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Sample records for fr27ja10n transmission loading

  1. Load Distribution in Transmissions "Split"

    Science.gov (United States)

    Krantz, Timothy L.; Delgado, Irebert R.

    1998-01-01

    The transmission system of a helicopter must meet particularly critical requirements. It must transmit engine power to the rotor, at the same time ensuring a typical speed reduction of 60 to 1. It must also be safe, reliable, light, and reach a high level of performance while, at the same time, it must produce few vibrations and little noise. Helicopter transmissions have achieved high-level performances thanks to the combination of analyses, experiments, and the application of practical field experience. However, the new generation of helicopters will require transmission systems that are even safer, lighter, less noisy, and more reliable.

  2. LOADING OF MECHANICAL TRANSMISSION OF TROLLEYBUS TRACTION DRIVING GEAR

    Directory of Open Access Journals (Sweden)

    A. I. Safonov

    2009-01-01

    Full Text Available The paper analyzes factors that determine dynamic loads of mechanical transmission of trolleybus traction driving gear. The paper proposes a methodology for determination of calculative moments of loading transmission elements. Results of the research are analyzed and recommendations on  dynamic reduction of trolleybus transmission are given in the paper. 

  3. Final Project Report Load Modeling Transmission Research

    Energy Technology Data Exchange (ETDEWEB)

    Lesieutre, Bernard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bravo, Richard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yinger, Robert [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chassin, Dave [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Huang, Henry [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Ning [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hiskens, Ian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Venkataramanan, Giri [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-03-31

    The research presented in this report primarily focuses on improving power system load models to better represent their impact on system behavior. The previous standard load model fails to capture the delayed voltage recovery events that are observed in the Southwest and elsewhere. These events are attributed to stalled air conditioner units after a fault. To gain a better understanding of their role in these events and to guide modeling efforts, typical air conditioner units were testing in laboratories. Using data obtained from these extensive tests, new load models were developed to match air conditioner behavior. An air conditioner model is incorporated in the new WECC composite load model. These models are used in dynamic studies of the West and can impact power transfer limits for California. Unit-level and systemlevel solutions are proposed as potential solutions to the delayed voltage recovery problem.

  4. On dynamic loads in parallel shaft transmissions. 2: Parameter study

    Science.gov (United States)

    Lin, Edward Hsiang-Hsi; Huston, Ronald L.; Coy, John J.

    1987-01-01

    Solutions to the governing equations of a spur gear transmission model, developed in NASA TM-100180 (AVSCOM TM-87-C-2), are presented. Factors affecting the dynamic load are identified. It is found that the dynamic load increases with operating speed up to a system natural frequency. At operating speeds beyond the natural frequency the dynamic load decreases dramatically. Also. it is found that the applied load and shaft inertia have little effect on the dynamic load. Damping and friction decrease the dynamic load. Finally, tooth stiffness has a significant effect on dynamic loading; the higher the stiffness, the lower the dynamic loading. Also, the higher the stiffness the higher the rotating speed required for dynamic response.

  5. Load flow computations in hybrid transmission - distributed power systems

    NARCIS (Netherlands)

    Wobbes, E.D.; Lahaye, D.J.P.

    2013-01-01

    We interconnect transmission and distribution power systems and perform load flow computations in the hybrid network. In the largest example we managed to build, fifty copies of a distribution network consisting of fifteen nodes is connected to the UCTE study model, resulting in a system consisting

  6. Planet position errors in planetary transmission: Effect on load sharing and transmission error

    Science.gov (United States)

    Iglesias, Miguel; Fernández, Alfonso; De-Juan, Ana; Sancibrián, Ramón; García, Pablo

    2013-03-01

    In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

  7. Dynamic queuing transmission model for dynamic network loading

    DEFF Research Database (Denmark)

    Raovic, Nevena; Nielsen, Otto Anker; Prato, Carlo Giacomo

    2017-01-01

    This paper presents a new macroscopic multi-class dynamic network loading model called Dynamic Queuing Transmission Model (DQTM). The model utilizes ‘good’ properties of the Dynamic Queuing Model (DQM) and the Link Transmission Model (LTM) by offering a DQM consistent with the kinematic wave theory...... and allowing for the representation of multiple vehicle classes, queue spillbacks and shock waves. The model assumes that a link is split into a moving part plus a queuing part, and p that traffic dynamics are given by a triangular fundamental diagram. A case-study is investigated and the DQTM is compared...

  8. Load speed regulation in compliant mechanical transmission systems using feedback and feedforward control actions.

    Science.gov (United States)

    Raul, P R; Dwivedula, R V; Pagilla, P R

    2016-07-01

    The problem of controlling the load speed of a mechanical transmission system consisting of a belt-pulley and gear-pair is considered. The system is modeled as two inertia (motor and load) connected by a compliant transmission. If the transmission is assumed to be rigid, then using either the motor or load speed feedback provides the same result. However, with transmission compliance, due to belts or long shafts, the stability characteristics and performance of the closed-loop system are quite different when either motor or load speed feedback is employed. We investigate motor and load speed feedback schemes by utilizing the singular perturbation method. We propose and discuss a control scheme that utilizes both motor and load speed feedback, and design an adaptive feedforward action to reject load torque disturbances. The control algorithms are implemented on an experimental platform that is typically used in roll-to-roll manufacturing and results are shown and discussed.

  9. A Complex Frequency Method for A Loaded Resonant Cavity of Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    LIANGChanghong; LILong; SUTao; FANShengcai

    2004-01-01

    A complex frequency method for analyzing a loaded resonant cavity of transmission lines is presented in this paper. A sub-resonance system theory is used to treat the various loaded transmission lines cavity more effectively. Some practice examples are given to illustrate the application and validity of the proposed approach in this paper.

  10. On dynamic loads in parallel shaft transmissions. 1: Modelling and analysis

    Science.gov (United States)

    Lin, Edward Hsiang-Hsi; Huston, Ronald L.; Coy, John J.

    1987-01-01

    A model of a simple parallel-shaft, spur-gear transmission is presented. The model is developed to simulate dynamic loads in power transmissions. Factors affecting these loads are identified. Included are shaft stiffness, local compliance due to contact stress, load sharing, and friction. Governing differential equations are developed and a solution procedure is outlined. A parameter study of the solutions is presented in NASA TM-100181 (AVSCOM TM-87-C-3).

  11. Dynamic Efficiency of a Container Crane’s Hoisting Transmission System under Hoisting Dynamic Load

    Directory of Open Access Journals (Sweden)

    Yuanyuan Liu

    2016-01-01

    Full Text Available The dynamic efficiency of hoisting transmission system on a container crane is fundamental for accurate efficiency prediction, while the dynamic efficiency of hoisting transmission system has not been investigated sufficiently. This paper will focus on dynamic efficiency of hoisting transmission system under hoisting dynamic load. A power loss model of gearbox was built. Then the dynamic model of gear transmission was developed including time-varying mesh stiffness and hoisting dynamic load was studied. Power loss, dynamic efficiency, and equivalent static efficiency were conducted in hoisting and lowering working conditions. The result shows that dynamic efficiency which consists of the significant lower frequency component coincided with hoisting load torque of the higher frequency component which is directly related to dynamic mesh and bearing force. And in two processes, the equivalent static efficiency in constant speed stage is min, whereas maximum value occurs in different stage. The research results lay a foundation for hoisting gear transmission dynamic efficiency analysis.

  12. A Beacon Transmission Power Control Algorithm Based on Wireless Channel Load Forecasting in VANETs.

    Science.gov (United States)

    Mo, Yuanfu; Yu, Dexin; Song, Jun; Zheng, Kun; Guo, Yajuan

    2015-01-01

    In a vehicular ad hoc network (VANET), the periodic exchange of single-hop status information broadcasts (beacon frames) produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network.

  13. A Beacon Transmission Power Control Algorithm Based on Wireless Channel Load Forecasting in VANETs

    Science.gov (United States)

    Mo, Yuanfu; Yu, Dexin; Song, Jun; Zheng, Kun; Guo, Yajuan

    2015-01-01

    In a vehicular ad hoc network (VANET), the periodic exchange of single-hop status information broadcasts (beacon frames) produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network. PMID:26571042

  14. A Beacon Transmission Power Control Algorithm Based on Wireless Channel Load Forecasting in VANETs.

    Directory of Open Access Journals (Sweden)

    Yuanfu Mo

    Full Text Available In a vehicular ad hoc network (VANET, the periodic exchange of single-hop status information broadcasts (beacon frames produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network.

  15. Real Time Load Optimisation of Cable Based Transmission Grids

    DEFF Research Database (Denmark)

    Olsen, Rasmus Schmidt; Holbøll, Joachim; Guðmundsdottir, Unnur Stella

    2011-01-01

    Energinet.dk has launched an investigation of dynamic current ratings of cable based transmission grids, where both internal and external parameters are variables. The first topic was to investigate state of the art within calculating the current carrying capacity (ampacity or loadability...

  16. Impacts of Climate Change on Electric Transmission Capacity and Peak Electricity Load in the United States

    Science.gov (United States)

    Chester, M.; Bartos, M. D.; Eisenberg, D. A.; Gorman, B.; Johnson, N.

    2015-12-01

    Climate change may hinder future electricity reliability by reducing electric transmission capacity while simultaneously increasing electricity demand. This study estimates potential climate impacts to electric transmission capacity and peak electricity load in the United States. Electric power cables suffer decreased transmission capacity as they get hotter; similarly, during the summer peak period, electricity demand typically increases with hotter ambient air temperatures due to increased cooling loads. As atmospheric carbon concentrations increase, higher air temperatures may strain power infrastructure by reducing transmission capacity and increasing peak electricity loads. Taken together, these coincident impacts may have unpredictable consequences for electric power reliability. We estimate the effects of climate change on both the rated capacity of transmission infrastructure and expected electricity demand for 120 electrical utilities across the United States. We estimate climate-attributable capacity reductions to transmission lines by constructing thermal models of representative conductors, then forcing these models with downscaled CMIP5 temperature projections to determine the relative change in rated ampacity over the twenty-first century. Next, we assess the impact of climate change on electricity demand by using historical relationships between ambient temperature and utility-scale summertime peak load to estimate the extent to which climate change will incur additional peak load increases. We use downscaled temperature projections from 11 CMIP5 GCM models under 3 atmospheric carbon scenarios. We find that by mid-century (2040-2060), climate change may reduce average summertime transmission capacity by 4-6% relative to the 1990-2010 reference period. At the same time, peak summertime loads may rise by roughly 2-12% on average due to increases in daily maximum air temperature. In the absence of energy efficiency gains, demand-side management programs

  17. The design and analysis of single flank transmission error testor for loaded gears

    Science.gov (United States)

    Houser, D. R.; Bassett, D. E.

    1985-01-01

    Due to geometrical imperfections in gears and finite tooth stiffnesses, the motion transmitted from an input gear shaft to an output gear shaft will not have conjugate action. In order to strengthen the understanding of transmission error and to verify mathematical models of gear transmission error, a test stand that will measure the transmission error of a gear pair at operating loads, but at reduced speeds would be desirable. This document describes the design and development of a loaded transmission error tester. For a gear box with a gear ratio of one, few tooth meshing combinations will occur during a single test. In order to observe the effects of different tooth mesh combinations and to increase the ability to load test gear pairs with higher gear ratios, the system was designed around a gear box with a gear ratio of two.

  18. A Hybrid LCC-VSC HVDC Transmission System Supplying a Passive Load

    Science.gov (United States)

    Kotb, Omar

    High Voltage Direct Current (HVDC) transmission systems continue to be an excellent asset in modern power systems, mainly for their ability to overcome the problems of AC transmission, such as the interconnection of asynchronous grids, stability of long transmission lines, and use of long cables for power transmission. In the past 20 years, Voltage Source Converter (VSC)-HVDC transmission systems were developed and installed in many projects, thereby adding more operational benefits to DC transmission option, such as high controllability, ability to supply weak networks, and reduced converter reactive power demand. Nevertheless, VSC-HVDC transmission suffers from the disadvantages of high losses and cost. In this research, a hybrid HVDC employing a Line Commutated Converter (LCC) as rectifier and a VSC as inverter is used to supply a passive network through a DC cable. The hybrid system is best suited for unidirectional power transmission scenarios, such as power transmission to islands and remote load centers, where the construction of new transmission lines is prohibitively expensive. Control modes for the rectifier and inverter are selected and implemented using Proportional Integral (PI) controllers. Special control schemes are developed for abnormal operating conditions such as starting at light load and recovering from AC network faults. The system performance under steady state and transient conditions is investigated by EMTP-RV simulations. The results show the feasibility of the hybrid system.

  19. Load-Sharing Characteristics of Power-Split Transmission System Based on Deformation Compatibility and Loaded Tooth Contact Analysis

    Directory of Open Access Journals (Sweden)

    Hao Dong

    2015-01-01

    Full Text Available In order to implement the uniform load distribution of the power-split transmission system, a pseudostatic model is built. Based on the loaded tooth contact analysis (LTCA technique, the actual meshing process of each gear pair is simulated and the fitting curve of time-varying mesh stiffness is obtained. And then, the torsional angle deformation compatibility conditions are proposed according to the closed-loop characteristic of power flow, which will be combined with the torque equilibrium conditions and elastic support conditions to calculate the transfer torque of each gear pair. Finally, the load-sharing coefficient of the power-split transmission system is obtained, and the influences of the installation errors are analyzed. The results show that the above-mentioned installation errors comprehensively influence the load-sharing characteristics, and the reduction of only one error could not effectively achieve perfect load-sharing characteristics. Allowing for the spline clearance floating and constrained by the radial spacing ring, the influence of the floating pinion is analyzed. It shows that the floating pinion can improve the load-sharing characteristics. Through the comparison between the theoretical and related experimental data, the reasonability and feasibility of the above-proposed method and model are verified.

  20. Symmetry-Related Electromagnetic Properties of Resonator-Loaded Transmission Lines and Applications

    Directory of Open Access Journals (Sweden)

    Jordi Naqui

    2015-05-01

    Full Text Available This paper reviews the recent progress in the analysis and applications of the symmetry-related electromagnetic properties of transmission lines loaded with symmetric configurations of resonant elements. It will be shown that the transmission characteristics of these reactively loaded lines can be controlled by the relative orientation between the line and the resonant elements. Two main types of loaded lines are considered: (i resonance-based structures; and (ii frequency-splitting structures. In resonance-based transmission lines, a line is loaded with a single resonant (and symmetric element. For a perfectly symmetric structure, the line is transparent if the line and resonator exhibit symmetry planes of different electromagnetic nature (electric or magnetic wall, whereas the line exhibits a notch (resonance in the transmission coefficient if the symmetry planes behave as either electric or magnetic walls (symmetric configuration, or if symmetry is broken. In frequency-splitting lines, paired resonators are typically loaded to the transmission line; the structure exhibits a single notch for the symmetric configuration, whereas generally two split notches appear when symmetry is disrupted. Applications of these structures include microwave sensors (e.g., contactless sensors of spatial variables, selective mode suppressors (of application in common-mode suppressed differential lines, for instance and spectral signature barcodes, among others.

  1. Minimum Load-curtailment in Transmission Network Planning Considering Integrated Wind Farms

    Institute of Scientific and Technical Information of China (English)

    CHEN Yan; WEN Jinyu; CHENG Shijie

    2011-01-01

    With the enlarging scale of integrated wind power, the transmission network expansion planning (TNEP) problem considering wind farms is more important than before. TNEP problem usually can be divided into two sub-problems. The first sub-problem is to determine the new planning scheme in some way, and the second sub-problem is to assess the security and reliability of the transmission network planning scheme using the minimum load-shedding index.

  2. The design and analysis of single flank transmission error tester for loaded gears

    Science.gov (United States)

    Bassett, Duane E.; Houser, Donald R.

    1987-01-01

    To strengthen the understanding of gear transmission error and to verify mathematical models which predict them, a test stand that will measure the transmission error of gear pairs under design loads has been investigated. While most transmission error testers have been used to test gear pairs under unloaded conditions, the goal of this report was to design and perform dynamic analysis of a unique tester with the capability of measuring the transmission error of gears under load. This test stand will have the capability to continuously load a gear pair at torques up to 16,000 in-lb at shaft speeds from 0 to 5 rpm. Error measurement will be accomplished with high resolution optical encoders and the accompanying signal processing unit from an existing unloaded transmission error tester. Input power to the test gear box will be supplied by a dc torque motor while the load will be applied with a similar torque motor. A dual input, dual output control system will regulate the speed and torque of the system. This control system's accuracy and dynamic response were analyzed and it was determined that proportional plus derivative speed control is needed in order to provide the precisely constant torque necessary for error-free measurement.

  3. High-voltage transmission tower-line system subjected to disaster loads

    Institute of Scientific and Technical Information of China (English)

    LI Hongnan; BAI Haifeng

    2006-01-01

    The high-voltage power transmission system is an important lifeline structure. It is significant for wide researches on the features and ability of the system subjected to earthquake and environmental loads. The promising prosperity of the system has been demonstrated around the world. The corresponding advances of the system with respect to the mechanism of loading action, analytical methods, experimental research measurements, structural vibration control, fatigue damage, lifetime prediction, and design methods are comprehensively discussed herein. Finally, further research work on dynamic response characteristics of high-voltage transmission towerline system in the near future is predicted.

  4. Analysis of transmission lines loaded with pairs of coupled resonant elements and application to sensors

    Energy Technology Data Exchange (ETDEWEB)

    Naqui, J.; Su, L., E-mail: lijuan.suri.su@gmail.com; Mata, J.; Martín, F., E-mail: Ferran.Martin@uab.es

    2015-06-01

    This paper is focused on the analysis of transmission lines loaded with pairs of magnetically coupled resonators. We have considered two different structures: (i) a microstrip line loaded with pairs of stepped impedance resonators (SIRs), and (ii) a coplanar waveguide (CPW) transmission line loaded with pairs of split ring resonators (SRRs). In both cases, the line exhibits a single resonance frequency (transmission zero) if the resonators are identical (symmetric structure with regard to the line axis), and this resonance is different to the one of the line loaded with a single resonator due to inter-resonator coupling. If the structures are asymmetric, inter-resonator coupling enhances the distance between the two split resonance frequencies that arise. In spite that the considered lines and loading resonators are very different and are described by different lumped element equivalent circuit models, the phenomenology associated to the effects of coupling is exactly the same, and the resonance frequencies are given by identical expressions. The reported lumped element circuit models of both structures are validated by comparing the circuit simulations with extracted parameters with both electromagnetic simulations and experimental data. These structures can be useful for the implementation of microwave sensors based on symmetry properties. - Highlights: • Magnetic-coupling between resonant elements affects transmission properties. • Inter-resonant coupling enhances the distance of two resonant frequencies. • The structures are useful for sensors and comparators, etc.

  5. Antiretroviral treatment, viral load of mothers & perinatal HIV transmission in Mumbai, India

    Directory of Open Access Journals (Sweden)

    Swati P Ahir

    2013-01-01

    Full Text Available Background & objectives: Mother-to-child transmission (MTCT is the most significant route of HIV transmission in children below the age of 15 yr. In India, perinatal HIV transmission, even after treatment, accounts for 5.4 per cent of HIV cases. The present study was conducted to evaluate the efficacy of anti-retro viral therapy (ART or prophylactic treatment (PT to control maternal viral load in HIV positive women, and its effect on vertical HIV transmission to their infants. Methods: A total of 58 HIV positive women were enrolled at the time of delivery and their plasma samples were obtained within 24 h of delivery for estimation of viral load. Viral load analysis was completed in 38 women. Infants received single dose nevirapine within 2 h of birth and zidovudine for 6 wk. At the end of 18 month follow up, HIV positive or negative status was available in 28 infants. Results: Results revealed undetectable levels of viral load in 58.3 per cent of women with ART compared to 30.7 per cent of women with PT. No women on ART had viral load more than 10,000 copies/ml, whereas seven (26.9%, P=0.07 women receiving PT had this viral load. Median CD4 count of women on PT (483 cells/μl was high compared to the women on ART (289 cells/ μl. At the end of 18 months follow up, only two children were HIV positive, whose mothers were on PT. One had in utero transmission; infection detected within 48 h of delivery, while the other child was infected post partum as HIV was detected at six months follow up. Interpretation & conclusions: Women who received a single dose of nevirapine during delivery had higher levels of viral load than women on ART. Combination drug therapy for pregnant women is now a standard of care in most of the western countries; use of nevirapine monotherapy at the time of delivery in our settings is not effective in controlling viral load. This highlights initiation of ART in pregnant women to control their viral load and thus to inhibit

  6. Data transmission in long-range dielectric-loaded surface plasmon polariton waveguides

    DEFF Research Database (Denmark)

    Kharitonov, S.; Kiselev, R.; Kumar, Ashwani

    2014-01-01

    We demonstrate the data transmission of 10 Gbit/s on-off keying modulated 1550 nm signal through a long-range dielectric-loaded surface plasmon polariton waveguide structure with negligible signal degradation. In the experiment the bit error rate penalties do not exceed 0.6 dB over the 15 nm...

  7. Dealing with periodical loads and harmonics in operational modal analysis using time-varying transmissibility functions

    Science.gov (United States)

    Weijtjens, Wout; Lataire, John; Devriendt, Christof; Guillaume, Patrick

    2014-12-01

    Periodical loads, such as waves and rotating machinery, form a problem for operational modal analysis (OMA). In OMA only the vibrations of a structure of interest are measured and little to nothing is known about the loads causing these vibrations. Therefore, it is often assumed that all dynamics in the measured data are linked to the system of interest. Periodical loads defy this assumption as their periodical behavior is often visible within the measured vibrations. As a consequence most OMA techniques falsely associate the dynamics of the periodical load with the system of interest. Without additional information about the load, one is not able to correctly differentiate between structural dynamics and the dynamics of the load. In several applications, e.g. turbines and helicopters, it was observed that because of periodical loads one was unable to correctly identify one or multiple modes. Transmissibility based OMA (TOMA) is a completely different approach to OMA. By using transmissibility functions to estimate the structural dynamics of the system of interest, all influence of the load-spectrum can be eliminated. TOMA therefore allows to identify the modal parameters without being influenced by the presence of periodical loads, such as harmonics. One of the difficulties of TOMA is that the analyst is required to find two independent datasets, each associated with a different loading condition of the system of interest. This poses a dilemma for TOMA; how can an analyst identify two different loading conditions when little is known about the loads on the system? This paper tackles that problem by assuming that the loading conditions vary continuously over time, e.g. the changing wind directions. From this assumption TOMA is developed into a time-varying framework. This development allows TOMA to not only cope with the continuously changing loading conditions. The time-varying framework also enables the identification of the modal parameters from a single dataset

  8. Load Sharing Multiobjective Optimization Design of a Split Torque Helicopter Transmission

    Directory of Open Access Journals (Sweden)

    Chenxi Fu

    2015-01-01

    Full Text Available Split torque designs can offer significant advantages over the traditional planetary designs for helicopter transmissions. However, it has two unique properties, gap and phase differences, which result in the risk of unequal load sharing. Various methods have been proposed to eliminate the effect of gap and promote load sharing to a certain extent. In this paper, system design parameters will be optimized to change the phase difference, thereby further improving load sharing. A nonlinear dynamic model is established to measure the load sharing with dynamic mesh forces quantitatively. Afterwards, a multiobjective optimization of a reference split torque design is conducted with the promoting of load sharing property, lightweight, and safety considered as the objectives. The load sharing property, which is measured by load sharing coefficient, is evaluated under multiple operating conditions with dynamic analysis method. To solve the multiobjective model with NSGA-II, an improvement is done to overcome the problem of time consuming. Finally, a satisfied optimal solution is picked up as the final design from the Pareto optimal front, which achieves improvements in all the three objectives compared with the reference design.

  9. Using plasma viral load to guide antiretroviral therapy initiation to prevent HIV-1 transmission.

    Directory of Open Access Journals (Sweden)

    Pamela M Murnane

    Full Text Available BACKGROUND: Current WHO guidelines recommend antiretroviral therapy (ART initiation at CD4 counts ≤350 cells/µL. Increasing this threshold has been proposed, with a primary goal of reducing HIV-1 infectiousness. Because the quantity of HIV-1 in plasma is the primary predictor of HIV-1 transmission, consideration of plasma viral load in ART initiation guidelines is warranted. METHODS: Using per-sex-act infectivity estimates and cross-sectional sexual behavior data from 2,484 HIV-1 infected persons with CD4 counts >350 enrolled in a study of African heterosexual HIV-1 serodiscordant couples, we calculated the number of transmissions expected and the number potentially averted under selected scenarios for ART initiation: i CD4 count 350 while averting 40.5% of expected transmissions (ratio 2.0; treating at viral load ≥10,0000 copies/mL had a ratio of 1.5. In contrast, initiation at CD4 count <500 would require treating 41.8%, while averting 48.4% (ratio 1.1. CONCLUSION: Inclusion of viral load in ART initiation guidelines could permit targeting ART resources to HIV-1 infected persons who have a higher risk of transmitting HIV-1. Further work is needed to estimate costs and feasibility.

  10. Transmission path phase compensation for gear monitoring under fluctuating load conditions

    Science.gov (United States)

    Stander, C. J.; Heyns, P. S.

    2006-10-01

    Vibration can be monitored under fluctuating load conditions if provision is made for taking into account the fluctuation in machine speed, the response amplitude modulation caused by the change in input force, and the amplitude and phase effects on the measured response from the transmission path. Methodologies have been developed to compensate for the effects of fluctuating speed and amplitude modulation. However, this article investigates the effect of the transmission path phase. This is discussed in terms of the effect this phase has on synchronous averaging. A new approach is presented to resolve the influence that the transmission path phase has on synchronous averaging. The approach is used for the experimental data measured on a helical gear test rig. A significant improvement in the rate of convergence was obtained by adopting the new approach which compensates for the phase shifting in the measured structural response. This contrasts with conventional synchronous averaging with order tracking which does not compensate for structural response phase shifting.

  11. On transmission errors and profile modifications minimising dynamic tooth loads in multi-mesh gears

    Science.gov (United States)

    Velex, Ph.; Chapron, M.; Fakhfakh, H.; Bruyère, J.; Becquerelle, S.

    2016-09-01

    A modular three-dimensional model of multi-mesh gears is used to analyse theoretically the link between dynamic mesh excitations and transmission errors. It is demonstrated that dynamic mesh forces are mostly controlled by the local transmission errors associated with each individual mesh. A design criterion is derived which can be used to define the tooth shape modifications minimising dynamic tooth loads. The results from two examples of application on idler and planetary systems prove that the proposed theory is sound and can be applied to a variety of gear geometries. Finally, the interest and limits of using transmission errors from a single pinion-gear pair in the context of multi-mesh gears are discussed.

  12. Gain compensated symmetric loaded transmission line exhibiting bidirectional negative group delay

    Science.gov (United States)

    Bridges, Greg E.; Kandic, Miodrag

    2012-12-01

    A one-dimensional medium capable of bidirectional lossless negative group delay electromagnetic wave propagation is described. The medium is implemented as a microwave circuit comprising two symmetric resonator-loaded transmission lines, with active gain compensation and coupled through power combiners. We experimentally demonstrate the circuit is conditionally stable and is capable of lossless transmission of a finite bandwidth pulse in both directions. A measured group delay of -600 ps with a gain of 1.12 dB in both directions is achieved for a Gaussian pulse with a bandwidth of 14 MHz modulated at a frequency of 280 MHz (NGD-bandwidth-product of 0.0084). This circuit demonstrates the possibility of constructing a one-dimensional spatial void.

  13. Low-Profile Fully-Printed Multifrequency Monopoles Loaded with Complementary Metamaterial Transmission Line

    Directory of Open Access Journals (Sweden)

    Xue Li

    2015-04-01

    Full Text Available The design of a new class of multifrequency monopoles by loading a set of resonant-type complementary metamaterial transmission lines (CMTL is firstly presented. Two types of CMTL elements are comprehensively explored: the former is the epsilon negative (ENG one by loading complementary split ring resonators (CSRRs with different configurations on the signal strip, whereas the latter is the double negative (DNG one by incorporating the CSRRs and capacitive gaps. In both cases, the CMTLs are considered with different number of unit cells. By cautiously controlling the geometrical parameters of element structure, five antenna prototypes coving different communication standards (GSM, UMTS, DMB and WiMAX are designed, fabricated and measured. Numerical and experimental results illustrate that the zeroth-order resonance frequencies of the ENG and DNG monopoles are in desirable consistency. Moreover, of all operating frequencies the antennas exhibit fairly good impedance matching performances better than -10dB and quasi-omnidirectional radiation patterns.

  14. PSO for Multiobjective Economic Load Dispatch (MELD) for Minimizing Generation Cost and Transmission Losses

    Science.gov (United States)

    Jain, Narender Kumar; Nangia, Uma; Jain, Aishwary

    2016-06-01

    In this paper, multiobjective economic load dispatch (MELD) problem considering generation cost and transmission losses has been formulated using priority goal programming (PGP) technique. In this formulation, equality constraint has been considered by inclusion of penalty parameter K. It has been observed that fixing its value to 1,000 keeps the equality constraint within limits. The non-inferior set for IEEE 5, 14 and 30-bus systems has been generated by Particle Swarm Optimization (PSO) technique. The best compromise solution has been chosen as the one which gives equal percentage saving for both the objectives.

  15. Study of a conceptual nuclear energy center at Green River, Utah. Power demand, load center assessment and transmission

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.R.; Thaik, A.; Pingel, P.

    1982-02-01

    This document constitutes a segment of a feasibility study investigating the ramification of constructing a nuclear energy center in an arid western region. In this phase of the study. The projected power demands and load center locations were reviewed and assessed. Alternative transmission systems were analysed and a conceptual transmission for bulk power transportation is proposed with potential line routes. Environmental impacts of the proposed transmission were also identified.

  16. Impacts of rising air temperatures on electric transmission ampacity and peak electricity load in the United States

    Science.gov (United States)

    Bartos, Matthew; Chester, Mikhail; Johnson, Nathan; Gorman, Brandon; Eisenberg, Daniel; Linkov, Igor; Bates, Matthew

    2016-11-01

    Climate change may constrain future electricity supply adequacy by reducing electric transmission capacity and increasing electricity demand. The carrying capacity of electric power cables decreases as ambient air temperatures rise; similarly, during the summer peak period, electricity loads typically increase with hotter air temperatures due to increased air conditioning usage. As atmospheric carbon concentrations increase, higher ambient air temperatures may strain power infrastructure by simultaneously reducing transmission capacity and increasing peak electricity load. We estimate the impacts of rising ambient air temperatures on electric transmission ampacity and peak per-capita electricity load for 121 planning areas in the United States using downscaled global climate model projections. Together, these planning areas account for roughly 80% of current peak summertime load. We estimate climate-attributable capacity reductions to transmission lines by constructing thermal models of representative conductors, then forcing these models with future temperature projections to determine the percent change in rated ampacity. Next, we assess the impact of climate change on electricity load by using historical relationships between ambient temperature and utility-scale summertime peak load to estimate the extent to which climate change will incur additional peak load increases. We find that by mid-century (2040-2060), increases in ambient air temperature may reduce average summertime transmission capacity by 1.9%-5.8% relative to the 1990-2010 reference period. At the same time, peak per-capita summertime loads may rise by 4.2%-15% on average due to increases in ambient air temperature. In the absence of energy efficiency gains, demand-side management programs and transmission infrastructure upgrades, these load increases have the potential to upset current assumptions about future electricity supply adequacy.

  17. Dynamic additional loads influencing the fatigue life of gears in an electric vehicle transmission

    Directory of Open Access Journals (Sweden)

    G.Belingardi

    2014-10-01

    Full Text Available In recent years the implementation of the electric engine in the automotive industries has been increasingly marked. The speed of the electric motors is much higher than the combustion engine ones, bringing transmission gears to be subjected to high dynamic loads. For this reason the dynamic effects on fatigue life of these components have be taken into account in a more careful way respect to what is done with the usual gears. In the present work the overload effects due to both speed and meshing in a gear couple of an electric vehicle transmission have been analyzed. The electric vehicle is designed for urban people mobility and presents all the requirements to be certified as M1 vehicle (a weight less than 600 kg and a maximum speed more than 90 Km/h. To investigate the overload effects of teeth in contact, the reference gear design Standards (ISO 6336 introduce a specific multiplicative factor to the applied load called Internal Dynamic Factor (Kv. Aim of this work is to evaluate how dynamic overloads may influence the fatigue life of the above quoted gears in term of durability. To this goal, Kv values have been calculated by means of the analytical equations (ISO 6336 Methods B and C and then they have been compared with the results coming from multibody simulations, involving full rigid and rigid-flexible models.

  18. Wind-induced transmission tower foundation loads. A field study-design code comparison

    Energy Technology Data Exchange (ETDEWEB)

    Savory, E. [Department of Mechanical and Materials Engineering, University of Western Ontario, London, Ont. (Canada); Parke, G.A.R.; Disney, P.; Toy, N. [School of Engineering, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

    2008-06-15

    This paper presents a comparison between the wind-induced foundation loads measured on a type L6 transmission line tower during a field study in the UK and those computed using the UK Code of Practice for lattice tower and transmission line design (BS8100). In this work, the Code provisions have been generalised to give the wind-induced strain in each of the tower legs immediately above the foundation as a function of wind direction and wind speed at the top of the tower. The complete data set from the field monitoring has been decomposed to provide a similar formulation for comparison purposes. The analysis shows excellent agreement between the Code calculations and the measured results, within the overall accuracy of the field data. This indicates that, at least for the tower type examined here, the existing design Code provides a reliable transformation of the local wind speed at the top of the tower into tension and compression loads on the foundations. (author)

  19. Power transfer capability assessment of transmission interfaces with SVC and load shedding systems

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovsky, V. [DMCC-Engineering, Kiev (Ukraine). Inst. of Electrodynamics; Dolzhenitsa, Y. [DMCC Engineering, Kiev (Ukraine); Ushapovskiy, K. [National Power Co. Ukrenergo, Kiev (Ukraine)

    2009-07-01

    As a result of deregulation in the power industry, energy trade and markets are pushing transmission system operators to operate their systems closer to the edge of the power transfer capability. Voltage instability and inadequate reactive power support of generators is a key factor in most major outages around the world. The ideal way to control power systems is to avoid emergencies by reliable planning and secure operation of power systems. Therefore, the accurate calculation of the power transfer capability of transmission interfaces is an important task on the planning and operation stages. This paper discussed the issue of transfer capability assessment and monitoring for interfaces with static var compensator (SVC) and load shedding schemes. It also proposed a special measure, a distance to voltage instability point, to monitor transfer capability on-line. The distance may be observed by measurement of SVC output. The paper considered the problem of optimal SVC size selection and a new approach was proposed based on P-V curves analysis. The paper discussed the problem formulation and proposed approach. A case was also presented in order to demonstrate the proposed approach on the IPS Ukraine-Crimea interface. It was concluded that the proposed approach allows the optimal rating of SVC for increasing transfers capability of transmission corridors. 12 refs., 9 figs.

  20. Reliability assessment of an OVH HV power line truss transmission tower subjected to seismic loading

    Science.gov (United States)

    Winkelmann, Karol; Jakubowska, Patrycja; Soltysik, Barbara

    2017-03-01

    The study focuses on the reliability of a transmission tower OS24 ON150 + 10, an element of an OVH HV power line, under seismic loading. In order to describe the seismic force, the real-life recording of the horizontal component of the El Centro earthquake was adopted. The amplitude and the period of this excitation are assumed random, their variation is described by Weibull distribution. The possible space state of the phenomenon is given in the form of a structural response surface (RSM methodology), approximated by an ANOVA table with directional sampling (DS) points. Four design limit states are considered: stress limit criterion for a natural load combination, criterion for an accidental combination (one-sided cable snap), vertical and horizontal translation criteria. According to these cases the HLRF reliability index β is used for structural safety assessment. The RSM approach is well suited for the analysis - it is numerically efficient, not excessively time consuming, indicating a high confidence level. Given the problem conditions, the seismic excitation is shown the sufficient trigger to the loss of load-bearing capacity or stability of the tower.

  1. Parasite load in guinea pig foetus with real time PCR after maternofoetal transmission of toxoplasma gondii

    Directory of Open Access Journals (Sweden)

    Flori P.

    2003-06-01

    Full Text Available Parasite loads of different tissues were assessed in guinea pig foetus after maternal infection. Twelve female guinea pigs were infected with 100 cysts of the 76 K strain of Toxoplasma gondii by the oral route. Inoculation was performed 20 ± 5 days (G20 or 40 ± 5 days (G40 after the beginning of gestation. Gestational age was determined by progesterone assay. Maternal and foetal organ samples were taken 60 days after the beginning of gestation. Parasite loads (from placenta, amniotic fluid (AF, cord blood (CB, foetal brain, liver, lung and spleen were assessed by a real-time PCR quantification using fluorescence resonance energy transfer (FRET hybridization probes on the Light Cycler®. Congenital transmission was proven by the presence of parasites in blood or tissue samples of the foetus in 84.6% (11/13 and 100 % (16/16 of cases after inoculation on G20 and G40 , respectively. The quantitative analysis of our results after inoculation at G20 and G40 has allowed us to determinate the positive parasitic loads as a function of the origin of the sample and the period of inoculation. The parasite loads expressed as log (parasite/g were low in AF and CB samples: 1.49 ± 0.50 and 1.05 ± 0.10 at G20 and 1.21 ± 0.36 and 1.20 ± 0.42 at G40 respectively. In contrast the placenta and the different foetal tissues had higher parasite burdens: 2.89 ± 0.54 to 5.30 ± 0.51 at G20 and 2.81 ± 0.71 to 3.65 ± 0.59 at G40 . All the placentae were positive for parasites even in the two cases with no proven transmission. Real time quantitative PCR using the hybridization probe was a very sensitive and reproducible technique to study the kinetics of congenital toxoplasmosis in the guinea pig model wich is close to that of humans.

  2. Dynamic analysis of high speed gears by using loaded static transmission error

    Science.gov (United States)

    Özgüven, H. Nevzat; Houser, D. R.

    1988-08-01

    A single degree of freedom non-linear model is used for the dynamic analysis of a gear pair. Two methods are suggested and a computer program is developed for calculating the dynamic mesh and tooth forces, dynamic factors based on stresses, and dynamic transmission error from measured or calculated loaded static transmission errors. The analysis includes the effects of variable mesh stiffness and mesh damping, gear errors (pitch, profile and runout errors), profile modifications and backlash. The accuracy of the method, which includes the time variation of both mesh stiffness and damping is demonstrated with numerical examples. In the second method, which is an approximate one, the time average of the mesh stiffness is used. However, the formulation used in the approximate analysis allows for the inclusion of the excitation effect of the variable mesh stiffness. It is concluded from the comparison of the results of the two methods that the displacement excitation resulting from a variable mesh stiffness is more important than the change in system natural frequency resulting from the mesh stiffness variation. Although the theory presented is general and applicable to spur, helical and spiral bevel gears, the computer program prepared is for only spur gears.

  3. Transmission error and load distribution analysis of spur and double helical gear pairs used in a split path helicopter transmission design

    Science.gov (United States)

    Hochmann, David; Houser, Donald R.; Thomas, Jacob

    1991-05-01

    Because the reduction of gear noise in next-generation rotorcraft depends on the reduction of transmission errors, attention is presently given to the prediction of such errors and the load distributions of both a spur-gear pair and a double helical gear train used in a split-path helicopter transmission. Two cases are examined: (1) the spur gear mesh between the spur shaft and the lower spur/helical shaft, and (2) the double helical gear mesh between the lower spur/helical shaft and the output bull bear shaft.

  4. LBMR: Load-Balanced Multipath Routing for Wireless Data-Intensive Transmission in Real-Time Medical Monitoring.

    Science.gov (United States)

    Tseng, Chinyang Henry

    2016-05-31

    In wireless networks, low-power Zigbee is an excellent network solution for wireless medical monitoring systems. Medical monitoring generally involves transmission of a large amount of data and easily causes bottleneck problems. Although Zigbee's AODV mesh routing provides extensible multi-hop data transmission to extend network coverage, it originally does not, and needs to support some form of load balancing mechanism to avoid bottlenecks. To guarantee a more reliable multi-hop data transmission for life-critical medical applications, we have developed a multipath solution, called Load-Balanced Multipath Routing (LBMR) to replace Zigbee's routing mechanism. LBMR consists of three main parts: Layer Routing Construction (LRC), a Load Estimation Algorithm (LEA), and a Route Maintenance (RM) mechanism. LRC assigns nodes into different layers based on the node's distance to the medical data gateway. Nodes can have multiple next-hops delivering medical data toward the gateway. All neighboring layer-nodes exchange flow information containing current load, which is the used by the LEA to estimate future load of next-hops to the gateway. With LBMR, nodes can choose the neighbors with the least load as the next-hops and thus can achieve load balancing and avoid bottlenecks. Furthermore, RM can detect route failures in real-time and perform route redirection to ensure routing robustness. Since LRC and LEA prevent bottlenecks while RM ensures routing fault tolerance, LBMR provides a highly reliable routing service for medical monitoring. To evaluate these accomplishments, we compare LBMR with Zigbee's AODV and another multipath protocol, AOMDV. The simulation results demonstrate LBMR achieves better load balancing, less unreachable nodes, and better packet delivery ratio than either AODV or AOMDV.

  5. Failure Process and Energy Transmission for Single-Layer Reticulated Domes Under Impact Loads

    Institute of Scientific and Technical Information of China (English)

    WANG Duozhi; ZHI Xudong; FAN Feng; SHEN Shizhao

    2008-01-01

    No failure,moderate failure,severe failure,and slight failure are the four failure modes generalized observed in the dynamic response of the single-layer reticulated dome under vertical impact load on apex.TE (the time that the end of impact force) and 7F (the time that members are broken) are two key times in the failure process.Characteristics of dynamic responses at the two key times are shown in order to make the failure mechanism clear.Then three steps of energy transfer are summarized,i.e.energy applying,energy loss and energy transfer,energy consumption.Based on the three steps,energy transfer process for the failure reticulated dome under once impact is introduced.Energy transmissibility and local loss ratio are put forward firstly to obtain ELF (the energy left in the main reticulated dome) from the initial kinetic energy of impactor.Moreover,the distribution of failure modes is decided by ELF which leads to the maximum dynamic response of the reticulated dome,but not by the initial impact kinetic energy of impaetor.

  6. Quantitative Differences in Salivary Pathogen Load during Tick Transmission Underlie Strain-Specific Variation in Transmission Efficiency of Anaplasma marginale

    Science.gov (United States)

    The relative fitness of arthropod-borne pathogens within the vector can be a major determinant of pathogen prevalence within the mammalian host population. Strains of the tick-borne rickettsia Anaplasma marginale differ markedly in transmission efficiency with consequent impact on pathogen strain st...

  7. Effect of Large Scale Transmission Limitations on Renewable Energy Load Matching for Western U.S.: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Diakov, V.; Short, W.; Gilchrist, B.

    2012-06-01

    Based on the available geographically dispersed data for the Western U.S. (excluding Alaska), we analyze to what extent the geographic diversity of these resources can offset their variability. Without energy storage and assuming unlimited energy flows between regions, wind and PV can meet up to 80% of loads in Western U.S. while less than 10% of the generated power is curtailed. Limiting hourly energy flows by the aggregated transmission line carrying capacities decreases the fraction of the load that can be met with wind and PV generation to approximately 70%.

  8. Dynamic Reliability Analysis of Gear Transmission System of Wind Turbine in Consideration of Randomness of Loadings and Parameters

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2014-01-01

    Full Text Available A dynamic model of gear transmission system of wind turbine is built with consideration of randomness of loads and parameters. The dynamic response of the system is obtained using the theory of random sampling and the Runge-Kutta method. According to rain flow counting principle, the dynamic meshing forces are converted into a series of luffing fatigue load spectra. The amplitude and frequency of the equivalent stress are obtained using equivalent method of Geber quadratic curve. Moreover, the dynamic reliability model of components and system is built according to the theory of probability of cumulative fatigue damage. The system reliability with the random variation of parameters is calculated and the influence of random parameters on dynamic reliability of components is analyzed. In the end, the results of the proposed method are compared with that of Monte Carlo method. This paper can be instrumental in the design of wind turbine gear transmission system with more advantageous dynamic reliability.

  9. A compact very wideband amplifying filter based on RTD loaded composite right/left-handed transmission lines.

    Science.gov (United States)

    Abu-Marasa, Mahmoud O Mahmoud; El-Khozondar, Hala Jarallah

    2015-01-01

    The composite right/left-handed (CRLH) transmission line (TL) is presented as a general TL possessing both left-handed (LH) and right-handed (RH) natures. RH materials have both positive permittivity and positive permeability, and LH materials have both negative permittivity and negative permeability. This paper aims to design and analyze nonlinear CRLH-TL transmission line loaded with resonant tunneling diode (RTD). The main application of this design is a very wideband and compact filter that amplifies the travelling signal. We used OrCAD and ADS software to analyze the proposed circuit. CRLH-TL consists of a microstrip line which is loaded with complementary split-rings resonators (CSRRs), series gaps, and shunt inductor connected parallel to the RTD. The designed structure possess a wide band that ranges from 5 to 10.5 GHz and amplifies signal up to 50 %. The proposed design is of interest to microwave compact component designers.

  10. The Reusable Load Cell with Protection Applied for Online Monitoring of Overhead Transmission Lines Based on Fiber Bragg Grating.

    Science.gov (United States)

    Ma, Guoming; Mao, Naiqiang; Li, Yabo; Jiang, Jun; Zhou, Hongyang; Li, Chengrong

    2016-06-21

    Heavy ice coating of high-voltage overhead transmission lines may lead to conductor breakage and tower collapse causing the unexpected interrupt of power supply. The optical load cell applied in ice monitoring systems is immune to electromagnetic interference and has no need of a power supply on site. Therefore, it has become a hot research topic in China and other countries. In this paper, to solve the problem of eccentric load in measurement, we adopt the shearing structure with additional grooves to improve the strain distribution and acquire good repeatability. Then, the fiber Bragg grating (FBG) with a permanent weldable package are mounted onto the front/rear groove of the elastic element by spot welding, the direction deviation of FBGs is 90° from each other to achieve temperature compensation without an extra FBG. After that, protection parts are designed to guarantee high sensitivity for a light load condition and industrial safety under a heavy load up to 65 kN. The results of tension experiments indicate that the sensitivity and resolution of the load cell is 0.1285 pm/N and 7.782 N in the conventional measuring range (0-10 kN). Heavy load tension experiments prove that the protection structure works and the sensitivity and resolution are not changed after several high load (65 kN) cycles. In addition, the experiment shows that the resolution of the sensor is 87.79 N in the large load range, allowing the parameter to be used in heavy icing monitoring.

  11. Floating Shaft Load Sharing Method for Face Gear Split Torque Transmission System

    Directory of Open Access Journals (Sweden)

    Ruifeng Wang

    2013-04-01

    Full Text Available In this study, the equivalent gear meshing error principle was used to analysis face gear split torque dynamics modeling, the mathematical model includes stiffness of shaft supporting, position of gears, backlashes, time-varying stiffness, damping, manufacturing error, assembly error. The result shows the floating shaft can achieved load sharing, the support stiffness is an important factor, decreasing the input shaft support stiffness, load sharing performance becomes better and vibration decreases by increasing the displacement of shaft. To study effect of errors, every errors change separately while others’ ideal. Every errors affect load sharing in different way, gear 4 manufacturing error and shaft 2 assembly error affect load sharing most, load sharing cannot achieve by decreasing one error.

  12. Frequency Selective Properties of Coaxial Transmission Lines Loaded with Combined Artificial Inclusions

    Directory of Open Access Journals (Sweden)

    Francisco Falcone

    2014-01-01

    Full Text Available The properties of a modified coaxial transmission line by periodic inclusions will be discussed. The introduction of split ring resonators, conductor stubs, air gaps, and combination of these gives rise to new frequency selective properties, such as stopband or passband behavior, observable in planar as well as volumetric metamaterial structures. These results envisage new potential applications and implementation of devices in coaxial transmission line technology.

  13. Effects of inductive waves on multi-band below-cut-off transmission in waveguides loaded with dielectric metamaterials

    Directory of Open Access Journals (Sweden)

    Fang Chen

    2014-10-01

    Full Text Available Unusual backward and forward wave propagation in below cut-off waveguides loaded with dielectric metamaterials comprised of linear arrays of dielectric resonators (DRs has been investigated by using theoretical, numerical, and experimental methods. Transmission bands were shown to correspond to three lowest resonances in arrays and were analyzed by using the concepts of magneto- and electro-inductive (MI and EI waves describing the transfer of resonance excitation along the chains of coupled resonators. Equivalent circuit models (ECMs have been constructed to describe MI and EI wave propagation and to obtain the dispersion diagrams. Good agreement between the obtained data and the results of full-wave simulations, theoretical calculations, and experiments provided an opportunity to determine coupling coefficients characterizing interaction between DRs in arrays at various resonances. It was shown that ripples observed in below cut-off transmission bands are transmission resonances caused by Fabry-Perot oscillations of inductive waves at impedance mismatch at the array ends. Fitting the transmission spectra for MI/EI waves in arrays, calculated by using the Transfer Matrix Method to the spectra obtained by using full-wave simulations/measurements, allowed for determining the ECM parameters to fully characterize the DR array properties.

  14. Design and analysis of lumped resistor loaded metamaterial absorber with transmission band.

    Science.gov (United States)

    Chen, Xi; Li, Youquan; Fu, Yunqi; Yuan, Naichang

    2012-12-17

    A new type of multi-layer metamaterial (MM) absorber is represented in this paper, which behave as a dielectric slab in transmission band and act as an absorber in another lower band. The equivalent circuit model of each layer in this MM absorber has been established. The transmission line (TL) model is introduced to analysis the mechanism of electromagnetic wave traveling through this MM absorber. Both theoretical and experimental results indicate this MM absorber has a transmission band at 21GHz and an absorptive band from 5GHz to 13GHz. A good match of TL model results and measurement results verified the validity of TL model in analyzing and optimizing the performances of this kind of absorber.

  15. High-performance traveling-wave electroabsorption modulators utilizing mushroom-type waveguide and periodic transmission line loading

    Institute of Scientific and Technical Information of China (English)

    Kambiz Abedi

    2012-01-01

    For the first time,periodic loaded electrodes and mushroom-type waveguide are combined to improve the performance of traveling-wave electroabsorption modulators (TWEAMs) based on the asymmetric intra-step-barrier coupled double strained quantum well (AICD-SQW).The electrical modulation response of periodic mushroom-type TWEAM is obtained by using equivalent circuit model,and is compared with simulation result of conventional mushroom-type TWEAM counterpart.The equivalent circuit model simulation results indicate that for the exemplary modulation length of 300 μm,the mushroom-type TWEAM with periodic transmission line loading can achieve much wider bandwidth about 99.7 GHz and 43.1GHz than the conventional counterpart with about 43 GHz and 33 GHz for 35 Ω and 45 Ω terminations,respectively.

  16. Reliability of datagram transmission on Gigabit Ethernet at full link load

    CERN Document Server

    Barczyk, A; Dufey, J P; Galli, D; Jost, B; Marconi, U; Neufeld, N; Peco, G; Vagnoni, V M

    2004-01-01

    The reliability of datagram transmission over Copper Gigabit Ethernet using commodity hardware at sustained Gb/s rate is crucial for the functioning of the software trigger layers of the LHCb experiment. We aim to demonstrate that a nowadays available high-end commodity PC can be employed to achieve the required network performance, in particular to implement a sub-farm controller node. To evaluate all components ranging from the physical medium up to the operating system running on the sub-farm controllers, several issues are addressed, such as transmission error rate, packet drop in switching hardware, protocol handling on reception.

  17. Avalanche transmission and critical behaviour in load-bearing hierarchical networks

    Indian Academy of Sciences (India)

    Ajay Deep Kachhvah; Neelima Gupte

    2011-11-01

    The strength and stability properties of hierarchical load-bearing networks and their strengthened variants have been discussed in a recent work. Here, we study the avalanche time distributions on these load-bearing networks. The avalanche time distributions of the V-lattice, a unique realization of the networks, show power-law behaviour when tested with certain fractions of its trunk weights. All other avalanche distributions show Gaussian peaked behaviour. Thus the V-lattice is the critical case of the network. We discuss the implications of this result.

  18. Critical System Cascading Collapse Assessment for Determining the Sensitive Transmission Lines and Severity of Total Loading Conditions

    Directory of Open Access Journals (Sweden)

    Nur Ashida Salim

    2013-01-01

    Full Text Available This paper presents a computationally accurate technique used to determine the estimated average probability of a system cascading collapse considering the effect of hidden failure on a protection system. This includes an accurate calculation of the probability of hidden failure as it will give significant effect on the results of the estimated average probability of system cascading collapse. The estimated average probability of a system cascading collapse is then used to determine the severe loading condition contributing to a higher risk of a system cascading collapse. This information is important because it will assist the utility to determine the maximum level of increase in the system loading condition before the occurrence of critical power system cascading collapse. Furthermore, the initial tripping of sensitive transmission line contributing to a critical system cascading collapse can also be determined by using the proposed method. Based on the results obtained from this study, it was found that selecting the accurate probability of hidden failure is very important as it will affect the estimated average probability of a system cascading collapse. Comparative study has been done with other techniques to verify the effectiveness of the proposed method used in the determination of sensitive transmission lines.

  19. A Dual-Mode Bandpass Filter with Multiple Controllable Transmission-Zeros Using T-Shaped Stub-Loaded Resonators

    Directory of Open Access Journals (Sweden)

    Zh. Yao

    2014-01-01

    Full Text Available A dual-mode broadband bandpass filter (BPF with multiple controllable transmission-zeros using T-shaped stub-loaded resonators (TSSLRs is presented. Due to the symmetrical plane, the odd-even-mode theory can be adopted to characterize the BPF. The proposed filter consists of a dual-mode TSSLR and two modified feed-lines, which introduce two capacitive and inductive source-load (S-L couplings. Five controllable transmission zeros (TZs can be achieved for the high selectivity and the wide stopband because of the tunable amount of coupling capacitance and inductance. The center frequency of the proposed BPF is 5.8 GHz, with a 3 dB fraction bandwidth of 8.9%. The measured insertion and return losses are 1.75 and 28.18 dB, respectively. A compact size and second harmonic frequency suppression can be obtained by the proposed BPF with S-L couplings.

  20. Flexible Transmission Network Expansion Planning Considering Uncertain Renewable Generation and Load Demand Based on Hybrid Clustering Analysis

    Directory of Open Access Journals (Sweden)

    Yun-Hao Li

    2015-12-01

    Full Text Available This paper presents a flexible transmission network expansion planning (TNEP approach considering uncertainty. A novel hybrid clustering technique, which integrates the graph partitioning method and rough fuzzy clustering, is proposed to cope with uncertain renewable generation and load demand. The proposed clustering method is capable of recognizing the actual cluster distribution of complex datasets and providing high-quality clustering results. By clustering the hourly data for renewable generation and load demand, a multi-scenario model is proposed to consider the corresponding uncertainties in TNEP. Furthermore, due to the peak distribution characteristics of renewable generation and heavy investment in transmission, the traditional TNEP, which caters to rated renewable power output, is usually uneconomic. To improve the economic efficiency, the multi-objective optimization is incorporated into the multi-scenario TNEP model, while the curtailment of renewable generation is considered as one of the optimization objectives. The solution framework applies a modified NSGA-II algorithm to obtain a set of Pareto optimal planning schemes with different levels of investment costs and renewable generation curtailments. Numerical results on the IEEE RTS-24 system demonstrated the robustness and effectiveness of the proposed approach.

  1. Comparison of sound transmission in human ears and coupler loaded by audiometric earphones

    DEFF Research Database (Denmark)

    Ciric, Dejan; Hammershøi, Dorte

    2005-01-01

    earphones, which is related to coupling of these earphones to human ears and to the coupler. This is done by measurements of the transfer functions from input voltage of the earphone terminals to the entrance of the ear canal in two situations: open, and blocked. Similar measurements were carried out......The thresholds of hearing are usually determined using audiometric earphones. They are calibrated by means of a standardized acoustical coupler. In order to have determined thresholds independent of the earphone type, the coupler should approximate the average human ear closely. Nevertheless...... in the coupler, but since the "ear canal entrance" is not well-defined for the coupler, the mentioned measurements were done at different depths in the coupler. The sound transmission and coupling were described in terms of the pressure division at the entrance of the ear canal and the transmissions in human...

  2. Effects of Different Backpack Loads in Acceleration Transmission during Recreational Distance Walking.

    Science.gov (United States)

    Lucas-Cuevas, Angel G; Pérez-Soriano, Pedro; Bush, Michael; Crossman, Aaron; Llana, Salvador; Cortell-Tormo, Juan M; Pérez-Turpin, José A

    2013-01-01

    It is well established nowadays the benefits that physical activity can have on the health of individuals. Walking is considered a fundamental method of movement and using a backpack is a common and economical manner of carrying load weight. Nevertheless, the shock wave produced by the impact forces when carrying a backpack can have detrimental effects on health status. Therefore, the aim of this study was to investigate differences in the accelerations placed on males and females whilst carrying different loads when walking. Twenty nine sports science students (16 males and 13 females) participated in the study under 3 different conditions: no weight, 10% and 20% body weight (BW) added in a backpack. Accelerometers were attached to the right shank and the centre of the forehead. Results showed that males have lower accelerations than females both in the head (2.62 ± 0.43G compared to 2.83 + 0.47G) and shank (1.37 ± 0.14G compared to 1.52 ± 0.15G; pbackpack condition (p>0.05). The body acts as a natural shock absorber, reducing the amount of force that transmits through the body between the foot (impact point) and head. Anthropometric and body mass distribution differences between males and females may result in women receiving greater impact acceleration compared to men when the same load is carried.

  3. Adaptive Transmission Opportunity Scheme Based on Delay Bound and Network Load in IEEE 802.11e Wireless LANs

    Directory of Open Access Journals (Sweden)

    S. Kim

    2013-08-01

    Full Text Available The IEEE 802.11e EDCA (Enhanced Distributed Channel Access is able to provide QoS (Quality of Service by adjusting the transmission opportunities (TXOPs, which control the period to access the medium. The EDCA has a fairness problem among competing stations, which support multimedia applications with different delay bounds. In this paper, we propose a simple and effective scheme for alleviating the fairness problem. The proposed scheme dynamically allocates the TXOP value based on the delay bounds of the data packets in a queue and the traffic load of network. Performance of the proposed scheme is investigated by simulation. Our results show that compared to conventional scheme, the proposed scheme significantly improves network performance, and achieves a high degree of fairness among stations with different multimedia applications.

  4. Experimental and theoretical verification of focusing in a large, periodically loaded transmission line negative refractive index metamaterial.

    Science.gov (United States)

    Iyer, Ashwin; Kremer, Peter; Eleftheriades, George

    2003-04-07

    We have previously shown that a new class of Negative Refractive Index (NRI) metamaterials can be constructed by periodically loading a host transmission line medium with inductors and capacitors in a dual (high-pass) configuration. A small planar NRI lens interfaced with a Positive Refractive Index (PRI) parallel-plate waveguide recently succeeded in demonstrating focusing of cylindrical waves. In this paper, we present theoretical and experimental data describing the focusing and dispersion characteristics of a significantly improved device that exhibits minimal edge effects, a larger NRI region permitting precise extraction of dispersion data, and a PRI region consisting of a microstrip grid, over which the fields may be observed. The experimentally obtained dispersion data exhibits excellent agreement with the theory predicted by periodic analysis, and depicts an extremely broadband region from 960MHz to 2.5GHz over which the refractive index remains negative. At the frequency at which the theory predicts a relative refractive index of -1, the measured field distribution shows a focal spot with a maximum beam width under one-half of a guide wavelength. These results are compared with field distributions obtained through mathematical simulations based on the plane-wave expansion technique, and exhibit a qualitative correspondence. The success of this experiment attests to the repeatability of the original experiment and affirms the viability of the transmission line approach to the design of NRI metamaterials.

  5. Evidence against proteoglycan mediated collagen fibril load transmission and dynamic viscoelasticity in tendon.

    Science.gov (United States)

    Fessel, Gion; Snedeker, Jess G

    2009-10-01

    The glycosaminoglycan (GAG) dermatan sulfate and chondroitin sulfate side-chains of small leucine-rich proteoglycans have been increasingly posited to act as molecular cross links between adjacent collagen fibrils and to directly contribute to tendon elasticity. GAGs have also been implicated in tendon viscoelasticity, supposedly affecting frictional loss during elongation or fluid flow through the extra cellular matrix. The current study sought to systematically test these theories of tendon structure-function by investigating the mechanical repercussions of enzymatic depletion of GAG complexes by chondroitinase ABC in a reproducible tendon structure-function model (rat tail tendon fascicles). The extent of GAG removal (at least 93%) was verified by relevant spectrophotometric assays and transmission electron microscopy. Dynamic viscoelastic tensile tests on GAG depleted rat tail tendon fascicle were not mechanically different from controls in storage modulus (elastic behavior) over a wide range of strain-rates (0.05, 0.5, and 5% change in length per second) in either the linear or nonlinear regions of the material curve. Loss modulus (viscoelastic behavior) was only affected in the nonlinear region at the highest strain-rate, and even this effect was marginal (19% increased loss modulus, p=0.035). Thus glycosaminoglycan chains of small leucine-rich proteoglycans do not appear to mediate dynamic elastic behavior nor do they appear to regulate the dynamic viscoelastic properties in rat tail tendon fascicles.

  6. Effect of cell and microvillus mechanics on the transmission of applied loads to single bonds in dynamic force spectroscopy.

    Science.gov (United States)

    Gupta, V K; Eggleton, C D

    2011-07-01

    Receptor-ligand interactions that mediate cellular adhesion are often subjected to forces that regulate their detachment via modulating off-rates. Although the dynamics of detachment is primarily controlled by the physical chemistry of adhesion molecules, cellular features such as cell deformability and microvillus viscoelasticity have been shown to affect the rolling velocity of leukocytes in vitro through experiments and simulation. In this work, we demonstrate via various micromechanical models of two cells adhered by a single (intramolecular) bond that cell deformability and microvillus viscoelasticity modulate transmission of an applied external load to an intramolecular bond, and thus the dynamics of detachment. Specifically, it is demonstrated that the intermolecular bond force is not equivalent to the instantaneous applied force and that the instantaneous bond force decreases with cellular and microvillus compliance. As cellular compliance increases, not only does the time lag between the applied load and the bond force increase, an initial response time is observed during which cell deformation is observed without transfer of force to the bond. It is further demonstrated that following tether formation the instantaneous intramoleular bond force increases linearly at a rate dependent on microvillus viscosity. Monte Carlo simulations with fixed kinetic parameters predict that both cell and microvillus compliance increase the average rupture time, although the average rupture force based on bond length remains nearly unchanged.

  7. Polarized light transmission in ferrofluids loaded with carbon nanotubes in the presence of a uniform magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Vales-Pinzón, C., E-mail: cvales@mda.cinvestav.mx [Applied Physics Department, CINVESTAV-Unidad Mérida, Antigua carretera a Progreso km 6, A.P. 73, Cordemex, Mérida Yucatán 97310 (Mexico); Alvarado-Gil, J.J. [Applied Physics Department, CINVESTAV-Unidad Mérida, Antigua carretera a Progreso km 6, A.P. 73, Cordemex, Mérida Yucatán 97310 (Mexico); Medina-Esquivel, R. [Facultad de Ingeniería-UADY, Av. Industrias no Contaminantes por Periférico Norte, A.P. 150, Cordemex, Mérida, Yucatán (Mexico); Martínez-Torres, P. [Department of Mechanical Engineering, University of California, Riverside, 900 University Ave., Riverside, CA 92521 (United States)

    2014-11-15

    Magneto-optic phenomena in ferrofluids have been shown to be related to the formation of chain structures, due to the arrangement of the ferromagnetic particles, induced by an applied magnetic field. In this work, the effects on transmission of polarized light due to anisotropic effects induced by an external magnetic field in ferrofluids with carbon nanotubes are studied. The time response of the system presents two well defined stages, in the first one, which is very short, the fluid behaves as a polarizer. In contrast in the second stage, the effects of light transmission dominate. In this stage the transmitted light intensity grows with time and after a long time reaches a constant stable value. It is shown that these phenomena depend on the carbon nanotubes concentration as well as on the strength of the applied magnetic field. Using a simple model that considers a chain-like structure formation, it is possible to determine the rate of agglomeration of the formed structures and the attenuation coefficient of the transmitted light. The formation of nanostructures leads to variation in the transmitted light, depending on the polarization of the incident light. These magnetic nanostructures can find numerous applications in nanotechnology, optical devices and medicine. - Highlights: • Carbon nanotubes in ferrofluids favor the formation of chain-like structures. • In the presence of a magnetic field ferrofluids loaded with CNT behaves as a polarizer. • Transmitted light increases when samples are under a magnetic field then stabilizes. • Attenuation time for transmitted light and agglomeration parameters were studied.

  8. A Flexible Load Control Strategy for Distribution Network to Reduce the Line Losses and to Eliminate the Transmission Congestion

    National Research Council Canada - National Science Library

    2017-01-01

    .... Air conditioners (ACs) account for a great proportion of all loads. In this paper, the model of dispatching AC loads in the regional power grid is constructed, and the direct load control (DLC...

  9. A Load-balance and EEDF based strategy for reducing transmission delay of VoIP services in IEEE 802.16e system

    Institute of Scientific and Technical Information of China (English)

    Wang Lilei; Xu Huimin

    2009-01-01

    To decrease the transmission delay of uplink voice over IP (VoIP) services in IEEE 802.16e system, a novel strategy which includes a load-balance algorithm and an extended earliest deadline first (EEDF) scheduling algorithm is proposed. Subsequently, this paper analyzes the performance of the proposed strategy in terms of transmission delay of VoIP services, system capacity, throughput and compatibility with IEEE 802.16e standard. Finally, simulation experiments are carried out to verify the improvement of the proposed strategy. The simulation results match well with the theoretical analysis and show that the proposed strategy reduces the transmission delay of uplink VoIP services and improves the capacity and throughput. These improvements are remarkable especially when the load of system is heavy.

  10. Capacidad de carga de las transmisiones por tornillo sinfín y corona. // Load capacity of worm gears transmissions.

    Directory of Open Access Journals (Sweden)

    G. Rivero Llerena

    2003-01-01

    Full Text Available El uso de los reductores de velocidad comenzó a principios del siglo xx, su extensa difusión en el mundo actual permiteadquirirlos como unidades ensambladas a un costo relativamente bajo para la calidad del producto ofertado. Losantecedentes de este trabajo están en las investigaciones realizadas desde hace más de tres décadas en el ISPJAE. Lacreación de tecnologías propias sobre la base de estas investigaciones ha permitido la producción de reductores develocidad por tornillo sinfín con índices de calidad comparables con los índices de los reductores foráneos. El método dereconversión de reductores de velocidad que han quedado fuera de servicio, es utilizado en Cuba con resultadossatisfactorios a partir de la utilización de las carcasas originales. El presente trabajo pretende destacar la influencia de loserrores de contacto en la capacidad de carga de la transmisión por tornillo sinfín. Se brinda en esta ocasión, unprocedimiento para el cálculo automatizado de la superficie activa del diente de la rueda y se ofrece una expresión decálculo propia que permite pronosticar la capacidad de carga de la transmisión, a partir de la huella de contacto, encorrespondencia con los requisitos de contacto para un grado de precisión dado.Palabras claves: Capacidad de carga, huella de contacto, tornillo sinfín._____________________________________________________________________________Abstract.The use of worm gears transmissions started at the beginning of the 20th century and its wide spread use allow to purchaseas join units with low cost according to the product quality. Investigations that for more than thirty years took place at theISPJAE are the bases of this study. The Cuban technologies have permitted to produce worm gears with a comparablequality as foreign ones. The reconversion method for worm gears out of service is used in Cuba, and satisfactory results areobtained. In this paper are exposed the contact errors influence

  11. Study on a discal TEM-TE{sub 11} mode converter loaded high-efficiency magnetically insulated transmission line oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaoping, E-mail: zhangxiaoping@nudt.edu.cn; Yuan, Chengwei; Li, Yangmei; Zhang, Jiande; Zhang, Qiang [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2015-12-15

    An integrative high power microwave device is proposed, which consists of a high-efficiency L-band Magnetically Insulated Transmission Line Oscillator (MILO) and a discal TEM–TE{sub 11} mode converter. The MILO with a shrunken load composed of a step-like cathode and a ladder-like beam collector can generate a 1.58 GHz, 5.7 GW microwave with the efficiency of 20.8% at the diode voltage of 560 kV in simulation. The discal converter utilizes a pair of sectorial two-double radial waveguides and a pair of sectorial cross section waveguides to adjust the phase-difference and realizes the mode conversion in a length of less than half wavelength at 1.58 GHz. In the preliminary experiment, the proposed device generates over 2 GW, 1.575 GHz microwave with the pulse duration of over 50 ns in a 420 kV diode voltage; the corresponding efficiency is 14.9%; the radiation pattern is the ideal TE{sub 11} mode.

  12. 美国输电线路风荷载计算介绍%Introduction of Wind Load Computation of Transmission Line in ASCE74-2009

    Institute of Scientific and Technical Information of China (English)

    王振华

    2012-01-01

    了解《美国输电线路结构荷载指南》( ASCE74-2009)对从事涉外工程和提高工程师设计水平都有着重要意义.风荷载是输电线路设计的控制荷载,了解ASCE74-2009风荷载计算方法非常有必要.本文介绍了ASCE74-2009输电线路风荷载的计算方法,并对基本风速、风压高度变化系数、体型系数、风荷载调整系数、地形影响因子和斜向风荷载计算方法及其计算参数进行了说明.%It is very important to comprehend 《 Guidelines for electrical transmission line structural loading》 (ASCE74-2009) for overseas projects and improve the design level of engineer. Wind load is the control load for transmission line, so it is necessary to master wind load computation method of ASCE74-2009. Wind load computation formulas for transmission line of ASCE74-2009 are introduced in this paper. The computation parameters of basic wind speed, height variation factor of wind pressure, shape factor, wind load factor, topographic factor and yawed wind load computation method are illustrated in detail.

  13. 0.48Tb/s (12x40Gb/s) WDM transmission and high-quality thermo-optic switching in dielectric loaded plasmonics

    DEFF Research Database (Denmark)

    Kalavrouziotis, Dimitrios; Papaioannou, S.; Giannoulis, Giannis;

    2012-01-01

    through BER measurements by exploiting the heterointegration of a 60 mu m-long straight DLSPPW on a Silicon-on-Insulator waveguide platform, showing error-free performance for six out of the twelve channels. High-quality thermo-optic tuning has been achieved by utilizing Cycloaliphatic......We demonstrate Wavelength Division Multiplexed (WDM)-enabled transmission of 480Gb/s aggregate data traffic (12x40Gb/s) as well as high-quality 1x2 thermo-optic tuning in Dielectric-Loaded Surface Plasmon Polariton Waveguides (DLSPPWs). The WDM transmission characteristics have been verified......-Acrylate-Polymer as an efficient thermo-optic polymer loading employed in a dual-resonator DLSPPW switching structure, yielding a 9nm wavelength shift and extinction ratio values higher than 10dB at both output ports when heated to 90 degrees C. (C)2012 Optical Society of America...

  14. Power flow between a plasma-opening switch and a load separated by a high-inductance magnetically insulated transmission line

    Science.gov (United States)

    Swanekamp, S. B.; Grossmann, J. M.; Ottinger, P. F.; Commisso, R. J.; Goyer, J. R.

    1994-09-01

    Results are presented from particle-in-cell simulations of the electron flow launched from a plasma opening switch (POS) into a magnetically insulated transmission line (MITL) as the POS opens. The opening process of the POS is treated by removing plasma from a fixed anode-cathode gap with an opening time of tau(sub rise). To be similar to opening switch experiments at Physics International, the simulations were performed with the same inductance L(sub MITL) between the POS and load. When L(sub MITL)/tau(sub rise) is large compared to the POS flow impedance, this inductance effectively isolates the POS from the load during the opening process and the POS voltage is insensitive to changes in the load impedance. Analysis and simulations show that the peak load power is maximized when the load impedance is equal to the POS flow impedance. In contrast to previous theories and simulations of magnetically insulated flows, a large amount of electron flow in the MITL is concentrated near the anode. This is a result of the high effective impedance imposed on the POS by the inductive load which causes a significant electron current loss in the POS. As a result, many electrons lose insulation on the load side of the POS gap and those that do flow into the MITL have been accelerated to nearly the full POS potential. Electrons then E cross B drift on equipotential lines close to the anode as they enter the MITL and flow toward the load. Current losses in the MITL are observed due to the proximity of the electron flow to the anode. Some electrons flow from the MITL directly into the load and are registered as load current while others E cross B drift back toward the POS along the cathode surface. This is possible because the electron flow launched into the MITL from the POS is large enough to cause sufficient positive image charges on the cathode so that the electric field points out of the cathode surface.

  15. RF design and tests on a broadband, high-power coaxial quadrature hybrid applicable to ITER ICRF transmission line system for load-resilient operations

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hae Jin, E-mail: haejin@nfri.re.kr [National Fusion Research Institute, Daejeon (Korea, Republic of); Wang, Son Jong; Park, Byoung Ho; Kwak, Jong-Gu [National Fusion Research Institute, Daejeon (Korea, Republic of); Hillairet, Julien [CEA/IRFM, Saint-lez-Durance (France); Choi, Jin Joo [Kwangwoon University, Seoul (Korea, Republic of)

    2015-10-15

    Highlights: • Amplitude balanced 3 dB coaxial hybrid splitter has been designed and rf tested. • The proposed hybrid is applicable to ITER ICRF transmission line for load resilience. • Two-section, broadband coaxial hybrid can be tunable by changing dielectric insulator. - Abstract: RF design and network analyzer tests of broadband, amplitude-balanced coaxial hybrid junctions are presented. We have designed two 3 dB hybrid splitters with 9 and 12 in. coaxial transmission lines applicable to ITER ICRF for load-resilient operations using ANSYS HFSS. Amplitude-balanced broadband responses were obtained with the combination of impedance reductions of longitudinal and transverse branches in unequal proportion, length change of 50 Ω lines and diameter change of high impedance lines connected transversely to the T-section of the hybrid splitter, respectively. We have fabricated and RF tested the 9 in. coaxial hybrid coupler. We obtained an excellent coupling flatness of −3.2 ± 0.2 dB, phase difference of 4 degrees and return loss of 16 dB in 40–55 MHz. The measured data of 9 in. hybrid splitter is highly consistent with HFSS simulations. We found that the proposed 3 dB hybrid splitter can be tunable with amplitude-balanced, broadband response by changing dielectric insulators to keep the inner and outer conductors of coaxial line apart. The proposed 3 dB hybrid splitter can be utilized for load-resilient operations in a wide range of antenna load variations due to mode transitions or edge localized modes (ELMs) in fusion plasmas.

  16. 中印输电线路规范风荷载比较%Comparative Study on Wind Loads of Transmission Line between Indian Codes and Chinese Codes

    Institute of Scientific and Technical Information of China (English)

    曾德森; 徐彬; 覃伟平; 舒爱强

    2012-01-01

    With increasing requirements for designing overseas projects, it is necessary to understand and master foreign engineering codes and differences between those codes and Chinese codes. Based on practical engineering projects, this paper presents a comparative study on the wind load calculations of an overhead transmission line by Indian IS 802 and Chinese GB 50545-2010 for the power transmission line project, respectively. The study suggests that there are some differences in the wind load return period, average wind speed time interval, drag coefficient, and calculated loads on the conductor and steel tower between Indian codes and Chinese codes.%面对越来越多的国外工程设计的需求,了解、熟悉并掌握国外规范及其与国内规范的异同,对于在国外工程中更好地采用国外规范进行设计是很有必要的.从实际工程出发,对印度输电线路规范IS 802和中国输电线路规范GB 50545-2010的风荷载计算进行分析和比较.结果表明,中印规范在风荷载重现期、平均时距、风载体型系数、风振系数以及线路和杆塔风荷载计算值上都有些差别.

  17. 3-D finite element analysis of the influence of synovial condition in sacroiliac joint on the load transmission in human pelvic system.

    Science.gov (United States)

    Shi, Dufang; Wang, Fang; Wang, Dongmei; Li, Xiaoqin; Wang, Qiugen

    2014-06-01

    The anterior part of the sacroiliac joint (SIJ) is a synovial joint, with little gliding and rotary movement between the contact surfaces of SIJ during locomotion. Due to its complex structure, especially when considering the surrounding ligaments, it is difficult to construct an accurate three-dimensional (3-D) finite element model for the human pelvis. Most of the pelvic models in the previous studies were simplified with either SIJ fusing together or without the sacral bone. However, the influence of those simplifications on the load transmission in human pelvis has not been studied, so the reliability of those studies remains unclear. In this study, two 3-D pelvic models were constructed: an SIJ fusing model and an SIJ contacting model. In the SIJ fusing model, the SIJ interfaces were fused together. In the SIJ contacting model, the SIJ interfaces were just in contact with each other without fusion. Compared with the SIJ contacting model, the SIJ fusing model have smaller movements in the SIJ. The stress distribution area in the SIJ fusing model on sacroiliac cartilages was also different. Those differences contributed to the decline of tensile force in the SIJ surrounding ligaments and the re-distribution of stress in the pelvic bones. In addition, the SIJ fusing model was far less sensitive to the increase in modulus of the sacroiliac cartilages, and decrease in stiffness of the ligaments surrounding the SIJ. The presence of synovia in the SIJ had greater influence on the load transmission in the human pelvic system. Therefore, the effect of the presence of synovia should not be neglected when the biomechanical behavior of human pelvis is being studied, especially for those studies related to clinical applications.

  18. SOUND TRANSMISSION LOSS OF A DOUBLE-LEAF SOLID-MICROPERFORATED PARTITION UNDER NORMAL INCIDENCE OF ACOUSTIC LOADING

    Directory of Open Access Journals (Sweden)

    Ahmad Yusuf Ismail

    2011-12-01

    Full Text Available 0 0 1 332 1894 International Islamic University 15 4 2222 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Times New Roman";} The micro-perforated panel (MPP is recently well-known as an alternative ‘green‘ sound absorber replacing the conventional porous materials. Constructed from a solid panel which provides a non-abrassive structure and also an optically attractive surface, there gives a feasibility to implement such a panel inside a vehicle cabin. This paper is the preliminary study to investigate the sound transmission loss (TL of a solid panel coupled with a micro-perforated panel to form a doube-leaf partition which is already known as a lightweigth stucture for noise insulation in vehicles and buildings. The mathematical model for the TL subjected to normal incidence of acoustic excitation is derived. The results show that its performance substantially improves at the troublesome frequency of mass-air-mass resonance which occurs in the conventional double-leaf solid partition. This is important particularly for the noise source predominant at low frequencies. This can also be controlled by tuning the hole size and number as well as the air gap between the panels.  ABSTRAK: Panel bertebuk mikro (micro-perforated panel (MPP kebelakangan ini dikenali sebagai alternatif penyerap bunyi yang mesra alam menggantikan bahan berliang lazim. Dibina daripada satu panel padu yang memberikan satu struktur tak lelas dan juga satu permukaan yang menarik, ia memberikan kemungkinan penggunaan panel tersebut di dalam kabin kenderaan. Tesis ini merupakan kajian permulaan dalam mengkaji hilang pancaran bunyi

  19. Efficacy and safety of telbivudine in preventing mother-to-infant transmission of HBV in pregnant women with high HBV DNA load

    Directory of Open Access Journals (Sweden)

    SUN Weihui

    2013-08-01

    Full Text Available ObjectiveTo evaluate the efficacy and safety of telbivudine given from the 12th week of gestation in preventing mother-to-infant transmission of hepatitis B virus (HBV in pregnant women with high HBV DNA load. MethodsEighty pregnant women (at 12 weeks of gestation with chronic hepatitis B, who had a HBV DNA load higher than 1.0×107 copies/ml, were enrolled. The patients were divided into two groups according to their personal preferences: treatment group (n=38 and control group (n=42. The treatment group received oral telbivudine (600 mg once daily until 12 weeks after delivery and was administered compound glycyrrhizin for liver protection, while the control group was given compound glycyrrhizin for liver protection alone. All infants in both groups were vaccinated with hepatitis B immunoglobulin (200 IU and HBV vaccine (20 μg after birth. The mother-to-infant transmission of HBV was indicated by the presence of HBsAg and HBV DNA in infants at 7 months after birth. The HBV DNA levels in these women were measured, and the positive rate of HBsAg in infants was determined. The difference in positive rate of HBsAg was analyzed by chi-square test; the between-group comparison was analyzed by group t(t′-test, and the before-after comparison was analyzed by paired t-test. ResultsThe treatment group showed significantly decreased HBV DNA and alanine aminotransferase levels before delivery. The HBV DNA load of treatment group dropped rapidly after 2 weeks of treatment and then decreased slowly until delivery. The treatment group had significantly decreased HBV DNA levels beforedelivery and at 12 weeks after delivery (t=29.15, P<0.01; t=40.06, P<0.01, but the control group showed no significant changes (P>0.05. The treatment group had significantly lower HBV DNA levels than the control group before delivery and at 12 weeks after delivery (P<0.01. No infants in the treatment group were HBV-positive, versus a positive rate of 14.3% in the

  20. 20 Gb/s WDM-OFDM-PON over 20-km single fiber uplink transmission using optical millimeter-wave signal seeding with rate adaptive bit-power loading

    Science.gov (United States)

    Kartiwa, Iwa; Jung, Sang-Min; Hong, Moon-Ki; Han, Sang-Kook

    2013-06-01

    We experimentally demonstrate the use of millimeter-wave signal generation by optical carrier suppression (OCS) method using single-drive Mach-Zehnder modulator as a light sources seed for 20 Gb/s WDM-OFDM-PON in 20-km single fiber loopback transmission based on cost-effective RSOA modulation. Practical discrete rate adaptive bit loading algorithm was employed in this colorless ONU system to maximize the achievable bit rate for an average bit error rate (BER) below 2 × 10-3.

  1. 脊背型介质加载表面等离子体波导传输特性研究%Research on waveguide transmission characteristics of spine type medium load surface plasmon

    Institute of Scientific and Technical Information of China (English)

    郑洪全; 宁海春

    2016-01-01

    In order to reduce the transmission loss, strengthen the medium loaded plasma waveguide mode field constraint and optimize the plasma waveguide transmission performance, a further research on waveguide transmission characteristics of the dielectric loaded surface plasmon was studied. A waveguide with spine type medium load plasma was designed and the relationship between the geometric parameters and the geometrical parameters of the waveguide in the mode field distribution and its transmission parameters were studied. The simulation results show that the electric field component of the base mode is mainly distributed in the metal/dielectric layer 1 interface. As a result, the transmission characteristic of the model changes with the variations of the geometrical parameters of waveguide. Hence, the field can be effectively controlled by shifting the geometrical parameters of the waveguide and localization can be enhanced obviously.%为降低传输过程中的损耗,加强介质加载等离子体波导的模式场约束,并且优化等离子体波导的传输性能,对基于介质加载的表面等离子体波导的传输特性做了进一步的研究,设计了一种脊背型介质加载等离子体波导,并对其模式场分布及其传输参数随波导中的几何参数与电磁参数的变化关系做了相应的研究。仿真结果得出:基模的电场分量主要分布在该结构的金属/介质层1界面。该模式的传输特性,随着该波导的几何参数的变化而发生相应改变,因而可以通过改变这种结构的几何参数,对场实现有效控制,使其局域性明显增强。

  2. Data Transmission and Thermo-Optic Tuning Performance of Dielectric-Loaded Plasmonic Structures Hetero-Integrated on a Silicon Chip

    DEFF Research Database (Denmark)

    Giannoulis, G.; Kalavrouziotis, D.; Apostolopoulos, D.;

    2012-01-01

    We demonstrate experimental evidence of the data capture and the low-energy thermo-optic tuning credentials of dielectric-loaded plasmonic structures integrated on a silicon chip. We show 7-nm thermo-optical tuning of a plasmonic racetrack-resonator with less than 3.3 mW required electrical power...

  3. Study on the Mechanism of Meme Transmission in C-E Translation of Cultural-loaded Words%论文化负载词英译的模因传播机制

    Institute of Scientific and Technical Information of China (English)

    王琴

    2015-01-01

    Memes are the basic elements and the replicators of culture, which are indispensable in the process of culture evolution. Culture-loaded words’appropriate translation largely determines whether the main contents of source text can be transmitted and whether the culture information transmission and communication can be achieved. The C-E translation of culture-loaded words makes the cultural memes in them get diffused in target language. This paper studies the mechanism of meme transmission in the C-E translation of Culture-loaded words on the basis of memes, with their own special features and laws, achieving the conclusion that different translational strategies will be adopted at different stages of cultural exchange.%模因作为文化重要组成部分且文化复制因子,在文化进化过程中不可或缺。文化负载词翻译的恰当与否直接关系到原作品意旨能否传递,也关系到其中文化信息的传递和文化交流的成功与否。文化负载词的英译是使凝结在汉语词汇中的文化模因在译入语中传播。该文根据模因作为复制因子具备其自身的发展规律和特点分析文化负载词英译过程中的模因传播机制,总结出文化交流的不同阶段文化负载词的翻译策略的选用。

  4. Characteristics of forced torsional vibration and dynamic load for vehicle multistage planetary transmission%车辆多级行星传动系统强迫扭转振动与动载特性

    Institute of Scientific and Technical Information of China (English)

    蔡仲昌; 刘辉; 项昌乐; 张喜清; 王明正

    2012-01-01

    A model was built for the forced torsional vibration excited by the dynamic torque of the engine in the vehicle multistage planetary transmission using the lumped parameter method,and the differential equations were derived by the Lagrangian equation and solved.The amplitude characteristics of the different parts in the same gear shift were analyzed,and their vibration behaviors were revealed.The vibrations of the planetary gear under different gear shifts were investigated,and the difference between the torsional vibrations of the planetary gear under load state and no-load state were obtained.The fluctuation of the meshing force of the planetary gear and the dynamic load coefficient were calculated,providing a basis for the design and the dynamic analysis of the multistage planetary transmission.%针对某车辆行星传动系统,以发动机动态转矩为激励,采用集中参数法建立纯扭转强迫振动模型,利用拉格朗日方程建立系统微分方程并进行求解。分析了各部件在同一档位的振幅特性,得出不同部件的振动特点。研究了不同档位下行星排的振动,得出行星排在空载与受载时扭振的差异。最后对行星排啮合力波动量和动载荷系数进行计算,为行星传动系统设计和动态分析提供了依据。

  5. Study on the Influence of System Errors of Planetary Transmission on Load Sharing%行星传动系统误差对载荷均布的影响研究

    Institute of Scientific and Technical Information of China (English)

    汤鱼; 常山; 宿吉鹏; 王志强

    2011-01-01

    根据齿轮传动中各种系统误差,建立了2K-H行星传动系统中各构件的运动学方程,进一步得到系统弹性动力学微分方程,建立系统动力学模型,推导动力学系统的总体刚度矩阵,建立行星轮上载荷与各种系统误差的关系式,分析了各种位置误差对行星轮上载荷分配的影响状况,计算了各行星轮上的均载系数.%Basing on the system errors, the kinematics equations are found for the component in the 2K-H planetary transmission system, the elasticity dynamics differential equation and dynamics model are gained. Systemic total stiffness matrix is computed and function relation between system errors and planet gear load are found. The influence is analyzed of position errors to planet gear load sharing, and the load sharing coefficients of each planet gear are calculated.

  6. Nonlinear magnetoinductive transmission lines

    CERN Document Server

    Lazarides, Nikos; Tsironis, G P

    2011-01-01

    Power transmission in one-dimensional nonlinear magnetic metamaterials driven at one end is investigated numerically and analytically in a wide frequency range. The nonlinear magnetic metamaterials are composed of varactor-loaded split-ring resonators which are coupled magnetically through their mutual inductances, forming thus a magnetoiductive transmission line. In the linear limit, significant power transmission along the array only appears for frequencies inside the linear magnetoinductive wave band. We present analytical, closed form solutions for the magnetoinductive waves transmitting the power in this regime, and their discrete frequency dispersion. When nonlinearity is important, more frequency bands with significant power transmission along the array may appear. In the equivalent circuit picture, the nonlinear magnetoiductive transmission line driven at one end by a relatively weak electromotive force, can be modeled by coupled resistive-inductive-capacitive (RLC) circuits with voltage-dependent cap...

  7. Design of big torque and heavy load transmission gears in right angle milling head%大扭矩、重载荷直角铣头传动齿轮设计

    Institute of Scientific and Technical Information of China (English)

    杨春波; 陆喜军; 刘银锋; 韩建中

    2014-01-01

    This article introduce the design process of the pair spiral bevel gears which are the core components of big torque and heavy load right angle mil ing head used to transfer power. Inside, it contains determination of bevel gear design parameter , the choice of material, design of manufacturing and heat treatment technology and checking calculation of bevel gear design parameter, etc. Through the design of big torque and heavy load transmission gears in right angle mil ing head, provides reference of design and study on other mil ing head components.%介绍大扭矩、重载直角铣头关键核心组件;传递动力的一组螺旋圆锥齿轮的设计过程,其中,包括圆锥齿轮的设计参数的确定、制造材料的选择;加工及热处理等工艺方法的制定;以及圆锥齿轮设计参数的校核计算等。通过大扭矩、重载直角铣头传动齿轮的设计。为其它铣头组件的设计、研究以及使用提供了一定的参考。

  8. Dynamic Load Calculation and Statistical Analysis of Gear Transmission System of Wind Turbine under Stochastic Wind Loading%随机风作用下风力发电机齿轮传动系统动载荷计算及统计分析

    Institute of Scientific and Technical Information of China (English)

    徐芳; 周志刚

    2016-01-01

    针对风力发电机齿轮传动系统在随机风作用下失效率高的问题,在模拟真实风速的基础上,建立考虑外部随机风载及内部齿轮时变啮合刚度、轴承时变刚度及综合传递误差等激励因素的风力发电机齿轮传动系统齿轮轴承耦合动力学模型,通过对动力学模型进行仿真计算,得到各齿轮副的动态啮合力和各支承轴承的动态接触力。结合有限单元法和赫兹接触理论,得到关键零部件的应力时间历程,采用雨流计数法对应力时间历程进行统计分析,得到传动系统各关键零部件承受载荷的应力谱及概率分布函数。研究结果为风力发电机齿轮传动系统的动态可靠性分析和疲劳寿命预测奠定基础。%Aiming at the problems of high failure rate of wind turbines gear transmission system under the stochastic wind speed conditions,a dynamics model of gear transmission system coupled with bearing of wind turbine was established on the basis of simulating real wind speed,and the exter-nal random wind load and internal excitations such as time-varying mesh stiffness of gear pair,time-varying stiffness of rolling element bearings and integrated transmission errors were considered in the model.Numerical method was used to simulate the dynamics model,the dynamic meshing forces of each gear pair as well as the dynamic contact forces of each bearing were obtained.Then,the stress spectrum and the probability distribution function of the loads acting on the key parts of transmission system were obtained by statistic the stress-time history curves which was obtained by using the finite element method and the Hertz contact theory.This research results lay a foundation for dynamic relia-bility analysis and fatigue life prediction of the gear transmission system of a wind turbine.

  9. 覆冰输电线结构及载荷对舞动的影响%Influence of conductor structure and loads on galloping of a transmission line

    Institute of Scientific and Technical Information of China (English)

    周坤涛; 郝淑英; 刘君; 张琪昌

    2012-01-01

    为深入研究导线结构形式对输电线路系统动力学特性影响,以及导线结构形式及气动扭转载荷对覆冰输电线路舞动规律及幅值的影响,采用ANSYS参数化设计语言编写了计算导线舞动的非线性有限元分析程序,计算得出了系统气动载荷作用下的时间历程曲线.发现:在相同的气象条件下,分裂导线的振幅明显大于单根导线,且分裂数越高,导线越容易在短时间内形成稳态的舞动,应尽量采用单根导线或减少导线分裂数;扭转气动力载荷对面内外舞动的规律及幅值影响不大,对扭转角的幅值有较大影响,因此可忽略扭转气动载荷对断线和倒塔的作用.%For profoundly understanding influence of conductor structure forms and aerodynamic torsion loads on dynamic characteristics, galloping law and amplitude of an iced transmission line, a computer program based on nonlinear finite element analysis was developed using ANSYS parametric design language, time history curves were computed. Results indicated that the galloping amplitude of the bundle conductors is obviously greater than that of a single conductor, time needed to enter a steady state of galloping decreases noticeably as more conductors are added; consequently, in the same weather conditions, single conductor and less conductors in bundle should be adopted; aerodynamic torsion loads have slight influence on galloping law and amplitude for in-plane and out-of-plane galloping, but have a greater effect on amplitude of torsion angle; therefore the effect of aerodynamic torsion loads on breaking of an iced transmission line and its towers can be ignored.

  10. Research on Comprehensive Problems of Metro Transmission Network Full-ServiceLoad%移动本地传送网全业务承载的综合问题研究

    Institute of Scientific and Technical Information of China (English)

    张鹏; 李德; 晏琳; 刘炜

    2016-01-01

    With the rapid development of enterprise business and family business, the transmission networks now face bottlenecks like bandwidth ifxed and mobile coordination planning and network maintenance procedure dividing. The Hunan branch tried to ifnger out the method, clarify the problem, pin down the solution by pilot projects. Based on the present situation of enterprise and home broadband services of Shaoyang branch of CMCC, this article analyzed the problems, explored the solutions of different scenarios, and optimized the handling mechanism of network failures. The results veriifed that it can improve the quality of network and make customer satisifed. The planning and maintenance method of metro transmission network full-service load has been found.%伴随集客、家客等全业务的快速发展,移动本地传输网承载面临着传输带宽固移协同规划、网络维护流程分化等瓶颈。湖南移动公司通过试点来寻找解决问题的途径、理清问题、明确解决方案。基于中国移动通信集团湖南有限公司邵阳分公司集客、家客业务承载现状,通过理清集客、家客业务发展过程中存在的问题,探索不同场景的解决方案,优化网络故障处理机制,在提升网络质量的同时,提高了客户满意度。寻找到移动本地传送网全业务承载的规划和维护方法。

  11. Transmission eigenvalues

    Science.gov (United States)

    Cakoni, Fioralba; Haddar, Houssem

    2013-10-01

    In inverse scattering theory, transmission eigenvalues can be seen as the extension of the notion of resonant frequencies for impenetrable objects to the case of penetrable dielectrics. The transmission eigenvalue problem is a relatively late arrival to the spectral theory of partial differential equations. Its first appearance was in 1986 in a paper by Kirsch who was investigating the denseness of far-field patterns for scattering solutions of the Helmholtz equation or, in more modern terminology, the injectivity of the far-field operator [1]. The paper of Kirsch was soon followed by a more systematic study by Colton and Monk in the context of developing the dual space method for solving the inverse scattering problem for acoustic waves in an inhomogeneous medium [2]. In this paper they showed that for a spherically stratified media transmission eigenvalues existed and formed a discrete set. Numerical examples were also given showing that in principle transmission eigenvalues could be determined from the far-field data. This first period of interest in transmission eigenvalues was concluded with papers by Colton et al in 1989 [3] and Rynne and Sleeman in 1991 [4] showing that for an inhomogeneous medium (not necessarily spherically stratified) transmission eigenvalues, if they existed, formed a discrete set. For the next seventeen years transmission eigenvalues were ignored. This was mainly due to the fact that, with the introduction of various sampling methods to determine the shape of an inhomogeneous medium from far-field data, transmission eigenvalues were something to be avoided and hence the fact that transmission eigenvalues formed at most a discrete set was deemed to be sufficient. In addition, questions related to the existence of transmission eigenvalues or the structure of associated eigenvectors were recognized as being particularly difficult due to the nonlinearity of the eigenvalue problem and the special structure of the associated transmission

  12. Load Measurements

    DEFF Research Database (Denmark)

    Kock, Carsten Weber; Vesth, Allan

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regarding...... the fatigue loads, the rotor, blades and tower moments are presented. The fatigue loads are evaluated using rainflow counting described in detail in Ref. [1]. The 1Hz equivalent load ranges are calculated at different wind speeds. All information regarding the instrumentation is collected in [ref 4] and [ref...

  13. Investigation into the Influence of Transmission Parameter Variation on the First Gear Pair Loading Conditions%重要参数对齿轮副承载情况影响规律研究

    Institute of Scientific and Technical Information of China (English)

    冯慧华; 董彪; 尚蛟; 鲁守卫; 康黎云

    2011-01-01

    建立了某轿车变速器一挡传动齿轮副啮合状态有限元分析模型,基于显式动力学理论,对最大转矩工况下该传动副的瞬态啮合过程进行了动力学仿真计算,得到了轮齿齿面与齿根危险区域的主应力、等效应力的幅值与瞬态变化过程等结果.在此基础上,研究了发动机输出转矩、齿轮轴刚度、安装误差以及齿根过渡圆角等参数变化对该一挡传动齿轮副轮齿承载状况的影响权重与规律,为以改善强度及可靠性为目标的结构方案修改及工艺参数确定提供了重要参考.%Finite element (FE) model of transmission's first gear pair was built. Based on explicit dynamic theory, transient meshing process of the gear pair under maximum engine output torque was simulated. At the critical spots of the gear teeth's surfaces and roots, the amplitudes of main principle stresses and equivalent stresses, as well as their changing patterns were obtained. On the basis of the FE analysis model, the investigation was conducted to find out the influencing weights and changing rules of some important factors on the loading conditions of the gear pair,such as stiffness of gear shaft, assembling error, as well as tooth root fillet radius, etc. The results and conclusions from this research work can provide essential information for structural scheme modification to achieve higher strength and reliability, as well as to determine the processing and assembling parameters.

  14. Metamaterial Loadings for Waveguide Miniaturization

    CERN Document Server

    Odabasi, H

    2013-01-01

    We show that a rectangular metallic waveguide loaded with metamaterial elements consisting of electric-field coupled (ELC) resonators placed at the side walls can operate well below the cutoff frequency of the respective unloaded waveguide. The dispersion diagrams indicate that propagating modes in ELC-loaded waveguides are of forward-type for both TE and TM modes. We also study the dispersion diagram and transmission characteristics of rectangular metallic waveguides simultaneously loaded with ELCs and split ring resonators (SRRs). Such doubly-loaded waveguides can support both forward wave and backward waves, and provide independent control of the propagation characteristics for the respective modes.

  15. Load Measurements

    DEFF Research Database (Denmark)

    Vesth, Allan; Kock, Carsten Weber

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regardi...

  16. Load Measurements

    DEFF Research Database (Denmark)

    Kock, Carsten Weber; Vesth, Allan

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regarding...

  17. Regional transmission subsystem planning

    Energy Technology Data Exchange (ETDEWEB)

    Costa Bortoni, Edson da [Quadrante Softwares Especializados Ltda., Itajuba, MG (Brazil); Bajay, Sergio Valdir; Barros Correia, Paulo de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica; Santos, Afonso Henriques Moreira; Haddad, Jamil [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    This work presents an approach for the planning of transmission systems by employing mixed--integer linear programming to obtain a cost and operating characteristics optimized system. The voltage loop equations are written in a modified form, so that, at the end of the analysis, the model behaves as a DC power flow, with the help of the two Kirchhoff`s laws, exempting the need of interaction with an external power flow program for analysis of the line loading. The model considers the occurrence of contingencies, so that the final result is a network robust to the most severe contingencies. This whole technique is adapted to the regional electric power transmission subsystems. (author) 9 refs., 4 figs.

  18. HIV Transmission

    Science.gov (United States)

    ... Abroad Treatment Basic Statistics Get Tested Find an HIV testing site near you. Enter ZIP code or city Follow HIV/AIDS CDC HIV CDC HIV/AIDS See RSS | ... on HIV Syndicated Content Website Feedback HIV/AIDS HIV Transmission Language: English (US) Español (Spanish) Recommend ...

  19. Stress transmission in soil

    DEFF Research Database (Denmark)

    Lamandé, Mathieu; Schjønning, Per

    the soil-tyre interface were measured in separate tests by 17 stress transducers across the width of the tyres. The results showed that the inflation pressure controlled the level of maximum stresses at 0.3 m depth, while the wheel load was correlated to the measured stresses at 0.9 m depth. This supports......We urgently need increased quantitative knowledge on stress transmission in real soils loaded with agricultural machinery. 3D measurements of vertical stresses under tracked wheels were performed in situ in a Stagnic Luvisol (clay content 20 %) continuously cropped with small grain cereals....... The tests took place in the spring at field capacity when the topsoil had not been tilled for 1½ year. Two Nokian ELS Radial-ply tyres (800/50R34 and 560/45R22.5) were loaded with two specific loads (30 kN and 60 kN). We used rated tyre inflation pressures for traffic in the field (≤10 km h-1 driving speed...

  20. Dielectrically Loaded Biconical Antennas

    Science.gov (United States)

    Nusseibeh, Fouad Ahmed

    1995-01-01

    Biconical antennas are of great interest to those who deal with broadband applications including the transmission/reception of pulses. In particular, wide-angle conical antennas are an attractive choice in many applications including Electronic Support Measures (ESM) and the measurements of transient surface currents and charge densities on aircraft. Dielectric loading in the interior region of a conical antenna can be used to reduce the size of the antenna especially at low frequencies and/or for structural strength. Therefore, having an analytical solution for the input impedance and the frequency response is very helpful in optimizing the design and understanding the behavior of the antenna. From the quasi-analytical solution for the input impedance and the electric field of a wide-angle conical antenna, it can be seen that the dielectric loading in the antenna region improves the input impedance at low frequencies, but increases the number of resonance points and the magnitude of these peaks. When an inhomogeneous dielectric load is used, the magnitude of the resonance peaks is decreased (depending on the way the load is distributed), improving the input impedance of the antenna significantly. Introducing a dielectric load in the interior region of an electrically short receiving cone makes the antenna behave as an electrically longer antenna. However, this is not true for the case for electrical1y long antennas. For the case of pulse transmission, the dielectric load affects only the amplitude. Of course, if the dielectric fills the whole space, both transmitting and receiving antennas behave as electrically longer antennas.

  1. Tornado risk model for transmission line design

    CSIR Research Space (South Africa)

    Milford, RV

    1997-11-01

    Full Text Available is in combination with ice loading. The wind load used in most codes of practice and design recommendations for transmission line design have until recently been based almost exclusively on large-scale wind storms, which may include severe storms such as hurricanes...

  2. Economic feasible supply for small loads in rural areas, small villages and cities based in electric power transmission lines equipped with energized lighting rods; Suprimento economico de cargas rurais e de pequenas vilas e cidades atraves de linhas de transmissao equipadas com cabos para-raios energizados

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Manuel L.B. [Escola Federal de Engenharia de Itajuba, MG (Brazil). Inst. de Engenharia Eletrica; D`Ajuz, Ary; Pazo Blanco, Flavio A.F. [ELETRONORTE, Belem, PA (Brazil); Junior, Helio Pessoa de O.

    1997-12-31

    This paper describes the general aspects regarding the supply of small loads close to the main transmission lines. The proposed approach is to use the transmission lines over head ground wires that are energized by a zero sequence source. The main technical and economical aspects of the proposed system are presented and discussed. Details of the system constructed by ELETRONORTE and CERON at Rondonia are shown. Finally, a comparison of the economic aspects of the present proposal and the possible conventional solutions is presented. This system is in operation in Rondonia supplying the city of Jaru since December 1995. (author) 8 refs. 10 figs., 1 tab.; e-mail: martinez at gerson.iee.efei.rmg.br

  3. Load compensation for single phase system using series active filter

    African Journals Online (AJOL)

    user

    transmission system to low voltage distribution system, quite a good number of series ... Keywords: Active power filter (APF), current source type of harmonic load .... voltage source type harmonic loads are having diode rectifier with smoothing.

  4. A new class of negative refractive index transmission line

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We propose a new class of negative refractive index transmission line in which ideal operational amplifiers are applied to form the periodically loaded negative-impedance-converted inductors and capacitors. The phase response of the new transmission line is opposite to that of a positive refractive index conventional transmission line. Unlike the existing negative refractive index transmission line, the new negative refractive index transmission line is non-dispersive and thus can lead to many novel applications such as designing new broadband devices.

  5. Electrothermal Coordination in Cable Based Transmission Grids

    DEFF Research Database (Denmark)

    Olsen, Rasmus Schmidt; Holbøll, Joachim; Gudmundsdottir, Unnur Stella

    2013-01-01

    Electrothermal coordination (ETC) is introduced for cable based transmission grids. ETC is the term covering operation and planning of transmission systems based on temperature, instead of current. ETC consists of one part covering the load conditions of the system and one covering the thermal...... to be beneficial for both operator and system planner. It is shown how the thermal behavior can be monitored in real-time during normal dynamic load and during emergencies. In that way, ETC enables cables to be loaded above their normal rating, while maintaining high reliability of the system, which potentially...

  6. Iron load

    Directory of Open Access Journals (Sweden)

    Filippo Cassarà

    2013-03-01

    Full Text Available Recent research addressed the main role of hepcidin in the regulation of iron metabolism. However, while this mechanism could be relevant in causing iron load in Thalassemia Intermedia and Sickle-Cell Anemia, its role in Thalassemia Major (TM is marginal. This is mainly due to the high impact of transfusional requirement into the severe increase of body iron. Moreover, the damage of iron load may be worsened by infections, as HCV hepatitis, or liver and endocrinological damage. One of the most relevant associations was found between splenectomy and increase of risk for mortality due,probably, to more severe iron load. These issues suggest as morbidity and mortality of this group of patients they do not depend only by our ability in controlling heart damage but even in preventing or treating particular infections and complications. This finding is supported by the impairment of survival curves in patients with complications different from heart damage. However, because, during recent years different direct and indirect methods to detect iron overload in patients affected by secondary hemochromatosis have been implemented, our ability to maintain under control iron load is significantly improved. Anyway, the future in iron load management remains to be able to have an iron load map of our body for targeting chelation and other medical treatment according to the single organ damage.

  7. 变载荷下风力发电机行星齿轮传动系统齿轮-轴承耦合动力学特性%Gear-bearing coupling dynamics characteristics of wind turbine planetary gear transmission system under variable load

    Institute of Scientific and Technical Information of China (English)

    周志刚; 秦大同; 杨军; 陈会涛

    2012-01-01

    Considering that the transmission system of wind turbine works in complex and changing load environment caused by stochastic wind speed,this paper uses sparse least squares support vector machine(SL-SVM) to simulate wind speed of true wind field,and obtains time-varying wind load caused by stochastic wind speed.The lumped-parameter method is used to develop a dynamic model of planetary gear transmission system of wind turbine coupled with bearing.The model includes the varying wind load,time-vary mesh stiffness of gear pair and time-vary stiffness of rolling element bearing.The numerical method is used to simulate the dynamic performance of planetary gear system of Multibrid Technology Wind Turbine with 1.5 MW rated power.The vibration displacement responses of the transmission system are obtained as well as dynamic meshing force each pair of gear and nonlinear bearing forces.The research can provide a foundation for optimizing dynamic performance and reliable design of gear transmission system of wind generator.%根据风力发电机传动系统在随机风场中复杂变工况的工作特点,建立了最小二乘支持向量机风场随机风速模型,获得了由随机风速引起的时变风载荷。采用集中质量参数法建立了风力发电机行星齿轮传动系统中齿轮滚动轴承耦合动力学模型,考虑了风力发电机行星齿轮传动的变风载输入、齿轮时变啮合刚度和滚动轴承时变刚度等影响因素,对变风速下1.5MW半直驱风力发电机行星齿轮传动系统的动力学特性进行了仿真计算分析,求得了变风速下行星齿轮传动系统的振动位移、各齿轮副的动态啮合力和非线性动态轴承力,为风力发电机传动系统的动态性能优化和可靠性设计奠定了基础。

  8. IEC及GB规范在安哥拉220 kV输电线路导线风荷载计算中的对比分析%Application of IEC norm and GB code in wire wind load calculation for a 220kV power transmission line in Angola and comparison of difference

    Institute of Scientific and Technical Information of China (English)

    甘凯元

    2016-01-01

    Taking a 220 kV power transmission line in Republic of Angola as example, the Code for designing of 110~750kV overhead transmission line(GB50545-2010)of China was compared with the Design criteria of over⁃head transmission lines(IEC 60826-2003). Their difference in wire wind load calculation was analyzed. The re⁃sults of calculation demonstrate that their principles of defining basic wind velocity are identical;but different reoc⁃currence periods were adopted for different voltage levels in accordance with GB code. For the wire wind load calcu⁃lation of 2C-SZ41-24 type tower, the standard wind pressure and horizontal wire wind load of IEC norm are about 1.81and 1.3 times as much as that of GB code respectively.%以安哥拉220 kV输电线路为例,将国内《110~750 kV架空输电线路设计规范》(GB 50545-2010)与国际电工委员会《Design criteria of overhead transmission lines》(IEC 60826-2003)做对比,分析两者在导线风荷载计算中的差异性。通过计算得知:IEC与GB在基本风速的确定原则一致,但是GB根据不同的电压等级采用不同的重现期;对导线风荷载,IEC计算风压标准值约为国标的1.81倍,IEC计算导线水平风荷载约为国标的1.30倍(以2C-SZ41-24型杆塔为例)。

  9. Modeling of STATCOM under different loading conditions

    DEFF Research Database (Denmark)

    George, G.J.; Ramachandran, Rakesh; Kowsalya, M.

    2012-01-01

    This paper deals with the study and analysis of Flexible AC Transmission Systems (FACTS), mainly the modeling of STATCOM. Reactive Power Compensation plays a very important role in the transmission of Electric Power. A comparative study of how the reactive power is injected into the transmission ...... system with and without STATCOM under different loading condition is also illustrated in this paper. Simulations are performed using MATLAB/SIMULINK software. © 2012 IEEE....

  10. Beam loading

    CERN Document Server

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  11. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  12. Load sensor

    NARCIS (Netherlands)

    Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

    2007-01-01

    The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder for

  13. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  14. Essentials of filoviral load quantification.

    Science.gov (United States)

    Cnops, Lieselotte; van Griensven, Johan; Honko, Anna N; Bausch, Daniel G; Sprecher, Armand; Hill, Charles E; Colebunders, Robert; Johnson, Joshua C; Griffiths, Anthony; Palacios, Gustavo F; Kraft, Colleen S; Kobinger, Gary; Hewlett, Angela; Norwood, David A; Sabeti, Pardis; Jahrling, Peter B; Formenty, Pierre; Kuhn, Jens H; Ariën, Kevin K

    2016-07-01

    Quantitative measurement of viral load is an important parameter in the management of filovirus disease outbreaks because viral load correlates with severity of disease, survival, and infectivity. During the ongoing Ebola virus disease outbreak in parts of Western Africa, most assays used in the detection of Ebola virus disease by more than 44 diagnostic laboratories yielded qualitative results. Regulatory hurdles involved in validating quantitative assays and the urgent need for a rapid Ebola virus disease diagnosis precluded development of validated quantitative assays during the outbreak. Because of sparse quantitative data obtained from these outbreaks, opportunities for study of correlations between patient outcome, changes in viral load during the course of an outbreak, disease course in asymptomatic individuals, and the potential for virus transmission between infected patients and contacts have been limited. We strongly urge the continued development of quantitative viral load assays to carefully evaluate these parameters in future outbreaks of filovirus disease.

  15. Design of a Gear Transmission Loading Fatigue Test Bench Have Ability of Hydraulic Power Recovery%一种液压功率回收型齿轮传动加载疲劳试验台的设计

    Institute of Scientific and Technical Information of China (English)

    王延忠; 刘文; 潘广悦; 刘元鹏

    2016-01-01

    基于液压补偿功率回收理论,采用容积调压加载的方式,结合PLC在液压系统的控制应用,针对试验台的液压系统及测控系统进行设计,并对液压系统的主要液压元件试验参数匹配关系进行理论计算.由理论关系式得出液压马达排量的调节对试验台的驱动转速与加载转矩的影响,并依照系统原理搭建试验台,通过试验检测,得到功率回收效率.%Based on the hydraulic power recovery compensation theory,by ways of regulating the volume of loaded and PLC control applications in the hydraulic system,the hydraulic system,the measurement and control system of the test bench are designed primarily.The composition principle of the hydraulic system and the matching relationship of main hy-draulic components test parameters are calculated.The influence of hydraulic motor displacement on the driving speed and the load torque can be obtained by the theoretical formula,and a test bench is set up to detect the power recovery efficiency.

  16. Impact of Investments in Generating Units and Transmission and Distribution Power Grids by 2025 on Voltage Stability and Branches Load in ENERGA SA Operational Territory – Main Findings of Research Project

    Directory of Open Access Journals (Sweden)

    Dominik Falkowski

    2013-03-01

    Full Text Available The article summarizes a research project which was conducted in order to ensure what will be the influence of future investments and changes in the Polish Power System on the stability and functionality of the ENERGA SA distribution grid system. Development of the ENERGA SA distribution grid system was also included. Only stable states were tested for various cases of system load and generation in power plants (the Nuclear Power Plant in Żarnowiec was taken into account and also in wind farms. The system was also tested in N-1 and N-2 states. The result of this study is an overall evaluation of the ENERGA SA distribution grid condition, as well as the identification of potential weak points inside this structure.

  17. Contact analysis and load distribution of double-envelop hourglassworm gearing affected by errors and load

    Institute of Scientific and Technical Information of China (English)

    XU Wujiao; QIN Datong; SHI Wankai

    2003-01-01

    An approach for the contact analysis and load distribution of double-envelop hourglass worm gearing is presented,which is based on a 3-D elastic contact finite element method (FEM) model that 3ccommodates the influence of errors and load.As compared with existing tooth contact analysis model that assumes rigidity for the contacting surfaces, the proposed model provides a more realistic analysis on the contact patterns, the distribution of contact load and transmission errors. It is also capable of exploring the influence of different errors on meshing performances, the contact deformation, the shift of the contact zone and load share among the meshing tooth-pairs under different load.

  18. Survey of Transmission Cost Allocation Methodologies for Regional Transmission Organizations

    Energy Technology Data Exchange (ETDEWEB)

    Fink, S.; Porter, K.; Mudd, C.; Rogers, J.

    2011-02-01

    The report presents transmission cost allocation methodologies for reliability transmission projects, generation interconnection, and economic transmission projects for all Regional Transmission Organizations.

  19. Modelación de las cargas de reacción en los apoyos de los árboles de la Transmisión por tornillo sinfín. // Reaction loads models in shafts supports of worm gear transmissions.

    Directory of Open Access Journals (Sweden)

    G. Rivero Llerena

    2006-05-01

    Full Text Available El análisis y cálculo de las cargas que se generan en los apoyos de los árboles de los conjuntos mecánicos rotatorios, resultaun proceso complejo pero imprescindible en la tarea de selección de los rodamientos, por ello en el presente trabajo sepropone el uso de las NTIC como herramientas efectivas de diseño y modelación para la solución de este problema. En estainvestigación se trata el caso de la transmisión por tornillo sinfín por su importancia en los accionamientos industriales y enotros campos, se ha formalizado en tres modelos, el análisis de las cargas de operación y de reacción que se producendurante el funcionamiento. Se presentan los resultados que puede brindar el software de cálculo creado, usando el paquetede información que contiene la modelación realizada para obtener una respuesta ágil y exacta de las cargas de reacciónresultantes en los apoyos de árboles.Palabras claves: Sinfín, rodamiento, modelación.______________________________________________________________________________Abstract.The analysis and calculation of the loads generated in the shafts supports of the rotational machines, is a complex butindispensable process in the task of selection rolling bearings. The present paper exposes the use of the NTIC like effectivetools of design and modelling in order to solve this problem. The worm gear transmission case is studied in thisinvestigation because their importance in the industrial machinery and other fields, the analysis of the operation andreaction loads has been formalized in three models. Also it is presented the results of software for calculation, using theinformation package that contains the three models for obtaining an agile and exact answer of the resulting reaction loads inthe shafts supports.Key words: Worm gear, bearing, modelling.

  20. Transmission properties of cryogenic twisted pair filters

    Energy Technology Data Exchange (ETDEWEB)

    Song, Woon; Rehman, Mushtaq; Chong, Yonuk [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Ryu, Sangwan [Chonnam National University, Gwangju (Korea, Republic of)

    2010-12-15

    We fabricated a cryogenic low pass filter that consists of twisted pairs of manganin wires wrapped in copper tape and measured its transmission characteristics at frequencies up to 18 GHz. The dependence of the microwave transmission characteristics on the filter length was studied, which showed that a filter of length 1.0 m had a 70-dB attenuation at 1 GHz. We also studied the dependence of common- and differential-mode transmission on the number of twists per unit length and found that the number of twists per unit length affects differential-mode transmission but not common-mode transmission. Because the shielded twisted pair filter is more compact than a conventional copper powder filter, it can solve the space and thermal load issues when many cables are required for precision electronic transport experiments at low temperatures.

  1. Advanced Rotorcraft Transmission (ART) Program summary

    Science.gov (United States)

    Krantz, T. L.; Kish, J. G.

    1992-07-01

    The Advanced Rotorcraft Transmission (ART) Program was initiated to advance the state of the art for rotorcraft transmissions. The goal of the ART Program was to develop and demonstrate the technologies needed to reduce transmission weight by 25 pct and reduce noise by 10 dB while obtaining a 5000 hr 'mean time between failure'. The research done under the ART Program is summarized. A split path design was selected as best able to meet the program goals. Key part technologies needed for this design were identified, studied, and developed. Two of these technologies are discussed in detail: the load sharing of split path designs including the use of a compliant elastomeric torque splitter and the application of a high ratio, low pitch line velocity gear mesh. Development of an angular contact spherical roller bearing, transmission error analysis, and fretting fatigue testing are discussed. The technologies for a light weight, quiet, and reliable rotorcraft transmission were demonstrated.

  2. Advanced Rotorcraft Transmission (ART) program status

    Science.gov (United States)

    Bossler, Robert; Heath, Gregory

    1991-01-01

    Reported herein is work done on the Advanced Rotorcraft Transmission by McDonnell Douglas Helicopter Company under Army/NASA contract. The novel concept pursued includes the use of face gears for power transmission and a torque splitting arrangement. The design reduces the size and weight of the corner-turning hardware and the next reduction stage. New methods of analyzing face gears have increased confidence in their usefulness. Test gears have been designed and manufactured for power transmission testing on the NASA-Lewis spiral bevel test rig. Transmission design effort has included finite element modeling of the split torque paths to assure equal deflection under load. A finite element model of the Apache main transmission has been completed to substantiate noise prediction methods. A positive engagement overrunning clutch design is described. Test spur gears have been made by near-net-shape forging from five different materials. Three housing materials have been procured for evaluation testing.

  3. Radio Frequency Power Load and Associated Method

    Science.gov (United States)

    Srinivasan, V. Karthik (Inventor); Freestone, Todd M. (Inventor); Sims, William Herbert, III (Inventor)

    2014-01-01

    A radio frequency power load and associated method. A radio frequency power load apparatus may include a container with an ionized fluid therein. The apparatus may include one conductor immersed in a fluid and another conductor electrically connected to the container. A radio frequency transmission system may include a radio frequency transmitter, a radio frequency amplifier connected to the transmitter and a radio frequency power load apparatus connected to the amplifier. The apparatus may include a fluid having an ion source therein, one conductor immersed in a fluid, and another conductor electrically connected to the container. A method of dissipating power generated by a radio frequency transmission system may include constructing a waveguide with ionized fluid in a container and connecting the waveguide to an amplifier of the transmission system.

  4. EM transmission-line metamaterials

    Directory of Open Access Journals (Sweden)

    George V. Eleftheriades

    2009-03-01

    Full Text Available Metamaterials are understood to be artificially engineered materials that exhibit unusual or difficult to obtain electromagnetic (EM properties. Such properties would include negative or low values of permittivity, permeability and index of refraction. In this article, we review the fundamentals of metamaterials with emphasis on negative-refractive-index ones, which are synthesized using loaded transmission lines. A number of applications of such metamaterials are discussed, including peculiar lenses that can overcome the diffraction limit and small antennas for emerging wireless communication applications.

  5. Transmission diamond imaging detector

    Energy Technology Data Exchange (ETDEWEB)

    Smedley, John, E-mail: smedley@bnl.gov; Pinelli, Don; Gaoweia, Mengjia [Brookhaven National Laboratory, Upton, NY (United States); Muller, Erik; Ding, Wenxiang; Zhou, Tianyi [Stony Brook University, Stony Brook, NY (United States); Bohon, Jen [Case Center for Synchrotron Biosciences, Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH (United States)

    2016-07-27

    Many modern synchrotron techniques are trending toward use of high flux beams and/or beams which require enhanced stability and precise understanding of beam position and intensity from the front end of the beamline all the way to the sample. For high flux beams, major challenges include heat load management in optics (including the vacuum windows) and a mechanism of real-time volumetric measurement of beam properties such as flux, position, and morphology. For beam stability in these environments, feedback from such measurements directly to control systems for optical elements or to sample positioning stages would be invaluable. To address these challenges, we are developing diamond-based instrumented vacuum windows with integrated volumetric x-ray intensity, beam profile and beam-position monitoring capabilities. A 50 µm thick single crystal diamond has been lithographically patterned to produce 60 µm pixels, creating a >1kilopixel free-standing transmission imaging detector. This device, coupled with a custom, FPGA-based readout, has been used to image both white and monochromatic x-ray beams and capture the last x-ray photons at the National Synchrotron Light Source (NSLS). This technology will form the basis for the instrumented end-station window of the x-ray footprinting beamline (XFP) at NSLS-II.

  6. Load testing circuit

    DEFF Research Database (Denmark)

    2009-01-01

    A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load...

  7. Parameters optimization for magnetic resonance coupling wireless power transmission.

    Science.gov (United States)

    Li, Changsheng; Zhang, He; Jiang, Xiaohua

    2014-01-01

    Taking maximum power transmission and power stable transmission as research objectives, optimal design for the wireless power transmission system based on magnetic resonance coupling is carried out in this paper. Firstly, based on the mutual coupling model, mathematical expressions of optimal coupling coefficients for the maximum power transmission target are deduced. Whereafter, methods of enhancing power transmission stability based on parameters optimal design are investigated. It is found that the sensitivity of the load power to the transmission parameters can be reduced and the power transmission stability can be enhanced by improving the system resonance frequency or coupling coefficient between the driving/pick-up coil and the transmission/receiving coil. Experiment results are well conformed to the theoretical analysis conclusions.

  8. Parameters Optimization for Magnetic Resonance Coupling Wireless Power Transmission

    Directory of Open Access Journals (Sweden)

    Changsheng Li

    2014-01-01

    Full Text Available Taking maximum power transmission and power stable transmission as research objectives, optimal design for the wireless power transmission system based on magnetic resonance coupling is carried out in this paper. Firstly, based on the mutual coupling model, mathematical expressions of optimal coupling coefficients for the maximum power transmission target are deduced. Whereafter, methods of enhancing power transmission stability based on parameters optimal design are investigated. It is found that the sensitivity of the load power to the transmission parameters can be reduced and the power transmission stability can be enhanced by improving the system resonance frequency or coupling coefficient between the driving/pick-up coil and the transmission/receiving coil. Experiment results are well conformed to the theoretical analysis conclusions.

  9. Integrated Transmission and Distribution Control

    Energy Technology Data Exchange (ETDEWEB)

    Kalsi, Karanjit; Fuller, Jason C.; Tuffner, Francis K.; Lian, Jianming; Zhang, Wei; Marinovici, Laurentiu D.; Fisher, Andrew R.; Chassin, Forrest S.; Hauer, Matthew L.

    2013-01-16

    allows the load flow interactions between the bulk power system and end-use loads to be explicitly modeled. Power system interactions are modeled down to time intervals as short as 1-second. Another practical issue is that the size and complexity of typical distribution systems makes direct integration with transmission models computationally intractable. Hence, the focus of the next main task is to develop reduced-order controllable models for some of the smart grid assets. In particular, HVAC units, which are a type of Thermostatically Controlled Loads (TCLs), are considered. The reduced-order modeling approach can be extended to other smart grid assets, like water heaters, PVs and PHEVs. Closed-loop control strategies are designed for a population of HVAC units under realistic conditions. The proposed load controller is fully responsive and achieves the control objective without sacrificing the end-use performance. Finally, using the T&D simulation platform, the benefits to the bulk power system are demonstrated by controlling smart grid assets under different demand response closed-loop control strategies.

  10. Open Access Transmission Tariff: Effective December 18, 1998 (Revised June 16, 1999).

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1999-06-16

    Bonneville will provide Network Integration Transmission Service pursuant to the terms and conditions contained in this Tariff and Service Agreement. The service that Bonneville will provide under this Tariff allows a Transmission Customer to integrate, economically dispatch and regulate its current and planned Network Resources to serve its Network Load. Network Integration Transmission Service also may be used by the Transmission Customer to deliver nonfirm energy purchases to its Network Load without additional charge. To the extent that the transmission path for moving power from a Network Resource to a Network Load includes the Eastern and Southern Interties, the terms and conditions for service over such intertie facilities are provided under Part 2 of this Tariff. Also, transmission service for third-party sales which are not designated as Network Load will be provided under Bonneville's Point-to-Point Transmission Service (Part 2 of this Tariff).

  11. Stabilizing control for power converters connected to transmission lines

    NARCIS (Netherlands)

    Zainea, Marius; Schaft, Arjan van der; Buisson, Jean

    2007-01-01

    This paper proposes a switching control strategy for the set-point stabilization of a power converter connected via a transmission line to a resistive load. The strategy employs a Lyapunov function that is directly based on energy considerations of the power converter, as well as of the transmission

  12. 间隙非线性圆柱齿轮分流传动系统动力学与均载特性分析%Dynamic and load sharing characteristic analysis of a nonlinear cylindrical gear split-torque transmission system with backlash

    Institute of Scientific and Technical Information of China (English)

    桂永方; 朱如鹏; 靳广虎; 李枝军

    2014-01-01

    Based on the method of lumped parameters,a dynamic model was established for a 2-input cylindrical gear split-torque transmission system considering time-varying mesh stiffness,backlashes and mesh damping.Through solving its dynamic equations with the fourth order Runge-Kutta method,the dynamic load sharing coefficients of the system were acquired.The results showed that the load sharing coefficient of the split-torque stages increases with increase in backlash of single branch in split-torque stages,and it decreases with increase in backlash of dual-branch in split-torque stages;the backlashes of single-branch and dual-branch in split-torque stages have a smaller impact on the load sharing coefficient of synthesized torque stages;the load sharing coefficient of the synthesized torque stages increases with increase in backlash of single branch in synthesized torque stages,and it decreases with increase in backlash of dual-branch in synthesized torque stages;the backlashes of single-branch and dual-branch in synthesized torque stages have a smaller impact on the load sharing coefficient of split-torque stages;the dynamic load coefficient increases with increase in backlash of dual-branch.%基于集中参数,建立了双输入圆柱齿轮分流传动系统的弯扭耦合动力学模型,模型中考虑了各齿轮副间的齿侧间隙、时变啮合刚度、啮合阻尼等因素。采用四阶龙格-库塔法,求解系统动力学方程,获得了系统的动力学均载系数。分析了齿侧间隙对均载系数的影响,获得了齿侧间隙对分流级、并车级均载系数的变化规律。研究结果表明:分流级均载系数随分流级单分支齿侧间隙增加而增大,随分流级双分支齿侧间隙增加而减小;分流级单分支、双分支齿侧间隙对并车级均载系数影响较小;并车级均载随并车级单分支齿侧间隙增加而增大,随并车级双分支齿侧间隙增加而减小;并车级单分支、双

  13. Pregnant and breastfeeding women: A priority population for HIV viral load monitoring.

    Science.gov (United States)

    Myer, Landon; Essajee, Shaffiq; Broyles, Laura N; Watts, D Heather; Lesosky, Maia; El-Sadr, Wafaa M; Abrams, Elaine J

    2017-08-01

    Landon Myer and colleagues discuss viral load monitoring for pregnant HIV-positive women and those breastfeeding; ART treatments can suppress viral load and are key to preventing transmission to the child.

  14. Loads and loads and loads: The influence of prospective load, retrospective load, and ongoing task load in prospective memory

    Directory of Open Access Journals (Sweden)

    Beat eMeier

    2015-06-01

    Full Text Available In prospective memory tasks different kinds of load can occur. Adding a prospective memory task can impose a load on ongoing task performance. Adding ongoing task load can affect prospective memory performance. The existence of multiple target events increases prospective load and adding complexity to the to-be-remembered action increases retrospective load. In two experiments, we systematically examined the effects of these different types of load on prospective memory performance. Results showed an effect of prospective load on costs in the ongoing task for categorical targets (Experiment 2, but not for specific targets (Experiment 1. Retrospective load and ongoing task load both affected remembering the retrospective component of the prospective memory task. We suggest that prospective load can enhance costs in the ongoing task due to additional monitoring requirements. Retrospective load and ongoing task load seem to impact the division of resources between the ongoing task and retrieval of the retrospective component, which may affect disengagement from the ongoing task. In general, the results demonstrate that the different types of load affect prospective memory differentially.

  15. Frequency Dependent Losses in Transmission Cable Conductors

    DEFF Research Database (Denmark)

    Olsen, Rasmus Schmidt; Holbøll, Joachim; Guðmundsdóttir, Unnur Stella

    2011-01-01

    Denmark is taking on the exciting project of undergrounding the electricity transmission grid. In 2009 it was decided by the Danish government to underground large parts of the 400 kV and the entire 132-150 kV transmission network before the end of 2030. For ensuring network stability...... and economical gain, such severe network changes necessitate correct estimation and optimisation of load conditions in the cable grid. Both IEC and IEEE have published standards for rating transmission cables' current carrying capacity. These standards are based on assumptions of a number of parameters...... of better calculation of the AC resistance of transmission cable conductors, in particular regarding higher frequencies. In this way, also losses under harmonics can be covered. Furthermore, the model is suitable for modelling of transient attenuation in high voltage cables. The AC resistance is calculated...

  16. Energy losses of superconducting power transmission cables in the grid

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Okholm, Jan; Lomholt, Karin

    2001-01-01

    One of the obvious motives for development of superconducting power transmission cables is reduction of transmission losses. Loss components in superconducting cables as well as in conventional cables have been examined. These losses are used for calculating the total energy losses of conventional...... as well as superconducting cables when they are placed in the electric power transmission network. It is concluded that high load connections are necessary to obtain energy saving by the use of HTSC cables. For selected high load connections, an energy saving of 40% is expected. It is shown...... that the thermal insulation and cooling machine efficiency are the most important loss element in a superconducting cable system...

  17. Cultural Transmission of Civicness

    DEFF Research Database (Denmark)

    Ljunge, Jan Martin

    2012-01-01

    This paper estimates the intergeneration transmission of civicness by studying second generation immigrants in 29 European countries with ancestry in 83 nations. There is significant transmission of civicness both on the mother’s and the father’s side. The estimates are quantitatively significant...... and provide evidence on the transmission of trustworthiness....

  18. Cultural Transmission of Civicness

    DEFF Research Database (Denmark)

    Ljunge, Jan Martin

    This paper estimates the intergeneration transmission of civicness by studying second generation immigrants in 29 European countries with ancestry in 83 nations. There is significant transmission of civicness both on the mother’s and the father’s side. The estimates are quantitatively significant...... and provide evidence on the transmission of trustworthiness....

  19. Coiled transmission line pulse generators

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Kenneth Fox (Columbia, MO)

    2010-11-09

    Methods and apparatus are provided for fabricating and constructing solid dielectric "Coiled Transmission Line" pulse generators in radial or axial coiled geometries. The pour and cure fabrication process enables a wide variety of geometries and form factors. The volume between the conductors is filled with liquid blends of monomers, polymers, oligomers, and/or cross-linkers and dielectric powders; and then cured to form high field strength and high dielectric constant solid dielectric transmission lines that intrinsically produce ideal rectangular high voltage pulses when charged and switched into matched impedance loads. Voltage levels may be increased by Marx and/or Blumlein principles incorporating spark gap or, preferentially, solid state switches (such as optically triggered thyristors) which produce reliable, high repetition rate operation. Moreover, these Marxed pulse generators can be DC charged and do not require additional pulse forming circuitry, pulse forming lines, transformers, or an a high voltage spark gap output switch. The apparatus accommodates a wide range of voltages, impedances, pulse durations, pulse repetition rates, and duty cycles. The resulting mobile or flight platform friendly cylindrical geometric configuration is much more compact, light-weight, and robust than conventional linear geometries, or pulse generators constructed from conventional components. Installing additional circuitry may accommodate optional pulse shape improvements. The Coiled Transmission Lines can also be connected in parallel to decrease the impedance, or in series to increase the pulse length.

  20. Profile modification to minimize spur gear dynamic loading

    Science.gov (United States)

    Lin, H. H.; Townsend, D. P.; Oswald, F. B.

    1989-01-01

    An analytical computer simulation program for dynamic modeling of low-contact-ratio spur gear systems is presented. The procedure computes the static transmission error of the gears operating under load and uses a fast Fourier transform to generate the frequency spectrum of the static transmission error at various tooth profile modifications. The dynamic loading response of an unmodified (perfect involute) gear pair was compared with that of gears with various profile modifications. Correlations were found between various profile modifications and the resulting dynamic loads. An effective error, obtained from frequency domain analysis of the static transmission error of the gears, gave a very good indication of the optimum profile modification to reduce gear dynamic loading. Design curves generated by dynamic simulation at various profile modifications are given for gear systems operated at various loads. Optimum profile modifications can be determined from these design curves for improved gear design.

  1. Modeling a data transmission network by means of the Teledacya information subsystems

    Science.gov (United States)

    Palmowska, K.

    1982-11-01

    Rapid assessment of the reasonableness of results from various kinds of prognostication fundamentals and assumptions concerning the development of data transmission networks, important with respect to the extent of loading on a long distance telecommunications transmission network was examined. Initial evaluations demonstrated that loading determined according to existing prediction methods has essential importance for the planning of an entire telecommunication network.

  2. Electrical load detection aparatus

    DEFF Research Database (Denmark)

    2010-01-01

    A load detection technique for a load comprising multiple frequency-dependant sub-loads comprises measuring a representation of the impedance characteristic of the load; providing stored representations of a multiplicity of impedance characteristics of the load; each one of the stored representat...

  3. The automotive transmission book

    CERN Document Server

    Fischer, Robert; Jürgens, Gunter; Najork, Rolf; Pollak, Burkhard

    2015-01-01

    This book presents essential information on systems and interactions in automotive transmission technology and outlines the methodologies used to analyze and develop transmission concepts and designs. Functions of and interactions between components and subassemblies of transmissions are introduced, providing a basis for designing transmission systems and for determining their potentials and properties in vehicle-specific applications: passenger cars, trucks, buses, tractors, and motorcycles. With these fundamentals the presentation provides universal resources for both state-of-the-art and future transmission technologies, including systems for electric and hybrid electric vehicles.

  4. 77 FR 64890 - Transmission Planning and Cost Allocation by Transmission Owning and Operating Public Utilities

    Science.gov (United States)

    2012-10-24

    ... are optimal given those expected changes in resources and load.\\60\\ AEP argues that Public Policy..., including consideration of changes driven by public policies (such as renewable portfolio standards, new... analyses to determine what transmission investments are optimal given these anticipated changes.\\65\\ It...

  5. Bordetella pertussis transmission.

    Science.gov (United States)

    Trainor, Elizabeth A; Nicholson, Tracy L; Merkel, Tod J

    2015-11-01

    Bordetella pertussis and B. bronchiseptica are Gram-negative bacterial respiratory pathogens. Bordetella pertussis is the causative agent of whooping cough and is considered a human-adapted variant of B. bronchiseptica. Bordetella pertussis and B. bronchiseptica share mechanisms of pathogenesis and are genetically closely related. However, despite the close genetic relatedness, these Bordetella species differ in several classic fundamental aspects of bacterial pathogens such as host range, pathologies and persistence. The development of the baboon model for the study of B. pertussis transmission, along with the development of the swine and mouse model for the study of B. bronchiseptica, has enabled the investigation of different aspects of transmission including the route, attack rate, role of bacterial and host factors, and the impact of vaccination on transmission. This review will focus on B. pertussis transmission and how animal models of B. pertussis transmission and transmission models using the closely related B. bronchiseptica have increased our understanding of B. pertussis transmission.

  6. Effect of delivery modes on blocking mother-to-child transmission of HBV in HBV-infected mothers with high viral load%分娩方式对高病毒载量的HBV感染母亲母婴阻断的影响

    Institute of Scientific and Technical Information of China (English)

    周明芳; 刘敏; 易为; 蔡晧东

    2016-01-01

    目的 探讨HBV高病毒载量孕妇的分娩方式对母婴阻断结果的影响.方法 选择2012年1月1日—2014年12月31日在我院分娩且HBV DNA≥1×106 copies/ml的孕妇570例,分析其分娩方式,检测所生婴儿出生时和完成全程乙型肝炎疫苗免疫后(7~12月龄)的HBV血清学标志物.结果 570例中,289例(50.7%)剖宫产分娩292例活婴(双胎3例),其中新生儿免疫成功270例(92.5%),免疫无应答3例(1.0%),HBV感染19例(6.5%);281例(49.3%)阴道分娩281例活婴,其中新生儿免疫成功252例(89.7%),免疫无应答4例(1.4%),HBV感染25例(8.9%).阴道分娩组所生婴儿母婴阻断失败率稍高于剖宫产组,但差异无统计学意义(8.9%vs 6.5%,χ2=1.153,P=0.283).结论 分娩方式对HBV从母亲血液渗透到婴儿体内无明显影响,对HBV母婴阻断效果无明显影响.%Objective To investigate the effect of delivery modes on blocking mother-to-child transmission of HBV in HBV-infected mothers with high viral load.Methods A total of 570 pregnant women with HBV DNA levels≥1×106 copies/ml, who delivered their babies at our hospital from January 1, 2012 to December 31, 2014, were selected. Their delivery modes were analyzed, and HBV serological markers at neonatal birth and after the whole hepatitis B vaccination (7-12 months old) were detected.Results Totally 292 infants (3 pairs of twins) were born to 289 mothers (50.7%) by caesarean section delivery, of whom 270 newborn infants (92.5%) had immune response to hepatitis B vaccine, 3 (1.0%) didn't have immune response, and 19 (6.5%) were infected with HBV. Totally 281 infants were born to 281 mothers (49.3%) by vaginal delivery, of whom 252 newborn infants (89.7%) had immune response to hepatitis B vaccine, 4 (1.4%) didn't have immune response, and 25 (8.9%) were infected with HBV. The failure rate in blocking mother-to-child transmission in the group of vaginal delivery was higher than that in the group of cesarean section delivery, but the

  7. On Dynamic Loads in Parallel Shaft Transmissions. 2. Parameter Study.

    Science.gov (United States)

    1987-12-01

    FORM 1626 ocT 96 For sale by the National Technical Inforration Serice. Sprirnrle i vdrl ni 1 i 1 t % .p- ...- M49. w w w ww w w w w w w w 0 Wi Z.~p r ~ r . a aif ~ ’ P ~ \\ , ’S %’*Ile

  8. Distribution load estimation (DLE)

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A.; Lehtonen, M. [VTT Energy, Espoo (Finland)

    1998-08-01

    The load research has produced customer class load models to convert the customers` annual energy consumption to hourly load values. The reliability of load models applied from a nation-wide sample is limited in any specific network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to find improvements to the load models or, in general, improvements to the load estimates. In Distribution Load Estimation (DLE) the measurements from the network are utilized to improve the customer class load models. The results of DLE will be new load models that better correspond to the loading of the distribution network but are still close to the original load models obtained by load research. The principal data flow of DLE is presented

  9. Application of face-gear drives in helicopter transmissions

    Science.gov (United States)

    Litvin, F. L.; Wang, J.-C.; Bossler, R. B., Jr.; Chen, Y.-J. D.; Heath, G.; Lewicki, D. G.

    1992-05-01

    The use of face gears in helicopter transmissions was explored. A light-weight, split torque transmission design utilizing face gears was described. Face-gear design and geometry were investigated. Topics included tooth generation, limiting inner and outer radii, tooth contact analysis, contact ratio, gear eccentricity, and structural stiffness. Design charts were developed to determine minimum and maximum face-gear inner and outer radii. Analytical study of transmission error showed face-gear drives were relatively insensitive to gear misalignment, but tooth contact was affected by misalignment. A method of localizing bearing contact to compensate for misalignment was explored. The proper choice of shaft support stiffness enabled good load sharing in the split torque transmission design. Face-gear experimental studies were also included and the feasibility of face gears in high-speed, high-load applications such as helicopter transmissions was demonstrated.

  10. Application of Face-Gear Drives in Helicopter Transmissions

    Science.gov (United States)

    Litvin, F. L.; Wang, J.-C.; Bossler, R. B., Jr.; Chen, Y.-J. D.; Heath, G.; Lewicki, D. G.

    1992-01-01

    The use of face gears in helicopter transmissions was explored. A light-weight, split torque transmission design utilizing face gears was described. Face-gear design and geometry were investigated. Topics included tooth generation, limiting inner and outer radii, tooth contact analysis, contact ratio, gear eccentricity, and structural stiffness. Design charts were developed to determine minimum and maximum face-gear inner and outer radii. Analytical study of transmission error showed face-gear drives were relatively insensitive to gear misalignment, but tooth contact was affected by misalignment. A method of localizing bearing contact to compensate for misalignment was explored. The proper choice of shaft support stiffness enabled good load sharing in the split torque transmission design. Face-gear experimental studies were also included and the feasibility of face gears in high-speed, high-load applications such as helicopter transmissions was demonstrated.

  11. Wind Loads on Structures

    DEFF Research Database (Denmark)

    Dyrbye, Claes; Hansen, Svend Ole

    pressure to structural response) and design criteria. Starting with an introduction of the wind load chain, the book moves on to meteorological considerations, atmospheric boundary layer, static wind load, dynamic wind load and scaling laws used in wind-tunnel tests. The dynamic wind load covers vibrations......Wind loads have to be taken into account when designing civil engineering structures. The wind load on structures can be systematised by means of the wind load chain: wind climate (global), terrain (wind at low height), aerodynamic response (wind load to pressure), mechanical response (wind...

  12. Distribution load estimation - DLE

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland)

    1996-12-31

    The load research project has produced statistical information in the form of load models to convert the figures of annual energy consumption to hourly load values. The reliability of load models is limited to a certain network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to make improvements in the load models. Distribution load estimation (DLE) is the method developed here to improve load estimates from the load models. The method is also quite cheap to apply as it utilises information that is already available in SCADA systems

  13. Wind Loads on Structures

    DEFF Research Database (Denmark)

    Dyrbye, Claes; Hansen, Svend Ole

    pressure to structural response) and design criteria. Starting with an introduction of the wind load chain, the book moves on to meteorological considerations, atmospheric boundary layer, static wind load, dynamic wind load and scaling laws used in wind-tunnel tests. The dynamic wind load covers vibrations......Wind loads have to be taken into account when designing civil engineering structures. The wind load on structures can be systematised by means of the wind load chain: wind climate (global), terrain (wind at low height), aerodynamic response (wind load to pressure), mechanical response (wind...

  14. Marginal pricing and supplement cost allocation in transmission open access

    Energy Technology Data Exchange (ETDEWEB)

    Rudnick, H.; Palma, R.; Fernandez, J.E. [Pontificia Univ. Catolica de Chile, Santiago (Chile). Escuela de Ingenieria

    1995-05-01

    The application of marginal costing to transmission pricing in open access schemes requires the collection of a supplement to finance the transmission systems. The paper describes the application of marginal cost based pricing in the Chilean power system and the difficulties faced in allocating the supplement among parties involved. Alternatives methods for defining the allocation are formulated. Generalized generation and load distribution factors for cost allocation are formulated and implemented. The methods are applied to allocate payments for transmission services provided by the transmission network and by a distribution company.

  15. Understanding ebola virus transmission.

    Science.gov (United States)

    Judson, Seth; Prescott, Joseph; Munster, Vincent

    2015-02-03

    An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus.

  16. Series Transmission Line Transformer

    Science.gov (United States)

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.

    2004-06-29

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  17. Atlas transmission line/transition design and fabrication status

    CERN Document Server

    Ballard, E O; Davis, H A; Elizondo, J M; Gribble, R F; Nielsen, K E; Parker, G V; Ricketts, R L; Valdez, G A

    1999-01-01

    Atlas is a pulsed-power facility under development at Los Alamos National Laboratory to drive high-energy density experiments. Design has been completed for this new generation pulsed-power machine consisting of an azimuthal array of 24, 240-kV Marx modules and transmission lines supplying current to the load region at the machine center. The transmission line consists of a cable header, load protection switch, and tri-plate assembly interfacing to the center transition section. The cable header interface to the Marx module provides a mechanism to remove the Marx module for maintenance without removing other components of the transmission line. The load protection switch provides a mechanism for protecting the load during charging of the Marx in the event of a pre-fire condition. The aluminum tri-plate is a low-inductance transmission line that carries radial current flow from the Marx energy storage system at the machine periphery toward the load. All transmission line components are oil insulated except the...

  18. Wireless Power Transmission Using Resonance Inductive Coupling

    Directory of Open Access Journals (Sweden)

    Prof. Vishal V. Pande,

    2014-04-01

    Full Text Available In this paper, we present the concept of transmitting power without using wires i.e.transmitting power as Magnetic waves from one place to another is in order to reduce the transmission and distribution losses. This concept is known as Resonance Inductive Coupling (RIC. We also discussed the technological developments in Wireless Power Transmission (WPT. The advantages, disadvantages, biological impacts and applications of WPT are also presented. Wireless power or wireless energy transmission is the transmission of electrical energy from a power source to an electrical load without man-made conductors. Wireless transmission is useful in cases where interconnecting wires are inconvenient, hazardous, or impossible. the proportion of energy received becomes critical only if it is too low for the signal to be distinguished from the background noise. With wireless power, efficiency is the more significant parameter. A large part of the energy sent out by the generating plant must arrive at the receiver or receivers to make the system economical.The most common form of wireless power transmission is carried out using direct induction followed by resonant magnetic induction. Other methods under consideration are electromagnetic radiation in the form of microwaves or lasers and electrical conduction through natural media

  19. Update: transmission of HIV-1 from mother to child.

    Science.gov (United States)

    Fowler, M G

    1997-12-01

    Mother-to-child transmission near the time of birth is the primary route of HIV-1 infection among infants and young children. Throughout the world, 1000 babies a day become infected with HIV, and cumulative global estimates are that 3 million children have been infected since the HIV pandemic began. Although major advances have been made in reducing mother-to-child transmission of HIV-1 in the USA and Europe through the use of an intensive regimen of zidovudine, many research questions remain unresolved. These include (1) viral and host characteristics which hinder or facilitate perinatal HIV transmission (i.e. the role played by viral load, the placenta and obstetric risk factors); (2) the proportion of transmission occurring in utero, intrapartum or during the breast feeding period; and (3) the mode of action of the successful zidovudine regimen. Studies published within the past year have shed light on several of these research topics. In 1996-1997 a number of important studies were published which support a general correlation between maternal viral load and infant HIV infection. The most recent studies do not, however, support the theory that there is a threshold below which transmission cannot occur, and also indicate that zidovudine, given according to the US Public Health Service guidelines, can significantly reduce the risk of transmission across all levels of maternal viral load. Analyses of viral load data from the successful clinical trial with zidovudine (AIDS Clinical Trial Group 076) suggest that its primary action is not by reducing the viral load, and raise the possibility that administering antiretroviral prophylaxis to the infant at the time of highest exposure may be another reason for the reduction in transmission. Obstetric risk factors for mother-to-child HIV transmission have been evaluated in several large cohort studies. A duration of membrane rupture of more than 4 h, and procedures such as amniocentesis, preterm labor, and the presence

  20. Poverty and price transmission

    DEFF Research Database (Denmark)

    Elleby, Christian

    A key parameter determining the welfare impact from a world market shock is the transmission elasticity which measures the average domestic response to an international price change. Many studies have estimated price transmission elasticities for a large number of countries but the variation in t...

  1. Cultural Transmission of Civicness

    DEFF Research Database (Denmark)

    Ljunge, Jan Martin

    This paper estimates the intergeneration transmission of civicness by studying second generation immigrants in 29 European countries with ancestry in 83 nations. There is significant transmission of civicness both on the mother’s and the father’s side. The estimates are quantitatively significant...

  2. Interspecies transmission of prions.

    Science.gov (United States)

    Afanasieva, E G; Kushnirov, V V; Ter-Avanesyan, M D

    2011-12-01

    Mammalian prions are infectious agents of proteinaceous nature that cause several incurable neurodegenerative diseases. Interspecies transmission of prions is usually impeded or impossible. Barriers in prion transmission are caused by small interspecies differences in the primary structure of prion proteins. The barriers can also depend on the strain (variant) of a transmitted prion. Interspecies barriers were also shown for yeast prions, which define some heritable phenotypes. Yeast prions reproduce all the main traits of prion transmission barriers observed for mammals. This allowed to show that the barrier in prion transmission can be observed even upon copolymerization of two prionogenic proteins. Available data allow elucidation of the mechanisms that impede prion transmission or make it impossible.

  3. Optimisation of power transmission systems using a discrete Tabu Search method

    OpenAIRE

    Connor, Andy M.; Tilley, Derek G.

    2016-01-01

    This paper presents a brief description of the Tabu Search method and shows how it can be applied to two different power transmission systems. Examples are presented from two transmission systems. In the first example a mechanical transmission system is considered. A four bar mechanism is synthesised in order to produce a desired output motion. The second example is a hydrostatic transmission operating under closed loop control in order to maintain a constant operating speed as the loading co...

  4. High Power Disk Loaded Guide Load

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, Z.D.; /SLAC

    2006-02-22

    A method to design a matching section from a smooth guide to a disk-loaded guide, using a variation of broadband matching, [1, 2] is described. Using this method, we show how to design high power loads. The load consists of a disk-loaded coaxial guide operating in the TE{sub 01}-mode. We use this mode because it has no electric field terminating on a conductor, has no axial currents, and has no current at the cylinder-disk interface. A high power load design that has -35 dB reflection and a 200 MHz, -20 dB bandwidth, is presented. It is expected that it will carry the 600 MW output peak power of the pulse compression network. We use coaxial geometry and stainless steel material to increase the attenuation per cell.

  5. An operational modal analysis approach based on parametrically identified multivariable transmissibilities

    Science.gov (United States)

    Devriendt, Christof; De Sitter, Gert; Guillaume, Patrick

    2010-07-01

    In this contribution the approach to identify modal parameters from output-only (scalar) transmissibility measurements [C. Devriendt, P. Guillaume, The use of transmissibility measurements in output-only modal analysis, Mechanical Systems and Signal Processing 21 (7) (2007) 2689-2696] is generalized to multivariable transmissibilities. In general, the poles that are identified from (scalar as well as multivariable) transmissibility measurements do not correspond with the system's poles. However, by combining transmissibility measurements under different loading conditions, it is shown in this paper how model parameters can be identified from multivariable transmissibility measurements.

  6. Understanding Ebola Virus Transmission

    Directory of Open Access Journals (Sweden)

    Seth Judson

    2015-02-01

    Full Text Available An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus.

  7. Tractor Transmissions. A Teaching Reference.

    Science.gov (United States)

    American Association for Agricultural Engineering and Vocational Agriculture, Athens, GA.

    The manual was developed as a reference for teaching students about transmissions in farm tractors. The manual is divided into five sections: (1) transmission history, (2) gears and bearings in transmission, (3) sliding-gear transmissions, (4) planetary gearing, and (5) glossary. The working principles of the sliding-gear transmission, the most…

  8. Transmission Cost Allocation Methodologies for Regional Transmission Organizations

    Energy Technology Data Exchange (ETDEWEB)

    Fink, S.; Rogers, J.; Porter, K.

    2010-07-01

    This report describes transmission cost allocation methodologies for transmission projects developed to maintain or enhance reliability, to interconnect new generators, or to access new resources and enhance competitive bulk power markets, otherwise known as economic transmission projects.

  9. The sound transmission of finite ribbed plates using a variational

    DEFF Research Database (Denmark)

    Brunskog, Jonas

    2012-01-01

    Many lightweight structures consist of plates being stiffened by ribs. The rib stiffeners can significantly change the vibration field and the radiation behavior of the structure. These type of structures has thus often been studied in the past. However, there is a lack of simplified expressions...... for the sound transmission of these structures. Therefore, simplified expressions for the sound transmission of finite single leaf ribbed plates are derived, using a variational technique based on integral equations of the fluid loaded plate....

  10. Optimized Information Transmission Scheduling Strategy Oriented to Advanced Metering Infrastructure

    OpenAIRE

    Weiming Tong; Xianji Jin; Lei Lu

    2013-01-01

    Advanced metering infrastructure (AMI) is considered to be the first step in constructing smart grid. AMI allows customers to make real-time choices about power utilization and enables power utilities to increase the effectiveness of the regional power grids by managing demand load during peak times and reducing unneeded power generation. These initiatives rely heavily on the prompt information transmission inside AMI. Aiming at the information transmission problem, this paper researches the ...

  11. Transmissions in vehicles 2010

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    Directory of Open Access Journals (Sweden)

    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

  13. Watching Handball Transmissions

    DEFF Research Database (Denmark)

    Frandsen, Kirsten

    2010-01-01

    , due to the dramaturgic structure of handball transmissions, viewers consider such transmissions particularly reliable and effective sources of entertainment. The transmissions’ entertainment value derives from their specific ability to give the viewers a complex experience of feeling autonomous...... and competent when mastering the game and in relation to others. The study shows that entertainment concerns both affective involvement and identity formation, as social and cultural meaning seem to be at the root of involvement. Even though both men and women find great joy in the transmissions, their viewing...... is embedded in quite diverse patterns regarding additional media use. This points to gendered differences regarding how the entertaining experience is basically received and the qualities sought and pursued in the transmissions....

  14. Electric Power Transmission Lines

    Data.gov (United States)

    Department of Homeland Security — Transmission Lines are the system of structures, wires, insulators and associated hardware that carry electric energy from one point to another in an electric power...

  15. Transmission of bilharziasis

    Science.gov (United States)

    Webbe, G.

    1965-01-01

    Accurate quantitative assessment is essential to any study of disease transmission; in relation to the transmission of bilharziasis the most important characteristics that have to be determined include density, reproduction and mortality rates, the age and sex structure of the population, dispersion and the intrinsic rate of natural increase (the biotic potential). The author discusses techniques that have been developed to yield this and other information and stresses the need to evaluate such techniques objectively. Some basic principles of population ecology are defined and discussed in relation to the control of transmission. It is considered that laboratory studies can be usefully carried on in conjunction with field work but that they cannot be substituted for field investigations in determining the parameters of bilharziasis transmission for a given area. PMID:5294586

  16. Kansas Electric Transmission Lines

    Data.gov (United States)

    Kansas Data Access and Support Center — This data set is a digital representation of the EletcircTransmission lines for the State of Kansas as maintained by the Kansas Corporation Commission. Data is...

  17. Transmission of Mumps

    Science.gov (United States)

    ... Serology Publications and Resources Multimedia MMWR Articles Outbreak Articles Related Links World Health Organization Medline Plus Transmission of Mumps Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir ...

  18. Down hole transmission system

    Science.gov (United States)

    Hall, David R.; Hall, Jr., H. Tracy

    2007-07-24

    A transmission system in a downhole component comprises a data transmission element in both ends of the downhole component. Each data transmission element houses an electrically conducting coil in a MCEI circular trough. The electrically conducting coil comprises at least two generally fractional loops. In the preferred embodiment, the transmission elements are connected by an electrical conductor. Preferably, the electrical conductor is a coaxial cable. Preferably, the MCEI trough comprises ferrite. In the preferred embodiment, the fractional loops are connected by a connecting cable. In one aspect of the present invention, the connecting cable is a pair of twisted wires. In one embodiment the connecting cable is a shielded pair of twisted wires. In another aspect of the present invention, the connecting cable is a coaxial cable. The connecting cable may be disposed outside of the MCEI circular trough.

  19. Lightening the Load

    OpenAIRE

    Remington, Anna M.; Swettenham, John G.; Lavie, Nilli

    2012-01-01

    Autism spectrum disorder (ASD) research portrays a mixed picture of attentional abilities with demonstrations of enhancements (e.g., superior visual search) and deficits (e.g., higher distractibility). Here we test a potential resolution derived from the Load Theory of Attention (e.g., Lavie, 2005). In Load Theory, distractor processing depends on the perceptual load of the task and as such can only be eliminated under high load that engages full capacity. We hypothesize that ASD involves enh...

  20. Eliminating Perinatal HIV Transmission

    Centers for Disease Control (CDC) Podcasts

    2012-11-26

    In this podcast, CDC’s Dr. Steve Nesheim discusses perinatal HIV transmission, including the importance of preventing HIV among women, preconception care, and timely HIV testing of the mother. Dr. Nesheim also introduces the revised curriculum Eliminating Perinatal HIV Transmission intended for faculty of OB/GYN and pediatric residents and nurse midwifery students.  Created: 11/26/2012 by Division of HIV/AIDS Prevention.   Date Released: 11/26/2012.

  1. Taking a Load Off.

    Science.gov (United States)

    Kenny, John

    1995-01-01

    Discusses the snow -load capacity of school roofs and how understanding this data aids in planning preventive measures and easing fear of roof collapse. Describes how to determine snow-load capacity, and explains the load-bearing behavior of flat versus sloped roofs. Collapse prevention measures are highlighted. (GR)

  2. 77 FR 6554 - Zephyr Power Transmission, LLC; Pathfinder Power Transmission, LLC; Duke-American Transmission...

    Science.gov (United States)

    2012-02-08

    ... Energy Regulatory Commission Zephyr Power Transmission, LLC; Pathfinder Power Transmission, LLC; Duke... (Commission), 18 CFR 381.302, Zephyr Power Transmission, LLC (Zephyr), Pathfinder Power Transmission, LLC (PPT... to exercise its negotiated rate authority for Zephyr Power Transmission Project; (2) that...

  3. National transmission grid study

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, Spencer [USDOE Office of the Secretary of Energy, Washington, DC (United States)

    2003-05-31

    The National Energy Policy Plan directed the U.S. Department of Energy (DOE) to conduct a study to examine the benefits of establishing a national electricity transmission grid and to identify transmission bottlenecks and measures to address them. DOE began by conducting an independent analysis of U.S. electricity markets and identifying transmission system bottlenecks using DOE’s Policy Office Electricity Modeling System (POEMS). DOE’s analysis, presented in Section 2, confirms the central role of the nation’s transmission system in lowering costs to consumers through increased trade. More importantly, DOE’s analysis also confirms the results of previous studies, which show that transmission bottlenecks and related transmission system market practices are adding hundreds of millions of dollars to consumers’ electricity bills each year. A more detailed technical overview of the use of POEMS is provided in Appendix A. DOE led an extensive, open, public input process and heard a wide range of comments and recommendations that have all been considered.1 More than 150 participants registered for three public workshops held in Detroit, MI (September 24, 2001); Atlanta, GA (September 26, 2001); and Phoenix, AZ (September 28, 2001).

  4. The Role of Demand Resources In Regional Transmission Expansion Planning and Reliable Operations

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, Brendan J [ORNL

    2006-07-01

    Investigating the role of demand resources in regional transmission planning has provided mixed results. On one hand there are only a few projects where demand response has been used as an explicit alternative to transmission enhancement. On the other hand there is a fair amount of demand response in the form of energy efficiency, peak reduction, emergency load shedding, and (recently) demand providing ancillary services. All of this demand response reduces the need for transmission enhancements. Demand response capability is typically (but not always) factored into transmission planning as a reduction in the load which must be served. In that sense demand response is utilized as an alternative to transmission expansion. Much more demand response is used (involuntarily) as load shedding under extreme conditions to prevent cascading blackouts. The amount of additional transmission and generation that would be required to provide the current level of reliability if load shedding were not available is difficult to imagine and would be impractical to build. In a very real sense demand response solutions are equitably treated in every region - when proposed, demand response projects are evaluated against existing reliability and economic criteria. The regional councils, RTOs, and ISOs identify needs. Others propose transmission, generation, or responsive load based solutions. Few demand response projects get included in transmission enhancement plans because few are proposed. But this is only part of the story. Several factors are responsible for the current very low use of demand response as a transmission enhancement alternative. First, while the generation, transmission, and load business sectors each deal with essentially the same amount of electric power, generation and transmission companies are explicitly in the electric power business but electricity is not the primary business focus of most loads. This changes the institutional focus of each sector. Second

  5. Transmission pricing and renewables: Issues, options, and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Stoft, S.; Webber, C.; Wiser, R.

    1997-05-01

    Open access to the transmission system, if provided at reasonable costs, should open new electricity markets for high-quality renewable resources that are located far from load centers. Several factors will affect the cost of transmission service, including the type of transmission pricing system implemented and the specific attributes of renewable energy. One crucial variable in the transmission cost equation is a generator`s capacity factor. This factor is important for intermittent renewables such as wind and solar, because it can increase transmission costs several fold due to the traditional use of take-or-pay, capacity-based transmission access charges. This report argues that such a charge is demonstrably unfair to renewable generators. It puts them at an economic disadvantage that will lead to an undersupply of renewable energy compared with the least-cost mix of generation technologies. The authors argue that congestion charges must first be separated from the access charges that cover the fixed cost of the network before one can design an efficient tariff. They then show that, in a competitive market with a separate charge for congestion, a take-or-pay capacity-based access charge used to cover system fixed costs cannot be justified on the basis of peak-load pricing. An energy-based access charge, on the other hand, is fair to intermittent generators as well as to the usual spectrum of peak and base-load technologies. This report also reviews other specific characteristics of renewables that can affect the cost of transmission, and evaluates the potential impact on renewables of several transmission pricing schemes, including postage-stamp rates, megawatt-mile pricing, congestion pricing, and the Federal Energy Regulatory Commission`s {open_quotes}point-to-point{close_quotes} transmission tariffs.

  6. Transmission pricing and renewables: Issues, options, and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Stoft, S.; Webber, C.; Wiser, R.

    1997-05-01

    Open access to the transmission system, if provided at reasonable costs, should open new electricity markets for high-quality renewable resources that are located far from load centers. Several factors will affect the cost of transmission service, including the type of transmission pricing system implemented and the specific attributes of renewable energy. One crucial variable in the transmission cost equation is a generator`s capacity factor. This factor is important for intermittent renewables such as wind and solar, because it can increase transmission costs several fold due to the traditional use of take-or-pay, capacity-based transmission access charges. This report argues that such a charge is demonstrably unfair to renewable generators. It puts them at an economic disadvantage that will lead to an undersupply of renewable energy compared with the least-cost mix of generation technologies. The authors argue that congestion charges must first be separated from the access charges that cover the fixed cost of the network before one can design an efficient tariff. They then show that, in a competitive market with a separate charge for congestion, a take-or-pay capacity-based access charge used to cover system fixed costs cannot be justified on the basis of peak-load pricing. An energy-based access charge, on the other hand, is fair to intermittent generators as well as to the usual spectrum of peak and base-load technologies. This report also reviews other specific characteristics of renewables that can affect the cost of transmission, and evaluates the potential impact on renewables of several transmission pricing schemes, including postage-stamp rates, megawatt-mile pricing, congestion pricing, and the Federal Energy Regulatory Commission`s {open_quotes}point-to-point{close_quotes} transmission tariffs.

  7. Spatial electric load forecasting

    CERN Document Server

    Willis, H Lee

    2002-01-01

    Spatial Electric Load Forecasting Consumer Demand for Power and ReliabilityCoincidence and Load BehaviorLoad Curve and End-Use ModelingWeather and Electric LoadWeather Design Criteria and Forecast NormalizationSpatial Load Growth BehaviorSpatial Forecast Accuracy and Error MeasuresTrending MethodsSimulation Method: Basic ConceptsA Detailed Look at the Simulation MethodBasics of Computerized SimulationAnalytical Building Blocks for Spatial SimulationAdvanced Elements of Computerized SimulationHybrid Trending-Simulation MethodsAdvanced

  8. Strategic Generation with Conjectured Transmission Price Responses in a Mixed Transmission Pricing System. Part 1. Formulation

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, B.F. [Department of Geography and Environmental Engineering, The Johns Hopkins University, Baltimore, MD (United States); Rijkers, F.A.M. [Office of Energy Regulation DTe, Den Haag (Netherlands)

    2004-05-01

    The conjectured supply function (CSF) model calculates an oligopolistic equilibrium among competing generating companies (GenCos), presuming that GenCos anticipate that rival firms will react to price increases by expanding their sales at an assumed rate. The CSF model is generalized here to include each generator's conjectures concerning how the price of transmission services (point-to-point service and constrained interfaces) will be affected by the amount of those services that the generator demands. This generalization reflects the market reality that large producers will anticipate that they can favorably affect transmission prices by their actions. The model simulates oligopolistic competition among generators while simultaneously representing a mixed transmission pricing system. This mixed system includes fixed transmission tariffs, congestion-based pricing of physical transmission constraints (represented as a linearized dc load flow), and auctions of interface capacity in a path-based pricing system. Pricing inefficiencies, such as export fees and no credit for counterflows, can be simulated. The model is formulated as a linear mixed complementarity problem, which enables very large market models to be solved. In the second paper of this two-paper series, the capabilities of the model are illustrated with an application to northwest Europe, where transmission pricing is based on such a mixture of approaches.

  9. BERTHA: A versatile transmission line and circuit code

    Science.gov (United States)

    Hinshelwood, D. D.

    1983-11-01

    An improved version of the NRL transmission line code of W. H. Lupton is presented. The capabilities of the original program were extended to allow magnetically insulated transmission lines, plasma opening switches, imploding plasma loads and discrete element electrical networks, for example, to be modeled. BERTHA is used to simulate any system that is represented by a configuration of transmission line elements. The electrical behavior of the system is calculated by repeatedly summing the reflected and transmitted waves at the ends of each element. This program is versatile, easy to use and easily implemented on desktop microcomputers.

  10. Dynamics of a split torque helicopter transmission

    Science.gov (United States)

    Rashidi, Majid; Krantz, Timothy

    A high reduction ratio split torque gear train has been proposed as an alternative to a planetary configuration for the final stage of a helicopter transmission. A split torque design allows a high ratio of power-to-weight for the transmission. The design studied in this work includes a pivoting beam that acts to balance thrust loads produced by the helical gear meshes in each of two parallel power paths. When the thrust loads are balanced, the torque is split evenly. A mathematical model was developed to study the dynamics of the system. The effects of time varying gear mesh stiffness, static transmission errors, and flexible bearing supports are included in the model. The model was demonstrated with a test case. Results show that although the gearbox has a symmetric configuration, the simulated dynamic behavior of the first and second compound gears are not the same. Also, results show that shaft location and mesh stiffness tuning are significant design parameters that influence the motions of the system.

  11. Effect of extended tooth contact on the modeling of spur gear transmissions

    Science.gov (United States)

    Oswald, Fred B.; Coy, John J.; Lin, Hsiang Hsi; Wang, Jifeng

    1993-01-01

    In some gear dynamic models, the effect of tooth flexibility is ignored when the model determines which pairs of teeth are in contact. Deflection of loaded teeth is not introduced until the equations of motion are solved. This means the zone of tooth contact and average tooth meshing stiffness are underestimated and the individual tooth load is overstated, especially for heavily-loaded gears. The static transmission error and dynamic load of heavily-loaded, low-contact-ratio spur gears is compared with this effect both neglected and included. Neglecting the effect yields an underestimate of resonance speeds and an overestimate of the dynamic load.

  12. Effect of extended tooth contact on the modeling of spur gear transmissions

    Science.gov (United States)

    Lin, Hsiang H.; Wang, Jifeng; Oswald, Fred B.; Coy, John J.

    1993-06-01

    In some gear dynamic models, the effect of tooth flexibility is ignored when the model determines which pairs of teeth are in contact. Deflection of loaded teeth is not introduced until the equations of motion are solved. This means the zone of tooth contact and average tooth meshing stiffness are underestimated and the individual tooth load is overstated, especially for heavily-loaded gears. The static transmission error and dynamic load of heavily-loaded, low-contact-ratio spur gears is compared with this effect both neglected and included. Neglecting the effect yields an underestimate of resonance speeds and an overestimate of the dynamic load.

  13. Duration of load revisited

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Sørensen, John Dalsgaard

    2007-01-01

    were formed. Four groups were subjected to short-term strength tests, and four groups were subjected to long-term tests. Creep and time to failure were moni-tored. Time to failure as a function of stress level was established and the reliability of stress level assessment was discussed. A significant...... mechanosorptive effect was demonstrated both in terms of increased creep and shortening of time to failure. The test results were employed for the calibration of four existing duration of load models. The effect of long-term loading was expressed as the stress level SL50 to cause failure after 50 years of loading...... and of the short-term and long-term strengths. For permanent and imposed library loads, reliability-based estimation of the load duration factor gave almost the same results as direct, deterministic calibration. Keywords: Creep, damage models, duration of load, equal rank assumption, load duration factor, matched...

  14. Soil compaction: Evaluation of stress transmission and resulting soil structure

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Schjønning, Per; Keller, Thomas;

    and compaction-resulted soil structure at the same time. Stress transmission was quantified using both X-ray CT and Tactilus sensor mat, and soil-pore structure was quantified using X-ray CT. Our results imply that stress transmission through soil highly depends on the magnitude of applied load and aggregate......, as a result stress transmission mode was shifted from discrete towards more like a continuum. Continuum-like stress transmission mode was better simulated with Boussinesq (1885) model based on theory of elasticity compared to discrete. The soil-pore structure was greatly affected by increasing applied......Accurate estimation of stress transmission and resultant deformation in soil profiles is a prerequisite for the development of predictive models and decision support tools for preventing soil compaction. Numerous studies have been carried out on the effects of soil compaction, whilst relatively few...

  15. A Structure Innovation on the Loading/Unloading Equipment for MSW Container

    Institute of Scientific and Technical Information of China (English)

    YANG Xianhai; LV Chuanyi

    2006-01-01

    A structure innovation on the loading/unloading equipment for MSW (municipal solid waste) container was designed. By disposing chain transmission perpendicularly, the loading/unloading equipment for MSW container was developed by linear movement part of the chain transmission. Effect of transmission mechanism on the motion stability of chain transmission was discussed. The relation between chain sag, chain length and chain pitch numbers was studied, and the calculation equation of chain sag by perpendicularly disposing chain transmission was deduced. The relation curve between allowed abrasion ratio and pitch numbers of chain was studied, the reason for tooth-leap was analyzed, and new equipment of preventing tooth-leap was put forward. Loading/unloading devices equipped with new transmission mechanism have been made into products, and this structure innovation has been applied in practice largely. It made considerable economic and social benefit.

  16. Ultrahigh Transmission Optical Nanofibers

    CERN Document Server

    Hoffman, J E; Grover, J A; Solano, P; Kordell, P R; Wong-Campos, J D; Orozco, L A; Rolston, S L

    2014-01-01

    We present a procedure for reproducibly fabricating ultrahigh transmission optical nanofibers (530 nm diameter and 84 mm stretch) with single-mode transmissions of 99.95 $ \\pm$ 0.02%, which represents a loss from tapering of 2.6 $\\,\\times \\,$ 10$^{-5}$ dB/mm when normalized to the entire stretch. When controllably launching the next family of higher-order modes on a fiber with 195 mm stretch, we achieve a transmission of 97.8 $\\pm$ 2.8%, which has a loss from tapering of 5.0 $\\,\\times \\,$ 10$^{-4}$ dB/mm when normalized to the entire stretch. Our pulling and transfer procedures allow us to fabricate optical nanofibers that transmit more than 400 mW in high vacuum conditions. These results, published as parameters in our previous work, present an improvement of two orders of magnitude less loss for the fundamental mode and an increase in transmission of more than 300% for higher-order modes, when following the protocols detailed in this paper. We extract from the transmission during the pull, the only reported...

  17. Bit Loading Algorithms for Cooperative OFDM Systems

    Directory of Open Access Journals (Sweden)

    Bo Gui

    2007-12-01

    Full Text Available We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  18. Bit Loading Algorithms for Cooperative OFDM Systems

    Directory of Open Access Journals (Sweden)

    Gui Bo

    2008-01-01

    Full Text Available Abstract We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  19. Optimisation of load control

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, P. [VTT Energy, Espoo (Finland)

    1998-08-01

    Electricity cannot be stored in large quantities. That is why the electricity supply and consumption are always almost equal in large power supply systems. If this balance were disturbed beyond stability, the system or a part of it would collapse until a new stable equilibrium is reached. The balance between supply and consumption is mainly maintained by controlling the power production, but also the electricity consumption or, in other words, the load is controlled. Controlling the load of the power supply system is important, if easily controllable power production capacity is limited. Temporary shortage of capacity causes high peaks in the energy price in the electricity market. Load control either reduces the electricity consumption during peak consumption and peak price or moves electricity consumption to some other time. The project Optimisation of Load Control is a part of the EDISON research program for distribution automation. The following areas were studied: Optimization of space heating and ventilation, when electricity price is time variable, load control model in power purchase optimization, optimization of direct load control sequences, interaction between load control optimization and power purchase optimization, literature on load control, optimization methods and field tests and response models of direct load control and the effects of the electricity market deregulation on load control. An overview of the main results is given in this chapter

  20. Probabilistic transmission system planning

    CERN Document Server

    Li, Wenyuan

    2011-01-01

    "The book is composed of 12 chapters and three appendices, and can be divided into four parts. The first part includes Chapters 2 to 7, which discuss the concepts, models, methods and data in probabilistic transmission planning. The second part, Chapters 8 to 11, addresses four essential issues in probabilistic transmission planning applications using actual utility systems as examples. Chapter 12, as the third part, focuses on a special issue, i.e. how to deal with uncertainty of data in probabilistic transmission planning. The fourth part consists of three appendices, which provide the basic knowledge in mathematics for probabilistic planning. Please refer to the attached table of contents which is given in a very detailed manner"--

  1. Aerosol Transmission of Filoviruses

    Directory of Open Access Journals (Sweden)

    Berhanu Mekibib

    2016-05-01

    Full Text Available Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire and Sudan, the 2013–2015 western African Ebola virus disease (EVD outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of aerosol transmission of filoviruses.

  2. Plasmon cross transmission

    Energy Technology Data Exchange (ETDEWEB)

    Dobrzynski, Leonard; Akjouj, Abdellatif; Li, Changsheng, E-mail: Abdellatif.Akjouj@univ-lille1.fr [Centre National de la Recherche Scientifique, Universite Lille Nord de France, Lille1, Institut d' Electronique, de Microelectronique et de Nanotechnologie, Unite de Physique, Batiment P5, 59655 Villeneuve d' Ascq Cedex (France)

    2011-09-14

    Plasmon cross transmission avoids the frontal collision between two plasmons traveling in opposite directions along a guide. The guide is made out of equidistant identical metal dots. Thanks to two resonator dots, the plasmon frontal impact is avoided by transmission of the two plasmons from the input guide to an output one. The resonator and guide dots are identical in size and metal composition. The dipole-dipole interactions are restricted to first nearest neighbors. A convenient metal doping is assumed to compensate exactly all attenuations. The parameters are the nearest neighbor distances between the dots. These distances are rescaled to the chain nearest neighbor distance d. The system has two symmetry mirror planes. This simple model enables us to obtain two analytic tuning relations for the plasmon cross transmission. The intensities of the transmitted signals versus kd, where k is the plasmon propagation vector, are also given. (paper)

  3. Aerosol Transmission of Filoviruses.

    Science.gov (United States)

    Mekibib, Berhanu; Ariën, Kevin K

    2016-05-23

    Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire) and Sudan, the 2013-2015 western African Ebola virus disease (EVD) outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s) in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of aerosol transmission of filoviruses.

  4. New Gear Transmission Error Measurement System Designed

    Science.gov (United States)

    Oswald, Fred B.

    2001-01-01

    The prime source of vibration and noise in a gear system is the transmission error between the meshing gears. Transmission error is caused by manufacturing inaccuracy, mounting errors, and elastic deflections under load. Gear designers often attempt to compensate for transmission error by modifying gear teeth. This is done traditionally by a rough "rule of thumb" or more recently under the guidance of an analytical code. In order for a designer to have confidence in a code, the code must be validated through experiment. NASA Glenn Research Center contracted with the Design Unit of the University of Newcastle in England for a system to measure the transmission error of spur and helical test gears in the NASA Gear Noise Rig. The new system measures transmission error optically by means of light beams directed by lenses and prisms through gratings mounted on the gear shafts. The amount of light that passes through both gratings is directly proportional to the transmission error of the gears. A photodetector circuit converts the light to an analog electrical signal. To increase accuracy and reduce "noise" due to transverse vibration, there are parallel light paths at the top and bottom of the gears. The two signals are subtracted via differential amplifiers in the electronics package. The output of the system is 40 mV/mm, giving a resolution in the time domain of better than 0.1 mm, and discrimination in the frequency domain of better than 0.01 mm. The new system will be used to validate gear analytical codes and to investigate mechanisms that produce vibration and noise in parallel axis gears.

  5. Poverty and price transmission

    DEFF Research Database (Denmark)

    Elleby, Christian

    A key parameter determining the welfare impact from a world market shock is the transmission elasticity which measures the average domestic response to an international price change. Many studies have estimated price transmission elasticities for a large number of countries but the variation in t...... growth but the relationship is less significant. The finding that food prices in middle-income countries increased the most during the food crises is a cause for concern in light of the fact that the majority of the world's poor today live in middle-income countries....

  6. Transmission grid security

    CERN Document Server

    Haarla, Liisa; Hirvonen, Ritva; Labeau, Pierre-Etienne

    2011-01-01

    In response to the growing importance of power system security and reliability, ""Transmission Grid Security"" proposes a systematic and probabilistic approach for transmission grid security analysis. The analysis presented uses probabilistic safety assessment (PSA) and takes into account the power system dynamics after severe faults. In the method shown in this book the power system states (stable, not stable, system breakdown, etc.) are connected with the substation reliability model. In this way it is possible to: estimate the system-wide consequences of grid faults; identify a chain of eve

  7. DATA TRANSMISSION INVESTIGATION

    Science.gov (United States)

    modem will have the capability of 18 bit rates and will be used in the investigation of the short range HF data transmission. System block diagrams of...Field test results of various modems operating over the AN/VRC-12 radio set are presented. Map profiles of each data link are shown and the average...error rates are given for digital data transmission at rates from 300 to 4800 bps. Bit error rates vary depending upon the site and bit rate. The

  8. Transmission positron microscopes

    Energy Technology Data Exchange (ETDEWEB)

    Doyama, Masao [Teikyo University of Science and Technology, Uenohara, Yamanashi 409-0193 (Japan)]. E-mail: doyama@ntu.ac.jp; Kogure, Yoshiaki [Teikyo University of Science and Technology, Uenohara, Yamanashi 409-0193 (Japan); Inoue, Miyoshi [Teikyo University of Science and Technology, Uenohara, Yamanashi 409-0193 (Japan); Kurihara, Toshikazu [Institute of Materials Structure Science (IMSS), High Energy Accelerator, Research Organization (KEK), Ohno 1-1, Tsukuba, Ibaraki 305-0801 (Japan); Yoshiie, Toshimasa [Reactor Research Institute, Kyoto University, Noda, Kumatori, Osaka 590-0451 (Japan); Oshima, Ryuichiro [Research Institute for Advanced Science and Technology, Osaka Prefecture University (Japan); Matsuya, Miyuki [Electron Optics Laboratory (JEOL) Ltd., Musashino 3-1-2, Akishima 196-0021 (Japan)

    2006-02-28

    Immediate and near-future plans for transmission positron microscopes being built at KEK, Tsukuba, Japan, are described. The characteristic feature of this project is remolding a commercial electron microscope to a positron microscope. A point source of electrons kept at a negative high voltage is changed to a point source of positrons kept at a high positive voltage. Positional resolution of transmission microscopes should be theoretically the same as electron microscopes. Positron microscopes utilizing trapping of positrons have always positional ambiguity due to the diffusion of positrons.

  9. Reinforcing Power Grid Transmission with FACTS Devices

    CERN Document Server

    Frolov, Vladimir; Chertkov, Misha

    2013-01-01

    We explore optimization methods for planning the placement, sizing and operations of Flexible Alternating Current Transmission System (FACTS) devices installed into the grid to relieve congestion created by load growth or fluctuations of intermittent renewable generation. We limit our selection of FACTS devices to those that can be represented by modification of the inductance of the transmission lines. Our master optimization problem minimizes the $l_1$ norm of the FACTS-associated inductance correction subject to constraints enforcing that no line of the system exceeds its thermal limit. We develop off-line heuristics that reduce this non-convex optimization to a succession of Linear Programs (LP) where at each step the constraints are linearized analytically around the current operating point. The algorithm is accelerated further with a version of the cutting plane method greatly reducing the number of active constraints during the optimization, while checking feasibility of the non-active constraints post...

  10. Transmission of Electric Energy Along Long Lines

    Directory of Open Access Journals (Sweden)

    Berzan V.P.

    2009-08-01

    Full Text Available Transmission of electric energy along long lines is examined and characteristics of the change of capacities at the beginning and at the end of a line are submitted: factor of capacity, efficiency of a transmission line, currents depending on length, parameters of a line and parameters of loading. Influence of losses upon the dynamics of instant values of voltages and currents in the opened and short-circuited long lines is investigated and effects of nonlinearity in such chains are revealed at a power supply from a sinusoidal source of voltage. It is shown, that the method of complex amplitudes is not always applicable for the calculation of modes in long lines.

  11. TRANSMISSION OF NOROVIRUS WITHIN HOUSEHOLDS IN QUININDE, ECUADOR

    OpenAIRE

    Gastañaduy, Paul A.; Vicuña, Yosselin; Salazar, Fabian; Broncano, Nely; Gregoricus, Nicole; Vinjé, Jan; Chico,Martha; Parashar, Umesh D; Cooper,Philip J; Lopman, Ben

    2015-01-01

    We studied the transmission of norovirus infection in households in Quininde, Ecuador. Among household contacts of norovirus positive children with diarrhea, norovirus negative children with diarrhea and asymptomatic controls, infection attack rates were 33%, 8% and 18%, respectively (N = 45, 36, 83). Infection attack rates were higher when index children had a higher viral load.

  12. Transmission of Norovirus Within Households in Quininde, Ecuador.

    Science.gov (United States)

    Gastañaduy, Paul A; Vicuña, Yosselin; Salazar, Fabian; Broncano, Nely; Gregoricus, Nicole; Vinjé, Jan; Chico, Martha; Parashar, Umesh D; Cooper, Philip J; Lopman, Ben

    2015-09-01

    We studied the transmission of norovirus infection in households in Quininde, Ecuador. Among household contacts of norovirus positive children with diarrhea, norovirus negative children with diarrhea and asymptomatic controls, infection attack rates were 33%, 8% and 18%, respectively (N = 45, 36, 83). Infection attack rates were higher when index children had a higher viral load.

  13. Integrated Fractional Load and Packet Scheduling for OFDMA Systems

    DEFF Research Database (Denmark)

    Monghal, Guillaume Damien; Kumar, S.; Pedersen, Klaus I.

    2009-01-01

    This paper study the performance of an orthogonal frequency division multiple access (OFDMA) system under fractional load based in long term evolution (LTE) downlink. Fractional load is defined by a situation where only a fraction of the bandwidth is used for transmission due to lack of traffic....... This type of situation should result in a global increase of signal to interference and noise ratio (SINR) conditions in the network. We propose different methods integrating the transmission pattern selection to the packet scheduling functionality of the enode-B depending only on the channel quality...... indicator (CQI) reports from the user equipments. Fractional load handling is operated without inter eNode-B coordination. We conclude that the system can operate under fractional load conditions if the CQI is calculated with wideband interference. Further gain can be obtained if the CQI is calculated...

  14. Anchor Loads on Pipelines

    OpenAIRE

    Wei, Ying

    2015-01-01

    Anchor hooking on a subsea pipeline has been investigated in this thesis. Anchor loads on pipelines is in general a rarely occurring event, however, the severity when it occurs could easily jeopardize the integrity of any pipeline. It is considered as an accidental load in the design of pipelines. Pipeline Loads, limit state criteria and anchor categories are defined by the DNV standards. For pipeline, DNV-OS-F101 (08.2012), Submarine Pipeline Systems is adopted. Offshore standard DNV-RP...

  15. Load induced blindness

    OpenAIRE

    Macdonald, J. S. P.; Lavie, N.

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied oil indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005. for a review). Here we varied the level of perceptual load in a letter-search task and assessed its effect oil the conscious perception of a search-irrelevant shape stimulus appearing in the pe...

  16. The interplay between wind turbines and CPH plants and effects on transmission grid requirements

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2003-01-01

    The article analyses power flows in the transmission system with scattered load balancing under various climatic conditions with uneven distributions of wind power and uneven temperature and thus CHP conditions in the country.......The article analyses power flows in the transmission system with scattered load balancing under various climatic conditions with uneven distributions of wind power and uneven temperature and thus CHP conditions in the country....

  17. Optimized Minimal Inductance Transmission Line Configuration for Z-Pinch Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hurricane, O

    2003-10-16

    Successful dynamic Z-pinch experiments generally require good current delivery to the target load. Power flow losses through highly inductive transmission line configurations reduce the current available to the load. In this Brief Report, a variational calculus technique is used to determine the transmission line configuration that produces the least possible inductance and therefore the best possible current delivery for Z-pinch experiments.

  18. Optimized Minimal Inductance Transmission Line Configuration for Z-Pinch Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hurricane, O

    2003-10-16

    Successful dynamic Z-pinch experiments generally require good current delivery to the target load. Power flow losses through highly inductive transmission line configurations reduce the current available to the load. In this Brief Report, a variational calculus technique is used to determine the transmission line configuration that produces the least possible inductance and therefore the best possible current delivery for Z-pinch experiments.

  19. Switching in electrical transmission and distribution systems

    CERN Document Server

    Smeets, René; Kapetanovic, Mirsad; Peelo, David F; Janssen, Anton

    2014-01-01

    Switching in Electrical Transmission and Distribution Systems presents the issues and technological solutions associated with switching in power systems, from medium to ultra-high voltage. The book systematically discusses the electrical aspects of switching, details the way load and fault currents are interrupted, the impact of fault currents, and compares switching equipment in particular circuit-breakers. The authors also explain all examples of practical switching phenomena by examining real measurements from switching tests. Other highlights include: up to date commentary on new develo

  20. Concentrated loads on concrete

    DEFF Research Database (Denmark)

    Lorenzen, Karen Grøndahl; Nielsen, Mogens Peter

    1997-01-01

    This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas are devel......This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas...

  1. Concentrated loads on concrete

    DEFF Research Database (Denmark)

    Lorenzen, Karen Grøndahl; Nielsen, Mogens Peter

    1997-01-01

    This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas are devel......This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas...

  2. Critical Axial Load

    Directory of Open Access Journals (Sweden)

    Walt Wells

    2008-01-01

    Full Text Available Our objective in this paper is to solve a second order differential equation for a long, simply supported column member subjected to a lateral axial load using Heun's numerical method. We will use the solution to find the critical load at which the column member will fail due to buckling. We will calculate this load using Euler's derived analytical approach for an exact solution, as well as Euler's Numerical Method. We will then compare the three calculated values to see how much they deviate from one another. During the critical load calculation, it will be necessary to calculate the moment of inertia for the column member.

  3. Electrical load modeling

    Energy Technology Data Exchange (ETDEWEB)

    Valgas, Helio Moreira; Pinto, Roberto del Giudice R.; Franca, Carlos [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Lambert-Torres, Germano; Silva, Alexandre P. Alves da; Pires, Robson Celso; Costa Junior, Roberto Affonso [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    Accurate dynamic load models allow more precise calculations of power system controls and stability limits, which are critical mainly in the operation planning of power systems. This paper describes the development of a computer program (software) for static and dynamic load model studies using the measurement approach for the CEMIG system. Two dynamic load model structures are developed and tested. A procedure for applying a set of measured data from an on-line transient recording system to develop load models is described. (author) 6 refs., 17 figs.

  4. Stress transmission in soil

    DEFF Research Database (Denmark)

    Lamandé, Mathieu; Schjønning, Per

    . The tests took place in the spring at field capacity when the topsoil had not been tilled for 1½ year. Two Nokian ELS Radial-ply tyres (800/50R34 and 560/45R22.5) were loaded with two specific loads (30 kN and 60 kN). We used rated tyre inflation pressures for traffic in the field (≤10 km h-1 driving speed...... the soil-tyre interface were measured in separate tests by 17 stress transducers across the width of the tyres. The results showed that the inflation pressure controlled the level of maximum stresses at 0.3 m depth, while the wheel load was correlated to the measured stresses at 0.9 m depth. This supports...

  5. Laser power transmission

    Science.gov (United States)

    Conway, Edmund J.

    1992-01-01

    An overview of previous studies related to laser power transmission is presented. Particular attention is given to the use of solar pumped lasers for space power applications. Three general laser mechanisms are addressed: photodissociation lasing driven by sunlight, photoexcitation lasing driven directly by sunlight, and photoexcitation lasing driven by thermal radiation.

  6. Intergenerational Transmission of Volunteering

    NARCIS (Netherlands)

    Bekkers, René

    2007-01-01

    In this article, I investigate the strength of intergenerational transmission of volunteering for non-profit associations in The Netherlands. Data from the Family Survey of the Dutch Population 2000 reveal that there are significant relations between current volunteering and parental volunteering in

  7. Facsimile Transmission Standards

    Science.gov (United States)

    1993-10-01

    transmettre les cartes tactiques et les compte rendu de situation. La presente note technique expose les 6lements nec~ssaires A la transmission de t~l6copies...Group MI machines introduced digital scanning techniques in which the single photoelectric cell was replaced with a Charged Coupled Device (CCD) array

  8. Dilemmas of Cultural Transmission

    Science.gov (United States)

    Kováts-Németh, Mária

    2016-01-01

    The fundamental problem of the 21st century is that in the modern civilization "the transmission of values is not stable." There is nothing, except for the natural sense of justice and some legal traditions, which would exercise selective power on social behavior. At a critical time in 1949 Albert Szent-Györgyi drew the attention to the…

  9. Intergenerational Transmission of Volunteering

    NARCIS (Netherlands)

    Bekkers, René

    2007-01-01

    In this article, I investigate the strength of intergenerational transmission of volunteering for non-profit associations in The Netherlands. Data from the Family Survey of the Dutch Population 2000 reveal that there are significant relations between current volunteering and parental volunteering in

  10. Propagation along azimuthally magnetized ferrite-loaded circular waveguides

    Science.gov (United States)

    Mueller, R. S.; Rosenbaum, F. J.

    1977-01-01

    The paper describes the modal dispersion characteristics of electromagnetic waves traveling along the azimuthally magnetized ferrite-loaded coaxial transmission line and the ferrite-loaded wire. The modal dispersion curves are used to determine the pass and stop bands of normal propagation. Boundary-value problems were solved with Bolle-Heller functions. The dispersion characteristics of transverse electric modes are presented as plots of the normalized propagation constant vs the normalized frequency.

  11. A model for voltage collapse study considering load characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, L.B. [Companhia de Energia Eletrica da Bahia (COELBA), Salvador, BA (Brazil)

    1994-12-31

    This paper presents a model for analysis of voltage collapse and instability problem considering the load characteristics. The model considers fundamentally the transmission lines represented by exact from through the generalized constants A, B, C, D and the loads as function of the voltage, emphasizing the cases of constant power, constant current and constant impedance. the study treats of the system behavior on steady state and presents illustrative graphics about the problem. (author) 12 refs., 4 figs.

  12. Influence of linear profile modification and loading conditions on the dynamic tooth load and stress of high contact ratio gears

    Science.gov (United States)

    Lee, Chinwai; Lin, Hsiang Hsi; Oswald, Fred B.; Townsend, Dennis P.

    1990-01-01

    A computer simulation for the dynamic response of high-contact-ratio spur gear transmissions is presented. High contact ratio gears have the potential to produce lower dynamic tooth loads and minimum root stress but they can be sensitive to tooth profile errors. The analysis presented examines various profile modifications under realistic loading conditions. The effect of these modifications on the dynamic load (force) between mating gear teeth and the dynamic root stress is presented. Since the contact stress is dependent on the dynamic load, minimizing dynamic loads will also minimize contact stresses. It is shown that the combination of profile modification and the applied load (torque) carried by a gear system has a significant influence on gear dynamics. The ideal modification at one value of applied load will not be the best solution for a different load. High-contact-ratio gears were found to require less modification than standard low-contact-ratio gears. High-contact-ratio gears are more adversely affected by excess modification than by under modification. In addition, the optimal profile modification required to minimize the dynamic load (hence the contact stress) on a gear tooth differs from the optimal modification required to minimize the dynamic root (bending) stress. Computer simulation can help find the design tradeoffs to determine the best profile modification to satisfy the conflicting constraints of minimizing both the load and root stress in gears which must operate over a range of applied loads.

  13. Function of the medial meniscus in force transmission and stability.

    Science.gov (United States)

    Walker, Peter S; Arno, Sally; Bell, Christopher; Salvadore, Gaia; Borukhov, Ilya; Oh, Cheongeun

    2015-06-01

    We studied the combined role of the medial meniscus in distributing load and providing stability. Ten normal knees were loaded in combinations of compressive and shear loading as the knee was flexed over a full range. A digital camera tracked the motion, from which femoral-tibial contacts were determined by computer modelling. Load transmission was determined from the Tekscan for the anterior horn, central body, posterior horn, and the uncovered cartilage in the centre of the meniscus. For the three types of loading; compression only, compression and anterior shear, compression and posterior shear; between 40% and 80% of the total load was transmitted through the meniscus. The overall average was 58%, the remaining 42% being transmitted through the uncovered cartilage. The anterior horn was loaded only up to 30 degrees flexion, but played a role in controlling anterior femoral displacement. The central body was loaded 10-20% which would provide some restraint to medial femoral subluxation. Overall the posterior horn carried the highest percentage of the shear load, especially after 30 degrees flexion when a posterior shear force was applied, where the meniscus was estimated to carry 50% of the shear force. This study added new insights into meniscal function during weight bearing conditions, particularly its role in early flexion, and in transmitting shear forces.

  14. A Proposed Supergrid Model for National Transmission Network of Pakistan

    Directory of Open Access Journals (Sweden)

    FAHEEM AKHTER

    2017-01-01

    Full Text Available Pakistan is facing a severe energy crisis of its time with significant generation deficit in recent years. The future plan shows hydro and thermal coal generation as major contributor and Wind power to replace Thermal-oil generation in long run. This paper proposes a Super grid model for the transfer of bulk power from generation station to the load centres, which can provide efficient transmission between generation and load centres and is also adaptive to deal with variations in power from renewable generations. A dynamic simulation analysis is performed on six-terminal MTDC (Multi-Terminal High Voltage Direct Current system VSC (Voltage Source Converter based MTDC meshed grid with different control operations. The results show that the proposed super grid model can provide efficient transmission between generation and load centres and it is also adaptive to deal with variation in power from renewable generation.

  15. Optimal Placement and Sizing of FACTS Devices to Delay Transmission Expansion

    CERN Document Server

    Frolov, Vladimir; Backhaus, Scott; Bialek, Janusz; Chertkov, Michael

    2016-01-01

    The Transmission System Operators (TSOs) plan to reinforce their transmission grids based on the projected system congestion caused by the increase in future system load, amongst other factors. However, transmission expansion is severely limited in many countries, and especially in Europe, due to many factors such as clearance acquisitions. An alternative is to use Flexible Alternating Current Transmission System (FACTS) devices, thus allowing to delay or avoid much more expensive transmission expansion. These devices are capable of utilizing the existing transmission grid more flexibly. However, the locations and sizing of future FACTS devices must be carefully determined during the planning phase in order to avoid congestion under many representative scenarios of the projected economic growth (of loads). This paper proposes an optimization approach, based on AC Power Flows, to determine suitable locations and sizes of series and shunt FACTS devices. Non-linear, non-convex and multiple-scenario based optimiz...

  16. Combination of external loads

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, S.; Tarp Johansen, N.J.; Joergensen, H. [Forskningscenter Risoe, Roskilde (Denmark); Gravesen, H.; Soerensen, S.L. [Carl Bro, Glostrup (Denmark); Pedersen, J. [Elsam Engineering, Fredericia (Denmark); Zorn, R.; Hvidberg Knudsen, M. [DHI Water and Environment, Hoersholm (Denmark); Voelund, P. [Energi E2, Koebenhavn (Denmark)

    2003-09-01

    The project onbectives have been: To improve and consequently opimise the basis for design of offshore wind turbines. This is done through 1) mapping the wind, wave ice and current as well as correlations of these, and 2) by clarifyring how these external conditions transform into loads. A comprehensive effort has been made to get a thorough understanding of the uncertainties that govern the reliability of wind turbines with respect to wind and wave loading. One of the conclusions is that the reliability of wind turbines is generally lower, than the average reliability of building structures that are subject not only to environmental loads, which are very uncertain, but also imposed loads and self weight, which are less uncertain than the environmental loads. The implication is that, at the moment lower load partial safety factors for onshore wind turbines cannot be recommended. For the combination of wind and wave design loads the problem is twofold: 1). A very conservative design will be generated by simply adding the individual wind and wave design loads disregarding the independence of the short-term fluctuations of wind and wave loads. 2). Characteristic values and partial safety factors for wind and wave loads are not defined similarly. This implies that the reliability levels of turbine support structures subject to purely aerodynamic loads and subject to purely hydrodynamic loads are not identical. For the problem of combining aerodynamic design loads and hydrodynamic design loads two results have been obtained in the project: 1). By simple means a site specific wave load safety factor rendering the same safety level for hydrodynamic loads as for aerodynamic loads is derived, and next, by direct square summation of extreme fluctuations, the wind and wave load safety factors are weighted. 2). Under the assumptions that a deep water site is considered and that the wave loading is a fifty-fifty mix of drag and inertia the same wind and wave load safety factor

  17. Load Induced Blindness

    Science.gov (United States)

    Macdonald, James S. P.; Lavie, Nilli

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005, for a review). Here we varied the level of…

  18. Renewable Resource Integration Project - Scoping Study of Strategic Transmission, Operations, and Reliability Issues

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph; Budhraja, Vikram; Ballance, John; Dyer, Jim; Mobasheri, Fred; Eto, Joseph

    2008-07-01

    California is on a path to increase utilization of renewable resources. California will need to integrate approximately 30,000 megawatts (MW) of new renewable generation in the next 20 years. Renewable resources are typically located in remote locations, not near the load centers. Nearly two/thirds or 20,000 MW of new renewable resources needed are likely to be delivered to Los Angeles Basin transmission gateways. Integration of renewable resources requires interconnection to the power grid, expansion of the transmission system capability between the backbone power grid and transmission gateways, and increase in delivery capacity from transmission gateways to the local load centers. To scope the transmission, operations, and reliability issues for renewables integration, this research focused on the Los Angeles Basin Area transmission gateways where most of new renewables are likely. Necessary actions for successful renewables integration include: (1) Expand Los Angeles Basin Area transmission gateway and nomogram limits by 10,000 to 20,000 MW; (2) Upgrade local transmission network for deliverability to load centers; (3) Secure additional storage, demand management, automatic load control, dynamic pricing, and other resources that meet regulation and ramping needed in real time operations; (4) Enhance local voltage support; and (5) Expand deliverability from Los Angeles to San Diego and Northern California.

  19. Indentation load relaxation test

    Energy Technology Data Exchange (ETDEWEB)

    Hannula, S.P.; Stone, D.; Li, C.Y. (Cornell Univ., Ithaca, NY (USA))

    Most of the models that are used to describe the nonelastic behavior of materials utilize stress-strain rate relations which can be obtained by a load relaxation test. The conventional load relaxation test, however, cannot be performed if the volume of the material to be tested is very small. For such applications the indentation type of test offers an attractive means of obtaining data necessary for materials characterization. In this work the feasibility of the indentation load relaxation test is studied. Experimental techniques are described together with results on Al, Cu and 316 SS. These results are compared to those of conventional uniaxial load relaxation tests, and the conversion of the load-indentation rate data into the stress-strain rate data is discussed.

  20. Trust Aware Load Distribution in a Data Grid Environment

    Directory of Open Access Journals (Sweden)

    Ms. Shaik Naseera

    2010-01-01

    Full Text Available The basic idea of a load balance system is to transfer partial of system workload from busy nodes to some idle nodes. The target resource selection for task migration is a key factor in the load balance strategy. As grid is dynamic in nature, resources may join or leave the grid at any instance of time. It's inefficient to select a target resource that often leaves the grid and hence the tasks may be rescheduled for several times. When the cost of load transmission is not negligible, the overhead of the load balancing strategy will be unacceptable. In such dynamic grid environment, the cost of propagating system load will be extremely high. To improve the efficiency of the load balancing process, one can select trustworthy resources from the list of available resources. In this paper we present a load distribution strategy that considers the trustworthiness of the resource as a benchmark for participation in the load balancing process. The simulation results show that the load distribution among the trustworthy resources results better system throughput compared to load distribution to all available resources in the grid.

  1. Mechanisms, Transmissions and Applications

    CERN Document Server

    Corves, Burkhard

    2012-01-01

    The first Workshop on Mechanisms, Transmissions and Applications -- MeTrApp-2011 was organized by the Mechatronics Department at the Mechanical Engineering Faculty, “Politehnica” University of Timisoara, Romania, under the patronage of the IFToMM Technical Committees Linkages and Mechanical Controls and Micromachines. The workshop brought together researchers and students who work in disciplines associated with mechanisms science and offered a great opportunity for scientists from all over the world to present their achievements, exchange innovative ideas and create solid international links, setting the trend for future developments in this important and creative field. The topics treated in this volume are mechanisms and machine design, mechanical transmissions, mechatronic and biomechanic applications, computational and experimental methods, history of mechanism and machine science and teaching methods.

  2. Nonlinear Vibroimpact Characteristics of a Planetary Gear Transmission System

    Directory of Open Access Journals (Sweden)

    Jianxing Zhou

    2016-01-01

    Full Text Available In order to research the vibroimpact characteristics of a planetary gear transmission system under high speed and lightly loaded conditions, a new modeling method is proposed. In the modeling process, linear spring was used to simulate gear mesh elasticity under heavy load cases, and Hertz contact theory was used to calculate the contact force of gear pair under light load cases. Then, effects of the working conditions on the system vibroimpact characteristics are analyzed. The results show that, with input speed growing, the mesh force produced obvious fluctuations on the resonance frequencies of the sun gear and carrier torsion vibration, ring gear’s transverse vibration under the heavy load. Under light load condition, the collision vibration occurs in the gear pair; the changing trend of the contact force shows strongly nonlinear characteristics. The time of mesh-apart in gears pair decreases gradually as the load is increased; until it reaches collision vibration threshold value, the gear pair is no longer mesh-apart. With increasing of the input speed, the time of mesh-apart is decreased gradually; the fluctuation amplitude of contact force shows a linearly increasing trend. The study provides useful theoretical guideline for planetary gear transmission low-noise design.

  3. The Cost of Transmission for Wind Energy: A Review of Transmission Planning Studies

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Andrew D.; Wiser, Ryan; Porter, Kevin

    2009-02-02

    The rapid development of wind power that the United States has experienced over the last several years has been coupled with a growing concern that wind development will require substantial additions to the nation's transmission infrastructure. Transmission is particularly important for wind power due to the locational dependence of wind resources, the relatively low capacity factor of wind plants, and the mismatch between the short lead time to build a new wind project and the longer lead time often needed to plan, permit, and construct transmission. It is clear that institutional issues related to transmission planning, siting, and cost allocation will pose major obstacles to accelerated wind power deployment, but also of concern is the potential cost of this infrastructure build out. Simply put, how much extra cost will society bear to deliver wind power to load centers? Without an answer to this question, there can be no consensus on whether or not the cost of developing transmission for wind will be a major barrier to further wind deployment, or whether the institutional barriers to transmission expansion are likely to be of more immediate concern. In this report, we review a sample of 40 detailed transmission studies that have included wind power. These studies cover a broad geographic area, and were completed from 2001-2008. Our primary goal in reviewing these studies is to develop a better understanding of the transmission costs needed to access growing quantities of wind generation. A secondary goal is to gain a better appreciation of the differences in transmission planning approaches in order to identify those methodologies that seem most able to estimate the incremental transmission costs associated with wind development. Finally, we hope that the resulting dataset and discussion might be used to inform the assumptions, methods, and results of higher-level assessment models that are sometimes used to estimate the cost of wind deployment (e.g. NEMS

  4. Improved Performance of Connected Foundations for Resilient Energy Transmission Infrastructure in Soft Soils

    Directory of Open Access Journals (Sweden)

    Doohyun Kyung

    2015-12-01

    Full Text Available The connected foundation is an effective structural type of foundation that can improve the sustainability of electrical transmission towers in soft soils to serve as a resilient energy supply system. In this study, the performance of electrical transmission towers reinforced with connected beams was investigated using a series of field load tests. Model transmission tower structures were manufactured and adopted into the tests. Based on the load capacity mobilization and failure mechanism, a criterion to define the load carrying capacity for connected foundation was proposed. It was found that the performance of connected foundation varies with the mechanical property of connection beam. The load capacity and differential settlement increased and decreased, respectively, with increasing connection beam stiffness. Such effect of connection beam was more pronounced as the height of load application point or tower height (zh increases. Based on the load test results, a design model was proposed that can be used to evaluate the sustainable performance and load carrying capacity of connected foundations. Field load tests with prototype transmission tower structure models were conducted to check and confirm the performance of connected foundation and the proposed design method.

  5. Available transmission capacity assessment

    Directory of Open Access Journals (Sweden)

    Škokljev Ivan

    2012-01-01

    Full Text Available Effective power system operation requires the analysis of vast amounts of information. Power market activities expose power transmission networks to high-level power transactions that threaten normal, secure operation of the power system. When there are service requests for a specific sink/source pair in a transmission system, the transmission system operator (TSO must allocate the available transfer capacity (ATC. It is common that ATC has a single numerical value. Additionally, the ATC must be calculated for the base case configuration of the system, while generation dispatch and topology remain unchanged during the calculation. Posting ATC on the internet should benefit prospective users by aiding them in formulating their requests. However, a single numerical value of ATC offers little for prospect for analysis, planning, what-if combinations, etc. A symbolic approach to the power flow problem (DC power flow and ATC offers a numerical computation at the very end, whilst the calculation beforehand is performed by using symbols for the general topology of the electrical network. Qualitative analysis of the ATC using only qualitative values, such as increase, decrease or no change, offers some new insights into ATC evaluation, multiple transactions evaluation, value of counter-flows and their impact etc. Symbolic analysis in this paper is performed after the execution of the linear, symbolic DC power flow. As control variables, the mathematical model comprises linear security constraints, ATC, PTDFs and transactions. The aim is to perform an ATC sensitivity study on a five nodes/seven lines transmission network, used for zonal market activities tests. A relatively complicated environment with twenty possible bilateral transactions is observed.

  6. NB Power Transmission system

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, J. [NB Power Transmission, Fredericton, NB (Canada)

    2006-07-01

    The NB Power Transmission System operates 6700 km of transmission lines having voltages of 69 kV, 138 kV, 230 kV, and 345 kV. The history of lightning protection on this transmission system was presented. Lightning protection with shield wires has been applied selectively on the 69 kV and 138 kV lines and has been applied to all lines in the 230 kV and 345 kV range. Beginning in 2000, line arresters were installed on selected 69 kV and 138 kV lines. It was noted that although overhead shield wires are commonly installed to capture lightning strikes and shield the conductors, problems can occur if the electrical flashover of insulators result in a line to ground fault. Good grounding is needed to ensure that lightning enters the ground from the tower. The new approach is to install line arresters on structures without overhead shield wires. Line arresters are surge arresters applied in parallel with the insulator string. This new line arrester technology was tested by installing nearly 1200 arresters in the Saint John area. This paper described the reasons for choosing line arresters over shield wires and presented the methods of installation. The problems and failure rates of the installed line arresters were presented along with solutions, including solutions to protect lines against lightning in areas with heavy icing. Recommendations for future research into the use, application and development of line arresters were also presented. tabs., figs.

  7. Load Balancing Scientific Applications

    Energy Technology Data Exchange (ETDEWEB)

    Pearce, Olga Tkachyshyn [Texas A & M Univ., College Station, TX (United States)

    2014-12-01

    The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one at the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.

  8. Power Improvement of Transmission Line Using High Voltage Direct Current (Hvdc Transmission System

    Directory of Open Access Journals (Sweden)

    Lasisi, H

    2016-08-01

    Full Text Available The use of long EHV (Extremely High Voltage ac lines for the transmission of electrical energy increases the line reactance and susceptance which limits the thermal loadings on the line in order to keep sufficient margin against transient instability. With the scheme proposed in this paper, it is possible to load the lines very close to their limit with zero reactance and susceptance. The conductors are allowed to carry usual ac along with dc superimposed on it. The added dc power flow does not cause any transient instability. The scheme comprises a twelve-pulse bridge rectifier, dc-links, pulse width modulated (PSW-voltage sourced inverter (VSI and converter transformers. The master current controller is used to implement the scheme which senses ac current and regulates the dc current orders for converters online such that conductor current never exceeds its thermal limit. This paper gives the feasibility of converting a double circuit ac line into composite ac–dc power transmission line given the advantage of stability improvement, damping oscillations, voltage stabilization and reactive power compensation for ac weak buses. Simulation and experimental studies using MATLAB (Matrix Laboratory are carried out for the coordinated control as well as independent control of ac and dc power transmissions.

  9. Cultural transmission of civic attitudes

    OpenAIRE

    Miles-Touya, Daniel; Rossi, Máximo

    2016-01-01

    In this empirical paper we attempt to measure the separate influence on civic engagement of educational attainment and cultural transmission of civic attitudes. Unlike most of the previous empirical works on this issue, we are able to approximate the cultural transmission of civic attitudes. We observe that civic returns to education are overstated when the transmission of civic attitudes is ignored. Moreover, the transmission of civic attitudes significantly enhances civic involvement and re...

  10. Transmission eigenvalues for elliptic operators

    CERN Document Server

    Hitrik, Michael; Ola, Petri; Päivärinta, Lassi

    2010-01-01

    A reduction of the transmission eigenvalue problem for multiplicative sign-definite perturbations of elliptic operators with constant coefficients to an eigenvalue problem for a non-selfadjoint compact operator is given. Sufficient conditions for the existence of transmission eigenvalues and completeness of generalized eigenstates for the transmission eigenvalue problem are derived. In the trace class case, the generic existence of transmission eigenvalues is established.

  11. Optimizing Transmission Line Matching Circuits

    OpenAIRE

    Novak, S.

    1996-01-01

    When designing transmission line matching circuits, there exist often overlooked, additional, not much used, degree of choice in the selection of the transmission line impedance. In this work are presented results of CAD analysis for the two element transmission line matching networks, demonstrating that selecting matching circuits transmission lines with higher impedance, than usually used 50 or 75 ohms, can in most cases substantially decrease the physical dimension of the final matching ci...

  12. Predicting the Response of Electricity Load to Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Patrick [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Colman, Jesse [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kalendra, Eric [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-07-28

    Our purpose is to develop a methodology to quantify the impact of climate change on electric loads in the United States. We perform simple linear regression, assisted by geospatial smoothing, on paired temperature and load time-series to estimate the heating- and coolinginduced sensitivity to temperature across 300 transmission zones and 16 seasonal and diurnal time periods. The estimated load sensitivities can be coupled with climate scenarios to quantify the potential impact of climate change on load, with a primary application being long-term electricity scenarios. The method allows regional and seasonal differences in climate and load response to be reflected in the electricity scenarios. While the immediate product of this analysis was designed to mesh with the spatial and temporal resolution of a specific electricity model to enable climate change scenarios and analysis with that model, we also propose that the process could be applied for other models and purposes.

  13. Lumbriculus variegatus loading study

    Data.gov (United States)

    U.S. Environmental Protection Agency — Results from sediment bioaccumulation tests with Lumbriculus variegatus with evaluating the effects of organism loading density. This dataset is associated with the...

  14. Carbohydrate-Loading Diet

    Science.gov (United States)

    ... Grape juice (12 ounces) 55 225 Lunch Milk, chocolate, reduced fat (12 ounces) 45 285 4 slices ... of carb-loading for sports performance. Academy of Nutrition and Dietetics. http://www.eatright.org/resource/fitness/ ...

  15. LOADING SIMULATION PROGRAM C

    Data.gov (United States)

    U.S. Environmental Protection Agency — LSPC is the Loading Simulation Program in C++, a watershed modeling system that includes streamlined Hydrologic Simulation Program Fortran (HSPF) algorithms for...

  16. Cognitive load theory

    NARCIS (Netherlands)

    Kirschner, Paul A.; Kirschner, Femke; Paas, Fred

    2010-01-01

    Kirschner, P. A., Kirschner, F. C., & Paas, F. (2009). Cognitive load theory. In E. M. Anderman & L. H. Anderman (Eds.). Psychology of classroom learning: An encyclopedia, Volume 1, a-j (pp. 205-209). Detroit, MI: Macmillan Reference.

  17. Static Loads Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides the capability to perform large-scale structural loads testing on spacecraft and other structures. Results from these tests can be used to verify...

  18. Plug Load Data

    Data.gov (United States)

    National Aeronautics and Space Administration — We provide MATLAB binary files (.mat) and comma separated values files of data collected from a pilot study of a plug load management system that allows for the...

  19. Jerky loads on surface-hardened gears

    Science.gov (United States)

    Rettig, H.; Wirth, X.

    1978-01-01

    Damage occurs again and again in practice in the form of transmissions with surface hardened gears which break after a very long operating time (explained by seldom occurring jerky loads). Gear drives are frequently exposed to jerky stresses which are greater than their fatigue limit. These stresses are considered in gear calculations, first, by shock factors when the transmission is to be designed as high endurance with regard to overloads and, second, in the form of operating ratios when the design is to be time enduring with regard to overloads. The size of the operating ratio depends not only on torque characteristics, drive and processing machine, but also on the material and heat treatment.

  20. Bottlenecks reduction using superconductors in high voltage transmission lines

    Directory of Open Access Journals (Sweden)

    Daloub Labib

    2016-01-01

    Full Text Available Energy flow bottlenecks in high voltage transmission lines known as congestions are one of the challenges facing power utilities in fast developing countries. Bottlenecks occur in selected power lines when transmission systems are operated at or beyond their transfer limits. In these cases, congestions result in preventing new power supply contracts, infeasibility in existing contracts, price spike and market power abuse. The “Superconductor Technology” in electric power transmission cables has been used as a solution to solve the problem of bottlenecks in energy transmission at high voltage underground cables and overhead lines. The increase in demand on power generation and transmission happening due to fast development and linked to the intensive usage of transmission network in certain points, which in turn, lead to often frequent congestion in getting the required power across to where it is needed. In this paper, a bottleneck in high voltage double overhead transmission line with Aluminum Conductor Steel Reinforced was modeled using conductor parameters and replaced by Gap-Type Superconductor to assess the benefit of upgrading to higher temperature superconductor and obtain higher current carrying capacity. This proved to reduce the high loading of traditional aluminum conductors and allow more power transfer over the line using superconductor within the same existing right-of-way, steel towers, insulators and fittings, thus reducing the upgrade cost of building new lines.

  1. Strength Check Analysis for Gear Shaft of Automobile Transmission

    Directory of Open Access Journals (Sweden)

    Yongxiang Li

    2013-09-01

    Full Text Available As the main drive components of the automobile transmission, the performance of gear shaft plays an important role on transmission performance. Aiming at the existing problems of the traditional strength check method of gear shaft, the objective of this study is to take a five-speed transmission as an example, to accomplish the strength analysis of gear shaft of the automobile transmission based on the MASTA software. Furthermore, the simulation modeling of the transmission is built completely to simulate the actual load conditions and complete the process of analysis for the gear shaft. Analytical results show that all gear shafts can fully meet the strength requirements, in addition to the input shaft which has any further improvements. Hence, it is indicated that a new design concept is put forward, that is, using specialized software MASTA for transmission modeling and simulation analysis can heavily improve the design level of the gear shaft, provide the theoretic basis to analyze the dynamic characteristics of gear shaft as well. Finally, it can provide references for the development and application of gear shaft of the automobile transmission.

  2. Spur, helical, and spiral bevel transmission life modeling

    Science.gov (United States)

    Savage, Michael; Rubadeux, Kelly L.; Coe, Harold H.; Coy, John J.

    1994-04-01

    A computer program, TLIFE, which estimates the life, dynamic capacity, and reliability of aircraft transmissions, is presented. The program enables comparisons of transmission service life at the design stage for optimization. A variety of transmissions may be analyzed including: spur, helical, and spiral bevel reductions as well as series combinations of these reductions. The basic spur and helical reductions include: single mesh, compound, and parallel path plus revert star and planetary gear trains. A variety of straddle and overhung bearing configurations on the gear shafts are possible as is the use of a ring gear for the output. The spiral bevel reductions include single and dual input drives with arbitrary shaft angles. The program is written in FORTRAN 77 and has been executed both in the personal computer DOS environment and on UNIX workstations. The analysis may be performed in either the SI metric or the English inch system of units. The reliability and life analysis is based on the two-parameter Weibull distribution lives of the component gears and bearings. The program output file describes the overall transmission and each constituent transmission, its components, and their locations, capacities, and loads. Primary output is the dynamic capacity and 90-percent reliability and mean lives of the unit transmissions and the overall system which can be used to estimate service overhaul frequency requirements. Two examples are presented to illustrate the information available for single element and series transmissions.

  3. Impacts of Demand-Side Resources on Electric Transmission Planning

    Energy Technology Data Exchange (ETDEWEB)

    Hadley, Stanton W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sanstad, Alan H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-01

    Will demand resources such as energy efficiency (EE), demand response (DR), and distributed generation (DG) have an impact on electricity transmission requirements? Five drivers for transmission expansion are discussed: interconnection, reliability, economics, replacement, and policy. With that background, we review the results of a set of transmission studies that were conducted between 2010 and 2013 by electricity regulators, industry representatives, and other stakeholders in the three physical interconnections within the United States. These broad-based studies were funded by the US Department of Energy and included scenarios of reduced load growth due to EE, DR, and DG. While the studies were independent and used different modeling tools and interconnect-specific assumptions, all provided valuable results and insights. However, some caveats exist. Demand resources were evaluated in conjunction with other factors, and limitations on transmission additions between scenarios made understanding the role of demand resources difficult. One study, the western study, included analyses over both 10- and 20-year planning horizons; the 10-year analysis did not show near-term reductions in transmission, but the 20-year indicated fewer transmission additions, yielding a 36percent capital cost reduction. In the eastern study the reductions in demand largely led to reductions in local generation capacity and an increased opportunity for low-cost and renewable generation to export to other regions. The Texas study evaluated generation changes due to demand, and is in the process of examining demand resource impacts on transmission.

  4. Conventional transmission electron microscopy.

    Science.gov (United States)

    Winey, Mark; Meehl, Janet B; O'Toole, Eileen T; Giddings, Thomas H

    2014-02-01

    Researchers have used transmission electron microscopy (TEM) to make contributions to cell biology for well over 50 years, and TEM continues to be an important technology in our field. We briefly present for the neophyte the components of a TEM-based study, beginning with sample preparation through imaging of the samples. We point out the limitations of TEM and issues to be considered during experimental design. Advanced electron microscopy techniques are listed as well. Finally, we point potential new users of TEM to resources to help launch their project.

  5. Dynamically prioritized progressive transmission

    Science.gov (United States)

    Blanford, Ronald

    1992-04-01

    Retrieval of image data from a centralized database may be subject to bandwidth limitations, whether due to a low-bandwidth communications link or to contention from simultaneous accesses over a high-bandwidth link. Progressive transmission can alleviate this problem by encoding image data so that any prefix of the data stream approximates the complete image at a coarse level of resolution. The longer the prefix, the finer the resolution. In many cases, as little at 1 percent of the image data may be sufficient to decide whether to discard the image, to permit the retrieval to continue, or to restrict retrieval to a subsection of the image. Our approach treats resolution not as a fixed attribute of the image, but rather as a resource which may be allocated to portions of the image at the direction of a user-specified priority function. The default priority function minimizes error by allocating more resolution to regions of high variance. The user may also point to regions of interest requesting priority transmission. More advanced target recognition strategies may be incorporated at the user's discretion. Multispectral imagery is supported. The user engineering implications are profounded. There is immediate response to a query that might otherwise take minutes to complete. The data is transmitted in small increments so that no single user dominates the communications bandwidth. The user-directed improvement means that bandwidth is focused on interesting information. The user may continue working with the first coarse approximations while further image data is still arriving. The algorithm has been implemented in C on Sun, Silicon Graphics, and NeXT workstations, and in Lisp on a Symbolics. Transmission speeds reach as high as 60,000 baud using a Sparc or 68040 processor when storing data to memory; somewhat less if also updating a graphical display. The memory requirements are roughly five bytes per image pixel. Both computational and memory costs may be reduced

  6. Research and Transmission

    Directory of Open Access Journals (Sweden)

    Denise Pumain

    2001-01-01

    Full Text Available The present situation provides a challenge for us to reconsider the necessary link between science and pedagogy, between research and the transmission of knowledge. The Ministry of National education has just inaugurated a broad consultation of teachers on every level with a view to modernising and giving coherence to the programs of secondary education. Armand Frémont will head the group of experts responsible for history and geography. Is this a coincidence? The changeover in the jury for t...

  7. Quantum Contact Transmission

    Institute of Scientific and Technical Information of China (English)

    崔迪

    2015-01-01

    Abstract:Quantum transmission is based on quantum entanglement, which is a kind of the phenomenon of quantum mechanics. Quantum object refers to two or more between the localized, the classic strong correlation. When two object quantum entanglement in the quantum state is not independent, but related, and the correlation distance, a pair of electronic of entanglement state, no matter how far apart, they spin direction will remain an up and a down. If one of the electronic spin direction is changed, another of the electron spin direction wil follow to change immediately.

  8. Multipath Load Balancing Routing for Internet of Things

    Directory of Open Access Journals (Sweden)

    Chinyang Henry Tseng

    2016-01-01

    Full Text Available In the next-generation technology, Internet of Things (IoT, billions of smart objects will communicate with one another to make human lives more convenient. IoT is based on wireless sensor network (WSN, and Zigbee is one of the most popular WSN protocols. A mature IoT environment involves heavy WSN data transmission causing bottleneck problems. However, Zigbee’s AODV routing stack does not have load balance mechanism to handle bursty traffic. Therefore, we develop Multipath Load Balancing (MLB Routing to substitute Zigbee’s AODV routing. Our proposed MLB consists of two main designs: LAYER_DESIGN and LOAD_BALANCE. LAYER_DESIGN assigns nodes into different layers based on node distance to IoT gateway. Nodes can have multiple next-hops delivering IoT data. All neighboring layer nodes exchange flow information containing current load, used by LOAD_BALANCE to estimate future load of next-hops. With MLB, nodes can choose the neighbors with the least load as the next-hops and thus can achieve load balance and avoid bottlenecks. Compared with Zigbee’s AODV and multipath version AODV (AOMDV, experiment results demonstrate that MLB achieves better load balance, lower packet loss rate, and better routing connectivity ratio in both grid and random uniform topologies. MLB provides a more convincing routing solution for IoT applications.

  9. [Oral transmission of Chagas' disease].

    Science.gov (United States)

    Toso M, Alberto; Vial U, Felipe; Galanti, Norbel

    2011-02-01

    The traditional transmission pathways of Chagas' disease are vectorial, transfusional, transplacental and organ transplantation. However, oral transmission is gaining importance. The first evidence of oral transmission was reported in Brazil in 1965. Nowadays the oral route is the transmission mode in 50% of cases in the Amazon river zone. Oral infection is produced by the ingestion of infected triatomine bugs or their feces, undercooked meat from infested host animals and food contaminated with urine or anal secretion of infected marsupials. Therefore travelers to those zones should be advised about care to be taken with ingested food. In Chile, this new mode of transmission should be considered in public health policies.

  10. Transmission Properties of Fiber Probes

    Institute of Scientific and Technical Information of China (English)

    XUE Chun-rong; ZHU Sheng-xiang; XIAO Zhi-gang

    2004-01-01

    Transmission properties of tapered fiber including right cone fiber and bend optical fiber are discussed. The transmission efficiency of the tapered fiber is measured. The curve of transmission efficiency versus taper cone angle is given. By the scalar wave equation and Gaussian approximation, transmission properties of the two kinds of tapered fibers are analyzed, the power losses caused by taper cone angle and by the bending are also calculated. From the experiments and theoretical analysis, it could come to a conclusion that the wider the taper cone angle is, the higher the transmission efficiency will be.

  11. Dynamics of a split torque helicopter transmission

    Science.gov (United States)

    Krantz, Timothy L.

    1994-06-01

    Split torque designs, proposed as alternatives to traditional planetary designs for helicopter main rotor transmissions, can save weight and be more reliable than traditional designs. This report presents the results of an analytical study of the system dynamics and performance of a split torque gearbox that uses a balance beam mechanism for load sharing. The Lagrange method was applied to develop a system of equations of motion. The mathematical model includes time-varying gear mesh stiffness, friction, and manufacturing errors. Cornell's method for calculating the stiffness of spur gear teeth was extended and applied to helical gears. The phenomenon of sidebands spaced at shaft frequencies about gear mesh fundamental frequencies was simulated by modeling total composite gear errors as sinusoid functions. Although the gearbox has symmetric geometry, the loads and motions of the two power paths differ. Friction must be considered to properly evaluate the balance beam mechanism. For the design studied, the balance beam is not an effective device for load sharing unless the coefficient of friction is less than 0.003. The complete system stiffness as represented by the stiffness matrix used in this analysis must be considered to precisely determine the optimal tooth indexing position.

  12. [Pregnancy: a model of prevention of HIV transmission].

    Science.gov (United States)

    Mandelbrot, Laurent

    2014-01-01

    Antiretroviral drugs are primarily used to treat people living with HIV but can also reduce the risk of transmission. The first application of this prophylactic approach was in the prevention of mother-to-child transmission, which comprises three components: 1) antiretroviral therapy during pregnancy to reduce maternal viral load, 2) pre-exposure prophylactic treatment of the fetus in utero and intrapartum, and 3) postexposure neonatal treatment. This has resulted in a sharp reduction in mother-to-child transmission, to well below 1 % in France today. "Treatment as prevention" (TASP) is now widely recommended to prevent sexual transmission to partners of people living with HIV articularly when a couple wishes to have children. Achieving and sustaining undetectable viral load is an important means of reducing the risk of sexual transmission in serodiscordant couples and also of controlling the pandemic worldwide. The other uses of antiretroviral drugs to protect HIV-negative people at risk include post-exposure prophylaxis (PEP) and pre-exposure prophylaxis (PrEP). Prevention has both individual and collective dimensions and involves several components, including behavioral changes, serological testing, and use of antiretrovirals.

  13. Load scheduling for decentralized CHP plants

    DEFF Research Database (Denmark)

    Nielsen, Henrik Aalborg, orlov 31.07.2008; Madsen, Henrik; Nielsen, Torben Skov

    This report considers load scheduling for decentralized combined heat and power plants where the revenue from selling power to the transmission company and the fuel cost may be time-varying. These plants produce both heat and power with a fixed ratio between these outputs. A heat storage facility...... is used to be able to deviate from this restriction. The load scheduling must be performed with only approximate knowledge about the future. At present in Denmark this uncertainty is only associated with the heat demand, but in the future revenues of produced energy and the fuel costs might also...... be uncertain and dependent on time. It is suggested to use a combination of background knowledge of the operator and computer tools to solve the scheduling problem. More specificly it is suggested that the plant is equipped with (i) an automatic on-line system for forecasting the heat demand, (ii...

  14. Estimation of dynamic rotor loads for the rotor systems research aircraft: Methodology development and validation

    Science.gov (United States)

    Duval, R. W.; Bahrami, M.

    1985-01-01

    The Rotor Systems Research Aircraft uses load cells to isolate the rotor/transmission systm from the fuselage. A mathematical model relating applied rotor loads and inertial loads of the rotor/transmission system to the load cell response is required to allow the load cells to be used to estimate rotor loads from flight data. Such a model is derived analytically by applying a force and moment balance to the isolated rotor/transmission system. The model is tested by comparing its estimated values of applied rotor loads with measured values obtained from a ground based shake test. Discrepancies in the comparison are used to isolate sources of unmodeled external loads. Once the structure of the mathematical model has been validated by comparison with experimental data, the parameters must be identified. Since the parameters may vary with flight condition it is desirable to identify the parameters directly from the flight data. A Maximum Likelihood identification algorithm is derived for this purpose and tested using a computer simulation of load cell data. The identification is found to converge within 10 samples. The rapid convergence facilitates tracking of time varying parameters of the load cell model in flight.

  15. Gearbox design for uncertain load requirements using active robust optimization

    Science.gov (United States)

    Salomon, Shaul; Avigad, Gideon; Purshouse, Robin C.; Fleming, Peter J.

    2016-04-01

    Design and optimization of gear transmissions have been intensively studied, but surprisingly the robustness of the resulting optimal design to uncertain loads has never been considered. Active Robust (AR) optimization is a methodology to design products that attain robustness to uncertain or changing environmental conditions through adaptation. In this study the AR methodology is utilized to optimize the number of transmissions, as well as their gearing ratios, for an uncertain load demand. The problem is formulated as a bi-objective optimization problem where the objectives are to satisfy the load demand in the most energy efficient manner and to minimize production cost. The results show that this approach can find a set of robust designs, revealing a trade-off between energy efficiency and production cost. This can serve as a useful decision-making tool for the gearbox design process, as well as for other applications.

  16. Broadband transmission EPR spectroscopy.

    Directory of Open Access Journals (Sweden)

    Wilfred R Hagen

    Full Text Available EPR spectroscopy employs a resonator operating at a single microwave frequency and phase-sensitive detection using modulation of the magnetic field. The X-band spectrometer is the general standard with a frequency in the 9-10 GHz range. Most (biomolecular EPR spectra are determined by a combination of the frequency-dependent electronic Zeeman interaction and a number of frequency-independent interactions, notably, electron spin - nuclear spin interactions and electron spin - electron spin interactions, and unambiguous analysis requires data collection at different frequencies. Extant and long-standing practice is to use a different spectrometer for each frequency. We explore the alternative of replacing the narrow-band source plus single-mode resonator with a continuously tunable microwave source plus a non-resonant coaxial transmission cell in an unmodulated external field. Our source is an arbitrary wave digital signal generator producing an amplitude-modulated sinusoidal microwave in combination with a broadband amplifier for 0.8-2.7 GHz. Theory is developed for coaxial transmission with EPR detection as a function of cell dimensions and materials. We explore examples of a doublet system, a high-spin system, and an integer-spin system. Long, straigth, helical, and helico-toroidal cells are developed and tested with dilute aqueous solutions of spin label hydroxy-tempo. A detection limit of circa 5 µM HO-tempo in water at 800 MHz is obtained for the present setup, and possibilities for future improvement are discussed.

  17. Elastic Dynamic Stability of Big-Span Power Transmission Tower Subjected to Seismic Excitations

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hang; LI Li; FANG Qin-han; YE Kun

    2009-01-01

    By combining the time-history response analysis and the eigenvalue buckling analysis,this paper developed a computational procedure to study the elastic dynamic stability of a transmission tower by APDL language in ANSYS.The influences of different input directions of seismic excitations and damping ratio on the elastic dynamic stability of tower were discussed.The following conclusions were obtained:(1) Longitudinal direction of the transmission lines is the worst input direction of seismic excitation for the transmission tower.(2) Dead load has no significant effect on the critical load and the occurrence time of buckling.(3) Vertical input of seismic excitations has no great effect on the dynamic stability of the transmission tower.(4) Damping effect has an influence on the dynamic stability of the transmission tower; however,the inherent characteristics of dynamic buckling is not changed.

  18. The integration of renewable energy sources into electric power transmission systems

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, P.R.; Dykas, W.P.; Kirby, B.J.; Purucker, S.L. [Oak Ridge National Lab., TN (United States); Lawler, J.S. [Univ. of Tennessee, Knoxville, TN (United States)

    1995-07-01

    Renewable energy technologies such as photovoltaics, solar thermal power plants, and wind turbines are nonconventional, environmentally attractive sources of energy that can be considered for electric power generation. Many of the areas with abundant renewable energy resources (very sunny or windy areas) are far removed from major load centers. Although electrical power can be transmitted over long distances of many hundreds of miles through high-voltage transmission lines, power transmission systems often operate near their limits with little excess capacity for new generation sources. This study assesses the available capacity of transmission systems in designated abundant renewable energy resource regions and identifies the requirements for high-capacity plant integration in selected cases. In general, about 50 MW of power from renewable sources can be integrated into existing transmission systems to supply local loads without transmission upgrades beyond the construction of a substation to connect to the grid. Except in the Southwest, significant investment to strengthen transmission systems will be required to support the development of high-capacity renewable sources of 1000 MW or greater in areas remote from major load centers. Cost estimates for new transmission facilities to integrate and dispatch some of these high-capacity renewable sources ranged from several million dollars to approximately one billion dollars, with the latter figure an increase in total investment of 35%, assuming that the renewable source is the only user of the transmission facility.

  19. Integration of MHD load models with circuit representations the Z generator.

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, Christopher A.; Ampleford, David J.; Jones, Brent Manley; McBride, Ryan D.; Bailey, James E.; Jones, Michael C.; Gomez, Matthew Robert.; Cuneo, Michael Edward; Nakhleh, Charles; Stygar, William A.; Savage, Mark Edward; Wagoner, Timothy C.; Moore, James K.

    2013-03-01

    MHD models of imploding loads fielded on the Z accelerator are typically driven by reduced or simplified circuit representations of the generator. The performance of many of the imploding loads is critically dependent on the current and power delivered to them, so may be strongly influenced by the generators response to their implosion. Current losses diagnosed in the transmission lines approaching the load are further known to limit the energy delivery, while exhibiting some load dependence. Through comparing the convolute performance of a wide variety of short pulse Z loads we parameterize a convolute loss resistance applicable between different experiments. We incorporate this, and other current loss terms into a transmission line representation of the Z vacuum section. We then apply this model to study the current delivery to a wide variety of wire array and MagLif style liner loads.

  20. Permeability Evolution in Natural Fractures Subject to Cyclic Loading and Gouge Formation

    Science.gov (United States)

    Vogler, Daniel; Amann, Florian; Bayer, Peter; Elsworth, Derek

    2016-09-01

    Increasing fracture aperture by lowering effective normal stress and by inducing dilatant shearing and thermo-elastic effects is essential for transmissivity increase in enhanced geothermal systems. This study investigates transmissivity evolution for fluid flow through natural fractures in granodiorite at the laboratory scale. Processes that influence transmissivity are changing normal loads, surface deformation, the formation of gouge and fracture offset. Normal loads were varied in cycles between 1 and 68 MPa and cause transmissivity changes of up to three orders of magnitude. Similarly, small offsets of fracture surfaces of the order of millimeters induced changes in transmissivity of up to three orders of magnitude. During normal load cycling, the fractures experienced significant surface deformation, which did not lead to increased matedness for most experiments, especially for offset fractures. The resulting gouge material production may have caused clogging of the main fluid flow channels with progressing loading cycles, resulting in reductions of transmissivity by up to one order of magnitude. During one load cycle, from low to high normal loads, the majority of tests show hysteretic behavior of the transmissivity. This effect is stronger for early load cycles, most likely when surface deformation occurs, and becomes less pronounced in later cycles when asperities with low asperity strength failed. The influence of repeated load cycling on surface deformation is investigated by scanning the specimen surfaces before and after testing. This allows one to study asperity height distribution and surface deformation by evaluating the changes of the standard deviation of the height, distribution of asperities and matedness of the fractures. Surface roughness, as expressed by the standard deviation of the asperity height distribution, increased during testing. Specimen surfaces that were tested in a mated configuration were better mated after testing, than

  1. Millikelvin thermal and electrical performance of lossy transmission line filters

    Energy Technology Data Exchange (ETDEWEB)

    Slichter, Daniel; Naaman, Ofer; Siddiqi, Irfan

    2009-03-11

    We report on the scattering parameters and Johnson noise emission of low-pass stripline filters employing a magnetically loaded silicone dielectric down to 25 mK. The transmission characteristic of a device with f-3dB=1.3 GHz remains essentially unchanged upon cooling. Another device with f-edB=0.4 GHz, measured in its stopband, exhibits a steady state noise power emission consistent with a temperature difference of a few mK relative to a well-anchored cryogenic microwave attenuator at temperatures down to 25 mK, thus presenting a matched thermal load.

  2. Great Plains Wind Energy Transmission Development Project

    Energy Technology Data Exchange (ETDEWEB)

    Brad G. Stevens, P.E.; Troy K. Simonsen; Kerryanne M. Leroux

    2012-06-09

    In fiscal year 2005, the Energy & Environmental Research Center (EERC) received funding from the U.S. Department of Energy (DOE) to undertake a broad array of tasks to either directly or indirectly address the barriers that faced much of the Great Plains states and their efforts to produce and transmit wind energy at the time. This program, entitled Great Plains Wind Energy Transmission Development Project, was focused on the central goal of stimulating wind energy development through expansion of new transmission capacity or development of new wind energy capacity through alternative market development. The original task structure was as follows: Task 1 - Regional Renewable Credit Tracking System (later rescoped to Small Wind Turbine Training Center); Task 2 - Multistate Transmission Collaborative; Task 3 - Wind Energy Forecasting System; and Task 4 - Analysis of the Long-Term Role of Hydrogen in the Region. As carried out, Task 1 involved the creation of the Small Wind Turbine Training Center (SWTTC). The SWTTC, located Grand Forks, North Dakota, consists of a single wind turbine, the Endurance S-250, on a 105-foot tilt-up guyed tower. The S-250 is connected to the electrical grid on the 'load side' of the electric meter, and the power produced by the wind turbine is consumed locally on the property. Establishment of the SWTTC will allow EERC personnel to provide educational opportunities to a wide range of participants, including grade school through college-level students and the general public. In addition, the facility will allow the EERC to provide technical training workshops related to the installation, operation, and maintenance of small wind turbines. In addition, under Task 1, the EERC hosted two small wind turbine workshops on May 18, 2010, and March 8, 2011, at the EERC in Grand Forks, North Dakota. Task 2 involved the EERC cosponsoring and aiding in the planning of three transmission workshops in the midwest and western regions. Under Task

  3. TE(01) High Power Disk Loaded Guide Load

    CERN Document Server

    Farkas, Zoltan D

    2005-01-01

    A method to design a matching section from a smooth guide to a disk loaded guide, using a variation of broadband matching* is described. Using this method, we show how to design high power loads, filters and attenuators. The load consists of a disk loaded coaxial guide, operating in the T01

  4. E-2C Loads Calibration in DFRC Flight Loads Lab

    Science.gov (United States)

    Schuster, Lawrence S.

    2008-01-01

    Objectives: a) Safely and efficiently perform structural load tests on NAVAIR E-2C aircraft to calibrate strain gage instrumentation installed by NAVAIR; b) Collect load test data and derive loads equations for use in NAVAIR flight tests; and c) Assist flight test team with use of loads equations measurements at PAX River.

  5. Biophysical characterization of gold nanoparticles-loaded liposomes.

    Science.gov (United States)

    Mady, Mohsen Mahmoud; Fathy, Mohamed Mahmoud; Youssef, Tareq; Khalil, Wafaa Mohamed

    2012-10-01

    Gold nanoparticles were prepared and loaded into the bilayer of dipalmitoylphosphatidylcholine (DPPC) liposomes, named as gold-loaded liposomes. Biophysical characterization of gold-loaded liposomes was studied by transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy as well as turbidity and rheological measurements. FTIR measurements showed that gold nanoparticles made significant changes in the frequency of the CH(2) stretching bands, revealing that gold nanoparticles increased the number of gauche conformers and create a conformational change within the acyl chains of phospholipids. The transmission electron micrographs (TEM) revealed that gold nanoparticles were loaded in the liposomal bilayer. The zeta potential of DPPC liposomes had a more negative value after incorporating of Au NPs into liposomal membranes. Turbidity studies revealed that the loading of gold nanoparticles into DPPC liposomes results in shifting the temperature of the main phase transition to a lower value. The membrane fluidity of DPPC bilayer was increased by loading the gold nanoparticles as shown from rheological measurements. Knowledge gained in this study may open the door to pursuing liposomes as a viable strategy for Au NPs delivery in many diagnostic and therapeutic applications.

  6. Comparison of Transmission Error Predictions with Noise Measurements for Several Spur and Helical Gears

    Science.gov (United States)

    Houser, Donald R.; Oswald, Fred B.; Valco, Mark J.; Drago, Raymond J.; Lenski, Joseph W., Jr.

    1994-01-01

    Measured sound power data from eight different spur, single and double helical gear designs are compared with predictions of transmission error by the Load Distribution Program. The sound power data was taken from the recent Army-funded Advanced Rotorcraft Transmission project. Tests were conducted in the NASA gear noise rig. Results of both test data and transmission error predictions are made for each harmonic of mesh frequency at several operating conditions. In general, the transmission error predictions compare favorably with the measured noise levels.

  7. Comparison of transmission error predictions with noise measurements for several spur and helical gears

    Science.gov (United States)

    Houser, Donald R.; Oswald, Fred B.; Valco, Mark J.; Drago, Raymond J.; Lenski, Joseph W., Jr.

    1994-06-01

    Measured sound power data from eight different spur, single and double helical gear designs are compared with predictions of transmission error by the Load Distribution Program. The sound power data was taken from the recent Army-funded Advanced Rotorcraft Transmission project. Tests were conducted in the NASA gear noise rig. Results of both test data and transmission error predictions are made for each harmonic of mesh frequency at several operating conditions. In general, the transmission error predictions compare favorably with the measured noise levels.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Troubadours & Troublemakers: Stirring the Network in Transmission & Anti-Transmission

    Directory of Open Access Journals (Sweden)

    Jeff T. Johnson

    2017-04-01

    Full Text Available With reference to concepts developed in Trouble Songs: A Musicological Poetics, our objective is to locate trouble (and “trouble” in and around song, while attending to media forms, transmission processes, and embodied figures that carry trouble through song. These figures include trouble singer, troubadour and DJ, where the latter combines the roles of media curator, Mixmaster and MC. An exploration of and through these interrelated figures serves to elaborate a theory of transmission and anti-transmission of trouble. In all cases we are concerned with the technology of trouble, as well as modes and techniques for its transmission.

  10. Fifth Baltic Sea pollution load compilation (PLC-5). An executive summary

    Energy Technology Data Exchange (ETDEWEB)

    Svendsen, L.M.; Staaf, H.; Pyhala, M.; Kotilainen, P.; Bartnicki, J.; Knuuttila, S.; Durkin, M.

    2012-07-01

    This report summarizes and combines the main results of the Fifth Baltic Sea Pollution Load Compilation (HELCOM 2011) which covers waterborne loads to the sea and data on atmospheric loads which are submitted by countries to the co-operative programme for monitoring and evaluation of the long range transmission of air pollutants in Europe (EMEP), which subsequently compiles and reports this information to HELCOM.

  11. Nonlinear transmission sputtering

    Science.gov (United States)

    Bitensky, I. S.; Sigmund, P.

    1996-05-01

    General expressions have been derived for the nonlinear yield of transmission sputtering for an incident polyatomic ion under the assumption that the molecule breaks up on entering the target and that sputter yields are enhanced due to proximity of atomic trajectories. Special attention is given to the case of negligible Coulomb explosion where projectile atoms penetrate independently. For weakly overlapping trajectories, the yield enhancement factor of a polyatomic molecule can be expressed by that of a diatom, amended with a correction for triple correlations if necessary. This expression is in good agreement with recent experimental findings on phenylalanine targets. Pertinent results on multiple scattering of atomic ions are reviewed and applied to independently-moving fragment atoms. The merits of measurements at variable layer thickness in addition to variable projectile energy are mentioned.

  12. Laterally loaded masonry

    DEFF Research Database (Denmark)

    Raun Gottfredsen, F.

    In this thesis results from experiments on mortar joints and masonry as well as methods of calculation of strength and deformation of laterally loaded masonry are presented. The strength and deformation capacity of mortar joints have been determined from experiments involving a constant compressive...... stress and increasing shear. The results show a transition to pure friction as the cohesion is gradually destroyed. An interface model of a mortar joint that can take into account this aspect has been developed. Laterally loaded masonry panels have also been tested and it is found to be characteristic...

  13. Wave Loads on Cylinders

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Frigaard, Peter

    1989-01-01

    Wave loads may be defined as time varying forces on a body resulting from the wave induced flow fields which surrounds the body in whole or in part. Such unsteady fluid forces are the net result of pressure and shear forces integrated over the instantaneous wetted area.......Wave loads may be defined as time varying forces on a body resulting from the wave induced flow fields which surrounds the body in whole or in part. Such unsteady fluid forces are the net result of pressure and shear forces integrated over the instantaneous wetted area....

  14. Empirical Investigations of the Opportunity Limits of Automatic Residential Electric Load Shaping

    Energy Technology Data Exchange (ETDEWEB)

    Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan; Hodge, Bri-Mathias S.; Florita, Anthony R.

    2017-05-11

    Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper and lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.

  15. Empirical Investigations of the Opportunity Limits of Automatic Residential Electric Load Shaping: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan; Hodge, Bri-Mathias S.; Florita, Anthony R.

    2017-04-01

    Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper and lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.

  16. Direct and indirect loading of the Ilizarov external fixator: the effect on the interfragmentary movements and compressive loads.

    Science.gov (United States)

    Gessmann, Jan; Baecker, Hinnerk; Jettkant, Birger; Muhr, Gert; Seybold, Dominik

    2011-04-01

    The amount of weight bearing and the force transmission to the frame have an important influence on the results of treatment with an Ilizarov external fixator. The frame provides beneficial interfragmentary movements and compressive loads at the fracture site through elastic wires. Mobilisation can be achieved by applying a weight-bearing platform at the distal end of the fixator. The effect on the interfragmentary movements and the compressive loads in indirect and direct loading were analysed in this study using a composite tibia bone model. Displacement transducers were attached to measure the interfragmentary movements and to detect relative movements of the bone fragments and movements between the rings. The compressive loads in the osteotomy were measured with loading cells in the defect zone. The weight-bearing platform had a substantial effect on the biomechanical behaviour of the frame. It led to an indirect force transmission through the fixator with respect to the osteotomy, resulting in lower compressive loads, lower interfragmentary movements and higher mechanical stress on the frame.

  17. Technology of optical azimuth transmission

    Science.gov (United States)

    Lu, Honggang; Hu, Chunsheng; Wang, Xingshu; Gao, Yang

    2012-11-01

    It often needs transfer a reference from one place to another place in aerospace and guided missile launching. At first, principles of several typical optical azimuth transmission methods are presented. Several typical methods are introduced, such as Theodolite (including gyro-theodolite) collimation method, Camera series method, Optical apparatus for azimuth method and polarization modulated light transmission method. For these typical azimuth transmission methods, their essential theories are elaborated. Then the devices, the application fields and limitations of these typical methods' are presented. Theodolite (including gyro-theodolite) collimation method is used in the ground assembly of spacecraft. Camera series method and optical apparatus for azimuth method are used in azimuth transmission between different decks of ship. Polarization modulated light transmission method is used in azimuth transmission of rocket and guided missile. At the last, the further developments of these methods are discussed.

  18. International Transmission Under Bretton Woods

    OpenAIRE

    Alan C. Stockman

    1992-01-01

    This paper explores the main channels of international transmission of economic disturbances under the Bretton Woods System and presents evidence on the short-run international transmission of inflation under that system. There appears to have been little short-run international transmission of inflation. Countries with one-percent higher money-growth rates subsequently had one-fourth to one-half percent higher inflation and a (predictably) lower real interest rate. This probably reflects eff...

  19. Load research and load estimation in electricity distribution

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland). Energy Systems

    1996-12-31

    The topics introduced in this thesis are: the Finnish load research project, a simple form customer class load model, analysis of the origins of customers load distribution, a method for the estimation of the confidence interval of customer loads and Distribution Load Estimation (DLE) which utilises both the load models and measurements from distribution networks. The Finnish load research project started in 1983. The project was initially coordinated by the Association of Finnish Electric Utilities and 40 utilities joined the project. Now there are over 1000 customer hourly load recordings in a database. A simple form customer class load model is introduced. The model is designed to be practical for most utility applications and has been used by the Finnish utilities for several years. The only variable of the model is the customers annual energy consumption. The model gives the customers average hourly load and standard deviation for a selected month, day and hour. The statistical distribution of customer loads is studied and a model for customer electric load variation is developed. The model results in a lognormal distribution as an extreme case. Using the `simple form load model`, a method for estimating confidence intervals (confidence limits) of customer hourly load is developed. The two methods selected for final analysis are based on normal and lognormal distribution estimated in a simplified manner. The estimation of several cumulated customer class loads is also analysed. Customer class load estimation which combines the information from load models and distribution network load measurements is developed. This method, called Distribution Load Estimation (DLE), utilises information already available in the utilities databases and is thus easy to apply

  20. WIRELESS POWER TRANSMISSION USING INDUCTIVE RESONANCE COUPLING IN MOBILE CHARGERING

    OpenAIRE

    Valarmathi Krishnan*, N. Suyambu, Vijayaragavan. M, Rajalakshmi. S

    2016-01-01

    The objective of this technical report is to provide electrical energy to remote objects without wires.   Wireless energy transfer also known as wireless energy transmission is the process that takes place in any system where electromagnetic energy is transmitted from a power source to an electrical load, without interconnecting wires. The principle of wireless electricity works on the principle of using coupled resonant objects for the transfer of electricity to objects without the use of an...

  1. Probabilistic Load Flow

    DEFF Research Database (Denmark)

    Chen, Peiyuan; Chen, Zhe; Bak-Jensen, Birgitte

    2008-01-01

    This paper reviews the development of the probabilistic load flow (PLF) techniques. Applications of the PLF techniques in different areas of power system steady-state analysis are also discussed. The purpose of the review is to identify different available PLF techniques and their corresponding...

  2. The interior transmission problem and bounds on transmission eigenvalues

    CERN Document Server

    Hitrik, Michael; Ola, Petri; Päivärinta, Lassi

    2010-01-01

    We study the interior transmission eigenvalue problem for sign-definite multiplicative perturbations of the Laplacian in a bounded domain. We show that all but finitely many complex transmission eigenvalues are confined to a parabolic neighborhood of the positive real axis.

  3. Cytotoxicity of liver targeted drug-loaded alginate nanoparticles

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this study, novel liver targeted doxorubicin (DOX) loaded alginate (ALG) nanoparticles were prepared by CaCl2 crosslinking method. Glycyrrhetinic acid (GA, a liver targeted molecule) modified alginate (GA-ALG) was synthesized in a heterogeneous system, and the structure of GA-ALG and the substitu-tion degree of GA were analyzed by 1H NMR, FT-IR and elemental analysis. The drug release profile under the simulated physiological condition and cytotoxicity experiments of drug-loaded GA-ALG nanoparticles were carried out in vitro. Transmission electron micrographs (TEM) and dynamic light scattering (DLS) analysis showed that drug-loaded GA-ALG nanoparticles have spherical shape structure with the mean hydrodynamic diameter around 214 ± 11 nm. The drug release was shown to last 20 days, and the MTT assay suggested that drug-loaded GA-ALG nanoparticles had a distinct kill-ing effect on 7703 hepatocellular carcinoma cells.

  4. Cytotoxicity of liver targeted drug-loaded aiginate nanoparticles

    Institute of Scientific and Technical Information of China (English)

    ZHANG ChuangNian; WANG Wei; WANG ChunHong; TIAN Qin; HUANG Wei; YUAN Zhi; CHEN XueSi

    2009-01-01

    In this study,novel liver targeted doxorubicin (DOX) loaded alginate (ALG) nanoparticles were prepared by CaCl2 crosslinking method.Glycyrrhetinic acid (GA,a liver targeted molecule) modified alginate (GA-ALG) was synthesized in a heterogeneous system,and the structure of GA-ALG and the substitution degree of GA were analyzed by 1H NMR,FT-IR and elemental analysis.The drug release profile under the simulated physiological condition and cytotoxicity experiments of drug-loaded GA-ALG nanoparticles were carried out in vitro.Transmission electron micrographs (TEM) and dynamic light scattering (DLS) analysis showed that drug-loaded GA-ALG nanoparticles have spherical shape structure with the mean hydrodynamic diameter around 214±11 nm.The drug release was shown to last 20 days,and the MTT assay suggested that drug-loaded GA-ALG nanoparticles had a distinct killing effect on 7703 hepatocellular carcinoma cells.

  5. Variation in breastmilk HIV-1 viral load in left and right breasts during the first 3 months of lactation.

    Science.gov (United States)

    Willumsen, J F; Newell, M L; Filteau, S M; Coutsoudis, A; Dwarika, S; York, D; Tomkins, A M; Coovadia, H M

    2001-09-28

    The mechanism and risk factors associated with mother-to-child transmission of HIV-1 through breastfeeding remain unclear; breastmilk viral load may be an important determinant of transmission. Analysis of breastmilk cell-free viral load in samples taken from each breast at 1, 6 and 14 weeks postpartum showed that HIV-1 is shed intermittently and load may differ considerably between breasts of an individual woman at any given time. Breastmilk HIV-1 load was undetectable in approximately one-third of samples.

  6. Tunable Transmission-Line Metamaterials Mimicking Electromagnetically Induced Transparency

    Science.gov (United States)

    Feng, T. H.; Han, H. P.

    2016-11-01

    Tunable transmission-line (TL) metamaterials mimicking electromagnetically induced transparency (EIT) have been studied. Firstly, two types of tunable TL EIT-like metamaterial, based on the double split-ring resonator (DSRR) and single split-ring resonator (SSRR), were fabricated and their transmission properties carefully compared. The results showed that the transmittance maximum was almost invariable with shift of the transparency window for the tunable DSRR-based TL EIT-like metamaterial, but for the tunable SSRR-based TL EIT-like metamaterial, the transmittance maximum gradually diminished with shift of the transparency window toward the center of the absorption band. Moreover, the reason for these different transmission properties was explored, revealing that the reduction of the transmittance maximum of the transparency window for the tunable SSRR-based TL EIT-like metamaterial is mainly due to energy loss caused by the resistance of the loaded varactor diodes.

  7. Transmission of Sound Through Double-Plate Panel Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens; Domadiya, Parthkumar Gandalal; Andersen, Lars;

    2011-01-01

    In the present paper, a finite-element model of a double-plate panel is implemented to investigate the transmission of sound through a simple lightweight structure. A numerical study is performed of the following three coupling configurations: 1) Structure-borne sound via plate......-stud-plate structures without air inclusions; 2) transmission via the plate-stud-plate structure including the internal acoustic medium; 3) transmission via plate-air-plate connections in a double-leaf panel with no structural coupling between the two plates. A fully coupled analysis is performed in which solid finite...... elements are adopted for the structure, whereas the acoustic medium is discretized into fluid continuum elements. The computations are carried out in frequency domain in the low frequency range and the load acts as a diffuse sound field on one side of the panel....

  8. Impedance matching wireless power transmission system for biomedical devices.

    Science.gov (United States)

    Lum, Kin Yun; Lindén, Maria; Tan, Tian Swee

    2015-01-01

    For medical application, the efficiency and transmission distance of the wireless power transfer (WPT) are always the main concern. Research has been showing that the impedance matching is one of the critical factors for dealing with the problem. However, there is not much work performed taking both the source and load sides into consideration. Both sides matching is crucial in achieving an optimum overall performance, and the present work proposes a circuit model analysis for design and implementation. The proposed technique was validated against experiment and software simulation. Result was showing an improvement in transmission distance up to 6 times, and efficiency at this transmission distance had been improved up to 7 times as compared to the impedance mismatch system. The system had demonstrated a near-constant transfer efficiency for an operating range of 2cm-12cm.

  9. 负载下焊接加固通信铁塔轴力构件非线性屈曲性能研究%Nonlinear Buckling Behavior of Vertical Force Transmission Components of Communications Tower Reinforced by Welding with Initial Compressive Load

    Institute of Scientific and Technical Information of China (English)

    苑士岩; 沈之容

    2015-01-01

    目前,负载下焊接增大截面加固钢结构构件的方法在加固工程中的应用已经非常普遍,为了研究初始负载下焊接加固前后角钢构件的受力特性,运用通用有限元分析软件ANSYS对其进行数值模拟分析。模型考虑初始缺陷以及加固过程中热输入的影响,对不同负载大小及长细比的角钢构件进行非线性屈曲分析。结果表明:采用移动高斯热源模拟焊接加固过程,可以较好的反应实际加固过程;在杆件长细比不变的情况下,随着初始负载的增大,极限承载力逐渐减小;初始负载不变,随着长细比的增大,杆件初始几何弯曲增大,其极限承载力减小。%Nowadays, the method of strengthening steel structural members by increasing the section and welding while under load has been commonly used to strengthen steel structural members in the application of re-inforcement project.In order to study the mechanical characteristics of angle steel members reinforced by welding with initial compressive load, some finite element models were established using ANSYS software considering the influence of initial imperfections and the effect of heat input.The buckling behavior of the reinforced angle steel members for different levels of preloads, and the ratio of slenderness were studied.The welding process was sim-ulated using moving gauss heat source and the satisfactory simulated results were gained.When the slenderness ratio is the same, with the increase of initial load, ultimate bearing capacity decreased gradually.Under the premise of initial load is constant, with the increase of slenderness ratio and initial geometric, the ultimate bear-ing capacity will be decreased.

  10. Prediction of HCV vertical transmission: what factors should be optimized using data mining computational analysis.

    Science.gov (United States)

    Elrazek, Abd; Amer, Mohamed; El-Hawary, Bahaa; Salah, Altaher; Bhagavathula, Akshaya S; Alboraie, M; Saab, Samy

    2017-04-01

    Neonates born to hepatitis C virus (HCV)-positive mothers are usually not screened for HCV. Unscreened children may act as active sources for social HCV transmission, and factors contributing for vertical HCV transmitting still remained controversial and needed optimization. We aimed to investigate the factors contributing for vertical HCV transmission in Egypt; the highest HCV prevalence worldwide. We prospectively followed the neonates born to HCV-positive mother in the child-bearing period, to identify mother-to-child transmission (MTCT) factors from January 2015 to March 2016. Data mining computational analysis was used to quantify the findings. Among 3000 randomized pregnant women, prevalence of HCV was 46/3000 (1.53%). HCV vertical transmission was identified in eight neonates (17.39%). Only high viral load identified at 975.000 IU was the predictor risk for MTCT. Hepatitis C virus in pregnancy has substantial risk for vertical HCV transmission: High viral load in HCV-positive women increases the risk of HCV transmission to neonates. Screening pregnant women during early stage of pregnancy and optimizing the HCV viral load in HCV-positive women might prevent vertical HCV transmission to neonates. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Acoustic data transmission method

    Energy Technology Data Exchange (ETDEWEB)

    Duckworth, A.

    1991-09-17

    This patent describes a method for transmitting time line data through a drillstring having drill pipe sections connected end-to-end by joints from a first location below the surface of the earth to a second location at or near the surface of the earth, the length and cross-sectional area of the drill pipe sections being different from the length and cross-sectional area of the joints. It comprises generating acoustic data signals having a single frequency content in at least one passband of the drillstring; transmitting the data signals through the drillstring from either the first location to the second location or from the second location to the first location during a time period prior to the onset of reflective interference caused by the data signals reflecting from along the length of the drillstring, the time period being equal to or less than the time for the data signals to travel three lengths of the drillstring; stopping the transmission of data signals at the onset of the reflective interference and allowing the acoustic signals to substantially attenuate; and detecting the data signals at the respective first or second location.

  12. EC Transmission Line Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bigelow, Tim S [ORNL

    2012-05-01

    The purpose of this document is to identify materials acceptable for use in the US ITER Project Office (USIPO)-supplied components for the ITER Electron cyclotron Heating and Current Drive (ECH&CD) transmission lines (TL), PBS-52. The source of material property information for design analysis shall be either the applicable structural code or the ITER Material Properties Handbook. In the case of conflict, the ITER Material Properties Handbook shall take precedence. Materials selection, and use, shall follow the guidelines established in the Materials Assessment Report (MAR). Materials exposed to vacuum shall conform to the ITER Vacuum Handbook. [Ref. 2] Commercial materials shall conform to the applicable standard (e.g., ASTM, JIS, DIN) for the definition of their grade, physical, chemical and electrical properties and related testing. All materials for which a suitable certification from the supplier is not available shall be tested to determine the relevant properties, as part of the procurement. A complete traceability of all the materials including welding materials shall be provided. Halogenated materials (example: insulating materials) shall be forbidden in areas served by the detritiation systems. Exceptions must be approved by the Tritium System and Safety Section Responsible Officers.

  13. Evaluation of self-assembled HCPT-loaded PEG- b-PLA nanoparticles by comparing with HCPT-loaded PLA nanoparticles

    Science.gov (United States)

    Yang, Xiangrui; Wu, Shichao; Wang, Yange; Li, Yang; Chang, Di; Luo, Yin; Ye, Shefang; Hou, Zhenqing

    2014-12-01

    We present a dialysis technique to prepare the 10-hydroxycamptothecin (HCPT)-loaded nanoparticles (NPs) using methoxypolyethylene glycol-poly( d, l-lactide) (PEG- b-PLA) and PLA, respectively. Both HCPT-loaded PEG- b-PLA NPs and HCPT-loaded PLA NPs were characterized by differential scanning calorimetry (DSC), dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The results showed that the HCPT-loaded PEG- b-PLA NPs and HCPT-loaded PLA NPs presented a hydrodynamic particle size of 120.1 and 226.8 nm, with a polydispersity index of 0.057 and 0.207, a zeta potential of -31.2 and -45.7 mV, drug encapsulation efficiency of 44.52% and 44.94%, and drug-loaded content of 7.42% and 7.49%, respectively. The HCPT-loaded PEG- b-PLA NPs presented faster drug release rate compared to the HCPT-loaded PLA NPs. The HCPT-loaded PEG- b-PLA NPs presented higher cytotoxicity than the HCPT-loaded PLA NPs. These results suggested that the HCPT-loaded PEG- b-PLA NPs presented better characteristics for drug delivery compared to HCPT-loaded PLA NPs.

  14. Evaluation of self-assembled HCPT-loaded PEG-b-PLA nanoparticles by comparing with HCPT-loaded PLA nanoparticles.

    Science.gov (United States)

    Yang, Xiangrui; Wu, Shichao; Wang, Yange; Li, Yang; Chang, Di; Luo, Yin; Ye, Shefang; Hou, Zhenqing

    2014-12-01

    We present a dialysis technique to prepare the 10-hydroxycamptothecin (HCPT)-loaded nanoparticles (NPs) using methoxypolyethylene glycol-poly(D,L-lactide) (PEG-b-PLA) and PLA, respectively. Both HCPT-loaded PEG-b-PLA NPs and HCPT-loaded PLA NPs were characterized by differential scanning calorimetry (DSC), dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The results showed that the HCPT-loaded PEG-b-PLA NPs and HCPT-loaded PLA NPs presented a hydrodynamic particle size of 120.1 and 226.8 nm, with a polydispersity index of 0.057 and 0.207, a zeta potential of -31.2 and -45.7 mV, drug encapsulation efficiency of 44.52% and 44.94%, and drug-loaded content of 7.42% and 7.49%, respectively. The HCPT-loaded PEG-b-PLA NPs presented faster drug release rate compared to the HCPT-loaded PLA NPs. The HCPT-loaded PEG-b-PLA NPs presented higher cytotoxicity than the HCPT-loaded PLA NPs. These results suggested that the HCPT-loaded PEG-b-PLA NPs presented better characteristics for drug delivery compared to HCPT-loaded PLA NPs.

  15. Planetary Gear Profile Modification Design Based on Load Sharing Modelling

    Institute of Scientific and Technical Information of China (English)

    IGLESIAS Miguel; FERNÁNDEZ DEL RINCÓN Alfonso; DE-JUAN Ana Magdalena; GARCIA Pablo; DIEZ Alberto; VIADERO Fernando

    2015-01-01

    In order to satisfy the increasing demand on high performance planetary transmissions, an important line of research is focused on the understanding of some of the underlying phenomena involved in this mechanical system. Through the development of models capable of reproduce the system behavior, research in this area contributes to improve gear transmission insight, helping developing better maintenance practices and more efficient design processes. A planetary gear model used for the design of profile modifications ratio based on the levelling of the load sharing ratio is presented. The gear profile geometry definition, following a vectorial approach that mimics the real cutting process of gears, is thoroughly described. Teeth undercutting and hypotrochoid definition are implicitly considered, and a procedure for the incorporation of a rounding arc at the tooth tip in order to deal with corner contacts is described. A procedure for the modeling of profile deviations is presented, which can be used for the introduction of both manufacturing errors and designed profile modifications. An easy and flexible implementation of the profile deviation within the planetary model is accomplished based on the geometric overlapping. The contact force calculation and dynamic implementation used in the model are also introduced, and parameters from a real transmission for agricultural applications are presented for the application example. A set of reliefs is designed based on the levelling of the load sharing ratio for the example transmission, and finally some other important dynamic factors of the transmission are analyzed to assess the changes in the dynamic behavior with respect to the non-modified case. Thus, the main innovative aspect of the proposed planetary transmission model is the capacity of providing a simulated load sharing ratio which serves as design variable for the calculation of the tooth profile modifications.

  16. Three-Phase Load Flow for Unbalanced Systems.

    Science.gov (United States)

    Chang, Yih-Ping

    Traditionally, transmission systems are assumed to be balanced in power system analysis. A single phase positive sequence circuit is used in transmission system load flow analysis to simplify the study. However, when untransposed transmission lines are used in a power system due to economic considerations, space limitation; or when large unbalanced load is on the system; or when an unbalance contingency occurs on the system, this assumption may not hold true. The unbalance condition in some isolated systems are so precarious that disaster can result. One such incident occurred on a generator unit of the third nuclear power plant of Taipower in 1985. In that particular case, the turbine blades were broken and a spark ignited the liquid hydrogen when the blade vibration resonated with the 120.5 Hz rotor current. One cause of this rotor current generation is system unbalance. The unbalanced three-phase load flow program is needed in today's power system analysis. An advanced three-phase unbalanced transmission load flow program, capable of locating the unbalanced problem of large electric network systems, was proposed to be developed and tested in this research. Features of this program include simultaneous power flow of multiple voltage levels on an individual phase basis; PV bus generator, cogenerator, transformer simulation, and load modeling. It is found that delta-grounded wye step-up transformer reduces the convergence speed greatly. When too many delta-grounded wye step-up transformers exist in a large scale system and a quick approximate result of the unbalance conditions is needed, these step-up transformers can be substituted by grounded-wye to grounded-wye type transformers. This is tested on a Taipower system case which included 345KV, 161KV and 69KV feeders, network transformers, 34 PV bus generators and 188 three-phase buses. Impending unbalance problems in Taipower system were located. When not too many delta-grounded wye type transformers are in the

  17. HVDC power transmission technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hauth, R.L.; Tatro, P.J.; Railing, B.D. [New England Power Service Co., Westborough, MA (United States); Johnson, B.K.; Stewart, J.R. [Power Technologies, Inc., Schenectady, NY (United States); Fink, J.L.

    1997-04-01

    The purpose of this study was to develop an assessment of the national utility system`s needs for electric transmission during the period 1995-2020 that could be met by future reduced-cost HVDC systems. The assessment was to include an economic evaluation of HVDC as a means for meeting those needs as well as a comparison with competing technologies such as ac transmission with and without Flexible AC Transmission System (FACTS) controllers. The role of force commutated dc converters was to be assumed where appropriate. The assessment begins by identifying the general needs for transmission in the U.S. in the context of a future deregulated power industry. The possible roles for direct current transmission are then postulated in terms of representative scenarios. A few of the scenarios are illustrated with the help of actual U.S. system examples. non-traditional applications as well as traditional applications such as long lines and asynchronous interconnections are discussed. The classical ``break-even distance`` concept for comparing HVDC and ac lines is used to assess the selected scenarios. The impact of reduced-cost converters is reflected in terms of the break-even distance. This report presents a comprehensive review of the functional benefits of HVDC transmission and updated cost data for both ac and dc system components. It also provides some provocative thoughts on how direct current transmission might be applied to better utilize and expand our nation`s increasingly stressed transmission assets.

  18. Probabilistic Capacity Assessment of Lattice Transmission Towers under Strong Wind

    Directory of Open Access Journals (Sweden)

    Wei eZhang

    2015-10-01

    Full Text Available Serving as one key component of the most important lifeline infrastructure system, transmission towers are vulnerable to multiple nature hazards including strong wind and could pose severe threats to the power system security with possible blackouts under extreme weather conditions, such as hurricanes, derechoes, or winter storms. For the security and resiliency of the power system, it is important to ensure the structural safety with enough capacity for all possible failure modes, such as structural stability. The study is to develop a probabilistic capacity assessment approach for transmission towers under strong wind loads. Due to the complicated structural details of lattice transmission towers, wind tunnel experiments are carried out to understand the complex interactions of wind and the lattice sections of transmission tower and drag coefficients and the dynamic amplification factor for different panels of the transmission tower are obtained. The wind profile is generated and the wind time histories are simulated as a summation of time-varying mean and fluctuating components. The capacity curve for the transmission towers is obtained from the incremental dynamic analysis (IDA method. To consider the stochastic nature of wind field, probabilistic capacity curves are generated by implementing IDA analysis for different wind yaw angles and different randomly generated wind speed time histories. After building the limit state functions based on the maximum allowable drift to height ratio, the probabilities of failure are obtained based on the meteorological data at a given site. As the transmission tower serves as the key nodes for the power network, the probabilistic capacity curves can be incorporated into the performance based design of the power transmission network.

  19. Cost and Benefit Analysis of VSC-HVDC Schemes for Offshore Wind Power Transmission

    Institute of Scientific and Technical Information of China (English)

    Sheng WANG; Chunmei FENG; An WEN; Jun LIANG

    2013-01-01

    Due to low load factors of wind power generation,it is possible to reduce transmission capacity to minimize the cost of transmission system construction.Two VSC-HVDC schemes for offshore wind farm,called the point to point (PTP) and DC mesh connections are compared in terms of the utilization of transmission system and its cost.A Weibull distribution is used for estimating offshore wind power generation,besides,the cross correlation between wind farms is considered.The wind energy curtailment is analyzed using the capacity output possibility table (COPT).The system power losses,costs of transmission investment and wind energy curtailment are also computed.A statistic model for the wind generation and transmission is built and simulated in MATLAB to validate the study.It is concluded that a DC mesh transmission can reduce the energy curtailment and power losses.Further benefit is achievable as the wind cross correlation between wind farms decreases.

  20. A radial transmission line material measurement apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Warne, L.K.; Moyer, R.D.; Koontz, T.E.; Morris, M.E.

    1993-05-01

    A radial transmission line material measurement sample apparatus (sample holder, offset short standards, measurement software, and instrumentation) is described which has been proposed, analyzed, designed, constructed, and tested. The purpose of the apparatus is to obtain accurate surface impedance measurements of lossy, possibly anisotropic, samples at low and intermediate frequencies (vhf and low uhf). The samples typically take the form of sections of the material coatings on conducting objects. Such measurements thus provide the key input data for predictive numerical scattering codes. Prediction of the sample surface impedance from the coaxial input impedance measurement is carried out by two techniques. The first is an analytical model for the coaxial-to-radial transmission line junction. The second is an empirical determination of the bilinear transformation model of the junction by the measurement of three full standards. The standards take the form of three offset shorts (and an additional lossy Salisbury load), which have also been constructed. The accuracy achievable with the device appears to be near one percent.

  1. Sikorsky Aircraft Advanced Rotorcraft Transmission (ART) program

    Science.gov (United States)

    Kish, Jules G.

    1993-03-01

    The objectives of the Advanced Rotorcraft Transmission program were to achieve a 25 percent weight reduction, a 10 dB noise reduction, and a 5,000 hour mean time between removals (MTBR). A three engine Army Cargo Aircraft (ACA) of 85,000 pounds gross weight was used as the baseline. Preliminary designs were conducted of split path and split torque transmissions to evaluate weight, reliability, and noise. A split path gearbox was determined to be 23 percent lighter, greater than 10 dB quieter, and almost four times more reliable than the baseline two stage planetary design. Detail design studies were conducted of the chosen split path configuration, and drawings were produced of a 1/2 size gearbox consisting of a single engine path of the split path section. Fabrication and testing was then conducted on the 1/2 size gearbox. The 1/2 size gearbox testing proved that the concept of the split path gearbox with high reduction ratio double helical output gear was sound. The improvements were attributed to extensive use of composites, spring clutches, advanced high hot hardness gear steels, the split path configuration itself, high reduction ratio, double helical gearing on the output stage, elastomeric load sharing devices, and elimination of accessory drives.

  2. Transmission line sag calculations using interval mathematics

    Energy Technology Data Exchange (ETDEWEB)

    Shaalan, H. [Institute of Electrical and Electronics Engineers, Washington, DC (United States)]|[US Merchant Marine Academy, Kings Point, NY (United States)

    2007-07-01

    Electric utilities are facing the need for additional generating capacity, new transmission systems and more efficient use of existing resources. As such, there are several uncertainties associated with utility decisions. These uncertainties include future load growth, construction times and costs, and performance of new resources. Regulatory and economic environments also present uncertainties. Uncertainty can be modeled based on a probabilistic approach where probability distributions for all of the uncertainties are assumed. Another approach to modeling uncertainty is referred to as unknown but bounded. In this approach, the upper and lower bounds on the uncertainties are assumed without probability distributions. Interval mathematics is a tool for the practical use and extension of the unknown but bounded concept. In this study, the calculation of transmission line sag was used as an example to demonstrate the use of interval mathematics. The objective was to determine the change in cable length, based on a fixed span and an interval of cable sag values for a range of temperatures. The resulting change in cable length was an interval corresponding to the interval of cable sag values. It was shown that there is a small change in conductor length due to variation in sag based on the temperature ranges used in this study. 8 refs.

  3. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  4. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  5. The Dynamic Behaviour of Gears with High Transmission Ratio

    Directory of Open Access Journals (Sweden)

    Ivana Atanasovska

    2012-06-01

    Full Text Available This paper describes the dynamic behaviour of helical gears with new standpoint for calculation of influence variables: mesh teeth stiffness, contact lines lengths and load distribution during mesh period. Nonlinear contact Finite Element Analysis and the new iteration procedure are used for calculation of meshed teeth deformations, stiffness and contact loads. The normal load distribution calculated with this procedure is used for evaluation of nonlinear dynamic analytical model of helical gears motion. Described investigation is especially important for gear pairs with high value of transmission ratio, often used in large transport machines. The presented models and results can be used for helical gears modeling when standard procedures don’t cover the requirements.

  6. Regional Transmission Projects: Finding Solutions

    Energy Technology Data Exchange (ETDEWEB)

    The Keystone Center

    2005-06-15

    The Keystone Center convened and facilitated a year-long Dialogue on "Regional Transmission Projects: Finding Solutions" to develop recommendations that will help address the difficult and contentious issues related to expansions of regional electric transmission systems that are needed for reliable and economic transmission of power within and across regions. This effort brought together a cross-section of affected stakeholders and thought leaders to address the problem with the collective wisdom of their experience and interests. Transmission owners sat at the table with consumer advocates and environmental organizations. Representatives from regional transmission organizations exchanged ideas with state and federal regulators. Generation developers explored common interests with public power suppliers. Together, the Dialogue participants developed consensus solutions about how to begin unraveling some of the more intractable issues surrounding identification of need, allocation of costs, and reaching consensus on siting issues that can frustrate the development of regional transmission infrastructure. The recommendations fall into three broad categories: 1. Recommendations on appropriate institutional arrangements and processes for achieving regional consensus on the need for new or expanded transmission infrastructure 2. Recommendations on the process for siting of transmission lines 3. Recommendations on the tools needed to support regional planning, cost allocation, and siting efforts. List of Dialogue participants: List of Dialogue Participants: American Electric Power American Transmission Company American Wind Energy Association California ISO Calpine Corporation Cinergy Edison Electric Institute Environmental Defense Federal Energy Regulatory Commission Great River Energy International Transmission Company ISO-New England Iowa Public Utility Board Kanner & Associates Midwest ISO National Association of Regulatory Utility Commissioners National Association

  7. Energy Transmission and Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Mathison, Jane

    2012-12-31

    The objective of Energy Transmission and Infrastructure Northern Ohio (OH) was to lay the conceptual and analytical foundation for an energy economy in northern Ohio that will: • improve the efficiency with which energy is used in the residential, commercial, industrial, agricultural, and transportation sectors for Oberlin, Ohio as a district-wide model for Congressional District OH-09; • identify the potential to deploy wind and solar technologies and the most effective configuration for the regional energy system (i.e., the ratio of distributed or centralized power generation); • analyze the potential within the district to utilize farm wastes to produce biofuels; • enhance long-term energy security by identifying ways to deploy local resources and building Ohio-based enterprises; • identify the policy, regulatory, and financial barriers impeding development of a new energy system; and • improve energy infrastructure within Congressional District OH-09. This objective of laying the foundation for a renewable energy system in Ohio was achieved through four primary areas of activity: 1. district-wide energy infrastructure assessments and alternative-energy transmission studies; 2. energy infrastructure improvement projects undertaken by American Municipal Power (AMP) affiliates in the northern Ohio communities of Elmore, Oak Harbor, and Wellington; 3. Oberlin, OH-area energy assessment initiatives; and 4. a district-wide conference held in September 2011 to disseminate year-one findings. The grant supported 17 research studies by leading energy, policy, and financial specialists, including studies on: current energy use in the district and the Oberlin area; regional potential for energy generation from renewable sources such as solar power, wind, and farm-waste; energy and transportation strategies for transitioning the City of Oberlin entirely to renewable resources and considering pedestrians, bicyclists, and public transportation as well as drivers

  8. Multitasking metering enhances generation, transmission operations

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, E.

    2008-11-15

    The Dairyland Power Cooperative (DPC) which operates from La Crosse, Wisconsin has the capacity to generate and transmit 1000 MW of power to 25 member cooperatives and 20 municipalities who serve over 500,000 customers. When DPC was experiencing diminished service within its analog cellular-based data communications system, it was presented with an opportunity to install a new automated telecommunications system that would provide secure collection of meter readings from all of its substations. DPC decided to evaluate an advanced multifunctional digital meter from Schweitzer Engineering Laboratories (SEL). The SEL-734 Revenue Metering System offers complete instantaneous metering functions, including voltages, currents, power, energy and power factor. Other capabilities include predictive demand, time-of-use metering, automatic voltage monitoring, harmonics metering and synchrophasor measurement. From a metering perspective, DPC wanted to perform daily load profiles and interval-by-interval metering of their delivery points for billing purposes. They also wanted to provide real-time monitoring of electricity being delivered for both generation and transmission purposes and to make that information available to a distribution SCADA system for their members. The SEL-734 Revenue Meter was well suited to those needs. The SEL-734 provides very high-accuracy energy metering, load profile data collection, instantaneous power measurements, power quality monitoring, and communicates simultaneously over a modem, serial ports, and wide area networks (WAN). The meter is backed with a ten-year warranty as well as field support engineers. 5 figs.

  9. daily nigerian nigerian nigerian peak load forec peak load forec ...

    African Journals Online (AJOL)

    User

    is generally needed for control and scheduling power system and also as inputs to load flo analysis .... Figure 1 Seasonal indices computing neural network ... Feedback paths are sometimes used. In applying a neural network to electric load ...

  10. Load flow analysis using decoupled fuzzy load flow under critical ...

    African Journals Online (AJOL)

    user

    of power system, reliable fuzzy load flow is developed to overcome the limitations of the ... of power mismatches are taken as two inputs for fuzzy logic controller. ..... Programming Based Load Flow Algorithm For Systems Containing Unified ...

  11. A new framework for evaluating along-wind responses of a transmission tower

    Institute of Scientific and Technical Information of China (English)

    Liu Guohuan; Li Hongnan

    2009-01-01

    In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized force spectrum (GFS) model of the transmission tower is deduced; (2) an analytical model that includes the contributions of the higher modes is further derived as a rational algebraic formula to estimate the structural displacement response; and (3) a new approach, applying load with displacement (ALD) instead of force, to solve the internal force of transmission tower is given. Unlike conventional methods, the ALD method can avoid calculating equivalent static wind loads (ESWLs). Finally, a transmission tower structure is used as a numerical example to verify the feasibility and accuracy of the ALD method.

  12. Hepatitis B in pregnancy: a concise review of neonatal vertical transmission and antiviral prophylaxis.

    Science.gov (United States)

    Wong, Frank; Pai, Rohit; Van Schalkwyk, Julie; Yoshida, Eric M

    2014-01-01

    Hepatitis B is a chronic viral infection of the liver leading to complications including cirrhosis and hepatocellular carcinoma. The leading cause of acquisition is vertical transmission from an infected mother to the newborn. Despite newborn immunoprophylaxis, vertical transmission may still occur in 1-14%. The aim of this article is to provide a concise review of the mechanisms and risk factors involved in vertical transmission, as well as prophylactic strategies using immunoprophylaxis and antiviral medications. Mechanisms of vertical transmission include intrauterine and perinatal transfer of virus. High HBV viral load and presence of HBeAg increases risk of transmission. Combination vaccine and hepatitis B immunoglobulin given at birth reduces risk of transmission, as does HBIG given to mothers in the third trimester. Three antivirals have been studied in pregnancy: lamivudine, telbivudine, and tenovofir. All have shown significant reduction in viral loads and vertical transmission and have favorable safety profiles. In conclusion, HBV vertical transmission is preventable through use of immunoprophylaxis and antiviral medications. Recommendation for antiviral use in third trimester in mothers whose HBV VL is greater than 1 x 10⁶ copies/mL.

  13. The evolution of transmission mode

    Science.gov (United States)

    Forbes, Mark R.; Hauffe, Heidi C.; Kallio, Eva R.; Okamura, Beth; Sait, Steven M.

    2017-01-01

    This article reviews research on the evolutionary mechanisms leading to different transmission modes. Such modes are often under genetic control of the host or the pathogen, and often in conflict with each other via trade-offs. Transmission modes may vary among pathogen strains and among host populations. Evolutionary changes in transmission mode have been inferred through experimental and phylogenetic studies, including changes in transmission associated with host shifts and with evolution of the unusually complex life cycles of many parasites. Understanding the forces that determine the evolution of particular transmission modes presents a fascinating medley of problems for which there is a lack of good data and often a lack of conceptual understanding or appropriate methodologies. Our best information comes from studies that have been focused on the vertical versus horizontal transmission dichotomy. With other kinds of transitions, theoretical approaches combining epidemiology and population genetics are providing guidelines for determining when and how rapidly new transmission modes may evolve, but these are still in need of empirical investigation and application to particular cases. Obtaining such knowledge is a matter of urgency in relation to extant disease threats. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289251

  14. Nutrient and Coliform Loading (NCL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of available fecal coliform bacteria, fecal streptococci bacteria, and nutrient loading data. Loading for contaminants other than fecal coliform...

  15. The International Mass Loading Service

    CERN Document Server

    Petrov, Leonid

    2015-01-01

    The International Mass Loading Service computes four loadings: a) atmospheric pressure loading; b) land water storage loading; c) oceanic tidal loading; and d) non-tidal oceanic loading. The service provides to users the mass loading time series in three forms: 1) pre-computed time series for a list of 849 space geodesy stations; 2) pre-computed time series on the global 1deg x 1deg grid; and 3) on-demand Internet service for a list of stations and a time range specified by the user. The loading displacements are provided for the time period from 1979.01.01 through present, updated on an hourly basis, and have latencies 8-20 hours.

  16. Midwest Transmission Workshop I Summary

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Bryan

    2001-05-01

    OAK-B135 The meeting was opened with a review of the purposes of the workshop: (1) Present and discuss key studies and assessments of transmission upgrades, additions and related issues for the upper Midwest, including work that addresses the full range of views on these topics; (2) Understand the various transmission issues in the upper Midwest and discuss options for addressing the issues; and (3) Identify the decision makers and entities that need to play an active role if transmission issues are to be resolved, and agree on next steps for engaging these individuals and organizations through education, outreach, and information dissemination.

  17. Optimized Information Transmission Scheduling Strategy Oriented to Advanced Metering Infrastructure

    Directory of Open Access Journals (Sweden)

    Weiming Tong

    2013-01-01

    Full Text Available Advanced metering infrastructure (AMI is considered to be the first step in constructing smart grid. AMI allows customers to make real-time choices about power utilization and enables power utilities to increase the effectiveness of the regional power grids by managing demand load during peak times and reducing unneeded power generation. These initiatives rely heavily on the prompt information transmission inside AMI. Aiming at the information transmission problem, this paper researches the communication scheduling strategy in AMI at a macroscopic view. First, the information flow of AMI is analyzed, and the power users are classified into several grades by their importance. Then, the defect of conventional information transmission scheduling strategy is analyzed. On this basis, two optimized scheduling strategies are proposed. In the wide area, an optimized scheduling strategy based on user importance and time critical is proposed to guarantee the important power users’ information transmission being handled promptly. In the local area, an optimized scheduling strategy based on device and information importance and time critical is proposed to guarantee the important devices and information in AMI user end system being handled promptly. At last, the two optimized scheduling strategies are simulated. The simulation results show that they can effectively improve the real-time performance and reliability of AMI information transmission.

  18. Allocation of Transmission Cost Using Power Flow Tracing Methods

    Directory of Open Access Journals (Sweden)

    CH Vishnu Vardhan Reddy

    2016-10-01

    Full Text Available In the open access restructured power system market, it is necessary to develop an appropriate pricing scheme that can provide the useful economic information to market participants, such as generation, transmission companies and customers. Though many methods have already been proposed, but accurately estimating and allocating the transmission cost in the transmission pricing scheme is still a challenging task. This work addresses the problem of allocating the cost of the transmission network to generators and demands. In this work four methods using DC Power flow and AC power flow have been attempted. They are MW-Mile Method, MVA-Mile Method, GGDF method and Bialek Tracing method.MVA-Mile method and Bialek Tracing method applies AC power flow and considers apparent power flows. The purpose of the present work is to allocate the cost pertaining to the transmission lines of the network to all the generators and demands. A load flow solution is run and, the proposed method determines how line flows depend on nodal currents. This result is then used to allocate network costs to generators and demands. The technique presented in this work is related to the allocation of the cost to GENCO‘s TRANSCO‘s and DISCO‘s. A technique for tracing the flow of electricity of lines among generators with GGDF and Bialek upstream looking algorithm is proposed. With these methods correct economic signals are generated for all players. All these methods are tested on IEEE 14 bus system

  19. An Approach for Transmission Loss and Cost Allocation by Loss Allocation Index and Co-operative Game Theory

    Science.gov (United States)

    Khan, Baseem; Agnihotri, Ganga; Mishra, Anuprita S.

    2016-03-01

    In the present work authors proposed a novel method for transmission loss and cost allocation to users (generators and loads). In the developed methodology transmission losses are allocated to users based on their usage of the transmission line. After usage allocation, particular loss allocation indices (PLAI) are evaluated for loads and generators. Also Cooperative game theory approach is applied for comparison of results. The proposed method is simple and easy to implement on the practical power system. Sample 6 bus and IEEE 14 bus system is used for showing the effectiveness of proposed method.

  20. Canby Area Service Project substation and associated transmission line. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    Bonneville Power Administration (BPA) provides power to Surprise Valley Electrification Corporation (SVEC) in Modoc County, California. BPA uses PacificCorp`s substation and transmission facilities between Alturas and Canby, California to transfer power to SVEC`s Canby Substation. In the next year, SVEC expects increased industrial, agricultural, and residential electric loads on their 69-kV transmission system south of Canby. SVEC`s substation can accommodate only about 10 percent of the expected additional electric load. BPA`s proposed action is intended to meet SVEC`s increasing electric load. BPA proposes to meet SVEC`s increasing energy load by tapping into BPA`s existing BPA Malin-Warner 230-kV transmission line, and building an 7.9-mile transmission line to a new BPA substation. BPA proposes to build the new substation next to the west side of SVEC`s Canby Substation (Figure 1). This new substation will allow SVEC to move the additional power over their existing transmission or distribution lines. This report is the environmental assessment of the potential impact of the proposed project. The assessment determined that no ``environmental impact statement`` is not required.

  1. Canby Area Service Project : Substation and Associated Transmission Line : Environmental Assessment.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1992-02-01

    Bonneville Power Administration (BPA) provides power to Surprise Valley Electrification Corporation (SVEC) in Modoc County, California. BPA uses PacificCorp's substation and transmission facilities between Alturas and Canby, California to transfer power to SVEC's Canby Substation. In the next year, SVEC expects increased industrial, agricultural, and residential electric loads on their 69-kV transmission system south of Canby. SVEC's substation can accommodate only about 10 percent of the expected additional electric load. BPA's proposed action is intended to meet SVEC's increasing electric load. BPA proposes to meet SVEC's increasing energy load by tapping into BPA's existing BPA Malin-Warner 230-kV transmission line, and building an 7.9-mile transmission line to a new BPA substation. BPA proposes to build the new substation next to the west side of SVEC's Canby Substation (Figure 1). This new substation will allow SVEC to move the additional power over their existing transmission or distribution lines. This report is the environmental assessment of the potential impact of the proposed project. The assessment determined that no environmental impact statement'' is not required.

  2. Android Fully Loaded

    CERN Document Server

    Huddleston, Rob

    2012-01-01

    Fully loaded with the latest tricks and tips on your new Android! Android smartphones are so hot, they're soaring past iPhones on the sales charts. And the second edition of this muscular little book is equally impressive--it's packed with tips and tricks for getting the very most out of your latest-generation Android device. Start Facebooking and tweeting with your Android mobile, scan barcodes to get pricing and product reviews, download your favorite TV shows--the book is positively bursting with practical and fun how-tos. Topics run the gamut from using speech recognition, location-based m

  3. HIV-1 transmitting couples have similar viral load set-points in Rakai, Uganda.

    Directory of Open Access Journals (Sweden)

    T Déirdre Hollingsworth

    2010-05-01

    Full Text Available It has been hypothesized that HIV-1 viral load set-point is a surrogate measure of HIV-1 viral virulence, and that it may be subject to natural selection in the human host population. A key test of this hypothesis is whether viral load set-points are correlated between transmitting individuals and those acquiring infection. We retrospectively identified 112 heterosexual HIV-discordant couples enrolled in a cohort in Rakai, Uganda, in which HIV transmission was suspected and viral load set-point was established. In addition, sequence data was available to establish transmission by genetic linkage for 57 of these couples. Sex, age, viral subtype, index partner, and self-reported genital ulcer disease status (GUD were known. Using ANOVA, we estimated the proportion of variance in viral load set-points which was explained by the similarity within couples (the 'couple effect'. Individuals with suspected intra-couple transmission (97 couples had similar viral load set-points (p = 0.054 single factor model, p = 0.0057 adjusted and the couple effect explained 16% of variance in viral loads (23% adjusted. The analysis was repeated for a subset of 29 couples with strong genetic support for transmission. The couple effect was the major determinant of viral load set-point (p = 0.067 single factor, and p = 0.036 adjusted and the size of the effect was 27% (37% adjusted. Individuals within epidemiologically linked couples with genetic support for transmission had similar viral load set-points. The most parsimonious explanation is that this is due to shared characteristics of the transmitted virus, a finding which sheds light on both the role of viral factors in HIV-1 pathogenesis and on the evolution of the virus.

  4. Hybrid-Vehicle Transmission System

    Science.gov (United States)

    Lupo, G.; Dotti, G.

    1985-01-01

    Continuously-variable transmission system for hybrid vehicles couples internal-combustion engine and electric motor section, either individually or in parallel, to power vehicle wheels during steering and braking.

  5. Transmission line model for nanoelectronics

    Directory of Open Access Journals (Sweden)

    Nelin E. A.

    2009-08-01

    Full Text Available Analytical expressions for resonant parametres and characteristics of typical barrier nanoelectronic structures have been received on the basis of the transmission line model. Characteristics illustrating the efficiency of such approach are presented in the article.

  6. Hybrid-Vehicle Transmission System

    Science.gov (United States)

    Lupo, G.; Dotti, G.

    1985-01-01

    Continuously-variable transmission system for hybrid vehicles couples internal-combustion engine and electric motor section, either individually or in parallel, to power vehicle wheels during steering and braking.

  7. Cultural transmission of civic attitudes.

    Science.gov (United States)

    Miles-Touya, Daniel; Rossi, Máximo

    2016-01-01

    In this empirical paper we attempt to measure the separate influence on civic engagement of educational attainment and cultural transmission of civic attitudes. Unlike most of the previous empirical works on this issue, we are able to approximate the cultural transmission of civic attitudes. We observe that civic returns to education are overstated when the transmission of civic attitudes is ignored. Moreover, the transmission of civic attitudes significantly enhances civic involvement and reinforces civic returns to education. Our findings are in line with the proposals of civic virtue theorists or grass movements who suggest that citizenship education should be included in the compulsory school curricula since, if not, families or local communities will only transmit their particular view of the world.

  8. Factors that affect the fatigue strength of power transmission shafting and their impact on design

    Science.gov (United States)

    Leowenthal, S. H.

    1986-01-01

    A long standing objective in the design of power transmission shafting is to eliminate excess shaft material without compromising operational reliability. A shaft design method is presented which accounts for variable amplitude loading histories and their influence on limited life designs. The effects of combined bending and torsional loading are considered along with a number of application factors known to influence the fatigue strength of shafting materials. Among the factors examined are surface condition, size, stress concentration, residual stress and corrosion fatigue.

  9. Radio and line transmission 2

    CERN Document Server

    Roddy, Dermot

    2013-01-01

    Radio and Line Transmission, Volume 2 gives a detailed treatment of the subject as well as an introduction to additional advanced subject matter. Organized into 14 chapters, this book begins by explaining the radio wave propagation, signal frequencies, and bandwidth. Subsequent chapters describe the transmission lines and cables; the aerials; tuned and coupled circuits; bipolar transistor amplifiers; field-effect transistors and circuits; thermionic valve amplifiers; LC oscillators; the diode detectors and modulators; and the superheterodyne receiver. Other chapters explore noise and interfere

  10. Heartland Alliance for Regional Transmission

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Nancy [Climate and Energy Project, Inc., Hutchinson, KS (United States)

    2017-03-15

    The Heartland Alliance for Regional Transmission (HART) will foster a candid, productive conversation among stakeholders that identifies challenges to and benefits from a massive build out of wind generation and transmission across the Southwest Power Pool. Based on the outcomes of those deliberations, HART will develop and deliver an ambitious, coordinated, peer-to-peer outreach effort that spans the SPP to improve market acceptance for wind.

  11. Advanced Rotorcraft Transmission (ART) program

    Science.gov (United States)

    Heath, Gregory F.; Bossler, Robert B., Jr.

    1993-01-01

    Work performed by the McDonnell Douglas Helicopter Company and Lucas Western, Inc. within the U.S. Army/NASA Advanced Rotorcraft Transmission (ART) Program is summarized. The design of a 5000 horsepower transmission for a next generation advanced attack helicopter is described. Government goals for the program were to define technology and detail design the ART to meet, as a minimum, a weight reduction of 25 percent, an internal noise reduction of 10 dB plus a mean-time-between-removal (MTBR) of 5000 hours compared to a state-of-the-art baseline transmission. The split-torque transmission developed using face gears achieved a 40 percent weight reduction, a 9.6 dB noise reduction and a 5270 hour MTBR in meeting or exceeding the above goals. Aircraft mission performance and cost improvements resulting from installation of the ART would include a 17 to 22 percent improvement in loss-exchange ratio during combat, a 22 percent improvement in mean-time-between-failure, a transmission acquisition cost savings of 23 percent of $165K, per unit, and an average transmission direct operating cost savings of 33 percent, or $24K per flight hour. Face gear tests performed successfully at NASA Lewis are summarized. Also, program results of advanced material tooth scoring tests, single tooth bending tests, Charpy impact energy tests, compact tension fracture toughness tests and tensile strength tests are summarized.

  12. Essays on electricity transmission investment and financial transmission rights

    Science.gov (United States)

    Shang, Wenzhuo

    The U.S. electric power industry has been going through fundamental restructuring and realignment since the 1990's. Many issues and problems have emerged during the transition, and both economists and engineers have been looking for the solutions fervently. In this dissertation, which consists primarily of three essays, we apply economics theory and techniques to the power industry and address two related issues, transmission investment and financial transmission rights (FTRs). The first essay takes the decentralized perspective and investigates the efficiency attribute of market-based transmission investment under perfect competition. We clarify, for the first time, the nature of the externality created by loop flows that causes transmission investment to be inefficient. Our findings have important implications for better understanding of transmission market design and creating incentives for efficient transmission investment. In the second essay, we define several rules for allocating transmission investment cost within the framework of cooperative game theory. These rules provide fair, stable or efficient cost allocations in theory and are good benchmarks against which the allocation mechanism in practice can be compared and improved upon. In the last essay, we make exploratory efforts in analyzing and assessing empirically the performance of the Midwest independent system operator (MISO) FTR auction market. We reveal some stylized facts about this young market and find that it is not efficient under the risk-neutrality assumption. We also point out and correct the drawbacks in previous related work and suggest about more complete empirical work in future. In all, this dissertation makes both theoretic and empirical analysis of the two hot issues related to the power industry and comes up with findings that have important implications for the development of this industry.

  13. Load Control System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  14. Potential Pitfalls in Estimating Viral Load Heritability.

    Science.gov (United States)

    Leventhal, Gabriel E; Bonhoeffer, Sebastian

    2016-09-01

    In HIV patients, the set-point viral load (SPVL) is the most widely used predictor of disease severity. Yet SPVL varies over several orders of magnitude between patients. The heritability of SPVL quantifies how much of the variation in SPVL is due to transmissible viral genetics. There is currently no clear consensus on the value of SPVL heritability, as multiple studies have reported apparently discrepant estimates. Here we illustrate that the discrepancies in estimates are most likely due to differences in the estimation methods, rather than the study populations. Importantly, phylogenetic estimates run the risk of being strongly confounded by unrealistic model assumptions. Care must be taken when interpreting and comparing the different estimates to each other.

  15. Tailoring of electron flow current in magnetically insulated transmission lines

    Directory of Open Access Journals (Sweden)

    J. P. Martin

    2009-03-01

    Full Text Available It is desirable to optimize (minimizing both the inductance and electron flow the magnetically insulated vacuum sections of low impedance pulsed-power drivers. The goal of low inductance is understandable from basic efficiency arguments. The goal of low electron flow results from two observations: (1 flowing electrons generally do not deliver energy to (or even reach most loads, and thus constitute a loss mechanism; (2 energetic electrons deposited in a small area can cause anode damage and anode plasma formation. Low inductance and low electron flow are competing goals; an optimized system requires a balance of the two. While magnetically insulated systems are generally forgiving, there are times when optimization is crucial. For example, in large pulsed-power drivers used to energize high energy density physics loads, the electron flow as a fraction of total current is small, but that flow often reaches the anode in relatively small regions. If the anode temperature becomes high enough to desorb gas, the resulting plasma initiates a gap closure process that can impact system performance. Magnetic-pressure driven (z pinches and material equation of state loads behave like a fixed inductor for much of the drive pulse. It is clear that neither fixed gap nor constant-impedance transmission lines are optimal for driving inductive loads. This work shows a technique for developing the optimal impedance profile for the magnetically insulated section of a high-current driver. Particle-in-cell calculations are used to validate the impedance profiles developed in a radial disk magnetically insulated transmission line geometry. The input parameters are the spacing and location of the minimum gap, the effective load inductance, and the desired electron flow profile. The radial electron flow profiles from these simulations are in good agreement with theoretical predictions when driven at relatively high voltage (i.e., V≥2  MV.

  16. The design of a modified lower limb impactor to assess lower limb injury at typical blast loading rates

    CSIR Research Space (South Africa)

    Pandelani, T

    2014-01-01

    Full Text Available in either amputation or long term physical impairment [1]. The injury to the lower extremity is predominantly as a result of direct load transmission from the deforming vehicle floor which is subjected to the blast load [2]. To quantify the effect of high...

  17. Omega Transmission Lines with Applications to Effective Medium Models of Metamaterials

    CERN Document Server

    Vehmas, Joni; Tretyakov, Sergei

    2014-01-01

    In this paper we introduce the concept of transmission lines with inherent bi-anisotropy and establish an analogy between these lines and volumetric bi-anisotropic materials. In particular, we find under what conditions a periodically loaded transmission line can be treated as an effective omega medium. Two example circuits are introduced and analyzed. The results have two-fold implications: opening a route to emulate electromagnetic properties of bi-anisotropic omega media using transmission-line meshes and understanding and improving effective medium models of composite materials with the use of effective circuit models of unit cells.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Transmission Needs In A Fully Renewable Pan-European Electricity System

    DEFF Research Database (Denmark)

    Rodriguez, Rolando A.; Bruun Andresen, Gorm; Becker, Sarah;

    2012-01-01

    Based on high-resolution weather and electrical load data, the transmission needs for a fully renewable pan-European electricity system are determined. The ideal cross-border transmission capacities turn out to be a factor 10 larger than those of today. A reduction of cross-border transmission...... capacities lead to a non-linear increase of balancing needs. A good compromise turns out to be a capacity layout, which is a factor 5 larger than today’s one. On average each country will only be able to import / export 40% of its residual demand / renewable excess generation....

  20. Influence of load by high power on the optical coupler

    Science.gov (United States)

    Bednarek, Lukas; Poboril, Radek; Vanderka, Ales; Hajek, Lukas; Nedoma, Jan; Vasinek, Vladimir

    2016-12-01

    Nowadays, aging of the optical components is a very current topic. Therefore, some investigations are focused on this area, so that the aging of the optical components is accelerated by thermal, high power and gamma load. This paper deals by findings of the influence of the load by laser with high optical power on the transmission parameters of the optical coupler. The investigated coupler has one input and eight outputs (1x8). Load by laser with high optical power is realized using a fiber laser with a cascade configuration EDFA amplifiers. The output power of the amplifier is approximately 250 mW. Duration of the load is moving from 104 hours to 139 hours. After each load, input power and output powers of all branches are measured. Following parameters of the optical coupler are calculated using formulas: the insertion losses of the individual branches, split ratio, total losses, homogeneity of the losses and cross-talk between different branches. All measurements are performed at wavelengths 1310 nm and 1550 nm. Individual optical powers are measured 20 times, due to the exclusion of statistical error of the measurement. After measuring, the coupler is connected to the amplifier for next cycle of the load. The paper contains an evaluation of the results of the coupler before and after four cycles of the burden.

  1. Multi-band Monopole Antennas Loaded with Metamaterial TL

    Science.gov (United States)

    Song, Zhi-jie; Liang, Jian-gang

    2015-05-01

    A novel metamaterial transmission line (TL) by loading complementary single Archimedean spiral resonator pair (CSASRP) is investigated and used to design a set of multi-frequency monopole antennas. The particularity is that the CSASRP which features dual-shunt branches in the equivalent circuit model is directly etched in the signal strip. By smartly controlling the element parameters, three antennas are designed and one of them covering UMTS and Bluetooth bands is fabricated and measured. The antenna exhibits impedance matching better than -10 dB and normal monopolar radiation patterns at working bands of 1.9-2.22 and 2.38-2.5 GHz. Moreover, the loaded element also contributes to the radiation, which is the major advantage of this prescription over previous lumped-element loadings. The proposed antenna is also more compact over previous designs.

  2. Commercial building energy use monitoring for utility load research

    Energy Technology Data Exchange (ETDEWEB)

    Mazzucchi, R.P.

    1987-01-01

    This paper describes a method to acquire empirical data regarding commercial building energy performance for utility load research. The method was devised and implemented for a large scale monitoring program being conducted for a federal electricity marketing and transmission agency in the Pacific Northwest states. An important feature of this method is its hierarchical approach, wherein building types, end-use loads, and key building characteristics are classified to accommodate analysis at many levels. Through this common taxonomy and measurement protocol, energy-use metering projects of varying detail and comprehensiveness can be coordinated. The procedures devised for this project have been implemented for approximately 150 buildings to date by specially trained contractors. Hence, this paper provides real-world insights of the complexity and power of end use measurements from commercial buildings to address utility load research topics. 6 refs.

  3. On the modelling of excitations in geared systems by transmission errors

    Science.gov (United States)

    Velex, P.; Ajmi, M.

    2006-03-01

    This paper introduces an original theoretical approach to the modelling of pinion-gear excitations valid for three-dimensional models of single-stage geared transmissions. Shape deviations and errors on gears are considered and the associated equations of motion account for time-varying mesh stiffness, and also torsional, flexural and axial couplings. Starting from the instantaneous contact conditions between the teeth, the equations of motion are re-formulated in terms of quasi-static transmission errors under load and no-load transmission errors. The range of application of transmission error-based formulations is analysed and some new equations are proposed which make it possible to introduce rigorously meshing excitations via transmission errors. Using an extended finite element model of a spur and helical gear test rig, the dynamic results from the formulations based on transmission errors are compared with the reference solutions. Both sets of results are found to be in close agreement, thus validating the proposed theory. The paper concludes with a critical analysis of the interests and limitations concerning the concept of transmission errors as excitation terms in gear dynamics.

  4. Transfer Capability Enhancement of Transmission Line using Static Synchronous Compensator (STATCOM

    Directory of Open Access Journals (Sweden)

    Arti Pateriya

    2014-12-01

    Full Text Available Growth of complex electrical power networks introduces lack of controllability of active and reactive power flow in energies networks Power flow control in an existing long transmission line, plays an important role in power system area. This paper employs the shunt connected compensation STATCOM based FACTS devices for the control of voltage and the power flow in long distance transmission line. The proposed device is used in different locations of transmission line and also deals with determination of the optimal location of shunt flexible A.C. transmission line (FACTS devices for a long transmission line for voltage and power transfer improvement. The results also show the line loading and system initial operating conditions. In this paper the two machine 4-bus test system is simulated using MATLAB Simulink environment.

  5. Transfer Capability Enhancement of Transmission Line using Static Synchronous Compensator (STATCOM

    Directory of Open Access Journals (Sweden)

    Arti Pateriya,Nitin Saxena ,Manoj Tiwari

    2012-12-01

    Full Text Available Growth of complex electrical power networks introduces lack of controllability of active and reactive power flow in energies networks Power flow control in an existing long transmission line, plays an important role in power system area. This paper employs the shunt connected compensation STATCOM based FACTS devices for the control of voltage and the power flow in long distance transmission line. The proposed device is used in different locations of transmission line and also deals with determination of the optimal locationof shunt flexible a.c. transmission line (FACTS devices for a long transmission line for voltage and power transfer improvement. The results also showthe line loading and system initial operating conditions. In this paper the two machine 4-bus test system is simulated using MATLAB Simulink environment.

  6. Smart Grid Network Transmission Line RLC Modelling Using Random Power Line Synthesis Scheme

    Directory of Open Access Journals (Sweden)

    Ezennaya S.O

    2013-07-01

    Full Text Available This work proposes Random Power line Synthesis (RPLS as a quicker computational approach to solving RLC parameters of a modern smart grid transmission network. Since modern grid systems provide a holistic perspective of modern grid development, it is obvious that a transmission network that is ageing cannot serve the expanded load demand. The need to revoltionalize the traditional transmission model while exploiting basic electrical theories and principles in Smart Grid (SG architecture necessitated this paper. This work seeks to address the RLC parameter modelling for SG template to provision dynamic power in Nigerian context. Other schemes of transmission RLC modelling were studied as well as outlining their limitations. Consequently, we then proposed a fuzzy smart grid framework for RLC computation and developed a proposed SG overhead transmission line from its conductor characteristics and tower geometry considering the RLC parameters of the conductor while applying RPLS to generate the parameter metrics.

  7. Seismic Performance Research of Transmission Tower in Consideration of the Pile-soil-structure System

    Science.gov (United States)

    Liu, Chuncheng; Mao, Long; Wang, Chongyang; Zha, Chuanming

    2016-11-01

    The seismic performance of transmission tower in consideration of pile-soil- structure dynamic interaction is researched through numerical simulation. Based on a transmission tower of a specific project, pile-soil-transmission tower coupled system is established. By using the method of time history, the pile-soil- transmission tower system dynamic response under seismic load were calculated, and comparing with the results without considering interaction system. Results show that, after considering interaction of the system, the period of the structure have extended and the mode of the structure lagged. On soft sites, compare with no considering the interaction, the results have a big difference, the relative increment of the maximum displacement at the top of the tower is 39.82%, respectively. Therefore it is suggested that the pile-soil-structure dynamic interaction should be fully considered in aseismic design of transmission tower on soft sites and medium soft sites.

  8. Lightly loaded lubricated impacts: Idle gear rattle

    Science.gov (United States)

    Tangasawi, O.; Theodossiades, S.; Rahnejat, H.

    2007-12-01

    Idle gear rattle is associated with the characteristic noise that unselected impacting gears radiate to the environment. It is induced by engine order vibration in the presence of backlash in the unengaged gear pairs, resulting in oscillatory response within their backlash range. A tribo-dynamic model of a front wheel drive manual transmission has been developed to study idle rattle, considering the hydrodynamic contact film reaction and flank friction. The model includes the torsional motions of the idle gears and the lateral motions of the supporting output shafts. The hydrodynamic lubricant film formed between the gear teeth under light impact loads behaves as a nonlinear spring-damper mechanism, whilst the inclusion of the shafts' bearing compliances introduces additional nonlinear terms, which are modelled as piecewise linear functions. The aim of the paper is to extend the existing methodology reported by the authors on idle rattle investigations of geared lubricated systems, based on torsional vibrations only, by considering the system response, which is eventually transferred to the gearbox case through the bearings. These are preliminary results found, which conform closely to experimental measurements taken from a vehicle equipped with a manual transmission of the same type.

  9. Research on Interactive Control of Electrolytic Aluminum Load and Wind Power Output

    Directory of Open Access Journals (Sweden)

    Ge Simin

    2016-01-01

    Full Text Available With the large-scale wind power generation connected to Gansu power grid, electrolytic aluminium load has reached a certain scale at the same time, the vast majority of electrolytic aluminium load directly connects to power grid using 330kV transmission line. According to the physical characteristics and historical data, the continuous adjustment characteristic of electrolytic aluminium load is analysed. Based on this characteristic, a mathematical model for the electrolytic aluminium load is established. Aiming at reducing power network loss and wind power consumption, an optimization model based on the load regulation characteristics of electrolytic aluminium is constructed, which is optimized by particle swarm optimization algorithm. Based on the case data of Gansu power grid, the optimal method based on the load regulation characteristics of electrolytic aluminium is analysed and its feasibility is verified.

  10. Load forecasting for supermarket refrigeration

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Aalborg Nielsen, Henrik

    This report presents a study of models for forecasting the load for supermarket refrigeration. The data used for building the forecasting models consists of load measurements, local climate measurements and weather forecasts. The load measurements are from a supermarket located in a village...... in Denmark. The load for refrigeration is the sum of all cabinets in the supermarket, both low and medium temperature cabinets, and spans a period of one year. As input to the forecasting models the ambient temperature observed near the supermarket together with weather forecasts are used. Every hour...... the hourly load for refrigeration for the following 42 hours is forecasted. The forecast models are adaptive linear time-series models which are fitted with a computationally efficient recursive least squares scheme. The dynamic relations between the inputs and the load is modeled by simple transfer...

  11. Clustering, climate and dengue transmission.

    Science.gov (United States)

    Junxiong, Pang; Yee-Sin, Leo

    2015-06-01

    Dengue is currently the most rapidly spreading vector-borne disease, with an increasing burden over recent decades. Currently, neither a licensed vaccine nor an effective anti-viral therapy is available, and treatment largely remains supportive. Current vector control strategies to prevent and reduce dengue transmission are neither efficient nor sustainable as long-term interventions. Increased globalization and climate change have been reported to influence dengue transmission. In this article, we reviewed the non-climatic and climatic risk factors which facilitate dengue transmission. Sustainable and effective interventions to reduce the increasing threat from dengue would require the integration of these risk factors into current and future prevention strategies, including dengue vaccination, as well as the continuous support and commitment from the political and environmental stakeholders.

  12. Midwest Transmission Workshop III Summary

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Bryan

    2003-03-12

    OAK-B135 On March 12-13, 2002, the National Wind Coordinating Committee (NWCC), in cooperation with regional stakeholders, held a two-day workshop: Planning for Electrical Transmission Needs in the Upper Midwest. The workshop was the outgrowth of an effort to develop a forum and process for consideration of transmission options that strives for equitable allocation of benefits and impacts among all affected parties. The goal of this workshop was to provide a catalyst for an enhanced, inclusive process for transmission planning with participation of and acceptance by all affected stakeholders. Participants in the meeting included representatives of state and regional regulatory agencies, utilities and power generators, the wind industry, environmental and landowner interests, and other interested parties (see Attachment A for a list of meeting participants).

  13. Plasmodium vivax Transmission in Africa.

    Directory of Open Access Journals (Sweden)

    Rosalind E Howes

    2015-11-01

    Full Text Available Malaria in sub-Saharan Africa has historically been almost exclusively attributed to Plasmodium falciparum (Pf. Current diagnostic and surveillance systems in much of sub-Saharan Africa are not designed to identify or report non-Pf human malaria infections accurately, resulting in a dearth of routine epidemiological data about their significance. The high prevalence of Duffy negativity provided a rationale for excluding the possibility of Plasmodium vivax (Pv transmission. However, review of varied evidence sources including traveller infections, community prevalence surveys, local clinical case reports, entomological and serological studies contradicts this viewpoint. Here, these data reports are weighted in a unified framework to reflect the strength of evidence of indigenous Pv transmission in terms of diagnostic specificity, size of individual reports and corroboration between evidence sources. Direct evidence was reported from 21 of the 47 malaria-endemic countries studied, while 42 countries were attributed with infections of visiting travellers. Overall, moderate to conclusive evidence of transmission was available from 18 countries, distributed across all parts of the continent. Approximately 86.6 million Duffy positive hosts were at risk of infection in Africa in 2015. Analysis of the mechanisms sustaining Pv transmission across this continent of low frequency of susceptible hosts found that reports of Pv prevalence were consistent with transmission being potentially limited to Duffy positive populations. Finally, reports of apparent Duffy-independent transmission are discussed. While Pv is evidently not a major malaria parasite across most of sub-Saharan Africa, the evidence presented here highlights its widespread low-level endemicity. An increased awareness of Pv as a potential malaria parasite, coupled with policy shifts towards species-specific diagnostics and reporting, will allow a robust assessment of the public health

  14. Intercultural Transmission and Intergenerational Transmission in Immigrant Families.

    Science.gov (United States)

    Nauck, Bernhard

    2001-01-01

    Examined the impact of intergenerational transmission processes on the intercultural contact and ethnic identification of second generation adolescents from five migrant groups in Germany, distinguishing four possible outcomes of intercultural contact (integration, assimilation, segregation, and marginalization). Data from interviews with same-sex…

  15. Shear loading of costal cartilage

    CERN Document Server

    Subit, Damien

    2014-01-01

    A series of tests were performed on a single post-mortem human subject at various length scales. First, tabletop tests were performed. Next, the ribs and intercostal muscles were tested with the view to characterize the load transfer between the ribs. Finally, the costal cartilage was tested under shear loading, as it plays an important in the transfer of the load between the ribs and the sternum. This paper reports the results of dynamic shear loading tests performed on three samples of costal cartilage harvested from a single post-mortem human subject, as well as the quantification of the effective Young's modulus estimated from the amount of cartilage calcification.

  16. Load forecasting of supermarket refrigeration

    DEFF Research Database (Denmark)

    Rasmussen, Lisa Buth; Bacher, Peder; Madsen, Henrik

    2016-01-01

    This paper presents a novel study of models for forecasting the electrical load for supermarket refrigeration. The data used for building the models consists of load measurements, local climate measurements and weather forecasts. The load measurements are from a supermarket located in a village...... in Denmark. Every hour the hourly electrical load for refrigeration is forecasted for the following 42 h. The forecast models are adaptive linear time series models. The model has two regimes; one for opening hours and one for closing hours, this is modeled by a regime switching model and two different...

  17. Load carriage by infantry soldiers

    Directory of Open Access Journals (Sweden)

    N. C. Majumdar

    1958-07-01

    Full Text Available At constant speed of marching, oxygen consumption has been found to increase linearly with the amount of load carried, indicating that there is no optimum load. However, an optimum speed of marching has been found, depending on the terrain condition. A different line of approach, involving a study of the relationship between stride-length, frequency of stepping and speed in normal walking and the effect of muscular fatigue on this relationship has also yielded similar results. Desirability of further studies on the effect of load on optimum speed of marching, effective reduction of weight of equipment and optimum distribution of load on the body has been stressed.

  18. Boundary stabilization of transmission problems

    Science.gov (United States)

    Cardoso, Fernando; Vodev, Georgi

    2010-02-01

    We study the transmission problem in bounded domains with dissipative boundary conditions. Under some natural assumptions, we prove uniform bounds of the corresponding resolvents on the real axis at high frequency and, as a consequence, we obtain regions free of eigenvalue. To this end, we extend the result of Cardoso et al. ["Distribution of resonances and local energy decay in the transmission problem. II," Math. Res. Lett. 6, 377 (1999)] under more general assumptions. As an application, we get exponential decay of the energy of the solutions of the corresponding mixed boundary value problems.

  19. Transmission pricing: paradigms and methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Shirmohammadi, Dariush [Pacific Gas and Electric Co., San Francisco, CA (United States); Vieira Filho, Xisto; Gorenstin, Boris [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil); Pereira, Mario V.P. [Power System Research, Rio de Janeiro, RJ (Brazil)

    1994-12-31

    In this paper we describe the principles of several paradigms and methodologies for pricing transmission services. The paper outlines some of the main characteristics of these paradigms and methodologies such as where they may be used for best results. Due to their popularity, power flow based MW-mile and short run marginal cost pricing methodologies will be covered in some detail. We conclude the paper with examples of the application of these two pricing methodologies for pricing transmission services in Brazil. (author) 25 refs., 2 tabs.

  20. Electromagnetic Transmission Through Resonant Structures

    Science.gov (United States)

    Young, Steven M.

    Electromagnetic resonators store energy in the form of oscillatory electric and magnetic fields and gradually exchange that energy by coupling with their environment. This coupling process can have profound effects on the transmission and reflection properties of nearby interfaces, with rapid transitions from high transmittance to high reflectance over narrow frequency ranges, and has been exploited to design useful optical components such as spectral filters and dielectric mirrors. This dissertation includes analytic, numeric, and experimental investigations of three different electromagnetic resonators, each based on a different method of confining electromagnetic fields near the region of interest. First, we show that a structure with two parallel conducting plates, each containing a subwavelength slit, supports a localized resonant mode bound to the slits and therefore exhibits (in the absence of nonradiative losses), perfect resonant transmission over a narrow frequency range. In practice, the transmission is limited by conduction losses in the sidewalls; nevertheless, experimental results at 10 GHz show a narrowband transmission enhancement by a factor of 104 compared to the non-resonant transmission, with quality factor (ratio of frequency to peak width) Q ~ 3000. Second, we describe a narrowband transmission filter based on a single-layer dielectric grating. We use a group theory analysis to show that, due to their symmetry, several of the grating modes cannot couple to light at normal incidence, while several others have extremely large coupling. We then show how selectively breaking the system symmetry using off-normal light incidence can produce transmission peaks by enabling weak coupling to some of the previously protected modes. The narrowband filtering capabilities are validated by an experimental demonstration in the long wavelength infrared, showing transmission peaks of quality factor Q ~ 100 within a free-spectral range of 8-15 mum. Third, we

  1. Transmission of electrons inside the cryogenic pumps of ITER injector

    Energy Technology Data Exchange (ETDEWEB)

    Veltri, P., E-mail: pierluigi.veltri@igi.cnr.it; Sartori, E. [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova (Italy)

    2016-02-15

    Large cryogenic pumps are installed in the vessel of large neutral beam injectors (NBIs) used to heat the plasma in nuclear fusion experiments. The operation of such pumps can be compromised by the presence of stray secondary electrons that are generated along the beam path. In this paper, we present a numerical model to analyze the propagation of the electrons inside the pump. The aim of the study is to quantify the power load on the active pump elements, via evaluation of the transmission probabilities across the domain of the pump. These are obtained starting from large datasets of particle trajectories, obtained by numerical means. The transmission probability of the electrons across the domain is calculated for the NBI of the ITER and for its prototype Megavolt ITer Injector and Concept Advancement (MITICA) and the results are discussed.

  2. Transmission of electrons inside the cryogenic pumps of ITER injector.

    Science.gov (United States)

    Veltri, P; Sartori, E

    2016-02-01

    Large cryogenic pumps are installed in the vessel of large neutral beam injectors (NBIs) used to heat the plasma in nuclear fusion experiments. The operation of such pumps can be compromised by the presence of stray secondary electrons that are generated along the beam path. In this paper, we present a numerical model to analyze the propagation of the electrons inside the pump. The aim of the study is to quantify the power load on the active pump elements, via evaluation of the transmission probabilities across the domain of the pump. These are obtained starting from large datasets of particle trajectories, obtained by numerical means. The transmission probability of the electrons across the domain is calculated for the NBI of the ITER and for its prototype Megavolt ITer Injector and Concept Advancement (MITICA) and the results are discussed.

  3. Transmission of Sound Through Double-Plate Panel Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens; Domadiya, Parthkumar Gandalal; Andersen, Lars;

    2011-01-01

    In the present paper, a finite-element model of a single-stud double-plate panel structure is implemented to investigate the transmission of diffuse incident sound waves through typical simple lightweight constructions. A parameter study of the effect of including the internal acoustic medium...... the fluid continuum elements are replaced by a simple spring connection between the two plates. The investigations are performed as parameter studies focusing on the effect of changes in the model. A fully coupled analysis is performed in which solid continuum finite elements are adopted for the structure......, whereas the acoustic medium is discretized into fluid continuum elements. The computations are carried out in frequency domain in the range below 2 kHz and the load acts as an approximated diffuse field on one side of the panel. The results show that if some of the studs are free to bend, the transmission...

  4. EHV/HV Underground Cable Systems for Power Transmission

    DEFF Research Database (Denmark)

    Bak, Claus Leth

    Power transmission is facing its largest challenges ever with regards to handling a transition from today’s fossil‐based power production into renewable sources of generation. We can no longer place power plants close to centres of consumption; they must be located where the natural resources...... the role of interconnecting these generation/load centres, ensuring fair reliability and redundancy of supply. Nowadays, the power transmission system must be able to handle the various sources of renewable generation in a flexible electricity market. This has the consequence that the original layout...... cables is given, and secondly, the modelling approach and validation of this is discussed. Thirdly, making up the main core of the work presented, dynamics of underground cable systems are discussed and important cases to study are highlighted, and next, protection and fault location are discussed...

  5. Enhanced Wireless Power Transmission Using Strong Paramagnetic Response.

    Science.gov (United States)

    Ahn, Dukju; Kiani, Mehdi; Ghovanloo, Maysam

    2014-03-01

    A method of quasi-static magnetic resonant coupling has been presented for improving the power transmission efficiency (PTE) in near-field wireless power transmission, which improves upon the state of the art. The traditional source resonator on the transmitter side is equipped with an additional resonator with a resonance frequency that is tuned substantially higher than the magnetic field excitation frequency. This additional resonator enhances the magnetic dipole moment and the effective permeability of the power transmitter, owing to a phenomenon known as the strong paramagnetic response. Both theoretical calculations and experimental results show increased PTE due to amplification of the effective permeability. In measurements, the PTE was improved from 57.8% to 64.2% at the nominal distance of 15 cm when the effective permeability was 2.6. The power delivered to load was also improved significantly, with the same 10 V excitation voltage, from 0.38 to 5.26 W.

  6. Transmission of Sound Through Double-Plate Panel Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens; Domadiya, Parthkumar Gandalal; Andersen, Lars

    2011-01-01

    In the present paper, a finite-element model of a double-plate panel is implemented to investigate the transmission of sound through a simple lightweight structure. A numerical study is performed of the following three coupling configurations: 1) Structure-borne sound via plate-stud-plate structu......In the present paper, a finite-element model of a double-plate panel is implemented to investigate the transmission of sound through a simple lightweight structure. A numerical study is performed of the following three coupling configurations: 1) Structure-borne sound via plate...... elements are adopted for the structure, whereas the acoustic medium is discretized into fluid continuum elements. The computations are carried out in frequency domain in the low frequency range and the load acts as a diffuse sound field on one side of the panel....

  7. Error Transmission in Video Coding with Gaussian Noise

    Directory of Open Access Journals (Sweden)

    A Purwadi

    2015-06-01

    Full Text Available In video transmission, there is a possibility of packet lost and a large load variation in the bandwidth. These are the sources of network congestion, which can interfere the communication data rate. The coding system used is a video coding standard, which is either MPEG-2 or H.263 with SNR scalability. The algorithm used for motion compensation, temporal redundancy and spatial redundancy is the Discrete Cosine Transform (DCT and quantization. The transmission error is simulated by adding Gaussian noise (error on motion vectors. From the simulation results, the SNR and Peak Signal to Noise Ratio (PSNR in the noisy video frames decline with averages of 3dB and increase Mean Square Error (MSE on video frames received noise.

  8. Optical nonreciprocal transmission in an asymmetric silicon photonic crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zheng; Chen, Juguang; Ji, Mengxi; Huang, Qingzhong; Xia, Jinsong; Wang, Yi, E-mail: yingwu2@126.com, E-mail: ywangwnlo@mail.hust.edu.cn [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wu, Ying, E-mail: yingwu2@126.com, E-mail: ywangwnlo@mail.hust.edu.cn [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

    2015-11-30

    An optical nonreciprocal transmission (ONT) is realized by employing the nonlinear effects in a compact asymmetric direct-coupled nanocavity-waveguide silicon photonic crystal structure with a high loaded quality factor (Q{sub L}) of 42 360 and large extinction ratio exceeding 30 dB. Applying a single step lithography and successive etching, the device can realize the ONT in an individual nanocavity, alleviating the requirement to accurately control the resonance of the cavities. A maximum nonreciprocal transmission ratio of 21.1 dB as well as a working bandwidth of 280 pm in the telecommunication band are obtained at a low input power of 76.7 μW. The calculated results by employing a nonlinear coupled-mode model are in good agreement with the experiment.

  9. Transport composite fuselage technology: Impact dynamics and acoustic transmission

    Science.gov (United States)

    Jackson, A. C.; Balena, F. J.; Labarge, W. L.; Pei, G.; Pitman, W. A.; Wittlin, G.

    1986-01-01

    A program was performed to develop and demonstrate the impact dynamics and acoustic transmission technology for a composite fuselage which meets the design requirements of a 1990 large transport aircraft without substantial weight and cost penalties. The program developed the analytical methodology for the prediction of acoustic transmission behavior of advanced composite stiffened shell structures. The methodology predicted that the interior noise level in a composite fuselage due to turbulent boundary layer will be less than in a comparable aluminum fuselage. The verification of these analyses will be performed by NASA Langley Research Center using a composite fuselage shell fabricated by filament winding. The program also developed analytical methodology for the prediction of the impact dynamics behavior of lower fuselage structure constructed with composite materials. Development tests were performed to demonstrate that the composite structure designed to the same operating load requirement can have at least the same energy absorption capability as aluminum structure.

  10. Transmission needs across a fully renewable European power system

    CERN Document Server

    Rodriguez, Rolando A; Andresen, Gorm B; Heide, Dominik; Greiner, Martin

    2013-01-01

    The residual load and excess power generation of 27 European countries with a 100% penetration of variable renewable energy sources are explored in order to quantify the benefit of power transmission between countries. Estimates are based on extensive weather data, which allows for modelling of hourly mismatches between the demand and renewable generation from wind and solar photovoltaics. For separated countries, balancing is required to cover around 24% of the total annual energy consumption. This number can be reduced down to 15% once all countries are networked together with uncon- strained interconnectors. The reduction represents the maximum possible benefit of transmission for the countries. The total Net Transfer Capacity of the unconstrained interconnectors is roughly twelve times larger than current values. However, constrained interconnector capacities six times larger than the current values are found to provide 97% of the maximum possible benefit of cooperation. This motivates a detailed investig...

  11. Rigorous theoretical derivation of lumped models to transmission line systems

    Institute of Scientific and Technical Information of China (English)

    Zhao Jixiang

    2012-01-01

    By virtue of the negative electric parameter concept,i.e.negative lumped resistance,inductance,conductance and capacitance (N-RLGC),the lumped equivalent models of transmission line systems,including the circuit model,two-port π-network and T-network,are given.We start from the N-segment-ladder-like equivalent networks composed distributed parameters,and achieve the input impedance in the form of a continued fraction.Utilizing the continued fraction theory,the expressions of input impedance are obtained under three kinds of extreme cases,i.e.the load impedances are equal to zero,infinity and characteristic impedance,respectively.When the number of segment N is limited to infinity,they are transformed to lumped elements.Comparison between the distributed model and lumped model of transmission lines,the expression of tanh yd,which is the key term in the transmission line equations,are obtained by RLGC,furthermore,according to input admittance,admittance matrix and ABCD matrix of transmission lines,the lumped equivalent circuit models,π-networks and T-networks have been given.The models are verified in the frequency and time domain,respectively,showing that the models are accurate and efficient.

  12. Demand Response Load Following of Source and Load Systems

    DEFF Research Database (Denmark)

    Hu, Jianqiang; Cao, Jinde; Yong, Taiyou

    2017-01-01

    capacities and regulation rates of aggregators. Based on the evaluation results, the dispatch center optimizes the real time load following trajectories for the generating units and the flexible load agents via look-ahead optimization by considering the injection of renewable power. Furthermore, we mainly...

  13. Muscle as a collagen fiber reinforced composite material: force transmission in muscle and whole limbs

    NARCIS (Netherlands)

    Huijing, P.A.J.B.M.

    1999-01-01

    Even though no direct physiologic evidence proving that myo-tendinous junctions at the end of myofibers are sites of force transmission is available, these locations are accepted to support this function, because its specialized morphology resembles that of load-bearing membranes in structure and lo

  14. Theories and technologies of electronic-electrical-mechanical integrated(EEMI)transmission system

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ EEMI is one of the hot spots in cross-disciplinary research. The research in this topic was to discard the traditional mechanical gear reducer, integrate electrical motor with mechanical load, control the electrical motor by electrical power generated by microelectronics and electrical electronics; namely, form a EEMI transmission system in the mechanical equipments with low rotation rate and large rotation torque.

  15. Eastern Wind Integration and Transmission Study: Executive Summary and Project Overview

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-01-01

    This study evaluates the future operational and integration impacts of three different 20 percent wind energy penetration scenarios and one 30 percent wind penetration scenario, including a high-level analysis of transmission to deliver the wind energy to load centers, in the study year 2024.

  16. The Economics of Storage, Transmission and Drought: Integrating Variable Wind Power into Spatially Separated Electricity Grids

    NARCIS (Netherlands)

    Scora, H.; Sopinka, A.; Kooten, van G.C.

    2012-01-01

    To mitigate the high variability of wind and make it a more viable renewable energy source, observers recommend greater integration of spatially-separated electrical grids, with high transmission lines linking load centers, scattered wind farms and hydro storage sites. In this study, we examine the

  17. Muscle as a collagen fiber reinforced composite material: force transmission in muscle and whole limbs

    NARCIS (Netherlands)

    Huijing, P.A.J.B.M.

    1999-01-01

    Even though no direct physiologic evidence proving that myo-tendinous junctions at the end of myofibers are sites of force transmission is available, these locations are accepted to support this function, because its specialized morphology resembles that of load-bearing membranes in structure and

  18. Controlled loading of building blocks into temporary self-assembled scaffolds for directed assembly of organic nanostructures.

    Science.gov (United States)

    Banner, L Todd; Danila, Delia C; Sharpe, Katie; Durkin, Melissa; Clayton, Benjamin; Anderson, Ben; Richter, Andrew; Pinkhassik, Eugene

    2008-10-21

    Using temporary self-assembled scaffolds to preorganize building blocks is a potentially powerful method for the synthesis of organic nanostructures with programmed shapes. We examined the underlying phenomena governing the loading of hydrophobic monomers into lipid bilayer interior and demonstrated successful control of the amount and ratio of loaded monomers. When excess styrene derivatives or acrylates were added to the aqueous solution of unilamellar liposomes made from saturated phospholipids, most loading occurs within the first few hours. Dynamic light scattering and transmission electron microscopy revealed no evidence of aggregation caused by monomers. Bilayers appeared to have a certain capacity for accommodating monomers. The total volume of loaded monomers is independent of monomer structure. X-ray scattering showed the increase in bilayer thickness consistent with loading monomers into bilayer interior. Loading kinetics is inversely proportional to the hydrophobicity and size of monomers. Loading and extraction kinetic data suggest that crossing the polar heads region is the rate limiting step. Consideration of loading kinetics and multiple equilibria are important for achieving reproducible monomer loading. The total amount of monomers loaded into the bilayer can be controlled by the loading time or length of hydrophobic lipid tails. The ratio of loaded monomers can be varied by changing the ratio of monomers used for loading or by the time-controlled replacement of a preloaded monomer. Understanding and controlling the loading of monomers into bilayers contributes to the directed assembly of organic nanostructures.

  19. TE_01 High Power Disk Loaded Guide Load

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, Z.D.; /SLAC

    2005-06-01

    A method to design a matching section from a smooth guide to a disk-loaded guide, using a variation of broadband matching, [1, 2] is described. Using this method, we show how to design high power loads, attenuators and filters. The load consists of a disk-loaded coaxial guide operating in the TE{sub 01}-mode. We use this mode because it has no electric field terminating on a conductor, has no axial currents, and has no current at the cylinder-disk interface. A high power load design that has -35 dB reflection and a 200 MHz, -20 dB bandwidth, is presented. It is expected that it will carry the 600 MW output peak power of the pulse compression network. We use coaxial geometry and stainless steel material to increase the attenuation per cell.

  20. Combining multiple single-reference transmissibility functions in a unique matrix formulation for operational modal analysis

    Science.gov (United States)

    Devriendt, C.; Weijtjens, W.; De Sitter, G.; Guillaume, P.

    2013-10-01

    In recent years, the authors have proposed an innovative approach for Operational Modal Analysis based on transmissibility measurements. A method was proposed based on combining 2 single-reference transmissibility functions that were obtained during 2 different loading conditions. However in practice one in general has access to multiple transmissibility functions and perhaps even multiple loading conditions. In this paper a new method is introduced that combines all the measured single-reference transmissibility functions in a unique matrix formulation in order to identify system poles. It will be shown that each element of the pseudo-inverse of this matrix is a rational function with poles equal to the system poles. The proposed method reduces the risk to miss system poles and to identify extra non-physical poles. Therefore the method increases the usability and reliability of transmissibility based operational modal analysis (TOMA). The method will be demonstrated and validated by means of an experiment on a beam excited at multiple inputs for three different loading conditions.

  1. An HIV epidemic model based on viral load dynamics: value in assessing empirical trends in HIV virulence and community viral load.

    Science.gov (United States)

    Herbeck, Joshua T; Mittler, John E; Gottlieb, Geoffrey S; Mullins, James I

    2014-06-01

    Trends in HIV virulence have been monitored since the start of the AIDS pandemic, as studying HIV virulence informs our understanding of HIV epidemiology and pathogenesis. Here, we model changes in HIV virulence as a strictly evolutionary process, using set point viral load (SPVL) as a proxy, to make inferences about empirical SPVL trends from longitudinal HIV cohorts. We develop an agent-based epidemic model based on HIV viral load dynamics. The model contains functions for viral load and transmission, SPVL and disease progression, viral load trajectories in multiple stages of infection, and the heritability of SPVL across transmissions. We find that HIV virulence evolves to an intermediate level that balances infectiousness with longer infected lifespans, resulting in an optimal SPVL∼4.75 log10 viral RNA copies/mL. Adaptive viral evolution may explain observed HIV virulence trends: our model produces SPVL trends with magnitudes that are broadly similar to empirical trends. With regard to variation among studies in empirical SPVL trends, results from our model suggest that variation may be explained by the specific epidemic context, e.g. the mean SPVL of the founding lineage or the age of the epidemic; or improvements in HIV screening and diagnosis that results in sampling biases. We also use our model to examine trends in community viral load, a population-level measure of HIV viral load that is thought to reflect a population's overall transmission potential. We find that community viral load evolves in association with SPVL, in the absence of prevention programs such as antiretroviral therapy, and that the mean community viral load is not necessarily a strong predictor of HIV incidence.

  2. An HIV epidemic model based on viral load dynamics: value in assessing empirical trends in HIV virulence and community viral load.

    Directory of Open Access Journals (Sweden)

    Joshua T Herbeck

    2014-06-01

    Full Text Available Trends in HIV virulence have been monitored since the start of the AIDS pandemic, as studying HIV virulence informs our understanding of HIV epidemiology and pathogenesis. Here, we model changes in HIV virulence as a strictly evolutionary process, using set point viral load (SPVL as a proxy, to make inferences about empirical SPVL trends from longitudinal HIV cohorts. We develop an agent-based epidemic model based on HIV viral load dynamics. The model contains functions for viral load and transmission, SPVL and disease progression, viral load trajectories in multiple stages of infection, and the heritability of SPVL across transmissions. We find that HIV virulence evolves to an intermediate level that balances infectiousness with longer infected lifespans, resulting in an optimal SPVL∼4.75 log10 viral RNA copies/mL. Adaptive viral evolution may explain observed HIV virulence trends: our model produces SPVL trends with magnitudes that are broadly similar to empirical trends. With regard to variation among studies in empirical SPVL trends, results from our model suggest that variation may be explained by the specific epidemic context, e.g. the mean SPVL of the founding lineage or the age of the epidemic; or improvements in HIV screening and diagnosis that results in sampling biases. We also use our model to examine trends in community viral load, a population-level measure of HIV viral load that is thought to reflect a population's overall transmission potential. We find that community viral load evolves in association with SPVL, in the absence of prevention programs such as antiretroviral therapy, and that the mean community viral load is not necessarily a strong predictor of HIV incidence.

  3. A modular restoration tower for electric power line transmission

    Energy Technology Data Exchange (ETDEWEB)

    Nicolazzi, L.C.; Pereira, J.C.; Leonel, C.E.L.; Rocha, G.B.; Bianchezzi, V.; Mendes, F. [Universidade Federal Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica], Emails: lauro@grante.ufsc.br, jcarlos@grante.ufsc.br; Luz, R.L. [ELETROSUL Centrais Eletricas S.A., Florianopolis, SC (Brazil)], Email: rluz@eletrosul.gov.br

    2009-07-01

    The main target of this R and D project is to develop an restoration tower for electric energy lines transmission. Whereas these towers should present the main features like transport facility, easiest assembling associated with a low cost of manufacture, it was applied the single-column tower concepts supported by stays, modularized, framed and articulated at the base. The concepts used for this development was a design methodology. From the different definition situations of load, numerical models have been developed focusing the design to the best of structural element arrangements of its modules. Then, tests were performed in laboratory to determine the module structural performance for different work load situations. These tests served to identify inconsistencies in the numerical models and proposed adjustments in its design to improve its performance on the strength and stability. (author)

  4. Immediate Versus Early Loading and Conventional Loading in Implant Dentistry

    Directory of Open Access Journals (Sweden)

    Hassan Maghaireh

    2013-12-01

    Full Text Available To minimize the risk of implant failures after their placement, dental implants are traditionally kept load-free for 3 to 8 months to establish osseointegration before connecting the prosthetic super-structure (conventional loading. However, implant dentists are under continuous pressure from the media and patients to speed up the treatment and reduce number of visits during the implant therapy. Immediate implant loading can also reduce the cost and might also improve aesthetics as claimed by some surgeons. This pressure from the media, patients and dentists was behind introducing changes into the loading protocols and nowadays implants are loaded early and even immediately and it would be useful to know whether there is a difference in success rates between immediately and early loaded implants compared with conventionally loaded implants. It is well known that whenever a clinician is faced with a clinical question, the answer(s should be evidence based to avoid the risk of bias as opinion based answers can be misleading and can cause more failures in the dental practice. This mini-review aims to evaluate the effects of (1 immediate (within 1 week, (2 early (between 1 week and 2 months, and (3 conventional (after 2 months loading of osseointegrated dental implants. The review found no evidence that attaching artificial teeth either immediately, after 6 weeks (early or after at least 3 months (conventional led to any important differences in the failure of the implant or the artificial tooth, or to the amount of bone which surrounded the implant (any bone loss would be an undesirable consequence. However, we found a trend of more failures and complications with early loading when compared to immediate or conventional loading. More research is needed in this area. - See more at: http://smiledentaljournal.com/article.php?id=59#sthash.mniQLIcf.dpuf

  5. Optimal load shedding and restoration

    Science.gov (United States)

    Xu, Ding

    Load shedding is an emergency control action in power systems that can save systems from a wide-area blackout. Underfrequency load shedding, steady state load shedding, and voltage load shedding are widely used in power systems. These methods utilize either the steady state model or a simplified dynamic model to represent a power systems. In this dissertation, a general optimal load shedding method that considers both the dynamic process and load distribution is proposed. The unfavorable load shedding is then formulated as an optimization problem with the objective function of cost minimization. This objective function is subjected to system, security, and operation constraints. The entire problem becomes a question of optimization with differential and nonlinear equations as constraints. To solve this problem, discretization is used to change the differential equations into algebraic equations. The original problem is thus reformulated as an optimization problem and can be solved by a standard mathematical program. The general idea is then applied to traditional power systems, deregulated power systems, power systems with distributed generation, and load restoration. In the traditional power system, the method shows that governor action, generation dynamic, disturbance location, and economic factors can be taken into consideration. In the deregulated power system, two power market models are developed and incorporated into the load shedding scheme. In power systems with multiple distributed generations, the different cases of disturbances are analyzed and models of different distributed generation developed. The general idea is then applied. Finally, the load restoration problem is studied, and it is proposed that an optimization method be applied to it. This dissertation provides a comprehensive solution for load shedding problem in power systems. The models developed in this research can also be used to study other power system problems.

  6. Research Overview on Wireless Power Transmission Technology

    OpenAIRE

    Li Tao; Wu Liheng; Chen Zheng

    2015-01-01

    According to the latest researches, this paper outlines the development of wireless power transmission and introduces the latest applications of wireless power transmission in life. To describe the wireless power transmission technologies in detail, the paper presents the short-range, medium-range and remote wireless power transmission, respectively. In addition, the paper also depicts some unique properties of wireless power transmission system to make readers understand WPT system better. A...

  7. VIDEO TRANSMISSION SYSTEM IN ITV APPLICATION

    Institute of Scientific and Technical Information of China (English)

    WangYancai; WangQunwei; WangZhaohui

    1996-01-01

    The transmission characteristics of video transmission mediums,coaxial cable and optical fiber ,are discussed in the paper. The formulas for frequency bandwidthare given to evaluate the video transmission distance. For typical video transmissionsystems with BB/IM and PFM/IM using optical fiber as the channel, expressions andcalculating results for both SIN and sensitivity are given. Finally. the principle for selecting different type of transmission systems according to transmission distances of the industrial TV is presented.

  8. Transmission characteristics of BSE transponder

    Science.gov (United States)

    Yamamoto, M.; Fukuchi, H.; Kozu, T.; Igarashi, M.; Takeuchi, M.

    1986-01-01

    The transmission characteristics of the BSE transponder and their variation with the passage of time measured during the period from the beginning of BSE operation, May 1978 to March 1979, were previously reported. In this paper, the subsequent investigation completed by the time of the failure of the last high power amplifier of 100 watts of the BSE, June 1980, is discussed.

  9. Money and transmission of bacteria

    NARCIS (Netherlands)

    Gedik, H.; Voss, T.A.; Voss, A.

    2013-01-01

    Money is one of the most frequently passed items in the world. The aim of this study was to ascertain the survival status of bacteria including Staphylococcus aureus, Escherichia coli, and Vancomycin- Resistant Enterococci (VRE) on banknotes from different countries and the transmission of bacteria

  10. Transmission analysis in WDM networks

    DEFF Research Database (Denmark)

    Rasmussen, Christian Jørgen

    1999-01-01

    This thesis describes the development of a computer-based simulator for transmission analysis in optical wavelength division multiplexing networks. A great part of the work concerns fundamental optical network simulator issues. Among these issues are identification of the versatility and user...... with a view of reducing the required number of bits....

  11. Wireless Power Transmission Using Microwaves

    Directory of Open Access Journals (Sweden)

    Nikhil B. Dhake

    2012-04-01

    Full Text Available In this paper, we present the concept of wireless power transmission to cut the clutter or lead to clean sources of electricity. It will eradicate the hazardous usage of electrical wires which involve lot of confusion in particularly organizing them. The plan is transmitting power as microwaves from one place to another in order to reduce the use of clumsy wires

  12. Microstructured Surfaces for Enhanced Transmission

    DEFF Research Database (Denmark)

    Ivinskaya, Aliaksandra; Bergmann, René; Kafka, Jan Robert;

    2014-01-01

    Binary microstructures are used to increase transmission of silicon (Si) surfaces in the infrared (IR) range. We consider hexagonal and square lattices with square and round pillars with the finitedifference frequency-domain (FDFD) method. In agreement with theory and previous publications, the h...

  13. Norovirus transmission on cruise ship.

    Science.gov (United States)

    Isakbaeva, Elmira T; Widdowson, Marc-Alain; Beard, R Suzanne; Bulens, Sandra N; Mullins, James; Monroe, Stephan S; Bresee, Joseph; Sassano, Patricia; Cramer, Elaine H; Glass, Roger I

    2005-01-01

    An outbreak of norovirus gastroenteritis affected passengers on two consecutive cruises of ship X and continued on 4 subsequent cruises despite a 1-week sanitization. We documented transmission by food and person-to-person contact; persistence of virus despite sanitization onboard, including introductions of new strains; and seeding of an outbreak on land.

  14. Characterization of nanomaterials with transmission electron microscopy

    KAUST Repository

    Anjum, Dalaver H.

    2016-08-01

    The field of nanotechnology is about research and development on materials whose at least one dimension is in the range of 1 to 100 nanometers. In recent years, the research activity for developing nano-materials has grown exponentially owing to the fact that they offer better solutions to the challenges faced by various fields such as energy, food, and environment. In this paper, the importance of transmission electron microscopy (TEM) based techniques is demonstrated for investigating the properties of nano-materials. Specifically the nano-materials that are investigated in this report include gold nano-particles (Au-NPs), silver atom-clusters (Ag-ACs), tantalum single-atoms (Ta-SAs), carbon materials functionalized with iron cobalt (Fe-Co) NPs and titania (TiO2) NPs, and platinum loaded Ceria (Pt-CeO2) Nano composite. TEM techniques that are employed to investigate nano-materials include aberration corrected bright-field TEM (BF-TEM), high-angle dark-field scanning TEM (HAADF-STEM), electron energy-loss spectroscopy (EELS), and BF-TEM electron tomography (ET). With the help presented of results in this report, it is proved herein that as many TEM techniques as available in a given instrument are essential for a comprehensive nano-scale analysis of nanomaterials.

  15. A Q-Modulation Technique for Efficient Inductive Power Transmission.

    Science.gov (United States)

    Kiani, Mehdi; Lee, Byunghun; Yeon, Pyungwoo; Ghovanloo, Maysam

    2015-12-01

    A fully-integrated power management ASIC for efficient inductive power transmission has been presented capable of automatic load transformation using a method, called Q-modulation. Q-modulation is an adaptive scheme that offers load matching against a wide range of loading (RL ) and coupling distance (d23 ) variations in inductive links to maintain high power transfer efficiency (PTE). It is suitable for inductive powering implantable microelectronic devices (IMDs), recharging mobile electronics, and electric vehicles. In Q-modulation, the zero-crossings of the induced current in the receiver (Rx) LC-tank are detected and a low-loss switch chops the Rx LC-tank for part of the power carrier cycle to form a high-Q LC-tank and store the maximum energy, which is then transferred to RL by opening the switch. By adjusting the duty cycle (D), the loaded-Q of the Rx LC-tank can be dynamically modulated to compensate for variations in RL . A Q-modulation power management (QMPM) prototype chip was fabricated in a 0.35-μm standard CMOS process, occupying 4.8 mm(2). In a 1.45 W wireless power transfer setup, using a class-E power amplifier (PA) operating at 2 MHz, the QMPM successfully increased the inductive link PTE and the overall power efficiency by 98.5% and 120.7% at d23 = 8 cm, respectively, by compensating for 150 Ω variation in RL at D = 45%.

  16. Load identification during object handling

    NARCIS (Netherlands)

    Kortier, H.G.; Veltink, P.H.

    2011-01-01

    In this paper a new concept to identify environ- mental loads during the interaction with the human body by sensing interface forces and movement is proposed. Mass and spring loads were moved by hand over a fixed height difference. Kinematic and kinetic quantities were measured between the hand and

  17. Loading Conditions and Longitudinal Strength

    DEFF Research Database (Denmark)

    Sørensen, Herman

    1995-01-01

    Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength.......Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength....

  18. Loading Conditions and Longitudinal Strength

    DEFF Research Database (Denmark)

    Sørensen, Herman

    1995-01-01

    Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength.......Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength....

  19. LOAD MANAGEMENT IN CLOUD ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Esha Sarkar

    2014-09-01

    Full Text Available Cloud computing is an on demand service in which shared resources, information, software and other devices are provided to the end user as per their requirement at a specific time. A cloud consists of several elements such as clients, datacenters and distributed servers. There are n number of clients and end users involved in cloud environment. These clients may make requests to the cloud system simultaneously, making it difficult for the cloud to manage the entire load at a time. The load can be CPU load, memory load, delay or network load. This might cause inconvenience to the clients as there may be delay in the response time or it might affect the performance and efficiency of the cloud environment. So, the concept of load balancing is very important in cloud computing to improve the efficiency of the cloud. Good load balancing makes cloud computing more efficient and improves user satisfaction. This paper gives an approach to balance the incoming load in cloud environment by making partitions of the public cloud

  20. Transplacental transmission of Human Papillomavirus

    Directory of Open Access Journals (Sweden)

    Serafini Eduardo P

    2008-09-01

    Full Text Available Abstract This paper aimed at studying the transplacental transmission of HPV and looking at the epidemiological factors involved in maternal viral infection. The following sampling methods were used: (1 in the pregnant woman, (a genital; (b peripheral blood; (2 in the newborn, (a oral cavity, axillary and inguinal regions; (b nasopharyngeal aspirate, and (c cord blood; (3 in the placenta. The HPV DNA was identified using two methods: multiplex PCR of human β-globin and of HPV using the PGMY09 and PGMY11 primers; and nested-PCR, which combines degenerated primers of the E6/E7 regions of the HPV virus, that allowed the identification of genotypes 6/11, 16, 18, 31, 33, 42, 52 and 58. Transplacental transmission was considered when type-specific HPV concordance was found between the mother, the placenta and the newborn or the mother and cord blood. The study included 49 HPV DNA-positive pregnant women at delivery. Twelve placentas (24.5%, n = 12/49 had a positive result for HPV DNA. Eleven newborn were HPV DNA positive in samples from the nasopharyngeal or buccal and body or cord blood. In 5 cases (10.2%, n = 5/49 there was HPV type-specific agreement between genital/placenta/newborn samples. In one case (2%, n = 1/49 there was type specific HPV concordance between genital/cord blood and also suggested transplacental transmission. A positive and significant correlation was observed between transplacental transmission of HPV infection and the maternal variables of immunodepression history (HIV, p = 0.011. In conclusion the study suggests placental infection in 23.3% of the cases studied and transplacental transmission in 12.2%. It is suggested that in future HPV DNA be researched in the normal endometrium of women of reproductive age. The possible consequence of fetal exposure to HPV should be observed.

  1. Umbilical Cable Recovery Load Analysis

    Institute of Scientific and Technical Information of China (English)

    YAN Shu-wang; JIA Zhao-lin; FENG Xiao-wei; LI Shi-tao

    2013-01-01

    Umbilical cable is a kind of integrated subsea cable widely used in the exploration and exploitation of oil and gas field.The severe ocean environment makes great challenges to umbilical maintenance and repair work.Damaged umbilical is usually recovered for the regular operation of the offshore production system.Analysis on cables in essence is a two-point boundary problem.The tension load at the mudline must be known first,and then the recovery load and recovery angle on the vessel can be solved by use of catenary equation.The recovery analysis also involves umbilicalsoil interaction and becomes more complicated.Calculation methods for recovery load of the exposed and buried umbilical are established and the relationship between the position of touch down point and the recovery load as well as the recovery angle and recovery load are analyzed.The analysis results provide a theoretical reference for offshore on-deck operation.

  2. Umbilical cable recovery load analysis

    Science.gov (United States)

    Yan, Shu-wang; Jia, Zhao-lin; Feng, Xiao-wei; Li, Shi-tao

    2013-06-01

    Umbilical cable is a kind of integrated subsea cable widely used in the exploration and exploitation of oil and gas field. The severe ocean environment makes great challenges to umbilical maintenance and repair work. Damaged umbilical is usually recovered for the regular operation of the offshore production system. Analysis on cables in essence is a two-point boundary problem. The tension load at the mudline must be known first, and then the recovery load and recovery angle on the vessel can be solved by use of catenary equation. The recovery analysis also involves umbilical-soil interaction and becomes more complicated. Calculation methods for recovery load of the exposed and buried umbilical are established and the relationship between the position of touch down point and the recovery load as well as the recovery angle and recovery load are analyzed. The analysis results provide a theoretical reference for offshore on-deck operation.

  3. Wind load reduction for heliostats

    Energy Technology Data Exchange (ETDEWEB)

    Peterka, J.A.; Hosoya, N.; Bienkiewicz, B.; Cermak, J.E.

    1986-05-01

    This report presents the results of wind-tunnel tests supported through the Solar Energy Research Institute (SERI) by the Office of Solar Thermal Technology of the US Department of Energy as part of the SERI research effort on innovative concentrators. As gravity loads on drive mechanisms are reduced through stretched-membrane technology, the wind-load contribution of the required drive capacity increases in percentage. Reduction of wind loads can provide economy in support structure and heliostat drive. Wind-tunnel tests have been directed at finding methods to reduce wind loads on heliostats. The tests investigated primarily the mean forces, moments, and the possibility of measuring fluctuating forces in anticipation of reducing those forces. A significant increase in ability to predict heliostat wind loads and their reduction within a heliostat field was achieved.

  4. HIV transmission law in the age of treatment-as-prevention.

    Science.gov (United States)

    Haire, Bridget; Kaldor, John

    2015-12-01

    Evidence that treating people with HIV early in infection prevents transmission to sexual partners has reframed HIV prevention paradigms. The resulting emphasis on HIV testing as part of prevention strategies has rekindled the debate as to whether laws that criminalise HIV transmission are counterproductive to the human rights-based public health response. It also raises normative questions about what constitutes 'safe(r) sex' if a person with HIV has undetectable viral load, which has significant implications for sexual practice and health promotion. This paper discusses a recent high-profile Australian case where HIV transmission or exposure has been prosecuted, and considers how the interpretation of law in these instances impacts on HIV prevention paradigms. In addition, we consider the implications of an evolving medical understanding of HIV transmission, and particularly the ability to determine infectiousness through viral load tests, for laws that relate to HIV exposure (as distinct from transmission) offences. We conclude that defensible laws must relate to appreciable risk. Given the evidence that the transmissibility of HIV is reduced to negligible level where viral load is suppressed, this needs to be recognised in the framing, implementation and enforcement of the law. In addition, normative concepts of 'safe(r) sex' need to be expanded to include sex that is 'protected' by means of the positive person being virally suppressed. In jurisdictions where use of a condom has previously mitigated the duty of the person with HIV to disclose to a partner, this might logically also apply to sex that is 'protected' by undetectable viral load. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  5. Behaviour of Single Pile in Reinforced Slope Subjected to Inclined Load

    Directory of Open Access Journals (Sweden)

    Dr. A. I. Dhatrak

    2016-09-01

    Full Text Available Deep foundations, including driven piles, are used to support vertical loads of structures and lateral forces. Typical structures subjected to lateral loads include bridge abutments, transmission tower, sand offshore platforms. Traffic, wind, wave, and seismic forces are common types of lateral loads subjected to pile foundations. The present work is focused on understanding the lateral load capacity of vertical piles located near crest of the slope and subjected to the lateral and inclined loads. The experimental investigation was carried out to study the effect of reinforcing an earth slope on the inclined loading behavior of a single vertical pile located near the slope. Layers of geogrid were used to reinforce a sandy slope of 1V:2H. The parametric studies were performed by varying the length of pile(L, angle of inclination of load (θ, number of geogrid reinforcement (Nr and crest distance. It was observed that the lateral load capacity of pile depends upon these parameters. The lateral load capacity of pile increases with increase in inclination of load, length of pile(L, number of geogrid reinforcement (Nr and crest distance.

  6. The singular point transition concept: A novel continuously variable transmission comprising planetary gear trains and a variator

    Science.gov (United States)

    Gomà Ayats, J. R.; Diego-Ayala, U.; Artes, F. Fenollosa

    2012-01-01

    The singular point transition concept relates a novel type of continuously variable transmission. This transmission comprises a pair of planetary gear trains and a couple of electric motors, used to control the overall speed ratio. Its singularity lies in the topology of operation, with less than 10% of nominal power circulating through the electric path. This low power level is achieved by segmenting the range of operation of the transmission. To validate this technology, a test bed was built. The transmission presented here is able to provide any output/input speed ratio within the interval of 0:1.55, meaning that it also offers the function of an infinite variable transmission. Description of the system and results of experimental tests are presented. The results showed that the transmission is able to function in the whole range of operation. They also showed that under load conditions the fraction of power transmitted through the electric path is maintained around the design value.

  7. Lumped transmission line avalanche pulser

    Science.gov (United States)

    Booth, Rex

    1995-01-01

    A lumped linear avalanche transistor pulse generator utilizes stacked transistors in parallel within a stage and couples a plurality of said stages, in series with increasing zener diode limited voltages per stage and decreasing balanced capacitance load per stage to yield a high voltage, high and constant current, very short pulse.

  8. Usage of Lightning Arrester Line to Feed Light Electrical Loads

    Directory of Open Access Journals (Sweden)

    Hani B. Odeh

    2009-01-01

    Full Text Available In remote areas, light loads (tens of kilowatts are scattered and situated in the field of high voltage lines (66KV and above. These loads are very far from the main feeders/sub-stations (33KV-0.380KV. Feeding such loads in the traditional ways like provision of Diesel-Powered Stations, installation of new distribution lines from the Feeding Centers, or building new Sub-Stations are not practical ways from the economical point of view, because it requires huge additional expenses and will increase electrical power losses. These expenses are not worthy for such loads and therefore, it is necessary to search for other methods to supply them. One of these methods is to use the lightning arrester line as capacitive divider to supply the light loads. In this research, the induced voltage of the lightning arrester line was calculated when it is isolated from the earth. We found the capacitance between lightning arrester line versus the phases and lightning arrester. It was also found the selective power out of the lightning arrester line and the required length which is to be isolated from the earth keeping the main function of the lightning arrester line. When economically comparing between supplying the light electrical loads by traditional ways and the method of lightning arrester, it was found the advantage of using lightning arresters to supply such loads. Also, by using the traditional methods, it was noted that there is a power loss in the power transmission lines by a percentage of 1.8%.

  9. Quasi monolithic silicon load cell for loads up to 1000 kg with insensitivity to non-homogeneous load distributions

    NARCIS (Netherlands)

    Wiegerink, Remco; Zwijze, Robert; Krijnen, Gijs; Lammerink, Theo; Elwenspoek, Miko

    2000-01-01

    In this paper, a micromachined silicon load cell (force sensor) is presented for measuring loads up to 1000 kg. The sensitive surface of 1 cm2 contains a matrix of capacitive sensing elements to make the load cell insensitive to non-homogeneous load distributions. The load cell has been realized and

  10. 75 FR 37883 - Transmission Planning and Cost Allocation by Transmission Owning and Operating Public Utilities

    Science.gov (United States)

    2010-06-30

    ... planning processes provide an incumbent transmission owner with an unfair advantage over merchant and... provider with an undue advantage over a nonincumbent transmission developer. Neither incumbent nor... that provides an incumbent utility with an undue advantage over nonincumbent transmission project...

  11. 76 FR 49841 - Transmission Planning and Cost Allocation by Transmission Owning and Operating Public Utilities

    Science.gov (United States)

    2011-08-11

    ... process, procedures for joint evaluation and sharing of information regarding the respective transmission... data and information between neighboring transmission planning regions at least annually. 9. Finally... of power flows over an interconnected transmission system. In particular, the...

  12. The Atlas load protection switch

    CERN Document Server

    Davis, H A; Dorr, G; Martínez, M; Gribble, R F; Nielsen, K E; Pierce, D; Parsons, W M

    1999-01-01

    Atlas is a high-energy pulsed-power facility under development to study materials properties and hydrodynamics experiments under extreme conditions. Atlas will implode heavy liner loads (m~45 gm) with a peak current of 27-32 MA delivered in 4 mu s, and is energized by 96, 240 kV Marx generators storing a total of 23 MJ. A key design requirement for Atlas is obtaining useful data for 95601130f all loads installed on the machine. Materials response calculations show current from a prefire can damage the load requiring expensive and time consuming replacement. Therefore, we have incorporated a set of fast-acting mechanical switches in the Atlas design to reduce the probability of a prefire damaging the load. These switches, referred to as the load protection switches, short the load through a very low inductance path during system charge. Once the capacitors have reached full charge, the switches open on a time scale short compared to the bank charge time, allowing current to flow to the load when the trigger pu...

  13. Immediate loading of dental implants.

    Science.gov (United States)

    Henry, P J; Liddelow, G J

    2008-06-01

    The purpose of this review is to explore the concept of immediate loading as it pertains to dental implants and the indications for clinical practice. The definition of immediate loading will be considered together with a review of the relevant literature in an attempt to provide evidence-based guidelines for successful implementation into practice. A search of electronic databases including Medline, PubMed and the Cochrane Database of Systematic Reviews was undertaken using the terms "immediate loading'', "dental implants'', "immediate function'', "early loading'', "oral implants'', "immediate restoration'' and "systematic review''. This was supplemented by handsearching in peer-reviewed journals and cross-referenced with the articles accessed. Emphasis was given to systematic reviews and controlled clinical trials. A definition of immediate loading was suggested pertinent to the realities of logistics in clinical practice with respect to application and time frame. The literature was evaluated and shown to be limited with significant shortcomings. Guidelines and recommendations for clinical protocols were suggested and illustrated by examples of case types with a minimum of 1-3 years follow-up. A list of additional references for further reading was provided. Within the limitations of this review, there is evidence to suggest that immediate loading protocols have demonstrated high implant survival rates and may be cautiously recommended for certain clinical situations. However, more high level evidence studies, preferably randomized controlled trials (RCTs), over a long time frame are required to show a clear benefit over more conventional loading protocols.

  14. Vertical transmission of hepatitis C virus: Current knowledge and perspectives

    Institute of Scientific and Technical Information of China (English)

    Chun-Yan; Yeung; Hung-Chang; Lee; Wai-Tao; Chan; Chun-Bin; Jiang; Szu-Wen; Chang; Chih-Kuang; Chuang

    2014-01-01

    Hepatitis C virus(HCV) infection is a major global health issue.Infection by the HCV can cause acute and chronic liver diseases and may lead to cirrhosis,hepatocellular carcinoma or liver failure.The World Health Organization estimates that approximately 3% of the world population have been infected with HCVand the worldwide prevalence is between 1% and 8% in pregnant women and between 0.05% and 5% in children.Following the introduction of blood product screening,vertical transmission becomes the leading cause of childhood HCV infection.The prevalence of pediatric HCV infection varies from 0.05% to 0.36% in developed countries and between 1.8% and 5% in the developing world.All children born to women with antiHCV antibodies should be checked for HCV infection.Though universal screening is controversial,selective antenatal HCV screening on high-risk populations is highly recommended and should be tested probably.Multiple risk factors were shown to increase the possibility of HCV vertical transmission,including coinfections with human immunodeficiency virus,intravenous drug use and elevated maternal HCV viral load,while breastfeeding and HCV genotypes have been studied to have little impact.At present,no clinical intervention has been clearly studied and proved to reduce the HCV vertical transmission risk.Cesarean section should not be recommended as a procedure to prevent vertical transmission,however,breastfeeding is generally not forbidden.The high prevalence of global HCV infection necessitates renewed efforts in primary prevention,including vaccine development,as well as new approaches to reduce the burden of chronic liver disease.Future researches should focus on the interruption of vertical transmission,developments of HCV vaccine and directacting antivirals in infancy and early childhood.

  15. Transmission capacity of wireless networks

    CERN Document Server

    Weber, Steven

    2012-01-01

    Transmission capacity (TC) is a performance metric for wireless networks that measures the spatial intensity of successful transmissions per unit area, subject to a constraint on the permissible outage probability (where outage occurs when the SINR at a receiver is below a threshold). This volume gives a unified treatment of the TC framework that has been developed by the authors and their collaborators over the past decade. The mathematical framework underlying the analysis (reviewed in Ch. 2) is stochastic geometry: Poisson point processes model the locations of interferers, and (stable) shot noise processes represent the aggregate interference seen at a receiver. Ch. 3 presents TC results (exact, asymptotic, and bounds) on a simple model in order to illustrate a key strength of the framework: analytical tractability yields explicit performance dependence upon key model parameters. Ch. 4 presents enhancements to this basic model --- channel fading, variable link distances, and multi-hop. Ch. 5 presents four...

  16. Stream Control Transmission Protocol Steganography

    CERN Document Server

    Fraczek, Wojciech; Szczypiorski, Krzysztof

    2010-01-01

    Stream Control Transmission Protocol (SCTP) is a new transport layer protocol that is due to replace TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) protocols in future IP networks. Currently, it is implemented in such operating systems like BSD, Linux, HP-UX or Sun Solaris. It is also supported in Cisco network devices operating system (Cisco IOS) and may be used in Windows. This paper describes potential steganographic methods that may be applied to SCTP and may pose a threat to network security. Proposed methods utilize new, characteristic SCTP features like multi-homing and multistreaming. Identified new threats and suggested countermeasures may be used as a supplement to RFC 5062, which describes security attacks in SCTP protocol and can induce further standard modifications.

  17. Transmission of Influenza A Viruses

    Science.gov (United States)

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  18. Terahertz metamaterial with asymmetric transmission

    CERN Document Server

    Singh, R; Menzel, C; Rockstuhl, C; Azad, A K; Cheville, R A; Lederer, F; Zhang, W; Zheludev, N I

    2009-01-01

    We show for the first time that a planar metamaterial, an array of coupled metal split-ring resonators with a unit cell lacking mirror symmetry, exhibits asymmetric transmission of terahertz radiation propagating through it in opposite directions. This intriguing effect, that is compatible with Lorentz reciprocity and time-reversal, depends on a directional difference in conversion efficiency of the incident circularly polarized wave into one of opposite handedness, that is only possible in lossy low-symmetry planar chiral metamaterials. We show that asymmetric transmission is linked to excitation of enantiomerically sensitive plasmons, these are induced charge-field excitations that depend on the mutual handedness of incident wave and metamaterial pattern. Various bands of positive, negative and zero phase and group velocities have been identified indicating the opportunity to develop polarization sensitive negative index and slow light media based on such metamaterials.

  19. Transmission of influenza A viruses.

    Science.gov (United States)

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-05-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to 'novel' viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages.

  20. Exploiting a Transmission Grating Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Ronald E. Bell

    2004-12-08

    The availability of compact transmission grating spectrometers now allows an attractive and economical alternative to the more familiar Czerny-Turner configuration for many high-temperature plasma applications. Higher throughput is obtained with short focal length refractive optics and stigmatic imaging. Many more spectra can be obtained with a single spectrometer since smaller, more densely packed optical input fibers can be used. Multiple input slits, along with a bandpass filter, can be used to maximize the number of spectra per detector, providing further economy. Curved slits can correct for the strong image curvature of the short focal length optics. Presented here are the governing grating equations for both standard and high-dispersion transmission gratings, defining dispersion, image curvature, and desired slit curvature, that can be used in the design of improved plasma diagnostics.

  1. Load Estimation from Modal Parameters

    DEFF Research Database (Denmark)

    Aenlle, Manuel López; Brincker, Rune; Fernández, Pelayo Fernández;

    2007-01-01

    In Natural Input Modal Analysis the modal parameters are estimated just from the responses while the loading is not recorded. However, engineers are sometimes interested in knowing some features of the loading acting on a structure. In this paper, a procedure to determine the loading from a FRF...... matrix assembled from modal parameters and the experimental responses recorded using standard sensors, is presented. The method implies the inversion of the FRF which, in general, is not full rank matrix due to the truncation of the modal space. Furthermore, some ecommendations are included to improve...

  2. Transmission risk of human trichinellosis.

    Science.gov (United States)

    Takumi, Katsuhisa; Teunis, Peter; Fonville, Manoj; Vallee, Isabelle; Boireau, Pascal; Nöckler, Karsten; van der Giessen, Joke

    2009-02-23

    Trichinella is a food-borne parasitic zoonoses and human cases are still reported in Europe mainly due to the consumption of pig meat originating from small backyard farms. Infections originating from industrialized pig farming have not been reported for decades in Europe, due to control measures to prevent the transmission of Trichinella from wildlife by indoor housing and good management practices. Therefore, risk-based monitoring programs might replace individual carcass control in industrialized pig farming as described in EU legislation SANCO 2075/2005. Transmission of Trichinella species between wildlife and the risk that may pose to humans via consumption of contaminated pork meat has not been studied quantitatively. One pathway by which human trichinellosis can occur is the rat-pig-human route. To evaluate the transmission risk though this pathway the dose responses of rat, pig, and human were studied. Experimental T. spiralis infection was performed in rats with doses of as few as 10 parasites and the data set was analysed using a newly developed dose response model that describes larvae per gram (LPG). Experimental T. spiralis infection in pig was analysed in a similar way. Furthermore nine published outbreaks of human trichinellosis were analysed to determine the dose response in humans. The risk of human trichinellosis via the rat-pig-human transmission was simulated by the Monte Carlo method. A pair of female and male parasites representing the lowest infection pressure from the environment, led to the probability of human trichinellosis by consumption of 100g of raw pork meat equal to 5% via the studied rat-pig-human pathway. In the absence of rodent control near the farm, a low infection pressure from wildlife presents a relatively high risk of human trichinellosis via consumption of uncooked pork meat.

  3. Monitoring Atmospheric Transmission with FLAME

    Science.gov (United States)

    Zimmer, Peter C.; McGraw, J. T.; Zirzow, D. C.; Koppa, M.; Buttler-Pena, K.

    2014-01-01

    Calibration of ground-based observations in the optical and near-infrared requires precise and accurate understanding of atmospheric transmission, at least as precise and accurate as that required for the spectral energy distributions of science targets. Traditionally this has used the Langley extrapolation method, observing targets and calibrators over a range of airmass and extrapolating to zero airmass by assuming a plane-parallel homogeneous atmosphere. The technique we present uses direct measurements of the atmosphere to derive the transmission along the line of sight to science targets at a few well-chosen wavelengths. The Facility Lidar Atmospheric Monitor of Extinction (FLAME) is a 0.5m diameter three Nd:YAG wavelength (355nm, 532nm & 1064nm) elastic backscatter lidar system. Laser pulses are transmitted into the atmosphere in the direction of the science target. Photons scattered back toward the receiver by molecules, aerosols and clouds are collected and time-gated so that the backscatter intensity is measured as a function of range to the scattering volume. The system is housed in a mobile calibration lab, which also contains auxiliary instrumentation to provide a NIST traceable calibration of the transmitted laser power and receiver efficiency. FLAME was designed to create a million photons per minute signal from the middle stratosphere, where the atmosphere is relatively calm and dominated by molecules of the well-mixed atmosphere (O2 & N2). Routine radiosonde measurements of the density at these altitudes constrain the scattering efficiency in this region and, combined with calibration of the transmitter and receiver, the only remaining unknown quantity is the two-way transmission to the stratosphere. These measurements can inform atmospheric transmission models to better understand the complex and ever-changing observatory radiative transfer environment. FLAME is currently under active development and we present some of our ongoing measurements.

  4. Advanced Rotorcraft Transmission program summary

    Science.gov (United States)

    Bossler, Robert B., Jr.; Heath, Gregory F.

    1992-07-01

    The current status of the Advanced Rotorcraft Transmission (ART) program is reviewed. The discussion includes a general configuration and face gear description, weight analysis, stress analysis, reliability analysis, acoustic analysis, face gear testing, and planned torque split testing. Design descriptions include the face gear webs sized for equal stiffness, a positive engagement clutch, the lubrication system, and a high contact ratio planetary. Test results for five gear materials and three housing materials are presented.

  5. Analysis of Wireless Power Transmission

    OpenAIRE

    2013-01-01

    The advent of various wireless technologies have revolutionized the communication infrastructure and consequently changed the entire world into a global village. Use of wireless technology has also been made for transmission of electric power wirelessly. It increases the portability of power systems and integrates the communication technologies and electric power to the same platform. This paper presents a comprehensive review and detailed analysis of various techniques used for wireless powe...

  6. Transmission and distribution electrical engineering

    CERN Document Server

    Bayliss, Colin

    2003-01-01

    This comprehensive treatment of the theory and practice encountered in the installation and design of transmission and distribution systems for electrical power has been updated and revised to provide the project engineer with all the latest, relevant information to design and specify the correct system for a particular application.Thoroughly updated and revised to include latest developmentsLearn from and Author with extensive experience in managing international projectsFind out the reasoning and implicatons behind the different specifications and methods

  7. ac transmission line field measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kotter, F.R.; Misakian, M.

    1977-11-01

    The concern in recent years over the environmental effects of electric and magnetic fields from high voltage transmission lines has also focused attention on the accuracy of measurements of these fields. Electric field meters are discussed in terms of theory of operation, parameters affecting performance, meter performance under field and laboratory conditions, and calibration procedures. The performance and calibration of magnetic field meters is described. (LCL)

  8. METHODS OF POLYMODAL INFORMATION TRANSMISSION

    Directory of Open Access Journals (Sweden)

    O. O. Basov

    2015-03-01

    Full Text Available The research results upon the application of the existing information transmission methods in polymodal info communication systems are presented herein. The analysis of the existing commutation ways and multiplexing schemes has revealed that modern means of telecommunication are capable of providing polymodal information delivery with the required quality to the customer correspondent terminal. Under these conditions substantial capacity resource consumption in the data transmission networks with a simultaneous static time multiplexing is required, however, it is easier to achieve the modality synchronization within that kind of an infrastructure. The data networks with a static time multiplexing demand employing more sophisticated supporting algorithms of the guaranteed data blocks delivery quality. However, due to the stochastic data blocks delays modality synchronizing during the off-line processing is more difficult to provide. Nowadays there are objective preconditions for a data networking realization which is invariable to the applied transmission technology. This capability is defined by a wide (person-to-person application of the optical technologies in the transport infrastructure of the polymodal info communication systems. In case of the availability of the customer terminal and networking functioning matching mode it becomes possible to organize channels in the latter which can adaptively select the most effective networking technology according to the current volume allocation and modality types in the messages.

  9. Automatic Transmission Of Liquid Nitrogen

    Directory of Open Access Journals (Sweden)

    Sumedh Mhatre

    2015-08-01

    Full Text Available Liquid Nitrogen is one of the major substance used as a chiller in industry such as Ice cream factory Milk Diary Storage of blood sample Blood Bank etc. It helps to maintain the required product at a lower temperature for preservation purpose. We cannot fully utilise the LN2 so practically if we are using 3.75 litre LN2 for a single day then around 12 of LN2 450 ml is wasted due to vaporisation. A pressure relief valve is provided to create a pressure difference. If there is no pressure difference between the cylinder carrying LN2 and its surrounding it will results in damage of container as well as wastage of LN2.Transmission of LN2 from TA55 to BA3 is carried manually .So care must be taken for the transmission of LN2 in order to avoid its wastage. With the help of this project concept the transmission of LN2 will be carried automatically so as to reduce the wastage of LN2 in case of manual operation.

  10. Power Load Management as a Computational Market

    NARCIS (Netherlands)

    Ygge, Fredrik; Akkermans, Hans; Akkermans, J.M.

    1997-01-01

    Power load management enables energy utilities to reduce peak loads and thereby save money. Due to the large number of different loads, power load management is a complicated optimization problem. We present a new decentralized approach to this problem by modeling direct load management as a

  11. Probabilistic Meteorological Characterization for Turbine Loads

    DEFF Research Database (Denmark)

    Kelly, Mark C.; Larsen, Gunner Chr.; Dimitrov, Nikolay Krasimirov;

    2014-01-01

    Beyond the existing, limited IEC prescription to describe fatigue loads on wind turbines, we look towards probabilistic characterization of the loads via analogous characterization of the atmospheric flow, particularly for today's "taller" turbines with rotors well above the atmospheric surface....... These are used as input to loads calculation, and with a statistical loads output description, they allow for improved design and loads calculations....

  12. Power Load Management as a Computational Market

    NARCIS (Netherlands)

    Ygge, F.; Akkermans, J.M.

    1996-01-01

    Power load management enables energy utilities to reduce peak loads and thereby save money. Due to the large number of different loads, power load management is a complicated optimization problem. We present a new decentralized approach to this problem by modeling direct load management as a computa

  13. Power Load Management as a Computational Market

    NARCIS (Netherlands)

    Ygge, Fredrik; Akkermans, Hans

    1997-01-01

    Power load management enables energy utilities to reduce peak loads and thereby save money. Due to the large number of different loads, power load management is a complicated optimization problem. We present a new decentralized approach to this problem by modeling direct load management as a computa

  14. Methodology for the calculation of load limits; Metodologia para o calculo de limites de carregamento

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Dorel Soares [Companhia Energetica de Sao Paulo, SP (Brazil); Bezerra, Luis Roberto [FURNAS Centrias Eletricas S.A., Rio de Janeiro, RJ (Brazil); Gesualdi Junior, Luis Carlos [Light Servicos de Eletricidade SA, Rio de Janeiro, RJ (Brazil); Portela, Carlos Medeiros

    1987-10-01

    The maximization of the usage of the equipment and therefore, the reduction in the investments in the expansion of electric power transmission systems has been a great worry to the Brazilian electric power system. This work describes a digital simmulation methodology to the evaluation of load limits in transformers 16 refs.

  15. Non-spherical voids and lattice reorientation patterning in a shock-loaded Al single crystal

    DEFF Research Database (Denmark)

    Hong, Chuanshi; Fæster, Søren; Hansen, Niels

    2017-01-01

    An Al single crystal shock loaded in the direction and captured at incipient spallation was examined by combining X-ray tomography, electron backscatter diffraction on a scanning electron microscope, and transmission electron microscopy (TEM). Octahedral voids with {1 1 1} faces were...

  16. The dispersive properties of a dielectricrod loaded waveguide immersed in a magnetized annular plasma

    Institute of Scientific and Technical Information of China (English)

    Li Wei; Gong Ma-Li; Wei Yan-Yu; Xie Hong-Quan

    2004-01-01

    @@ Propagation properties of electromagnetic waves in a dielectric-rod waveguide immersed in a magnetized annular plasma are presented in this paper. The dispersion relations are derived and calculated. The results show that the dielectric-rod loading can make the structure less dispersive and the transmission frequency-band broadened.

  17. Experimental characterization of dielectric-loaded plasmonic waveguide-racetrack resonators at near-infrared wavelengths

    DEFF Research Database (Denmark)

    Garcia, Cesar; Coello, Victor; Han, Zhanghua

    2012-01-01

    Dielectric-loaded plasmonic waveguide-racetrack resonators (WRTRs) were designed and fabricated for operating at near-infrared wavelengths (750–850 nm) and characterized using leakage-radiation microscopy. The transmission spectra of the WRTRs are found experimentally and compared to the calculat...

  18. Sevick's transmission line transformers theory and practice

    CERN Document Server

    Mack, Raymond

    2014-01-01

    An updated and reorganized revision of the classic book Transmission Line Transformers (2001) by Jerry Sevick, this book provides communication engineers with a clear technical presentation of both the theory and practical applications of the transmission of radio communication.

  19. Mycobacterial factors relevant for transmission of tuberculosis

    NARCIS (Netherlands)

    Verhagen, L.M.; Hof, S. van den; Deutekom, H. van; Hermans, P.W.M.; Kremer, K.; Borgdorff, M.W.; Soolingen, D. van

    2011-01-01

    BACKGROUND: Tuberculosis (TB) transmission is associated with patient-related risk factors. However, DNA fingerprint analysis has provided anecdotal evidence suggesting a role for bacteriological factors. METHODS: To examine the importance of the bacteriological component in TB transmission, we inve

  20. Internet Load and Traffic Balancing

    Institute of Scientific and Technical Information of China (English)

    李文正; 郭巧; 郭为民

    2005-01-01

    Load and traffic balancing for the Internet are analyzed. An intelligent domain name system(DNS) policy for the control and management of content distribution networks (CDN) is presented. An CDNs network based Urtitech IntelliDNS is built, and performance of the network in realizing traffic and load balancing is measured. It is proved that CDNs provide a valuable service and the methods are feasible.

  1. Wind Structure and Wind Loading

    DEFF Research Database (Denmark)

    Brorsen, Michael

    The purpose of this note is to provide a short description of wind, i.e. of the flow in the atmosphere of the Earth and the loading caused by wind on structures. The description comprises: causes to the generation of windhe interaction between wind and the surface of the Earthhe stochastic nature...... of windhe interaction between wind and structures, where it is shown that wind loading depends strongly on this interaction...

  2. Acoustic impedances of audiometric earphones coupled to different loads

    DEFF Research Database (Denmark)

    Ciric, Dejan; Hammershøi, Dorte

    2005-01-01

    The acoustic impedance of an audiometric earphone is one of the factors that can affect sound transmission through the ear during tests of hearing sensitivity. Similar situation exists during calibration of the earphone where its impedance can affect sound transmission through a coupler...... impedances is applied, which is based on the transfer function between two microphone locations in an impedance tube. For that purpose, the special measuring tube containing four microphones is developed, where different pairs of microphones are used for different frequency ranges. During the measurements......, audiometric earphones are coupled to different loads. Thus, they are placed on different terminations of the tube including metal plate, artificial rubber pinna and upper part of the standardized coupler. The results show that the impedances of earphones are different, but they also differ from radiation...

  3. INFINITELY VARIABLE TRANSMISSION USING FOUR BAR MECHANISM

    OpenAIRE

    Dr.N. ARUNKUMAR; Santhosh, R.; S. SUNIL SUBRAMANIAM

    2014-01-01

    Most of the continuously variable transmission systems in automobiles now-a-days are non-positive drives. This means that they cannot be used in heavy vehicles that require very high torque to be transmitted. This new type of infinitely variable transmission is aimed at transmitting high torques by making it a positive drive, thus making continuously variable transmission systems to be suitable for heavy vehicles. Infinitely variable transmission system and continuously variable transmissi...

  4. Assessing transmissibility of HIV-1 drug resistance mutations from treated and from drug-naive individuals

    Science.gov (United States)

    Winand, Raf; Theys, Kristof; Eusébio, Mónica; Aerts, Jan; Camacho, Ricardo J.; Gomes, Perpetua; Suchard, Marc A.; Vandamme, Anne-Mieke; Abecasis, Ana B.

    2015-01-01

    Objectives: Surveillance drug resistance mutations (SDRMs) in drug-naive patients are typically used to survey HIV-1-transmitted drug resistance (TDR). We test here how SDRMs in patients failing treatment, the original source of TDR, contribute to assessing TDR, transmissibility and transmission source of SDRMs. Design: This is a retrospective observational study analyzing a Portuguese cohort of HIV-1-infected patients. Methods: The prevalence of SDRMs to protease inhibitors, nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) in drug-naive and treatment-failing patients was measured for 3554 HIV-1 subtype B patients. Transmission ratio (prevalence in drug-naive/prevalence in treatment-failing patients), average viral load and robust linear regression with outlier detection (prevalence in drug-naive versus in treatment-failing patients) were analyzed and used to interpret transmissibility. Results: Prevalence of SDRMs in drug-naive and treatment-failing patients were linearly correlated, but some SDRMs were classified as outliers – above (PRO: D30N, N88D/S, L90 M, RT: G190A/S/E) or below (RT: M184I/V) expectations. The normalized regression slope was 0.073 for protease inhibitors, 0.084 for NRTIs and 0.116 for NNRTIs. Differences between SDRMs transmission ratios were not associated with differences in viral loads. Conclusion: The significant linear correlation between prevalence of SDRMs in drug-naive and in treatment-failing patients indicates that the prevalence in treatment-failing patients can be useful to predict levels of TDR. The slope is a cohort-dependent estimate of rate of TDR per drug class and outlier detection reveals comparative persistence of SDRMs. Outlier SDRMs with higher transmissibility are more persistent and more likely to have been acquired from drug-naive patients. Those with lower transmissibility have faster reversion dynamics after transmission and are associated with

  5. Environmental Aspects of Load Management

    Energy Technology Data Exchange (ETDEWEB)

    Abaravicius, Juozas

    2004-02-01

    This study approaches load management from an environmental perspective. It identifies and discusses the possible environmental benefits of load management and evaluates their significance, primary focusing on CO{sub 2} emissions reduction. The analysis is carried out on two levels: national - the Swedish electricity market, and local - one electric utility in southern Sweden. Our results show the importance of considering the influence of site-specific or level-specific conditions on the environmental effects of load management. On the national level, load management measures can hardly provide significant environmental benefits, due to the high hydropower production in Sweden, which is the demand following production source. Emission reductions will rather be the result of energy efficiency measures, which will cut the load demand as well as the energy demand. However, when it comes to a local (utility) level, where load management is considered as an alternative to an installation of peak diesel power plant, the benefits are clear. It is demonstrated that significant CO{sub 2} emissions savings can be achieved due to avoided peak diesel power production.

  6. Exploration of Resource and Transmission Expansion Decisions in the Western Renewable Energy Zone Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Andrew D.; Phadke, Amol A.; Wiser, Ryan H.

    2010-06-10

    The Western Renewable Energy Zone (WREZ) initiative brings together a diverse set of voices to develop data, tools, and a unique forum for coordinating transmission expansion in the Western Interconnection. In this paper we use a new tool developed in the WREZ initiative to evaluate possible renewable resource selection and transmission expansion decisions. We evaluate these decisions under a number of alternative future scenarios centered on meeting 33percent of the annual load in the Western Interconnection with new renewable resources located within WREZ-identified resource hubs. Our analysis finds that wind energy is the largest source of renewable energy procured to meet the 33percent RE target across nearly all scenarios analyzed (38-65percent). Solar energy is almost always the second largest source (14-41percent). We find several load zones where wind energy is the least cost resource under a wide range of sensitivity scenarios. Load zones in the Southwest, on the other hand, are found to switch between wind and solar, and therefore to vary transmission expansion decisions, depending on uncertainties and policies that affect the relative economics of each renewable option. Further, we find that even with total transmission expenditures of $17-34 billion these costs still represent just 10-19percent of the total delivered cost of renewable energy.

  7. Exploring Relay Cooperation for Secure and Reliable Transmission in Two-HopWireless Networks

    Directory of Open Access Journals (Sweden)

    Yulong Shen

    2014-03-01

    Full Text Available This work considers the problem of secure and reliable information transmission via relay cooperation in two-hop relay wireless networks without the information of both eavesdropper channels and locations. While previous work on this problem mainly studied infinite networks and their asymptotic behavior and scaling law results, this papers focuses on a more practical network with finite number of system nodes and explores the corresponding exact result on the number of eavesdroppers one network can tolerate to ensure desired secrecy and reliability. We first study the scenario where path-loss is equal between all pairs of nodes and consider two transmission protocols there, one adopts an optimal but complex relay selection process with less load balance capacity while the other adopts a random but simple relay selection process with good load balance capacity. Theoretical analysis and numerical results are then provided to determine the maximum number of eavesdroppers one network can tolerate to ensure a desired performance in terms of the secrecy outage probability and transmission outage probability. We further extend our study to the more general scenario where path-loss between each pair of nodes also depends on the distance between them, for which a new transmission protocol with both preferable relay selection and good load balance as well as the corresponding theoretical analysis and numerical results are presented.

  8. 46 CFR 169.689 - Demand loads.

    Science.gov (United States)

    2010-10-01

    ... Electrical Electrical Installations on Vessels of 100 Gross Tons and Over § 169.689 Demand loads. Demand loads must meet § 111.60-7 of this chapter except that smaller demand loads for motor feeders...

  9. Malaria transmission rates estimated from serological data.

    OpenAIRE

    Burattini, M. N.; Massad, E; Coutinho, F. A.

    1993-01-01

    A mathematical model was used to estimate malaria transmission rates based on serological data. The model is minimally stochastic and assumes an age-dependent force of infection for malaria. The transmission rates estimated were applied to a simple compartmental model in order to mimic the malaria transmission. The model has shown a good retrieving capacity for serological and parasite prevalence data.

  10. 40 CFR 86.528-78 - Transmissions.

    Science.gov (United States)

    2010-07-01

    ... be conducted with automatic transmissions in “Drive” (highest gear). Automatic clutch-torque... shall be in gear with the clutch disengaged; except first idle, see §§ 86.536 and 86.537. (d) The... transmissions shall shift automatically through the normal sequence of gears; manual transmissions shall...

  11. Average Transmission Probability of a Random Stack

    Science.gov (United States)

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  12. Fractional Frequency Transmission System and Its Applications

    Institute of Scientific and Technical Information of China (English)

    WANG Xifan; WANG Xiuli; TENG Yufei

    2012-01-01

    In 1994, we proposed transmission approach, the a novel fractional electricity frequency transmission system (FFTS), which uses lower frequency (50/3 Hz) to reduce the electrical length of AC power lines and thus obviously increases transmission capacity. The system is especially suitable to transmit remote renewable power such as hydro power and wind power.

  13. Advanced Power Transmission of the Future

    OpenAIRE

    Rabinowitz, Mario

    2003-01-01

    Electric power is a vital ingredient of modern society. This article is written to provide an insight into the physics and engineering that go into the transmission of electric power and its potential modernization. Topics covered will be Transmission and Distribution, Comparing Overhead and Underground Delivery, Pros and Cons of Underground Delivery, Superconducting Transmission, Cryorisistive Delivery, Hyperconductivity, and Metal-Plated Graphite Fibers.

  14. Average Transmission Probability of a Random Stack

    Science.gov (United States)

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  15. Mounting of reference surface for a transmission sphere

    Science.gov (United States)

    Peng, Wei-Jei; Ho, Cheng-Fang; Yu, Zong-Ru; Huang, Chien-Yao; Kuo, Ching-Hsiang; Hsu, Wei-Yao

    2016-09-01

    The mounting design of a reference surface for a 6-in transmission sphere is presented in this paper. To achieve highprecision measurement in interferometry, the reference wavefront error should be controlled within peak-to-valley (PV) 0.1 λ (λ=0.6328 um) for subtraction in calibration. The reference wavefront error includes the system aberration error and the irregularity of the reference surface. When a transmission sphere is well aligned, the reference wavefront error is dominated by the reference surface. The mounting of the reference surface is imperative because the surface deformation of the reference surface after mounting needs to be lower than 0.1 λ. Besides the mounting deformation, self-weight deformation is also considerable for large optics, such as 6-in reference surface in our study. Consequently, a semikinematic mounting is applied using three small contact areas to avoid over constraint. The transmission sphere in our study is vertically tested on QED aspheric stitching interferometer (ASI), and then the trefoil aberration is occurred. There are two methods to decrease surface deformation after mounting, including deformation correction using computer control optical surfacing (CCOS) and adding soft supporting between hard mounting. In this study, three soft supports are used to share the loads of three rigid supports and then to minimize surface deformation due to gravity. Mounting design and experiments are described in this paper. Finally, the reference wavefront error of the prototype is successfully restrained within 0.1 λ in measurement.

  16. Verification of long-term load measurement technique

    DEFF Research Database (Denmark)

    Schmidt Paulsen, Uwe

    The present report is the final effort of tasks carried out under UPWIND WP1B2 transmission and conversion, which describes: 1) results and recommendations developed in the course of developing the long-term load measurement technique 2) the hardware details, type of sensors and location, data...... storage and 3) data analysis technique to verify design load assumptions. The work is carried out under Contract no 019945 (SES6) "UPWIND" within the European Commission The interaction between the mechanical and electrical generator subsystems is described rudimentarily, based primarily on HAWC2...... simulations below stall of the mechanical system with simple generator and gearbox systems. The electrical system simulations were not carried out as intended in DOW[2], but indications of the conditions for establishing the interaction have been described by measurements and by argument, that this might have...

  17. Load Reduction of Wind Turbines Using Receding Horizon Control

    DEFF Research Database (Denmark)

    Soltani, Mohsen; Wisniewski, Rafal; Brath, Per

    2011-01-01

    Large scale wind turbines are lightly damped mechanical structures driven by wind that is constantly fluctuating. In this paper, we address the design of a model-based receding horizon control scheme to reduce the structural loads in the transmission system and the tower, as well as provide...... constant (or at least smooth) power generation. Our controller incorporates two optimization problems: one to predict or estimate mean wind speed, given LIDAR data, and the other to carry out receding horizon control to choose the control inputs. The method is verified against an existing wind turbine...... control system, and shows reductions in both extreme loads and power fluctuations by 80% and 90% respectively when compared to a conventional controller....

  18. Centrifuge modelling of the pushover failure of an electricity transmission tower

    Energy Technology Data Exchange (ETDEWEB)

    Richards, D.J. [Southampton Univ. (United Kingdom). School of Civil Engineering and the Environment; White, D.J. [Western Australia Univ., Crawley, WA (Australia). Centre for Offshore Foundation Systems, Faculty of Engineering, Computing and Mathematics

    2010-04-15

    The foundation systems of broad-based lattice power transmission towers must be designed to resist uplift, lateral and downward forces arising from the tower's weight, and tension within the conductor wires and wind loadings. This study investigated foundation failure mechanisms during the rapid horizontal pushover of a power transmission tower. The centrifuge model tests were designed to simulate a wind gust loading or broken transmission line response. The tower was supported on 4 pad foundations set in clay and backfilled with sand. The loads at each foundation were measured during fast and flow pushover. The influence of tensile resistance mobilized at the underside of the footings was investigated. The measured performance of the tower footings showed good agreement with results obtained from a series of tests conducted to measure a single footing subjected to vertical loading. Tower response was back-analyzed as a simple push-pull model. The calculated uplift capacity of the footing backfill showed good agreement with the observed response of tower footings subjected to slow pushover. The additional capacity mobilized during fast pushover was caused by tensile resistance created by the reverse bearing capacity beneath the base of the footings. 30 refs., 3 tabs., 11 figs.

  19. Analysis of source-grid-load contribution to wind power accommodation

    Science.gov (United States)

    Li, Nan; Zhang, Jinfang; Zhang, Fuqiang

    2017-01-01

    In recent years, China’s wind power is developing rapidly, but wind electricity curtailment becomes a serious problem. This paper evaluates wind power penetration limit from peak regulation, analyses relevant technical elements that impact wind power accommodation, coving the source side, the transmission side and the load side. By taking certain measures around the three aspects, for example, reducing the minimum technical output of conventional units, increasing outbound transmission capacity, or increasing the valley load, wind electricity curtailment will be effectively reduced. This paper quantitatively analyses wind power penetration limit under certain conditions and the source-grid-load contribution to wind power accommodation, and explores the important technical factors that affect wind power accommodation.

  20. [Structure of allostatic load in railway workers].

    Science.gov (United States)

    Gorokhova, S G; Pfaf, V F; Muraseyeva, E V; Akhsanova, E R; Prigorovskaya, T S; At'kov, O Yu

    2016-01-01

    The authors studied allostatic load in railway workers, as an indicator of stress effect. Analysis covered biomarkers that form allostatic load index, and their ratio for variable allostatic load index levels. Moderate allostatic load appeared to prevail in the examinees group. Findings are that systolic and diastolic blood pressure, general cholesterol and hemoglobin make major contribution into allostatic load index. Comparison covered models of allostatic load index calculation for variable biomarkers sets.

  1. Calibration set up for load cells

    Science.gov (United States)

    Rao, T. V. Govinda; Venkatesh, C. S.; Shivashankar, N.

    1989-05-01

    The planning, designing, fabrication, and calibration of 30, 50, and 100 ton tension load cells and 30 ton shear load cells are described. The tension load cells are for monitoring the force developed by earth moving vehicles and the shear load cells are for monitoring the load that tipplers unload form platform to ground. The shear load cells were incorporated into a rotary wagon tippler.

  2. Transmission paths information systems under open access. Developments in the USA; Lastflussinformationssysteme fuer den Wettbewerb. Entwicklungen in den USA

    Energy Technology Data Exchange (ETDEWEB)

    Florek, S. [Tennessee Valley Authority, Transmission/Power Supply, Chattanooga, TN (United States)

    1998-09-01

    Open access to transmission networks is a prerequisite of electricity trading in the deregulated power market. Another basic requirement for market efficiency is reliable transmission grid operation as well as transparency of operations for all parties involved. Therefore, transmission paths information systems are needed for ensuring reliable transfer operations. In the USA, the Transmission Interchange System (TIS) became operational in July 1997 as a load management system, which stores transmission operations for the various traders under open access by so-called transmission tags. Another feature for system monitoring is transmission security regions, within which security coordinators ensure reliable system operation. The security coordinators have access to all transmission paths information within the interconnected systems and thus are able to initiate load management measures for prevention of transfer bottlenecks or failures. The accompanying agreement defining responsibilities of network owners and users as well as operations pricing forms the legal basis of electricity trading in the deregulated market. (orig./CB) [Deutsch] Freier Zugang zum Uebertragungsnetz ist die Grundlage fuer einen funktionierenden Wettbewerb im Elektrizitaetshandel. Daher muss fuer einen effizienten Markt ein sicherer und zuverlaessiger Netzbetrieb gewaehrleistet sein. Dies ist nur moeglich, wenn jeder Netzbetreiber einen vollstaendigen Ueberblick ueber alle Uebertragungen erhaelt, die ueber sein Uebertragungsnetz abgewickelt werden. Lastflussinformationssysteme sind fuer einen sicheren Netzbetrieb unverzichtbar. Im Juli 1997 wurde das Transmission Interchange System (TIS) in den USA in Betrieb genommen und die Erfassung aller Uebertragungen im Hochspannungsnetz durch sogenannte Transmission Tags eingefuehrt. Zur Ueberwachung des Netzbetriebs wurden Transmission Security-Regionen definiert. Innerhalb dieser Regionen sind Security Coordinators fuer den sicheren Netzbetrieb

  3. Feedback Control of Transmission Line by Static VAR Compensators (TSC & TCR Using Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Arushi Jaiswal

    2013-07-01

    Full Text Available Voltage profile maintenance of a transmission system can be done by using feedback control methodology and the compensation technique used is Static VAR compensation. This thesis describes a MATLAB based SIMULINK model that can be implemented in real time systems to maintain a constant voltage profile during load changes and fault conditions. In any power system the basic requirement is to keep the voltage of the system constant so that the load functions properly. Whenever there is a fault or any load is disconnected, the active and reactive power requirements of the system changes. As a result, the voltage of the system changes. Therefore to maintain a constant voltage profile shunt compensators are used near the load end, in the model presented in this project. Fuzzy logic is also implemented to set the proper compensation required

  4. Sexual transmission of human T-cell lymphotropic virus type 1

    Directory of Open Access Journals (Sweden)

    Arthur Paiva

    2014-06-01

    Full Text Available Human T-cell lymphotropic virus type 1 (HTLV-1 is endemic in many parts of the world and is primarily transmitted through sexual intercourse or from mother to child. Sexual transmission occurs more efficiently from men to women than women to men and might be enhanced by sexually transmitted diseases that cause ulcers and result in mucosal ruptures, such as syphilis, herpes simplex type 2 (HSV-2, and chancroid. Other sexually transmitted diseases might result in the recruitment of inflammatory cells and could increase the risk of HTLV-1 acquisition and transmission. Additionally, factors that are associated with higher transmission risks include the presence of antibodies against the viral oncoprotein Tax (anti-Tax, a higher proviral load in peripheral blood lymphocytes, and increased cervicovaginal or seminal secretions. Seminal fluid has been reported to increase HTLV replication and transmission, whereas male circumcision and neutralizing antibodies might have a protective effect. Recently, free virions were discovered in plasma, which reveals a possible new mode of HTLV replication. It is unclear how this discovery might affect the routes of HTLV transmission, particularly sexual transmission, because HTLV transmission rates are significantly higher from men to women than women to men.

  5. Design of Chebychev’s Low Pass Filters Using Nonuniform Transmission Lines

    Directory of Open Access Journals (Sweden)

    Said Attamimi

    2016-03-01

    Full Text Available Transmission lines are utilized in many applications to convey energy as well as information. Nonuniform transmission lines (NTLs are obtained through variation of the characteristic quantities along the axial direction. Such NTLs can be used to design network elements, like matching circuits, delay equalizers, filters, VLSI interconnections, etc. In this work, NTLs were analyzed with a numerical method based on the implementation of method of moment. In order to approximate the voltage and current distribution along the transmission line, a sum of basis functions with unknown amplitudes was introduced. As basis function, a constant function was used. In this work, we observed several cases such as lossless and lossy uniform transmission lines with matching and arbitrary load. These cases verified the algorithm developed in this work. The second example consists of nonuniform transmission lines in the form of abruptly changing transmission lines. This structure was used to design a Chebychev’s low pass filter. The calculated reflection and transmission factors of the filters showed some coincidences with the measurements.

  6. Transmission system planning in Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Barrie, D.; Macedo, F.X.; Mcconnach, J.S. [Ontario Hydro, Toronto, ON (Canada)

    1994-12-31

    In recent years, new and modified approaches to planning the large transmission system that serves the province of Ontario, Canada, have been necessary to accommodate the rapidly changing planning environment including slower uncertain growth, ageing of facilities, integration of demand side management and non utility generation options, increased competitiveness, increased financial stresses and affordable constraints. This paper describes some of the new and modified approaches and tools that have been adopted or are being developed by Ontario Hydro to cope with this changing environment. (author) 9 refs., 4 figs.

  7. Neutron Transmission through Sapphire Crystals

    DEFF Research Database (Denmark)

    Sapphire crystals are excellent filters of fast neutrons, while at the same time exhibit moderate to very little absorption at smaller energies. We have performed an extensive series of measurements in order to quantify the above effect. Alongside our experiments, we have performed a series...... of simulations, in order to reproduce the transmission of cold neutrons through sapphire crystals. Those simulations were part of the effort of validating and improving the newly developed interface between the Monte-Carlo neutron transport code MCNP and the Monte Carlo ray-tracing code McStas....

  8. Corrosive effects of hvdc transmission

    Energy Technology Data Exchange (ETDEWEB)

    Cornwell, F.E.; Backstrom, T.E.

    1966-02-01

    Field tests using ac transmission lines for introduction of direct current into the earth at widely separated points are described. One test circuit was between a Tracy pumping plant and a Shasta power plant in California, and two others were in the Hoover power plant area. Evaluation of the effects of such ground currents on corrosion of buried metalwork was a primary aim of the tests. Potential gradients, pipe-to-soil potentials, and soil resistivities are discussed in detail. Estimates are made of the distances from ehv dc terminal installations within which corrosion prevention procedures may become necessary.

  9. Force transmission in epithelial tissues.

    Science.gov (United States)

    Vasquez, Claudia G; Martin, Adam C

    2016-03-01

    In epithelial tissues, cells constantly generate and transmit forces between each other. Forces generated by the actomyosin cytoskeleton regulate tissue shape and structure and also provide signals that influence cells' decisions to divide, die, or differentiate. Forces are transmitted across epithelia because cells are mechanically linked through junctional complexes, and forces can propagate through the cell cytoplasm. Here, we review some of the molecular mechanisms responsible for force generation, with a specific focus on the actomyosin cortex and adherens junctions. We then discuss evidence for how these mechanisms promote cell shape changes and force transmission in tissues.

  10. 75 FR 4375 - Transmission Loading Relief Reliability Standard and Curtailment Priorities

    Science.gov (United States)

    2010-01-27

    ... Procedures Section of this document. FOR FURTHER INFORMATION CONTACT: Ruta Kalvaitis Sku as, Federal Energy...-6647, ruta.skucas@ferc.gov . Thomas Dautel, Federal Energy Regulatory Commission, Office of...

  11. Effect of contact ratio on spur gear dynamic load

    Science.gov (United States)

    Liou, Chuen-Huei; Lin, Hsiang Hsi; Oswald, Fred B.; Townsend, Dennis P.

    A computer simulation is presented which shows how the gear contact ratio affects the dynamic load on a spur gear transmission. The contact ratio can be affected by the tooth addendum, the pressure angle, the tooth size (diametral pitch), and the center distance. The analysis presented was performed using the NASA gear dynamics code, DANST. In the analysis, the contact ratio was varied over the range 1.20 to 2.40 by changing the length of the tooth addendum. In order to simplify the analysis, other parameters related to contact ratio were held constant. The contact ratio was found to have a significant influence on gear dynamics. Over a wide range of operating speeds, a contact ratio close to 2.0 minimized dynamic load. For low contact ratio gears (contact ratio less than 2.0), increasing the contact ratio reduced the gear dynamic load. For high contact ratio gears (contact ratio = or greater than 2.0), the selection of contact ratio should take into consideration the intended operating speeds. In general, high contact ratio gears minimized dynamic load better than low contact ratio gears.

  12. The DEMO wall load challenge

    Science.gov (United States)

    Wenninger, R.; Albanese, R.; Ambrosino, R.; Arbeiter, F.; Aubert, J.; Bachmann, C.; Barbato, L.; Barrett, T.; Beckers, M.; Biel, W.; Boccaccini, L.; Carralero, D.; Coster, D.; Eich, T.; Fasoli, A.; Federici, G.; Firdaouss, M.; Graves, J.; Horacek, J.; Kovari, M.; Lanthaler, S.; Loschiavo, V.; Lowry, C.; Lux, H.; Maddaluno, G.; Maviglia, F.; Mitteau, R.; Neu, R.; Pfefferle, D.; Schmid, K.; Siccinio, M.; Sieglin, B.; Silva, C.; Snicker, A.; Subba, F.; Varje, J.; Zohm, H.

    2017-04-01

    For several reasons the challenge to keep the loads to the first wall within engineering limits is substantially higher in DEMO compared to ITER. Therefore the pre-conceptual design development for DEMO that is currently ongoing in Europe needs to be based on load estimates that are derived employing the most recent plasma edge physics knowledge. An initial assessment of the static wall heat load limit in DEMO infers that the steady state peak heat flux limit on the majority of the DEMO first wall should not be assumed to be higher than 1.0 MW m-2. This compares to an average wall heat load of 0.29 MW m-2 for the design {\\tt {EU}}{\\tt {~}}{\\tt {DEMO1}}{\\tt {~2015}} assuming a perfect homogeneous distribution. The main part of this publication concentrates on the development of first DEMO estimates for charged particle, radiation, fast particle (all static) and disruption heat loads. Employing an initial engineering wall design with clear optimization potential in combination with parameters for the flat-top phase (x-point configuration), loads up to 7 MW m-2 (penalty factor for tolerances etc not applied) have been calculated. Assuming a fraction of power radiated from the x-point region between 1/5 and 1/3, peaks of the total power flux density due to radiation of 0.6-0.8 MW m-2 are found in the outer baffle region. This first review of wall loads, and the associated limits in DEMO clearly underlines a significant challenge that necessitates substantial engineering efforts as well as a considerable consolidation of the associated physics basis.

  13. Mother-to-Child Transmission of HTLV-1 Epidemiological Aspects, Mechanisms and Determinants of Mother-to-Child Transmission

    Directory of Open Access Journals (Sweden)

    Florent Percher

    2016-02-01

    Full Text Available Human T-cell Lymphotropic Virus type 1 (HTLV-1 is a human retrovirus that infects at least 5–10 million people worldwide, and is the etiological agent of a lymphoproliferative malignancy; Adult T-cell Leukemia/Lymphoma (ATLL; and a chronic neuromyelopathy, HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP, as well as other inflammatory diseases such as infective dermatitis and uveitis. Besides sexual intercourse and intravenous transmission, HTLV-1 can also be transmitted from infected mother to child during prolonged breastfeeding. Some characteristics that are linked to mother-to-child transmission (MTCT of HTLV-1, such as the role of proviral load, antibody titer of the infected mother, and duration of breastfeeding, have been elucidated; however, most of the mechanisms underlying HTLV-1 transmission during breast feeding remain largely unknown, such as the sites of infection and cellular targets as well as the role of milk factors. The present review focuses on the latest findings and current opinions and perspectives on MTCT of HTLV-1.

  14. Exploration of Resource and Transmission Expansion Decisions in the Western Renewable Energy Zone Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Andrew; Phadke, Amol; Wiser, Ryan

    2010-02-16

    Building transmission to reach renewable energy (RE) goals requires coordination among renewable developers, utilities and transmission owners, resource and transmission planners, state and federal regulators, and environmental organizations. The Western Renewable Energy Zone (WREZ) initiative brings together a diverse set of voices to develop data, tools, and a unique forum for coordinating transmission expansion in the Western Interconnection. In this report we use a new tool developed in the WREZ initiative to evaluate possible renewable resource selection and transmission expansion decisions. We evaluate these decisions under a number of alternative future scenarios centered on meeting 33% of the annual load in the Western Interconnection with new renewable resources located within WREZ-identified resource hubs. Of the renewable resources in WREZ resource hubs, and under the assumptions described in this report, our analysis finds that wind energy is the largest source of renewable energy procured to meet the 33% RE target across nearly all scenarios analyzed (38-65%). Solar energy is almost always the second largest source (14-41%). Solar exceeds wind by a small margin only when solar thermal energy is assumed to experience cost reductions relative to all other technologies. Biomass, geothermal, and hydropower are found to represent a smaller portion of the selected resources, largely due to the limited resource quantity of these resources identified within the WREZ-identified hubs (16-23% combined). We find several load zones where wind energy is the least cost resource under a wide range of sensitivity scenarios. Load zones in the Southwest, on the other hand, are found to switch between wind and solar, and therefore to vary transmission expansion decisions, depending on uncertainties and policies that affect the relative economics of each renewable option. Uncertainties and policies that impact bus-bar costs are the most important to evaluate carefully, but

  15. 49 CFR 191.13 - Distribution systems reporting transmission pipelines; transmission or gathering systems...

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Distribution systems reporting transmission pipelines; transmission or gathering systems reporting distribution pipelines. 191.13 Section 191.13... Distribution systems reporting transmission pipelines; transmission or gathering systems reporting...

  16. 49 CFR 571.102 - Standard No. 102; Transmission shift position sequence, starter interlock, and transmission...

    Science.gov (United States)

    2010-10-01

    ... position. S3.1.2Transmission braking effect. In vehicles having more than one forward transmission gear... when the transmission shift position is in any forward drive gear; (b) The engine may not automatically stop when the transmission is in reverse gear; and (c) The engine may automatically restart in...

  17. Magnetic Force Transmission of a Reciprocating Motion

    Institute of Scientific and Technical Information of China (English)

    Qing-chang Tan; Fu-sheng Zheng; Jian-gang Li

    2008-01-01

    Magnetic force transmission of a reciprocating motion is studied by theoretical analysis and experiment. A mathematical model for calculating the magnetic force is derived using the theory of equivalent magnetic charges. An experimental rig is constructed to test the transmission and the model is verified by experiment. Effect of the transmission parameters on the magnetic force is analyzed theoretically from the model, and characteristic of the transmission is studied experimentally. Since the transmission is without direct contact between two elements, it is suitable for application in an organism.

  18. Face-gear drives: Design, analysis, and testing for helicopter transmission applications

    Science.gov (United States)

    Litvin, F. L.; Wang, J.-C.; Bossler, R. B., Jr.; Chen, Y.-J. D.; Heath, G.; Lewicki, D. G.

    1992-10-01

    The use of face-gears in helicopter transmissions was explored. A light-weight, split-torque transmission design utilizing face-gears is described. Face-gear design and geometry were investigated. Topics included tooth generation, limiting inner and outer radii, tooth contact analysis, contact ratio, gear eccentricity, grinding, and structural stiffness. Design charts were developed to determine minimum and maximum face-gear inner and outer radii. An analytical study showed that the face-gear drive is relatively insensitive to gear misalignment with respect to transmission errors, but the tooth contact is affected by misalignment. A method of localizing the bearing contact to permit operation with misalignment was explored. Two new methods for grinding of the face-gear tooth surfaces were also investigated. The proper choice of shaft stiffness enabled good load sharing in the split-torque transmission design. Face-gear experimental studies were also conducted. These tests demonstrated the feasibility of face-gears in high-speed, high-load applications such as helicopter transmissions.

  19. Face-gear drives: Design, analysis, and testing for helicopter transmission applications

    Science.gov (United States)

    Litvin, F. L.; Wang, J.-C.; Bossler, R. B., Jr.; Chen, Y.-J. D.; Heath, G.; Lewicki, D. G.

    1992-01-01

    The use of face-gears in helicopter transmissions was explored. A light-weight, split-torque transmission design utilizing face-gears is described. Face-gear design and geometry were investigated. Topics included tooth generation, limiting inner and outer radii, tooth contact analysis, contact ratio, gear eccentricity, grinding, and structural stiffness. Design charts were developed to determine minimum and maximum face-gear inner and outer radii. An analytical study showed that the face-gear drive is relatively insensitive to gear misalignment with respect to transmission errors, but the tooth contact is affected by misalignment. A method of localizing the bearing contact to permit operation with misalignment was explored. Two new methods for grinding of the face-gear tooth surfaces were also investigated. The proper choice of shaft stiffness enabled good load sharing in the split-torque transmission design. Face-gear experimental studies were also conducted. These tests demonstrated the feasibility of face-gears in high-speed, high-load applications such as helicopter transmissions.

  20. Open Access Transmission and Renewable Energy Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Porter, K.

    1996-09-01

    In April 1996, the Federal Regulatory Commission (PERC) approved Orders 888 and 889 and released a draft rule for public comment on capacity reservation tariffs (CRTs). Order No. 888 requires electric utilities to file transmission tariffs that would allow transmission access to third parties who want to conduct wholesale transactions, and Order No. 889 requires transmission-owning utilities to set up open access, same-time information systems (OASIS), using commercial software and Internet protocols. This paper discusses these Orders in detail, as well as some of the issues before FERC with implications for renewables, which include: transmission pricing; transmission terms and conditions; reassignment of transmission capacity; defining state and FERC jurisdiction over transmission and distribution; the pricing of ancillary services; and the adoption and implementation of independent system operators.