WorldWideScience

Sample records for kv overhead transmission

  1. Study of a phase-to-ground fault on a 400 kV overhead transmission line

    Science.gov (United States)

    Iagăr, A.; Popa, G. N.; Diniş, C. M.

    2018-01-01

    Power utilities need to supply their consumers at high power quality level. Because the faults that occur on High-Voltage and Extra-High-Voltage transmission lines can cause serious damages in underlying transmission and distribution systems, it is important to examine each fault in detail. In this work we studied a phase-to-ground fault (on phase 1) of 400 kV overhead transmission line Mintia-Arad. Indactic® 650 fault analyzing system was used to record the history of the fault. Signals (analog and digital) recorded by Indactic® 650 were visualized and analyzed by Focus program. Summary of fault report allowed evaluation of behavior of control and protection equipment and determination of cause and location of the fault.

  2. Towers of the new 380 kV high-voltage overhead line across the Elbe

    Energy Technology Data Exchange (ETDEWEB)

    Kiessling, F; Sperl, H D; Wagemann, F

    1979-11-01

    As part of the European power transmission line between North Sweden and Southern Italy, a 380 kV rotary-current overhead line crosses the Elbe river south of Hamburg. To achieve the overhead clearance of 80 m required for navigation and the maximum line sag of 85 m, two steel trelliswork towers were constructed about 1200 m apart, each of them 227 m high. The 12 phases (cables) of the line are suspended each on three horizontal beams at a horizontal distance of 16 m. Exceptional loads far beyond the standards set in VDE 0210/5.69 have been assumed for the layout. In the case of the wind loads the frequent gales had to be considered; for ice loads, class I of the IEC/TC 11 Draft on Ice loading on Overhead Lines . Amsterdam 1977, was assumed. Some further loads are described as well as the tender procedure, supply and assembly of the towers.

  3. Underground cables as an alternative to overhead lines. A comparison of economic and technical aspects of voltages over 22 kV

    Energy Technology Data Exchange (ETDEWEB)

    Trohjell, J.E.; Vognild, I.H.

    1994-07-11

    The report presents technical and economical aspects of underground cables compared to overhead lines in Norway in high voltage transmission systems above 22 kV. The economical comparison between the two options includes capital costs of installation (investment costs), maintenance costs and costs of electrical losses. The main technical issues discussed are reliability and flexibility. 35 refs., 23 figs., 29 tabs.

  4. Big George to Carter Mountain 115-kV transmission line project, Park and Hot Springs Counties, Wyoming. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The Western Area Power Administration (Western) is proposing to rebuild, operate, and maintain a 115-kilovolt (kV) transmission line between the Big George and Carter Mountain Substations in northwest Wyoming (Park and Hot Springs Counties). This environmental assessment (EA) was prepared in compliance with the National Environmental Policy Act (NEPA) and the regulations of the Council on Environmental Quality (CEQ) and the Department of Energy (DOE). The existing Big George to Carter Mountain 69-kV transmission line was constructed in 1941 by the US Department of Interior, Bureau of Reclamation, with 1/0 copper conductor on wood-pole H-frame structures without an overhead ground wire. The line should be replaced because of the deteriorated condition of the wood-pole H-frame structures. Because the line lacks an overhead ground wire, it is subject to numerous outages caused by lightning. The line will be 54 years old in 1995, which is the target date for line replacement. The normal service life of a wood-pole line is 45 years. Under the No Action Alternative, no new transmission lines would be built in the project area. The existing 69-kV transmission line would continue to operate with routine maintenance, with no provisions made for replacement.

  5. Reduction of the visual impact of overhead transmission line systems through utilisation of line surge arresters as lightning protection

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard; Holbøll, Joachim

    2008-01-01

    with the Technical University of Denmark, on how to lessen the visual impact of 400 kV overhead line transmission systems. In this paper omission of shield wires combined with installation of a suitable number of line surge arresters is investigated as a possible alternative to transmission lines equipped...... with shielding wires thereby reducing tower height, allowing more compact designs of towers thus minimizing the visual environment impact of the lines. Omission of shield wires in the system and instead utilizing a larger number of surge arresters in the (upper) phases of an overhead line without reduction...... will be investigated by transient simulations on a 400 kV line with either shield wires or line surge arresters. These simulations will also be used to estimate number and location of the line surge arresters in the line to ensure a satisfactory performance of the line when omitting shield wires in the tower top...

  6. Residual life assessment of overhead transmission lines 110 kV and above and determination of their reconstruction terms

    Directory of Open Access Journals (Sweden)

    Uteuliyev Bauyrzhan

    2017-01-01

    Full Text Available In this article is given a method for assessment the residual life of overhead transmission lines on reinforced concrete supports with centrifuged poles. Reinforced concrete poles of supports, wires and lightning protection cables are adopted as the main elements. The intensity of change in the actual state parameters of these elements is determined by the laws of random variables distribution that allow predicting the residual life and the timing of repairs and reconstruction of overhead transmission lines. The parameters of natural climatic conditions and other external factors are considered by including of coefficients into the formula for changing the actual state parameters.

  7. Sidney-North Yuma 230-kV Transmission Line Project, Colorado and Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    1991-06-01

    This report describes the need for a 230-kV overhead transmission line to supply power from Sidney, Nebraska to eastern Colorado. The alternative scenario compared to construction of the line is No Action. Rejected alternatives include underground lines and different routing paths, with a possible extension to the Sterling area. Both scenarios are evaluated for environmental effects, cost, and consequences for the eastern Colorado region. The proposed route is determined to be the environmentally preferred choice. 120 refs., 6 figs., 13 tabs. (MHB)

  8. Technical and economic data for overhead lines in high-voltage a. c. and d. c. transmission

    Energy Technology Data Exchange (ETDEWEB)

    1977-11-01

    For the study of 'High-power electricity transmission and distribution in densely populated areas' technical and economic data were compiled for high-voltage alternating current and direct current transmission. A modification of the overhead lines for transmitting higher powers is possible as required by means of higher rated transmission voltages, larger conductor cross-sections and a larger number of circuits installed on each mast. For the use of larger partial conductor cross-sections and of bundle conductors with more than 4 partial conductors, and also to use voltages higher than 380 kV, development work is requisite from the points of view of construction, installation, insulators and fittings. Further possible developments result from the use of new materials such as plastic insulators which make possible the use of more versatile shapes for application in heavy pollution, particulary for direct current overhead lines. By using insulating crossarms the width of path can be considerably reduced. Economic efficiency investigations show even today higher cost for such techniques compared with lines of earlier construction.

  9. Composite Based EHV AC Overhead Transmission Lines

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard

    and analysed with regard to the possibilities, limitations and risks widespread application of composite materials on EHV AC overhead transmission lines may present. To form the basis for evaluation of the useability of composite materials, dierent overhead line projects aimed at reducing the environmental...

  10. Workers exposure to electric fields in 400 kV substations and overhead line works

    International Nuclear Information System (INIS)

    Elovaara, J.; Kuisti, H.; Korpinen, L.

    2010-01-01

    The maximum exposing electric field strength magnitude in the highly inhomogeneous 400 kV electric field under work conditions can reach the value of several tens of kV/m. In spite of this the average current density is, in Finland, always lower than 10 mA/m 2 . Furthermore, the total body currents or contact currents are in 400 kV works clearly less than the limit value proposed by the EU's draft for Directive. On the basis of the obtained results it can be concluded that from the limit value point of view it is not necessary to take further actions to reduce the exposure of the workers when they are working in 400 kV substations and on 400 kV overhead lines. However, because the transient peak values of the contact current can be painful and disturb work, it is advisable to develop a safe and reliable method to connect the worker and the work object in the common ground (equipotential bonding). (authors)

  11. Visual impact of overhead power transmission lines and dielectric and corona effects constraints on insulation coordination

    International Nuclear Information System (INIS)

    Deponti, F.; Fini, G.P.; Porrino, A.; Rosa, F.

    1992-06-01

    In assessing overhead power transmission line design and planning criteria for the optimization of visual impact, safety and the reduction of electro magnetic disturbance effects, this paper reviews the research findings of ENEL, the Italian Electricity Board. The on-going research activities involve theoretical calculations and laboratory performance tests to determine the best compact configurations for 380 kV lines. The parameters under examination include: insulator spacing, sizing and salt fog resistivity; allowable overvoltages; maximum line length; behaviour in lightning conditions; radio and acoustics disturbances

  12. HVDC transmission preferred to 750 kV ac

    Energy Technology Data Exchange (ETDEWEB)

    1965-06-25

    It is unlikely that there will be a need in Britain for ac transmission voltages above 400 kV. But with the growing load density in the large conurbations with no possibility of local generation, high voltage dc transmission is likely to be most useful. It was concluded that by 1971 the 400 kV supergrid would be nation-wide and 6,200 circuit miles should be in service. With the expansion to accommodate the large new generating stations, the 400 kV supergrid would become an extremely high power distribution network rather than a transmission system. A higher voltage for transmission is outside the rational limit of speculation for a country the size of Britain.

  13. Interlaboratory comparison of measuring results of magnetic field near 400 kV overhead power line

    Directory of Open Access Journals (Sweden)

    Grbić Maja

    2012-01-01

    Full Text Available The paper presents a comparison of measured results of magnetic field near 400 kV overhead power lines obtained by three laboratories. This interlaboratory comparison was performed to ensure confidence in the quality of the test results. The measured results were analyzed with standard methods, using En number, based on which the evaluation of the laboratories was performed.

  14. A study on the insulation coordination of 765 kV system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Boo; Shim, Eung Bo [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center; Lee, Yong Han; Youn, Jae Yeong; Hwang, Chi Woo; Jung, Dong Hak [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)

    1996-12-31

    Analysis of the power frequency temporary overvoltage. Analysis of switching surges - Fault imitation, closing and re closing, fault clearing. Analysis of lightning surges. Insulation design of 765 kV overhead transmission line. Insulation coordination of 765 kV gas insulated substation. Transient recovery voltage and high speed ground switch (author). 38 refs., 55 figs.

  15. Electrical transmission

    Energy Technology Data Exchange (ETDEWEB)

    Sayers, D P

    1960-05-01

    After briefly tracing the history of electricity transmission, trends in high voltage transmission and experiments being conducted on 650 kV are discussed. 5000 miles of the U.K. grid are operated at 132 kV and 1000 at 275 kV, ultimately to provide a super grid at 380 kV. Problems are insulation, radio interference and the cost of underground lines (16 times that of overhead lines). Also considered are the economics of the grid as a means of transporting energy and as a means of spreading the peak load over the power stations in the most efficient manner. Finally, the question of amenities is discussed.

  16. Energized overhead ground wires - OHGWs the pioneer Brazilian application

    Energy Technology Data Exchange (ETDEWEB)

    D` Ajuz, Ary; Martinez, Manuel L.B.; Araujo, Ana Maria R; Takai, Mario Noboru; Sganzerla, Flavio [ELETRONORTE, Brasilia, DF (Brazil); O, Junior, Helio P; Fonseca, Claudio S [Marte Engenharia (Brazil); Guimaraes, R P; Mendes, Eloisa R

    1994-12-31

    This paper introduces an economical solution for close HV lines small villages and farms load supply. The needed modifications to adapt a planned transmission system to supply loads located along the lines routes are presented. The paper describes the two overhead ground wires scheme planned for implementation in the 230 kV transmission line under construction by ELETRONORTE in Mato Grosso and Rondonia supplying loads each one totaling roughly 8 MW. (author) 4 refs., 4 figs., 2 tabs.

  17. Single-phase AutoReClosure ARC failure on 400 kV combinedcable/overhead line with permanently connected shunt reactor

    DEFF Research Database (Denmark)

    Bak, Claus Leth; Søgaard, Kim

    2008-01-01

    400 kV power system and initiated by Danish TSO Energinet.dk after having measured the voltage of the cable/overhead line after disconnection. A particular decaying dynamic phase voltage containing voltages higher than the voltage before disconnection appeared. A simulation model for the entire system...

  18. On low-resistance neutral earthing mode in 20 kV overhead and cable networks

    Directory of Open Access Journals (Sweden)

    Mayorov Andrey

    2017-01-01

    Full Text Available The problems of justification and selection of the required single-phase short-circuit current values in cable and overhead networks of 20 kV with low-resistance neutral earthing are considered. It is shown that the desired values of the short-circuit current can be determined on the basis of harmonization of conflicting influencing factors: reliability of the relay protection and automation devices and required resistances of the earthing devices of electrical installations, including personnel safety. In this case, the main influencing factor is the electrical network structure and parameters

  19. Autonomous Inspection Robot for Power Transmission Lines Maintenance While Operating on the Overhead Ground Wires

    Directory of Open Access Journals (Sweden)

    Zheng Li

    2010-12-01

    Full Text Available This paper describes the development of a mobile robot capable of clearing such obstacles as counterweights, anchor clamps, and torsion tower. The mobile robot walks on overhead ground wires in 500KV power tower. Its ultimate purpose is to automate to inspect the defect of power transmission line. The robot with 13 motors is composed of two arms, two wheels, two claws, two wrists, etc. Each arm has 4 degree of freedom. Claws are also mounted on the arms. An embedded computer based on PC/104 is chosen as the core of control system. Visible light and thermal infrared cameras are installed to obtain the video and temperature information, and the communication system is based on wireless LAN TCP/IP protocol. A prototype robot was developed with careful considerations of mobility. The new sensor configuration is used for the claw to grasp the overhead ground wires. The bridge is installed in the torsion tower for the robot easy to cross obstacles. The new posture plan is proposed for obstacles cleaning in the torsion tower. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

  20. Autonomous Inspection Robot for Power Transmission Lines Maintenance While Operating on the Overhead Ground Wires

    Directory of Open Access Journals (Sweden)

    Zheng Li

    2011-01-01

    Full Text Available This paper describes the development of a mobile robot capable of clearing such obstacles as counterweights, anchor clamps, and torsion tower. The mobile robot walks on overhead ground wires in 500KV power tower. Its ultimate purpose is to automate to inspect the defect of power transmission line. The robot with 13 motors is composed of two arms, two wheels, two claws, two wrists, etc. Each arm has 4 degree of freedom. Claws are also mounted on the arms. An embedded computer based on PC/104 is chosen as the core of control system. Visible light and thermal infrared cameras are installed to obtain the video and temperature information, and the communication system is based on wireless LAN TCP/IP protocol. A prototype robot was developed with careful considerations of mobility. The new sensor configuration is used for the claw to grasp the overhead ground wires. The bridge is installed in the torsion tower for the robot easy to cross obstacles. The new posture plan is proposed for obstacles cleaning in the torsion tower. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

  1. Model for the ready definition and approximate comparison of alternative high voltage transmission systems. Phases II and III. Application to electric systems within the contiguous United States. [800 and 1200 kV; 400, 600, and 800 kV dc

    Energy Technology Data Exchange (ETDEWEB)

    1979-08-01

    Research on power delivery alternatives is reported. The first phase of this work was to develop a model of overhead transmission systems in the range of 362 to 1200 kV ac, and +-400 to +-800 kV dc. Such systems included transmission from generation to load and inter-connection of two large integrated systems, with and without the existence of an underlying lower voltage network in either case. This phase has been completed. The second and third phases involved application of the model to electric systems within selected regions of the US, and the entire US, respectively, dealing with real situations and including projected expansion to year 1987. The potential benefits and costs of using higher than existing transmission voltages were to be evaluated on this basis. Additionally, the most advantageous new voltage was to be determined taking into account direct and indirect benefits and costs. The results of the second and third phases are presented.

  2. Tracing overhead transmission line corridors with regard to environmental and spatial qualities

    Directory of Open Access Journals (Sweden)

    Alenka Cof

    2005-01-01

    Full Text Available The article deals with possibilities for running the proposed overhead transmission line Okroglo-Italian border. The Slovene and Italian methods are shown as methods enabling consideration of environmental and spatial impact within the process of planning overhead transmission line corridors. The Slovene method consists of analyses of attractiveness and vulnerability, whereby the first considers those functional and economic factors that affect spatial attractiveness for overhead transmission lines. Thus we can assess the level of economic and functional suitability of alternative routes of the proposed 400 kilovolt overhead transmission line from transformation station Okroglo (Slovenia to Srednje, Golo Brdo and Vrtojba, three potential contact points on the Slovene–Italian border. In accordance with stipulations of the Law on spatial management vulnerability models were prepared, which were used to simulate the development’s potential negative environmental effects and to analyse suitability, which implies harmonisation of development and protection demands. Their result is a possible corridor that can be developed without significant conflicts. The Italian procedure was developed to trace the transmission line corridor from the Slovenian border to the transformation station in Udine. It was also applied on the Slovenian side. Three groups of factors were considered in the procedure: exclusion, repulsion, and attraction. The much simpler procedure enables comparisons, since it uses the same or at least similar spatial data. In conclusion a short commentary is added about the corridor concept as a planning tool.

  3. First 735 kV transmission, Manicouagan, Montreal

    Energy Technology Data Exchange (ETDEWEB)

    Cahill, L

    1964-11-01

    The 735 kV transmission network of Hydro Quebec is described giving reasons for choice of voltage, stability factors level of insulation, disposition of conductors, insulators, equipment used and state of readiness of the project.

  4. Marys Lake 69/115-kV transmission line upgrade and substation expansion projects

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    Western Area Power Administration (Western) and the Platte River Power Authority (Platte River) propose to upgrade portions of the existing electric transmission and substation system that serves the Town of Estes Park, Colorado. The existing transmission lines between the Estes Power Plant Switchyard and the Marys Lake Substation include a 115,000 volt (115-kV) line and 69,000 volt (69-kV) line. Approximately one mile is a double-circuit 115/69-kV line on steel lattice structures, and approximately two miles consists of separate single-circuit 115-kV and a 69-kV lines, constructed on wood H-Frame structures. Both lines were constructed in 1951 by the US Bureau of Reclamation. The existing transmission lines are on rights-of-way (ROW) that vary from 75 feet to 120 feet and are owned by Western. There are 48 landowners adjacent to the existing ROW. All of the houses were built adjacent to the existing ROW after the transmission lines were constructed. Upgrading the existing 69-kV transmission line between the Marys Lake Substation and the Estes Power Plant Switchyard to 115-kV and expanding the Marys Lake Substation was identified as the most effective way in which to improve electric service to Estes Park. The primary purpose and need of the proposed project is to improve the reliability of electric service to the Town of Estes Park. Lack of reliability has been a historical concern, and reliability will always be less than desired until physical improvements are made to the electrical facilities serving Estes Park.

  5. Marys Lake 69/115-kV transmission line upgrade and substation expansion projects

    International Nuclear Information System (INIS)

    1996-05-01

    Western Area Power Administration (Western) and the Platte River Power Authority (Platte River) propose to upgrade portions of the existing electric transmission and substation system that serves the Town of Estes Park, Colorado. The existing transmission lines between the Estes Power Plant Switchyard and the Marys Lake Substation include a 115,000 volt (115-kV) line and 69,000 volt (69-kV) line. Approximately one mile is a double-circuit 115/69-kV line on steel lattice structures, and approximately two miles consists of separate single-circuit 115-kV and a 69-kV lines, constructed on wood H-Frame structures. Both lines were constructed in 1951 by the US Bureau of Reclamation. The existing transmission lines are on rights-of-way (ROW) that vary from 75 feet to 120 feet and are owned by Western. There are 48 landowners adjacent to the existing ROW. All of the houses were built adjacent to the existing ROW after the transmission lines were constructed. Upgrading the existing 69-kV transmission line between the Marys Lake Substation and the Estes Power Plant Switchyard to 115-kV and expanding the Marys Lake Substation was identified as the most effective way in which to improve electric service to Estes Park. The primary purpose and need of the proposed project is to improve the reliability of electric service to the Town of Estes Park. Lack of reliability has been a historical concern, and reliability will always be less than desired until physical improvements are made to the electrical facilities serving Estes Park

  6. EHV/HV Underground Cable Systems for Power Transmission

    DEFF Research Database (Denmark)

    Bak, Claus Leth

    of the transmission system must be re‐thought in order to accommodate the transmission needs for the future. New lines have to be constructed. Transmission lines are usually laid out as overhead lines, which are large structures, i.e. a 400 kV power pylon is 50 meters high. According to public opinion, such power...

  7. Study on the Extremely Low Frequency (ELF) Electromagnetic Field (EMF) emission from overhead High-Voltage Transmission Lines

    International Nuclear Information System (INIS)

    Parthasarathy, S.R.; Roha Tukimin; Wan Saffiey Wan Abdullah; Zulkifli Yusof; Mohd Azizi Mohd Jali

    2016-01-01

    The paper highlights the study on the Extremely Low Frequency (ELF) Electromagnetic Field (EMF) emission performed at an overhead 275-kV High-Voltage Transmission Lines. The study comprised of assessment at the transmission lines on 3 different cases and locations in Klang Valley, specifically on a vacant land near the transmission line, inside and around the house at the vicinity of the transmission line and the area directly under the transmission line. The instrument setup and measurement protocols during the assessment were adopted from standard measurement method and procedures stipulated under the Institute of Electrical and Electronics Engineers (IEEE) Standard. The results were compared with the standards recommended in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The results showed that the measured field strengths are within the safety limit with the highest measured exposure was 10.8 % and 1.8 % of the permissible exposure limit for the electric and magnetic field respectively. Both the field strengths were found to drop significantly against distance from the transmission lines where closer distances showed higher field strengths. Furthermore, the study revealed that buildings and other object such as trees and shrubs screen out the electric field, resulting in a lower value at indoor measurements and near the stated objects. In addition, higher value of electric and magnetic field strengths were recorded when assessment was being done directly under the transmission line compared to the lateral measurement. (author)

  8. Survey of magnetic fields near BPA 230-kV and 500-kV transmission lines

    International Nuclear Information System (INIS)

    Perrin, N.; Aggarwal, R.P.

    1991-01-01

    The purpose of this study was to characterize typical levels and variability of 60Hz magnetic fields at the centerline and edge of right-of-way of Bonneville Power Administration (BPA) 230-kV and 500-kV transmission lines. This was accomplished by taking magnetic field measurements at over 800 spans in Oregon and Washington. The spans were sampled using a stratified random sampling procedure with region (East vs. West), voltage (230-kV vs 500-kV), and circuit configuration as strata. There were five different circuit configuration groups for each region/voltage category requiring a total of 200 strata. Magnetic field measurements were taken at 13 locations under each span using an EMDEX-C as a survey meter. Additional information recorded for each span included conductor height (at 10 locations), right-of-way width, longitudinal and lateral slope, time of day, vegetation, terrain, weather conditions, temperature, wind speed, span length and presence of other lines in the corridor. 9 refs., 17 figs., 26 tabs

  9. California-Oregon 500-kV transmission line development of design criteria

    International Nuclear Information System (INIS)

    Simpson, K.D.

    1990-01-01

    The California-Oregon Transmission Project (COTP) encompassed the design and construction of a third 500-kV ac intertie between California and the Pacific Northwest Transmission system. Sargent ampersand Lundy's (S ampersand L) scope of work in the COTP includes the design of approximately 150 miles of new single-circuit, 500-kV transmission line from southern Oregon to the vicinity of Redding, California. This paper presents the development of the design criteria for this segment of the project, which crosses diverse topographic and climatic regions. This project is an example of the increasing utilization of computers in transmission line engineering. Almost all aspects of design involved the use of the computer. Also, the development of the design criteria for this project coincided with an early release of the TLWorkstation software package by EPRI. TLWorkstation is an engineering workstation containing a family of programs for various aspects of transmission line design. This engineering software allows for increasing refinement in the design and economic optimization of transmission lines and is becoming an important design tool for transmission engineers

  10. Numerical noise analysis for insulator of overhead transmission line

    Science.gov (United States)

    Zhang, Yulin; Chen, Yuwen; Huang, Yu

    2018-04-01

    As an important and complex issue in aero acoustic field, a lot of explorations have been devoted to the wind-induced noise. However, there is still lack of intensive investigations for aerodynamic noise in high-voltage transmission. The overhead transmission line system leads to serious occupational noise exposure in high wind-speed environment, and the noise can even injure the electricians in charge of insulator. By using computational fluid dynamics (CFD) which combined with computational aero acoustics (CAA), this paper predicts the noise generated by insulator of high voltage electricity transmission line which explores in wind environment. The simulation results indicate that the wind velocity, the assembly angle of the insulator and its ribs' distribution are the main contributory factors for the aerodynamic noise. Specifically, when wind velocity is greater than 15m/s, the alteration of noise is not sensitive to the wind velocity; furthermore, when the assembly angle increases from 0°to 60°, the noise decreases gradually, however, if the angle is happening to be 75°or 90°, it would be even greater than that at 0°. In order to inhibit the aerodynamic noise, it is necessary to control the flow blowing across the boundary of the insulator. Consequently, the result indicates that if the outermost rib is shorter than the second one, the noise reduced evidently. This information expects to provide useful help for the extremely suppression of aerodynamic noise, and also supply practical reference material for the design and application of overhead transmission line system.

  11. Maintenance planning for transmission routes with medium voltage overlines - experience within the framework of two pilot projects; Trassenpflegeplanung fuer Mittel- und Hochspannungsfreileitungen - Erfahrungen von zwei Pilotprojekten

    Energy Technology Data Exchange (ETDEWEB)

    Geiges, H. [Ingenieurbuero Geiges, Freiraum- und Landschaftsplanung, Laumersheim (Germany)

    1997-11-03

    On the basis of the `VDEW Orientation Aid for Maintenance Measures in Transmission Routes` two pilot projects were selected in a 110 kV and a 20 kV overhead transmission route. (orig.) [Deutsch] Auf der Grundlage der `VDEW-Orientierungshilfe zu Pflegemassnahmen in Leitungstrassen` wurden Pilotprojekte in einer 110-kV- und in einer 20-kV-Freileitungstrasse im suedlichen Pfaelzerwald ausgewaehlt. (orig.)

  12. Power System Reliability Assessment by Analysing Voltage Dips on the Blue Horizon Bay 22KV Overhead Line in the Nelson Mandela Bay Municipality

    Science.gov (United States)

    Lamour, B. G.; Harris, R. T.; Roberts, A. G.

    2010-06-01

    Power system reliability problems are very difficult to solve because the power systems are complex and geographically widely distributed and influenced by numerous unexpected events. It is therefore imperative to employ the most efficient optimization methods in solving the problems relating to reliability of the power system. This paper presents a reliability analysis and study of the power interruptions resulting from severe power outages in the Nelson Mandela Bay Municipality (NMBM), South Africa and includes an overview of the important factors influencing reliability, and methods to improve the reliability. The Blue Horizon Bay 22 kV overhead line, supplying a 6.6 kV residential sector has been selected. It has been established that 70% of the outages, recorded at the source, originate on this feeder.

  13. Lightning simulation of a combined overhead line/cable connected GIS

    DEFF Research Database (Denmark)

    Kessel, Jakob; Atlason, Vioir; Bak, Claus Leth

    2008-01-01

    performance, compared to a system consisting solely of AIS connected thorugh overhead lines. The main purpose is to investigate whether overvoltage protection is necessary at the GIS busbar. Here, the price for a GIS SA is significantly more expensive than the price for an AIS SA. The analysis is conducted......The paper concerns different investigations of lightning simulation of a combined 170 kV overhead line/cable connected GIS. This is interesting due to the increasing amount of underground cables and GIS in the Danish transmission system. This creates a different system with respect to lightning...... by implementing a simulation model in PSCAD/EMTDC. Simulations are conducted for both SF and BFO where the overvoltage at the transformer are evaluated as this component has the lowest insulation strength. The overvoltages are evaluated for different front imes of the lightning surge, different soil resistivities...

  14. Electric power transmission for a Hanford Nuclear Energy Center (HNEC)

    International Nuclear Information System (INIS)

    1975-09-01

    The major issues examined in the comparison of the DIST and HNEC transmission concepts are: (1) type of transmission to be employed and an assessment of its technical feasibility, (2) availability of rights-of-way, (3) economics, (4) environmental impact, and (5) overall reliability of the transmission system. The type of transmission selected for bulk power transfer from an HNEC for the time period studied is overhead AC, 500 kV double or single circuit, a voltage currently used in the PNW system. This type of system can accommodate growth up to at least 23,000 MW of thermal capacity at an HNEC. Significant additional transmountain capacity needs would require 1100 kV transmission, which should be technologically proved by the end of the 1970s. (auth)

  15. A Study of Electromagnetic Radiation of Corona Discharge Near 500-Kv Electric Installations

    International Nuclear Information System (INIS)

    Korzhov, A. V.; Okrainskaya, I. S.; Sidorov, A. I.; Kufel'd, V. D.

    2004-01-01

    Data on the spectral composition and intensity of electromagnetic radiation of corona discharge are obtained in an experimental study performed on the outdoor switchgear of the Shagol 500-kV substation of the Chelyabinsk Enterprise of Trunk Transmission Grids and under a 500-kV Shagol - Kozyrevo overhead transmission line. The electromagnetic environment on the territory of the 500-kV outdoor switchgear is shown to be determined by narrow-band radiations (harmonics of the frequency of electric supply) and wide-band radiations due to corona discharges of high-voltage sources. This means that the personnel experience the action of a commercial-frequency electric field and electromagnetic radiation of a quite wide range, which is not allowed for by the existing guidelines. It is recommended to continue the study in cooperation with medical institutions in order to create guidelines that would allow for the joint action of commercial-frequency electric field and electromagnetic radiation and for the voltage in the line, the current load, the meteorological situation, and other factors

  16. Risk assessment of 170 kV GIS connected to combined cable/OHL network

    DEFF Research Database (Denmark)

    Bak, Claus Leth; Kessel, Jakob; Atlason, Vidir

    2009-01-01

    performance, compared to a system consisting solely of AIS connected through overhead lines. The main purpose is to investigate whether overvoltage protection is necessary at the GIS busbar. The analysis is conducted by implementing a simulation model in PSCAD/EMTDC. Simulations are conducted for both SF......This paper concerns different investigations of lightning simulation of a combined 170 kV overhead line/cable connected GIS. This is interesting due to the increasing amount of underground cables and GIS in the Danish transmission system. This creates a different system with respect to lightning...... and BFO. Overvoltages are evaluated for varying front times of the lightning surge, different soil resistivities at the surge arrester grounding in the overhead line/cable transition point and a varying length of the connection cable between the transformer and the GIS busbar with a SA implemented...

  17. Using ice melting and ice rolling technologies to remove ice from sub-transmission and transmission lines at Manitoba Hydro

    International Nuclear Information System (INIS)

    Farias, A. R.

    1999-01-01

    Development of an of an Ice Storm Management program by Manitoba Hydro to reduce ice storm damage to its 8 kV feeders to 115 kV transmission lines, is discussed. The program consists of the de-icing of overhead lines, either by ice melting, or ice rolling. Ice melting involves the placement of a three-phase short at a calculated point. The term ice rolling denotes a process of mechanically stripping the ice from conductors. The most recent major ice storm experienced by Manitoba Hydro was in the winter of 1997/1998. During the period from February 6 to February 17, 1998, a total of 83 'ice melt' procedures were performed to melt the ice from 2,628 km of overhead line (7,883 km of conductor), in addition to 'ice rolling'. This paper describes Manitoba Hydro's 25-years' experience with ice melting and it also describes the advantages and disadvantages of both ice melting and ice rolling. Although not a panacea to combat the effects of ice storms, ice melting was found to be the most effective way of removing ice from overhead transmission and sub-transmission lines. Ice rolling was also found to be effective. Other tools that have been found to be useful by various utilities in combating ice storm damage include improved structure and line design, system design that provide more redundancies and emergency sources, and standby generators at critical load points

  18. Analysis of a back flashover across insulator strings on a 115 kV transmission line tower by PSCAD

    Directory of Open Access Journals (Sweden)

    Worakit Anekthanasuwan

    2015-09-01

    Full Text Available Lightning striking on a transmission tower induces high ground potential rise and high voltage at tower arms in which potential is normally at ground level, and subsequently causes overvoltage across an insulator string. If this overvoltage is higher than the withstanding voltage of the insulator string according to the v-t (voltage-time curve, back flashover phenomena will occur and this event may cause outage. The main objective of this paper is to study the factors influencing the back flashover phenomena. The computer program PSCAD/EMTDC (Power System Computer Aided Design/Electromagnetic Transients including DC is used to simulate lightning striking on a transmission tower 115kV. Lightning current, transmission towers, ground resistance, insulator strings and back flashover phenomena are modeled. Main simulations are lightning striking on different towers, different soil resistivity, different lightning current magnitudes and wave shapes, different locations, and different phase angles of source voltage. Simulation results show that the higher tower encounters higher induced voltage. A back flashover occurs at the top tower arm easier than at the middle and lower arms. The higher soil resistivity induces higher voltage. The larger lightning current magnitude impacts on higher induced voltage. The longer rise time of lightning current generates lower induced voltage. Lightning strikes directly on tower generate higher voltage than that of striking on overhead ground wires.

  19. Voltage Analysis Improvement of 150 kV Transmission Subsystem Using Static Synchronous Compensator (STATCOM)

    Science.gov (United States)

    Akbar, P. A.; Hakim, D. L.; Sucita, T.

    2018-02-01

    In this research, testing improvements to the distribution voltage electricity at 150 kV transmission subsystem Bandung Selatan and New Ujungberung using Flexible AC Transmission System (FACTS) technology. One of them is by doing the control of active and reactive power through the power electronics equipment Static Synchronous Compensator (STATCOM). The subsystem is tested because it has a voltage profile are relatively less well when based on the IEEE / ANSI C.84.1 (142.5 - 157.5 kV). This study was conducted by analyzing the Newton-Raphson power flow on the simulator DigSilent Power Factory 15 to determine the profile of the voltage (V) on the system. Bus which has the lowest voltage to be a reference in the installation of STATCOM. From this research is known that the voltage on the conditions of the existing bus 28, as many as 21-23 still below standard buses (142.5 kV), after the installation is done using STATCOM, voltage on the buses improved by increasing the number of tracks that follow the standard / is in the range 142.5 kV -157.5 kV as many as 23-27 buses or 78.6% - 96%, with the optimum mounting on a bus Rancaekek STATCOM II with a capacity of 300 MVA.

  20. Technical and economic feasibility of superconducting power transmission: a case study

    International Nuclear Information System (INIS)

    Forsyth, E.B.; Mulligan, G.A.; Beck, J.W.; Williams, J.A.

    1975-01-01

    The long-range plans of the Long Island Lighting Company include the installation of 4600 MW of generation capacity at nuclear sites on eastern Long Island by the 1990's. A single site, Shoreham, was chosen for this study which would require transmission facilities to the Ruland Road substation, 43 miles away. Conventional 345 kV overhead and underground circuits are planned for this service. For the case study three superconducting cable schemes have been investigated which reflect various technical options. The superconducting cables have been designed to meet acceptable normal and contingency load flow conditions and to withstand maximum short circuit faults. A cost analysis has been made of the complete installation, providing a valuable comparison of the estimated cost of this new technology with conventional methods. The most favorable cost comparison is a two-circuit 345 kV superconducting system, which appears to be about one-half the cost of an all underground 345 kV high pressure oil-filled cable system. No reactive compensation will be required for the superconducting system, whereas extensive compensation is required for HPOF cables over the same distance. The cost estimate for the two-circuit superconducting system is about twice that of 345 kV overhead transmission, which would consist of two double circuits and one single circuit, assuming right-of-way could be obtained. (U.S.)

  1. Measurements of Voltage Harmonics in 400 kV Transmission Network

    Directory of Open Access Journals (Sweden)

    Ryszard Pawełek

    2014-06-01

    Full Text Available The paper deals with the analysis of voltage harmonics measurements performed in the 400 kV transmission network. The voltage was measured by means of three transducers: resistive voltage divider, inductive measuring transformer and capacitive voltage measuring transformer. Instrument errors were estimated for measuring transformers with reference to the harmonic values obtained from the voltage divider.

  2. Comparison between IEEE and CIGRE Thermal Behaviour Standards and Measured Temperature on a 132-kV Overhead Power Line

    Directory of Open Access Journals (Sweden)

    Alberto Arroyo

    2015-12-01

    Full Text Available This paper presents the steady and dynamic thermal balances of an overhead power line proposed by CIGRE (Technical Brochure 601, 2014 and IEEE (Std.738, 2012 standards. The estimated temperatures calculated by the standards are compared with the averaged conductor temperature obtained every 8 min during a year. The conductor is a LA 280 Hawk type, used in a 132-kV overhead line. The steady and dynamic state comparison shows that the number of cases with deviations to conductor temperatures higher than 5 ∘ C decreases from around 20% to 15% when the dynamic analysis is used. As some of the most critical variables are magnitude and direction of the wind speed, ambient temperature and solar radiation, their influence on the conductor temperature is studied. Both standards give similar results with slight differences due to the different way to calculate the solar radiation and convection. Considering the wind, both standards provide better results for the estimated conductor temperature as the wind speed increases and the angle with the line is closer to 90 ∘ . In addition, if the theoretical radiation is replaced by that measured with the pyranometer, the number of samples with deviations higher than 5 ∘ C is reduced from around 15% to 5%.

  3. Impact of Considering 110 kV Grid Structures on the Congestion Management in the German Transmission Grid

    Science.gov (United States)

    Hoffrichter, André; Barrios, Hans; Massmann, Janek; Venkataramanachar, Bhavasagar; Schnettler, Armin

    2018-02-01

    The structural changes in the European energy system lead to an increase of renewable energy sources that are primarily connected to the distribution grid. Hence the stationary analysis of the transmission grid and the regionalization of generation capacities are strongly influenced by subordinate grid structures. To quantify the impact on the congestion management in the German transmission grid, a 110 kV grid model is derived using publicly available data delivered by Open Street Map and integrated into an existing model of the European transmission grid. Power flow and redispatch simulations are performed for three different regionalization methods and grid configurations. The results show a significant impact of the 110 kV system and prove an overestimation of power flows in the transmission grid when neglecting subordinate grids. Thus, the redispatch volume in Germany to dissolve bottlenecks in case of N-1 contingencies decreases by 38 % when considering the 110 kV grid.

  4. Novel adaptive distance relay algorithm considering the operation of 154 kV SFCL in Korean power transmission system

    International Nuclear Information System (INIS)

    Lee, S.; Lee, J.; Song, S.; Yoon, J.; Lee, B.

    2015-01-01

    Highlights: • This paper presents an outline of the new project of the 154 kV SFCL in Korea. • And then we review some protection problems for the application of 154 kV SFCLs. • This paper proposes a new adaptive protection algorithm for 154 kV SFCLs. • The developed algorithm is tested in a simple distance relay system. - Abstract: In general, SFCLs can have a negative impact on the protective coordination in power transmission system because of the variable impedance of SFCLs. It is very important to solve the protection problems of the power system for the successful application of SFCLs to real power transmission system. This paper reviews some protection problems which can be caused by the application of 154 kV SFCLs to power transmission systems in South Korea. And then we propose an adaptive protection algorithm to solve the problems. The adaptive protection algorithm uses the real time information of the SFCL system operation.

  5. Composite Materials in Overhead Lines

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard; Holbøll, Joachim

    2009-01-01

    towers and recently conductors based on composite materials are available at transmission levels. In this paper it is investigated which composite based solutions are available in connection with complete overhead line systems including insulators, towers and conductors. The components are reviewed......The use of composite materials, e.g. fibreglass materials, in overhead transmission line systems is nothing new. Composite based insulators have been applied to transmission lines for over 30 years, mainly as suspension and post insulators and often as an option for special applications. Also...... with respect to solved and persisting known failures/problems of both mechanical and electrical nature. Major challenges related to extensive use of composite materials in an overhead line system are identified, as are possible benefits - both when using standard as well as customised composite components, e...

  6. A theoretical model of rain–wind–induced in-plane galloping on overhead transmission tower-lines system

    Directory of Open Access Journals (Sweden)

    Chao Zhou

    2015-09-01

    Full Text Available Rain–wind–induced galloping phenomenon often occurs on overhead transmission tower-lines system, just as icing galloping and vortex-excited vibration; this kind of instability oscillation can cause power-line breakage or tower failure. However, the existing theoretical models of rain–wind–induced galloping are mainly based on the hypothesis of the overhead power-lines with fixed ends, which is inconsistent with the actual operation situation. Therefore, this article thus presents a preliminary theoretical study and proposes a new theoretical model taking into account the effect of tower excitations on the in-plane galloping of the overhead power-line and on the motion of the upper rain-line. The theoretical model is solved by Galerkin method and verified by the comparison with the test data obtained in the available literature involved with the overhead power-lines with fixed towers or moving towers. It turns out that the tower excitations may intensify the in-plane galloping amplitude of the overhead power-line within a certain range of frequency ratio and enable better comprehension of rain–wind–induced galloping mechanism.

  7. Proposal to amend existing operating permit for the Ault-Craig 345-kV and Hayden-Archer 230-kV transmission lines, Routt, Jackson and Larimer Counties, Colorado

    International Nuclear Information System (INIS)

    1997-08-01

    The Western Area Power Administration, Rocky Mountain Region, is proposing to amend an existing US Forest Service operating permit for the Ault-Craig 345-kV and Hayden-Archer 230-kV transmission lines, which are located in Routt, jackson, and Larimer counties, Colorado. These transmission lines cross portions of the Roosevelt and Routt National Forests. The long-term use authorization Western is requesting from the Forest Service would be for the life of the Ault-Craig and Hayden-Archer transmission lines. This environmental assessment addresses those access road and right-of-way maintenance activities identified by Western that would be performed on Forest Service managed lands during the next approximately five years

  8. Proposal to amend existing operating permit for the Ault-Craig 345-kV and Hayden-Archer 230-kV transmission lines, Routt, Jackson and Larimer Counties, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-01

    The Western Area Power Administration, Rocky Mountain Region, is proposing to amend an existing US Forest Service operating permit for the Ault-Craig 345-kV and Hayden-Archer 230-kV transmission lines, which are located in Routt, jackson, and Larimer counties, Colorado. These transmission lines cross portions of the Roosevelt and Routt National Forests. The long-term use authorization Western is requesting from the Forest Service would be for the life of the Ault-Craig and Hayden-Archer transmission lines. This environmental assessment addresses those access road and right-of-way maintenance activities identified by Western that would be performed on Forest Service managed lands during the next approximately five years.

  9. Rugi Daya Dan Energi Akibat Korona Pada Saluran Udara Tegangan Ekstra Tinggi (SUTET 500 Kv

    Directory of Open Access Journals (Sweden)

    Muhamad Haddin

    2018-01-01

    Full Text Available The use of extra high voltage in electrical power transmission system causing corona. A visual corona phenomenon shown by the appearance of visible light radiation, hissing noise, ozone formation and power losses. The impact of corona affect the environment surrounding the overhead line transmission and power losses in the line. This research discusses power and energy losses due to corona by using quantitative method. Calculations performed by calculating relative air density values, disruptive critical voltages, power losses and corona energy. The research object was taken by extra high voltage  overhead line transmission 500kV Tanjung Jati B Power Plant to Ungaran Substation.The result show that corona power losses are 0.41-0.44 kW/mil (0.25-0.27kw/km per phase, with total 1.25-1.30kW/mil (0.78-0.81k/w/km. corona power losses 107.57-112.08 kW along of line. Average of corona energy losses obtained 2642.67 kWh. The percentage of corona power losses to electrical power supplied is between 0.005% to 0.011%.

  10. A modelling approach for railway overhead line equipment asset management

    OpenAIRE

    Kilsby, Paul; Remenyte-Prescott, Rasa; Andrews, John

    2017-01-01

    The Overhead Line Equipment (OLE) is a critical sub-system of the 25kV AC overhead railway electrification system. If OLE asset management strategies can be evaluated using a whole lifecycle cost analysis that considers degradation processes and maintenance activities of the OLE components, the investment required to deliver the level of performance desired by railway customers and regulators can be based on evidence from the analysis results. A High Level Petri Net (HLPN) model, proposed in ...

  11. Overhead distribution line models for harmonics studies

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, M.; Xu, W.; Dommel, H.W.

    1994-01-01

    Carson's formulae and Maxwell's potential coefficients are used for calculating the per unit length series impedances and shunt capacitances of the overhead lines. The per unit length values are then used for building the models, nominal pi-circuit, and equivalent pi-circuit at the harmonic frequencies. This paper studies the accuracy of these models for presenting the overhead distribution lines in steady-state harmonic solutions at frequencies up to 5 kHz. The models are verified with a field test on a 25 kV distribution line and the sensitivity of the models to ground resistivity, skin effect, and multiple grounding is reported.

  12. Environmental Assessment of the Gering-Stegall 115-kV Transmission Line Consolidation Project, Scotts Bluff County, Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The Department of Energy (DOE), Western Area Power Administration (Western) proposes to consolidate segments of two transmission lines near the Gering Substation in Gering, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska, within the city of Gering. Presently, there are three parallel 115-kilovolt (kV) transmission lines on separate rights-of-way (ROW) that terminate at the Gering Substation. The project would include dismantling the Archer-Gering wood-pole transmission line and rebuilding the remaining two lines on single-pole steel double circuit structures. The project would consolidate the Gering-Stegall North and Gering-Stegall South 115-kV transmission lines on to one ROW for a 1.33-mile segment between the Gering Substation and a point west of the Gering Landfill. All existing wood-pole H-frame structures would be removed, and the Gering-Stegall North and South ROWs abandoned. Western is responsible for the design, construction, operation, and maintenance of the line. Western prepared an environmental assessment (EA) that analyzed the potential environmental impacts of the proposed construction, operation, and maintenance of the 115-kV transmission line consolidation. Based on the analyses in the EA, the DOE finds that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act of 1969 (NEPA).

  13. Environmental Assessment of the Gering-Stegall 115-kV Transmission Line Consolidation Project, Scotts Bluff County, Nebraska

    International Nuclear Information System (INIS)

    1995-05-01

    The Department of Energy (DOE), Western Area Power Administration (Western) proposes to consolidate segments of two transmission lines near the Gering Substation in Gering, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska, within the city of Gering. Presently, there are three parallel 115-kilovolt (kV) transmission lines on separate rights-of-way (ROW) that terminate at the Gering Substation. The project would include dismantling the Archer-Gering wood-pole transmission line and rebuilding the remaining two lines on single-pole steel double circuit structures. The project would consolidate the Gering-Stegall North and Gering-Stegall South 115-kV transmission lines on to one ROW for a 1.33-mile segment between the Gering Substation and a point west of the Gering Landfill. All existing wood-pole H-frame structures would be removed, and the Gering-Stegall North and South ROWs abandoned. Western is responsible for the design, construction, operation, and maintenance of the line. Western prepared an environmental assessment (EA) that analyzed the potential environmental impacts of the proposed construction, operation, and maintenance of the 115-kV transmission line consolidation. Based on the analyses in the EA, the DOE finds that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act of 1969 (NEPA)

  14. Back-to-Back Energization of a 60kV Cable Network - Inrush Currents Phenomenon

    DEFF Research Database (Denmark)

    Faria da Silva, Filipe; Bak, Claus Leth; Hansen, M. Lind

    2010-01-01

    On November 2008 the Danish government decided that all Danish transmission lines with a rated voltage equal to and below 150kV must be put underground, in order to reduce the visual pollution caused by Overhead Lines. This decision will lead to a massive use of underground cables in the Danish...... Network, and force a change in the approach used until now when planning, analyzing and operating electrical power systems. One problem that might arise is the energization of cables in parallel, as this operation may originate high inrush currents, which represent a risk to the circuit breakers connected...

  15. Research on Line Patrol Strategy of 110kV Transmission Line after Lightning Strike

    Directory of Open Access Journals (Sweden)

    Li Mingjun

    2016-01-01

    Full Text Available Lightning faults occupy in the majority of instantaneous fault and reclosing can usually be successful, so power supply can be restored without immediate patrol in many cases. Firstly, this paper introduces the lightning fault positioning and identifying method. Then test electrical performance of insulators after lightning strike from 110kV lines. Data shows that lightning strike has little effect on the electric performance of insulator. Finally, illustrating disposal process of the 110 kV transmission line after lightning fault, certifying that the power supply reliability be ensured without line patrol.

  16. Wild Horse 69-kV transmission line environmental assessment

    International Nuclear Information System (INIS)

    1996-12-01

    Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline's pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE's review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest

  17. Wild Horse 69-kV transmission line environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline`s pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE`s review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest.

  18. STUDY ON PERFORMANCE OF 21M 132kV TRANSMISSION TOWER WITH MEDIUM WIND INTENSITY

    OpenAIRE

    V. LAKSHMI; A. RAJAGOPALA RAO

    2012-01-01

    Electric Power is today playing an increasingly important role in the life of the community. In the electric power system the production and transmission of power are two predominant factors. For the purpose of transmission of electricity towers are the main medium with some wires at required distances and altitudes. The remotehydroelectric power plants have given rise to the need for extra high voltage. Prior to 1950, 150 kV electric transmission lines were considered and still higher voltag...

  19. French 400 kV network

    Energy Technology Data Exchange (ETDEWEB)

    Pelissier, R

    1965-11-01

    A 400 kV transmission network has been constructed to carry hydroelectric power from the Alps and the Massif Central to Paris at peak hours and to carry power in the reverse direction in off-peak hours. A double circuit-ring at 400 kV encircling the Paris region is also nearing completion. Measures have to be taken to counter the very high short-circuit currents in such a network. A 730 kV network will eventually become necessary. The consequent multiplicity of transmission voltages will give rise to further problems. Collaboration with neighboring countries is envisaged. The problems of stability and synchronization posed by the new system are described and solutions suggested. The new circuit-breaking requirements are discussed, and details of tower design for 400 kV and 730 kV are given.

  20. VT Green Mountain Power Line Data (Overhead Only)

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) Green Mountain Power (GMP) pole and OVERHEAD linear distribution/sub-transmission model data. THE LINEAR DISTRIBUTION LAYER ONLY INCLUDES OVERHEAD...

  1. Full Scale Experimental Study on the Air Insulation of 765kV Transmission Lines

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Boo; Shin, Jeong Woon; Cho, Sung Bae; Chang, Sung Chil; Kwak, Joo Shik [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Kim, Ik Soo; Lee, Heyoung Ho; Kang, Young Sik; Lee, Hong Sik; Choi, Beyoung Joo; Kim, Young Bae [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of)

    1997-12-31

    Design and construction of testing yard. Technical specification of impulse voltage generator which was installed in testing yard. Corrosion and statistical analysis of test data. Test object setup and test results of flashover characteristic in various paths. Recommended optimum air clearance of 765kV transmission lines. (author). 163 refs., figs.

  2. The Way of Reducing Current Values in Optical Ground Wires at Asymmetrical Faults on Overhead Transmission Lines

    Directory of Open Access Journals (Sweden)

    Egamnazarov Georgiy

    2016-12-01

    Full Text Available Given the fact that the installing costs of an optical ground wire on overhead lines directly depend on its cross-section, which in turn depends on the level of fault current it should withstand, in order to reduce these current values in the optical ground wire, I suggested performing its isolated descents from the end towers of the line with its transition to an optical cable. The research was carried out on the example of a 500 kV overhead line in the National Electric Power Grid. The Method of Symmetrical Components for calculating asymmetrical fault currents was not used; therefore, calculations were carried out on the base of presenting the line as a multi-wire system for the considered case as a five-wire system (optical ground wire, steel ground wire, and three phase wires. Such approach allows taking into account the initial asymmetry of the line parameters and modeling any kind of asymmetrical faults. The analyses of calculated results were performed. The conclusive evidence that the optical ground wire isolated descents from the end towers of the line give the possibility of reducing the level of maximal fault current distribution values in it and therefore its cross section, is presented.

  3. Transmission line undergrounding : rate impact investigation and analysis

    International Nuclear Information System (INIS)

    2004-01-01

    In response to concerns expressed by the residents of Markham, Ontario regarding the possible environmental and health impacts of a proposed 230 kV overhead transmission line, Hydro One Networks Inc. (HONI) has proposed to place the line underground as an alternative. This analysis was prepared to evaluate the potential impacts on transmission rates and consumer prices related to changes in the level of underground construction of transmission lines by HONI, as opposed to overhead construction. The report presents the approach to data collection; cost estimates and projections; the modeling and projecting of HONI's regulated rate base and revenue requirement on a basis that reflects the manner in which its future transmission rates are expected to be established; estimates of the incremental cost of undergrounding reflecting a range of reasonable assumptions; and a comparison of the resulting transmission costs and total customer bill. To address the issue of potential demand in other municipalities for additional undergrounding, the study also examined the cumulative effects of ten years' incremental undergrounding costs (i.e. effects on 2014 rates). It was concluded that if HONI were to implement an undergrounding program beginning in 2005, resulting in the installation of 80 km of underground lines by 2014, and shared costs by all users of HONI's system through the network transmission charges, the 2014 transmission rates would be higher. 5 tabs

  4. Choice of 735 kV transmission economics and system performance

    Energy Technology Data Exchange (ETDEWEB)

    McGillis, D T

    1966-01-01

    The present Hydro Quebec load is 8,000 MW and is expected to be 16,000 MW by the late 1970's and 26,000 MW by the middle of the 1980's. This load is concentrated in the area along the St. Lawrence River between Quebec City and Montreal where most of Quebec's six million people live. Fortunately there is in the Province of Quebec enough hydroelectric potential to meet the increase in load that is expected to develop over the next 15 to 20 years. These new sources are, however, at least 500 miles away from the Montreal-Quebec load area. Though this consideration had some bearing on the planning of the Hydro-Quebec ehv network, the choice of 735 kV transmission for the Manicouagan-Outardes project was based principally on economic studies of alternative transmission facilities for this specific project.

  5. Concept design of the high voltage transmission system for the collider tunnel

    International Nuclear Information System (INIS)

    Norman, L.S.

    1992-03-01

    In order to provide electrical service to the Superconducting Super Collider Laboratory (SSCL) 54-mile-circumference collider of 125 MVA at 69 kV or 155 MVA at 138 kV of distributed power, it must be demonstrated that the concept design for a high-voltage transmission system can meet the distribution requirements of the collider electrical system with its cryogenic system's large motor loads and its pulsed power technical systems. It is a practical design, safe for operating personnel and cost-effective. The normal high-voltage transmission techniques of overhead and underground around the 54-mile collider tunnel could not be applied because of technical and physical constraints, or was environmentally unacceptable. The approach taken to solve these problems is the installation of 69-kV or 138-kV exposed solid dielectric transmission cable inside the collider tunnel with the superconducting magnets, cryogenic piping, electrical medium, and low-voltage distribution systems, and electronic/instrumentation wiring systems. This mixed-use approach has never been attempted in a collider tunnel. Research into all aspects of the engineering and installation problems and consultation with transmission cable manufacturers, electrical utilities, and European entities with similar installations -- such as the Channel Tunnel -- demonstrate that the concept design is feasible and practical. This paper presents a history of the evolution of the concept design. Design studies are underway to determine the system configuration and voltages. Included in this report are tunnel transmission cable system considerations and evaluation of solid dielectric high-voltage cable design

  6. Concept design of the high-voltage transmission system for the collider tunnel

    International Nuclear Information System (INIS)

    Norman, L.S.

    1992-01-01

    In order to provide electrical service to the Superconducting Super Collider Laboratory (SSCL) 54-mile-circumference collider of 125 MVA at 69 kV or 155 MVA at 138 kV of distributed power, it must be demonstrated that the concept design for a high-voltage transmission system can meet the distribution requirements of the collider electrical system with its cryogenic system's large motor loads and its pulsed power technical systems. It is a practical design, safe for operating personnel and cost-effective. The normal high-voltage transmission techniques of overhead and underground around the 54-mile collider tunnel could not be applied because of technical and physical constraints, or was environmentally unacceptable. The approach taken to solve these problems is the installation of 69-kV or 138-kV exposed solid dielectric transmission cable inside the collider tunnel with the superconducting magnets, cryogenic piping, electrical medium, and low-voltage distribution systems, and electronic/instrumentation wiring systems. This mixed-use approach has never been attempted in a collider tunnel. Research into all aspects of the engineering and installation problems and consultation with transmission cable manufacturers, electrical utilities, and European entities with similar installations-such as the Channel Tunnel-demonstrate that the concept design is feasible and practical. This paper presents a history of the evolution of the concept design. Design studies are underway to determine the system configuration and voltages. Included in this report are tunnel transmission cable system considerations and evaluation of solid dielectric high-voltage cable design

  7. Weld-Windsor 115-kV Transmission Line Project, Weld County, Colorado

    International Nuclear Information System (INIS)

    1996-05-01

    The Western Area Power Administration is proposing to rebuild a 3.0 mile segment of the existing Flatiron-Weld 115-kV transmission line in Weld County. The line would be reconductored with new conductor on new wood pole double circuit structures. The new structures would support a double circuit transmission line configuration. The first circuit would be owned by Western and the second by Public Service Company of Colorado (PSCO). Alternatives considered included no action, constructing PSCO's circuit on new right-of-way, and reconductoring Western's existing line on the same structures. The proposed action was selected because it provided an opportunity to share structures with PSCO and, overall, would minimize costs and environmental impacts. The environmental assessment identifies minor effects on existing natural or human resources and minor benefits for agricultural operations

  8. Overhead Transmission Lines Deicing under Different Incentive Displacement

    Directory of Open Access Journals (Sweden)

    Qing He

    2014-01-01

    Full Text Available Overhead transmission line icing is one of the main factors affecting safety and reliability of power grid. This paper proposed an excitation deicing method of iced wire and theoretically revealed the ice removal mechanism under displacement excitation conditions, by taking the LGJ-70/10 glaze icing wire as the 3D model and analyzing and studying its dynamic response under the effect of displacement excitation. The simulation results show that the stress of wire icing area is enlarged with the increase of excitation displacement and frequency. Through the comparison of the compression strength experimental results on a series of different iced wires in low temperature environment, the authors found out that the stress generated from the wire icing area is greater than the crushing strength of the ice within the scope of the calculation parameters, which proved the validity and the feasibility of the method, and finally the suitable excitation displacement is determined. Following studies show that, as far as possible, it is necessary to reduce the incentive displacement and also to select the appropriate constraint length in order to avoid the line jumping that may be caused by large span ice shedding.

  9. The 12th 735-kV transmission line project: Hydro-Quebec network

    International Nuclear Information System (INIS)

    1992-01-01

    Hydro-Quebec is proposing to construct a 735-kV transmission line from the Chissibi station near the LG3 hydroelectric power plant to the Jacques-Cartier station near Quebec City. The width of the right-of-way will generally be 90 m and it is intended to install the line in two stages. The Chissibi-Chibougamau section should enter service in 1993 and the Chibougamau-Cartier section in 1994. The cost of the line is estimated at $1.21 billion, of which $900 million is for line construction and $310 million for station equipment. Prospective corridors for the line route have been selected, portions of which enable twinning with Hydro-Quebec's existing 9th 735-kV line. A series of hearings on the environmental and other impacts of the power line project was held by the Bureau d'audiences publiques sur l'environnement and results are summarized along with the views of the Bureau. The summary describes the justification for the project, the choice of the transmission line route, the evaluation of the impacts of the project on the natural and human environments, health effects due to magnetic fields, and effects on the economic development of northern Quebec. Recommendations are given for mitigating the impacts of the project. 13 refs., 8 figs., 2 tabs

  10. 75 FR 9573 - Minnkota Power Cooperative, Inc: Bemidji-Grand Rapids 230kV Transmission Project

    Science.gov (United States)

    2010-03-03

    ... Rapids 230kV Transmission Project AGENCY: Rural Utilities Service, USDA. ACTION: Notice of Availability... copy of the Draft EIS may be viewed online at the following Web sites: http://www.usda.gov/rus/water..., Longville, MN 56655; Walker Public Library, 207 4th St., Walker, MN 56484; Bovey Public Library--Village...

  11. To Solution of Classical Problem Pertaining to Magnetic Interference of Overhead Power Transmission Line on Extended Conducting Communications

    Directory of Open Access Journals (Sweden)

    V. I. Glushko

    2013-01-01

    Full Text Available The paper considers a problem pertaining to magnetic interference of overhead power transmission lines and high-voltage bus bars of electrical installations on extended conducting communications and secondary circuits of relay protection and automation. A simplified task solution has been obtained on the basis of the Carson integral approximation.

  12. Obstacle negotiation control for a mobile robot suspended on overhead ground wires by optoelectronic sensors

    Science.gov (United States)

    Zheng, Li; Yi, Ruan

    2009-11-01

    Power line inspection and maintenance already benefit from developments in mobile robotics. This paper presents mobile robots capable of crossing obstacles on overhead ground wires. A teleoperated robot realizes inspection and maintenance tasks on power transmission line equipment. The inspection robot is driven by 11 motor with two arms, two wheels and two claws. The inspection robot is designed to realize the function of observation, grasp, walk, rolling, turn, rise, and decline. This paper is oriented toward 100% reliable obstacle detection and identification, and sensor fusion to increase the autonomy level. An embedded computer based on PC/104 bus is chosen as the core of control system. Visible light camera and thermal infrared Camera are both installed in a programmable pan-and-tilt camera (PPTC) unit. High-quality visual feedback rapidly becomes crucial for human-in-the-loop control and effective teleoperation. The communication system between the robot and the ground station is based on Mesh wireless networks by 700 MHz bands. An expert system programmed with Visual C++ is developed to implement the automatic control. Optoelectronic laser sensors and laser range scanner were installed in robot for obstacle-navigation control to grasp the overhead ground wires. A novel prototype with careful considerations on mobility was designed to inspect the 500KV power transmission lines. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

  13. METHODICAL APPROACHES TO THE CHOICE OF THE NEW GENERATION OF HIGH-VOLTAGE POWER TRANSMISSION LINE 220 kV OPTIONS

    Directory of Open Access Journals (Sweden)

    POSTOLATI V.M.

    2010-08-01

    Full Text Available The Transmission Power Lines of new generation are described in the article (single- compact, double-circuit compact, double-circuit Controlled Self-compensating High Voltage Transmission Power Lines (CSHVL. Basic principles of creation, design elements and comparative characteristics of the transmission lines of the new generation are described, the advantages of its are showed. Methodical approaches to the choosing of a new generation of transmission lines and facilities management FACTS are formulated. Methodical approaches to the choice of options for transmission lines 220 kV and facilities management are shown.

  14. Attainment of 40.5 pm spatial resolution using 300 kV scanning transmission electron microscope equipped with fifth-order aberration corrector.

    Science.gov (United States)

    Morishita, Shigeyuki; Ishikawa, Ryo; Kohno, Yuji; Sawada, Hidetaka; Shibata, Naoya; Ikuhara, Yuichi

    2018-02-01

    The achievement of a fine electron probe for high-resolution imaging in scanning transmission electron microscopy requires technological developments, especially in electron optics. For this purpose, we developed a microscope with a fifth-order aberration corrector that operates at 300 kV. The contrast flat region in an experimental Ronchigram, which indicates the aberration-free angle, was expanded to 70 mrad. By using a probe with convergence angle of 40 mrad in the scanning transmission electron microscope at 300 kV, we attained the spatial resolution of 40.5 pm, which is the projected interatomic distance between Ga-Ga atomic columns of GaN observed along [212] direction.

  15. Comparison of overhead line lightning performance based on two different tower geometries

    DEFF Research Database (Denmark)

    Ebdrup, Thomas; Olason, Daniel; Bak, Claus Leth

    2014-01-01

    of the substation and transmission line is of great importance as it is a part of the 400 kV backbone between Sweden, Norway, Germany and the offshore wind farms in Horns Rev, Denmark. The new Eagle pylon has been designed with the focus of minimizing the visual impacted of overhead lines. A detailed lightning...... performance analysis of the existing Donau and the new Eagle pylon is therefore important in order to assess the risk of failure. The lightning strike analysis is based on the number of strikes expected to terminate on the line and an investigation of how many of these there may be expected to cause...... better protected from direct stroke than the phase conductors on the Donau pylon. Furthermore with respect to a backflash, the Eagle has a better performance than the Donau pylon. It is therefore concluded that the Eagle has a better lightning performance than the Donau....

  16. 75 FR 75170 - Minnkota Power Cooperative, Inc.: Bemidji to Grand Rapids 230 kV Transmission Line Project

    Science.gov (United States)

    2010-12-02

    ... availability of Record of Decision. SUMMARY: The Rural Utilities Service, hereinafter referred to as RUS and/or the Agency, has issued a Record of Decision (ROD) for the Environmental Impact Statement (EIS) for the... financing to construct the 230 kilovolt (kV) transmission line between the Wilton Substation near Bemidji...

  17. Method of selecting optimum cross arm lengths for a 750 kV transmission line

    Energy Technology Data Exchange (ETDEWEB)

    Aleksandrov, G N; Olorokov, V P

    1965-01-01

    A method is presented, based on both technical and economic considerations, for selecting cross arm lengths for intermediate poles of power transmission lines according to the effects of internal overvoltage, methods from probability theory and mathematical statistics employed. The problem of optimum pole size is considered in terms of the effect of internal overvoltages for a prescribed maximum level of 2.1 PU currently used in the USSR for the design of 750 kV lines.

  18. Switching overvoltage when disconnecting a combined 400 kVcable/overhead line with permanently connected shunt reactor

    DEFF Research Database (Denmark)

    Bak, Claus Leth; Søgaard, Kim

    2008-01-01

    400 kV power system and initiated by Danish TSO Energinet.dk after having measured the voltage of the cable/overhead line after disconnection. A particular decaying dynamic phase voltage containing voltages higher than the voltage before disconnection appeared. A simulation model for the entire system...

  19. Enhancing the reliability of AC transmission networks by using a long distance HVDC-link

    Energy Technology Data Exchange (ETDEWEB)

    Fleckenstein, Marco; Balzer, Gerd; Wasserrab, Andreas; Neumann, Claus [Technische Univ. Darmstadt (Germany). Inst. of Electrical Power and Energy

    2012-07-01

    The absorption of energy from offshore wind farms is a difficult task for Transmission system operators (TSO) in Germany, even if no offshore wind farm is connected directly. The role of the TSOs in the north it is to transport this energy to the south of Germany. The transmission capacities of overhead lines are limited. With the expected rapid expansion of wind farms, this is no longer enough. Thus, the transmission system must be enhanced. One possibility is the installation of an HVDC link from north to south between two main substations in the 380 kV network. Based on a realistic case study, the impact of such a link on the reliability of the entire extra high voltage network is shown. (orig.)

  20. The first 100 Mw Brazil - Argentina interconnection. The design of the 500/525 Kv Rincon de Santa Maria-Garabi-Ita power transmission line; Primeira interconexao 1000 MW Brasil-Argentina. Projeto da LT 500/525 kV Rincon de Santa Maria-Garabi-Ita

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Joao Batista Guimaraes Ferreira da; Guimaraes, Rogerio Peixoto; Menezes, Luciene Oliveira; Amaro, Rania Carla Peixoto [ABB, Belo Horizonte, MG (Brazil)]. E-mail: joao-batista.ferreira@br.abb.com; Silva, Vilson Renato da [Engelineas Consultoria e Projetos Ltda., Porto Alegre, RS (Brazil); Menezes, Ruy Carlos Ramos de [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil); Nolasco, Joao Felix [JFNolasco Consultoria Ltda., Belo Horizonte, MG (Brazil); Bugallo, Francisco [Companhia de Interconexao Energetica (CIEN), Rio de Janeiro, RJ (Brazil)

    2001-07-01

    This document reports the main design aspects and also displays how the implantation challenges had been overcome in relation to the Brazil-Argentina energetic first interconnection, through the frequency converter station in Garabi and the 500 Kv / 50 Hz Rincon de Santa Maria-Garabi transmission line and 500 Kv / 60 Hz Garabi-Ita transmission line, resulting in a total of 490 Kilometers. Firstly, it is presented the basic design characteristics involving the drawing definitions and electrical parameters determination. Afterwards, are presented the transmission line mechanical aspects, as well as the main obtained results. Finally, the project technical viability and the reached benefits had been discussed as well.

  1. Electric transmission technology

    International Nuclear Information System (INIS)

    Shah, K.R.

    1990-01-01

    Electric transmission technology has matured and can transmit bulk power more reliably and economically than the technology 10 years ago.In 1882, Marcel Depres transmitted 15 kW electric power at 2 kV, using a constant direct current; present transmission voltages have risen to ± 600 kV direct current (DC) and 765 kV alternating current (AC), and it is now possible to transmit bulk electric power at voltages as high as ± 1000 kV DC and 1500 kV AC. Affordable computer systems are now available to optimize transmission reliably. New materials have reduced the bulk of insulation for lines and equipment. New conducting materials and configurations have reduced losses in transmission. Advances in line structures and conductor motion, understanding of flashover characteristics of insulators and air-gaps and electrical performance of lines have resulted in more compact urban transmission lines. (author). 15 refs., 7 tabs., 11 figs

  2. Long term investigation of thermal behaviour of 110 kV underground transmission lines in the Belgrade area

    Energy Technology Data Exchange (ETDEWEB)

    Sredojevic, M.R.; Naumov, R.M.; Popovic, D.P. [Nikola Tesla Electrical Engineering Inst., Belgrade (Yugoslavia); Simic, M.D. [Electrical Utility Co., Belgrade (Yugoslavia)

    1997-12-31

    The paper describes the procedure for applying a special cable backfill material, developed and manufactured at the Institute ``Nikola Tesla`` for the thermal stabilisation and reduction of hot spot cable operating temperature, on specific hot spots of 110 kV underground transmission lines in the Belgrade area. The results presented in this paper are an important contribution to the proof of the justification and necessity of defining and introducing in practice new procedures for the thermal stabilisation and reduction of operating temperature of existing, as well as of new, underground transmission cable lines to be built. (author)

  3. Environmental Assessment for Central Power and Light Company`s proposed Military Highway-CFE tie 138/69-kV transmission line project Brownsville, Cameron County, Texas

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    Central Power and Light Company (CPL) intends to upgrade its existing transmission line ties with the Commision Federal de Electricidad (CFE) system in Mexico. CPL currently has a single 69-kilovolt (kV) transmission line in the Brownsville area which connects CPL`s system with the system of CFE. This existing line runs between the Brownsville Switching Station, located on Laredo Road in Brownsville, Cameron County, Texas, and an existing CFE 69-kV line at the Rusteberg Bend of the Rio Grande in Cameron County. Under current conditions of need, the existing 69-kV line does not possess sufficient capability to engage in appropriate power exchanges. Therefore, CPL is proposing to build a new line to link up with CFE. This proposed line would be a double-circuit line, which would (1) continue (on a slightly relocated route) the existing 69-kV tie from CPL`s Brownsville Switching Station to CFE`s facilities, and (2) add a 138-kV tie from the Military Highway Substation, located on Military Highway (US Highway 281), to CFE`s facilities. The proposed 138/69-kV line, which will be constructed and operated by CPL, will be built primarily on steel single-pole structures within an average 60-foot (ft) wide right-of-way (ROW). It will be approximately 6900--9200 ft (1.3--1.7 miles) in length, depending on the alternative route constructed.

  4. Improving the Transmission System Reliability for the 154kV Radial Network Operation

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Jin Boo; Yoo, Myeong Ho; Yoon, Young Beum; Kim, Tae Won [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Lee, Gi Won; Chung, Beom Jin; Jung, Jung Won; Park, Kyu Hyun; Lee, Myung Hee; Kim, Hyun Jong; Kim, Chae Hee [KEYIN CO., (Korea, Republic of)

    1996-12-31

    Analyzing that 154kV radial network current ed operated, we developed Automatic Power Reconfiguration System(APRS) which restore blackout area. It consists of special data acquisition system(DAU) and central monitoring system for reason of protecting currently operating power system. In addition, it communicates using optical communication network for high speed data transmission and accuracy. An Accuracy of operation and stability of the developed system is tested using Real Time Digital Simulator in 3-bus equivalent model system. In An Outage case, our developed system can restore a blackout area in three second. An ability of the restoration of a blackout was verified by simulations. For the field test, the developed system was set up at SINCHON S/S, SESOMUN S/S, SINDANG S/S and MAJANG S/S governed by Seoul Power Transmission Center. If the system reliability is proved for a one year test in real power system, application of the system will be extended to the other substations.

  5. Partial discharge location technique for covered-conductor overhead distribution lines

    Energy Technology Data Exchange (ETDEWEB)

    Isa, M.

    2013-02-01

    In Finland, covered-conductor (CC) overhead lines are commonly used in medium voltage (MV) networks because the loads are widely distributed in the forested terrain. Such parts of the network are exposed to leaning trees which produce partial discharges (PDs) in CC lines. This thesis presents a technique to locate the PD source on CC overhead distribution line networks. The algorithm is developed and tested using a simulated study and experimental measurements. The Electromagnetic Transient Program-Alternative Transient Program (EMTP-ATP) is used to simulate and analyze a three-phase PD monitoring system, while MATLAB is used for post-processing of the high frequency signals which were measured. A Rogowski coil is used as the measuring sensor. A multi-end correlation-based technique for PD location is implemented using the theory of maximum correlation factor in order to find the time difference of arrival (TDOA) between signal arrivals at three synchronized measuring points. The three stages of signal analysis used are: (1) denoising by applying discrete wavelet transform (DWT); (2) extracting the PD features using the absolute or windowed standard deviation (STD) and; (3) locating the PD point. The advantage of this technique is the ability to locate the PD source without the need to know the first arrival time and the propagation velocity of the signals. In addition, the faulty section of the CC line between three measuring points can also be identified based on the degrees of correlation. An experimental analysis is performed to evaluate the PD measurement system performance for PD location on CC overhead lines. The measuring set-up is arranged in a high voltage (HV) laboratory. A multi-end measuring method is chosen as a technique to locate the PD source point on the line. A power transformer 110/20 kV was used to energize the AC voltage up to 11.5 kV/phase (20 kV system). The tests were designed to cover different conditions such as offline and online

  6. Outline of new extra high voltage research equipment at Kumatori research laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Hohki, S; Ikeda, G

    1965-01-01

    Following up the construction in 1939 of an ehv research laboratory, another new research laboratory was established at Kumatori with a ground area of 142,000 square meters. As the first stage of this construction plan, the new research equipment was installed in November 1963 and began operation. The laboratory consists of comprehensive ehv research equipment and facilities relating to atomic energy. The former includes a 6000-kV impulse voltage generator, a 1650-kV alternating current testing transformer, a 300-m overhead transmission test line, a tower strength testing facility, and other various high-power test facilities. Studies on a 400- to 500-kV overhead power transmission system and other new transmission systems are currently being conducted. The details of the construction of the ehv research equipment together with the research policy for future ehv engineering are given.

  7. Comparing Effects of TCR and TSC on MHO Distance Protection Setting in 400 kV Algerian Transmission Line

    Directory of Open Access Journals (Sweden)

    Mohamed ZELLAGUI

    2012-11-01

    Full Text Available This paper presents a study on the performances of distance relays setting in 400 kV in Eastern Algerian transmission networks at Sonelgaz Group (Algerian company of Electrical and Gas compensated by shunt Flexible AC Transmission System (FACTS. The facts are used for controlling transmission voltage, power flow, reactive power, and damping of power system oscillations in high power transfer levels. The effects of SVC devices i.e. Thyristor Controlled Reactor (TCR and the Thyristor Switched Capacitors (TSC insertion, on the total impedance of a transmission line protected by MHO distance relay are investigated. The modified setting zones protections for three forward zones (Z1, Z2 and Z3 have been calculated in order to improve the performances of distance relay protection and prevent circuit breaker nuisance tripping.

  8. Impact of SSSC on Measured Impedance in Single Phase to Ground Fault Condition on 220 kV Transmission Line

    Directory of Open Access Journals (Sweden)

    Mohamed ZELLAGUI

    2012-08-01

    Full Text Available This paper presents and compares the impact of SSSC on measured impedance for single phase to ground fault condition. The presence of Static Synchronous SSSC on a transmission line has a great influence on the ZRelay in distance protection. The protection of the high voltage 220 kV single circuit transmission line in eastern Algerian electrical transmission networks is affected in the case with resistance fault RF. The paper investigate the effect of Static Synchronous Series Compensator (SSSC on the measured impedance (Relay taking into account the distance fault point (n and fault resistance (RF. The resultants simulation is performed in MATLAB software environment.

  9. ON THE NEED TO INCREASE THE RELIABILITY OF LINEAR INSULATORS FOR DISTRIBUTION NETWORKS 10-20 KV

    Directory of Open Access Journals (Sweden)

    Yu. N. Shumilov

    2018-02-01

    Full Text Available Introduction. In Ukraine high voltage overhead distribution lines (OL of class 6 and 10 kV are the most extended. Their total length exceeds 280,000 km. More than 95% of the lines are made on line supports from reinforced concrete racks. On all poles of the overhead line, pin insulators are installed. According to the data of operation experience, up to 60-70% of single-phase earth (SPE faults due to «insulation» occurs on VL supports due to damage to line pin insulators, mainly during the thunderstorm period. Problem. Insufficient reliability of pin insulators leads to interruptions in power supply, accidents on the line, accidents in the area of reinforced concrete poles, where in the case of insulator damages, a long process of SPE occurs. Goal. The purpose of the work is to select the design and develop requirements for new linear insulators of 10-20 kV overhead lines that provide high resistance to lightning overvoltages with direct and inductive effects of lightning. Methodology. The research methodology consists in analyzing operational experience, calculating insulator parameters and laboratory tests. Results. Using statistical data on lightning parameters and data on mechanical loads on insulators, the main dimensions of line post insulators have been determined that will ensure their reliable operation under conditions of intense thunderstorm activity and extreme ice and wind loads. Conclusions. The main technical requirements for line post insulators for 10-20 kV distribution lines were formulated. On the 10 kV OL located in areas with increased thunderstorm activity it is recommended to use line post insulators instead of pin-type ones. On the OL-20 kV it is recommended to use only line post insulators. The use of high-lightning-resistant line post insulators on OL-10-20 kV will significantly increase the electrical safety and reliability of power supply to consumers. Increased by 2-3 times the cost of line post insulators in

  10. Lightning Performance on Overhead Distribution Lines : After Improvement Field Observation

    Directory of Open Access Journals (Sweden)

    Reynaldo Zoro

    2009-11-01

    Full Text Available Two feeders of 20 kV overhead distribution lines which are located in a high lightning density area are chosen to be observed as a field study due to their good lightning performance after improvement of lightning protection system. These two feeders used the new overhead ground wire and new line arrester equipped with lightning counter on the main lines. The significant reduced of lines outages are reported. Study was carried out to observe these improvements by comparing to the other two feeders line which are not improved and not equipped yet with the ground wire and line arrester. These two feeders located in the nearby area. Two cameras were installed to record the trajectory of the lightning strikes on the improved lines. Lightning peak currents are measured using magnetic tape measurement system installed on the grounding lead of lightning arrester. Lightning overvoltage calculations are carried out by using several scenarios based on observation results and historical lightning data derived from lightning detection network. Lightning overvoltages caused by indirect or direct strikes are analyzed to get the lightning performance of the lines. The best scenario was chosen and performance of the lines were improved significantly by installing overhead ground wire and improvement of lightning arrester installation.

  11. Wireless overhead line temperature sensor based on RF cavity resonance

    International Nuclear Information System (INIS)

    Ghafourian, Maryam; Nezhad, Abolghasem Zeidaabadi; Bridges, Greg E; Thomson, Douglas J

    2013-01-01

    The importance of maximizing power transfer through overhead transmission lines necessitates the use of dynamic power control to keep transmission line temperatures within acceptable limits. Excessive conductor operating temperatures lead to an increased sag of the transmission line conductor and may reduce their expected life. In this paper, a passive wireless sensor based on a resonant radio frequency (RF) cavity is presented which can be used to measure overhead transmission line temperature. The temperature sensor does not require a power supply and can be easily clamped to the power line with an antenna attached. Changing temperature causes a change of cavity dimensions and a shift in resonant frequency. The resonant frequency of the cavity can be interrogated wirelessly. This temperature sensor has a resolution of 0.07 °C and can be interrogated from distances greater than 4.5 m. The sensor has a deviation from linearity of less than 2 °C. (paper)

  12. Environmental Assessment and Finding of No Significant Impact: Curecanti-Lost Canyon 230-kV Transmission Line Reroute Project, Montrose County, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    2000-03-20

    The Department of Energy (DOE), Western Area Power Administration (Western) is proposing to reroute a section of the Curecanti-Lost Canyon 230-kilovolt (kV) transmission line, in Montrose County, Colorado. A portion of the transmission line, situated 11 miles southeast of Montrose, Colorado, crosses Waterdog Peak, an area of significant geologic surface activity, which is causing the transmission line's lattice steel towers to shift. This increases stress to structure hardware and conductors, and poses a threat to the integrity of the transmission system. Western proposes to relocate the lattice steel towers and line to a more geologically stable area. The existing section of transmission line and the proposed relocation route cross Bureau of Land Management and private land holdings.

  13. Life Cycle Assessment on a 765 kV Venezuelan Transmission System

    International Nuclear Information System (INIS)

    Wang, Wenlu; Tremouille, Gilles; Beroual, Abderrahmane; Bessede, Jean-Luc

    2011-03-01

    The demand to preserve the environment and form a sustainable development is greatly increasing in the recent decades all over the world, and this environmental concern is also merged in electrical power industry, resulting in many eco-design approaches in T and D industries. As a method of eco-design, Life Cycle Assessment (LCA) is a systematic tool that enables the assessment of the environmental impacts of a product or service throughout its entire life cycle, i.e. raw material production, manufacture, distribution, use and disposal including all intervening transportation steps necessary or caused by the product's existence. In T and D industries, LCA has been done for a lot of products individually, in order to see one product's environmental impacts and to seek for ways of improving its environmental performance. This eco-design for product approach is a rather well-developed trend, however, as only a single electrical product cannot provide the electrical power to users, electrical system consists of a huge number of components, in order to investigate system's environmental profile, the entire environmental profiles of different composing products has to be integrated systematically, that is to say, a system approach is needed. Under this philosophy, in this paper, an LCA using SimaPro (one kind of LCA software) is conducted on a whole Venezuelan 765 kV AC transmission system, which transmits 8000 MW hydro-electrical power through 760 km to this country's load centers, with total 7 substations, i.e. one sending end, 2 intermediate substations and 4 receiving ends. This LCA includes both transmission lines and substations, and then the environmental impacts of the whole transmission system are investigated. (authors)

  14. Flatiron-Erie 115kV transmission line project, Larimer, Weld and Boulder Counties, Colorado

    International Nuclear Information System (INIS)

    1993-05-01

    Western Area Power Administration (Western) proposes to uprate its existing 115-kV Flatiron-Erie transmission line. The line is located in Larimer, Weld and Boulder Counties, Colorado, and passes through the City of Longmont. The line connects Flatiron Substation and several of the substations supplying Longmont. It is a single circuit 115-kV line, 31.5 miles long, and was built in 1950-51 on a 75-foot wide right-of-way (ROW) using wood H-frame structures. Western proposes to build 27 new structures along the line, to replace or modify 45 of the existing structures and to remote 11 of them. Many of these additions and changes would involve structures that are approximately 5 to 15 feet taller than the existing ones. The existing conductors and ground wires would remain in place. The purpose of these actions would be to allow the power carrying capability of the line to be increased and to replace deteriorating/structural members. Western would be the sole participant in the proposed project. This report gives an analysis of the study area environment and the development of alternative routes. An assessment is presented of the impacts of the primary alternative routes. The environmental consequences of this project are addressed

  15. Assessment of Lightning Shielding Performance of a 400 kV Double-Circuit Fully Composite Transmission Line Pylon

    DEFF Research Database (Denmark)

    Jahangiri, Tohid; Bak, Claus Leth; Silva, Filipe Miguel Faria da

    2016-01-01

    -quality insulation sections. Thus, the configuration of phase conductors on the cross-arm is in the form of diagonal and differs from other widely used configurations in overhead transmission lines i.e. horizontal, delta and vertical configurations. Unlike traditional steel lattice towers, the composite pylon does...... not provide access to ground potential due to its non-conductive materials. Therefore, the lightning shielding of pylon and conductors requires a ground potential access to shield wires by utilizing a ground cable inside the hollow cross-arm and pylon body. Efficient design of a lightning shielding system...

  16. Improvements in the computation of balances and localization of commercial losses of electric energy in 0.38-kV networks

    International Nuclear Information System (INIS)

    Vorotnitskii, V. Z.; Zaslonov, S. V.; Lysyuk, S. S.

    2006-01-01

    An example of four 0.38-kV overhead distribution lines fed from a 10/0.4-kV transformer substation of the Grodno Electrical Networks (Belarus') and supplying electricity to a cottage area is used for analyzing energy balances and commercial losses in the networks. It is shown that the reliability of such analysis can be ensured by the use of modern software and electronic energy meters recording a retrospective of half-hourly intervals of active and reactive electric energy

  17. Potential environmental effects of 765-kV transmission lines: views before the New York State Public Service Commission, Cases 26529 and 26559, 1976-1978

    Energy Technology Data Exchange (ETDEWEB)

    Scott-Walton, B.; Clark, K. M.; Holt, B. R.; Jones, D. C.; Kaplan, S. D.; Krebs, J. S.; Polson, P.; Shepherd, R. A.; Young, J. R.

    1979-11-01

    Testimony given before the New York Public Service Commission in two recent cases on the potential environmental effects of 765-kV overhead ac transmission lines is reviewed. The testimony focused on the potential effects of audible noise, on the potential biological effects of the electromagnetic fields, on the potential for electric shocks to people who touch vehicles parked under the proposed lines, on the potential effects of the electromagnetic fields on electronic cardiac pacemakers, and on potential effects of ozone produced by corona discharge from the lines. The testimony fully explored these questions; however, it did not resolve all of them. The testimony indicates potential impacts from the audible noise and from the electrostatic shocks that people can receive when they touch a large vehicle parked under the lines. The testimony also indicates that certain cardiac pacemaker and lead combinations may, under certain circumstances, undergo reversion to a fixed rate of pacing in the presence of the fields under the lines, but that little risk to cardiac patients results except possibly for those patients for whom competition between the heart's own rate and the pacemaker rate presents a health risk. The testimony fails to demonstrate biological hazards from the field; further research is necessary to understand better the effects of the fields on biological systems. The testimony indicates that ozone produced by the lines will not significantly affect the environment.

  18. Structural health monitoring of compression connectors for overhead transmission lines

    Science.gov (United States)

    Wang, Hong; Wang, Jy-An John; Swindeman, Joseph P.; Ren, Fei; Chan, John

    2017-04-01

    Two-stage aluminum conductor steel-reinforced (ACSR) compression connectors are extensively used in US overhead transmission lines. The connectors are made by crimping a steel sleeve onto a steel core and an aluminum sleeve over electrical conducting aluminum strands. The connectors are designed to operate at temperatures up to 125°C, but their performance is increasingly degrading because of overloading of lines. Currently, electric utilities conduct routine line inspections using thermal and electrical measurements, but these methods do not provide information about the structural integrity of connectors. In this work, structural health monitoring (SHM) of compression connectors was studied using electromechanical impedance (EMI) analysis. Lead zirconate titanate (PZT)-5A was identified as a smart material for SHM. A flexible high-temperature bonding layer was used to address challenges in PZT integration due to a significant difference in the coefficients of thermal expansion of PZT and the aluminum substrate. The steel joint on the steel core was investigated because it is responsible for the ultimate tensile strength of the connector. Tensile testing was used to induce structural damage to the joint, or steel core pullout, and thermal cycling introduced additional structural perturbations. EMI measurements were conducted between the tests. The root mean square deviation (RMSD) of EMI was identified as a damage index. The use of steel joints has been shown to enable SHM under simulated conditions. The EMI signature is sensitive to variations in structural conditions. RMSD can be correlated to the structural health of a connector and has potential for use in the SHM and structural integrity evaluation.

  19. Power cables with extruded insulation and their accessories for rated voltages from 1 kV (Um = 1,2 kV) up to 30 kV (Um = 36 kV) : Part 2: cables for rated voltages from 6 kV (Um = 7,2 kV) up to 30 kV (Um = 36 kV)

    CERN Document Server

    International Electrotechnical Commission. Geneva

    2005-01-01

    Power cables with extruded insulation and their accessories for rated voltages from 1 kV (Um = 1,2 kV) up to 30 kV (Um = 36 kV) : Part 2: cables for rated voltages from 6 kV (Um = 7,2 kV) up to 30 kV (Um = 36 kV)

  20. Analyzing the Health Risks Resulting from Extending the 400kV High Voltage Transmission Lines on the Human

    Directory of Open Access Journals (Sweden)

    Mohammed Hassan Dervish

    2018-01-01

    Full Text Available Although it is difficult to imagine life without electricity, there are compiling confirmations show thatexposure to magnetic fields correlated electricity and radio frequencies pose magnificent hazards to human health. The most economist method to transfer electricity from power generation stations to users is by measures of high power transmission lines, buoyed by big transmission towers. The cables laced between the towers radiate magnetic and electric fields. In this research study, the magnetic field at ground level under 400 kV network lines extended in residential places have been conducted in two ways, mathematical calculation and practical measurement then the obtained results analyzed and compared with the international standards reference values. the reason of chose this type of transmission line is frequently using. The results indicate that they fall within the safe limiter commended by the WorldHealth Organization. the strength of radiation increasing with high of sea level and moisture ratiobecause of air ionization.

  1. Distance Protection Impedance Measurement for Inhomogeneous Multiple-Circuit 400/150 kV Transmission Lines with Shared Towers

    DEFF Research Database (Denmark)

    Bak, Claus Leth; Sigurbjörnsson, Ragnar; Bukh, Bjarne

    2016-01-01

    are interconnected in a simple way but via transformers and infeed from remaining parts of the network. Distance relay measured fault loop impedance shows wide ranges of variations for both phase-phase loops as well as phase-earth loops. No simple relations exist. Simulation models can be used to study fault loop...... impedance for combined faults and thereby shed light on relay trips. This study uses actual fault records, analytical method and PSCAD simulation studies to analyse combined faults in an existing 400 and 150 kV transmission line owned by Danish TSO Energinet.dk. The results clearly show that an accurate...

  2. 77 FR 12282 - Notice Soliciting Scoping Comments

    Science.gov (United States)

    2012-02-29

    ...-megawatt (MW) horizontal Kaplan bulb turbine/generator unit; (4) a 2,300-foot-long, 13.2-kilovolt (kV... Kaplan bulb turbine/generator unit; (4) a 3.0 mile-long, 34.5-kV overhead transmission line leading from... the downstream Pool No. 4 of the Red River; (3) a 28.1-MW horizontal Kaplan bulb turbine/generator...

  3. Transmission Line Ampacity Improvements of AltaLink Wind Plant Overhead Tie-Lines Using Weather-Based Dynamic Line Rating

    Energy Technology Data Exchange (ETDEWEB)

    Bhattarai, Bishnu P.; Gentle, Jake P.; Hill, Porter; McJunkin, Tim; Myers, Kurt S.; Abbound, Alex; Renwick, Rodger; Hengst, David

    2017-07-01

    Abstract—Overhead transmission lines (TLs) are conventionally given seasonal ratings based on conservative environmental assumptions. Such an approach often results in underutilization of the line ampacity as the worst conditions prevail only for a short period over a year/season. We presents dynamic line rating (DLR) as an enabling smart grid technology that adaptively computes ratings of TLs based on local weather conditions to utilize additional headroom of existing lines. In particular, general line ampacity state solver utilizes measured weather data for computing the real-time thermal rating of the TLs. The performance of the presented method is demonstrated from a field study of DLR technology implementation on four TL segments at AltaLink, Canada. The performance is evaluated and quantified by comparing the existing static and proposed dynamic line ratings, and the potential benefits of DLR for enhanced transmission assets utilization. For the given line segments, the proposed DLR results in real-time ratings above the seasonal static ratings for most of the time; up to 95.1% of the time, with a mean increase of 72% over static rating.

  4. Fort Peck-Wolf Point transmission line project, Montana

    International Nuclear Information System (INIS)

    1992-01-01

    The primary objective of the project is to replace the existing 36-mile Fort Peck-Wolf Point transmission line which has reached the end of its useful service life. Presently, the overall condition of this existing section of the 47-year-old line is poor. Frequent repairs have been required because of the absence of overhead ground wires. The continued maintenance of the line will become more expensive and customer interruptions will persist because of the damage due to lightning. The expense of replacing shell rotted poles, and the concern for the safety of the maintenance personnel because of hazards caused by severe shell rot are also of primary importance. The operational and maintenance problems coupled with power system simulation studies, demonstrate the need for improvements to the Wolf Point area to serve area loads. Western's Wolf Point Substation is an important point of interconnection for the power output from the Fort Peck Dam to area loads as far away as Williston, North Dakota. The proposed transmission line replacement would assure that there will continue to be reliable transmission capacity available to serve area electrical loads, as well as provide a reliable second high-voltage transmission path from the Fort Peck generation to back-up a loss of the Fort Peck-Wolf Point 115-kV Line No. 1

  5. APPLICATION OF SSSC TO THE 330kV NIGERIAN ...

    African Journals Online (AJOL)

    HOD

    2,3 DEPARTMENT OF ELECTRONIC AND ELECTRICAL ENGR., FEDERAL POLYTECHNIC EDE, ... Longitudinal power systems of Nigerian 330 kV transmission network have steady-state ..... C tr ller ” Unpublish Master Thesis Submitted to.

  6. Low overhead and nonlinear-tolerant adaptive zero-guard-interval CO-OFDM.

    Science.gov (United States)

    Wang, Wei; Zhuge, Qunbi; Gao, Yuliang; Qiu, Meng; Morsy-Osman, Mohamed; Chagnon, Mathieu; Xu, Xian; Plant, David V

    2014-07-28

    We propose an adaptive channel estimation (CE) method for zero-guard-interval (ZGI) coherent optical (CO)-OFDM systems, and demonstrate its performance in a single channel 28 Gbaud polarization-division multiplexed ZGI CO-OFDM experiment with only 1% OFDM processing overhead. We systematically investigate its robustness against various transmission impairments including residual chromatic dispersion, polarization-mode dispersion, state of polarization rotation, sampling frequency offset and fiber nonlinearity. Both experimental and numerical results show that the adaptive CE-aided ZGI CO-OFDM is highly robust against these transmission impairments in fiber optical transmission systems.

  7. The electrically silent Kv6.4 subunit confers hyperpolarized gating charge movement in Kv2.1/Kv6.4 heterotetrameric channels.

    Directory of Open Access Journals (Sweden)

    Elke Bocksteins

    Full Text Available The voltage-gated K(+ (Kv channel subunit Kv6.4 does not form functional homotetrameric channels but co-assembles with Kv2.1 to form functional Kv2.1/Kv6.4 heterotetrameric channels. Compared to Kv2.1 homotetramers, Kv6.4 exerts a ~40 mV hyperpolarizing shift in the voltage-dependence of Kv2.1/Kv6.4 channel inactivation, without a significant effect on activation gating. However, the underlying mechanism of this Kv6.4-induced modulation of Kv2.1 channel inactivation, and whether the Kv6.4 subunit participates in the voltage-dependent gating of heterotetrameric channels is not well understood. Here we report distinct gating charge movement of Kv2.1/Kv6.4 heterotetrameric channels, compared to Kv2.1 homotetramers, as revealed by gating current recordings from mammalian cells expressing these channels. The gating charge movement of Kv2.1/Kv6.4 heterotetrameric channels displayed an extra component around the physiological K(+ equilibrium potential, characterized by a second sigmoidal relationship of the voltage-dependence of gating charge movement. This distinct gating charge displacement reflects movement of the Kv6.4 voltage-sensing domain and has a voltage-dependency that matches the hyperpolarizing shift in Kv2.1/Kv6.4 channel inactivation. These results provide a mechanistic basis for the modulation of Kv2.1 channel inactivation gating kinetics by silent Kv6.4 subunits.

  8. Overhead-Aware-Best-Fit (OABF) Resource Allocation Algorithm for Minimizing VM Launching Overhead

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hao [IIT; Garzoglio, Gabriele [Fermilab; Ren, Shangping [IIT, Chicago; Timm, Steven [Fermilab; Noh, Seo Young [KISTI, Daejeon

    2014-11-11

    FermiCloud is a private cloud developed in Fermi National Accelerator Laboratory to provide elastic and on-demand resources for different scientific research experiments. The design goal of the FermiCloud is to automatically allocate resources for different scientific applications so that the QoS required by these applications is met and the operational cost of the FermiCloud is minimized. Our earlier research shows that VM launching overhead has large variations. If such variations are not taken into consideration when making resource allocation decisions, it may lead to poor performance and resource waste. In this paper, we show how we may use an VM launching overhead reference model to minimize VM launching overhead. In particular, we first present a training algorithm that automatically tunes a given refer- ence model to accurately reflect FermiCloud environment. Based on the tuned reference model for virtual machine launching overhead, we develop an overhead-aware-best-fit resource allocation algorithm that decides where and when to allocate resources so that the average virtual machine launching overhead is minimized. The experimental results indicate that the developed overhead-aware-best-fit resource allocation algorithm can significantly improved the VM launching time when large number of VMs are simultaneously launched.

  9. 78 FR 69844 - Alaska Village Electric Cooperative, Inc.; Notice of Application Tendered for Filing With the...

    Science.gov (United States)

    2013-11-21

    ... CEO, AVEC, 4831 Eagle Street, Anchorage, AK 99503; Telephone (907) 561-1818. i. FERC Contact: Mary... system in Old Harbor. Transmission Line A 6,500-foot-long, 12.47-kV, 3-phase overhead power line will be...

  10. A low-latency, low-overhead encoder for data transmission in the ATLAS Liquid Argon Calorimeter trigger upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Le [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Li, Xiaoting [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Gong, Datao, E-mail: dgong@mail.smu.edu [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Chen, Jinghong [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77004 (United States); Deng, Binwei [School of Electric and Electronic Information Engineering, Hubei Polytechnic University, Huangshi, Hubei 435003 (China); Fan, Qingjun; Feng, Yulang [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77004 (United States); Guo, Di [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); He, Huiqin [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Shenzhen Polytechnic, Shenzhen 518055 (China); Hou, Suen [Institute of Physics, Academia Sinica, Nangang 11529, Taipei, Taiwan (China); Huang, Guangming, E-mail: gmhuang@phy.ccnu.edu.cn [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Liu, Chonghan; Liu, Tiankuan [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Sun, Xiangming [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Tang, Yuxuan [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77004 (United States); Teng, Ping-Kun [Institute of Physics, Academia Sinica, Nangang 11529, Taipei, Taiwan (China); and others

    2016-09-21

    In this paper, we present the design and test results of an encoder integrated circuit for the ATLAS Liquid Argon Calorimeter trigger upgrade. The encoder implements a low-latency and low-overhead line code called LOCic. The encoder operates at 320 MHz with a latency of no greater than 21 ns. The overhead of the encoder is 14.3%. The encoder is an important block of the transmitter ASIC LOCx2, which is prototyped with a commercial 0.25 μm Silicon-on-Sapphire CMOS technology and packaged in a 100-pin QFN package. - Highlights: • We present the design and test results of an encoder integrated circuit for the ATLAS Liquid Argon Calorimeter trigger upgrade. • The encoder implements a low-latency and low-overhead line code called LOCic. The encoder operates at 320 MHz with a latency of no greater than 21 ns. The overhead of the encoder is 14.3%. • The encoder is an important block of the transmitter ASIC LOCx2, which is prototyped with a commercial 0.25 μm Silicon-on-Sapphire CMOS technology for radiation-tolerance and packaged in a 100-pin QFN package.

  11. UHV A.C. transmission: Technology and prospects

    International Nuclear Information System (INIS)

    Cauzillo, B.A.; Manzoni, G.; Nicolini, P.

    1992-04-01

    At the beginning of the 70's, UHV transmission was regarded as imminent in many countries in view of the expected concentration of generating units (possibly of the nuclear type and grouped together in a few large plants, each of several GW), and research projects were therefore launched in the U.S.A., Canada, Italy, Japan, USSR, etc. Nowadays, the expected introduction of UHV transmission seems remote due to the slowdown in electricity growth and to the tendency towards distributed generation. Nevertheless, there are exceptions: the 1,200 kV 2,400 km-long transmission system in operation in Siberia-Kazahkstan-Urals, and the 1,100 kV 200 km double-circuit line under construction in Japan (which will, however, be operated at 500 kV up to the end of the century). In addition, in Italy, the research programme of a 1000 kV project has now been completed and a 1,050 kV pilot plant is under construction in Tuscany, consisting of a short 1,050kV line and a 420/1,050 kV 1,200 MVA substation. The technology of UHV AC transmission has therefore been proved effective and may represent an available option for the power systems of the next century. From the power system planning point-of-view, UHV's favourable characteristics lie in the possibility of transmitting large amount of power, of the order of 5 GW per circuit, with lower costs, reduced losses, and less land occupation than in the case of EHV lines

  12. Single-phase AutoReClosure ARC failure on 400 kV combinedcable/overhead line with permanently connected shunt reactor

    DEFF Research Database (Denmark)

    Bak, Claus Leth; Søgaard, Kim

    2008-01-01

    consisting of overhead lines, crossbonded cable sections and shunt reactor has been created in PSCAD/EMTDC and verified against measurements with good results. Main focus has been put on the likelihood of having a successful single-phase autoreclosure ARC in such a combined cable/OHL line....

  13. 735 kV circuit breakers for ehv

    Energy Technology Data Exchange (ETDEWEB)

    1966-01-01

    French manufacturers have been studying the design of high and extra high voltage circuit breakers for several years. The two techniques they used were the low volume oil and the air pressure technique. These have permitted the development of a type gear capable of solving problems all over the world as they arose following the development of electrical energy transmission at extra high voltage as well as high short circuit power. Today, the air pressure solution is used in new constructions such as the 735 kV transmission network in Canada.

  14. Thermometer by optical fiber for ampacity studies in overhead transmission lines; Termometro a fibra optica para estudo da ampacidade em linhas de transmissao aereas

    Energy Technology Data Exchange (ETDEWEB)

    Valente, L.C.G.; Kawase, L.R.; Silva Filho, J.I. da; Silva, J.M.M. da [Centro de Pesquisas de Energia Eletrica, Rio de Janeiro, RJ (Brazil); Igarashi, A.Y. [Universidade Federal, Rio de Janeiro, RJ (Brazil)

    1995-12-31

    This article suggests the utilization of thermometers constructed from optical fibers technology in overhead power transmission lines. This will help the studies in progress about the electric power systems ampacity. It also presents the advantages of using optical fibers instead of conventional thermometers. As an example, the fact that the optical fibers are dielectric and make possible the remote monitoring. It is also shown a possibility of introducing such measuring system in electric junctions where OPGW cables are used 4 refs., 4 figs.; e-mail: liliana at fis.puc-rio.br

  15. Scale model test on a novel 400 kV double-circuit composite pylon

    DEFF Research Database (Denmark)

    Wang, Qian; Bak, Claus Leth; Silva, Filipe Miguel Faria da

    This paper investigates lightning shielding performance of a novel 400 kV double-circuit composite pylon, with the method of scale model test. Lightning strikes to overhead lines were simulated by long-gap discharges between a high voltage electrode with an impulse voltage and equivalent conductors...... around the pylon is discussed. Combined test results and striking distance equation in electro-geometric model, the approximate maximum lightning current that can lead to shielding failure is calculated. Test results verify that the unusual negative shielding angle of - 60° in the composite pylon meets...... requirement and the shielding wires provide acceptable protection from lightning strikes....

  16. A Design of a 345-kV Electric Power Transmission Line Interlinking Ramu and Rouna Grids in Papua New Guinea

    Directory of Open Access Journals (Sweden)

    Sakato Francis

    2017-01-01

    Full Text Available According to PNG Power Limited (PPL, Papua New Guinea’s peak power demand is expected to increase from 210 MW in 2012 to 347 MW in 2026. Under the current state of the power sector in Papua New Guinea (PNG, it is critical to implement measures to cope with the increasing power demand to promote investment, economic growth, and ultimately to achieve poverty reduction through economic growth. One of the solutions identified to improve the reliability of PNG power systems and thus to meet the demand is to interconnect the major grids in the country so that the loads could be shared among them. This project embarks in designing a 345-kV electric power transmission line to interlink the Ramu and Rouna power grids of Papua New Guinea. The design is done by analysing all the necessary aspects of the transmission lines with in-depth calculations performed using MATHCAD software. This design is the basis for extra-high voltage (EHV transmission network in anticipation for the power generation and demand growth in PNG.

  17. Draft Environmental Impact Statement: BPA/Puget Power Northwest Washington Transmission Project

    International Nuclear Information System (INIS)

    1993-11-01

    Bonneville Power Administration (BPS) and Puget Sound Power ampersand Light (Puget Power) propose to upgrade the existing high-voltage transmission system in the Whatcom and Skagit County area between the towns of Custer and Sedro Woolley, including within the city of Bellingham starting in 1995. The upgrades of the interconnected 230,000 volt (230-kV) and 115-kV systems are needed to increase the reliability of the local transmission system and to increase the import capacity on a nearby US-Canada 500-kV intertie by about 850 megawatts (MW). The increase in north-south transfer capability would be shared by BPA and Puget Power (about 425 MW each). Other actions would include replacement of an existing BPA 230-kV single-circuit, wood-pole H-frame transmission line with a lattice-steel double-circuit line; an existing Puget Power 115-kV single wood-pole transmission line rebuild, two short 115-kV Puget Power lines added at BPA's Bellingham Substation; and improvements made at existing BPA and Puget Power substations

  18. An Annotated Bibliography of High-Voltage Direct-Current Transmission and Flexible AC Transmission (FACTS) Devices, 1991-1993.

    Energy Technology Data Exchange (ETDEWEB)

    Litzenberger, Wayne; Lava, Val

    1994-08-01

    References are contained for HVDC systems, converter stations and components, overhead transmission lines, cable transmission, system design and operations, simulation of high voltage direct current systems, high-voltage direct current installations, and flexible AC transmission system (FACTS).

  19. Transmission delays in hardware clock synchronization

    Science.gov (United States)

    Shin, Kang G.; Ramanathan, P.

    1988-01-01

    Various methods, both with software and hardware, have been proposed to synchronize a set of physical clocks in a system. Software methods are very flexible and economical but suffer an excessive time overhead, whereas hardware methods require no time overhead but are unable to handle transmission delays in clock signals. The effects of nonzero transmission delays in synchronization have been studied extensively in the communication area in the absence of malicious or Byzantine faults. The authors show that it is easy to incorporate the ideas from the communication area into the existing hardware clock synchronization algorithms to take into account the presence of both malicious faults and nonzero transmission delays.

  20. Low voltage 80 KV to 125 KV electron processors

    International Nuclear Information System (INIS)

    Lauppi, U.V.

    1999-01-01

    The classic electron beam technology made use of accelerating energies in the voltage range of 300 to 800 kV. The first EB processors - built for the curing of coatings - operated at 300 kV. The products to be treated were thicker than a simple layer of coating with thicknesses up to 100g and more. It was only in the beginning of the 1970's that industrial EB processors with accelerating voltages below 300 kV appeared on the market. Our company developed the first commercial electron accelerator without a beam scanner. The new EB machine featured a linear cathode, emitting a shower or 'curtain' of electrons over the full width of the product. These units were much smaller than anv previous EB processors and dedicated to the curing of coatings and other thin layers. ESI's first EB units operated with accelerating voltages between 150 and 200 kV. In 1993 ESI announced the introduction of a new generation of Electrocure. EB processors operating at 120 kV, and in 1998, at the RadTech North America '98 Conference in Chicago, the introduction of an 80 kV electron beam processor under the designation Microbeam LV

  1. Overhead Crane Computer Model

    Science.gov (United States)

    Enin, S. S.; Omelchenko, E. Y.; Fomin, N. V.; Beliy, A. V.

    2018-03-01

    The paper has a description of a computer model of an overhead crane system. The designed overhead crane system consists of hoisting, trolley and crane mechanisms as well as a payload two-axis system. With the help of the differential equation of specified mechanisms movement derived through Lagrange equation of the II kind, it is possible to build an overhead crane computer model. The computer model was obtained using Matlab software. Transients of coordinate, linear speed and motor torque of trolley and crane mechanism systems were simulated. In addition, transients of payload swaying were obtained with respect to the vertical axis. A trajectory of the trolley mechanism with simultaneous operation with the crane mechanism is represented in the paper as well as a two-axis trajectory of payload. The designed computer model of an overhead crane is a great means for studying positioning control and anti-sway control systems.

  2. 735 kV air-blast circuit breakers for Hydro Quebec

    Energy Technology Data Exchange (ETDEWEB)

    Lindstrom, I

    1966-01-01

    In 1962 the Quebec Hydro-Electric Commission started the development of aproject for utilizing water power in Manicouagan and Outardes, two rivers some 350 miles northeast of the city of Montreal on the left bank of the St. Lawrence estuary. The project involved the transmission of power at 735 kV ac from Manicouagan and Outardes to the heavy and growing load centers of Quebec and Montreal. The total amount of energy to be transmitted in the final stage is about 6,000 MW. The project involved the need of considerable quantities of apparatus for 735 kV, such as transformers, reactors, lightning arrestors, circuit-breakers, and disconnectors. Since the supply of the major part of the 735 kV circuit-breakers, altogether 14 three-pole units, was awarded to ASEA in Sweden, a short presentation of these airblast circuit-breakers is presented.

  3. Seasonal Patterns of Melatonin, Cortisol, and Progesterone Secretion in Female Lambs Raised Beneath a 500-kV Transmission Line.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jack M.

    1992-06-01

    Although several kinds of biological effects of electric and magnetic fields have been reported from laboratory studies, few have been independently replicated. When this study was being planned, the suppression of nighttime melatonin in rodents was thought to represent one of the strongest known effects of these fields. The effect had been replicated by a single laboratory for 60-Hz electric fields, and by multiple laboratories for d-c magnetic fields. The primary objective of this study was to determine whether the effect of electric and magnetic fields on melatonin would also occur in sheep exposed to a high voltage transmission line. The specific hypothesis tested by this experiment was as follows: The electrical environment produced by a 60-Hz, 500-kV transmission line causes a depression in nocturnal melatonin in chronically exposed female lambs. This may mimic effects of pinealectomy or constant long-day photoperiods, thus delaying the onset of reproductive cycles. Results of the study do not provide evidence to support the hypothesis. Melatonin concentrations in the sheep exposed to the transmission line showed the normal pattern of low daytime and high nighttime serum levels. As compared to the control group, there were no statistically significant group differences in the mean amplitude, phase, or duration of the nighttime melatonin elevation.

  4. Asbestos fiber release from the brake pads of overhead industrial cranes.

    Science.gov (United States)

    Spencer, J W; Plisko, M J; Balzer, J L

    1999-06-01

    The purpose of this evaluation was to determine the actual contribution of airborne asbestos fibers to the work environment from the operation of overhead cranes and hoists that use asbestos composition brake pads. The evaluation was conducted in a working manufacturing facility. Other potential sources of asbestos were accounted for by visual inspection and background air monitoring. An overhead crane assembly comprised of a trolley and two hoists was employed for this study. The crane was operated for two consecutive eight-hour shifts representative of a heavy-duty cycle. Forty-four personal and area air samples were collected during the assessment. Asbestos fibers were analyzed for by phase contrast (NIOSH 7400), and transmission electron (NIOSH 7402) microscopy methods. Eight-hour time-weighted average (TWA) asbestos fiber concentrations ranged from cranes.

  5. Step-by-step application methodology in practical KEPCO 22.9kV bus-bar system

    International Nuclear Information System (INIS)

    Yoon, Jae-young; Lee, Seung-yeol

    2010-01-01

    With the increase of power demand and the progress of power industry deregulation, the transmission and distribution systems will have more complicated problems by the influence of curtailing investment and the NIMBY phenomena in overall power systems. [1-2] It is expected that the route length per MW demand of South Korea will decrease gradually from 0.6[C-km/MW] to 0.53[C-km/MW] in 2010.[3] This comes up to a real serious problem from system planning and operation viewpoints. HTS technologies related to power system have properties to solve these complex transmission and distribution constraints, especially for metropolitan area, in the future. As the HTS technology has developed, the HTS cable technology can be the most effective alternative to solve the future expected power network constraints. This paper describes the application methodology of developing 22.9kV HTS cable by CAST for practical distribution system. 22.9kV HTS cable under development with step-by-step application methodology can substitute the existing and planning conventional 154kV cable.[4-5] If this scheme is applied, part of downtown 154kV substation of metropolitan city such as Seoul can be changed into 22.9kV switching station. Additionally, it can give huge economic, environmental benefits to all of the concerned authorities.

  6. Single channel and WDM transmission of 28 Gbaud zero-guard-interval CO-OFDM.

    Science.gov (United States)

    Zhuge, Qunbi; Morsy-Osman, Mohamed; Mousa-Pasandi, Mohammad E; Xu, Xian; Chagnon, Mathieu; El-Sahn, Ziad A; Chen, Chen; Plant, David V

    2012-12-10

    We report on the experimental demonstration of single channel 28 Gbaud QPSK and 16-QAM zero-guard-interval (ZGI) CO-OFDM transmission with only 1.34% overhead for OFDM processing. The achieved transmission distance is 5120 km for QPSK assuming a 7% forward error correction (FEC) overhead, and 1280 km for 16-QAM assuming a 20% FEC overhead. We also demonstrate the improved tolerance of ZGI CO-OFDM to residual inter-symbol interference compared to reduced-guard-interval (RGI) CO-OFDM. In addition, we report an 8-channel wavelength-division multiplexing (WDM) transmission of 28 Gbaud QPSK ZGI CO-OFDM signals over 4160 km.

  7. Controlled Compact High Voltage Power Lines

    Directory of Open Access Journals (Sweden)

    Postolati V.

    2016-04-01

    Full Text Available Nowadays modern overhead transmission lines (OHL constructions having several significant differences from conventional ones are being used in power grids more and more widely. Implementation of compact overhead lines equipped with FACTS devices, including phase angle regulator settings (compact controlled OHL, appears to be one of the most effective ways of power grid development. Compact controlled AC HV OHL represent a new generation of power transmission lines embodying recent advanced achievements in design solutions, including towers and insulation, together with interconnection schemes and control systems. Results of comprehensive research and development in relation to 110–500kV compact controlled power transmission lines together with theoretical basis, substantiation, and methodological approaches to their practical application are presented in the present paper.

  8. 78 FR 43224 - Notice of Availability of the Final Environmental Impact Statement for the Proposed Sun Valley to...

    Science.gov (United States)

    2013-07-19

    ....XXX; AZA35079] Notice of Availability of the Final Environmental Impact Statement for the Proposed Sun... Land Management (BLM) has prepared a Final Environmental Impact Statement (EIS) for the proposed Sun..., operate, and maintain a 500/230-kV overhead transmission line from the Sun Valley Substation to the Morgan...

  9. Transmission policy in Alberta and Bill 50

    International Nuclear Information System (INIS)

    Church, J.; Rosehart, W.; MacCormack, J.

    2009-01-01

    Plans developed by the Alberta Electric System Operator (AESO) have determined that Alberta's electrical transmission system needs to be expanded. However, there are complex issues that must be considered in order to assess the nature and extent of the needed expansion. Various new amendments to the system were proposed in the Alberta government's Bill 50, including the construction of new transmission lines; the installation of a double circuit 500 kV alternating current line between Edmonton and the Gibbons-Redwater region; the construction of a new 240 kV substation in southeast Calgary; and the installation of 2 single circuit 500 kV alternating current lines between Edmonton and Fort McMurray. This study provided a review of the institutional framework instituted by the government's transmission policy and compared the costs and benefits of 2 large capacity high voltage DC (HVDC) transmission lines proposed for the Edmonton-Calgary corridor relative to the various other transmission system amendment suggestions. An evaluation of Alberta's proposed regulatory process under Bill 50 was also conducted. Results of the study indicated that the addition of the HVDC lines is an inefficient response to concerns over adequate supply and reliability. 72 refs., 18 tabs.

  10. The fallacy of the overhead quick fix.

    Science.gov (United States)

    Blaxill, M F; Hout, T M

    1991-01-01

    Facing pressure from a few large, low-cost competitors, Thornton, an old-guard specialty-equipment manufacturer, fought back by eliminating overhead. Over two-years, it outsourced components and consolidated operations. But instead of cutting overhead, it added more and became still more uncompetitive. Thornton is not alone in either its predicament or its failed reaction. Many large manufacturing companies are finding themselves at a cost disadvantage in markets they have dominated for years. One reason is excessive overhead structures, the result of an unchecked buildup of indirect employees needed to control rising organizational complexity. Another reason is the emergence of the "robust" competitor, comparable in size and product scope but able to produce at a lower unit overhead cost. Data collected from more than 100 manufacturing plants worldwide illustrate the differences between overhead cost structures of bureaucratic, niche, and robust companies. The gulf between these groups highlights the need for action by bureaucratic companies, and, in some cases, by niche companies. But high-overhead companies are doomed if they cut overhead out of the system either by outsourcing or downsizing. If they expect to retain their size and also become more cost competitive, they must rethink their manufacturing systems. Well-designed and well-controlled processes mean higher product quality, faster cycle time, improved flexibility, and lower overhead costs. Sustainable overhead reduction means a commitment to continuous improvement. This includes segmenting, mapping, and measuring existing processes and then working to improve them.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Random Shift and XOR of Unequal-sized Packets (RaSOR) to Shave off Transmission Overhead

    DEFF Research Database (Denmark)

    Taghouti, Maroua; Roetter, Daniel Enrique Lucani; Fitzek, Frank Hanns Paul

    2017-01-01

    We propose the design of a novel coding scheme of unequal-sized packets. Unlike the conventional wisdom that consists of brute-force zero-padding in Random Linear Network Coding (RLNC), we exploit this heterogeneity to shave off this trailing overhead and transmit considerably less coded packets....

  12. Analysis of behaviour of overhead telecommunications or electric lines illuminated by a nuclear electromagnetic pulse: limitations of use for the transmission line theory

    International Nuclear Information System (INIS)

    Scotto, M.; Jecko, B.

    1987-01-01

    The illumination of overhead lines by a nuclear electromagnetic pulse (NEMP) in presence of a perfectly conducting ground gives rise to a scattering problem leading to phenomena both studied here in time and frequency domains. This problem is resolved with the help of an integral equation established in space-time domain and making possible (without approximation) the determination of the time dependence of the current induced on each point of the wire structure. Moreover, the passage in frequency domain allows to express a transfer function defined in one point of the excited line, pointing out its spectral characteristics. Results clearly show the insufficiency of the classic transmission line theory concealing some phenomena which are described here and for which an interpretation is proposed [fr

  13. Smart patch integration development of compression connector structural health monitoring in overhead transmission lines

    Science.gov (United States)

    Wang, Hong; Wang, Jy-An J.; Ren, Fei; Chan, John

    2016-04-01

    Integration of smart patches into full-tension splice connectors in overhead power transmission lines was investigated. Lead zirconate titanate (PZT) -5A was used as a smart material and an aluminum beam was used as a host structure. Negative electrode termination was examined by using copper adhesive tape and direct bonding methods. Various commercial adhesives were studied for PZT integration onto the host structure. Aluminum beam specimens with integrated PZT smart patches were tested under thermal cycling at a temperature of 125°C, which is the higher-end temperature experienced by in-service aluminum conductor steel-reinforced cables. Electromechanical impedance (EMI) measurements were conducted at room temperature, and the root mean square deviation (RMSD) of the conductance signals was used to analyze the EMI data. It has been shown that the negative electrode method has an important effect on the performance of the integrated PZT. The PZT displayed more susceptibility to cracking when copper tape was used than when direct bonding was used. The reliability of PZT in direct bonding depended on the adhesives used in bonding layers. Although a hard alumina-based adhesive can lead to cracking of the PZT, a high-temperature epoxy with adequate flexibility, such as Duralco 4538D, can provide the desired performance under target thermal cycling conditions. The RMSD parameter can characterize conductance signatures effectively. It also was demonstrated that RMSD can be used to quantify the fatigue of the PZT integration system, although RMSD is used primarily as a damage index in monitoring structural health.

  14. Analysis of disturbances in the 15 kV traction power network by means of simulation calculations and tests; Analyse von Stoerungen im 15-kV-Bahnenergienetz durch Simulationsrechnungen und Versuche

    Energy Technology Data Exchange (ETDEWEB)

    Aeberhard, Martin; Basler, Egon [SBB AG, Zollikofen (Switzerland). Infrastruktur Energie

    2013-06-15

    Being one of the most important rail junctions of Switzerland, Olten is powered by a substation the 132 kV feeder of which features a number of structural weaknesses. Simulations were used to analyse the effects of electrical equipment failures in this substation on train operation, the nearby 15 kV overhead line system and the loads adjacent substations are subjected to. By considering all risks, a critical case of train operation with different load scenarios was investigated. The article includes a comparison between simulated and measured data and presents the conclusions that were drawn from the actions taken in respect of the future system design. (orig.)

  15. Systems for protection and automation of distribution electric networks 22 kv

    International Nuclear Information System (INIS)

    Horak, M.

    2012-01-01

    This article deals with the new concept of fault location in overhead and cable 22 kV distribution systems, which are operated by ZSE Distribucia, a.s.. In the past the localisation of faults was a demanding and lengthy procedure, because the electric protection indicated only the affected output feeder. The exact fault point was then localised by manipulation in the field and by test switching in the power line where the fault took place. The current development of electric facilities and sharp fall in prices give use the possibility to broadly apply the simple digital metering devices equipped with the electric protection function. Once these devices are positioned densely along the individual power lines of the network, it is possible to localise the failure position quite exactly and electricity supply can be quickly restored. (Authors)

  16. Actual practical considerations about overhead line engineering. Planning of overhead lines is booming; Aktuelle praktische Betrachtung der Freileitungstechnik. Freileitungsplanung boomt

    Energy Technology Data Exchange (ETDEWEB)

    Bueckner, W.F.

    2007-04-30

    The power breakdowns we encountered in March 2006 due to extreme weather conditions and in November 2006 due to overload of overhead lines made overhead line techniques more interesting. After pausing for decades, technical development and investments for overhead lines in Germany become necessary again, meaning reconstructions and new constructions worth several millions of investment. An additional reason for this is given by the Federal Government's request for the construction of new power plants and overhead lines as well as by the energy plan of the EU-Commission. The power supplier have begun planning already. These plans require new and economical overhead lines. Proposals and practical examples are shown in the following article.

  17. Power losses in electrical networks depending on weather conditions

    International Nuclear Information System (INIS)

    Zhelezko, Yu. S.; Kostyushko, V. A.; Krylov, S. V.; Nikiforov, E. P.; Savchenko, O. V.; Timashova, L. V.; Solomonik, E. A.

    2005-01-01

    Specific power losses to corona and to leakage currents over overhead insulators are presented for 110 - 750-kV transmission lines with different phase design and pole types for different weather conditions. Consumption of electric energy for ice melting on conductors of various cross sections is evaluated. Meteorological data of 1372 weather stations in Russia are processed for a period of 10 years. The territory of the country is divided into 7 regions with approximately homogeneous weather conditions. Specific power losses to corona and leakage currents over overhead insulators are presented for every region

  18. Fiscal 1999 research result report on energy and environment technology demonstration research support project (International joint demonstration research project). Improvement of long-distant power transmission efficiency and reliability, and its environmental impact assessment; 1999 nendo chokyori soden hoshiki ni kansuru soden koritsu to soden shinraido no kojo oyobi kankyo eno eikyo hyoka seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Japan-Russia international joint research was made on overhead ultrahigh-voltage DC power transmission lines for transmission loss reduction and reliability improvement, and an optimum international power supply cable system, considering energy saving and environment conservation. Using the European-Russian DC power transmission line of {+-}500kV and 4GW as a model, comparison was made between a model using Russian round strands and glass insulators and a model using Japanese low-loss wires and insulators. As for improvement of the reliability in cold districts, Russian design techniques for tower structure and ice loading were reasonable to counteract galloping oscillation and ice load. In evaluation and selection of optimum underground and marine cables, study was made on cable specifications using the Turkey-Russia power transmission route as a model. The environmental assessment result of these cables showed that XLPE cable under development is optimum. (NEDO)

  19. Why transmission is still the critical link

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, V. [ESBI Alberta Ltd., Calgary, AB (Canada)

    2002-07-01

    This paper describes the important role that transmission plays in the competitive electric power industry in North America and around the world. In the past several years the transmission sector has experienced a lack of investment, congestion on transmission networks, merchant transmission development, and the creation of Regional Transmission Organizations (RTOs). The transmission grid is central to the reliability of the entire electricity system. It also plays a vital role in promoting efficient markets in electricity. The author discusses the consequences of inadequate investment to this critical link within the power industry. He also discusses how much investment is needed, and the challenges and solutions to building an infrastructure. The integrated electric system and the electricity industry in Alberta is very different from those in the United Sates, but the issues facing the industry are the same. The challenge is the sharp increase in the number of system access requests by new generators combined with the difficulties in siting new transmission lines. There are 17,000 km of transmission lines in Alberta, at voltages ranging from 69 kV to 500 kV. There are also connections between neighbouring provinces. The transmission lines have a value of C$1.5 billion. Since there have been no major additions to the transmission grid since the mid-1980s, significant investments in the coming years will have a disproportionate impact on the cost of transmission. Two merchant transmission projects have been proposed. The first will enhance transfer of electricity between Alberta and Saskatchewan by 150 MW, and the second is proposed to be a 1,500 MW, 500 kV DC line from the Fort McMurray area to the Pacific Northwest. 5 figs.

  20. Kv1 channels and neural processing in vestibular calyx afferents

    Directory of Open Access Journals (Sweden)

    Frances L Meredith

    2015-06-01

    Full Text Available Potassium-selective ion channels are important for accurate transmission of signals from auditory and vestibular sensory end organs to their targets in the central nervous system. During different gravity conditions, astronauts experience altered input signals from the peripheral vestibular system resulting in sensorimotor dysfunction. Adaptation to altered sensory input occurs, but it is not explicitly known whether this involves synaptic modifications within the vestibular epithelia. Future investigations of such potential plasticity require a better understanding of the electrophysiological mechanisms underlying the known heterogeneity of afferent discharge under normal conditions. This study advances this understanding by examining the role of the Kv1 potassium channel family in mediating action potentials in specialized vestibular afferent calyx endings in the gerbil crista and utricle. Pharmacological agents selective for different sub-types of Kv1 channels were tested on membrane responses in whole cell recordings in the crista. Kv1 channels sensitive to α-dendrotoxin and dendrotoxin-K were found to prevail in the central regions, whereas K+ channels sensitive to margatoxin, which blocks Kv1.3 and 1.6 channels, were more prominent in peripheral regions. Margatoxin-sensitive currents showed voltage-dependent inactivation. Dendrotoxin-sensitive currents showed no inactivation and dampened excitability in calyces in central neuroepithelial regions. The differential distribution of Kv1 potassium channels in vestibular afferents supports their importance in accurately relaying gravitational and head movement signals through specialized lines to the central nervous system. Pharmacological modulation of specific groups of K+ channels could help alleviate vestibular dysfunction on earth and in space.

  1. Kv1 channels and neural processing in vestibular calyx afferents.

    Science.gov (United States)

    Meredith, Frances L; Kirk, Matthew E; Rennie, Katherine J

    2015-01-01

    Potassium-selective ion channels are important for accurate transmission of signals from auditory and vestibular sensory end organs to their targets in the central nervous system. During different gravity conditions, astronauts experience altered input signals from the peripheral vestibular system resulting in sensorimotor dysfunction. Adaptation to altered sensory input occurs, but it is not explicitly known whether this involves synaptic modifications within the vestibular epithelia. Future investigations of such potential plasticity require a better understanding of the electrophysiological mechanisms underlying the known heterogeneity of afferent discharge under normal conditions. This study advances this understanding by examining the role of the Kv1 potassium channel family in mediating action potentials in specialized vestibular afferent calyx endings in the gerbil crista and utricle. Pharmacological agents selective for different sub-types of Kv1 channels were tested on membrane responses in whole cell recordings in the crista. Kv1 channels sensitive to α-dendrotoxin and dendrotoxin-K were found to prevail in the central regions, whereas K(+) channels sensitive to margatoxin, which blocks Kv1.3 and 1.6 channels, were more prominent in peripheral regions. Margatoxin-sensitive currents showed voltage-dependent inactivation. Dendrotoxin-sensitive currents showed no inactivation and dampened excitability in calyces in central neuroepithelial regions. The differential distribution of Kv1 potassium channels in vestibular afferents supports their importance in accurately relaying gravitational and head movement signals through specialized lines to the central nervous system. Pharmacological modulation of specific groups of K(+) channels could help alleviate vestibular dysfunction on earth and in space.

  2. Kv1.1 knock-in ataxic mice exhibit spontaneous myokymic activity exacerbated by fatigue, ischemia and low temperature.

    Science.gov (United States)

    Brunetti, Orazio; Imbrici, Paola; Botti, Fabio Massimo; Pettorossi, Vito Enrico; D'Adamo, Maria Cristina; Valentino, Mario; Zammit, Christian; Mora, Marina; Gibertini, Sara; Di Giovanni, Giuseppe; Muscat, Richard; Pessia, Mauro

    2012-09-01

    Episodic ataxia type 1 (EA1) is an autosomal dominant neurological disorder characterized by myokymia and attacks of ataxic gait often precipitated by stress. Several genetic mutations have been identified in the Shaker-like K(+) channel Kv1.1 (KCNA1) of EA1 individuals, including V408A, which result in remarkable channel dysfunction. By inserting the heterozygous V408A, mutation in one Kv1.1 allele, a mouse model of EA1 has been generated (Kv1.1(V408A/+)). Here, we investigated the neuromuscular transmission of Kv1.1(V408A/+) ataxic mice and their susceptibility to physiologically relevant stressors. By using in vivo preparations of lateral gastrocnemius (LG) nerve-muscle from Kv1.1(+/+) and Kv1.1(V408A/+) mice, we show that the mutant animals exhibit spontaneous myokymic discharges consisting of repeated singlets, duplets or multiplets, despite motor nerve axotomy. Two-photon laser scanning microscopy from the motor nerve, ex vivo, revealed spontaneous Ca(2+) signals that occurred abnormally only in preparations dissected from Kv1.1(V408A/+) mice. Spontaneous bursting activity, as well as that evoked by sciatic nerve stimulation, was exacerbated by muscle fatigue, ischemia and low temperatures. These stressors also increased the amplitude of compound muscle action potential. Such abnormal neuromuscular transmission did not alter fiber type composition, neuromuscular junction and vascularization of LG muscle, analyzed by light and electron microscopy. Taken together these findings provide direct evidence that identifies the motor nerve as an important generator of myokymic activity, that dysfunction of Kv1.1 channels alters Ca(2+) homeostasis in motor axons, and also strongly suggest that muscle fatigue contributes more than PNS fatigue to exacerbate the myokymia/neuromyotonia phenotype. More broadly, this study points out that juxtaparanodal K(+) channels composed of Kv1.1 subunits exert an important role in dampening the excitability of motor nerve axons during

  3. Wood pole overhead lines

    CERN Document Server

    Wareing, Brian

    2005-01-01

    This new book concentrates on the mechanical aspects of distribution wood pole lines, including live line working, environmental influences, climate change and international standards. Other topics include statutory requirements, safety, profiling, traditional and probabilistic design, weather loads, bare and covered conductors, different types of overhead systems, conductor choice, construction and maintenance. A section has also been devoted to the topic of lightning, which is one of the major sources of faults on overhead lines. The book focuses on the effects of this problem and the strate

  4. Development of a 400 kV 80 mA Cockcroft-Walton power supply and 12 kW isolation transformer systems for neutron generators

    Science.gov (United States)

    Lu, X.; Chen, S.; Zhang, Y.; Huang, Z.; Ma, Z.; Yao, Z.

    2017-06-01

    A 400 kV 80 mA Cockcroft-Walton power supply driven by 2.5 kHz frequency, and 12 kW isolation transformer systems are developed for an intense DD/DT neutron generator. The design, construction, and testing of the high voltage (HV) power supply and isolation transformer systems are detailed reported. The structure of step-up transformers can make the potential distribution uniform, and auxiliary coils of the isolation transformers can improve the power transmission efficiency significantly. The testing results show that the HV power supply can reach 400 kV, and the isolation transformer systems can withstand 400 kV voltages and its power transmission efficiency is about 98.1%.

  5. 30 CFR 56.16014 - Operator-carrying overhead cranes.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Operator-carrying overhead cranes. 56.16014 Section 56.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 56.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  6. 30 CFR 57.16014 - Operator-carrying overhead cranes.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Operator-carrying overhead cranes. 57.16014 Section 57.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 57.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  7. Complexity Quantification for Overhead Transmission Line Emergency Repair Scheme via a Graph Entropy Method Improved with Petri Net and AHP Weighting Method

    Directory of Open Access Journals (Sweden)

    Jing Zhou

    2014-01-01

    Full Text Available According to the characteristics of emergency repair in overhead transmission line accidents, a complexity quantification method for emergency repair scheme is proposed based on the entropy method in software engineering, which is improved by using group AHP (analytical hierarchical process method and Petri net. Firstly, information structure chart model and process control flowchart model could be built by Petri net. Then impact factors on complexity of emergency repair scheme could be quantified into corresponding entropy values, respectively. Finally, by using group AHP method, weight coefficient of each entropy value would be given before calculating the overall entropy value for the whole emergency repair scheme. By comparing group AHP weighting method with average weighting method, experiment results for the former showed a stronger correlation between quantified entropy values of complexity and the actual consumed time in repair, which indicates that this new method is more valid.

  8. AC transmission, with very high voltages and the 750 kV line

    Energy Technology Data Exchange (ETDEWEB)

    Bocker, H

    1964-01-01

    The economic case for adoption of extra-high voltages for transmitting electric power over distances of the order of 1000 km is discussed. Some special technical developments for solving the problems attached to such high voltages are briefly discussed, particularly in the fields of switching and transients suppression. The first 750-kV projects in Canada and Russia are mentioned. Equipment, e.g., bushings, transformers, etc., operating at such voltages are illustrated.

  9. [Shoulder injuries in overhead sports].

    Science.gov (United States)

    Wörtler, K

    2010-05-01

    Overhead sport places great demands on the shoulder joint. Shoulder pain in overhead athletes and throwers can in the majority of cases be attributed to lesions resulting from chronic overuse of tendons and capsuloligamentous structures or to sequels of microinstability and secondary impingement. Due to its great impact on therapeutic decisions, imaging in athletes with unclear shoulder pain is a challenge. In this connection, magnetic resonance (MR) arthrography represents the cross-sectional imaging modality of first choice, as it allows depiction and exclusion of pathologic alterations of all relevant joint structures with sufficient confidence.This article reviews the biomechanical and clinical aspects and MR arthrographic features of the most common shoulder pathologies in overhead athletes, including biceps tendinopathy, superior labral anterior-posterior (SLAP) lesions, rotator cuff lesions, as well as extrinsic and intrinsic impingement syndromes.

  10. Ground-Wave Propagation Effects on Transmission Lines through Error Images

    Directory of Open Access Journals (Sweden)

    Uribe-Campos Felipe Alejandro

    2014-07-01

    Full Text Available Electromagnetic transient calculation of overhead transmission lines is strongly influenced by the natural resistivity of the ground. This varies from 1-10K (Ω·m depending on several media factors and on the physical composition of the ground. The accuracy on the calculation of a system transient response depends in part in the ground return model, which should consider the line geometry, the electrical resistivity and the frequency dependence of the power source. Up to date, there are only a few reports on the specialized literature about analyzing the effects produced by the presence of an imperfectly conducting ground of transmission lines in a transient state. A broad range analysis of three of the most often used ground-return models for calculating electromagnetic transients of overhead transmission lines is performed in this paper. The behavior of modal propagation in ground is analyzed here into effects of first and second order. Finally, a numerical tool based on relative error images is proposed in this paper as an aid for the analyst engineer to estimate the incurred error by using approximate ground-return models when calculating transients of overhead transmission lines.

  11. Transmission and capacity pricing and constraints

    International Nuclear Information System (INIS)

    Fusco, M.

    1999-01-01

    A series of overhead viewgraphs accompanied this presentation which discussed the following issues regarding the North American electric power industry: (1) capacity pricing transmission constraints, (2) nature of transmission constraints, (3) consequences of transmission constraints, and (4) prices as market evidence. Some solutions suggested for pricing constraints included the development of contingent contracts, back-up power in supply regions, and new line capacity construction. 8 tabs., 20 figs

  12. Mitochondrial ultrastructure and glucose signaling pathways attributed to the Kv1.3 ion channel

    Directory of Open Access Journals (Sweden)

    Christopher P. Kovach

    2016-05-01

    Full Text Available Gene-targeted deletion of the potassium channel Kv1.3 (Kv1.3-/- results in ‘Super-smeller’ mice with a sensory phenotype that includes an increased olfactory ability linked to changes in olfactory circuitry, increased abundance of olfactory cilia, and increased expression of odorant receptors and the G-protein, Golf. Kv1.3-/- mice also have a metabolic phenotype including lower body weight and decreased adiposity, increased total energy expenditure (TEE, increased locomotor activity, and resistance to both diet- and genetic-induced obesity. We explored two cellular aspects to elucidate the mechanism by which loss of Kv1.3 channel in the olfactory bulb (OB may enhance glucose utilization and metabolic rate. First, using in situ hybridization we find that Kv1.3 and the insulin-dependent glucose transporter type 4 (GLUT4 is co-localized to the mitral cell layer of the OB. Disruption of Kv1.3 conduction via construction of a pore mutation (W386F Kv1.3 was sufficient to independently translocate GLUT4 to the plasma membrane in HEK 293 cells. Because olfactory sensory perception and the maintenance of action potential firing frequency by mitral cells of the OB is highly energy demanding and Kv1.3 is also expressed in mitochondria, we next explored the structure of this organelle in mitral cells. We challenged wildtype (WT and Kv1.3-/- male mice with a moderately high-fat diet (MHF, 31.8 % kcal fat for 4 months and then examined OB ultrastructure using transmission microscopy. In WT mice, mitochondria were significantly enlarged following diet-induced obesity (DIO and there were fewer mitochondria, likely due to mitophagy. Interestingly, mitochondria were significantly smaller in Kv1.3-/- mice compared with that of WT mice. Similar to their metabolic resistance to DIO, the Kv1.3-/- mice had unchanged mitochondria in terms of cross sectional area and abundance following a challenge with modified diet. We are very interested to understand how

  13. Seasonal Patterns of Melatonin, Cortisol, and Progesterone Secretion in Female Lambs Raised Beneath a 500-KV Transmission Line

    Science.gov (United States)

    Lee, Jack Monroe, Jr.

    There is ongoing controversy about the possibility of adverse biological effects from environmental exposures to electric and magnetic fields. These fields are produced by all electrical equipment and appliances including electrical transmission lines. The objective of this environmental science study was to investigate the possible effects of a high voltage transmission line on domestic sheep (Ovis aries L.), a species that can often be found near such lines. The study was primarily designed to determine whether a specific effect of electric and magnetic fields found in laboratory animals also occurs in livestock under natural environmental conditions. The effect is the ability of fields, at levels found in the environment, to significantly depress the normally high nocturnal concentrations of the pineal hormone-melatonin. Ten female Suffolk lambs were penned for 10 months directly beneath a 500-kV transmission line near Estacada, Oregon. Ten other lambs of the same type were penned in a control area away from the transmission line where electric and magnetic fields were at ambient levels. Serum melatonin was analyzed by radioimmunoassay (RIA) from 6618 blood samples collected at 0.5 to 3-hour intervals over eight 48-hour periods. Serum progesterone was analyzed by RIA from blood samples collected twice weekly. Serum cortisol was also assayed by RIA from the blood samples collected during the 48-hour samples. Results showed that lambs in both the control and line groups had the typical pattern of melatonin secretion consisting of low daytime and high nighttime serum concentrations. There were no statistically significant differences between groups in melatonin levels, or in the phase or duration of the nighttime melatonin elevation. Age at puberty and number of reproductive cycles also did not differ between groups. Serum cortisol showed a circadian rhythm with highest concentrations during the day. There were, however, no differences in cortisol concentrations

  14. Shoulder injuries in overhead sports

    International Nuclear Information System (INIS)

    Woertler, K.

    2010-01-01

    Overhead sport places great demands on the shoulder joint. Shoulder pain in overhead athletes and throwers can in the majority of cases be attributed to lesions resulting from chronic overuse of tendons and capsuloligamentous structures or to sequels of microinstability and secondary impingement. Due to its great impact on therapeutic decisions, imaging in athletes with unclear shoulder pain is a challenge. In this connection, magnetic resonance (MR) arthrography represents the cross-sectional imaging modality of first choice, as it allows depiction and exclusion of pathologic alterations of all relevant joint structures with sufficient confidence. This article reviews the biomechanical and clinical aspects and MR arthrographic features of the most common shoulder pathologies in overhead athletes, including biceps tendinopathy, superior labral anterior-posterior (SLAP) lesions, rotator cuff lesions, as well as extrinsic and intrinsic impingement syndromes. (orig.) [de

  15. Snow accretion on overhead wires

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, Y. [Meteorological Research Inst. for Technology Co. Ltd., Tokyo (Japan); Tachizaki, S.; Sudo, N. [Tohoku Electric Power Co. Ltd., Miyagi (Japan)

    2005-07-01

    Wet snow accretion can cause extensive damage to transmission systems. This paper reviewed some of the difficulties faced by researchers in the study of wet snow accretion on overhead lines in Japan. The study of snow accretion phenomena is complicated by the range of phase changes in water. Snowflakes produced in an upper atmospheric layer with a temperature below freezing do not melt when they go through a lower atmospheric layer with a temperature above freezing, but are in a mixed state of solid and liquid due to the latent heat of melting. The complicated properties of water make studies of snow accretion difficult, as well as the fact that snow changes its physical properties rapidly, due to the effects of ambient temperature, rainfall, and solar radiation. The adhesive forces that cause snow accretion include freezing; bonding through freezing; sintering; condensation and freezing of vapor in the air; mechanical intertwining of snowflakes; capillary action due to liquids; coherent forces between ice particles and water formed through the metamorphosis of snowflakes. In addition to these complexities, differences in laboratory room environments and natural snow environments can also pose difficulties for researchers. Equations describing the relationship between the density of accreted snow and the meteorological parameters involved were presented, as well as empirical equations which suggested that snow accretion efficiency has a dependency on air temperature. An empirical model for estimating snow loads in Japan was outlined, as well as various experiments observing show shedding. Correlations for wet snow accretion included precipitation intensity; duration of precipitation; air temperature; wind speed and wind direction in relation to the overhead line. Issues concerning topography and wet snow accretion were reviewed. It was concluded that studies of snow accretion will benefit by the collection of data in each matrix of the relevant parameters. 12 refs

  16. Functional analysis of Kv1.2 and paddle chimera Kv channels in planar lipid bilayers

    Science.gov (United States)

    Tao, Xiao; MacKinnon, Roderick

    2010-01-01

    Summary Voltage-dependent K+ channels play key roles in shaping electrical signaling in both excitable as well as non-excitable cells. These channels open and close in response to the voltage changes across the cell membrane. Many studies have been carried out in order to understand the voltage sensing mechanism. Our laboratory recently determined the atomic structures of a mammalian voltage-dependent K+ channel Kv1.2 and a mutant of Kv1.2 named the ‘paddle-chimera’ channel, in which the voltage sensor paddle was transferred from Kv2.1 to Kv1.2. These two structures provide atomic descriptions of voltage-dependent channels with unprecedented clarity. Until now the functional integrity of these two channels biosynthesized in yeast cells have not been assessed. Here we report the electrophysiological and pharmacological properties of Kv1.2 and the paddle chimera channels in planar lipid bilayers. We demonstrate that Pichia yeast produce ‘normally functioning’ mammalian voltage-dependent K+ channels with qualitatively similar features to the Shaker K+ channel in the absence of the N-terminal inactivation gate, and that the paddle chimera mutant channel functions as well as Kv1.2. We find, however, that in several respects the Kv1.2 channel exhibits functional properties that are distinct from Kv1.2 channels reported in the literature. PMID:18638484

  17. Effects of electromagnetic field of 33 and 275 kV influences on ...

    African Journals Online (AJOL)

    The effects of electromagnetic fields (EMF) from 33 and 275 kV high voltage transmission line on biochemical and antioxidant system changes in mustard leaf (Brassica chinensis) were investigated under field condition. Mustard leaves were exposed to EMF from power lines at distances of 0, 3, 6, 9, 10, 12, 15, 18, 20, 21, ...

  18. Communication Characteristics of Faulted Overhead High Voltage Power Lines at Low Radio Frequencies

    Directory of Open Access Journals (Sweden)

    Nermin Suljanović

    2017-11-01

    Full Text Available This paper derives a model of high-voltage overhead power line under fault conditions at low radio frequencies. The derived model is essential for design of communication systems to reliably transfer information over high voltage power lines. In addition, the model can also benefit advanced systems for power-line fault detection and classification exploiting the phenomenon of changed conditions on faulted power line, resulting in change of low radio frequency signal propagation. The methodology used in the paper is based on the multiconductor system analysis and propagation of electromagnetic waves over the power lines. The model for the high voltage power line under normal operation is validated using actual measurements obtained on 400 kV power line. The proposed model of faulted power lines extends the validated power-line model under normal operation. Simulation results are provided for typical power line faults and typical fault locations. Results clearly indicate sensitivity of power-line frequency response on different fault types.

  19. Distance Protection of Cross-Bonded Transmission Cable-Systems

    DEFF Research Database (Denmark)

    Bak, Claus Leth; F. Jensen, Christian

    2014-01-01

    In this paper the problems of protecting a cross-bonded cable system using distance protection are analysed. The combination of the desire to expand the high voltage transmission grid and the public's opinion towards new installations of overhead lines (OHL), more and more transmission cable syst...

  20. Evaluation of Instrumentation and Dynamic Thermal Ratings for Overhead Lines

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, A. [New York Power Authority, White Plains, NY (United States)

    2013-01-31

    In 2010, a project was initiated through a partnership between the Department of Energy (DOE) and the New York Power Authority (NYPA) to evaluate EPRI's rating technology and instrumentation that can be used to monitor the thermal states of transmission lines and provide the required real-time data for real-time rating calculations. The project included the installation and maintenance of various instruments at three 230 kV line sites in northern New York. The instruments were monitored, and data collection and rating calculations were performed for about a three year period.

  1. Throughput, Energy and Overhead of Multicast Device-to-Device Communications with Network Coded Cooperation

    DEFF Research Database (Denmark)

    Hernandez, Nestor; Heide, Janus; Roetter, Daniel Enrique Lucani

    2017-01-01

    , this assumes that the throughput gains and energy savings in multicasting are much larger between devices than the base station to the receivers. However, current mobile networks suffer from many different issues varying the performance in data rates, which calls into question these assumptions. Therefore......, a first objective of this work is to assess the operating regions where employing cooperation results in higher throughput and/or energy savings. We consider multicast scenarios with network coded mechanisms employing Random Linear Network Coding (RLNC). However, although RLNC is good for low amount...... of transmissions in multicast, it has an inherent overhead from extreme high or low field related caveats. Thus, as a second objective, we review and propose the application of new network codes that posses low overhead for multicasting, by having a short representation and low dependence probability. We provide...

  2. Superiority of the practical method to theory: Diagnose of service life of ropes in overhead transmission grids; Praktische Methode der Theorie ueberlegen: Diagnose der Lebensdauer von Freileitungsseilen

    Energy Technology Data Exchange (ETDEWEB)

    Brueckner, W.F.

    2005-02-07

    In designing overhead transmission lines, cable tension is of prior importance. High tension means shorter life unless vibration dampers are installed. On the other hand, higher tension will reduce the overall cost to an optimum level. The author presents experience and measured vibration sensitivities. (orig.) [German] Beim Entwurf von Freileitungen ist die Zugspannung der Seile von besonderer Bedeutung. Erhoehte Seilzugspannungen verringern die Lebensdauer der Seile, soweit die Schwingungsgefahr nicht durch geeignete Schwingungsdaempfer vermieden wird. Mit erhoehter Seilzugspannung verringern sich auch die Kosten der gesamten Freileitung bis zur optimalen Grenze, die von den Kosten je km fuer verschiedene Spannweiten zu bestimmen ist. Der Verfasser beschreibt Erfahrungen ueber die gemessene Schwingungsgefaehrdung der Seile. (orig.)

  3. Computer-based mechanical design of overhead lines

    Science.gov (United States)

    Rusinaru, D.; Bratu, C.; Dinu, R. C.; Manescu, L. G.

    2016-02-01

    Beside the performance, the safety level according to the actual standards is a compulsory condition for distribution grids’ operation. Some of the measures leading to improvement of the overhead lines reliability ask for installations’ modernization. The constraints imposed to the new lines components refer to the technical aspects as thermal stress or voltage drop, and look for economic efficiency, too. The mechanical sizing of the overhead lines is after all an optimization problem. More precisely, the task in designing of the overhead line profile is to size poles, cross-arms and stays and locate poles along a line route so that the total costs of the line's structure to be minimized and the technical and safety constraints to be fulfilled.The authors present in this paper an application for the Computer-Based Mechanical Design of the Overhead Lines and the features of the corresponding Visual Basic program, adjusted to the distribution lines. The constraints of the optimization problem are adjusted to the existing weather and loading conditions of Romania. The outputs of the software application for mechanical design of overhead lines are: the list of components chosen for the line: poles, cross-arms, stays; the list of conductor tension and forces for each pole, cross-arm and stay for different weather conditions; the line profile drawings.The main features of the mechanical overhead lines design software are interactivity, local optimization function and high-level user-interface

  4. Mechanosensitive gating of Kv channels.

    Directory of Open Access Journals (Sweden)

    Catherine E Morris

    Full Text Available K-selective voltage-gated channels (Kv are multi-conformation bilayer-embedded proteins whose mechanosensitive (MS Popen(V implies that at least one conformational transition requires the restructuring of the channel-bilayer interface. Unlike Morris and colleagues, who attributed MS-Kv responses to a cooperative V-dependent closed-closed expansion↔compaction transition near the open state, Mackinnon and colleagues invoke expansion during a V-independent closed↔open transition. With increasing membrane tension, they suggest, the closed↔open equilibrium constant, L, can increase >100-fold, thereby taking steady-state Popen from 0→1; "exquisite sensitivity to small…mechanical perturbations", they state, makes a Kv "as much a mechanosensitive…as…a voltage-dependent channel". Devised to explain successive gK(V curves in excised patches where tension spontaneously increased until lysis, their L-based model falters in part because of an overlooked IK feature; with recovery from slow inactivation factored in, their g(V datasets are fully explained by the earlier model (a MS V-dependent closed-closed transition, invariant L≥4. An L-based MS-Kv predicts neither known Kv time courses nor the distinctive MS responses of Kv-ILT. It predicts Kv densities (hence gating charge per V-sensor several-fold different from established values. If opening depended on elevated tension (L-based model, standard gK(V operation would be compromised by animal cells' membrane flaccidity. A MS V-dependent transition is, by contrast, unproblematic on all counts. Since these issues bear directly on recent findings that mechanically-modulated Kv channels subtly tune pain-related excitability in peripheral mechanoreceptor neurons we undertook excitability modeling (evoked action potentials. Kvs with MS V-dependent closed-closed transitions produce nuanced mechanically-modulated excitability whereas an L-based MS-Kv yields extreme, possibly excessive

  5. Remote sensing for industrial applications in the energy business: digital territorial data integration for planning of overhead power transmission lines (OHTLs)

    Science.gov (United States)

    Terrazzino, Alfonso; Volponi, Silvia; Borgogno Mondino, Enrico

    2001-12-01

    An investigation has been carried out, concerning remote sensing techniques, in order to assess their potential application to the energy system business: the most interesting results concern a new approach, based on digital data from remote sensing, to infrastructures with a large territorial distribution: in particular OverHead Transmission Lines, for the high voltage transmission and distribution of electricity on large distances. Remote sensing could in principle be applied to all the phases of the system lifetime, from planning to design, to construction, management, monitoring and maintenance. In this article, a remote sensing based approach is presented, targeted to the line planning: optimization of OHTLs path and layout, according to different parameters (technical, environmental and industrial). Planning new OHTLs is of particular interest in emerging markets, where typically the cartography is missing or available only on low accuracy scale (1:50.000 and lower), often not updated. Multi- spectral images can be used to generate thematic maps of the region of interest for the planning (soil coverage). Digital Elevation Models (DEMs), allow the planners to easily access the morphologic information of the surface. Other auxiliary information from local laws, environmental instances, international (IEC) standards can be integrated in order to perform an accurate optimized path choice and preliminary spotting of the OHTLs. This operation is carried out by an ABB proprietary optimization algorithm: the output is a preliminary path that bests fits the optimization parameters of the line in a life cycle approach.

  6. Corona performance of a compact 230-kV line

    International Nuclear Information System (INIS)

    Chartier, V.L.; Blair, D.E.

    1994-01-01

    Permitting requirements and the acquisition of new rights-of-way for transmission facilities has in recent years become increasingly difficult for most utilities, including Puget Sound Power and Light Company. In order to maintain a high degree of reliability of service while being responsive to public concerns regarding the siting of high voltage (HV) transmission facilities, Puget Power has found it necessary to more heavily rely upon the use of compact lines in franchise corridors. Compaction does, however, precipitant increased levels of audible noise (AN) and radio and TV interference (RI and TVI) due to corona on the conductors and insulator assemblies. Puget Power relies upon the Bonneville Power Administration (BPA) Corona and Field Effects computer program to calculate AN and RI for new lines. Since there was some question of the program's ability to accurately represent quiet 230-kV compact designs, a joint project was undertaken with BPA to verify the program's algorithms. Long-term measurements made on an operating Puget Power 230-kV compact line confirmed the accuracy of BPA's AN model; however, the RI measurements were much lower than predicted by the BPA computer and other programs. This paper also describes how the BPA computer program can be used to calculate the voltage needed to expose insulator assemblies to the correct electric field in single test setups in HV laboratories

  7. Decision and Order in the matter of an application by Superior Wind Prince Power Inc. for an Order or Orders pursuant to section 92 of the Ontario Energy Board Act, 1998 granting leave to construct a 230 kV transmission line and associated facilities to connect a proposed 99 MW wind farm to the transmission system of Great Lakes Power Ltd. near Sault Ste Marie[In the matter of the Ontario Energy Board Act, 1998, S.O. 1998, c. 15, Schedule B

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, G.; Betts, B.; Vlahos, P.

    2005-07-28

    Superior Wind Prince Power Inc. plans to construct and operate a 99 MW wind generation facility near Sault Ste. Marie, Ontario. It has also filed an application with the Ontario Energy Board to construct transmission facilities to connect the wind farm to the transmission system of Great Lakes Power Ltd. This includes a substation with a 34.5/230 kV transformer, a high voltage breaker, and low voltage switchgear. It also includes an 11.2 km long, 230 kV transmission line and a switching station with a 230 kV breaker and related facilities. The entire project is scheduled for completion by March, 2006. The Board will proceed with the application by way of a written hearing. This document presents evidence of the applicant with reference to the request for proposals for 300 MW of Renewable Energy. The wind farm includes 66 wind turbine generators providing an output of 99 MW. Plans for a second phase would add 101 MW to the wind farm. Different high voltage and low voltage configurations have been examined on the basis of environmental and economic considerations and system reliability. The best configuration was a 34.5 kV underground collector system and a 230 kV above ground transmission line. Four alternative routes for the line were examined on the basis of environmental, technical and economic factors. This document also provided evidence of PUC Distribution Inc. and addressed issues regarding a system impact assessment, customer impact assessment, and environmental assessment. The Board questioned whether the project is needed, what impact it will have on transmission rates, and reliability of supply. It also examined if all land-use matters have been addressed. The Board approved the project subject to certain conditions regarding communications, monitoring and reporting requirements. 2 refs., 1 appendix.

  8. Proposed amendment to presidential permit PP-63 and associated modifications to 500 kV international transmission line, Forbes, Minnesota to Manitoba, Canada

    International Nuclear Information System (INIS)

    1992-10-01

    This Addendum to the Final Environmental Assessment for the Proposed Amendment to Presidential Permit PP-63 and Associated Modifications to 500 kV International Transmission Line: Forbes, Minnesota to Manitoba, Canada (DOE/EA-587) addresses Northern States Power Company's (NSP) proposed expansion of the Forbes Substation. The applicant has requested that the expansion take place on the west side of the substation, within the existing property line, instead of on the north side as originally proposed. All of the proposed construction would take place on property already owned by NSP. DOE has reviewed the environmental impacts associated with this minor modification and has determined that the conclusions reached in the environmental assessment and Finding of No Significant Impact prepared in connection with NSP's original amendment request remain valid

  9. The subfamily-specific interaction between Kv2.1 and Kv6.4 subunits is determined by interactions between the N- and C-termini.

    Directory of Open Access Journals (Sweden)

    Elke Bocksteins

    Full Text Available The "silent" voltage-gated potassium (KvS channel subunit Kv6.4 does not form electrically functional homotetramers at the plasma membrane but assembles with Kv2.1 subunits, generating functional Kv2.1/Kv6.4 heterotetramers. The N-terminal T1 domain determines the subfamily-specific assembly of Kv1-4 subunits by preventing interactions between subunits that belong to different subfamilies. For Kv6.4, yeast-two-hybrid experiments showed an interaction of the Kv6.4 N-terminus with the Kv2.1 N-terminus, but unexpectedly also with the Kv3.1 N-terminus. We confirmed this interaction by Fluorescence Resonance Energy Transfer (FRET and co-immunoprecipitation (co-IP using N-terminal Kv3.1 and Kv6.4 fragments. However, full-length Kv3.1 and Kv6.4 subunits do not form heterotetramers at the plasma membrane. Therefore, additional interactions between the Kv6.4 and Kv2.1 subunits should be important in the Kv2.1/Kv6.4 subfamily-specificity. Using FRET and co-IP approaches with N- and C-terminal fragments we observed that the Kv6.4 C-terminus physically interacts with the Kv2.1 N-terminus but not with the Kv3.1 N-terminus. The N-terminal amino acid sequence CDD which is conserved between Kv2 and KvS subunits appeared to be a key determinant since charge reversals with arginine substitutions abolished the interaction between the N-terminus of Kv2.1 and the C-terminus of both Kv2.1 and Kv6.4. In addition, the Kv6.4(CKv3.1 chimera in which the C-terminus of Kv6.4 was replaced by the corresponding domain of Kv3.1, disrupted the assembly with Kv2.1. These results indicate that the subfamily-specific Kv2.1/Kv6.4 heterotetramerization is determined by interactions between Kv2.1 and Kv6.4 that involve both the N- and C-termini in which the conserved N-terminal CDD sequence plays a key role.

  10. Aberration-corrected STEM/TEM imaging at 15 kV

    International Nuclear Information System (INIS)

    Sasaki, Takeo; Sawada, Hidetaka; Hosokawa, Fumio; Sato, Yuta; Suenaga, Kazu

    2014-01-01

    The performance of aberration-corrected (scanning) transmission electron microscopy (S/TEM) at an accelerating voltage of 15 kV was evaluated in a low-voltage microscope equipped with a cold-field emission gun and a higher-order aberration corrector. Aberrations up to the fifth order were corrected by the aberration measurement and auto-correction system using the diffractogram tableau method in TEM and Ronchigram analysis in STEM. TEM observation of nanometer-sized particles demonstrated that aberrations up to an angle of 50 mrad were compensated. A TEM image of Si[110] exhibited lattice fringes with a spacing of 0.192 nm, and the power spectrum of the image showed spots corresponding to distances of 0.111 nm. An annular dark-field STEM image of Si[110] showed lattice fringes of (111) and (22¯0) planes corresponding to lattice distances of 0.314 nm and 0.192 nm, respectively. At an accelerating voltage of 15 kV, the developed low-voltage microscope achieved atomic-resolution imaging with a small chromatic aberration and a large uniform phase. - Highlights: • Aberration-corrected STEM/TEM imaging at 15 kV demonstrated lattice fringes of Si[110] single crystal with a spacing of 0.192 nm. • To achieve this performance at a lower accelerating voltage, uniform phase area over 50 mrad is mandatory in Ronchigram and Diffractogram tableau. • This means a higher-order aberration of six-fold astigmatism should be compensated. • In addition, decreasing the effect of chromatic aberration plays an important role for improving the performance of linear scattering component at 15 kV TEM

  11. Axon initial segment Kv1 channels control axonal action potential waveform and synaptic efficacy

    NARCIS (Netherlands)

    Kole, Maarten H. P.; Letzkus, Johannes J.; Stuart, Greg J.

    2007-01-01

    Action potentials are binary signals that transmit information via their rate and temporal pattern. In this context, the axon is thought of as a transmission line, devoid of a role in neuronal computation. Here, we show a highly localized role of axonal Kv1 potassium channels in shaping the action

  12. Development of 66 kV/6.9 kV 2 MV A prototype HTS power transformer

    International Nuclear Information System (INIS)

    Bohno, T.; Tomioka, A.; Imaizumi, M.; Sanuki, Y.; Yamamoto, T.; Yasukawa, Y.; Ono, H.; Yagi, Y.; Iwadate, K.

    2005-01-01

    We have developed the technology of the producing a HTS magnet for the power transformer. Three subjects have been mainly studied, high voltage technologies, large current and low AC loss technologies and sub-cooling system technologies to establish the technology of 66 kV/6.9 kV 10 MV A class HTS power transformer. In order to verify the validity of elemental technologies, such as high voltage technologies, large current and low AC loss technologies and sub-cooling system technologies, single-phase 2 MV A class 66 kV/6.9 kV prototype HTS transformer was manufactured and tested. In the load loss (AC loss) measurement, it was obtained that the measured value of 633 W was almost corresponding to the calculated value of 576 W at the rated operation of 2 MV A. Moreover, the breakdown was not found all voltage withstand test. These test results indicate that elemental technologies were established for the development of 66 kV/6.9 kV 10 MV A class HTS power transformer

  13. Decreased expression of Kv7 channels in Hirchsprung's disease.

    Science.gov (United States)

    O'Donnell, Anne-Marie; Coyle, David; Puri, Prem

    2017-07-01

    Voltage-dependent K + channels (Kv channels) participate in electrical rhythmicity and smooth muscle responses and are regulated by excitatory and inhibitory neurotransmitters. Kv channels also participate in the interstitial cell of Cajal (ICC) and smooth muscle cell (SMC) responses to neural inputs. The Kv family consists of 12 subfamilies, Kv1-Kv12, with five members of the Kv7 family identified to date: Kv7.1-Kv7.5. A recent study identified the potassium channel Kv7.5 as having a role in the excitability of ICC-IM in the mouse colon. We therefore designed this study to test the hypothesis that Kv7 channels are present in the normal human colon and are reduced in Hirschprung's disease (HSCR). HSCR tissue specimens were collected at the time of pull-through surgery (n=10), while normal control tissue specimens were obtained at the time of colostomy closure in patients with imperforate anus (n=10). Kv7.3-Kv7.5 immunohistochemistry was performed and visualized using confocal microscopy to assess their distribution. Western blot analysis was undertaken to determine Kv7.3-Kv7.5 protein quantification. Kv7.3 and Kv7.4-immunoreactivity was co-localized with neuron and ICC markers, while Kv7.5 was found to be expressed on both ICCs and SMCs. Western blot analysis revealed similar levels of Kv7.3 and Kv7.5 expression in the normal colon and HSCR colon, while Kv7.4 proteins were found to be markedly decreased in ganglionic specimens and decreased further in aganglionic specimens. A deficiency of Kv7.4 channels in the ganglionic and aganglionic bowel may place a role in colonic dysmotility in HSCR. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Chosen Ciphertext Security with Optimal Ciphertext Overhead

    Science.gov (United States)

    Abe, Masayuki; Kiltz, Eike; Okamoto, Tatsuaki

    Every public-key encryption scheme has to incorporate a certain amount of randomness into its ciphertexts to provide semantic security against chosen ciphertext attacks (IND-CCA). The difference between the length of a ciphertext and the embedded message is called the ciphertext overhead. While a generic brute-force adversary running in 2t steps gives a theoretical lower bound of t bits on the ciphertext overhead for IND-CPA security, the best known IND-CCA secure schemes demand roughly 2t bits even in the random oracle model. Is the t-bit gap essential for achieving IND-CCA security? We close the gap by proposing an IND-CCA secure scheme whose ciphertext overhead matches the generic lower bound up to a small constant. Our scheme uses a variation of a four-round Feistel network in the random oracle model and hence belongs to the family of OAEP-based schemes. Maybe of independent interest is a new efficient method to encrypt long messages exceeding the length of the permutation while retaining the minimal overhead.

  15. Variance analysis refines overhead cost control.

    Science.gov (United States)

    Cooper, J C; Suver, J D

    1992-02-01

    Many healthcare organizations may not fully realize the benefits of standard cost accounting techniques because they fail to routinely report volume variances in their internal reports. If overhead allocation is routinely reported on internal reports, managers can determine whether billing remains current or lost charges occur. Healthcare organizations' use of standard costing techniques can lead to more realistic performance measurements and information system improvements that alert management to losses from unrecovered overhead in time for corrective action.

  16. Ingledow 500 kV substation : using mixed technology switchgear solutions for replacement

    Energy Technology Data Exchange (ETDEWEB)

    Wallner, C.; Glaubitz, P. [Siemens AG, Munich (Germany); Messinger, T. [British Columbia Transmission Corp., Vancouver, BC (Canada)

    2008-07-01

    The reliability of the 500 kV equipment at the Ingledow substation operated by BC Hydro Transmission System is of critical importance due to the energy interchange with the Bonneville Power Authority in the United States and the major role of the substation in serving the energy needs of British Columbia's densely populated Lower Mainland. Presently, the 500 kV switchyard includes 10 airblast circuit breakers and the associated current transformers which are all approaching their end of service-life. In response to environmental and safety concerns, the British Columbia Transmission Corporation adopted a policy whereby new oil-filled transformers are no longer acceptable, and the replacement of existing oil-filled transformers must be oil-free. The result is that the current transformers must be either bushing-type or sulphur-hexafluoride (SF6) type. The replacement strategies for the substation equipment consider economical, environmental and seismic issues. They have just as strong an influence on the decision process as the technical, operational and reliability aspects for the particular case or switchgear replacement in the transmission system. The Ingledow case demonstrates the advantages of using mixed technology switchgear, with its compact design flowing from gas insulated switchgear (GIS) for replacement of equipment in an outdoor switchyard. The advantages of the MTS in this case offer the possibility of future reconfiguration to improve the system reliability within the existing switchyard space. 3 refs., 5 figs.

  17. Transmission of power at high voltages

    Energy Technology Data Exchange (ETDEWEB)

    Lane, F J

    1963-01-01

    High voltage transmission is considered to be concerned with circuits and systems operating at or above 132 kV. While the general examination is concerned with ac transmission, dc systems are also included. The choice of voltage for a system will usually involve hazardous assessments of the future requirements of industry, commerce and a changing population. Experience suggests that, if the estimated economic difference between two voltages is not significant, there is good reason to choose the higher voltage, as this will make the better provision for unexpected future expansion. Two principal functions served by transmission circuits in a supply system are: (a) the transportation of energy in bulk from the generator to the reception point in the distribution system; and (b) the interconnection and integration of the generating plant and associated loads. These functions are considered and various types of system are discussed in terms of practicability, viability, quality and continuity of supply. Future developments requiring transmission voltages up to 750 kV will raise many problems which are in the main empirical. Examples are given of the type of problem envisaged and it is suggested that these can only be partially solved by theory and model operation.

  18. Harmonics in transmission power systems

    DEFF Research Database (Denmark)

    Wiechowski, Wojciech Tomasz

    . The comparison shows that results obtained used both types of the cores are the same, so it is concluded that both cores can be used for harmonic measurements. Low-inductance resistors are introduced in the secondary circuits, in series with the metering and protective relaying. On those resistors, the harmonic......Some time ago, Energinet.dk, the Transmission System Operator of the 150 kV and 400 kV transmission network in Denmark, had experienced operational malfunctions of some of the measuring and protection equipment. Also an overloading of a harmonic filter has been reported, and therefore, a need...... end only so the ground is not used as a return path. A way to reduce the capacitive coupling is to provide shielding. Harmonic currents are measured using the conventional inductive voltage transformers. Both protective and metering cores were compared if they could be used for harmonic measurements...

  19. Full Scale Test on a 100km, 150kV AC Cable

    DEFF Research Database (Denmark)

    Faria da Silva, Filipe Farria; Wiechowski, W.; Bak, Claus Leth

    2010-01-01

    phenomena is conducted. The cases analysed in this paper are: Zero-missing phenomenon, Ferranti effect, energisation transient, effect of the cable's connection in the busbar voltage and cable disconnection. For all the phenomena described in the paper measurement data are presented and it is verified......This paper presents some of the results obtained from the electrical measurements on a 99.7 km, 150 kV three-phase AC cable, connecting 215 MW offshore wind farm Horns Rev 2, located in Denmark west coast, to Denmark's 400 kV transmission network. The measurements were performed at nominal voltage...... if the obtained results are in accordance with the theory and also with simulations performed in PSCAD/EMTDC. With the exception of the cable disconnection, for all the remaining cases introduced in this paper the measurements confirmed the theoretical expectations. Depending on the cable disconnection sequence...

  20. TRUSSPOLE - Trussed Metallic Pole. Results of its application in 69 kV TL - simple circuit; Trusspole: poste metalico trelicado. Resultados da aplicacao em LT 69kV - circuito simples

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Paulo Ricardo Ralo Liberato da; Mello, Reynaldo Castriota de; Ferreira, Sirio Jose; Cadete, Marcia Augusta de Moura [MJMS - Mendes Junior Montagens e Servicos Ltda., Santa Luzia, MG (Brazil); Souza, Mauro Dias de [EGEL - Engenharia e Construcoes Ltda. (Brazil); Dantas, Roberto Pires [PLT - Projetos de Linhas de Transmissao Ltda. (Brazil)

    1995-12-31

    This report describes the origin, the development and the results of the TRUSSPOLE(Trussed Metallic Post) application in electric power transmission systems. It concerns a spatial trussed structure with a single metallic basis, similar to the concrete or wood pole, able to associate the technical and economical advantages of the trussed structures and the tubular or solid thick poles. The results obtained in the project, in load experiments of a study initial prototype and in the construction of a 69 kV Cs transmission line, with a 53.2 Km extension, using this type of structural solution, are shown 5 refs., 4 figs., 3 tabs.

  1. Study on earthquake responses of overhead traveling cranes

    International Nuclear Information System (INIS)

    Komori, A.; Fukuda, T.; Veki, T.; Kirata, M.; Hoshii, T.; Kashiwazaki, A.

    1989-01-01

    In nuclear power plants, large-size overhead traveling cranes, such as reactor building crane and turbine building crane, are installed. These overhead cranes are used for transporting heavy loads on the operation floor, and call for safety and reliability even during strong earthquake as well as under the normal operational conditions. The seismic behaviors of overhead traveling cranes, which move on the rails, may be different from those of other structures that are anchored to the building: in the case of cranes, traveling wheels and rails can slip relative to each other when the horizontal seismic force reaches the level of frictional force. In Japan, therefore, a practical guide to the seismic design that considers the sliding has been proposed. However, detailed experimental study on sliding between wheels and rails has not been carried out. In this study, the seismic behaviors of traveling overhead cranes accompanied by sliding between wheels and rails in the traveling direction are examined

  2. Canby Area Service Project substation and associated transmission line

    International Nuclear Information System (INIS)

    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

  3. Spatial Analysis of Thermal Aging of Overhead Transmission Conductors

    Czech Academy of Sciences Publication Activity Database

    Musílek, P.; Heckenbergerová, Jana; Bhuiyan, M.M.I.

    2012-01-01

    Roč. 27, č. 3 (2012), s. 1196-1204 ISSN 0885-8977 Grant - others:GA AV ČR(CZ) M100300904 Source of funding: V - iné verejné zdroje Keywords : aluminium conductor steel reinforced (ACSR) conductor * hot spot * loss of tensile strength * numerical weather prediction * power transmission lines * thermal aging Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use Impact factor: 1.519, year: 2012

  4. 250 kV aim for hvdc valves

    Energy Technology Data Exchange (ETDEWEB)

    1966-06-01

    Development now being carried out by ASEA is aimed at increasing the normal operating voltage for a mercury arc valve to 250 kV dc. The maximum direct voltage per valve group, with one valve in each arm of the bridge, is 125 kV for equipment already in operation in New Zealand, Japan, and Konti Scan. Valves for 130 kV and 133 kV operation are under construction for the Vancouver and the Pacific Intertie 1 links.

  5. Precision overhead irrigation is suitable for several Central Valley crops

    Directory of Open Access Journals (Sweden)

    Jeffrey P. Mitchell

    2016-04-01

    Full Text Available Overhead systems are the dominant irrigation technology in many parts of the world, but they are not widely used in California even though they have higher water application efficiency than furrow irrigation systems and lower labor requirements than drip systems. With water and labor perennial concerns in California, the suitability of overhead systems merits consideration. From 2008 through 2013, in studies near Five Points, California, we evaluated overhead irrigation for wheat, corn, cotton, tomato, onion and broccoli as an alternative to furrow and drip irrigation. With the exception of tomato, equal or increased yields were achieved with overhead irrigation. Many variables are involved in the choice of an irrigation system, but our results suggest that, with more research to support best management practices, overhead irrigation may be useful to a wider set of California farmers than currently use it.

  6. Hvor fosser kvælstoffet hen?

    DEFF Research Database (Denmark)

    Larsen, Torben

    Der har i Ingeniøren inden i et par måneder kunne læses adskillelige ivrige indlæg om de danske fjordes evne til at fjerne kvælstof. Kvælstof fosser ud af fjordene? lød en af de første overskrifter. Få uger efter blev det stik modsatte synspunkt fremført under overskriften Fjordene holder på kvæl...

  7. Draft environmental impact statement for construction and operation of the proposed Bangor Hydro-Electric Company`s second 345-kV transmission tie line to New Brunswick

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-10-01

    This Draft Environmental Impact Statement (DEIS) was prepared by the US Department of Energy (US DOE). The proposed action is the issuance of Presidential Permit PP-89 by DOE to Bangor Hydro-Electric Company to construct and operate a new international transmission line interconnection to New Brunswick, Canada that would consist of an 83.8 mile (US portion), 345-kilovolt (kV) alternating current transmission line from the US-Canadian border at Baileyville, Maine to an existing substation at Orrington, Maine. The principal environmental impacts of the construction and operation of the transmission line would be incremental in nature and would include the conversion of forested uplands (mostly commercial timberlands) and wetlands to right-of-way (small trees, shrubs, and herbaceous vegetation). The proposed line would also result in localized minor to moderate visual impacts and would contribute a minor incremental increase in the exposure of some individuals to electromagnetic fields. This DEIS documents the purpose and need for the proposed action, describes the proposed action and alternatives considered and provides a comparison of the proposed and alternatives routes, and provides detailed information on analyses of the environmental consequences of the proposed action and alternatives, as well as mitigative measures to minimize impacts.

  8. Effects of haloperidol on Kv4.3 potassium channels.

    Science.gov (United States)

    Lee, Hong Joon; Sung, Ki-Wug; Hahn, Sang June

    2014-10-05

    Haloperidol is commonly used in clinical practice to treat acute and chronic psychosis, but it also has been associated with adverse cardiovascular events. We investigated the effects of haloperidol on Kv4.3 currents stably expressed in CHO cells using a whole-cell patch-clamp technique. Haloperidol did not significantly inhibit the peak amplitude of Kv4.3, but accelerated the decay rate of inactivation of Kv4.3 in a concentration-dependent manner. Thus, the effects of haloperidol on Kv4.3 were estimated from the integral of the Kv4.3 currents during the depolarization pulse. The Kv4.3 was decreased by haloperidol in a concentration-dependent manner with an IC50 value of 3.6 μM. Haloperidol accelerated the decay rate of Kv4.3 inactivation and activation kinetics in a concentration-dependent manner, thereby decreasing the time-to-peak. Haloperidol shifted the voltage dependence of the steady-state activation and inactivation of Kv4.3 in a hyperpolarizing direction. Haloperidol also caused an acceleration of the closed-state inactivation of Kv4.3. Haloperidol produced a use-dependent block of Kv4.3, which was accompanied by a slowing of recovery from the inactivation of Kv4.3. These results suggest that haloperidol blocks Kv4.3 by both interacting with the open state of Kv4.3 channels during depolarization and accelerating the closed-state inactivation at subthreshold membrane potentials. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Related problems to new regional interconnections. Functioning analyses of the 500 kv Argentine system for exporting the first 1000 W to Brazil; Problemas relacionados com las nuevas interconexiones regionales. Estudios de funcionamiento del sistema argentino de 5 kV para la exportacion de los primeros 1000 MW a Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, Jose Luis; Castro, Marcelo [Servicios de Energia Elactrica y Electromecanica S.R.L., Buenos Aires (Argentina)]. E-mail: joseluisalonso@sieye.com.ar; marcelocastro@sieye.com.ar

    2001-07-01

    This work presents the analyses of static functioning (load flows) and demanded transitory stability by the Technical Procedure number 1(TP1) from CAMMESA, corresponding to the first international interconnection between Argentina and Brazil built by the CTM S.A. company. This new entailing, which started to operate in june 2000, links the Rincon de Santa Maria Transmission Station (TS) to a new TS built in Garibaldi city (Brazilian side) through a 500 kV transmission line with extension of 130 kilometers. In Garibaldi, a converter type back to back composed by two 550 kV modules was installed with 1100 MW of total nominal capacity. The Garibaldi TS is interconnected to the Ita TS, which belongs to the ELETROSUL company, through a line of 525 kV with extension of 386 kilometers. The investigations was accomplished according to the contingencies based on the agreement with CAMMESA and the dynamical model of the 50/60 Hz back to back converter (of last generation) called Capacitor Commutated Converter has been represented for all the situations.

  10. 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.

  11. Study and field verification of the effects of removing closing resistors from 500 kV circuit breakers

    International Nuclear Information System (INIS)

    Selin, D.A.; Agrawal, B.L.; Farmer, R.G.; Demcko, J.A.

    1992-01-01

    Closing resistors in EHV circuit breakers are frequently used to reduce switching transients on lines thus preventing flashovers during line energization. Maintenance and failures of such closing resistors can be costly and reduce transmission system reliability. For these reasons, APS conducted an investigation into the technical feasibility of operating its 500 kV without closing resistors. This paper describes study results of removing closing resistors from 500 kV breakers in a system which employs older technology silicon carbide type surge arresters. The paper also describes results of field tests of the expected flashover rates calculated in the study. These field tests involve repeatedly energizing a 258 mile 500 kV line using a breaker in which the closing resistors are disabled. Transient overvoltages captured during the tests are compared with predicted overvoltages. The study concludes that closing resistors may be removed from the subject system without unacceptable consequences

  12. Wireless data transmission from inside electromagnetic fields.

    Science.gov (United States)

    Huertas, José Ignacio; Barraza, Roberto; Echeverry, Julian Mauricio

    2010-01-01

    This paper describes analytical and experimental work developed to evaluate the effects of the electromagnetic fields produced by high-voltage lines (400 kV) on wireless data transmission at the 900MHz band. In this work the source of the data transmission is located inside the electromagnetic field and the reception station is located at different distances from the power lines. Different atmospheric conditions are considered.

  13. STUDY OF TRANSMISSION LINES EFFECT ON THE SYSTEM OPERATIONON OF CONTINUOUS AUTOMATIC CAB SIGNALLING

    Directory of Open Access Journals (Sweden)

    O. O. Hololobova

    2014-10-01

    Full Text Available Purpose. To conduct an effect research of the electromagnetic field of high-voltage transmission lines (HVTL (750 kV, 50 Hz on the track circuits and continuous automatic cab signalling (CACS with a signal current of 50 Hz in the areas of convergence and intersection with the transmission lines and to propose possible methods to improve noise immunity of CACS. Methodology. The measurements were performed both by means of car-laboratory and directly on rail lines. During the study the electric field strength in the range of industrial frequency directly under the transmission lines and at the distance from it to the railway lines was measured, as well as the time dependence of CACS codes with signal current frequency of 50 Hz directly under the transmission lines and at a distance from it in the absence of the train and its passing. Findings. The root causes analysis of CACS faults and failures was carried out. The effect of the electromagnetic field of high-voltage transmission lines (750 kV, 50 Hz on the track circuit and CACS with signal current of 50 Hz in the areas of convergence and intersection with the transmission line was investigated. Possible methods to improve noise immunity of CACS were considered. Originality. The effect research of transmission lines (750 kV on the operation of the automatic cab signalling on spans Prishib-Burchatsk and Privolnoye-Yelizarovo, Pridneprovsk railway in places of oblique railroads crossing and transmission lines (750 kV, 50 Hz was conducted. Electric field strength in the range of industrial frequency directly under the transmission lines and at a distance from it to the railway line, as well as the time dependences of ALSN codes with signal current frequency of 50 Hz directly under the transmission lines and at a distance from it in the absence of the train and as its passing were measured. It was found that CACS codes in track circuits under transmission lines are strongly distorted, as strength

  14. A Reference Model for Virtual Machine Launching Overhead

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hao; Ren, Shangping; Garzoglio, Gabriele; Timm, Steven; Bernabeu, Gerard; Chadwick, Keith; Noh, Seo-Young

    2016-07-01

    Cloud bursting is one of the key research topics in the cloud computing communities. A well designed cloud bursting module enables private clouds to automatically launch virtual machines (VMs) to public clouds when more resources are needed. One of the main challenges in developing a cloud bursting module is to decide when and where to launch a VM so that all resources are most effectively and efficiently utilized and the system performance is optimized. However, based on system operational data obtained from FermiCloud, a private cloud developed by the Fermi National Accelerator Laboratory for scientific workflows, the VM launching overhead is not a constant. It varies with physical resource utilization, such as CPU and I/O device utilizations, at the time when a VM is launched. Hence, to make judicious decisions as to when and where a VM should be launched, a VM launching overhead reference model is needed. In this paper, we first develop a VM launching overhead reference model based on operational data we have obtained on FermiCloud. Second, we apply the developed reference model on FermiCloud and compare calculated VM launching overhead values based on the model with measured overhead values on FermiCloud. Our empirical results on FermiCloud indicate that the developed reference model is accurate. We believe, with the guidance of the developed reference model, efficient resource allocation algorithms can be developed for cloud bursting process to minimize the operational cost and resource waste.

  15. Validities of three multislice algorithms for quantitative low-energy transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ming, W.Q.; Chen, J.H., E-mail: jhchen123@hnu.edu.cn

    2013-11-15

    Three different types of multislice algorithms, namely the conventional multislice (CMS) algorithm, the propagator-corrected multislice (PCMS) algorithm and the fully-corrected multislice (FCMS) algorithm, have been evaluated in comparison with respect to the accelerating voltages in transmission electron microscopy. Detailed numerical calculations have been performed to test their validities. The results show that the three algorithms are equivalent for accelerating voltage above 100 kV. However, below 100 kV, the CMS algorithm will introduce significant errors, not only for higher-order Laue zone (HOLZ) reflections but also for zero-order Laue zone (ZOLZ) reflections. The differences between the PCMS and FCMS algorithms are negligible and mainly appear in HOLZ reflections. Nonetheless, when the accelerating voltage is further lowered to 20 kV or below, the PCMS algorithm will also yield results deviating from the FCMS results. The present study demonstrates that the propagation of the electron wave from one slice to the next slice is actually cross-correlated with the crystal potential in a complex manner, such that when the accelerating voltage is lowered to 10 kV, the accuracy of the algorithms is dependent of the scattering power of the specimen. - Highlights: • Three multislice algorithms for low-energy transmission electron microscopy are evaluated. • The propagator-corrected algorithm is a good alternative for voltages down to 20 kV. • Below 20 kV, a fully-corrected algorithm has to be employed for quantitative simulations.

  16. Validities of three multislice algorithms for quantitative low-energy transmission electron microscopy

    International Nuclear Information System (INIS)

    Ming, W.Q.; Chen, J.H.

    2013-01-01

    Three different types of multislice algorithms, namely the conventional multislice (CMS) algorithm, the propagator-corrected multislice (PCMS) algorithm and the fully-corrected multislice (FCMS) algorithm, have been evaluated in comparison with respect to the accelerating voltages in transmission electron microscopy. Detailed numerical calculations have been performed to test their validities. The results show that the three algorithms are equivalent for accelerating voltage above 100 kV. However, below 100 kV, the CMS algorithm will introduce significant errors, not only for higher-order Laue zone (HOLZ) reflections but also for zero-order Laue zone (ZOLZ) reflections. The differences between the PCMS and FCMS algorithms are negligible and mainly appear in HOLZ reflections. Nonetheless, when the accelerating voltage is further lowered to 20 kV or below, the PCMS algorithm will also yield results deviating from the FCMS results. The present study demonstrates that the propagation of the electron wave from one slice to the next slice is actually cross-correlated with the crystal potential in a complex manner, such that when the accelerating voltage is lowered to 10 kV, the accuracy of the algorithms is dependent of the scattering power of the specimen. - Highlights: • Three multislice algorithms for low-energy transmission electron microscopy are evaluated. • The propagator-corrected algorithm is a good alternative for voltages down to 20 kV. • Below 20 kV, a fully-corrected algorithm has to be employed for quantitative simulations

  17. The influence of the 220 kv and 66 kv power electric systems and the subsystem of their servitude range in the 'chaco central' ecosystem in Paraguay; Relacion de tendido electrico de 220 kV y 66kV en el ecosistema del chaco central del Paraguay y el subsistema de su franja de servidumbre

    Energy Technology Data Exchange (ETDEWEB)

    Acosta E, Hugo Cesar [ANDE - Administracion Nacional de Electricidad, Assuncion (Paraguay)

    2001-07-01

    According to the report from DOP/EL, in a medium period of time it has been registered nine disconnections of the 66 kv power transmission line located in the Chaco zone occurred in the nocturnal period. Those disconnections affected negatively the milky processes of Colinas Menonitas, deteriorating more than 20,000 liters of milk for each cut of the electric energy service. DMA/IM has accomplished a investigation job together with DOM/FO and has found the main reasons for those disconnections, so based on them it has recommended possible solutions related to the problem.

  18. Functional properties of human neuronal Kv11 channels

    DEFF Research Database (Denmark)

    Einarsen, Karoline; Calloe, Kirstine; Grunnet, Morten

    2009-01-01

    Kv11 potassium channels are important for regulation of the membrane potential. Kv11.2 and Kv11.3 are primarily found in the nervous system, where they most likely are involved in the regulation of neuronal excitability. Two isoforms of human Kv11.2 have been published so far. Here, we present...... current characteristics of the isoforms presented in this work may contribute to the regulation of neuronal excitability....

  19. 30 CFR 56.16015 - Work or travel on overhead crane bridges.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Work or travel on overhead crane bridges. 56... Materials Storage and Handling § 56.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with substantial...

  20. 30 CFR 57.16015 - Work or travel on overhead crane bridges.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Work or travel on overhead crane bridges. 57... MINES Materials Storage and Handling § 57.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with...

  1. Alternative electrical transmission systems and their environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.

    1977-08-01

    A general description is provided of electrical transmission systems as an aid in determining their environmental impacts. Alternating current, direct current, overhead systems, underground systems, and water crossings are treated. The cost, performance, reliability, safety, and environmental impact of these systems are compared.

  2. Integration of wind power in Germany's transmission grid by using HVDC links

    Energy Technology Data Exchange (ETDEWEB)

    Wasserrab, Andreas; Fleckenstein, Marco; Balzer, Gerd [Technische Univ. Darmstadt (Germany). Inst. of Electrical Power and Energy

    2012-07-01

    This paper deals with the challenges for the integration of wind power in Germany's transmission grid. Several options for the expansion of transmission grids are discussed. The consideration focuses on HVDC technologies, which are used for further analyses. The basis of the analysis is the transmission grid of a German transmission system operator, which is implemented in a simulation tool. The model consists of the 110-kV-, 220-kV- and the 380-kV-system. In different scenarios the integration of wind power is analysed by applying HVDC links to connect the northern part of the grid with the load centres in the South. The results of load flow calculations are discussed focusing on transmission line loading and voltage stability. The paper concludes with future prospects of HVDC applications in Germany. (orig.)

  3. Accounting of allocation of production enterprises’ overhead costs

    Directory of Open Access Journals (Sweden)

    О.V. Ivaniuta

    2016-12-01

    Full Text Available Taking into account the complexity of engineering technological cycles, the use of traditional approaches to the allocation of overhead costs at the researching enterprises is inexpedient and inefficient. The authors find out that to solve this problem it is not enough to choose only one base of allocation because the formed prime cost with such an approach will not meet the reality. That is why it is suggested to use a multilevel allocation of overhead costs. The proposed approach involves the allocation of overhead costs at the following levels: fixed and variable, with shops of main and auxiliary production, calculation stations, some orders. Each level involves the selection of individual allocation bases that are grouped on economic, technological and integrated ones.

  4. Overvoltage and Insulation Coordination of Overhead Lines in Multiple-Terminal MMC-HVDC Link for Wind Power Delivery

    Directory of Open Access Journals (Sweden)

    Huiwen He

    2017-01-01

    Full Text Available The voltage-sourced converter-based HVDC link, including the modular multilevel converter (MMC configuration, is suitable for wind power, photovoltaic energy, and other kinds of new energy delivery and grid-connection. Current studies are focused on the MMC principles and controls and few studies have been done on the overvoltage of transmission line for the MMC-HVDC link. The main reason is that environmental factors have little effect on DC cables and the single-phase/pole fault rate is low. But if the cables were replaced by the overhead lines, although the construction cost of the project would be greatly reduced, the single-pole ground fault rate would be much higher. This paper analyzed the main overvoltage types in multiple-terminal MMC-HVDC network which transmit electric power by overhead lines. Based on ±500 kV multiple-terminal MMC-HVDC for wind power delivery project, the transient simulation model was built and the overvoltage types mentioned above were studied. The results showed that the most serious overvoltage was on the healthy adjacent line of the faulty line caused by the fault clearing of DC breaker. Then the insulation coordination for overhead lines was conducted according to the overvoltage level. The recommended clearance values were given.

  5. The Motion Planning of Overhead Crane Based on Suppressing Payload Residual Swing

    Directory of Open Access Journals (Sweden)

    Liu Hua-sen

    2016-01-01

    Full Text Available Since the overhead crane system is subject to under actuation system due to that overhead crane and payload are connected by flexibility wire rope. The payload generates residual swing when the overhead crane is accelerating/ decelerating the motions. This may cause trouble for the payload precise positioning and motion planning. Hence, an optimization input shaping control method is presented to reduce the under actuated overhead crane’s payload swing caused via the inertia force. The dynamic model of the overhead crane is proposed according to the physics structure of the crane. The input shaper based on the motion planning of the crane is used as the feed forward input to suppress payload residual swing. Simulation and experiment results indicate that the ZV input shaper and ZVD input shaper can reduce the payload swing of the overhead crane.

  6. Collecting and using weather data for the design of overhead lines according to IEC 60826

    International Nuclear Information System (INIS)

    Rolfseng, L.; Fikke, S.; Ghannoum, E.

    2005-01-01

    Ice and wind loads on conductors and earth wires are the most important environmental factors for the mechanical design of overhead lines. This paper addressed the economic importance of long-term recording and measuring of weather data and provided details of their use according to a recent International Electrochemical Commission technical report (60826). The procedures used to calculate design weather loads by applying the Gumbal cumulative distribution function were outlined using data collected from Studnice in the Czech Republic, where ice loads have been measured since 1940. Based on the calculations, it was suggested that predicting ice loads based on a reduced number of years may lead to either under or over designing overhead lines. An example of ice load measurements and records showed that the standard deviation of maximum annual ice loads is large. Ice and wind load data from previous technical reports were presented. It was noted that the number of years with observations, the average value and the standard deviation are the necessary parameters for making the statistical analyses of design wind and ice loads. Information on cost of overhead lines in Norway was provided, as well as details of ice load recommendations currently used. It was estimated that the total price of the uncertainty in the design ice loads for the total electric overhead line network in Norway was $30 million, representing 10 per cent of the annual replacement value of the grid. It was concluded that long-term data acquisition of ice loads could reduce investment costs when design ice loads are too high, and also alleviate damage to transmission system and loss of supply due to ice storms when the design ice value is too low. 3 refs., 4 tabs., 4 figs

  7. Superconducting power cables in Denmark - a case study

    DEFF Research Database (Denmark)

    Østergaard, Jacob

    1997-01-01

    A case study of a 450 MVA, 132 kV high temperature superconducting (HTS) power transmission cable has been carried out. In the study, a superconducting cable system is compared to a conventional cable system which is under construction for an actual transmission line in the Danish grid. The study...... that HTS cables will be less expensive for high power ratings, have lower losses for lines with a high load, and have a reduced reactive power production. The use of superconducting cables in Denmark accommodate plans by the Danish utility to make a substantial conversion of overhead lines to underground...

  8. Design and testing of reactors for 735 kV

    Energy Technology Data Exchange (ETDEWEB)

    Erb, W; Kraaij, D J

    1965-11-01

    The design and testing of five large, single phase shunt reactors rated either 110 or 55 MVAR, supplied for the 735 kV system of the Quebec Hydro Electric Commission which came into operation in the autumn of 1965 are described. As these reactors are permanently connected to the transmission lines, their losses must be considered as being continuously present and must be determined exactly. In addition to the use of a new bridge method, the losses were also measured calorimetrically for the purpose of comparison, the agreement between the two tests being remarkably good. The impulse tests with full wave and chopped wave are subsequently described.

  9. Power applications for superconducting cables in Denmark

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Østergaard, Jacob; Olsen, S. Krüger

    1999-01-01

    In Denmark a growing concern for environmental protection has lead to wishes that the open country is kept free of overhead lines as far as possible. New lines under 100 kV and existing 60/50 kV lines should be established as underground cables. Superconducting cables represent an interesting...... in cases such as transmission of energy into cities and through areas of special interest. The planned large groups of windmills in Denmark generating up to 2000 MVA or more both on dry land and off-shore will be an obvious case for the application of superconducting AC or DC cables. These opportunities...... can be combined with other new technologies such as HVDC light transmission using isolated gate bipolar transistors (IGBTs). The network needed in a system with a substantial wind power generation has to be very strong in order to handle energy fluctuations. Such a network will be possible...

  10. B. C. Hydro proposed 287 kV transmission line Kitimat to Terrace: Preliminary environmental assessment of fish and wildlife values

    Energy Technology Data Exchange (ETDEWEB)

    Hazelwood, W G

    1991-01-01

    The proposed two corridors for an additional 278 kV transmission line from Terrace to Kitimat, British Columbia were referenced for fisheries and wildlife sensitivity and impact. Route A parallels the existing powerline down the eastern edge of the Kitimat valley while Route B follows the western edge and is 12 km shorter. Fisheries values are paramount in the study area with populations of steelhead, pink, coho, chinook, chum and sockeye in both the Lakelse and Kitimat drainages. Recreational species are of strong secondary importance and support a viable tourist industry. Wildlife values are best represented by moose, bear, fur-bearers and waterfowl. Clearcut logging has depressed populations in the study area but regrowth of essential habitat and cover is allowing some species to increase in number. Trumpeter swans utilize the valley as a migration route while some remain as residents in warmer winters. The two proposed corridors were evaluated on a resource basis to determine the least impactive and sensitive route, with a general rating evolved with common criteria. The rating of Route B was significantly less sensitive than Route A, due to Route B being significantly shorter and drier. 2 figs.

  11. Some problems relating to the transmission of electrical power at very high voltage

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, A

    1965-01-01

    Some of the technical and economic factors which influence the choice of a transmission system, particularly a very high voltage one, are discussed. The stability of transmission overvoltages at mains frequency and their control by means of compensating reactances is described. Overvoltages due to circuit-breaker operation and those of atmospheric origin, and appropriate protective devices, the behaviour of equipment at 750 kV, and problems of testing are included. Finally, the 735 kV network now being installed to carry 5300 MW of hydroelectric power 650 km from the Manicouagan River to Quebec and Montreal is described.

  12. Kv7 channels can function without constitutive calmodulin tethering.

    Directory of Open Access Journals (Sweden)

    Juan Camilo Gómez-Posada

    Full Text Available M-channels are voltage-gated potassium channels composed of Kv7.2-7.5 subunits that serve as important regulators of neuronal excitability. Calmodulin binding is required for Kv7 channel function and mutations in Kv7.2 that disrupt calmodulin binding cause Benign Familial Neonatal Convulsions (BFNC, a dominantly inherited human epilepsy. On the basis that Kv7.2 mutants deficient in calmodulin binding are not functional, calmodulin has been defined as an auxiliary subunit of Kv7 channels. However, we have identified a presumably phosphomimetic mutation S511D that permits calmodulin-independent function. Thus, our data reveal that constitutive tethering of calmodulin is not required for Kv7 channel function.

  13. Technical Note: Computation of Electric Field Strength Necessary for ...

    African Journals Online (AJOL)

    Obviously, electric field is established by this charge. The effects of this field on the objects lying within its vicinity depend on its intensity. In this paper, the electric field of 33kV overhead line is considered. The aim of the paper is to determine the maximum electric field strength or potential gradient, E of the 33kV overhead ...

  14. Study on Tower Models for EHV Transmission Line

    Directory of Open Access Journals (Sweden)

    Xu Bao-Qing

    2016-01-01

    Full Text Available Lightning outage accident is one of the main factors that threat seriously the safe and reliable operation of power system. So it is very important to establish reasonable transmission tower model and evaluate the impulse response characteristic of lightning wave traveling on the transmission tower properly for determining reliable lightning protection performance. With the help of Electromagnetic Transient Program (EMTP, six 500kV tower models are built. Aiming at one line to one transformer operating mode of 500kV substation, the intruding wave overvoltage under different tower models is calculated. The effect of tower model on intruding overvoltage has been studied. The results show that different tower models can result in great differences to the calculation results. Hence, reasonable selection of the tower model in the calculation of back- strike intruding wave is very important.

  15. Fiber Bragg Grating Sensor for Fault Detection in Radial and Network Transmission Lines

    Directory of Open Access Journals (Sweden)

    Mehdi Shadaram

    2010-10-01

    Full Text Available In this paper, a fiber optic based sensor capable of fault detection in both radial and network overhead transmission power line systems is investigated. Bragg wavelength shift is used to measure the fault current and detect fault in power systems. Magnetic fields generated by currents in the overhead transmission lines cause a strain in magnetostrictive material which is then detected by Fiber Bragg Grating (FBG. The Fiber Bragg interrogator senses the reflected FBG signals, and the Bragg wavelength shift is calculated and the signals are processed. A broadband light source in the control room scans the shift in the reflected signal. Any surge in the magnetic field relates to an increased fault current at a certain location. Also, fault location can be precisely defined with an artificial neural network (ANN algorithm. This algorithm can be easily coordinated with other protective devices. It is shown that the faults in the overhead transmission line cause a detectable wavelength shift on the reflected signal of FBG and can be used to detect and classify different kind of faults. The proposed method has been extensively tested by simulation and results confirm that the proposed scheme is able to detect different kinds of fault in both radial and network system.

  16. The C-terminal HRET sequence of Kv1.3 regulates gating rather than targeting of Kv1.3 to the plasma membrane.

    Science.gov (United States)

    Voros, Orsolya; Szilagyi, Orsolya; Balajthy, András; Somodi, Sándor; Panyi, Gyorgy; Hajdu, Péter

    2018-04-12

    Kv1.3 channels are expressed in several cell types including immune cells, such as T lymphocytes. The targeting of Kv1.3 to the plasma membrane is essential for T cell clonal expansion and assumed to be guided by the C-terminus of the channel. Using two point mutants of Kv1.3 with remarkably different features compared to the wild-type Kv1.3 (A413V and H399K having fast inactivation kinetics and tetraethylammonium-insensitivity, respectively) we showed that both Kv1.3 channel variants target to the membrane when the C-terminus was truncated right after the conserved HRET sequence and produce currents identical to those with a full-length C-terminus. The truncation before the HRET sequence (NOHRET channels) resulted in reduced membrane-targeting but non-functional phenotypes. NOHRET channels did not display gating currents, and coexpression with wild-type Kv1.3 did not rescue the NOHRET-A413V phenotype, no heteromeric current was observed. Interestingly, mutants of wild-type Kv1.3 lacking HRET(E) (deletion) or substituted with five alanines for the HRET(E) motif expressed current indistinguishable from the wild-type. These results demonstrate that the C-terminal region of Kv1.3 immediately proximal to the S6 helix is required for the activation gating and conduction, whereas the presence of the distal region of the C-terminus is not exclusively required for trafficking of Kv1.3 to the plasma membrane.

  17. Development of sensorless easy-to-use overhead crane system via simulation based control

    Science.gov (United States)

    Tagawa, Yasutaka; Mori, Yoshihito; Wada, Masaomi; Kawajiri, Eisaku; Nouzuka, Kazuma

    2016-09-01

    This paper describes the newly developed overhead crane which has a sensorless vibration control system. Generally, loads which are carried by the overhead cranes are easy to vibrate and only skilled people can operate the cranes. Therefore, a lot of studies have been done to solve this problem by using feedback control with vibration sensors. However vibration sensors often break down in severe industrial environment and more reliable control systems are required. For this reason, we have been developing sensorless control system for overhead cranes. In this paper, we firstly introduce basic idea of simulation based control which is called IDCS, then overview and modeling of the overhead crane is presented. Next, the control system design of the overhead crane is discussed, and experimental results are shown for real overhead crane with 2 axes.

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

    Directory of Open Access Journals (Sweden)

    Guoming Ma

    2016-06-01

    Full Text Available 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.

  19. Effects of overhead power lines on the bird population of the Radenhaeuser Lache area in the Marburg-Biedenkopf district, Hessen; Auswirkungen von Freileitungen auf die Voegel der Radenhaeuser Lache, Landkreis Marburg-Biedenkopf/Hessen

    Energy Technology Data Exchange (ETDEWEB)

    Kliebe, K.

    1997-12-01

    In the Radenhaeuser Lache area in the county of Marburg-Biedenkopf 122 birds belonging to at least 18 species were found dead (85.2%) or injured (14.8%) in the period from 1991 to the end of July 1997. In four cases collisions with the high voltage overhead power lines (OHL) running above the flat expanse of water (42 lines of 110 kV and 380 kV) were actually seen. Collisions with the conductors seem to occur with equal frequency when birds come in to land and when they take off in flocks (particularly ducks and lapwings) whether or not this is owing to some disturbance or other (birds of prey, human beings, helicopters or hot-air balloons). (orig.) [Deutsch] Im Bereich der Radenhaeuser Lache (Kreis Marburg-Biedenkopf) wurden seit 1991 bis Ende Juli 1997 122 Voegel in mindestens 18 Arten tot (85,2%) oder verletzt (14,8%) registriert. Kollissionen mit den das Flachgewaesser ueberspannenden Hochspannungsleitungen (42 Seile mit 110 bzw. 380 kV) wurden in vier Faellen durch Sichtbeobachtungen nachgewiesen. Leitungsanfluege geschehen wohl gleichrangig beim Landeanflug und beim scharenweisen Abflug (vor allem Enten und Kiebitze) ohne oder auf Grund von Stoerungen (jagende Greifvoegel, Menschen, Hubschrauber und Heissluftballons). (orig.)

  20. Design Of Overhead Roadway At Road Intersection

    Directory of Open Access Journals (Sweden)

    Raji

    2017-08-01

    Full Text Available This project deals with the Design of overhead-roadway located at CHALLENGE junction which is a T-junction. Analysis of the existing conditions was carried out to proffers solution to the cause of the problems occurring due to the vehicle competing for space at this intersection. Before carrying out the analysis a traffic surveys at peak hours for morning 0730 to 0830 am and afternoon 0300 to 0400 pm were conducted using 15 minutes interval. From the analysis it was found out that the peak hour factor and flow rate was 0.88 and 1656pcphpl respectively corresponding to LOS E. This implies that the capacity of the existing road is no longer able to accommodate the traffic flow hence overhead roadway was introduced to improve the efficiency of the intersection. The overhead-roadway is of 140 m length with 7 spans 20 m per span. It consists of a deck slab longitudinal girders cross girders deck beam pier foundation and retailing wall. All structural parts for this Flyover were designed using Staad professional software package and Manual method.

  1. Area overhead analysis of SEF: A design methodology for tolerating SEU

    International Nuclear Information System (INIS)

    Blaquiere, Y.; Savaria, Y.

    1987-01-01

    Soft-Error filtering (SEF) is a design methodology proposed recently for implementing machines tolerant to SEU. This paper deals mainly with the evaluation and the reduction of the area overhead brought by SEF. A new shift register filtering latch configuration is proposed. The use of this latch, optimized for minimum area, reduces the area overhead by a factor of 2.6, when compared with latches optimized for time performance. A detailed analysis of the area overhead with SEF implemented on two relatively complex machines produced the following results: a SEF version of the 6800 microprocessor would require an area overhead varying between 12% and 69% depending on the SEF latch used and, a SEF version of the RISCII microprocessor would result in a 38.8% area overhead. An analysis of the cost of implementing the Hamming error correcting code on a register array is presented and this cost is compared with that of implementing SEU tolerance directly with SEF. Finally, a hybrid approach is proposed where a large register array is protected by an error correcting code whereas the isolated latches are replaced by filtering latches. This hybrid approach reduces the area overhead to 18.8% for the RISCII architecture

  2. Skeletal muscle Kv7 (KCNQ) channels in myoblast differentiation and proliferation

    International Nuclear Information System (INIS)

    Roura-Ferrer, Meritxell; Sole, Laura; Martinez-Marmol, Ramon; Villalonga, Nuria; Felipe, Antonio

    2008-01-01

    Voltage-dependent K + channels (Kv) are involved in myocyte proliferation and differentiation by triggering changes in membrane potential and regulating cell volume. Since Kv7 channels may participate in these events, the purpose of this study was to investigate whether skeletal muscle Kv7.1 and Kv7.5 were involved during proliferation and myogenesis. Here we report that, while myotube formation did not regulate Kv7 channels, Kv7.5 was up-regulated during cell cycle progression. Although, Kv7.1 mRNA also increased during the G 1 -phase, pharmacological evidence mainly involves Kv7.5 in myoblast growth. Our results indicate that the cell cycle-dependent expression of Kv7.5 is involved in skeletal muscle cell proliferation

  3. 2D-3D registration for cranial radiation therapy using a 3D kV CBCT and a single limited field-of-view 2D kV radiograph.

    Science.gov (United States)

    Munbodh, Reshma; Knisely, Jonathan Ps; Jaffray, David A; Moseley, Douglas J

    2018-05-01

    We present and evaluate a fully automated 2D-3D intensity-based registration framework using a single limited field-of-view (FOV) 2D kV radiograph and a 3D kV CBCT for 3D estimation of patient setup errors during brain radiotherapy. We evaluated two similarity measures, the Pearson correlation coefficient on image intensity values (ICC) and maximum likelihood measure with Gaussian noise (MLG), derived from the statistics of transmission images. Pose determination experiments were conducted on 2D kV radiographs in the anterior-posterior (AP) and left lateral (LL) views and 3D kV CBCTs of an anthropomorphic head phantom. In order to minimize radiation exposure and exclude nonrigid structures from the registration, limited FOV 2D kV radiographs were employed. A spatial frequency band useful for the 2D-3D registration was identified from the bone-to-no-bone spectral ratio (BNBSR) of digitally reconstructed radiographs (DRRs) computed from the 3D kV planning CT of the phantom. The images being registered were filtered accordingly prior to computation of the similarity measures. We evaluated the registration accuracy achievable with a single 2D kV radiograph and with the registration results from the AP and LL views combined. We also compared the performance of the 2D-3D registration solutions proposed to that of a commercial 3D-3D registration algorithm, which used the entire skull for the registration. The ground truth was determined from markers affixed to the phantom and visible in the CBCT images. The accuracy of the 2D-3D registration solutions, as quantified by the root mean squared value of the target registration error (TRE) calculated over a radius of 3 cm for all poses tested, was ICC AP : 0.56 mm, MLG AP : 0.74 mm, ICC LL : 0.57 mm, MLG LL : 0.54 mm, ICC (AP and LL combined): 0.19 mm, and MLG (AP and LL combined): 0.21 mm. The accuracy of the 3D-3D registration algorithm was 0.27 mm. There was no significant difference in mean TRE for the 2D-3D registration

  4. Transmission line component testing for the ITER Ion Cyclotron Heating and Current Drive System

    Science.gov (United States)

    Goulding, Richard; Bell, G. L.; Deibele, C. E.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Cambell, I. H.; Moon, R. L.; Pesavento, P. V.; Fredd, E.; Greenough, N.; Kung, C.

    2014-10-01

    High power RF testing is underway to evaluate transmission line components for the ITER Ion Cyclotron Heating and Current Drive System. The transmission line has a characteristic impedance Z0 = 50 Ω and a nominal outer diameter of 305 mm. It is specified to carry up to 6 MW at VSWR = 1.5 for 3600 s pulses, with transient voltages up to 40 kV. The transmission line is actively cooled, with turbulent gas flow (N2) used to transfer heat from the inner to outer conductor, which is water cooled. High voltage and high current testing of components has been performed using resonant lines generating steady state voltages of 35 kV and transient voltages up to 60 kV. A resonant ring, which has operated with circulating power of 6 MW for 1 hr pulses, is being used to test high power, low VSWR operation. Components tested to date include gas barriers, straight sections of various lengths, and 90 degree elbows. Designs tested include gas barriers fabricated from quartz and aluminum nitride, and transmission lines with quartz and alumina inner conductor supports. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  5. Internal services simulation control in 220/110kV power transformer station Mintia

    Science.gov (United States)

    Ciulica, D.; Rob, R.

    2018-01-01

    The main objectives in developing the electric transport and distribution networks infrastructure are satisfying the electric energy demand, ensuring the continuity of supply to customers, minimizing electricity losses in the transmission and distribution networks of public interest. This paper presents simulations in functioning of the internal services system 400/230 V ac in the 220/110 kV power transformer station Mintia. Using simulations in Visual Basic, the following premises are taken into consideration. All the ac consumers of the 220/110 kV power transformer station Mintia will be supplied by three 400/230 V transformers for internal services which can mutual reserve. In case of damaging at one transformer, the others are able to assume the entire consumption using automatic release of reserves. The simulation program studies three variants in which the continuity of supply to customers are ensured. As well, by simulations, all the functioning situations are analyzed in detail.

  6. Implementation of Particle Swarm Optimization Method for Voltage Stability Analysis in 150 kV Sub System Grati – Paiton East Java

    Science.gov (United States)

    Kusumaningtyas, A. B.; Hidayat, M. N.; Ronilaya, F.

    2018-04-01

    Based on the data from State Electric Company on 15 January 2013, the undistributed power in the 150 kV sub system Grati-Paiton Region IV, that consist of 26 bus 150 kV and 2 bus generation 500 kV system, was recorded 3.286,00 MW. At the same time, the frequency of the system was down to 49 Hz. This lead to a deficit generation and unstable voltage condition in the system. Fast Voltage Stability Index (FVSI) method is used in this research to analyze the voltage stability of the buses. For buses with unstable voltage condition, reactive power will be injected through capacitor installation. The site where the capacitor will be installed is determined using the Fast Voltage Stability Index (FVSI) method while the size of the capacitor is determined using the Particle Swarm Optimization (PSO) method. The PSO method has been applied in some researches, such as to determine optimal placement and sizing in radial distribution network as well as in transmission network.. In this research, the PSO method is used to find the Qloss of an interconnection transmission system, which in turn, the value of the Qloss is used to determine the capacitance of the capacitor needed by the system.

  7. The short-circuit test results of 6.9 kV/2.3 kV 400 kVA-class YBCO model transformer

    International Nuclear Information System (INIS)

    Tomioka, A.; Otonari, T.; Ogata, T.; Iwakuma, M.; Okamoto, H.; Hayashi, H.; Iijima, Y.; Saito, T.; Gosho, Y.; Tanabe, K.; Izumi, T.; Shiohara, Y.

    2011-01-01

    The 6.9 kV/2.3 kV 400 kVA-class single-phase YBCO model transformer with the YBCO tape with copper tape was manufactured for short-circuit current test. Short-circuit test was performed and the short-circuit current of primary winding was 346 A which was about six times larger than the rated current. The I-V characteristics of the winding did not change before and after the test. The transformer withstood short-circuit current. We are planning to turn the result into a consideration of a 66 kV/6.9 kV-20 MVA-class three-phase superconducting transformer. We are developing an elemental technology for 66 kV/6.9 kV 20 MVA-class power transformer with YBCO conductors. The protection of short-circuit technology is one of the elemental technologies for HTS transformer. Since short-circuit current is much higher than critical current of YBCO tape, there is a possibility that superconducting characteristics may be damaged during short-circuit period. We made a conductor to compose the YBCO tape with copper tape. We manufactured 6.9 kV/2.3 kV 400 kVA-class YBCO model transformer using this conductor and performed short-circuit current test. The short-circuit current of primary winding was 346 A which was about six times larger than the rated current. The I-V characteristics of the winding did not change before and after the test. We may consider this conductor withstands short-circuit current.

  8. X irradiation of human epidermis in vitro. 2. Comparison of single 44 kV and 200 kV X irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wollina, U; Fueller, J; Burger, B; Hipler, C

    1989-01-01

    On the example of the reduction of epidermal adhesion of FITC wheat germ agglutinine (WGA) the direct membrane effect of a single X irradiation (44 kV and 220 kV) was analyzed in vitro. Human normal skin and psoriasis centres were compared. Normal skin showed no alteration of microscopically visible FITC-WGA adhesion on epidermal cells over the whole dose range. Foci of psoriasis responded to doses of /ge/ 5 Gy (44 and 220 kV) with a drastic reduction of epidermal lectin binding to lower and medium cell layers. Maximum efficacy was with 5 Gy (44 kV) or 10 Gy (220 kV). A dose elevation up to 20 Gy did not result in an increase of efficacy. Topographically the radiosensitive FITC-WGA adhesion could chiefly be seen in the dermal ridges. The findings support the impression of an increased radiosensitivity of the lesional psoriatic epidermis compared with normal skin. This is connected with an abnormal differentiation of keratinocytes in psoriasis. (author).

  9. Ergonomic evaluation of a wearable assistive device for overhead work.

    Science.gov (United States)

    Rashedi, Ehsan; Kim, Sunwook; Nussbaum, Maury A; Agnew, Michael J

    2014-01-01

    Overhead work is an important risk factor for upper extremity (UE) musculoskeletal disorders. We examined the potential of a mechanical arm and an exoskeletal vest as a wearable assistive device (WADE) for overhead work. Twelve participants completed 10 minutes of simulated, intermittent overhead work, using each of three payloads (1.1, 3.4 and 8.1 kg) and with/without the WADE. Ratings of perceived discomfort (RPDs) and electromyography (EMG) were obtained for the upper arms, shoulders and low back. Using the WADE, UE RPDs decreased by ∼50% with the heavier payloads, whereas smaller (∼25%) and non-significant increases in low-back RPDs were found and were relatively independent of payload. Changes in RPDs with WADE use were consistent with physical demands indicated by EMG, though EMG-based differences in fatigue were less apparent. Participants generally preferred using the WADE, particularly with heavier payloads. These results supported the potential utility of a WADE as an intervention for overhead work.

  10. 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.

  11. 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.

  12. North Central Transmission Line: Guidelines for the environmental impact statement

    International Nuclear Information System (INIS)

    1992-01-01

    Guidelines that Manitoba Hydro must follow in the preparation of the environmental impact statement on the proposed North Central Transmission Line (TCTL) project are presented. The project consists of a 138 kV transmission line, two 25 kV distribution lines, and related ancillary structures and facilities. The review process must be sensitive to cultural and community needs and must involve those most directly affected, and should be grounded in the impacted northern communities. The review should include a project background, the proposal, a description of the existing natural and socio-economic environment, and must address employment, education and training, impacts on renewable resource harvesting, environmental impacts, social impacts and economic impacts, legal/jurisdictional issues, infrastructure, mitigation and compensation, and environmental monitoring and follow-up. 1 fig., 20 tabs

  13. Contribution of kv7.4/kv7.5 heteromers to intrinsic and calcitonin gene-related Peptide-induced cerebral reactivity

    DEFF Research Database (Denmark)

    Chadha, Preet S; Jepps, Thomas A; Carr, Georgina

    2014-01-01

    Middle cerebral artery (MCA) diameter is regulated by inherent myogenic activity and the effect of potent vasodilators such as calcitonin gene-related peptide (CGRP). Previous studies showed that MCAs express KCNQ1, 4, and 5 potassium channel genes, and the expression products (Kv7 channels) part......) participate in the myogenic control of MCA diameter. The present study investigated the contribution of Kv7.4 and Kv7.5 isoforms to myogenic and CGRP regulation of MCA diameter and determined whether they were affected in hypertensive animals....

  14. Use of TCSR with Split Windings for Shortening the Spar Cycle Time in 500 kV Lines

    Energy Technology Data Exchange (ETDEWEB)

    Matinyan, A. M., E-mail: al-drm@mail.ru; Peshkov, M. V.; Karpov, V. N.; Alekseev, N. A. [JSC “R& D Center at Federal Grid Company of Unified Power System,” (Russian Federation)

    2017-01-15

    The arc-fault recharge phenomenon in single-phase automatic reclosure (SPAR) of a line is examined. Abrief description is given of the design of a 500 kV thyristor controlled shunt reactor (TCSR) with split valve-side windings. This type of TCSR is shown to effectively quench a single-phase arc fault in a power transmission line and shortens the SPAR cycle time.

  15. The anticonvulsant retigabine suppresses neuronal Kv2-mediated currents

    DEFF Research Database (Denmark)

    Stas, Jeroen I; Bocksteins, Elke; Jensen, Camilla S

    2016-01-01

    Enhancement of neuronal M-currents, generated through KV7.2-KV7.5 channels, has gained much interest for its potential in developing treatments for hyperexcitability-related disorders such as epilepsy. Retigabine, a KV7 channel opener, has proven to be an effective anticonvulsant and has recently...

  16. An efficient transmission power control scheme for temperature variation in wireless sensor networks.

    Science.gov (United States)

    Lee, Jungwook; Chung, Kwangsue

    2011-01-01

    Wireless sensor networks collect data from several nodes dispersed at remote sites. Sensor nodes can be installed in harsh environments such as deserts, cities, and indoors, where the link quality changes considerably over time. Particularly, changes in transmission power may be caused by temperature, humidity, and other factors. In order to compensate for link quality changes, existing schemes detect the link quality changes between nodes and control transmission power through a series of feedback processes, but these approaches can cause heavy overhead with the additional control packets needed. In this paper, the change of the link quality according to temperature is examined through empirical experimentation. A new power control scheme combining both temperature-aware link quality compensation and a closed-loop feedback process to adapt to link quality changes is proposed. We prove that the proposed scheme effectively adapts the transmission power to the changing link quality with less control overhead and energy consumption.

  17. An Efficient Transmission Power Control Scheme for Temperature Variation in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jungwook Lee

    2011-03-01

    Full Text Available Wireless sensor networks collect data from several nodes dispersed at remote sites. Sensor nodes can be installed in harsh environments such as deserts, cities, and indoors, where the link quality changes considerably over time. Particularly, changes in transmission power may be caused by temperature, humidity, and other factors. In order to compensate for link quality changes, existing schemes detect the link quality changes between nodes and control transmission power through a series of feedback processes, but these approaches can cause heavy overhead with the additional control packets needed. In this paper, the change of the link quality according to temperature is examined through empirical experimentation. A new power control scheme combining both temperature-aware link quality compensation and a closed-loop feedback process to adapt to link quality changes is proposed. We prove that the proposed scheme effectively adapts the transmission power to the changing link quality with less control overhead and energy consumption.

  18. β-Secretase BACE1 Promotes Surface Expression and Function of Kv3.4 at Hippocampal Mossy Fiber Synapses.

    Science.gov (United States)

    Hartmann, Stephanie; Zheng, Fang; Kyncl, Michele C; Karch, Sandra; Voelkl, Kerstin; Zott, Benedikt; D'Avanzo, Carla; Lomoio, Selene; Tesco, Giuseppina; Kim, Doo Y; Alzheimer, Christian; Huth, Tobias

    2018-04-04

    The β-secretase β-site APP-cleaving enzyme 1 (BACE1) is deemed a major culprit in Alzheimer's disease, but accumulating evidence indicates that there is more to the enzyme than driving the amyloidogenic processing of the amyloid precursor protein. For example, BACE1 has emerged as an important regulator of neuronal activity through proteolytic and, most unexpectedly, also through nonproteolytic interactions with several ion channels. Here, we identify and characterize the voltage-gated K + channel 3.4 (Kv3.4) as a new and functionally relevant interaction partner of BACE1. Kv3.4 gives rise to A-type current with fast activating and inactivating kinetics and serves to repolarize the presynaptic action potential. We found that BACE1 and Kv3.4 are highly enriched and remarkably colocalized in hippocampal mossy fibers (MFs). In BACE1 -/- mice of either sex, Kv3.4 surface expression was significantly reduced in the hippocampus and, in synaptic fractions thereof, Kv3.4 was specifically diminished, whereas protein levels of other presynaptic K + channels such as K Ca 1.1 and K Ca 2.3 remained unchanged. The apparent loss of presynaptic Kv3.4 affected the strength of excitatory transmission at the MF-CA3 synapse in hippocampal slices of BACE1 -/- mice when probed with the Kv3 channel blocker BDS-I. The effect of BACE1 on Kv3.4 expression and function should be bidirectional, as predicted from a heterologous expression system, in which BACE1 cotransfection produced a concomitant upregulation of Kv3.4 surface level and current based on a physical interaction between the two proteins. Our data show that, by targeting Kv3.4 to presynaptic sites, BACE1 endows the terminal with a powerful means to regulate the strength of transmitter release. SIGNIFICANCE STATEMENT The β-secretase β-site APP-cleaving enzyme 1 (BACE1) is infamous for its crucial role in the pathogenesis of Alzheimer's disease, but its physiological functions in the intact nervous system are only gradually

  19. Kingsnorth-London dc transmission link

    Energy Technology Data Exchange (ETDEWEB)

    1966-03-11

    The hvdc transmission link between one of the 500 MW generators at Kingsnorth Power Station and two receiving stations in London will use a three-wire dc cable system rated to carry 1200 A at +- 266 kV. This 51-mile system will be the first dc link in the world to be used as an integral part of a complex interconnected ac network.

  20. 107.5 Gb/s 850 nm multi- and single-mode VCSEL transmission over 10 and 100 m of multi-mode fiber

    DEFF Research Database (Denmark)

    Puerta Ramírez, Rafael; Agustin, M.; Chorchos, L.

    2016-01-01

    First time successful 107.5 Gb/s MultiCAP 850 nm OM4 MMF transmissions over 10 m with multi-mode VCSEL and up to 100 m with single-mode VCSEL are demonstrated, with BER below 7% overhead FEC limit measured for each case.......First time successful 107.5 Gb/s MultiCAP 850 nm OM4 MMF transmissions over 10 m with multi-mode VCSEL and up to 100 m with single-mode VCSEL are demonstrated, with BER below 7% overhead FEC limit measured for each case....

  1. Secure and Time-Aware Communication of Wireless Sensors Monitoring Overhead Transmission Lines.

    Science.gov (United States)

    Mazur, Katarzyna; Wydra, Michal; Ksiezopolski, Bogdan

    2017-07-11

    Existing transmission power grids suffer from high maintenance costs and scalability issues along with a lack of effective and secure system monitoring. To address these problems, we propose to use Wireless Sensor Networks (WSNs) as a technology to achieve energy efficient, reliable, and low-cost remote monitoring of transmission grids. With WSNs, smart grid enables both utilities and customers to monitor, predict and manage energy usage effectively and react to possible power grid disturbances in a timely manner. However, the increased application of WSNs also introduces new security challenges, especially related to privacy, connectivity, and security management, repeatedly causing unpredicted expenditures. Monitoring the status of the power system, a large amount of sensors generates massive amount of sensitive data. In order to build an effective Wireless Sensor Network (WSN) for a smart grid, we focus on designing a methodology of efficient and secure delivery of the data measured on transmission lines. We perform a set of simulations, in which we examine different routing algorithms, security mechanisms and WSN deployments in order to select the parameters that will not affect the delivery time but fulfill their role and ensure security at the same time. Furthermore, we analyze the optimal placement of direct wireless links, aiming at minimizing time delays, balancing network performance and decreasing deployment costs.

  2. Prediction of the Voltage Quality in an Overhead Transmission Line with Distributed Parameters

    OpenAIRE

    Bulyga Leonid L.; Tarasov Evgeniy V.; Ushakov Vasily Ya.; Kharlov Nikolay N.

    2015-01-01

    The present work is devoted to investigation of an electrical transmission line with allowance for distributed parameters. From the results of voltage measurements at terminals of an actual transmission line, effective values of the voltage are calculated for every line section. Special attention is given to higher harmonics and asymmetry. Spectral composition of the voltage is presented and changes in values of harmonic components are analyzed. The effect of higher harmonics on the equipment...

  3. Life cycle assessment of the Danish electricity distribution network

    DEFF Research Database (Denmark)

    Turconi, Roberto; Simonsen, Christian G.; Byriel, Inger P.

    2014-01-01

    Purpose This article provides life cycle inventory data for electricity distribution networks and a life cycle assessment (LCA) of the Danish transmission and distribution networks. The aim of the study was to evaluate the potential importance of environmental impacts associated with distribution...... complexity and material consumption. Infrastructure provided important contributions to metal depletion and freshwater eutrophication (copper and aluminum for manufacturing of the cables and associated recycling being the most important). Underground 50-kV lines had larger impacts than overhead lines, and 0...

  4. Major Refit for CERN's 400 kV Substation

    CERN Multimedia

    2001-01-01

    The 400 kV substation on the Prévessin site brings in the electricity that powers CERN's accelerators and the majority of the Laboratory's installations. It was originally built in the 1970s for the SPS, and is one of only five privately owned 400 kV sub-stations in France. Three of the others belong to the national railway company, SNCF, supplying the Paris-Marseilles TGV line, the other is at the Cadarache research centre near mouth of the Rhone. After nearly thirty years of service, CERN's substation has just undergone a complete overhaul. The new main 18 kV switchboard for the SPS pulsed network. The electricity supply for the original Prévessin substation was from the 400 kV EDF network, delivered through three 90 MW transformers at 18 kV to the SPS pulsed network, With the arrival of LEP, two 110 MW transformers were added to supply the new accelerator. Now, as CERN gears up for the LHC, additional pulsed power capacity is needed to supply the transfer lines carrying protons from...

  5. Modeling the Virtual Machine Launching Overhead under Fermicloud

    Energy Technology Data Exchange (ETDEWEB)

    Garzoglio, Gabriele [Fermilab; Wu, Hao [Fermilab; Ren, Shangping [IIT, Chicago; Timm, Steven [Fermilab; Bernabeu, Gerard [Fermilab; Noh, Seo-Young [KISTI, Daejeon

    2014-11-12

    FermiCloud is a private cloud developed by the Fermi National Accelerator Laboratory for scientific workflows. The Cloud Bursting module of the FermiCloud enables the FermiCloud, when more computational resources are needed, to automatically launch virtual machines to available resources such as public clouds. One of the main challenges in developing the cloud bursting module is to decide when and where to launch a VM so that all resources are most effectively and efficiently utilized and the system performance is optimized. However, based on FermiCloud’s system operational data, the VM launching overhead is not a constant. It varies with physical resource (CPU, memory, I/O device) utilization at the time when a VM is launched. Hence, to make judicious decisions as to when and where a VM should be launched, a VM launch overhead reference model is needed. The paper is to develop a VM launch overhead reference model based on operational data we have obtained on FermiCloud and uses the reference model to guide the cloud bursting process.

  6. Retrofit curtain for overhead doors

    Energy Technology Data Exchange (ETDEWEB)

    Leckie, R E

    1987-12-29

    A heat insulating curtain has been developed for reducing heat losses through overhead doors of the type commonly found in industrial warehouses. The curtain consists of a reinforced polyester fabric attached to the outside top of the overhead door and moves with the door as it opens and closes. A T-shaped edge track seals the edges of the curtain to the door frame; the edge of the curtain is also T-shaped and runs up and down the track as the curtain is raised and lowered. The curtain fabric is ultraviolet resistant, durable, flexible, and transparent, and transforms the door into a solar collector which provides solar heated air to the building interior. Two curtains have been satisfactorily installed and tested at a warehouse in Calgary, Alberta. A market evaluation study was conducted to determine the possible buyers for such a door curtain. A target market consisting of those wishing to fix old, leaky doors was selected and a marketing strategy developed. The described strategy includes product development, pricing, distribution, promotion, and advertising. 2 figs., 1 tab.

  7. Inactivation as a new regulatory mechanism for neuronal Kv7 channels

    DEFF Research Database (Denmark)

    Jensen, Henrik Sindal; Grunnet, Morten; Olesen, Søren-Peter

    2007-01-01

    neuronal channels and are important for controlling excitability. Kv7.1 channels have been considered the only Kv7 channels to undergo inactivation upon depolarization. However, here we demonstrate that inactivation is also an intrinsic property of Kv7.4 and Kv7.5 channels, which inactivate to a larger...

  8. Rapid internalization of the oncogenic K+ channel K(V10.1.

    Directory of Open Access Journals (Sweden)

    Tobias Kohl

    Full Text Available K(V10.1 is a mammalian brain voltage-gated potassium channel whose ectopic expression outside of the brain has been proven relevant for tumor biology. Promotion of cancer cell proliferation by K(V10.1 depends largely on ion flow, but some oncogenic properties remain in the absence of ion permeation. Additionally, K(V10.1 surface populations are small compared to large intracellular pools. Control of protein turnover within cells is key to both cellular plasticity and homeostasis, and therefore we set out to analyze how endocytic trafficking participates in controlling K(V10.1 intracellular distribution and life cycle. To follow plasma membrane K(V10.1 selectively, we generated a modified channel of displaying an extracellular affinity tag for surface labeling by α-bungarotoxin. This modification only minimally affected K(V10.1 electrophysiological properties. Using a combination of microscopy and biochemistry techniques, we show that K(V10.1 is constitutively internalized involving at least two distinct pathways of endocytosis and mainly sorted to lysosomes. This occurs at a relatively fast rate. Simultaneously, recycling seems to contribute to maintain basal K(V10.1 surface levels. Brief K(V10.1 surface half-life and rapid lysosomal targeting is a relevant factor to be taken into account for potential drug delivery and targeting strategies directed against K(V10.1 on tumor cells.

  9. Prediction of the Voltage Quality in an Overhead Transmission Line with Distributed Parameters

    Directory of Open Access Journals (Sweden)

    Bulyga Leonid L.

    2015-01-01

    Full Text Available The present work is devoted to investigation of an electrical transmission line with allowance for distributed parameters. From the results of voltage measurements at terminals of an actual transmission line, effective values of the voltage are calculated for every line section. Special attention is given to higher harmonics and asymmetry. Spectral composition of the voltage is presented and changes in values of harmonic components are analyzed. The effect of higher harmonics on the equipment operation is analyzed.

  10. Vibrational methods of the overhead gas-pipelines technological equipment diagnostics

    International Nuclear Information System (INIS)

    Zakhezin, A.M.; Malysheva, T.V.

    2001-01-01

    The diagnostic methods of overhead gas-pipelines of the technical equipment of gas-compressor station are considered in this article by carrying out registration certification documentation. Some faults of overhead technical gas-pipelines have been proposed. This paper is devoted to the diagnostic methods of the whole gas- pipelines and their parts for some faults during expert checking fulfillment and carrying out registration certification documentation. The analysis of all defects allows to determine a 'between-repairs interval', to develop some operations to avoid these faults and to estimate the repair operation quality, to reduce failure probability. As an example of the effectiveness of technical condition service of vibrational methods by expertise fulfillment have been considered for some defects of the overhead pipelines. (author)

  11. The acrylamide (S)-1 differentially affects Kv7 (KCNQ) potassium channels

    DEFF Research Database (Denmark)

    Bentzen, Bo Hjorth; Schmitt, Nicole; Calloe, Kirstine

    2006-01-01

    The family of Kv7 (KCNQ) potassium channels consists of five members. Kv7.2 and 3 are the primary molecular correlates of the M-current, but also Kv7.4 and Kv7.5 display M-current characteristics. M-channel modulators include blockers (e.g., linopirdine) for cognition enhancement and openers (e.g...

  12. Kv10.1 potassium channel: from the brain to the tumors.

    Science.gov (United States)

    Cázares-Ordoñez, V; Pardo, L A

    2017-10-01

    The KCNH1 gene encodes the Kv10.1 (Eag1) ion channel, a member of the EAG (ether-à-go-go) family of voltage-gated potassium channels. Recent studies have demonstrated that KCHN1 mutations are implicated in Temple-Baraitser and Zimmermann-Laband syndromes and other forms of developmental deficits that all present with mental retardation and epilepsy, suggesting that Kv10.1 might be important for cognitive development in humans. Although the Kv10.1 channel is mainly expressed in the mammalian brain, its ectopic expression occurs in 70% of human cancers. Cancer cells and tumors expressing Kv10.1 acquire selective advantages that favor cancer progression through molecular mechanisms that involve several cellular pathways, indicating that protein-protein interactions may be important for Kv10.1 influence in cell proliferation and tumorigenesis. Several studies on transcriptional and post-transcriptional regulation of Kv10.1 expression have shown interesting mechanistic insights about Kv10.1 role in oncogenesis, increasing the importance of identifying the cellular factors that regulate Kv10.1 expression in tumors.

  13. 800 kW transmission line research at Leatherhead

    Energy Technology Data Exchange (ETDEWEB)

    1964-05-29

    The experimental transmission line was installed at Leatherhead to enable the Central Electricity Research Laboratories to study the insulators, fittings, and conductors likely to be needed for ac power transmission at voltages up to the equivalent of 800 kV three-phase. Continuous recording will be made of corona power loss and radio and television interference. For this purpose C.E.R.L. has developed a statistical radio-interference recorder. The instrumentation also includes an automatic corona-loss bridge and data logger.

  14. In vitro measurement of CT density and estimation of stenosis related to coronary soft plaque at 100 kV and 120 kV on ECG-triggered scan

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, Jun, E-mail: horiguch@hiroshima-u.ac.jp [Department of Clinical Radiology, Hiroshima University Hospital, 1-2-3, Kasumi-cho, Minami-ku, Hiroshima 734-8551 (Japan); Fujioka, Chikako, E-mail: fujioka@hiroshima-u.ac.jp [Department of Clinical Radiology, Hiroshima University Hospital, 1-2-3, Kasumi-cho, Minami-ku, Hiroshima 734-8551 (Japan); Kiguchi, Masao, E-mail: kiguchi@hiroshima-u.ac.jp [Department of Clinical Radiology, Hiroshima University Hospital, 1-2-3, Kasumi-cho, Minami-ku, Hiroshima 734-8551 (Japan); Yamamoto, Hideya, E-mail: hideyayama@hiroshima-u.ac.jp [Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical Sciences and Hiroshima University Hospital, 1-2-3, Kasumi-cho, Minami-ku, Hiroshima 734-8551 (Japan); Shen, Yun, E-mail: Yuna.Shen@ge.com [CT Lab of Great China, GE Healthcare, L12 and L15, Office Tower, Langham Place, 8 Argyle Street, Mongkok Kowloon (Hong Kong); Kihara, Yasuki, E-mail: ykihara@hiroshima-u.ac.jp [Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical Sciences and Hiroshima University Hospital, 1-2-3, Kasumi-cho, Minami-ku, Hiroshima 734-8551 (Japan)

    2011-02-15

    Purpose: The purpose of the study was to compare 100 kV and 120 kV prospective electrocardiograph (ECG)-triggered axial coronary 64-detector CT angiography (64-MDCTA) in soft plaque diagnosis. Materials and methods: Coronary artery models (n = 5) with artificial soft plaques (-32 HU to 53 HU at 120 kV) with three stenosis levels (25%, 50% and 75%) on a cardiac phantom (mimicking slim patient's environment) were scanned in heart rates of 55, 60 and 65 beats per minute (bpm). Four kinds of intracoronary enhancement (205 HU, 241 HU, 280 HU and 314 HU) were simulated. The soft plaque density and the measurement error of stenosis (in percentage), evaluated by two independent observers, were compared between 100 kV and 120 kV. The radiation dose was estimated. Results: Interobserver correlation of the measurement was excellent (density; r = 0.95 and stenosis measure; r = 0.97). Neither the density of soft plaque nor the measurement error of stenosis was different between 100 kV and 120 kV (p = 0.22 and 0.08). The estimated radiation doses were 2.0 mSv and 3.3 mSv (in 14 cm coverage) on 100 kV and 120 kV prospective ECG-triggered axial scans, respectively. Conclusion: The 100 kV prospective ECG-triggered coronary MDCTA has comparable performance to 120 kV coronary CTA in terms of soft plaque densitometry and measurement of stenosis, with a reduced effective dose of 2 mSv.

  15. Rearrangement of potassium ions and Kv1.1/Kv1.2 potassium channels in regenerating axons following end-to-end neurorrhaphy: ionic images from TOF-SIMS.

    Science.gov (United States)

    Liu, Chiung-Hui; Chang, Hung-Ming; Wu, Tsung-Huan; Chen, Li-You; Yang, Yin-Shuo; Tseng, To-Jung; Liao, Wen-Chieh

    2017-10-01

    The voltage-gated potassium channels Kv1.1 and Kv1.2 that cluster at juxtaparanodal (JXP) regions are essential in the regulation of nerve excitability and play a critical role in axonal conduction. When demyelination occurs, Kv1.1/Kv1.2 activity increases, suppressing the membrane potential nearly to the equilibrium potential of K + , which results in an axonal conduction blockade. The recovery of K + -dependent communication signals and proper clustering of Kv1.1/Kv1.2 channels at JXP regions may directly reflect nerve regeneration following peripheral nerve injury. However, little is known about potassium channel expression and its relationship with the dynamic potassium ion distribution at the node of Ranvier during the regenerative process of peripheral nerve injury (PNI). In the present study, end-to-end neurorrhaphy (EEN) was performed using an in vivo model of PNI. The distribution of K + at regenerating axons following EEN was detected by time-of-flight secondary-ion mass spectrometry. The specific localization and expression of Kv1.1/Kv1.2 channels were examined by confocal microscopy and western blotting. Our data showed that the re-establishment of K + distribution and intensity was correlated with the functional recovery of compound muscle action potential morphology in EEN rats. Furthermore, the re-clustering of Kv1.1/1.2 channels 1 and 3 months after EEN at the nodal region of the regenerating nerve corresponded to changes in the K + distribution. This study provided direct evidence of K + distribution in regenerating axons for the first time. We proposed that the Kv1.1/Kv1.2 channels re-clustered at the JXP regions of regenerating axons are essential for modulating the proper patterns of K + distribution in axons for maintaining membrane potential stability after EEN.

  16. Bladder contractility is modulated by Kv7 channels in pig detrusor

    DEFF Research Database (Denmark)

    Svalø, Julie; Bille, Michala; Parameswaran Theepakaran, Neeraja

    2013-01-01

    Kv7 channels are involved in smooth muscle relaxation, and accordingly we believe that they constitute potential targets for the treatment of overactive bladder syndrome. We have therefore used myography to examine the function of Kv7 channels in detrusor, i.e. pig bladder, with a view...... relaxation, suggesting that Kv7.2 and/or Kv7.4 channels constitute the subtypes that are relevant to bladder contractility. The effects of retigabine and ML213 were attenuated by pre-incubation with 10µM XE991 (Kv7.1-7.5 channel blocker) (P...

  17. Assessment of Lightning Shielding Performance of a 400 kV Double-Circuit Fully Composite Pylon

    DEFF Research Database (Denmark)

    Jahangirl, Tohid; Bak, Claus Leth; Silva, Filipe Miguel Faria da

    2016-01-01

    of diagonal and differs from other widely used configurations in overhead transmission lines i.e. horizontal, delta and vertical configurations. On the other hand, unlike traditional steel lattice towers, the pylon removes access to ground potential due to its non-conductive materials and therefore......, the lightning shielding of pylon requires a ground potential access to shield wires which can be achieved by utilizing ground cable inside the hollow cross-arm and pylon body. However, efficient assigning of lightning shielding system for the fully composite pylon is one of the major challenges...

  18. The US market for high-temperature superconducting wire in transmission cable applications

    Energy Technology Data Exchange (ETDEWEB)

    Forbes, D

    1996-04-01

    Telephone interviews were conducted with 23 utility engineers concerning the future prospects for high-temperature superconducting (HTS) transmission cables. All have direct responsibility for transmission in their utility, most of them in a management capacity. The engineers represented their utilities as members of the Electric Power Research Institute`s Underground Transmission Task Force (which has since been disbanded). In that capacity, they followed the superconducting transmission cable program and are aware of the cryogenic implications. Nineteen of the 23 engineers stated the market for underground transmission would grow during the next decade. Twelve of those specified an annual growth rate; the average of these responses was 5.6%. Adjusting that figure downward to incorporate the remaining responses, this study assumes an average growth rate of 3.4%. Factors driving the growth rate include the difficulty in securing rights-of-way for overhead lines, new construction techniques that reduce the costs of underground transmission, deregulation, and the possibility that public utility commissions will allow utilities to include overhead costs in their rate base. Utilities have few plans to replace existing cable as preventive maintenance, even though much of the existing cable has exceeded its 40-year lifetime. Ten of the respondents said the availability of a superconducting cable with the same life-cycle costs as a conventional cable and twice the ampacity would induce them to consider retrofits. The respondents said a cable with those characteristics would capture 73% of their cable retrofits.

  19. Power Transmission from Large Offshore Wind Farms

    DEFF Research Database (Denmark)

    Pedersen, Jørgen Kaas

    1999-01-01

    The major part of the coming wind farms in Denmark will be placed offshore. If the location is near a grid with a high short circuit level the power can be transmitted as AC.If the wind farm is far away from the grid and the grid perhaps has a low short circuit level, the best solution...... for transmitting the power can be by DC. At the moment it is possible to build self-commutating DC/AC-inverters up to about 150 kV. This paper will show a concept to a solution for a wind farm and a transmission system based on synchronous generators or a powerformer® with a rated voltage of 50 kV. The AC power...... will be rectified and boosted to a fixed DC voltage (e.g. 100 kV). The speed of the generator will be variable, depending of the wind but also controlled with the duty-cycle of the booster. In that way all wind turbines can be connected to the same DC bus and the cable to the inverter station connected to the AC...

  20. Effect of particle size, filler loadings and x-ray tube voltage on the transmitted x-ray transmission in tungsten oxide—epoxy composites

    International Nuclear Information System (INIS)

    Noor Azman, N.Z.; Siddiqui, S.A.; Hart, R.; Low, I.M.

    2013-01-01

    The effect of particle size, filler loadings and x-ray tube voltage on the x-ray transmission in WO 3 -epoxy composites has been investigated using the mammography unit and a general radiography unit. Results indicate that nano-sized WO 3 has a better ability to attenuate the x-ray beam generated by lower tube voltages (25–35 kV) when compared to micro-sized WO 3 of the same filler loading. However, the effect of particle size on x-ray transmission was negligible at the higher x-ray tube voltages (40–120 kV). - Highlights: ► Investigated the effect of particle size of WO 3 on the x-ray attenuation ability. ► Nano-sized WO 3 has a better ability to attenuate lower x-ray energies (22–49 kV p ). ► Particle size has negligible effect at the higher x-ray energy range (40–120 kV p ).

  1. Alternative approaches to transmission investment

    Energy Technology Data Exchange (ETDEWEB)

    Thon, S. [AltaLink Management Ltd., Calgary, AB (Canada)

    2004-07-01

    AltaLink is Canada's first stand-alone power transmission company, serving all major centres in Alberta and 85 per cent of Alberta's population. It has more than $1 billion in assets, 11,500 km of transmission lines and 300 substations. It was noted that there has not been any significant investment in power transmission in Alberta for the past 20 years, partly because transmission assets have a very long lifespan. The new role of the power grid is to ensure reliability, safety, efficiency, market effectiveness and supply diversity. The benefits and costs of AltaLink's 500 kV North-South upgrade project were outlined. It was noted that a healthy transmission system is the basis for economic growth throughout the province and for the development of Alberta's resource base. The transmission policy in Alberta endorses that all consumers pay postage stamp tariffs. It also promotes a proactive plan for transmission projects, the time to maximum rate (TMR) in limited cases only, a congestion-free grid under normal conditions, the financial commitment of generators, specific time limits on permitting processes, and regional interconnections to benefit all customers. tabs., figs.

  2. Nitrate leaching beneath a containerized nursery crop receiving trickle or overhead irrigation.

    Science.gov (United States)

    Colangelo, D J; Brand, M H

    2001-01-01

    Container production of nursery crops is intensive and a potential source of nitrogen release to the environment. This study was conducted to determine if trickle irrigation could be used by container nursery producers as an alternative to standard overhead irrigation to reduce nitrogen release into the environment. The effect of overhead irrigation and trickle irrigation on leachate nitrate N concentration, flow-weighted nitrate N concentration, leachate volume, and plant growth was investigated using containerized rhododendron (Rhododendron catawbiense Michx. 'Album') supplied with a controlled-release fertilizer and grown outdoors on top of soil-monolith lysimeters. Leachate was collected over two growing seasons and overwinter periods, and natural precipitation was allowed as a component of the system. Precipitation accounted for 69% of the water entering the overhead-irrigated system and 80% of the water entering the trickle-irrigated system. Leachate from fertilized plants exceeded the USEPA limit of 10 mg L(-1) at several times and reached a maximum of 26 mg L(-1) with trickle irrigation. Average annual loss of nitrate N in leachate for fertilized treatments was 51.8 and 60.5 kg ha(-1) for the overhead and trickle treatments, respectively. Average annual flow-weighted concentration of nitrate N in leachate of fertilized plants was 7.2 mg L(-1) for overhead irrigation and 12.7 mg L(-1) for trickle irrigation. Trickle irrigation did not reduce the amount of nitrate N leached from nursery containers when compared with overhead irrigation because precipitation nullified the potential benefits of reduced leaching fractions and irrigation inputs provided under trickle irrigation.

  3. Chronic electroconvulsive stimulation but not chronic restraint stress modulates mRNA expression of voltage-dependent potassium channels Kv7.2 and Kv11.1 in the rat piriform cortex

    DEFF Research Database (Denmark)

    Hjæresen, Marie-Louise; Hageman, Ida; Wörtwein, Gitta

    2008-01-01

    The mechanisms by which stress and electroconvulsive therapy exert opposite effects on the course of major depression are not known. Potential candidates might include the voltage-dependent potassium channels. Potassium channels play an important role in maintaining the resting membrane potential...... and controlling neuronal excitability. To explore this hypothesis, we examined the effects of one or several electroconvulsive stimulations and chronic restraint stress (6 h/day for 21 days) on the expression of voltage-dependent potassium channel Kv7.2, Kv11.1, and Kv11.3 mRNA in the rat brain using in situ...... hybridization. Repeated, but not acute, electroconvulsive stimulation increased Kv7.2 and Kv11.1 mRNA levels in the piriform cortex. In contrast, restraint stress had no significant effect on mRNA expression of Kv7.2, Kv11.1, or Kv11.3 in any of the brain regions examined. Thus, it appears that the investigated...

  4. Grounding modelling for transient overvoltage simulation in electric power transmission

    International Nuclear Information System (INIS)

    Moreno O, German; Valencia V, Jaime A; Villada, Fernando

    1992-01-01

    Grounding plays an important role in transmission line outages and consequently on electric energy transmission quality indexes. Fundamentals of an accurate modelling for transient behaviour analysis, particularly for the response of transmission lines to lightning, are presented. Also, a method to take into account the electromagnetic propagation guided by the grounding electrodes and finally to assess the grounding impedance in order to simulate the transmission line behaviour under lightning is presented. Analysis of impedance behaviour for diverse configurations and simulation results of over voltages on a real 220 kV line are presented to illustrate the capabilities of the method and of the computational program developed

  5. Seismic behavior with sliding of overhead travelling crane

    International Nuclear Information System (INIS)

    Komori, Akio; Ueki, Takashi; Hirata, Masami; Hoshii, Tsutomu; Kashiwazaki, Akihiro.

    1989-01-01

    In this study, the seismic behavior of an overhead travelling crane with the sliding between travelling wheels and rails is examined. First, the dynamic characteristic test of the actual crane installed in a reactor building and the sliding test of the rigid-element model to observe the basic sliding characteristic were performed. Next, to examine the dynamic response with sliding, shaking tests using the scaled model of an actual crane were conducted. From these results, useful design information about seismic behavior of an overhead travelling crane was obtained. It was also observed that numerical predictions considering sliding behavior have good agreement with the experimental results and are applicable to seismic design. (author)

  6. Atlas transmission line breakdown analysis

    CERN Document Server

    Nielsen, K E; Ballard, E O; Elizondo, J M; Gribble, R F; McCuistian, B T; Parsons, W M

    1999-01-01

    The Atlas facility will use 24 radially converging, vertically oriented and tapered, oil insulated, triplate transmission lines between the Marx generators and the central load region. Among the requirements of the transmission lines are low inductance and high reliability. The inter-conductor gap is nominally 2 cm and the lines taper from a height of 1.75 m at the Marx end to 0.32 m at the output end. The aluminum conductors, held together by 20 insulating spacers, are assembled and inserted as a unit into radial oil-filled steel tanks. The negative, high-voltage, center conductor is 2.54-cm thick and the outer ground conductors are 1.59-cm thick. All 24 triplate transmission lines connect to a transition section at near 1 m radius that couples the transmission lines to a disk/conical solid- dielectric-insulated power flow channel transmission line terminating at the load. Peak operating voltage on the lines can be as high as 240 kV with an effective stress time of 0.8 mu s. Testing of small sections of the ...

  7. Touch and step potential analysis at 23.9kV to 4.16kV & 13.8kV to 4.16kV distribution substations with pad-mounted transformers, floating grounds, and other exposed ungrounded metal bodies using WinIGS

    Science.gov (United States)

    Guzman, David G.

    An electrical substation is composed of various subsystems that allow for the effective and safe operation of the power grid. One of the subsystems integrating a conventional substation is defined as the ground grid system. This system allows for the effective operation of the power grid and all the electrical equipment connected to it by providing a ground potential reference, commonly known as the system ground. In addition, the ground grid system provides safety to the workers and the public transiting inside or living nearby a substation by reducing the step and touch potential (or voltage) levels present during a system fault. In today's utility industry practices there is an increasing trend for using pad-mounted electrical equipment for substation applications in an effort to construct new or upgrade existing electrical facilities inside limited property spaces. This thesis work presents an analysis for the effects of touch and step voltages at existing distribution substations where 23.9kV to 4.16kV & 13.8kV to 4.16kV pad-mounted transformers and other pad-mounted switchgear was installed to replace the traditional station class equipment. Moreover, this study will expose modeling techniques employed to define and determine the effects of floating grounds and other exposed metal bodies inside or surrounding these substations using WinIGS; this is in an effort to determine any risks of electric shock associated with this type of installations. The results presented in this work are intended to verify the requirements for the ground grid analysis and design for 4.16kV distribution substations with pad-mounted equipment in order to prevent dangerous step and touch voltage levels appearing at these sites during system faults; and ultimately prevent exposing individuals to the risk of an electric shock.

  8. Reduced sensory synaptic excitation impairs motor neuron function via Kv2.1 in spinal muscular atrophy.

    Science.gov (United States)

    Fletcher, Emily V; Simon, Christian M; Pagiazitis, John G; Chalif, Joshua I; Vukojicic, Aleksandra; Drobac, Estelle; Wang, Xiaojian; Mentis, George Z

    2017-07-01

    Behavioral deficits in neurodegenerative diseases are often attributed to the selective dysfunction of vulnerable neurons via cell-autonomous mechanisms. Although vulnerable neurons are embedded in neuronal circuits, the contributions of their synaptic partners to disease process are largely unknown. Here we show that, in a mouse model of spinal muscular atrophy (SMA), a reduction in proprioceptive synaptic drive leads to motor neuron dysfunction and motor behavior impairments. In SMA mice or after the blockade of proprioceptive synaptic transmission, we observed a decrease in the motor neuron firing that could be explained by the reduction in the expression of the potassium channel Kv2.1 at the surface of motor neurons. Chronically increasing neuronal activity pharmacologically in vivo led to a normalization of Kv2.1 expression and an improvement in motor function. Our results demonstrate a key role of excitatory synaptic drive in shaping the function of motor neurons during development and the contribution of its disruption to a neurodegenerative disease.

  9. A Low-Overhead Cooperative Retransmission Scheme for IR-UWB Networks

    Directory of Open Access Journals (Sweden)

    Ghasem Naddafzadeh Shirazi

    2008-01-01

    Full Text Available The UWB unique properties such as fine ranging and immunity to small scale fading are utilized in order to exploit the multiuser diversity in UWB networks. The optimal cooperation strategies in the absence of control packet overhead are analyzed in the proactive and reactive settings. It is shown that the proposed method achieves a considerable diversity gain while minimizing the overhead of control packet exchange that is required for coordination among the relays.

  10. Superconducting power transmission: the perils and promise

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, E B

    1976-06-01

    The development of bulk electricity transmission systems must be considered in the light of changing growth rates, increasing resistances to ehv overhead transmission and the tendency to concentrate generation in fewer sites. Helium-cooled or superconducting cables possess technical characteristics which will make them suitable as utility network components for power transmission over distances of ten to several hundred miles. These properties are illustrated by considering two applications in existing electrical networks. The first is a 43 mile system to transmit 4800 MVA and the second is a potential application under study in Pennsylvania to transmit 10,000 MVA over a distance of 350 miles or so. Helium-cooled versions of these transmission systems were designed to permit technical and economic evaluations. The major groups and institutions throughout the world engaged in the development of helium-cooled cables are listed and aspects of the technical approaches are briefly described.

  11. The transient outward current in mice lacking the potassium channel gene Kv1.4

    Science.gov (United States)

    London, Barry; Wang, Dao W; Hill, Joseph A; Bennett, Paul B

    1998-01-01

    The transient outward current (Ito) plays a prominent role in the repolarization phase of the cardiac action potential. Several K+ channel genes, including Kv1.4, are expressed in the heart, produce rapidly inactivating currents when heterologously expressed, and may be the molecular basis of Ito.We engineered mice homozygous for a targeted disruption of the K+ channel gene Kv1.4 and compared Ito in wild-type (Kv1.4+/+), heterozygous (Kv1.4+/-) and homozygous ‘knockout’ (Kv1.4−/−) mice. Kv1.4 RNA was truncated in Kv1.4−/− mice and protein expression was absent.Adult myocytes isolated from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice had large rapidly inactivating outward currents. The peak current densities at 60 mV (normalized by cellular capacitance, in pA pF−1; means ± s.e.m.) were 53.8 ± 5.3, 45.3 ± 2.2 and 44.4 ± 2.8 in cells from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice, respectively (P mice.The voltage dependence and time course of inactivation were not changed by targeted disruption of Kv1.4. The mean best-fitting V½ (membrane potential at 50 % inactivation) values for myocytes from Kv1.4 +/+, Kv1.4+/− and Kv1.4−/− mice were -53.5 ± 3.7, -51.1 ± 2.6 and -54.2 ± 2.4 mV, respectively. The slope factors (k) were -10.1 ± 1.4, -8.8 ± 1.4 and -9.5 ± 1.2 mV, respectively. The fast time constants for development of inactivation at -30 mV were 27.8 ± 2.2, 26.2 ± 5.1 and 19.6 ± 2.1 ms in Kv1.4+/+, Kv1.4+/− and Kv1.4−/− myocytes, respectively. At +30 mV, they were 35.5 ± 2.6, 30.0 ± 2.1 and 28.7 ± 1.6 ms, respectively. The time constants for the rapid phase of recovery from inactivation at -80 mV were 32.5 ± 8.2, 23.3 ± 1.8 and 39.0 ± 3.7 ms, respectively.Nearly the entire inactivating component as well as more than 60 % of the steady-state outward current was eliminated by 1 mm 4-aminopyridine in Kv1.4+/+, Kv1.4+/− and Kv1.4−/− myocytes.Western blot analysis of heart membrane extracts showed no significant

  12. Differential expression of the Kv1 voltage-gated potassium channel family in the rat nephron.

    Science.gov (United States)

    Carrisoza-Gaytán, Rolando; Salvador, Carolina; Diaz-Bello, Beatriz; Escobar, Laura I

    2014-10-01

    Several potassium (K(+)) channels contribute to maintaining the resting membrane potential of renal epithelial cells. Apart from buffering the cell membrane potential and cell volume, K(+) channels allow sodium reabsorption in the proximal tubule (PT), K(+) recycling and K(+) reabsorption in the thick ascending limb (TAL) and K(+) secretion and K(+) reabsorption in the distal convoluted tubule (DCT), connecting tubule (CNT) and collecting duct. Previously, we identified Kv.1.1, Kv1.3 and Kv1.6 channels in collecting ducts of the rat inner medulla. We also detected intracellular Kv1.3 channel in the acid secretory intercalated cells, which is trafficked to the apical membrane in response to dietary K(+) to function as a secretory K(+) channel. In this work we sought to characterize the expression of all members of the Kv1 family in the rat nephron. mRNA and protein expression were detected for all Kv1 channels. Immunoblots identified differential expression of each Kv1 in the cortex, outer and inner medulla. Immunofluorescence labeling detected Kv1.5 in Bowman´s capsule and endothelial cells and Kv1.7 in podocytes, endothelial cells and macula densa in glomeruli; Kv1.4, Kv1.5 and Kv1.7 in PT; Kv1.2, Kv1.4 and Kv1.6 in TAL; Kv1.1, Kv1.4 and Kv1.6 in DCT and CNT and Kv1.3 in DCT, and all the Kv1 family in the cortical and medullary collecting ducts. Recently, some hereditary renal syndromes have been attributed to mutations in K(+) channels. Our results expand the repertoire of K(+) channels that contribute to K(+) homeostasis to include the Kv1 family.

  13. Annular dark field electron microscope images with better than 2 A resolution at 100 kV

    International Nuclear Information System (INIS)

    Shin, D.H.; Kirkland, E.J.; Silcox, J.

    1989-01-01

    High-resolution scanning transmission electron microscope (STEM) images in the annular dark field (ADF) imaging mode approaching the theoretical point-to-point resolution limit are presented. The ADF images were obtained from a high T c superconducting YBa 2 Cu 3 O 7-x thin-film specimen at 100 kV. The 1.9 A resolution lattice image, which is the smallest lattice spacing in the specimen, corresponds to the minimum resolvable spatial frequency with 5% contrast in the contrast transfer function for annular dark field, and is smaller than the resolution limit given by the Rayleigh criterion. This demonstrates that STEM ADF imaging can have a resolution approximately 40% better than that of the bright field conventional transmission electron microscope (CTEM) imaging at Scherzer condition

  14. BPA/Puget Power Northwest Washington Transmission Project. Supplemental Draft Environmental Impact Statement

    International Nuclear Information System (INIS)

    1995-04-01

    Bonneville Power Administration and Puget Sound Power ampersand Light Company propose to upgrade the existing high-voltage transmission system in the Whatcom and Skagit County area between the towns of Custer and Sedro Woolley, including within the City of Bellingham, starting in 1995. The upgrades of the interconnected 230-kV and 115-kV systems are needed to increase the import capacity on a nearby U.S.-Canada 500-kV intertie by about 850 megawatts (MW). BPA and Puget Power would share the increase in north-south transfer capability. An existing BPA 230-kV single-circuit, wood-pole H-frame transmission line would be upgraded to a 230-kV lattice-steel double-circuit line. A Draft Environmental Impact Statement (DEIS) for the project was issued in November 1993. New 1994 studies showed that other improvements to Puget Power's system, and the addition of local generation has lessened local reliability problems. Also in 1994, BPA reevaluated all existing projects with this goal in mind. BPA and Puget determined that benefits would still result from this project, and that additional transfer capacity and improved system integrity warrant the expenditures. Given the changes in need, BPA decided to issue a Supplemental DEIS, and provide a second public review-and-comment period. The proposed action is designated Option 1. Impacts would be low to moderate and localized. Effects on soils and water resources in sensitive areas would be low to moderate; there would be little increase in magnetic fields, noise levels would approximate existing levels; and land use and property value impacts would be low. Threatened and endangered species would not be adversely affected, and all proposed Sections in wetlands would be covered by Nationwide Permit. Visual and socioeconomic impacts would be low to moderate. No cultural resources listed on the National Register of Historic Places would be affected

  15. VT VEC Primary Overhead and Underground Distribution Lines

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) Vermont Electric Cooperative, Inc. (VEC) Primary Overhead and Underground Distribution Lines. VEC’s Distribution lines were drawn from pole to...

  16. 78 FR 50405 - Amended Application for Presidential Permit; Northern Pass Transmission LLC

    Science.gov (United States)

    2013-08-19

    ... Pass proposes to construct and operate a primarily overhead high-voltage direct current (HVDC) electric transmission line that would originate at an HVDC converter station to be constructed at the Des Cantons Substation in Qu[eacute]bec, Canada, then would be converted from HVDC to alternating current (AC) in...

  17. Limiting electric fields of HVDC overhead power lines.

    Science.gov (United States)

    Leitgeb, N

    2014-05-01

    As a consequence of the increased use of renewable energy and the now long distances between energy generation and consumption, in Europe, electric power transfer by high-voltage (HV) direct current (DC) overhead power lines gains increasing importance. Thousands of kilometers of them are going to be built within the next years. However, existing guidelines and regulations do not yet contain recommendations to limit static electric fields, which are one of the most important criteria for HVDC overhead power lines in terms of tower design, span width and ground clearance. Based on theoretical and experimental data, in this article, static electric fields associated with adverse health effects are analysed and various criteria are derived for limiting static electric field strengths.

  18. Overvoltages transferred from a network of 220 kV to 15.65 kV level of the step-up transformer in HPP 'Bajina Bašta'

    Directory of Open Access Journals (Sweden)

    Vukelja Petar

    2011-01-01

    Full Text Available The paper presents the results of research in lightning surge waves and switching overvoltages transferred from a network of 220 kV to the 15.65 kV level of the step-up transformer in HPP 'Bajina Bašta'. Analysis of survey results lead to conclusion that transferred overvoltages can endanger 15.65 kV transformer windings and stator winding insulation. It was therefore suggested for the protection of the 15.65 kV isolation to install metal oxide surge arresters at a suitable place between the power generator bus bars and earthing.

  19. KV7 potassium channels

    DEFF Research Database (Denmark)

    Stott, Jennifer B; Jepps, Thomas Andrew; Greenwood, Iain A

    2014-01-01

    Potassium channels are key regulators of smooth muscle tone, with increases in activity resulting in hyperpolarisation of the cell membrane, which acts to oppose vasoconstriction. Several potassium channels exist within smooth muscle, but the KV7 family of voltage-gated potassium channels have been...

  20. Lightning in hybrid cable-overhead lines and consequent transient overvoltages

    DEFF Research Database (Denmark)

    Silva, Filipe Miguel Faria da; Schultz Pedersen, Kasper; Bak, Claus Leth

    2017-01-01

    Whereas lines that consist entirely of underground cable are naturally protected from lightning, the phenomenon must be considered for lines that are a mix of overhead lines and underground cables. The difference between overhead lines and underground cables wave impedances may lead to transient ...... conductor and for hits on the earth wire, with and without back flashover. For the most common situation, stroke on the earth wire, it is demonstrated that the cable’s ground propagation mode is dominant, reducing the impact of the reflections....

  1. Manitoba Hydro long-term high-voltage transmission line magnetic field monitoring project

    International Nuclear Information System (INIS)

    Wong, P.S.; Ng, C.K.

    2008-01-01

    As part of the licensing process to construct a new 230 kV transmission line on an existing right-of-way in Manitoba, an electrical effects study was conducted in 1998. The study was part of the environmental assessment program crucial in obtaining government approval to construct the line. Some residents living adjacent to the new transmission circuit expressed concerns about alleged adverse health effects associated with long-term exposure to magnetic fields from high voltage transmission lines. In order to verify the accuracy of the predicted magnetic field levels submitted to the regulatory body in the the electrical effects study and to instill confidence in the residents of the affected communities, a three-year magnetic monitoring project was conducted between 2003 and 2005 along the right-of-way after the new 230kV transmission line was energized by Manitoba Hydro. This paper described the monitoring program, with reference to location; equipment; data analysis; and discussion of results. It was concluded that the long-term monitoring project demonstrated that the magnetic field prediction methodology was well understood and accurate, and provided valuable long-term magnetic field characteristics at the edge of the right-of-way. In addition, when there is opposition to a transmission line, public consultation and education were found to be the best options to arrive at a solution. 3 refs., 1 tab., 12 figs

  2. Regulation of KV channel voltage-dependent activation by transmembrane β subunits

    Directory of Open Access Journals (Sweden)

    Xiaohui eSun

    2012-04-01

    Full Text Available Voltage-activated K+ (KV channels are important for shaping action potentials and maintaining resting membrane potential in excitable cells. KV channels contain a central pore-gate domain (PGD surrounded by four voltage-sensing domains (VSD. The VSDs will change conformation in response to alterations of the membrane potential thereby inducing the opening of the PGD. Many KV channels are heteromeric protein complexes containing auxiliary β subunits. These β subunits modulate channel expression and activity to increase functional diversity and render tissue specific phenotypes. This review focuses on the KV β subunits that contain transmembrane (TM segments including the KCNE family and the β subunits of large conductance, Ca2+- and voltage-activated K+ (BK channels. These TM β subunits affect the voltage-dependent activation of KV α subunits. Experimental and computational studies have described the structural location of these β subunits in the channel complexes and the biophysical effects on VSD activation, PGD opening and VSD-PGD coupling. These results reveal some common characteristics and mechanistic insights into KV channel modulation by TM β subunits.

  3. Fault and load flows analysis of electricity transmission and distribution system in Casanare (Colombia)

    OpenAIRE

    Castro-Galeano, Juan Carlos; Cabra-Sarmiento, Wilson Javier; Ortiz-Portilla, Jhony Fernando

    2017-01-01

    Abstract This article describes a simulation of the electrical local distribution and regional transmission system of Enerca S.A. E.S.P. at 34.5 kV and 115 kV, identifying the most critical circuits and substations. The company is located in one of the major petroleum production areas in Colombia, and because of a massive growth in this sector, the electrical company expanded its networks in a radial way. This expansion was improvised and poorly planned due to the accelerated need to meet the...

  4. Molecular and functional characterization of Kv7 K+ channel in murine gastrointestinal smooth muscles

    DEFF Research Database (Denmark)

    Jepps, Thomas Andrew; Greenwood, Iain A; Moffatt, James D

    2009-01-01

    that K(v)7.x especially K(v)7.4 and K(v)7.5 are expressed in different regions of the murine gastrointestinal tract and blockers of K(v)7 channels augment inherent contractile activity. Drugs that selectively block K(v)7.4/7.5 might be promising therapeutics for the treatment of motility disorders...

  5. High Voltage Power Transmission for Wind Energy

    Science.gov (United States)

    Kim, Young il

    The high wind speeds and wide available area at sea have recently increased the interests on offshore wind farms in the U.S.A. As offshore wind farms become larger and are placed further from the shore, the power transmission to the onshore grid becomes a key feature. Power transmission of the offshore wind farm, in which good wind conditions and a larger installation area than an onshore site are available, requires the use of submarine cable systems. Therefore, an underground power cable system requires unique design and installation challenges not found in the overhead power cable environment. This paper presents analysis about the benefit and drawbacks of three different transmission solutions: HVAC, LCC/VSC HVDC in the grid connecting offshore wind farms and also analyzed the electrical characteristics of underground cables. In particular, loss of HV (High Voltage) subsea power of the transmission cables was evaluated by the Brakelmann's theory, taking into account the distributions of current and temperature.

  6. The importance of immunohistochemical analyses in evaluating the phenotype of Kv channel knockout mice.

    Science.gov (United States)

    Menegola, Milena; Clark, Eliana; Trimmer, James S

    2012-06-01

    To gain insights into the phenotype of voltage-gated potassium (Kv)1.1 and Kv4.2 knockout mice, we used immunohistochemistry to analyze the expression of component principal or α subunits and auxiliary subunits of neuronal Kv channels in knockout mouse brains. Genetic ablation of the Kv1.1 α subunit did not result in compensatory changes in the expression levels or subcellular distribution of related ion channel subunits in hippocampal medial perforant path and mossy fiber nerve terminals, where high levels of Kv1.1 are normally expressed. Genetic ablation of the Kv4.2 α subunit did not result in altered neuronal cytoarchitecture of the hippocampus. Although Kv4.2 knockout mice did not exhibit compensatory changes in the expression levels or subcellular distribution of the related Kv4.3 α subunit, we found dramatic decreases in the cellular and subcellular expression of specific Kv channel interacting proteins (KChIPs) that reflected their degree of association and colocalization with Kv4.2 in wild-type mouse and rat brains. These studies highlight the insights that can be gained by performing detailed immunohistochemical analyses of Kv channel knockout mouse brains. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.

  7. Analysis of the 35 KV substation secondary system

    Science.gov (United States)

    Zhao, Yong; Jiang, Jianguo; Jiang, Chunlei; Ren, Shuang; Liu, Songbin

    2017-04-01

    This paper analyzes the status of the two system of some 35KV users' substation in Daqing oil field, the deficiencies of the two system of the existing 35KV substation are found out. And put forward the opinion of acceptance in the future work. I hope it can able to work in the future on the protection of professional help.

  8. High power thyristors with 5 kV blocking voltage. Volume 1: Development of high-voltage-thyristors (4.5 kV) with good dynamic properties

    Science.gov (United States)

    Lock, K.; Patalong, H.; Platzoeder, K.

    1979-01-01

    Using neutron irradiated silicon with considerably lower spread in resistivity as compared to conventionally doped silicon it was possible to produce power thyristors with breakdown voltages between 3.5 kV and 5.5 kV. The thyristor pellets have a diameter of 50 mm. Maximum average on-state currents of 600 to 800 A can be reached with these elements. The dynamic properties of the thryistors could be improved to allow standard applications up to maximum repetitive voltages of 4.5 kV.

  9. Joint HVAC transmission EMF environmental study

    Energy Technology Data Exchange (ETDEWEB)

    Stormshak, F.; Thompson, J. (Oregon State Univ., Corvallis, OR (United States))

    1992-05-01

    This document describes the rationale, procedures, and results of a carefully controlled study conducted to establish whether chronic exposure of female (ewe) Suffolk lambs to the environment of a 500-kV 60-Hz transmission line would affect various characteristics of growth, endocrine function, and reproductive development. This experiment used identical housing and management schemes for control and line-exposed ewes, thus minimizing these factors as contributors to between-group experimental error. Further, throughout the 10-month duration of this study, changes in electric and magnetic fields, audible noise, and weather conditions were monitored continuously by a computerized system. Such measurements provided the opportunity to identify any relationship between environmental factors and biological responses. Because of reports in the literature that electric and magnetic fields alter concentrations of melatonin in laboratory animals, the primary objective of this study was to ascertain whether a similar effect occurs in lambs exposed to a 500-kV a-c line in a natural setting. In addition, onset of puberty, changes in body weight, wool growth, and behavior were monitored. To determine whether the environment of a 500-kV line caused stress in the study animals, serum levels of cortisol were measured. The study was conducted at Bonneville Power Administration's Ostrander Substation near Estacada, Oregon.

  10. Improvement the Capacity of Cockcroft-Walton High Voltage Source from 300 kV/20 mA to 500 kV/20 mA for Accelerating Voltage of Electron Beam Machine

    International Nuclear Information System (INIS)

    Suprapto; Djasiman

    2002-01-01

    The improvement capacity of Cockcroft-Walton high voltage source from 300 kV/20 mA to 500 kV/mA has been carrying out. To improve the capacity of high voltage source was done by means of increasing the stage number of voltage multiplier from 11 to 18 and its output voltage measuring resistance. Each stage of voltage multiplier consists of 2 capacitors and 2 circuits of high voltage diode. This voltage multiplier is constructed using main components of high voltage capacitor and high voltage diode each of 0.22 μF/50 kV and UF 5408 respectively. To avoid stray discharge and corona it was provided with high voltage electrode and corona ring. The test result indicated that the output voltage obtained from 16 stages was 350 kV according to operating condition of 25 MΩ resistive load and first stage voltage of 28.5 kV with oscillator frequency of 24 Hz. That condition requires anode voltage and current of 5.5 kV and 2.5 A respectively. The no load test for 16 stages indicates 400 kV of output voltage and 28.5 kV first stage voltage. Efficiency of high voltage source was 48 % at 6.75 kW of output power. The expected test of 500 kV with 18 stages of voltage multiplier can not be carried out because of some restrictive of loading system. From the test result can be predicted that the output voltage of 500 kV with 18 stages of voltage multiplier requires 31.2 kV of first stage voltage. Then the expected high voltage source of Cockcroft-Walton is capable as accelerating voltage source for Electron Beam Machine with energy of 500 kV. (author)

  11. Damping of cable vibrations in overhead lines. Daempfung von Leiterseilschwingungen in Hochspannungs-Freileitungen

    Energy Technology Data Exchange (ETDEWEB)

    Moecks, L

    1981-01-01

    The 'Stockbridge'-type vibration damper is presented and its dynamic characteristics are analytically described. In consideration of standard line data a dynamic model of the overhead line is designed. The vibration impulse by the wind and self-damping of the cable are explained with relations being deduced. The entire mathematical model 'overhead line with and without damper' is finally forming the basis for performing numerous parameter studies, with the importance of the damper characteristics and the damper installation site to the value of the dynamic load of the cable being shown very clearly. The presented technique is also convenient for checking the vibration intensity of overhead lines to be newly planned.

  12. Retigabine, a Kv7.2/Kv7.3-Channel Opener, Attenuates Drug-Induced Seizures in Knock-In Mice Harboring Kcnq2 Mutations.

    Science.gov (United States)

    Ihara, Yukiko; Tomonoh, Yuko; Deshimaru, Masanobu; Zhang, Bo; Uchida, Taku; Ishii, Atsushi; Hirose, Shinichi

    2016-01-01

    The hetero-tetrameric voltage-gated potassium channel Kv7.2/Kv7.3, which is encoded by KCNQ2 and KCNQ3, plays an important role in limiting network excitability in the neonatal brain. Kv7.2/Kv7.3 dysfunction resulting from KCNQ2 mutations predominantly causes self-limited or benign epilepsy in neonates, but also causes early onset epileptic encephalopathy. Retigabine (RTG), a Kv7.2/ Kv7.3-channel opener, seems to be a rational antiepileptic drug for epilepsies caused by KCNQ2 mutations. We therefore evaluated the effects of RTG on seizures in two strains of knock-in mice harboring different Kcnq2 mutations, in comparison to the effects of phenobarbital (PB), which is the first-line antiepileptic drug for seizures in neonates. The subjects were heterozygous knock-in mice (Kcnq2Y284C/+ and Kcnq2A306T/+) bearing the Y284C or A306T Kcnq2 mutation, respectively, and their wild-type (WT) littermates, at 63-100 days of age. Seizures induced by intraperitoneal injection of kainic acid (KA, 12mg/kg) were recorded using a video-electroencephalography (EEG) monitoring system. Effects of RTG on KA-induced seizures of both strains of knock-in mice were assessed using seizure scores from a modified Racine's scale and compared with those of PB. The number and total duration of spike bursts on EEG and behaviors monitored by video recording were also used to evaluate the effects of RTG and PB. Both Kcnq2Y284C/+ and Kcnq2A306T/+ mice showed significantly more KA-induced seizures than WT mice. RTG significantly attenuated KA-induced seizure activities in both Kcnq2Y284C/+ and Kcnq2A306T/+ mice, and more markedly than PB. This is the first reported evidence of RTG ameliorating KA-induced seizures in knock-in mice bearing mutations of Kcnq2, with more marked effects than those observed with PB. RTG or other Kv7.2-channel openers may be considered as first-line antiepileptic treatments for epilepsies resulting from KCNQ2 mutations.

  13. Use of Overhead Transparencies in Collaborative Business Writing.

    Science.gov (United States)

    Barker, Randolph T.; And Others

    1991-01-01

    Asserts that small group collaborative writing exercises that produce overhead transparencies for large class critique can be an effective method for teaching letter and memorandum construction. Offers a five-step process for encouraging individual and collaborative writing skills. (PRA)

  14. Long-distance power transmission technology. Microwave power transmission; Denryoku no chokyori yuso gijutsu. Micro ha musen soden

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, N [Kobe University, Kobe (Japan). Faculty of Engineering

    1994-11-05

    This paper explains the principles of microwave power transmission as a long-distance power transmission technology, and the status of its development. Under an assumption of using a wave length of 12 cm (2.45 GHz) and a transmission distance of 1 km, an ideal wireless power transmission can realize transmitting the power at an efficiency of 95% or higher if transmitting and receiving antennas with a radius of 8.8 m are used. What remains as important requirements is raising the efficiency of conversion from power supply into microwaves, and the efficiency of rectification after the power has been received. By using microwave energy sent from a transmission antenna installed on the roof of an automobile, a model airplane with a receiving antenna installed at its rear flew successfully for 40 seconds under the microwave lifted airplane experiment (MILAX). In an experiment of transmitting microwave power in space, power was successfully transmitted to the child rocket as an event under the International Space Year - Microwave Energy Transmission in Space (ISY-METS). The microwave wireless power transmission on the ground would have a possibility of taking over the overhead line transmission into islands. An attempt is scheduled to send power of 5 kW by using transmission and receiving antennas with a diameter of 3 m to investigate effects on transmission efficiency, and communications and electromagnetic environments, and to collect basic data. 3 refs., 3 figs.

  15. Proximity to overhead power lines and childhood leukaemia

    DEFF Research Database (Denmark)

    Amoon, Aryana T; Crespi, Catherine M; Ahlbom, Anders

    2018-01-01

    BACKGROUND: Although studies have consistently found an association between childhood leukaemia risk and magnetic fields, the associations between childhood leukaemia and distance to overhead power lines have been inconsistent. We pooled data from multiple studies to assess the association with d...

  16. Development and use of 60 kV, and 150 kV floating deck modulators for high voltage protection of multi-megawatt ion beam accelerators

    International Nuclear Information System (INIS)

    Barber, G.C.; Ponte, N.S.; Schilling, G.

    1977-01-01

    Extraction currents of 60 A at 40 kV have been produced by utilizing a 60 kV floating deck modulator interfaced to a high voltage power supply. The modulator is operated in a series mode to repetitively pulse power to the ion beam accelerator. Current monitoring and other protective circuits provide interrupt commands to the series switch tube when faults occur. The constant current characteristics of the water cooled tetrode and the rapid response of the protective circuits effectively limit the fault energy to the ion source. Three of the 60 kV decks have been modified and stacked in a series configuration to supply 150 kV, 50 A pulses. This system supplies power for development of higher-energy multi-grid sources. In this system attention has been focused on forced voltage sharing of the three decks and on protective circuits for fault conditions. All control signal processing and conditioning is performed at ground level. Fiber optic links are used to interface with the high potential associated with the floating decks. A shunt modulator incorporated with this system provides regulation of the voltage to the ion source gradient grid. Future modulator development includes a system to deliver 100 A at 80 kV

  17. Expression and function of K(V)2-containing channels in human urinary bladder smooth muscle.

    Science.gov (United States)

    Hristov, Kiril L; Chen, Muyan; Afeli, Serge A Y; Cheng, Qiuping; Rovner, Eric S; Petkov, Georgi V

    2012-06-01

    The functional role of the voltage-gated K(+) (K(V)) channels in human detrusor smooth muscle (DSM) is largely unexplored. Here, we provide molecular, electrophysiological, and functional evidence for the expression of K(V)2.1, K(V)2.2, and the electrically silent K(V)9.3 subunits in human DSM. Stromatoxin-1 (ScTx1), a selective inhibitor of K(V)2.1, K(V)2.2, and K(V)4.2 homotetrameric channels and of K(V)2.1/9.3 heterotetrameric channels, was used to examine the role of these channels in human DSM function. Human DSM tissues were obtained during open bladder surgeries from patients without a history of overactive bladder. Freshly isolated human DSM cells were studied using RT-PCR, immunocytochemistry, live-cell Ca(2+) imaging, and the perforated whole cell patch-clamp technique. Isometric DSM tension recordings of human DSM isolated strips were conducted using tissue baths. RT-PCR experiments showed mRNA expression of K(V)2.1, K(V)2.2, and K(V)9.3 (but not K(V)4.2) channel subunits in human isolated DSM cells. K(V)2.1 and K(V)2.2 protein expression was confirmed by Western blot analysis and immunocytochemistry. Perforated whole cell patch-clamp experiments revealed that ScTx1 (100 nM) inhibited the amplitude of the voltage step-induced K(V) current in freshly isolated human DSM cells. ScTx1 (100 nM) significantly increased the intracellular Ca(2+) level in DSM cells. In human DSM isolated strips, ScTx1 (100 nM) increased the spontaneous phasic contraction amplitude and muscle force, and enhanced the amplitude of the electrical field stimulation-induced contractions within the range of 3.5-30 Hz stimulation frequencies. These findings reveal that ScTx1-sensitive K(V)2-containing channels are key regulators of human DSM excitability and contractility and may represent new targets for pharmacological or genetic intervention for bladder dysfunction.

  18. 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...

  19. Sliceable transponders for metro-access transmission links

    Science.gov (United States)

    Wagner, C.; Madsen, P.; Spolitis, S.; Vegas Olmos, J. J.; Tafur Monroy, I.

    2015-01-01

    This paper presents a solution for upgrading optical access networks by reusing existing electronics or optical equipment: sliceable transponders using signal spectrum slicing and stitching back method after direct detection. This technique allows transmission of wide bandwidth signals from the service provider (OLT - optical line terminal) to the end user (ONU - optical network unit) over an optical distribution network (ODN) via low bandwidth equipment. We show simulation and experimental results for duobinary signaling of 1 Gbit/s and 10 Gbit/s waveforms. The number of slices is adjusted to match the lowest analog bandwidth of used electrical devices and scale from 2 slices to 10 slices. Results of experimental transmission show error free signal recovery by using post forward error correction with 7% overhead.

  20. On the use of programmable logical controllers (PLC) in the emergency control schemes for the 750 kV system

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Roberto Campos de; Oliveira, Mario Cesar Santos de [FURNAS, Rio de Janeiro, RJ (Brazil)

    1994-12-31

    The energy produced at the Itaipu Power Plant for the Brazilian Interconnected System is transmitted through two different transmission system: -HVDC system, with two bipoles of +- 600 kV, 6300 MW which connect the substation of Foz do Iguacu in the State of Parana, to substation of Ibiuna in the State of Sao Paulo, transmitting the energy generated in 50 Hz units. This system was entirely commissioned on september of 1987. (author) 3 refs., 5 figs.

  1. Deletion of the Kv2.1 delayed rectifier potassium channel leads to neuronal and behavioral hyperexcitability

    Science.gov (United States)

    Speca, David J.; Ogata, Genki; Mandikian, Danielle; Bishop, Hannah I.; Wiler, Steve W.; Eum, Kenneth; Wenzel, H. Jürgen; Doisy, Emily T.; Matt, Lucas; Campi, Katharine L.; Golub, Mari S.; Nerbonne, Jeanne M.; Hell, Johannes W.; Trainor, Brian C.; Sack, Jon T.; Schwartzkroin, Philip A.; Trimmer, James S.

    2014-01-01

    The Kv2.1 delayed rectifier potassium channel exhibits high-level expression in both principal and inhibitory neurons throughout the central nervous system, including prominent expression in hippocampal neurons. Studies of in vitro preparations suggest that Kv2.1 is a key yet conditional regulator of intrinsic neuronal excitability, mediated by changes in Kv2.1 expression, localization and function via activity-dependent regulation of Kv2.1 phosphorylation. Here we identify neurological and behavioral deficits in mutant (Kv2.1−/−) mice lacking this channel. Kv2.1−/− mice have grossly normal characteristics. No impairment in vision or motor coordination was apparent, although Kv2.1−/− mice exhibit reduced body weight. The anatomic structure and expression of related Kv channels in the brains of Kv2.1−/− mice appears unchanged. Delayed rectifier potassium current is diminished in hippocampal neurons cultured from Kv2.1−/− animals. Field recordings from hippocampal slices of Kv2.1−/− mice reveal hyperexcitability in response to the convulsant bicuculline, and epileptiform activity in response to stimulation. In Kv2.1−/− mice, long-term potentiation at the Schaffer collateral – CA1 synapse is decreased. Kv2.1−/− mice are strikingly hyperactive, and exhibit defects in spatial learning, failing to improve performance in a Morris Water Maze task. Kv2.1−/− mice are hypersensitive to the effects of the convulsants flurothyl and pilocarpine, consistent with a role for Kv2.1 as a conditional suppressor of neuronal activity. Although not prone to spontaneous seizures, Kv2.1−/− mice exhibit accelerated seizure progression. Together, these findings suggest homeostatic suppression of elevated neuronal activity by Kv2.1 plays a central role in regulating neuronal network function. PMID:24494598

  2. The performance of transmission lines and cables subjected to electromagnetic radiation from a nuclear explosion (NEMP)

    International Nuclear Information System (INIS)

    Aguet, M.; Ianovici, M.; Lin, C.C.; Fornerod, F.

    1980-01-01

    The use of armoured cables for telecommunication and data transmission systems is practically essential to avoid electromagnetic interference. The authors have made a mathematical study of the probable effect of a high altitude nuclear explosion. Using a simplified model, the voltages and currents induced into single and multiple-sheathed, overhead and buried cables subjected to an intense magnetic pulse (50kV/m) from high altitude, are determined by computer. It is found that, contrary to expectations the current intensity in the second case is seven times greater than for the overhead conductor. (F.N.S.)

  3. First multivendor scheme in CFE to protection of 400 kV transmission line, using optical TC's, digital relays and bus IEC 61850-9-2; Primer esquema multivendedor en CFE para proteccion de linea de transmision de 400 kV, utilizando TC's opticos, relevadores digitales y bus IEC 61850-9-2

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Colon, V.R; Rasgado, J.P [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Lara C, H; Melendez, C; Juarez, N [Subdireccion de Transmision, Comision Federal de Electricidad (Mexico)

    2013-03-15

    This paper presents the details of design, installation and putting into service in the Comision Federal de Electricidad (CFE), of the first multi-vendor scheme that exists in the world, for the protection of a 400kV transmission line, which uses optical current transformers and digital relays IEC 61850-9-2. This system arises as a pilot project of the Subdireccion de Transmision of the CFE with the Instituto de Investigaciones Electricas (IIE). To ensure success in the implementation of the protection scheme, CFE joined a team coordinated by the Instituto de Investigaciones Electricas (IIE)involving nine international companies and a university. Pilot protection scheme is in operation under continuous monitoring, in one of the transmission lines of CFE that interconnect Manuel Moreno Torres with El Juile substations. The construction features, the challenges that were overcome and the first results obtained in operation are presented below. [Spanish] Este articulo presenta los detalles del diseno, instalacion y puesta en servicio en la Comision Federal de Electricidad (CFE) del primer esquema multivendedor que existe en el mundo, para la proteccion de una linea de transmision de 400kV, que utiliza transformadores de corriente opticos y relevadores digitales IEC 61850-9-2. Este sistema surge como un proyecto piloto de la Subdireccion de Transmision de la CFE con el Instituto de Investigaciones Electricas (IIE). Para asegurar el exito en la implementacion del esquema de proteccion, la CFE integro un equipo de trabajo coordinado por el Instituto de Investigaciones Electricas (IIE) en el que participaron 9 empresas internacionales y una universidad. El esquema de proteccion piloto, se encuentra en operacion bajo monitoreo continuo, en una de las lineas de transmision de la CFE que interconecta las subestaciones de Manuel Moreno Torres y El Juile. Las caracteristicas de construccion, los retos que fueron vencidos y los primeros resultados obtenidos en su operacion se

  4. Application of distantiometric protections to 500 kV lines with AL 100% series compensation; Aplicacion de protecciones distanciometricas a lineas de 500 kV con compensacion serie AL 100%

    Energy Technology Data Exchange (ETDEWEB)

    Gaudio, Juan Carlos; Pesce, Jose Juan O.; Faure, Carlos Hugo [TRANSENER S.A., Buenos Aires (Argentina)

    2001-07-01

    The TRANSENER S.A. viewing the rising of the transmission capacity of the Northeastern Argentine Generators, assumed the installation costs of compensation by series capacitors. In the middle of the year 2000 was put into service a series capacitor bank on the extremity Recreo of the 500 kV to the Malvinas Argentina of the TRANSENER S.A.. The reactance compensation of the line in about 100% was responsible by the necessity of replacing the existent analogic electronic protection by new numerical distantiometric protections on the El Bracho and Malvinas Argentinas transformer station. This paper presents the imposed conditions for the selected line protection, the prior studies posterior the mentioned selection for validating the application, and the difficulties necessary to the task performing as well.

  5. Rehabilitation of the Overhead Athlete’s Elbow

    Science.gov (United States)

    Wilk, Kevin E.; Macrina, Leonard C.; Cain, E. Lyle; Dugas, Jeffrey R.; Andrews, James R.

    2012-01-01

    The activities required during overhead sports, particularly during baseball pitching, produce large forces at the elbow joint. Injuries to the elbow joint frequently occur in the overhead athlete because of the large amount of forces observed during the act of throwing, playing tennis, or playing golf. Injuries may result because of repetitive overuse, leading to tissue failure. Rehabilitation following injury or surgery to the throwing elbow is vital to fully restore normal function and return the athlete to competition as quickly and safely as possible. Rehabilitation of the elbow, whether following injury or postsurgical, must follow a progressive and sequential order, building on the previous phase, to ensure that healing tissues are not compromised. Emphasis is placed on restoring full motion, muscular strength, and neuromuscular control while gradually applying loads to healing tissue. In addition, when one is creating a rehabilitation plan for athletes, it is imperative to treat the entire upper extremity, core, and legs to create and dissipate the forces generated at each joint. PMID:23016113

  6. The development of a 200 kV monochromated field emission electron source

    Energy Technology Data Exchange (ETDEWEB)

    Mukai, Masaki, E-mail: mmukai@jeol.co.jp [JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558 (Japan); Kim, Judy S. [University of Oxford, Department of Materials, Parks Road, Oxford, OX1 3PH (United Kingdom); Omoto, Kazuya; Sawada, Hidetaka; Kimura, Atsushi; Ikeda, Akihiro; Zhou, Jun; Kaneyama, Toshikatsu [JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558 (Japan); Young, Neil P.; Warner, Jamie H.; Nellist, Peter D.; Kirkland, Angus I. [University of Oxford, Department of Materials, Parks Road, Oxford, OX1 3PH (United Kingdom)

    2014-05-01

    We report the development of a monochromator for an intermediate-voltage aberration-corrected electron microscope suitable for operation in both STEM and TEM imaging modes. The monochromator consists of two Wien filters with a variable energy selecting slit located between them and is located prior to the accelerator. The second filter cancels the energy dispersion produced by the first filter and after energy selection forms a round monochromated, achromatic probe at the specimen plane. The ultimate achievable energy resolution has been measured as 36 meV at 200 kV and 26 meV at 80 kV. High-resolution Annular Dark Field STEM images recorded using a monochromated probe resolve Si–Si spacings of 135.8 pm using energy spreads of 218 meV at 200 kV and 217 meV at 80 kV respectively. In TEM mode an improvement in non-linear spatial resolution to 64 pm due to the reduction in the effects of partial temporal coherence has been demonstrated using broad beam illumination with an energy spread of 134 meV at 200 kV. - Highlights: • Monochromator for 200 kV aberration corrected TEM and STEM was developed. • Monochromator produces monochromated and achromatic probe at specimen plane. • Ultimate energy resolution was measured to be 36 meV at 200 kV and 26 meV at 80 kV. • Atomic resolution STEM images were recorded using monochromated electron probe. • Improvements of TEM resolution were confirmed using monochromated illumination.

  7. The development of a 200 kV monochromated field emission electron source

    International Nuclear Information System (INIS)

    Mukai, Masaki; Kim, Judy S.; Omoto, Kazuya; Sawada, Hidetaka; Kimura, Atsushi; Ikeda, Akihiro; Zhou, Jun; Kaneyama, Toshikatsu; Young, Neil P.; Warner, Jamie H.; Nellist, Peter D.; Kirkland, Angus I.

    2014-01-01

    We report the development of a monochromator for an intermediate-voltage aberration-corrected electron microscope suitable for operation in both STEM and TEM imaging modes. The monochromator consists of two Wien filters with a variable energy selecting slit located between them and is located prior to the accelerator. The second filter cancels the energy dispersion produced by the first filter and after energy selection forms a round monochromated, achromatic probe at the specimen plane. The ultimate achievable energy resolution has been measured as 36 meV at 200 kV and 26 meV at 80 kV. High-resolution Annular Dark Field STEM images recorded using a monochromated probe resolve Si–Si spacings of 135.8 pm using energy spreads of 218 meV at 200 kV and 217 meV at 80 kV respectively. In TEM mode an improvement in non-linear spatial resolution to 64 pm due to the reduction in the effects of partial temporal coherence has been demonstrated using broad beam illumination with an energy spread of 134 meV at 200 kV. - Highlights: • Monochromator for 200 kV aberration corrected TEM and STEM was developed. • Monochromator produces monochromated and achromatic probe at specimen plane. • Ultimate energy resolution was measured to be 36 meV at 200 kV and 26 meV at 80 kV. • Atomic resolution STEM images were recorded using monochromated electron probe. • Improvements of TEM resolution were confirmed using monochromated illumination

  8. Modeling-independent elucidation of inactivation pathways in recombinant and native A-type Kv channels

    Science.gov (United States)

    Fineberg, Jeffrey D.; Ritter, David M.

    2012-01-01

    A-type voltage-gated K+ (Kv) channels self-regulate their activity by inactivating directly from the open state (open-state inactivation [OSI]) or by inactivating before they open (closed-state inactivation [CSI]). To determine the inactivation pathways, it is often necessary to apply several pulse protocols, pore blockers, single-channel recording, and kinetic modeling. However, intrinsic hurdles may preclude the standardized application of these methods. Here, we implemented a simple method inspired by earlier studies of Na+ channels to analyze macroscopic inactivation and conclusively deduce the pathways of inactivation of recombinant and native A-type Kv channels. We investigated two distinct A-type Kv channels expressed heterologously (Kv3.4 and Kv4.2 with accessory subunits) and their native counterparts in dorsal root ganglion and cerebellar granule neurons. This approach applies two conventional pulse protocols to examine inactivation induced by (a) a simple step (single-pulse inactivation) and (b) a conditioning step (double-pulse inactivation). Consistent with OSI, the rate of Kv3.4 inactivation (i.e., the negative first derivative of double-pulse inactivation) precisely superimposes on the profile of the Kv3.4 current evoked by a single pulse because the channels must open to inactivate. In contrast, the rate of Kv4.2 inactivation is asynchronous, already changing at earlier times relative to the profile of the Kv4.2 current evoked by a single pulse. Thus, Kv4.2 inactivation occurs uncoupled from channel opening, indicating CSI. Furthermore, the inactivation time constant versus voltage relation of Kv3.4 decreases monotonically with depolarization and levels off, whereas that of Kv4.2 exhibits a J-shape profile. We also manipulated the inactivation phenotype by changing the subunit composition and show how CSI and CSI combined with OSI might affect spiking properties in a full computational model of the hippocampal CA1 neuron. This work unambiguously

  9. Overhead remote handling systems for the process facility modifications project

    International Nuclear Information System (INIS)

    Wiesener, R.W.; Grover, D.L.

    1987-01-01

    Each of the cells in the process facility modifications (PFM) project complex is provided with a variety of general purpose remote handling equipment including bridge cranes, monorail hoist, bridge-mounted electromechanical manipulator (EMM) and an overhead robot used for high efficiency particulate air (HEPA) filter changeout. This equipment supplements master-slave manipulators (MSMs) located throughout the complex to provide an overall remote handling system capability. The overhead handling equipment is used for fuel and waste material handling operations throughout the process cells. The system also provides the capability for remote replacement of all in-cell process equipment which may fail or be replaced for upgrading during the lifetime of the facility

  10. Shoulder injuries in overhead sports; Schultergelenkverletzungen bei Ueberkopfsportarten

    Energy Technology Data Exchange (ETDEWEB)

    Woertler, K. [Technische Universitaet Muenchen (Germany). Institut fuer Roentgendiagnostik

    2010-05-15

    Overhead sport places great demands on the shoulder joint. Shoulder pain in overhead athletes and throwers can in the majority of cases be attributed to lesions resulting from chronic overuse of tendons and capsuloligamentous structures or to sequels of microinstability and secondary impingement. Due to its great impact on therapeutic decisions, imaging in athletes with unclear shoulder pain is a challenge. In this connection, magnetic resonance (MR) arthrography represents the cross-sectional imaging modality of first choice, as it allows depiction and exclusion of pathologic alterations of all relevant joint structures with sufficient confidence. This article reviews the biomechanical and clinical aspects and MR arthrographic features of the most common shoulder pathologies in overhead athletes, including biceps tendinopathy, superior labral anterior-posterior (SLAP) lesions, rotator cuff lesions, as well as extrinsic and intrinsic impingement syndromes. (orig.) [German] Ueberkopfsportarten stellen grosse Anforderungen an das Schultergelenk. Schulterbeschwerden bei Ueberkopf- und Wurfsportlern koennen in der Mehrzahl der Faelle auf eine chronische Ueberlastung von Sehnen und Kapsel-Band-Strukturen oder auf die Folgen einer Mikroinstabilitaet und sekundaerer Impingementsyndrome zurueckgefuehrt werden. Wegen ihres grossen Einflusses auf die Therapieentscheidung stellt die Bildgebung bei Athleten mit unklaren Schulterbeschwerden eine Herausforderung dar. Die MR-Arthrographie ist in diesem Zusammenhang als Schnittbildverfahren der ersten Wahl anzusehen, da sie den Nachweis bzw. Ausschluss pathologischer Veraenderungen aller relevanten Gelenkstrukturen mit ausreichender Sicherheit ermoeglicht. Dieser Artikel gibt eine Uebersicht ueber biomechanische und klinische Aspekte sowie MR-arthrographische Befunde der haeufigsten Schultergelenkpathologien bei Ueberkopfsportlern, wie Bizepstendinopathie, Superior-labral-anterior-posterior- (SLAP-)Laesionen, Laesionen der

  11. KCNE1 constrains the voltage sensor of Kv7.1 K+ channels.

    Directory of Open Access Journals (Sweden)

    Liora Shamgar

    Full Text Available Kv7 potassium channels whose mutations cause cardiovascular and neurological disorders are members of the superfamily of voltage-gated K(+ channels, comprising a central pore enclosed by four voltage-sensing domains (VSDs and sharing a homologous S4 sensor sequence. The Kv7.1 pore-forming subunit can interact with various KCNE auxiliary subunits to form K(+ channels with very different gating behaviors. In an attempt to characterize the nature of the promiscuous gating of Kv7.1 channels, we performed a tryptophan-scanning mutagenesis of the S4 sensor and analyzed the mutation-induced perturbations in gating free energy. Perturbing the gating energetics of Kv7.1 bias most of the mutant channels towards the closed state, while fewer mutations stabilize the open state or the inactivated state. In the absence of auxiliary subunits, mutations of specific S4 residues mimic the gating phenotypes produced by co-assembly of Kv7.1 with either KCNE1 or KCNE3. Many S4 perturbations compromise the ability of KCNE1 to properly regulate Kv7.1 channel gating. The tryptophan-induced packing perturbations and cysteine engineering studies in S4 suggest that KCNE1 lodges at the inter-VSD S4-S1 interface between two adjacent subunits, a strategic location to exert its striking action on Kv7.1 gating functions.

  12. Sliceable Transponders for Metro-Access Transmission Links

    DEFF Research Database (Denmark)

    Wagner, Christoph; Madsen, P.; Spolitis, S.

    2015-01-01

    the service provider (OLT - optical line terminal) to the end user (ONU – optical network unit) over an optical distribution network (ODN) via low bandwidth equipment. We show simulation and experimental results for duobinary signaling of 1 Gbit/s and 10 Gbit/s waveforms. The number of slices is adjusted...... to match the lowest analog bandwidth of used electrical devices and scale from 2 slices to 10 slices. Results of experimental transmission show error free signal recovery by using post forward error correction with 7% overhead....

  13. Identification of a functional interaction between Kv4.3 channels and c-Src tyrosine kinase.

    Science.gov (United States)

    Gomes, Pedro; Saito, Tomoaki; Del Corsso, Cris; Alioua, Abderrahmane; Eghbali, Mansoureh; Toro, Ligia; Stefani, Enrico

    2008-10-01

    Voltage-gated K(+) (Kv) channels are key determinants of cardiac and neuronal excitability. A substantial body of evidence has accumulated in support of a role for Src family tyrosine kinases in the regulation of Kv channels. In this study, we examined the possibility that c-Src tyrosine kinase participates in the modulation of the transient voltage-dependent K(+) channel Kv4.3. Supporting a mechanistic link between Kv4.3 and c-Src, confocal microscopy analysis of HEK293 cells stably transfected with Kv4.3 showed high degree of co-localization of the two proteins at the plasma membrane. Our results further demonstrate an association between Kv4.3 and c-Src by co-immunoprecipitation and GST pull-down assays, this interaction being mediated by the SH2 and SH3 domains of c-Src. Furthermore, we show that Kv4.3 is tyrosine phosphorylated under basal conditions. The functional relevance of the observed interaction between Kv4.3 and c-Src was established in patch-clamp experiments, where application of the Src inhibitor PP2 caused a decrease in Kv4.3 peak current amplitude, but not the inactive structural analogue PP3. Conversely, intracellular application of recombinant c-Src kinase or the protein tyrosine phosphatase inhibitor bpV(phen) increased Kv4.3 peak current amplitude. In conclusion, our findings provide evidence that c-Src-induced Kv4.3 channel activation involves their association in a macromolecular complex and suggest a role for c-Src-Kv4.3 pathway in regulating cardiac and neuronal excitability.

  14. High power cable with internal water cooling 400 kV

    Science.gov (United States)

    Rasquin, W.; Harjes, B.

    1982-08-01

    Due to the concentration of electricity production in large power plants, the need of higher power transmissions, and the protection of environment, developement of a 400 kV water cooled cable in the power range of 1 to 5 GVA was undertaken. The fabrication and testing of equipment, engineering of cable components, fabrication of a test cable, development of cable terminal laboratory, testing of test cable, field testing of test cable, fabrication of industrial cable laboratory, testing of industrial cable, field testing of industrial cable, and system analysis for optimization were prepared. The field testing was impossible to realize. However, it is proved that a cable consisting of an internal stainless steel water cooled tube, covered by stranded copper profiles, insulated with heavy high quality paper, and protected by an aluminum cover can be produced, withstand tests accordingly to IEC/VDE recommendations, and is able to fulfill all exploitation conditions.

  15. RObust header compression (ROHC) performance for multimedia transmission over 3G/4G wireless networks

    DEFF Research Database (Denmark)

    Fitzek, Frank; Rein, S.; Seeling, P.

    2005-01-01

    Robust Header Compression (ROHC) has recently been proposed to reduce the large protocol header overhead when transmitting voice and other continuous meadi over IP based control stacks in wireless networks. In this paper we evaluate the real-time transmission of GSM encoded voice and H. 26L encod...

  16. Kv7.1 surface expression is regulated by epithelial cell polarization

    DEFF Research Database (Denmark)

    Andersen, Martin N; Olesen, Søren-Peter; Rasmussen, Hanne Borger

    2011-01-01

    The potassium channel K(V)7.1 is expressed in the heart where it contributes to the repolarization of the cardiac action potential. In addition, K(V)7.1 is expressed in epithelial tissues where it plays a role in salt and water transport. Mutations in the kcnq1 gene can lead to long QT syndrome...... and deafness, and several mutations have been described as trafficking mutations. To learn more about the basic mechanisms that regulate K(V)7.1 surface expression, we have investigated the trafficking of K(V)7.1 during the polarization process of the epithelial cell line Madin-Darby Canine Kidney (MDCK) using...... is regulated by signaling mechanisms involved in epithelial cell polarization in particular signaling cascades involving protein kinase C and PI3K....

  17. 78 FR 77027 - Overhead Clearance (Air-Draft) Accidents

    Science.gov (United States)

    2013-12-20

    ... No. USCG-2013-0466] Overhead Clearance (Air-Draft) Accidents AGENCY: Coast Guard, DHS. ACTION... clearance (air-draft) accidents. In its petition, which calls for vessel masters to be provided with... accidents that it says were avoidable and that resulted in damage to or destruction of waterway...

  18. The secret life of ion channels: Kv1.3 potassium channels and proliferation.

    Science.gov (United States)

    Pérez-García, M Teresa; Cidad, Pilar; López-López, José R

    2018-01-01

    Kv1.3 channels are involved in the switch to proliferation of normally quiescent cells, being implicated in the control of cell cycle in many different cell types and in many different ways. They modulate membrane potential controlling K + fluxes, sense changes in potential, and interact with many signaling molecules through their intracellular domains. From a mechanistic point of view, we can describe the role of Kv1.3 channels in proliferation with at least three different models. In the "membrane potential model," membrane hyperpolarization resulting from Kv1.3 activation provides the driving force for Ca 2+ influx required to activate Ca 2+ -dependent transcription. This model explains most of the data obtained from several cells from the immune system. In the "voltage sensor model," Kv1.3 channels serve mainly as sensors that transduce electrical signals into biochemical cascades, independently of their effect on membrane potential. Kv1.3-dependent proliferation of vascular smooth muscle cells (VSMCs) could fit this model. Finally, in the "channelosome balance model," the master switch determining proliferation may be related to the control of the Kv1.3 to Kv1.5 ratio, as described in glial cells and also in VSMCs. Since the three mechanisms cannot function independently, these models are obviously not exclusive. Nevertheless, they could be exploited differentially in different cells and tissues. This large functional flexibility of Kv1.3 channels surely gives a new perspective on their functions beyond their elementary role as ion channels, although a conclusive picture of the mechanisms involved in Kv1.3 signaling to proliferation is yet to be reached.

  19. The role of handouts, note-taking and overhead transparencies in veterinary science lectures.

    Science.gov (United States)

    McLennan, M W; Isaacs, G

    2002-10-01

    To study student and staff views of the role and use of handouts, note-taking and overhead transparencies in veterinary science lectures at the University of Queensland The Nominal Group Technique was used to help develop a questionnaire, which was completed by 351 students (a response rate of 84%) and 35 staff (76%) from the 5 years of the veterinary course. The data were analysed using the SAS statistical computer package. Staff and students held different views as to the frequency with which handouts should be used, their educational value, and whether they should be complete or partial. Fewer students than staff agreed that handouts discourage further reading in a subject. Almost all staff and students saw the central functions of note-taking to be provision of notes for subsequent revision and encoding information given by the lecturer. More students than staff however, considered that note-taking in lectures interferes with understanding. Staff and students held similar views as to the uses of overheads in lectures. Interestingly however, more staff than students agreed that overheads often contain too much information. Both students and staff saw the central role of note-taking as providing a set of good notes for revision. Generally students preferred that this information be provided in the form of partial or complete handouts, while staff preferred students to take notes and to read outside lectures. Surprisingly, more staff than students felt that overhead transparencies often contained too much information. Note-taking, handouts and overhead transparencies need to be linked in a coherent educational strategy to promote effective learning.

  20. Blockade of the voltage-gated potassium channel Kv1.3 inhibits immune responses in vivo.

    Science.gov (United States)

    Koo, G C; Blake, J T; Talento, A; Nguyen, M; Lin, S; Sirotina, A; Shah, K; Mulvany, K; Hora, D; Cunningham, P; Wunderler, D L; McManus, O B; Slaughter, R; Bugianesi, R; Felix, J; Garcia, M; Williamson, J; Kaczorowski, G; Sigal, N H; Springer, M S; Feeney, W

    1997-06-01

    The voltage activated K+ channel (Kv1.3) has recently been identified as the molecule that sets the resting membrane potential of peripheral human T lymphoid cells. In vitro studies indicate that blockage of Kv1.3 inhibits T cell activation, suggesting that Kv1.3 may be a target for immunosuppression. However, despite the in vitro evidence, there has been no in vivo demonstration that blockade of Kv1.3 will attenuate an immune response. The difficulty is due to species differences, as the channel does not set the membrane potential in rodent peripheral T cells. In this study, we show that the channel is present on peripheral T cells of miniswine. Using the peptidyl Kv1.3 inhibitor, margatoxin, we demonstrate that Kv1.3 also regulates the resting membrane potential, and that blockade of Kv1.3 inhibits, in vivo, both a delayed-type hypersensitivity reaction and an Ab response to an allogeneic challenge. In addition, prolonged Kv1.3 blockade causes reduced thymic cellularity and inhibits the thymic development of T cell subsets. These results provide in vivo evidence that Kv1.3 is a novel target for immunomodulation.

  1. 78 FR 68477 - Overhead and Gantry Cranes; Extension of the Office of Management and Budget's (OMB) Approval of...

    Science.gov (United States)

    2013-11-14

    ...] Overhead and Gantry Cranes; Extension of the Office of Management and Budget's (OMB) Approval of... requirements specified in the Standard on Overhead and Gantry Cranes (29 CFR 1910.179). DATES: Comments must be... information (29 U.S.C. 657). The paperwork provisions of the Standard on Overhead and Gantry Cranes specify...

  2. The design, construction, and operation of long-distance high-voltage electricity transmission technologies.

    Energy Technology Data Exchange (ETDEWEB)

    Molburg, J. C.; Kavicky, J. A.; Picel, K. C.

    2008-03-03

    This report focuses on transmission lines, which operate at voltages of 115 kV and higher. Currently, the highest voltage lines comprising the North American power grid are at 765 kV. The grid is the network of transmission lines that interconnect most large power plants on the North American continent. One transmission line at this high voltage was built near Chicago as part of the interconnection for three large nuclear power plants southwest of the city. Lines at this voltage also serve markets in New York and New England, also very high demand regions. The large power transfers along the West Coast are generally at 230 or 500 kV. Just as there are practical limits to centralization of power production, there are practical limits to increasing line voltage. As voltage increases, the height of the supporting towers, the size of the insulators, the distance between conductors on a tower, and even the width of the right-of-way (ROW) required increase. These design features safely isolate the electric power, which has an increasing tendency to arc to ground as the voltage (or electrical potential) increases. In addition, very high voltages (345 kV and above) are subject to corona losses. These losses are a result of ionization of the atmosphere, and can amount to several megawatts of wasted power. Furthermore, they are a local nuisance to radio transmission and can produce a noticeable hum. Centralized power production has advantages of economies of scale and special resource availability (for instance, hydro resources), but centralized power requires long-distance transfers of power both to reach customers and to provide interconnections for reliability. Long distances are most economically served at high voltages, which require large-scale equipment and impose a substantial footprint on the corridors through which power passes. The most visible components of the transmission system are the conductors that provide paths for the power and the towers that keep these

  3. Innovative multi system traction equipment for modern rail vehicles; Innovative Mehrsystem-Antriebsausruestung fuer moderne Triebzuege

    Energy Technology Data Exchange (ETDEWEB)

    Guggisberg, B.; Daehler, P. [ABB Schweiz AG, Turgi (Switzerland)

    2007-07-01

    The BORDLINE-Compact Converter consists of a main traction converter with integrated auxiliary converter. The converters are equipped with low voltage semiconductors and are intended to be used in DMUs as well as in EMUs with overhead voltages of 15 kV or 25 kV. For the operation with 3 kV DC an additional DC to AC converter using a separate main transformer winding is installed. (orig.)

  4. PKC and AMPK regulation of Kv1.5 potassium channels

    DEFF Research Database (Denmark)

    Andersen, Martin Nybo; Skibsbye, Lasse; Tang, Chuyi

    2015-01-01

    The voltage-gated Kv1.5 potassium channel, conducting the ultra-rapid rectifier K(+) current (IKur), is regulated through several pathways. Here we investigate if Kv1.5 surface expression is controlled by the 2 kinases PKC and AMPK, using Xenopus oocytes, MDCK cells and atrial derived HL-1 cells....

  5. Assessment of transient stability of cable based transmission grids with reactive power compensation

    DEFF Research Database (Denmark)

    Foo, Yii; Dall, Laurids; Silva, Filipe Miguel Faria da

    2017-01-01

    Underground transmission cables are gaining popularity due to its applications near cities and aesthetic purpose. For example in Denmark, the transmission power grid is changing significantly as many conventional overhead lines (OHL) are replaced by cables and more is expected over the coming years...... through a series of sensitivity analysis with respect to the cables compensation degree. A separate case of disconnecting the SRs of the faulted line is also carried out. The tendencies are initially observed and explained for smaller systems, Single-Machine Infinite Bus (SMIB) and 9-bus system...

  6. A fuzzy-logic antiswing controller for three-dimensional overhead cranes.

    Science.gov (United States)

    Cho, Sung-Kun; Lee, Ho-Hoon

    2002-04-01

    In this paper, a new fuzzy antiswing control scheme is proposed for a three-dimensional overhead crane. The proposed control consists of a position servo control and a fuzzy-logic control. The position servo control is used to control crane position and rope length, and the fuzzy-logic control is used to suppress load swing. The proposed control guarantees not only prompt suppression of load swing but also accurate control of crane position and rope length for simultaneous travel, traverse, and hoisting motions of the crane. Furthermore, the proposed control provides practical gain tuning criteria for easy application. The effectiveness of the proposed control is shown by experiments with a three-dimensional prototype overhead crane.

  7. ZoOHPraxiscope, Re-Inventing the Zoopraxiscope with an Overhead Projector

    Directory of Open Access Journals (Sweden)

    Christian Faubel

    2015-11-01

    Full Text Available The ZoOHPraxiscope is a modified overhead projector that can be used to show cinematographic animations. It allows blending and mixing of animated shadow play with cinematographic animation. Similar to the Zoopraxiscope that was developed by the photographer Eadweard Muybridge in the 19th century, the ZoOHPraxiscope combines a rotating picture disc with a Laterna Magica and shutter mechanism. The mechanical shutter of the original device is replaced by a high-power LED that can be turned on and off at the fraction of a second. The overhead projector acts as Laterna Magica. This new device is used as a performance instrument to combine sound, vision, shadow play and animation.

  8. Channel-aware multi-user uplink transmission scheme for SIMO-OFDM systems

    Institute of Scientific and Technical Information of China (English)

    PAN ChengKang; CAI YueMing; XU YouYun

    2009-01-01

    The problem of medium access control (MAC) in wireless single-Input multiple-output-orthogonal frequency division multiplexing (SIMO-OFOM) systems is addressed.Traditional random access protocols have low overheads and inferior performance.Centralized methods have superior performance and high overheads.To achieve the tradeoff between overhead and performance,we propose a channelaware uplink transmission (CaUT) scheme for SIMO-OFDM systems.In CaUT,users transmit requestto-send (RTS) at some subcarriers whose channel gains are above a predetermined threshold.Using the channel state information provided by RTS,access point performs user selection with receive beamforming to decide which users can access and then broadcasts the selection results via clear-to-send (CTS) to users.We present a distributed power control scheme by using a simple fixed modulation mode.We optimize the modulation order and channel gain thresholds to maximize the separable packets subject to the bit-error-rate (BER) and temporal fairness requirements and the Individual average transmit power constraints.The performance of CaUT scheme is analyzed analytically and evaluated by simulations.Simulation results show that CaUT can achieve more significant throughput performance than traditional random access protocols.

  9. Problems due to icing of overhead lines - Part II

    International Nuclear Information System (INIS)

    Havard, D.G.; Pon, C.J.; Krishnasamy, S.G.

    1985-01-01

    A companion paper describes uncertainties in overhead line design due to the variability of ice and wind loads. This paper reviews two other effects due to icing; conductor galloping and torsional instability, which require further study. (author)

  10. SU-E-I-23: A General KV Constrained Optimization of CNR for CT Abdominal Imaging

    International Nuclear Information System (INIS)

    Weir, V; Zhang, J

    2015-01-01

    Purpose: While Tube current modulation has been well accepted for CT dose reduction, kV adjusting in clinical settings is still at its early stage. This is mainly due to the limited kV options of most current CT scanners. kV adjusting can potentially reduce radiation dose and optimize image quality. This study is to optimize CT abdomen imaging acquisition based on the assumption of a continuous kV, with the goal to provide the best contrast to noise ratio (CNR). Methods: For a given dose (CTDIvol) level, the CNRs at different kV and pitches were measured with an ACR GAMMEX phantom. The phantom was scanned in a Siemens Sensation 64 scanner and a GE VCT 64 scanner. A constrained mathematical optimization was used to find the kV which led to the highest CNR for the anatomy and pitch setting. Parametric equations were obtained from polynomial fitting of plots of kVs vs CNRs. A suitable constraint region for optimization was chosen. Subsequent optimization yielded a peak CNR at a particular kV for different collimations and pitch setting. Results: The constrained mathematical optimization approach yields kV of 114.83 and 113.46, with CNRs of 1.27 and 1.11 at the pitch of 1.2 and 1.4, respectively, for the Siemens Sensation 64 scanner with the collimation of 32 x 0.625mm. An optimized kV of 134.25 and 1.51 CNR is obtained for a GE VCT 64 slice scanner with a collimation of 32 x 0.625mm and a pitch of 0.969. At 0.516 pitch and 32 x 0.625 mm an optimized kV of 133.75 and a CNR of 1.14 was found for the GE VCT 64 slice scanner. Conclusion: CNR in CT image acquisition can be further optimized with a continuous kV option instead of current discrete or fixed kV settings. A continuous kV option is a key for individualized CT protocols

  11. SU-E-I-23: A General KV Constrained Optimization of CNR for CT Abdominal Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Weir, V; Zhang, J [University of Kentucky, Lexington, KY (United States)

    2015-06-15

    Purpose: While Tube current modulation has been well accepted for CT dose reduction, kV adjusting in clinical settings is still at its early stage. This is mainly due to the limited kV options of most current CT scanners. kV adjusting can potentially reduce radiation dose and optimize image quality. This study is to optimize CT abdomen imaging acquisition based on the assumption of a continuous kV, with the goal to provide the best contrast to noise ratio (CNR). Methods: For a given dose (CTDIvol) level, the CNRs at different kV and pitches were measured with an ACR GAMMEX phantom. The phantom was scanned in a Siemens Sensation 64 scanner and a GE VCT 64 scanner. A constrained mathematical optimization was used to find the kV which led to the highest CNR for the anatomy and pitch setting. Parametric equations were obtained from polynomial fitting of plots of kVs vs CNRs. A suitable constraint region for optimization was chosen. Subsequent optimization yielded a peak CNR at a particular kV for different collimations and pitch setting. Results: The constrained mathematical optimization approach yields kV of 114.83 and 113.46, with CNRs of 1.27 and 1.11 at the pitch of 1.2 and 1.4, respectively, for the Siemens Sensation 64 scanner with the collimation of 32 x 0.625mm. An optimized kV of 134.25 and 1.51 CNR is obtained for a GE VCT 64 slice scanner with a collimation of 32 x 0.625mm and a pitch of 0.969. At 0.516 pitch and 32 x 0.625 mm an optimized kV of 133.75 and a CNR of 1.14 was found for the GE VCT 64 slice scanner. Conclusion: CNR in CT image acquisition can be further optimized with a continuous kV option instead of current discrete or fixed kV settings. A continuous kV option is a key for individualized CT protocols.

  12. Recovery and updating of power transmission lines. The experience made by ELETROSUL; Recapacitacao e repotenciacao de linhas de transmissao. A experiencia da ELETROSUL

    Energy Technology Data Exchange (ETDEWEB)

    Stephan, Jose Carlos de Saboia [ELETROSUL, Curitiba, PR (Brazil)]. E-mail: jcsaboia@eletrosul.gov.br

    2001-07-01

    This document presents a procedures synthesis for analysis and verification of power transmission line adjustments, aiming their recovery or power updating, it also shows the executed procedures during the stages of preliminary design, final design and construction of the modernized transmission lines by ELETROSUL for the 138, 230 and 500 Kv tensions. The concepts on which the evaluation criteria of the structural components for the transmission lines(metallic supports, foundations in metallic grills and reinforced concrete) have been based are presented, as well as the main aspects of the used methodologies for that. It also makes a comparative analysis related to the used processes for structural analyses of the metallic support in trelliswork (computational process which uses the finite element and graphical methods), as well as the foundations of these supports (structural verifications and others). Also are reported the researches and jobs which involved the power updating of the three 138 and 230 kv transmission lines of ELETROSUL.

  13. Testing of the 3M Company ACCR Conductor

    Energy Technology Data Exchange (ETDEWEB)

    Stovall, J.P.; RIzy, D.T.; Kisner, R.A.; Deve, H.E. (3M Comp.)

    2010-09-15

    The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum- Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors so the core has a lower density and higher conductivity. The objective of this work is to accelerate the commercial acceptance by electric utilities of these new conductor designs by testing four representative conductor classes in controlled conditions. Overhead transmission lines use bare aluminum conductor strands wrapped around a steel core strands to transmit electricity. The typical cable is referred to as aluminum-conductor steel-reinforced (ACSR). The outer strands are aluminum, chosen for its conductivity, low weight, and low cost. The center strand is of steel for the strength required to support the weight without stretching the aluminum due to its ductility. The power density of a transmission corridor has been directly increased by increasing the voltage level. Transmission voltages have increased from 115-kV to 765- kV over the past 80 years. In the United States, further increasing the voltage level is not feasible at this point in time, so in order to further increase the power density of a transmission corridor, conductor designs that increase the current carrying capability have been examined. One of the key limiting factors in the design of a transmission line is the conductor sag which determines the clearance of the conductor above ground or underlying structures needed for electrical safety. Increasing the current carrying capability of a conductor increases the joule heating in the conductor which increases the conductor sag. A conductor designed for high-temperature and lowsag operation requires an engineered modification of the conductor materials. To make an advanced cable, the 3M Company solution has been the development of a composite conductor consisting of Nextel ceramic fibers to replace the steel core and

  14. Removal of the Materials Test Reactor overhead working reservoir

    International Nuclear Information System (INIS)

    Lunis, B.C.

    1975-10-01

    Salient features of the removal of an excessed contaminated facility, the Materials Test Reactor (MTR) overhead working reservoir (OWR) from the Test Reactor Area to the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory are described. The 125-ton OWR was an overhead 160,000-gallon-capacity tank approximately 193 feet high which supplied cooling water to the MTR. Radiation at ground level beneath the tank was 5 mR/hr and approximately 600 mR/hr at the exterior surface of the tank. Sources ranging from 3 R/hr to in excess of 500 R/hr exist within the tank. The tank interior is contaminated with uranium, plutonium, and miscellaneous fission products. The OWR was lowered to ground level with the use of explosive cutters. Dismantling, decontamination, and disposal were performed by Aerojet Nuclear Company maintenance forces

  15. LEVELS OF EXTREMELY LOW-FREQUENCY ELECTRIC AND MAGNETIC FIELDS FROM OVERHEAD POWER LINES IN THE OUTDOOR ENVIRONMENT OF RAMALLAH CITY-PALESTINE.

    Science.gov (United States)

    Abuasbi, Falastine; Lahham, Adnan; Abdel-Raziq, Issam Rashid

    2018-05-01

    In this study, levels of extremely low-frequency electric and magnetic fields originated from overhead power lines were investigated in the outdoor environment in Ramallah city, Palestine. Spot measurements were applied to record fields intensities over 6-min period. The Spectrum Analyzer NF-5035 was used to perform measurements at 1 m above ground level and directly underneath 40 randomly selected power lines distributed fairly within the city. Levels of electric fields varied depending on the line's category (power line, transformer or distributor), a minimum mean electric field of 3.9 V/m was found under a distributor line, and a maximum of 769.4 V/m under a high-voltage power line (66 kV). However, results of electric fields showed a log-normal distribution with the geometric mean and the geometric standard deviation of 35.9 and 2.8 V/m, respectively. Magnetic fields measured at power lines, on contrast, were not log-normally distributed; the minimum and maximum mean magnetic fields under power lines were 0.89 and 3.5 μT, respectively. As a result, none of the measured fields exceeded the ICNIRP's guidelines recommended for general public exposures to extremely low-frequency fields.

  16. Development of Highly Selective Kv1.3-Blocking Peptides Based on the Sea Anemone Peptide ShK

    Directory of Open Access Journals (Sweden)

    Michael W. Pennington

    2015-01-01

    Full Text Available ShK, from the sea anemone Stichodactyla helianthus, is a 35-residue disulfide-rich peptide that blocks the voltage-gated potassium channel Kv1.3 at ca. 10 pM and the related channel Kv1.1 at ca. 16 pM. We developed an analog of this peptide, ShK-186, which is currently in Phase 1b-2a clinical trials for the treatment of autoimmune diseases such as multiple sclerosis and rheumatoid arthritis. While ShK-186 displays a >100-fold improvement in selectivity for Kv1.3 over Kv1.1 compared with ShK, there is considerable interest in developing peptides with an even greater selectivity ratio. In this report, we describe several variants of ShK that incorporate p-phophono-phenylalanine at the N-terminus coupled with internal substitutions at Gln16 and Met21. In addition, we also explored the combinatorial effects of these internal substitutions with an alanine extension at the C-terminus. Their selectivity was determined by patch-clamp electrophysiology on Kv1.3 and Kv1.1 channels stably expressed in mouse fibroblasts. The peptides with an alanine extension blocked Kv1.3 at low pM concentrations and exhibited up to 2250-fold selectivity for Kv1.3 over Kv1.1. Analogs that incorporates p-phosphono-phenylalanine at the N-terminus blocked Kv1.3 with IC50s in the low pM range and did not affect Kv1.1 at concentrations up to 100 nM, displaying a selectivity enhancement of >10,000-fold for Kv1.3 over Kv1.1. Other potentially important Kv channels such as Kv1.4 and Kv1.6 were only partially blocked at 100 nM concentrations of each of the ShK analogs.

  17. Quality control of a kV cone beam computed tomography imaging system

    International Nuclear Information System (INIS)

    Marguet, M.; Bodez, V.

    2009-01-01

    Purpose: This work presents the introduction of a quality assurance program for the On-Board Imager (O.B.I., Varian) kV cone beam computed tomography (kV C.B.C.T.) system, together with the results of 1 year monthly testing. Materials and methods: Firstly the geometric precision and stability of the equipment and of the associated software were evaluated using the Marker phantom. The coincidence of the accelerator isocenter and the imager isocenter was verified as well as the accuracy of the registration of kV cone beam computed tomography (kV C.B.C.T.) with reference CT images. Then, the kV C.B.C.T. image quality was evaluated using the Catphan 504 phantom and ArtiScan software (Aquilab) for both full-fan (F.F.) and half-fan (H.F.) imaging modes. Results: The kV C.B.C.T. isocenter and image registration with correction of the table position were found to be within a tolerance of 2.0 mm. Concerning the kV C.B.C.T. image quality, image noise and uniformity, the Hounsfield units (HU) stability and linearity, geometric distortion and high contrast resolution were all found to be within the manufacturer's recommendations for both F.F. and H.F. modes. However, the low contrast resolution for the HF mode did not meet the manufacturer's specifications. Conclusion: The quality assurance tests introduced have defined the initial system characteristics and their evolution during a period of 1 year, demonstrating the stability of the O.B.I.. (authors)

  18. Operational overhead of moving to higher energies

    CERN Document Server

    Lamont, M

    2011-01-01

    The operational overheads of moving above 3.5 TeV are examined. The costs of performing such a move at the start, or during, the 2011 run are evaluated. The impact of operation with beams above 3.5 TeV on machine protection systems is briefly reviewed, and any potential limitations are enumerated. Finally the possible benefits of increasing the beam energy on the luminosity are discussed.

  19. A comparison of kV and MV imaging in head and neck image guided radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Devereux, B. [Radiation Oncology Queensland, 280 North St, Toowoomba 4350 (Australia)], E-mail: beth.devereux@roq.net.au; Frantzis, J.; Sisson, T.; Jones, M.; Martin, J.; Middleton, M. [Radiation Oncology Queensland, 280 North St, Toowoomba 4350 (Australia)

    2010-02-15

    Purpose: To compare and assess kV and MV imaging modalities and their role in image guided radiotherapy (IGRT) for head and neck cancer patients. Method: Twelve patients receiving radical radiotherapy to the head and neck were analysed in this study. Six patients undertook MV daily online intervention and a further six patients undertook kV daily online intervention. Pre-intervention field placement data were collected from three separate observers' image match analysis for each patient. The radiotherapy collective involved in the daily online image match analysis formed the fourth observer in the study. The primary end point was to establish the difference in inter- and intra-observer variance between kV and MV imaging modalities. Results: The range of the standard deviations of systematic set-up error for MV imaging calculated was 1.47-2.33 mm (MV) and 1.61-1.64 mm (kV) for the right-left (RL), 2.10-2.17 mm (MV) and 1.53-1.84 mm (kV) for the cranio-caudal (CC) and 1.43-1.63 mm (MV) and 1.02-1.11 mm (kV) for the anterior-posterior (AP). The mean inter-observer variance was 0.21 mm (MV) and 0.41 mm (kV) for the RL, 0.53 mm (MV) and 0.55 mm (kV) for the CC and 0.23 mm (MV) and 0.16 mm (kV) for the AP direction. Intra-observer mean variance was in the order of 0.60 mm (MV) and 0.16 mm (kV) for the RL, 1.41 mm (MV) and 0.05 mm (kV) for the CC and 1.41 mm (MV) and 0.08 mm (kV) for the AP. Discussion: The data in this study suggest both inter- and intra-observer consistency across kV and MV imaging modalities were comparable. However, it is felt that the improved clarity and quality of kV imaging allows all observers to analyse images in a consistent manner, identifying and acting on potential field placement moves. Conclusion: The introduction of kV imaging has maintained the high levels of inter- and intra-observer consistency achieved with MV imaging. This in turn further enables positive verification outcomes and supports the implementation of potential

  20. Do overhead sports increase risk for rotator cuff tears in wheelchair users?

    Science.gov (United States)

    Akbar, Michael; Brunner, Manuela; Ewerbeck, Volker; Wiedenhöfer, Bernd; Grieser, Thomas; Bruckner, Thomas; Loew, Markus; Raiss, Patric

    2015-03-01

    To analyze whether frequent overhead-sports activity increases the risk for rotator cuff disease in patients with spinal cord injuries (SCIs) who are wheelchair dependent. Cross-sectional study, risk analysis. Department of Orthopaedic Surgery, Trauma Surgery and Spinal Cord Injury. Patients (N=296) with SCI requiring the full-time use of a manual wheelchair were recruited for this study. The total population was divided into 2 groups (sports vs no sports), among them 103 patients playing overhead sports on a regular basis (at least 1-2 times/wk) and 193 patients involved in overhead sports less than once a week or in no sports activity at all. The mean age of the sports group was 49.1 years. The mean duration of wheelchair dependence was 26.5 years. The mean age of the no-sports group was 48 years. The mean duration of wheelchair dependence was 25.2 years. Each individual completed a questionnaire designed to identify overhead-sports activity on a regular basis and was asked about shoulder problems. Magnetic resonance imaging scans of both shoulders were performed in each patient and analyzed in a standardized fashion. None. Possible differences in continuous data between patients with and without rotator cuff tear were evaluated. The relative risk of suffering from a rotator cuff tear between patients playing overhead sports and those not playing overhead sports was calculated. One hundred three patients played overhead sports regularly and 193 did not. There was no difference between groups regarding age, sex, level of SCI, and duration of wheelchair dependence. The body mass index was significantly lower in the sports group than in the no-sports group (Psports group and in 36.3% of the patients in the no-sports group (Psports group to develop rotator cuff tears was twice as high as for the no-sports group (95% confidence interval, 1.7-2.6; Psports activities have been identified as an additional risk factor, along with age and duration of wheelchair dependence

  1. Performance Analysis of a Voltage Source Converter (VSC based HVDC Transmission System under Faulted Conditions

    Directory of Open Access Journals (Sweden)

    Amiri RABIE

    2009-12-01

    Full Text Available Voltage Source Converter (VSC based HVDC transmission technology hasbeen selected as the basis for several recent projects due to its controllability,compact modular design, ease of system interface, and low environmentalimpact. This paper investigates the dynamic performance of a 200MW,±100kV VSC-HVDC transmission system under some faulted conditionsusing MATLAB/Simulink. Simulation results confirm the satisfactoryperformance of the proposed system under active and reactive powervariations and fault conditions.

  2. Fundamental role for the KCNE4 ancillary subunit in Kv7.4 regulation of arterial tone

    DEFF Research Database (Denmark)

    Jepps, Thomas A; Carr, Georgina; Lundegaard, Pia R

    2015-01-01

    tone by Kv7 channels. In HEK cells expressing Kv7.4, co-expression of KCNE4 increased the membrane expression of Kv7.4 and significantly altered Kv7.4 current properties. Quantitative PCR analysis of different rat arteries found that the KCNE4 isoform predominated and proximity ligation experiments...... leads to reduced Kv7.4 membrane abundance, a depolarized membrane potential and an augmented response to vasoconstrictors. KCNE4 is a key regulator of the function and expression of Kv7.4 in vascular smooth muscle. ABSTRACT: The KCNE ancillary subunits (KCNE1-5) significantly alter the expression...... to reduced Kv7.4 membrane abundance, a depolarized membrane potential and an augmented response to vasoconstrictors. The present study is the first to demonstrate an integral role of KCNE4 in regulating the function and expression of Kv7.4 in vascular smooth muscle....

  3. Hinkley Point 'C' power station public inquiry: outline statement of case

    International Nuclear Information System (INIS)

    1988-05-01

    This outline statement relates to the public inquiry to be held into the planning application by the Central Electricity Generating Board (CEGB) to construct a 1200 MW Pressurized Water Reactor (PWR) power station at Hinkley Point (Hinkley Point ''C'') in the United Kingdom, adjacent to an existing nuclear power station. The inquiry will consider economic, safety, environmental and planning matters relevant to the application and the implications for agriculture and local amenities of the re-aligning of two 400 kV overhead transmission lines. The outline statement contains submissions on: policy contest and approach; the requirement for Hinkley Point ''C''; design and safety; local issues. (UK)

  4. Electric power transmission for a Hanford Nuclear Energy Center (HNEC)

    International Nuclear Information System (INIS)

    Harty, H.; Dowis, W.J.

    1983-06-01

    The original study of transmission for a Hanford Nuclear Energy Center (HNEC), which was completed in September 1975, was updated in June 1978. The present 1983 revision takes cognizance of recent changes in the electric power situation of the PNW with respect to: (1) forecasts of load growth, (2) the feasibility of early use of 1100 kV transmission, and (3) the narrowing opportunities for siting nuclear plants in the region. The purpose of this update is to explore and describe additions to the existing transmission system that would be necessary to accommodate three levels of generation at HNEC. Comparisons with a PNW system having new thermal generating capacity distributed throughout the marketing region are not made as was done in earlier versions

  5. An Issue of Boundary Value for Velocity and Training Overhead Using Cooperative MIMO Technique in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    M. R. Islam

    2011-06-01

    Full Text Available A boundary value of velocity of data gathering node (DGN and a critical value for training overhead beyond which the cooperative communication in wireless sensor network will not be feasible is proposed in this paper. Multiple Input Multiple Outputs (MIMO cooperative communication is taken as an application. The performance in terms of energy efficiency and delay for a combination of two transmitting and two receiving antennas is analyzed. The results show that a set of critical value of velocity and training overhead pair is present for the long haul communication from the sensors to the data gathering node. Later a graphical relation between boundary value of training overhead and velocity is simulated. A mathematical relation between velocity and training overhead is also developed. The effects of several parameters on training overhead and velocity are analyzed.

  6. Downregulation of Kv7.4 channel activity in primary and secondary hypertension

    DEFF Research Database (Denmark)

    Jepps, Thomas Andrew; Chadha, Preet S; Davis, Alison J

    2011-01-01

    Voltage-gated potassium (K(+)) channels encoded by KCNQ genes (Kv7 channels) have been identified in various rodent and human blood vessels as key regulators of vascular tone; however, nothing is known about the functional impact of these channels in vascular disease. We ascertained the effect of...... structurally different activators of Kv7.2 through Kv7.5 channels (BMS-204352, S-1, and retigabine) on blood vessels from normotensive and hypertensive animals.......Voltage-gated potassium (K(+)) channels encoded by KCNQ genes (Kv7 channels) have been identified in various rodent and human blood vessels as key regulators of vascular tone; however, nothing is known about the functional impact of these channels in vascular disease. We ascertained the effect of 3...

  7. Optimization of the box-girder of overhead crane with constrained ...

    African Journals Online (AJOL)

    haroun

    Keywords: Overhead crane - Box-girder - New bat algorithm - level of ... much more efficiency and robustness compared to the genetic algorithm (GA) and PSO ...... optimization: developments, applications and resources," in Evolutionary.

  8. Immunomodulatory effects of diclofenac in leukocytes through the targeting of Kv1.3 voltage-dependent potassium channels.

    Science.gov (United States)

    Villalonga, Núria; David, Miren; Bielańska, Joanna; González, Teresa; Parra, David; Soler, Concepció; Comes, Núria; Valenzuela, Carmen; Felipe, Antonio

    2010-09-15

    Kv1.3 plays a crucial role in the activation and proliferation of T-lymphocytes and macrophages. While Kv1.3 is responsible for the voltage-dependent potassium current in T-cells, in macrophages this K(+) current is generated by the association of Kv1.3 and Kv1.5. Patients with autoimmune diseases show a high number of effector memory T cells that are characterized by a high expression of Kv1.3 and Kv1.3 antagonists ameliorate autoimmune disorders in vivo. Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) used in patients who suffer from painful autoimmune diseases such as rheumatoid arthritis. In this study, we show that diclofenac impairs immune response via a mechanism that involves Kv1.3. While diclofenac inhibited Kv1.3 expression in activated macrophages and T-lymphocytes, Kv1.5 remained unaffected. Diclofenac also decreased iNOS levels in Raw 264.7 cells, impairing their activation in response to lipopolysaccharide (LPS). LPS-induced macrophage migration and IL-2 production in stimulated Jurkat T-cells were also blocked by pharmacological doses of diclofenac. These effects were mimicked by Margatoxin, a specific Kv1.3 inhibitor, and Charybdotoxin, which blocks both Kv1.3 and Ca(2+)-activated K(+) channels (K(Ca)3.1). Because Kv1.3 is a very good target for autoimmune therapies, the effects of diclofenac on Kv1.3 are of high pharmacological relevance. Copyright 2010 Elsevier Inc. All rights reserved.

  9. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-146-Custer-Ingledow No. 1 & 2)

    Energy Technology Data Exchange (ETDEWEB)

    Shurtliff, Aaron [Bonneville Power Administration, Portland, OR (United States)

    2003-04-29

    Vegetation Management for portion of the Custer-Ingledow No.1&2 500 kV transmission line located from tower structure 1/4 to 9/6. BPA proposes to clear unwanted vegetation in the rights-of-ways and around tower structures that may impede the operation and maintenance of the subject transmission line. Also, access road clearing will be conducted.

  10. 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.

  11. Silencing of Kv4.1 potassium channels inhibits cell proliferation of tumorigenic human mammary epithelial cells

    International Nuclear Information System (INIS)

    Jang, Soo Hwa; Choi, Changsun; Hong, Seong-Geun; Yarishkin, Oleg V.; Bae, Young Min; Kim, Jae Gon; O'Grady, Scott M.; Yoon, Kyong-Ah; Kang, Kyung-Sun; Ryu, Pan Dong; Lee, So Yeong

    2009-01-01

    Potassium channel activity has been shown to facilitate cell proliferation in cancer cells. In the present study, the role of Kv4.1 channels in immortal and tumorigenic human mammary epithelial cells was investigated. Kv4.1 protein expression was positively correlated with tumorigenicity. Moreover, transfection with siRNAs targeting Kv4.1 mRNA suppressed proliferation of tumorigenic mammary epithelial cells. Experiments using mRNA isolated from human breast cancer tissues revealed that the level of Kv4.1 mRNA expression varied depending on the stage of the tumor. Kv4.1 protein expression increased during stages T2 and T3 compared to normal tissue. These results demonstrated that Kv4.1 plays a role in proliferation of tumorigenic human mammary epithelial cells. In addition, elevated Kv4.1 expression may be useful as a diagnostic marker for staging mammary tumors and selective blockers of Kv4.1 may serve to suppress tumor cell proliferation.

  12. Mode and climatic factors effect on energy losses in transient heat modes of transmission lines

    Science.gov (United States)

    Bigun, A. Ya; Sidorov, O. A.; Osipov, D. S.; Girshin, S. S.; Goryunov, V. N.; Petrova, E. V.

    2018-01-01

    Electrical energy losses increase in modern grids. The losses are connected with an increase in consumption. Existing models of electric power losses estimation considering climatic factors do not allow estimating the cable temperature in real time. Considering weather and mode factors in real time allows to meet effectively and safely the consumer’s needs to minimize energy losses during transmission, to use electric power equipment effectively. These factors increase an interest in the evaluation of the dynamic thermal mode of overhead transmission lines conductors. The article discusses an approximate analytic solution of the heat balance equation in the transient operation mode of overhead lines based on the least squares method. The accuracy of the results obtained is comparable with the results of solving the heat balance equation of transient thermal mode with the Runge-Kutt method. The analysis of mode and climatic factors effect on the cable temperature in a dynamic thermal mode is presented. The calculation of the maximum permissible current for variation of weather conditions is made. The average electric energy losses during the transient process are calculated with the change of wind, air temperature and solar radiation. The parameters having the greatest effect on the transmission capacity are identified.

  13. A truncated Kv1.1 protein in the brain of the megencephaly mouse: expression and interaction

    Directory of Open Access Journals (Sweden)

    Århem Peter

    2005-11-01

    Full Text Available Abstract Background The megencephaly mouse, mceph/mceph, is epileptic and displays a dramatically increased brain volume and neuronal count. The responsible mutation was recently revealed to be an eleven base pair deletion, leading to a frame shift, in the gene encoding the potassium channel Kv1.1. The predicted MCEPH protein is truncated at amino acid 230 out of 495. Truncated proteins are usually not expressed since nonsense mRNAs are most often degraded. However, high Kv1.1 mRNA levels in mceph/mceph brain indicated that it escaped this control mechanism. Therefore, we hypothesized that the truncated Kv1.1 would be expressed and dysregulate other Kv1 subunits in the mceph/mceph mice. Results We found that the MCEPH protein is expressed in the brain of mceph/mceph mice. MCEPH was found to lack mature (Golgi glycosylation, but to be core glycosylated and trapped in the endoplasmic reticulum (ER. Interactions between MCEPH and other Kv1 subunits were studied in cell culture, Xenopus oocytes and the brain. MCEPH can form tetramers with Kv1.1 in cell culture and has a dominant negative effect on Kv1.2 and Kv1.3 currents in oocytes. However, it does not retain Kv1.2 in the ER of neurons. Conclusion The megencephaly mice express a truncated Kv1.1 in the brain, and constitute a unique tool to study Kv1.1 trafficking relevant for understanding epilepsy, ataxia and pathologic brain overgrowth.

  14. Vegetation clearance distances to prevent wildland fire caused damage to telecommunication and power transmission infrastructure (2)

    Science.gov (United States)

    B. W. Butler; T. Wallace; J. Hogge

    2015-01-01

    Towers and poles supporting power transmission and telecommunication lines have collapsed due to heating from wildland fires. Such occurrences have led to interruptions in power or communication in large municipal areas with associated social and political implications as well as increased immediate danger to humans. Vegetation clearance standards for overhead...

  15. Novel Kv7.1-phosphatidylinositol 4,5-bisphosphate interaction sites uncovered by charge neutralization scanning

    DEFF Research Database (Denmark)

    Eckey, Karina; Wrobel, Eva; Strutz-Seebohm, Nathalie

    2014-01-01

    Kv7.1 to Kv7.5 α-subunits belong to the family of voltage-gated potassium channels (Kv). Assembled with the β-subunit KCNE1, Kv7.1 conducts the slowly activating potassium current IKs, which is one of the major currents underlying repolarization of the cardiac action potential. A known regulator...... of corresponding long QT syndrome mutants suggested impaired PIP2 regulation as the cause for channel dysfunction. To clarify the underlying structural mechanism of PIP2 binding, molecular dynamics simulations of Kv7.1/KCNE1 complexes containing two PIP2 molecules in each subunit at specific sites were performed...

  16. Authentication and consensus overhead in vehicular ad hoc networks

    NARCIS (Netherlands)

    Petit, Jonathan; Mammeri, Zoubir

    Vehicular ad hoc networks aim at increasing passenger safety by exchanging warning messages between vehicles wirelessly. A main challenge is to resist to various malicious abuses and security attacks. However, any security mechanism comes with overhead. We analyze how the authentication algorithm

  17. Human Factors Engineering Guidelines for Overhead Cranes

    Science.gov (United States)

    Chandler, Faith; Delgado, H. (Technical Monitor)

    2001-01-01

    This guideline provides standards for overhead crane cabs that can be applied to the design and modification of crane cabs to reduce the potential for human error due to design. This guideline serves as an aid during the development of a specification for purchases of cranes or for an engineering support request for crane design modification. It aids human factors engineers in evaluating existing cranes during accident investigations or safety reviews.

  18. From pan-reactive KV7 channel opener to subtype selective opener/inhibitor by addition of a methyl group.

    Directory of Open Access Journals (Sweden)

    Sigrid Marie Blom

    Full Text Available The voltage-gated potassium channels of the KV7 family (KV7.1-5 play important roles in controlling neuronal excitability and are therefore attractive targets for treatment of CNS disorders linked to hyperexcitability. One of the main challenges in developing KV7 channel active drugs has been to identify compounds capable of discriminating between the neuronally expressed subtypes (KV7.2-5, aiding the identification of the subunit composition of KV7 currents in various tissues, and possessing better therapeutic potential for particular indications. By taking advantage of the structure-activity relationship of acrylamide KV7 channel openers and the effects of these compounds on mutant KV7 channels, we have designed and synthesized a novel KV7 channel modulator with a unique profile. The compound, named SMB-1, is an inhibitor of KV7.2 and an activator of KV7.4. SMB-1 inhibits KV7.2 by reducing the current amplitude and increasing the time constant for the slow component of the activation kinetics. The activation of KV7.4 is seen as an increase in the current amplitude and a slowing of the deactivation kinetics. Experiments studying mutant channels with a compromised binding site for the KV7.2-5 opener retigabine indicate that SMB-1 binds within the same pocket as retigabine for both inhibition of KV7.2 and activation of KV7.4. SMB-1 may serve as a valuable tool for KV7 channel research and may be used as a template for further design of better subtype selective KV7 channel modulators. A compound with this profile could hold novel therapeutic potential such as the treatment of both positive and cognitive symptoms in schizophrenia.

  19. Communication overhead on the Intel Paragon, IBM SP2 and Meiko CS-2

    Science.gov (United States)

    Bokhari, Shahid H.

    1995-01-01

    Interprocessor communication overhead is a crucial measure of the power of parallel computing systems-its impact can severely limit the performance of parallel programs. This report presents measurements of communication overhead on three contemporary commercial multicomputer systems: the Intel Paragon, the IBM SP2 and the Meiko CS-2. In each case the time to communicate between processors is presented as a function of message length. The time for global synchronization and memory access is discussed. The performance of these machines in emulating hypercubes and executing random pairwise exchanges is also investigated. It is shown that the interprocessor communication time depends heavily on the specific communication pattern required. These observations contradict the commonly held belief that communication overhead on contemporary machines is independent of the placement of tasks on processors. The information presented in this report permits the evaluation of the efficiency of parallel algorithm implementations against standard baselines.

  20. Beamforming transmission in IEEE 802.11ac under time-varying channels.

    Science.gov (United States)

    Yu, Heejung; Kim, Taejoon

    2014-01-01

    The IEEE 802.11ac wireless local area network (WLAN) standard has adopted beamforming (BF) schemes to improve spectral efficiency and throughput with multiple antennas. To design the transmit beam, a channel sounding process to feedback channel state information (CSI) is required. Due to sounding overhead, throughput increases with the amount of transmit data under static channels. Under practical channel conditions with mobility, however, the mismatch between the transmit beam and the channel at transmission time causes performance loss when transmission duration after channel sounding is too long. When the fading rate, payload size, and operating signal-to-noise ratio are given, the optimal transmission duration (i.e., packet length) can be determined to maximize throughput. The relationship between packet length and throughput is also investigated for single-user and multiuser BF modes.

  1. Evaluation of “direct input” effectiveness for industrial enterprises power supply

    Directory of Open Access Journals (Sweden)

    Malinina Tatyana

    2017-01-01

    Full Text Available The cost of energy has increased significantly for the industrial enterprises over the recent years, due to an increase in the electricity tariffs and the changes in the rules of the electricity market. Tariffs for electricity sold to consumers, differentiated according to various parameters, one of which is the voltage range. The higher the voltage range, the lower the tariffs, and thus, the consumer pays less for the supplied energy. Currently only for big consumers made energy supply “direct input” through the construction of an overhead line (OL with a nominal voltage of 110 kV or 220 kV. However, it is advisable to consider the issue of power supply efficiency of big and medium-sized industrial enterprises based on the “direct input”. The questions of voltage level study based on empirical formulas are considered in the article, expressing the dependence of the voltage from the transmission distance and the amount of transmitted power. It was proven that these formulas give a large spread, so intermediate voltage classes 35 kV and 110 kV, which compared with the traditional option of power supply on the basis of the cable line 10 kV, have been selected. Based on the technical and economic calculations it has been proved the value of the transmit power and length of the line at which the power supply of industrial enterprise on the basis of “ direct input” with a nominal voltage of 110 kV becomes effective.

  2. Composite Extension Finite Fields for Low Overhead Network Coding

    DEFF Research Database (Denmark)

    Heide, Janus; Roetter, Daniel Enrique Lucani

    2015-01-01

    Although Network Coding (NC) has been proven to increase throughput and reliability in communication networks, its adoption is typically hindered by the additional complexity it introduces at various nodes in the network and the overhead to signal the coding coefficients associated with each code...

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

    Directory of Open Access Journals (Sweden)

    Liantao Wu

    2015-08-01

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

  4. New transmission interconnection reduces consumer costs

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2008-09-15

    The Central American electric interconnection system (SIEPAC) project will involve the construction of a 1830 km 230 kV transmission system that will link Guatemala, El Salvador, Honduras, Costa Rica, Nicaragua, and Panama. The system is expected to alleviate the region's power shortages and reduce electricity costs for consumers. Costs for the SIEPAC project have been estimated at $370 million. The system will serve approximately 37 million customers, and will include 15 substations. The contract for building the electrical equipment has been awarded to Schweitzer Engineering Laboratories (SEL) who plan to manufacture components at a plant in Mexico. The equipment will include high speed line protection, automation, and control systems. Line current differential systems and satellite-synchronized clocks will also be used. The new transmission system is expected to be fully operational by 2009. 1 fig.

  5. T Cell Subset and Stimulation Strength-Dependent Modulation of T Cell Activation by Kv1.3 Blockers.

    Directory of Open Access Journals (Sweden)

    Wai-Ping Fung-Leung

    Full Text Available Kv1.3 is a voltage-gated potassium channel expressed on T cells that plays an important role in T cell activation. Previous studies have shown that blocking Kv1.3 channels in human T cells during activation results in reduced calcium entry, cytokine production, and proliferation. The aim of the present study was to further explore the effects of Kv1.3 blockers on the response of different human T cell subsets under various stimulation conditions. Our studies show that, unlike the immune suppressor cyclosporine A, the inhibitory effect of Kv1.3 blockers was partial and stimulation strength dependent, with reduced inhibitory efficacy on T cells under strengthened anti-CD3/CD28 stimulations. T cell responses to allergens including house dust mites and ragweed were partially reduced by Kv1.3 blockers. The effect of Kv1.3 inhibition was dependent on T cell subsets, with stronger effects on CCR7- effector memory compared to CCR7+ central memory CD4 T cells. Calcium entry studies also revealed a population of CD4 T cells resistant to Kv1.3 blockade. Activation of CD4 T cells was accompanied with an increase in Kv1.3 currents but Kv1.3 transcripts were found to be reduced, suggesting a posttranscriptional mechanism in the regulation of Kv1.3 activities. In summary, Kv1.3 blockers inhibit T cell activation in a manner that is highly dependent on the T cell identity and stimulation strength, These findings suggest that Kv1.3 blockers inhibit T cells in a unique, conditional manner, further refining our understanding of the therapeutic potential of Kv1.3 blockers.

  6. BPA/Lower Valley transmission project. Final environmental impact statement

    International Nuclear Information System (INIS)

    1998-06-01

    Bonneville Power Administration and Lower Valley Power and Light, Inc. propose to solve a voltage stability problem in the Jackson and Afton, Wyoming areas. Lower Valley buys electricity from BPA and then supplies it to the residences and businesses of the Jackson and Afton, Wyoming areas. BPA is considering five alternatives. For the Agency Proposed Action, BPA and Lower Valley would construct a new 115-kV line from BPA's Swan Valley Substation near Swan Valley in Bonneville County, Idaho about 58 km (36 miles) east to BPA's Teton Substation near Jackson in Teton County, Wyoming. The new line would be next to an existing 115-kV line. The Single-Circuit Line Alternative has all the components of the Agency Proposed Action except that the entire line would be supported by single-circuit wood pole H-frame structures. the Short Line Alternative has all the components of the Single-Circuit Line Alternative except it would only be half as long. BPA would also construct a new switching station near the existing right-of-way, west or north of Targhee Tap. Targhee Tap would then be removed. For the Static Var Compensation Alternative, BPA would install a Static Var Compensator (SVC) at Teton or Jackson Substation. An SVC is a group of electrical equipment placed at a substation to help control voltage on a transmission system. The No Action Alternative assumes that no new transmission line is built, and no other equipment is added to the transmission system

  7. Transmission investment problems in Europe: Going beyond standard solutions

    International Nuclear Information System (INIS)

    Buijs, Patrik; Bekaert, David; Cole, Stijn; Van Hertem, Dirk; Belmans, Ronnie

    2011-01-01

    The European transmission grid is facing an investment challenge. There is a strong call for more transmission capacity. At the same time, the investment climate is fierce and troubled by public opposition, a complex regulatory framework, etc. Many transmission capacity expansion projects are delayed or canceled. In this paper different technology options suitable for increasing transmission capacity are discussed. The aim is to provide policy-makers with information on technologies without going too much into technical details. The focus is on opportunities and limitations to implement various technological alternatives in practice, including technical solutions that go beyond constructing new connection lines. The criteria used in this technology assessment are based on the obstacles reported in the European Priority Interconnection Plan. This ensures a realistic approach based on problems encountered in real projects. Although AC overhead lines (OHL) will remain the standard solution for grid expansion, it is argued that different technology options can overcome many obstacles that OHL face. Additionally, it is illustrated that the higher investment costs for some solutions can be offset with an increased benefit, e.g. by accomplishing investments with smaller delays due to fewer obstacles encountered. - Research highlights: → Assessment of real problems encountered in transmission investments. → Comparison of transmission technologies. → Techno-economic evaluation of transmission technologies.

  8. KCNE4 is an inhibitory subunit to Kv1.1 and Kv1.3 potassium channels

    DEFF Research Database (Denmark)

    Grunnet, Morten; Rasmussen, Hannne B; Hay-Schmidt, Anders

    2003-01-01

    is detected in the heart and in five different parts of the brain. Having the broad distribution of Kv1 channels in mind, the demonstrated inhibitory property of KCNE4-subunits could locally and/or transiently have a dramatic influence on cellular excitability and on setting resting membrane potentials....

  9. 23 CFR 140.907 - Overhead and indirect construction costs.

    Science.gov (United States)

    2010-04-01

    ... accounting principles; (2) The costs included in the distribution are limited to costs actually incurred by...), part 31, Contract Cost Principles and Procedures, relating to contracts with commercial organizations... 23 Highways 1 2010-04-01 2010-04-01 false Overhead and indirect construction costs. 140.907...

  10. Further Research on an Anti-Swing Control System for Overhead Cranes

    Directory of Open Access Journals (Sweden)

    B. Spruogis

    2018-02-01

    Full Text Available A method of reducing load oscillations that occur when overhead crane reaches destination position is presented in the article. The use of control drive scheme of crane bridge and trolley that ensures a smooth phase trajectory transition of the load to the optimum trajectory in accordance with Pontryagin's maximum principle is proposed. Mentioned control system changes the magnitude or direction of the traction force at the moment when the load is located above the destination. It is found that the degree of change of the traction force depends on the hoisting rope deviation angle from vertical. This study was conducted in order to provide more accurate and fast handling of loads by overhead crane.

  11. Effects of the small molecule HERG activator NS1643 on Kv11.3 channels.

    Directory of Open Access Journals (Sweden)

    Arne Bilet

    Full Text Available NS1643 is one of the small molecule HERG (Kv11.1 channel activators and has also been found to increase erg2 (Kv11.2 currents. We now investigated whether NS1643 is also able to act as an activator of Kv11.3 (erg3 channels expressed in CHO cells. Activation of rat Kv11.3 current occurred in a dose-dependent manner and maximal current increasing effects were obtained with 10 µM NS1643. At this concentration, steady-state outward current increased by about 80% and the current increase was associated with a significant shift in the voltage dependence of activation to more negative potentials by about 15 mV. In addition, activation kinetics were accelerated, whereas deactivation was slowed. There was no significant effect on the kinetics of inactivation and recovery from inactivation. The strong current-activating agonistic effect of NS1643 did not result from a shift in the voltage dependence of Kv11.3 channel inactivation and was independent from external Na(+ or Ca(2+. At the higher concentration of 20 µM, NS1643 induced clearly less current increase. The left shift in the voltage dependence of activation reversed and the voltage sensitivity of activation dramatically decreased along with a slowing of Kv11.3 channel activation. These data show that, in comparison to other Kv11 family members, NS1643 exerts distinct effects on Kv11.3 channels with especially pronounced partial antagonistic effects at higher concentration.

  12. Compilation time analysis to minimize run-time overhead in preemptive scheduling on multiprocessors

    Science.gov (United States)

    Wauters, Piet; Lauwereins, Rudy; Peperstraete, J.

    1994-10-01

    This paper describes a scheduling method for hard real-time Digital Signal Processing (DSP) applications, implemented on a multi-processor. Due to the very high operating frequencies of DSP applications (typically hundreds of kHz) runtime overhead should be kept as small as possible. Because static scheduling introduces very little run-time overhead it is used as much as possible. Dynamic pre-emption of tasks is allowed if and only if it leads to better performance in spite of the extra run-time overhead. We essentially combine static scheduling with dynamic pre-emption using static priorities. Since we are dealing with hard real-time applications we must be able to guarantee at compile-time that all timing requirements will be satisfied at run-time. We will show that our method performs at least as good as any static scheduling method. It also reduces the total amount of dynamic pre-emptions compared with run time methods like deadline monotonic scheduling.

  13. Kv4 channels underlie the subthreshold-operating A-type K+-current in nociceptive dorsal root ganglion neurons

    Directory of Open Access Journals (Sweden)

    Thanawath R Na Phuket

    2009-07-01

    Full Text Available The dorsal root ganglion (DRG contains heterogeneous populations of sensory neurons including primary nociceptive neurons and C-fibers implicated in pain signaling.  Recent studies have demonstrated DRG hyperexcitability associated with downregulation of A-type K+ channels; however, the molecular correlate of the corresponding A-type K+ current (IA has remained hypothetical.  Kv4 channels may underlie the IA in DRG neurons.  We combined electrophysiology, molecular biology (whole-tissue and single-cell RT-PCR and immunohistochemistry to investigate the molecular basis of the IA in acutely dissociated DRG neurons from 7-8 day-old rats.  Whole-cell recordings demonstrate a robust tetraethylammonium-resistant (20 mM and 4-aminopyridine-sensitive (5 mM IA.  Matching Kv4 channel properties, activation and inactivation of this IA occur in the subthreshold range of membrane potentials and the rate of recovery from inactivation is rapid and voltage-dependent.  Among Kv4 transcripts, the DRG expresses significant levels of Kv4.1 and Kv4.3 mRNAs.  Also, single small-medium diameter DRG neurons (~30 mm exhibit correlated frequent expression of mRNAs encoding Kv4.1 and Nav1.8, a known nociceptor marker.  In contrast, the expressions of Kv1.4 and Kv4.2 mRNAs at the whole-tissue and single-cell levels are relatively low and infrequent.  Kv4 protein expression in nociceptive DRG neurons was confirmed by immunohistochemistry, which demonstrates colocalization of Kv4.3 and Nav1.8, and negligible expression of Kv4.2.  Furthermore, specific dominant-negative suppression and overexpression strategies confirmed the contribution of Kv4 channels to IA in DRG neurons.  Contrasting the expression patterns of Kv4 channels in the central and peripheral nervous systems, we discuss possible functional roles of these channels in primary sensory neurons.

  14. MicroRNA-Mediated Downregulation of the Potassium Channel Kv4.2 Contributes to Seizure Onset

    Directory of Open Access Journals (Sweden)

    Christina Gross

    2016-09-01

    Full Text Available Seizures are bursts of excessive synchronized neuronal activity, suggesting that mechanisms controlling brain excitability are compromised. The voltage-gated potassium channel Kv4.2, a major mediator of hyperpolarizing A-type currents in the brain, is a crucial regulator of neuronal excitability. Kv4.2 expression levels are reduced following seizures and in epilepsy, but the underlying mechanisms remain unclear. Here, we report that Kv4.2 mRNA is recruited to the RNA-induced silencing complex shortly after status epilepticus in mice and after kainic acid treatment of hippocampal neurons, coincident with reduction of Kv4.2 protein. We show that the microRNA miR-324-5p inhibits Kv4.2 protein expression and that antagonizing miR-324-5p is neuroprotective and seizure suppressive. MiR-324-5p inhibition also blocks kainic-acid-induced reduction of Kv4.2 protein in vitro and in vivo and delays kainic-acid-induced seizure onset in wild-type but not in Kcnd2 knockout mice. These results reveal an important role for miR-324-5p-mediated silencing of Kv4.2 in seizure onset.

  15. Pharmacological Targeting Of Neuronal Kv7.2/3 Channels: A Focus On Chemotypes And Receptor Sites.

    Science.gov (United States)

    Miceli, Francesco; Soldovieri, Maria Virginia; Ambrosino, Paolo; Manocchio, Laura; Medoro, Alessandro; Mosca, Ilaria; Taglialatela, Maurizio

    2017-10-12

    The Kv7 (KCNQ) subfamily of voltage-gated potassium channels consists of 5 members (Kv7.1-5) each showing a characteristic tissue distribution and physiological roles. Given their functional heterogeneity, Kv7 channels represent important pharmacological targets for development of new drugs for neuronal, cardiac and metabolic diseases. In the present manuscript, we focus on describing the pharmacological relevance and the potential therapeutic applications of drugs acting on neuronally-expressed Kv7.2/3 channels, placing particular emphasis on the different modulator chemotypes, and highlighting their pharmacodynamic and, whenever possible, pharmacokinetic peculiarities. The present work is based on an in-depth search of the currently available scientific literature, and on our own experience and knowledge in the field of neuronal Kv7 channel pharmacology. Space limitations impeded to describe the full pharmacological potential of Kv7 channels; thus, we have chosen to focus on neuronal channels composed of Kv7.2 and Kv7.3 subunits, and to mainly concentrate on their involvement in epilepsy. An astonishing heterogeneity in the molecular scaffolds exploitable to develop Kv7.2/3 modulators is evident, with important structural/functional peculiarities of distinct compound classes. In the present work we have attempted to show the current status and growing potential of the Kv7 pharmacology field. We anticipate a bright future for the field, and we express our hopes that the efforts herein reviewed will result in an improved treatment of hyperexcitability (or any other) diseases. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. Compact 250-kV injector system for PIGMI

    International Nuclear Information System (INIS)

    Hamm, R.W.; Stevens, R.R. Jr.; Mueller, D.W.; Lederer, H.M.

    1978-01-01

    A 250-kV proton injector to be used in the development of a linac suitable for medical applications has been constructed. This injector utilizes a spherical Pierce geometry to produce a converging beam. A gas insulated accelerating column is cantilevered on a grounded vacuum system, with a separate high voltage equipment dome connected to a 300-kV Cockcroft-Walton power supply. The injector can be operated locally or remotely, with the remote control accomplished by a microprocessor system linked to a central control minicomputer. This injector has been designed as a low-cost compact system. The design details and the data obtained during initial operation are presented

  17. Regulation of Kv1.4 potassium channels by PKC and AMPK kinases

    DEFF Research Database (Denmark)

    Andersen, Martin Nybo; Skibsbye, Lasse; Saljic, Arnela

    2018-01-01

    around the ubiquitin ligase Nedd4-2. In the present study we examined whether Kv1.4, constituting the cardiac Ito,s current, is subject to similar regulation. In the epithelial Madin-Darby Canine Kidney (MDCK) cell line, which constitutes a highly reproducible model system for addressing membrane...... targeting, we find, by confocal microscopy, that Kv1.4 cell surface expression is downregulated by activation of protein kinase C (PKC) and AMP-activated protein kinase (AMPK). In contrast, manipulating the activities of phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and serum and glucocorticoid......-regulated kinase 1 (SGK1) were without effect on channel localization. The PKC and AMPK-mediated downregulation of Kv1.4 membrane surface localization was confirmed by two-electrode voltage clamp in Xenopus laevis oocytes, where pharmacological activation of PKC and AMPK reduced Kv1.4 current levels. We further...

  18. Risk Analysis Method Based on FMEA for Transmission Line in Lightning Hazards

    Directory of Open Access Journals (Sweden)

    You-Yuan WANG

    2014-05-01

    Full Text Available Failure rate of transmission line and reliability of power system are significantly affected by Lightning meteorological factor. In view of the complexity and variability of Lightning meteorological factors, this paper presents lightning trip-out rate model of transmission line in considering distribution of ground flash density and lightning day hours. Meanwhile, presents a failure rate model of transmission line in different condition, and a risk analysis method for transmission line considering multiple risk factors based on risk quantification. This method takes Lightning meteorological factor as the main evaluation standard, and establishes risk degree evaluation system for transmission line including another five evaluation standard. Put forward the risk indicators by quantify the risk factors based on experience date of transmission line in service. Based on the risk indexes comprehensive evaluation is conducted, and the evaluation result closer to practice is achieved, providing basis for transmission line risk warning and maintenance strategy. Through the risk analysis for 220 kV transmission line in a certain power supply bureau, the effectiveness of the proposed method is validated.

  19. CEBAF 200 kV Inverted Electron Gun

    International Nuclear Information System (INIS)

    Grames, J.M.; Adderley, P.A.; Clark, J.; Hansknecht, J.; Poelker, M.; Stutzman, M.L.; Suleiman, R.; Surles-Law, K.E.L.

    2011-01-01

    Two DC high voltage GaAs photoguns have been built at Jefferson Lab based on a compact inverted insulator design. One photogun provides the polarized electron beam at CEBAF and operates at 130 kV bias voltage. The other gun is used for high average current lifetime studies at a dedicated test facility and has been operated at bias voltage up to 225 kV. The advantages of higher DC voltage for CEBAF include reduced space-charge emittance growth and the potential for prolonged photocathode lifetime. However, a consequence of operating at higher voltages is the increased likelihood of field emission or breakdown, both of which are unacceptable. Highlights of the R and D studies leading toward a production 200keV GaAs photogun for CEBAF will be presented.

  20. 48 CFR 3452.216-71 - Negotiated overhead rates-fixed.

    Science.gov (United States)

    2010-10-01

    ... acceptability of cost allocation methods shall be determined in accordance with part 31 of the Federal... different period, for which the rates apply, and (4) the specific items treated as direct costs or any changes in the items previously agreed to be direct costs. (e) Pending establishment of fixed overhead...

  1. Improved Scheduling Mechanisms for Synchronous Information and Energy Transmission.

    Science.gov (United States)

    Qin, Danyang; Yang, Songxiang; Zhang, Yan; Ma, Jingya; Ding, Qun

    2017-06-09

    Wireless energy collecting technology can effectively reduce the network time overhead and prolong the wireless sensor network (WSN) lifetime. However, the traditional energy collecting technology cannot achieve the balance between ergodic channel capacity and average collected energy. In order to solve the problem of the network transmission efficiency and the limited energy of wireless devices, three improved scheduling mechanisms are proposed: improved signal noise ratio (SNR) scheduling mechanism (IS2M), improved N-SNR scheduling mechanism (INS2M) and an improved Equal Throughput scheduling mechanism (IETSM) for different channel conditions to improve the whole network performance. Meanwhile, the average collected energy of single users and the ergodic channel capacity of three scheduling mechanisms can be obtained through the order statistical theory in Rayleig, Ricean, Nakagami- m and Weibull fading channels. It is concluded that the proposed scheduling mechanisms can achieve better balance between energy collection and data transmission, so as to provide a new solution to realize synchronous information and energy transmission for WSNs.

  2. Major Refit for CERN's 400 kV Substation (Part of the new control and protection system for the 18 kV side)

    CERN Document Server

    2001-01-01

    The 400 kV substation on the Prévessin site brings in the electricity that powers CERN's accelerators and the majority of the Laboratory's installations. It was originally built in the 1970s for the SPS, and is one of only five privately owned 400 kV sub-stations in France. Three of the others belong to the national railway company, SNCF, supplying the Paris-Marseilles TGV line, the other is at the Cadarache research centre near mouth of the Rhone. After nearly thirty years of service, CERN's substation has just undergone a complete overhaul.

  3. The short-circuit test results of 6.9 kV/2.3 kV 400 kVA-class YBCO model transformer with fault current limiting function

    International Nuclear Information System (INIS)

    Tomioka, A.; Bohno, T.; Kakami, S.; Isozaki, M.; Watanabe, K.; Toyama, K.; Sugiyama, S.; Konno, M.; Gosho, Y.; Okamoto, H.; Hayashi, H.; Tsutsumi, T.; Iwakuma, M.; Saito, T.; Tanabe, K.; Shiohara, Y.

    2013-01-01

    Highlights: ► We manufactured the 400 kV A-class YBCO model transformer with FCL function. ► Short-circuit test was performed by applying 6.9 kV on primary side. ► The short-circuit current was limited to 174 A for a prospective current of 559 A. ► It agreed with the design and we also confirmed the I c did not degrade. ► The results suggest the possibility to design YBCO transformers with FCL function. -- Abstract: We are developing an elemental technology for 66/6.9 kV 20 MVA-class superconducting power transformer with fault current limiting function. In order to obtain the characteristics of YBCO conductor when the AC over current supplied to the conductor, the model coils were manufactured with YBCO tapes and tested. Based on these results, we manufactured the 6.9 kV/2.3 kV 400 kVA-class YBCO model transformer with fault current limiting function and performed short-circuit test. At the 0.25 s after short-circuit, the short-circuit current of primary winding was limited to about 174 A for a prospective current of 559 A. It was consistent with the design. The I–V characteristics of the winding did not change before and after the test. We consider the model transformer to be able to withstand AC over-current with the function of current limiting. The results suggest the possibility to design YBCO superconducting transformers with fault current limiting function for practical power grid

  4. Specific Kv1.3 blockade modulates key cholesterol-metabolism-associated molecules in human macrophages exposed to ox-LDL.

    Science.gov (United States)

    Yang, Yong; Wang, Yan-Fu; Yang, Xiao-Fang; Wang, Zhao-Hui; Lian, Yi-Tian; Yang, Ying; Li, Xiao-Wei; Gao, Xiang; Chen, Jian; Shu, Yan-Wen; Cheng, Long-Xian; Liao, Yu-Hua; Liu, Kun

    2013-01-01

    Cholesterol-metabolism-associated molecules, including scavenger receptor class A (SR-A), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), CD36, ACAT1, ABCA1, ABCG1, and scavenger receptor class B type I, can modulate cholesterol metabolism in the transformation from macrophages to foam cells. Voltage-gated potassium channel Kv1.3 has increasingly been demonstrated to play an important role in the modulation of macrophage function. Here, we investigate the role of Kv1.3 in modulating cholesterol-metabolism-associated molecules in human acute monocytic leukemia cell-derived macrophages (THP-1 macrophages) and human monocyte-derived macrophages exposed to oxidized LDL (ox-LDL). Human Kv1.3 and Kv1.5 channels (hKv1.3 and hKv1.5) are expressed in macrophages and form a heteromultimeric channel. The hKv1.3-E314 antibody that we had generated as a specific hKv1.3 blocker inhibited outward delayed rectifier potassium currents, whereas the hKv1.5-E313 antibody that we had generated as a specific hKv1.5 blocker failed. Accordingly, the hKv1.3-E314 antibody reduced percentage of cholesterol ester and enhanced apoA-I-mediated cholesterol efflux in THP-1 macrophages and human monocyte-derived macrophages exposed to ox-LDL. The hKv1.3-E314 antibody downregulated SR-A, LOX-1, and ACAT1 expression and upregulated ABCA1 expression in THP-1 macrophages and human monocyte-derived macrophages. Our results reveal that specific Kv1.3 blockade represents a novel strategy modulating cholesterol metabolism in macrophages, which benefits the treatment of atherosclerotic lesions.

  5. Final environmental assessment for a refinement of the power delivery component of the Southern Nevada Water Authority Treatment and Transmission Facility

    International Nuclear Information System (INIS)

    1998-07-01

    The Southern Nevada Water Authority (SNWA) is designing and constructing a system of regional water supply facilities to meet current and projected water demands and increase system reliability. The existing Southern Nevada Water system is being upgraded with a number of improvements to increase the capacity of the system. However, even the expanded system is expected to be unable to meet projected peak daily water demands by the year 1999. As a result, new facilities are being designed and constructed to operate in conjunction with the upgraded Southern Nevada Water system. These new facilities, known as the Southern Nevada Water Authority Treatment and Transmission Facility (SNWA-TTF), include four primary components: a new raw water intake; new transmission facilities including below ground pipelines, tunnels, and above ground pumping stations; a water treatment facility; and new power supply facilities. Because existing power supplies would not be adequate for the new water treatment facilities, new power facilities, consisting of two new 230 kV-69 kV substations and new 69 and 230 kV power lines, are being constructed. This environmental assessment is specifically on the new power facilities

  6. Modellering og måling af metan-emission fra kvæg

    DEFF Research Database (Denmark)

    Storm, I; Hellwing, Anne Louise Frydendahl; Nielsen, N I

    2011-01-01

    Udvikling af og kendskab til de metoder, der bruges til måling af kvægs metan-emission udgør en vigtig del af forskningen indenfor området. I dette indlæg præsenteres de mest anvendte metoder til måling og estimation af kvægs metan-emission, herunder modeller, in vitro inkubation, kammer-metoder,......-metoder, SF6-metoden og CO2-metoden. De enkelte metoder beskrives og fordele, ulemper og anvendelsesområder sammenlignes. Dette er vigtig baggrundsinformation for forståelse og fortolkning af øvrige forskningsresultater og for at kunne planlægge fremtidige projekter.......Udvikling af og kendskab til de metoder, der bruges til måling af kvægs metan-emission udgør en vigtig del af forskningen indenfor området. I dette indlæg præsenteres de mest anvendte metoder til måling og estimation af kvægs metan-emission, herunder modeller, in vitro inkubation, kammer...

  7. Simplified Antenna Group Determination of RS Overhead Reduced Massive MIMO for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Byung Moo Lee

    2017-12-01

    Full Text Available Massive multiple-input multiple-output (MIMO systems can be applied to support numerous internet of things (IoT devices using its excessive amount of transmitter (TX antennas. However, one of the big obstacles for the realization of the massive MIMO system is the overhead of reference signal (RS, because the number of RS is proportional to the number of TX antennas and/or related user equipments (UEs. It has been already reported that antenna group-based RS overhead reduction can be very effective to the efficient operation of massive MIMO, but the method of deciding the number of antennas needed in each group is at question. In this paper, we propose a simplified determination scheme of the number of antennas needed in each group for RS overhead reduced massive MIMO to support many IoT devices. Supporting many distributed IoT devices is a framework to configure wireless sensor networks. Our contribution can be divided into two parts. First, we derive simple closed-form approximations of the achievable spectral efficiency (SE by using zero-forcing (ZF and matched filtering (MF precoding for the RS overhead reduced massive MIMO systems with channel estimation error. The closed-form approximations include a channel error factor that can be adjusted according to the method of the channel estimation. Second, based on the closed-form approximation, we present an efficient algorithm determining the number of antennas needed in each group for the group-based RS overhead reduction scheme. The algorithm depends on the exact inverse functions of the derived closed-form approximations of SE. It is verified with theoretical analysis and simulation that the proposed algorithm works well, and thus can be used as an important tool for massive MIMO systems to support many distributed IoT devices.

  8. Molecular Expression and Pharmacological Evidence for a Functional Role of Kv7 Channel Subtypes in Guinea Pig Urinary Bladder Smooth Muscle

    Science.gov (United States)

    Afeli, Serge A. Y.; Malysz, John; Petkov, Georgi V.

    2013-01-01

    Voltage-gated Kv7 (KCNQ) channels are emerging as essential regulators of smooth muscle excitability and contractility. However, their physiological role in detrusor smooth muscle (DSM) remains to be elucidated. Here, we explored the molecular expression and function of Kv7 channel subtypes in guinea pig DSM by RT-PCR, qRT-PCR, immunohistochemistry, electrophysiology, and isometric tension recordings. In whole DSM tissue, mRNAs for all Kv7 channel subtypes were detected in a rank order: Kv7.1~Kv7.2Kv7.3~Kv7.5Kv7.4. In contrast, freshly-isolated DSM cells showed mRNA expression of: Kv7.1~Kv7.2Kv7.5Kv7.3~Kv7.4. Immunohistochemical confocal microscopy analyses of DSM, conducted by using co-labeling of Kv7 channel subtype-specific antibodies and α-smooth muscle actin, detected protein expression for all Kv7 channel subtypes, except for the Kv7.4, in DSM cells. L-364373 (R-L3), a Kv7.1 channel activator, and retigabine, a Kv7.2-7.5 channel activator, inhibited spontaneous phasic contractions and the 10-Hz electrical field stimulation (EFS)-induced contractions of DSM isolated strips. Linopiridine and XE991, two pan-Kv7 (effective at Kv7.1-Kv7.5 subtypes) channel inhibitors, had opposite effects increasing DSM spontaneous phasic and 10 Hz EFS-induced contractions. EFS-induced DSM contractions generated by a wide range of stimulation frequencies were decreased by L-364373 (10 µM) or retigabine (10 µM), and increased by XE991 (10 µM). Retigabine (10 µM) induced hyperpolarization and inhibited spontaneous action potentials in freshly-isolated DSM cells. In summary, Kv7 channel subtypes are expressed at mRNA and protein levels in guinea pig DSM cells. Their pharmacological modulation can control DSM contractility and excitability; therefore, Kv7 channel subtypes provide potential novel therapeutic targets for urinary bladder dysfunction. PMID:24073284

  9. Break-down stage in a 20 kV coaxial gun

    International Nuclear Information System (INIS)

    Feugeas, J.; Massa, M.; VonPamel, O.

    1984-01-01

    The electrical break-down of hydrogen in a coaxial electrode system (similar to Mather-type Plasma Focus) was studied for a wide range of pressures. A squirrel's cage outer electrode (cathode) of 50 mm of diameter was used to allow lateral views of the discharge, with an inner electrode (anode) of 17 mm of diameter and a pyrex sleeve of 25 mm length as insulator located at the breech of the gun. A low inductance plane plate transmission line was discharged (20 kV) through a spark gap switch over the system, with a typical peak current of 22 kA, reached after 80 ns from onset of the discharge. The fine structure of the luminous current sheath was studied by frontal and lateral open shutter photographs and by monitoring the current distribution along and across the electrodes gap. The authors tests determine the relative importance of the resistivity related to particle collision effects (αiota) and of the inductive resistivity (α L-center dot) during the break-down stage (iota=length of break-down path, L=inductance)

  10. 35-kV GaAs subnanosecond photoconductive switches

    Science.gov (United States)

    Pocha, Michael D.; Druce, Robert L.

    1990-12-01

    High-voltage, fast-pulse generation using GaAs photoconductive switches is investigated. It is possible to to generate 35-kV pulses with risetimes as short as 135 ps using 5-mm gap switches, and electric field hold-off of greater than 100 kV/cm is achieved. An approximately 500-ps FWHM on/off electrical pulse is generated with an amplitude of approximately 3 kV using neutron-irradiated GaAs having short carrier lifetimes. Experimental results are described, and fabrication of switches and the diagnostics used to measure these fast signals are discussed. Experience with the nonlinear lock-on and avalanche modes of operation observed in GaAs is also described.

  11. High voltage direct current (HVDC) link between the power networks of Italy and Greece

    International Nuclear Information System (INIS)

    Carcano, C.; Oliva, P.; Voyatzakis, J.

    1996-01-01

    Interconnection between the power networks of Italy and Greece has long been declared of European interest. The link, which will directly connect Greece with the power network of UCPTE, is perfectly in line with the targets of the European Union in terms of trans-European power networks. The interconnection, which benefits of a financial contribution of the EU, will rely on a 400 kV d.c. transmission system with one submarine cable between the Italian and Greek coasts, overhead lines on land, d.c./a.c. conversion stations, return of current to sea via marine electrodes. The main technical features of the project are described, highlighting its most significant design concepts. (author)

  12. System impact assessment report 115 kV interconnection between Cornwall system and Hydro One : final report

    International Nuclear Information System (INIS)

    2005-01-01

    Cornwall Electric (CE) is the local distribution company that serves the City of Cornwall, Ontario. The utility can be supplied from either Hydro Quebec, New York ISO or the IESO. CE has proposed to connect Rosemount, McConnell and Courtaulds substations to the IESO-controlled grid in order to obtain access to the competitively priced electricity in Ontario. The load connected to the 2 substations peaks in winter at about 100 MW. The 2 substations will be connected in stages. Only 40 MW of load from the Rosemount substation will be connected initially, followed by up to 100 MW from the McConnell and Courtaulds substation at a later date. The connection will be made through a circuit that taps into the St. Lawrence transmission station in Ontario. A new circuit will also be built and strung on existing towers. This document described the requirements for under-frequency load shedding; voltage reduction facilities; power factor; on-line monitoring; and system protections. According to data provided by Hydro One, the circuit is adequately rated to accommodate connection of the load from the Rosemount and McConnell and Courtaulds substations with no thermal overloading concerns. Winter load conditions were also considered. However, the IESO noted a potential reliability concern in the event that the Cardinal Power generating station is out of service and only one of the transformers connecting St. Lawrence 230 kV bus to St. Lawrence 115 kV bus is in service. However, the power transfers rated at 250 MVA are within the continuous rating of one transformer. It was concluded that the connection of the new load does not have an impact on the short circuit current at the St. Lawrence transmission station. The continuous thermal rating of the circuit is considered to be adequate for the proposed 100 MW of load transfer and the rating of the new line is sufficient to supply the total load at McConnell and Courtaulds. The ratings of the new disconnect switches meet market

  13. Recent progress of the improved magnetically insulated transmission line oscillator.

    Science.gov (United States)

    Fan, Yu-Wei; Zhong, Hui-Huang; Li, Zhi-Qiang; Shu, Ting; Zhang, Jian-De; Liu, Jin-Liang; Yang, Jian-Hua; Zhang, Jun; Yuan, Cheng-Wei; Luo, Ling

    2008-03-01

    The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube driven by a 550 kV, 57 kA, 50 ns electron beam. It has allowed us to generate 2.4 GW pulse of 22 ns duration. The recent progress of the improved MILO is presented in this paper. First, a field shaper cathode is introduced into the improved MILO to avoid the cathode flares in the triple point region. The experimental results show that the cathode flares are avoided, so the lifetime of the velvet cathode is longer than that of the taper cathode. Furthermore, the shot-to-shot reproducibility is better than that of the taper cathode. Second, In order to prolong the pulse duration and increase the radiated microwave power, a self-built 600 kV, 10 Omega, 80 ns pulser: SPARK-03 is employed to drive the improved MILO. Simulation and experimental investigation are performed. In simulation, when the improved MILO is driven by a 600 kV, 57 kA electron beam, high-power microwave is generated with output power of 4.15 GW, frequency of 1.76 GHz, and relevant power conversion efficiency of 12.0%. In experiments, when the diode voltage is 550 kV and current is 54 kA, the measured results are that the radiated microwave power is above 3.1 GW, the pulse duration is above 40 ns, the microwave frequency is about 1.755 GHz, and the power conversion efficiency is about 10.4%.

  14. Draft environmental impact statement - BPA/Lower Valley transmission project

    International Nuclear Information System (INIS)

    1997-06-01

    Bonneville Power Administration and Lower Valley Power and Light, Inc., propose to solve a voltage stability problem in the Jackson and Afton, Wyoming areas. For the Agency Proposed Action, BPA and Lower Valley would construct a new 115-kV line from BPA's Swan Valley Substation near Swan Valley in Bonneville County, Idaho about 58 km (36 miles) east to BPA's Teton Substation near Jackson in Teton County, Wyoming. The new line would be next to an existing 115-kV line. Most of the line would be supported by a mix of single-circuit wood pole H-frame structures would be used. The Single-Circuit Line Alternative has all the components of the Agency Proposed Action except that the entire line would be supported by single-circuit structures. The Short Line Alternative has all the components of the Single-Circuit Line Alternative except it would then be removed. For the Static Var Compensation Alternative, BPA would install a Static Var Compensator (SVC) at Teton or Jackson Substation. An SVC is a group of electrical equipment placed at a substation to help control voltage on a transmission system. The No Action Alternative assumes that no new transmission line is built, and no other equipment is added to the transmission system. The USFS (Targhee and Bridger-Teton National Forests) must select al alternative based on their needs and objectives, decide if the project complies with currently approved forest plans, decide if special use permits or easements are needed for construction, operation, and maintenance of project facilities, and decide if they would issue special use permits and letters of consent to grant easements for the project

  15. Priority image transmission in wireless sensor networks

    International Nuclear Information System (INIS)

    Nasri, M.; Helali, A.; Sghaier, H.; Maaref, H.

    2011-01-01

    The emerging technology during the last years allowed the development of new sensors equipped with wireless communication which can be organized into a cooperative autonomous network. Some application areas for wireless sensor networks (WSNs) are home automations, health care services, military domain, and environment monitoring. The required constraints are limited capacity of processing, limited storage capability, and especially these nodes are limited in energy. In addition, such networks are tiny battery powered which their lifetime is very limited. During image processing and transmission to the destination, the lifetime of sensor network is decreased quickly due to battery and processing power constraints. Therefore, digital image transmissions are a significant challenge for image sensor based Wireless Sensor Networks (WSNs). Based on a wavelet image compression, we propose a novel, robust and energy-efficient scheme, called Priority Image Transmission (PIT) in WSN by providing various priority levels during image transmissions. Different priorities in the compressed image are considered. The information for the significant wavelet coeffcients are transmitted with higher quality assurance, whereas relatively less important coefficients are transmitted with lower overhead. Simulation results show that the proposed scheme prolongs the system lifetime and achieves higher energy efficiency in WSN with an acceptable compromise on the image quality.

  16. Estimation of flashover voltage probability of overhead line insulators under industrial pollution, based on maximum likelihood method

    International Nuclear Information System (INIS)

    Arab, M.N.; Ayaz, M.

    2004-01-01

    The performance of transmission line insulator is greatly affected by dust, fumes from industrial areas and saline deposit near the coast. Such pollutants in the presence of moisture form a coating on the surface of the insulator, which in turn allows the passage of leakage current. This leakage builds up to a point where flashover develops. The flashover is often followed by permanent failure of insulation resulting in prolong outages. With the increase in system voltage owing to the greater demand of electrical energy over the past few decades, the importance of flashover due to pollution has received special attention. The objective of the present work was to study the performance of overhead line insulators in the presence of contaminants such as induced salts. A detailed review of the literature and the mechanisms of insulator flashover due to the pollution are presented. Experimental investigations on the behavior of overhead line insulators under industrial salt contamination are carried out. A special fog chamber was designed in which the contamination testing of insulators was carried out. Flashover behavior under various degrees of contamination of insulators with the most common industrial fume components such as Nitrate and Sulphate compounds was studied. Substituting the normal distribution parameter in the probability distribution function based on maximum likelihood develops a statistical method. The method gives a high accuracy in the estimation of the 50% flashover voltage, which is then used to evaluate the critical flashover index at various contamination levels. The critical flashover index is a valuable parameter in insulation design for numerous applications. (author)

  17. Protein kinase A stimulates Kv7.1 surface expression by regulating Nedd4-2-dependent endocytic trafficking

    DEFF Research Database (Denmark)

    Andersen, Martin Nybo; Hefting, Louise Leth; Steffensen, Annette Buur

    2015-01-01

    The potassium channel Kv7.1 plays critical physiological roles in both heart and epithelial tissues. In heart, Kv7.1 and the accessory subunit KCNE1 forms the IKs current, which is enhanced by PKA mediated phosphorylation. The observed current increase requires both phosphorylation of Kv7.......1 and the presence of KCNE1. However, PKA also stimulates Kv7.1 currents in epithelial tissues, such as colon, where the channel does not co-assemble with KCNE1. Here, we demonstrate that PKA activity significantly impacts the subcellular localization of Kv7.1 in Madin Darby Canine Kidney cells. While PKA inhibition...... reduced the fraction of channels at the cell surface, PKA activation increased it. We show that PKA inhibition lead to intracellular accumulation of Kv7.1 in late endosomes/lysosomes. By mass spectroscopy we identified eight phosphorylated residues on Kv7.1, however, none appeared to play a role...

  18. miR-1 is increased in pulmonary hypertension and downregulates Kv1.5 channels in rat pulmonary arteries.

    Science.gov (United States)

    Mondejar-Parreño, Gema; Callejo, María; Barreira, Bianca; Morales-Cano, Daniel; Esquivel-Ruiz, Sergio; Moreno, Laura; Cogolludo, Angel; Perez-Vizcaino, Francisco

    2018-05-02

    ■The expression of miR-1 is increased in lungs from the Hyp/Su5416 PAH rat model. ■PASMC from this animal model are more depolarised and show decreased expression and activity of Kv1.5. ■miR-1 directly targets Kv1.5 channels, reduces Kv1.5 activity and induces membrane depolarization. ■Antagomir-1 prevents Kv1.5 channel downregulation and the depolarization induced by hypoxia/Su5416 exposition. Impairment of voltage-dependent potassium channel (Kv) plays a central role in the development of cardiovascular diseases, including pulmonary arterial hypertension (PAH). MicroRNAs (miRNAs) are non-coding RNAs that regulate gene expression by binding to the 3'-UTR region of specific mRNAs. The aim of this study was to analyze the effects of miR-1 on Kv channel function in pulmonary arteries (PA). Kv channel activity was studied in PA from healthy animals transfected with miR-1 or scrambled-miR. Kv currents were studied using the whole-cell configuration of patch-clamp technique. The characterization of the Kv1.5 currents was performed with the selective inhibitor DPO-1. miR-1 expression was increased and Kv1.5 channels were decreased in lungs from a rat model of PAH induced by hypoxia and Su5416. miR-1 transfection increased cell capacitance, reduced Kv1.5 currents and induced membrane depolarization in isolated pulmonary artery smooth muscle cells (PASMCs). Luciferase reporter assay indicated that KCNA5, which encodes Kv1.5 channels, is a direct target gene of miR-1. Incubation of PA with Su5416 and hypoxia (3% O 2 ) increased miR-1 and induced a decline in Kv1.5 currents, which was prevented by antagomiR-1. In conclusion, these data indicate that miR-1 induces PASMC hypertrophy and reduces the activity and expression of Kv channels, suggesting a pathophysiological role in PAH. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. 250 kV 6 mA compact Cockcroft-Walton high-voltage power supply

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhan-Wen; Su, Xiao-Dong; Wei, Zhen; Huang, Zhi-Wu; Miao, Tian-You; Su, Tong-Ling [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Lu, Xiao-Long; Wang, Jun-Run; Yao, Ze-En, E-mail: zeyao@lzu.edu.cn [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

    2016-08-15

    A compact power supply system for a compact neutron generator has been developed. A 4-stage symmetrical Cockcroft-Walton circuit is adopted to produce 250 kV direct current high-voltage. A 2-stage 280 kV isolation transformer system is used to drive the ion source power supply. For a compact structure, safety, and reliability during the operation, the Cockcroft-Walton circuit and the isolation transformer system are enclosed in an epoxy vessel containing the transformer oil whose size is about ∅350 mm × 766 mm. Test results indicate that the maximum output voltage of the power supply is 282 kV, and the stability of the output voltage is better than 0.63% when the high voltage power supply is operated at 250 kV, 6.9 mA with the input voltage varying ±10%.

  20. The pan-Kv7 (KCNQ) Channel Opener Retigabine Inhibits Striatal Excitability by Direct Action on Striatal Neurons In Vivo

    DEFF Research Database (Denmark)

    Hansen, Henrik H; Weikop, Pia; Mikkelsen, Maria D

    2017-01-01

    Central Kv7 (KCNQ) channels are voltage-dependent potassium channels composed of different combinations of four Kv7 subunits, being differently expressed in the brain. Notably, striatal dopaminergic neurotransmission is strongly suppressed by systemic administration of the pan-Kv7 channel opener ...... by acute systemic haloperidol administration in the rat. The relative mRNA levels of Kv7 subunits in the rat striatum were found to be Kv7.2 = Kv7.3 = Kv7.5 > >Kv7.4. These data suggest that intrastriatal Kv7 channels play a direct role in regulating striatal excitability in vivo....

  1. Analysis of operating conditions of the voltage transformer

    Directory of Open Access Journals (Sweden)

    Fastiy G. P.

    2017-12-01

    Full Text Available In electrical networks, constant monitoring of the electrical equipment operation is necessary. To accomplish this task, current transformers and voltage transformers (VT are used, on which the accuracy of electrical measurements, electricity metering, and the reliability of the emergency control system depend. The results of the analysis of the conditions for forming the magnetization of a voltage transformer in the mode with unilateral connection of overhead transmission lines, as well as variants of violations in the 110 kV network that may exist for a relatively long time have been presented. It should be noted that the considered network has its own peculiarities: the overhead transmission lines connected in series have a significant length and a low level of load, which may be a condition for the appearance of a transmission lines capacitive effect (the Ferranti effect, the latter can cause overvoltage. Overvoltage occurs when the operating modes are temporary in terms of operation, adverse combinations of network parameters take place, and can continue until the circuit and network modes change. Most often they appear in asymmetric modes, with short circuits to ground, etc. Asymmetric modes caused by incomplete-phase commutations and wire breaks on the overhead line, as well as wire breaks with subsequent disconnection of power transformers that can affect the voltage level on the VT have been considered. The possibility of VT magnetizing with a prolonged voltage rise in symmetric modes, namely, the manifestation of the Ferranti effect with various loads at substations up to complete switching-off and power transformers switching off has been investigated. The analysis of the measuring voltage transformer operating conditions has been based on materials provided by the "Kolenergo" services.

  2. KV4.3 N-terminal deletion mutant Δ2–39

    Science.gov (United States)

    Hovind, Laura J; Skerritt, Matthew R

    2011-01-01

    Gating transitions in the KV4.3 N-terminal deletion mutant Δ2–39 were characterized in the absence and presence of KChIP2b. We particularly focused on gating characteristics of macroscopic (open state) versus closed state inactivation (CSI) and recovery. In the absence of KChIP2b Δ2–39 did not significantly alter the steady-state activation “a4” relationship or general CSI characteristics, but it did slow the kinetics of deactivation, macroscopic inactivation and macroscopic recovery. Recovery kinetics (for both WT KV4.3 and Δ2–39) were complicated and displayed sigmoidicity, a process which was enhanced by Δ2–39. Deletion of the proximal N-terminal domain therefore appeared to specifically slow mechanisms involved in regulating gating transitions occurring after the channel open state(s) had been reached. In the presence of KChIP2b Δ2–39 recovery kinetics (from both macroscopic and CSI) were accelerated, with an apparent reduction in initial sigmoidicity. Hyperpolarizing shifts in both “a4” and isochronal inactivation “i” were also produced. KChIP2b-mediated remodeling of KV4.3 gating transitions was therefore not obligatorily dependent upon an intact N-terminus. To account for these effects we propose that KChIP2 regulatory domains exist in KV4.3 α subunit regions outside of the proximal N-terminal. In addition to regulating macroscopic inactivation, we also propose that the KV4.3 N-terminus may act as a novel regulator of deactivation-recovery coupling. PMID:21057209

  3. Physiological role of Kv1.3 channel in T lymphocyte cell investigated quantitatively by kinetic modeling.

    Directory of Open Access Journals (Sweden)

    Panpan Hou

    Full Text Available Kv1.3 channel is a delayed rectifier channel abundant in human T lymphocytes. Chronic inflammatory and autoimmune disorders lead to the over-expression of Kv1.3 in T cells. To quantitatively study the regulatory mechanism and physiological function of Kv1.3 in T cells, it is necessary to have a precise kinetic model of Kv1.3. In this study, we firstly established a kinetic model capable to precisely replicate all the kinetic features for Kv1.3 channels, and then constructed a T-cell model composed of ion channels including Ca2+-release activated calcium (CRAC channel, intermediate K+ (IK channel, TASK channel and Kv1.3 channel for quantitatively simulating the changes in membrane potentials and local Ca2+ signaling messengers during activation of T cells. Based on the experimental data from current-clamp recordings, we successfully demonstrated that Kv1.3 dominated the membrane potential of T cells to manipulate the Ca2+ influx via CRAC channel. Our results revealed that the deficient expression of Kv1.3 channel would cause the less Ca2+ signal, leading to the less efficiency in secretion. This was the first successful attempt to simulate membrane potential in non-excitable cells, which laid a solid basis for quantitatively studying the regulatory mechanism and physiological role of channels in non-excitable cells.

  4. TNB high tension overhead cables: is their electromagnetic field hazard real?

    International Nuclear Information System (INIS)

    Roha Tukimin; Mohd Yusof Mohd Ali; Mohamad Amirul Nizam

    2005-01-01

    Extremely low frequency electromagnetic fields (ELF, EMF) fall under the category of non-ionising radiation. We live in an electromagnetic environment generated by both natural (earths magnetic field, sunlight) and man-made. One of the man-made sources which produces significant electromagnetic fields (EMF) is the electric power supply system. In modern time, electricity has become an essential part of our lives. Electric power supply system, which includes generation, transmission and distribution of the electricity, produces extremely low frequency electromagnetic fields (ELF EMF) that travel along the overhead cables at 50 cycles per second (50 Hz).They are a form of energy that travels in space as electromagnetic waves. In spite of the fact that ELF EMF are very weak electromagnetic emission, they are believed to be hazardous to human health because of their ability to induce current and to initiate energy deposition in the body, which may eventually lead to increase in body temperature, behavioral changes and perhaps cancer in the long term. Due to their potential of causing such health hazard, several companies have approached and requested MINT to carry out surveys and safety assessments of their land properties, which are located close to the transmission lines. This paper highlights some of the works that had been carried out by MINT based on the requests received. They were performed based on international standard IEEE procedures protocols using properly calibrated portable ELF instruments. The results confirmed that ELF EMF did present at the survey sites but were very much lower than the permissible exposure limit recommended for members of public (1000 m Gauss / 5000 V/m). They were found to vary against measurements locations, which were strongly influenced by vertical and horizontal distances from the cables and by the presence of other objects like building and trees. (Author)

  5. A Degree Distribution Optimization Algorithm for Image Transmission

    Science.gov (United States)

    Jiang, Wei; Yang, Junjie

    2016-09-01

    Luby Transform (LT) code is the first practical implementation of digital fountain code. The coding behavior of LT code is mainly decided by the degree distribution which determines the relationship between source data and codewords. Two degree distributions are suggested by Luby. They work well in typical situations but not optimally in case of finite encoding symbols. In this work, the degree distribution optimization algorithm is proposed to explore the potential of LT code. Firstly selection scheme of sparse degrees for LT codes is introduced. Then probability distribution is optimized according to the selected degrees. In image transmission, bit stream is sensitive to the channel noise and even a single bit error may cause the loss of synchronization between the encoder and the decoder. Therefore the proposed algorithm is designed for image transmission situation. Moreover, optimal class partition is studied for image transmission with unequal error protection. The experimental results are quite promising. Compared with LT code with robust soliton distribution, the proposed algorithm improves the final quality of recovered images obviously with the same overhead.

  6. The Seismic Analysis of 800kV Gas Insulated Switchgear (GIS) for the Dangjin Thermal Plant

    Energy Technology Data Exchange (ETDEWEB)

    Shin, I.H.; Song, W.P.; Kweon, K.Y. [Hyosung Corporation (Korea)

    1999-05-01

    800kV GIS (Gas Insulated Switchgear) which was first developed in korea at Dec. 1998 and is going to be installed in the dangjin thermal plant. We checked the stability of 800kV GIS under seismic load. pro-ENGINEER and PATRAN were used for modeling exactly 800kV GIS geometry. The 800kV GIS was modeled as shell elements for the enclosures and beam elements for the conductors and the support insulators. (author). 2 refs., 9 figs., 2 tabs.

  7. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-62) - Rocky Reach - Maple Valley

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Mark A. [Bonneville Power Administration (BPA), Portland, OR (United States)

    2002-04-16

    Vegetation Management along the Rocky Reach – Maple Valley No. 1 Transmission Line ROW from structure 98/2 to structure 110/1. The transmission line is a 500 kV line. BPA proposes to clear targeted vegetation along access roads and around tower structures that may impede the operation and maintenance of the subject transmission line. BPA plans to conduct vegetation management along existing access road and around structure landings for the purpose of maintaining access to structures site. All work will be in accordance with the National Electrical Safety Code and BPA standards.

  8. Spectral and Energy Efficient Low-Overhead Uplink and Downlink Channel Estimation for 5G Massive MIMO Systems

    Directory of Open Access Journals (Sweden)

    Imran Khan

    2018-01-01

    Full Text Available Uplink and Downlink channel estimation in massive Multiple Input Multiple Output (MIMO systems is an intricate issue because of the increasing channel matrix dimensions. The channel feedback overhead using traditional codebook schemes is very large, which consumes more bandwidth and decreases the overall system efficiency. The purpose of this paper is to decrease the channel estimation overhead by taking the advantage of sparse attributes and also to optimize the Energy Efficiency (EE of the system. To cope with this issue, we propose a novel approach by using Compressed-Sensing (CS, Block Iterative-Support-Detection (Block-ISD, Angle-of-Departure (AoD and Structured Compressive Sampling Matching Pursuit (S-CoSaMP algorithms to reduce the channel estimation overhead and compare them with the traditional algorithms. The CS uses temporal-correlation of time-varying channels to produce Differential-Channel Impulse Response (DCIR among two CIRs that are adjacent in time-slots. DCIR has greater sparsity than the conventional CIRs as it can be easily compressed. The Block-ISD uses spatial-correlation of the channels to obtain the block-sparsity which results in lower pilot-overhead. AoD quantizes the channels whose path-AoDs variation is slower than path-gains and such information is utilized for reducing the overhead. S-CoSaMP deploys structured-sparsity to obtain reliable Channel-State-Information (CSI. MATLAB simulation results show that the proposed CS based algorithms reduce the feedback and pilot-overhead by a significant percentage and also improve the system capacity as compared with the traditional algorithms. Moreover, the EE level increases with increasing Base Station (BS density, UE density and lowering hardware impairments level.

  9. Online Location of Faults on AC Cables in Underground Transmission Systems

    DEFF Research Database (Denmark)

    Jensen, Christian Flytkjær

    under fault conditions well, but the accuracy of the calculated impedance is low for fault location purposes. The neural networks can therefore not be trained and no impedance-based fault location method can be used for crossbonded cables or hybrid lines. The use of travelling wave-based methods...... connection to verify the proposed method. Faults, at reduced a voltage are artificially applied in the cable system and the transient response is measured at two terminals at the cable’s ends. The measurements are time-synchronised and it is found that a very accurate estimation of the fault location can......A transmission grid is normally laid out as an almost pure overhead line (OHL) network. The introduction of transmission voltage level XLPE cables and the increasing interest in the environmental impact of OHL has resulted in an increasing interest in the use of underground cables on transmission...

  10. Functional and Molecular Evidence for Kv7 Channel Subtypes in Human Detrusor from Patients with and without Bladder Outflow Obstruction

    DEFF Research Database (Denmark)

    Svalø, Julie; Sheykhzade, Majid; Nordling, Jørgen

    2015-01-01

    The aim of the study was to investigate whether Kv7 channels and their ancillary β-subunits, KCNE, are functionally expressed in the human urinary bladder. Kv7 channels were examined at the molecular level and by functional studies using RT-qPCR and myography, respectively. We found mRNA expressi...... between Kv7 channels and β-adrenoceptors in the human urinary bladder. The performed gene expression analysis combined with the organ bath studies imply that compounds that activate Kv7 channels could be useful for treatment of overactive bladder syndrome.......The aim of the study was to investigate whether Kv7 channels and their ancillary β-subunits, KCNE, are functionally expressed in the human urinary bladder. Kv7 channels were examined at the molecular level and by functional studies using RT-qPCR and myography, respectively. We found mRNA expression...... (activator of Kv7.1 channels, 10 μM) and ML213 (activator of Kv7.2, Kv7.4, Kv7.4/7.5 and Kv7.5 channels, 10 μM), reduced the tone of 1 μM carbachol pre-constricted bladder strips. XE991 (blocker of Kv7.1-7.5 channels, 10 μM) had opposing effects as it increased contractions achieved with 20 mM KPSS...

  11. Specific Kv1.3 blockade modulates key cholesterol-metabolism-associated molecules in human macrophages exposed to ox-LDL[S

    Science.gov (United States)

    Yang, Yong; Wang, Yan-Fu; Yang, Xiao-Fang; Wang, Zhao-Hui; Lian, Yi-Tian; Yang, Ying; Li, Xiao-Wei; Gao, Xiang; Chen, Jian; Shu, Yan-Wen; Cheng, Long-Xian; Liao, Yu-Hua; Liu, Kun

    2013-01-01

    Cholesterol-metabolism-associated molecules, including scavenger receptor class A (SR-A), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), CD36, ACAT1, ABCA1, ABCG1, and scavenger receptor class B type I, can modulate cholesterol metabolism in the transformation from macrophages to foam cells. Voltage-gated potassium channel Kv1.3 has increasingly been demonstrated to play an important role in the modulation of macrophage function. Here, we investigate the role of Kv1.3 in modulating cholesterol-metabolism-associated molecules in human acute monocytic leukemia cell-derived macrophages (THP-1 macrophages) and human monocyte-derived macrophages exposed to oxidized LDL (ox-LDL). Human Kv1.3 and Kv1.5 channels (hKv1.3 and hKv1.5) are expressed in macrophages and form a heteromultimeric channel. The hKv1.3-E314 antibody that we had generated as a specific hKv1.3 blocker inhibited outward delayed rectifier potassium currents, whereas the hKv1.5-E313 antibody that we had generated as a specific hKv1.5 blocker failed. Accordingly, the hKv1.3-E314 antibody reduced percentage of cholesterol ester and enhanced apoA-I-mediated cholesterol efflux in THP-1 macrophages and human monocyte-derived macrophages exposed to ox-LDL. The hKv1.3-E314 antibody downregulated SR-A, LOX-1, and ACAT1 expression and upregulated ABCA1 expression in THP-1 macrophages and human monocyte-derived macrophages. Our results reveal that specific Kv1.3 blockade represents a novel strategy modulating cholesterol metabolism in macrophages, which benefits the treatment of atherosclerotic lesions. PMID:23099443

  12. CIAE 600 kV ns pulse neutron generator

    International Nuclear Information System (INIS)

    Shen Guanren; Guan Xialing; Chen Hongtao

    2001-01-01

    The overall composition of CIAE 600 kV ns Pulse Neutron Generator (CPNG) are introduced, and its characteristic, main technological performance and application were also given. CPNG consists of high voltage power supply with highest output voltage 600 kV, direct current 15 mA, stability and ripple ≤0.1%, 2214 mm x 1604 mm x 1504 mm stainless steel high voltage electrode, built in head equipment uniform field accelerating tube, ns pulsed installation, turbomolecular vacuum pump system and drift pipes at 0 degree and 45 degree. Its characteristics are: (1) high current beam; (2) high current beam ns pulsed installation made use of low energy for chopper and high energy for buncher; (3) compactly laid out and simple in structure

  13. Electrostatic induction under the Tanashi test transmission line

    Energy Technology Data Exchange (ETDEWEB)

    Kitani, Y; Yokata, S

    1964-06-01

    Experimental results are given on the electrostatic voltage induced in small and medium-sized motorcars under the Tanashi 800 kV Test Transmission Line, which is of horizontal arrangement, 200 m span, four bundle conductors and average height of 13.52 m. The induced voltage was measured between 1600 and 3000 V under the line voltage of 520 kV. The voltage and current were measured with four kinds of model motorcars in air and water, and results of the measurements are compared with those of actual measurements with good agreements. The values of capacity and leakage resistance, whose parallel circuit was considered to represent an equivalent circuit of the motorcar, were measured with a Maxwell-Wien bridge at frequencies between 30 and 1000 c/s. It was found that the values at 60 c/s were measured to be approximately six or seven times higher than its values at 1000 c/s, and that new tires have higher conductivities than the old ones, reducing the electrostatic induction voltage by a large amount.

  14. Kv2 Ion Channels Determine the Expression and Localization of the Associated AMIGO-1 Cell Adhesion Molecule in Adult Brain Neurons

    Directory of Open Access Journals (Sweden)

    Hannah I. Bishop

    2018-01-01

    Full Text Available Voltage-gated K+ (Kv channels play important roles in regulating neuronal excitability. Kv channels comprise four principal α subunits, and transmembrane and/or cytoplasmic auxiliary subunits that modify diverse aspects of channel function. AMIGO-1, which mediates homophilic cell adhesion underlying neurite outgrowth and fasciculation during development, has recently been shown to be an auxiliary subunit of adult brain Kv2.1-containing Kv channels. We show that AMIGO-1 is extensively colocalized with both Kv2.1 and its paralog Kv2.2 in brain neurons across diverse mammals, and that in adult brain, there is no apparent population of AMIGO-1 outside of that colocalized with these Kv2 α subunits. AMIGO-1 is coclustered with Kv2 α subunits at specific plasma membrane (PM sites associated with hypolemmal subsurface cisternae at neuronal ER:PM junctions. This distinct PM clustering of AMIGO-1 is not observed in brain neurons of mice lacking Kv2 α subunit expression. Moreover, in heterologous cells, coexpression of either Kv2.1 or Kv2.2 is sufficient to drive clustering of the otherwise uniformly expressed AMIGO-1. Kv2 α subunit coexpression also increases biosynthetic intracellular trafficking and PM expression of AMIGO-1 in heterologous cells, and analyses of Kv2.1 and Kv2.2 knockout mice show selective loss of AMIGO-1 expression and localization in neurons lacking the respective Kv2 α subunit. Together, these data suggest that in mammalian brain neurons, AMIGO-1 is exclusively associated with Kv2 α subunits, and that Kv2 α subunits are obligatory in determining the correct pattern of AMIGO-1 expression, PM trafficking and clustering.

  15. Design optimization of the 100 kV HV bushing for ITER-DNB

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Sejal, E-mail: sshah@iter-india.org [ITER-India, Institute for Plasma Research, Gandhinagar 382025, Gujarat (India); Rajesh, S. [ITER-India, Institute for Plasma Research, Gandhinagar 382025, Gujarat (India); Microelectronics and Materials Physics Laboratories, P.O. Box 4500, FIN-90014 University of Oulu (Finland); Srusti, B. [DesignTech Systems Ltd, Banjara Hills, Hyderabad, Andhra Pradesh 500034 (India); Bandyopadhyay, M.; Rotti, C.; Singh, M.J.; Roopesh, G.; Chakraborty, A.K. [ITER-India, Institute for Plasma Research, Gandhinagar 382025, Gujarat (India); Schunke, B.; Hemsworth, R.; Chareyre, J. [ITER Organization, Route de Vinon sur Verdon, 13115 St. Paul lez Durance (France)

    2011-10-15

    The 100 kV bushing of the Diagnostic Neutral Beam (DNB) injector is a cylindrical feedthrough which forms the interface between the gas insulated transmission line and the torus primary vacuum and provides all necessary services to the beam source. All conventions for safety, voltage holding requirement, vacuum compatibility and the choice of materials have been addressed in the design. Finite Element Analyses (FEAs) for the electrostatic and the structural configuration is carried out to validate the design of the High Voltage Bushing (HVB). Several iterations and optimizations of the stress shields are carried out to meet electrostatic criteria, especially at the triple point (the ceramic, metal and vacuum joint), which is critical for good voltage holding. Structural analyses is carried out to assess the stress distribution in the fiber reinforced plastic insulator, the alumina insulator and the integrated HVB for different load cases like operational orientation (horizontal), normal operation and accidental case. Design is further validated for seismic conditions for Seismic Loading-2 (SL-2).

  16. Design optimization of the 100 kV HV bushing for ITER-DNB

    International Nuclear Information System (INIS)

    Shah, Sejal; Rajesh, S.; Srusti, B.; Bandyopadhyay, M.; Rotti, C.; Singh, M.J.; Roopesh, G.; Chakraborty, A.K.; Schunke, B.; Hemsworth, R.; Chareyre, J.

    2011-01-01

    The 100 kV bushing of the Diagnostic Neutral Beam (DNB) injector is a cylindrical feedthrough which forms the interface between the gas insulated transmission line and the torus primary vacuum and provides all necessary services to the beam source. All conventions for safety, voltage holding requirement, vacuum compatibility and the choice of materials have been addressed in the design. Finite Element Analyses (FEAs) for the electrostatic and the structural configuration is carried out to validate the design of the High Voltage Bushing (HVB). Several iterations and optimizations of the stress shields are carried out to meet electrostatic criteria, especially at the triple point (the ceramic, metal and vacuum joint), which is critical for good voltage holding. Structural analyses is carried out to assess the stress distribution in the fiber reinforced plastic insulator, the alumina insulator and the integrated HVB for different load cases like operational orientation (horizontal), normal operation and accidental case. Design is further validated for seismic conditions for Seismic Loading-2 (SL-2).

  17. MATL : Canada's first merchant power transmission interconnection : experiences and future outlook

    International Nuclear Information System (INIS)

    Wilson, L.

    2006-01-01

    The current status of the Montana Alberta Tie Ltd. (MATL) merchant transmission project was outlined with reference to the business concept, the advantages of the project and market opportunities. Some of the challenges facing the project were discussed along with lessons learned and accomplishments thus far. MATL is preparing to construct a privately funded transmission line between Lethbridge, Alberta and Great Falls, Montana. The project represents the first direct power transmission inter-connection between Montana and Alberta. The 346 km, 230 kV AC transmission line with phase shifting transformer and 300 MW transfer capacity will be a synchronous interconnection and will improve the reliability of the entire electric systems in both Montana and Alberta. The benefits of the interconnected power system include increased reliability and stability of the existing power grids; better import/export capabilities; more competition and options in the marketplace; greater flexibility in scheduling generator maintenance; and, optimal allocation of generation resources. tabs., figs

  18. A continuous acceleration tube of ions under 200 KV; Un tube d'acceleration continue d'ions sous 200 KV

    Energy Technology Data Exchange (ETDEWEB)

    Mongodin, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1954-07-01

    The realization of an Van de Graaff accelerator required, for the preliminary studies, the construction of a small proton accelerator, functioning at 200 kV in order to resolve some parasitic effects inherent to the accelerators tubes. The aim of this report is to describe the different organs of the accelerator tube, to explain the operating system and to encode their characteristics. The report first presents the ion source and the beam buncher permitting to inject in the accelerator tube particles of about 9 kV and very batched in a thin beam of circular section. Then the study explain the tube characteristics considered like optic system. A method to obtain precise calculation of particle trajectories is exposed. Aberrations of the system were discussed and balance of the currents on all electrodes inside the tube for different regimes of working were provided. The influence of the residual pressure in the tube were explained. The report finally ends on a part of the fundamental problem of the straining occurring inside the tubes accelerators under high tension. (M.B.) [French] La realisation d n accelerateur du type Van de Graaff a necessite, entre autres etudes preliminaires, la construction d'un petit accelerateur de protons, fonctionnant sous 200 kV afin d'eclaircir certains effets parasites propres aux tubes accelerateurs. L'objet de ce rapport est de decrire les differents organes du tube accelerateur, d'en expliquer le fonctionnement et de chiffrer leurs caracteristiques. Le memoire presente d'abord la source d'ions et le canon permettant d'injecter dans le tube accelerateur des particules de 9 kV environ et bien groupees dans un faisceau fin de section circulaire. Puis il passe a l'etude du tube considere comme systeme optique. Une methode utilisee pour le calcul precis des trajectoires des particules y est exposee. Il aborde le probleme des aberrations de ce systeme et fournit par la suite le bilan des courants sur toutes les electrodes a l

  19. Analytical Model for High Impedance Fault Analysis in Transmission Lines

    Directory of Open Access Journals (Sweden)

    S. Maximov

    2014-01-01

    Full Text Available A high impedance fault (HIF normally occurs when an overhead power line physically breaks and falls to the ground. Such faults are difficult to detect because they often draw small currents which cannot be detected by conventional overcurrent protection. Furthermore, an electric arc accompanies HIFs, resulting in fire hazard, damage to electrical devices, and risk with human life. This paper presents an analytical model to analyze the interaction between the electric arc associated to HIFs and a transmission line. A joint analytical solution to the wave equation for a transmission line and a nonlinear equation for the arc model is presented. The analytical model is validated by means of comparisons between measured and calculated results. Several cases of study are presented which support the foundation and accuracy of the proposed model.

  20. Electric and magnetic field reduction by alternative transmission line options

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, J.R. (Power Technologies, Inc., Schenectady, NY (United States)); Dale, S.J. (Oak Ridge National Lab., TN (United States)); Klein, K.W. (Energetics, Inc., Columbia, MD (United States))

    1991-01-01

    Ground level electric, and more recently magnetic, fields from overhead power transmission lines are increasingly important considerations in right of way specification, with states setting or planning to set edge of right of way limits. Research has been conducted in high phase order power transmission wherein six of twelve phases are used to transmit power in less physical space and with reduced electrical environmental effects than conventional designs. The first magnetic field testing, as reported in this paper, has verified predictive methods for determination of magnetic fields from high phase order lines. Based on these analytical methods, field profiles have been determined for lines of different phase order of comparable power capacity. Potential advantages of high phase order as a means of field mitigation are discussed. 10 refs., 12 figs., 3 tabs.

  1. 77 FR 514 - Notice of Availability of the Record of Decision for the North Steens 230 Kilovolt Transmission...

    Science.gov (United States)

    2012-01-05

    ... subsidiary of Columbia Energy Partners, LLC, filed right-of-way (ROW) applications for ROWs with the BLM and... transmission system near Diamond Junction, Oregon. The ROD approves the BLM-preferred Alternative, now the... Project substation, south of Diamond, Oregon and connect to Harney Electric Cooperative's existing 115-kV...

  2. Designing concept on lightning protection of overhead power distribution line

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, Shigeru [Central Research Institute of Electric Power Industry, Kanagawa-ken (Japan)], E-mail: yokoyama@criepi.denken.or.jp

    2007-07-01

    The principle is shown for lightning protection of power distribution lines taking the effects of surge arresters, overhead ground wires and their combined use into consideration. Moreover an outline of a rational design method targeting direct lightning hits, induced over voltages and back flow currents from high structures. (author)

  3. Communication overhead on the Intel iPSC-860 hypercube

    Science.gov (United States)

    Bokhari, Shahid H.

    1990-01-01

    Experiments were conducted on the Intel iPSC-860 hypercube in order to evaluate the overhead of interprocessor communication. It is demonstrated that: (1) contrary to popular belief, the distance between two communicating processors has a significant impact on communication time, (2) edge contention can increase communication time by a factor of more than 7, and (3) node contention has no measurable impact.

  4. The voltage-gated potassium channel subunit, Kv1.3, is expressed in epithelia

    DEFF Research Database (Denmark)

    Grunnet, Morten; Rasmussen, Hanne B; Hay-Schmidt, Anders

    2003-01-01

    The Shaker-type voltage-gated potassium channel, Kv1.3, is believed to be restricted in distribution to lymphocytes and neurons. In lymphocytes, this channel has gained intense attention since it has been proven that inhibition of Kv1.3 channels compromise T lymphocyte activation. To investigate...

  5. Development of a 300-kV Marx generator and its application to drive ...

    Indian Academy of Sciences (India)

    Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, ... anode gap of 7·5 mm, an REB having beam voltage 160 kV and duration 150 ns ... lowest stage has a triggered SG which is closed by a 6 kV pulse obtained with the ...

  6. Joint HVAC Transmission EMF Environmental Study : Final Report on Experiment 1.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration; Oregon Regional Primate Research Center

    1992-05-01

    This document describes the rationale, procedures, and results of a carefully controlled study conducted to establish whether chronic exposure of female (ewe) Suffolk lambs to the environment of a 500-kV 60-Hz transmission line would affect various characteristics of growth, endocrine function, and reproductive development. This experiment used identical housing and management schemes for control and line-exposed ewes, thus minimizing these factors as contributors to between-group experimental error. Further, throughout the 10-month duration of this study, changes in electric and magnetic fields, audible noise, and weather conditions were monitored continuously by a computerized system. Such measurements provided the opportunity to identify any relationship between environmental factors and biological responses. Because of reports in the literature that electric and magnetic fields alter concentrations of melatonin in laboratory animals, the primary objective of this study was to ascertain whether a similar effect occurs in lambs exposed to a 500-kV a-c line in a natural setting. In addition, onset of puberty, changes in body weight, wool growth, and behavior were monitored. To determine whether the environment of a 500-kV line caused stress in the study animals, serum levels of cortisol were measured. The study was conducted at Bonneville Power Administration`s Ostrander Substation near Estacada, Oregon.

  7. High power cable with internal water cooling 400 kV

    Energy Technology Data Exchange (ETDEWEB)

    Rasquin, W; Harjes, B

    1982-08-01

    The project was planned for a duration of 4 years. Afterwards it has been extended over 6 years and finally stopped after 3 1/2 years. Therefore, of course results of field tests with an internally cooled 400 kV cable are not available. Nevertheless, this conductor cooled high power cable has been developed to such an extend, that this manufactured cable could withstand type tests according to IEC/VDE recommendations. Even by missing field tests it is obvious that a high power cable for 400 kV is available.

  8. Trafficking of Kv2.1 Channels to the Axon Initial Segment by a Novel Nonconventional Secretory Pathway

    DEFF Research Database (Denmark)

    Jensen, Camilla Stampe; Watanabe, Shoji; Stas, Jeroen Ingrid

    2017-01-01

    the localization of Kv2.1 in these two different membrane compartments in cultured rat hippocampal neurons of mixed sex. Our data uncover a unique ability of Kv2.1 channels to use two molecularly distinct trafficking pathways to accomplish this. Somatodendritic Kv2.1 channels are targeted by the conventional...... secretory pathway, whereas axonal Kv2.1 channels are targeted by a nonconventional trafficking pathway independent of the Golgi apparatus. We further identified a new AIS trafficking motif in the C-terminus of Kv2.1, and show that putative phosphorylation sites in this region are critical for the restricted.......SIGNIFICANCE STATEMENT Our study uncovered a novel mechanism that targets the Kv2.1 voltage-gated potassium channel to two distinct trafficking pathways and two distinct subcellular destinations: the somatodendritic plasma membrane and that of the axon initial segment. We also identified a distinct motif, including...

  9. Design and Control of a 13.2 kV/10 kVA Single-Phase Solid-State-Transformer with 1.7 kV SiC Devices

    Directory of Open Access Journals (Sweden)

    Jeong-Woo Lim

    2018-01-01

    Full Text Available This paper describes the power stage design, control, and performance evaluation of a 13.2 kV/10 kVA solid-state-transformer (SST for a power distribution system. The proposed SST consists of 10 modules where each individual module contains a unidirectional three-level power factor correction (PFC converter for the active-front-end (AFE stage and an LLC resonant converter for the isolated DC-DC stage. The operating principles of the converters are analyzed and the modulation and the control schemes for the entire module are described in detail. The DC-link voltage imbalance is also less than other SST topologies due to the low number of uncontrollable switching states. In order to simplify the control of the power stage, a modulation strategy for the AFE stage is proposed, and the modulation frequency of the LLC converter is also fixed. In addition, a compensation algorithm is suggested to eliminate the current measurement offset in the AFE stage. The proposed SST achieves the unity power factor at the input AC current regardless of the reactive or nonlinear load and a low voltage regulation at the AC output. In order to verify the effectiveness of the SST, the 13.2 kV/10 kV SST prototype is built and tested. Both the simulation and the experimental results under actual 13.2 kV line show the excellent performance of the proposed SST scheme.

  10. The schizophrenia-associated Kv11.1-3.1 isoform results in reduced current accumulation during repetitive brief depolarizations.

    Directory of Open Access Journals (Sweden)

    Juliane Heide

    Full Text Available Recent genome wide association studies identified a brain and primate specific isoform of a voltage-gated potassium channel, referred to as Kv11.1-3.1, which is significantly associated with schizophrenia. The 3.1 isoform replaces the first 102 amino acids of the most abundant isoform (referred to as Kv11.1-1A with six unique amino acids. Here we show that the Kv11.1-3.1 isoform has faster rates of channel deactivation but a slowing of the rates of inactivation compared to the Kv11.1-1A isoform. The Kv11.1-3.1 isoform also has a significant depolarizing shift in the voltage-dependence of steady-state inactivation. The consequence of the altered gating kinetics is that there is lower current accumulation for Kv11.1-3.1 expressing cells during repetitive action potential firing compared to Kv11.1-1A expressing cells, which in turn will result in longer lasting trains of action potentials. Increased expression of Kv11.1-3.1 channels in the brain of schizophrenia patients might therefore contribute to disorganized neuronal firing.

  11. Parameter design and performance simulation of a 10 kV voltage compensation type active superconducting fault current limiter

    International Nuclear Information System (INIS)

    Chen, L.; Tang, Y.J.; Song, M.; Shi, J.; Ren, L.

    2013-01-01

    Highlights: •For a practical 10 kV system, the 10 kV active SFCL’s basic parameters are designed. •Under different fault conditions, the 10 kV active SFCL’s performances are simulated. •The designed 10 kV active SFCL’s engineering feasibility is discussed preliminarily. -- Abstract: Since the introduction of superconducting fault current limiter (SFCL) into electrical distribution system may be a good choice with economy and practicability, the parameter design and current-limiting characteristics of a 10 kV voltage compensation type active SFCL are studied in this paper. Firstly, the SFCL’s circuit structure and operation principle are presented. Then, taking a practical 10 kV distribution system as its application object, the SFCL’s basic parameters are designed to meet the system requirements. Further, using MATLAB, the detailed current-limiting performances of the 10 kV active SFCL are simulated under different fault conditions. The simulation results show that the active SFCL can deal well with the faults, and the parameter design’s suitability can be testified. At the end, in view of the engineering feasibility of the 10 kV active SFCL, some preliminary discussions are carried out

  12. Optimization of the box-girder of overhead crane with constrained ...

    African Journals Online (AJOL)

    Keywords: Overhead crane - Box-girder - New bat algorithm - level of comparison - Higher strength steel. Optimisation de poutre caisson de pont roulant avec un nouvel algorithme de chauve souris sous contrainte. Une conception optimale pour un poids minimal de la poutre principale d'un pont roulant peut réduire ...

  13. KCNE3 is an inhibitory subunit of the Kv4.3 potassium channel

    DEFF Research Database (Denmark)

    Lundby, Alicia; Olesen, Søren-Peter

    2006-01-01

    The mammalian Kv4.3 potassium channel is a fast activating and inactivating K+ channel widely distributed in mammalian tissues. Kv4.3 is the major component of various physiologically important currents ranging from A-type currents in the CNS to the transient outward potassium conductance in the ...

  14. An Evaluation of Media-Oriented Rate Selection Algorithm for Multimedia Transmission in MANETs

    Directory of Open Access Journals (Sweden)

    Guionnet Thomas

    2005-01-01

    Full Text Available We focus on the optimization of real-time multimedia transmission over 802.11-based ad hoc networks. In particular, we propose a simple and efficient cross-layer mechanism that considers both the channel conditions and characteristics of the media for dynamically selecting the transmission mode. This mechanism called media-oriented rate selection algorithm (MORSA targets loss-tolerant applications such as VoD that do not require full reliable transmission. We provide an evaluation of this mechanism for MANETs using simulations with NS and analyze the video quality obtained with a fine-grain scalable video encoder based on a motion-compensated spatiotemporal wavelet transform. Our results show that MORSA achieves up to 4 Mbps increase in throughput and that the routing overhead decreases significantly. Transmission of a sample video flow over an 802.11a wireless channel has been evaluated with MORSA. Important improvement is observed in throughput, latency, and jitter while keeping a good level of video quality.

  15. Structural Design of Two-Cylinder Single Overhead Camshaft

    Science.gov (United States)

    Zhao, Yuxia; Zhang, Kangsheng; Di, Jiejian

    2018-01-01

    Due to the higher performance demand, the camshaft is the key driving part in the engine. Because it is eccentric circular section part, it is very difficult to design and manufacture this kind of axial parts. Take two-cylinder single overhead camshaft for an example, the entire process of camshaft design is analyzed. The practice has proved that the method has simple, flexible and efficient advantages, and it can greatly shorten the design of artificial computing time.

  16. 75 FR 44288 - Overhead and Gantry Cranes; Extension of the Office of Management and Budget's (OMB) Approval of...

    Science.gov (United States)

    2010-07-28

    ...] Overhead and Gantry Cranes; Extension of the Office of Management and Budget's (OMB) Approval of... requirements specified in the Standard on Overhead and Gantry Cranes (29 CFR 1910.179). DATES: Comments must be... requirements for: Marking the rated load of cranes; preparing certification records to verify the inspection of...

  17. 40-kV, 25-ms neutral-beam power supply for TMX

    International Nuclear Information System (INIS)

    Leavitt, G.A.

    1977-01-01

    Modifications are described to upgrade the neutral-beam power supply for the TMX from 40 kV, 10 ms to 40 kV, 25 ms. The redesign of the accel and suppressor power supplies to achieve separation of the high-voltage and control sections, operation of the arc pulse lines in series, operation of the arc pulse lines in a noisy environment with SCR trigger and crowbar, and modifications to the electrolytic storage banks are discussed

  18. Uptake and Accumulation of Pharmaceuticals in Lettuce Under Surface and Overhead Irrigations

    Science.gov (United States)

    Bhalsod, G.; Chuang, Y. H.; Jeon, S.; Gui, W.; Li, H.; Guber, A.; Zhang, W.

    2015-12-01

    Pharmaceuticals and personal care products are being widely detected in wastewater and surface waters. As fresh water becomes scarcer, interests in using reclaimed water for crop irrigation is intensified. Since reclaimed waters often carry trace levels of pharmaceuticals, accumulation of pharmaceuticals in food crops could increase the risk of human exposure. This study aims to investigate uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead and surface irrigations). Lettuce was irrigated with water spiked with 11 commonly used pharmaceuticals (acetaminophen, caffeine, carbamazepine, sulfadiazine, sulfamethoxazole, carbadox, trimethoprim, lincomycin hydrochloride, oxytetracycline hydrochloride, monensin sodium, and tylosin). Weekly sampling of lettuce roots, shoots, and soils were continued for 5 weeks, and the samples were freeze dried, extracted for pharmaceuticals and analyzed by LC-MS/MS. Preliminary results indicate that higher concentrations of pharmaceuticals were found in overhead irrigated lettuce compared to surface irrigated lettuce. For carbamezapine, sulfadiazine, trimethoprim, oxytetracycline, and monensin sodium, their concentrations generally increased in lettuce shoots in the overhead treatment over time. However, acetaminophen was found at higher concentrations in both shoots and roots, indicating that acetaminophen can be easily transported in the plant system. This study provides insight on developing better strategies for using reclaimed water for crop irrigations, while minimizing the potential risks of pharmaceutical contamination of vegetables.

  19. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-60) - Rocky Reach - Maple Valley No. 1

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Mark A. [Bonneville Power Administration (BPA), Portland, OR (United States)

    2002-04-15

    Vegetation Management along the Rocky Reach – Maple Valley No. 1 Transmission Line ROW from structure 110/1 to the Maple Valley Substation. The transmission line is a 500 kV line. BPA proposes to clear targeted vegetation along access roads and around tower structures that may impede the operation and maintenance of the subject transmission line. BPA plans to conduct vegetation management along existing access road and around structure landings for the purpose of maintaining access to structures site. All work will be in accordance with the National Electrical Safety Code and BPA standards.

  20. Thyristors for dc transmission

    Energy Technology Data Exchange (ETDEWEB)

    1966-05-06

    As a first stage towards determining the feasibility of applying thyristors to hvdc converter terminals, the Westinghouse Electric Corporation has built a converter laboratory capable of testing thyristors under conditions similar to those which would have to be met in a 200 kV dc system. The equipment has been designed to test a 5 kV 600 A group of thyrisotrs, elevated 200 kV above earth. This rating has been chosen so that there would be a sufficient number of thyristors in series to enable the gating and voltage division characteristics to be investigated and at the same time the group could be operated at a potential equivalent to a complete 200 kV dc bridge.

  1. Solid Modeling and Finite Element Analysis of an Overhead Crane Bridge

    Directory of Open Access Journals (Sweden)

    C. Alkin

    2005-01-01

    Full Text Available The design of an overhead crane bridge with a double box girder has been investigated and a case study of a crane with 35 ton capacity and 13 m span length has been conducted. In the initial phase of the case study, conventional design calculations proposed by F. E. M. Rules and DIN standards were performed to verify the stress and deflection levels. The crane design was modeled using both solids and surfaces. Finite element meshes with 4-node tetrahedral and 4-node quadrilateral shell elements were generated from the solid and shell models, respectively. After a comparison of the finite element analyses, the conventional calculations and performance of the existing crane, the analysis with quadratic shell elements was found to give the most realistic results. As a result of this study, a design optimization method for an overhead crane is proposed. 

  2. A compact 100 kV high voltage glycol capacitor.

    Science.gov (United States)

    Wang, Langning; Liu, Jinliang; Feng, Jiahuai

    2015-01-01

    A high voltage capacitor is described in this paper. The capacitor uses glycerol as energy storage medium, has a large capacitance close to 1 nF, can hold off voltages of up to 100 kV for μs charging time. Allowing for low inductance, the capacitor electrode is designed as coaxial structure, which is different from the common structure of the ceramic capacitor. With a steady capacitance at different frequencies and a high hold-off voltage of up to 100 kV, the glycol capacitor design provides a potential substitute for the ceramic capacitors in pulse-forming network modulator to generate high voltage pulses with a width longer than 100 ns.

  3. 80 kV electrostatic wire septum for AmPS

    International Nuclear Information System (INIS)

    Linden, A. van der; Bijleveld, J.H.M.; Rookhuizen, H.B.; Bruinsma, P.J.T.; Heine, E.; Lassing, P.; Prins, E.

    1992-01-01

    The Amsterdam Pulse Stretcher (AmPS) ring aims at a 100% duty cycle operation by means of slow extraction of injected electron beam pulses of 2.1 μs. In the extraction process of the AmPS, the extracted beam is intercepted from the circulating beam by the 1 m long electrostatic wire septum. For a bending angle of 4.4 mrad the maximum anode voltage is 80 kV. Care has been given to the electric field distribution at the entrance and exit of the septum and to the insulators, required to support the anode. Prototype tests have been successful up to an anode voltage of 120 kV. (R.P.) 9 refs.; 5 figs

  4. Pharmacological dissection of K(v)7.1 channels in systemic and pulmonary arteries

    DEFF Research Database (Denmark)

    Chadha, Preet S; Zunke, Friederike; Davis, Alison J

    2012-01-01

    The aim of this study was to characterize the functional impact of KCNQ1-encoded voltage-dependent potassium channels (K(v)7.1) in the vasculature.......The aim of this study was to characterize the functional impact of KCNQ1-encoded voltage-dependent potassium channels (K(v)7.1) in the vasculature....

  5. harmonic load modeling: a case study of 33 kv abuja steel mill feeder

    African Journals Online (AJOL)

    HOD

    techniques are adopted. This paper studied the harmonic orders of the 33 kV Abuja Steel Feeder modeled as a ... (ETAP) software package was deployed to perform Discrete Fast Transform (DFT) while the input ... and documented in research and development articles ... network with 33kV Abuja Steel feeder as case study.

  6. Experimental Investigation on Propagation Characteristics of PD Radiated UHF Signal in Actual 252 kV GIS

    Directory of Open Access Journals (Sweden)

    Tianhui Li

    2017-07-01

    Full Text Available For partial discharge (PD diagnostics in gas insulated switchgears (GISs based on the ultra-high-frequency (UHF method, it is essential to study the attenuation characteristics of UHF signals so as to improve the application of the UHF technique. Currently, the performance of UHF has not been adequately considered in most experimental research, while the constructive conclusions about the installation and position of UHF sensors are relatively rare. In this research, by using a previously-designed broadband sensor, the output signal is detected and analyzed experimentally in a 252 kV GIS with L-shaped structure and disconnecting switch. Since the relative position of the sensor and the defect is usually fixed by prior research, three circumferential angle positions of the defect in cross section are performed. The results are studied by time, statistics and frequency analyses. This identifies that the discontinuity conductor of DS will lead to a rise of both the peak to peak value (Vpp and the transmission rate of the UHF signal. Then, the frequency analysis indicates that the reason for the distinction of signal amplitude and transmission rate is that the mode components of the PD signal are distinctively affected by the special structure of GIS. Finally, the optimal circumferential angle position of the UHF Sensor is given based on the comparison of transmission rates.

  7. The Transmission Line for the SPIDER experiment

    International Nuclear Information System (INIS)

    Boldrin, Marco; De Lorenzi, Antonio; Recchia, Mauro; Toigo, Vanni; Bonicelli, Tullio; Simon, Muriel

    2011-01-01

    The 100 keV Ion Source Test facility - Source for the Production of Ions of Deuterium Extracted from RF plasma (SPIDER) - is aimed to test the full scale prototype of the Ion Source for the ITER 1 MeV Neutral Beam Injector (NBI). The SPIDER facility requires the construction of a High Voltage Deck (HVD) and of a High Voltage Transmission Line (TL) respectively to host the Ion Source Power Supplies system polarized at 100 kV and to carry the power and signal conductors to the beam accelerator. In already existing NBI systems with beam energy above 100 keV, the TL is realized with the SF 6 Gas Insulated Line technology. In the SPIDER TL case, the presence of a large inner conductor (half meter diameter), would make the pressurized TL a complex and costly component; therefore a free air insulated solution has been proposed. The paper focuses on the design of this TL, which has to host inside the complex high potential (100 kV) inner electrode a number of power and measuring conductors and has to minimize the Electro Magnetic Interferences (EMI) produced by the frequent grids breakdowns. Finite Element (FE) analyses have been performed to verify the configuration from the electrostatic point of view, to evaluate EMI screening effectiveness and to assess the impact of the relatively high thermal dissipation of power conductors located inside the high potential electrode. Moreover, an experimental test campaign has been carried out on a TL mockup to validate the TL electrostatic configuration under DC voltage. Finally, the paper reports on the status of procurement activities for the Transmission Line.

  8. Serum Starvation-Induced Voltage-Gated Potassium Channel Kv7.5 Expression and Its Regulation by Sp1 in Canine Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Bo Hyung Lee

    2014-01-01

    Full Text Available The KCNQ gene family, whose members encode Kv7 channels, belongs to the voltage-gated potassium (Kv channel group. The roles of this gene family have been widely investigated in nerve and muscle cells. In the present study, we investigated several characteristics of Kv7.5, which is strongly expressed in the canine osteosarcoma cell line, CCL-183. Serum starvation upregulated Kv7.5 expression, and the Kv7 channel opener, flupirtine, attenuated cell proliferation by arresting cells in the G0/G1 phase. We also showed that Kv7.5 knockdown helps CCL-183 cells to proliferate. In an effort to find an endogenous regulator of Kv7.5, we used mithramycin A to reduce the level of the transcription factor Sp1, and it strongly inhibited the induction of Kv7.5 in CCL-183 cells. These results suggest that the activation of Kv7.5 by flupirtine may exert an anti-proliferative effect in canine osteosarcoma. Therefore, Kv7.5 is a possible molecular target for canine osteosarcoma therapy.

  9. Evaluation of variation of voltage (kV) absorbed dose in chest CT scans

    International Nuclear Information System (INIS)

    Mendonca, Bruna G.A.; Mourao, Arnaldo P.

    2013-01-01

    Computed tomography (CT) is one of the most important diagnostic techniques images today. The increasing utilization of CT implies a significant increase of population exposure to ionizing radiation. Optimization of practice aims to reduce doses to patients because the image quality is directly related to the diagnosis. You can decrease the amount of dose to the patient, and maintain the quality of the image. There are several parameters that can be manipulated in a CT scan and these parameters can be used to reduce the energy deposited in the patient. Based on this, we analyzed the variation of dose deposited in the lungs, breasts and thyroid, by varying the supply voltage of the tube. Scans of the thorax were performed following the protocol of routine chest with constant and variable current for the same applied voltage. Moreover, a female phantom was used and thermoluminescent dosimeters (TLD-100), model bat, were used to record the specific organ doses. Scans were performed on a GE CT scanner, model 64 Discovery channels. Higher doses were recorded for the voltage of 120 kV with 200 mAs in the lungs (22.46 mGy) and thyroid (32.22 mGy). For scans with automatic mAs, variable between 100 and 440, this same tension contributed to the higher doses. The best examination in terms of the dose that was used with automatic 80 kV mAs, whose lungs and thyroid received lower dose. For the best breast exam was 100 kV. Since the increase in the 80 kV to 100 kV no impact so much the dose deposited in the lungs, it can be concluded that lowering the applied voltage to 100 kV resulted in a reduction in the dose absorbed by the patient. These results can contribute to optimizing scans of the chest computed tomography

  10. Expression and function of Kv1.1 potassium channels in human atria from patients with atrial fibrillation.

    Science.gov (United States)

    Glasscock, Edward; Voigt, Niels; McCauley, Mark D; Sun, Qiang; Li, Na; Chiang, David Y; Zhou, Xiao-Bo; Molina, Cristina E; Thomas, Dierk; Schmidt, Constanze; Skapura, Darlene G; Noebels, Jeffrey L; Dobrev, Dobromir; Wehrens, Xander H T

    2015-09-01

    Voltage-gated Kv1.1 channels encoded by the Kcna1 gene are traditionally regarded as being neural-specific with no known expression or intrinsic functional role in the heart. However, recent studies in mice reveal low-level Kv1.1 expression in heart and cardiac abnormalities associated with Kv1.1-deficiency suggesting that the channel may have a previously unrecognized cardiac role. Therefore, this study tests the hypothesis that Kv1.1 channels are associated with arrhythmogenesis and contribute to intrinsic cardiac function. In intra-atrial burst pacing experiments, Kcna1-null mice exhibited increased susceptibility to atrial fibrillation (AF). The atria of Kcna1-null mice showed minimal Kv1 family ion channel remodeling and fibrosis as measured by qRT-PCR and Masson's trichrome histology, respectively. Using RT-PCR, immunocytochemistry, and immunoblotting, KCNA1 mRNA and protein were detected in isolated mouse cardiomyocytes and human atria for the first time. Patients with chronic AF (cAF) showed no changes in KCNA1 mRNA levels relative to controls; however, they exhibited increases in atrial Kv1.1 protein levels, not seen in paroxysmal AF patients. Patch-clamp recordings of isolated human atrial myocytes revealed significant dendrotoxin-K (DTX-K)-sensitive outward current components that were significantly increased in cAF patients, reflecting a contribution by Kv1.1 channels. The concomitant increases in Kv1.1 protein and DTX-K-sensitive currents in atria of cAF patients suggest that the channel contributes to the pathological mechanisms of persistent AF. These findings provide evidence of an intrinsic cardiac role of Kv1.1 channels and indicate that they may contribute to atrial repolarization and AF susceptibility.

  11. Radiation dose reduction sinogram affirmed iterative reconstruction and automatic tube voltage modulation(CARE kV) in abdominal CT

    International Nuclear Information System (INIS)

    Shin, Hyun Joo; Chung, Yong Eun; Lee, Young Han; Choi, Jin Young; Park, Mi Suk; Kim, Myeong Jin; Kim, Ki Whang

    2013-01-01

    To evaluate the feasibility of sinogram-affirmed iterative reconstruction (SAFIRE) and automated kV modulation (CARE kV) in reducing radiation dose without increasing image noise for abdominal CT examination. This retrospective study included 77 patients who received CT imaging with an application of CARE kV with or without SAFIRE and who had comparable previous CT images obtained without CARE kV or SAFIRE, using the standard dose (i.e., reference mAs of 240) on an identical CT scanner and reconstructed with filtered back projection (FBP) within 1 year. Patients were divided into two groups: group A (33 patients, CT scanned with CARE kV); and group B (44 patients, scanned after reducing the reference mAs from 240 to 170 and applying both CARE kV and SAFIRE). CT number, image noise for four organs and radiation dose were compared among the two groups. Image noise increased after CARE kV application (p < 0.001) and significantly decreased as SAFIRE strength increased (p < 0.001). Image noise with reduced-mAs scan (170 mAs) in group B became similar to that of standard-dose FBP images after applying CARE kV and SAFIRE strengths of 3 or 4 when measured in the aorta, liver or muscle (p ≥ 0.108). Effective doses decreased by 19.4% and 41.3% for groups A and B, respectively (all, p < 0.001) after application of CARE kV with or without SAFIRE. Combining CARE kV, reduction of mAs from 240 to 170 mAs and noise reduction by applying SAFIRE strength 3 or 4 reduced the radiation dose by 41.3% without increasing image noise compared with the standard-dose FBP images.

  12. 30 CFR 77.203 - Use of material or equipment overhead; safeguards.

    Science.gov (United States)

    2010-07-01

    ...; safeguards. 77.203 Section 77.203 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS...; safeguards. Where overhead repairs are being made at surface installations and equipment or material is taken...

  13. Improvement of the 400 kV linac electron source of AmPS

    International Nuclear Information System (INIS)

    Kroes, F.B.; Beuzekom, M.G. van; Dobbe, N.J.; Es, J.T. van; Jansweijer, P.P.M.; Kruijer, A.H.; Luigjes, G.; Sluijk, T.G.B.

    1992-01-01

    The installation of the 900 MeV Amsterdam Pulse Stretcher is nearly completed and its commissioning will start Spring 1992. The existing linac MEA will inject electrons in the AmPS ring. The linacs peak current will be increased from 20 to 80 mA. This requires modification of the 400 kV low emittance gun which now will deliver a peak current of maximum 400 mA instead of 100 mA at a pulse width of 2.1 μsec. The fourfold increase of the peakcurrent is obtained by doubling both the gun perveance (new gun part) and the pulsed extractor voltage. After chopping and pre-bunching more than 80 mA will be available for acceleration in MEA. To obtain optimum beam quality over this increased current range the hot deck electronics, operating at -400 kV, has been exchanged by a state of the art fast high voltage FET switching supply. The increased space charge forces in the beam require stronger electro-static focusing in the first electrostatic gap to define the beam diameter at the gun exit. This is accomplished with a 25 kV controlled power supply. A build in microprocessor, coupled to the local computer by optical fibers, is used to monitor and control the gun parameters. The 5kV gun extractor voltage pulse shape can be monitored by means of an analog fibre transducer with build in calibration. Finally, in order to improve the energy stability of the accelerated electrons a serial electron-tube stabilizer was added to the 400 kV DC power supply. A supply stability of 2. 10 -5 has been achieved. (author). 4 refs.; 6 figs

  14. Field Demonstration of a 24-kV Superconducting Cable at Detroit Edison

    International Nuclear Information System (INIS)

    Kelley, Nathan; Corsaro, Pietro

    2004-01-01

    Customer acceptance of high temperature superconducting (HTS) cable technology requires a substantial field demonstration illustrating both the system's technical capabilities and its suitability for installation and operation within the utility environment. In this project, the world's first underground installation of an HTS cable using existing ductwork, a 120 meter demonstration cable circuit was designed and installed between the 24 kV bus distribution bus and a 120 kV-24 kV transformer at Detroit Edison's Frisbie substation. The system incorporated cables, accessories, a refrigeration system, and control instrumentation. Although the system was never put in operation because of problems with leaks in the cryostat, the project significantly advanced the state-of-the-art in the design and implementation of Warm Dielectric cable systems in substation applications. Lessons learned in this project are already being incorporated in several ongoing demonstration projects

  15. Early-onset epileptic encephalopathy caused by a reduced sensitivity of Kv7.2 potassium channels to phosphatidylinositol 4,5-bisphosphate.

    Science.gov (United States)

    Soldovieri, Maria Virginia; Ambrosino, Paolo; Mosca, Ilaria; De Maria, Michela; Moretto, Edoardo; Miceli, Francesco; Alaimo, Alessandro; Iraci, Nunzio; Manocchio, Laura; Medoro, Alessandro; Passafaro, Maria; Taglialatela, Maurizio

    2016-12-01

    Kv7.2 and Kv7.3 subunits underlie the M-current, a neuronal K + current characterized by an absolute functional requirement for phosphatidylinositol 4,5-bisphosphate (PIP 2 ). Kv7.2 gene mutations cause early-onset neonatal seizures with heterogeneous clinical outcomes, ranging from self-limiting benign familial neonatal seizures to severe early-onset epileptic encephalopathy (Kv7.2-EE). In this study, the biochemical and functional consequences prompted by a recurrent variant (R325G) found independently in four individuals with severe forms of neonatal-onset EE have been investigated. Upon heterologous expression, homomeric Kv7.2 R325G channels were non-functional, despite biotin-capture in Western blots revealed normal plasma membrane subunit expression. Mutant subunits exerted dominant-negative effects when incorporated into heteromeric channels with Kv7.2 and/or Kv7.3 subunits. Increasing cellular PIP 2 levels by co-expression of type 1γ PI(4)P5-kinase (PIP5K) partially recovered homomeric Kv7.2 R325G channel function. Currents carried by heteromeric channels incorporating Kv7.2 R325G subunits were more readily inhibited than wild-type channels upon activation of a voltage-sensitive phosphatase (VSP), and recovered more slowly upon VSP switch-off. These results reveal for the first time that a mutation-induced decrease in current sensitivity to PIP 2 is the primary molecular defect responsible for Kv7.2-EE in individuals carrying the R325G variant, further expanding the range of pathogenetic mechanisms exploitable for personalized treatment of Kv7.2-related epilepsies.

  16. Remodeling of Kv1.5 channel in right atria from Han Chinese patients with atrial fibrillation.

    Science.gov (United States)

    Ou, Xian-hong; Li, Miao-ling; Liu, Rui; Fan, Xin-rong; Mao, Liang; Fan, Xue-hui; Yang, Yan; Zeng, Xiao-rong

    2015-04-28

    The incidence of atrial fibrillation (AF) in rheumatic heart diseases (RHD) is very high and increases with age. Occurrence and maintenance of AF are very complicated process accompanied by many different mechanisms. Ion-channel remodeling, including the voltage-gated potassium channel Kv1.5, plays an important role in the pathophysiology of AF. However, the changes of Kv1.5 channel expression in Han Chinese patients with RHD and AF remain poorly understood. The aim of the present study was to investigate whether the Kv1.5 channels of the right atria may be altered with RHD, age, and sex to contribute to AF. Right atrial appendages were obtained from 20 patients with normal cardiac functions who had undergone surgery, and 26 patients with AF. Subjects were picked from 4 groups: adult and aged patients in normal sinus rhythm (SR) and AF. Patients were divided into non-RHD and RHD groups or men and women groups in normal SR and AF, respectively. The expression of Kv1.5 protein and messenger RNA (mRNA) were measured using Western blotting and polymerase chain reaction (PCR) method, respectively. Compared with the SR group, the expression of Kv1.5 protein decreased significantly in the AF group. However, neither Kv1.5 protein nor KCNA5 mRNA had significant differences in adult and aged groups, non-RHD and RHD group, and men and women group of AF. The expression of Kv1.5 channel protein changes with AF but not with age, RHD, and sex in AF.

  17. 35-kV GaAs subnanosecond photoconductive switches

    Energy Technology Data Exchange (ETDEWEB)

    Pocha, M.D.; Druce, R.L. (Lawrence Livermore National Lab., CA (United States))

    1990-12-01

    Photoconductive switches are one of the few devices that allow the generation of high-voltage electrical pulses with subnanosecond rise time. The authors are exploring high-voltage, fast-pulse generation using GaAs photoconductive switches. They have been able to generate 35-kV pulses with rise times as short as 135 ps using 5-mm gap switches and have achieved electric field hold-off of greater than 100 kV/cm. They have also been able to generate an approximately 500-ps FWHM on/off electrical pulse with an amplitude of approximately 3 kV using neutron-irradiated GaAs having short carrier life times. This paper describes the experimental results and discusses fabrication of switches and the diagnostics used to measure these fast signals. They also describe the experience with the nonlinear lock-on and avalanche modes of operation observed in GaAs.

  18. AMP-activated protein kinase downregulates Kv7.1 cell surface expression

    DEFF Research Database (Denmark)

    Andersen, Martin N; Krzystanek, Katarzyna; Jespersen, Thomas

    2012-01-01

    in response to polarization of the epithelial Madin-Darby canine kidney (MDCK) cell line and that this was mediated by activation of protein kinase C (PKC). In this study, the pathway downstream of PKC, which leads to internalization of Kv7.1 upon cell polarization, is elucidated. We show by confocal...... microscopy that Kv7.1 is endocytosed upon initiation of the polarization process and sent for degradation by the lysosomal pathway. The internalization could be mimicked by pharmacological activation of the AMP-activated protein kinase (AMPK) using three different AMPK activators. We demonstrate...

  19. Research on Condition Assessment Method of Transmission Tower Under the Action of Strong Wind

    Science.gov (United States)

    Huang, Ren-mou; An, Li-qiang; Zhang, Rong-lun; Wu, Jiong; Liang, Ya-feng

    2018-03-01

    Transmission towers are often subjected to the external damage of severe weather like strong wind and so on, which may cause the collapse due to the yield and fracture of the tower material. Aiming this issue, an assessment method was proposed in this paper to assess the operation condition of transmission towers under strong wind. With a reasonable assess index system established firstly, then the internal force of the tower material was solved and its stability was determined through the mechanical analysis of the transmission tower finite element model. Meanwhile, the condition risk level of the tower was finally determined by considering the difference among the influences of other factors like corrosion and loose of members, slope on the transmission tower through the analytic hierarchy process. The assessment method was applied to assess the wind-induced collapse of towers in 110kV Bao Yi II line in Wenchang City, Hainan Province, of which the result proves the method can assess the condition of transmission tower under strong wind and of guiding significance for improving the windproof capability of transmission towers.

  20. A charge-pump 60kV modulator for the ISOLDE target extraction voltage

    CERN Document Server

    Barlow, R A; Fowler, A; Gaudillet, H; Gharsa, T; Schipper, J

    2015-01-01

    The ISOLDE facility at CERN provides radioactive ion beams to a number of experimental stations. These ions are produced by a metal target, floating at 60 kV, which is impacted by a 1.4 GeV high intensity proton beam. The ions are then accelerated by a grounded extraction electrode to 60 keV, before transport to the experimental area. During proton beam impact extremely high ionisation of the volume around the target gives rise to significant leakage current which results in loss of charge on the effective target capacitance of approximately 6 nF. If short life-time isotopes are to be studied, the 60 kV must be re-established within a maximum of 10 ms. Recharging the target capacitance to 60 kV and to the required stability of better than 10-4 precludes a direct charging system and an alternative method of re-establishing the 60 kV is used. The present system [1], in operation since 1991, employs a resonant circuit which is triggered 35 µs prior to beam impact. This circuit transfers the charge on the effec...

  1. The Effect of Phase-to-earth Faults on the Operating Conditions of a Separated 110 kV Grid Normally Operated with Effectively Earthed Neutral, and Temporarily Supplied from a Compensated 110 kV Grid

    Directory of Open Access Journals (Sweden)

    Wilhelm Rojewski

    2015-06-01

    Full Text Available The paper discusses the interoperability of the German compensated 110 kV grid and the Polish effectively earthed 110 kV grid. It is assumed that an area of one grid, separated from its power system, will be temporarily supplied from the other grid in its normal regime. Reference is made to the risks associated with phase-to-earth faults in grids so interconnected. Particular attention is paid to the working conditions of surge arresters and voltage transformers in the Polish 110 kV grid deprived of its neutral earthing when supplied from the German grid.

  2. Visualizing Mutation-Specific Differences in the Trafficking-Deficient Phenotype of Kv11.1 Proteins Linked to Long QT Syndrome Type 2.

    Science.gov (United States)

    Hall, Allison R; Anderson, Corey L; Smith, Jennifer L; Mirshahi, Tooraj; Elayi, Claude S; January, Craig T; Delisle, Brian P

    2018-01-01

    KCNH2 encodes the Kv11.1 α-subunit that underlies the rapidly activating delayed-rectifier K + current in the heart. Loss-of-function KCNH2 mutations cause long QT syndrome type 2 (LQT2), and most LQT2-linked missense mutations inhibit the trafficking of Kv11.1 channel protein to the cell surface membrane. Several trafficking-deficient LQT2 mutations (e.g., G601S) generate Kv11.1 proteins that are sequestered in a microtubule-dependent quality control (QC) compartment in the transitional endoplasmic reticulum (ER). We tested the hypothesis that the QC mechanisms that regulate LQT2-linked Kv11.1 protein trafficking are mutation-specific. Confocal imaging analyses of HEK293 cells stably expressing the trafficking-deficient LQT2 mutation F805C showed that, unlike G601S-Kv11.1 protein, F805C-Kv11.1 protein was concentrated in several transitional ER subcompartments. The microtubule depolymerizing drug nocodazole differentially affected G601S- and F805C-Kv11.1 protein immunostaining. Nocodazole caused G601S-Kv11.1 protein to distribute into peripheral reticular structures, and it increased the diffuse immunostaining of F805C-Kv11.1 protein around the transitional ER subcompartments. Proteasome inhibition also affected the immunostaining of G601S- and F805C-Kv11.1 protein differently. Incubating cells in MG132 minimally impacted G601S-Kv11.1 immunostaining, but it dramatically increased the diffuse immunostaining of F805C-Kv11.1 protein in the transitional ER. Similar results were seen after incubating cells in the proteasome inhibitor lactacystin. Differences in the cellular distribution of G601S-Kv11.1 and F805C-Kv11.1 protein persisted in transfected human inducible pluripotent stem cell derived cardiomyocytes. These are the first data to visually demonstrate mutation-specific differences in the trafficking-deficient LQT2 phenotype, and this study has identified a novel way to categorize trafficking-deficient LQT2 mutations based on differences in intracellular

  3. Prospective application of advanced series compensation to improve transmission system performance

    Energy Technology Data Exchange (ETDEWEB)

    Gama, C A; Scavassa, J L; Silva, W.M. da; Silva, J M.M. da; Ponte, J R [ELETRONORTE, Brasilia, DF (Brazil)

    1994-12-31

    This paper describes the main aspects and results of the planning studies undertaken to evaluate the technical benefits of using Thyristor Controlled Series Compensation (TCSC), in a large 500 kV transmission system (Brazilian North-Northeast system). TCSC controllers design and simplified models for digital non-linear time domain simulations are discussed. The proposed controllers are tuned and used to support the comparative analysis between controlled and fixed series compensation. The relevant conclusions concerning this comparison are highlighted. (author) 2 refs., 14 figs., 3 tabs.

  4. Do kV really make everything look grey? A comparative study of 600 kV computed tomography systems; Macht kV wirklich grau? Eine Vergleichsstudie zu 600 kV Computertomografiesystemen

    Energy Technology Data Exchange (ETDEWEB)

    Krumm, Michael; Sauerwein, Christoph; Haemmerle, Volker; Knupe, Gunnar [RayScan Technologies GmbH, Meersburg (Germany)

    2013-07-01

    In the automotive industry there is a manufacture of cast aluminium parts of considerable thickness. Growing importance is being attached to methods of nondestructive testing and full metrological characterisation of these parts. A major contribution to this end has been made by the latest generation of CT systems, whose 600 kV X-ray tubes and line detectors make for excellent image quality. The purpose of the present study was to make an objective assessment of the performance of these CT systems by examining the advantages and drawbacks of each. This included comparisons of various parameters such as tube voltage and exposure time as well as different tube and detector technologies and CT measurement methods.

  5. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-124 (Echo Lake-Maple Valley #1 [Mile 9-16], Adno 8258)

    Energy Technology Data Exchange (ETDEWEB)

    Shurtliff, Aaron [Bonneville Power Administration (BPA), Portland, OR (United States)

    2003-02-18

    Vegetation Management for portion of the Echo Lake – Maple Valley #1 500 kV transmission line located from tower structure 9/2 to 16/5. BPA proposes to clear targeted vegetation within the Right-of-Ways along access roads and around towers that may impede the operation and maintenance of the subject transmission lines. See Section 1.4 of the attached checklists for a complete description of the proposed action.

  6. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-125 (Echo Lake-Maple Valley #1 [Mile 1-9], Adno 8258)

    Energy Technology Data Exchange (ETDEWEB)

    Shurtliff, Aaron [Bonneville Power Administration (BPA), Portland, OR (United States)

    2003-02-18

    Vegetation Management for portion of the Echo Lake – Maple Valley #1 500 kV transmission line located from tower structure 1/1 to 9/2. BPA proposes to clear targeted vegetation within the Right-of-Ways along access roads and around towers that may impede the operation and maintenance of the subject transmission lines. See Section 1.4 of the attached checklists for a complete description of the proposed action.

  7. Heteromeric Kv7.2/7.3 channels differentially regulate action potential initiation and conduction in neocortical myelinated axons.

    Science.gov (United States)

    Battefeld, Arne; Tran, Baouyen T; Gavrilis, Jason; Cooper, Edward C; Kole, Maarten H P

    2014-03-05

    Rapid energy-efficient signaling along vertebrate axons is achieved through intricate subcellular arrangements of voltage-gated ion channels and myelination. One recently appreciated example is the tight colocalization of K(v)7 potassium channels and voltage-gated sodium (Na(v)) channels in the axonal initial segment and nodes of Ranvier. The local biophysical properties of these K(v)7 channels and the functional impact of colocalization with Na(v) channels remain poorly understood. Here, we quantitatively examined K(v)7 channels in myelinated axons of rat neocortical pyramidal neurons using high-resolution confocal imaging and patch-clamp recording. K(v)7.2 and 7.3 immunoreactivity steeply increased within the distal two-thirds of the axon initial segment and was mirrored by the conductance density estimates, which increased from ~12 (proximal) to 150 pS μm(-2) (distal). The axonal initial segment and nodal M-currents were similar in voltage dependence and kinetics, carried by K(v)7.2/7.3 heterotetramers, 4% activated at the resting membrane potential and rapidly activated with single-exponential time constants (~15 ms at 28 mV). Experiments and computational modeling showed that while somatodendritic K(v)7 channels are strongly activated by the backpropagating action potential to attenuate the afterdepolarization and repetitive firing, axonal K(v)7 channels are minimally recruited by the forward-propagating action potential. Instead, in nodal domains K(v)7.2/7.3 channels were found to increase Na(v) channel availability and action potential amplitude by stabilizing the resting membrane potential. Thus, K(v)7 clustering near axonal Na(v) channels serves specific and context-dependent roles, both restraining initiation and enhancing conduction of the action potential.

  8. Design and Application of Cables and Overhead Lines in Wind Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Behnke, M. R. [IEEE PES Wind Plant Collector System Design Working Group; Bellei, T.A. [IEEE PES Wind Plant Collector System Design Working Group; Bloethe, W.G. [IEEE PES Wind Plant Collector System Design Working Group; Bradt, M. [IEEE PES Wind Plant Collector System Design Working Group; Brooks, C. [IEEE PES Wind Plant Collector System Design Working Group; Camm, E H [IEEE PES Wind Plant Collector System Design Working Group; Dilling, W. [IEEE PES Wind Plant Collector System Design Working Group; Goltz, B. [IEEE PES Wind Plant Collector System Design Working Group; Hermanson, J. [IEEE PES Wind Plant Collector System Design Working Group; Li, J. [IEEE PES Wind Plant Collector System Design Working Group; Loy, P. [IEEE PES Wind Plant Collector System Design Working Group; McLean, K. [IEEE PES Wind Plant Collector System Design Working Group; Niemira, J. [IEEE PES Wind Plant Collector System Design Working Group; Nuckles, K. [IEEE PES Wind Plant Collector System Design Working Group; Patino, J. [IEEE PES Wind Plant Collector System Design Working Group; Reza, M [IEEE PES Wind Plant Collector System Design Working Group; Richardson, B. [IEEE PES Wind Plant Collector System Design Working Group; Samaan, N. [IEEE PES Wind Plant Collector System Design Working Group; Schoene, Jens [IEEE PES Wind Plant Collector System Design Working Group; Smith, Travis M [ORNL; Snyder, Isabelle B [ORNL; Starke, Michael R [ORNL; Tesch, M. [IEEE PES Wind Plant Collector System Design Working Group; Walling, R. [IEEE PES Wind Plant Collector System Design Working Group; Zahalka, G. [IEEE PES Wind Plant Collector System Design Working Group

    2010-01-01

    This paper presents a summary of the most impor- tant considerations for wind power plant collection system un- derground and overhead cable designs. Various considerations, including conductor selection, soil thermal properties, installa- tion methods, splicing, concentric grounding, and NESC/NEC requirements are discussed.

  9. Eccentric and isometric shoulder rotator cuff strength testing using a hand-held dynamometer: reference values for overhead athletes.

    Science.gov (United States)

    Cools, Ann M J; Vanderstukken, Fran; Vereecken, Frédéric; Duprez, Mattias; Heyman, Karel; Goethals, Nick; Johansson, Fredrik

    2016-12-01

    In order to provide science-based guidelines for injury prevention or return to play, regular measurement of isometric and eccentric internal (IR) and external (ER) rotator strength is warranted in overhead athletes. However, up to date, no normative database exists regarding these values, when measured with a hand-held dynamometer. Therefore, the purpose of the study was to provide a normative database on isometric and eccentric rotator cuff (RC) strength values in a sample of overhead athletes, and to discuss gender, age and sports differences. A HHD was used to measure RC strength in 201 overhead athletes between 18 and 50 years old from three different sports disciplines: tennis, volleyball and handball. Isometric as well as eccentric strength was measured in different shoulder positions. Outcome variables of interest were isometric ER and IR strength, eccentric ER strength, and intermuscular strength ratios ER/IR. Our results show significant side, gender and sports discipline differences in the isometric and eccentric RC strength. However, when normalized to body weight, gender differences often are absent. In general, strength differences are in favour of the dominant side, the male athletes and handball. Intermuscular ER/IR ratios showed gender, sports, and side differences. This normative database is necessary to help the clinician in the evaluation of RC strength in healthy and injured overhead athletes. In view of the preventive screening and return-to-play decisions in overhead athletes, normalization to body weight and calculating intermuscular ratios are key points in this evaluation. Diagnostic study, Level III.

  10. MicroRNA-301a mediated regulation of Kv4.2 in diabetes: identification of key modulators.

    Directory of Open Access Journals (Sweden)

    Siva K Panguluri

    Full Text Available Diabetes is a metabolic disorder that ultimately results in major pathophysiological complications in the cardiovascular system. Diabetics are predisposed to higher incidences of sudden cardiac deaths (SCD. Several studies have associated diabetes as a major underlying risk for heart diseases and its complications. The diabetic heart undergoes remodeling to cope up with the underlying changes, however ultimately fails. In the present study we investigated the changes associated with a key ion channel and transcriptional factors in a diabetic heart model. In the mouse db/db model, we identified key transcriptional regulators and mediators that play important roles in the regulation of ion channel expression. Voltage-gated potassium channel (Kv4.2 is modulated in diabetes and is down regulated. We hypothesized that Kv4.2 expression is altered by potassium channel interacting protein-2 (KChIP2 which is regulated upstream by NFkB and miR-301a. We utilized qRT-PCR analysis and identified the genes that are affected in diabetes in a regional specific manner in the heart. At protein level we identified and validated differential expression of Kv4.2 and KChIP2 along with NFkB in both ventricles of diabetic hearts. In addition, we identified up-regulation of miR-301a in diabetic ventricles. We utilized loss and gain of function approaches to identify and validate the role of miR-301a in regulating Kv4.2. Based on in vivo and in vitro studies we conclude that miR-301a may be a central regulator for the expression of Kv4.2 in diabetes. This miR-301 mediated regulation of Kv4.2 is independent of NFkB and Irx5 and modulates Kv4.2 by direct binding on Kv4.2 3'untranslated region (3'-UTR. Therefore targeting miR-301a may offer new potential for developing therapeutic approaches.

  11. SU-F-J-54: Towards Real-Time Volumetric Imaging Using the Treatment Beam and KV Beam

    Energy Technology Data Exchange (ETDEWEB)

    Chen, M; Rozario, T; Liu, A; Jiang, S; Lu, W [UT Southwestern Medical Center, Dallas, TX (United States)

    2016-06-15

    Purpose: Existing real-time imaging uses dual (orthogonal) kV beam fluoroscopies and may result in significant amount of extra radiation to patients, especially for prolonged treatment cases. In addition, kV projections only provide 2D information, which is insufficient for in vivo dose reconstruction. We propose real-time volumetric imaging using prior knowledge of pre-treatment 4D images and real-time 2D transit data of treatment beam and kV beam. Methods: The pre-treatment multi-snapshot volumetric images are used to simulate 2D projections of both the treatment beam and kV beam, respectively, for each treatment field defined by the control point. During radiation delivery, the transit signals acquired by the electronic portal image device (EPID) are processed for every projection and compared with pre-calculation by cross-correlation for phase matching and thus 3D snapshot identification or real-time volumetric imaging. The data processing involves taking logarithmic ratios of EPID signals with respect to the air scan to reduce modeling uncertainties in head scatter fluence and EPID response. Simulated 2D projections are also used to pre-calculate confidence levels in phase matching. Treatment beam projections that have a low confidence level either in pre-calculation or real-time acquisition will trigger kV beams so that complementary information can be exploited. In case both the treatment beam and kV beam return low confidence in phase matching, a predicted phase based on linear regression will be generated. Results: Simulation studies indicated treatment beams provide sufficient confidence in phase matching for most cases. At times of low confidence from treatment beams, kV imaging provides sufficient confidence in phase matching due to its complementary configuration. Conclusion: The proposed real-time volumetric imaging utilizes the treatment beam and triggers kV beams for complementary information when the treatment beam along does not provide sufficient

  12. DEVELOPMENT AND INVESTIGATION OF LAYOUT OF ACTIVE SCREENING SYSTEM OF THE MAGNETIC FIELD GENERATED BY GROUP OF OVERHEAD TRANSMISSION LINES

    Directory of Open Access Journals (Sweden)

    B. I. Kuznetsov

    2018-04-01

    Full Text Available Purpose. Development and field experimental research of layout of the single-circuit active screening system of the magnetic field generated by group of high voltage transmission lines in residential area is given. Methodology. Mathematical model of magnetic field, generated by group of high voltage transmission lines in residential area, based of the experimental values of magnetic field flux density in given points on the basis of optimization problem solving is improved. The objective of the synthesis of the single circuit active screening system is to determine their number, configuration, spatial arrangement, wiring diagrams and compensation cables currents, setting algorithm of the control systems as well as the resulting value of the magnetic flux density at the points of the protected space. Synthesis of the full-scale model of active screening system is reduced to the problem of multiobjective nonlinear programming with constraints in which calculation of the objective functions and constraints are carried out on the basis of the Maxwell equations solutions in the quasi-stationary approximation. The problem is solved by a stochastic multiswarm multi-agent particles optimization. Results. The single-circuit active screening system synthesis results for reduction of a magnetic field generated by group of high voltage transmission lines in residential area is given. Field experimental researches of the single-circuit active screening system of the magnetic field generated by group of high voltage transmission lines in residential area with various control algorithms is given. Originality. For the first time out the development and field experimental studies of the single-circuit active screening system of the magnetic field generated by group of high voltage transmission lines in residential area are carried out. Practical value. Practical recommendations on reasonable choice of the spatial arrangement of compensating cables of single

  13. Allocating Overhead Costs in a Navy Working Capital Fund Environment: An Analysis and Comparison of Current Navy Policy and Private Sector Practice

    National Research Council Canada - National Science Library

    Schulte, Steven

    1999-01-01

    .... The objective of this thesis was to evaluate the overhead allocation practices of five private sector organizations for the potential improvement of overhead allocation practices in Navy Working Capital Fund activities...

  14. Anterior internal impingement of the shoulder in rugby players and other overhead athletes

    Directory of Open Access Journals (Sweden)

    Siddharth R. Shah, MBBS, MSc Sports Medicine (UK, MRCS-Ed

    2017-04-01

    Conclusion: This series of anterior internal impingement, which we believe is the largest in the literature to date, demonstrates the value of an to assess and successfully treat overhead athletes with anterior impingement syndrome.

  15. Performance of a 100-kV, 78-kJ electric-gun system

    International Nuclear Information System (INIS)

    Chau, H.; Dittbenner, G.; Mikkelsen, K.; Weingart, R.; Froeschner, K.; Lee, R.

    1981-01-01

    A new electric gun system was constructed for use in high-pressure EOS studies. The system is powered by a 100 kV, 15.6 μF capacitor bank. At 100 kV charging voltage the system inductance is 23 nH. This system has driven 0.3 mm-thick Kapton projectiles to > 20 km/s and 0.3 mm Kapton/30 μm Ta projectiles to approx. 10 km/s. Projectile velocity is modeled phenomenlogically by an electrical Gurney model

  16. An accurate method for computer-generating tungsten anode x-ray spectra from 30 to 140 kV.

    Science.gov (United States)

    Boone, J M; Seibert, J A

    1997-11-01

    A tungsten anode spectral model using interpolating polynomials (TASMIP) was used to compute x-ray spectra at 1 keV intervals over the range from 30 kV to 140 kV. The TASMIP is not semi-empirical and uses no physical assumptions regarding x-ray production, but rather interpolates measured constant potential x-ray spectra published by Fewell et al. [Handbook of Computed Tomography X-ray Spectra (U.S. Government Printing Office, Washington, D.C., 1981)]. X-ray output measurements (mR/mAs measured at 1 m) were made on a calibrated constant potential generator in our laboratory from 50 kV to 124 kV, and with 0-5 mm added aluminum filtration. The Fewell spectra were slightly modified (numerically hardened) and normalized based on the attenuation and output characteristics of a constant potential generator and metal-insert x-ray tube in our laboratory. Then, using the modified Fewell spectra of different kVs, the photon fluence phi at each 1 keV energy bin (E) over energies from 10 keV to 140 keV was characterized using polynomial functions of the form phi (E) = a0[E] + a1[E] kV + a2[E] kV2 + ... + a(n)[E] kVn. A total of 131 polynomial functions were used to calculate accurate x-ray spectra, each function requiring between two and four terms. The resulting TASMIP algorithm produced x-ray spectra that match both the quality and quantity characteristics of the x-ray system in our laboratory. For photon fluences above 10% of the peak fluence in the spectrum, the average percent difference (and standard deviation) between the modified Fewell spectra and the TASMIP photon fluence was -1.43% (3.8%) for the 50 kV spectrum, -0.89% (1.37%) for the 70 kV spectrum, and for the 80, 90, 100, 110, 120, 130 and 140 kV spectra, the mean differences between spectra were all less than 0.20% and the standard deviations were less than approximately 1.1%. The model was also extended to include the effects of generator-induced kV ripple. Finally, the x-ray photon fluence in the units of

  17. Metal artifact correction for x-ray computed tomography using kV and selective MV imaging

    International Nuclear Information System (INIS)

    Wu, Meng; Keil, Andreas; Constantin, Dragos; Star-Lack, Josh; Zhu, Lei; Fahrig, Rebecca

    2014-01-01

    Purpose: The overall goal of this work is to improve the computed tomography (CT) image quality for patients with metal implants or fillings by completing the missing kilovoltage (kV) projection data with selectively acquired megavoltage (MV) data that do not suffer from photon starvation. When both of these imaging systems, which are available on current radiotherapy devices, are used, metal streak artifacts are avoided, and the soft-tissue contrast is restored, even for regions in which the kV data cannot contribute any information. Methods: Three image-reconstruction methods, including two filtered back-projection (FBP)-based analytic methods and one iterative method, for combining kV and MV projection data from the two on-board imaging systems of a radiotherapy device are presented in this work. The analytic reconstruction methods modify the MV data based on the information in the projection or image domains and then patch the data onto the kV projections for a FBP reconstruction. In the iterative reconstruction, the authors used dual-energy (DE) penalized weighted least-squares (PWLS) methods to simultaneously combine the kV/MV data and perform the reconstruction. Results: The authors compared kV/MV reconstructions to kV-only reconstructions using a dental phantom with fillings and a hip-implant numerical phantom. Simulation results indicated that dual-energy sinogram patch FBP and the modified dual-energy PWLS method can successfully suppress metal streak artifacts and restore information lost due to photon starvation in the kV projections. The root-mean-square errors of soft-tissue patterns obtained using combined kV/MV data are 10–15 Hounsfield units smaller than those of the kV-only images, and the structural similarity index measure also indicates a 5%–10% improvement in the image quality. The added dose from the MV scan is much less than the dose from the kV scan if a high efficiency MV detector is assumed. Conclusions: The authors have shown that it

  18. Metal artifact correction for x-ray computed tomography using kV and selective MV imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Meng, E-mail: mengwu@stanford.edu [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Keil, Andreas [microDimensions GmbH, Munich 81379 (Germany); Constantin, Dragos; Star-Lack, Josh [Varian Medical Systems, Inc., Palo Alto, California 94304 (United States); Zhu, Lei [Nuclear and Radiological Engineering and Medical Physics Programs, The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2014-12-15

    Purpose: The overall goal of this work is to improve the computed tomography (CT) image quality for patients with metal implants or fillings by completing the missing kilovoltage (kV) projection data with selectively acquired megavoltage (MV) data that do not suffer from photon starvation. When both of these imaging systems, which are available on current radiotherapy devices, are used, metal streak artifacts are avoided, and the soft-tissue contrast is restored, even for regions in which the kV data cannot contribute any information. Methods: Three image-reconstruction methods, including two filtered back-projection (FBP)-based analytic methods and one iterative method, for combining kV and MV projection data from the two on-board imaging systems of a radiotherapy device are presented in this work. The analytic reconstruction methods modify the MV data based on the information in the projection or image domains and then patch the data onto the kV projections for a FBP reconstruction. In the iterative reconstruction, the authors used dual-energy (DE) penalized weighted least-squares (PWLS) methods to simultaneously combine the kV/MV data and perform the reconstruction. Results: The authors compared kV/MV reconstructions to kV-only reconstructions using a dental phantom with fillings and a hip-implant numerical phantom. Simulation results indicated that dual-energy sinogram patch FBP and the modified dual-energy PWLS method can successfully suppress metal streak artifacts and restore information lost due to photon starvation in the kV projections. The root-mean-square errors of soft-tissue patterns obtained using combined kV/MV data are 10–15 Hounsfield units smaller than those of the kV-only images, and the structural similarity index measure also indicates a 5%–10% improvement in the image quality. The added dose from the MV scan is much less than the dose from the kV scan if a high efficiency MV detector is assumed. Conclusions: The authors have shown that it

  19. Metal artifact correction for x-ray computed tomography using kV and selective MV imaging.

    Science.gov (United States)

    Wu, Meng; Keil, Andreas; Constantin, Dragos; Star-Lack, Josh; Zhu, Lei; Fahrig, Rebecca

    2014-12-01

    The overall goal of this work is to improve the computed tomography (CT) image quality for patients with metal implants or fillings by completing the missing kilovoltage (kV) projection data with selectively acquired megavoltage (MV) data that do not suffer from photon starvation. When both of these imaging systems, which are available on current radiotherapy devices, are used, metal streak artifacts are avoided, and the soft-tissue contrast is restored, even for regions in which the kV data cannot contribute any information. Three image-reconstruction methods, including two filtered back-projection (FBP)-based analytic methods and one iterative method, for combining kV and MV projection data from the two on-board imaging systems of a radiotherapy device are presented in this work. The analytic reconstruction methods modify the MV data based on the information in the projection or image domains and then patch the data onto the kV projections for a FBP reconstruction. In the iterative reconstruction, the authors used dual-energy (DE) penalized weighted least-squares (PWLS) methods to simultaneously combine the kV/MV data and perform the reconstruction. The authors compared kV/MV reconstructions to kV-only reconstructions using a dental phantom with fillings and a hip-implant numerical phantom. Simulation results indicated that dual-energy sinogram patch FBP and the modified dual-energy PWLS method can successfully suppress metal streak artifacts and restore information lost due to photon starvation in the kV projections. The root-mean-square errors of soft-tissue patterns obtained using combined kV/MV data are 10-15 Hounsfield units smaller than those of the kV-only images, and the structural similarity index measure also indicates a 5%-10% improvement in the image quality. The added dose from the MV scan is much less than the dose from the kV scan if a high efficiency MV detector is assumed. The authors have shown that it is possible to improve the image quality of

  20. Measuring electromagnetic fields (EMF) around wind turbines in Canada: is there a human health concern?

    Science.gov (United States)

    McCallum, Lindsay C; Whitfield Aslund, Melissa L; Knopper, Loren D; Ferguson, Glenn M; Ollson, Christopher A

    2014-02-15

    The past five years has seen considerable expansion of wind power generation in Ontario, Canada. Most recently worries about exposure to electromagnetic fields (EMF) from wind turbines, and associated electrical transmission, has been raised at public meetings and legal proceedings. These fears have not been based on any actual measurements of EMF exposure surrounding existing projects but appear to follow from worries from internet sources and misunderstanding of the science. The study was carried out at the Kingsbridge 1 Wind Farm located near Goderich, Ontario, Canada. Magnetic field measurements were collected in the proximity of 15 Vestas 1.8 MW wind turbines, two substations, various buried and overhead collector and transmission lines, and nearby homes. Data were collected during three operational scenarios to characterize potential EMF exposure: 'high wind' (generating power), 'low wind' (drawing power from the grid, but not generating power) and 'shut off' (neither drawing, nor generating power). Background levels of EMF (0.2 to 0.3 mG) were established by measuring magnetic fields around the wind turbines under the 'shut off' scenario. Magnetic field levels detected at the base of the turbines under both the 'high wind' and 'low wind' conditions were low (mean = 0.9 mG; n = 11) and rapidly diminished with distance, becoming indistinguishable from background within 2 m of the base. Magnetic fields measured 1 m above buried collector lines were also within background (≤ 0.3 mG). Beneath overhead 27.5 kV and 500 kV transmission lines, magnetic field levels of up to 16.5 and 46 mG, respectively, were recorded. These levels also diminished rapidly with distance. None of these sources appeared to influence magnetic field levels at nearby homes located as close as just over 500 m from turbines, where measurements immediately outside of the homes were ≤ 0.4 mG. The results suggest that there is nothing unique to wind farms with respect to EMF exposure; in

  1. Localization and function of the Kv3.1b subunit in the rat medulla oblongata: focus on the nucleus tractus solitarii

    Science.gov (United States)

    Dallas, Mark L; Atkinson, Lucy; Milligan, Carol J; Morris, Neil P; Lewis, David I; Deuchars, Susan A; Deuchars, Jim

    2005-01-01

    The voltage-gated potassium channel subunit Kv3.1 confers fast firing characteristics to neurones. Kv3.1b subunit immunoreactivity (Kv3.1b-IR) was widespread throughout the medulla oblongata, with labelled neurones in the gracile, cuneate and spinal trigeminal nuclei. In the nucleus of the solitary tract (NTS), Kv3.1b-IR neurones were predominantly located close to the tractus solitarius (TS) and could be GABAergic or glutamatergic. Ultrastructurally, Kv3.1b-IR was detected in NTS terminals, some of which were vagal afferents. Whole-cell current-clamp recordings from neurones near the TS revealed electrophysiological characteristics consistent with the presence of Kv3.1b subunits: short duration action potentials (4.2 ± 1.4 ms) and high firing frequencies (68.9 ± 5.3 Hz), both sensitive to application of TEA (0.5 mm) and 4-aminopyridine (4-AP; 30 μm). Intracellular dialysis of an anti-Kv3.1b antibody mimicked and occluded the effects of TEA and 4-AP in NTS and dorsal column nuclei neurones, but not in dorsal vagal nucleus or cerebellar Purkinje cells (which express other Kv3 subunits, but not Kv3.1b). Voltage-clamp recordings from outside-out patches from NTS neurones revealed an outward K+ current with the basic characteristics of that carried by Kv3 channels. In NTS neurones, electrical stimulation of the TS evoked EPSPs and IPSPs, and TEA and 4-AP increased the average amplitude and decreased the paired pulse ratio, consistent with a presynaptic site of action. Synaptic inputs evoked by stimulation of a region lacking Kv3.1b-IR neurones were not affected, correlating the presence of Kv3.1b in the TS with the pharmacological effects. PMID:15528247

  2. In situ electrical probing and bias-mediated manipulation of dielectric nanotubes in a high-resolution transmission electron microscope

    International Nuclear Information System (INIS)

    Golberg, D.; Mitome, M.; Kurashima, K.; Zhi, C.Y.; Tang, C.C.; Bando, Y.; Lourie, O.

    2006-01-01

    Boron nitride nanotubes filled with magnesium oxides [MgO, MgO 2 ] and/or hydroxide [Mg(OH) 2 ] are electrically probed and delicately manipulated inside a 300 kV JEOL-3000F high-resolution transmission analytical electron microscope equipped with a side-entry 'Nanofactory Instruments' piezoholder. At a low bias the nanotubes demonstrate truly insulating behavior. At a high bias of ±30 V they show reversible breakdown current of several dozens of nA. Under 300 kV electron beam irradiation the nanotubes are positively charged that allows us to perform on-demand manipulation with them through tuning of polarity and/or value of a bias voltage on a gold counterelectrode from -140 to +140 V, owing to the prominent electrostatic nanotube-electrode interactions

  3. Improvement of the 400 kV linac electron source of AmPS

    International Nuclear Information System (INIS)

    Kroes, F.B.; Beuzekom, M.G. van; Dobbe, N.J.; Es, J.T. van; Jansweijer, P.P.M.; Kruijer, A.H.; Luigjes, G.; Sluijk, T.G.B.

    1992-01-01

    An existing linac (MEA) injects electrons into the Amsterdam Pulse Stretcher (AmPS) ring. The linac's peak current increases from 20 to 80 mA. This requires the modification of the 400 kV low emittance gun. The fourfold increase of the peak current is obtained by doubling both the gun perveance (new gun part) and the pulsed extractor voltage. To obtain optimum beam quality over this increased current range, the hot deck electronics has been exchanged by a fast high voltage FET switching supply. A built-in microprocessor, coupled to the local computer by optical fibers, is used to monitor and control the gun parameters. The 5 kV gun extractor voltage pulse shape can be monitored by means of an analog fibre transducer with build in calibration. Finally, in order to improve the energy stability of the accelerated electrons, a serial electron-tube stabilizer was added to the 400 kV DC power supply. (K.A.) 4 refs.; 6 figs

  4. S3b amino acid substitutions and ancillary subunits alter the affinity of Heteropoda venatoria toxin 2 for Kv4.3.

    Science.gov (United States)

    DeSimone, Christopher V; Lu, YiChun; Bondarenko, Vladimir E; Morales, Michael J

    2009-07-01

    Heteropoda venatoria toxin 2 (HpTx2) is an inhibitor cystine knot (ICK)-gating modifier toxin that selectively inhibits Kv4 channels. To characterize the molecular determinants of interaction, we performed alanine scanning of the Kv4.3 S3b region. HpTx2-Kv4.3 interaction had an apparent K(d) value of 2.3 microM. Two alanine mutants in Kv4.3 increased K(d) values to 6.4 microM for V276A and 25 microM for L275A. Simultaneous mutation of both amino acids to alanine nearly eliminated toxin interaction. Unlike Hanatoxin and other well characterized ICK toxins, HpTx2 binding does not require a charged amino acid for interaction. To determine whether the identity of the S3b binding site amino acids altered HpTx2 specificity, we constructed Kv4.3 [LV275IF]. This mutation decreased the K(d) value to 0.54 microM, suggesting that the hydrophobic character of the putative binding site is the most important property for interaction with HpTx2. One mutant, N280A, caused stronger interaction of HpTx2 with Kv4.3; the K(d) value for Kv4.3 [N280A] was 0.26 microM. To understand Kv4.3-based transient outward currents in native tissues, we tested the affinity of HpTx2 for Kv4.3 coexpressed with KChIP2b. The toxin's K(d) value for Kv4.3 + KChIP2b was 0.95 microM. KChIP2b stabilizes the closed state of Kv4.3, suggesting that the increased toxin affinity is due to increased stabilization of the closed state. These data show that HpTx2 binding to Kv4.3 has aspects in common with other ICK gating modifier toxins but that the interventions that increase toxin affinity suggest flexibility toward channel binding that belies its unusual specificity for Kv4 channels.

  5. BPA/Puget Power Northwest Washington Transmission Project Final Environmental Impact Statement.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1995-08-01

    Bonneville Power Administration (BPA) and Puget Sound Power & Light Company (Puget Power) propose to upgrade the existing high-voltage transmission system in the Whatcom and Skagit counties area between the towns of Custer and Sedro Woolley, including some areas within the City of Bellingham, starting in 1995. A Draft Environmental Impact Statement (DEIS) for the project was issued in November 1993, followed by a 45-day public comment period. Public response to the DEIS included the identification of several new transmission route alternatives in the Lake Whatcom area. BPA issued a Supplemental DEIS in April 1995 to provide a second public review-and-comment period. Rebuilding an existing 230-kV line to a double-circuit 230-kV transmission line was identified in the Supplemental DEIS as the Proposed Action. The Supplemental DEIS also examined in detail a North Shore Road alternative which was proposed by some members of the public. Public comments on the EIS were listed and responded to in the Supplemental DEIS. In May 1995, a second set of open houses and public meetings was held to review the Supplemental DEIS. Electromagnetic field (EMF) effects raised as an issue in the DEIS continued to be an issue of public concern in the meetings. The EIS has identified impacts that would generally be classified as low to moderate and localized. Effects on soils and water resources in sensitive areas (e.g., near Lake Whatcom) would be low to moderate; there would be little change in magnetic fields; noise levels would remain at existing levels; and land use and property value impacts would be minimal. Threatened and endangered species would not be adversely affected, and all proposed actions in wetlands would be covered by a Corps of Engineers Nationwide Permit. Visual and socioeconomic would be low to moderate. There would be no effect on cultural resources.

  6. Prevention of shoulder injuries in overhead athletes: a science-based approach

    Directory of Open Access Journals (Sweden)

    Ann M. Cools

    2015-10-01

    Full Text Available The shoulder is at high risk for injury during overhead sports, in particular in throwing or hitting activities, such as baseball, tennis, handball, and volleyball. In order to create a scientific basis for the prevention of recurrent injuries in overhead athletes, four steps need to be undertaken: (1 risk factors for injury and re-injury need to be defined; (2 established risk factors may be used as return-to-play criteria, with cut-off values based on normative databases; (3 these variables need to be measured using reliable, valid assessment tools and procedures; and (4 preventative training programs need to be designed and implemented into the training program of the athlete in order to prevent re-injury. In general, three risk factors have been defined that may form the basis for recommendations for the prevention of recurrent injury and return to play after injury: glenohumeral internal-rotation deficit (GIRD; rotator cuff strength, in particular the strength of the external rotators; and scapular dyskinesis, in particular scapular position and strength.

  7. Dimensional verification and location of the reactive static compensator in 220 kV; Verificacion del dimensionamiento y ubicacion del compensador estatico de reactivos en 220 kV

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Krekeler, Ubaldo [Administracion Nacional de Electricidad (ANDE), Asuncion (Paraguay)]. E-mail: ufernandez@ieee.org; Cardozo Sanchez, Freddy [Mirant Americas (United States)

    2001-07-01

    This work presents a determination verification of the compensation range and the location of reactive static compensator (RSC) in 220 kV. The verification is accomplished by analyses of the RSC effects in relation to the losses, loading and system voltage stability. The needed compensation range is investigated in full details, whereas that the required conversion level is directly related to this range. It is concluded that the RSC installation, foreseen for 2002, might be postponed for 2005/10 still without reinforcements in 500 kV. The Limpio substation seems to be the more suitable location in relation to the most analysed cases.

  8. Overhead mining railway, particularly for underground use

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, L

    1976-05-20

    Overhead mining railways are usually equipped with a friction wheel drive in underground use. This drive has the advantage over a gear drive that it is more robust and therefore more economic. However, it produces unsatisfactory running for difficult sections with steep gradients up or down or places where deposits of grease and dirt are inevitable. It is proposed to change over to a gear drive at such sections. The high degree of wear, which is characteristic of this type of drive, can be reduced if the drive is only used in difficult sections. It is proposed that the gear drive should be automatically switched on and off by means of stops or contacts on the rails.

  9. Structure-property relationships in an Al matrix Ca nanofilamentary composite conductor with potential application in high-voltage power transmission

    Science.gov (United States)

    Tian, Liang

    This study investigated the processing-structure-properties relationships in an Al/Ca composites using both experiments and modeling/simulation. A particular focus of the project was understanding how the strength and electrical conductivity of the composite are related to its microstructure in the hope that a conducting material with light weight, high strength, and high electrical conductivity can be developed to produce overhead high-voltage power transmission cables. The current power transmission cables (e.g., Aluminum Conductor Steel Reinforced (ACSR)) have acceptable performance for high-voltage AC transmission, but are less well suited for high-voltage DC transmission due to the poorly conducting core materials that support the cable weight. This Al/Ca composite was produced by powder metallurgy and severe plastic deformation by extrusion and swaging. The fine Ca metal powders have been produced by centrifugal atomization with rotating liquid oil quench bath, and a detailed study about the atomization process and powder characteristics has been conducted. The microstructure of Al/Ca composite was characterized by electron microscopy. Microstructure changes at elevated temperature were characterized by thermal analysis and indirect resistivity tests. The strength and electrical conductivity were measured by tensile tests and four-point probe resistivity tests. Predicting the strength and electrical conductivity of the composite was done by micro-mechanics-based analytical modeling. Microstructure evolution was studied by mesoscale-thermodynamics-based phase field modeling and a preliminary atomistic molecular dynamics simulation. The application prospects of this composite was studied by an economic analysis. This study suggests that the Al/Ca (20 vol. %) composite shows promise for use as overhead power transmission cables. Further studies are needed to measure the corrosion resistance, fatigue properties and energized field performance of this composite.

  10. Marangoni Flowers and the Evil Eye: Overhead Presentations of Marangoni Flow

    Science.gov (United States)

    Mundell, Donald W.

    2009-01-01

    Intermolecular forces and surface tension gradients in solutions lead to remarkable flows, known as Marangoni flows, where liquid flows from a region of low surface tension towards higher surface tension. Details of these flows, not visible to the naked eye, are made visible on an overhead projector owing to variation in the index of refraction.…

  11. New Concept of PLC Modems: Multi-Carrier System for Frequency Selective Slow-Fading Channels Based on Layered SCCC Turbocodes

    Directory of Open Access Journals (Sweden)

    J. Zavrtalek

    2015-09-01

    Full Text Available The article introduces a novel concept of a PLC modem as a complement to the existing G3 and PRIME standards for communications using medium- or high-voltage overhead or cable lines. The proposed concept is based on the fact that the levels of impulse noise and frequency selectivity are lower on high-voltage lines than on low-voltage ones. Also, the demands for “cost-effective” circuitry design are not so crucial as in the case of modems for low-voltage level. In contract to these positive conditions, however, there is the need to overcome much longer distances and to take into account low SNR on the receiving side. With respect to the listed reasons, our concept makes use of MCM, instead of OFDM. The assumption of low SNR is compensated through the use of an efficient channel coding based on a serially concatenated turbo code. In addition, MCM offers lower latency and PAPR compared to OFDM. Therefore, when using MCM, it is possible to excite the line with higher power. The proposed concept has been verified during experimental transmission of testing data over a real, 5 km long, 22kV overhead line.

  12. A Common Structural Component for β-Subunit Mediated Modulation of Slow Inactivation in Different KV Channels

    DEFF Research Database (Denmark)

    Strutz-Seebohm, Nathalie; Henrion, Ulrike; Schmitt, Nicole

    2013-01-01

    Background/Aims: Potassium channels are tetrameric proteins providing potassium selective passage through lipid embedded proteinaceous pores with highest fidelity. The selectivity results from binding to discrete potassium binding sites and stabilization of a hydrated potassium ion in a central...... internal cavity. The four potassium binding sites, generated by the conserved TTxGYGD signature sequence are formed by the backbone carbonyls of the amino acids TXGYG. Residues KV1.5-Val481, KV4.3-Leu368 and KV7.1- Ile 313 represent the amino acids in the X position of the respective channels. Methods...

  13. APETx4, a Novel Sea Anemone Toxin and a Modulator of the Cancer-Relevant Potassium Channel KV10.1

    Directory of Open Access Journals (Sweden)

    Lien Moreels

    2017-09-01

    Full Text Available The human ether-à-go-go channel (hEag1 or KV10.1 is a cancer-relevant voltage-gated potassium channel that is overexpressed in a majority of human tumors. Peptides that are able to selectively inhibit this channel can be lead compounds in the search for new anticancer drugs. Here, we report the activity-guided purification and electrophysiological characterization of a novel KV10.1 inhibitor from the sea anemone Anthopleura elegantissima. Purified sea anemone fractions were screened for inhibitory activity on KV10.1 by measuring whole-cell currents as expressed in Xenopus laevis oocytes using the two-microelectrode voltage clamp technique. Fractions that showed activity on Kv10.1 were further purified by RP-HPLC. The amino acid sequence of the peptide was determined by a combination of MALDI- LIFT-TOF/TOF MS/MS and CID-ESI-FT-ICR MS/MS and showed a high similarity with APETx1 and APETx3 and was therefore named APETx4. Subsequently, the peptide was electrophysiologically characterized on KV10.1. The selectivity of the toxin was investigated on an array of voltage-gated ion channels, including the cardiac human ether-à-go-go-related gene potassium channel (hERG or Kv11.1. The toxin inhibits KV10.1 with an IC50 value of 1.1 μM. In the presence of a similar toxin concentration, a shift of the activation curve towards more positive potentials was observed. Similar to the effect of the gating modifier toxin APETx1 on hERG, the inhibition of Kv10.1 by the isolated toxin is reduced at more positive voltages and the peptide seems to keep the channel in a closed state. Although the peptide also induces inhibitory effects on other KV and NaV channels, it exhibits no significant effect on hERG. Moreover, APETx4 induces a concentration-dependent cytotoxic and proapoptotic effect in various cancerous and noncancerous cell lines. This newly identified KV10.1 inhibitor can be used as a tool to further characterize the oncogenic channel KV10.1 or as a

  14. High-tension electrical-arc-induced thermal burns caused by railway overhead cables.

    Science.gov (United States)

    Koller, J

    1991-10-01

    Eleven patients with high-tension electrical-arc-induced thermal burns due to railway overhead cables were treated at the Bratislava Burn Department during a relatively short period of 18 months. All the injuries occurred by the same mechanism, that is persons climbing on top of railway carriages and approaching the 25,000 V a.c. overhead cables. All the burns were the result of an electrical arc passing externally to the body, with subsequent ignition of the victim's clothes. The cutaneous burns, ranging from 24 to 79 per cent of the BSA, were mostly deep partial to full skin thickness injuries. One patient died on day 5 postburn, the other survived. In spite of high-tension aetiology, no true electrical injuries appear to have occurred and no amputations were necessary. The pathophysiology and possible preventive measures are discussed. It must be stressed that arcing can be induced by an earthed object approaching, but not touching, a cable carrying a high voltage.

  15. 100-Gb/s 80-km transmission of PIM-SSB-OFDM at C-band using a single-end photodetector

    Science.gov (United States)

    Huo, Jiahao; Zhou, Xian; Zhong, Kangping; Gui, Tao; Tan, Fengze; Tu, Jiajing; Yuan, Jinhui; Zhang, Hongyu; Long, Keping; Yu, Changyuan; Lau, Alan Pak Tao; Lu, Chao

    2017-10-01

    Polarization-interleave-multiplexed (PIM) with single-sideband orthogonal frequency-division multiplexing (SSB-OFDM) based on direct detection is proposed for short-reach applications transmitted up to 80 km in which the guard band can be shared for the two SSB signals with interleave electrical center frequencies. Based on two dual-drive Mach-Zehnder modulators with one single-end photodetector (PD), 100-Gb/s PIM-SSB-OFDM transmission over a 80-km standard single-mode fiber is successfully demonstrated. After 80-km transmission, the optical signal-to-noise ratio requirement is 29.1 dB with respect to the bit error rate threshold of 7% hard decision-forward error correction overhead.

  16. The Use of Probability Theory as a Basis for Planning and Controlling Overhead Costs in Education and Industry. Final Report.

    Science.gov (United States)

    Vinson, R. B.

    In this report, the author suggests changes in the treatment of overhead costs by hypothesizing that "the effectiveness of standard costing in planning and controlling overhead costs can be increased through the use of probability theory and associated statistical techniques." To test the hypothesis, the author (1) presents an overview of the…

  17. A multi-objective framework for dynamic transmission expansion planning in competitive electricity market

    International Nuclear Information System (INIS)

    Foroud, Asghar Akbari; Abdoos, Ali Akbar; Keypour, Reza; Amirahmadi, Meisam

    2010-01-01

    Restructuring of power system has changed the traditional planning objectives and introduced challenges in the field of Transmission Expansion Planning (TEP). Due to these changes, new approaches and criteria are needed for transmission planning in deregulated environment. Therefore, in this paper, a dynamic expansion methodology is presented using a multi-objective optimization framework. Investment cost, congestion cost and reliability are considered in the optimization as three objectives. To overcome the difficulties in solving the non-convex and mixed integer nature of the optimization problems, a Non-Dominated Sorting Genetic Algorithm (NSGA II) approach is used followed by a fuzzy decision making analysis to obtain the final optimal solution. The planning methodology has been demonstrated on the IEEE 24-bus test system and north-east of Iran national 400 kV transmission grid to show the feasibility and capabilities of the proposed algorithm in electricity market environment. (author)

  18. Transmission Algorithm with QoS Considerations for a Sustainable MPEG Streaming Service

    Directory of Open Access Journals (Sweden)

    Sang-Hyong Kim

    2017-03-01

    Full Text Available With the proliferation of heterogeneous networks, there is a need to provide multimedia stream services in a sustainable manner. It is especially critical to maintain the Quality of Service (QoS standards. Existing multimedia streaming services have been studied to guarantee QoS on the receiving side. QoS has not been ensured due to the fact that the loss of streaming data to be transmitted has not been considered in network conditions. With an algorithm that considers the QoS and can reduce the overhead of the network, it will be possible to reduce the transmission error and wastage of communication network resources. In this paper, we propose a scheme that improves the reliability of multimedia transmissions by using an adaptive algorithm that switches between UDP (User Datagram Protocol and TCP (Transmission Control Protocol based on the size of the data. In addition, we present a method that retransmits essential portions of the multimedia data, thus improving transmission efficiency. We simulate an MPEG (Moving Picture Experts Group stream service and evaluate the performance of the proposed adaptive MPEG stream service.

  19. Clofazimine inhibits human Kv1.3 potassium channel by perturbing calcium oscillation in T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Yunzhao R Ren

    Full Text Available The Kv1.3 potassium channel plays an essential role in effector memory T cells and has been implicated in several important autoimmune diseases including multiple sclerosis, psoriasis and type 1 diabetes. A number of potent small molecule inhibitors of Kv1.3 channel have been reported, some of which were found to be effective in various animal models of autoimmune diseases. We report herein the identification of clofazimine, a known anti-mycobacterial drug, as a novel inhibitor of human Kv1.3. Clofazimine was initially identified as an inhibitor of intracellular T cell receptor-mediated signaling leading to the transcriptional activation of human interleukin-2 gene in T cells from a screen of the Johns Hopkins Drug Library. A systematic mechanistic deconvolution revealed that clofazimine selectively blocked the Kv1.3 channel activity, perturbing the oscillation frequency of the calcium-release activated calcium channel, which in turn led to the inhibition of the calcineurin-NFAT signaling pathway. These effects of clofazimine provide the first line of experimental evidence in support of a causal relationship between Kv1.3 and calcium oscillation in human T cells. Furthermore, clofazimine was found to be effective in blocking human T cell-mediated skin graft rejection in an animal model in vivo. Together, these results suggest that clofazimine is a promising immunomodulatory drug candidate for treating a variety of autoimmune disorders.

  20. Defense Outsourcing: Better Data Needed to Support Overhead Rates for A-76 Studies

    National Research Council Canada - National Science Library

    1998-01-01

    .... Specifically, this report addresses (1) what is the basis for OMB's new requirement that a standardized 12-percent overhead rate be applied to in-house cost estimates, regardless of the type of commercial activity or where in the country...