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Sample records for achieve efficient transmission

  1. Babesia and its hosts: adaptation to long-lasting interactions as a way to achieve efficient transmission

    Chauvin, Alain; Moreau, Emmanuelle; Bonnet, Sarah; Plantard, Olivier; Malandrin, Laurence

    2009-01-01

    Babesia, the causal agent of babesiosis, are tick-borne apicomplexan protozoa. True babesiae (Babesia genus sensu stricto) are biologically characterized by direct development in erythrocytes and by transovarial transmission in the tick. A large number of true Babesia species have been described in various vertebrate and tick hosts. This review presents the genus then discusses specific adaptations of Babesia spp. to their hosts to achieve efficient transmission. The main adaptations lead to ...

  2. High efficiency ground data transmission

    Dickinson, W. B.

    1973-01-01

    It is demonstrated that state-of-the-art communications technology can be implemented and reliably operated on a global basis to increase the transmission rates and efficiencies on circuits with bandwidths greater than the typical speech channel. Optimization is affected by optimum clock recovery procedures, multilevel pulse amplitude modulation, single sideband amplitude modulation, transversal filter equalizers, data scrambling, and active compensation for phase instability.

  3. Analysis of transmission efficiency of SSRF electron beam transfer lines

    2006-01-01

    In this article, the main factors which influence transmission efficiency of the SSRF electron beam transfer lines are described, including physical requirements for magnet system, vacuum system, beam diagnostic system,trajectory correction system, etc. The dynamic simulation calculation and transmission efficiency analysis of the SSRF electron beam transfer lines are presented, and the studies show that the design purpose of efficient beam transmission and injection will be achieved.

  4. Spectrally efficient polymer optical fiber transmission

    Randel, Sebastian; Bunge, Christian-Alexander

    2011-01-01

    The step-index polymer optical fiber (SI-POF) is an attractive transmission medium for high speed communication links in automotive infotainment networks, in industrial automation, and in home networks. Growing demands for quality of service, e.g., for IPTV distribution in homes and for Ethernet based industrial control networks will necessitate Gigabit speeds in the near future. We present an overview on recent advances in the design of spectrally efficient and robust Gigabit-over-SI-POF transmission systems.

  5. Efficiency of Finish power transmission network companies

    The Finnish Energy Market Authority has investigated the efficiency of power transmissions network companies. The results show that the intensification potential of the branch is 402 million FIM, corresponding to about 15% of the total costs of the branch and 7.3 % of the turnout. Energy Market Authority supervises the reasonableness of the power transmission prices, and it will use the results of the research in supervision. The research was carried out by the Quantitative Methods Research Group of Helsinki School of Economics. The main objective of the research was to create an efficiency estimation method for electric power distribution network business used for Finnish conditions. Data of the year 1998 was used as basic material in the research. Twenty-one of the 102 power distribution network operators was estimated to be totally efficient. Highest possible efficiency rate was 100, and the average of the efficiency rates of all the operators was 76.9, the minimum being 42.6

  6. Achievable efficiencies for probabilistically cloning the states

    Gao, Ting; Yan, Fengli; Wang, Zhixi

    2003-01-01

    We present an example of quantum computational tasks whose performance is enhanced if we distribute quantum information using quantum cloning. Furthermore we give achievable efficiencies for probabilistic cloning the quantum states used in implemented tasks for which cloning provides some enhancement in performance.

  7. Achieving affordable housing through energy efficiency strategy

    Cooperation between public and private sector has achieved a remarkable widespread, in the Italian context, over the last two decades. Nevertheless, the increasing difficulty in accessing the capital market and the rising cost of funding sources, both noticeable over the past few years, led to a slowdown of Public–Private Partnership (PPP) initiatives. Meanwhile, the community is expressing new needs to be satisfied, such as the conversion of brownfields, the recovery of housing stock dating back to former times, as well as the refurbishment of public offices or schools. Emerging priorities include the supply of affordable dwellings for low to medium income households. This essay aims to examine a case study in which PPP and buildings energy efficiency have been successfully combined, in order to jointly contribute to the achievement of a social housing settlement. Thanks to energy efficiency measures—concerning building envelope insulation, heating system and other installations—the agreed rent results far higher than social rent of protected tenancies, and furthermore above the range of fair rents characterising other regulated tenancies, but mildly lower than market rents. All this allows to achieve an equity yield rate satisfying from the perspective of a venture philanthropy investment. -- Highlights: •Provision of affordable dwellings is an emerging priority within Italian context. •Lack of public funds leads to promote Public–Private Partnership schemes. •Without public grants the adoption of a venture philanthropy approach is needed. •The examined case study allows to explain the role of buildings energy efficiency. •Buildings energy efficiency may boost feasibility of social housing transactions

  8. Novel infinitely Variable Transmission allowing efficient transmission ratio variations at rest

    Everarts, Christophe; Dehez, Bruno; Ronsse, Renaud; Intelligent Robots and Systems (IROS), 2015 IEEE/RSJ International Conference on

    2015-01-01

    Recent studies showed that Continuously Variable Transmissions (CVT) and Infinitely Variable Transmissions (IVT) can considerably improve the locomotion efficiency in legged robot. A CVT is a transmission whose ratio can be continuously varied and an IVT is a transmission whose ratio can be continuously varied from positive to negative values. However, efficient use of such transmissions in walking applications requires changing the transmission ratio at a minimal energy cost, even at rest, i...

  9. A quantitative analysis of transmission efficiency versus intensity for malaria

    Smith, David L.; Chris J Drakeley; Chiyaka, Christinah; Hay, Simon I.

    2010-01-01

    The relationship between malaria transmission intensity and efficiency is important for malaria epidemiology, for the design of randomized control trials that measure transmission or incidence as end points, and for measuring and modelling malaria transmission and control. Five kinds of studies published over the past century were assembled and reanalysed to quantify malaria transmission efficiency and describe its relation to transmission intensity, to understand the causes of inefficient tr...

  10. Highly Efficient Contactless Electrical Energy Transmission System

    Ayano, Hideki; Nagase, Hiroshi; Inaba, Hiromi

    This paper proposes a new concept for a contactless electrical energy transmission system for an elevator and an automated guided vehicle. The system has rechargeable batteries on the car and electrical energy is supplied at a specific place. When electric power is supplied to the car, it runs automatically and approaches the battery charger. Therefore, a comparatively large gap is needed between the primary transformer at the battery charger and the secondary transformer on the car in order to prevent damage which would be caused by a collision. In this case, a drop of the transformer coupling rate due to the large gap must be prevented. In conventional contactless electrical energy transmission technology, since electric power is received by a pick-up coil from a power line, a large-sized transformer is required. And when the distance over which the car runs is long, the copper loss of the line also increases. The developed system adopts a high frequency inverter using a soft switching method to miniaturize the transformer. The system has a coupling rate of 0.88 for a transformer gap length of 10mm and can operate at 91% efficiency.

  11. Efficient EUV transmission gratings for plasma diagnostics

    Braig, Christoph; Kley, Ernst-Bernhard

    2010-07-01

    We report on a theoretical study of binary phase transmission gratings for high-resolution EUV and soft X-ray spectroscopy and investigate their optical properties. Designed for wavelengths between about 2 and 40 nm, the devices may provide a first order diffraction efficiency beyond 30%. We use RCWA methods in order to optimize the grating design parameters and discuss special features of segmented grating arrays. Several elemental as well as compound materials like Be, Mo, LiF and PMMA are considered with respect to their potential and practical limitations in terms of feasibility and sensitivity to radiation damage. Simulations are performed for several samples on the radiation produced by a table-top EUV plasma source and applications to astrophysical problems are considered.

  12. Punctured Turbo Codes for Bandwidth-efficient Transmission

    Shobha Rekh

    2006-10-01

    Full Text Available Turbo codes are the error-coding schemes applied nowadays in wireless networks. In navalapplications, the information is mostly sent through wireless networks and the data is moreprone to noise. Since very important data has to be communicated, it is necessary to get backthe original data in the receiver. In military applications also, the soldiers wear electronic jacketswhich are connected by wireless networks. In such applications, the data loss is not affordableand there is also a need to utilise the bandwidth efficiently through puncturing by means ofwhich certain bits are deleted before transmission from the output of encoder. By means of thispunctured turbo codes, bandwidth-efficient coding is achieved. Hence, it is necessary to designturbo codes with an efficient puncturing pattern so that the performance of the punctured codeis also improved in spite of deletion of few bits before transmission. This paper deals in choosingthe puncturing patterns that lead to systematic rate-compatible punctured turbo codes (RCPTCswhich also give a reduction in bit-error rate. The design criterion for choosing the best puncturingpatterns is based on the minimum weight of code words and their multiplicities. The best puncturingpattern chosen is tested for its performance by simulating turbo codes for an additive whiteGaussian noise (AWGN channel. Compared with the existing puncturing pattern, the patternproposed is able to achieve a gain of 0.5 dB at a bit-error rate of 10-3.

  13. Simulation Study on Coil Design of Wireless Power Transfer System for Optimal Transmission Efficiency

    Hao Qiang

    2013-05-01

    Full Text Available As an emerging research field, Wireless Power Transfer (WPT has attracted wide spread attention recently. In this study, the coil design of WPT system for optimal transmission efficiency is investigated. We deduce Tthe design criteria are deduced to meet various conditions of transmission distance and load. The results of simulation and experiment show the transmission efficiency from transmitting coil to receiving coil can keep high when the corresponding optimal condition is achieved. Thusen it can improve the overall transmission efficiency of the WPT system and it makes it suitable for the practical application of WPT system.

  14. Achieving Energy Efficiency Through Real-Time Feedback

    Nesse, Ronald J.

    2011-09-01

    Through the careful implementation of simple behavior change measures, opportunities exist to achieve strategic gains, including greater operational efficiencies, energy cost savings, greater tenant health and ensuing productivity and an improved brand value through sustainability messaging and achievement.

  15. Achieving Energy Efficient Ship Operations Under Third Party Management

    Taudal Poulsen, René; Sornn-Friese, Henrik

    2015-01-01

    Profitable energy saving measures are often not fully implemented in shipping, causing energy efficiency gaps. The paper identifies energy efficiency gaps in ship operations, and explores their causes. Lack of information on energy efficiency, lack of energy training at sea and onshore and lack...... of time to produce and provide reliable energy efficiency information cause energy efficiency gaps. The paper brings together the energy efficiency and ship management literatures, demonstrating how ship management models influence energy efficiency in ship operations. Achieving energy efficiency in ship...... operations is particularly challenging under third party ship management. Finally, the paper discusses management implications for shipping companies, which outsource ship management to third parties....

  16. Parenting and Academic Achievement: Intergenerational Transmission of Educational Advantage

    Roksa, Josipa; Potter, Daniel

    2011-01-01

    A growing body of research has examined how cultural capital, recently broadened to include not only high-status cultural activities but also a range of different parenting practices, influences children's educational success. Most of this research assumes that parents' current class location is the starting point of class transmission. However,…

  17. Energy-Efficient Data Transmission with Non-FIFO Packets

    Zhou, Qing; Liu, Nan

    2015-01-01

    This paper investigates the problem of energy-efficient packet transmission with arbitrary arrival instants and deadline constraints over a point-to-point Additive White Gaussian Noise (AWGN) channel. This is different from previous work where it is assumed that the packets follow a First-In-First-Out (FIFO) order in that the packets that arrive earlier will have a deadline that is also earlier. We first investigate the necessary and sufficient conditions of the optimal transmission scheduler...

  18. Hydraulic efficiency of a hydrostatic transmission with a variable displacement pump and motor

    Coombs, Daniel

    Pumps and motors are commonly connected hydraulically to create hydrostatic drives, also known as hydrostatic transmissions. A typical hydrostatic transmission consists of a variable displacement pump and a fixed displacement motor. Maximum efficiency is typically created for the system when the motor operates at maximum volumetric displacement. The objective of this research is to determine if a hydrostatic transmission with a variable displacement motor can be more efficient than one with a fixed displacement motor. A work cycle for a Caterpillar 320D excavator was created and the efficiency of the hydrostatic drive system, controlling the swing circuit, with a fixed displacement motor was compared to the efficiency with a variable displacement motor. Both multiplicative and additive uncertainty analysis were performed to determine uncertainty models that could be used to analyze the robustness of the system with feedback control applied. A PID and an H∞ controller were designed for a position control model, as well as velocity control. It was found that while it may seem obvious to achieve maximum efficiency at maximum displacement, there are some cases where maximum efficiency is achieved at a lower displacement. It was also found that for the given work cycle, a hydrostatic transmission with a variable displacement motor can be more efficient.

  19. Efficient Dynamic Compressor Optimization in Natural Gas Transmission Systems

    Mak, Terrence W. K.; Van Hentenryck, Pascal; Zlotnik, Anatoly; Hijazi, Hassan; Bent, Russell

    2015-01-01

    The growing reliance of electric power systems on gas-fired generation to balance intermittent sources of renewable energy has increased the variation and volume of flows through natural gas transmission pipelines. Adapting pipeline operations to maintain efficiency and security under these new conditions requires optimization methods that account for transients and that can quickly compute solutions in reaction to generator re-dispatch. This paper presents an efficient scheme to minimize com...

  20. ENERGY EFFICIENCY OF DIESEL LOCOMOTIVE HYDRAULIC TRANSMISSION TESTS AT LOCOMOTIVE REPAIR PLANT

    B. E. Bodnar

    2015-10-01

    Full Text Available Purpose. In difficult economic conditions, cost reduction of electricity consumption for the needs of production is an urgent task for the country’s industrial enterprises. Technical specifications of enterprises, which repair diesel locomotive hydraulic transmission, recommend conducting a certain amount of evaluation and regulatory tests to monitor their condition after repair. Experience shows that a significant portion of hydraulic transmission defects is revealed by bench tests. The advantages of bench tests include the ability to detect defects after repair, ease of maintenance of the hydraulic transmission and relatively low labour intensity for eliminating defects. The quality of these tests results in the transmission resource and its efficiency. Improvement of the technology of plant post-repairs hydraulic tests in order to reduce electricity consumption while testing. Methodology. The possible options for hydraulic transmission test bench improvement were analysed. There was proposed an energy efficiency method for diesel locomotive hydraulic transmission testing in locomotive repair plant environment. This is achieved by installing additional drive motor which receives power from the load generator. Findings. Based on the conducted analysis the necessity of improving the plant stand testing of hydraulic transmission was proved. The variants of the stand modernization were examined. The test stand modernization analysis was conducted. Originality. The possibility of using electric power load generator to power the stand electric drive motor or the additional drive motor was theoretically substantiated. Practical value. A variant of hydraulic transmission test stand based on the mutual load method was proposed. Using this method increases the hydraulic transmission load range and power consumption by stand remains unchanged. The additional drive motor will increase the speed of the input shaft that in its turn wil allow testing in

  1. Efficient Real-time Video Transmission in Wireless Mesh Network

    Rajanikanth Aluvalu

    2011-12-01

    Full Text Available We are experiencing rapid improvement in video transmission and picture quality. The technologies are supporting us with real-time video transmissions such as video conferences and webinars. Soon reliable, simple, low cost real-time video will become essential, providing its extensive support to mobiles; PDA’s etc. These enhancements are going to affect the consumer behaviour, business culture. Video transmission includes transmitting packets through Wireless Mesh Network (WMN, which turned out to be a challenging scenario for real-time video services. Due to the existing nature of wireless networks include the presence of unpredictable delays and high packet error rates due to the error-prone nature of the wireless links. In this paper, we will propose a model which provides high capacity data transfer with reduced delay. We have simulated and achieved results with higher through put.

  2. Optimizing link efficiency for gated DPCCH transmission on HSUPA

    Zarco, Carlos Ruben Delgado; Wigard, Jeroen; Kolding, T. E.;

    2007-01-01

    link efficiency (LE) perspective; LE being expressed in bits per second per Watt. While the overall gain mechanisms of gating are well known, we show how special challenges related to discontinuous Enhanced Dedicated Channel (E-DCH) transmission can be addressed for high link and system performance. We......To minimize the terminal's transmission power in bursty uplink traffic conditions, the evolved High-Speed Uplink Packet Access (HSUPA) concept in 3GPP WCDMA includes a feature known as Dedicated Physical Control Channel (DPCCH) gating. We present here a detailed link level study of gating from a...... consider the E-DCH performance degradation caused by gating on other radio procedures relying on the DPCCH, such as inner and outer loop power control. Our studies show that gating is beneficial for both for 2 and 10 ms transmission time intervals. The gains in terms of LE with a Vehicular A 30 kmph...

  3. Efficient incremental relaying for packet transmission over fading channels

    Fareed, Muhammad Mehboob

    2014-07-01

    In this paper, we propose a novel relaying scheme for packet transmission over fading channels, which improves the spectral efficiency of cooperative diversity systems by utilizing limited feedback from the destination. Our scheme capitalizes on the fact that relaying is only required when direct transmission suffers deep fading. We calculate the packet error rate for the proposed efficient incremental relaying (EIR) scheme with both amplify and forward and decode and forward relaying. We compare the performance of the EIR scheme with the threshold-based incremental relaying (TIR) scheme. It is shown that the efficiency of the TIR scheme is better for lower values of the threshold. However, the efficiency of the TIR scheme for higher values of threshold is outperformed by the EIR. In addition, three new threshold-based adaptive EIR are devised to further improve the efficiency of the EIR scheme. We calculate the packet error rate and the efficiency of these new schemes to provide the analytical insight. © 2014 IEEE.

  4. A New Electrospray Aerosol Generator with High Particle Transmission Efficiency.

    Fu, Huijing; Patel, Anand C; Holtzman, Michael J; Chen, Da-Ren

    2011-01-01

    A new single-capillary electrospray (ES) aerosol generator has been developed for monodisperse particle production with maximal transmission efficiency. The new generator consists of both a spray chamber in a point-to-orifice-plate configuration and a charge reduction chamber that can hold up to 4 Nuclespot ionizers (Model P-2042, NRD Inc.). The 2 chambers are partitioned by an orifice plate. To optimize the particle transmission efficiency of the prototype, a systematic study was performed on the generator by varying the system setup and operation. Two key dimensions of the generator setup, the orifice diameter and the distance from the capillary tip to the orifice plate, were varied. Fluorescence analysis was applied to characterize the loss of ES-generated particles at different locations of the prototype. It was found that particle loss in the generator could be reduced by either increasing the orifice diameter or decreasing the distance between the capillary tip and the orifice plate. Increasing either the total radioactivity of the ionizers or the flowrate of the particle carrier gas also further decreased the particle loss in the system. The maximum particle transmission efficiency of 88.0% was obtained with the spray chamber fully opened to the charge reduction chamber, the capillary tip at the same level as the orifice plate, and 4 bipolar ionizers installed. PMID:22829715

  5. Highly polarized and high quantum efficiency electron source using transmission-type photocathode

    Recently, we developed transmission-type spin polarized photocathodes (PCs). In the development, a commercially available GaP wafer with high Zn doping of 1.4 x 1017 cm-3 was employed instead of a GaAs substrate because that is transparent for 780-nm excitation laser light. In the early phase of the development, both of the electron spin polarization and quantum efficiency were relatively lower than conventional reflection-type PCs. Nowadays, the electron spin polarization of ∼90% and quantum efficiency of 0.4% was already achieved simultaneously using the transmission PC with GaAs-GaAsP strained superlattice layers. We are making further R and D to improve it's quantum efficiency and further experiments such as generation of short pulse beam are scheduled. (author)

  6. Nanofabrication advances for high efficiency critical-angle transmission gratings

    Bruccoleri, Alexander R.; Guan, Dong; Heilmann, Ralf K.; Vargo, Steve; DiPiazza, Frank; Schattenburg, Mark L.

    2013-09-01

    We report several break-through nanofabrication developments enabling high efficiency and high resolving power spectrometers in the soft x-ray band. The device is the critical-angle transmission (CAT) grating, which combines the low mass and relaxed alignment tolerances of a transmission grating with the high broad-band efficiency and high diffraction orders of a blazed reflection grating. Past work successfully demonstrated the CAT grating concept; however, the open-area fraction was often less than 20% whilst more than 50% is desired. This presents numerous nanofabrication challenges including a requirement for a freestanding silicon membrane of ultra high-aspect ratio bars at a period of 200 nanometers with minimal cross support blockage. Furthermore, the sidewalls must be smooth to a few nanometers to efficiently reflect soft x-rays. We have developed a complete nanofabrication process for creating freestanding CAT gratings via plasma-etching silicon wafers with a buried layer of SiO2. This removable buried layer enables combining a record-performance plasma etch for the CAT grating with a millimeter-scale honeycomb structural support to create a large-area freestanding membrane. We have also developed a process for polishing sidewalls of plasma-etched ultra-high aspect ratio nanoscale silicon structures via potassium hydroxide (KOH). This process utilizes the anisotropic etch nature of single crystal silicon in KOH. We developed a novel alignment technique to align the CAT grating bars to the {111} planes of silicon within 0.2 degrees, which enables KOH to etch away sidewall roughness without destroying the structure, since the {111} planes etch approximately 100 times slower than the non-{111} planes. Preliminary results of a combined freestanding grating with polishing are presented to enable efficient diffraction of soft x-rays.

  7. A Secure Protocol for Efficient SMS Transmission and Management

    Lianju Ning

    2013-09-01

    Full Text Available Recently, the usage of mobile phones around the world is growing more and more. Short Message Service (SMS is one of the most important applications due to its easy way to send and receive messages from users to users. There have been many transmission protocols aiming to make sure secure and effective transferring in the SMS. Some of them are based on symmetric algorithms, while others are based on signature encryption or public key infrastructure. However, all of these existing protocols lack sufficient security or high efficiency. When the protocols possess high security margin, they usually have a limited performance in software. And when the performance is guaranteed, the security margin usually decreases. So in this paper, we study the advantages and disadvantages of some widely-used protocols. Basing on this, we propose a new protocol for secure SMS transmission. Our protocol improves both the structure and the modules of previous protocols from theoretical and practical aspects, so that it can assure the security level as well as very efficient performance. Compared with other protocols having similar security, our protocol has a more convenient implementation. Compared with other protocols with similar performance, our protocol is safer. Also, we use a signature model which does not need the PKI on-line, increasing the security greatly. Finally, we take experiments on real mobile phones to verify our protocol and analyze the results.

  8. A collimated focused ultrasound beam of high acoustic transmission and minimum diffraction achieved by using a lens with subwavelength structures

    Lin, Zhou; Tu, Juan; Cheng, Jianchun [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); Guo, Xiasheng, E-mail: guoxs@nju.edu.cn, E-mail: dzhang@nju.edu.cn [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Wu, Junru [Department of Physics, University of Vermont, Burlington, Vermont 05405 (United States); Huang, Pingtong [Department of Ultrasound, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310009 (China); Zhang, Dong, E-mail: guoxs@nju.edu.cn, E-mail: dzhang@nju.edu.cn [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); The State Key Laboratory of Acoustics, Chinese Academy of Science, Beijing 10080 (China)

    2015-09-14

    An acoustic focusing lens incorporated with periodically aligned subwavelength grooves corrugated on its spherical surface has been developed. It is demonstrated theoretically and experimentally that acoustic focusing achieved by using the lens can suppress the relative side-lobe amplitudes, enhance the focal gain, and minimize the shifting of the focus. Use of the lens coupled with a planar ultrasound transducer can generate an ultrasound beam with enhanced acoustic transmission and collimation effect, which offers the capability of improving the safety, efficiency, and accuracy of targeted surgery implemented by high intensity focused ultrasound.

  9. A collimated focused ultrasound beam of high acoustic transmission and minimum diffraction achieved by using a lens with subwavelength structures

    An acoustic focusing lens incorporated with periodically aligned subwavelength grooves corrugated on its spherical surface has been developed. It is demonstrated theoretically and experimentally that acoustic focusing achieved by using the lens can suppress the relative side-lobe amplitudes, enhance the focal gain, and minimize the shifting of the focus. Use of the lens coupled with a planar ultrasound transducer can generate an ultrasound beam with enhanced acoustic transmission and collimation effect, which offers the capability of improving the safety, efficiency, and accuracy of targeted surgery implemented by high intensity focused ultrasound

  10. Quality assurance: the management route to achieve efficiency and competitiveness

    Quality Assurance (QA) requires total integration and control of all elements within a particular area of operation so that none is subservient to the others. These elements cover such aspects as administration, design, procurement, manufacture, installation and commissioning. The responsibility for the establishment of requirements and the integration and control of all activities should therefore be assigned to a certain person. Ultimately it is the senior executive of an organization who must accept responsibility for the above mentioned direction and for the quality of the items or services produced by his company. QA is therefore a management function which cannot be delegated. The philosophy and the concept are highlighted of QA as a management tool and a route to achieve efficiency and competitiveness. (author). 2 figs., 7 refs

  11. An Efficient Medium Access Control Protocol with Parallel Transmission for Wireless Sensor Networks

    Mitsuji Matsumoto

    2012-08-01

    Full Text Available In this paper, we present a novel low power medium access control protocol for wireless sensor networks (WSNs. The proposed protocol, EP-MAC (Efficient MAC with Parallel Transmission achieves high energy efficiency and high packet delivery ratio under different traffic load. EP-MAC protocol is basically based on the Time Division Multiple Access (TDMA approach. The power of Carrier Sense Multiple Access (CSMA is used in order to offset the fundamental problems that the stand-alone TDMA method suffers from, i.e., problems such as lack of scalability, adaptability to varying situations, etc. The novel idea behind the EP-MAC is that it uses the parallel transmission concept with the TDMA link scheduling. EP-MAC uses the methods for the transmission power adjustment, i.e., uses the minimum level power necessary to reach the intended neighbor within a specified bit error rate [BER] target. This reduces energy consumption, as well as further enhances the scope of parallel transmission of the protocol. The simulation studies support the theoretical results, and validate the efficiency of our proposed EP-MAC protocol.

  12. Achieving energy efficiency through behaviour change: what does it take?

    Barbu, A.-D. [European Environment Agency (EEA), Copenhagen (Denmark); Griffiths, N.; Morton, G. [Ricardo-AEA (United Kingdom)

    2013-04-15

    On October 2012, the European Union adopted the Energy Efficiency Directive in reaction to the fact that EU Member States were not on track to reduce primary energy consumption by 20 % by 2020. The implementation of this directive, and other policies that have been adopted in recent years, will require a change in consumer behaviour and energy consumption practices. Within this context, and related to on-going debates on the same subject, a new European Environment Agency (EEA) report argues that correctly navigating the interface between policymaking and human behaviour is key to achieving sustained reductions in energy consumption. As such, the report provides timely and reliable information and analysis to those involved in designing policy measures to reduce energy consumption which target the end consumer. A growing body of evidence in academic literature demonstrates that there is potential for energy savings due to measures targeting behaviour. There is, however, one issue that has not been covered by previous studies, and which the EEA report directly addresses, namely the distinction between consumer behaviour and consumption practices. Most recent academic literature argues that it is the consumption practices themselves that need careful scrutiny as they tend to lock consumers into patterns that are more and more energy intensive and they involve a wide range of actors. From the energy efficiency policy design perspective, this is relevant because these actors need to be involved from the outset of the policy process. The report also argues that a whole range of changes need to take place in the way energy markets function and are regulated in order to enable the consumer to actively engage with these markets. The report however does not include a discussion on the socio-economic implications of these structural changes. During 2013, the EEA will launch a survey via social media and its own website to follow up on conclusions of the report. The aim will

  13. Energy efficient downlink MIMO transmission with linear precoding

    XU Jie; LI ShiChao; QIU Ling; SLIMANE Ben S.; YU ChengWen

    2013-01-01

    Energy efficiency (EE) is becoming increasingly important for wireless cellular networks. This paper addresses EE optimization problems in downlink multiuser MIMO systems with linear precoding. Referring to different active transmit/receive antenna sets and transmission schemes as different modes, we propose a joint bandwidth/power optimization and mode switching scheme to maximize EE. With a specific mode, we prove that the optimal bandwidth and transmit power is either full transmit power or full bandwidth. After deriving the optimal bandwidth and transmit power, we further propose mode switching to select the mode with optimal EE. Since the optimal mode switching, i.e. exhaustive search, is too complex to implement, an alternative heuristic method is developed to decrease the complexity through reducing the search size and avoiding the EE calculation during each search. Through simulations, we demonstrate that the proposed methods can significantly improve EE and the performance is similar to the optimal exhaustive search.

  14. Efficient extreme ultraviolet transmission gratings for plasma diagnostics

    Braig, Christoph; Predehl, Peter; Kley, Ernst-Bernhard

    2011-06-01

    We report on a theoretical study of free-standing phase transmission gratings for high-resolution extreme ultraviolet (EUV) and soft x-ray spectroscopy and investigate their properties. Designed for wavelengths between about 2 and 40 nm, the devices may provide a first order diffraction efficiency beyond 30%. We use rigorous coupled wave analysis methods in order to optimize the grating design parameters and discuss features of segmented grating arrays. Elemental, as well as compound, materials such as Be, Mo, LiF, and poly-(methylmethacrylate) are considered with respect to their potential and practical limitations in terms of feasibility and sensitivity to radiation damage. Simulations are performed for several samples on the radiation produced by a table-top EUV plasma source and applications to astrophysical problems are considered.

  15. Novel efficient and secure medical data transmission on WiMAX.

    Kumar, Basant; Singh, Harsh Vikram; Singh, S P; Mohan, Anand

    2008-12-01

    This paper discusses an improved technique for bandwidth-efficient and secure transmission of medical records over simulated orthogonal frequency division multiplexing (OFDM)-based Worldwide Interoperability for Microwave Access (WiMAX)/IEEE 802.16 physical layer. Medical data compaction along with security has been achieved by embedding electrocardiogram (ECG) data into Haar wavelet coefficients of an x-ray image that is transmitted over the channel. The compaction ratio and peak signal-to-noise ratio (PSNR) between the transmitted and received x-ray images for visual clinical performance have been evaluated. It is shown that 12.5% data compaction along with true reception of ECG signal can be achieved for channel signal-to-noise ratio (SNR) >or= 9.6 dB while the achieved PSNR was 55.97 dB. The PSNR value is well above the minimum acceptable 35 dB level, making it potentially useful for secure and bandwidth-efficient transmission of clinical records. PMID:19119828

  16. Fusing electromagnetic one-way edge states to achieve broadband unidirectional wave transmission

    There exist two types of electromagnetic (EM) one-way edge states in magnetic photonic crystal (MPC). One is associated with photonic band gap (PBG) relevant to Bragg scattering, while the other is associated with PBG originating from magnetic surface plasmon resonance. Both support robust unidirectional wave transmission, but each with relatively limited operating bandwidth. By optimizing the lattice spacing and filling ratio of MPC as well as tuning the external static biasing magnetic field, we are able to fuse the two types of EM one-way edge states together and therefore achieve broadband one-way transmission. The operating bandwidth could be about 4 GHz in a microwave regime; this is much larger than that based on either type, providing a way towards the practical applications of unidirectional wave propagation. (paper)

  17. Theoretical Analysis of Measurement in Operation Efficiency in Optical Cable Transmission Networks

    2000-01-01

    It is necessary to study dynamic operation efficiency of transmission networks in order to realize high intensification of communication networks. The operation efficiency discussed here should exist not only in logic-circuit layer, but also in both path layer and medium layer. A theoretical method of the measurement of layers and comprehensive evaluations is presented based on the concept of transmission efficiency.

  18. Interference mitigation for broadcast in hierarchical cell structure networks: Transmission strategy and area spectral efficiency

    Yang, Yuli

    2014-10-01

    In this paper, a hierarchical cell structure (HCS) is considered, where an access point (AP) broadcasts to local nodes (LNs) over orthogonal frequency subbands within a local cell located in a macrocell. Since the local cell shares the spectrum licensed to the macrocell, a given LN is interfered with by the macrocell user (MU)\\'s transmissions over the same subband. To improve the performance of the AP\\'s broadcast service, a novel transmission strategy is proposed to mitigate the interference from the MU to the LN while achieving diversity gain. For the purpose of performance evaluation, the ergodic capacity of the proposed scheme is quantified, and the corresponding closed-form expression is obtained. By comparing with the traditional transmission scheme, which suffers from MU\\'s interference, illustrative numerical results substantiate that the proposed scheme achieves better performance than the traditional scheme as the MU-LN mean channel power gain is larger than half of the AP-LN mean channel power gain. Subsequently, we develop an optimized network design by maximizing the area spectral efficiency (ASE) of the AP\\'s broadcast in the local cell.

  19. First Eigenmode Transmission by High Efficient CSI Estimation for Multiuser Massive MIMO Using Millimeter Wave Bands.

    Maruta, Kazuki; Iwakuni, Tatsuhiko; Ohta, Atsushi; Arai, Takuto; Shirato, Yushi; Kurosaki, Satoshi; Iizuka, Masataka

    2016-01-01

    Drastic improvements in transmission rate and system capacity are required towards 5th generation mobile communications (5G). One promising approach, utilizing the millimeter wave band for its rich spectrum resources, suffers area coverage shortfalls due to its large propagation loss. Fortunately, massive multiple-input multiple-output (MIMO) can offset this shortfall as well as offer high order spatial multiplexing gain. Multiuser MIMO is also effective in further enhancing system capacity by multiplexing spatially de-correlated users. However, the transmission performance of multiuser MIMO is strongly degraded by channel time variation, which causes inter-user interference since null steering must be performed at the transmitter. This paper first addresses the effectiveness of multiuser massive MIMO transmission that exploits the first eigenmode for each user. In Line-of-Sight (LoS) dominant channel environments, the first eigenmode is chiefly formed by the LoS component, which is highly correlated with user movement. Therefore, the first eigenmode provided by a large antenna array can improve the robustness against the channel time variation. In addition, we propose a simplified beamforming scheme based on high efficient channel state information (CSI) estimation that extracts the LoS component. We also show that this approximate beamforming can achieve throughput performance comparable to that of the rigorous first eigenmode transmission. Our proposed multiuser massive MIMO scheme can open the door for practical millimeter wave communication with enhanced system capacity. PMID:27399715

  20. Distributed Space-Time Block Coded Transmission with Imperfect Channel Estimation: Achievable Rate and Power Allocation

    Sonia Aïssa

    2008-05-01

    Full Text Available This paper investigates the effects of channel estimation error at the receiver on the achievable rate of distributed space-time block coded transmission. We consider that multiple transmitters cooperate to send the signal to the receiver and derive lower and upper bounds on the mutual information of distributed space-time block codes (D-STBCs when the channel gains and channel estimation error variances pertaining to different transmitter-receiver links are unequal. Then, assessing the gap between these two bounds, we provide a limiting value that upper bounds the latter at any input transmit powers, and also show that the gap is minimum if the receiver can estimate the channels of different transmitters with the same accuracy. We further investigate positioning the receiving node such that the mutual information bounds of D-STBCs and their robustness to the variations of the subchannel gains are maximum, as long as the summation of these gains is constant. Furthermore, we derive the optimum power transmission strategy to achieve the outage capacity lower bound of D-STBCs under arbitrary numbers of transmit and receive antennas, and provide closed-form expressions for this capacity metric. Numerical simulations are conducted to corroborate our analysis and quantify the effects of imperfect channel estimation.

  1. Secure and Efficient Data Transmission over Body Sensor and Wireless Networks

    Challa Narasimha

    2008-01-01

    Full Text Available Abstract This paper addresses the transmission of medical and context-aware data from mobile patients to healthcare centers over heterogeneous wireless networks. A handheld device, called personal wireless hub (PWH, of each mobile patient first gathers and aggregates the vital sign and context-aware data for various telemedicine applications. PWH transmits the aggregated data to the remote healthcare center over multiple wireless interfaces such as cellular, WLAN, and WiMAX. The aggregated data contain both periodic data and those nonperiodic unpredictable emergency messages that are sporadic and delayintolerant. This paper addresses the problem of providing QoS (e.g., minimum delay, sufficient data rate, acceptable blocking, and/or dropping rate by designing a packet scheduling and channel/network allocation algorithm over wireless networks. The proposed resource-efficient QoS mechanism is simple and collaborates with an adaptive security algorithm. The QoS and security are achieved mainly with the collaboration of differentiator, delay monitor, data classifier, and scheduler modules within the PWH. This paper also discusses secure data transmission over body sensor networks by introducing key establishment and management algorithms. Simulation results show that the proposed framework achieves low-blocking probability, meets delay requirements, and provides energy-efficient secure communication for the combination of vital signs and context-aware data.

  2. Secure and Efficient Data Transmission over Body Sensor and Wireless Networks

    Madhur Sikri

    2008-09-01

    Full Text Available This paper addresses the transmission of medical and context-aware data from mobile patients to healthcare centers over heterogeneous wireless networks. A handheld device, called personal wireless hub (PWH, of each mobile patient first gathers and aggregates the vital sign and context-aware data for various telemedicine applications. PWH transmits the aggregated data to the remote healthcare center over multiple wireless interfaces such as cellular, WLAN, and WiMAX. The aggregated data contain both periodic data and those nonperiodic unpredictable emergency messages that are sporadic and delayintolerant. This paper addresses the problem of providing QoS (e.g., minimum delay, sufficient data rate, acceptable blocking, and/or dropping rate by designing a packet scheduling and channel/network allocation algorithm over wireless networks. The proposed resource-efficient QoS mechanism is simple and collaborates with an adaptive security algorithm. The QoS and security are achieved mainly with the collaboration of differentiator, delay monitor, data classifier, and scheduler modules within the PWH. This paper also discusses secure data transmission over body sensor networks by introducing key establishment and management algorithms. Simulation results show that the proposed framework achieves low-blocking probability, meets delay requirements, and provides energy-efficient secure communication for the combination of vital signs and context-aware data.

  3. Achievable Rates of Secure Transmission in Gaussian MISO Channel with Imperfect Main Channel Estimation

    Zhou, Xinyu

    2016-03-15

    A Gaussian multiple-input single-output (MISO) fading channel is considered. We assume that the transmitter, in addition to the statistics of all channel gains, is aware instantaneously of a noisy version of the channel to the legitimate receiver. On the other hand, the legitimate receiver is aware instantaneously of its channel to the transmitter, whereas the eavesdropper instantaneously knows all channel gains. We evaluate an achievable rate using a Gaussian input without indexing an auxiliary random variable. A sufficient condition for beamforming to be optimal is provided. When the number of transmit antennas is large, beamforming also turns out to be optimal. In this case, the maximum achievable rate can be expressed in a simple closed form and scales with the logarithm of the number of transmit antennas. Furthermore, in the case when a noisy estimate of the eavesdropper’s channel is also available at the transmitter, we introduce the SNR difference and the SNR ratio criterions and derive the related optimal transmission strategies and the corresponding achievable rates.

  4. Air Force Achieves Fuel Efficiency through Industry Best Practices

    None

    2012-12-01

    The U.S. Air Force’s Air Mobility Command (AMC) is changing the way it does business. It is saving energy and money through an aircraft fleet fuel-efficiency program inspired by private industry best practices and ideas resulting from the empowered fuel savings culture.

  5. Achieving energy efficiency through product policy: the UK experience

    The focus of this paper is on energy efficiency of domestic equipment. It is contended that, in the UK and--by extension--elsewhere. Government has to take the lead in defining low-energy standards for products. In the absence of policy, manufacturers do not recognize the need for carbon reductions in the equipment they design and consumers are unaware of the variation in energy performance in the product range. At present, neither market pull nor technology push can be relied upon to deliver energy savings. The imposition of a weak minimum standard on domestic fridges and freezers in 1999 will, over the lifetime of the appliances already sold by December 2002, save 1 Mt C of carbon dioxide at nil cost to government or to the manufacturers, and a net benefit to consumers of pound 855 m: a highly cost-effective policy. The difference between energy efficiency and energy conservation is that it takes time for the cumulative benefits of an energy efficiency improvement to result in the maximum effect on energy demand reduction: the benefits of the 1999 energy efficiency standard will accumulate until at least 2020. This period is equivalent to the cycle of stock replacement for that particular object. The final level of energy conservation depends upon the offsetting effects of growth in ownership levels and the size of new equipment purchases

  6. Achieving energy efficiency through product policy: the UK experience

    Boardman, Brenda

    2004-06-01

    The focus of this paper is on energy efficiency of domestic equipment. It is contended that, in the UK and--by extension--elsewhere. Government has to take the lead in defining low-energy standards for products. In the absence of policy, manufacturers do not recognize the need for carbon reductions in the equipment they design and consumers are unaware of the variation in energy performance in the product range. At present, neither market pull nor technology push can be relied upon to deliver energy savings. The imposition of a weak minimum standard on domestic fridges and freezers in 1999 will, over the lifetime of the appliances already sold by December 2002, save 1 Mt C of carbon dioxide at nil cost to government or to the manufacturers, and a net benefit to consumers of pound 855 m: a highly cost-effective policy. The difference between energy efficiency and energy conservation is that it takes time for the cumulative benefits of an energy efficiency improvement to result in the maximum effect on energy demand reduction: the benefits of the 1999 energy efficiency standard will accumulate until at least 2020. This period is equivalent to the cycle of stock replacement for that particular object. The final level of energy conservation depends upon the offsetting effects of growth in ownership levels and the size of new equipment purchases.

  7. High-Efficiency All-Dielectric Metasurfaces for Ultracompact Beam Manipulation in Transmission Mode.

    Shalaev, Mikhail I; Sun, Jingbo; Tsukernik, Alexander; Pandey, Apra; Nikolskiy, Kirill; Litchinitser, Natalia M

    2015-09-01

    Metasurfaces are two-dimensional structures enabling complete control on light amplitude, phase, and polarization. Unlike plasmonic metasurfaces, silicon structures facilitate high transmission, low losses, and compatibility with existing semiconductor technologies. We experimentally demonstrate two examples of high-efficiency polarization-sensitive dielectric metasurfaces with 2π phase control in transmission mode (45% transmission efficiency for the vortex converter and 36% transmission efficiency for the beam steering device) at telecommunication wavelengths. Silicon metasurfaces are poised to enable a versatile platform for the realization of all-optical circuitry on a chip. PMID:26280735

  8. Telescoping Solar Array Concept for Achieving High Packaging Efficiency

    Mikulas, Martin; Pappa, Richard; Warren, Jay; Rose, Geoff

    2015-01-01

    Lightweight, high-efficiency solar arrays are required for future deep space missions using high-power Solar Electric Propulsion (SEP). Structural performance metrics for state-of-the art 30-50 kW flexible blanket arrays recently demonstrated in ground tests are approximately 40 kW/cu m packaging efficiency, 150 W/kg specific power, 0.1 Hz deployed stiffness, and 0.2 g deployed strength. Much larger arrays with up to a megawatt or more of power and improved packaging and specific power are of interest to mission planners for minimizing launch and life cycle costs of Mars exploration. A new concept referred to as the Compact Telescoping Array (CTA) with 60 kW/cu m packaging efficiency at 1 MW of power is described herein. Performance metrics as a function of array size and corresponding power level are derived analytically and validated by finite element analysis. Feasible CTA packaging and deployment approaches are also described. The CTA was developed, in part, to serve as a NASA reference solar array concept against which other proposed designs of 50-1000 kW arrays for future high-power SEP missions could be compared.

  9. 10 CFR 433.7 - Water used to achieve energy efficiency. [Reserved

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Water used to achieve energy efficiency. 433.7 Section 433.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR THE DESIGN AND... achieve energy efficiency....

  10. Characterization of the mass-dependent transmission efficiency of a CIMS

    Heinritzi, Martin; Simon, Mario; Steiner, Gerhard; Wagner, Andrea C.; Kürten, Andreas; Hansel, Armin; Curtius, Joachim

    2016-04-01

    Knowledge about mass discrimination effects in a chemical ionization mass spectrometer (CIMS) is crucial for quantifying, e.g., the recently discovered extremely low volatile organic compounds (ELVOCs) and other compounds for which no calibration standard exists so far. Here, we present a simple way of estimating mass discrimination effects of a nitrate-based chemical ionization atmospheric pressure interface time-of-flight (CI-APi-TOF) mass spectrometer. Characterization of the mass discrimination is achieved by adding different perfluorinated acids to the mass spectrometer in amounts sufficient to deplete the primary ions significantly. The relative transmission efficiency can then be determined by comparing the decrease of signals from the primary ions and the increase of signals from the perfluorinated acids at higher masses. This method is in use already for PTR-MS; however, its application to a CI-APi-TOF brings additional difficulties, namely clustering and fragmentation of the measured compounds, which can be treated with statistical analysis of the measured data, leading to self-consistent results. We also compare this method to a transmission estimation obtained with a setup using an electrospray ion source, a high-resolution differential mobility analyzer and an electrometer, which estimates the transmission of the instrument without the CI source. Both methods give different transmission curves, indicating non-negligible mass discrimination effects of the CI source. The absolute transmission of the instrument without the CI source was estimated with the HR-DMA method to plateau between the m/z range of 127 and 568 Th at around 1.5 %; however, for the CI source included, the depletion method showed a steady increase in relative transmission efficiency from the m/z range of the primary ion (mainly at 62 Th) to around 550 Th by a factor of around 5. The main advantages of the depletion method are that the instrument is used in the same operation mode as

  11. Secure Transmission with Artificial Noise over Fading Channels: Achievable Rate and Optimal Power Allocation

    Zhou, Xiangyun

    2010-01-01

    We consider the problem of secure communication with multi-antenna transmission in fading channels. The transmitter simultaneously transmits an information bearing signal to the intended receiver and artificial noise to the eavesdroppers. We obtain an analytical closed-form expression of an achievable secrecy rate, and use it as the objective function to optimize the transmit power allocation between the information signal and the artificial noise. Our analytical and numerical results show that equal power allocation is a simple yet near optimal strategy for the case of non-colluding eavesdroppers. When the number of colluding eavesdroppers increases, more power should be used to generate the artificial noise. We also provide an upper bound on the signal-to-noise ratio (SNR) above which the achievable secrecy rate is positive and show that the bound is tight at low SNR. Furthermore, we consider the impact of imperfect channel state information (CSI) at both the transmitter and the receiver and find that it is...

  12. Highly Efficient Fiber Lasers for Wireless Power Transmission Project

    National Aeronautics and Space Administration — We propose to develop ytterbium (Yb) fiber lasers with an electrical-to-optical efficiency of nominally 64% by directly coupling 80%-efficient diode lasers with Yb...

  13. Achieving energy efficiency in restructured markets, implications for IRP

    The shift of the focus of the vertically integrated model to the new unbundled models of organization to attain a ''new competitive'' Electricity Supply Industry brings new subjects into IRP (Integrated Resource Planning) study. The decision centralization on new capacity additions is being substituted by market mechanisms, changing the implementation of the IRP regarding both the construction of new capacity and the DSM. The implication for DSM is that, without a central planning process, it will not be possible to carry out IRP. In some countries they are implementing policies tending to create a more favourable attitude towards energy efficiency, in products and services. The conventional programmes of Demand-Side Management are being redesigned as added-value services to conserve or create market quota through Market Transformation mechanisms, such as Technology Procurement. (author)

  14. Achieving Textbook Multigrid Efficiency for Hydrostatic Ice Sheet Flow

    Brown, Jed

    2013-03-12

    The hydrostatic equations for ice sheet flow offer improved fidelity compared with the shallow ice approximation and shallow stream approximation popular in today\\'s ice sheet models. Nevertheless, they present a serious bottleneck because they require the solution of a three-dimensional (3D) nonlinear system, as opposed to the two-dimensional system present in the shallow stream approximation. This 3D system is posed on high-aspect domains with strong anisotropy and variation in coefficients, making it expensive to solve with current methods. This paper presents a Newton--Krylov multigrid solver for the hydrostatic equations that demonstrates textbook multigrid efficiency (an order of magnitude reduction in residual per iteration and solution of the fine-level system at a small multiple of the cost of a residual evaluation). Scalability on Blue Gene/P is demonstrated, and the method is compared to various algebraic methods that are in use or have been proposed as viable approaches.

  15. An ME-PC Enhanced HDMR Method for Efficient Statistical Analysis of Multiconductor Transmission Line Networks

    Yucel, Abdulkadir C.

    2015-05-05

    An efficient method for statistically characterizing multiconductor transmission line (MTL) networks subject to a large number of manufacturing uncertainties is presented. The proposed method achieves its efficiency by leveraging a high-dimensional model representation (HDMR) technique that approximates observables (quantities of interest in MTL networks, such as voltages/currents on mission-critical circuits) in terms of iteratively constructed component functions of only the most significant random variables (parameters that characterize the uncertainties in MTL networks, such as conductor locations and widths, and lumped element values). The efficiency of the proposed scheme is further increased using a multielement probabilistic collocation (ME-PC) method to compute the component functions of the HDMR. The ME-PC method makes use of generalized polynomial chaos (gPC) expansions to approximate the component functions, where the expansion coefficients are expressed in terms of integrals of the observable over the random domain. These integrals are numerically evaluated and the observable values at the quadrature/collocation points are computed using a fast deterministic simulator. The proposed method is capable of producing accurate statistical information pertinent to an observable that is rapidly varying across a high-dimensional random domain at a computational cost that is significantly lower than that of gPC or Monte Carlo methods. The applicability, efficiency, and accuracy of the method are demonstrated via statistical characterization of frequency-domain voltages in parallel wire, interconnect, and antenna corporate feed networks.

  16. Energy-Efficient Network Transmission between Satellite Swarms and Earth Stations Based on Lyapunov Optimization Techniques

    Weiwei Fang

    2014-01-01

    Full Text Available The recent advent of satellite swarm technologies has enabled space exploration with a massive number of picoclass, low-power, and low-weight spacecraft. However, developing swarm-based satellite systems, from conceptualization to validation, is a complex multidisciplinary activity. One of the primary challenges is how to achieve energy-efficient data transmission between the satellite swarm and terrestrial terminal stations. Employing Lyapunov optimization techniques, we present an online control algorithm to optimally dispatch traffic load among different satellite-ground links for minimizing overall energy consumption over time. Our algorithm is able to independently and simultaneously make control decisions on traffic dispatching over intersatellite-links and up-down-links so as to offer provable energy and delay guarantees, without requiring any statistical information of traffic arrivals and link condition. Rigorous analysis and extensive simulations have demonstrated the performance and robustness of the proposed new algorithm.

  17. An integrated framework for transmission cost allocation retaining efficiency concepts

    Lima, J.W. Marangon [Escola Federal de Engenharia de Itajuba, MG (Brazil); Gorenstin, B.G.; Vieira Filho, X. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil); Chipp, H.J.; Alvarenga Filho, S. [ELETROBRAS, Rio de Janeiro, RJ (Brazil); Hirota, M. [Companhia Energetica de Sao Paulo (CESP), SP (Brazil); Pereira, M.V.F. [Power System Research, Inc., Rio de Janeiro, RJ (Brazil)

    1994-12-31

    This paper describes a methodology for allocating transmission costs among utilities and wheeling agents. The proposed approach is based on the extension of marginal cost theory to take into account discrete component sizes and economy of scale, while retaining desirable economic properties such as revenue reconciliation and incentives for all participants to remain in the pool. The methodology is illustrated in case studies with the Brazilian system. (author) 21 refs., 1 fig., 3 tabs.

  18. Theoretical models of diffraction efficiencies of arc profiled bar transmission grating

    Shang, Wanli; Mei, Lusheng; Yang, Jiamin

    2012-06-01

    Diffraction efficiencies of transmission grating play important roles in accurate measurement of soft X-ray and grating applications. Circular, horizontal elliptical, and vertical elliptical arc profiled bar models were established from Kirchhoff diffraction theory with the Fraunhofer diffraction approximation to calculate the diffraction efficiencies of arc profiled bar transmission grating. The calculated results were compared with the available data from X-ray Optics web site of Lawrence Berkeley Laboratory's Center. Excellent agreements have been obtained. With these modes the diffraction efficiencies of the particular type of transmission grating having arc profiled bars can be simulated accurately and the best fit bar profiles can be obtained.

  19. Efficient Load Forecasting Optimized by Fuzzy Programming and OFDM Transmission

    Sandeep Sachdeva

    2011-01-01

    reduce the error of load forecasting, fuzzy method has been used with Artificial Neural Network (ANN and OFDM transmission is used to get data from outer world and send outputs to outer world accurately and quickly. The error has been reduced to a considerable level in the range of 2-3%. For further reducing the error, Orthogonal Frequency Division Multiplexing (OFDM can be used with Reed-Solomon (RS encoding. Further studies are going on with Fuzzy Regression methods to reduce the error more.

  20. One bit/s/Hz Spectrally Efficient Transmission for an Eight-Channel NRZ-Modulated DWDM System

    Vij, Robin; Sharma, Neeraj

    2016-03-01

    The core of the global telecommunication network consists of wavelength-division multiplexed (WDM) optical transmission systems. WDM is the technology of choice as it allows for a high spectral efficiency. We propose an effective way to counter the nonlinearities like four-wave mixing and cross-phase modulation to achieve the spectral efficiency of 1 bit/s/Hz using non-return-to-zero (NRZ) modulation format. We use the concept of non-uniform channel spacing and non-uniform power assignment between adjacent channels of the WDM system. We have simulated an eight-channel WDM lightwave system with bit rates of 10 and 25 Gbit/s.

  1. 10 CFR 435.7 - Water used to achieve energy efficiency. [Reserved

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Water used to achieve energy efficiency. 435.7 Section 435.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL LOW-RISE RESIDENTIAL BUILDINGS Mandatory Energy Efficiency Standards for Federal Low-Rise...

  2. Prenatal Transmission of Syphilis and Human Immunodeficiency Virus in Brazil: Achieving Regional Targets for Elimination.

    Cerda, Rodrigo; Perez, Freddy; Domingues, Rosa Maria S M; Luz, Paula M; Grinsztejn, Beatriz; Veloso, Valdilea G; Caffe, Sonja; Francke, Jordan A; Freedberg, Kenneth A; Ciaranello, Andrea L

    2015-04-01

    Background.  The Pan-American Health Organization has called for reducing (1) human immunodeficiency virus (HIV) mother-to-child transmission (MTCT) to ≤0.30 infections/1000 live births (LB), (2) HIV MTCT risk to ≤2.0%, and (3) congenital syphilis (CS) incidence to ≤0.50/1000 LB in the Americas by 2015. Methods.  Using published Brazilian data in a mathematical model, we simulated a cohort of pregnant women from antenatal care (ANC) through birth. We investigated 2 scenarios: "current access" (89.1% receive one ANC syphilis test and 41.1% receive 2; 81.7% receive one ANC HIV test and 18.9% receive birth testing; if diagnosed, 81.0% are treated for syphilis and 87.5% are treated for HIV) and "ideal access" (95% of women undergo 2 HIV and syphilis screenings; 95% receive appropriate treatment). We conducted univariate and multivariate sensitivity analyses on key inputs. Results.  With current access, we projected 2.95 CS cases/1000 LB, 0.29 HIV infections/1000 LB, 7.1% HIV MTCT risk, and 11.11 intrauterine fetal demises (IUFD)/1000 pregnancies, with significant regional variation. With ideal access, we projected improved outcomes: 1.00 CS cases/1000 LB, 0.10 HIV infections/1000 LB, HIV MTCT risk of 2.4%, and 10.65 IUFD/1000 pregnancies. Increased testing drove the greatest improvements. Even with ideal access, only HIV infections/1000 LB met elimination goals. Achieving all targets required testing and treatment >95% and reductions in prevalence and incidence of HIV and syphilis. Conclusions.  Increasing access to care and HIV and syphilis antenatal testing will substantially reduce HIV and syphilis MTCT in Brazil. In addition, regionally tailored interventions reducing syphilis incidence and prevalence and supporting HIV treatment adherence are necessary to completely meet elimination goals. PMID:26180825

  3. Efficient Load Forecasting Optimized by Fuzzy Programming and OFDM Transmission

    U. P. Singh; Ajat Shatru Arora; Maninder Singh; Sandeep Sachdeva

    2011-01-01

    Today, it is very important for developed and developing countries to consume electricity more efficiently. Though developed countries do not want to waste electricity and developing countries cannot waste electricity. This leads to the concept: load forecasting. This paper is written for the short-term load forecasting on daily basis, hourly, or half-hourly basis or real time load forecasting. But as we move from daily to hourly basis of load forecasting, the error of load forecasting increa...

  4. Dielectric Huygens’ Metasurface for High-Efficiency Hologram Operating in Transmission Mode

    Zhao, Wenyu; Jiang, Huan; Liu, Bingyi; Song, Jie; Jiang, Yongyuan; Tang, Chengchun; Li, Junjie

    2016-01-01

    Conventional metasurface holograms relying on metal antennas for phase manipulation suffer from strong Ohmic loss and incomplete polarization conversion. The efficiency is limited to rather small values when operating in transmission mode. Here, we implement a high-efficiency transmissive metasurface hologram by leveraging the recently developed Huygens’ metasurface to construct an electric and magnetic sheet with a transmission efficiency up to 86% and optical efficiency of 23.6%. The high-efficiency originates from the simultaneous excitations of the Mie-type electric and magnetic dipole resonances in the meta-atoms composed of silicon nanodisks. Our hologram shows high fidelity over a wide spectral range and promises to be an outstanding alternative for display applications. PMID:27457708

  5. Dielectric Huygens' Metasurface for High-Efficiency Hologram Operating in Transmission Mode.

    Zhao, Wenyu; Jiang, Huan; Liu, Bingyi; Song, Jie; Jiang, Yongyuan; Tang, Chengchun; Li, Junjie

    2016-01-01

    Conventional metasurface holograms relying on metal antennas for phase manipulation suffer from strong Ohmic loss and incomplete polarization conversion. The efficiency is limited to rather small values when operating in transmission mode. Here, we implement a high-efficiency transmissive metasurface hologram by leveraging the recently developed Huygens' metasurface to construct an electric and magnetic sheet with a transmission efficiency up to 86% and optical efficiency of 23.6%. The high-efficiency originates from the simultaneous excitations of the Mie-type electric and magnetic dipole resonances in the meta-atoms composed of silicon nanodisks. Our hologram shows high fidelity over a wide spectral range and promises to be an outstanding alternative for display applications. PMID:27457708

  6. Dielectric Huygens’ Metasurface for High-Efficiency Hologram Operating in Transmission Mode

    Zhao, Wenyu; Jiang, Huan; Liu, Bingyi; Song, Jie; Jiang, Yongyuan; Tang, Chengchun; Li, Junjie

    2016-07-01

    Conventional metasurface holograms relying on metal antennas for phase manipulation suffer from strong Ohmic loss and incomplete polarization conversion. The efficiency is limited to rather small values when operating in transmission mode. Here, we implement a high-efficiency transmissive metasurface hologram by leveraging the recently developed Huygens’ metasurface to construct an electric and magnetic sheet with a transmission efficiency up to 86% and optical efficiency of 23.6%. The high-efficiency originates from the simultaneous excitations of the Mie-type electric and magnetic dipole resonances in the meta-atoms composed of silicon nanodisks. Our hologram shows high fidelity over a wide spectral range and promises to be an outstanding alternative for display applications.

  7. Designing an efficient LT-code with unequal error protection for image transmission

    S. Marques, F.; Schwartz, C.; Pinho, M. S.; Finamore, W. A.

    2015-10-01

    The use of images from earth observation satellites is spread over different applications, such as a car navigation systems and a disaster monitoring. In general, those images are captured by on board imaging devices and must be transmitted to the Earth using a communication system. Even though a high resolution image can produce a better Quality of Service, it leads to transmitters with high bit rate which require a large bandwidth and expend a large amount of energy. Therefore, it is very important to design efficient communication systems. From communication theory, it is well known that a source encoder is crucial in an efficient system. In a remote sensing satellite image transmission, this efficiency is achieved by using an image compressor, to reduce the amount of data which must be transmitted. The Consultative Committee for Space Data Systems (CCSDS), a multinational forum for the development of communications and data system standards for space flight, establishes a recommended standard for a data compression algorithm for images from space systems. Unfortunately, in the satellite communication channel, the transmitted signal is corrupted by the presence of noise, interference signals, etc. Therefore, the receiver of a digital communication system may fail to recover the transmitted bit. Actually, a channel code can be used to reduce the effect of this failure. In 2002, the Luby Transform code (LT-code) was introduced and it was shown that it was very efficient when the binary erasure channel model was used. Since the effect of the bit recovery failure depends on the position of the bit in the compressed image stream, in the last decade many e orts have been made to develop LT-code with unequal error protection. In 2012, Arslan et al. showed improvements when LT-codes with unequal error protection were used in images compressed by SPIHT algorithm. The techniques presented by Arslan et al. can be adapted to work with the algorithm for image compression

  8. Behaviours, transmissions, generations: why is energy efficiency not enough?

    Garabuau-Moussaoui, Isabelle (Electricite de France, Research and Development (France))

    2009-07-01

    Energy use is nowadays a very important question, in the context of global warming and expensive prices of energy. 'Energy conservation' is a paradox: environmental awareness increases, but also energy demand. Sociological knowledge concerning energy uses and energy savings remains important to understand the possible evolutions of practices and values and thus the possible future energy policies. Can the 'consumer society' become a 'less energy-intensive' society? This paper proposes to innovate with a 'new' way to analyse behaviours and to help policy makers to break the walls of 'the behavioural complexity'. We argue that energy efficiency, energy-using products and activities are socially embedded. More specifically, they depend on the 'social age' of people (children, teenagers, young adults, parents, old age people) and on their generation (events, experiences that people did live). The demonstration is based on the analysis of several qualitative studies carried out in France, showing that the generational and social ages analysis could be very efficient and innovative to understand: How are information, policies and energy-efficient technologies understood and embodied by people according to their age and their 'life story'? What kind of 'energy-related material culture' have people, and how does it evolve during the life? In a context of increasing energy demand, is it possible to change the energy-intensive 'socio-technical' mainstream towards a more sustainable way of life? What are the best moments during life for a behavioural change towards a less energy intensive way of life? Can we count on the new generation, to be more aware and less 'energy-intensive'?

  9. Efficient, balanced, transmission line RF circuits by back propagation of common impedance nodes

    Markhasin, Evgeny; Hu, Jianping; Su, Yongchao; Herzfeld, Judith; Griffin, Robert G.

    2013-06-01

    We present a new, efficient strategy for designing fully balanced transmission line RF circuits for solid state NMR probes based on back propagation of common impedance nodes (BPCIN). In this approach, the impedance node phenomenon is the sole means of achieving mutual RF isolation and balance in all RF channels. BPCIN is illustrated using a custom double resonance 3.2 mm MAS probe operating at 500 MHz (1H) and 125 MHz (13C). When fully optimized, the probe is capable of producing high homogeneity (810°/90° ratios of 86% and 89% for 1H and 13C, respectively) and high efficiency (γB1 = 100 kHz for 1H and 13C at 70 W and 180 W of RF input, respectively; up to 360 kHz for 1H). The probe's performance is illustrated by 2D MAS correlation spectra of microcrystals of the tripeptide N-f-MLF-OH and hydrated amyloid fibrils of the protein PI3-SH3.

  10. Efficient data transmission from silicon wafer strip detectors

    An architecture for on-wafer processing is proposed for central silicon-strip tracker systems as they are currently designed for high energy physics experiments at the SSC, and for heavy ion experiments at RHIC. The data compression achievable with on-wafer processing would make it possible to transmit all data generated to the outside of the detector system. A set of data which completely describes the state of the wafer for low occupancy events and which contains important statistical information for more complex events can be transmitted immediately. This information could be used in early trigger decisions. Additional data packages which complete the description of the state of the wafer vary in size and are sent through a second channel. By buffering this channel the required bandwidth can be kept far below the peak data rates which occur in rate but interesting events. 18 refs

  11. Efficient Sequence Detection of Multicarrier Transmissions over Doubly Dispersive Channels

    Hwang Sung-Jun

    2006-01-01

    Full Text Available We propose a high-spectral-efficiency multicarrier system for communication over the doubly dispersive (DD channel which yields very low frame error rate (FER, with quadratic (in the frame length receiver complexity. To accomplish this, we combine a non-(biorthogonal multicarrier modulation (MCM scheme recently proposed by the authors with novel sequence detection (SD and channel estimation (CE algorithms. In particular, our MCM scheme allows us to accurately represent the DD channels otherwise complicated intercarrier interference (ICI and intersymbol interference (ISI response with a relatively small number of coefficients. The SD and CE algorithms then leverage this sparse ICI/ISI structure for low-complexity operation. Our SD algorithm combines a novel adaptive breadth-first search procedure with a new fast MMSE-GDFE preprocessor, while our CE algorithm uses a rank-reduced pilot-aided Wiener technique to estimate only the significant ICI/ISI coefficients.

  12. Energy-efficient algorithm for sensor networks with non-uniform maximum transmission range.

    Yu, Yimin; Song, Chao; Liu, Ming; Gong, Haigang

    2011-01-01

    In wireless sensor networks (WSNs), the energy hole problem is a key factor affecting the network lifetime. In a circular multi-hop sensor network (modeled as concentric coronas), the optimal transmission ranges of all coronas can effectively improve network lifetime. In this paper, we investigate WSNs with non-uniform maximum transmission ranges, where sensor nodes deployed in different regions may differ in their maximum transmission range. Then, we propose an Energy-efficient algorithm for Non-uniform Maximum Transmission range (ENMT), which can search approximate optimal transmission ranges of all coronas in order to prolong network lifetime. Furthermore, the simulation results indicate that ENMT performs better than other algorithms. PMID:22163950

  13. Energy-Efficient Algorithm for Sensor Networks with Non-Uniform Maximum Transmission Range

    Yimin Yu

    2011-06-01

    Full Text Available In wireless sensor networks (WSNs, the energy hole problem is a key factor affecting the network lifetime. In a circular multi-hop sensor network (modeled as concentric coronas, the optimal transmission ranges of all coronas can effectively improve network lifetime. In this paper, we investigate WSNs with non-uniform maximum transmission ranges, where sensor nodes deployed in different regions may differ in their maximum transmission range. Then, we propose an Energy-efficient algorithm for Non-uniform Maximum Transmission range (ENMT, which can search approximate optimal transmission ranges of all coronas in order to prolong network lifetime. Furthermore, the simulation results indicate that ENMT performs better than other algorithms.

  14. An Energy-efficient Data Transmission Scheme in Underwater Wireless Sensor Networks

    Y. Emami; R. Javidan

    2016-01-01

    Energy is a precious resource in underwater wireless sensor networks (UWSNs). In these networks, the number of data transmissions between sensor nodes dominates energy consumption. Complex signal processing techniques also increase energy consumption. In this paper an energy-efficient data transmission scheme based on bloom filters is proposed. Extensive simulation is carried out to demonstrate the effectiveness of the proposed method. Simulation results indicate that the proposed scheme outp...

  15. Efficient Sparse Signal Transmission over a Lossy Link Using Compressive Sensing

    Liantao Wu; Kai Yu; Dongyu Cao; Yuhen Hu; Zhi Wang

    2015-01-01

    Reliable data transmission over lossy communication link is expensive due to overheads for error protection. For signals that have inherent sparse structures, compressive sensing (CS) is applied to facilitate efficient sparse signal transmissions over lossy communication links without data compression or error protection. The natural packet loss in the lossy link is modeled as a random sampling process of the transmitted data, and the original signal will be reconstructed from the lossy trans...

  16. STUDY ON SHIFT SCHEDULE OF AUTOMATIC TRANSMISSION TO IMPROVE ENGINEERING VEHICULAR EFFICIENCY

    Gong Jie; Zhao Dingxuan; Huang Haidong; Gong Wenbin; Chen Ying

    2004-01-01

    New shift schedule for automatic transmission is proposed from the point of view of saving energy.The bench-test of automatic shift adopting this shift schedule is done on automatic transmission's test-bed.The experimental results show the shift schedule is correct.This shift schedule has enriched the theory of vehicle automatic maneuvering and will improve the efficiency of hydrodynamic drive system of the vehicle.

  17. Innovative strategies devised by Indian microfinance institutions to achieve cost efficiency

    Nadiya Marakkath

    2012-12-01

    Full Text Available This study is a discussion on the ‘Non-Governmental Organization-Microfinance Institution Partnership Model’ and ‘Securitization Model’ used by Indian microfinance institutions to achieve cost efficiency. These two models are effective strategies devised and used by efficient and sustainable Indian MFIs to reduce their operating cost and financing cost. Achieving such cost efficiency is crucial for microfinance institutions to attain operational self-sustainability without levying high interest rates. Using interview method the study elicits information on these innovative strategies and recommends them to be worthy of emulation for other microfinance institutions operating in the Indian microfinance industry.

  18. Energy-efficient network reprogramming scheme with Raptor code by using transmission power control in WSNs

    Dongwan Kim

    2014-04-01

    Full Text Available In wireless sensor networks, the necessity of reprogramming becomes more and more important for variety of purposes. However, the reprogramming produces a large amount of data and causes large energy consumption and interference. In this Letter, we propose an energy-efficient reprogramming scheme with Raptor code by using transmission power control. By selecting proper relay nodes, relay nodes’ transmission power and Raptor code overhead, the proposed scheme minimises energy consumption while guaranteeing reliable transmission. This is verified by comparing it with conventional schemes.

  19. Adaptive efficient video transmission over the Internet based on congestion control and RS coding

    黄伟红; 张福炎; 孙正兴

    2002-01-01

    An approach based on adaptive congestion control and adaptive error recovery with RS (Reed-Solomon) coding method is presented for efficient video transmission over the Internet.Featured by weighted moving average rate control and TCP-fdendliness,AVSP,a novel adaptive video streaming protocol,is designed with adjustable rate control parameters so as to respond quickly to the QoS status fluctuation during video transmission over the Internet.Combined with congestion control policy,an adaptive RS coding error recovery scheme with variable parameters is presented to enhance the robustness of MPEG video transmission over the Intemet with restriction to the total system bandwidth.``

  20. Transmission prices in the electric system. Technical constraints and economic efficiency

    This article analyses the two main models at the core of today's theoretical discussion on transmission pricing in electricity sectors under competition. The first aim of the paper is showing how technical constraints that characterise transmission systems may affect energy production and transmission and therefore the definition of the price system for using the electric grid. The second aim of the paper is showing how it is possible to suggest solutions, although not free from limitations, that can be used for an efficient management of electric systems characterised by generation and consumption sectors under competition

  1. Efficient Sparse Signal Transmission over a Lossy Link Using Compressive Sensing

    Liantao Wu

    2015-08-01

    Full Text Available Reliable data transmission over lossy communication link is expensive due to overheads for error protection. For signals that have inherent sparse structures, compressive sensing (CS is applied to facilitate efficient sparse signal transmissions over lossy communication links without data compression or error protection. The natural packet loss in the lossy link is modeled as a random sampling process of the transmitted data, and the original signal will be reconstructed from the lossy transmission results using the CS-based reconstruction method at the receiving end. The impacts of packet lengths on transmission efficiency under different channel conditions have been discussed, and interleaving is incorporated to mitigate the impact of burst data loss. Extensive simulations and experiments have been conducted and compared to the traditional automatic repeat request (ARQ interpolation technique, and very favorable results have been observed in terms of both accuracy of the reconstructed signals and the transmission energy consumption. Furthermore, the packet length effect provides useful insights for using compressed sensing for efficient sparse signal transmission via lossy links.

  2. Transmission cost allocation for an efficient tariff action of electricity in a liberalised market

    The work is focused on the evaluation of the costs of an electricity transmission system operator and on their allocation among the users of the grid in liberalized market. After a recall of the goals of an efficient tariff for transmission, an original method for the cost allocation is proposed called ZI. Based on the marginal cost approach, this method could be the base for setting an efficient transmission tariff that at the same time covers costs and stimulates efficient behaviours. The performances of such an approach have been tested on a real 47 bus grid and ZI tariffs have been compared to the traditional postage stamp ones, highlighting the strong differences between them

  3. Factors influencing efficiency of laser wireless power transmission system for micro unmanned aerial vehicles

    Liu, Xiaoguang; Hua, Wenshen; Liu, Xun

    2014-12-01

    Micro unmanned aerial vehicle, mostly powered by electricity, plays an important role in many military and civil applications, e.g. military detection, communication relay et al. But restricted endurance ability severely limits its applications. To solve the problem, laser wireless power transmission system is proposed. However, overall efficiency of the system is quite low. This paper describes basic structure of laser wireless power transmission system and its working process. The system consists of two major modules: a high power laser source transmitting energy and a photovoltaic receiver converting optical energy into electricity. Then factors influencing efficiency of the system are analyzed. It suggests that electro-optical efficiency of laser, atmospheric impact on laser beam and photo-electric efficiency of photovoltaic receiver play significant role in overall efficiency of the system. Atmospheric impact on laser beam mostly derived from refraction, absorption, scattering and turbulence effects, leads to drop in energy and quality of laser beam. Efficiency of photovoltaic receiver is affected by photovoltaic materials. In addition, matching degree between intensity distribution of laser beam and layout of photovoltaic receiver also obviously influence efficiency of photovoltaic receiver. Experiment results suggest that under non-uniform laser beam illumination, efficiency of photovoltaic receiver mostly depends on layout of photovoltaic receiver. Through optimizing the layout of photovoltaic receiver based on intensity distribution of laser beam, output power is significantly improved. The analysis may help to take corresponding measures to alleviate negative effects of these factors and improve performance of laser wireless power transmission system.

  4. Highly efficient solutions for smart and bulk power transmission of 'green energy'

    Breuer, Wilfried; Retzmann, Dietmar; Uecker, Karl

    2010-09-15

    Environmental constraints, loss minimization and CO2 reduction will play an increasingly more important role in future. Security and sustainability of power supply as well as economic efficiency needs application of advanced technologies. Innovative solutions with HVDC (High Voltage Direct Current) and FACTS (Flexible AC Transmission Systems) have the potential to cope with these challenges. They provide the features which are necessary to avoid technical problems in power systems, they increase the transmission capacity and system stability very efficiently and help prevent cascading outages. Furthermore, they are essential for Grid Access of Renewable Energy Sources such as Hydro, Wind and Solar-Energy.

  5. Study of transmission grating diffraction efficiencies for soft X—ray

    YANGJiamin; CUIMingqi; 等

    1999-01-01

    Tansmission grating spectrometers are extensively used to measure absolute X-ray spectra in a photon-energy range below 1000eV.the transmission grating,as its dispersive element,must be calibrated to obtain its diffraction efficiencies.Calibrations of absolute diffraction efficiencies of the transmission grating at photon energy of 844eV have been caried out on Bejing synchrotron Radiation Facility.With the aid of grating model,all of the grating structure parameters have been determined and the absolute diffraction efficeencies in a photon-energy range below 2000eV have also been calculated and discussed.

  6. Joint Support and Efficient Offshore Investment: Market and Transmission Connection Barriers and Solutions

    Schröder, Sascha Thorsten; Kitzing, Lena; Klinge Jacobsen, Henrik;

    2012-01-01

    Different support schemes are applied for the promotion of renewable energy sources in EU Member States. Current EU legislation opens opportunities for international cooperation to achieve national renewable targets more efficiently, either by statistical transfers, joint projects or joint support...

  7. Comparison of the Efficiency of Biological Transmission of Anaplasma marginale (Rickettsiales: Anaplasmataceae) by Dermacentor andersoni Stiles (Acari: Ixodidae) with Mechanical Transmission by the Horse Fly, Tabanus fuscicos

    Mechanical transmission of Anaplasma marginale by horse flies (Tabanidae) is thought to be epidemiologically significant in some areas of the US. We compared the relative efficiencies of mechanical transmission of Anaplasma marginale by the horse fly, Tabanus fuscicostatus Hine during acute infectio...

  8. Study of transmission grating diffraction efficiencies for soft X-ray

    1999-01-01

    Tansmission grating spectrometers are extensively used tomeasure absolute X-ray spectra in a photon-energy rangebelow 1000 eV. The transmission grating, as its dispersive element, must be calibrated to obtain its diffraction efficiencies.Calibrations of absolute diffraction efficiencies of the transmissiongrating at photon energy of 844 eV have been carried out onBeijing Synchrotron Radiation Facility. With the aid of gratingmodel, all of the grating structure parameters have been determinedand the absolute diffraction efficiencies in a photon-energy rangebelow 2000 eV have also been calculated and discussed.

  9. AN ENERGY MODEL FOR ACHIEVING HIGH PERFORMANCE BURST TRANSMISSION IN OBCS NETWORKS

    Renuka, R.; Kavitha, V.

    2013-01-01

    Optical burst switching is a promising solution for all optical WDM networks. It combines the benefits of optical circuit switching and optical packet switching. In OBS, the user data is collected at the edge of the network, sorted based on the destination address and grouped into variable size bursts. The OBS framework has been widely used in past years, for recent work use Optical Burst Chain switching (OBCS) to achieve high performance. Here switching unit is burst chain it consist of non-...

  10. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels

    Singh, Meenesh R.; Clark, Ezra L.; Bell, Alexis T.

    2015-11-01

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32-42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0-0.9 V, 0.9-1.95 V, and 1.95-3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. We show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices.

  11. Dynamic Analysis and Control of an Automatic Transmission for Start-Stop Function and Efficiency Improvement

    Yang Liu; Shuhan Wang; Peng Dong; Xiangyang Xu

    2015-01-01

    An electric oil pump (EOP) was integrated into the hydraulic system and an automatic transmission (AT) mechanical oil pump (MOP) was downsized. These processes were performed to combine a start-stop function with the AT and further improve the transmission efficiency. Furthermore, this study established a dynamics model of power loss and leakage of an 8-speed AT; a flow-based control algorithm of the EOP was then developed to realize the start-stop function and support the MOP to meet the flo...

  12. Irregular and regular LDPC codes with high spectrum efficiency modulation in image transmission over fading channel

    Ma Piming; Yuan Dongfeng

    2005-01-01

    If the degree distribution is chosen carefully, the irregular low-density parity-check (LDPC) codes can outperform the regular ones. An image transmission system is proposed by combining regular and irregular LDPC codes with 16QAM/64QAM modulation to improve both efficiency and reliability. Simulaton results show that LDPC codes are good coding schemes over fading channel in image communication with lower system complexity. More over, irregular codes can obtain a code gain of about 0.7 dB compared with regular ones when BER is 10-4. So the irregular LDPC codes are more suitable for image transmission than the regular codes.

  13. Methodology to Achieve Enhanced Data Transmission Rate using Li-Fi in VLC Technology

    Md. Shahadat Hossain,,

    2014-12-01

    Full Text Available Li-Fi (Light Fidelity or optical Wi-Fi is the transmission of data using light waves by varying the light intensity faster than human eye can follow using Visible Light Communication (VLC technology in free space. This is just like as “Data Through Illumination”. VLC uses rapid pulses of light to transmit information wirelessly. VLC using LEDs is emerging as a key technology for a ubiquitous communication system, because LED has the advantages of fast switching, long life expectancy, being less expensive and being visible light that is safe for the human body. LEDs are different from the other kinds of lamps because they are semiconductors. This characteristic gives them the capability to switch-on and off within few nanoseconds or billionth of a second. Converted in terms of data rates, this corresponds to 1 Gbits/s or more. In order to compare, at best Wi-Fi can reach 100 Mbits/s data rates and so at least 10 times or more lower. Here we shows some new conceptual methods by which we can transmit data in parallel using VLC technology. If this application is put into use, we can use every bulb like a Wi-Fi hot spot to transmit the data with ultra-high speed such as more than 10 Gbits/s.

  14. AN ENERGY MODEL FOR ACHIEVING HIGH PERFORMANCE BURST TRANSMISSION IN OBCS NETWORKS

    R.RENUKA

    2013-04-01

    Full Text Available Optical burst switching is a promising solution for all optical WDM networks. It combines the benefits of optical circuit switching and optical packet switching. In OBS, the user data is collected at the edge of the network, sorted based on the destination address and grouped into variable size bursts. The OBS framework has been widely used in past years, for recent work use Optical Burst Chain switching (OBCS to achieve high performance. Here switching unit is burst chain it consist of non-periodic bursts in one wavelength. We present extensive simulation result for throughput, delay and energy to demonstrate its superior performance over OBS networks.

  15. Fabrication of Efficient, Large Aperture Transmission Diffraction Gratings by Ion-Beam Etching

    The utilization of high-power short pulse laser employing chirped-pulse amplification (CPA) for material processing and inertial confinement research is widely increasing. The performance of these high-power CPA laser system continues to be limited by the ability of the pulse compression gratings to hold up to the high-average-power or high-peak-power of the laser. Pulse compression gratings used in transmission and fabricated out of bulk fused silica have intrinsically the highest laser damage threshold when compared with metal or multilayer dielectric gratings that work in reflection. LLNL has developed processing capability to produce high efficiency fused silica transmission gratings at sizes useful to future Petawatt-class systems, and has demonstrated high efficiency at smaller aperture. This report shows that fused silica diffraction exhibiting >95% efficiency into the -1 diffraction order in transmission (90o deflection of the incident light, at an incidence angle of 45o to the grating face). The microstructure of this grating consisted of grooves ion-beam etched to a depth of 1.6 microns with a pitch of 0.75 microns, using a holographically produced photoresist mask that was subsequently stripped away in significance to the fabrication of the small scale high efficiency grating was the development of the processing technology and infrastructure for production of such gratings at up to 65 cm diameter. LLNL is the currently the only location in the world with the ability to coat, interferometrically expose, and ion etch diffractive optics at this aperture. Below, we describe the design, fabrication, performance and, the scaleup process for a producing a high-efficiency transmission grating on a 65 cm fused silica substrate

  16. Energy transmission and power sources for mechanical circulatory support devices to achieve total implantability.

    Wang, Jake X; Smith, Joshua R; Bonde, Pramod

    2014-04-01

    Left ventricular assist device therapy has radically improved congestive heart failure survival with smaller rotary pumps. The driveline used to power today's left ventricular assist devices, however, continues to be a source of infection, traumatic damage, and rehospitalization. Previous attempts to wirelessly power left ventricular assist devices using transcutaneous energy transfer systems have been limited by restrictions on separation distance and alignment between the transmit and receive coils. Resonant electrical energy transfer allows power delivery at larger distances without compromising safety and efficiency. This review covers the efforts to wirelessly power mechanical circulatory assist devices and the progress made in enhancing their energy sources. PMID:24530103

  17. Code Division Multiplexing Using AI Based Custom Constellation Scheme - Efficient Modulation for High Data rate Transmission

    K.SESHADRI SASTRY,

    2010-06-01

    Full Text Available To achieve high bit rate in transmission over wireless channels frequency reuse is an encouraging concept . Rather than dividing allocated frequency spectrum into narrow band width channels , one for each user information is transmitted over a very wide frequency spectrum using the same carrier frequency within same frequency band . In this paper we propose code division multiplexing scheme in which Custom QAM modulator itself is used as code . The propose system is simulated and tested in Matlab 7.4.

  18. Code Division Multiplexing Using AI Based Custom Constellation Scheme - Efficient Modulation for High Data rate Transmission

    K.SESHADRI SASTRY,; Dr. M. S. Prasad Babu

    2010-01-01

    To achieve high bit rate in transmission over wireless channels frequency reuse is an encouraging concept . Rather than dividing allocated frequency spectrum into narrow band width channels , one for each user information is transmitted over a very wide frequency spectrum using the same carrier frequency within same frequency band . In this paper we propose code division multiplexing scheme in which Custom QAM modulator itself is used as code . The propose system is simulated and tested in Ma...

  19. In-line FINCH super resolution digital holographic fluorescence microscopy using a high efficiency transmission liquid crystal GRIN lens

    Brooker, Gary; Siegel, Nisan; Rosen, Joseph; HASHIMOTO, NOBUYUKI; Kurihara, Makoto; Tanabe, Ayano

    2013-01-01

    We report a new optical arrangement that creates high efficiency, high quality Fresnel Incoherent Correlation Holography (FINCH) holograms using polarization sensitive transmission liquid crystal gradient index (TLCGRIN) diffractive lenses. In contrast, current universal practice in the field employs reflective spatial light modulators (SLM) to separate sample and reference beams. Polarization sensitive TLCGRIN lenses enable a straight optical path, have >90% transmission efficiency, are not ...

  20. Partial transmission block production for real efficient method of block and MLC

    Choi, Ji Min; Park, Ju Young; Ju, Sang Kyu; Park, Jong Ho [Dept. of Radiation Oncology, Samsung Medical Center, Sunkyunkwan University, Seoul (Korea, Republic of)

    2004-09-15

    The Vaginal, the urethra, the vulva and anal cancer avoid the many dose to femur head and the additional treatment is necessary in inguinal LN. The partial transmission block to use inguinal LN addition there is to a method which it treats and produce partial transmission block a method and the MLC which to it analyzes. The Inguinal the LN treatment patient partial transmission it used block and the MLC in the object and with solid water phantom with the patient it reappeared the same depth. In order to analyze the error of the junction the EDR2 (Extended dose range, the Kodak and the U.S) it used the Film and it got film scanner it got the beam profile. The partial transmission block and the MLC bias characteristic, accuracy and stability of production for, it shared at hour and comparison it analyzed. The partial the transmission block compares in the MLC and the block production is difficult and production hour also above 1 hours. The custom the block the place where it revises the error of the junction is a difficult problem. If use of the MLC the fabrication will be break and only the periodical calibration of the MLC it will do and it will be able to use easily. The Inguinal there is to LN treatment and partial transmission block and the MLC there is efficiency of each one but there is a place where the junction of block for partial transmission block the production hour is caught long and it fixes and a point where the control of the block is difficult. Like this problem it transfers with the MLC and if it treats, it means the effective treatment will be possible.

  1. Partial transmission block production for real efficient method of block and MLC

    The Vaginal, the urethra, the vulva and anal cancer avoid the many dose to femur head and the additional treatment is necessary in inguinal LN. The partial transmission block to use inguinal LN addition there is to a method which it treats and produce partial transmission block a method and the MLC which to it analyzes. The Inguinal the LN treatment patient partial transmission it used block and the MLC in the object and with solid water phantom with the patient it reappeared the same depth. In order to analyze the error of the junction the EDR2 (Extended dose range, the Kodak and the U.S) it used the Film and it got film scanner it got the beam profile. The partial transmission block and the MLC bias characteristic, accuracy and stability of production for, it shared at hour and comparison it analyzed. The partial the transmission block compares in the MLC and the block production is difficult and production hour also above 1 hours. The custom the block the place where it revises the error of the junction is a difficult problem. If use of the MLC the fabrication will be break and only the periodical calibration of the MLC it will do and it will be able to use easily. The Inguinal there is to LN treatment and partial transmission block and the MLC there is efficiency of each one but there is a place where the junction of block for partial transmission block the production hour is caught long and it fixes and a point where the control of the block is difficult. Like this problem it transfers with the MLC and if it treats, it means the effective treatment will be possible.

  2. Efficient transmission of subthreshold signals in complex networks of spiking neurons

    Torres, Joaquin J; Marro, J

    2014-01-01

    We investigate the efficient transmission and processing of weak signals (subthreshold) in a realistic neural medium in the presence of different levels of the underlying noise. Assuming Hebbian weights for maximal synaptic conductances - that naturally balances the network with excitatory and inhibitory synapses - and considering short-term synaptic plasticity affecting such conductances, we found different dynamical phases in the system. This includes a memory phase where population of neurons remain synchronized, an oscillatory phase where transitions between different synchronized populations of neurons appears and an asynchronous or noisy phase. When a weak stimulus input is applied to each neuron and increasing the level of noise in the medium we found an efficient transmission of such stimuli around the transition and critical points separating different phases and therefore for quite well defined and different levels of stochasticity in the system. We proved that this intriguing phenomenon is quite ro...

  3. Efficiency and integration in the Zambian sugar market: analysing price transmission, price formation and policy

    Chisanga, Brian

    2012-01-01

    Efficiency and integration in the Zambian sugar market: analysing price transmission, price formation and policy By Brian Chisanga Degree: MSc. Agric (Agricultural Economics) Department: Agricultural Economics, Extension and Rural Development Supervisor: Dr Ferdinand Meyer Zambia ranks as one of the lowest cost producers of sugar. However, Zambia‟s domestic sugar price has been high and volatile and is substantially higher than the world price. This has raised concern among stakeholders and f...

  4. Opportunities for Efficiency Improvements in the U.S. Electricity Transmission and Distribution System

    Jackson, Roderick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Onar, Omer C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kirkham, Harold [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fisher, Emily [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Burkes, Klaehn [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Starke, Michael R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mohammed, Olama [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Weeks, George [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-04-01

    Since 2000, more than 172 quads of electricity have been transmitted on the US transmission and distribution (T&D) grid. Given this significant amount of energy flow, establishing and maintaining an efficient T&D grid is paramount. As shown in the figure below, the total percentage of overall losses in the US electric grid is approximately 6% (5.12% in 2012) (30% lower than the world average since 2000). While these efficiency losses appear to be relatively small from a percentage perspective, the total estimated electricity loss during this time is 10.8 quads.

  5. Self-learning Multiscale Simulation for Achieving High Accuracy and High Efficiency Simultaneously

    Li, Wenfei

    2009-01-01

    We propose a new multi-scale molecular dynamics simulation method which can achieve high accuracy and high sampling efficiency simultaneously without aforehand knowledge of the coarse grained (CG) potential and test it for a biomolecular system. Based on the resolution exchange simulations between atomistic and CG replicas, a self-learning strategy is introduced to progressively improve the CG potential by an iterative way. Two tests show that, the new method can rapidly improve the CG potential and achieve efficient sampling even starting from an unrealistic CG potential. The resulting free energy agreed well with exact result and the convergence by the method was much faster than that by the replica exchange method. The method is generic and can be applied to many biological as well as non-biological problems.

  6. Device engineering of perovskite solar cells to achieve near ideal efficiency

    Despite the exciting recent research on perovskite based solar cells, the design space for further optimization and the practical limits of efficiency are not well known in the community. In this letter, we address these aspects through theoretical calculations and detailed numerical simulations. Here, we first provide the detailed balance limit efficiency in the presence of radiative and Auger recombination. Then, using coupled optical and carrier transport simulations, we identify the physical mechanisms that contribute towards bias dependent carrier collection, and hence low fill factors of current perovskite based solar cells. Our detailed simulations indicate that it is indeed possible to achieve efficiencies and fill factors greater than 25% and 85%, respectively, with near ideal super-position characteristics even in the presence of Auger recombination

  7. Achievable Efficiency of Numerical Methods for Simulations of Solar Surface Convection

    Grimm-Strele, Hannes; Muthsam, Herbert J

    2014-01-01

    We investigate the achievable efficiency of both the time and the space discretisation methods used in Antares. We show that the fifth order variant of WENO combined with a second order Runge-Kutta scheme is not only more accurate than standard first and second order schemes, but also more efficient taking the computation time into account. Then, we calculate the error decay rates of WENO with several explicit Runge-Kutta schemes for advective and diffusive problems with smooth and non-smooth initial conditions. With this data, we estimate the computational costs of three-dimensional simulations and show that SSP RK(3,2) is the most efficient scheme considered in this comparison.

  8. Device engineering of perovskite solar cells to achieve near ideal efficiency

    Agarwal, Sumanshu, E-mail: sumanshu@iitb.ac.in, E-mail: prnair@ee.iitb.ac.in [Department of Energy Science and Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India); Nair, Pradeep R., E-mail: sumanshu@iitb.ac.in, E-mail: prnair@ee.iitb.ac.in [Department of Electrical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India)

    2015-09-21

    Despite the exciting recent research on perovskite based solar cells, the design space for further optimization and the practical limits of efficiency are not well known in the community. In this letter, we address these aspects through theoretical calculations and detailed numerical simulations. Here, we first provide the detailed balance limit efficiency in the presence of radiative and Auger recombination. Then, using coupled optical and carrier transport simulations, we identify the physical mechanisms that contribute towards bias dependent carrier collection, and hence low fill factors of current perovskite based solar cells. Our detailed simulations indicate that it is indeed possible to achieve efficiencies and fill factors greater than 25% and 85%, respectively, with near ideal super-position characteristics even in the presence of Auger recombination.

  9. Efficient transmission and characterization of Creutzfeldt-Jakob disease strains in bank voles.

    Romolo Nonno

    2006-02-01

    Full Text Available Transmission of prions between species is limited by the "species barrier," which hampers a full characterization of human prion strains in the mouse model. We report that the efficiency of primary transmission of prions from Creutzfeldt-Jakob disease patients to a wild rodent species, the bank vole (Clethrionomys glareolus, is comparable to that reported in transgenic mice carrying human prion protein, in spite of a low prion protein-sequence homology between man and vole. Voles infected with sporadic and genetic Creutzfeldt-Jakob disease isolates show strain-specific patterns of spongiform degeneration and pathological prion protein-deposition, and accumulate protease-resistant prion protein with biochemical properties similar to the human counterpart. Adaptation of genetic Creutzfeldt-Jakob disease isolates to voles shows little or no evidence of a transmission barrier, in contrast to the striking barriers observed during transmission of mouse, hamster, and sheep prions to voles. Our results imply that in voles there is no clear relationship between the degree of homology of the prion protein of the donor and recipient species and susceptibility, consistent with the view that the prion strain gives a major contribution to the species barrier. The vole is therefore a valuable model to study human prion diversity and, being susceptible to a range of animal prions, represents a unique tool for comparing isolates from different species.

  10. Efficient transmission and characterization of creutzfeldt-jakob disease strains in bank voles.

    2006-02-01

    Full Text Available Transmission of prions between species is limited by the "species barrier," which hampers a full characterization of human prion strains in the mouse model. We report that the efficiency of primary transmission of prions from Creutzfeldt-Jakob disease patients to a wild rodent species, the bank vole (Clethrionomys glareolus, is comparable to that reported in transgenic mice carrying human prion protein, in spite of a low prion protein-sequence homology between man and vole. Voles infected with sporadic and genetic Creutzfeldt-Jakob disease isolates show strain-specific patterns of spongiform degeneration and pathological prion protein-deposition, and accumulate protease-resistant prion protein with biochemical properties similar to the human counterpart. Adaptation of genetic Creutzfeldt-Jakob disease isolates to voles shows little or no evidence of a transmission barrier, in contrast to the striking barriers observed during transmission of mouse, hamster, and sheep prions to voles. Our results imply that in voles there is no clear relationship between the degree of homology of the prion protein of the donor and recipient species and susceptibility, consistent with the view that the prion strain gives a major contribution to the species barrier. The vole is therefore a valuable model to study human prion diversity and, being susceptible to a range of animal prions, represents a unique tool for comparing isolates from different species.

  11. The intracellular bacterium Wolbachia uses parasitoid wasps as phoretic vectors for efficient horizontal transmission.

    Muhammad Z Ahmed

    2015-02-01

    Full Text Available Facultative bacterial endosymbionts are associated with many arthropods and are primarily transmitted vertically from mother to offspring. However, phylogenetic affiliations suggest that horizontal transmission must also occur. Such horizontal transfer can have important biological and agricultural consequences when endosymbionts increase host fitness. So far horizontal transmission is considered rare and has been difficult to document. Here, we use fluorescence in situ hybridization (FISH and multi locus sequence typing (MLST to reveal a potentially common pathway of horizontal transmission of endosymbionts via parasitoids of insects. We illustrate that the mouthparts and ovipositors of an aphelinid parasitoid become contaminated with Wolbachia when this wasp feeds on or probes Wolbachia-infected Bemisia tabaci AsiaII7, and non-lethal probing of uninfected B. tabaci AsiaII7 nymphs by parasitoids carrying Wolbachia resulted in newly and stably infected B. tabaci matrilines. After they were exposed to infected whitefly, the parasitoids were able to transmit Wolbachia efficiently for the following 48 h. Whitefly infected with Wolbachia by parasitoids had increased survival and reduced development times. Overall, our study provides evidence for the horizontal transmission of Wolbachia between insect hosts by parasitic wasps, and the enhanced survival and reproductive abilities of insect hosts may adversely affect biological control programs.

  12. Transmission-grating spectrometer for highly efficient and high-resolution soft X-ray emission studies

    Yamane, Hiroyuki [Institute for Molecular Science and The Graduate University for Advanced Studies, Okazaki 444-8585 (Japan); Kosugi, Nobuhiro, E-mail: kosugi@ims.ac.jp [Institute for Molecular Science and The Graduate University for Advanced Studies, Okazaki 444-8585 (Japan); Hatsui, Takaki, E-mail: hatsui@spring8.or.jp [RIKEN SPring-8 Center, RIKEN, Hyogo 679-5148 (Japan)

    2013-06-15

    Highlights: ► We develop a highly efficient and high-resolution soft X-ray emission spectrometer. ► We combine a transmission grating, a Wolter type I mirror, and normal-incident CCD. ► X-ray emission resolution proves to be 15–34 meV in the photon energy of 60–100 eV. -- Abstract: A high-resolution soft X-ray emission spectrometer has been developed for site-specific electronic structure analysis of functional materials in the photon energy range of 50–600 eV on the in-vacuum undulator beamline BL3U of the UVSOR facility. In order to realize the high detection efficiency without sacrificing the energy resolution to the signal intensity, the present X-ray emission spectrometer adopts an optical design, which was originally adopted in the field of astrophysics such as Chandra X-ray observatory. This new-type X-ray emission spectrometer consists of a Wolter type I mirror, a freestanding transmission grating, and a charge coupled device (CCD) detector, allowing the focusing with 20 times larger acceptance angle (1.5 × 10{sup −3} sr) than commercially available compact spectrometers with reflection-type gratings such as VG-SCIENTA XES350. The X-ray emission energy resolution of 15–34 meV has successfully been achieved in the photon energy of 60–100 eV by using a transmission grating with the groove density of 5555 lines/mm.

  13. Time domain zero-padding based adaptive-PAM signal transmission with high spectral efficiency in IMDD optical communication system

    Zhang, Fangliu; He, Jing; Deng, Rui; Cheng, Yun; Xiao, Minlei; Chen, Lin

    2016-08-01

    In this paper, an adaptive pulse amplitude modulation (APAM) scheme is proposed and experimentally demonstrated in the intensity-modulation and direct-detection (IMDD) optical communications system. In the proposed scheme, the channel is divided into two sub-channels, and different PAM mapping can be chosen for different sub-channel according to the fading conditions. In addition, the 20-km standard single mode fiber (SSMF) transmission of 24 Gbit/s 16/4-APAM signal with the spectral efficiency (SE) up to 6 bit/s/Hz is experimentally demonstrated. The experiment results show that the bit error rate (BER) of the 16/4-APAM signal can be achieved less than 2.4e-2.

  14. Efficient reconstruction of transmission probabilities in a spreading process from partial observations

    Lokhov, Andrey Y

    2015-01-01

    An important problem of reconstruction of diffusion network and transmission probabilities from the data has attracted a considerable attention in the past several years. A number of recent papers introduced efficient algorithms for the estimation of spreading parameters, based on the maximization of the likelihood of observed cascades, assuming that the full information for all the nodes in the network is available. In this work, we focus on a more realistic and restricted scenario, in which only a partial information on the cascades is available: either the set of activation times for a limited number of nodes, or the states of nodes for a subset of observation times. To tackle this problem, we first introduce a framework based on the maximization of the likelihood of the incomplete diffusion trace. However, we argue that the computation of this incomplete likelihood is a computationally hard problem, and show that a fast and robust reconstruction of transmission probabilities in sparse networks can be achi...

  15. Efficient linear phase contrast in scanning transmission electron microscopy with matched illumination and detector interferometry.

    Ophus, Colin; Ciston, Jim; Pierce, Jordan; Harvey, Tyler R; Chess, Jordan; McMorran, Benjamin J; Czarnik, Cory; Rose, Harald H; Ercius, Peter

    2016-01-01

    The ability to image light elements in soft matter at atomic resolution enables unprecedented insight into the structure and properties of molecular heterostructures and beam-sensitive nanomaterials. In this study, we introduce a scanning transmission electron microscopy technique combining a pre-specimen phase plate designed to produce a probe with structured phase with a high-speed direct electron detector to generate nearly linear contrast images with high efficiency. We demonstrate this method by using both experiment and simulation to simultaneously image the atomic-scale structure of weakly scattering amorphous carbon and strongly scattering gold nanoparticles. Our method demonstrates strong contrast for both materials, making it a promising candidate for structural determination of heterogeneous soft/hard matter samples even at low electron doses comparable to traditional phase-contrast transmission electron microscopy. Simulated images demonstrate the extension of this technique to the challenging problem of structural determination of biological material at the surface of inorganic crystals. PMID:26923483

  16. Efficient linear phase contrast in scanning transmission electron microscopy with matched illumination and detector interferometry

    Ophus, Colin; Ciston, Jim; Pierce, Jordan; Harvey, Tyler R.; Chess, Jordan; McMorran, Benjamin J.; Czarnik, Cory; Rose, Harald H.; Ercius, Peter

    2016-02-01

    The ability to image light elements in soft matter at atomic resolution enables unprecedented insight into the structure and properties of molecular heterostructures and beam-sensitive nanomaterials. In this study, we introduce a scanning transmission electron microscopy technique combining a pre-specimen phase plate designed to produce a probe with structured phase with a high-speed direct electron detector to generate nearly linear contrast images with high efficiency. We demonstrate this method by using both experiment and simulation to simultaneously image the atomic-scale structure of weakly scattering amorphous carbon and strongly scattering gold nanoparticles. Our method demonstrates strong contrast for both materials, making it a promising candidate for structural determination of heterogeneous soft/hard matter samples even at low electron doses comparable to traditional phase-contrast transmission electron microscopy. Simulated images demonstrate the extension of this technique to the challenging problem of structural determination of biological material at the surface of inorganic crystals.

  17. Efficiency and the public interest: QF transmission and the Energy Policy Act of 1992

    Prior to the enactment of the Energy Policy Act of 1992 (Act), most Federal Energy Regulatory Commission (FERC or Commission) deliberations involving transmission services did not occur in transmission rate or service proceedings per se. The Commission conducted a number of general inquiries or studies of the subject, including setting the terms and conditions of transmission services as part of merger proceedings and open-quotes market-basedclose quotes pricing proceedings. With the passage of the Act, the FERC is likely to be asked to confront the advisability of requiring transmission services in a more direct manner. The Act permits open-quotes[a]ny electric utility, Federal power marketing agency, or any other person generating electrical energy for sale for resaleclose quotes to petition the Commission for a wheeling order. The FERC may order wheeling in accordance with section 212 of the Federal Power Act (FPA) and a finding that such wheeling would open-quotes otherwise be in the public interest.close quotes When compounded with the need to find that wheeling is in the public interest, the requirements set forth in section 212 are considerable. This article focuses on an important area of section 212 criteria, namely the interplay between between the public interest and economic efficiency criteria in the case of Public Utility Regulatory Policies Act of 1978 (PURPA) Qualifying Facilities (QF). Two recent proceedings in which the FERC considered the need to provide power transmission service guarantees for QFs are analyzed from the standpoint of public and private economic welfare. The two proceedings are the merger of Utah Power ampersand Light Company, PacifiCorp, PC/UP ampersand L Merging Corporation (Utah) and the Western Systems Power Pool application (WSPP)

  18. SVANET: A Smart Vehicular Ad Hoc Network for Efficient Data Transmission with Wireless Sensors

    Sahoo, Prasan Kumar; Chiang, Ming-Jer; Wu, Shih-Lin

    2014-01-01

    Wireless sensors can sense any event, such as accidents, as well as icy roads, and can forward the rescue/warning messages through intermediate vehicles for any necessary help. In this paper, we propose a smart vehicular ad hoc network (SVANET) architecture that uses wireless sensors to detect events and vehicles to transmit the safety and non-safety messages efficiently by using different service channels and one control channel with different priorities. We have developed a data transmission protocol for the vehicles in the highway, in which data can be forwarded with the help of vehicles if they are connected with each other or data can be forwarded with the help of nearby wireless sensors. Our data transmission protocol is designed to increase the driving safety, to prevent accidents and to utilize channels efficiently by adjusting the control and service channel time intervals dynamically. Besides, our protocol can transmit information to vehicles in advance, so that drivers can decide an alternate route in case of traffic congestion. For various data sharing, we design a method that can select a few leader nodes among vehicles running along a highway to broadcast data efficiently. Simulation results show that our protocol can outperform the existing standard in terms of the end to end packet delivery ratio and latency. PMID:25429409

  19. A high-efficiency power and data transmission system for biomedical implanted electronic devices

    Hamici, Zoubir; Itti, Roland; Champier, Jacques

    1996-02-01

    In biomedical engineering, inductive transcutaneous links can be used for power and data transfer between external systems and implanted electronic devices. The development of a micro-telemeter having a significant implantation depth needs a high-efficiency magnetic transcutaneous link. This paper presents a new system, which uses a multi-frequency load network for transmitter coil based on the class E power amplifier. At the carrier frequency used, the resistive load is influenced by the coupling of the coils and by the variation of the implant equivalent resistance. Modulating this latter between two rails permits one to modulate the amplitude of the external transmitter current and then to transmit internal data without the use of the classical implanted emitter design. Furthermore, the fact that the modulation index depends on the coupling factor, allows one to find the external coil's correct position using a position feedback loop. A complete study of the concept of digital data transmission by impedance modulation associated with a class E power amplifier is presented. Internal data transmission using this system yields a decrease of the internal electronic circuitry bulk and constitutes a high-efficiency energizing device. A theoretical investigation shows that the efficiency of the power transfer varies between 44 and 75% within a wide range of implantation depths (20 - 40 mm).

  20. Achievement-Relevant Personality: Relations with the Big Five and Validation of an Efficient Instrument.

    Briley, Daniel A; Domiteaux, Matthew; Tucker-Drob, Elliot M

    2014-05-01

    Many achievement-relevant personality measures (APMs) have been developed, but the interrelations among APMs or associations with the broader personality landscape are not well-known. In Study 1, 214 participants were measured on 36 APMs and a measure of the Big Five. Factor analytic results supported the convergent and discriminant validity of five latent dimensions: performance, mastery, self-doubt, effort, and intellectual investment. Conscientiousness, neuroticism, and openness to experience had the most consistent associations with APMs. We constructed a more efficient scale- the Multidimensional Achievement-Relevant Personality Scale (MAPS). In Study 2, we replicated the factor structure and external correlates of the MAPS in a sample of 359 individuals. Finally, we validated the MAPS with four indicators of academic performance and demonstrated incremental validity. PMID:24839374

  1. Achieving Efficient Channel Utilization for Data Communications in IEEE 802.11 WLAN

    ZHANG Liang; SHU Yantai

    2005-01-01

    In the IEEE 802. 11 protocol, the adoption of the exponential backoff technique leads to throughput performance strongly dependent on the initial contention window size and, most importantly, on the number of contending stations considered in the network. This paper proposes a simpie but accurate method to dynamically estimate the number of contending stations in a wireless local area network (WLAN). Based on estimation, all the mobile stations dynamically adjust the initial contention window in medium access control (MAC) layer to avoid collisions. The simulation results show that the proposed algorithm can achieve efficient channel utilization, higher system throughput, and better fairness performance.

  2. Call transmission efficiency in native and invasive anurans: competing hypotheses of divergence in acoustic signals.

    Llusia, Diego; Gómez, Miguel; Penna, Mario; Márquez, Rafael

    2013-01-01

    Invasive species are a leading cause of the current biodiversity decline, and hence examining the major traits favouring invasion is a key and long-standing goal of invasion biology. Despite the prominent role of the advertisement calls in sexual selection and reproduction, very little attention has been paid to the features of acoustic communication of invasive species in nonindigenous habitats and their potential impacts on native species. Here we compare for the first time the transmission efficiency of the advertisement calls of native and invasive species, searching for competitive advantages for acoustic communication and reproduction of introduced taxa, and providing insights into competing hypotheses in evolutionary divergence of acoustic signals: acoustic adaptation vs. morphological constraints. Using sound propagation experiments, we measured the attenuation rates of pure tones (0.2-5 kHz) and playback calls (Lithobates catesbeianus and Pelophylax perezi) across four distances (1, 2, 4, and 8 m) and over two substrates (water and soil) in seven Iberian localities. All factors considered (signal type, distance, substrate, and locality) affected transmission efficiency of acoustic signals, which was maximized with lower frequency sounds, shorter distances, and over water surface. Despite being broadcast in nonindigenous habitats, the advertisement calls of invasive L. catesbeianus were propagated more efficiently than those of the native species, in both aquatic and terrestrial substrates, and in most of the study sites. This implies absence of optimal relationship between native environments and propagation of acoustic signals in anurans, in contrast to what predicted by the acoustic adaptation hypothesis, and it might render these vertebrates particularly vulnerable to intrusion of invasive species producing low frequency signals, such as L. catesbeianus. Our findings suggest that mechanisms optimizing sound transmission in native habitat can play a less

  3. Energy efficiency enhancements for semiconductors, communications, sensors and software achieved in cool silicon cluster project

    Ellinger, Frank; Mikolajick, Thomas; Fettweis, Gerhard; Hentschel, Dieter; Kolodinski, Sabine; Warnecke, Helmut; Reppe, Thomas; Tzschoppe, Christoph; Dohl, Jan; Carta, Corrado; Fritsche, David; Tretter, Gregor; Wiatr, Maciej; Detlef Kronholz, Stefan; Mikalo, Ricardo Pablo; Heinrich, Harald; Paulo, Robert; Wolf, Robert; Hübner, Johannes; Waltsgott, Johannes; Meißner, Klaus; Richter, Robert; Michler, Oliver; Bausinger, Markus; Mehlich, Heiko; Hahmann, Martin; Möller, Henning; Wiemer, Maik; Holland, Hans-Jürgen; Gärtner, Roberto; Schubert, Stefan; Richter, Alexander; Strobel, Axel; Fehske, Albrecht; Cech, Sebastian; Aßmann, Uwe; Pawlak, Andreas; Schröter, Michael; Finger, Wolfgang; Schumann, Stefan; Höppner, Sebastian; Walter, Dennis; Eisenreich, Holger; Schüffny, René

    2013-07-01

    An overview about the German cluster project Cool Silicon aiming at increasing the energy efficiency for semiconductors, communications, sensors and software is presented. Examples for achievements are: 1000 times reduced gate leakage in transistors using high-fc (HKMG) materials compared to conventional poly-gate (SiON) devices at the same technology node; 700 V transistors integrated in standard 0.35 μm CMOS; solar cell efficiencies above 19% at e-Commerce applications; processors and corresponding data links with 40% and 70% energy savings, respectively, by adaption of clock frequency and supply voltage in less than 20 ns; clock generator chip with tunable frequency from 83-666 MHz and 0.62-1.6 mW dc power; 90 Gb/s on-chip link over 6 mm and efficiency of 174 fJ/mm; dynamic biasing system doubling efficiency in power amplifiers; 60 GHz BiCMOS frontends with dc power to bandwidth ratio of 0.17 mW/MHz; driver assistance systems reducing energy consumption by 10% in cars Contribution to the Topical Issue “International Semiconductor Conference Dresden-Grenoble - ISCDG 2012”, Edited by Gérard Ghibaudo, Francis Balestra and Simon Deleonibus.

  4. Highly efficient industrial large-area black silicon solar cells achieved by surface nanostructured modification

    Li, Ping; Wei, Yi; Zhao, Zengchao; Tan, Xin; Bian, Jiming; Wang, Yuxuan; Lu, Chunxi; Liu, Aimin

    2015-12-01

    Traditional black silicon solar cells show relatively low efficiencies due to the high surface recombination occurring at the front surfaces. In this paper, we present a surface modification process to suppress surface recombination and fabricate highly efficient industrial black silicon solar cells. The Ag-nanoparticle-assisted etching is applied to realize front surface nanostructures on silicon wafers in order to reduce the surface reflectance. Through a further tetramethylammonium hydroxide (TMAH) treatment, the carrier recombination at and near the surface is greatly suppressed, due to a lower surface dopant concentration after the surface modification. This modified surface presents a low reflectivity in a range of 350-1100 nm. Large-area solar cells with an average conversion efficiency of 19.03% are achieved by using the TMAH treatment of 30 s. This efficiency is 0.18% higher than that of standard silicon solar cells with pyramidal surfaces, and also a remarkable improvement compared with black silicon solar cells without TMAH modifications.

  5. Influence of the electrical design of offshore wind farms and of transmission lines on efficiency

    Santjer, F. [German Wind Energy Institute, Wilhelmshaven (Germany); Sobek, L.H. [Dortmund Univ. (Germany); Gerdes, G.J. [Deutsche WindGuard GmbH, Varel (Germany)

    2001-07-01

    The design of an offshore wind farm system influences the energy output and thus the efficiency of the wind farm. One of the aspects is the electrical design of the wind farm internal grid and of the transmission line between offshore wind farm and mainland grid. This paper shows the investigations of a simulated wind farm of 150 MW, consisting of 30 wind turbines of 5 MW. Different layouts of the internal wind farm network (ringed networks, radial networks, etc.) were compared. Also the voltage level of the internal wind farm network was changed (e.g. 6 kV, 20 kV, 30 kV). Another influence, given by the reactive power compensation units (central compensation unit and compensation units at the wind turbines) was investigated. For the transmission line between the offshore wind farm and the mainland grid a High Voltage DC (HVDC) connection was used. For this transmission line different voltage levels were compared. At first an overview of the offshore situation and plannings in Germany is given.

  6. A comprehensive approach for computation and implementation of efficient electricity transmission network charges

    This paper presents a comprehensive design of electricity transmission charges that are meant to recover regulated network costs. In addition, these charges must be able to meet a set of inter-related objectives. Most importantly, they should encourage potential network users to internalize transmission costs in their location decisions, while interfering as least as possible with the short-term behaviour of the agents in the power system, since this should be left to regulatory instruments in the operation time range. The paper also addresses all those implementation issues that are essential for the sound design of a system of transmission network charges: stability and predictability of the charges; fair and efficient split between generation and demand charges; temporary measures to account for the low loading of most new lines; number and definition of the scenarios to be employed for the calculation and format of the final charges to be adopted: capacity, energy or per customer charges. The application of the proposed method is illustrated with a realistic numerical example that is based on a single scenario of the 2006 winter peak in the Spanish power system.

  7. TORQUE CAPACITY AND CONTACT EFFICIENCY OF A HALF TOROIDAL CONTINUOUSLY VARLABLE TRANSMISSIONS

    Nabil Abdulla Attia; Qin Datong; Shi Wankai; Amir Ibrahim Ali

    2004-01-01

    The automotive industry is seeking new concepts for a continuously variable transmission (CVT) in the driveline. One possible solution for a CVT design is half toroidal traction drive, providing a high torque capacity with quick ratio change. An analytical study on the contact points of the half toroidal CVT has been detailed. The shapes of the contact areas among the input disk, power roller and output disk are considered ellipses. Mathematical equations for estimating the torque capacity, power loss due to spin action, and contact efficiency of the elliptical contacts of the half toroidal CVT are formulated and expressed in the form of integrals which can be readily evaluated by numerical scheme. The contact efficiency calculations of the half toroidal CVT have been developed for the proper spin point locations under the effect of system parameters. Numerical results are presented in graphical forms for considered parameters, which can help the designer to select the proper system parameters to minimize the undesirable spin effects.

  8. Research of Efficiency of the Data Transmission Telecommunication Systems with Limited by the Frequency Stripe and Power

    Gorbatyy, Ivan

    2010-01-01

    the efficiency of the data transmission telecommunication systems with limited by frequency stripe of telecommunication channel and signal power in channel with the use of modern kinds of signal modulation was explored. The results of efficiency of the systems at the concrete kinds of modulation were got. Recommendations in relation to application of definite kinds of modulation in the data transmission telecommunication systems were given.

  9. Effects of evacuation assistant’s leading behavior on the evacuation efficiency: Information transmission approach

    Wang, Xiao-Lu; Guo, Wei; Zheng, Xiao-Ping

    2015-07-01

    Evacuation assistants are expected to spread the escape route information and lead evacuees toward the exit as quickly as possible. Their leading behavior influences the evacuees’ movement directly, which is confirmed to be a decisive factor of the evacuation efficiency. The transmission process of escape information and its function on the evacuees’ movement are accurately presented by the proposed extended dynamic communication field model. For evacuation assistants and evacuees, their sensitivity parameter of static floor field (SFF), , and , are fully discussed. The simulation results indicate that the appropriate is associated with the maximum of evacuees. The optimal combinations of and were found to reach the highest evacuation efficiency. There also exists an optimal value for evacuation assistants’ information transmission radius. Project supported by the National Basic Research Program of China (Grant No. 2011CB706900), the National Natural Science Foundation of China (Grant Nos. 71225007 and 71203006), the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (Grant No. 2012BAK13B06), the Humanities and Social Sciences Project of the Ministry of Education of China (Grant Nos. 10YJA630221 and 12YJCZH023), and the Beijing Philosophy and Social Sciences Planning Project of the Twelfth Five-Year Plan, China (Grant Nos. 12JGC090 and 12JGC098).

  10. Efficient transmission of subthreshold signals in complex networks of spiking neurons.

    Joaquin J Torres

    Full Text Available We investigate the efficient transmission and processing of weak, subthreshold signals in a realistic neural medium in the presence of different levels of the underlying noise. Assuming Hebbian weights for maximal synaptic conductances--that naturally balances the network with excitatory and inhibitory synapses--and considering short-term synaptic plasticity affecting such conductances, we found different dynamic phases in the system. This includes a memory phase where population of neurons remain synchronized, an oscillatory phase where transitions between different synchronized populations of neurons appears and an asynchronous or noisy phase. When a weak stimulus input is applied to each neuron, increasing the level of noise in the medium we found an efficient transmission of such stimuli around the transition and critical points separating different phases for well-defined different levels of stochasticity in the system. We proved that this intriguing phenomenon is quite robust, as it occurs in different situations including several types of synaptic plasticity, different type and number of stored patterns and diverse network topologies, namely, diluted networks and complex topologies such as scale-free and small-world networks. We conclude that the robustness of the phenomenon in different realistic scenarios, including spiking neurons, short-term synaptic plasticity and complex networks topologies, make very likely that it could also occur in actual neural systems as recent psycho-physical experiments suggest.

  11. Evidence of more efficient whistler-mode transmission during periods of increased magnetic activity

    N. R. Thomson

    Full Text Available In a previous study it was reported that whistler- mode signals received at Faraday, Antarctica (65°S,64°W and Dunedin, New Zealand (46°S,171°E with entry regions in Pacific longitudes (typically from the VLF transmitter NLK, Seattle, USA showed an increase in transmission of wave energy as magnetic activity increased. However, signals with entry regions in Atlantic longitudes (typically from the NSS transmitter, Annapolis, USA did not appear to show such a relationship. This paper reports the results of a study of the same two longitude ranges but with the opposite transmitter providing additional whistler-mode signal information, with L-values in the range 1.8–2.6. Transmissions from NLK once again indicate a relationship between the transmission of wave energy and magnetic activity even though the signals were propagating in Atlantic longitudes, not Pacific. Any trend in NSS events observed at Dunedin was obscured by a limited range of magnetic activity, and duct exit regions so close to the receiver that small-scale excitation effects appeared to be occurring. However, by combining data from both longitudes, i.e Pacific and Atlantic, and using only ducts with exit regions that were >500km from the receiver, NSS events were found to show the same trend as NLK events. No significant longitude-dependent or transmitter-dependent variations in duct efficiency could be detected. Duct efficiency increases by a factor of about 30 with Kp=2–8 and this result is discussed in terms of changes in wave-particle interactions and duct size.

  12. Nanosized free-energy transducer F1-ATPase achieves 100% efficiency at finite time operation

    Toyabe, Shoichi

    2012-01-01

    The free-energy transduction at 100% efficiency is not prohibited by thermodynamic laws. However, it is usually reached only at the quasi-static limit such as the macroscopic piston pulled or pushed at the infinitely slow velocity. If we operate the piston quickly, turbulence is inevitable and irreversible heat dissipates through the microscopic degrees of freedom. Here, we evaluated the work performed by the nano-sized biological free-energy transducer F1-ATPase by single-molecule experiments on the basis of nonequilibrium theory. We show that the F1-ATPase achieves a nearly 100% free-energy conversion efficiency even far from quasistatic process for both the mechanical-to-chemical and chemical-to-mechanical transductions. Such a high efficiency at a finite-time operation is not expected for macroscopic engines and highlights a remarkable property of the nano-sized engines working in the energy scale of k_{B}T. Some of the microscopic degrees of freedom may not be hidden but accessible to the F1-ATPase. Henc...

  13. Energy efficiency achievements in China's industrial and transport sectors: How do they rate?

    China is experiencing intensified industrialisation and motorisation. In the world's largest emerging economy, energy efficiency is expected to play a critical role in the ever-rising demand for energy. Based on factual overviews and numerical analysis, this article carries out an in-depth investigation into the effectiveness of policies announced or implemented in recent decades targeted at energy conservation in the energy intensive manufacturing and transportation sectors. It highlights nine energy intensive sectors that achieved major improvements in their energy technology efficiency efforts. Under the umbrella of the 11th Five-Year Plan, these sectors' performances reflect the effectiveness of China's energy conservation governance. Numerous actions have been taken in China to reduce the road transport sector's demand for energy and its GHG emissions by implementing fuel economy standards, promoting advanced energy efficient vehicles, and alternative fuels. Coal-based energy saving technologies, especially industrial furnace technologies, are critical for China's near and medium-term energy saving. In the long run, renewable energy development and expanding the railway transport system are the most effective ways to reduce energy use and GHG emissions in China. Fuel economy standards could reduce oil consumption and GHGs by 34–35 per cent. - Highlights: • This article makes an investigation into the effectiveness of energy conservation policies in China. • Efficiency improvement reflects the effective governance of energy conservation in China. • Numerous actions have been taken to reduce the road transport sector's demand for energy. • Coal-based energy saving technologies are critical for China's near and medium-term energy saving. • In the long run, renewable energy and expanding the railway transport system are the most effective ways

  14. Assurance of energy efficiency and data security for ECG transmission in BASNs.

    Ma, Tao; Shrestha, Pradhumna Lal; Hempel, Michael; Peng, Dongming; Sharif, Hamid; Chen, Hsiao-Hwa

    2012-04-01

    With the technological advancement in body area sensor networks (BASNs), low cost high quality electrocardiographic (ECG) diagnosis systems have become important equipment for healthcare service providers. However, energy consumption and data security with ECG systems in BASNs are still two major challenges to tackle. In this study, we investigate the properties of compressed ECG data for energy saving as an effort to devise a selective encryption mechanism and a two-rate unequal error protection (UEP) scheme. The proposed selective encryption mechanism provides a simple and yet effective security solution for an ECG sensor-based communication platform, where only one percent of data is encrypted without compromising ECG data security. This part of the encrypted data is essential to ECG data quality due to its unequally important contribution to distortion reduction. The two-rate UEP scheme achieves a significant additional energy saving due to its unequal investment of communication energy to the outcomes of the selective encryption, and thus, it maintains a high ECG data transmission quality. Our results show the improvements in communication energy saving of about 40%, and demonstrate a higher transmission quality and security measured in terms of wavelet-based weighted percent root-mean-squared difference. PMID:22231147

  15. A study on improvements of inspection efficiency with remote transmission of inspection data

    Current information networks technology brought secure and convenient condition of information transmission, so that inspectorates intend to apply such technology to optimize current inspection efforts. IAEA established the Remote Monitoring Project (RMP) in 1996 and started to draft safeguards concepts, and approaches to refer the implementation of remote monitoring technology and to compromise with relationship between current inspection activities and the remote monitoring technologies. Although communications costs and conditions of secured communication should be further investigated, the technologies would have a possibility to reduce current inspection efforts. We would face at the step to study on the several issues such as what measures could be candidate to use, how much cost we needs, what kind of technical risks would be concerned, further improvements could be achieved by comparison with current inspection costs and effectiveness. This paper reports on the expectation points and relevant technical attention points which are related to apply unattended inspection system with remote data transmission to the flows and inventory verification of item and bulk facility, respectively, in order to improve inspection efforts. (author)

  16. Calibration of STUD+ parameters to achieve optimally efficient broadband adiabatic decoupling in a single transient

    Bendall; Skinner

    1998-10-01

    for a single sech/tanh pulse. Residual splitting of the centerband, normally associated with incomplete or inefficient decoupling, is not seen in sech/tanh decoupling and therefore cannot be used as a measure of adiabatic decoupling efficiency. The calibrated experimental performance levels achieved in this study are within 20% of theoretical performance levels derived previously for ideal sech/tanh decoupling at high power, indicating a small scope for further improvement at practical RF power levels. The optimization procedures employed here will be generally applicable to any good combination of adiabatic inversion pulse and phase cycle. Copyright 1998 Academic Press. PMID:9761708

  17. On the Efficiency of the New York Independent System OperatorMarket for Transmission Congestion Contracts

    Siddiqui, Afzal S.; Bartholomew, Emily S.; Marnay, Chris; Oren,Shmuel S.

    2003-04-01

    The physical nature of electricity generation and deliverycreates special problems for the design of efficient markets, notably theneed to manage delivery in real time and the volatile congestion andassociated costs that result. Proposals for the operation of thederegulated electricity industry tend towards one of two paradigms:centralized and decentralized. Transmission congestion management can beimplemented in the more centralized point-to-point approach, a in NewYork state, where derivative transmission congestion contracts (TCCs) aretraded, or in the more decentralized flowgate-based approach. While it iswidely accepted that theoretically TCCs have attractive properties ashedging instruments against congestion cost uncertainty, whetherefficient markets for them can be established in practice has beenquestioned. Based on an empirical analysis of publicly available datafrom years 2000 and 2001, it appears that New York TCCs providedmarketparticipants with a potentially effective hedge against volatilecongestion rents. However, the prices paid for TCCs systematicallydiverged from the resulting congestion rents for distant locations and athigh prices. The price paid for the hedge not being in line with thecongestion rents, i.e. unreasonably high risk premiums are being paid,suggests an inefficient market. The low liquidity of TCC markets and thedeviation of TCC feasibility requirements from actual energy flows arepossible explanations.

  18. Nonlinear inverse synthesis for high spectral efficiency transmission in optical fibers

    Le, Son Thai; Turitsyn, Sergei K

    2014-01-01

    In linear communication channels, spectral components (modes) defined by the Fourier transform of the signal propagate without interactions with each other. In certain nonlinear channels, such as the one modelled by the classical nonlinear Schr\\"odinger equation, there are nonlinear modes (nonlinear signal spectrum) that also propagate without interacting with each other and without corresponding nonlinear cross talk; effectively, in a linear manner. Here, we describe in a constructive way how to introduce such nonlinear modes for a given input signal. We investigate the performance of the nonlinear inverse synthesis (NIS) method, in which the information is encoded directly onto the continuous part of the nonlinear signal spectrum. This transmission technique, combined with the appropriate distributed Raman amplification, can provide an effective eigenvalue division multiplexing with high spectral efficiency, thanks to highly suppressed channel cross talk. The proposed NIS approach can be integrated with any...

  19. An Efficient Channel Model for OFDM and Time Domain Single Carrier Transmission Using Impulse Responses

    Tariq Jamil Saifullah Khanzada

    2012-01-01

    Full Text Available The OFDM (Orthogonal Frequency Division Multiplexing is well-known, most utilized wideband communication technique of the current era. SCT (Single Carrier Transmission provides equivalent performance in time domain while decision equalizer is implemented in frequency domain. SCT annihilates the ICT (Inter Carrier Interference and the PAPR (Peak to Average Power Ratio which is inherent to OFDM and degrades its performance in time varying channels. An efficient channel model is presented in this contribution, to implement OFDM and SCT in time domain using impulse responses. Both OFDM and SCT models are derived dialectically to model the channel impulse responses. Our model enhances the performance of time domain SCT compared with OFDM and subsides the PAPR and ICI problems of OFDM. SCT is implemented at symbol level contained in blocks. Simulation results implementing Digital Radio Monadiale (DRM assert the performance gain of SCT over OFDM.

  20. Transport Schemes for Fiber-Wireless Technology: Transmission Performance and Energy Efficiency

    Christina Lim

    2014-04-01

    Full Text Available Fiber-wireless technology has been actively researched as a potential candidate for next generation broadband wireless signal distribution. Despite the popularity, this hybrid scheme has many technical challenges that impede the uptake and commercial deployment. One of the inherent issues is the transport of the wireless signals over a predominantly digital optical network in today’s telecommunication infrastructure. Many different approaches have been introduced and demonstrated with digitized RF transport of the wireless signals being the most compatible with the existing optical fiber networks. In this paper, we review our work in the area of digitized RF transport to address the inherent issues related to analog transport in the fiber-wireless links and compare the transmission performance and energy efficiency with the other transport strategies.

  1. High-efficiency blazed transmission gratings for high-resolution soft x-ray spectroscopy

    Heilmann, Ralf K.; Bruccoleri, Alexander R.; Schattenburg, Mark L.

    2015-09-01

    High-resolution spectroscopy of astrophysical sources is the key to gaining a quantitative understanding of the history, dynamics, and current conditions of the cosmos. A large-area (> 1,000 cm2), high resolving power (R = λ/Δλ> 3000) soft x-ray grating spectrometer (XGS) that covers the lines of C, N, O, Ne and Fe ions is the ideal tool to address a number of high-priority science questions from the 2010 Decadal Survey, such as the connection between super-massive black holes and large-scale structure via cosmic feedback, the evolution of large- scale structure, the behavior of matter at high densities, and the conditions close to black holes. While no grating missions or instruments are currently approved, an XGS aboard a potential future X-ray Surveyor could easily surpass the above performance metrics. To improve the chances for future soft x-ray grating spectroscopy missions or instruments, grating technology has to progress and advance to higher Technology Readiness Levels (TRLs). To that end we have developed Critical-Angle Transmission (CAT) gratings that combine the advantages of blazed reflection gratings (high efficiency, use of higher diffraction orders) with those of conventional transmission gratings (low mass, relaxed alignment tolerances and temperature requirements, high transparency at higher energies). A CAT grating-based spectrometer can provide performance 1-2 orders of magnitude better than current grating instruments on Chandra and Newton-XMM with minimal resource requirements. At present we have fabricated large-area freestanding CAT gratings with narrow integrated support structures from silicon-on- insulator wafers using advanced lithography and a combination of deep reactive-ion and wet etching. Our latest x-ray test results show record high absolute diffraction efficiencies in blazed orders in excess of 30% with room for improvement.

  2. Assessment of microcrystal quality by transmission electron microscopy for efficient serial femtosecond crystallography.

    Barnes, Christopher O; Kovaleva, Elena G; Fu, Xiaofeng; Stevenson, Hilary P; Brewster, Aaron S; DePonte, Daniel P; Baxter, Elizabeth L; Cohen, Aina E; Calero, Guillermo

    2016-07-15

    Serial femtosecond crystallography (SFX) employing high-intensity X-ray free-electron laser (XFEL) sources has enabled structural studies on microcrystalline protein samples at non-cryogenic temperatures. However, the identification and optimization of conditions that produce well diffracting microcrystals remains an experimental challenge. Here, we report parallel SFX and transmission electron microscopy (TEM) experiments using fragmented microcrystals of wild type (WT) homoprotocatechuate 2,3-dioxygenase (HPCD) and an active site variant (H200Q). Despite identical crystallization conditions and morphology, as well as similar crystal size and density, the indexing efficiency of the diffraction data collected using the H200Q variant sample was over 7-fold higher compared to the diffraction results obtained using the WT sample. TEM analysis revealed an abundance of protein aggregates, crystal conglomerates and a smaller population of highly ordered lattices in the WT sample as compared to the H200Q variant sample. While not reported herein, the 1.75 Å resolution structure of the H200Q variant was determined from ∼16 min of beam time, demonstrating the utility of TEM analysis in evaluating sample monodispersity and lattice quality, parameters critical to the efficiency of SFX experiments. PMID:26944553

  3. Evaluation of investment efficiency in the power transmission system considering the requirements of continuity and quality of electric power supply

    Power generation and transmission system is a physically and technically unitary system which requires a certain degree of hierarchical coordination and monitoring of consumer supply so that the following conditions to be satisfied: operation at the frequency and voltage parameters within the design variation limits; continuous power and electricity supply in order to meet the consumer demand; efficient operation of power generation, transmission and distribution system so that the process be both costly effective and competitive. The paper presents the requirements and directions in developing of the exiting power transmission system and the related problems of investment policy. (author). 1 fig., 1 tab.; 5 refs

  4. Modeling an aggressive energy-efficiency scenario in long-range load forecasting for electric power transmission planning

    Highlights: • Improved representation of end-use energy efficiency is needed for load forecasting. • An emergent application is long-range electric power transmission planning. • A “hybrid” econometric-technology forecasting approach incorporates efficiency. • A high efficiency scenario was created for Western U.S. transmission planning. • Significant load-growth reductions from increased end-use efficiency are possible. - Abstract: Improving the representation of end-use energy efficiency, and of the effects of policies and programs to promote it, is an emergent priority for electricity load forecasting models and methods. This paper describes a “hybrid” load forecasting approach combining econometric and technological elements that is designed to meet this need, in a novel application to long-run electric power transmission planning in the western United States. A twenty-year load forecast incorporating significant increases in energy-efficiency programs and policies across multiple locations was developed in order to assess the potential of efficiency to reduce load growth and requirements for expanded transmission capacity. Load forecasting and transmission planning background is summarized, the theoretical and empirical aspects of the hybrid methodology described, and the assumptions, structure, data development, and results of the aggressive efficiency scenario are presented. The analysis shows that substantial electricity savings are possible in this scenario in most residential and commercial end-uses, and in the industrial sector, with magnitudes depending upon the specific end-use as well as upon the geographic location of the utility or other entity providing the electricity

  5. A method to improve data transmission efficiency of non-cabled seismographs

    Zheng, F.; Lin, J.; Huaizhu, Z.; Yang, H.

    2012-12-01

    The non-cable self-locating seismograph developed by College of Instrumentation and Electrical Engineering, Jilin University integrates in-built battery, storage, WIFI, GPS and precision data acquisition. It is suitable for complex terrains which are typically not well addressed by cabled telemetric seismic instruments, such as mountains, swamps, and rivers. Moreover, it provides strong support for core functions such as long-term observation, wired and wireless data transmission, self-positioning and precision clock synchronization. The non-cable seismograph supports time window and continuous data acquisition. When the sampling time is long and sampling rate is high, a huge amount of original seismic data will be stored in the non-cable seismograph. As a result, it usually takes a long time—sometimes too long to be acceptable—to recover data in quasi real-time using wireless technology in resource exploration, especially in complex terrains. Furthermore, a large part of the recovered data is useless noise and only a small percentage is useful. For example, during the exploration experiment of a Chinese mine on July 12 and 14, 2012, we used 20 non-cable seismographs, each of them has 4 tracts. With a total of 80 tracts, 36GB data is collected over two data collecting sessions. 80 shot points were laid, each point lasting 4 seconds. As such the volume of valid data was about 100MB. That means only 0.3% of the total data was valid. At a wired data recovery rate of 200Mbps, 0.4 hours was needed to transmit all data completely. It takes even longer if one wish to review data on the spot by relying on a wireless data transmission rate of 10Mbps.A storage-type non-cable seismograph can store the collected data into several data files, and if one knows the source trigger time and vibration duration, it would be faster to collect data, thus improving data transmission efficiency. To this end, a triggering station is developed. It is one type of non-cable seismograph

  6. Wolbachia utilize host actin for efficient maternal transmission in Drosophila melanogaster.

    Irene L G Newton

    2015-04-01

    Full Text Available Wolbachia pipientis is a ubiquitous, maternally transmitted bacterium that infects the germline of insect hosts. Estimates are that Wolbachia infect nearly 40% of insect species on the planet, making it the most prevalent infection on Earth. The bacterium, infamous for the reproductive phenotypes it induces in arthropod hosts, has risen to recent prominence due to its use in vector control. Wolbachia infection prevents the colonization of vectors by RNA viruses, including Drosophila C virus and important human pathogens such as Dengue and Chikungunya. Here we present data indicating that Wolbachia utilize the host actin cytoskeleton during oogenesis for persistence within and transmission between Drosophila melanogaster generations. We show that phenotypically wild type flies heterozygous for cytoskeletal mutations in Drosophila profilin (chic(221/+ and chic(1320/+ or villin (qua(6-396/+ either clear a Wolbachia infection, or result in significantly reduced infection levels. This reduction of Wolbachia is supported by PCR evidence, Western blot results and cytological examination. This phenotype is unlikely to be the result of maternal loading defects, defects in oocyte polarization, or germline stem cell proliferation, as the flies are phenotypically wild type in egg size, shape, and number. Importantly, however, heterozygous mutant flies exhibit decreased total G-actin in the ovary, compared to control flies and chic(221 heterozygous mutants exhibit decreased expression of profilin. Additionally, RNAi knockdown of profilin during development decreases Wolbachia titers. We analyze evidence in support of alternative theories to explain this Wolbachia phenotype and conclude that our results support the hypothesis that Wolbachia utilize the actin skeleton for efficient transmission and maintenance within Drosophila.

  7. Energy-Efficient Transmission Strategy by Using Optimal Stopping Approach for Mobile Networks

    Peng, Ying; Wang, Gaocai; Wang, Nao

    2016-01-01

    In mobile networks, transmission energy consumption dominates the major part of network energy consumption. To reduce energy consumption for data transmission is an important topic for constructing green mobile networks. According to Shannon formula, when the transmission power is constant, the better the channel quality is, the greater the transmission rate is. Then, more data will be delivered in a given period. And energy consumption per bit data transmitted will be reduced. Because channe...

  8. Experimental demonstration of high spectral-efficiency transmission with a novel non-interferometric vector modulator and custom DSP algorithms for coherent PON architectures

    Lazarou, I.; Spatharakis, C.; Katopodis, V.; Dris, S.; Bakopoulos, P.; Schrenk, B.; Avramopoulos, H.

    2013-12-01

    We demonstrate a flexible multi-format vector modulator for coherent passive optical network (PON) architectures based on a non-interferometric cascade of a Semiconductor Optical Amplifier (SOA) and an Electro-Absorption Modulator (EAM) that exhibits increased simplicity and high energy-efficiency at low cost. 12- and 16- Quadrature Amplitude Modulation (QAM) constellations are generated, achieving modulation efficiencies of 3.6 and 4 bits/symbol respectively. The presented results demonstrate successful transmission over 25 km of fiber below the Forward Error Correction (FEC) limit, with sufficient compatible loss-budgets, making the proposed modulator concept an attractive candidate for urban network deployments, where high user density demands spectrally efficient formats. In addition, we describe the operation principle of the proposed modulator in detail and finally, the complete set of the digital signal processing (DSP) functionalities and algorithms that follow the standard coherent detection scheme is given, emphasizing on novel methods for QAM signal demodulation with uncommon constellation diagrams.

  9. Simple and efficient way of speeding up transmission calculations with k-point sampling

    Falkenberg, Jesper Toft; Brandbyge, Mads

    2015-01-01

    The transmissions as functions of energy are central for electron or phonon transport in the Landauer transport picture. We suggest a simple and computationally "cheap" post-processing scheme to interpolate transmission functions over k-points to get smooth well-converged average transmission fun...

  10. An Energy-Efficient Link Layer Protocol for Reliable Transmission over Wireless Networks

    Iqbal Adnan

    2009-01-01

    Full Text Available In multihop wireless networks, hop-by-hop reliability is generally achieved through positive acknowledgments at the MAC layer. However, positive acknowledgments introduce significant energy inefficiencies on battery-constrained devices. This inefficiency becomes particularly significant on high error rate channels. We propose to reduce the energy consumption during retransmissions using a novel protocol that localizes bit-errors at the MAC layer. The proposed protocol, referred to as Selective Retransmission using Virtual Fragmentation (SRVF, requires simple modifications to the positive-ACK-based reliability mechanism but provides substantial improvements in energy efficiency. The main premise of the protocol is to localize bit-errors by performing partial checksums on disjoint parts or virtual fragments of a packet. In case of error, only the corrupted virtual fragments are retransmitted. We develop stochastic models of the Simple Positive-ACK-based reliability, the previously-proposed Packet Length Optimization (PLO protocol, and the SRVF protocol operating over an arbitrary-order Markov wireless channel. Our analytical models show that SRVF provides significant theoretical improvements in energy efficiency over existing protocols. We then use bit-error traces collected over different real networks to empirically compare the proposed and existing protocols. These experimental results further substantiate that SRVF provides considerably better energy efficiency than Simple Positive-ACK and Packet Length Optimization protocols.

  11. System Virtualization and Efficient ID Transmission Method for RFID Tag Infrastructure Network

    Kuribayashi, Shin-ichi

    2010-01-01

    The use of RFID tag which identifies a thing and an object will be expanded with progress of ubiquitous society, and it is necessary to study how to construct RFID network system as a social infrastructure like the Internet. First, this paper proposes the virtualization method of RFID tag network system to enable the same physical RFID network system to be used by multiple different service systems. The system virtualization not only reduces the system cost but also can dramatically reduce the installation space of physical readers and the operation cost. It is proposed that all equipments in the RFID network system except RFID tag could be shared with the conventional virtual technologies. Then, this paper proposes the conditional tag ID processing and the efficient tag ID transmission method which can greatly reduce the processing time and processing load in RFID tag Infrastructure network The conditional tag ID processing allows that tag ID is valid only at a certain time zone of day or in a certain area. ...

  12. Influence of injection beam emittance on beam transmission efficiency in a cyclotron

    Kurashima, Satoshi, E-mail: kurashima.satoshi@jaea.go.jp; Kashiwagi, Hirotsugu; Miyawaki, Nobumasa; Yoshida, Ken-Ichi; Okumura, Susumu [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2014-02-15

    The JAEA AVF cyclotron accelerates various kinds of high-energy ion beams for research in biotechnology and materials science. Beam intensities of an ion species of the order of 10{sup −9}–10{sup −6} ampere are often required for various experiments performed sequentially over a day. To provide ion beams with sufficient intensity and stability, an operator has to retune an ion source in a short time. However, the beam intensity downstream of the cyclotron rarely increases in proportion to the intensity at the ion source. To understand the cause of this beam behavior, transmission efficiencies of a {sup 12}C{sup 5+} beam from an electron cyclotron resonance ion source to the cyclotron were measured for various conditions of the ion source. Moreover, a feasible region for acceleration in the emittance of the injection beam was clarified using a transverse-acceptance measuring system. We confirmed that the beam emittance and profile were changed depending on the condition of the ion source and that matching between the beam emittance and the acceptance of the cyclotron was degraded. However, after fine-tuning to improve the matching, beam intensity downstream of the cyclotron increased.

  13. A vacuum sealed high emission current and transmission efficiency carbon nanotube triode

    Di, Yunsong; Wang, Qilong; Zhang, Xiaobing; Lei, Wei; Du, Xiaofei; Yu, Cairu

    2016-04-01

    A vacuum sealed carbon nanotubes (CNTs) triode with a concave and spoke-shaped Mo grid is presented. Due to the high aperture ratio of the grid, the emission current could be modulated at a relatively high electric field. Totally 75mA emission current has been obtained from the CNTs cathode with the average applied field by the grid shifting from 8 to 13 V/μm. Whilst with the electron transmission efficiency of the grid over 56%, a remarkable high modulated current electron beam over 42mA has been collected by the anode. Also contributed by the high aperture ration of the grid, desorbed gas molecules could flow away from the emission area rapidly when the triode has been operated at a relative high emission current, and finally collected by a vacion pump. The working pressure has been maintained at ˜1 × 10-7 Torr, seldom spark phenomena occurred. Nearly perfect I-V curve and corresponding Fowler-Nordheim (FN) plot confirmed the accuracy of the measured data, and the emission current was long term stable and reproducible. Thusly, this kind of triode would be used as a high-power electron source.

  14. Management Methods for Achieving Faster and Higher Energy Efficiency for End Users

    Zēbergs, V; Zeltiņš, N; Puikevica-Puikevska, I; Silantjeva, I; Grackova, L

    2008-01-01

    The paper reflects investigations into the management methods for raising the efficiency of the processes of the use of energy under the conditions of Latvia. It justifies the fact that the model ISO 14001 of the ecological management system can be used for the management of the processes of raising energy efficiency. The impact of the energy efficiency management system is shown on raising the energy efficiency of an industrial enterprise. Certification of the energy efficienc...

  15. Blazed high-efficiency x-ray diffraction via transmission through arrays of nanometer-scale mirrors.

    Heilmann, Ralf K; Ahn, Minseung; Gullikson, Eric M; Schattenburg, Mark L

    2008-06-01

    Diffraction gratings are ubiquitous wavelength dispersive elements for photons as well as for subatomic particles, atoms, and large molecules. They serve as enabling devices for spectroscopy, microscopy, and interferometry in numerous applications across the physical sciences. Transmission gratings are required in applications that demand high alignment and figure error tolerances, low weight and size, or a straight-through zero-order beam. However, photons or particles are often strongly absorbed upon transmission, e.g., in the increasingly important extreme ultraviolet (EUV) and soft x-ray band, leading to low diffraction efficiency. We demonstrate the performance of a critical-angle transmission (CAT) grating in the EUV and soft x-ray band that for the first time combines the advantages of transmission gratings with the superior broadband efficiency of blazed reflection gratings via reflection from nanofabricated periodic arrays of atomically smooth nanometer-thin silicon mirrors at angles below the critical angle for total external reflection. The efficiency of the CAT grating design is not limited to photons, but also opens the door to new, sensitive, and compact experiments and applications in atom and neutron optics, as well as for the efficient diffraction of electrons, ions, or molecules. PMID:18545579

  16. A STUDY OF RELATIONSHIPAMONG TEACHING EFFICIENCY , ATTITUDE TOWARDS TEACHING PROFESSION AND ACEDEMIC ACHIEVEMENT OF B.ED. STUDENTS

    PRADIPKUMAR NAVNITLAL JAISWAL

    2013-01-01

    Only 223 student-teachers were included in this study out of which 94 male and 129 female trainees randomly selected, and were administered Ahuliwalia's “Attitude Inventory” and Deva's 'Teaching Efficiency Scale' Academic achievement divisions obtained by the student-teachers from bachelor degree examination onwards. The data was collected from student-teachers of three training colleges of Sabarkantha district, Gujarat Stat. The collected data was analysed mean, S.D. and Co-efficient of corr...

  17. Time and Energy Efficient Relay Transmission for Multi-Hop Wireless Sensor Networks

    Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

    2016-01-01

    The IEEE 802.15.4 standard is widely recognized as one of the most successful enabling technologies for short range low rate wireless communications and it is used in IoT applications. It covers all the details related to the MAC and PHY layers of the IoT protocol stack. Due to the nature of IoT, the wireless sensor networks are autonomously self-organized networks without infrastructure support. One of the issues in IoT is the network scalability. To address this issue, it is necessary to support the multi-hop topology. The IEEE 802.15.4 network can support a star, peer-to-peer, or cluster-tree topology. One of the IEEE 802.15.4 topologies suited for the high predictability of performance guarantees and energy efficient behavior is a cluster-tree topology where sensor nodes can switch off their transceivers and go into a sleep state to save energy. However, the IEEE 802.15.4 cluster-tree topology may not be able to provide sufficient bandwidth for the increased traffic load and the additional information may not be delivered successfully. The common drawback of the existing approaches is that they do not address the poor bandwidth utilization problem in IEEE 802.15.4 cluster-tree networks, so it is difficult to increase the network performance. Therefore, to solve this problem in this paper we study a relay transmission protocol based on the standard protocol in the IEEE 802.15.4 MAC. In the proposed scheme, the coordinators can relay data frames to their parent devices or their children devices without contention and can provide bandwidth for the increased traffic load or the number of devices. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the reliability, the end-to-end delay, and the energy consumption. PMID:27355952

  18. Time and Energy Efficient Relay Transmission for Multi-Hop Wireless Sensor Networks.

    Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

    2016-01-01

    The IEEE 802.15.4 standard is widely recognized as one of the most successful enabling technologies for short range low rate wireless communications and it is used in IoT applications. It covers all the details related to the MAC and PHY layers of the IoT protocol stack. Due to the nature of IoT, the wireless sensor networks are autonomously self-organized networks without infrastructure support. One of the issues in IoT is the network scalability. To address this issue, it is necessary to support the multi-hop topology. The IEEE 802.15.4 network can support a star, peer-to-peer, or cluster-tree topology. One of the IEEE 802.15.4 topologies suited for the high predictability of performance guarantees and energy efficient behavior is a cluster-tree topology where sensor nodes can switch off their transceivers and go into a sleep state to save energy. However, the IEEE 802.15.4 cluster-tree topology may not be able to provide sufficient bandwidth for the increased traffic load and the additional information may not be delivered successfully. The common drawback of the existing approaches is that they do not address the poor bandwidth utilization problem in IEEE 802.15.4 cluster-tree networks, so it is difficult to increase the network performance. Therefore, to solve this problem in this paper we study a relay transmission protocol based on the standard protocol in the IEEE 802.15.4 MAC. In the proposed scheme, the coordinators can relay data frames to their parent devices or their children devices without contention and can provide bandwidth for the increased traffic load or the number of devices. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the reliability, the end-to-end delay, and the energy consumption. PMID:27355952

  19. The Effect of Curriculum for Developing Efficient Studying Skills on Academic Achievements and Studying Skills of Learners

    Demir, Semra; Kilinc, Mehmet; Dogan, Ali

    2012-01-01

    Purpose of this study is to examine the effect of "Development of Efficient Studying Skills Curriculum" on academic achievements and studying skills of 7th grade primary school students. In this study, pre-test post-test from experiment models and semi-experimental model with control group were preferred. The reason for the preference is…

  20. Assessment of the achieved savings from induction motors energy efficiency labeling in Brazil

    Highlights: • We have modeled the influence of the increase of efficiency of motors. • The amount of saved energy is estimated. • The work deals with the “measurement” of a non-consumed energy. • The influence of the motor useful life is taken into account. • The influence of efficiency decrease along the motor life is also taken into account. - Abstract: Since 1995 Brazil has been applying its labeling program to increase the efficiency of application of many household appliances and equipment. From 2003 on inductions motors have also been receiving the PROCEL prize, which helped push motors efficiency over than those limits established by the labeling program. Therefore, this work presents the development of a model to estimate the amount of savings obtained with the usage of the PROCEL endorsement labels in standard and in energy efficient motors. The estimated peak demand reduction is also inferred. The developed model makes the usage of sales information and of a discard function to estimate the Brazilian motor stock. Approaches such as the use of efficiency loading and efficiency aging factors are employed to estimate motors consumption

  1. Use of FACTS for enhanced flexibility and efficiency in power transmission and distribution grids

    Grunbaum, Rolf; Wahlberg, Conny; Sannino, Ambra

    2010-09-15

    The paper shows how the use of FACTS increases flexibility in power transmission and distribution, improving capacity of transmission corridors to integrate renewable power production. Examples included are 69 kV directly connected SVCs for grid stabilization in conjunction with a high degree of wind power penetration; series compensation to evacuate power from the largest wind power installation in USA; SVC to increase the reliability and reduce congestion over a heavily loaded power corridor; thyristor controlled series compensation to increase the dynamic stability and power transmission capability of a power inter-connector. Finally, some applications of Dynamic energy storage are highlighted.

  2. Simple and efficient way of speeding up transmission calculations with k-point sampling

    Jesper Toft Falkenberg

    2015-07-01

    Full Text Available The transmissions as functions of energy are central for electron or phonon transport in the Landauer transport picture. We suggest a simple and computationally “cheap” post-processing scheme to interpolate transmission functions over k-points to get smooth well-converged average transmission functions. This is relevant for data obtained using typical “expensive” first principles calculations where the leads/electrodes are described by periodic boundary conditions. We show examples of transport in graphene structures where a speed-up of an order of magnitude is easily obtained.

  3. Simple and efficient way of speeding up transmission calculations with $k$-point sampling

    Falkenberg, Jesper Toft

    2015-01-01

    The transmissions as functions of energy are central for electron or phonon transport in the Landauer transport picture. We suggest a simple and computationally "cheap" post-processing scheme to interpolate transmission functions over $k$-points to get smooth well-converged average transmission functions. This is relevant for data obtained using typical "expensive" first principles calculations where the leads/electrodes are described by periodic boundary conditions. We show examples of transport in graphene structures where a speed-up of an order of magnitude is easily obtained.

  4. Prospects for Prudential Policy: Toward Achieving an Efficient and Stable Banking System

    Oda, Nobuyuki; Shimizu, Tokiko

    2000-01-01

    This paper examines how public intervention (prudential policy) in the banking area should be pursued and aims at providing points for discussion in considering what kind of system should be established to promote both the efficiency and stability of banking functions. The basic thrust of the paper is that it is effective to utilize market mechanisms to improve the efficiency of banking functions and that public intervention is justified in coping with various market failures if optimality is...

  5. O&M Best Practices - A Guide to Achieving Operational Efficiency (Release 2.0)

    Sullivan, Gregory P.; Pugh, Ray; Melendez, Aldo P.; Hunt, W. D.

    2004-07-31

    This guide, sponsored by DOE's Federal Energy Management Program, highlights operations and maintenance (O&M) programs targeting energy efficiency that are estimated to save 5% to 20% on energy bills without a significant capital investment. The purpose of this guide is to provide the federal O&M energy manager and practitioner with useful information about O&M management, technologies, energy efficiency and cost-reduction approaches.

  6. A Thorough and Efficient Education: School Funding, Student Achievement and Productivity

    Ahlgrim, Richard W.

    2010-01-01

    Many school districts are facing stagnant or reduced funding (input) concurrent with demands for improved student achievement (output). In other words, there is pressure for all schools, even those schools with student populations of low socioeconomic status, to improve academic results (accountability for output) without a directly proportionate…

  7. A Cross-Layer Wireless Sensor Network Energy-Efficient Communication Protocol for Real-Time Monitoring of the Long-Distance Electric Transmission Lines

    Jun Yu

    2015-01-01

    Full Text Available Optimization of energy consumption in Wireless Sensor Network (WSN nodes has become a critical link that constrains the engineering application of the smart grid due to the fact that the smart grid is characterized by long-distance transmission in a special environment. The paper proposes a linear hierarchical network topological structure specific to WSN energy conservation in environmental monitoring of the long-distance electric transmission lines in the smart grid. Based on the topological structural characteristics and optimization of network layers, the paper also proposes a Topological Structure be Layered Configurations (TSLC routing algorithm to improve the quality of WSN data transmission performance. Coprocessing of the network layer and the media access control (MAC layer is achieved by using the cross-layer design method, accessing the status for the nodes in the network layer and obtaining the status of the network nodes of the MAC layer. It efficiently saves the energy of the whole network, improves the quality of the network service performance, and prolongs the life cycle of the network.

  8. Analysis of Electro-Electro Transmission Efficiency of SAW IDTs System by Six-Port Equivalent Circuit Model

    CHENMing; TANGTiantong; CHENGuangde; ZHANGPenghui

    2003-01-01

    Analysis of electro - electro power transmission efficiency of SAW IDTs (Surface-acoustic-wave Interdigital transducers) system is studied, which is based on the newly developed simple six-port equivalent circuit model for SAW IDTs. The application of this method to the SAW IDTs with 80 fingers system on Y-Z LiNbO3 for acousto-optical interaction is also investigated, and it shows that the calculated result is in agreement with experimental one.

  9. Localization, Concentration, and Transmission Efficiency of Banana bunchy top virus in Four Asexual Lineages of Pentalonia aphids

    Alberto Bressan; Shizu Watanabe; April M. Greenwell

    2013-01-01

    Banana bunchy top virus (BBTV) is the most destructive pathogenic virus of banana plants worldwide. The virus is transmitted in a circulative non-propagative manner by the banana aphid, Pentalonia nigronervosa Coquerel. In this work, we examined the localization, accumulation, and transmission efficiency of BBTV in four laboratory-established lineages of Pentalonia aphids derived from four different host plants: taro (Colocasia esculenta), heliconia (Heliconia spp.), red ginger (Alpinia purpu...

  10. Design of high-efficiency broad-bandwidth pulse compression device based on composite transmission grating with high damage threshold

    Chen, Xinrong; Li, Chaoming; Liu, Linyue; Li, Lin; Wu, Jianhong; Chang, Zenghu

    2014-11-01

    A novel pulse compression device has been developed for femto-second Ti: sapphire laser at 800nm center wavelength with 700nm~900nm bandwidth. This new kind of composite pulse compression device consists of two fused silica transmission gratings with 1250lp/mm and 3300lp/mm respectively and these two fused silica transmission gratings are located in two optical surfaces of the same fused silica plate. Owing to use anti-reflection transmission gratings with high space frequency (3300lp/mm), it can avoid the wave-front distort derived from coating antireflection film on one surface of the fused silica plate. Being made of fused silica, this new composite pulse compression device will be expected to have high laser damage threshold. The calculation results show that: the -1st order diffraction efficiency of 1250lp/mm grating is over 87% within the 700nm and 900nm broad-bandwidth for rectangular groove and TE polarization state. And the average diffraction efficiency within the 700nm and 900nm broad-bandwidth is more than 92%. At 800nm, the -1st transmitted order diffraction efficiency is great to 96% while the transmittance of 3300lp/mm grating is up to 99.9%.

  11. Achieving energy efficiency in LTE with joint D2D communications and green networking techniques

    Yaacoub, Elias E.

    2013-07-01

    In this paper, the joint operation of cooperative device-to-device (D2D) communications and green cellular communications is investigated. An efficient approach for grouping mobile terminals (MTs) into cooperative clusters is described. In each cluster, MTs cooperate via D2D communications to share content of common interest. Furthermore, an energy-efficient technique for putting BSs in sleep mode in an LTE cellular network is presented. Finally, both methods are combined in order to ensure green communications for both the users\\' MTs and the operator\\'s BSs. The studied methods are investigated in the framework of OFDMA-based state-of-the-art LTE cellular networks, while taking into account intercell interference and resource allocation. © 2013 IEEE.

  12. Doping in the Mixed Layer to Achieve High Brightness and Efficiency Organic Light Emitting Devices

    高文宝; 杨开霞; 刘宏宇; 冯晶; 刘式墉

    2002-01-01

    Doping in the mixed layer was introduced to fabricate high brightness and high efficiency organic light emitting devices. In these devices, a copper phthalocyanine (CuPc) film acts as the buffer layer, a naphthylphenybiphenyl amine (NPB) film as the hole transport layer and a tris(8-hydroxyquinolinolate)aluminium (Alq3) film as the electron transport layer. The luminescent layer consists of the mixture of NPB, Alq3 (to be called the mixed layer), and an emitting dopant 5,6,11,12-petraphenylnaphthacene (rubrene), where the concentration of NPB declined and the concentration of Alq3 was increased gradually in the deposition process. Adopting this doping mixed layer, the device exhibits the maximum emission of 49300cd/m2 at 35 V and the maximum efficiency of 7.96cd/A at 10.5 V, which have been improved by two times in comparison with conventional doped devices. We attribute this improvement to the effective confinement of carriers in the mixed layer, which leads to the increase of the recombination efficiency of carriers.

  13. TRANSMISSION MOMENTARY EFFICIENCY BASED ON THE D'ALEMBERT-LAGRANGE EQUATION FOR INVOLUTES GEARS

    Liang Yi; Lai Changying

    2004-01-01

    The D'Alembert-Lagrange equation is introduced and used to derive the formulas of momentary efficiency for external gearing of standard involutes spur gears.The gearings with correct and increased center distance are discussed.The momentary efficiency formula is calculated and analyzed using software Matlab.The derived formula of momentary efficiency is also compared with the traditional formula.

  14. Reuse and recovery of raw materials: Towards the achievement of a resource-efficient society

    Resource efficiency plays a key role in the transition from a linear to a circular economy system. During the last few decades a rapid growth in the number of materials used across complex products has occurred. Given the high economic importance of critical raw materials combined with relatively high supply risk, securing reliable and undistorted access of certain raw materials is of growing concern across the globe. Development of eco-innovative approaches devoted to closing the loop of resources is strongly needed, allowing the connection between production cycles and their territory.

  15. Achieving efficiency in Africa: What are the priorities, the best practices and the policy measures?

    Fall, Latsoucabe

    2010-09-15

    Energy Efficiency (EE) improvements offer huge opportunities for Africa to meet growing energy needs, secure a more sustainable energy supply and demand, improve business productivity, preserve local environment and mitigate GHG emissions. The paper focuses on the ways and means to overcome the related challenges in order to reap the benefits of such improvements. It also identifies the priorities for Africa and provides responses on how to establish and implement effective policy-measures to enhance EE in African countries. Subsequently, it delivers key recommendations to help improve EE policies and practices and to implement national and regional measures of EE improvements.

  16. Measurement of the efficiency of gold transmission gratings in the 100 to 5000 eV photon energy range

    Three x-ray spectrometers, each with a transmission grating dispersion element, are routinely used at the Z soft x-ray facility to measure the spectrum and temporal history of the absolute soft x-ray power emitted from z-pinch and hohlraum radiation sources. Our goal is to make these measurements within an accuracy of ±10%. We periodically characterize the efficiency of the gratings used in the spectrometers by using an electron-impact soft x-ray source, a monochromator, grazing-incidence mirrors, thin filters, and an x-ray charge-coupled device (CCD) detector. We measure the transmission efficiency of the gratings at many photon energies for several grating orders. For each grating, we calculate efficiency as a function of photon energy using published optical constants of gold and multiple-slit Fraunhofer diffraction theory and fit the calculation to the measurements using the physical parameters of the grating as variables. This article describes the measurement apparatus and calibration techniques, discusses the grating efficiency calculation and fitting procedure, and presents recent results

  17. Metering Best Practices, A Guide to Achieving Utility Resource Efficiency, Release 2.0

    Sullivan, Greg; Hunt, W. D.; Pugh, Ray; Sandusky, William F.; Koehler, Theresa M.; Boyd, Brian K.

    2011-08-31

    This release is an update and expansion of the information provided in Release 1.0 of the Metering Best Practice Guide that was issued in October 2007. This release, as was the previous release, was developed under the direction of the U.S. Department of Energy's Federal Energy Management Program (FEMP). The mission of FEMP is to facilitate the Federal Government's implementation of sound cost-effective energy management and investment practices to enhance the nation's energy security and environmental stewardship. Each of these activities is directly related to achieving requirements set forth in the Energy Policy Acts of 1992 and 2005, the Energy Independence and Security Act (EISA) of 2007, and the goals that have been established in Executive Orders 13423 and 13514 - and also those practices that are inherent in sound management of Federal financial and personnel resources.

  18. AUDIT FUNCTION ROLE IN ACHIEVING AN EFFICIENT CORPORATE GOVERNANCE – CONCEPTUAL MODEL PROPOSAL

    Melinda Timea Fülöp

    2013-12-01

    Full Text Available Nowadays corporate governance plays an important role in decisions making processes, which represents a relatively new approach for both Romanian scientific studies and practice. As a consequence we consider the increased attention given to corporate governance to be crucial, especially addressing the role of the audit function and the importance of the corporate governance code. Audit function is of particular practical importance in corporate governance, therefore we decided meticulously to consider it, and especially to develop a conceptual framework for its role in support of an effective corporate governance. We consider that there are two levels and seven key elements utilized in order to achieve an effective corporate governance. In conclusion, audit function as a whole, with an active role in improving corporate governance, should perform correlated in terms of its components: internal audit, external audit and audit committees.

  19. Achieving Internet-based efficiencies in a rural IDS: a case study.

    Bacus, R; Zunke, R

    2001-09-01

    After suffering payment cuts resulting from the Balanced Budget Act of 1997, Colorado-Fayette Medical Center (CFMC), a not-for-profit, rural integrated delivery system in Texas, wanted to reduce costs by gaining systemwide Internet access for its internal information system at a reasonable price. An application service provider affiliated with the Texas Hospital Association, helped CFMC achieve its goals for the project by performing a needs assessment, installing a wide-area network (WAN) with Internet access, and training staff. The new WAN enabled CFMC to improve its Web presence, allow radiologic image viewing at all sites, negotiate more favorable prices from vendors, implement electronic communication for staff members, and take advantage of on-line education opportunities. CFMC has found that the monthly fee paid to THN is offset by savings on long-distance calls, Internet service provider fees, and marketing and advertising costs. PMID:11552587

  20. Achievements and suggestions of heat metering and energy efficiency retrofit for existing residential buildings in northern heating regions of China

    In order to promote energy efficiency and emission reduction, the importance of improving building energy efficiency received sufficient attention from Chinese Government. The heat metering and energy efficiency retrofit for existing residential buildings of 0.15 billion m2 in northern heating regions of China was initiated in 2007 and completed successfully at the end of 2010. This article introduced the background and outline of the retrofit project during the period of 11th five-year plan. Numerous achievements that received by retrofit such as environmental protection effect, improvement of indoor environment, improvement of heating system, investment guidance effect, promotion of relevant industries and increasing chances of employment were concluded. Valuable experience that acquired from the retrofit project during the period of 11th five-year plan was also summarized in this article. By analyzing the main problems emerged in the past, pertinent suggestions were put forward to promote a larger scale and more efficient retrofit project in the period of 12th five-year plan. - Highlights: →Successful implementation of a retrofit project in China is introduced. → Significance of the project contributing to emission reduction is analyzed. →Achievements are summarized and future suggestions are put forward.

  1. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: II. Solutions and applications

    Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha

    2014-10-01

    In a companion manuscript (Frolov et al 2014 New J. Phys. 16 art. no.) , we developed a novel optimization method for the placement, sizing, and operation of flexible alternating current transmission system (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide series compensation (SC) via modification of line inductance. In this sequel manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (˜2700 nodes and ˜3300 lines). The results from the 30-bus network are used to study the general properties of the solutions, including nonlocality and sparsity. The Polish grid is used to demonstrate the computational efficiency of the heuristics that leverage sequential linearization of power flow constraints, and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, we can use the algorithm to solve a Polish transmission grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (i) uniform load growth, (ii) multiple overloaded configurations, and (iii) sequential generator retirements.

  2. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: II. Solutions and applications

    In a companion manuscript (Frolov et al 2014 New J. Phys. 16 art. no.) , we developed a novel optimization method for the placement, sizing, and operation of flexible alternating current transmission system (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide series compensation (SC) via modification of line inductance. In this sequel manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (∼2700 nodes and ∼3300 lines). The results from the 30-bus network are used to study the general properties of the solutions, including nonlocality and sparsity. The Polish grid is used to demonstrate the computational efficiency of the heuristics that leverage sequential linearization of power flow constraints, and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, we can use the algorithm to solve a Polish transmission grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (i) uniform load growth, (ii) multiple overloaded configurations, and (iii) sequential generator retirements. (paper)

  3. Role for the Plasmodium sporozoite-specific transmembrane protein S6 in parasite motility and efficient malaria transmission.

    Steinbuechel, Marion; Matuschewski, Kai

    2009-02-01

    Malaria transmission occurs by intradermal deposition of Plasmodium sporozoites during the infectious bite of a female Anopheles mosquito. After formation in midgut-associated oocysts sporozoites actively enter mosquito salivary glands and subsequently invade host hepatocytes where they transform into clinically silent liver stages. To date, two sporozoite-specific transmembrane proteins have been identified that perform vital functions in natural malaria transmission. The sporozoite invasin TRAP drives sporozoite motility and target cell entry whereas the adhesin MAEBL mediates sporozoite recognition of and attachment to salivary glands. Here, we demonstrate that the sporozoite-specific transmembrane protein S6 is required for efficient malaria transmission to the vertebrate host. Targeted deletion of S6 results in severe impairment of sporozoite gliding motility and invasion of mosquito salivary glands. During sporozoite maturation S6 expression is tightly regulated by transcriptional and translational control. We propose that S6 functions together with TRAP/MIC2 family invasins to direct fast, efficient and specific cell entry and, ultimately, life cycle progression of the malaria sporozoite. PMID:19016774

  4. Operations & Maintenance Best Practices - A Guide to Achieving Operational Efficiency (Release 3)

    Sullivan, Greg; Pugh, Ray; Melendez, Aldo P.; Hunt, W. D.

    2010-08-04

    This guide highlights operations and maintenance programs targeting energy and water efficiency that are estimated to save 5% to 20% on energy bills without a significant capital investment. The purpose of this guide is to provide you, the Operations and Maintenance (O&M)/Energy manager and practitioner, with useful information about O&M management, technologies, energy and water efficiency, and cost-reduction approaches. To make this guide useful and to reflect your needs and concerns, the authors met with O&M and Energy managers via Federal Energy Management Program (FEMP) workshops. In addition, the authors conducted extensive literature searches and contacted numerous vendors and industry experts. The information and case studies that appear in this guide resulted from these activities. It needs to be stated at the outset that this guide is designed to provide information on effective O&M as it applies to systems and equipment typically found at Federal facilities. This guide is not designed to provide the reader with step-by-step procedures for performing O&M on any specific piece of equipment. Rather, this guide first directs the user to the manufacturer's specifications and recommendations. In no way should the recommendations in this guide be used in place of manufacturer's recommendations. The recommendations in this guide are designed to supplement those of the manufacturer, or, as is all too often the case, provide guidance for systems and equipment for which all technical documentation has been lost. As a rule, this guide will first defer to the manufacturer's recommendations on equipment operation and maintenance.

  5. Reduction of PAPR and Efficient detection ordering scheme for MIMO Transmission Systems Using Power Control

    V.Sreevani

    2015-12-01

    Full Text Available The technical challenges for communication engineers is the development of best performance wireless networks with negligible amount of distortions. We have to consider multipath propagation attenuation and radio spectrum inefficiency. Now a days, In MIMO (Multi Input Multi Output systems there is a huge demand for the networks with the high transmission rates and better quality of service which are having low PAPR ratio. Instead of OFDMA, filter banks are used in massive MIMO to reduce the complexity. But they are error prone to noise. This base paper discusses about PAPR reduction in MIMO systems using different precoding based OFDM systems. Mainly, minimization of multi-antenna systems by controlling the transmission power and reduction of PAPR using ZC (Zadoff-Chu matrix transform.

  6. Efficiency Evaluation of Lightning Fault Inspection in 66kV Transmission Line

    Narita, Tomomi; Yamaguchi, Setsuo

    Transmission line must be immediately inspected when it was struck by lightning. It is necessary to find and change the damaged part promptly in case the damage is serious. Such case, however, is actually hardly seen due to the fact that the lightning protection system is well designed recently. Therefore, it is important to compare the data of past lightnings and of the transmission line, and make criteria for deciding more precisely in which case the actual inspection should be carried out. The criteria would be as follows: (1) Insulator voltage exceeds critical voltage. (2) Arc current and arc duration exceed characteristic of insulator destruction. (3) Accident phase exceeds 3 line ground fault. (4) Tower foot resistance is up to 10ohm or more. (5) Lightning current is positive characteristic. By using this criteria, the number of lightning fault inspection was reduced by 34%.

  7. Call Transmission Efficiency in Native and Invasive Anurans: Competing Hypotheses of Divergence in Acoustic Signals

    Llusia, Diego; Gómez, Miguel; Penna, Mario; Márquez, Rafael

    2013-01-01

    Invasive species are a leading cause of the current biodiversity decline, and hence examining the major traits favouring invasion is a key and long-standing goal of invasion biology. Despite the prominent role of the advertisement calls in sexual selection and reproduction, very little attention has been paid to the features of acoustic communication of invasive species in nonindigenous habitats and their potential impacts on native species. Here we compare for the first time the transmission...

  8. The use of ECDIS equipment to achieve an optimum value for energy efficiency operation index

    Acomi, N.; Acomi, O. C.; Stanca, C.

    2015-11-01

    To reduce air pollution produced by ships, the International Maritime Organization has developed a set of technical, operational and management measures. The subject of our research addresses the operational measures for minimizing CO2 air emissions and the way how the emission value could be influenced by external factors regardless of ship-owners’ will. This study aims to analyse the air emissions for a loaded voyage leg performed by an oil tanker. The formula that allows us to calculate the predicted Energy Efficiency Operational Index involves the estimation of distance and fuel consumption, while the quantity of cargo is known. The electronic chart display and information system, ECDIS Simulation Software, will be used for adjusting the passage plan in real time, given the predicted severe environmental conditions. The distance will be determined using ECDIS, while the prediction of the fuel consumption will consider the sea trial and the vessel experience records. That way it will be possible to compare the estimated EEOI value in the case of great circle navigation in adverse weather condition with the estimated EEOI value for weather navigation.

  9. Oxidation of steels in liquid lead bismuth: Oxygen control to achieve efficient corrosion protection

    Martinelli, Laure, E-mail: laure.martinelli@cea.f [CEA, DEN, DPC, SCCME, Laboratoire d' Etude de la Corrosion Non Aqueuse, F-91191 Gif-sur-Yvette (France); Jean-Louis, Courouau; Fanny, Balbaud-Celerier [CEA, DEN, DPC, SCCME, Laboratoire d' Etude de la Corrosion Non Aqueuse, F-91191 Gif-sur-Yvette (France)

    2011-05-15

    Hybrid systems dedicated to waste transmutation are constituted of an accelerator generating a high energy proton flux, a spallation target on which the accelerated proton beam impinges to produce neutrons and a subcritical core. The Pb-Bi eutectic liquid alloy is considered as spallation target material due to its suitable nuclear and physical properties. However, liquid metals can be corrosive towards containment materials (austenitic and Fe9Cr alloys). In the case of liquid lead bismuth alloy, one of the protection means considered against the dissolution of the steels is the in situ protection by the formation of an oxide layer at the steels' surface. However, in order to ensure the efficient protection of the steels by an oxide layer, the control and the monitoring of the oxygen content in the Pb-Bi alloy is a major issue. The paper recalls, first, the oxygen chemistry in a lead alloy system, in order to propose the oxygen operating window that complies with both the contamination by lead oxide of the coolant and the corrosion control by the promotion of an oxide film on the structure. Results of tests performed in stagnant lead bismuth at high oxygen concentrations are also presented showing the effect of various operating parameters on the oxidation kinetics and on the nature of the oxide layer. An oxidation mechanism and model are also proposed and compared with experimental data.

  10. ITC SOLUTIONS TO ACHIEVE PERFORMANCE AND EFFICIENCY OF HEALTH SERVICES: ONLINE VIRTUAL CLINIC

    Adina BĂLAN

    2010-01-01

    Full Text Available The digital era modified the way people work, how the information and the informational resources are defined and organized. The organization which holds, uses and correctly reproduces the piece of information, the knowledge, the intellectual capital, becomes a leader in the proper field of activity. Following the actual tendencies in the digital era connected to the exchange of professional information, I can say that the exchange and sharing of digital information in a global multitude of interconnected computers are essential instruments that can contribute to the development and consolidation of the intellectual potential of the organization. This is why, the access of the individuals to information is an actual requirement of the development of the Romanian society in the context of globalization and world implication o contemporary processes and phenomena. The Digital integration eliminates the barriers that traditionally suppress the circuit of the medical information, lets the goods and services circulate to and from Romania by promoting efficiency as final purpose. Performance is needed in the health system, the transformation of the system of medical services by bringing the benefits of the medical science and technology to all individuals from every community. In order to accomplish these expectations it is needed that all the components that form the health system look at it as a whole and subscribe to modern solutions for improvement so that the quality of health should raise to an unprecedented level. Even if health systems differ from country to country from the organizational and financial point of view, they face the same challenges and problems, respectively the supply of medical care of better quality and keeping under control the health expenses. The use of information and communication technology in the field of medical assistance in order to stock, share, transmit and analyze clinical data and knowledge is more necessary

  11. Energy-Efficient Transmissions for Remote Wireless Sensor Networks: An Integrated HAP/Satellite Architecture for Emergency Scenarios

    Feihong Dong

    2015-09-01

    Full Text Available A typical application scenario of remote wireless sensor networks (WSNs is identified as an emergency scenario. One of the greatest design challenges for communications in emergency scenarios is energy-efficient transmission, due to scarce electrical energy in large-scale natural and man-made disasters. Integrated high altitude platform (HAP/satellite networks are expected to optimally meet emergency communication requirements. In this paper, a novel integrated HAP/satellite (IHS architecture is proposed, and three segments of the architecture are investigated in detail. The concept of link-state advertisement (LSA is designed in a slow flat Rician fading channel. The LSA is received and processed by the terminal to estimate the link state information, which can significantly reduce the energy consumption at the terminal end. Furthermore, the transmission power requirements of the HAPs and terminals are derived using the gradient descent and differential equation methods. The energy consumption is modeled at both the source and system level. An innovative and adaptive algorithm is given for the energy-efficient path selection. The simulation results validate the effectiveness of the proposed adaptive algorithm. It is shown that the proposed adaptive algorithm can significantly improve energy efficiency when combined with the LSA and the energy consumption estimation.

  12. Energy-Efficient Transmissions for Remote Wireless Sensor Networks: An Integrated HAP/Satellite Architecture for Emergency Scenarios.

    Dong, Feihong; Li, Hongjun; Gong, Xiangwu; Liu, Quan; Wang, Jingchao

    2015-01-01

    A typical application scenario of remote wireless sensor networks (WSNs) is identified as an emergency scenario. One of the greatest design challenges for communications in emergency scenarios is energy-efficient transmission, due to scarce electrical energy in large-scale natural and man-made disasters. Integrated high altitude platform (HAP)/satellite networks are expected to optimally meet emergency communication requirements. In this paper, a novel integrated HAP/satellite (IHS) architecture is proposed, and three segments of the architecture are investigated in detail. The concept of link-state advertisement (LSA) is designed in a slow flat Rician fading channel. The LSA is received and processed by the terminal to estimate the link state information, which can significantly reduce the energy consumption at the terminal end. Furthermore, the transmission power requirements of the HAPs and terminals are derived using the gradient descent and differential equation methods. The energy consumption is modeled at both the source and system level. An innovative and adaptive algorithm is given for the energy-efficient path selection. The simulation results validate the effectiveness of the proposed adaptive algorithm. It is shown that the proposed adaptive algorithm can significantly improve energy efficiency when combined with the LSA and the energy consumption estimation. PMID:26404292

  13. Efficiency of helicon isolator use in antenna transmission lines on meter and decameter waves

    Vountesmery, Vladimir S.

    1997-01-01

    The helicon isolators on high frequencies are the analogues of microwave ferrite isolators and can be used for decoupling in radiohardware and measurement stations. It is especially efficient to use helicon isolators in radiocommunication systems.

  14. A generalized transmission method for gamma-efficiency determinations in soil samples

    In this paper, a generalization of the γ-ray transmission method which is useful for measurements on soil samples, for example, is presented. The correction factor, f, is given, which is a function of the apparent density of the soil and the γ-ray energy. With this method, the need for individual determinations of f, for each energy and apparent soil density is avoided. Although the method has been developed for soils, the general philosophy can be applied to other sample matrices, such as water or vegetables for example. (author)

  15. Efficient 2.45 GHz Rectenna Design with high Harmonic Rejection for Wireless Power Transmission

    Zied Harouni; Lotfi Osman; Ali Gharsallah

    2010-01-01

    The purpose of this work is to propose an efficient microstrip rectenna operating on ISM band with high harmonic rejection. The receiving antenna with proximity coupled feeding line implemented in a multilayer substrate. The rectenna with integrated circular sector antenna can eliminate the need for an low pass filter (LPF) placed between the antenna and the diode as well as produce higher output power, with maximum conversion efficiency of 74% using a 1300 load resistor at a power density of...

  16. Efficient time-domain simulation of nonlinear, state-space, transmission-line models of the cochlea (L).

    Pan, Shuokai; Elliott, Stephen J; Teal, Paul D; Lineton, Ben

    2015-06-01

    Nonlinear models of the cochlea are best implemented in the time domain, but their computational demands usually limit the duration of the simulations that can reasonably be performed. This letter presents a modified state space method and its application to an example nonlinear one-dimensional transmission-line cochlear model. The sparsity pattern of the individual matrices for this alternative formulation allows the use of significantly faster numerical algorithms. Combined with a more efficient implementation of the saturating nonlinearity, the computational speed of this modified state space method is more than 40 times faster than that of the original formulation. PMID:26093443

  17. Productivity and efficiency of US gas transmission companies: A European regulatory perspective

    On both sides of the Atlantic, the regulation of gas transmission networks has undergone major changes since the early 1990s. Whereas in the US, the long-standing regime of cost-plus regulation was complemented by increasing pipe-to-pipe competition, most European countries moved towards incentive regulation complemented by market integration. We study the productivity development of a panel of US interstate companies using data envelopment analysis and Malmquist productivity indices. Results are presented for changes in productivity, as well as for several convergence tests. The results indicate that taking productivity and convergence as performance indicators, regulation has been rather successful, in particular during a period where overall demand was flat. However, we argue that a benchmarking-based regulation might have brought about stronger convergence. Lessons for European regulators are twofold. First, the US analysis shows that benchmarking of European transmission operators would be possible if data were available. Second, our results suggest that, in the long-run, market integration and competition are alternatives to the current European model

  18. An energy-efficient transmission scheme for real-time data in wireless sensor networks.

    Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

    2015-01-01

    The Internet of things (IoT) is a novel paradigm where all things or objects in daily life can communicate with other devices and provide services over the Internet. Things or objects need identifying, sensing, networking and processing capabilities to make the IoT paradigm a reality. The IEEE 802.15.4 standard is one of the main communication protocols proposed for the IoT. The IEEE 802.15.4 standard provides the guaranteed time slot (GTS) mechanism that supports the quality of service (QoS) for the real-time data transmission. In spite of some QoS features in IEEE 802.15.4 standard, the problem of end-to-end delay still remains. In order to solve this problem, we propose a cooperative medium access scheme (MAC) protocol for real-time data transmission. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the network performance. PMID:26007722

  19. An Energy-Efficient Transmission Scheme for Real-Time Data in Wireless Sensor Networks

    Jin-Woo Kim

    2015-05-01

    Full Text Available The Internet of things (IoT is a novel paradigm where all things or objects in daily life can communicate with other devices and provide services over the Internet. Things or objects need identifying, sensing, networking and processing capabilities to make the IoT paradigm a reality. The IEEE 802.15.4 standard is one of the main communication protocols proposed for the IoT. The IEEE 802.15.4 standard provides the guaranteed time slot (GTS mechanism that supports the quality of service (QoS for the real-time data transmission. In spite of some QoS features in IEEE 802.15.4 standard, the problem of end-to-end delay still remains. In order to solve this problem, we propose a cooperative medium access scheme (MAC protocol for real-time data transmission. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the network performance.

  20. Benefits of Hybrid-Electric Propulsion to Achieve 4x Increase in Cruise Efficiency for a VTOL Aircraft

    Fredericks, William J.; Moore, Mark D.; Busan, Ronald C.

    2013-01-01

    Electric propulsion enables radical new vehicle concepts, particularly for Vertical Takeoff and Landing (VTOL) aircraft because of their significant mismatch between takeoff and cruise power conditions. However, electric propulsion does not merely provide the ability to normalize the power required across the phases of flight, in the way that automobiles also use hybrid electric technologies. The ability to distribute the thrust across the airframe, without mechanical complexity and with a scale-free propulsion system, is a new degree of freedom for aircraft designers. Electric propulsion is scale-free in terms of being able to achieve highly similar levels of motor power to weight and efficiency across a dramatic scaling range. Applying these combined principles of electric propulsion across a VTOL aircraft permits an improvement in aerodynamic efficiency that is approximately four times the state of the art of conventional helicopter configurations. Helicopters typically achieve a lift to drag ratio (L/D) of between 4 and 5, while the VTOL aircraft designed and developed in this research were designed to achieve an L/D of approximately 20. Fundamentally, the ability to eliminate the problem of advancing and retreating rotor blades is shown, without resorting to unacceptable prior solutions such as tail-sitters. This combination of concept and technology also enables a four times increase in range and endurance while maintaining the full VTOL and hover capability provided by a helicopter. Also important is the ability to achieve low disc-loading for low ground impingement velocities, low noise and hover power minimization (thus reducing energy consumption in VTOL phases). This combination of low noise and electric propulsion (i.e. zero emissions) will produce a much more community-friendly class of vehicles. This research provides a review of the concept brainstorming, configuration aerodynamic and mission analysis, as well as subscale prototype construction and

  1. Efficient Algorithm for Locating and Sizing Series Compensation Devices in Large Transmission Grids: Model Implementation (PART 1)

    Frolov, Vladimir [Moscow Inst. of Physics and Technology (MIPT), Moscow (Russian Federation); Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chertkov, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-14

    We explore optimization methods for planning the placement, sizing and operations of Flexible Alternating Current Transmission System (FACTS) devices installed to relieve transmission grid congestion. We limit our selection of FACTS devices to Series Compensation (SC) devices that can be represented by modification of the inductance of transmission lines. Our master optimization problem minimizes the l1 norm of the inductance modification subject to the usual line thermal-limit constraints. We develop heuristics that reduce this non-convex optimization to a succession of Linear Programs (LP) which are accelerated further using cutting plane methods. The algorithm solves an instance of the MatPower Polish Grid model (3299 lines and 2746 nodes) in 40 seconds per iteration on a standard laptop—a speed up that allows the sizing and placement of a family of SC devices to correct a large set of anticipated congestions. We observe that our algorithm finds feasible solutions that are always sparse, i.e., SC devices are placed on only a few lines. In a companion manuscript, we demonstrate our approach on realistically-sized networks that suffer congestion from a range of causes including generator retirement. In this manuscript, we focus on the development of our approach, investigate its structure on a small test system subject to congestion from uniform load growth, and demonstrate computational efficiency on a realistically-sized network.

  2. Efficient Algorithm for Locating and Sizing Series Compensation Devices in Large Transmission Grids: Solutions and Applications (PART II)

    Frolov, Vladimir [Moscow Inst. of Physics and Technology (MIPT), Moscow (Russian Federation); Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chertkov, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-14

    In a companion manuscript, we developed a novel optimization method for placement, sizing, and operation of Flexible Alternating Current Transmission System (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide Series Compensation (SC) via modification of line inductance. In this manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (~2700 nodes and ~3300 lines). The results on the 30-bus network are used to study the general properties of the solutions including non-locality and sparsity. The Polish grid is used as a demonstration of the computational efficiency of the heuristics that leverages sequential linearization of power flow constraints and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, the algorithm is able to solve an instance of Polish grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (a) uniform load growth, (b) multiple overloaded configurations, and (c) sequential generator retirements

  3. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: I. Model implementation

    We explore optimization methods for planning the placement, sizing and operations of flexible alternating current transmission system (FACTS) devices installed to relieve transmission grid congestion. We limit our selection of FACTS devices to series compensation (SC) devices that can be represented by modification of the inductance of transmission lines. Our master optimization problem minimizes the l1 norm of the inductance modification subject to the usual line thermal-limit constraints. We develop heuristics that reduce this non-convex optimization to a succession of linear programs (LP) that are accelerated further using cutting plane methods. The algorithm solves an instance of the MatPower Polish Grid model (3299 lines and 2746 nodes) in 40 seconds per iteration on a standard laptop—a speed that allows the sizing and placement of a family of SC devices to correct a large set of anticipated congestions. We observe that our algorithm finds feasible solutions that are always sparse, i.e., SC devices are placed on only a few lines. In a companion manuscript, we demonstrate our approach on realistically sized networks that suffer congestion from a range of causes, including generator retirement. In this manuscript, we focus on the development of our approach, investigate its structure on a small test system subject to congestion from uniform load growth, and demonstrate computational efficiency on a realistically sized network. (paper)

  4. Efficient and configurable transmission protocol based on UDP in grid computing

    Jigang WANG; Guochang GU; Chunguang MA; Weidong ZHONG

    2009-01-01

    At present,mainstream data transfer protocols are not always a good match for the diverse demands of grid computing.Considering this situation,this article proposes an efficient and configurable data transfer protocol (ECUDP) for grid computing.The ECUDP is based on the standard user datagram protocol (UDP),but with a collection of optimizations that meet the challenge of providing configurability and reliability while main-taining performance that meets the communication requirements of demanding applications.Experimental results show that the ECUDP performs efficiently in various grid computing scenarios and the performance analysis model can provide a good estimation of its performance.

  5. Efficient 2.45 GHz Rectenna Design with high Harmonic Rejection for Wireless Power Transmission

    Zied Harouni

    2010-09-01

    Full Text Available The purpose of this work is to propose an efficient microstrip rectenna operating on ISM band with high harmonic rejection. The receiving antenna with proximity coupled feeding line implemented in a multilayer substrate. The rectenna with integrated circular sector antenna can eliminate the need for an low pass filter (LPF placed between the antenna and the diode as well as produce higher output power, with maximum conversion efficiency of 74% using a 1300 load resistor at a power density of 0.3 mW/cm square.

  6. Improvement The Transmission Efficiency For Wireless Packet Communication Systems Using Automatic Control for power And Time Slot Width Of Slotted Non persistent ISMA Protocol

    Saad Meshhen Hardan

    2013-01-01

    In packed communication systems which use a protocol, the protocol should perform the allocation of channels such that the transmission channel is used efficiently. Efficiency is usually measured in terms of channel throughput and the average transmission  delay. The Slotted Nonpersistent ISMA protocol is one of random access protocols used in packed communication systems. In this research a Slotted Nonpersistent ISMA protocol Model with automatic control for power and time slot is proposed. ...

  7. Efficient Frame Schedule Scheme for Real-time Video Transmission Across the Internet Using TCP

    Yonghua Xiong

    2009-05-01

    Full Text Available The great end-to-end delays are the major factor to influence the visual quality of real-time video across the Internet using TCP as transport layer protocol. In this paper, we present a video frame schedule scheme for rate adaptive real-time video transmission over TCP. The scheme schedules video frames between the application layer sender-buffer, the TCP sender-buffer and TCP receiver-buffer and can regulate automaticlly the video frame rate and play out buffer delays according to the network congestion level. The sheme requires only an extra buffer of application layer and can significantly cut down the end-to-end delays of real-time video without any modification to the network infrastructure or TCP protocol stack. The performance of the proposed solution is evaluated through extensive simulations using the NS-2 simulator.

  8. The perfect host: a mouse host embryo facilitating more efficient germ line transmission of genetically modified embryonic stem cells.

    Robert A Taft

    Full Text Available There is a continual need to improve efficiency in creating precise genetic modifications in mice using embryonic stem cells (ESCs. We describe a novel approach resulting in 100% germline transmission from competent injected ESCs. We developed an F1 mouse host embryo (Perfect Host, PH that selectively ablates its own germ cells via tissue-specific induction of diphtheria toxin. This approach allows competent microinjected ESCs to fully dominate the germline, eliminating competition for this critical niche in the developing and adult animal. This is in contrast to conventional methods, where competition from host germ cells results in offspring derived from host cells and ESCs, necessitating extensive breeding of chimeras and genotyping to identify germline. The germline transmission process is also complicated by variability in the actual number of ESCs that colonize the germline niche and the proportion that are germline competent. To validate the PH approach we used ESC lines derived from 129 F1, BALB/cByJ, and BTBR backgrounds as well as an iPS line. Resulting chimeric males produced 194 offspring, all paternally derived from the introduced stem cells, with no offspring being derived from the host genome. We further tested this approach using eleven genetically modified C57BL/6N ESC lines (International Knockout Mouse Consortium. ESC germline transmission was observed in 9/11 (82% lines using PH blastocysts, compared to 6/11 (55% when conventional host blastocysts were used. Furthermore, less than 35% (83/240 of mice born in the first litters from conventional chimeras were confirmed to be of ESC-origin. By comparison, 100% (137/137 of the first litter offspring of PH chimeras were confirmed as ESC-derived. Together, these data demonstrate that the PH approach increases the probability of germline transmission and speeds the generation of ESC derived animals from chimeras. Collectively, this approach reduces the time and costs inherent in the

  9. Incentives for methane mitigation and energy-efficiency improvements in the case of Ukraine's natural gas transmission system

    Roshchanka, Volha; Evans, Meredydd

    2014-06-01

    Reducing methane losses is a concern for climate change policy and energy policy. The energy sector is the major source of anthropogenic methane emissions into the atmosphere in Ukraine. Reducing methane emissions and avoiding combustion can be very cost-effective, but various barriers prevent such energy-efficiency measures from taking place. To date, few examples of industry-wide improvements exist. One example of substantial investments into upgrading natural gas transmission system comes from Ukraine's natural gas transmission company, Ukrtransgaz. The company's investments into system upgrades, along with a 34% fall in throughput, resulted in reduction of Ukrtransgaz system's own consumption of natural gas by 68% in 2011 compared to the level in 2005. Evaluating reductions in methane emissions is challenging because of lack of accurate data and gaps in accounting methodologies. At the same time, Ukraine's transmission system has undergone improvements that, at the very least, have contained methane emissions, if not substantially reduced them. In this paper, we describe recent developments in Ukraine's natural gas transmission system and analyze the incentives that forced the sector to pay close attention to its methane losses. Ukraine is one of the most energy-intensive countries, among the largest natural gas consumers in the world, and a significant emitter of methane. The country is also dependent on imports of natural gas. A combination of several factors has created conditions for successful reductions in methane emissions and combustion. These factors include: an eightfold increase in the price of imported natural gas; comprehensive domestic environmental and energy policies, such as the Laws of Ukraine on Protecting the Natural Environment and on Air Protection; policies aimed at integration with European Union's energy market and accession to the Energy Community Treaty; and the country's participation in international cooperation on environment, such

  10. Korea's emission trading scheme and policy design issues to achieve market-efficiency and abatement targets

    In 2008, the government of Republic of Korea (Korea) announced the national abatement target aiming at 30% reductions from the Business-as-Usual projections by 2020. Accordingly, the Emission Trading Scheme (ETS) will be implemented from 2015 onwards. As ETS performance substantially depends on the structural design, it is critically important to examine the details of Korean ETS for the achievement of cost effectiveness and concurrent development of an active emission trading market. This paper addresses several policy design issues for this purpose. After providing an overview on the current framework of Korean ETS, we propose ways to achieve flexibility, consistency and market efficiency of the program in consideration of the preexisting policies. Issues in policy design are discussed by focusing on allowance allocation, market stabilization measures and price mechanism in the emission and energy markets in Korea. This paper will serve as a practical guideline for establishing sustainable and market-efficient Korean ETS that can be compatible with the international standards as in the EU ETS. - Highlights: • Emission Trading Scheme (ETS) will be implemented from 2015 in Korea to reduce CO2. • ETS performance substantially depends on structural design. • We provide policy overview on the current framework of Korean ETS. • Several policy design issues are discussed for developing policy consistency. • We focus on allowance allocation, allowance reserve and market stabilization measures

  11. SVANET: A Smart Vehicular Ad Hoc Network for Efficient Data Transmission with Wireless Sensors

    Prasan Kumar Sahoo; Ming-Jer Chiang; Shih-Lin Wu

    2014-01-01

    Wireless sensors can sense any event, such as accidents, as well as icy roads, and can forward the rescue/warning messages through intermediate vehicles for any necessary help. In this paper, we propose a smart vehicular ad hoc network (SVANET) architecture that uses wireless sensors to detect events and vehicles to transmit the safety and non-safety messages efficiently by using different service channels and one control channel with different priorities. We have developed a data transmissio...

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

    Dayan Adionel Guimarães

    2015-05-01

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

  13. Use of open space box: supporting tele-medicine in space through efficient data transmission

    Mohammad, Atif F.; Straub, Jeremy

    2015-05-01

    This paper presents a framework for a denormalized data ingestion and egress method which can be used among several types of in-space devices. Open Space Box is a novel model of communication that supports the data processing required to transform this data into products for utilization by the requesting stakeholders. One such set of data is the data that could be generated from a space-based 3D scanner. We provide an overview of 3D scanning technologies and discuss the storage/transmission needs and types of data generated by an optical 3D scanner developed and deployed at the University of North Dakota. Prospective usage patterns are discussed, as might be applicable to its use for regularly assessing astronauts' health and performing scientific experiments. Communication of this sort of data may be critical to the health of astronauts and to scientific mission goals and ongoing operations. Some of this data may be processed even before it is transmitted to the attending healthcare provider or requesting scientist. Given that the data communications to and from a spacecraft or space station happens at a limited rate and the massive amounts of data that could be generated from 3D scanning, the receiver or egress application to prepare data needs to be designed to transmit and receive data via an application with a flexible protocol base.

  14. Ka-Band TWT High-Efficiency Power Combiner for High-Rate Data Transmission

    Wintucky, Edwin G.; Simons, Rainee; Vaden, Karl R.; Lesny, Gary G.; Glass, Jeffrey L.

    2007-01-01

    A four-port magic-T hybrid waveguide junction serves as the central component of a high-efficiency two-way power combiner circuit for transmitting a high-rate phase-modulated digital signal at a carrier frequency in the Ka-band (between 27 and 40 GHz). This power combiner was developed to satisfy a specific requirement to efficiently combine the coherent outputs of two traveling-wavetube (TWT) amplifiers that are typically characterized by power levels on the order of 100 W or more. In this application, the use of a waveguide-based power combiner (instead of a coaxial-cable- or microstrip-based power combiner, for example) is dictated by requirements for low loss, high power-handling capability, and broadband response. Combiner efficiencies were typically 90 percent or more over both the linear and saturated output power regions of operation of the TWTs . Figure 1 depicts the basic configuration of the magic-T hybrid junction. The coherent outputs of the two TWTs enter through ports 1 and 4. As a result of the orientations of the electromagnetic fields, which also provides a needed high port-to-port isolation, of these two input signals and the interior design of the magic-T junction, the input powers are divided so as to add in phase at one output port (port 2), and to be opposite in phase and hence cancel each other at the opposite coplanar output port (port 3). The net result is that the output power at port 2 is essentially double that of the output of one TWT, minus the power lost in the magic-T hybrid junction. Optimum performance as a high-efficiency power combiner thus requires a balance of both power and phase at the input ports of the magic-T. Replicas of this two-way combiner can be arranged in a binary configuration to obtain a 2n-way (where n is an integer) combiner. For example, Figure 2 illustrates the use of three two-way combiners to combine the outputs of four TWTs.

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

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

    1986-01-01

    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.

  16. Designing large, high-efficiency, high-numerical-aperture, transmissive meta-lenses for visible light

    Byrnes, Steven J; Aieta, Francesco; Capasso, Federico

    2015-01-01

    A metasurface lens (meta-lens) is a lens that bends light with an array of nanostructures on a flat surface, rather than by refraction. Macroscopic meta-lenses (mm- to cm-scale diameter) have been quite difficult to simulate and optimize, due to the large area, the lack of periodicity, and the billions of adjustable parameters. We describe a method for designing a large-area meta-lens that allows not only prediction of the efficiency and far-field, but also optimization of the shape and position of each individual nanostructure, with a computational cost that is almost independent of the lens size. Loosely speaking, the technique consists of designing a series of metasurface beam deflectors (blazed gratings), and then gluing them together. As a test of this framework, we design some high-numerical-aperture (NA=0.94) meta-lenses for visible light, based on TiO2 nano-pillars on a glass substrate. One of our designs is predicted to focus unpolarized 580nm light with 79% predicted efficiency; another focuses 580n...

  17. Heralded high-efficiency quantum repeater with atomic ensembles assisted by faithful single-photon transmission.

    Li, Tao; Deng, Fu-Guo

    2015-01-01

    Quantum repeater is one of the important building blocks for long distance quantum communication network. The previous quantum repeaters based on atomic ensembles and linear optical elements can only be performed with a maximal success probability of 1/2 during the entanglement creation and entanglement swapping procedures. Meanwhile, the polarization noise during the entanglement distribution process is harmful to the entangled channel created. Here we introduce a general interface between a polarized photon and an atomic ensemble trapped in a single-sided optical cavity, and with which we propose a high-efficiency quantum repeater protocol in which the robust entanglement distribution is accomplished by the stable spatial-temporal entanglement and it can in principle create the deterministic entanglement between neighboring atomic ensembles in a heralded way as a result of cavity quantum electrodynamics. Meanwhile, the simplified parity-check gate makes the entanglement swapping be completed with unity efficiency, other than 1/2 with linear optics. We detail the performance of our protocol with current experimental parameters and show its robustness to the imperfections, i.e., detuning and coupling variation, involved in the reflection process. These good features make it a useful building block in long distance quantum communication. PMID:26502993

  18. Efficient Transmission of Multicast MAPs in IEEE 802.16e

    Yeom, Jae-Heung; Lee, Yong-Hwan

    The institute of electrical and electronics engineers (IEEE) 802.16e is designed to support a wide range of applications with various quality of service requirements. Since MAP signaling overhead can unacceptably be large for voice traffic, IEEE 802.16e suggests the use of multicast sub-MAPS whose messages are encoded according to the channel condition. In this case, it is desirable for the base station to properly choose a modulation and coding set associated with the channel condition. In this letter, we consider the use of an adaptive modulation coding scheme for the multicast sub-MAPs without explicit information on the channel condition. The proposed scheme can achieve the same MAP coverage as the broadcast MAP while minimizing the signaling overhead. Simulation results show that when it is applied to voice-over-internet protocol (VoIP) services, the proposed scheme can significantly enhance the VoIP capacity.

  19. From here to efficiency : time lags between the introduction of new technology and the achievement of fuel savings

    In this paper, the energy savings of new technology offering significant improvements in fuel efficiency are tracked for over 20 years as vehicles incorporating that technology enter the fleet and replace conventional light-duty vehicles. Two separate analyses are discussed: a life-cycle analysis of aluminum-intensive vehicles and a fuel-cycle analysis of the energy and greenhouse gas emissions of double vs. triple fuel-economy vehicles. In both efforts, market-penetration modeling is used to simulate the rate at which new technology enters the new fleet, and stock-adjustment modeling is used to capture the inertia in turnover of new and existing current-technology vehicles. Together, these two effects--slowed market penetration and delayed vehicle replacement--increase the time lag between market introduction and the achievement of substantial energy savings. In both cases, 15-20 years elapse, before savings approach these levels

  20. Hydraulic transmissivity and heat exchange efficiency of open fractures: a model based on lowpass filtered apertures

    Neuville, Amélie; Schmittbuhl, Jean; 10.1111/j.1365-246X.2011.05126.x

    2011-01-01

    Natural open joints in rocks commonly present multi-scale self-affine apertures. This geometrical complexity affects fluid transport and heat exchange between the flow- ing fluid and the surrounding rock. In particular, long range correlations of self-affine apertures induce strong channeling of the flow which influences both mass and heat advection. A key question is to find a geometrical model of the complex aperture that describes at best the macroscopic properties (hydraulic conductivity, heat exchange) with the smallest number of parameters. Solving numerically the Stokes and heat equa- tions with a lubrication approximation, we show that a low pass filtering of the aperture geometry provides efficient estimates of the effective hydraulic and thermal properties (apertures). A detailed study of the influence of the bandwidth of the lowpass filtering on these transport properties is also performed. For instance, keeping the information of amplitude only of the largest Fourier length scales allows us to rea...

  1. Localization, Concentration, and Transmission Efficiency of Banana bunchy top virus in Four Asexual Lineages of Pentalonia aphids

    Alberto Bressan

    2013-02-01

    Full Text Available Banana bunchy top virus (BBTV is the most destructive pathogenic virus of banana plants worldwide. The virus is transmitted in a circulative non-propagative manner by the banana aphid, Pentalonia nigronervosa Coquerel. In this work, we examined the localization, accumulation, and transmission efficiency of BBTV in four laboratory-established lineages of Pentalonia aphids derived from four different host plants: taro (Colocasia esculenta, heliconia (Heliconia spp., red ginger (Alpinia purpurata, and banana (Musa sp.. Mitochondrial sequencing identified three and one lineages as Pentalonia caladii van der Goot, a recently proposed species, and P. nigronervosa, respectively. Microsatellite analysis separated the aphid lineages into four distinct genotypes. The transmission of BBTV was tested using leaf disk and whole-plant assays, both of which showed that all four lineages are competent vectors of BBTV, although the P. caladii from heliconia transmitted BBTV to the leaf disks at a significantly lower rate than did P. nigronervosa. The concentration of BBTV in dissected guts, haemolymph, and salivary glands was quantified by real-time PCR. The BBTV titer reached similar concentrations in the guts, haemolymph, and salivary glands of aphids from all four lineages tested. Furthermore, immunofluorescence assays showed that BBTV antigens localized to the anterior midguts and the principal salivary glands, demonstrating a similar pattern of translocations across the four lineages. The results reported in this study showed for the first time that P. caladii is a competent vector of BBTV.

  2. Localization, concentration, and transmission efficiency of Banana bunchy top virus in four asexual lineages of Pentalonia aphids.

    Watanabe, Shizu; Greenwell, April M; Bressan, Alberto

    2013-02-01

    Banana bunchy top virus (BBTV) is the most destructive pathogenic virus of banana plants worldwide. The virus is transmitted in a circulative non-propagative manner by the banana aphid, Pentalonia nigronervosa Coquerel. In this work, we examined the localization, accumulation, and transmission efficiency of BBTV in four laboratory-established lineages of Pentalonia aphids derived from four different host plants: taro (Colocasia esculenta), heliconia (Heliconia spp.), red ginger (Alpinia purpurata), and banana (Musa sp.). Mitochondrial sequencing identified three and one lineages as Pentalonia caladii van der Goot, a recently proposed species, and P. nigronervosa, respectively. Microsatellite analysis separated the aphid lineages into four distinct genotypes. The transmission of BBTV was tested using leaf disk and whole-plant assays, both of which showed that all four lineages are competent vectors of BBTV, although the P. caladii from heliconia transmitted BBTV to the leaf disks at a significantly lower rate than did P. nigronervosa. The concentration of BBTV in dissected guts, haemolymph, and salivary glands was quantified by real-time PCR. The BBTV titer reached similar concentrations in the guts, haemolymph, and salivary glands of aphids from all four lineages tested. Furthermore, immunofluorescence assays showed that BBTV antigens localized to the anterior midguts and the principal salivary glands, demonstrating a similar pattern of translocations across the four lineages. The results reported in this study showed for the first time that P. caladii is a competent vector of BBTV. PMID:23435241

  3. Bidirectional Packet Aggregation and Coding for Efficient VoIP Transmission in Wireless Multi-Hop Networks

    Hasegawa, Jun; Yomo, Hiroyuki; Kondo, Yoshihisa; Davis, Peter; Sakakibara, Katsumi; Miura, Ryu; Obana, Sadao

    This paper proposes bidirectional packet aggregation and coding (BiPAC), a packet mixing technique which jointly applies packet aggregation and network coding in order to increase the number of supportable VoIP sessions in wireless multi-hop mesh networks. BiPAC applies network coding for aggregated VoIP packets by exploiting bidirectional nature of VoIP sessions, and largely reduces the required protocol overhead for transmitting short VoIP packets. We design BiPAC and related protocols so that the operations of aggregation and coding are well-integrated while satisfying the required quality of service by VoIP transmission, such as delay and packet loss rate. Our computer simulation results show that BiPAC can increase the number of supportable VoIP sessions maximum by around 87% as compared with the case when the packet aggregation alone is used, and 600% in comparison to the transmission without aggregation/coding. We also implement BiPAC in a wireless testbed, and run experiments in an actual indoor environment. Our experimental results show that BiPAC is a practical and efficient forwarding method, which can be implemented into the current mesh hardware and network stack.

  4. A reconfigurable waveguide for energy-efficient transmission and local manipulation of information in a nanomagnetic device

    Haldar, Arabinda; Kumar, Dheeraj; Adeyeye, Adekunle Olusola

    2016-05-01

    Spin-wave-based devices promise to usher in an era of low-power computing where information is carried by the precession of the electrons' spin instead of dissipative translation of their charge. This potential is, however, undermined by the need for a bias magnetic field, which must remain powered on to maintain an anisotropic device characteristic. Here, we propose a reconfigurable waveguide design that can transmit and locally manipulate spin waves without the need for any external bias field once initialized. We experimentally demonstrate the transmission of spin waves in straight as well as curved waveguides without a bias field, which has been elusive so far. Furthermore, we experimentally show a binary gating of the spin-wave signal by controlled switching of the magnetization, locally, in the waveguide. The results have potential implications in high-density integration and energy-efficient operation of nanomagnetic devices at room temperature.

  5. A reconfigurable waveguide for energy-efficient transmission and local manipulation of information in a nanomagnetic device.

    Haldar, Arabinda; Kumar, Dheeraj; Adeyeye, Adekunle Olusola

    2016-05-01

    Spin-wave-based devices promise to usher in an era of low-power computing where information is carried by the precession of the electrons' spin instead of dissipative translation of their charge. This potential is, however, undermined by the need for a bias magnetic field, which must remain powered on to maintain an anisotropic device characteristic. Here, we propose a reconfigurable waveguide design that can transmit and locally manipulate spin waves without the need for any external bias field once initialized. We experimentally demonstrate the transmission of spin waves in straight as well as curved waveguides without a bias field, which has been elusive so far. Furthermore, we experimentally show a binary gating of the spin-wave signal by controlled switching of the magnetization, locally, in the waveguide. The results have potential implications in high-density integration and energy-efficient operation of nanomagnetic devices at room temperature. PMID:26828846

  6. Can Efficient Technology Transfer Be Achieved through a Hybrid Corporate Culture? A Study on Japanese Manufacturing Subsidiaries in Vietnam

    Nguyen Thi Duc Nguyen

    2012-03-01

    Full Text Available This study aims to explore the positive manners of dealing with cultural differences to efficiently implementtechnology transfer for Japanese subsidiaries in Vietnam. Based on Hofstede’s cultural dimensions theory, thestudy, which employed qualitative data collection approaches, including in-depth interviews, focus groupdiscussions, and observations, was conducted at thirteen Japanese manufacturing subsidiaries in Vietnam. Thedata were further analyzed using Adler’s framework on intercultural interaction synergy. The results were: (1Differences between Vietnamese and Japanese management existing in implementing technology transfer aretraced back to each national culture fundamental, mainly lie on dimensions of Collectivism and Power Distance;and (2 strategic activities directly convincing Vietnamese staff behaviors and addressing the mindset ofJapanese and Vietnamese staff were taken to minimize the above differences. This study proposes the workingframework towards hybrid corporate culture that flexibly incorporates local practices while maintaining coreJapanese management. It can help achieve efficiently technology transfer performance for Japanese firms doingbusiness in developing countries, especially Vietnam.

  7. Highly efficient data transmission facility through very long distance high-speed networks

    For global collaboration as a large scale scientific project, utilization of very high-speed, long distance internet is essential part of the research infrastructure. By the rapid progress of network technology very high-speed networks are connecting research institutes all over the world and network bandwidth grows and grows. Currently, 10 Gbps network is commonly used and 40 and 100 Gbps network is coming. As the network bandwidth increase, it becomes more difficult to use network efficiently, especially when we use TCP/IP. Furthermore, parallel TCP/IP streams are known to be much more difficult to utilize than single TCP/IP stream. To tackle with these problems, we developed a middle-hardware approach to take care of network streams with wire-rate speed; a programmable hardware framework on which we can realize a network function by developing a firmware for FPGA. We design a middle-hardware-box consists of 5-port network interface and FPGA with large buffer memories, whose firmware can be changed dynamically for the flexibility. Middle-Hardware-Box can be used as a proxy to be settled at the entrance between LAN and WAN, as well as used as a terminal-node to sends and receives packets from and to the network. One of the important features is, it can handle each stream of TCP separately. As the result, all streams between cluster systems can be handled at the gateway, and are controlled by fine-grained scheduling and placing. Since 2001, we have developed 'Data Reservoir System' to transfer huge amount of data between clusters settled in long distant places using parallel TCP streams. For fast data transfer, the important issues are (1) single stream performance is high and (2) performance of each stream is balanced. We performed long distance network experiments to evaluate the effect of our approach. We used network path from Tokyo to Seattle, Usa with a 10 Gbps WAN PHY link. The results of experiments show that four TCP/IP streams on a 10 Gbps link are

  8. Highly efficient data transmission facility through very long distance high-speed networks

    This document is made of the slides of the presentation. For global collaboration as a large scale scientific project, utilization of very high-speed, long distance internet is essential part of the research infrastructure. By the rapid progress of network technology, such as optical fiber and network switches, very high-speed networks are connecting research institutes all over the world and network bandwidth grows and grows. Currently, 10 Gbps network is commonly used and 40 and 100 Gbps network is coming. As the network bandwidth increase, it becomes more difficult to use network efficiently, especially when we use TCP/IP. Furthermore, parallel TCP/IP streams are known to be much more difficult to utilize than single TCP/IP stream. To tackle with these problems, we developed a middle-hardware approach to take care of network streams with wire-rate speed; a programmable hardware framework on which we can realize a network function by developing a firmware for FPGA. We design a middle-hardware-box consists of 5-port network interface and FPGA with large buffer memories, whose firmware can be changed dynamically for the flexibility. Middle-Hardware-Box can be used as a proxy to be settled at the entrance between LAN and WAN, as well as used as a terminal-node to sends and receives packets from and to the network. One of the important features is, it can handle each stream of TCP separately. As the result, all streams between cluster systems can be handled at the gateway, and are controlled by fine-grained scheduling and placing. Since 2001, we have developed 'Data Reservoir System' to transfer huge amount of data between clusters settled in long distant places using parallel TCP streams. For fast data transfer, the important issues are (1) single stream performance is high and (2) performance of each stream is balanced. At the same time, to improve the performance, network environment is very important both as a test environment, that is, artificial network inside

  9. Hands-On, Demonstration, and Videotape Laboratories for Non-Science Majors in a Food Science Course: Achievement, Attitude, and Efficiency

    Johnson, H. L.; Trout, B. L.; Brekke, C. J.; Luedecke, L. O.

    2004-01-01

    Student achievement, attitude, and instructional efficiency were determined for hands-on and for live and videotape demonstration laboratories for nonscience majors. Each of 3 laboratory sections experienced 3 different teaching methods for one 4-wk unit. No significant difference in achievement was found among the laboratory methods. An attitude…

  10. Lab-scale investigation of Middle-Bosnia coals to achieve high-efficient and clean combustion technology

    Smajevic Izet

    2014-01-01

    Full Text Available This paper describes full lab-scale investigation of Middle-Bosnia coals launched to support selection an appropriate combustion technology and to support optimization of the boiler design. Tested mix of Middle-Bosnia brown coals is projected coal for new co-generation power plant Kakanj Unit 8 (300-450 MWe, EP B&H electricity utility. The basic coal blend consisting of the coals Kakanj: Breza: Zenica at approximate mass ratio of 70:20:10 is low grade brown coal with very high percentage of ash - over 40%. Testing that coal in circulated fluidized bed combustion technique, performed at Ruhr-University Bohum and Doosan Lentjes GmbH, has shown its inconveniency for fluidized bed combustion technology, primarily due to the agglomeration problems. Tests of these coals in PFC (pulverized fuel combustion technology have been performed in referent laboratory at Faculty of Mechanical Engineering of Sarajevo University, on a lab-scale PFC furnace, to provide reliable data for further analysis. The PFC tests results are fitted well with previously obtained results of the burning similar Bosnian coal blends in the PFC dry bottom furnace technique. Combination of the coals shares, the process temperature and the air combustion distribution for the lowest NOx and SO2 emissions was found in this work, provided that combustion efficiency and CO emissions are within very strict criteria, considering specific settlement of lab-scale furnace. Sustainability assessment based on calculation economic and environmental indicators, in combination with Low Cost Planning method, is used for optimization the power plant design. The results of the full lab-scale investigation will help in selection optimal Boiler design, to achieve sustainable energy system with high-efficient and clean combustion technology applied for given coals.

  11. Numerical analysis of ion-funnel transmission efficiency in an API-MS system with a continuum/microscopic approach.

    Gimelshein, Sergey; Lilly, Taylor; Moskovets, Eugene

    2015-11-01

    A multi-step numerical approach is used to analyze the efficiency of an ion-funnel to transport ions over a wide range of m/z. A continuum approach based on the solution of the Navier-Stokes equations is applied to model the gas flow through a capillary connecting the atmospheric and subatmospheric sections of a mass spectrometer. A microscopic, fully kinetic approach based on the solution of the Boltzmann equation is used to examine the ion and gas transport through an ion-funnel kept at a 0.1-3 Torr pressure to the quadrupole section kept at a 0.01 Torr pressure. In addition to aerodynamic drag, the developed approach takes into account the combined effect of the DC field driving the ions downstream toward the funnel exit, the rf field confining the ions in radial direction, and the space charge causing ion repulsion. The sensitivity of the ion transmission to the gas pressure in the ion-funnel, the rf, and the total ion current injected to the funnel from capillary nozzle is shown. Graphical Abstract ᅟ. PMID:26242805

  12. Power Efficiency Improvement in CE-OFDM System With 0 dB IBO for Transmission over PLC Network

    El Ghzaoui Mohammed, Belkadid Jamal, Benbassou Ali & EL Bekkali Moulhim

    2011-08-01

    Full Text Available Orthogonal frequency division multiplexing (OFDM OFDM has been adopted for high speeddata transmission of multimedia traffic such as HomePlug A/V and Mobile WiMax. However,OFDM also has a drawback of a high PAPR (peak-to-average-power-ratio. Due to this highPAPR amplifier usually does not act in dynamic range. One potential solution for reducing thepeak-to-average power ratio (PAPR in an OFDM system is to utilize a constant envelopeOFDM (CE-OFDM system. Furthermore, by utilizing continuous phase modulation (CPM ina CE-OFDM system, the PAPR can be effectively reduced to 0 dB, allowing for the signal tobe amplified with a power efficient non-linear power amplifier with Input Back-Off (IBO of 0dB. This paper describes a CE-OFDM based modem for Power Line Communications (PLCover the low voltage distribution network. Relying on a preliminary characterization of a PLCnetwork, a complete description of the modem is given. Also CE-OFDM is compared withconventional OFDM under HomePlug 1.0 in the presence of power amplifier nonlinearities,considering different values of IBO.

  13. Transmission : key to the Alberta market

    AltaLink is Canada's first independent transmission company with 11,000 kilometres (km) of lines and 250 substations. It possesses a unique ownership structure with strong technical partners and financial capability. No major transmission system has been built in the last fifteen years in Alberta. The author examined the situation of power transmission in Alberta, indicating that developments should include capacity increase out of Fort McMurray, and better market integration with both British Columbia and the Pacific Northwest. An efficient and effective market requires ample transmission capacity, which would allow for trade and competition, access for efficient generators, and access to regional markets. New transmission must be planned and achieved in a proactive manner. Generation developers must be assured that transmission will be available, and that tariffs and loss factors will be predictable and stable. figs

  14. Improvement The Transmission Efficiency For Wireless Packet Communication Systems Using Automatic Control for power And Time Slot Width Of Slotted Non persistent ISMA Protocol

    Saad M. Hardan

    2013-05-01

    Full Text Available In packed communication systems which use a protocol, the protocol should perform the allocation of channels such that the transmission channel is used efficiently. Efficiency is usually measured in terms of channel throughput and the average transmission  delay. The Slotted Nonpersistent ISMA protocol is one of random access protocols used in packed communication systems. In this research a Slotted Nonpersistent ISMA protocol Model with automatic control for power and time slot is proposed. the suggested algorithm enable the base station(access point to control  the protocol time slot length and  transmission power in a dynamic way to control the normalized propagation delay d and to maintain all the uplink signals in the limit of captured power threshold (capture ratio in order to control the  throughput and the average transmission delay of the communication system by an automatic method. the computer simulation results  confirm the activity of the  proposed algorithm for increasing the  throughput and decreasing the average transmission delay by an accepted ratios.

  15. The transmission mechanism of Xylella fastidiosa by sharpshooter vectors and a model for quantification of vector efficiency

    The exact mechanism of transmission (acquisition and inoculation) of Xylella fastidiosa (Xf) by sharpshooter vectors such as the glassy-winged sharpshooter, Homalodisca vitripennis (Germar), has been unknown. This presentation will summarize five years of work to identify the transmission mechanism...

  16. Using interlayer step-wise triplet transfer to achieve an efficient white organic light-emitting diode with high color-stability

    An efficient phosphorescent white organic light emitting-diode with a red-green-blue tri-emitting-layer structure is reported. The host of the red dopant possesses a lower triplet-energy than the green dye. An interlayer step-wise triplet transfer via blue dye → green dye → red host → red dye is achieved. This mechanism allows an efficient triplet harvesting by the three dopants, thus maintaining a balanced white light and reducing energy loss. Moreover, the color stability of the device is improved significantly. The white device not only achieves a peak external quantum efficiency of 21.1 ± 0.8% and power efficiency of 37.5 ± 1.4 lm/W but shows no color shift over a wide range of voltages

  17. Transmissions in vehicles 2010

    NONE

    2010-07-01

    Within the international VDI congress 'Gears in vehicles 2010' of the VDI Wissensforum GmbH (Duesseldorf, Federal Republic of Germany) between 22nd and 23rd June, 2010, in Friedrichshafen (Federal Republic of Germany), the following lectures were held: (1) 8HP70H - The moldhybrid transmission from ZF - Cjallenges and achievements (P. Gutmann); (2) GETRAG boosted range extender - A highly flexible electric powertrain for maximum CO{sub 2} reduction (S. Huepkes); (3) E-Transmission between full-hybrid and E-drive (P. Tenberge); (4) Reducing NO{sub x} and particulate emissions in electrified drivelines (R. Kuberczyk); (5) Simulation aided HEV and EV development: from the component to the whole powertrain (A. Gacometti); (6) Investigations on operating behaviour of the optimized CVT hybrid driveline (B.-R. Hoehn); (7) Customer-oriented dimensioning of electrified drivetrains (M. Eghtessad); (8) Decentralized optimal control strategy for parallel hybrid electric vehicles (A. Frenkel); (9) The new generation 6-speed automatic transmission AF40 (G. Bednarek); (10) Customized mechatronic solutions for integrated transmission control units (M. Wieczorek); (11) The optimal automatic transmission for front-transverse applications - Planetary transmissions or dual clutch transmissions? (G. Gumpoltsberger); (12) The new shift-by-wire gearshift lever for the Audi A8 - Requirements and concept (T. Guttenbergere); (13) The new shift-by-wire gearshift lever for the Audi A8 - Realization (A. Giefer); (14) Fuel-efficient transmissions of the future: Calculation of the efficiency factor for vehicle transmissions (B. Volpert); (15) HT-ACM: A new polymer generation for static and dynamic gearbox sealing solutions (E. Osen); (16) 'Energy efficiency equipped solutions by SKF' for power train applications - A contribution to CO{sub 2} - emission reduction and sustainability (T. Bobke); (17) 6-Ratio planetary shift transmission controlled by 4 external brakes, and design

  18. Determination of inlet transmission and conversion efficiencies for in situ measurements of the nocturnal nitrogen oxides, NO3, N2O5 and NO2, via pulsed cavity ring-down spectroscopy.

    Fuchs, Hendrik; Dubé, William P; Ciciora, Steven J; Brown, Steven S

    2008-08-01

    Pulsed cavity ring-down spectroscopy is a highly sensitive method for direct absorption spectroscopy that has been applied to in situ detection of NO3, N2O5 and NO2 in the atmosphere from a variety of platforms, including ships, aircraft, and towers. In this paper, we report the development of schemes to significantly improve the accuracy of these measurements. This includes the following: (1) an overall improvement in the inlet transmission efficiencies (92 +/- 2% for NO3 and 97 +/- 1% for N2O5) achieved primarily through a reduction in the inlet residence time; and (2) the development of a calibration procedure that allows regular determination of these efficiencies in the field by addition of NO3 or N2O5 to the inlet from a portable source followed by conversion of NO3 to NO2. In addition, the dependence of the instrument's sensitivity and accuracy to a variety of conditions encountered in the field, including variations in relative humidity, aerosol loading, and VOC levels, was systematically investigated. The rate of degradation of N2O5 transmission efficiency on the inlet and filter system due to the accumulation of inorganic aerosol was determined, such that the frequency of filter changes required for accurate measurements could be defined. In the absence of aerosol, the presence of varying levels of relative humidity and reactive VOC were found to be unimportant factors in the instrument's performance. The 1 sigma accuracy of the NO3, N2O5, and NO2 measured with this instrument are -9/+12, -8/+11, +/- 6%, respectively, where the -/+ signs indicate that the actual value is low/high relative to the measurement. The largest contribution to the overall uncertainty is now due to the NO3 absorption cross section rather than the inlet transmission efficiency. PMID:18588318

  19. Study on Transmission Efficiency Numerical Simulation of Rod String Based on Vibration Mechanics%基于振动力学的抽油杆柱传动效率数值仿真研究

    王素玲; 常瑞清; 刘勤志; 孙伟国; 徐广元

    2012-01-01

    The sucker rod string is one of the main components of the underground system of pumped well of pumping unit, its transmission efficiency has been neglected. In the process of transmitting load,the slender structure of the sucker rod string caused so large vibration that consumed more energy. Based on vibration theory and considering the conditions of the sucker rod string initial geometric imperfections,the sucker rod string dynamic instability of mechanical model was established. Adopting gap element theory,the dynamic collision of the sucker rod and tubing contact boundary was established as well,by using numerical solution techniques to simulate, three-dimensional vibration on the sucker rod string,and subsequently achieving transmission efficiency of sucker rod sting. Comparing the calculation results with the test results of the test wells,both can be concluded that they have better consistency. Analyzing the relationship of the transmission efficiency of the rod string and relevant parameters to quantify influence of the transmission efficiency on the rod string,these laid the theoretical foundation of underground efficiency.%抽油杆柱是抽油机并井下系统的主要组成之一,其传动效率一直被人们所忽视.由于抽油杆柱的细长结构,在传动载荷过程中引起较大的振动而消耗能量.根据振动理论,在考虑抽油杆柱初始几何缺陷条件下,建立抽油杆柱动态失稳的力学模型,采用间隙元理论,建立抽油杆与油管的动态碰撞接触边界,应用数值求解技术对抽油杆柱三维振动进行模拟,获得抽油杆柱的传动效率.将计算结果与试验井测试结果进行对比,两者具有较好的一致性,同时分析了杆柱传动效率与相关参数的关系,定量给出了对杆柱传动的效率影响,为提高井下效率奠定了理论基础.

  20. Quantum efficiency of transmission-mode AlxGa1-xAs/GaAs photocathodes with graded-composition and exponential-doping structure

    Feng, Cheng; Zhang, Yijun; Qian, Yunsheng; Xu, Yuan; Liu, Xinxin; Jiao, Gangcheng

    2016-06-01

    A transmission-mode AlxGa1-xAs/GaAs photocathode with the combination of composition-graded AlxGa1-xAs window layer and exponential-doping GaAs emission layer is developed to maximize the cathode performance. The theoretical quantum efficiency model with this complex structure containing twofold built-in electric fields is deduced by solving the one dimensional continuity equations combined with the three-step model. By comparison of spectral characteristics of photocathodes with different composition and doping structures, and through analysis of cathode structure parameters, it is found that the twofold built-in electric fields can effectively improve photoemission performance of AlxGa1-xAs/GaAs photocathode, which is related to Al proportion variation range and thicknesses of window layer and emission layer. The quantum efficiency model would provide theoretical guidance for better design of transmission-mode graded bandgap photocathodes.

  1. Grenada, OECS Fiscal Issues : Policies to Achieve Fiscal Sustainability and Improve Efficiency and Equity of Public Expenditures

    World Bank

    2004-01-01

    The report reviews Grenada public expenditures for the period 1995-02 and suggests policy recommendations to achieve fiscal sustainability, improve social service delivery, and reform social protection based on the economic situation of the country at the time. To restore rapid economic growth, ensure medium-term fiscal sustainability under the umbrella of the currency union and protect th...

  2. WIFI and WIMAX Optimization Design of Transmission and Application

    Wang, Peng; Wu, Xian Li

    WIFI (Wireless Fidelity) and WIMAX (Worldwide Interoperability for Microwave Access) using OFDM / OFDMA, MIMO technology to achieve speeds in a unified platform for data, voice, high-definition video and other wireless transmission, For many industries of wireless communication may be short, very considerable practical prospect. This paper focuses on WIFI and WIMAX transmission optimization design, including space-time coding (abbreviated as: STC), multiple-access control (MAC) protocol of the mathematical model; traffic channel terminal mobility cross-layer design to achieve multi-layer co-optimization, improve the WIFI and WIMAX, transmission efficiency, making WIFI and WIMAX transmission are more reasonable.

  3. Efficient algorithms for multi-sender data transmission in swarm-based peer-to-peer streaming systems

    Shen, Yuanbin

    2010-01-01

    In peer-to-peer (P2P) swarm-based streaming systems, each video sequence is typically divided into segments, which are then streamed from multiple senders to a receiver. The receiver needs to coordinate the senders by specifying a transmission schedule for each of them. Our goal is to compute the transmission schedules in order to maximize the video quality at the receivers. We prove that this problem is NP-Complete. We present an Integer Linear Programming (ILP) formulation for this problem....

  4. Dominica : OECS Fiscal Issues, Policies to Achieve Fiscal Sustainability and Improve Efficiency and Equity of Public Expenditures

    World Bank

    2005-01-01

    This report concludes that during FY1993/94 to FY002/03 the fiscal policy implemented by the government of Dominica was unsustainable and posed a risk to the stability of the currency board arrangement. Moreover, this report recommends that most of the adjustment required to achieve a sustainable fiscal policy needed to come from expenditure cuts, in particular a reduction in the number of established and non-established positions, and from focusing capital expenditures on projects geared to ...

  5. Carrots and Sticks: A Comprehensive Business Model for the Successful Achievement of Energy Efficiency Resource Standards Environmental Energy Technologies DivisionMarch 2011

    Satchwell, Andrew; Cappers, Peter; Goldman, Charles

    2011-03-22

    Energy efficiency resource standards (EERS) are a prominent strategy to potentially achieve rapid and aggressive energy savings goals in the U.S. As of December 2010, twenty-six U.S. states had some form of an EERS with savings goals applicable to energy efficiency (EE) programs paid for by utility customers. The European Union has initiated a similar type of savings goal, the Energy End-use Efficiency and Energy Services Directive, where it is being implemented in some countries through direct partnership with regulated electric utilities. U.S. utilities face significant financial disincentives under traditional regulation which affects the interest of shareholders and managers in aggressively pursuing cost-effective energy efficiency. Regulators are considering some combination of mandated goals ('sticks') and alternative utility business model components ('carrots' such as performance incentives) to align the utility's business and financial interests with state and federal energy efficiency public policy goals. European countries that have directed their utilities to administer EE programs have generally relied on non-binding mandates and targets; in the U.S., most state regulators have increasingly viewed 'carrots' as a necessary condition for successful achievement of energy efficiency goals and targets. In this paper, we analyze the financial impacts of an EERS on a large electric utility in the State of Arizona using a pro-forma utility financial model, including impacts on utility earnings, customer bills and rates. We demonstrate how a viable business model can be designed to improve the business case while retaining sizable ratepayer benefits. Quantifying these concerns and identifying ways they can be addressed are crucial steps in gaining the support of major stakeholder groups - lessons that can apply to other countries looking to significantly increase savings targets that can be achieved from their own utility

  6. Can Efficient Technology Transfer Be Achieved through a Hybrid Corporate Culture? A Study on Japanese Manufacturing Subsidiaries in Vietnam

    Nguyen Thi Duc Nguyen; Chikako Takanashi; Atsushi Aoyama

    2012-01-01

    This study aims to explore the positive manners of dealing with cultural differences to efficiently implementtechnology transfer for Japanese subsidiaries in Vietnam. Based on Hofstede’s cultural dimensions theory, thestudy, which employed qualitative data collection approaches, including in-depth interviews, focus groupdiscussions, and observations, was conducted at thirteen Japanese manufacturing subsidiaries in Vietnam. Thedata were further analyzed using Adler’s framework on intercultural...

  7. Low-cost and no-cost practice to achieve energy efficiency of government office buildings: A case study in federal territory of Malaysia

    Tahir, Mohamad Zamhari; Nawi, Mohd Nasrun Mohd; Ibrahim, Amlus

    2016-08-01

    This paper presents the findings of a case study to achieve energy-efficient performance of conventional office buildings in Malaysia. Two multi-storey office buildings in Federal Territory of Malaysia have been selected. The aim is to study building energy saving potential then to highlight the appropriate measures that can be implemented. Data was collected using benchmarking method by comparing the measured consumption to other similar office buildings and a series of preliminary audit which involves interviews, a brief review of utility and operating data as well as a walkthrough in the buildings. Additionally, in order to get a better understanding of major energy consumption in the selected buildings, general audit have been conducted to collect more detailed information about building operation. In the end, this study emphasized low-cost and no-cost practice to achieve energy efficiency with significant results in some cases.

  8. Limits on Achievable Dimensional and Photon Efficiencies with Intensity-Modulation and Photon-Counting Due to Non-Ideal Photon-Counter Behavior

    Moision, Bruce; Erkmen, Baris I.; Farr, William; Dolinar, Samuel J.; Birnbaum, Kevin M.

    2012-01-01

    An ideal intensity-modulated photon-counting channel can achieve unbounded photon information efficiencies (PIEs). However, a number of limitations of a physical system limit the practically achievable PIE. In this paper, we discuss several of these limitations and illustrate their impact on the channel. We show that, for the Poisson channel, noise does not strictly bound PIE, although there is an effective limit, as the dimensional information efficiency goes as e[overline] e PIE beyond a threshold PIE. Since the Holevo limit is bounded in the presence of noise, this illustrates that the Poisson approximation is invalid at large PIE for any number of noise modes. We show that a finite transmitter extinction ratio bounds the achievable PIE to a maximum that is logarithmic in the extinction ratio. We show how detector jitter limits the ability to mitigate noise in the PPM signaling framework. We illustrate a method to model detector blocking when the number of detectors is large, and illustrate mitigation of blocking with spatial spreading and altering. Finally, we illustrate the design of a high photon efficiency system using state-of-the-art photo-detectors and taking all these effects into account.

  9. Development of a Millimeter-Wave Beam Position and Profile Monitor for Transmission Efficiency Improvement in an ECRH System

    Shimozuma T.

    2015-01-01

    Full Text Available In a high power Electron Cyclotron Resonance Heating (ECRH system, a long-distance and low-loss transmission system is required to realize effective heating of nuclear fusion-relevant plasmas. A millimeter-wave beam position and profile monitor, which can be used in a high-power, evacuated, and cooled transmission line, is proposed, designed, manufactured, and tested. The beam monitor consists of a reflector, Peltier-device array and a heat-sink. It was tested using simulated electric heater power or gyrotron output power. The data obtained from the monitor were well agreed with the heat source position and profile. The methods of data analysis and mode-content analysis of a propagating millimeter-wave in the corrugated wave-guide are proposed.

  10. Particle Swarm Optimization as an Efficient Computational Method in order to Minimize Vibrations of Multimesh Gears Transmission

    Alexandre Carbonelli

    2011-01-01

    Full Text Available The aim of this work is to present the great performance of the numerical algorithm of Particle Swarm Optimization applied to find the best teeth modifications for multimesh helical gears, which are crucial for the static transmission error (STE. Indeed, STE fluctuation is the main source of vibrations and noise radiated by the geared transmission system. The microgeometrical parameters studied for each toothed wheel are the crowning, tip reliefs and start diameters for these reliefs. Minimization of added up STE amplitudes on the idler gear of a three-gear cascade is then performed using the Particle Swarm Optimization. Finally, robustness of the solutions towards manufacturing errors and applied torque is analyzed by the Particle Swarm algorithm to access to the deterioration capacity of the tested solution.