evaluated and design and operational characteristics which, through advanced development, offer the potential of increased reliability, performance, and efficiency were identified. A data base of utility motor applications, operating factors, failures, causes of failures, and impacts of failures on the operation of the generating station was developed. A survey of 132 generating units was conducted and data on 4800 low and medium voltage motors with ratings greater than 100 hp was obtained. Results are presented relating motor failures to units, utilities, manufacturers, and applications. A separate survey was undertaken with the goal of documenting utility industry experience in using vacuum devices to switch motors in generating station auxiliaries systems. Eleven utilities were identified as having installations involving vacuum switching devices at 12 generating stations representing 122 motors.

Cornell, E. P.; Owen, E. L.; Appiarius, J. C.; McCoy, R. M.; Albrecht, P. F.; Houghtaling, D. W.

1982-10-01

416

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

SciTech Connect

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.

Tolbert, L.M.

2005-12-21

417

Method to reconstruct exoplanetary spectrum.  

PubMed

We present a method for spectroscopic observations of exoplanets. Coronagraphic image of a star-planet system and its objective spectra are observed simultaneously. Stellar image and objective spectrum without coronagraphic suppression are also obtained as reference. By convolution of the coronagraphic image with the reference stellar spectrum, pseudo-objective spectra are synthesized. The difference between the observed and the synthesized pseudospectra reveals the distinctive features of planetary spectrum. We carry out laboratory demonstration of the proposed technique and show that the planetary spectrum is reconstructed. PMID:19684806

Zubko, N; Baba, N; Shibuya, H; Murakami, N

2009-08-15

418

Asynchronous spread spectrum communication paradigm for use in low-power applications: description and simulation results  

NASA Astrophysics Data System (ADS)

Contemporary wireless communication strategies focus on efficient use of bandwidth in order to allow more users to exploit the RF spectrum through techniques like Frequency-hopping spread spectrum (SS) and Direct-sequence SS. In many real-world applications, these methods are implemented for synchronous communication systems. To achieve synchronous communication, two-way handshaking that requires overhead circuitry is performed between the sender and receiver. In order to use spread spectrum methods for certain unconstrained and low-power applications, such as implantable and remote monitoring devices, it is necessary to refine these methods to support asynchronous communication. We have designed and modeled a SS system, which could be integrated with a custom integrated circuit that would provide elementary multi-user communication. The SS logic generates a gold-code based on address and data bits that is then modulated with a carrier to transmit the information. Because the system is asynchronous, we treat each transmitted code as an independent piece of information. The receiver decodes the information using a full correlation with the ideal known gold-codes. For efficiency purposes, the filter is applied in the frequency domain. A threshold is applied to the output of the filter to determine if a particular code is transmitted as well as the point in time/space from which the signal was sent. The method was simulated and evaluated under several scenarios including different carrier frequencies, multiple targets, and various positions relative to the receiver from the simulated receiver. The results demonstrate the utility of asynchronous SS under many different conditions.

Welch, E. B.; Holmes, David R., III; Coker, Jonathan D.; Schaefer, Timothy M.; Gilbert, Barry K.; Daniel, Erik S.

2005-06-01

419

Free-form Fresnel RXI-RR Köhler design for high-concentration photovoltaics with spectrum-splitting  

NASA Astrophysics Data System (ADS)

Development of a novel HCPV nonimaging concentrator with high concentration (>500x) and built-in spectrum splitting concept is presented. It uses the combination of a commercial concentration GaInP/GaInAs/Ge 3J cell and a concentration Back-Point-Contact (BPC) silicon cell for efficient spectral utilization, and external confinement techniques for recovering the 3J cell's reflection. The primary optical element (POE) is a flat Fresnel lens and the secondary optical element (SOE) is a free-form RXI-type concentrator with a band-pass filter embedded in it - Both the POE and SOE performing Köhler integration to produce light homogenization on the receiver. The band-pass filter transmits the IR photons in the 900-1200 nm band to the silicon cell. A design target of an "equivalent" cell efficiency ~46% is predicted using commercial 39% 3J and 26% Si cells. A projected CPV module efficiency of greater than 38% is achievable at a concentration level larger than 500X with a wide acceptance angle of +/-1°. A first proof-of concept receiver prototype has been manufactured using a simpler optical architecture (with a lower concentration, ~100x and lower simulated added efficiency), and experimental measurements have shown up to 39.8% 4J receiver efficiency using a 3J cell with a peak efficiency of 36.9%.

Buljan, M.; Benítez, P.; Mohedano, R.; Miñano, J. C.; Sun, Y.; Falicoff, W.; Vilaplana, J.; Chaves, J.; Biot, G.; López, J.

2011-09-01

420

Synthesis of power efficient multitone signals with flat amplitude spectrum  

Microsoft Academic Search

It is shown that, generally, any binary or polyphase sequence belonging to a pair of complementary sequences can be used to construct the initial phases of tones forming a multitone signal with the crest factor less than or equal to 6 dB. The previously proposed Shapiro-Rudin sequences are representatives of a much larger family of binary Golay complementary sequences. Numerical

B. M. Popovic

1991-01-01

421

Purging the BackRoom Dealing: Secure Spectrum Auction Leveraging Paillier Cryptosystem  

Microsoft Academic Search

Microeconomics-inspired spectrum auctions can dramatically improve the spectrum utilization for wireless net- works to satisfy the ever increasing service demands. However, the back-room dealing (i.e., the frauds of the insincere auc- tioneer and the bid-rigging between the greedy bidders and the auctioneer) poses significant security challenges, and fails all existing secure auction designs to allocate spectrum bands when considering the

Miao Pan; Jinyuan Sun; Yuguang Fang

2011-01-01

422

Rotational Spectrum of Sarin  

NASA Astrophysics Data System (ADS)

As part of an effort to examine the possibility of using molecular-beam Fourier-transform microwave spectroscopy to unambiguously detect and monitor chemical warfare agents, we report the first observation and assignment of the rotational spectrum of the nerve agent Sarin (GB) (Methylphosphonofluoridic acid 1-methyl-ethyl ester, CAS #107-44-8) at frequencies between 10 and 22 GHz. Only one of the two low-energy conformers of this organophosphorus compound (C4H10FO2P) was observed in the rotationally cold (Trot<2 K) molecular beam. The experimental asymmetric-rotor ground-state rotational constants of this conformer are A=2874.0710(9) MHz, B=1168.5776(4) MHz, C=1056.3363(4) MHz (Type A standard uncertainties are given, i.e., 1?), as obtained from a least-squares analysis of 74 a-, b-, and c-type rotational transitions. Several of the transitions are split into doublets due to the internal rotation of the methyl group attached to the phosphorus. The three-fold-symmetry barrier to internal rotation estimated from these splittings is 677.0(4) cm-1. Ab initio electronic structure calculations using Hartree-Fock, density functional, and Moller-Plesset perturbation theories have also been made. The structure of the lowest-energy conformer determined from a structural optimization at the MP2/6-311G** level of theory is consistent with our experimental findings.

Walker, A. R. Hight; Suenram, R. D.; Samuels, Alan; Jensen, James; Ellzy, Michael W.; Lochner, J. Michael; Zeroka, Daniel

2001-05-01

423

Transmitter spectrum analyzer  

NASA Astrophysics Data System (ADS)

A spectrum analyzer for 7 MHz single-sideband transmitters of two tone signals at 1 and 1.8 kHz, respectively, on a 14,200 kHz carrier, has been developed as a means for monitoring the amplifier linearity and the intermodulation level. The instrument includes an adjustable attenuating resistor, a resistive decoupler, a ring mixer (KD503 or equivalent high-frequency silicon diodes) separated from the heterodyne stage (quartz oscillator and KP302 or KP303 field-effect transistor) by an emitter follower (KT312 or KT606 transistor), two low-pass filters (LC filter and second-order active filter using an operational amplifier), a low-frequency a.c. millivoltmeter using an operational ammplifier, a transformer (PEV-2/0.3 wire on ferrite ring core), a 50-200 microammeter, and a light-emitting indicator diode. Adjustment of the analyzer for operation begins with checking the performance of transistors in the d.c. mode, followed by trimming a LED resistor for threshold-sensitivity current, applying an audio signal, and oscillographically recording the amplitude-frequency characteristic, then applying a high-frequency signal.

Stepanov, B.; Shulgin, G.

1984-03-01

424

The anxiety disorder spectrum  

PubMed Central

This review considers recent research assessing psychophysiological reactivity to fear imagery in anxiety disorder patients. As in animal subjects, fear cues prompt in humans a state of defensive motivation in which autonomic and somatic survival reflexes are markedly enhanced. Thus, a startle stimulus presented in a fear context yields a stronger (potentiated) reflex, providing a quantitative measure of fearful arousal. This fear potentiation is further exaggerated in specific or social phobia individuals when viewing pictures or imagining the phobic object. Paradoxically, fear imagery studies with more severe anxiety disorder patients—panic disorder with agoraphobia, generalized anxiety disorder, or anxious patients with comorbid depression—show a blunted, less robust fear potentiated response. Furthermore, this reflex blunting appears to systematically be more pronounced over the anxiety disorder spectrum, coincident with lengthier chronicity, worsening clinician-based judgments of severity and prognosis, and increased questionnaire-based indices of negative affectivity, suggesting that normal defensive reactivity may be compromised by an experience of long-term stress.

Lang, Peter J.; McTeague, Lisa M.

2008-01-01

425

PINS Spectrum Identification Guide  

SciTech Connect

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.

A.J. Caffrey

2012-03-01

426

Sequence and Spread Spectrum Time Domain Reflectometry for Transmission Line Analysis  

Microsoft Academic Search

This paper describes Sequence Time Domain Reflectometry (STDR) and Spread Spectrum Time Domain Reflec- tometry (SSTDR), which utilizes concepts from direct sequence spread spectrum communications, as a technique for detecting impedance mismatches in telephone lines (twisted pair). The aim of this paper is to present method- ologies for characterizing a subscriber loop, which is used for Digital Subscriber Line (DSL)

Jacklyn Reis; Agostinho L. S. Castro; Joao C. W. A Costa; Jaume R. I. Riu

427

Sequence and spread spectrum time domain reflectometry for transmission line analysis  

Microsoft Academic Search

This paper describes Sequence Time Domain Reflectometry (STDR) and Spread Spectrum Time Domain Reflectometry (SSTDR), which utilizes concepts from direct sequence spread spectrum communications, as a technique for detecting impedance mismatches in telephone lines (twisted pair). The aim of this paper is to present methodologies for characterizing a subscriber loop, which is used for Digital Subscriber Line (DSL) technology, based

Jacklyn Reis; Agostinho L. S. Castro; João C. W. A. Costa; Jaume R. I. Riu; Klas Ericson

2007-01-01

428

Discontiguous OFDM considerations for dynamic spectrum access in idle TV channels  

Microsoft Academic Search

Sharing spectrum with systems that employ frequency reuse over large geographical areas (e.g., TV stations) provides an opportunity to improve spectrum utilization. The Federal Communications Commission (FCC) is considering such sharing in the TV hands (2004). This technical and regulatory opportunity prompted the IEEE to create a new committee, 802.22, that will develop a wireless regional area network (WRAN) standard

Jeffrey D. Poston; William D. Horne

2005-01-01

429

Three ways to decouple electric-utility revenues from sales.  

National Technical Information Service (NTIS)

Utility energy efficiency programs hurt shareholders because these programs reduce electricity use, and this reduction lowers revenues by more than costs are cut. Utilities and their regulators have adopted various methods to deal with these net lost reve...

E. Hirst E. Blank D. Moskovitz

1994-01-01

430

The Utility Battery Storage Systems Program Overview  

SciTech Connect

Utility battery energy storage allows a utility or customer to store electrical energy for dispatch at a time when its use is more economical, strategic, or efficient. The UBS program sponsors systems analyses, technology development of subsystems and systems integration, laboratory and field evaluation, and industry outreach. Achievements and planned activities in each area are discussed.

Not Available

1994-11-01

431

Optimizing Benchmark-Based Utility Functions  

Microsoft Academic Search

We Consider Four Utility Functions, Each Of Which Incorporates A Benchmark To Better Capture The Motivations Of Today's Portfolio Managers. Assuming Instrument Returns Are Normally Distributed, We Establish Conditions Under Which Optimal Portfolios For These Utilities Are Mean-Variance Efficient And We Briefly Discuss Computing Solutions Of The Models Via Standard Nonlinear Programming Tools. When Returns Are Not Normally Distributed, We

David P. Morton; Elmira Popova; Ivilina Popova; Ming Zhong

2003-01-01

432

Raman Spectrum of Crystalline Benzil.  

National Technical Information Service (NTIS)

The Raman spectrum of the optically active organic crystal benzil, C6H5COCOC6H5, belonging to the point group D3, is studied with the 6328 A radiation from a He-Ne laser as the exciting radiation. From the correlation of the observed spectrum, consisting ...

S. A. Solin A. K. Ramdas

1968-01-01

433

Raman spectrum of amorphous diamond.  

National Technical Information Service (NTIS)

The Raman spectrum of an amorphous, fully sp(sup 3)-bonded carbon network is presented. The reduced Raman spectrum agrees closely with the calculated density of states of diamond. The results have been obtained from nanoclusters produced deep inside a sin...

S. Prawer K. W. Nugent D. Jamieson

1997-01-01

434

Spectrum analysis of lung sounds  

Microsoft Academic Search

The power spectra of vesicular breathing, rale and wheeze from 40 people (including normal people and people with lung diseases) were analysed by BSFA (zoom fast Fourier transform). The distribution of spectrum peak frequencies was estimated. It is noted that the vesicular breathing of normal people and abnormal breathing (rale and wheeze) are significantly different in their distribution of spectrum

Jingping Xu; Qimin Chen; Yili Zhang; Shuyan Liu

1989-01-01

435

The worldwide leaf economics spectrum  

Microsoft Academic Search

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

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

436

The HIV mental health spectrum  

Microsoft Academic Search

The growing mental health needs that are related to HIV are immense and diverse. The HIV mental health spectrum is a model that identifies and characterizes populations in need of HIV-related services which can be offered by Community Mental Health Centers. The spectrum describes the specialized service requirements for each of these populations, the challenges in providing these services, and

Michael D. Knox; Maryann Davis; Martha A. Friedrich

1994-01-01

437

Spectrum of Doubly Ionised Iodine  

Microsoft Academic Search

WORK on the identification of the lines belonging to this spectrum was begun more than four years ago and a preliminary announcement on a clue obtained which was expected to lead to an analysis of the spectrum was made at the time in these columns1. That clue, however, did not lead to the expected result, and had to be abandoned.

J. B. Seth

1935-01-01

438

The Electromagnetic Spectrum: Infrared Waves  

NSDL National Science Digital Library

This webpage, part of a NASA site on the electromagnetic spectrum, presents information on infrared light. An explanation of how objects emit infrared is provided, along with a diagram of the electromagnetic spectrum. The site contains a number of photos made with infrared light.

2007-06-24

439

Frequency Allocation; The Radio Spectrum.  

ERIC Educational Resources Information Center

|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…

Federal Communications Commission, Washington, DC.

440

Efficient autonomous heliostat system  

Microsoft Academic Search

In this work, an efficient autonomous solar energy system has been implemented for domestic use. It concentrates the solar heat to turn water into steam which in turn is channelled to drive an electricity turbine-generator. The prototype utilizes two heliostat reflector units, each of which has been designed to accurately and independently track the sun throughout the day and reflect

Nazar T. Ali; Kahtan A. Mezher; Ahmed Al Qayed; Neil McEwan; Abdul Muhsin M. Altimimi

2012-01-01

441

Utilization of water/alcohol-soluble polyelectrolyte as an electron injection layer for fabrication of high-efficiency multilayer saturated red-phosphorescence polymer light-emitting diodes by solution processing  

NASA Astrophysics Data System (ADS)

Highly efficient multilayer red polymer light-emitting diodes were fabricated by solution process-ing from iridium complex, bis(1-(3-(9,9-dimethyl-fluorene-2-yl)phenyl)isoquinoline-C2,N') iridium(III)acetylacetonate, doped into polyfluorene as a host and with a water/alcohol-soluble polymer, poly[(9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)propyl)-2,7-fluorene)-2,7-(9,9-dioctylfluorene)-4,7-(2,1,3-benzoselenadiazole)]dibromide (PFN) as electron injection layer. The device with the structure ITO/PEDOT-PSS(50 nm)/PVK(40 nm)/PFO:PBD:Ir(DMFPQ)2acac(2%,75 nm)/PFN(20 nm)/Ba(4.5 nm)/Al(150 nm) showed an external quantum efficiency of 18.0% and luminance efficiency of 9.8 Cd/A at a current density of 1.1 mA/cm2, a peak emission at ?max=636 nm, and Commission International de I'Eclairage coordinates of (0.665, 0.319). The efficiency remained as high as QE=11.1%, and LE=6.0 cd/A, at a current density of 100 mA/cm2, and a luminance of 6140 cd/m2.

Wang, Lei; Liang, Bo; Huang, Fei; Peng, Junbiao; Cao, Yong

2006-10-01

442

Omaha utility tests trenchless units  

SciTech Connect

Like all gas utilities, Metropolitan Utility District of Omaha, Neb., is always looking for better, more efficient ways of installing underground facilities. The utility's growth plan was having an effect on the type of work performed by the construction division. Gas main installations in fully developed, all-electric subdivisions were becoming more common. This paper reports that this type of work involved extensive restoration when performed by conventional methods, due to the presence of established lawns, landscaping, driveways and other underground utilities, that added significantly to the overall cost of the project. Disruption of the lawns was an inconvenience and nuisance to the utility's customers, which the district wanted to minimize in the interest of good customer and public relations. As a result, the utility scheduled field demonstrations by various boring equipment makers. After several less-than-successful demonstrations by various manufacturers, the MUD contacted Midwest Pow-R Mole Co. Inc., for a test of the new Pow-R Mole directional boring system. The system was developed by Pow-R Devices Inc., Clarence Center, N.Y.

Not Available

1992-04-01

443

Navy and Marine Corps Spectrum Offices (NMCSO) Status: Spectrum Management Challenges for the 21st Century.  

National Technical Information Service (NTIS)

Overview: * Primary Mission Responsibilities * Organizational Chain of Command * NMCSO Regions * Afloat Spectrum Support * Shore Spectrum Support * Manning * Spectrum Management Immediate Challenges > Documentation >> NTP-6 Published rewrite. >> Fleet gui...

K. Van Blarcom

2010-01-01

444

77 FR 40647 - Toward Innovative Spectrum-Sharing Technologies: Wireless Spectrum Research and Development...  

Federal Register 2010, 2011, 2012, 2013

...Spectrum-Sharing Technologies: Wireless Spectrum Research...Networking and Information Technology Research and Development...on Unleashing the Wireless Broadband Revolution...spectrum-sharing technologies.'' The WSRD...

2012-07-10

445

Tribal Utility Feasibility Study  

SciTech Connect

The Schatz Energy Research Center (SERC) assisted the Yurok Tribe in investigating the feasibility of creating a permanent energy services program for the Tribe. The original purpose of the DOE grant that funded this project was to determine the feasibility of creating a full-blown Yurok Tribal electric utility to buy and sell electric power and own and maintain all electric power infrastructure on the Reservation. The original project consultant found this opportunity to be infeasible for the Tribe. When SERC took over as project consultant, we took a different approach. We explored opportunities for the Tribe to develop its own renewable energy resources for use on the Reservation and/or off-Reservation sales as a means of generating revenue for the Tribe. We also looked at ways the Tribe can provide energy services to its members and how to fund such efforts. We identified opportunities for the development of renewable energy resources and energy services on the Yurok Reservation that fall into five basic categories: • Demand-side management – This refers to efforts to reduce energy use through energy efficiency and conservation measures. • Off-grid, facility and household scale renewable energy systems – These systems can provide electricity to individual homes and Tribal facilities in areas of the Reservation that do not currently have access to the electric utility grid. • Village scale, micro-grid renewable energy systems - These are larger scale systems that can provide electricity to interconnected groups of homes and Tribal facilities in areas of the Reservation that do not have access to the conventional electric grid. This will require the development of miniature electric grids to serve these interconnected facilities. • Medium to large scale renewable energy development for sale to the grid – In areas where viable renewable energy resources exist and there is access to the conventional electric utility grid, these resources can be developed and sold to the wholesale electricity market. • Facility scale, net metered renewable energy systems – These are renewable energy systems that provide power to individual households or facilities that are connected to conventional electric utility grid.

Engel, R. A.; Zoellick, J. J.

2007-06-30

446

High Efficiency, Long Life Terrestrial Solar Panel.  

National Technical Information Service (NTIS)

The design of a high efficiency, long life terrestrial module was completed. It utilized 256 rectangular, high efficiency solar cells to achieve high packing density and electrical output. Tooling for the fabrication of solar cells was in house and evalua...

T. Chao S. Khemthong R. Ling S. Olah

1977-01-01

447

Entanglement Spectrum of Topological Insulators  

NASA Astrophysics Data System (ADS)

Topological order in electronic systems leads to striking features in the ``entanglement spectrum'' which characterizes quantum entanglement between two halves of a system (FDMH, PRL 101,101504 (2008)). If the system is divided along a translationally-invariant boundary, the spectrum can be labeled by momentum parallel to it, and is gapless if topological order is present. The gapless spectrum is related to gapless edge states that appear at free edges of such systems. Topological insulators have non-trivial one-electron band structure properties; the entanglement spectrum of a non-interacting electron Slater determinant state is itself a non-interacting fermionic spectrum. This spectrum is gapped for ``trivial'' ordinary insulating band structures, but exhbits characteristic spectral flow and gapless modes when the band structure is topologically non-trivial. As a case study, the entanglement spectrum of the ``Haldane model'' of a Bloch electron band structure with a zero-field quantum Hall effect will be described in detail, and generalizations to spin-orbit-coupled topological insulators discussed.

Haldane, F. D. M.

2009-03-01

448

Quantifying Mineralization Utilizing Bone Mineral Density Distribution in the Mandible  

PubMed Central

Background Microcomputed Tomography (?CT) is an efficient method for quantifying the density and mineralization of mandibular microarchitecture. Conventional radiomorphometrics such as Bone and Tissue Mineral Density are useful in determining the average, overall mineral content of a scanned specimen; however, solely relying on these metrics has limitations. Utilizing Bone Mineral Density Distribution (BMDD), the complex array of mineralization densities within a bone sample can be portrayed. This information is particularly useful as a computational feature reflective of the rate of bone turnover. Here we demonstrate the utility of BMDD analyses in the rat mandible and generate a platform for further exploration of mandibular pathology and treatment. Methods Male Sprague Dawley rats (n=8) underwent ?CT and histogram data was generated from a selected volume of interest. A standard curve was derived for each animal and reference criteria were defined. An average histogram was produced for the group and descriptive analyses including the means and standard deviations are reported for each of the normative metrics. Results Mpeak (3444 Hounsfield Units, SD =138) and Mwidth (2221 Hounsfield Units SD =628) are two metrics demonstrating reproducible parameters of BMDD with minimal variance. A total of eight valuable metrics quantifying biologically significant events concerning mineralization are reported. Conclusion Here we quantify the vast wealth of information depicted in the complete spectrum of mineralization established by the BMDD analysis. We demonstrate its potential in delivering mineralization data that encompasses and enhances conventional reporting of radiomorphometrics. Moreover, we explore its role and translational potential in craniofacial experimentation.

Donneys, Alexis; Nelson, Noah S.; Deshpande, Sagar S.; Boguslawski, Matthew J.; Tchanque-Fossuo, Catherine N.; Farberg, Aaron S.; Buchman, Steven R.

2012-01-01

449

Is Emotion Recognition Impaired in Individuals with Autism Spectrum Disorders?  

ERIC Educational Resources Information Center

Researchers have argued that individuals with autism spectrum disorders (ASDs) use an effortful "systematizing" process to recognize emotion expressions, whereas typically developing (TD) individuals use a more holistic process. If this is the case, individuals with ASDs should show slower and less efficient emotion recognition, particularly for…

Tracy, Jessica L.; Robins, Richard W.; Schriber, Roberta A.; Solomon, Marjorie

2011-01-01

450

Slotted Random Access Spread-Spectrum Networks: An Analytical Framework  

Microsoft Academic Search

An analytic framework is proposed for the study of singlehop spread-spectrum networks using random access and pack