Sample records for submarine cable security

  1. North American Submarine Cable Association (NASCA) Submarine Cables (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data show the locations of in-service and out-of-service submarine cables that are owned by members of NASCA and located in U.S. territorial waters. More...

  2. A novel positioning method for dual Mach-Zehnder interferometric vibration sensor in submarine cable security application (United States)

    Xie, Shangran; Zhang, Min; Li, Yanhe; Liao, Yanbiao


    Dual Mach-Zehnder interferometric vibration sensor is an appropriate solution for submarine cable security application. While in this application the detected vibration signal is always narrow-bandwidth and short-duration subject to environmental constraints, which makes correlation based vibration positioning algorithm a poor robustness to noise. A preprocessing method focusing on expanding signal 3dB bandwidth before correlation is proposed in purpose of reducing ultimate positioning mean square error. A high pass filter is imposed to enhance the weight of high frequency components by attenuating low frequency main lobe. Field test results indicate a significant positioning error reduction when using this novel method as long as the cutoff frequency of high pass filter is selected in a valid region where positive effect of bandwidth extension is larger than effect of SNR reduction, and MSE reduction value in valid region agrees well with theoretical prediction.

  3. MVAC Submarine cable, impedance measurements and analysis

    DEFF Research Database (Denmark)

    Arentsen, Martin Trolle; Pedersen, Morten Virklund; Expethit, Adrian


    Due to environmental concerns an increase in off-shore windfarms has been observed in recent years, leading to an increased demand for three-core-wire-armoured submarine cables. However, the IEC Standard 60287 used to calculate the ampacity of these cables is widely recognized as being not accurate...

  4. Submarine Telecommunication Cables in Disputed Maritime Areas

    NARCIS (Netherlands)

    van Logchem, Youri


    There are a considerable number of maritime areas where no boundary exists, or where a boundary is delimited only in part. This article deals with the issue of submarine telecommunication cables, which are sometimes placed on the seabed or buried in the subsoil of areas that are claimed by multiple

  5. Environmental assessment of submarine power cables

    Energy Technology Data Exchange (ETDEWEB)

    Isus, Daniel; Martinez, Juan D. [Grupo General Cable Sistemas, S.A., 08560-Manlleu, Barcelona (Spain); Arteche, Amaya; Del Rio, Carmen; Madina, Virginia [Tecnalia Research and Innovation, 20009 San Sebastian (Spain)


    Extensive analyses conducted by the European Community revealed that offshore wind energy have relatively benign effects on the marine environment by comparison to other forms of electric power generation [1]. However, the materials employed in offshore wind power farms suffer major changes to be confined to the marine environment at extreme conditions: saline medium, hydrostatic pressure... which can produce an important corrosion effect. This phenomenon can affect on the one hand, to the material from the structural viewpoint and on the other hand, to the marine environment. In this sense, to better understand the environmental impacts of generating electricity from offshore wind energy, this study evaluated the life cycle assessment for some new designs of submarine power cables developed by General Cable. To achieve this goal, three approaches have been carried out: leaching tests, eco-toxicity tests and Life Cycle Assessment (LCA) methodologies. All of them are aimed to obtaining quantitative data for environmental assessment of selected submarine cables. LCA is a method used to assess environmental aspects and potential impacts of a product or activity. LCA does not include financial and social factors, which means that the results of an LCA cannot exclusively form the basis for assessment of a product's sustainability. Leaching tests results allowed to conclude that pH of seawater did not significantly changed by the presence of submarine three-core cables. Although, it was slightly higher in case of broken cable, pH values were nearly equals. Concerning to the heavy metals which could migrate to the aquatic medium, there were significant differences in both scenarios. The leaching of zinc is the major environmental concern during undersea operation of undamaged cables whereas the fully sectioned three-core cable produced the migration of significant quantities of copper and iron apart from the zinc migrated from the galvanized steel. Thus, the tar

  6. North Sea submarine cable disruptions and fishing activity

    NARCIS (Netherlands)

    Hintzen, N.T.; Machiels, M.A.M.


    At the North Sea seafloor, numerous submarine cables are positioned that connect telecommunication networks between countries. Worldwide, human activities cause most of the cable disruptions with fisheries accounting for nearly half of all reported faults. Due to a recent increase of submarine cable

  7. Submarine Cable Lines - USACE IENC (United States)

    Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

  8. Losses in armoured three-phase submarine cables

    DEFF Research Database (Denmark)

    Ebdrup, Thomas; Silva, Filipe Miguel Faria da; Bak, Claus Leth


    increases the losses in armoured cables compared to unarmoured cables. In this paper a thorough state of the art analysis is conducted on armour losses in three-phase armoured submarine power cables. The analysis shows that the IEC 60287-1-1 standard overestimates the armour losses which lead...... to the installation of cables with excessive phase conductor cross section. This paper also presents an example of the potential economic benefits of having a better knowledge of the losses introduced by the armour.......The number of offshore wind farms will keep increasing in the future as a part of the shift towards a CO2 free energy production. The energy harvested from the wind farm must be brought to shore, which is often done by using a three-phase armoured submarine power cable. The use of an armour...

  9. What threat do turbidity currents and submarine landslides pose to submarine telecommunications cable infrastructure? (United States)

    Clare, Michael; Pope, Edward; Talling, Peter; Hunt, James; Carter, Lionel


    The global economy relies on uninterrupted usage of a network of telecommunication cables on the seafloor. These submarine cables carry ~99% of all trans-oceanic digital data and voice communications traffic worldwide, as they have far greater bandwidth than satellites. Over 9 million SWIFT banks transfers alone were made using these cables in 2004, totalling 7.4 trillion of transactions per day between 208 countries, which grew to 15 million SWIFT bank transactions last year. We outline the challenge of why, how often, and where seafloor cables are broken by natural causes; primarily subsea landslides and sediment flows (turbidity currents and also debris flows and hyperpycnal flows). These slides and flows can be very destructive. As an example, a sediment flow in 1929 travelled up to 19 m/s and broke 11 cables in the NE Atlantic, running out for ~800 km to the abyssal ocean. The 2006 Pingtung earthquake triggered a sediment flow that broke 22 cables offshore Taiwan over a distance of 450 km. Here, we present initial results from the first statistical analysis of a global database of cable breaks and causes. We first investigate the controls on frequency of submarine cable breaks in different environmental and geological settings worldwide. We assess which types of earthquake pose a significant threat to submarine cable networks. Meteorological events, such as hurricanes and typhoons, pose a significant threat to submarine cable networks, so we also discuss the potential impacts of future climate change on the frequency of such hazards. We then go on to ask what are the physical impacts of submarine sediment flows on submerged cables? A striking observation from past cable breaks is sometimes cables remain unbroken, whilst adjacent cables are severed (and record powerful flows travelling at up to 6 m/s). Why are some cables broken, but neighbouring cables remain intact? We provide some explanations for this question, and outline the need for future in

  10. Potential Impact of Submarine Power Cables on Crab Harvest (United States)

    Bull, A. S.; Nishimoto, M.


    Offshore renewable energy installations convert wave or wind energy to electricity and transfer the power to shore through transmission cables laid on or buried beneath the seafloor. West coast commercial fishermen, who harvest the highly prized Dungeness crab (Metacarcinus magister) and the rock crab (Cancer spp.), are concerned that the interface of crabs and electromagnetic fields (EMF) from these cables will present an electrified fence on the seafloor that their target resource will not cross. Combined with the assistance of professional fishermen, submarine transmission cables that electrify island communities and offshore oil platforms in the eastern Pacific provide an opportunity to test the harvest of crab species across power transmission cables. In situ field techniques give commercial crab species a choice to decide if they will cross fully energized, EMF emitting, power transmission cables, in response to baited traps. Each independent trial is either one of two possible responses: the crab crosses the cable to enter a trap (1) or the crab does not cross the cable to enter a trap (0). Conditions vary among sample units by the following categorical, fixed factors (i.e., covariates) of cable structure (buried or unburied); direction of cable from crab position (west or east, north or south); time and season. A generalized linear model is fit to the data to determine whether any of these factors affect the probability of crabs crossing an energized cable to enter baited traps. Additionally, the experimental design, aside from the number of runs (set of sample trials) and the dates of the runs, is the same in the Santa Barbara Channel for rock crab and Puget Sound for Dungeness crab, and allows us to compare the capture rates of the two species in the two areas. We present preliminary results from field testing in 2015.

  11. Micro-tunneling as an alternative to submarine cable

    Energy Technology Data Exchange (ETDEWEB)

    Russo, D.A. [Seattle City Light, WA (United States); Hansen, D. [CH2M Hill, Bellevue, WA (United States)


    The geography that gives Seattle its beauty can pose unique challenges for the engineers attempting to provide service to the customers who live near or upon these features. Steep, wooded hills and greenbelts create familiar problems of construction and right-of-way maintenance. The waterways and adjoining shoreline zones present a more difficult set of requirements. When Seattle City Light determined it was necessary to install 2-26 KV feeders across the Salmon Bay waterway, they discovered that submarine cables could not be used. Shallow angle directional drilling and micro-tunneling were examined and it was fond that a microtunneled duct bank was the best method to use.

  12. Development of an underwater ROV system for submarine cable maintenance. Kaitei cable maintenance yo suichu robot no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Iyama, T.; Takahashi, Y.; Kaya, F.; Shigemitsu, T. (Ishikawajima-Harima Heavy Industries, Co. Ltd., Tokyo (Japan))


    For the purpose of repairing, burying, and inspecting submarine telecommunication cables more speedily and at greater depth than conventional processes, an underwater remotely operated robot system for submarine cable maintenance has been developed. The system is composed of an underwater remotely operated vehicle (ROV), tether cables, a tether management system, umbilical cables, a launch and recovery system, control units, and electric power units. The ROV is loaded with thrusters for propulsion, a television camera, a cable location system, manipulators, a cable gripper/cutter unit, a cable burier/digger unit, a variable ballast unit, various sensors, et al. Since its entrance into service in October, 1989, the system has been successfully operated in various sea areas around Japan with a crew of three or four for operation and maintenance. This paper describes the outline of the system configuration and their specifications. 12 figs., 1 tab.

  13. Volume transport data from a submarine cable in the Florida Strait in 2014 (NODC Accession 0125429) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean and raw voltage volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in...

  14. Understanding losses in three core armoured submarine cables

    DEFF Research Database (Denmark)

    Silva, Filipe Miguel Faria da; Ebdrup, Thomas; Bak, Claus Leth


    As the number of offshore wind farms increases so does the number of array cables. The array cables are used to interconnect the wind turbines in a wind farm and to connect the wind farm to a collector platform, whereas the connection to shore is performed by means of a HV transmission cable. For...

  15. Assessing potential impacts of energized submarine power cables on crab harvests (United States)

    Love, Milton S.; Nishimoto, Mary M.; Clark, Scott; McCrea, Merit; Bull, Ann Scarborough


    Offshore renewable energy facilities transmit electricity to shore through submarine power cables. Electromagnetic field emissions (EMFs) are generated from the transmission of electricity through these cables, such as the AC inter-array (between unit) and AC export (to shore) cables often used in offshore energy production. The EMF has both an electric component and a magnetic component. While sheathing can block the direct electric field, the magnetic field is not blocked. A concern raised by fishermen on the Pacific Coast of North America is that commercially important Dungeness crab (Metacarcinus magister Dana, 1852)) might not cross over an energized submarine power cable to enter a baited crab trap, thus potentially reducing their catch. The presence of operating energized cables off southern California and in Puget Sound (cables that are comparable to those within the arrays of existing offshore wind energy devices) allowed us to conduct experiments on how energized power cables might affect the harvesting of both M. magister and another commercially important crab species, Cancer productus Randall, 1839. In this study we tested the questions: 1) Is the catchability of crabs reduced if these animals must traverse an energized power cable to enter a trap and 2) if crabs preferentially do not cross an energized cable, is it the cable structure or the EMF emitted from that cable that deters crabs from crossing? In field experiments off southern California and in Puget Sound, crabs were given a choice of walking over an energized power cable to a baited trap or walking directly away from that cable to a second baited trap. Based on our research we found no evidence that the EMF emitted by energized submarine power cables influenced the catchability of these two species of commercially important crabs. In addition, there was no difference in the crabs' responses to lightly buried versus unburied cables. We did observe that, regardless of the position of the cable

  16. Contributions for the modelling of submarine cables – current density and simplified modelling of wired layers

    DEFF Research Database (Denmark)

    Silva, Filipe Miguel Faria da; Bak, Claus Leth; Ebdrup, Thomas


    This article researches two topics relevant for the development of accurate formulae able to estimate the ampacity of HVAC submarine cables. Simplified formulae for estimating the current density distribution, which can be used for theoretical analyses, are developed and compared with the exact...

  17. Effects of submarine power transmission cables on a glass sponge reef and associated megafaunal community. (United States)

    Dunham, A; Pegg, J R; Carolsfeld, W; Davies, S; Murfitt, I; Boutillier, J


    We examined the effects of submarine power transmission cable installation and operation on glass sponge reef condition and associated megafauna. Video and still imagery were collected using a Remotely Operated Vehicle twice a year for 4 years following cable installation. The effects of cables on glass sponges were assessed by comparing sponge cover along fixed transects and at marked index sites. Megafauna counts along transects were used to explore the effects on associated community. We found no evidence of cable movement across the sponge reef surface. Live sponge cover was found to be consistently lower along cable transects and at cable index sites compared to controls. Live sponge cover was the lowest (55 ± 1.1% decrease) at cable index sites 1.5 years after installation and recovered to 85 ± 30.6% of the original size over the following 2 years. Our data suggest 100% glass sponge mortality along the direct cable footprint and 15% mortality in the surrounding 1.5 m corridor 3.5 years after cable installation. Growth rate of a new glass sponge was 1 and 3 cm/year in first and second year, respectively, and appeared to be seasonal. We observed a diverse megafaunal community with representatives from 7 phyla and 14 classes. Total megafauna, spot prawn, and other Arthropoda abundances were slightly lower along cable transects although the effect of cable presence was not statistically significant. The following measures could be taken to reduce the amount of damage to glass sponge reefs and associated fauna: routing the cable around reefs, whenever possible, minimizing cable movement across the surface of the reef at installation and routine operation, and assessing potential damage to glass sponges prior to decommissioning. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  18. Volume transport data from a submarine cable in the Florida Strait from 1982 to 1998 (NODC Accession 0087879) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in the Florida Strait...

  19. MVAC Submarine cable, magnetic fields measurements and analysis

    DEFF Research Database (Denmark)

    Expethit, Adrian; Sørensen, Sebastian Bille; Arentsen, Martin Trolle


    to measure how the magnetic field varies between wires, above a wire, inside the wire arrangement and at sections without armour. The magnetic field tests are compared to a COMSOL model of the specified cable showing good compliance between experimental and simulated results. It is concluded that at low core...

  20. Insulation coordination for lightning overvoltages on a long HVDC submarine cable

    Energy Technology Data Exchange (ETDEWEB)

    Mader, D.J.


    This paper demonstrates by detailed modelling and simulation a statistical approach to determining the lightning-induced overvoltage stresses on the insulation of a 220 km HVDC submarine cable due to lightning strikes to the overhead line, and explores methods of controlling these overvoltages to levels that will allow lightning impulse withstand levels as low as 2.0 per unit of working voltage with an adequate safety margin.

  1. Proposal for using commercial submarine telecommunications cables for monitoring earthquakes and tsunamis - the SMART cable concept (United States)

    Tilmann, Frederik; Howe, Bruce; Butler, Rhett; Strollo, Angelo; Weinstein, Stuart


    Hundreds of thousands of kilometres of commercial telecommunications cables traverse the world's oceans, many of them crossing large ocean basins, which are otherwise poorly sampled by geophysical sensors (seismometers or pressure gauges), or running along active continental margins, where additional observations would be particularly valuable for allowing observation of subduction zone earthquakes and offshore plate deformation from the updip end. However, as of today these cables are unaware of their environment. These cables are equipped with repeaters spaced at 50 km intervals to boost the telecom signal, though. These repeaters in principle offer access to power and bandwidth, providing the opportunity to add sensor capability to future "SMART" cables (Science Monitoring and Reliable Telecommunications). In a workshop held in early November 2016 at the German Research Centre for Geosciences in Potsdam (GFZ) research scientists, practitioners from earthquake observatories and tsunami warning centers, and engineers discussed possible applications of such SMART cables both from the viewpoint of fundamental research, i.e. Earth imaging and the study of earthquake processes and possibly plate deformation, as well as technical aspects of possible implementations by drawing on the expertise of operators of existing cabled networks. In this presentation, we will summarise the outcomes of this workshop.

  2. 'Green' Submarine Cable Systems for Ocean/Climate Monitoring and Disaster Warning (United States)

    Barnes, C. R.; Butler, R.; Howe, B. M.; Bueti, M. C.


    A recent joint initiative between three UN agencies is proposing to develop trans-ocean mini-observatories to measure changing seafloor ocean observables. A Joint Task Force (JTF), established in 2012 by the International Telecommunication Union (ITU), the World Meteorological Organization (WMO) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO, is examining novel uses for submarine telecommunication cables. With ITU secretariat support, the JTF is developing a strategy and roadmap that could lead to enabling the availability of modified 'green' submarine cable systems equipped with scientific sensors (such as temperature, pressure and acceleration) for climate monitoring and disaster risk reduction (particularly tsunamis). If successful and needing support from industry and regulatory bodies, a wide network of mini-observatories could be established at many places across the world's ocean floors to measure these important parameters accurately over several decades. The initiative addresses two main issues: a) the need for sustained climate-quality data from the sparsely observed deep oceans and continental slopes but extending into coastal waters; and b) the desire to increase the reliability and integrity of the global tsunami warning networks. Presently, plans are being developed to launch a pilot project with the active involvement of cable industry players and existing ocean observatory researchers.

  3. Analytical Expression of Equivalent Transverse Magnetic Permeability for Three-core Wire Armoured Submarine Cables

    DEFF Research Database (Denmark)

    Viafora, Nicola; Baù, Matteo; Dall, Laurits Bergholdt


    As three-core wire-armoured submarine cables become progressively more relevant, the need for refined modelling techniques grows likewise. IEC Standard 60287 indications though are still widely recognized to be insufficiently accurate, since several effects due to the presence of the collective...... of a simplified yet effective formulation. Such analytical approach is tested in a 2D FEM environment in terms of power losses distribution and compared both to the IEC indications and to an existing formula in the literature. It is found that the values of permeability proposed by the IEC Standard underestimate...... the induced sheath power losses due to the presence of the armour, whereas the proposed approach improves the accuracy, as the magnetic flux density enhancement within the cable is accounted for....

  4. Remarks about the apparent increasing of the drag coefficient on flexible submarine cables

    Energy Technology Data Exchange (ETDEWEB)

    Marichal, D. [Ecole Centrale de Nantes, 44 (France)


    A lot of elongated flexible underwater structures (towing and mooring cables, trawl lines, oil risers...) are used in exploitation of sea resources. All theoretical calculations require to know the hydrodynamic forces acting on these structures (especially the drag coefficient). It was usually assumed that the drag coefficient of a cylindrical element is a constant and takes the value of 1.2 as a rigid cylinder at the typical Reynolds numbers. But, if the cylindrical structure has transverse vibrations - as it is usual for submarine cables -, an important increase of the drag coefficient seems to appear Our purpose is to show that the first explanation of the drag coefficient increase comes partly from the problem formulation. It is usual to think that the towing speed is very important compared with the transverse motion velocity. But, in fact, the drag results in the combination of the normal component of the flow and this transverse motion velocity. (author)

  5. Installation of XLPE-Insulated 400 kV Submarine AC Power Cables under the Dardanelles Strait: A 4 GW Turkish Grid Reinforcement

    Directory of Open Access Journals (Sweden)

    Roberto Benato


    Full Text Available This paper describes the 400 kV AC submarine link under the Dardanelles Strait composed of 12 submarine armoured single-core cross-linked polyethylene (XLPE-insulated cables (plus a back-up power cable. The link consists of two parallel-operated double-circuit links named Lâpseki–Sütlüce I and Lâpseki–Sütlüce II. The transmissible power is 4000 MW (1000 MW per circuit and the average length for a single-core cable is about 4.6 km: the submarine cables are part of overhead lines. This paper gives a wide account of the cable installations and, chiefly, of the cable protections on the seabed: different protection choices were extensively used (i.e., water jetting and mattressing.

  6. An Experimental Multi-disciplinary observatory (VENUS at the Ryukyu Trench using the Guam-Okinawa Geophysical Submarine Cable

    Directory of Open Access Journals (Sweden)

    Y. Shirasaki


    Full Text Available A multidisciplinary Ocean Bottom Observatory (MDOBO was installed on VENUS (Versatile Eco-monitoring Network by Undersea-cable System a depth of 2,170 meters on the slope of the Ryukyu Trench. In this context, “Eco-“ refers to both economic (e.g., earthquake hazard mitigation and ecological motivation. The first step in this instillation was to insert a telemetry/power system into the submarine coaxial cable; this system could then service the MODOBO, which consist of seven major bottom sensor packages. During August-September 1999, using a deep-towed unit and both manned and unmanned submersibles coupled with precise ship navigation, the MDOBO system and its attendant cables were deployed over a range of distances from 80 m to 1 km from the telemetry system, with several meter allowance for navigational uncertainty in positioning. The unmanned submersible then extended the multi-conductor extension cables from the instrument units toward the telemetry system and connected them to undersea mateable connectors on a junction box installed on the submarine cable. The MDOBO collected one and half months of continuous records. Several kinds of useful data were collected after installation, including an aftershock (Ms=6.1 of the 1999 Chi-Chi earthquake (Ms=7.7 in Taiwan.

  7. Submarine fiber cable network systems cost planning considerations with achieved high transmission capacity and signal quality enhancement (United States)

    Rashed, Ahmed Nabih Zaki


    This paper has presented theoretically the comparison between three types of fibers which are investigated extensively: plastic clad silica (PCS), polystyrene (PS) and perfluorinated graded index polymer optical fibers (PF GI-POF) for high speed undersea cable systems. Based on experimental data, both the deep ocean water temperature and pressure are tailored as functions of the water depth. It is taken into account the estimation of the total cost of the submarine fiber cable system for transmission techniques under study. The system capacity as well as the spectral losses, and the dispersion effects are parametrically investigated over wide range ranges of the set of affecting parameters {wavelength, ocean depth (and consequently the ocean pressure and temperature), and the chemical structure}. The results show that PCS has the optimum performance in compared with other fibers. Therefore PCS fiber is the most appropriate candidate among all types of fibers for high speed local submarine communication systems.

  8. Installation and operational effects of a HVDC submarine cable in a continental shelf setting: Bass Strait, Australia

    Directory of Open Access Journals (Sweden)

    John Sherwood


    Full Text Available Despite the many submarine telecommunications and power cables laid world-wide there are fewer than ten published studies of their environmental effects in the refereed literature. This paper describes an investigation into the effects of laying and operating the Basslink High Voltage Direct Current (HVDC cable and its associated metallic return cable across Bass Strait in South East Australia. Over more than 95% of its length the cable was directly laid into a wet jetted trench given the predominantly soft sediments encountered. Underwater remote video investigations found that within two years all visible evidence of the cable and trench was gone at over a third of the transects at six deep water sites (32–72m deep. At other deep water transects the residual trench trapped drift material providing habitat for the generally sparsely distributed benthic community. Diver surveys at both of the near shore sites (<15m deep on the northern side of the Strait also found the cable route was undetectable after a year. On the southern side, where the cable traversed hard basalt rock near shore, it was encased in a protective cast iron half shell. Ecological studies by divers over 3.5 years demonstrated the colonization of the hard shell by similar species occupying hard substrates elsewhere on the basalt reef. Magnetic field strengths associated with the operating cable were found to be within 0.8% of those predicted from theory with strength dropping rapidly with distance from the cable. Beyond 20m the field was indistinguishable from background.

  9. A Comparison of Fishes and Invertebrates Living in the Vicinity of Energized and Unenergized Submarine Power Cables and Natural Sea Floor off Southern California, USA

    Directory of Open Access Journals (Sweden)

    Milton S. Love


    Full Text Available Increasing reliance on deep-water renewable energy has increased concerns about the effects of the electromagnetic fields (EMFs generated by submarine power cables on aquatic organisms. Off southern California, we conducted surveys of marine organisms living around energized and unenergized submarine power cables and nearby sea floor during 2012–2014 at depths between 76 and 213 m. In general, EMFs declined to background levels about one meter from the cable. We found no statistical difference in species composition between the fish assemblages along the energized and unenergized cables. The natural habitat community statistically differed from both energized and unenergized cable communities. Within species (or species groups, we found no differences in densities between energized and unenergized cables. Total fish densities were significantly higher around the cables than over the natural habitat. We found that invertebrate communities were structured by habitat type and depth and, similar to the fishes, there was no statistical difference between the energized and unenergized cables. Individually, the densities of four invertebrate species or species groups (Metridium farcimen, Luidia spp., unidentified black Crinoidea, and Urticina spp. differed between energized and unenergized cables, but this difference was not significant across all depth strata. The invertebrate community inhabiting the natural habitat strongly differed from the energized and unenergized cable community exhibiting the fewest species and individuals.

  10. Cable Capacitance Attack against the KLJN Secure Key Exchange

    Directory of Open Access Journals (Sweden)

    Hsien-Pu Chen


    Full Text Available The security of the Kirchhoff-law-Johnson-(like-noise (KLJN key exchange system is based on the fluctuation-dissipation theorem of classical statistical physics. Similarly to quantum key distribution, in practical situations, due to the non-idealities of the building elements, there is a small information leak, which can be mitigated by privacy amplification or other techniques so that unconditional (information-theoretic security is preserved. In this paper, the industrial cable and circuit simulator LTSPICE is used to validate the information leak due to one of the non-idealities in KLJN, the parasitic (cable capacitance. Simulation results show that privacy amplification and/or capacitor killer (capacitance compensation arrangements can effectively eliminate the leak.

  11. 77 FR 59749 - Safety Zone; Submarine Cable Installation Project; Chicago River, Chicago, IL (United States)


    ... collisions between contractors and vessel traffic, and the striking of keels and propellers against cable... Subjects in 33 CFR Part 165 Harbors, Marine safety, Navigation (water), Reporting and recordkeeping...

  12. The Protection of Undersea Cables: A Global Security Threat (United States)


    10 Samuel Morse demonstrated “ Morse Code” in 1844 and patented the design in 1850. The first undersea ( telegraph ) cable was laid between England... telegraph cable linked London with the new world, via Newfoundland.2 The 143 words transmitted in 10 hours, replaced a one-way dispatch that would...Cable History The history of undersea cables started in 1795 when a Spaniard named Salva suggested the idea of underwater telegraphic communication

  13. Raman amplification in an optically high-powered data link dedicated to a 10 km long extension for submarine cabled observatories (United States)

    Audo, F.; Perhirin, S.; Quintard, V.; Guegan, M.; Perennou, A.; Auffret, Y.


    We describe a quasi-all-optical extension dedicated to simplifying the deployment of submarine cabled observatories. Based on power-over-fiber technologies, high power supply and data are both transmitted in one optical fiber of a few kilometers in length. We study the Raman amplification on the down- and up-stream data in the static regime with the high optical power varying from 100 mW to 4 W over a 10 km long single-mode optical fiber. We focus on the data optical budget and signal to noise ratio dependence with respect to the high optical power value and the data optical wavelength. We also present the transmission quality in the dynamic regime of this quasi-all-optical extension.

  14. Trial of Multidisciplinary Observation at an Expandable Sub-Marine Cabled Station “Off-Hatsushima Island Observatory” in Sagami Bay, Japan

    Directory of Open Access Journals (Sweden)

    Toshiyasu Nagao


    Full Text Available Sagami Bay is an active tectonic area in Japan. In 1993, a real-time deep sea floor observatory was deployed at 1,175 m depth about 7 km off Hatsushima Island, Sagami Bay to monitor seismic activities and other geophysical phenomena. Video cameras monitored biological activities associated with tectonic activities. The observation system was renovated completely in 2000. An ocean bottom electromagnetic meter (OBEM, an ocean bottom differential pressure gauge (DPG system, and an ocean bottom gravity meter (OBG were installed January 2005; operations began in February of that year. An earthquake (M5.4 in April 2006, generated a submarine landslide that reached the Hatsushima Observatory, moving some sensors. The video camera took movies of mudflows; OBEM and other sensors detected distinctive changes occurring with the mudflow. Although the DPG and OBG were recovered in January 2008, the OBEM continues to obtain data.

  15. Steady State Modelling of Three-core Wire Armoured Submarine Cables: Power losses and Ampacity Estimation based on FEM and IEC

    DEFF Research Database (Denmark)

    Baù, Matteo; Viafora, Nicola; Hansen, Chris Skovgaard


    in a comparative study with the IEC 60287 Standard, developed in terms of power losses, loss factors and cable ampacity. Despite the model limitations, the estimated loss factors are mainly in compliance with the state of the art, verifying the widely recognized conservatism of the IEC standard. Simulation results...... confirm that the wire armour stranding is not accounted for, but also suggest that the ampacity underrating might be due to other inaccuracies in the IEC modelling indications. Overall, the difference in terms of current rating between the FEM and the IEC approach is found to be voltage dependent and more...

  16. Random Vibration and Torque Tests of Fasteners Secured With Locking Cable, Room Temperature Vulcanized (RTV) Rubber, and Closed Cell Foam to Support the Launch of STS-82 (United States)

    Yost, V. H.


    During a walkdown of the Space Transportation System (STS) orbiter for the 82nd Space Shuttle flight (STS-82), technicians found several safety cables for bolts with missing or loose ferrules. Typically, two or three bolts are secured with a cable which passes through one of the holes in the head of each bolt and a ferrule is crimped on each end of the cable to prevent it from coming out of the holes. The purpose of the cable is to prevent bolts from rotating should they become untightened. Other bolts are secured with either a locking cable or wire which is covered with RTV and foam. The RTV and foam would have to be removed to inspect for missing or loose ferrules. To determine whether this was necessary, vibration and torque test fixtures and tests were made to determine whether or not bolts with missing or loose ferrules would unloosen. These tests showed they would not, and the RTV and foam was not removed.

  17. 78 FR 53109 - Security Zones; Naval Base Point Loma; Naval Mine Anti-Submarine Warfare Command; San Diego Bay... (United States)


    ... at Naval Base Point Loma to support the construction of a new Naval fuel pier. In addition to the... security zone for the Naval Base Point Loma Fuel Pier construction and the establishment of a security zone... program during the construction phase of the new fuel pier. The extended security zone at Naval Base Point...

  18. Submarine hydrodynamics

    CERN Document Server

    Renilson, Martin


    This book adopts a practical approach and presents recent research together with applications in real submarine design and operation. Topics covered include hydrostatics, manoeuvring, resistance and propulsion of submarines. The author briefly reviews basic concepts in ship hydrodynamics and goes on to show how they are applied to submarines, including a look at the use of physical model experiments. The issues associated with manoeuvring in both the horizontal and vertical planes are explained, and readers will discover suggested criteria for stability, along with rudder and hydroplane effectiveness. The book includes a section on appendage design which includes information on sail design, different arrangements of bow planes and alternative stern configurations. Other themes explored in this book include hydro-acoustic performance, the components of resistance and the effect of hull shape. Readers will value the author’s applied experience as well as the empirical expressions that are presented for use a...

  19. Offshore Cable Installation - Lillgrund. Lillgrund Pilot Project

    Energy Technology Data Exchange (ETDEWEB)

    Unosson, Oscar (Vattenfall Vindkraft AB, Stockholm (Sweden))


    This report describes the installation method and the experiences gained during the installation of the submarine cables for the offshore wind farm at Lillgrund. The wind farm consists of 48 wind turbines and is expected to produce 0.33 TWh annually. Different aspects of the installation, such as techniques, co-operation between the installation teams, weather conditions and regulatory and environmental issues are described in this report. In addition, recommendations and guidelines are provided, which hopefully can be utilised in future offshore wind projects. The trenches, in which the submarine cables were laid, were excavated weeks before the cable laying. This installation technique proved to be successful for the laying of the inter array cables. The export cable, however, was laid into position with difficulty. The main reason why the laying of the export cable proved more challenging was due to practical difficulties connected with the barge entrusted with the cable laying, Nautilus Maxi. The barge ran aground a number of times and it had difficulties with the thrusters, which made it impossible to manoeuvre. When laying the inter array cables, the method specification was closely followed, and the laying of the cables was executed successfully. The knowledge and experience gained from the offshore cable installation in Lillgrund is essential when writing technical specifications for new wind plant projects. It is recommended to avoid offshore cable installation work in winter seasons. That will lower the chances of dealing with bad weather and, in turn, will reduce the risks

  20. Switching studies for the Horns Rev 2 wind farm main cable

    DEFF Research Database (Denmark)

    Jensen, Christian Flytkjær; Faria da Silva, Filipe; Bak, Claus Leth


    sections with a total length of 57.7 km and a 42 km long submarine cable. The submarine cable is a three phase type of cable, and three single conductor cables are used for the land cable. Methods of recalculating the physical cable parameters, given in the data sheet, to parameters suitable for the cable......This article proposes a method of constructing a PSCAD model suitable for switching studies in a system containing long HVAC cables. The transmission network connection to the 215 MW offshore wind farm Horns Rev 2 is used as a case study. The connection to Horns Rev 2 consists of two land cable......, and the use of different cable models....

  1. 78 FR 72025 - Security Zones; Naval Base Point Loma; Naval Mine Anti Submarine Warfare Command; San Diego Bay... (United States)


    ... click ``SEARCH.'' Click on Open Docket Folder on the line associated with this rulemaking. You may also... Pier security zone are bound by the following coordinates: 32 42'28.8'' N, 117 14'13.2'' W 32 42'28.8'' N, 117 14'12.6'' W 32 42'10.2'' N, 117 14'03.0'' W 32 42'06.2'' N, 117 14'01.5'' W 32 41'49.5'' N...

  2. Introduction to the special issue on submarine geohazard records and potential seafloor instability

    Directory of Open Access Journals (Sweden)

    Song-Chuen Chen Jia-Jyun Dong


    Full Text Available Submarine landslides frequently occur in passive continental margins or active margins (Hampton et al. 1996; Wynn et al. 2000; Mienert et al. 2002; Korup et al. 2007; Twichell et al. 2009; Cukur et al. 2016. Submarine landslides have been studied extensively not only for scientific research but also for submarine geohazards. Submarine landslides could jeopardize marine infrastructures, such as offshore drilling platforms or submarine telecommunication cables, and could even trigger disastrous tsunamis (Bondevik et al. 2005; Harbitz et al. 2006; Hornbach et al. 2007, 2008; Hsu et al. 2008; Su et al. 2012; Tappin et al. 2014; Li et al. 2015. For instance, one disastrous tsunami hitting the coastal area of southwestern Taiwan in 1781 or 1782 was reported (Chen 1830; Hsu 1983; the tsunami event was probably generated by submarine landslides in the offshore area of southwestern Taiwan (Li et al. 2015. Moreover, several submarine landslides triggered by the 2006 Pingtung earthquake have induced turbidity currents off southwest Taiwan and destroyed about 14 submarine telecommunication cables off SW Taiwan (Hsu et al. 2008. The area of southwest Taiwan currently has a dense population (more than 3 million people in total, one deep-water Kaohsiung Port, several tanks of liquefied natural gas and a nuclear power plant on the coast (Fig. 1. Numerous submarine telecommunication cables exist off SW Taiwan. If a considerable tsunami event would hit again the costal area of SW Taiwan, the damage could very serious. Likewise, there are two nuclear power plants on the coast of northern Taiwan (Fig. 2, and the population in northern Taiwan has more than 10 million people. Submarine telecommunication cables also exist off northern Taiwan. In any case, it is important to understand the status of seafloor stability in the offshore areas of SW and NE Taiwan. For that, this special issue of submarine geohazard records and potential seafloor instability is aimed to

  3. Superconductor cable (United States)

    Allais, Arnaud; Schmidt, Frank; Marzahn, Erik


    A superconductor cable is described, having a superconductive flexible cable core (1) , which is laid in a cryostat (2, 3, 4), in which the cable core (1) runs in the cryostat (2, 3, 4) in the form of a wave or helix at room temperature.

  4. Safety cutting units - maximum security whole cutting cable under voltage; Sicherheitsschneidanlagen - optimale Sicherheit beim Kabelschneiden unter Spannung

    Energy Technology Data Exchange (ETDEWEB)

    Gaenslein, H.G. [Kabelkonfektionstechnik KKT GmbH, Sonneberg (Germany)


    If operations are carried out on electric installations, it is absolutely necessary to find out if these installations are off circuit in order to guarantee an effective protection against the risks caused by electric current. But sometimes it is difficult to identify if the installations is off circuit because in practice the isolated cable cannot always be pursued up to the place of work and voltage on the cable cannot clearly be ascertained respectively. In the last years in these cases a safety cutting unit has proved in practice successful. (orig.) [Deutsch] Sollen an elektrischen Anlagen Arbeiten durchgefuehrt werden, so ist zunaechst die Spannungsfreiheit festzustellen. Die Ermittlung der Spannungsfreiheit in Kabelanlagen bereitet jedoch nicht selten Schwierigkeiten, da in der Praxis das freigeschaltete Kabel nicht eindeutig bis zur Arbeitsstelle verfolgt bzw. die Spannung an einem Kabel nicht eindeutig festgestellt werden kann. In den letzten Jahren hat sich deshalb fuer derartige Faelle der Einsatz von Sicherheitsschneidanlagen bewaehrt. (orig.)

  5. Elimination of a Second-Law-Attack, and All Cable-Resistance-Based Attacks, in the Kirchhoff-Law-Johnson-Noise (KLJN Secure Key Exchange System

    Directory of Open Access Journals (Sweden)

    Laszlo B. Kish


    Full Text Available We introduce the so far most efficient attack against the Kirchhoff-law-Johnson-noise (KLJN secure key exchange system. This attack utilizes the lack of exact thermal equilibrium in practical applications and is based on cable resistance losses and the fact that the Second Law of Thermodynamics cannot provide full security when such losses are present. The new attack does not challenge the unconditional security of the KLJN scheme, but it puts more stringent demands on the security/privacy enhancing protocol than for any earlier attack. In this paper we present a simple defense protocol to fully eliminate this new attack by increasing the noise-temperature at the side of the smaller resistance value over the noise-temperature at the side with the greater resistance. It is shown that this simple protocol totally removes Eve’s information not only for the new attack but also for the old Bergou-Scheuer-Yariv attack. The presently most efficient attacks against the KLJN scheme are thereby completely nullified.

  6. Submarine Medicine Team (United States)

    Federal Laboratory Consortium — The Submarine Medicine Team conducts basic and applied research on biomedical aspects of submarine and diving environments. It focuses on ways to optimize the health...

  7. Cable compliance (United States)

    Kerley, J.; Eklund, W.; Burkhardt, R.; Rossoni, P.


    The object of the investigation was to solve mechanical problems using cable-in-bending and cable-in-torsion. These problems included robotic contacts, targets, and controls using cable compliance. Studies continued in the use of cable compliance for the handicapped and the elderly. These included work stations, walkers, prosthetic knee joints, elbow joints, and wrist joints. More than half of these objects were met, and models were made and studies completed on most of the others. It was concluded that the many different and versatile solutions obtained only opened the door to many future challenges.

  8. Flat conductor cable for electrical packaging (United States)

    Angele, W.


    Flat conductor cable (FCC) is relatively new, highly promising means for electrical packaging and system integration. FCC offers numerous desirable traits (weight, volume and cost savings, flexibility, high reliability, predictable and repeatable electrical characteristics) which make it extremely attractive as a packaging medium. FCC, today, finds wide application in everything from integration of lunar equipment to the packaging of electronics in nuclear submarines. Described are cable construction and means of termination, applicable specifications and standards, and total FCC systems. A list of additional sources of data is also included for more intensive study.

  9. Assessing Resilience in the Global Undersea Cable Infrastructure (United States)


    Helena, Ascension , and Tristan da Cunha 6,724 143 Vanuatu 5,656 144 Virgin Islands 4,876 145 Papua New Guinea 4,847 146 Micronesia, Federated States... earthquakes , tsunamis, and undersea landslides occur less 9 frequently but typically affect multiple cables. Considering these natural and... earthquake along the southern coast of Taiwan triggered submarine landslides over large areas of the ocean floor and broke nine undersea cables in the

  10. Harmonic modelling, propagation and mitigation for large wind power plants connected via long HVAC cables

    DEFF Research Database (Denmark)

    Dowlatabadi, Mohammadkazem Bakhshizadeh; Hjerrild, Jesper; Kocewiak, Łukasz


    be reduced and operational availability and the reliability can be improved. Challenges hereto include lower resonance frequencies due to the long cables, frequency dependent modelling of long submarine cables, passive filtering, and PLL dynamics in the control loops (from a harmonic stability point of view)....

  11. VT Cable Systems 2005 (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable System dataset (CABLE2005) includes lines depicting the extent of Vermont's cable system as of 12/31/2005. Numerous cable companies...

  12. VT Cable Systems 2007 (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable System dataset (CABLE2007) includes lines depicting the extent of Vermont's cable system as of 12/31/2007. Numerous cable companies...

  13. Low cost submarine robot


    Ponlachart Chotikarn; Werapong Koedsin; Boonlua Phongdara; Pattara Aiyarak


    A submarine robot is a semi-autonomous submarine robot used mainly for marine environmental research. We aim todevelop a low cost, semi-autonomous submarine robot which is able to travel underwater. The robot’s structure was designedand patented using a novel idea of the diving system employing a volume adjustment mechanism to vary the robot’s density.A light weight, flexibility and small structure provided by PVC can be used to construct the torpedo-liked shape robot.Hydraulic seal and O-rin...

  14. Low cost submarine robot

    Directory of Open Access Journals (Sweden)

    Ponlachart Chotikarn


    Full Text Available A submarine robot is a semi-autonomous submarine robot used mainly for marine environmental research. We aim todevelop a low cost, semi-autonomous submarine robot which is able to travel underwater. The robot’s structure was designedand patented using a novel idea of the diving system employing a volume adjustment mechanism to vary the robot’s density.A light weight, flexibility and small structure provided by PVC can be used to construct the torpedo-liked shape robot.Hydraulic seal and O-ring rubbers are used to prevent water leaking. This robot is controlled by a wired communicationsystem.

  15. 46 CFR 111.60-6 - Fiber optic cable. (United States)


    ... 46 Shipping 4 2010-10-01 2010-10-01 false Fiber optic cable. 111.60-6 Section 111.60-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-6 Fiber optic cable. Each fiber optic cable must— (a) Be...

  16. Superconductor cable (United States)

    Smith, Jr., Darrell F.; Lake, Bill L.; Ballinger, Ronald G.


    A superconducting cable comprising an in-situ-formed type II superconductor, e.g. Nb.sub.3 Sn, in association with a stabilizing conductor both in heat transfer relationship with at least one passage adapted to carry liquified gaseous refrigerant. The conductor and said at least one passage are enclosed by a sheath comprising an alloy consisting essentially of about 49% nickel, about 4% chromium, about 3% niobium, about 1.4% titanium, about 1% aluminum, balance essentially iron.

  17. Addressing submarine geohazards through scientific drilling (United States)

    Camerlenghi, A.


    eruptions, earthquakes and the associated tsunamis can lead to destruction of seafloor structures potentially capable of releasing hydrocarbon pollutants into Mediterranean waters, and damage to a dense telecommunication cables net that would cause severe economic loss. However, the most devastating effect would be that of earthquake or landslide-induced tsunamis. When compared to other basins, the Mediterranean has larger vulnerability due to its small dimensions, resulting in close proximity to tsunami sources and impact areas. Recent examples include the 1979 Nice airport submarine landslide and tsunami and the 2002 Stromboli volcano landslide and tsunami. Future international scientific drilling must include submarine geohazards among priority scientific objectives. The science advisory structure must be prepared to receive and evaluate proposal specifically addressing submarine geohazards. The implementing organizations need to be prepared for the technological needs of drilling proposals addressing geohazards. Among the most relevant: geotechnical sampling, down-hole logging at shallow depths below the seafloor, in situ geotechnical and physical measurements, capability of deployment of long-term in situ observatories. Pre-site surveys will often aim at the highest possible resolution, three dimensional imaging of the seafloor ant its sub-surface. Drilling for submarine geohazards is seen as an opportunity of multiplatform drilling, and for Mission Specific drilling in particular. Rather than turning the scientific investigation in a purely engineering exercise, proposals addressing submarine geohazards should offer an opportunity to scientists and engineers to work together to unravel the details of basic geological processes that may turn into catastrophic events.

  18. VT Cable Systems 2013 (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable dataset (CABLE2013) includes lines depicting the extent of Vermont's cable modem broadband system as of 6/30/2013 in addition to...

  19. Submarine Salt Karst Terrains

    Directory of Open Access Journals (Sweden)

    Nico Augustin


    Full Text Available Karst terrains that develop in bodies of rock salt (taken as mainly of halite, NaCl are special not only for developing in one of the most soluble of all rocks, but also for developing in one of the weakest rocks. Salt is so weak that many surface-piercing salt diapirs extrude slow fountains of salt that that gravity spread downslope over deserts on land and over sea floors. Salt fountains in the deserts of Iran are usually so dry that they flow at only a few cm/yr but the few rain storms a decade so soak and weaken them that they surge at dm/day for a few days. We illustrate the only case where the rates at which different parts of one of the many tens of subaerial salt karst terrains in Iran flows downslope constrains the rates at which its subaerial salt karst terrains form. Normal seawater is only 10% saturated in NaCl. It should therefore be sufficiently aggressive to erode karst terrains into exposures of salt on the thousands of known submarine salt extrusions that have flowed or are still flowing over the floors of hundreds of submarine basins worldwide. However, we know of no attempt to constrain the processes that form submarine salt karst terrains on any of these of submarine salt extrusions. As on land, many potential submarine karst terrains are cloaked by clastic and pelagic sediments that are often hundreds of m thick. Nevertheless, detailed geophysical and bathymetric surveys have already mapped likely submarine salt karst terrains in at least the Gulf of Mexico, and the Red Sea. New images of these two areas are offered as clear evidence of submarine salt dissolution due to sinking or rising aggressive fluids. We suggest that repeated 3D surveys of distinctive features (± fixed seismic reflectors of such terrains could measure any downslope salt flow and thus offer an exceptional opportunity to constrain the rates at which submarine salt karst terrains develop. Such rates are of interest to all salt tectonicians and the many


    Directory of Open Access Journals (Sweden)

    Alejandro Gómez

    Full Text Available Los cables musculares o fibras de nitinol presentan una excelente alternativa a los actuadores convencionales, con una fuerza de actuación muy alta, equivalente a la de los actuadores hidráulicos, proporcionalmente a su peso, además de su acción silenciosa. Este material, inventado en 1963, aún no es muy conocido y de ahí que se haya realizado una recopilación de sus propiedades. Entre ellas, la temperatura de transición es la más importante, por ser la que activa la aleación. Muchos sistemas se han creado para alcanzar adecuadamente la temperatura de transición, y también se continúa en la investigación de métodos que ayuden a lograr un control preciso del movimiento de la aleación con memoria de forma (SMA.

  1. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...... to quantify the different structural configurations and allows a preliminary optimization of the main structure.Included are the most recent advances in structural design, corrosion protection of cables, aerodynamic safety, and erection procedures....

  2. Molds for cable dielectrics (United States)

    Roose, L.D.


    Molds for use in making end moldings for high-voltage cables are described wherein the dielectric insulator of a cable is heated and molded to conform to a desired shape. As a consequence, high quality substantially bubble-free cable connectors suitable for mating to premanufactured fittings are made. 5 figs.

  3. “Hello, HELLO! Anyone there? - on the need to assess the tsunami risk to global submarine telecommunications infrastructure (United States)

    Dominey-Howes, D.; Goff, J. R.


    National economies are increasingly dependent on the global telecommunications system - and in particular, its submarine cable infrastructure. Submarine cable traffic represents about 30% of global GDP so the cost of losing, or even simply slowing, communications traffic is high. Many natural hazards are capable of damaging and destroying this infrastructure but tsunamis are the most significant threat, particularly in waters >1000 m deep. Submarine cables and their shore-based infrastructure (the anchor points), are at risk from direct and indirect tsunami-related effects. During the 2004 Indian Ocean Tsunami in India and Indonesia, cables were broken (direct effect) as the tsunami eroded supporting sediments, and were further damaged by floating/submerged objects and intense nearshore currents. Shore-based infrastructure was also directly damaged in India, Indonesia, and the Maldives. The 1929 Grand Banks earthquake generated a submarine landslide and tsunami off Newfoundland which broke 12 submarine telegraph cables. In 2006, an earthquake in Taiwan generated submarine landslides and a tsunami. These landslides caused one of the largest disruptions of modern telecommunications history when nine cables in the Strait of Luzon were broken disabling vital connections between SE Asia and the rest of the world. Although electronic traffic in and out of Australia was slowed, it did not cease because >70% of our traffic is routed via cables that pass through Hawaii. This is extremely significant because Hawaii is an internationally recognised bottleneck or “choke point” in the global telecommunications network. The fact that Hawaii is a choke point is important because it is regularly affected by numerous large magnitude natural hazards. Any damage to the submarine telecommunications infrastructure routed through Hawaii could result in significant impacts on the electronic flow of data and voice traffic, negatively affecting dependent economies such as Australia

  4. Cable Aerodynamic Control

    DEFF Research Database (Denmark)

    Kleissl, Kenneth

    This dissertation investigates the possibility of preventing wind-induced cable vibrations on cable-stayed bridges using passive aerodynamic means in the form of cable surface modifications. Especially the phenomenon of rainwind induced vibrations, which is known as the most common type of these ......This dissertation investigates the possibility of preventing wind-induced cable vibrations on cable-stayed bridges using passive aerodynamic means in the form of cable surface modifications. Especially the phenomenon of rainwind induced vibrations, which is known as the most common type...... to a categorization of the different control technics together with an identification of two key mechanisms for reduction of the design drag force. During this project extensive experimental work examining the aerodynamics of the currently used cable surface modifications together with new innovative proposals have...

  5. 37 CFR 201.17 - Statements of Account covering compulsory licenses for secondary transmissions by cable systems. (United States)


    ... charges for security, alarm or facsimile services, charges for late payments, or charges for pay cable or... apartment house) which is charged by the cable system for the basic service of providing secondary...

  6. 20,000 In League Under the Sea: Anonymous Communication, Trust, MLATs, and Undersea Cables

    Directory of Open Access Journals (Sweden)

    Jaggard Aaron D.


    Full Text Available Motivated by the effectiveness of correlation attacks against Tor, the censorship arms race, and observations of malicious relays in Tor, we propose that Tor users capture their trust in network elements using probability distributions over the sets of elements observed by network adversaries. We present a modular system that allows users to efficiently and conveniently create such distributions and use them to improve their security. To illustrate this system, we present two novel types of adversaries. First, we study a powerful, pervasive adversary that can compromise an unknown number of Autonomous System organizations, Internet Exchange Point organizations, and Tor relay families. Second, we initiate the study of how an adversary might use Mutual Legal Assistance Treaties (MLATs to enact surveillance. As part of this, we identify submarine cables as a potential subject of trust and incorporate data about these into our MLAT analysis by using them as a proxy for adversary power. Finally, we present preliminary experimental results that show the potential for our trust framework to be used by Tor clients and services to improve security.

  7. SCICEX: Submarine Arctic Science Program (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Submarine Arctic Science Program, SCICEX, is a federal interagency collaboration among the operational Navy, research agencies, and the marine research community...

  8. The Submarine, 1776-1918

    National Research Council Canada - National Science Library

    Uhlig, Frank


    When, on 11 April 1900, the U.S. Navy thought the Holland, named for its designer, that little submarine joined a fleet consisting of two armored cruisers, six monitors, seven first and second-class battleships, and seventeen each...

  9. Cable Tester Box (United States)

    Lee, Jason H.


    Cables are very important electrical devices that carry power and signals across multiple instruments. Any fault in a cable can easily result in a catastrophic outcome. Therefore, verifying that all cables are built to spec is a very important part of Electrical Integration Procedures. Currently, there are two methods used in lab for verifying cable connectivity. (1) Using a Break-Out Box and an ohmmeter this method is time-consuming but effective for custom cables and (2) Commercial Automated Cable Tester Boxes this method is fast, but to test custom cables often requires pre-programmed configuration files, and cables used on spacecraft are often uniquely designed for specific purposes. The idea is to develop a semi-automatic continuity tester that reduces human effort in cable testing, speeds up the electrical integration process, and ensures system safety. The JPL-Cable Tester Box is developed to check every single possible electrical connection in a cable in parallel. This system indicates connectivity through LED (light emitting diode) circuits. Users can choose to test any pin/shell (test node) with a single push of a button, and any other nodes that are shorted to the test node, even if they are in the same connector, will light up with the test node. The JPL-Cable Tester Boxes offers the following advantages: 1. Easy to use: The architecture is simple enough that it only takes 5 minutes for anyone to learn how operate the Cable Tester Box. No pre-programming and calibration are required, since this box only checks continuity. 2. Fast: The cable tester box checks all the possible electrical connections in parallel at a push of a button. If a cable normally takes half an hour to test, using the Cable Tester Box will improve the speed to as little as 60 seconds to complete. 3. Versatile: Multiple cable tester boxes can be used together. As long as all the boxes share the same electrical potential, any number of connectors can be tested together.

  10. Optical Cable Design (United States)

    Aggarwal, I. D.


    Optical cable applications can be divided into four major market segments. These are telecommunication, data, video and military communication. For the majority of the telecommunication, data, and video applications, a loose tube or loose ribbon design can be manufactured without incurring a microbending loss penalty. Fibre performance in the loose tube cables can be maximized by optimizing the lay length, tube dimension and pitch diameter. At present, high quality cables using both single and multimode fibre are being manufactured in volume with no additional microbending loss. For example, single and multimode cables with loss of 0.5 dB/km 1300 nm and very high bandwidths or low dispersion have been successfully installed in many cities. An example of this cable is shown in Figure 1. These cables have been used for direct buried, duct system, aerial or underwater installations.

  11. Cable suspended windmill (United States)

    Farmer, Moses G. (Inventor)


    A windmill is disclosed which includes an airframe having an upwind end and a downwind end. The first rotor is rotatably connected to the airframe, and a generator is supported by the airframe and driven by the rotor. The airframe is supported vertically in an elevated disposition by poles which extend vertically upwardly from the ground and support cables which extend between the vertical poles. Suspension cables suspend the airframe from the support cable.

  12. Turbidity Currents, Submarine Landslides and the 2006 Pingtung Earthquake off SW Taiwan

    Directory of Open Access Journals (Sweden)

    Shu-Kun Hsu


    Full Text Available Submarine landslides or slumps may generate turbidity currents consisting of mixture of sediment and water. Large and fast-moving turbidity currents can incise and erode continental margins and cause damage to artificial structures such as telecommunication cables on the seafloor. In this study, we report that eleven submarine cables across the Kaoping canyon and Manila trench were broken in sequence from 1500 to 4000 m deep, as a consequence of submarine landslides and turbidity currents associated with the 2006 Pingtung earthquakes offshore SW Taiwan. We have established a full-scale scenario and calculation of the turbidity currents along the Kaoping canyon channel from the middle continental slope to the adjacent deep ocean. Our results show that turbidity current velocities vary downstream ranging from 20 to 3.7 and 5.7 m/s, which demonstrates a positive relationship between turbidity current velocity and bathymetric slope. The violent cable failures happened in this case evidenced the destructive power of the turbidity current to seafloor or underwater facilities that should not be underestimated.

  13. Electrical power cable engineering

    CERN Document Server

    Thue, William A


    Fully updated, Electrical Power Cable Engineering, Third Edition again concentrates on the remarkably complex design, application, and preparation methods required to terminate and splice cables. This latest addition to the CRC Press Power Engineering series covers cutting-edge methods for design, manufacture, installation, operation, and maintenance of reliable power cable systems. It is based largely on feedback from experienced university lecturers who have taught courses on these very concepts.The book emphasizes methods to optimize vital design and installation of power cables used in the

  14. Submarine Tailings Disposal (STD—A Review

    Directory of Open Access Journals (Sweden)

    Bernhard Dold


    Full Text Available The mining industry is a fundamental industry involved in the development of modern society, but is also the world’s largest waste producer. This role will be enhanced in the future, because ore grades are generally decreasing, thus leading to increases in the waste/metal production ratio. Mine wastes deposited on-land in so-called tailings dams, impoundments or waste-dumps have several associated environmental issues that need to be addressed (e.g., acid mine drainage formation due to sulphide oxidation, geotechnical stability, among others, and social concerns due to land use during mining. The mining industry recognizes these concerns and is searching for waste management alternatives for the future. One option used in the past was the marine shore or shallow submarine deposition of this waste material in some parts of the world. After the occurrence of some severe environmental pollution, today the deposition in the deep sea (under constant reducing conditions is seen as a new, more secure option, due to the general thought that sulphide minerals are geochemically stable under the reduced conditions prevailing in the deep marine environment. This review highlights the mineralogical and geochemical issues (e.g., solubility of sulphides in seawater; reductive dissolution of oxide minerals under reducing conditions, which have to be considered when evaluating whether submarine tailings disposal is a suitable alternative for mine waste.

  15. Cable Diagnostic Focused Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Hartlein, R.A.; Hampton, R.N.


    This report summarizes an extensive effort made to understand how to effectively use the various diagnostic technologies to establish the condition of medium voltage underground cable circuits. These circuits make up an extensive portion of the electric delivery infrastructure in the United States. Much of this infrastructure is old and experiencing unacceptable failure rates. By deploying efficient diagnostic testing programs, electric utilities can replace or repair circuits that are about to fail, providing an optimal approach to improving electric system reliability. This is an intrinsically complex topic. Underground cable systems are not homogeneous. Cable circuits often contain multiple branches with different cable designs and a range of insulation materials. In addition, each insulation material ages differently as a function of time, temperature and operating environment. To complicate matters further, there are a wide variety of diagnostic technologies available for assessing the condition of cable circuits with a diversity of claims about the effectiveness of each approach. As a result, the benefits of deploying cable diagnostic testing programs have been difficult to establish, leading many utilities to avoid the their use altogether. This project was designed to help address these issues. The information provided is the result of a collaborative effort between Georgia Tech NEETRAC staff, Georgia Tech academic faculty, electric utility industry participants, as well as cable system diagnostic testing service providers and test equipment providers. Report topics include: •How cable systems age and fail, •The various technologies available for detecting potential failure sites, •The advantages and disadvantages of different diagnostic technologies, •Different approaches for utilities to employ cable system diagnostics. The primary deliverables of this project are this report, a Cable Diagnostic Handbook (a subset of this report) and an online

  16. Submarine Information Organization and Prioritization and Submarine Officer of the Deck Experience (United States)


    The Submarine Review, 58-64. Shobe, K. (2002, May). Information organization and modeling of the submarine officer of the deck and sonar operator...Technical Report 01Oct00 - 31Sep02 SUBMARINE INFORMATION ORGANIZATION AND PRIORITIZATION AND SUBMARINE OFFICER OF THE DECK EXPERIENCE 51001 1) Katharine K

  17. Automated Cable Preparation for Robotized Stator Cable Winding

    Directory of Open Access Journals (Sweden)

    Erik Hultman


    Full Text Available A method for robotized cable winding of the Uppsala University Wave Energy Converter generator stator has previously been presented and validated. The purpose of this study is to present and validate further developments to the method: automated stand-alone equipment for the preparation of the winding cables. The cable preparation consists of three parts: feeding the cable from a drum, forming the cable end and cutting the cable. Forming and cutting the cable was previously done manually and only small cable drums could be handled. Therefore the robot cell needed to be stopped frequently. The new equipment was tested in an experimental robot stator cable winding setup. Through the experiments, the equipment was validated to be able to perform fully automated and robust cable preparation. Suggestions are also given on how to further develop the equipment with regards to performance, robustness and quality. Hence, this work represents another important step towards demonstrating completely automated robotized stator cable winding.

  18. Enhancing Submarine Operational Relevance: A Leadership Challenge

    National Research Council Canada - National Science Library

    Daigle, Jr, Michael J


    .... This vision of submarine operations must change. As the military continues to shift to operations focused on joint capabilities, the submarine force must break from the closed, protective, and risk averse culture of its past and push forward...

  19. Submarine silicic volcanism: Processes and products

    Digital Repository Service at National Institute of Oceanography (India)

    Kalangutkar, N.G.; Iyer, S.D.

    The occurrence of submarine silicic volcanics is rare at the mid-oceanic ridges, abyssal depths, seamounts and fracture zones. Hydrothermal processes are active in submarine silicic environments and are associated with host ores of Cu, Au, Ag, Pb...

  20. Multistrand superconductor cable (United States)

    Borden, Albert R.


    Improved multistrand Rutherford-type superconductor cable is produced by using strands which are preformed, prior to being wound into the cable, so that each strand has a variable cross section, with successive portions having a substantially round cross section, a transitional oval cross section, a rectangular cross section, a transitional oval cross section, a round cross section and so forth, in repetitive cycles along the length of the strand. The cable is wound and flattened so that the portions of rectangular cross section extend across the two flat sides of the cable at the strand angle. The portions of round cross section are bent at the edges of the flattened cable, so as to extend between the two flat sides. The rectangular portions of the strands slide easily over one another, so as to facilitate flexing and bending of the cable, while also minimizing the possibility of causing damage to the strands by such flexing or bending. Moreover, the improved cable substantially maintains its compactness and cross-sectional shape when the cable is flexed or bent.

  1. MARS: a cabled observatory testbed in Monterey Bay (United States)

    McNutt, M.; Massion, G.; Raybould, K.; Bellingham, J.; Paull, C.


    With funding from the U.S. National Science Foundation and the David and Lucile Packard Foundation, the Monterey Bay Aquarium Research Institute (MBARI) will be installing a deep-sea observatory in Monterey Bay, California, that will serve as a test bed for a future regional-scale cabled observatory. Monterey Bay offers a variety of active processes for scientific inquiry, including a very productive zone of ocean upwelling, a seismically active strand of the San Andreas fault system, cold seeps, and a very dynamic submarine canyon. The MARS (Monterey Accelerated Research System) cable will extend more than 60 km offshore to an instrument node at a depth of approximately 1.2 km. Extension cords can be run by remotely operated vehicles (ROVs) from the cable node up to several kilometers away in order to provide greater flexibility in siting instruments. The observatory will be serviced using ROVs and will serve as a test bed for developing new sensors, instruments systems, experiment protocols, and mobile platforms for which submarine cables will provide power and two-way communications. In addition to serving as a test bed for instrumentation and platforms, the MARS project will demonstrate models for how to operate, service, and manage a community facility of this sort. In cooperation with our outreach partner, the Monterey Bay Aquarium, we will be examining ways to exploit the full potential of deep-sea observatories for student education and public information. We will also be preparing a proposal to the Integrated Ocean Drilling Program (IODP) to provide a nearby drill hole for connecting bore-hole experiments to the MARS cable, thereby accelerating the development of new tools for probing Earth beneath the oceans.

  2. Ocean Observing using SMART subsea telecommunications cable systems (United States)

    Howe, B. M.


    Planning is underway to integrate ocean sensors into SMART subsea cable systems providing basin and ultimately global array coverage within the next decades (SMART: Scientific Monitoring And Reliable Telecommunications). SMART cables will: contribute to the understanding of ocean dynamics and climate; improve knowledge of earthquakes and forecasting of tsunamis; and complement and enhance existing satellite and in-situ observing systems. SMART cables will be a first order addition to the ocean observing system, with unique contributions, strengthening and complementing satellite and in situ systems. Cables spanning the ocean basins with repeaters every ~50 km will host sensors/mini-observatories, providing power and real-time communications. The current global infrastructure of commercial submarine telecommunications cable systems consists of 1 Gm of cable with ~20,000 repeaters (to boost optical signals); the overall system is refreshed and expanded on time scales of 10 - 20 years and individual systems have lifetimes in excess of 25 years. Initial instrumentation of the cables with bottom temperature, pressure and acceleration sensors will provide unique information for monitoring and studying climate change and for improved tsunami and earthquake warning. These systems will be a new highly reliable, long-lived component of the ocean observing system, complementing satellite, float and other in situ platforms and measurements. Several UN agencies, the International Telecommunication Union, the World Meteorological Organization, and the UNESCO Intergovernmental Oceanographic Commission have formed a Joint Task Force to move this concept to fruition (ITU/WMO/IOC JTF; A review of the overall planning effort and two NASA-funded workshops focusing on the ocean circulation and climate is presented. [Funding provided by NASA.

  3. Submarine geothermal resources (United States)

    Williams, D.L.


    Approximately 20% of the earth's heat loss (or 2 ?? 1012 cal/s) is released through 1% of the earth's surface area and takes the form of hydrothermal discharge from young (Pleistocene or younger) rocks adjacent to active seafloor-spreading centers and submarine volcanic areas. This amount is roughly equivalent to man's present gross energy consumption rate. A sub-seafloor geothermal reservoir, to be exploitable under future economic conditions, will have to be hot, porous, permeable, large, shallow, and near an energy-deficient, populated land mass. Furthermore, the energy must be recoverable using technology achievable at a competitive cost and numerous environmental, legal and institutional problems will have to be overcome. The highest-temperature reservoirs should be found adjacent to the zones of the seafloor extension or volcanism that are subject to high sedimentation rates. The relatively impermeable sediments reduce hydrothermal-discharge flow rates, forcing the heat to be either conducted away or released by high-temperature fluids, both of which lead to reservoir temperatures that can exceed 300??C. There is evidence that the oceanic crust is quite permeable and porous and that it was amenable to deep (3-5 km) penetration by seawater at least some time in the early stages of its evolution. Most of the heat escapes far from land, but there are notable exceptions. For example, in parts of the Gulf of California, thermal gradients in the bottom sediments exceed 1??C/m. In the coastal areas of the Gulf of California, where electricity and fresh water are at a premium, this potential resource lies in shallow water (< 200 m) and within sight of land. Other interesting areas include the Sea of Japan, the Sea of Okhotsk and the Andaman Sea along the margins of the western Pacific, the Tyrrhenian Sea west of Italy, and the southern California borderland and west flank of the Juan de Fuca Ridge off the west coast of the United States. Many questions remain to be

  4. Submarine canyons off Madras Coast

    Digital Repository Service at National Institute of Oceanography (India)

    Setty, M.G.A.P.

    Submarine canyons off the coast of Madras, Tamil Nadu, India were studied during cruise of @iINS Kistna@@ as part of the IIOE programme They consist of hill-like projections and V-shaped valleys Their other features are also reported...

  5. Overseas or Submarines?

    DEFF Research Database (Denmark)

    Vestergaard, Morten Hetmar

    The rise of China in recent decades has taken place on an unprecedented scale and at a breathtaking a pace. Few, perhaps none, have gone so far so fast from weakness to strength. Especially the modernization of China’s Navy has been a focal point of debate regarding the evolving security environm......The rise of China in recent decades has taken place on an unprecedented scale and at a breathtaking a pace. Few, perhaps none, have gone so far so fast from weakness to strength. Especially the modernization of China’s Navy has been a focal point of debate regarding the evolving security...... environment in Asia. Deduced from defensive and offensive realism, this paper makes theoretically informed hypotheses and predicts corresponding naval force postures expected in each hypothesis. The hypotheses are then tested on the empirical data to explain China’s strategic behaviour and procurement...

  6. Scientific Ocean Drilling to Assess Submarine Geohazards along European Margins (United States)

    Ask, M. V.; Camerlenghi, A.; Kopf, A.; Morgan, J. K.; Ocean DrillingSeismic Hazard, P. E.


    Submarine geohazards are some of the most devastating natural events in terms of lives lost and economic impact. Earthquakes pose a big threat to society and infrastructure, but the understanding of their episodic generation is incomplete. Tsunamis are known for their potential of striking coastlines world-wide. Other geohazards originating below the sea surface are equally dangerous for undersea structures and the coastal population: submarine landslides and volcanic islands collapse with little warning and devastating consequences. The European scientific community has a strong focus on geohazards along European and nearby continental margins, especially given their high population densities, and long historic and prehistoric record of hazardous events. For example, the Mediterranean is surrounded by very densely-populated coastline and is the World's leading holiday destination, receiving up 30% of global tourism. In addition, its seafloor is criss-crossed by hydrocarbon pipelines and telecommunication cables. However, the governing processes and recurrence intervals of geohazards are still poorly understood. Examples include, but are not limited to, earthquakes and volcanic eruptions along the active tectonic margins of the Mediterranean and Sea of Marmara, landslides on both active and passive margins, and tsunamites and seismites in the sedimentary record that suggest a long history of similar events. The development of geophysical networks, drilling, sampling and long-term monitoring are crucial to the understanding of earthquake, landslide, and tsunami processes, and to mitigate the associated risks in densely populated and industrialized regions such as Europe. Scientific drilling, particularly in the submarine setting, offers a unique tool to obtain drill core samples, borehole measurements and long-term observations. Hence, it is a critical technology to investigate past, present, and possible future influences of hazardous processes in this area. The

  7. Robotic Arm Biobarrier Cable (United States)


    This image, taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander on the 14th Martian day of the mission (June 7, 2008), shows the cable that held the Robotic Arm's biobarrier in place during flight has snapped. The cable's springs retracted to release the biobarrier right after landing. To the lower right of the image a spring is visible. Extending from that spring is a length of cable that snapped during the biobarrier's release. A second spring separated from the cable when it snapped and has been photographed on the ground under the lander near one of the legs. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  8. AC Cable: Yokohama Project (United States)

    Masuda, Takato

    High Temperature Superconducting (HTS) cables can transmit large amounts of electricity in a compact size with minimal losses. Therefore, they are expected to save the construction cost of underground lines in urban areas and decrease transmission losses. Several HTS cables have recently been demonstrated in networks around the world, and full-scale commercialization is expected in the near future. In Japan, the development of compact HTS cables suitable for urban deployment has been underway since the early 1990s. In 2007, a national project was started to verify their operational performance and long-term reliability in the grid. An HTS cable 240 m long was installed at the Asahi substation of the Tokyo Electric Power Company (TEPCO) in Yokohama; then a joint, terminations and cooling system was constructed in 2011. After successful performance tests, the cable was connected to the grid for the first time in Japan, and started to deliver electricity to 70,000 households in October 2012. This trouble-free in-grid service continued for over a year. We can conclude that the HTS cable system performs well and has the stability required for long-term in-grid operations.

  9. Instrumentation Cables Test Plan

    Energy Technology Data Exchange (ETDEWEB)

    Muna, Alice Baca [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); LaFleur, Chris Bensdotter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    A fire at a nuclear power plant (NPP) has the potential to damage structures, systems, and components important to safety, if not promptly detected and suppressed. At Browns Ferry Nuclear Power Plant on March 22, 1975, a fire in the reactor building damaged electrical power and control systems. Damage to instrumentation cables impeded the function of both normal and standby reactor coolant systems, and degraded the operators’ plant monitoring capability. This event resulted in additional NRC involvement with utilities to ensure that NPPs are properly protected from fire as intended by the NRC principle design criteria (i.e., general design criteria 3, Fire Protection). Current guidance and methods for both deterministic and performance based approaches typically make conservative (bounding) assumptions regarding the fire-induced failure modes of instrumentation cables and those failure modes effects on component and system response. Numerous fire testing programs have been conducted in the past to evaluate the failure modes and effects of electrical cables exposed to severe thermal conditions. However, that testing has primarily focused on control circuits with only a limited number of tests performed on instrumentation circuits. In 2001, the Nuclear Energy Institute (NEI) and the Electric Power Research Institute (EPRI) conducted a series of cable fire tests designed to address specific aspects of the cable failure and circuit fault issues of concern1. The NRC was invited to observe and participate in that program. The NRC sponsored Sandia National Laboratories to support this participation, whom among other things, added a 4-20 mA instrumentation circuit and instrumentation cabling to six of the tests. Although limited, one insight drawn from those instrumentation circuits tests was that the failure characteristics appeared to depend on the cable insulation material. The results showed that for thermoset insulated cables, the instrument reading tended to drift

  10. Tsunami Generated by a Two-Phase Submarine Debris Flow (United States)

    Pudasaini, S. P.


    strong and bore-type tsunami waves and run-ups in the coastal lines, and debris slide and deposition at the bottom floor. Strong debris shock waves are generated that travel upstream. Once the debris supply ceases, the shock front is diffused. The model analysis also includes mixing and separation of phases, including inter-phase mass and momentum exchanges and generation and interactions of solid and fluid waves. The state of the solid volume fraction governs the evolution of the fluid extra stress and thus effectively dominates the entire flow dynamics. So, the actual knowledge of the solid volume fraction is essential for the prediction of the turbidity currents, sediment transport and deposition in the subaerial and submarine environments. Applications of this model include (i) the sediment transport on hill slopes, river streams, hydraulic channels (e.g., hydropower dams and plants); lakes, fjords, coastal lines, and aquatic ecology; and (ii) submarine debris impact and the rupture of fiber optic, submarine cables and pipelines in ocean floor, and damage to offshore drilling platforms. The Phase-Froude numbers (the solid and fluid Froude numbers) are introduced that change drastically as the debris mass hits the fluid dam. The Phase-Froude numbers can be subcritical or super-critical, suggesting that the tsunami may be following or preceding the wave generating submarine slide and thus enhancing or reducing the tsunami waves. It is observed that the submarine debris front speed can be faster than the tsunami wave speed. This information can be useful for the early warning strategy in the coastal regions. These findings substantially increase the dynamical understanding of complex multi-phase systems and flows, allowing proper modeling of landslide and debris induced tsunami, the dynamics of turbidity currents and sediment transport, with associated applications in hazard mitigation, geomorphology and sedimentology.

  11. SCICEX: Submarine Arctic Science Program, Version 1 (United States)

    National Aeronautics and Space Administration — The Submarine Arctic Science Program, SCICEX, is a federal interagency collaboration among the operational Navy, research agencies, and the marine research community...

  12. VT Cable Modem Systems 2013 (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable Modem dataset (CABLEMOD2013) includes lines depicting the extent of Vermont's cable modem broadband system as of 6/30/2013. This data...

  13. VT Cable Modem Systems 2007 (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable Modem dataset (CABLEMOD2007) includes lines depicting the extent of Vermont's cable modem broadband system as of 12/31/2007. This...

  14. VT Cable Modem Systems 2005 (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable Modem dataset (CABLEMOD2005) includes lines depicting the extent of Vermont's cable modem broadband system as of 12/31/2005. This...

  15. Economical Aspects of Superconducting Cable (United States)

    Ohya, Masayoshi

    High-temperature superconducting (HTS) cables are expected to resolve technical problems with power grids because they put large-capacity, low-loss power transmission into a compact package. One problem is replacing old 275-kV oil filled (OF) cables with cross-linked polyethylene insulated vinyl sheath cables (XLPE cables). This is difficult because XLPE cable has a lower transmission capacity than OF cable. In addition, the high concentration of public infrastructure underground makes it extremely difficult to build new ones. However, if 66-kV HTS cables can be installed inside existing underground conduits and can achieve a power capacity equivalent to conventional 275-kV cables, construction costs could be significantly reduced. Moreover, if XLPE cables are used for a 1,000 MVA-class transmission line, then three circuits of nine 275-kV single-core cables would be required, which would incur a transmission loss of 90 W/m/cct. Three circuits of three 66-kV Three-in-One HTS cables, however, with an AC loss of 1 W/m/ph@3 kA, heat invasion of 2 W/m, and cooling system efficiency of 0.1, would reduce transmission loss to less than three-fifths that of XLPE cables.

  16. High Temperature Superconducting Underground Cable

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, Roger, A.


    The purpose of this Project was to design, build, install and demonstrate the technical feasibility of an underground high temperature superconducting (HTS) power cable installed between two utility substations. In the first phase two HTS cables, 320 m and 30 m in length, were constructed using 1st generation BSCCO wire. The two 34.5 kV, 800 Arms, 48 MVA sections were connected together using a superconducting joint in an underground vault. In the second phase the 30 m BSCCO cable was replaced by one constructed with 2nd generation YBCO wire. 2nd generation wire is needed for commercialization because of inherent cost and performance benefits. Primary objectives of the Project were to build and operate an HTS cable system which demonstrates significant progress towards commercial progress and addresses real world utility concerns such as installation, maintenance, reliability and compatibility with the existing grid. Four key technical areas addressed were the HTS cable and terminations (where the cable connects to the grid), cryogenic refrigeration system, underground cable-to-cable joint (needed for replacement of cable sections) and cost-effective 2nd generation HTS wire. This was the world’s first installation and operation of an HTS cable underground, between two utility substations as well as the first to demonstrate a cable-to-cable joint, remote monitoring system and 2nd generation HTS.

  17. The Danish Superconducting Cable Project

    DEFF Research Database (Denmark)

    Tønnesen, Ole


    The design and construction of a superconducting cable is described. The cable has a room temperature dielectric design with the cryostat placed inside the electrical insulation.BSCCO 2223 superconducting tapes wound in helix form around a former are used as the cable conductor. Results from...

  18. Static Dissipative Cable Ties, Such as for Radiation Belt Storm Probes (United States)

    Langley, Patrick T. (Inventor); Siddique, Fazle E. (Inventor)


    An article, such as, but not limited to, a cable strap to wrap, support, or secure one or more wires or cables, is formed by cyclically heating and cooling and/or irradiating an article formed of a static dissipative ethylene tetrafluoroethylen (ETFE) resin, to reduce an electrical resistivity and/or to increase a tensile strength of the article.

  19. Impact of Submarine Geohazards on Organic Carbon Burial Offshore Southwestern Taiwan (United States)

    Su, C. C.; Tsai, P. H.; Liu, J. T.; Hsu, S. K.; Chiu, S. D.


    The tectonically active setting and climatic conditions give Taiwan a high exposure to severe natural hazards. After the Pingtung Earthquake and Morakot Typhoon which occurred in 2006 and 2009, the turbidity currents caused a series of submarine cable breaks along the Gaoping and Fangliao Submarine Canyons off SW Taiwan. Large amounts of terrestrial sediments were fast transported bypass the narrow continental shelf and rapidly moved southward through submarine canyons to the deep sea. Two piston cores which were taken from the Tsangyao Ridge and its adjacent area (OR5-1302-2-MT7 and MT6) might shed light on understanding the export of terrestrial organic carbon to the abyss by submarine geo-hazards. The 210Pb profile of MT7 in conjunction with the grain size data indicates the existence of the Pingtung Earthquake and Morakot Typhoon related deposits. The sedimentation rate of these two cores which derived from 210Pb is approximately 0.05 cm/yr. The cores collected from the Gaoping Submarine Canyon, Gaoping Slope and Fangliao Submarine Canyon are used for analyzing TOC, organic C/N and δ13C ratios. The concentrations of total organic carbon are ~0.5%, and C/N rations almost remain between 4 and 8. The high TOC (~1%) and C/N ratio (>10) are observed in the samples with plant debris. The fluctuation of TOC and C/N ratios in near-shore samples is higher than deep sea. In terms of δ13C-values, it progressively decreases with distances from coastal zone to the deep sea. Due to the larger proportions of land-derived organic carbon, the δ13C-values in the surface sediment of upper Gaoping Submarine Canyon, Gaoping Slope, and the turbidite layers at the head of Fangliao Submarine Canyon are lighter. Furthermore, we use the TOC concentrations and δ13C-values to estimate the fractional contributions of terrestrial organic carbon by a simple two component mixing model, and integrate with the 210Pb-derived sediment accumulation rates to evaluate the organic carbon burial

  20. Submarines, spacecraft and exhaled breath. (United States)

    Pleil, Joachim D; Hansel, Armin


    Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another

  1. The Coaxial Cable

    Indian Academy of Sciences (India)

    metal pipe you see direct proof that electromagnetic energy does propagate through a tube. Light is an electromagnetic wave! Then why do cable TV operators put in an inner wire? To find the answer, we need to write down all the relevant equations and solve them. This looks like a problem in calculus, but, as you will see, ...

  2. Exceptional Cable Television. (United States)

    Hunt, Edmund B.; Reid, John E., Jr.


    Ways in which the resources of a university's special education, communication arts, and library services can be combined with those of special education consortiums or parent organizations to provide exceptional children and their parents and teachers with high-quality cable educational television programs that meet their varied needs are…

  3. Near-Real-Time Sismo-acoustic Submarine Station for offshore monitoring (United States)

    D'Anna, Giuseppe; D'Alessandro, Antonino; Fertitta, Gioacchino; Fraticelli, Nicola; Calore, Daniele


    From the early 1980's, Italian seismicity is monitored by the National Seismic Network (NSN). The network has been considerably enhanced by INGV since 2005 by 24-bit digital stations equipped with broad-band sensors. The NSN is nowadays constituted by about 300 on-land seismic station able to detect and locate also small magnitude earthquake in the whole Italian peninsula. However, the lack of offshore seismic stations does not allow the accurate estimation of hypocentral and focal parameters of small magnitude earthquakes occurring in offshore areas. As in the Mediterranean area there is an intense offshore seismic activity, an extension of the seismic monitoring to the sea would be beneficial. There are two types of stations that could be used to extend the network towards the sea: the first type is connected to the coast though a cable, the second type is isolated (or stand alone) and works autonomously. Both solutions have serious limitations: the first one, for several technical and economic problems, linked to the indispensable transmission/alimentation cable, cannot be installed far from the coast; the second one, allows access to the recorded data, only after they are recovered from the seabed. It is clear that these technical solutions are not suitable for the real time monitoring of the offshore seismicity or for the realization of a tsunami warning system. For this reason, in early 2010, the OBSLab of Gibilmanna begins the design of a submarine station able to overcome the limitations of the two systems above. The station isbuilt under the project EMSO-MedIT. The two stations built have already been tested in dock and ready for installation. One of this station will be installed, in few time, in the southern Tyrrhenian Sea, near the epicentre of the Palermo 2002 main shock. The sea bottom station will be equipped with 2 very broadband 3C seismometers, a broad band hydrophone, a differential and an absolute pressure gauge. The station includes a submarine

  4. Submarine landslides: advances and challenges (United States)

    Locat, Jacques; Lee, Homa J.


    Due to the recent development of well-integrated surveying techniques of the sea floor, significant improvements were achieved in mapping and describing the morphology and architecture of submarine mass movements. Except for the occurrence of turbidity currents, the aquatic environment (marine and fresh water) experiences the same type of mass failure as that found on land. Submarine mass movements, however, can have run-out distances in excess of 100 km, so their impact on any offshore activity needs to be integrated over a wide area. This great mobility of submarinemass movements is still not very well understood, particularly for cases like the far-reaching debris flows mapped on the Mississippi Fan and the large submarine rock avalanches found around many volcanic islands. A major challenge ahead is the integration of mass movement mechanics in an appropriate evaluation of the hazard so that proper risk assessment methodologies can be developed and implemented for various human activities offshore, including the development of natural resources and the establishment of reliable communication corridors. Key words : submarine slides, hazards, risk assessment, morphology, mobility, tsunami. Le dveloppement rcent de techniques de levs hydrograhiques pour les fonds marins nous a permis d'atteindre une qualit ingale dans la cartographie et la description des glissements sous marins. l'exception des courants de turbidit, on retrouve dans le domaine aquatique les mmes types de mouvements de terrain que sur terre. Par contre, les glissements sous-marins peuvent atteindre des distances excdant 100 km de telle sorte que leur impact sur les activits offshore doit tre pris en compte sur degrandes tendues. La grande mobilit des glissements sous-marins n'est pas encore bien comprise, comme pour le cas des coules dedbris cartographies sur le cne du Mississippi ainsi que pour les grandes avalanches rocheuses sous-marines retrouves au pourtour des les volcaniques. Un dfi majeur

  5. Development of inspection robots for bridge cables. (United States)

    Yun, Hae-Bum; Kim, Se-Hoon; Wu, Liuliu; Lee, Jong-Jae


    This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

  6. Development of Inspection Robots for Bridge Cables

    Directory of Open Access Journals (Sweden)

    Hae-Bum Yun


    Full Text Available This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

  7. Method to improve superconductor cable (United States)

    Borden, A.R.


    A method is disclosed of making a stranded superconductor cable having improved flexing and bending characteristics. In such method, a plurality of superconductor strands are helically wound around a cylindrical portion of a mandrel which tapers along a transitional portion to a flat end portion. The helically wound strands form a multistrand hollow cable which is partially flattened by pressure rollers as the cable travels along the transitional portion. The partially flattened cable is impacted with repeated hammer blows as the hollow cable travels along the flat end portion. The hammer blows flatten both the internal and the external surfaces of the strands. The cable is fully flattened and compacted by two sets of pressure rollers which engage the flat sides and the edges of the cable after it has traveled away from the flat end portion of the mandrel. The flattened internal surfaces slide easily over one another when the cable is flexed or bent so that there is very little possibility that the cable will be damaged by the necessary flexing and bending required to wind the cable into magnet coils.

  8. Similarities between rivers and submarine channels (United States)

    Balcerak, Ernie


    Scientists have long known that the width and depth of rivers follows a power law relationship with discharge. They have also noticed that submarine channels appear to be similar to terrestrial rivers, but there have not been many systematic comparisons of the relationships between submarine channel morphology and discharge. Konsoer et al. compared the width, depth, and slope of 177 submarine channels to those of 231 river cross sections. They found that submarine channels are up to an order of magnitude wider and deeper than the largest terrestrial rivers, but they exhibit a similar power law relationship between width and depth. For submarine channels that were similar in size to rivers, the authors found that submarine channels tend to be 1 to 2 orders of magnitude steeper than rivers. The authors also inferred values for sediment concentration in the turbidity currents in the channels and combined this with estimated mean flow velocities to look for a relationship between discharge and morphology in the channels. They found that like rivers, the width and depth of the submarine channels follow a power law scaling with discharge. (Journal of Geophysical Research-Earth Surface, doi:10.1029/2012JF002422, 2013)

  9. Cable networks, services, and management

    CERN Document Server


    Cable Networks, Services, and Management is the first book to cover cable networks, services, and their management, in-depth, for network operators, engineers, researchers, and students. Thirteen experts in various fields have contributed their knowledge of network architectures and services, Operations, Administration, Maintenance, Provisioning, Troubleshooting (OAMPT) for residential and business services, cloud, Software Defined Networks (SDN), as well as virtualization concepts and their applications as part of the future directions of cable networks. The book begins by introducing architecture and services for Data Over Cable Service Interface Specification (DOCSIS) 3.0/ 3.1, Converged Cable Access Platform (CCAP), Content Distribution Networks (CDN, IP TV, and Packet Cable and Wi-Fi for Residential Services. Topics that are discussed in proceeding chapters include: operational systems and management architectures, service orders, provisioning, fault manageme t, performance management, billing systems a...

  10. Non-Intrusive Cable Tester (United States)

    Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)


    A cable tester is described for low frequency testing of a cable for faults. The tester allows for testing a cable beyond a point where a signal conditioner is installed, minimizing the number of connections which have to be disconnected. A magnetic pickup coil is described for detecting a test signal injected into the cable. A narrow bandpass filter is described for increasing detection of the test signal. The bandpass filter reduces noise so that a high gain amplifier provided for detecting a test signal is not completely saturate by noise. To further increase the accuracy of the cable tester, processing gain is achieved by comparing the signal from the amplifier with at least one reference signal emulating the low frequency input signal injected into the cable. Different processing techniques are described evaluating a detected signal.

  11. Dynamic testing of cable structures

    Directory of Open Access Journals (Sweden)

    Caetano Elsa


    Full Text Available The paper discusses the role of dynamic testing in the study of cable structures. In this context, the identification of cable force based on vibration measurements is discussed. Vibration and damping assessment are then introduced as the focus of dynamic monitoring systems, and particular aspects of the structural behaviour under environmental loads are analysed. Diverse application results are presented to support the discussion centred on cable-stayed bridges, roof structures, a guyed mast and a transmission line.

  12. Electromagnetic transients in power cables

    CERN Document Server

    da Silva, Filipe Faria


    From the more basic concepts to the most advanced ones where long and laborious simulation models are required, Electromagnetic Transients in Power Cables provides a thorough insight into the study of electromagnetic transients and underground power cables. Explanations and demonstrations of different electromagnetic transient phenomena are provided, from simple lumped-parameter circuits to complex cable-based high voltage networks, as well as instructions on how to model the cables.Supported throughout by illustrations, circuit diagrams and simulation results, each chapter contains exercises,

  13. Calciclastic submarine fans: An integrated overview (United States)

    Payros, Aitor; Pujalte, Victoriano


    Calciclastic submarine fans are rare in the stratigraphic record and no bona fide present-day analogue has been described to date. Possibly because of that, and although calciclastic submarine fans have long intrigued deep-water carbonate sedimentologists, they have largely been overlooked by the academic and industrial communities. To fill this gap we have compiled and critically reviewed the existing sedimentological literature on calciclastic submarine fans, thus offering an updated view of this type of carbonate slope sedimentary system. Calciclastic submarine fans range in length from just a few to more than 100 km. Three different types can be distinguished: (1) Coarse-grained, small-sized (depression associated with tectonic structures, an inherited topography, or large-scale mass failures.

  14. Aspects of Propeller Developements for a Submarine

    DEFF Research Database (Denmark)

    Andersen, Poul; kappel, Jens Julius; Spangenberg, Eugen


    Design and development of propellers for submarines are in some ways different from propellers for surface vessels. The most important demand is low acoustic signature that has priority over propeller efficiency, and the submarine propeller must be optimized with respect to acoustics rather than...... efficiency. Moreover the operating conditions of a submarine propeller are quite different. These aspects are discussed as well as the weighing of the various propeller parameters against the design objectives. The noise generated by the propeller can be characterized as thrust noise due to the inhomogeneous...... wake field of the submarine, trailing-edge noise and noise caused by turbulence in the inflow. The items discussed are demonstrated in a case study where a propeller of the Kappel type was developed. Three stages of the development are presented, including a design of an 8-bladed propeller where...

  15. Russia's Submarine Force: Determinants and Prospects

    National Research Council Canada - National Science Library

    Tully, John


    ... the determinants of these events, The Russian Federation inherited a huge submarine fleet from the Soviet Union, Due to the changing conditions in the world and in Russia, its future status is in doubt...

  16. Submarine Pipeline Locations - USACE IENC (United States)

    Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

  17. Submarine Pipeline Lines - USACE IENC (United States)

    Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

  18. SSN 774 Virginia Class Submarine (SSN 774) (United States)


    Report: The VIRGINIA Class Submarine Program continues to deliver submarines within cost, ahead of schedule , with improved quality and with...baseline schedule threshold set ten years earlier, in 1994. June 20, 2006: USS TEXAS, which was essentially the second lead ship of the class , is the first...factored for the VIRGINIA Class based on weight. Public and private shipyard data was used, as well as the maintenance schedule provided in the CARD, Rev E

  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 1: Cables for rated voltages of 1 kV (Um = 1,2 kV) and 3 kV (Um = 3,6 kV)

    CERN Document Server

    International Electrotechnical Commission. Geneva


    Specifies the construction, dimensions and test requirements of power cables with extruded solid insulation for rated voltages of 1 kV (Um = 1,2 kV) and 3 kV (Um = 3,6 kV) for fixed installations such as distribution networks or industrial installations. This standard includes cables which exhibit properties of reduced flame spread, low levels of smoke emission and halogen-free gas emission when exposed to fire. Cables for special installation and service conditions are not included, for example cables for overhead networks, the mining industry, nuclear power plants (in and around the containment area), submarine use or shipboard application. The main changes with respect to the first edition relate to insulation and oversheath thickness requirements, and inclusion of constructions and requirements for halogen free cables with reduced flame propagation and low levels of smoke emission.

  20. Submarine landslides: processes, triggers and hazard prediction. (United States)

    Masson, D G; Harbitz, C B; Wynn, R B; Pedersen, G; Løvholt, F


    Huge landslides, mobilizing hundreds to thousands of km(3) of sediment and rock are ubiquitous in submarine settings ranging from the steepest volcanic island slopes to the gentlest muddy slopes of submarine deltas. Here, we summarize current knowledge of such landslides and the problems of assessing their hazard potential. The major hazards related to submarine landslides include destruction of seabed infrastructure, collapse of coastal areas into the sea and landslide-generated tsunamis. Most submarine slopes are inherently stable. Elevated pore pressures (leading to decreased frictional resistance to sliding) and specific weak layers within stratified sequences appear to be the key factors influencing landslide occurrence. Elevated pore pressures can result from normal depositional processes or from transient processes such as earthquake shaking; historical evidence suggests that the majority of large submarine landslides are triggered by earthquakes. Because of their tsunamigenic potential, ocean-island flank collapses and rockslides in fjords have been identified as the most dangerous of all landslide related hazards. Published models of ocean-island landslides mainly examine 'worst-case scenarios' that have a low probability of occurrence. Areas prone to submarine landsliding are relatively easy to identify, but we are still some way from being able to forecast individual events with precision. Monitoring of critical areas where landslides might be imminent and modelling landslide consequences so that appropriate mitigation strategies can be developed would appear to be areas where advances on current practice are possible.

  1. Motility of electric cable bacteria

    DEFF Research Database (Denmark)

    Bjerg, Jesper Tataru; Damgaard, Lars Riis; Holm, Simon Agner


    Cable bacteria are filamentous bacteria that electrically couple sulfide oxidation and oxygen reduction at centimeter distances, and observations in sediment environments have suggested that they are motile. By time-lapse microscopy, we found that cable bacteria used gliding motility on surfaces...

  2. Cable Bacteria in Freshwater Sediments

    DEFF Research Database (Denmark)

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus


    In marine sediments cathodic oxygen reduction at the sediment surface can be coupled to anodic sulfide oxidation in deeper anoxic layers through electrical currents mediated by filamentous, multicellular bacteria of the Desulfobulbaceae family, the so-called cable bacteria. Until now, cable...... bacteria have only been reported from marine environments. In this study, we demonstrate that cable bacteria also occur in freshwater sediments. In a first step, homogenized sediment collected from the freshwater stream Giber Å, Denmark, was incubated in the laboratory. After 2 weeks, pH signatures...... marine cable bacteria, with the genus Desulfobulbus as the closest cultured lineage. The results of the present study indicate that electric currents mediated by cable bacteria could be important for the biogeochemistry in many more environments than anticipated thus far and suggest a common evolutionary...

  3. Length of a Hanging Cable

    Directory of Open Access Journals (Sweden)

    Eric Costello


    Full Text Available The shape of a cable hanging under its own weight and uniform horizontal tension between two power poles is a catenary. The catenary is a curve which has an equation defined by a hyperbolic cosine function and a scaling factor. The scaling factor for power cables hanging under their own weight is equal to the horizontal tension on the cable divided by the weight of the cable. Both of these values are unknown for this problem. Newton's method was used to approximate the scaling factor and the arc length function to determine the length of the cable. A script was written using the Python programming language in order to quickly perform several iterations of Newton's method to get a good approximation for the scaling factor.

  4. The Dragonian Subsurface Abyss and Submarine Force’s Ability to Counter the Rising Threat (United States)


    36Desmond Ball , Trends in Military Acquisitions in the Asia-Pacific Region : Implications for Security and Prospects for Constraints and Controls...accessed January 24, 2013). 53IHS Jane’s, "Enter the Dragon : Inside China’s New Model Navy," Jane’s Navy International, April 20, 2011. https...99s-overhyped-submarine-threat/ (accessed November 7, 2011). Ball , Desmond. Trends in Military Acquisitions in the Asia-Pacific Region : Implications

  5. Study of Transient Heat Transport Mechanisms in Superfluid Helium Cooled Rutherford-Cables

    CERN Document Server


    The Large Hadron Collider leverages superconducting magnets to focus the particle beam or keep it in its circular track. These superconducting magnets are composed of NbTi-cables with a special insulation that allows superfluid helium to enter and cool the superconducting cable. Loss mechanisms, e.g. continuous random loss of particles escaping the collimation system heating up the magnets. Hence, a local temperature increase can occur and lead to a quench of the magnets when the superconductor warms up above the critical temperature. A detailed knowledge about the temperature increases in the superconducting cable (Rutherford type) ensures a secure operation of the LHC. A sample of the Rutherford cable has been instrumented with temperature sensors. Experiments with this sample have been performed within this study to investigate the cooling performance of the helium in the cable due to heat deposition. The experiment uses a superconducting coil, placed in a cryostat, to couple with the magnetic field loss m...

  6. 10BASE5 Ethernet Cable & Vampire Tap

    CERN Multimedia


    10BASE5 Thick Ethernet Cable, 10Mbit/sec. In the 1980s and early 1990's, Ethernet became more popular and provided a much faster data transmission rate. This cable is one of the first ethernet cables from 1983, a thick, bulky affair. Computers were attached via "Vampire Taps" which were connectors screwed straight through the shielding of the cable.

  7. 14 CFR 27.1365 - Electric cables. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Electric cables. 27.1365 Section 27.1365... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Electrical Systems and Equipment § 27.1365 Electric cables. (a) Each electric connecting cable must be of adequate capacity. (b) Each cable that would overheat...

  8. Thermal analysis of underground power cable system (United States)

    Rerak, Monika; Ocłoń, Paweł


    The paper presents the application of Finite Element Method in thermal analysis of underground power cable system. The computations were performed for power cables buried in-line in the ground at a depth of 2 meters. The developed mathematical model allows determining the two-dimensional temperature distribution in the soil, thermal backfill and power cables. The simulations studied the effect of soil and cable backfill thermal conductivity on the maximum temperature of the cable conductor. Also, the effect of cable diameter on the temperature of cable core was studied. Numerical analyses were performed based on a program written in MATLAB.

  9. Secure passive RFID tag with seal (United States)

    Nekoogar, Faranak; Reynolds, Matthew; Lefton, Scott; Dowla, Farid; Twogood, Richard


    A secure passive RFID tag system comprises at least one base station and at least one passive RFID tag. The tag includes a fiber optic cable with the cable ends sealed within the tag and the middle portion forming an external loop. The loop may be secured to at least portions of an object. The tag transmits and receives an optical signal through the fiber optic cable, and the cable is configured to be damaged or broken in response to removal or tampering attempts, wherein the optical signal is significantly altered if the cable is damaged or broken. The tag transmits the optical signal in response to receiving a radio signal from the base station and compares the transmitted optical signal to the received optical signal. If the transmitted optical signal and the received optical signal are identical, the tag transmits an affirmative radio signal to the base station.

  10. Air flow around suspended cables (United States)

    Gołębiowska, Irena; Dutkiewicz, Maciej

    The impact of wind on construction structures is essential issue in design and operation. In particular, the wind can cause the dengerous vibrations of slender structures with low rigidity, eg. vibrations of cables of suspension and cable-stayed bridges or high voltage transmision lines, thus understanding of wind flow around such constructions is significant. In the paper the results of the analysis of wind flow around the cables for different Reynolds number is presented. The analysed flow meets the Navier-Stokes and continuity equations. The circle and elipse section of the cable is analysed. The discusion of vorticity, drag and lift coefficients and cases due to different angle of wind flow action is presented. The boundary layer and its infuence on total flow is analysed.

  11. Air flow around suspended cables

    Directory of Open Access Journals (Sweden)

    Gołębiowska Irena


    Full Text Available The impact of wind on construction structures is essential issue in design and operation. In particular, the wind can cause the dengerous vibrations of slender structures with low rigidity, eg. vibrations of cables of suspension and cable-stayed bridges or high voltage transmision lines, thus understanding of wind flow around such constructions is significant. In the paper the results of the analysis of wind flow around the cables for different Reynolds number is presented. The analysed flow meets the Navier-Stokes and continuity equations. The circle and elipse section of the cable is analysed. The discusion of vorticity, drag and lift coefficients and cases due to different angle of wind flow action is presented. The boundary layer and its infuence on total flow is analysed.

  12. Motility of electric cable bacteria

    DEFF Research Database (Denmark)

    Bjerg, Jesper Tataru; Damgaard, Lars Riis; Holm, Simon Agner


    Cable bacteria are filamentous bacteria that electrically couple sulfide oxidation and oxygen reduction at centimeter distances, and observations in sediment environments have suggested that they are motile. By time-lapse microscopy, we found that cable bacteria used gliding motility on surfaces...... with a highly variable speed of 0.50.3 ms1 (meanstandard deviation) and time between reversals of 155108 s. They frequently moved forward in loops, and formation of twisted loops revealed helical rotation of the filaments. Cable bacteria responded to chemical gradients in their environment, and around the oxic......-anoxic interface, they curled and piled up, with straight parts connecting back to the source of sulfide. Thus, it appears that motility serves the cable bacteria in establishing and keeping optimal connections between their distant electron donor and acceptors in a dynamic sediment environment....

  13. Cable SGEMP Code Validation Study

    Energy Technology Data Exchange (ETDEWEB)

    Ballard, William Parker [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Center for CA Weapons Systems Engineering


    This report compared data taken on the Modular Bremsstrahlung Simulator using copper jacketed (cujac) cables with calculations using the RHSD-RA Cable SGEMP analysis tool. The tool relies on CEPXS/ONBFP to perform radiation transport in a series of 1D slices through the cable, and then uses a Green function technique to evaluate the expected current drive on the center conductor. The data were obtained in 2003 as part of a Cabana verification and validation experiment using 1-D geometries, but were not evaluated until now. The agreement between data and model is not adequate unless gaps between the dielectric and outer conductor (ground) are assumed, and these gaps are large compared with what is believed to be in the actual cable.

  14. Geomorphic process fingerprints in submarine canyons (United States)

    Brothers, Daniel S.; ten Brink, Uri S.; Andrews, Brian D.; Chaytor, Jason D.; Twichell, David C.


    Submarine canyons are common features of continental margins worldwide. They are conduits that funnel vast quantities of sediment from the continents to the deep sea. Though it is known that submarine canyons form primarily from erosion induced by submarine sediment flows, we currently lack quantitative, empirically based expressions that describe the morphology of submarine canyon networks. Multibeam bathymetry data along the entire passive US Atlantic margin (USAM) and along the active central California margin near Monterey Bay provide an opportunity to examine the fine-scale morphology of 171 slope-sourced canyons. Log–log regression analyses of canyon thalweg gradient (S) versus up-canyon catchment area (A) are used to examine linkages between morphological domains and the generation and evolution of submarine sediment flows. For example, canyon reaches of the upper continental slope are characterized by steep, linear and/or convex longitudinal profiles, whereas reaches farther down canyon have distinctly concave longitudinal profiles. The transition between these geomorphic domains is inferred to represent the downslope transformation of debris flows into erosive, canyon-flushing turbidity flows. Over geologic timescales this process appears to leave behind a predictable geomorphic fingerprint that is dependent on the catchment area of the canyon head. Catchment area, in turn, may be a proxy for the volume of sediment released during geomorphically significant failures along the upper continental slope. Focused studies of slope-sourced submarine canyons may provide new insights into the relationships between fine-scale canyon morphology and down-canyon changes in sediment flow dynamics.

  15. Static and Dynamic Characteristics of a Long-Span Cable-Stayed Bridge with CFRP Cables

    Directory of Open Access Journals (Sweden)

    Xu Xie


    Full Text Available In this study, the scope of CFRP cables in cable-stayed bridges is studied by establishing a numerical model of a 1400-m span of the same. The mechanical properties and characteristics of CFRP stay cables and of a cable-stayed bridge with CFRP cables are here subjected to comprehensive analysis. The anomalies in the damping properties of free vibration, nonlinear parametric vibration and wind fluctuating vibration between steel cables and CFRP cables are determined. The structural stiffness, wind resistance and traffic vibration of the cable-stayed bridge with CFRP cables are also analyzed. It was found that the static performances of a cable-stayed bridge with CFRP cables and steel cables are basically the same. The natural frequencies of CFRP cables do not coincide with the major natural frequencies of the cable-stayed bridge, so the likelihood of CFRP cable-bridge coupling vibration is minuscule. For CFRP cables, the response amplitudes of both parametric vibration and wind fluctuating vibration are smaller than those of steel cables. It can be concluded from the research that the use of CFRP cables does not change the dynamic characteristics of the vehicle-bridge coupling vibration. Therefore, they can be used in long-span cable-stayed bridges with an excellent mechanical performance.

  16. An overview of the ITER cabling network and cable database management

    Energy Technology Data Exchange (ETDEWEB)

    Sonara, Jashwant, E-mail: [ITER Organization, Route de Vinon sur Verdon, CS 90 046-13067, Saint Paul Lez Durance (France); Beltran, David; Pintea, Bogdan; Hourtoule, Joel; Benfatto, Ivone [ITER Organization, Route de Vinon sur Verdon, CS 90 046-13067, Saint Paul Lez Durance (France); Kim, Sung Hoon; Lee, Kun Ho; Jung, Sun Kyung; Lee, Cheoung-Joon [KEPCO E& C, Yonggudaero, Giheung-gu, Yongin-si, Gyeonggi-do, 446-713 (Korea, Republic of)


    Highlights: • More than 80,000 cables have been registered into ITER centralized cable database. • This cabling represents 28 ITER plant systems and 21,000 equipments including 61,000 non-safety cables and 7300 safety cables. • Development of unique cable engineering management system for diversified cabling requirement. • Use of 2D and 3D softwares and integration of both softwares into bespoke software which can handle 2D and 3D features of the tray network. - Abstract: ITER is a nuclear fusion facility, where many systems with varying functional and physical characteristics coexist. This makes the cabling requirements diverse too. The design of the ITER demands extensive integration of many systems interfaces. This process starts by collating cable requirement data to form a giant cable database with scope for approximately 120,000 cables in total. Ultimately the cabling installation will be approximately twice the size of one required for a 3rd generation nuclear fission power plant, with cables spanning more than 12,000 km to be installed within approximately 200 km of cable trays. Considering the differing cabling requirements, the raceway network and cables shall be routed in a prescribed manner to comply with French Nuclear Safety standards. This paper describes an overview of the ITER cabling network, the cable engineering design workflow, development and management of the cable database and integration between the software tools.


    Directory of Open Access Journals (Sweden)

    G.V. Bezprozvannych


    Full Text Available Observation of contact electrification of power cable samples is made. It is revealed that the contact potential difference and the capacity formed under separation of free charges on the surfaces of the contacting materials depend on cable design, applied materials, and inspection schemes. Time series of capacity drift and dielectric loss tangent caused by instability of triboelectric charging of the contacting surfaces are presented.

  18. Cable Driven Devices for Telemanipulation


    Ferraresi, Carlo; Pescarmona, Francesco


    Cable driven robotic devices present peculiar aspects, requiring the solution of very specific problems. As regards the determination of the main operational characteristics, like the workspace, it is necessary to consider that such devices are often parallel and redundant structures. Moreover, cables can only exert traction forces. As a consequence, the development of such structures requires coping with two main aspects: (a) the solution of forward kinematics and inverse statics, necessary ...


    Directory of Open Access Journals (Sweden)

    Yogi Noviadi


    Full Text Available The coastal and offshore areas around the Sunda Strait will be developed to be a submarine cable corridor connecting between Java and Sumatra Islands. There are some requirements that should be considered before laying the underwater cables. One of these considerations is to understand the seafloor morphology of the Sunda Strait. The study was conducted based on six of track lines with 1 km line spacing and 4 Cross lines. The water depth obtained then was corrected to the depth of water from the Lowest Water Level (LWL. The seabed condition in the near shore area of Sumatra side is very flat and is influenced by 2 km offshore tide activity. The coast line is characterized by mangrove and fine fraction of sediments (mud and clay. At the Java side, the coastal morphology is characterized by the very steep slope and most of the area is occupied by the industrial activities.

  20. Identifiable piezoelectric security system design (United States)

    Li, Zhenyu; Zhang, Xiaoming


    Directing at the disadvantages of low environmental suitability, inferior anti-interference ability and being easy to be found and destroyed in existing security product, a kind of identifiable piezoelectric security system based on piezoelectric cable is designed. The present system gathers vibration signals of different moving bodies, such as human, vehicles, animals and so on, with piezoelectric cable buried under -ground and distinguishes the different moving bodies through recognition algorithm and thus giving an alarm. As is shown in experiments, the present system has the features of good concealment and high accuracy in distinguishing moving bodies.

  1. German Submarine Offensives and South African Countermeasures

    African Journals Online (AJOL)


    'Good Hunting': German Submarine Offensives and South African. Countermeasures off the South African Coast during the Second World. War, 1942-1945. Evert Kleynhans. •. Abstract .... wolf packs south, Dönitz had hoped to cause a diversionary effect whereby the Allies would be forced to split their defensive forces ...

  2. Monitoring of the nuclear submarine Komsomolets

    Energy Technology Data Exchange (ETDEWEB)

    Heldal, Hilde E.; Flo, Janita K.; Liebig, Penny L. [Institute of Marine Research, P. O. Box 1870 Nordnes, N-5817 Bergen (Norway); Gaefvert, Torbjoern; Rudjord, Anne Liv [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Oesteraas (Norway); Gwynn, Justin P. [Norwegian Radiation Protection Authority, The Fram Centre, N-9296 Tromsoe (Norway)


    The Soviet nuclear submarine Komsomolets sank on the 7 April 1989, 180 km southwest of Bear Island in the Norwegian Sea to a depth of about 1655 m. The submarine contains one nuclear reactor containing long-lived radionuclides such as cesium-137 ({sup 137}Cs) along with other fission and activation products, in addition to 2 mixed uranium/plutonium nuclear warheads containing weapons grade plutonium. Although several model studies have shown that a radioactive leakage from Komsomolets will have insignificant impact on fish and other marine organisms, there are still public concerns about the condition of the submarine and the potential for radioactive leakage. In order to document the contamination levels and to meet public concerns, monitoring of radioactive contamination in the area adjacent to the submarine has been ongoing since 1993. Samples of bottom seawater and sediments have been collected annually by the Institute of Marine Research (IMR) and have been analysed for {sup 137}Cs and plutonium-239,240 ({sup 239,240}Pu). So far, activity concentrations in the samples have been comparable to levels found in other samples from the Norwegian and Barents Seas. During sampling from R/V 'G. O. Sars' in April 2013, an area of about 1 km{sup 2} of the seabed around Komsomolets was mapped to precisely locate the submarine using a Kongsberg EM302 multibeam echo sounder, a Simrad EK60 single beam echo sounder and an Olex 3D bottom-mapping system. For sediment sampling, a Simrad MST342 mini-transponder was attached to a Smoegen box corer to allow for precise positioning of the corer. With the aid of the Kongsberg HiPAP (High Precision Acoustic Positioning) system, 4 box cores were collected around the submarine at a distance of 10 to 20 m. In addition, one box core was collected from a reference station about 100 m upstream of the submarine. Surface sediments and sediment cores were collected from the box cores taken at each sampling location. Sediment cores

  3. Chemical environments of submarine hydrothermal systems (United States)

    Shock, Everett L.


    Perhaps because black-smoker chimneys make tremendous subjects for magazine covers, the proposal that submarine hydrothermal systems were involved in the origin of life has caused many investigators to focus on the eye-catching hydrothermal vents. In much the same way that tourists rush to watch the spectacular eruptions of Old Faithful geyser with little regard for the hydrology of the Yellowstone basin, attention is focused on the spectacular, high-temperature hydrothermal vents to the near exclusion of the enormous underlying hydrothermal systems. Nevertheless, the magnitude and complexity of geologic structures, heat flow, and hydrologic parameters which characterize the geyser basins at Yellowstone also characterize submarine hydrothermal systems. However, in the submarine systems the scale can be considerably more vast. Like Old Faithful, submarine hydrothermal vents have a spectacular quality, but they are only one fascinating aspect of enormous geologic systems operating at seafloor spreading centers throughout all of the ocean basins. A critical study of the possible role of hydrothermal processes in the origin of life should include the full spectrum of probable environments. The goals of this chapter are to synthesize diverse information about the inorganic geochemistry of submarine hydrothermal systems, assemble a description of the fundamental physical and chemical attributes of these systems, and consider the implications of high-temperature, fluid-driven processes for organic synthesis. Information about submarine hydrothermal systems comes from many directions. Measurements made directly on venting fluids provide useful, but remarkably limited, clues about processes operating at depth. The oceanic crust has been drilled to approximately 2.0 km depth providing many other pieces of information, but drilling technology has not allowed the bore holes and core samples to reach the maximum depths to which aqueous fluids circulate in oceanic crust. Such

  4. Phase 1 Final Report: Titan Submarine (United States)

    Oleson, Steven R.; Lorenz, Ralph D.; Paul, Michael V.


    The conceptual design of a submarine for Saturn's moon Titan was a funded NASA Innovative Advanced Concepts (NIAC) Phase 1 for 2014. The proposal stated the desire to investigate what science a submarine for Titan's liquid hydrocarbon seas might accomplish and what that submarine might look like. Focusing on a flagship class science system (100 kg), it was found that a submersible platform can accomplish extensive science both above and below the surface of the Kraken Mare. Submerged science includes mapping using side-looking sonar, imaging and spectroscopy of the lake, as well as sampling of the lake's bottom and shallow shoreline. While surfaced, the submarine will not only sense weather conditions (including the interaction between the liquid and atmosphere) but also image the shoreline, as much as 2 km inland. This imaging requirement pushed the landing date to Titan's next summer period (2047) to allow for lighted conditions, as well as direct-to-Earth communication, avoiding the need for a separate relay orbiter spacecraft. Submerged and surfaced investigation are key to understanding both the hydrological cycle of Titan as well as gather hints to how life may have begun on Earth using liquid, sediment, and chemical interactions. An estimated 25 Mb of data per day would be generated by the various science packages. Most of the science packages (electronics at least) can be safely kept inside the submarine pressure vessel and warmed by the isotope power system.The baseline 90-day mission would be to sail submerged and surfaced around and through Kraken Mare investigating the shoreline and inlets to evaluate the sedimentary interaction both on the surface and then below. Depths of Kraken have yet to be sensed (Ligeia to the north is thought to be 200 m (656 ft) deep), but a maximum depth of 1,000 m (3,281 ft) for Kraken Mare was assumed for the design). The sub would spend 20 d at the interface between Kraken Mare and Ligeia Mare for clues to the drainage of

  5. Optical Measurement of Cable and String Vibration

    Directory of Open Access Journals (Sweden)

    Y. Achkire


    Full Text Available This paper describes a non contacting measurement technique for the transverse vibration of small cables and strings using an analog position sensing detector. On the one hand, the sensor is used to monitor the cable vibrations of a small scale mock-up of a cable structure in order to validate the nonlinear cable dynamics model. On the other hand, the optical sensor is used to evaluate the performance of an active tendon control algorithm with guaranteed stability properties. It is demonstrated experimentally, that a force feedback control law based on a collocated force sensor measuring the tension in the cable is feasible and provides active damping in the cable.

  6. Miocene Current-Modified Submarine Fans (United States)

    Arce Perez, L. E.; Snedden, J.; Fisher, W. L.


    In the southwestern Gulf of Mexico, new and newly reprocessed seismic data has revealed a series of large bedforms, with set thicknesses of 130 to 250 meters. These exhibit hummocky, oblique and shingled to parallel seismic clinoform reflections. This seismic package has a paleowater depth of 450 meters. Those shingled seismic reflections in offshore east Mexico are interpreted as contourite drift deposits. These Miocene-age contourites may be related to strong ocean bottom currents that modified submarine fans and transported sediment to the north. Those contourites were identified on older seismic data, but are better imaged and interpreted on this new data. Plans are to map out and investigate the origin and extent of fans and contourites that extends over a large area of the Gulf of Mexico. In the Early Miocene several submarine fans systems were formed by the sediment input related to orogenic activity in Mexico. Submarine fan development persisted into the Middle Miocene due to continued uplift and erosion of the Mexican landmass. Initial, contourites are small and close proximity to the deep-water fan. In the Late Miocene time, contourite drift field reached its maximum extent in the Mexican deepwater area, anchored on its southern end by a submarine mound. This mounded submarine fan is located in the offshore northeast Veracruz and can be linked to increased uplift and erosion of the Trans-Mexican volcanic belt. In the Miocene-Pliocene, the large contourite drift begins to diminish in size and scale and is moribund by the Pliocene, with establishment of oceanic circulation similar to the present day. This research is important to understand more about the Gulf of Mexico and also for the Miocene timeframe that is a key phase in the earth's history. The role of the change in bottom water flow during progressive closure of the equatorial seaway separating North and South America will also be investigated.

  7. Static and Dynamic Mechanical Properties of Long-Span Cable-Stayed Bridges Using CFRP Cables

    Directory of Open Access Journals (Sweden)

    Mei Kuihua


    Full Text Available The elastic modulus and deadweight of carbon fiber-reinforced polymer (CFRP cables are different from those of steel cables. Thus, the static and dynamic behaviors of cable-stayed bridges using CFRP cables are different from those of cable-stayed bridges using steel cables. The static and dynamic performances of the two kinds of bridges with a span of 1000 m were studied using the numerical method. The effects of geometric nonlinear factors on static performance of the two kinds of cable-stayed bridges were analyzed. The live load effects and temperature effects of the two cable-stayed bridges were also analyzed. The influences of design parameters, including different structural systems, the numbers of auxiliary piers, and the space arrangement types of cable, on the dynamic performance of the cable-stayed bridge using CFRP cables were also studied. Results demonstrate that sag effect of the CFRP cable is much smaller than that of steel cable. The temperature effects of CFRP cable-stayed bridge are less than those of steel cable-stayed bridge. The vertical bending natural vibration frequency of the CFRP cable-stayed bridge is generally lower than that of steel cable-stayed bridge, whereas the torsional natural vibration frequency of the former is higher than that of the latter.

  8. 76 FR 78159 - Safety Zone; Submarine Cable Installation Project; Chicago River South Branch, Chicago, IL (United States)


    ... W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through... Bridge between Mile Marker 325.1 and Mile Marker 325.5 of the Chicago River South Branch in Chicago... vessels intending to transit or anchor in the vicinity of the Madison Street Bridge between Mile Marker...

  9. Long-term flow monitoring of submarine gas emanations (United States)

    Spickenbom, K.; Faber, E.; Poggenburg, J.; Seeger, C.


    consists of gas collector, sensor head and pressure housing for electronics and power supply. The collector is a plastic funnel, enclosed in a stainless-steel frame to add weight and stability. The whole unit is fixed to the sediment by nails or sediment screws. The sensor head is equipped with an "inverted tipping-bucket" sensor, which basically works like a turned upside-down rain gauge. It fills with the collected gas until full, then empties completely and starts again, which allows the calculation of the flow rate by container volume and frequency of the cycle. This sensor type is very robust due to a design nearly without moving parts and suitable for very low to medium flow rates. For higher flow rates different sensor heads using turbine wheels or pressure differences can be used. The pressure housing for this prototype is made of aluminium and contains a Hobo Pendant data logger with integrated battery supply. Since this setup is inexpensive, it can be deployed in numbers to cover larger areas. By addition of multi-channel data loggers, data transmission by acoustic modem or cable, relay stations on the seafloor or buoys etc. the infrastructure can be adapted to the environmental setting and financial budget. Prototype tests under laboratory conditions as well as field tests on natural submarine gas vents as an analogue to leaking storage sites have demonstrated the capabilities and robustness of the systems.

  10. High Speed Submarine Optical Fiber Communication System:Pressure and Temperature Effects

    Directory of Open Access Journals (Sweden)

    A. A. Mohammed


    Full Text Available In the present paper, the performance of high speed submarine optical fiber cable systems is investigated, taking into account both the pressure and the temperature effects. Both the pressure and the temperature are depth-dependent variables, while both the spectral losses and the dispersion effects are temperature as well as wavelength dependent variables. Two important cases with real fibers are processed: a case with dispersion cancellation and a case without dispersion cancellation. It is found that the ocean pressure (due to the depth shifts the dispersion-free wavelength towards the third communication window. In general, as the depth increases the maximum transmitted bit rate increases in the range of interest. The system capacity as well as the spectral losses, and the dispersion effects are parametrically investigated over wide-range ranges of the set of affecting parameters {wavelength, ocean depth (and consequently the ocean pressure and temperature, and the chemical structure}. Key Words: Submarine Optical Fiber, Undersea Optical Communication, Pressure and Temperature Effects, Transoceanic Optical Communications

  11. Data Base On Cables And Connectors (United States)

    Bowen, Arlen R.; Oliver, John D.


    Report describes Connector Adapter Cable Information Data Base (CONNAID) computer program, managing data base containing necessary information concerning electrical connectors, breakout boxes, adapter cables, backshells, and pertinent torque specifications for engineering project.

  12. Equalization of data transmission cable (United States)

    Zobrist, G. W.


    The paper describes an equalization approach utilizing a simple RLC network which can obtain a maximum slope of -12dB/octave for reshaping the frequency characteristics of a data transmission cable, so that data may be generated and detected at the receiver. An experimental procedure for determining equalizer design specifications using distortion analysis is presented. It was found that for lengths of 16 PEV-L cable of up to 5 miles and data transmission rates of up to 1 Mbs, the equalization scheme proposed here is sufficient for generation of the data with acceptable error rates.

  13. Online Cable Tester and Rerouter (United States)

    Lewis, Mark; Medelius, Pedro


    Hardware and algorithms have been developed to transfer electrical power and data connectivity safely, efficiently, and automatically from an identified damaged/defective wire in a cable to an alternate wire path. The combination of online cable testing capabilities, along with intelligent signal rerouting algorithms, allows the user to overcome the inherent difficulty of maintaining system integrity and configuration control, while autonomously rerouting signals and functions without introducing new failure modes. The incorporation of this capability will increase the reliability of systems by ensuring system availability during operations.

  14. Status and Progress of a Fault Current Limiting Hts Cable to BE Installed in the con EDISON Grid (United States)

    Maguire, J.; Folts, D.; Yuan, J.; Henderson, N.; Lindsay, D.; Knoll, D.; Rey, C.; Duckworth, R.; Gouge, M.; Wolff, Z.; Kurtz, S.


    In the last decade, significant advances in the performance of second generation (2G) high temperature superconducting wire have made it suitable for commercially viable applications such as electric power cables and fault current limiters. Currently, the U.S. Department of Homeland Security is co-funding the design, development and demonstration of an inherently fault current limiting HTS cable under the Hydra project with American Superconductor and Consolidated Edison. The cable will be approximately 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The underground cable will be installed and energized in New York City. The project is led by American Superconductor teamed with Con Edison, Ultera (Southwire and nkt cables joint venture), and Air Liquide. This paper describes the general goals, design criteria, status and progress of the project. Fault current limiting has already been demonstrated in 3 m prototype cables, and test results on a 25 m three-phase cable will be presented. An overview of the concept of a fault current limiting cable and the system advantages of this unique type of cable will be described.

  15. Trenchless Replacement of Buried Cable Lines

    Directory of Open Access Journals (Sweden)

    Hans-Joachim Bayer


    Full Text Available An enormous amount of underground electricity and telecommunication cables have been worn over the time with technical defects or need capacity increases. Thus, new lines need to be installed. In urban areas, even in smaller communities and in natural reserves, open trenching is difficult and often not permitted.In response, new patented methods of trenchless cable replacement using the HDD equipment have been developed by the TT Group. The new technology is called “Wash-over-cable-replacement” and applies specially designed drill heads, cutting around the old cable string in various configurations (completely closed, U-shape or S-shape embracing, depending to the coating type of the old cable. This special cable replacement drill head separates the cable from the surrounding adhesive soil or the sand bedding by creating a very small annular space around the cable thus enabling the pulling or dragging out of the old cable section between the start and the exit pit. After the old cable has been loosened from the surrounding soil by means of the wash over process and pulled out, the new cable can be smoothly pulled into the void using the drill rods and embedding the new cable in a rich bed of Bentonite.The wash-over drill heads are slim and have inner and outer nozzles for Bentonite and bits to handle roots, pebbles, gravel and the like. These drill heads perform very quickly (up to 3 meters per minute to effectively wash over existing cables without damaging the cable coating and prepare the ground for a fast new laying of a new cable in the existing line. Network owners also benefit from the fact that new geodetic or topographic surveys and documentations of the new cable are not necessary. Only the documents, remarks, technical codes and existing geodetic data need to be updated.The paper will outline the technological background and include several practical job examples.

  16. Research on the video detection device in the invisible part of stay cable anchorage system (United States)

    Cai, Lin; Deng, Nianchun; Xiao, Zexin


    The cables in anchorage zone of cable-stayed bridge are hidden within the embedded pipe, which leads to the difficulty for detecting the damage of the cables with visual inspection. We have built a detection device based on high-resolution video capture, realized the distance observing of invisible segment of stay cable and damage detection of outer surface of cable in the small volume. The system mainly consists of optical stents and precision mechanical support device, optical imaging system, lighting source, drived motor control and IP camera video capture system. The principal innovations of the device are ⑴A set of telescope objectives with three different focal lengths are designed and used in different distances of the monitors by means of converter. ⑵Lens system is far separated with lighting system, so that the imaging optical path could effectively avoid the harsh environment which would be in the invisible part of cables. The practice shows that the device not only can collect the clear surveillance video images of outer surface of cable effectively, but also has a broad application prospect in security warning of prestressed structures.

  17. Integrated Cable System Aging Management Guidance: Low-Voltage Cable

    Energy Technology Data Exchange (ETDEWEB)

    Denny, W M


    The document provides insights into common aging issues and symptoms and includes pictures and descriptions of deterioration that is observable. The report provides a rapid review of the important information necessary to assess the aging of the low-voltage cable system used in nuclear power plants.

  18. Using Cable Television for Library Data Transmission. (United States)

    Whitaker, Douglas A.


    Discusses information gained from a test of cable data circuits on a Geac bibliographic control system at the Wayne Oakland Library Federation (WOLF) (Michigan). Highlights include an introduction to cable, hardware profile, the WOLF experience, and key questions that will affect the future use of cable for data transmission. (EJS)

  19. Effects of EMF Emissions from Cables and Junction Boxes on Marine Species

    Energy Technology Data Exchange (ETDEWEB)

    Dhanak, Manhar [Florida Atlantic Univ., Boca Raton, FL (United States); Spieler, Richard [Nova Southeastern Univ., Fort Lauderdale, FL (United States); Kilfoyle, Kirk [Nova Southeastern Univ., Fort Lauderdale, FL (United States); Jermain, Robert F. [Nova Southeastern Univ., Fort Lauderdale, FL (United States); Frankenfield, John [Florida Atlantic Univ., Boca Raton, FL (United States); Ravenna, Shirley [Florida Atlantic Univ., Boca Raton, FL (United States); Dibiasio, Christopher [Florida Atlantic Univ., Boca Raton, FL (United States); Coulson, Robert [Florida Atlantic Univ., Boca Raton, FL (United States); Henderson, Ed [Florida Atlantic Univ., Boca Raton, FL (United States); Venezia, William [Naval Surface Warfare Center (NSWC), Carderock Division (United States)


    Studies have shown that diverse aquatic species are electrosensitive. Many fishes, and marine mammals, can either detect, navigate by, or are affected by electromagnetic fields (EMF) with various sensitivities, and their behavior may be impacted by unnatural EMF emissions in the water column. Sharks, rays and skates are known to have the highest sensitivity to electric fields. Electric field emissions in the range 0.5–100 micro volt/m appear to attract them, and emissions over 100 micro volt/m to repulse them. A marine hydrokinetic MHK device will have multiple components and associated multiple submarine cables on the seafloor and running through the water column and would potentially increase the level of EMF emissions to which the marine species at the site may be exposed to. There are therefore concerns amongst stakeholders that EMF emissions associated with MHK devices and their components may act as barriers to species migration, cause disorientation, change community compositions and ecosystems, and that they may attract sharks, leading to a local increase in the risk of shark attacks. However, field data to validate and model potential relationships between observed responses and the EMF emissions in situ are sparse. A program of experimental field surveys were conducted off the coast of South Florida, USA to characterize the electromagnetic field (EMF) emissions in the water column from a submarine cable, and to monitor for responses of local aquatic species. The field surveys were conducted at the South Florida Ocean Measurement Facility (SFOMF) off Fort Lauderdale, which is a cabled offshore in-water navy range. It consists of multiple active submarine power cables and a number of junction boxes, with the capability to transmit AC/DC power at a range of strength and frequencies. The site includes significant marine life activities and community structure, including highly mobile species, such as sharks, stingrays, mammals and turtles. SFOMF therefore

  20. Simulation on Temperature and Ampacity of Mining Flame-proof High Voltage Cable Connector

    Directory of Open Access Journals (Sweden)

    Li Haiying


    Full Text Available To investigate the accident causes of mining flame-proof high voltage (F-HV cable connector, the temperature and ampacity of LBG1-200/6 high voltage cable connector are analyzed. At first, the material properties and structure of connector are introduced from the aspects of electrical, insulation and thermal. Then the electromagnetic field and thermal field coupling model of cable connector are established by the finite element method. Finally, in the numerical examples, temperature distribution and ampacity change caused by power harmonics, dielectric loss and slight structure change are quantitatively plotted and analyzed. The paper provides great insight into the security operation of F-HV cable connector.

  1. Psychological Implications for Submarine Display Design (United States)


    This paper addresses a number of psychological issues pertaining to display design . We review the literature comparing 3-D and 2-D displays and...perceptual, cognitive and ecological factors that are relevant to display design for submarine environments. The Generative Transformational visual perception is outlined and the relevance of transformational theory to display design is discussed. The paper also discusses a number of

  2. Topology Model of the Flow around a Submarine Hull Form (United States)


    resistance and flow noise arising from flow-structure interaction, it is necessary to test the shape of the submarine , which includes the length-to...UNCLASSIFIED Topology Model of the Flow around a Submarine Hull Form S.-K. Lee Maritime Division Defence Science and Technology Group DST-Group–TR...3177 ABSTRACT A topology model constructed from surface-streamer visualisation describes the flow around a generic conventional submarine hull form at

  3. A Lanchester model of submarine attack on a carrier battlegroup


    Eagle, James N.


    A Lanchester model is developed for a battlegroup ASW engagement. Two variations are included. In the first, long-range missile firing submarines, short-range missile or torpedo firing submarines, and submarines firing only torpedoes distribute their attack uniformly over battlegroup escort ships and carriers. In the second variation, the attack is concentrated on the carriers. supported by the Naval War College NA

  4. Cable Television and Satellite Broadcasting (United States)


    homes by the end teevision per week. However, accorigtthIne op that de a ay anthr 4 million hoesby - tohoe pendent Broadcast Authority’s (IBA...France to create a leisure desire to buy cable TV. park and a production studio for cartoons. 8 The Role of Public Service Providers In the Next Decade

  5. Power applications for superconducting cables

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Hansen, Steen; Jørgensen, Preben


    High temperature superconducting (HTS) cables for use in electric ac power systems are under development around the world today. There are two main constructions under development: the room temperature dielectric design and the cryogenic dielectric design. However, theoretical studies have shown...

  6. Parallel monostrand stay cable bending fatigue

    DEFF Research Database (Denmark)

    Winkler, Jan Pawel

    of a cable stayed bridge. Characterization of a bridge monitoring data is shown and a generic method for the analysis of a cable fatigue in cable supported bridge structure is proposed. With this research, one of the most basic oversights in the lifetime assessment of cablesupported structures, namely......This dissertation investigates the bending fatigue response of high-strength steel monostrands and multistrand stay cables to cyclic transverse deformations. Increasing bridge stock numbers and a push for longer cable-supported span lengths have led to an increased number of reported incidents...... of damage and replacement of bridge stay cables due to wind and traffic-induced fatigue. The understanding of fatigue mechanisms in most steel structures is well established. However, in the case of cables composed of steel strands, many important aspects related with bending fatigue remain to be clarified...

  7. Meta-Analysis of Data from the Submarine Ventilation Doctrine Test Program

    National Research Council Canada - National Science Library

    Hoover, J


    .... The Submarine Ventilation Doctrine Test Program was developed to address submarine-specific issues regarding the use of ventilation systems to control smoke and heat movement, maintain habitability...

  8. New method for the detection and monitoring of subsea power cable (United States)

    Held, Philipp; Schneider, Jens; Feldens, Peter; Wilken, Dennis


    Marine renewable energy farms, no matter what kind of, have in common that they need a connection with the onshore power grid. Thus, not only their offshore generation facilities could have impacts on the surrounding environment, but also associated submarine power cables. These cables have to be buried in the seabed - at least in coastal heavy shipping environments - for safety reasons. Cable laying disturbs the local seafloor and the sub-bottom. Refillment of dredged sediments are expected softer than the original material and could be washed away by currents. Therefore, buried cables have to be repeatedly monitored to ensure their burial depth. This study presents a new method for efficient cable detection. A parametric echosounder system using 15 kHz as secondary frequency was adapted to investigate the angular response of sub-bottom backscatter strength of layered mud and to introduce a new method for enhanced acoustic detection of buried targets. Adaptations to achieve both vertical (0°) and non-vertical inclination of incident sound on the seabed (1-15°, 30°, 45°, and 60°) comprise mechanical tilting of the acoustic transducer and electronic beam steering. A sample data set was acquired at a study site at 18 m water depth and a flat and muddy seafloor. At this site, a 0.1 m diameter power cable is buried 1-2 m below the sea floor. Surveying the cable with vertical incidence revealed that the buried cable can hardly be discriminated against the backscatter strength of the layered mud. However, the backscatter strength of layered mud was found to strongly decrease at >3±0.5° incidence and the layered mud echo pattern vanished beyond 5°. As a consequence the visual recognition of the cable echo in acoustic images improves for higher incidence angles of 15°, 30°, 45°, and 60°. Data analysis support this visual impression. The size of the cable echo pattern was found to linearly increase with incidence, whereas the signal-to-noise ratio peaks at about

  9. 49 CFR 1580.201 - Rail security coordinator. (United States)


    ... 49 Transportation 9 2010-10-01 2010-10-01 false Rail security coordinator. 1580.201 Section 1580... ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY MARITIME AND LAND TRANSPORTATION SECURITY RAIL TRANSPORTATION..., including heavy rail transit, light rail transit, automated guideway, cable car, inclined plane, funicular...

  10. Australia’s Submarine Design Capabilities and Capacities: Challenges and Options for the Future Submarine (United States)


    General Dynamics Electric Boat Corporation EMC electromagnetic compatibility EMF electromagnetic field EMI electromagnetic interference EPCM flow-induced radiated noise Own-sensor performance degradation Note: Risks can be reduced for given designs using scale models...Acoustic analysis Addresses the total radiated noise signature of submarine designs Radiated noise that an enemy might detect Self-noise that that

  11. New compact ocean bottom cabled seismometer system deployed in the Japan Sea (United States)

    Shinohara, Masanao; Kanazawa, Toshihiko; Yamada, Tomoaki; Machida, Yuya; Shinbo, Takashi; Sakai, Shin'ichi


    The Japanese islands are positioned near the subduction zones, and large earthquakes have repeatedly occurred in marine areas around Japan. However, the number of permanent earthquake observatories in the oceans is quite limited. It is important for understanding generation of large earthquakes to observe seismic activities on the seafloor just above these seismogenic zones. An ocean bottom cabled seismometer (OBCS) is the best solution because data can be collected in real-time. We have developed a new compact OBCS system. A developed system is controlled by a microprocessor, and signals from accelerometers are 24-bit digitized. Clock is delivered from the global positioning system receiver on a landing station using a simple dedicated line. Data collected at each cabled seismometer (CS) are transmitted using standard Internet Protocol to landing stations. The network configuration of the system adopts two dual methods. We installed the first practical OBCS system in the Japan Sea, where large earthquakes occurred in past. The first OBCS system has a total length of 25 km and 4 stations with 5 km interval. Installation was carried out in August 2010. The CSs and single armored optical submarine cable were buried 1 m below the seafloor to avoid a conflict with fishing activity. The data are stored on a landing station and sent to Earthquake Research Institute, University of Tokyo by using the Internet. After the installation, data are being collected continuously. According to burial of the CSs, seismic ambient noises are smaller than those observed on seafloor.

  12. Tubing and cable cutting tool (United States)

    Mcsmith, D. D.; Richardson, J. I. (Inventor)


    A hand held hydraulic cutting tool was developed which is particularly useful in deactivating ejection seats in military aircraft rescue operations. The tool consists primarily of a hydraulic system composed of a fluid reservoir, a pumping piston, and an actuator piston. Mechanical cutting jaws are attached to the actuator piston rod. The hydraulic system is controlled by a pump handle. As the pump handle is operated the actuator piston rod is forced outward and thus the cutting jaws are forced together. The frame of the device is a flexible metal tubing which permits easy positioning of the tool cutting jaws in remote and normally inaccessible locations. Bifurcated cutting edges ensure removal of a section of the tubing or cable to thereby reduce the possibility of accidental reactivation of the tubing or cable being severed.

  13. The 1929 Grand Banks submarine landslide revisited (United States)

    Schulten, Irena; Mosher, David C.; Krastel, Sebastian; Piper, David J. W.; Kienast, Markus


    On November 18th, 1929 a large submarine landslide occurred along the St. Pierre Slope of the southwestern Grand Banks of Newfoundland, as a result of a Mw 7.2 earthquake. This submarine landslide led to the first recognition of naturally-occurring submarine turbidity currents and is one of the few landslides known to have generated a tsunami. The event caused 28 causalities in Newfoundland and severe infrastructural damage. Earlier investigations of the area identified widely distributed shallow mass failures (15 - 20 m high escarpments), but no evidence of a larger headscarp. It is difficult to conceive, therefore, how this distributed shallow failure that rapidly evolved into a turbidity current would have generated a tsunami. It is hypothesised in this study that a deeper rooted sediment failure ( 500 m), involving faulting and mass-rotation, was involved in the sediment failure and this displacement generated the tsunami. In order to test this hypothesis, the volume and kinematics of the 1929 slope failure are analysed by means of recently acquired high resolution seismic reflection and multibeam swath bathymetry data, in addition to a significant volume of legacy data. The data allow determination of: 1) the dimension of the failure area, 2) the thickness and volume of failed sediment on St. Pierre Slope, 3) fault patterns and displacements, and 4) styles of sediment failure involved. Shallow (20 m high) sinuous escarpments and a number of faults are observed along the upper St. Pierre Slope (500 - 2 500 m water depth). The uppermost and largest of these escarpments shows association with a fault system. Preliminary results, therefore, indicate a complex sediment failure pattern along the St. Pierre Slope, possibly involving a deep-seated decollement and mobilization of a large volume of surficial sediment through retrogressive failure. Causes for the tsunami are yet to be determined.

  14. Multivariable Control System Design for a Submarine, (United States)


    perturbations applied to the nominal point were identical in all cases (see table 2.3). The comparisons show excellent correlation between the...Open Loop Singular Values for the 5 and 1S Knot Linear Modelo *~~* b % % V’ , * % ~ .%~ C 9 ~ V. --.- V. V.-.--.--46..- S. 77’ Model S20R5 20- 10- -0...without imparting a pitch angle to the submarine and provides an excellent example of both the usefulness of w(t) as a state variable and the

  15. Hydrogen isotope systematics of submarine basalts (United States)

    Kyser, T.K.; O'Neil, J.R.


    The D/H ratios and water contents in fresh submarine basalts from the Mid-Atlantic Ridge, the East Pacific Rise, and Hawaii indicate that the primary D/H ratios of many submarine lavas have been altered by processes including (1) outgassing, (2) addition of seawater at magmatic temperature, and (3) low-temperature hydration of glass. Decreases in ??D and H2O+ from exteriors to interiors of pillows are explained by outgassing of water whereas inverse relations between ??D and H2O+ in basalts from the Galapagos Rise and the FAMOUS Area are attributed to outgassing of CH4 and H2. A good correlation between ??D values and H2O is observed in a suite of submarine tholeiites dredged from the Kilauea East Rift Zone where seawater (added directly to the magma), affected only the isotopic compositions of hydrogen and argon. Analyses of some glassy rims indicate that the outer millimeter of the glass can undergo lowtemperature hydration by hydroxyl groups having ??D values as low as -100. ??D values vary with H2O contents of subaerial transitional basalts from Molokai, Hawaii, and subaerial alkali basalts from the Society Islands, indicating that the primary ??D values were similar to those of submarine lavas. Extrapolations to possible unaltered ??D values and H2O contents indicate that the primary ??D values of most thoteiite and alkali basalts are near -80 ?? 5: the weight percentages of water are variable, 0.15-0.35 for MOR tholeiites, about 0.25 for Hawaiian tholeiites, and up to 1.1 for alkali basalts. The primary ??D values of -80 for most basalts are comparable to those measured for deep-seated phlogopites. These results indicate that hydrogen, in marked contrast to other elements such as Sr, Nd, Pb, and O, has a uniform isotopic composition in the mantle. This uniformity is best explained by the presence of a homogeneous reservoir of hydrogen that has existed in the mantle since the very early history of the Earth. ?? 1984.

  16. Science requirements and the design of cabled ocean observatories

    Directory of Open Access Journals (Sweden)

    H. Mikada


    Full Text Available The ocean sciences are beginning a new phase in which scientists will enter the ocean environment and adaptively observe the Earth-Ocean system through remote control of sensors and sensor platforms. This new ocean science paradigm will be implemented using innovative facilities called ocean observatories which provide unprecedented levels of power and communication to access and manipulate real-time sensor networks deployed within many different environments in the ocean basins. Most of the principal design drivers for ocean observatories differ from those for commercial submarine telecommunications systems. First, ocean observatories require data to be input and output at one or more seafloor nodes rather than at a few land terminuses. Second, ocean observatories must distribute a lot of power to the seafloor at variable and fluctuating rates. Third, the seafloor infrastructure for an ocean observatory inherently requires that the wet plant be expandable and reconfigurable. Finally, because the wet communications and power infrastructure is comparatively complex, ocean observatory infrastructure must be designed for low life cycle cost rather than zero maintenance. The origin of these differences may be understood by taking a systems engineering approach to ocean observatory design through examining the requirements derived from science and then going through the process of iterative refinement to yield conceptual and physical designs. This is illustrated using the NEPTUNE regional cabled observatory power and data communications sub-systems.

  17. Initial tension loss in cerclage cables. (United States)

    Ménard, Jérémie; Émard, Maxime; Canet, Fanny; Brailovski, Vladimir; Petit, Yvan; Laflamme, George Y


    Cerclage cables, frequently used in the management of fractures and osteotomies, are associated with a high failure rate and significant loosening during surgery. This study compared the capacity to maintain tension of different types of orthopaedic cable systems. Multifilament Cobalt-Chrome (CoCr) cables with four different crimp/clamp devices (DePuy, Stryker, Zimmer and Smith&Nephew) and one non-metallic Nylon (Ny) cable from Kinamed were instrumented with a load cell to measure tension during insertion. Significant tension loss was observed with crimping for all cables (Ptensioner led to an additional unexpected tension loss (CoCr-DePuy: 18%, CoCr-Stryker: 29%, CoCr-Smith&Nephew: 33%, Ny: 46%, and CoCr-Zimmer: 52%). The simple CoCr (DePuy) cable system outperformed the more sophisticated locking devices due to its significantly better ability to prevent tension loss. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Field application of a cable NDT system for cable-stayed bridge using MFL sensors integrated

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ju Won; Choi, Jun Sung; Park, Seung Hee [Sungkyunkwan University, Seoul (Korea, Republic of); Lee, Eun Chan [Korea Maintance Co., Ltd., Seoul (Korea, Republic of)


    In this study, an automated cable non-destructive testing(NDT) system was developed to monitor the steel cables that are a core component of cable-stayed bridges. The magnetic flux leakage(MFL) method, which is suitable for ferromagnetic continuum structures and has been verified in previous studies, was applied to the cable inspection. A multi-channel MFL sensor head was fabricated using hall sensors and permanent magnets. A wheel-based cable climbing robot was fabricated to improve the accessibility to the cables, and operating software was developed to monitor the MFL-based NDT research and control the climbing robot. Remote data transmission and robot control were realized by applying wireless LAN communication. Finally, the developed element techniques were integrated into an MFL-based cable NDT system, and the field applicability of this system was verified through a field test at Seohae Bridge, which is a typical cable-stayed bridge currently in operation.

  19. Fatigue of cable anchorage of large cable stayed bridge; Daikibo shachokyo cable teichaku kozo no hiro

    Energy Technology Data Exchange (ETDEWEB)

    Endo, T.; Matsumoto, T. [Honshu-Shikoku Bridge Authority, Tokyo (Japan); Tsukahara, H. [Yokogawa Bridge Corp., Tokyo (Japan); Miki, C. [Tokyo Institute of Technology, Tokyo (Japan)


    Design considerations such as design schemes, the assemblage and welding of steel plates, and safety for fatigue of welded connections have to be taken for the cable anchorages of the steel cable stayed bridges. In this study, two full scale models, which have different shape of box anchorages welded to the web of the main girder, were made to investigate fatigue characteristics as well as assemblage of plate and gelding details. Finite element analyses for both test models and actual bridges here carried out to compare stress distribution. It was confirmed that the assemblage and welding of both types of box anchorage were attainable kith required quality and accuracy. According to the fatigue test, fatigue cracks originated from the weldings of the bearing plate to which the load from cable socket applied directly were caused by out-of-plane bending of the bearing plate. It was proved that the slight modifications of the details around the bearing plate resulted in sufficient fatigue strength in both types of anchorage. 1 ref., 23 figs., 2 tabs.

  20. How do you like them cables?

    CERN Multimedia

    Sergei Malyukov

    Cabling work is not for clautrophobic people! Cables are like the blood vessels and nervous system of ATLAS. With the help of all these cables, we can power ATLAS, control the detector and read out the data. Like the human blood vessels, they penetrate inside the ATLAS volume, reaching each of its elements. The ATLAS developers started to think about design of services, cables and pipes at the very first stages of the project. The cabling project has been developing most intensively during the last five years, passing through the projection and CAD design phases, then the installation of cable trays and finally the cables. The cable installation itself took two and a half years and was done by teams of technicians from several institutes from Russia, the Czech Republic and Poland. Here are some numbers to illustrate the scale of the ATLAS cabling system. More than 25000 optical fiber channels are used for reading the information from the sub-detectors and delivering the timing signals. The total numbe...

  1. Managing cable thermal stress through predictive ratings


    Huang, R.; Pilgrim, J.A.; Lewin, P.L.; Scott, D.; Morrice, D.


    The majority of high voltage cables are sized and operated by a continuous current rating which is based on the worst-case assumptions. However, the load on the cables themselves may vary significantly depending upon the time and season. In this paper, a dynamic thermal model for a cable in air installation is built using the finite difference method. The real-time load current and ambient conditions are accessible to allow improved cable modelling. This model is then used to support the rati...

  2. Flow dynamics around downwelling submarine canyons

    Directory of Open Access Journals (Sweden)

    J. M. Spurgin


    Full Text Available Flow dynamics around a downwelling submarine canyon were analysed with the Massachusetts Institute of Technology general circulation model. Blanes Canyon (northwestern Mediterranean was used for topographic and initial forcing conditions. Fourteen scenarios were modelled with varying forcing conditions. Rossby and Burger numbers were used to determine the significance of Coriolis acceleration and stratification (respectively and their impacts on flow dynamics. A new non-dimensional parameter (χ was introduced to determine the significance of vertical variations in stratification. Some simulations do see brief periods of upwards displacement of water during the 10-day model period; however, the presence of the submarine canyon is found to enhance downwards advection of density in all model scenarios. High Burger numbers lead to negative vorticity and a trapped anticyclonic eddy within the canyon, as well as an increased density anomaly. Low Burger numbers lead to positive vorticity, cyclonic circulation, and weaker density anomalies. Vertical variations in stratification affect zonal jet placement. Under the same forcing conditions, the zonal jet is pushed offshore in more uniformly stratified domains. The offshore jet location generates upwards density advection away from the canyon, while onshore jets generate downwards density advection everywhere within the model domain. Increasing Rossby values across the canyon axis, as well as decreasing Burger values, increase negative vertical flux at shelf break depth (150 m. Increasing Rossby numbers lead to stronger downwards advection of a passive tracer (nitrate, as well as stronger vorticity within the canyon. Results from previous studies are explained within this new dynamic framework.

  3. Submarine melt rates under Greenland's ice tongues (United States)

    Wilson, Nat; Straneo, Fiametta; Heimbach, Patrick; Cenedese, Claudia


    The few remaining ice tongues (ice-shelf like extensions) of Greenland's glaciers are undergoing rapid changes with potential implications for the stability of the ice sheet. Submarine melting is recognized as a major contributor to mass loss, yet the magnitude and spatial distribution of melt are poorly known or understood. Here, we use high resolution satellite imagery to infer the magnitude and spatial variability of melt rates under Greenland's largest remaining ice tongues: Ryder Glacier, Petermann Glacier and Nioghalvfjerdsbræ (79 North Glacier). We find that submarine plus aerial melt approximately balance the ice flux from the grounded ice sheet for the first two while at Nioghalvfjerdsbræ the total melt flux exceeds the inflow of ice indicating thinning of the ice tongue. We also show that melt rates under the ice tongues vary considerably, exceeding 60 m yr-1 near the grounding zone and decaying rapidly downstream. Channels, likely originating from upstream subglacial channels, give rise to large melt variations across the ice tongues. Using derived melt rates, we test simplified melt parameterizations appropriate for ice sheet models and find the best agreement with those that incorporate ice tongue geometry in the form of depth and slope.

  4. Finite element analysis and static load test for guyed form traveller of cable-stayed bridge (United States)

    Ye, Xijun; Chen, Bingcong; Sun, Zhuo


    To ensure the security of the cantilever construction and elevation template adjustment for cable-stayed bridge, finite element model of guyed form traveller of Gan-zhu-xi cable-stayed bridge was built. At first, two models are considered under actual construction stage, then a static load test was carried out. The theoretic result was in consistent with the results from field test. It also showed that the optimal design was reliable and the operational performance could meet the construction requirements. Elevation template can be determined by the deflection measured results.

  5. Landing Marine-derived Renewable Energy: Optimising Power Cable Routing in the Nearshore Environment (United States)

    Turner, Rosalind, ,, Dr.; Keane, Tom; Mullins, Brian; Phipps, Peter


    estuary. Such difficulties include limited availability of superficial sediments for cable trenching and protection; where sediments were present there were indications that the sediments were either mobile sands, or difficult to trench glacial tills. Areas of the estuary feature steep side slopes and rocky outcrops, which also provide a challenge for cable installation and long-term protection. Difficult ground conditions were set against an aggressive meteo-oceanographic environment, tidal currents reached 5-7 knots on the ebb tide with reverse eddies around the landfalls coupled with an active wave climate. These conditions pose implications on the working time, installation vessels and methodology. The estuary is also a designated Special Area of Conservation for the protection of bottlenose dolphins, therefore, the cable installation methodology needed to consider ecological sensitivities. Additionally, an area near to the southern landfall has historically been an area of strategic significance and has a number of fortifications adding archaeological constraints for the cable route. The increasing need and importance of investigation and planning for submarine cable routes will be discussed alongside potential methods for installation in the aggressive nearshore environment, this paper will summarise findings and observations of working in a high energy environment, will consider options for installation and protection of cables, will discuss the key lessons learned and look at potential implications for offshore electricity generation.

  6. Cable fire tests in France

    Energy Technology Data Exchange (ETDEWEB)

    Kaercher, M. [Electricite de France (EDF), 69 - Villeurbanne (France)


    Modifications are being carried out in all French nuclear power plants to improve fire safety. These modifications are based on a three level defense in depth concept: fire preventing, fire containing and fire controlling. Fire containing requires many modifications such as protection of cable races and assessment of fire propagation which both need R and D development. On one hand, cable wraps made with mineral wool were tested in all configurations including effect of aging, overheating and fire and qualified for the use as protection from common failure modes. On the other hand, cables races in scale one were subject to gas burner or solvent pool fire to simulate ignition and fire propagation between trays and flash over situations. These tests have been performed under several typical lay out conditions. The results of the tests can be used as input data in computer modelling for validation of fire protection measures. (orig.) [German] Modifikationen werden in allen franzoesischen Kernkraftwerken durchgefuehrt, um die Brandschutzsicherung zu verbessern. Die Modifikationen sind auf einem Dreistufenkonzept begruendet: brandvorbeugende Massnahmen, begrenzter Brandschutz und Brandkontrolle. Begrenzter Brandschutz verlangt viele Modifikationen wie Brandschutz von Kabelanlagen und Kenntnisse ueber Feuerentwicklung, die Forschung und Entwicklung brauchen. Einerseits werden die aus Mineralwolle hergestellten Kabelhuellen fuer alle moeglichen Faelle geprueft, einschliesslich der Auswirkung von Alterung, Ueberhitzung und Feuer, um so die Huellen als Schutz zu nutzen. Andererseits werden Kabelanlagen der Stufe eins mit Gas und Loesungsmitteln entzuendet, um Entzuendung, Feuerentwicklung und Feueruebersprung zu simulieren. Diese Versuche werden unter unterschiedlichen Anlagenbedingungen durchgefuehrt. Die Ergebnisse koennen fuer Computermodelle zur Pruefung von Brandschutztechniken benutzt werden. (orig.)

  7. POTS to broadband ... cable modems. (United States)

    Kabachinski, Jeff


    There have been 3 columns talking about broadband communications and now at the very end when it's time to compare using a telco or cableco, I'm asking does it really matter? So what if I can actually get the whole 30 Mbps with a cable network when the website I'm connecting to is running on an ISDN line at 128 Kbps? Broadband offers a lot more bandwidth than the connections many Internet servers have today. Except for the biggest websites, many servers connect to the Internet with a switched 56-Kbps, ISDN, or fractional T1 line. Even with the big websites, my home network only runs a 10 Mbps Ethernet connection to my cable modem. Maybe it doesn't matter that the cable lines are shared or that I can only get 8 Mbps from an ADSL line. Maybe the ISP that I use has a T1 line connection to the Internet so my new ADSL modem has a fatter pipe than my provider! (See table 1). It all makes me wonder what's in store for us in the future. PC technology has increased exponentially in the last 10 years with super fast processor speeds, hard disks of hundreds of gigabytes, and amazing video and audio. Internet connection speeds have failed to keep the same pace. Instead of hundreds of times better or faster--modem speeds are barely 10 times faster. Broadband connections offer some additional speed but still not comparable growth as broadband connections are still in their infancy. Rather than trying to make use of existing communication paths, maybe we need a massive infrastructure makeover of something new. How about national wireless access points so we can connect anywhere, anytime? To use the latest and fastest wireless technology you will simply need to buy another $9.95 WLAN card or download the latest super slick WLAN compression/encryption software. Perhaps it is time for a massive infra-restructuring. Consider the past massive infrastructure efforts. The telcos needed to put in their wiring infrastructure starting in the 1870s before telephones were useful to the

  8. Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine Program: Background and Issues for Congress (United States)


    propulsion technology first occurred many years ago: To help jumpstart the UK’s nuclear - powered submarine program, the United States transferred to the UK a... nuclear - powered attack submarines (SSNs), nuclear - powered cruise missile submarines (SSGNs), and nuclear - powered ballistic missile submarines (SSBNs). 2...2 In the designations SSN, SSGN, SSBN, and SSBN(X), the SS stands for submarine, N stands for nuclear - powered (meaning the ship is

  9. Submarine landside in the Bussol Graben: Structural and formation features (United States)

    Baranov, B. V.; Lobkovsky, L. I.; Dozorova, K. A.; Rukavishnikova, D. D.


    Analysis of geophysical data obtained during a study of the insular slope in the central Kuril‒Kamchatka Trench during projects Kuriles-2005 and Kuriles-2006 promoted by the Presidium of the Russian Academy of Sciences revealed a large submarine landslide in this area. The landslide, located at the bottom of the transverse valley confined to the Bussol l Graben, resulted from the failure of the northeastern wall of a graben composed of sedimentary material. It exceeds 35 km3 in size, representing one of the large submarine landslides discovered to date on the slope of the Kuril‒Kamchatka Trench in submarine canyonfan environments.

  10. Management of demand based inventory aboard submarine tenders servicing attack (SSN) submarines


    Ross, Timothy Joseph


    Approved for public release; distribution is unlimited. This thesis examines the computation of inventory levels based on demand history aboard Submarine Tenders that use the Shipboard Automated Data Processing System (SUADPS) for inventory control. The focus of the thesis was the workload and supply effectiveness issues associated with the processing of the SUADPS levels setting program. The objective of the thesis was to determine the effect on supply effectiveness and stock churn if the...

  11. A new multiconstraint method for determining the optimal cable stresses in cable-stayed bridges. (United States)

    Asgari, B; Osman, S A; Adnan, A


    Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM). The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  12. Nonlinear Analysis of Cable Vibration of a Multispan Cable-Stayed Bridge under Transverse Excitation

    Directory of Open Access Journals (Sweden)

    Kun Lin


    Full Text Available The nonlinear vibrations of cable in a multispan cable-stayed bridge subjected to transverse excitation are investigated. The MECS (multielements cable system model, where multielements per cable stay are used, is built up and used to analyze the model properties of the multispan cable-stayed bridges. Then, a simplified two-degrees-of-freedom (2-DOFs model, where the tower or the deck is reduced to a beam, is proposed to analyze the nonlinear dynamic behaviors of the beam and cable. The results of MECS model analysis show that the main tower in the multispan cable-stayed bridge is prone to the transverse vibration, and the local vibration of cables only has a little impact on the frequency values of the global modes. The results of simplified model analysis show that the energy can be transformed between the modes of the beam and cable when the nature frequencies of them are very close. On the other hand, with the transverse excitation changing, the cable can exhibit richer quasi-periodic or chaotic motions due to the nonlinear terms caused by the coupled mode between the beam and cable.

  13. A New Multiconstraint Method for Determining the Optimal Cable Stresses in Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    B. Asgari


    Full Text Available Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM. The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  14. Switching Restrikes in HVAC Cable Lines and Hybrid HVAC Cable/OHL Lines

    DEFF Research Database (Denmark)

    da Silva, Filipe Miguel Faria; Bak, Claus Leth; Balle Holst, Per


    The disconnection of HV underground cables may, if unsuccessful, originate a restrike in the circuit breaker, leading to high overvoltages, and potentially damaging the cable and near equipment. Due to the cable high capacitance and low resistance the voltage damping is slow, resulting, half...... a cycle after the disconnection, in a voltage of approximately 2 pu at the circuit breaker terminals. In case of restrike in that instant, it is theoretical possible to attain an overvoltage of 3 pu. The overvoltage can be even larger in hybrid cable-Overhead Lines (OHL), due to voltage magnifications...... in the junction point. This paper explains the phenomenon for pure cable lines and hybrid cable-OHL lines, and uses Denmark’s high voltage transmission grid, as planned for the year 2030, as test system. The accuracy of different cable models, and the number of substations from the transient event requiring...

  15. Wind-induced vibration of stay cables (United States)


    Cable-stayed bridges have become the form of choice over the past several decades for bridges in the medium- to long-span range. In some cases, serviceability problems involving large amplitude vibrations of stay cables under certain wind and rain co...

  16. 30 CFR 18.45 - Cable reels. (United States)


    ... constitute an integral part of a circuit for transmitting electrical energy. (d) Cable reels for shuttle cars... MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.45 Cable reels. (a) A self-propelled machine, that receives electrical energy through a portable...

  17. Pay Cable: A Viable Advertising Medium? (United States)

    Krugman, Dean M.; Barban, Arnold M.

    Cable television, which cannot only clarify local signals to weak signal areas but can also bring in distant signals to areas which have been receiving few signals, has the capacity to present special television programs to customers for extra fees. The number of pay cable subscribers is growing and industry projections are that it will reach 20…

  18. The Status of Cable Communications in Libraries. (United States)

    Kenney, Brigitte L.

    Librarians are and will be using cable television technologies to enhance and extend their services. While questions remain in regard to the technology itself, the health and viability of the industry, and government policy, librarians are seeing cable communications as an opportunity to gain credibility and visibility, and also as an extension of…

  19. When is hardwood cable logging economical? (United States)

    Chris B. LeDoux


    Using cable logging to harvest eastern hardwood logs on steep terrain can result in low production rates and high costs per unit of wood produced. Logging managers can improve productivity and profitability by knowing how the interaction of site-specific variables and cable logging equipment affect costs and revenues. Data from selected field studies and forest model...

  20. Assessment of sodium conductor distribution cable

    Energy Technology Data Exchange (ETDEWEB)



    The study assesses the barriers and incentives for using sodium conductor distribution cable. The assessment considers environmental, safety, energy conservation, electrical performance and economic factors. Along with all of these factors considered in the assessment, the sodium distribution cable system is compared to the present day alternative - an aluminum conductor system. (TFD)


    Bell, Jamie A.; Saikus, Christina E.; Ratnayaka, Kanishka; Barbash, Israel M.; Faranesh, Anthony Z.; Franson, Dominique N.; Sonmez, Merdim; Slack, Michael C.; Lederman, Robert J.; Kocaturk, Ozgur


    Purpose To develop an active delivery system that enhances visualization of nitinol cardiac occluder devices during deployment under real-time MRI. Materials and Methods We constructed an active delivery cable incorporating a loopless antenna and a custom titanium microscrew to secure the occluder devices. The delivery cable was tuned and matched to 50Ω at 64 MHz with the occluder device attached. We used real-time balanced SSFP in a wide-bore 1.5T scanner. Device-related images were reconstructed separately and combined with surface-coil images. The delivery cable was tested in vitro in a phantom and in vivo in swine using a variety of nitinol cardiac occluder devices. Results In vitro, the active delivery cable provided little signal when the occluder device was detached and maximal signal with the device attached. In vivo, signal from the active delivery cable enabled clear visualization of occluder device during positioning and deployment. Device release resulted in decreased signal from the active cable. Post-mortem examination confirmed proper device placement. Conclusions The active delivery cable enhanced the MRI depiction of nitinol cardiac occluder devices during positioning and deployment, both in conventional and novel applications. We expect enhanced visibility to contribute to effectiveness and safety of new and emerging MRI-guided treatments. PMID:22707441

  2. Frequency Dependent Losses in Transmission Cable Conductors

    DEFF Research Database (Denmark)

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


    and economical gain, such severe network changes necessitate correct estimation and optimisation of load conditions in the cable grid. Both IEC and IEEE have published standards for rating transmission cables' current carrying capacity. These standards are based on assumptions of a number of parameters......, such as thermal conditions in and around the cable, as well as the heat generated in conductors, screens, armours etc., taking into account proximity and skin effects. The work performed and presented in this paper is concerned with an improved determination of the losses generated in the conductor, by means...... of better calculation of the AC resistance of transmission cable conductors, in particular regarding higher frequencies. In this way, also losses under harmonics can be covered. Furthermore, the model is suitable for modelling of transient attenuation in high voltage cables. The AC resistance is calculated...

  3. Counter-balanced, multiple cable construction crane (United States)

    Mikulas, Martin M., Jr. (Inventor); Yang, Li-Farn (Inventor)


    The invention is a counter-balanced, multiple cable construction crane. The apparatus for hoisting payloads comprises a crane having a lifting means, the lifting means comprising an end effector means and three suspension means or cables. One end of each cable attaches to a different winding means located on the lifting means, and the other end of each cable attaches to a different point on the end effector, such that the three cables have a theoretical point of convergence with this point corresponding to the center of mass of the payload. Three controls command rotation of the winding means to a predetermined position. Accordingly, the crane provides precise and autonomous positioning of the payload without human guidance. The crane further comprises a counter-balancing means. Two controls position the counter-balancing means to offset the overturning moment which arises during the lifting of heavy payloads.

  4. Nuclear power plant cable materials :

    Energy Technology Data Exchange (ETDEWEB)

    Celina, Mathias C.; Gillen, Kenneth T; Lindgren, Eric Richard


    A selective literature review was conducted to assess whether currently available accelerated aging and original qualification data could be used to establish operational margins for the continued use of cable insulation and jacketing materials in nuclear power plant environments. The materials are subject to chemical and physical degradation under extended radiationthermal- oxidative conditions. Of particular interest were the circumstances under which existing aging data could be used to predict whether aged materials should pass loss of coolant accident (LOCA) performance requirements. Original LOCA qualification testing usually involved accelerated aging simulations of the 40-year expected ambient aging conditions followed by a LOCA simulation. The accelerated aging simulations were conducted under rapid accelerated aging conditions that did not account for many of the known limitations in accelerated polymer aging and therefore did not correctly simulate actual aging conditions. These highly accelerated aging conditions resulted in insulation materials with mostly inert aging processes as well as jacket materials where oxidative damage dropped quickly away from the air-exposed outside jacket surface. Therefore, for most LOCA performance predictions, testing appears to have relied upon heterogeneous aging behavior with oxidation often limited to the exterior of the cable cross-section a situation which is not comparable with the nearly homogenous oxidative aging that will occur over decades under low dose rate and low temperature plant conditions. The historical aging conditions are therefore insufficient to determine with reasonable confidence the remaining operational margins for these materials. This does not necessarily imply that the existing 40-year-old materials would fail if LOCA conditions occurred, but rather that unambiguous statements about the current aging state and anticipated LOCA performance cannot be provided based on

  5. Submarine thermal springs on the Galapagos Rift (United States)

    Corliss, J.B.; Dymond, J.; Gordon, L.I.; Edmond, J.M.; Von Herzen, R. P.; Ballard, Richard D.; Green, K.; Williams, D.; Bainbridge, A.; Crane, K.; Van Andel, T. H.


    The submarine hydrothermal activity on and near the Galápagos Rift has been explored with the aid of the deep submersible Alvin. Analyses of water samples from hydrothermal vents reveal that hydrothermal activity provides significant or dominant sources and sinks for several components of seawater; studies of conductive and convective heat transfer suggest that two-thirds of the heat lost from new oceanic lithosphere at the Galápagos Rift in the first million years may be vented from thermal springs, predominantly along the axial ridge within the rift valley. The vent areas are populated by animal communities. They appear to utilize chemosynthesis by sulfur-oxidizing bacteria to derive their entire energy supply from reactions between the seawater and the rocks at high temperatures, rather than photosynthesis

  6. Improved OTEC System for a Submarine Robot (United States)

    Chao, Yi; Jones, Jack; Valdez, Thomas


    An ocean thermal energy conversion (OTEC), now undergoing development, is a less-massive, more-efficient means of exploiting the same basic principle as that of the proposed system described in "Alternative OTEC Scheme for a Submarine Robot" (NPO-43500), NASA Tech Briefs, Vol. 33, No. 1 (January 2009), page 50. The proposed system as described previously would be based on the thawing-expansion/freezing-contraction behavior of a wax or perhaps another suitable phase-change material (PCM). The power generated by the system would be used to recharge the batteries in a battery- powered unmanned underwater vehicle [UUV (essentially, a small exploratory submarine robot)] of a type that has been deployed in large numbers in research pertaining to global warming. A UUV of this type travels between the ocean surface and depths, measuring temperature and salinity. At one phase of its operational cycle, the previously proposed system would utilize the surface ocean temperature (which lies between 15 and 30 C over most of the Earth) to melt a PCM that has a melting/freezing temperature of about 10 C. At the opposite phase of its operational cycle, the system would utilize the lower ocean temperature at depth (e.g., between 4 and 7 C at a depth of 300 m) to freeze the PCM. The melting or freezing would cause the PCM to expand or contract, respectively, by about 9 volume percent. The PCM would be contained in tubes that would be capable of expanding and contracting with the PCM. The PCM-containing tubes would be immersed in a hydraulic fluid. The expansion and contraction would drive a flow of the hydraulic fluid against a piston that, in turn, would push a rack-and-pinion gear system to spin a generator to charge a battery.

  7. Wind-induced cable vibrations and countermeasures of cables of PC cable-stayed bridge. PC syachokyo keburu no kaze ni yoru shindo to sono taisaku

    Energy Technology Data Exchange (ETDEWEB)

    Yoneda, M. (Kawada Industries Inc., Tokyo (Japan))


    In recent years, long span of cable-stayed bridges is remarkable. The wind-induced cable vibration called as line vibration and wake galloping was given as an important problem not only in the steel cable-stayed bridges but also in the PC cable-stayed bridges. The technical engineers in design of the cable-stayed bridges have many times to confront the problems on the vibration control of cables, it is considered that sufficient understand of the wind-induced vibration and countermeasures for cables of the PC cable-stayed bridges is necessary. Many reports on the countermeasure examples and trend of vibration control centred on cables of the cable-stayed bridges have been published. In this paper, the wind-induced vibration of cables in the cable-stayed bridges was reviewed, the examples of countermeasures of vibration control on cables in the PC cable-stayed bridges was mainly introduced. The remaining tasks and future prospects on vibration control of the PC cable-stayed bridges were described. 14 refs., 13 figs., 4 tabs.

  8. A model for tidewater glacier undercutting by submarine melting (United States)

    Slater, D. A.; Nienow, P. W.; Goldberg, D. N.; Cowton, T. R.; Sole, A. J.


    Dynamic change at the marine-terminating margins of the Greenland Ice Sheet may be initiated by the ocean, particularly where subglacial runoff drives vigorous ice-marginal plumes and rapid submarine melting. Here we model submarine melt-driven undercutting of tidewater glacier termini, simulating a process which is key to understanding ice-ocean coupling. Where runoff emerges from broad subglacial channels we find that undercutting has only a weak impact on local submarine melt rate but increases total ablation by submarine melting due to the larger submerged ice surface area. Thus, the impact of melting is determined not only by the melt rate magnitude but also by the slope of the ice-ocean interface. We suggest that the most severe undercutting occurs at the maximum height in the fjord reached by the plume, likely promoting calving of ice above. It remains unclear, however, whether undercutting proceeds sufficiently rapidly to influence calving at Greenland's fastest-flowing glaciers.

  9. Submarine Upward Looking Sonar Ice Draft Profile Data and Statistics (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of upward looking sonar draft data collected by submarines in the Arctic Ocean. It includes data from both U.S. Navy and Royal Navy...

  10. Virtual Reality Training System for a Submarine Command Center

    National Research Council Canada - National Science Library

    Maxwell, Douglas B


    The invention as disclosed is a system that uses a combined real and virtual display interaction methodology to generate the visual appearance of submarine combat control rooms and allow interaction...

  11. Studies on submarine control for periscope depth operations


    Tolliver, John V.


    Approved for public release; distribution in unlimited. Requirements for submarine periscope depth operations have been increased by integration with carrier battle groups, littoral operations, and contributions to joint surveillance. Improved periscope depth performance is therefore imperative. Submarine control personnel rely on a large number of analog gauges and indications. An integrated digital display system could enhance the ergonomics of the human control interface and display add...

  12. Exercise Aboard Attack Submarines: Rationale and New Options (United States)


    experience loss of physical fitness while underway. Bennett and co-workers (2) noted a 7% reduction of maximal oxygen consumption in non-exercising...Inc. designed and built a comprehensive resistance exercise device to help counteract muscle deconditioning during long term space flights (the SX... Physical activity aboard nuclear submarines as measured by pedometry. Groton: Naval Submarine Medical Research Laboratory, Report 1053, 1985, p. 12

  13. Are tilt measurements useful in detecting tsunamigenic submarine landslides?


    Sascha Brune; Andrey Babeyko; Stephan V. Sobolev


    Large submarine landslides can generate dangerous tsunamis. Because of their long-period signal, detection of landslides by common seismological methods is difficult. Here we suggest a method of detecting submarine landslides by using an array of land-based tiltmeters. The displacement of a large volume of sediments during landsliding produces a detectable elastic response of the lithosphere. We propose a technique to calculate this response and to invert for tsunami relevant parameters like ...

  14. The development of permafrost bacterial communities under submarine conditions (United States)

    Mitzscherling, Julia; Winkel, Matthias; Winterfeld, Maria; Horn, Fabian; Yang, Sizhong; Grigoriev, Mikhail N.; Wagner, Dirk; Overduin, Pier P.; Liebner, Susanne


    Submarine permafrost is more vulnerable to thawing than permafrost on land. Besides increased heat transfer from the ocean water, the penetration of salt lowers the freezing temperature and accelerates permafrost degradation. Microbial communities in thawing permafrost are expected to be stimulated by warming, but how they develop under submarine conditions is completely unknown. We used the unique records of two submarine permafrost cores from the Laptev Sea on the East Siberian Arctic Shelf, inundated about 540 and 2500 years ago, to trace how bacterial communities develop depending on duration of the marine influence and pore water chemistry. Combined with geochemical analysis, we quantified total cell numbers and bacterial gene copies and determined the community structure of bacteria using deep sequencing of the bacterial 16S rRNA gene. We show that submarine permafrost is an extreme habitat for microbial life deep below the seafloor with changing thermal and chemical conditions. Pore water chemistry revealed different pore water units reflecting the degree of marine influence and stages of permafrost thaw. Millennia after inundation by seawater, bacteria stratify into communities in permafrost, marine-affected permafrost, and seabed sediments. In contrast to pore water chemistry, the development of bacterial community structure, diversity, and abundance in submarine permafrost appears site specific, showing that both sedimentation and permafrost thaw histories strongly affect bacteria. Finally, highest microbial abundance was observed in the ice-bonded seawater unaffected but warmed permafrost of the longer inundated core, suggesting that permafrost bacterial communities exposed to submarine conditions start to proliferate millennia after warming.

  15. Cardiometabolic Health in Submariners Returning from a 3-Month Patrol

    Directory of Open Access Journals (Sweden)

    Heath G. Gasier


    Full Text Available Confined space, limited exercise equipment, rotating shift work and reduced sleep may affect cardiometabolic health in submariners. To test this hypothesis, 53 male U.S. Submariners (20–39 years were studied before and after a 3-month routine submarine patrol. Measures included anthropometrics, dietary and physical activity, biomarkers of cardiometabolic health, energy and appetite regulation, and inflammation. Before deployment, 62% of submariners had a body fat % (BF% ≥ 25% (obesity, and of this group, 30% met the criteria for metabolic syndrome. In obese volunteers, insulin, the homeostatic model assessment of insulin resistance (HOMA-IR, leptin, the leptin/adiponectin ratio, and pro-inflammatory chemokines growth-related oncogene and macrophage-derived chemokine were significantly higher compared to non-obese submariners. Following the patrol, a significant mean reduction in body mass (5% and fat-mass (11% occurred in the obese group as a result of reduced energy intake (~2000 kJ during the patrol; and, independent of group, modest improvements in serum lipids and a mean reduction in interferon γ-induced protein 10 and monocyte chemotactic protein 1 were observed. Since 43% of the submariners remained obese, and 18% continued to meet the criteria for metabolic syndrome following the patrol, the magnitude of weight loss was insufficient to completely abolish metabolic dysfunction. Submergence up to 3-months, however, does not appear to be the cause of obesity, which is similar to that of the general population.

  16. Solution of Supplee's submarine paradox through special and general relativity

    CERN Document Server

    Vieira, R S


    In 1989 Supplee described an apparent relativistic paradox on which a submarine seems to sink in a given frame while floating in another one. If the submarine density is adjusted to be the same as the water density (when both of them are at rest) and then it is put to move, the density of the submarine will become higher than that of the water, thanks to Lorentz contraction, and hence it sinks. However, in the submarine proper frame, is the water that becomes denser, so the submarine supposedly should float and we get a paradox situation. In this paper we analyze the submarine paradox in both a flat and a curved spacetime. In the case of a flat spacetime, we first show that any relativistic force field in special relativity can be written in the Lorentz form, so that it can always be decomposed into a static (electric-like) and a dynamic (magnetic-like) part. Taking into account the gravitomagnetic effects between the Earth and the water, a relativistic formulation of Archimedes principle can be established, ...

  17. Self-healing cable for extreme environments (United States)

    Huston, Dryver R. (Inventor); Tolmie, Bernard R. (Inventor)


    Self-healing cable apparatus and methods disclosed. The self-healing cable has a central core surrounded by an adaptive cover that can extend over the entire length of the self-healing cable or just one or more portions of the self-healing cable. The adaptive cover includes an axially and/or radially compressible-expandable (C/E) foam layer that maintains its properties over a wide range of environmental conditions. A tape layer surrounds the C/E layer and is applied so that it surrounds and axially and/or radially compresses the C/E layer. When the self-healing cable is subjected to a damaging force that causes a breach in the outer jacket and the tape layer, the corresponding localized axially and/or radially compressed portion of the C/E foam layer expands into the breach to form a corresponding localized self-healed region. The self-healing cable is manufacturable with present-day commercial self-healing cable manufacturing tools.

  18. Non-linear stochastic response of a shallow cable

    DEFF Research Database (Denmark)

    Larsen, Jesper Winther; Nielsen, Søren R.K.


    The paper considers the stochastic response of geometrical non-linear shallow cables. Large rain-wind induced cable oscillations with non-linear interactions have been observed in many large cable stayed bridges during the last decades. The response of the cable is investigated for a reduced two...

  19. Choice Of Computer Networking Cables And Their Effect On Data ...

    African Journals Online (AJOL)

    Computer networking is the order of the day in this Information and Communication Technology (ICT) age. Although a network can be through a wireless device most local connections are done using cables. There are three main computer-networking cables namely coaxial cable, unshielded twisted pair cable and the optic ...

  20. 46 CFR 111.60-4 - Minimum cable conductor size. (United States)


    ... 46 Shipping 4 2010-10-01 2010-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...

  1. Multiconductor Short/Open Cable Tester (United States)

    Eichenberg, Dennis


    Frequent or regular testing of multiconductor cables terminated in multipin conductors tedious, if not impossible, task. This inexpensive circuit simplifies open/short testing and is amenable to automation. In operation, pair of connectors selected to match pair of connectors installed on each of cables to be tested. As many connectors accommodated as required, and each can have as many conductors as required. Testing technique implemented with this circuit automated easily with electronic controls and computer interface. Printout provides status of each conductor in cable, indicating which, if any, of conductors has open or short circuit.

  2. Wire in the Cable-Driven System of Surgical Robot (United States)

    Wang, X. F.; Lv, N.; Mu, H. Z.; Xue, L. J.


    During the evolution of the surgical robot, cable plays an important role. It translates motion and force precisely from surgeon’s hand to the tool’s tips. In the paper, the vertical wires, the composition of cable, are mathematically modeled from a geometric point of view. The cable structure and tension are analyzed according to the characteristics of wire screw twist. The structural equations of the wires in different positions are derived for both non-bent cable and bent cable, respectively. The bending moment formula of bent cable is also obtained. This will help researchers find suitable cable and design more matched pulley.

  3. Submarine Landslides at Santa Catalina Island, California (United States)

    Legg, M. R.; Francis, R. D.


    Santa Catalina Island is an active tectonic block of volcanic and metamorphic rocks originally exposed during middle Miocene transtension along the evolving Pacific-North America transform plate boundary. Post-Miocene transpression created the existing large pop-up structure along the major strike-slip restraining bend of the Catalina fault that forms the southwest flank of the uplift. Prominent submerged marine terraces apparent in high-resolution bathymetric maps interrupt the steep submarine slopes in the upper ~400 meters subsea depths. Steep subaerial slopes of the island are covered by Quaternary landslides, especially at the sea cliffs and in the blueschist metamorphic rocks. The submarine slopes also show numerous landslides that range in area from a few hectares to more than three sq-km (300 hectares). Three or more landslides of recent origin exist between the nearshore and first submerged terrace along the north-facing shelf of the island's West End. One of these slides occurred during September 2005 when divers observed a remarkable change in the seafloor configuration after previous dives in the area. Near a sunken yacht at about 45-ft depth where the bottom had sloped gently into deeper water, a "sinkhole" had formed that dropped steeply to 100-ft or greater depths. Some bubbling sand was observed in the shallow water areas that may be related to the landslide process. High-resolution multibeam bathymetry acquired in 2008 by CSU Monterey Bay show this "fresh" slide and at least two other slides of varying age along the West End. The slides are each roughly 2 hectares in area and their debris aprons are spread across the first terrace at about 85-m water depth that is likely associated with the Last Glacial Maximum sealevel lowstand. Larger submarine slides exist along the steep Catalina and Catalina Ridge escarpments along the southwest flank of the island platform. A prominent slide block, exceeding 3 sq-km in area, appears to have slipped more than

  4. ROV Tiburon Investigation of Hawaiian Submarine Canyons (United States)

    Paull, C. K.; Greene, H. G.; Caress, D. W.; Clague, D. A.; Ussler, W.; Maher, N. M.


    MBARI conducted ROV dives around the Hawaiian Islands during an expedition of the R/V Western Flyer and Tiburon in the spring of 2001. Eight ROV dives were made to investigate five major submarine canyons offshore of Oahu, Molokai, and Hawaii in up to 3,434 m water depths. Four of these canyons are located off the windward (northern) side of these islands where onshore canyons are also well developed. Those canyons located offshore of Molokai and Oahu incise the head scars of the giant Nuuanu and Wailai submarine landslides. ROV observations and sediment and rock outcrop sampling were made in these canyons to determine their origin and present-day activity. The fifth canyon investigated is located on the leeward (southern) side of Molokai. The canyons along the windward side expose extensive stratigraphic sections that reveal the history of the islands' formation. In composite, these sections contain marine pillow basalt overlain by a substantial sequence of alternating subaerial lava flows, rounded boulder conglomerates, shallow water carbonates, and hyaloclastites that indicate coastal and marine deposition. These sequences illustrate the accretion and subsequent subsidence of the islands' flanks. These canyons also have morphologically distinct upper and lower sections. The upper reaches of the canyons are incised into the shallow water marine facies and contain broad axial channels through which active sediment transport is occurring. In contrast, the morphology of the lower canyons are strongly influenced by the giant landslides that massively altered the northern flanks of the Hawaiian chain. The lower canyons contain plunge pools and steep headwall scarps that are generally comprised of mechanically competent subaerial lava flows. The presence of multiple plunge pools with differentially eroded head scarps suggests retrogressive erosion (bottom-up process) with headward advancement of the various heads. Undercutting of the headwalls also produce periodic

  5. Relationship between work stress and health in submariners

    Directory of Open Access Journals (Sweden)

    Nan-nan JIANG


    Full Text Available Objective To explore the relationship between work stress and health in submariners. Methods In April 2008, 272 submariners trained in a navy base were selected as study subjects by random group sampling method, and tested by primary personal information questionnaire, self-rated health measurement scale (SRHMS, self-developed submariners' work stressors questionnaire, and work stress self-rated scale. Physical health, mental health and social health of submariners were analyzed, and scores were compared with the norm of reference scores. Correlations were analyzed respectively between 10 items of submariners' general information (including age, length of military service, education degree, years at the present post, times of receiving awards, on-duty hours, off-duty hours, hours of sleep, lost days of leave, positive attitude to work and their physical health score, mental health score, social health score, total health score, as well as between 15 submariners' work stressors (including workrelated risks, diet problems, high temperature, humidity and noise in workplace, shortage of clean clothes, illness, losing contact with outside, lack of information about the task, lacking supports from family members, relationship problems, lack of involvement in task decisions, boring and dull work, on duty, heavy work, high quality of work, coping with unexpected threat and their physical health score, mental health score, social health score and total health score. Results No significant difference was found between submariners' SRHMS total score and the normal referenced score (t=0.56, P>0.05, but the physical health score and mental health score were significantly lower than normal referenced scores respectively (t=–2.172, P<0.05; t=–3.299, P<0.01, and the social health score was significantly higher than normal referenced score (t=9.331, P<0.001. The age, length of military service, years at present post of submariners were related

  6. What Is Data Cabling and Why It's Necessary for Businesses


    IT Support


    What is Data Cabling? A structured cabling system is a type of network construction that is open and is used by different systems like data, access management, telephony, building automation, along with many other similar capabilities. It is an extremely flexible and economical set up. Usually, a cabling system such as this can be broken into six components: work space, horizontal cabling, backbone cabling, gear space, telecommunication closet (room) and entrance ways. Common Network ...

  7. MIMO Device Performance Testing with the Wireless Cable Method

    DEFF Research Database (Denmark)

    Fan, Wei; Kyösti, Pekka; Hentilä, Lassi


    Conducted cable testing has been dominantly utilized in the industry to evaluate multiple-input multiple-output (MIMO) capable mobile terminals. Desired testing signals can be guided directly to the antenna ports on the mobile terminal by radio frequency (RF) coaxial cables in the conducted cable...... of the wireless cable method is done both in simulation and active throughput measurements. Future directions and applicability of the wireless cable method are also discussed....

  8. Parametrically excited oscillation of stay cable and its control in cable-stayed bridges. (United States)

    Sun, Bing-nan; Wang, Zhi-gang; Ko, J M; Ni, Y Q


    This paper presents a nonlinear dynamic model for simulation and analysis of a kind of parametrically excited vibration of stay cable caused by support motion in cable-stayed bridges. The sag, inclination angle of the stay cable are considered in the model, based on which, the oscillation mechanism and dynamic response characteristics of this kind of vibration are analyzed through numerical calculation. It is noted that parametrically excited oscillation of a stay cable with certain sag, inclination angle and initial static tension force may occur in cable-stayed bridges due to deck vibration under the condition that the natural frequency of a cable approaches to about half of the first model frequency of the bridge deck system. A new vibration control system installed on the cable anchorage is proposed as a possible damping system to suppress the cable parametric oscillation. The numerical calculation results showed that with the use of this damping system, the cable oscillation due to the vibration of the deck and/or towers will be considerably reduced.

  9. On the Minimum Cable Tensions for the Cable-Based Parallel Robots

    Directory of Open Access Journals (Sweden)

    Peng Liu


    Full Text Available This paper investigates the minimum cable tension distributions in the workspace for cable-based parallel robots to find out more information on the stability. First, the kinematic model of a cable-based parallel robot is derived based on the wrench matrix. Then, a noniterative polynomial-based optimization algorithm with the proper optimal objective function is presented based on the convex optimization theory, in which the minimum cable tension at any pose is determined. Additionally, three performance indices are proposed to show the distributions of the minimum cable tensions in a specified region of the workspace. An important thing is that the three performance indices can be used to evaluate the stability of the cable-based parallel robots. Furthermore, a new workspace, the Specified Minimum Cable Tension Workspace (SMCTW, is introduced, within which all the minimum tensions exceed a specified value, therefore meeting the specified stability requirement. Finally, a camera robot parallel driven by four cables for aerial panoramic photographing is selected to illustrate the distributions of the minimum cable tensions in the workspace and the relationship between the three performance indices and the stability.

  10. Calibration and use of continuous heat-type automated seepage meters for submarine groundwater discharge measurements (United States)

    Mwashote, B.M.; Burnett, W.C.; Chanton, J.; Santos, I.R.; Dimova, N.; Swarzenski, P.W.


    Submarine groundwater discharge (SGD) assessments were conducted both in the laboratory and at a field site in the northeastern Gulf of Mexico, using a continuous heat-type automated seepage meter (seepmeter). The functioning of the seepmeter is based on measurements of a temperature gradient in the water between downstream and upstream positions in its flow pipe. The device has the potential of providing long-term, high-resolution measurements of SGD. Using a simple inexpensive laboratory set-up, we have shown that connecting an extension cable to the seepmeter has a negligible effect on its measuring capability. Similarly, the observed influence of very low temperature (???3 ??C) on seepmeter measurements can be accounted for by conducting calibrations at such temperatures prior to field deployments. Compared to manual volumetric measurements, calibration experiments showed that at higher water flow rates (>28 cm day-1 or cm3 cm-2 day-1) an analog flowmeter overestimated flow rates by ???7%. This was apparently due to flow resistance, turbulence and formation of air bubbles in the seepmeter water flow tubes. Salinity had no significant effect on the performance of the seepmeter. Calibration results from fresh water and sea water showed close agreement at a 95% confidence level significance between the data sets from the two media (R2 = 0.98). Comparatively, the seepmeter SGD measurements provided data that are comparable to manually-operated seepage meters, the radon geochemical tracer approach, and an electromagnetic (EM) seepage meter. ?? 2009 Elsevier Ltd.

  11. Ecology: Electrical Cable Bacteria Save Marine Life

    DEFF Research Database (Denmark)

    Nielsen, Lars Peter


    Animals at the bottom of the sea survive oxygen depletion surprisingly often, and a new study identifies cable bacteria in the sediment as the saviors. The bacterial electrical activity creates an iron 'carpet', trapping toxic hydrogen sulfide....

  12. Thermally induced EMF in unirradiated MI cables (United States)

    Vila, R.; Hodgson, E. R.


    Radiation and temperature induced currents and voltages in mineral insulated (MI) cables, (generally termed RIEMF and TIEMF, respectively) have recently been the object of discussion and study. The problem is due to a possible electromagnetic force (EMF) generated along the centre conductor of ITER magnetic diagnostic coils in a radiation field, and the difficulty of separating radiation and temperature effects from the required signal. Previous work has shown the importance of temperature gradient effects. To address this problem further, studies of TIEMF have been carried out on an MI cable across the ends of the centre conductor at temperatures up to 550 °C, making point-by-point measurements, as well as annealing tests. It has been confirmed that voltage maxima appear in well-localized regions of the cable, indicating that some inhomogeneity is present. No geometric variations were observed by X-ray imaging of the cable.

  13. Marine controlled-source electromagnetic sounding on submarine massive sulphides using 2.5-D simulation (United States)

    Imamura, N.; Goto, T.; Takekawa, J.; Mikada, H.


    Recently, controlled-source electromagnetic (EM) method is widely used for shallow sub-seafloor explorations. In conventional marine CSEM methods, we need to connect a survey vehicle and an EM transmitter using a long cable, and also connect the EM transmitter and towed receiver using a cable. However, in practice, we must tow cables far from seafloor because of rough topography (e.g, chimneys) around submarine massive sulphides (SMS). Therefore, it is difficult to get information about shallow sub-seafloor structure. In this paper, we propose a new controlled-source electromagnetic method using two autonomous underwater vehicles (AUVs) for the exploration of SMS. We set an EM transmitter to one AUV, and also set an EM receiver to another AUV. Using this method, it is possible to keep a low height of diving AUVs from the seafloor, so we can carry out the exploration of SMS effectively. A numerical simulation code for 2.5 dimensional (2.5-D) electromagnetic fields in the frequency domain is developed in order to estimate electromagnetic responses on possible conductivity structures. In this research, we compared the behavior of electric fields as various functions such as the distance between source and receiver, and discussed the possibility of our CSEM method to be applied for the exploration of SMS. From the simulation results, we found that it is possible to detect the electric field for about 150~200m offsets even under the contamination of noise. Among various combination of source and receivers, we also found that the anomalous amplitude rate becomes greatest, in particular around the edge of SMS, when polarizing both the source and receiver in the horizontal direction. We next considered the sensitivity of electromagnetic field to the location of SMS using two model calculations. We found that the received electric field becomes steeply weaker as setting the receiver apart from the transmitter when the source was placed near SMS. Above all numerical

  14. Bias in Cable News: Persuasion and Polarization


    Martin, Gregory J; Ali Yurukoglu


    We measure the persuasive effects of slanted news and tastes for like-minded news, exploiting cable channel positions as exogenous shifters of cable news viewership. Channel positions do not correlate with demographics that predict viewership and voting, nor with local satellite viewership. We estimate that Fox News increases Republican vote shares by 0.3 points among viewers induced into watching 2.5 additional minutes per week by variation in position. We then estimate a model of voters who...

  15. Cable system transients theory, modeling and simulation

    CERN Document Server

    Ametani, Akihiro; Nagaoka, Naoto


    A systematic and comprehensive introduction to electromagnetic transient in cable systems, written by the internationally renowned pioneer in this field Presents a systematic and comprehensive introduction to electromagnetic transient in cable systems Written by the internationally renowned pioneer in the field Thorough coverage of the state of the art on the topic, presented in a well-organized, logical style, from fundamentals and practical applications A companion website is available

  16. A Cable-Shaped Lithium Sulfur Battery. (United States)

    Fang, Xin; Weng, Wei; Ren, Jing; Peng, Huisheng


    A carbon nanostructured hybrid fiber is developed by integrating mesoporous carbon and graphene oxide into aligned carbon nanotubes. This hybrid fiber is used as a 1D cathode to fabricate a new cable-shaped lithium-sulfur battery. The fiber cathode exhibits a decent specific capacity and lifespan, which makes the cable-shaped lithium-sulfur battery rank far ahead of other fiber-shaped batteries. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. From submarine to lacustrine groundwater discharge (United States)

    Lewandowski, Jörg; Meinikmann, Karin; Pöschke, Franziska; Nützmann, Gunnar; Rosenberry, Donald O.


    Submarine groundwater discharge (SGD) and its role in marine nutrient cycling are well known since the last decade. The freshwater equivalent, lacustrine groundwater discharge (LGD), is often still disregarded, although first reports of LGD are more than 50 years old. We identify nine different reasons why groundwater has long been disregarded in both freshwater and marine environments such as invisibility of groundwater discharge, the size of the interface and its difficult accessibility. Although there are some fundamental differences in the hydrology of SGD and LGD, caused primarily by seawater recirculation that occurs only in cases of SGD, there are also a lot of similarities such as a focusing of discharge to near-shore areas. Nutrient concentrations in groundwater near the groundwater–surface water interface might be anthropogenically enriched. Due to spatial heterogeneity of aquifer characteristics and biogeochemical processes, the quantification of groundwater-borne nutrient loads is challenging. Both nitrogen and phosphorus might be mobile in near-shore aquifers and in a lot of case studies large groundwater-borne nutrient loads have been reported.

  18. Design and analysis of submarine radome (United States)

    Sandeep, C. Satya; Prasad, U. Shiva; Suresh, R.; Rathan, A.; Sravanthi, G.; Govardhan, D.


    Radomes are the electromagnetic windows that protect microwave sub-systems from the environmental effects. The major requirement of radome is its transparency to microwaves and for most of the cases mechanical properties are also equally important. Radome for underwater applications has to withstand high water pressure of the order of 45 bars. Composite materials owing to their high strength to weight ratio, high stiffness and better corrosion resistance are potential source for under water applications. The concept of 'tailoring' the material properties to suit the radome is obtained by selecting proper reinforcement, resin matrix and their compositions. The mechanical properties of composite material, evaluated by testing specimens as per ASTM standards, are utilized in designing the radome. The modulus properties calculated using classical theories of composite materials and compared with test results. ANSYS a Finite Element software package used to analyse the problem. As the cross sectional thickness of radome varies, the complexity in fabrication is overcome by adopting matched die techniques. The radome design and finite element analysis validation concluded by conducting the pressure test on radome. On the design a modal analysis is also carried to check for the natural frequency, So that resonance does not occur if the natural frequency of the radome coincides with the excitation frequency of the submarine Clinical information system (CIS) for UNRWA is a computerized distributed application that used in clinics which follows the United Nations Relief and Works Agency (UNRWA) to manage the clinical requirements and services.

  19. Submarine landslides of the Southern California Borderland (United States)

    Lee, H.J.; Greene, H. Gary; Edwards, B.D.; Fisher, M.A.; Normark, W.R.


    Conventional bathymetry, sidescan-sonar and seismic-reflection data, and recent, multibeam surveys of large parts of the Southern California Borderland disclose the presence of numerous submarine landslides. Most of these features are fairly small, with lateral dimensions less than ??2 km. In areas where multibeam surveys are available, only two large landslide complexes were identified on the mainland slope- Goleta slide in Santa Barbara Channel and Palos Verdes debris avalanche on the San Pedro Escarpment south of Palos Verdes Peninsula. Both of these complexes indicate repeated recurrences of catastrophic slope failure. Recurrence intervals are not well constrained but appear to be in the range of 7500 years for the Goleta slide. The most recent major activity of the Palos Verdes debris avalanche occurred roughly 7500 years ago. A small failure deposit in Santa Barbara Channel, the Gaviota mudflow, was perhaps caused by an 1812 earthquake. Most landslides in this region are probably triggered by earthquakes, although the larger failures were likely conditioned by other factors, such as oversteepening, development of shelf-edge deltas, and high fluid pressures. If a subsequent future landslide were to occur in the area of these large landslide complexes, a tsunami would probably result. Runup distances of 10 m over a 30-km-long stretch of the Santa Barbara coastline are predicted for a recurrence of the Goleta slide, and a runup of 3 m over a comparable stretch of the Los Angeles coastline is modeled for the Palos Verdes debris avalanche. ?? 2009 The Geological Society of America.

  20. Seismic reflections associated with submarine gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Andreassen, K.


    Gas hydrates are often suggested as a future energy resource. This doctoral thesis improves the understanding of the concentration and distribution of natural submarine gas hydrates. The presence of these hydrates are commonly inferred from strong bottom simulating reflection (BSR). To investigate the nature of BSR, this work uses seismic studies of hydrate-related BSRs at two different locations, one where gas hydrates are accepted to exist and interpreted to be very extensive (in the Beaufort Sea), the other with good velocity data and downhole logs available (offshore Oregon). To ascertain the presence of free gas under the BSR, prestack offset data must supplement near-vertical incidence seismic data. A tentative model for physical properties of sediments partially saturated with gas hydrate and free gas is presented. This model, together with drilling information and seismic data containing the BSR beneath the Oregon margin and the Beaufort Sea, made it possible to better understand when to apply the amplitude-versus-offset (AVO) method to constrain BSR gas hydrate and gas models. Distribution of natural gas hydrates offshore Norway and Svalbard is discussed and interpreted as reflections from the base of gas hydrate-bearing sediments, overlying sediments containing free gas. Gas hydrates inferred to exist at the Norwegian-Svalbard continental margin correlate well with Cenozoic depocenters, and the associated gas is assumed to be mainly biogenic. Parts of that margin have a high potential for natural gas hydrates of both biogenic and thermogenic origin. 235 refs., 86 figs., 4 tabs.

  1. Submarine landslides in Arctic sedimentation: Canada Basin (United States)

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Lebedova-Ivanova, N; Chapman, C.


    Canada Basin of the Arctic Ocean is the least studied ocean basin in the World. Marine seismic field programs were conducted over the past 6 years using Canadian and American icebreakers. These expeditions acquired more than 14,000 line-km of multibeam bathymetric and multi-channel seismic reflection data over abyssal plain, continental rise and slope regions of Canada Basin; areas where little or no seismic reflection data existed previously. Canada Basin is a turbidite-filled basin with flat-lying reflections correlateable over 100s of km. For the upper half of the sedimentary succession, evidence of sedimentary processes other than turbidity current deposition is rare. The Canadian Archipelago and Beaufort Sea margins host stacked mass transport deposits from which many of these turbidites appear to derive. The stratigraphic succession of the MacKenzie River fan is dominated by mass transport deposits; one such complex is in excess of 132,000 km2 in area and underlies much of the southern abyssal plain. The modern seafloor is also scarred with escarpments and mass failure deposits; evidence that submarine landsliding is an ongoing process. In its latest phase of development, Canada Basin is geomorphologically confined with stable oceanographic structure, resulting in restricted depositional/reworking processes. The sedimentary record, therefore, underscores the significance of mass-transport processes in providing sediments to oceanic abyssal plains as few other basins are able to do.

  2. Homeland Security (United States)

    Provides an overview of EPA's homeland security roles and responsibilities, and links to specific homeland security issues: water security, research, emergency response, recovery, and waste management.

  3. Two-way cable television system characterization (United States)

    Schauer, Paul T.


    This presentation is a report of the testing activities of the CableLabs Network Integrity Working Group. The working group consisted of several CableLabs member companies which conducted rf analog and digital bit-error testing at five CATV networks in the U.S. and Canada. The purpose of the working group was to measure the reliability and availability of the contemporary CATV network as specified by traditional switched access telephony performance parameters. Transmission data was collected for both forward and reverse (sub- split) paths of the rf broadband network, in both traditional and hybrid fiber/coax architectures, and for baseline and controlled variation events. The basic premise of this testing was to ascertain which cable television network elements adversely affected transmission of a 'generic' digital communications system and how they can be managed or controlled. The digital transmission utilized in the test was a QPSK modulated, T-1 rate (1.544 Mbit/second), modem without error correction. The intent was not to derive the necessary modulation technique and error correction scheme to properly operate in every cable television system, but rather to determine the principal sources of impairments existing in these networks and deduce corrective measures. The full report of the Network Integrity Working Group is published by CableLabs, Inc., and is titled, 'Two-Way Cable Television System Characterization -- Final Report', April 1995.

  4. Statistical relationships between local sea level and weather with Florida-Bahamas cable and Pegasus measurements of Florida Current volume transport (United States)

    Maul, George A.; Mayer, Dennis A.; Bushnell, Mark


    Straits of Florida sea level is studied as a measure of Florida Current volume transport because sea level provides an independent time series both (1) for detecting changes in the calibration of the Florida-Bahamas submarine cable which has been operating since 1982, and (2) as a measure of the strength of the Gulf Stream System dating to the 1930s when cable measurements were not available. Accordingly, tide gauge records from Haulover Beach (Miami) and Lake Worth, Florida, and from Cat Cay and Settlement Point, The Bahamas, together with Miami weather and cable voltage, are correlated with each other and with discrete volume transport estimated from all Pegasus data taken during the intensive 1982-1984 Subtropical Atlantic Climate Studies (STACS) observations. Time domain linear correlation coefficients between these 132 Pegasus values and cable voltage observations, Cat Cay minus Haulover Beach sea level, and Haulover Beach sea level only, are 0.91, 0.55, and -0.76, respectively, but for the 1982-1988 time series, Cat Cay minus Haulover Beach is better correlated with cable observations (0.62) than is Haulover Beach alone (-0.44). Frequency domain modeling computations reveal that the sea level and cable data are organized in such a way that most of their energy lies below frequencies of 30-1 cycles per day (cpd). In a subseasonal band (up to and including the semiannual frequency) 49% of the cable energy and 59% of the Haulover Beach energy can be accounted for using 30-day low-passed data. A subseasonal frequency response function has been tentatively identified that relates both Florida sea level and Bahamas-Florida sea level difference to cable observations and can successfully account for more than 60% of the observed cable variance (standard error is ±1×106 m3 s-1). Further, negative Florida sea level only and Bahamas-Florida sea level difference have different phase relationships with cable observations; it is suggested that steric effects could be

  5. NSMRL: A Small Command with A Huge Presence for the Submarine Force

    National Research Council Canada - National Science Library

    Daniel, J. C; Lamb, Jerry


    "To protect the health and enhance the performance of our warfighters through focused submarine, diving and surface research solutions" is the mission of the Naval Submarine Medical Research Laboratory (NSMRL...

  6. Exploring the Unknown: Cabled Ocean Observatory Data and Discovery in University Education (United States)

    Pelz, M.; Scherwath, M.; Riddell, D. J.; Hoeberechts, M.; Bourdeault-Fournier, A.; Schine, J.; Sammarco, P. M. P.


    Cabled ocean observatories, which supply continuous power and Internet connectivity to subsea instruments from the coast to the deep sea, enable us to extend our reach into unexplored regions of the ocean. Sensors become our eyes and ears in this mysterious world, allowing instructors and students to have a virtual presence in an environment that is otherwise inaccessible for human study. Networks of always-on sensors in habitats as diverse as submarine canyons, hypoxic marine basins, and active hydrothermal vent systems provide unprecedented opportunities for students to ask real scientific questions and to answer those questions with real data. Ocean Networks Canada (ONC), an initiative of the University of Victoria, operates coastal and deep ocean cabled observatories, including VENUS and NEPTUNE off the west coast of British Columbia, Canada. ONC supports instructors in the creation of lab and course materials using observatory data. Data from the observatories are freely accessible through a web-based interface, which allows students to continue their investigations beyond the in-class activities. Here, we present three examples of the application of data from Ocean Networks Canada's cabled observatories in post-secondary education: an undergraduate lab in marine ecology in which students investigate the factors affecting spatial variation in benthic animal diversity using ocean sensor data and video footage from cameras on the seafloor; an undergraduate field course in acoustic ethnography in which students incorporate recordings from ONC's hydrophone arrays; and a graduate student "research derby" in which students propose hypotheses that can be investigated using ONC data in whole or in part, with rewards for those successful in publishing the results of their study in a peer-reviewed journal within two years.

  7. Conduct and Support of Amphibious Operations from United States Submarines in World War II (United States)


    twelfth war patrol of the Gato class submarine (See photos 1 and 2). They made history as the only Americans to conduct an offensive landing on a...Naval History Vol. 2, no. 1 (April 1, 2003), 1. 4 This monograph features five Gato class submarines, and three V-class submarines, but also addresses...1993), 67. 6 Photo 2: USS Barb (SS 220), representing the five Gato class submarines that participated in Operation Torch. Barb’s crew also

  8. Index of Submarine Medical Officer’s Qualification Theses 1944-1974 (United States)



  9. Security Dilemma

    DEFF Research Database (Denmark)

    Wivel, Anders


    What is a security dilemma? What are the consequences of security dilemmas in international politics?......What is a security dilemma? What are the consequences of security dilemmas in international politics?...

  10. Study of an YBCO HTS transmission cable system

    Energy Technology Data Exchange (ETDEWEB)

    Mukoyama, S. [Furukawa Electric Co., Ltd., Ecology and Energy Laboratory, 6, Yawata-Kaigandori, Ichihara, Chiba 290-8555 (Japan)], E-mail:; Yagi, M.; Hirano, N. [Furukawa Electric Co., Ltd., Ecology and Energy Laboratory, 6, Yawata-Kaigandori, Ichihara, Chiba 290-8555 (Japan); Amemiya, N. [Yokohama National University, Yokohama 240-8501 (Japan); Kashima, N.; Nagaya, S. [Chubu Electric Power Company, Nagoya 459-8522 (Japan); Izumi, T.; Shiohara, Y. [Superconductivity Research Laboratory, Tokyo 135-0062 (Japan)


    HTS transmission cables offer an innovative transmission line that differs from conventional technologies because HTS cables can send bulk power with extremely low loss. The HTS cable will contribute to energy saving and the prevention of global warming technologically. Reduction of cable loss is the most important development in economical cables for power networks. Today, second generation (2G) wires, such as an YBCO tape, are considered to have the potential to reduce AC loss. We developed YBCO power cables and succeeded in reducing AC loss to one-sixth the loss of BSCCO cable. According to our estimations, the total loss of an YBCO cable will be half the conventional (normal conducting) cable but yield the same power capacity.

  11. Application study on the first cable-stayed bridge with CFRP cables in China

    Directory of Open Access Journals (Sweden)

    Kuihua Mei


    Full Text Available In order to push forward the development of CFRP cable-stayed bridge and accumulate experiences, the study on the application of the first cable-stayed bridge with CFRP cables in China was carried out. The design essentials of main components of the bridge were introduced and its integral performances, including static properties, dynamic properties and seismic response were analyzed using finite element method. A new bond-type anchorage was developed and the processes of fabricating and installing CFRP cables were elaborated. Based on the results of construction simulation, a tension scheme for bridge was propound. During constructing, the stresses and displacement of girder and pylon, as well as the forces and stresses of cables, were tested. The results indicate that all sections of the bridge could meet the requirements of the ultimate bearing capacity and normal service; the performance of the anchorage is good and the stresses in each cable system are similar; the tested values accord well with the calculated values. Further, creep deformation of the resin in anchorages under service load is not obvious. All these results demonstrate that the first application of CFRP cables in the cable-stayed bridge in China is successful.

  12. Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine Program: Background and Issues for Congress (United States)


    Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine Program: Background and Issues for Congress Ronald O’Rourke Specialist in Naval...Affairs April 5, 2016 Congressional Research Service 7-5700 R41129 Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine...Replacement (SSBN[X]) Ballistic Missile Submarine Program Congressional Research Service Contents Introduction

  13. Submarine fans: A critical retrospective (1950–2015

    Directory of Open Access Journals (Sweden)

    G. Shanmugam


    Full Text Available When we look back the contributions on submarine fans during the past 65 years (1950–2015, the empirical data on 21 modern submarine fans and 10 ancient deep-water systems, published by the results of the First COMFAN (Committee on FANs Meeting (Bouma et al., 1985a, have remained the single most significant compilation of data on submarine fans. The 1970s were the “heyday” of submarine fan models. In the 21st century, the general focus has shifted from submarine fans to submarine mass movements, internal waves and tides, and contourites. The purpose of this review is to illustrate the complexity of issues surrounding the origin and classification of submarine fans. The principal elements of submarine fans, composed of canyons, channels, and lobes, are discussed using nine modern case studies from the Mediterranean Sea, the Equatorial Atlantic, the Gulf of Mexico, the North Pacific, the NE Indian Ocean (Bay of Bengal, and the East Sea (Korea. The Annot Sandstone (Eocene–Oligocene, exposed at Peira-Cava area, SE France, which served as the type locality for the “Bouma Sequence”, was reexamined. The field details are documented in questioning the validity of the model, which was the basis for the turbidite-fan link. The 29 fan-related models that are of conceptual significance, developed during the period 1970–2015, are discussed using modern and ancient systems. They are: (1 the classic submarine fan model with attached lobes, (2 the detached-lobe model, (3 the channel-levee complex without lobes, (4 the delta-fed ramp model, (5 the gully-lobe model, (6 the suprafan lobe model, (7 the depositional lobe model, (8 the fan lobe model, (9 the ponded lobe model, (10 the nine models based on grain size and sediment source, (11 the four fan models based on tectonic settings, (12 the Jackfork debrite model, (13 the basin-floor fan model, (14 supercritical and subcritical fans, and (15 the three types of fan reservoirs. Each model is unique

  14. Process sedimentology of submarine fan deposits - new perspectives (United States)

    Postma, George


    To link submarine fan process sedimentology with sand distribution, sand body architecture, texture and fabric, the field geologist studies sedimentary facies, facies associations (fan elements) and stratigraphy. Facies analysis resides on factual knowledge of modern fan morphodynamics and physical modelling of en-masse sediment transport. Where do we stand after 55 years of submarine research, i.e. the date when the first submarine fan model was launched by Arnold Bouma in 1962? Since that date students of submarine fans have worked on a number of important, recurring questions concerned with facies analysis of submarine successions in outcrop and core: 1. What type of sediment transport produced the beds? 2. What facies can be related to initial flow conditions? 3. What is the significance of grain size jumps and bounding surface hierarchy in beds consisting of crude and spaced stratification (traction carpets)? Do these point to multi flow events or to flow pulsations by one and the same event? 4. What facies associations relate to the basic elements of submarine fans? 5. What are the autogenic and allogenic signatures in submarine fans? Particularly in the last decade, the enormous technical advancement helped to obtain high-quality data from observations of density flows in modern canyons, deep basins and deep-water delta slopes (refs 1,2,3). In combination with both physical (refs 4,5) and numerical modelling (ref 6) these studies broke new ground into our understanding of density flow processes in various submarine environments and have led to new concepts of submarine fan building by super- and subcritical high-density flow (ref 7). Do these new concepts provide better answers to our recurrent questions related to the morphodynamics of submarine fans and prediction of sand body architecture? In discussing this open question, I shall 1. apply the new concepts to a modern and ancient example of a channel-lobe-transition-zone (ref 8); 2. raise the problem of

  15. Applying Diagnostics to Enhance Cable System Reliability (Cable Diagnostic Focused Initiative, Phase II)

    Energy Technology Data Exchange (ETDEWEB)

    Hartlein, Rick [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Hampton, Nigel [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Perkel, Josh [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Hernandez, JC [Univ. de Los Andes, Merida (Venezuela); Elledge, Stacy [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); del Valle, Yamille [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Grimaldo, Jose [Georgia Inst. of Technology, Atlanta, GA (United States). School of Electrical and Computer Engineering; Deku, Kodzo [Georgia Inst. of Technology, Atlanta, GA (United States). George W. Woodruff School of Mechanical Engineering


    The Cable Diagnostic Focused Initiative (CDFI) played a significant and powerful role in clarifying the concerns and understanding the benefits of performing diagnostic tests on underground power cable systems. This project focused on the medium and high voltage cable systems used in utility transmission and distribution (T&D) systems. While many of the analysis techniques and interpretations are applicable to diagnostics and cable systems outside of T&D, areas such as generating stations (nuclear, coal, wind, etc.) and other industrial environments were not the focus. Many large utilities in North America now deploy diagnostics or have changed their diagnostic testing approach as a result of this project. Previous to the CDFI, different diagnostic technology providers individually promoted their approach as the “the best” or “the only” means of detecting cable system defects.

  16. Evaluation of cable ageing in Nuclear Power Plants; Evaluacion del envejecimiento de cables en centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Vergara, T. [Empresarios Agrupados, A. I. E. Madrid (Spain); Alonso Chicote, J. [TECNATOM, S. A. (Spain); Burnay, S. [AEA Technology (UK)


    The majority of power, control and instrumentation cables in nuclear power plants use polymers as their basic material for insulation and jacket. In many cases, these cables form part of safety-related circuits and should therefore be capable of operating correctly under both normal and accident conditions. Since polymeric materials are degraded by the long term action of the radiation and thermal environments found in the plant, it is important to be able to establish the cable condition during the plant lifetime. Nowadays there are a number of different methods to evaluate the remaining lifetime of cables. In the case of new plants, or new cables in old plants, accelerated ageing tests and predictive models can be used to establish the behaviour of the cable materials under operating conditions. There are verified techniques and considerable experience in the definition of predictive models. This type of approach is best carried out during the commissioning stage or in the early stages of operation. In older plants, particularly where there is a wide range of cable types in use, it is more appropriate to use condition monitoring methods to establish the state of degradation of cables in-plant. Over the last 10 years there have been considerable developments in methods for condition monitoring of cables and a tool-box of practical techniques are now available. There is no single technique which is suitable for all cable materials but the range of methods covers nearly all of the types currently in use, at present, the most established methods are the indented, thermal analysis (OIT, OITP and TGA) and dielectric loss measurements, All of these are either non-destructive methods or require only micro-samples of material. (Author) 15 refs.

  17. Detonator cable initiation system safety investigation: Consequences of energizing the detonator and actuator cables

    Energy Technology Data Exchange (ETDEWEB)

    Osher, J.; Chau, H.; Von Holle, W.


    This study was performed to explore and assess the worst-case response of a W89-type weapons system, damaged so as to expose detonator and/or detonator safing strong link (DSSL) cables to the most extreme, credible lightning-discharge, environment. The test program used extremely high-current-level, fast-rise-time (1- to 2-{mu}s) discharges to simulate lightning strikes to either the exposed detonator or DSSL cables. Discharges with peak currents above 700 kA were required to explode test sections of detonator cable and launch a flyer fast enough potentially to detonate weapon high explosive (HE). Detonator-safing-strong-link (DSSL) cables were exploded in direct contact with hot LX-17 and Ultrafine TATB (UFTATB). At maximum charging voltage, the discharge system associated with the HE firing chamber exploded the cables at more than 600-kA peak current; however, neither LX-17 nor UFTATB detonated at 250{degree}C. Tests showed that intense surface arc discharges of more than 700 kA/cm in width across the surface of hot UFTATB [generally the more sensitive of the two insensitive high explosives (IHE)] could not initiate this hot IHE. As an extension to this study, we applied the same technique to test sections of the much-narrower but thicker-cover-layer W87 detonator cable. These tests were performed at the same initial stored electrical energy as that used for the W89 study. Because of the narrower cable conductor in the W87 cables, discharges greater than 550-kA peak current were sufficient to explode the cable and launch a fast flyer. In summary, we found that lightning strikes to exposed DSSL cables cannot directly detonate LX-17 or UFTATB even at high temperatures, and they pose no HE safety threat.

  18. High voltage pulsed cable design: a practical example

    Energy Technology Data Exchange (ETDEWEB)

    Kewish, R.W. Jr.; Boicourt, G.P.


    The design of optimum high voltage pulse cable is difficult because very little emperical data are available on performance in pulsed applications. This paper follows the design and testing of one high voltage pulse cable, 40/100 trigger cable. The design was based on an unproven theory and the impressive outcome lends support to the theory. The theory is outlined and it is shown that there exists an inductance which gives a cable of minimum size for a given maximum stress. Test results on cable manufactured according to the design are presented and compared with the test results on the cable that 40/100 replaces.

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

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Okholm, Jan; Lomholt, Karin


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

  20. Stability Measurements of Rutherford Cables with Various Treatments

    CERN Document Server

    Kim, S W; Wilson, M N; Ghosh, A; Sampson, W B


    To improve the stability of Rutherford type superconducting cables, various methods of treating cables were considered and tested. These treatments include strand coating, partial soldering, "barber-pole" insulation and "porous $9 metal" solder filling. To study the effect of these treatments, several cables were prepared and MQE (minimum quench energy) values were measured. Coating, partial soldering or "barber-pole insulation" improved the relative stability $9 for some cables. The "porous metal" filled cables showed higher MQE. However the results suggest that the porous metal process needs to be improved. The measured data for cables with various treatments are presented. (8 refs).

  1. Development of innovative superconducting DC power cable

    Energy Technology Data Exchange (ETDEWEB)

    Matsushita, Teruo; Kiuchi, Masaru [Dept. of Computer Science and Electronics Kyushu Institute of Technology, Iizuka (Japan)


    It is required to reduce the cost of superconducting cable to realize a superconducting DC power network that covers a wide area in order to utilize renewable energy. In this paper a new concept of innovative cable is introduced that can enhance the current-carrying capacity even though the same superconducting tape is used. Such a cable can be realized by designing an optimal winding structure in such a way that the angle between the tape and magnetic field becomes small. This idea was confirmed by preliminary experiments for a single layer model cable made of Bi-2223 tapes and REBCO coated conductors. Experiments of three and four layer cables of practical sizes were also done and it was found that the current-carrying capacity increased as theoretically predicted. If the critical current properties of commercial superconducting tapes are further improved in a parallel magnetic field, the enhancement will become pronounced and this technology will surely contribute to realization of superconducting DC power network.

  2. Coaxial cable distribution plant performance simulation (United States)

    Carangi, Mark D.; Chen, Walter Y.; Kerpez, Kenneth J.; Valenti, Craig F.


    The CATV system delivers analog video signals from a centralized headend through a tree- and-branch fiber/coax network. That architecture is very cost effective for delivering broadcast video channels to a vast area. The introduction of interactive TV, data and telephony services requires an upstream link from customers to the headend. Although equipment for upstream transmission is available, CATV systems are primarily engineered for the delivery of one way analog broadcast TV programs. In this paper, issues related to two-way digital transmission through the coaxial cable distribution plant are examined. The objective is to establish a reliable computer modeling environment for the study and simulation of general and advanced transmission systems over the coaxial cable distribution plant. The discussions are focused on three general topics: the coaxial cable distribution plant transmission channel, the corresponding noise environment, and applicable transmission system architectures. Two- port network models are developed for the components (coaxial cable, taps, etc.) of the coaxial cable distribution plant. A realistic distribution plant channel model can be constructed based on these component models. The distribution plant noise level is analyzed based on thermal noise level, amplifier noise figure, and the funneling effect. The upstream ingress noise model is also developed. Three advanced transmission systems, adaptive transmitter, frame based equalization, and discrete multitone (DMT), are presented. End to end computer simulation results are presented using QPSK upstream.

  3. The glass story: fibre optic cable

    Energy Technology Data Exchange (ETDEWEB)



    Fibre optic cable has become the glamour pinup among cables as a result of its ability to carry billions of digital bits of information per second. Fibre optic cables consist of hair-thin fibres of high purity silica glass; enclosed in its protective shield and glass cladding, the cable is immune to electromagnetic interference and carries out its task without the need for boosting. It is the perfect answer to the ever-increasing need for speed and capacity of today's high-speed computers. This paper describes the nature of fibre optics, the two major optical fibre categories of multi-mode and single-mode, and the various possible applications for each type. Although the optical performance of fibres is relatively standardized regardless of the manufacturer, physical characteristics do vary across the industry. Fibre type and fibre parameters are usually defined by the transmission system application, whereas the cable design is usually determined by the physical environment of the particular installation. 1 tab., 5 figs.

  4. Electrothermal Coordination in Cable Based Transmission Grids

    DEFF Research Database (Denmark)

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


    behavior of the components. The dynamic temperature calculations of power cables are suggested to be based on thermoelectric equivalents (TEEs). It is shown that the thermal behavior can be built into widely used load flow software, creating a strong ETC tool. ETC is, through two case scenarios, proven......Electrothermal coordination (ETC) is introduced for cable based transmission grids. ETC is the term covering operation and planning of transmission systems based on temperature, instead of current. ETC consists of one part covering the load conditions of the system and one covering the thermal...... to be beneficial for both operator and system planner. It is shown how the thermal behavior can be monitored in real-time during normal dynamic load and during emergencies. In that way, ETC enables cables to be loaded above their normal rating, while maintaining high reliability of the system, which potentially...

  5. Computer-Aided Engineering Of Cabling (United States)

    Billitti, Joseph W.


    Program generates data sheets, drawings, and other information on electrical connections. DFACS program, centered around single data base, has built-in menus providing easy input of, and access to, data for all personnel involved in system, subsystem, and cabling. Enables parallel design of circuit-data sheets and drawings of harnesses. Also recombines raw information to generate automatically various project documents and drawings, including index of circuit-data sheets, list of electrical-interface circuits, lists of assemblies and equipment, cabling trees, and drawings of cabling electrical interfaces and harnesses. Purpose of program to provide engineering community with centralized data base for putting in, and gaining access to, functional definition of system as specified in terms of details of pin connections of end circuits of subsystems and instruments and data on harnessing. Primary objective to provide instantaneous single point of interchange of information, thus avoiding

  6. Distance and Cable Length Measurement System (United States)

    Hernández, Sergio Elias; Acosta, Leopoldo; Toledo, Jonay


    A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement. PMID:22303169

  7. Distance and Cable Length Measurement System

    Directory of Open Access Journals (Sweden)

    Jonay Toledo


    Full Text Available A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement.

  8. Analysis of Electrical Coupling Parameters in Superconducting Cables

    CERN Document Server

    Bottura, L; Rosso, C


    The analysis of current distribution and redistribution in superconducting cables requires the knowledge of the electric coupling among strands, and in particular the interstrand resistance and inductance values. In practice both parameters can have wide variations in cables commonly used such as Rutherford cables for accelerators or Cable-in-Conduits for fusion and SMES magnets. In this paper we describe a model of a multi-stage twisted cable with arbitrary geometry that can be used to study the range of interstrand resistances and inductances that is associated with variations of geometry. These variations can be due to cabling or compaction effects. To describe the variations from the nominal geometry we have adopted a cable model that resembles to the physical process of cabling and compaction. The inductance calculation part of the model is validated by comparison to semi-analytical results, showing excellent accuracy and execution speed.

  9. Energy analysis of vehicle-to-cable barrier impacts. (United States)


    An accident reconstruction technique was developed for estimating the energy absorbed during an impact with a cable barrier system as well as the initial impact velocity. The kinetic energy absorbed during a cable barrier system impact is comprised o...

  10. Superconducting power cables in Denmark - a case study

    DEFF Research Database (Denmark)

    Østergaard, Jacob


    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......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...... considers the design and development of a calculation model for an HTS cable system including auxiliary facilities. From calculations of the selected transmission line, conclusions on the feasibility of HTS cables in Denmark are made. HTS cables appear to be feasible in Denmark. Calculations indicate...

  11. Modeling of the power cable production line

    Energy Technology Data Exchange (ETDEWEB)

    Kosar, Vanja; Gomzi, Zoran [Faculty of Chemical Engineering and Technology, Department of Reaction Engineering and Catalysis, University of Zagreb, Savska c. 16, HR-10000 Zagreb (Croatia)


    During the manufacturing of a power cable insulated with the cross-linkable polyethylene, the hot polymer is applied to the conductor by extrusion, below temperatures of the rapid cross-linking. The coated cable passes into a high-pressure tube (filled with nitrogen under the pressure of 10 bar) in order to heat up the insulation to temperatures at which the cross-linking agent is highly active. This is the continuous vulcanization (CV) tube. Changes of process variables associated with the CV tube can cause changes in the physical properties, the aging characteristics, and especially the heat resistance of the cable insulation. Performance of insulating compounds in this area of the cross-linking process can determine maximum output rates of a power cable manufacturing facility. The mathematical model describes cross-linking process in the vulcanization tube, which is in fact a tubular reactor. In the vulcanization tube heat is transferred by convection, conduction and radiation. Also, the reaction heat is liberated by the chemical reaction and the heat balance describes all four impacts. Formal part of the mathematical model is a material balance that describes the reactions kinetics. Heat and mole balance are connected with reaction rate and mathematically present a system of partial differential equations which will be numerically solved for chosen boundary conditions, both for the reaction part and for the cooling part of a process. On the basis of the real process parameters and the presented mathematical model simulation of the process was conducted. From the presented simulation the optimal process parameters such as process temperatures, cable linear velocity (u) and cable cooling properties of CV line are predicted and evaluated. (author)

  12. Ecuador: David y Goliat en el cable

    Directory of Open Access Journals (Sweden)

    Blasco Fernando Checa Montúfar


    Full Text Available Hay un enorme desequilibrio en la televisión ecuatoriana pagada, por un lado la existencia solo de dos operadores de cable, uno de los cuales capta el 90 por ciento del mercado actual y por otro, la histórica supremacía de Estados Unidos en la pantalla electrónica latinoamericana es más dramática en el cable ecuatoriano: en algún caso, el 80 por ciento de canales ofertados provienen de ese país. Es necesaria una "honda" sostenida, compartida y plural para derribar esta supremacía.

  13. Calorimetric measurements of losses in HTS cables

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Veje, Niels Erling Winsløv; Rasmussen, Carsten


    A calorimetric test rig is used to investigate various loss components in a 10 m long superconducting cable model. A calorimetric technique, based on thermocouple measurements, is used to measure the losses of the 10 m long superconducting cable model. The current dependent losses are also measured...... electrically and compared with the losses obtained with the calorimetric method. The results obtained by the two methods are consistent. Based on an I2 (current) fitting procedure, the loss, caused by the eddy current generated in the stainless steel cryostat housing, and the hysteresis loss generated...

  14. Power applications for superconducting cables in Denmark

    DEFF Research Database (Denmark)

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


    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...... 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...

  15. Influence of Icing on Bridge Cable Aerodynamics

    DEFF Research Database (Denmark)

    Koss, Holger; Frej Henningsen, Jesper; Olsen, Idar


    °C may lead to large amplitude vibrations of bridge cables under wind action. For the prediction of aerodynamic instability quasi-steady models have been developed estimating the cable response magnitude based on structural properties and aerodynamic force coefficients for drag, lift and torsion....... The determination of these force coefficients require a proper simulation of the ice layer occurring under the specific climatic conditions, favouring real ice accretion over simplified artificial reproduction. The work presented in this paper was performed to study the influence of ice accretion on the aerodynamic...

  16. A submarine volcanic eruption leads to a novel microbial habitat. (United States)

    Danovaro, Roberto; Canals, Miquel; Tangherlini, Michael; Dell'Anno, Antonio; Gambi, Cristina; Lastras, Galderic; Amblas, David; Sanchez-Vidal, Anna; Frigola, Jaime; Calafat, Antoni M; Pedrosa-Pàmies, Rut; Rivera, Jesus; Rayo, Xavier; Corinaldesi, Cinzia


    Submarine volcanic eruptions are major catastrophic events that allow investigation of the colonization mechanisms of newly formed seabed. We explored the seafloor after the eruption of the Tagoro submarine volcano off El Hierro Island, Canary Archipelago. Near the summit of the volcanic cone, at about 130 m depth, we found massive mats of long, white filaments that we named Venus's hair. Microscopic and molecular analyses revealed that these filaments are made of bacterial trichomes enveloped within a sheath and colonized by epibiotic bacteria. Metagenomic analyses of the filaments identified a new genus and species of the order Thiotrichales, Thiolava veneris. Venus's hair shows an unprecedented array of metabolic pathways, spanning from the exploitation of organic and inorganic carbon released by volcanic degassing to the uptake of sulfur and nitrogen compounds. This unique metabolic plasticity provides key competitive advantages for the colonization of the new habitat created by the submarine eruption. A specialized and highly diverse food web thrives on the complex three-dimensional habitat formed by these microorganisms, providing evidence that Venus's hair can drive the restart of biological systems after submarine volcanic eruptions.

  17. Does calving matter? Evidence for significant submarine melt (United States)

    Bartholomaus, Timothy C.; Larsen, Christopher F.; O’Neel, Shad


    During the summer in the northeast Pacific Ocean, the Alaska Coastal Current sweeps water with temperatures in excess of 12 °C past the mouths of glacierized fjords and bays. The extent to which these warm waters affect the mass balance of Alaskan tidewater glaciers is uncertain. Here we report hydrographic measurements made within Icy Bay, Alaska, and calculate rates of submarine melt at Yahtse Glacier, a tidewater glacier terminating in Icy Bay. We find strongly stratified water properties consistent with estuarine circulation and evidence that warm Gulf of Alaska water reaches the head of 40 km-long Icy Bay, largely unaltered. A 10–20 m layer of cold, fresh, glacially-modified water overlies warm, saline water. The saline water is observed to reach up to 10.4 °C within 1.5 km of the terminus of Yahtse Glacier. By quantifying the heat and salt deficit within the glacially-modified water, we place bounds on the rate of submarine melt. The submarine melt rate is estimated at >9 m d−1, at least half the rate at which ice flows into the terminus region, and can plausibly account for all of the submarine terminus mass loss. Our measurements suggest that summer and fall subaerial calving is a direct response to thermal undercutting of the terminus, further demonstrating the critical role of the ocean in modulating tidewater glacier dynamics.

  18. Submarine Construction in Germany (U-Bootbau in Deutschland), (United States)


    the IKL sister firm, Maschinenbau Gabler GmbH, also founded by Prof. Gabler, which, unlike IKL (involved solely in development), is a hardware...snorkels, radar masts, as well as wharf and dockside connections, for IKL and various submarine yards. Moreover, Maschinenbau Gabler is engaged in

  19. Dissolved Nutrients from Submarine Groundwater in Flic en Flac ...

    African Journals Online (AJOL)

    Abstract—The aim of this study was to investigate dissolved nutrients in a submarine groundwater discharge (SGD) in Flic en Flac lagoon on the west coast of the volcanic island of Mauritius. The SGD enters Flic en Flac lagoon through a thin blanket of unconsolidated sediment through a fracture system and is concentrated ...

  20. Dissolved Nutrients from Submarine Groundwater in Flic en Flac ...

    African Journals Online (AJOL)

    The aim of this study was to investigate dissolved nutrients in a submarine groundwater discharge (SGD) in Flic en Flac lagoon on the west coast of the volcanic island of Mauritius. The SGD enters Flic en Flac lagoon through a thin blanket of unconsolidated sediment through a fracture system and is concentrated along the ...

  1. Simulation of Wave-Plus-Current Scour beneath Submarine Pipelines

    DEFF Research Database (Denmark)

    Eltard-Larsen, Bjarke; Fuhrman, David R.; Sumer, B. Mutlu


    A fully coupled hydrodynamic and morphologic numerical model was utilized for the simulation of wave-plus-current scour beneath submarine pipelines. The model was based on incompressible Reynolds-averaged Navier–Stokes equations, coupled with k-ω turbulence closure, with additional bed and suspen...

  2. Sedimentary characteristics of samples collected from some submarine canyons

    NARCIS (Netherlands)

    Bouma, Arnold H.

    Oriented rectangular cores of 20.3 × 30.5 cm and 45.7 cm high have been collected in a number of submarine canyons off southern California (U.S.A.) and off the southern tip of Baja California (Mexico) for a detailed study of their sedimentary structures. By applying several methods, mainly X-ray

  3. 'Good Hunting': German submarine offensives and South African ...

    African Journals Online (AJOL)

    The first German submarine offensive in South African waters during 1942, Operation Eisbär, was aimed at striking a devastating blow to shipping off the South African coast. By the end of December 1942, an estimated 310 864 tons of shipping had been sunk through Operation Eisbär and the first U-cruiser operation alone.

  4. Cost Estimation Lessons Learned for Future Submarine Acquisition Programs (United States)


    North Carolina and New Mexico 30 General Dynamics Electric Boat “U.S. Navy Awards General Dynamics $14 Billion Contract for Eight Virginia- Class...NAVSEA Program Executive officer, Submarines PMO 450, June 1995. “New SSN Program Life Cycle Cost Estimate.” Naval Center for Cost Analysis: GE-1300

  5. An ongoing large submarine landslide at the Japan trench (United States)

    Nitta, S.; Kasaya, T.; Miura, S.; Kawamura, K.


    This paper deals with an active submarine landslide on a landward trench slope in the Japan trench. Studied area is located on the upper terrace ranging from 400 to 1200 m in water depth, off Sendai, northeast Japan. We have surveyed in detail the seabed topography using a multi narrow beam (hereafter MBES) and a subbottom profiler (hereafter SBP) during the cruise MR12-E02 of R/V Mirai. The survey lines were 12 lines in N-S, and 3 lines in E-W, and situated in the region from 141°45'E, 37°40'N to 142°33'E, 38°32'N. Moreover, we used multi-channel seismic profile by the cruise KR04-10 of R/V Kairei in the interpretation of the SBP results. In general, horseshoe-shaped depressions of about 100 km wide along the trench slope are arrayed along the Japan trench. It has thought that they were formed by large submarine landslides, but we could not understand critically the relationship between the depressions and the submarine landslides. Based on the survey results, we found signals of an active submarine landslide in the depression as follows. 1) We observed arcuate-shaped lineaments, which are sub-parallel to a horseshoe-shaped depression. The lineaments concentrate in the south region from 38°N at about 20 km wide. These lineaments are formed by deformation structures as anticlines, synclines and normal fault sense displacements. 2) Most of the synclines and anticlines are not buried to form the lineaments. 3) Normal faults cutting about 1 km deep are observed in a multi-channel seismic profile. The normal faults are located just below the arcuate-shaped lineaments, and are tilted eastward being the downslope direction. It indicates a large submarine landslide. We concluded that the arcuate-shaped lineaments were generated by surface sediment movement with the submarine landsliding. We think that the submarine landslide of about 20 km wide and about 1 km thick move continuously down the landward trench slope. This would be the formation process of the horseshoe

  6. 24 CFR 3285.906 - Telephone and cable TV. (United States)


    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Telephone and cable TV. 3285.906... Installation Instructions § 3285.906 Telephone and cable TV. It is recommended that the installation instructions explain that telephone and cable TV wiring should be installed in accordance with requirements of...

  7. 24 CFR 3285.704 - Telephone and cable TV. (United States)


    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Telephone and cable TV. 3285.704....704 Telephone and cable TV. Refer to § 3285.906 for considerations pertinent to installation of telephone and cable TV. ...

  8. Results from the Danish high temperature superconducting power cable project

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Østergaard, Jacob


    For the first time, a high temperature superconducting (HTS) demonstration cable system has been installed in a utility network supplying electricity to consumers. The cable is a 30-m long, 30kVrms, 2, 000Arms cable, installed in the network of Copenhagen Energy at a substation supplying...

  9. Perturbation of near-field scan from connected cables

    DEFF Research Database (Denmark)

    Sørensen, Morten; Franek, Ondrej; Pedersen, Gert Frølund


    The perturbation of near-fields scan from connected cables are investigated and how to handle the cables is discussed. A connected cable induced small but theoretical detectable changes in the near-field. This change can be seen in Huygens’ box simulations (equivalent source currents on a box) at...

  10. Cable Television 1980: Status and Prospect for Higher Education. (United States)

    Baus, F., Ed.

    Baseline information for the would-be cable television educational programer is provided by two papers, one an overview of the state of the cable television industry, and the other a report on a marketing study conducted to determine consumer attitudes toward cable TV as an educational medium. In "The Promise and Reality of Cable…

  11. Numerical solutions of the current distribution in superconducting cables

    NARCIS (Netherlands)

    Hartmann, R.A.; Rem, P.C.; van de Klundert, L.J.M.


    Superconducting cables are described by current sheets using the continuum model of W. Carr Jr. [1] and assuming an anisotropic conductivity. Two different situations are considered: a) finite length of cable in spatially independent magnetic field; b) infinitely long cable in a periodical magnetic

  12. FCC Commissioner, Legal Assistant and Staff Perceptions of Cable TV. (United States)

    Krugman, Dean M.


    Describes a methodology used in interviewing Federal Communications Commission commissioners, legal assistants, and Cable Bureau staff members about their attitudes toward the cable industry and regulation; reports results of the interviews, noting respondents' disappointment in the lack of cable growth. (GT)

  13. 47 CFR 76.111 - Cable sports blackout. (United States)


    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Cable sports blackout. 76.111 Section 76.111... CABLE TELEVISION SERVICE Network Non-duplication Protection, Syndicated Exclusivity and Sports Blackout § 76.111 Cable sports blackout. (a) No community unit located in whole or in part within the specified...

  14. 30 CFR 75.804 - Underground high-voltage cables. (United States)


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Underground high-voltage cables. 75.804 Section... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution § 75.804 Underground high-voltage cables. (a) Underground high-voltage cables used in resistance...

  15. 30 CFR 75.600-1 - Approved cables; flame resistance. (United States)


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved cables; flame resistance. 75.600-1 Section 75.600-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... cables; flame resistance. Cables shall be accepted or approved by MSHA as flame resistant. ...

  16. 30 CFR 75.600 - Trailing cables; flame resistance. (United States)


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables; flame resistance. 75.600 Section 75.600 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... cables; flame resistance. Trailing cables used in coal mines shall meet the requirements established by...

  17. Exploring the submarine Graham Bank in the Sicily Channel

    Directory of Open Access Journals (Sweden)

    Mauro Coltelli


    Full Text Available In the Sicily Channel, volcanic activity has been concentrated mainly on the Pantelleria and Linosa islands, while minor submarine volcanism took place in the Adventure, Graham and Nameless banks. The volcanic activity spanned mostly during Plio-Pleistocene, however, historical submarine eruptions occurred in 1831 on the Graham Bank and in 1891 offshore Pantelleria Island. On the Graham Bank, 25 miles SW of Sciacca, the 1831 eruption formed the short-lived Ferdinandea Island that represents the only Italian volcano active in historical times currently almost completely unknown and not yet monitored. Moreover, most of the Sicily Channel seismicity is concentrated along a broad NS belt extending from the Graham Bank to Lampedusa Island. In 2012, the Istituto Nazionale di Geofisica e Vulcanologia (INGV carried out a multidisciplinary oceanographic cruise, named “Ferdinandea 2012”, the preliminary results of which represent the aim of this paper. The cruise goal was the mapping of the morpho-structural features of some submarine volcanic centres located in the northwestern side of the Sicily Channel and the temporary recording of their seismic and degassing activity. During the cruise, three OBS/Hs (ocean bottom seismometer with hydrophone were deployed near the Graham, Nerita and Terribile submarine banks. During the following 9 months they have recorded several seismo-acoustic signals produced by both tectonic and volcanic sources. A high-resolution bathymetric survey was achieved on the Graham Bank and on the surrounding submarine volcanic centres. A widespread and voluminous gas bubbles emission was observed by both multibeam sonar echoes and a ROV (remotely operated vehicle along the NW side of the Graham Bank, where gas and seafloor samples were also collected.

  18. Broadband Wireline Provider Service: Cable Modem - Other; BBRI_cableOther12 (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Cable Modem - Other" technology. Broadband availability is...

  19. Broadband Wireline Provider Service: Cable Modem - DOCSIS 3.0; BBRI_cableDOCSIS12 (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Cable Modem - DOCSIS 3.0" technology. Broadband availability is...

  20. Bulk Electrical Cable Non-Destructive Examination Methods for Nuclear Power Plant Cable Aging Management Programs

    Energy Technology Data Exchange (ETDEWEB)

    Glass, Samuel W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Anthony M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hartman, Trenton S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    This Pacific Northwest National Laboratory milestone report describes progress to date on the investigation of nondestructive test methods focusing particularly on bulk electrical test methods that provide key indicators of cable aging and damage. The work includes a review of relevant literature as well as hands-on experimental verification of inspection capabilities. As nuclear power plants consider applying for second, or subsequent, license renewal to extend their operating period from 60 years to 80 years, it is important to understand how the materials installed in plant systems and components will age during that time and develop aging management programs to assure continued safe operation under normal and design basis events (DBE). Normal component and system tests typically confirm the cables can perform their normal operational function. The focus of the cable test program, however, is directed toward the more demanding challenge of assuring the cable function under accident or DBE. The industry has adopted 50% elongation at break (EAB) relative to the un-aged cable condition as the acceptability standard. All tests are benchmarked against the cable EAB test. EAB, however, is a destructive test so the test programs must apply an array of other nondestructive examination (NDE) tests to assure or infer the overall set of cable’s system integrity. Assessment of cable integrity is further complicated in many cases by vendor’s use of dissimilar material for jacket and insulation. Frequently the jacket will degrade more rapidly than the underlying insulation. Although this can serve as an early alert to cable damage, direct test of the cable insulation without violating the protective jacket becomes problematic. This report addresses the range of bulk electrical NDE cable tests that are or could be practically implemented in a field-test situation with a particular focus on frequency domain reflectometry (FDR). The FDR test method offers numerous advantages

  1. Microminiature coaxial cable and method of manufacture (United States)

    Bongianni, Wayne L.


    A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 .mu.m thick and from 150 to 200 .mu.m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately, the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microspheres to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion.

  2. Microminiature coaxial cable and methods of manufacture (United States)

    Bongianni, W.L.


    A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 thick and from 150 to 200 wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dieleectric. Alternately the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microballoons to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion.

  3. Microminiature coaxial cable and methods manufacture (United States)

    Bongianni, Wayne L.


    A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 .mu.m thick and from 150 to 200 .mu.m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microballoons to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion.

  4. Microminiature coaxial cable and method of manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Bongianni, W.L.


    A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 [mu]m thick and from 150 to 200 [mu]m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately, the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microspheres to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion. 2 figs.

  5. Microminiature coaxial cable and methods manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Bongianni, W.L.


    A coaxial cable is provided having a ribbon inner conductor surrounded by a dielectric and a circumferential conductor. The coaxial cable may be microminiature comprising a very thin ribbon strip conductor from between 5 to 15 [mu]m thick and from 150 to 200 [mu]m wide, having a surrounding foamed dielectric or parylene applied thereon by a vapor plasma process and an outer conductor of an adhering high conductivity metal vacuum deposited on the dielectric. Alternately the foam dielectric embodiment may have a contiguous parylene coating applied adjacent the inner conductor or the outer conductor or both. Also, the cable may be fabricated by forming a thin ribbon of strip conductive material into an inner conductor, applying thereabout a dielectric by spraying on a solution of polystyrene and polyethylene and then vacuum depositing and adhering high conductivity metal about the dielectric. The cable strength may be increased by adding glass microfilament fibers or glass microballoons to the solution of polystyrene and polyethylene. Further, the outer conductive layer may be applied by electroless deposition in an aqueous solution rather than by vacuum deposition. A thin coating of parylene is preferably applied to the outer conductor to prevent its oxidation and inhibit mechanical abrasion. 2 figs.

  6. 14 CFR 25.689 - Cable systems. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cable systems. 25.689 Section 25.689 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... smaller than 1/8 inch in diameter may be used in the aileron, elevator, or rudder systems; and (2) Each...

  7. History of cable-stayed bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen


    The principle of supporting a bridge deck by inclined tension members leading to towers on either side of the span has been known for centuries. However, the real development of cable-stayed bridges did not begin before the 1950s. Since then the free span has been increased from 183 m in the Strö...

  8. Space charge fields in DC cables

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson; Crichton, George C; Pedersen, Aage


    The space charge that accumulates in DC cables can, mathematically, be resolved into two components. One is related to the temperature and the other to the magnitude of the electric field strength. Analytical expressions for the electric fields arising from each of these space charge components...

  9. Cinema Futures: Cain, Abel or Cable?

    NARCIS (Netherlands)

    Elsaesser, Thomas; Hoffmann, Kay


    In the late 1960s, the cinema was pronounced dead. Television, like a Biblical Cain had slain his brother Abel. Some thirty years later, a remarkable reversal: rarely has the cinema been more popular. And yet, rarely has the cinema's future seemed more uncertain. Cinema Futures: Cain, Abel or Cable?

  10. Power laws from linear neuronal cable theory

    DEFF Research Database (Denmark)

    Pettersen, Klas H; Lindén, Henrik Anders; Tetzlaff, Tom


    suggested to be at the root of this phenomenon, we here demonstrate a possible origin of such power laws in the biophysical properties of single neurons described by the standard cable equation. Taking advantage of the analytical tractability of the so called ball and stick neuron model, we derive general...

  11. Study on Impedance Characteristics of Aircraft Cables

    Directory of Open Access Journals (Sweden)

    Weilin Li


    Full Text Available Voltage decrease and power loss in distribution lines of aircraft electric power system are harmful to the normal operation of electrical equipment and may even threaten the safety of aircraft. This study investigates how the gap distance (the distance between aircraft cables and aircraft skin and voltage frequency (variable frequency power supply will be adopted for next generation aircraft will affect the impedance of aircraft cables. To be more precise, the forming mechanism of cable resistance and inductance is illustrated in detail and their changing trends with frequency and gap distance are analyzed with the help of electromagnetic theoretical analysis. An aircraft cable simulation model is built with Maxwell 2D and the simulation results are consistent with the conclusions drawn from the theoretical analysis. The changing trends of the four core parameters of interest are analyzed: resistance, inductance, reactance, and impedance. The research results can be used as reference for the applications in Variable Speed Variable Frequency (VSVF aircraft electric power system.

  12. Galloping instability to chaos of cables

    CERN Document Server

    Luo, Albert C J


    This book provides students and researchers with a systematic solution for fluid-induced structural vibrations, galloping instability and the chaos of cables. They will also gain a better understanding of stable and unstable periodic motions and chaos in fluid-induced structural vibrations. Further, the results presented here will help engineers effectively design and analyze fluid-induced vibrations.

  13. Security Expertise

    DEFF Research Database (Denmark)

    and to reflect on the impact and responsibility of security analysis. In science and technology studies, the study of security politics adds a challenging new case to the agenda of research on expertise and policy. The contributors investigate cases such as academic security studies, security think tanks......, the collaboration between science, anthropology and the military, transnational terrorism, and the ethical consequences of security expertise. Together they challenge our understanding of how expertise works and what consequences it has for security politics and international relations. This book...... will be of particular interest to students of critical security studies, sociology, science and technology studies, and IR/security studies in general....

  14. Observation of polyphosphate granules in cable bacteria (United States)

    Yang, T.; Nielsen, L. P.; Risgaard-Petersen, N.


    Cable bacteria are long filamentous bacteria that capable for long distance electron transport: transporting electrons derived from oxidizing sulfide in anoxic layers, to oxygen at the sediment surface, over a distance of centimeters. Cable bacteria are found in many types of freshwater and marine sediment all over the world, with density of approximately thousands of kilometers per square meter. These long filaments are composed by individual cells closely related to Desulfobulbaceae, connected with a shared outer membrane inside which the strings structure are presumed to be highly conductive. The observed doubling time of cells within the filament is about 20 min, which is among the shortest compare to other bacteria. In these cable cells, we constantly observed polyphosphate granules (poly-P), regardless of cell dimension and shape. This is very interesting since it has long been recognized that the microbial polyP content is low during rapid growth and increases under unfavorable conditions, for example, increasing sulfide concentration and anoxia resulted in a decomposition of poly-P in Beggiatoa. Here, we investigated marine cable bacteria from Netherland and Aarhus Bay, focusing on the poly-P dynamics under various redox conditions. In poly-P stained cells, typically there are two big poly-P granules locate at each polar. In dividing cells, however, the morphology of poly-P changed to six small granules precisely arranged to two row. Moreover, the cells seem be able to continuously divide more than one time without elongation step. These varied poly-P morphologies demonstrate that poly-P is closely related to the cell growth and cell division, by an unknown mechanism. Individual cable filaments were picked up and were exposed to different redox conditions; our primary data indicated the cable cells could suffer anoxic condition better than oxic condition. We also detected decomposition of poly-P under anoxia. These results call for an in-depth examination

  15. Shape accuracy optimization for cable-rib tension deployable antenna structure with tensioned cables (United States)

    Liu, Ruiwei; Guo, Hongwei; Liu, Rongqiang; Wang, Hongxiang; Tang, Dewei; Song, Xiaoke


    Shape accuracy is of substantial importance in deployable structures as the demand for large-scale deployable structures in various fields, especially in aerospace engineering, increases. The main purpose of this paper is to present a shape accuracy optimization method to find the optimal pretensions for the desired shape of cable-rib tension deployable antenna structure with tensioned cables. First, an analysis model of the deployable structure is established by using finite element method. In this model, geometrical nonlinearity is considered for the cable element and beam element. Flexible deformations of the deployable structure under the action of cable network and tensioned cables are subsequently analyzed separately. Moreover, the influence of pretension of tensioned cables on natural frequencies is studied. Based on the results, a genetic algorithm is used to find a set of reasonable pretension and thus minimize structural deformation under the first natural frequency constraint. Finally, numerical simulations are presented to analyze the deployable structure under two kinds of constraints. Results show that the shape accuracy and natural frequencies of deployable structure can be effectively improved by pretension optimization.

  16. Sixty-four-Channel Inline Cable Tester (United States)


    Faults in wiring are a serious concern for the aerospace and aeronautics (commercial, military, and civil) industries. A number of accidents have occurred because faulty wiring created shorts or opens that resulted in the loss of control of the aircraft or because arcing led to fires and explosions. Some of these accidents have resulted in the massive loss of lives (such as in the TWA Flight 800 accident). Circuits on the Space Shuttle have also failed because of faulty insulation on wiring. STS-93 lost power when a primary power circuit in one engine failed and a second engine had a backup power circuit fault. Cables are usually tested on the ground after the crew reports a fault encountered during flight. Often such failures result from vibration and cannot be replicated while the aircraft is stationary. It is therefore important to monitor faults while the aircraft is in operation, when cables are more likely to fail. Work is in progress to develop a cable fault tester capable of monitoring up to 64 individual wires simultaneously. Faults can be monitored either inline or offline. In the inline mode of operation, the monitoring is performed without disturbing the normal operation of the wires under test. That is, the operations are performed unintrusively and are essentially undetectable for the test signal levels are below the noise floor. A cable can be monitored several times per second in the offline mode and once a second in the inline mode. The 64-channel inline cable tester not only detects the occurrence of a fault, but also determines the type of fault (short/open) and the location of the fault. This will enable the detection of intermittent faults that can be repaired before they become serious problems.

  17. The Cabled Component of NSF's Ocean Observatories Initiative: A Distributed, Multi-Sensor, Interactive Telepresence Within Ever-Shifting Marine Ecosystems (United States)

    Delaney, J. R.; Kelley, D. S.; Proskurowski, G. K.; Kawka, O. E.; Fundis, A.; Mulvihill, M.; Harkins, G.; Harrington, M.; McGuire, C.; Manalang, D.; Light, R.; Stewart, A.; Brand, B.


    Since mid-year 2011, NSF's Ocean Observatories Initiative has made considerable progress in installing its cabled seafloor and water-column component off the Washington-Oregon Coast. The Primary Infrastructure is nearly operational and includes ~900 km of high-power (10 kV) and bandwidth (10 Gbs) submarine electro-optical cable and 7 seafloor power- and communications switching stations (nodes) in a two-cable network spanning tectonically active zones across the Juan de Fuca Plate, with access to the overlying ocean. The system is connected to a shore-landing in Pacific City, Oregon, with a dual-path terrestrial backhaul to Portland where connections to major continent-wide, high-speed networks link via the Internet to the undersea system. During summer 2013 the VISIONS'13 expedition, using the R/V Thompson and the remotely operated vehicle (ROV) ROPOS, placed a number of secondary infrastructure elements on the seafloor, ready to be connected to the Primary Nodes when the system is fully tested and accepted by the Consortium for Ocean Leadership. Secondary infrastructure installed using the ROV ROPOS includes over 23,000 meters of extension cables, which comprise twelve electro-optical and electrical cables that provide links from the Primary Nodes to experimental sites and instrument clusters. Smaller nodes (junction boxes) were also deployed, with three installed on the seafloor. All cables and junction boxes were fully tested, which included powering up and communicating through the nodes and sensors using the ROV ROPOS as a power-communication source, and live data transmission of the resultant engineering and science data to the ship located 3000-1500m above the seafloor. Locations include sites near the base of the continental slope and on Axial Seamount, the most magmatically active volcano on the Juan de Fuca Ridge. Real-time data streamed from instruments connected to extension cables at Axial Volcano via ROPOS revealed a significant local earthquake on

  18. Simulation of power cable ohm heat by using labview

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Y. H.; Kim, J. S.; Jung, I. S. [Korea Electric Power Research Institue, Taejon (Korea, Republic of)


    Even it is necessary to consider the ohm heat of cable conductor for the evaluation of cable aging, temperature measurement of cable conductor for the evaluation of cable aging, temperature measurement of cable conductor is impractical due to untouchable condition of cable conductor which is surrounded by insulation and jacket. We have studied the way how to get the ohm heat of conductor by measuring the surface temperature of cable jacket. We verified that jacket temperature can be controlled under the 10% error limit by applying the PI control in LabView program. The relation between surface temperature of jacket and ohm heat of conductor can be predicted after this type of experiment. This study show that the ohm heat can be delivered from temperature monitoring of jacket surface.

  19. submitter On Roebel Cable Geometry for Accelerator Magnet

    CERN Document Server

    Fleiter, J; Ballarino, A


    Roebel-type cables made of a ReBCO conductor are potential candidates for high-field accelerator magnets. The necessity to promote a large effective transverse section in a Roebel cable to avoid local overstress leading to degradation in electrical performance has been recently addressed. In this paper, a new geometry of meander tapes for a Roebel cable that enhances both the transverse effective section and the current margin at crossing segments is discussed. As Roebel cables are bent at the coil ends, the modulation of the bending radius of strands along the cable pitch leads to a shift of the strands with respect to each other. The shift magnitude is analytically investigated in this paper as a function of both cable features and coil geometry. Finally, the minimum transposition pitch of Roebel cables is determined on the basis of coil characteristics.

  20. Cyber security

    CERN Document Server

    Voeller, John G


    Cyber Security features articles from the Wiley Handbook of Science and Technology for Homeland Security covering topics related to cyber security metrics and measure  and related technologies that meet security needs. Specific applications to web services, the banking and the finance sector, and industrial process control systems are discussed.

  1. Financial security

    NARCIS (Netherlands)

    de Goede, M.; Burgess, J.P.


    1. Introduction J. Peter Burgess Part 1: New Security Concepts 2. Civilizational Security Brett Bowden 3. Risk Oliver Kessler 4. Small Arms Keith Krause 5. Critical Human Security Taylor Owen 6. Critical Geopolitics Simon Dalby Part 2: New Security Subjects 7. Biopolitics Michael Dillon 8. Gendered

  2. LTE security

    CERN Document Server

    Forsberg, Dan; Moeller, Wolf-Dietrich


    Addressing the security solutions for LTE, a cellular technology from Third Generation Partnership Project (3GPP), this book shows how LTE security substantially extends GSM and 3G security. It also encompasses the architectural aspects, known as SAE, to give a comprehensive resource on the topic. Although the security for SAE/LTE evolved from the security for GSM and 3G, due to different architectural and business requirements of fourth generation systems the SAE/LTE security architecture is substantially different from its predecessors. This book presents in detail the security mechanisms em

  3. [Medical-physiological characteristics of combat training of nuclear-power submarine crews]. (United States)

    Dovgusha, V V; Myznikov, I L; Shalabodov, S A; Bumaĭ, O K


    The article presents an observe of general questions of peculiarities of military-professional activity of submarine staff These questions are defining value in ideology of medical supply of submarine troops of NAVY in now-days conditions. The article also presents the statistics of morbidity in long termed sails for last forty years, it's dynamics by different categories of sail staff, on different stages of combat training activity in dependence of perioditation of work cycle of submarine staff The authors have examined modern condition of medical supply of submarines; have presented statistics of quality indexes of health of submarine staff The authors have formed main problems of medical supply of submarines and have proposed ways of their solving on modern stage.

  4. Real-time seismic observation using new compact ocean bottom cabled system in Japan Sea (United States)

    Shinohara, M.; Kanazawa, T.; Yamada, T.; Sakai, S.; Shiobara, H.; Mochizuki, K.; Machida, Y.; Shinbo, T.; Nakahigashi, K.; Utada, H.; Yamazaki, K.


    Ocean Bottom Cabled Seismometers (OBCS), where the sensors are equipped in a hermetically-sealed case and these cases are connected with cables, is the best solution for seismic observation in marine area. A few OBCSs, consisting of a few cabled seismometers, were developed based on a submarine telecommunication cable technology, and have been used over the past 25 years in Japan. Although the existing OBCSs have realized a significant contribution to the study of seismic activity, the number of seismometers is insufficient for high resolution observations of a marine area. Therefore we developed a new OBCS system to make a high density observation in the marine areas. In Japan, GPS observations with a dense station distribution revealed that the central coastal area of the Japan Sea has large strain rate, which is named the Niigata-Kobe Tectonic Zone (NKTZ). The formation of the NKTZ is believed to be related to the plate subduction. In the NKTZ, there were several large earthquakes with magnitude greater than 7. For example, Niigata earthquake occurred in 1963, and gave large damage. Because the source region of the Niigata earthquake was located in the Japan Sea off Niigata, central Japan and the number of seismic stations of the regional seismic network was limited at the occurrence, characteristics of the earthquake have not been revealed well. There is a possibility to clarify the nature of the Niigata earthquake by detailed research of the seismic activity at the present. Therefore we decided to install the first practical OBCS system in the source area of the Niigata earthquake. The developed OBCS uses small three accelerometers as a seismic sensor. The CS is controlled by Linux system. Data collected with a time stamp at each CS are transmitted using standard IP data transmission to landing station. The network of the OBCS has redundant configuration. The electronics unit, three seismometers, power unit including zener diodes, and six SPFs are mounted into

  5. Stresses in a submarine topography under ocean waves

    Energy Technology Data Exchange (ETDEWEB)

    Mei, C.C.; McTigue, D.F.


    The problem of submarine slope stability is of interest to both offshore engineering and geology. In an uneven topography, the weight above a horizontal plane induces two-dimensional variation in the static stress field. The action of wave pressure, which changes with depth, further introduces excess pore pressure and dynamic stresses in the sea bottom. In the present paper, we combine a simple analytical theory for the static stress by the present authors, and the recent solution by Mei and Foda for wave-induced stresses in a plane poro-elastic sea bed to account for mild bottom slope and wave shoaling, to obtain the effective stress field in a submarine topography under sea waves. Sample results are given for a ridge and a canyon. In particular the dynamic pore pressure and the combined static and dynamic effective stresses are presented. 10 references, 11 figures.

  6. Stresses in a submarine topography under ocean waves

    Energy Technology Data Exchange (ETDEWEB)

    Mei, C.C.; McTigue, D.F.


    The problem of submarine slope stability is of interest to both offshore engineering and geology. In an uneven topography, the weight above a horizontal plane induces two-dimensional variation in the static stress field. The action of wave pressure, which changes with depth, further introduces excess pore pressure and dynamic stresses in the sea bottom. In the present paper, we combine a simple analytical theory for the static stress by the present authors, and the recent solution by Mei and Foda for wave-induced stresses in a plane poro-elastic sea bed to account for mild bottom slope and wave shoaling, and obtain the effective stress field in a submarine topography under sea waves. Sample results are given for a ridge and a canyon. In particular, the dynamic pore pressure and the combined static and dynamic effective stresses are presented.

  7. Improving Situational Awareness on Submarines Using Augmented Reality (United States)


    COSO ) are several pages of guidance for the evolution available to the watch officer for reference. There are also Operating Procedures that the watch...officer must follow to ensure the safe ascent to PD. The COSOs are specific to the each CO. The OPs are specific to a class of submarine. The...evolution in the framework described above can provide valuable insight to the capabilities of the proposed system. This of course is a hypothetical

  8. Analysis of SSN 688 Class Submarine Maintenance Delays (United States)


    errors an in-depth analysis into the job-level maintenance is required which is outside the scope of this analysis. 25 2. New Work Causes Late...attempting to determine the cause of this trend. Finally, this thesis proposes a solution to the systematic underestimation of availability durations by...illustrating the inherent error in the current equation and providing a notional equation to remove that error . 14. SUBJECT TERMS Submarine

  9. Submarine Pressure Hull Collapse Considering Corrosion and Penetrations (United States)


    corrosion. Des valeurs de la pression d’écrasement sont calculées pour les diverses dimensions de la zone de corrosion, et ce, dans les cas de présence ou...Research & Development Canada DRDIM Director Research and Development Knowledge and Information Management OOC Out-of-circularity R&D Research...Support SLA (Mr. John Porter) 1 Project Manager , Submarine Scientific Support SLA (LCdr Wade Temple) 9 TOTAL LIST PART I LIST PART II: External

  10. Europe’s Grand Canyon: Nazaré submarine canyon


    Tyler, P.; Amaro, T.; Arzola, R.; Cunha; Stigter, H. de; Gooday, A.; Huvenne, V.; Ingels, J; Kiriakoulakis, K; Lastras, G.; Masson, D.; Oliveira, A.; Pattenden, A.; Vanreusel, A.; van Weering, T.


    The Nazare submarine canyon extends similar to 210 km westward from the coast of Portugal, down to a water depth of > 4300 m. The considerable habitat heterogeneity found throughout the canyon is affected by strong currents and high turbidity, especially in the upper parts of the canyon. The canyon morphology comprises steep slopes, scarps, terraces, and overhangs, and a deeply incised thalweg is found in the lower part of the canyon. The seabed within the canyon is composed of varying propor...

  11. Submarine and Autonomous Vessel Proliferation: Implications for Future Strategic Stability at Sea (United States)


    replace the Ohio- class SSBN and Virginia -class SSN to replace the Los Angeles class attack submarine. Although more sophisticated than their...predecessors and with some modifications to demands of the post-Cold War era and (in the Virginia class) an emphasis on littoral conflict, these purchases...Congressional Research Service analyst Amy Woolf observes: “With few submarines in the fleet, the Navy would have to reduce the number of submarines on

  12. The future of the ballistic missile submarine force in the Russian nuclear triad


    Lesiw, Richard T.


    Approved for public release; distribution is unlimited This thesis analyzes the current status of the Russian Federation's ballistic missile submarine force. It reviews the history of the ballistic missile submarine force, its current status, and the implementation of plans currently in progress and as well as the advantages and disadvantages of maintaining a ballistic missile submarine force. This thesis also assesses the other two legs of the nuclear triad - the intercontinental balli...

  13. Gender Integration on U.S. Navy Submarines: Views of the First Wave (United States)


    submarines is to perform seek-and-destroy missions on enemy ships and submarines, conduct surveillance and reconnaissance, provide covert troop insertion...not only the missile payload they were designed to carry but also extended periods at sea without resupply. In terms of berthing and sanitary ...officer berthing and sanitary 28 facilities on board Ohio class submarines, however, no significant modifications would be necessary in order to

  14. Navy Virginia (SSN-774) Class Attack Submarine Procurement: Background and Issues for Congress (United States)


    reactors or non- nuclear power sources such as diesel engines or fuel cells. All U.S. Navy submarines are nuclear - powered. A submarine’s use of...the Navy’s plan to design and procure a next - generation ballistic missile submarine called the Ohio Replacement Program or SSBN(X). 26...the next several years require these submarines to use up their nuclear fuel cores more quickly than the Navy now projects, then the amounts of time

  15. Navy Virginia (SSN 774) Class Attack Submarine Procurement: Background and Issues for Congress (United States)


    powered attack submarines (SSNs). The SSNs are general -purpose submarines that can (when appropriately equipped and armed) perform a variety of...signs of tampering. The defective elbow pipe, used to funnel steam from the reactor to the sub’s propulsion turbines and generators , showed evidence of...Congressional Research Service Summary The Navy has been procuring Virginia (SSN-774) class nuclear- powered attack submarines since FY1998. The two Virginia

  16. Fuel-cell-propelled submarine-tanker-system study

    Energy Technology Data Exchange (ETDEWEB)

    Court, K E; Kumm, W H; O' Callaghan, J E


    This report provides a systems analysis of a commercial Arctic Ocean submarine tanker system to carry fossil energy to markets. The submarine is to be propelled by a modular Phosphoric Acid Fuel Cell system. The power level is 20 Megawatts. The DOE developed electric utility type fuel cell will be fueled with methanol. Oxidant will be provided from a liquid oxygen tank carried onboard. The twin screw submarine tanker design is sized at 165,000 deadweight tons and the study includes costs and an economic analysis of the transport system of 6 ships. The route will be under the polar icecap from a loading terminal located off Prudhoe Bay, Alaska to a transshipment facility postulated to be in a Norwegian fjord. The system throughput of the gas-fed methanol cargo will be 450,000 barrels per day. The total delivered cost of the methanol including well head purchase price of natural gas, methanol production, and shipping would be $25/bbl from Alaska to the US East Coast. Of this, the shipping cost is $6.80/bbl. All costs in 1981 dollars.

  17. Estimating the empirical probability of submarine landslide occurrence (United States)

    Geist, Eric L.; Parsons, Thomas E.; Mosher, David C.; Shipp, Craig; Moscardelli, Lorena; Chaytor, Jason D.; Baxter, Christopher D. P.; Lee, Homa J.; Urgeles, Roger


    The empirical probability for the occurrence of submarine landslides at a given location can be estimated from age dates of past landslides. In this study, tools developed to estimate earthquake probability from paleoseismic horizons are adapted to estimate submarine landslide probability. In both types of estimates, one has to account for the uncertainty associated with age-dating individual events as well as the open time intervals before and after the observed sequence of landslides. For observed sequences of submarine landslides, we typically only have the age date of the youngest event and possibly of a seismic horizon that lies below the oldest event in a landslide sequence. We use an empirical Bayes analysis based on the Poisson-Gamma conjugate prior model specifically applied to the landslide probability problem. This model assumes that landslide events as imaged in geophysical data are independent and occur in time according to a Poisson distribution characterized by a rate parameter λ. With this method, we are able to estimate the most likely value of λ and, importantly, the range of uncertainty in this estimate. Examples considered include landslide sequences observed in the Santa Barbara Channel, California, and in Port Valdez, Alaska. We confirm that given the uncertainties of age dating that landslide complexes can be treated as single events by performing statistical test of age dates representing the main failure episode of the Holocene Storegga landslide complex.

  18. Pockmark morphology and turbulent buoyant plumes at a submarine spring (United States)

    Buongiorno Nardelli, B.; Budillon, F.; Watteaux, R.; Ciccone, F.; Conforti, A.; De Falco, G.; Di Martino, G.; Innangi, S.; Tonielli, R.; Iudicone, D.


    The input flow of groundwater from the seabed to the coastal ocean, known as Submarine Groundwater Discharge (SGD), has been only recently recognized as an important component of continental margin systems. It potentially impacts physical, chemical and biological marine dynamics. Independently of its specific nature (seepage, submarine springs, etc.) or fluid chemical composition, a SGD is generally characterized by low flow rates, hence making its detection and quantification very difficult, and explaining why it has been somewhat neglected by the scientific community for a long time. Along with the growing interest for SGDs emerged the need for in-situ observations in order to characterize in details how these SGDs behave. In this work, we describe the morphology of a pockmark field, detected in the Southern Tyrrhenian Sea (Mediterranean Sea), and provide observational evidences of the presence of active submarine springs over the coastal shelf area. We describe the effect of the fluid seeps on the water column stratification close to the main plumes and in the neighbouring areas, providing quantitative estimates of the intensity of the turbulent mixing and discussing their potential impact on the seabed morphology and pockmark formation in the context of turbulent buoyant plumes analytical modelling.

  19. Long-term eruptive activity at a submarine arc volcano. (United States)

    Embley, Robert W; Chadwick, William W; Baker, Edward T; Butterfield, David A; Resing, Joseph A; de Ronde, Cornel E J; Tunnicliffe, Verena; Lupton, John E; Juniper, S Kim; Rubin, Kenneth H; Stern, Robert J; Lebon, Geoffrey T; Nakamura, Ko-ichi; Merle, Susan G; Hein, James R; Wiens, Douglas A; Tamura, Yoshihiko


    Three-quarters of the Earth's volcanic activity is submarine, located mostly along the mid-ocean ridges, with the remainder along intraoceanic arcs and hotspots at depths varying from greater than 4,000 m to near the sea surface. Most observations and sampling of submarine eruptions have been indirect, made from surface vessels or made after the fact. We describe here direct observations and sampling of an eruption at a submarine arc volcano named NW Rota-1, located 60 km northwest of the island of Rota (Commonwealth of the Northern Mariana Islands). We observed a pulsating plume permeated with droplets of molten sulphur disgorging volcanic ash and lapilli from a 15-m diameter pit in March 2004 and again in October 2005 near the summit of the volcano at a water depth of 555 m (depth in 2004). A turbid layer found on the flanks of the volcano (in 2004) at depths from 700 m to more than 1,400 m was probably formed by mass-wasting events related to the eruption. Long-term eruptive activity has produced an unusual chemical environment and a very unstable benthic habitat exploited by only a few mobile decapod species. Such conditions are perhaps distinctive of active arc and hotspot volcanoes.

  20. Automated wireless monitoring system for cable tension using smart sensors (United States)

    Sim, Sung-Han; Li, Jian; Jo, Hongki; Park, Jongwoong; Cho, Soojin; Spencer, Billie F.; Yun, Chung-Bang


    Cables are critical load carrying members of cable-stayed bridges; monitoring tension forces of the cables provides valuable information for SHM of the cable-stayed bridges. Monitoring systems for the cable tension can be efficiently realized using wireless smart sensors in conjunction with vibration-based cable tension estimation approaches. This study develops an automated cable tension monitoring system using MEMSIC's Imote2 smart sensors. An embedded data processing strategy is implemented on the Imote2-based wireless sensor network to calculate cable tensions using a vibration-based method, significantly reducing the wireless data transmission and associated power consumption. The autonomous operation of the monitoring system is achieved by AutoMonitor, a high-level coordinator application provided by the Illinois SHM Project Services Toolsuite. The monitoring system also features power harvesting enabled by solar panels attached to each sensor node and AutoMonitor for charging control. The proposed wireless system has been deployed on the Jindo Bridge, a cable-stayed bridge located in South Korea. Tension forces are autonomously monitored for 12 cables in the east, land side of the bridge, proving the validity and potential of the presented tension monitoring system for real-world applications.

  1. Offshore wind farm electrical cable layout optimization (United States)

    Pillai, A. C.; Chick, J.; Johanning, L.; Khorasanchi, M.; de Laleu, V.


    This article explores an automated approach for the efficient placement of substations and the design of an inter-array electrical collection network for an offshore wind farm through the minimization of the cost. To accomplish this, the problem is represented as a number of sub-problems that are solved in series using a combination of heuristic algorithms. The overall problem is first solved by clustering the turbines to generate valid substation positions. From this, a navigational mesh pathfinding algorithm based on Delaunay triangulation is applied to identify valid cable paths, which are then used in a mixed-integer linear programming problem to solve for a constrained capacitated minimum spanning tree considering all realistic constraints. The final tree that is produced represents the solution to the inter-array cable problem. This method is applied to a planned wind farm to illustrate the suitability of the approach and the resulting layout that is generated.

  2. Water-tree resistant cable formulations

    Energy Technology Data Exchange (ETDEWEB)

    Sarma, H.; Dobbin, C.J.B.


    Polyethylene compositions are disclosed which are suitable for use as cable insulation for high voltage power distribution cables and, more particularly, contain an additive to inhibit the propagation of water trees in the insulation. The polyethylene composition of the invention is obtained by cross-linking a composition comprising ca 95 wt % of a low-density crosslinkable polyethylene and at least 1 wt % of a hydrolyzed terpolymer of ethylene, vinyl acetate, and vinyl alcohol. The terpolymer is obtained from the at least 95% hydrolysis of an ethylene-vinyl acetate copolymer having a 20-30 wt % vinyl acetate content. The polyethylene and the terpolymer have a substantially similar melt index. Tests conducted to evaluate insulation compositions of the invention are described. 1 fig., 4 tabs.

  3. Development of polymer packaging for power cable

    Directory of Open Access Journals (Sweden)

    S. Sremac


    Full Text Available This paper discusses the issues of product design and the procedure of developing polymer packaging as one of the most important engineering tasks. For the purpose of packing power cables a polymer packaging has been designed in the form of drum. Packaging and many other consumer products are largely produced using polymeric materials due to many positive features. High Density Polyethylene is the type of polyethylene proposed for packaging purposes due to its low degree of branching and strong intermolecular forces. Transport and storage processes were automated based on the radio-frequency identification technology. The proposed system is flexible in terms of its possibility of accepting and processing different types of cables and other products.

  4. Commercialization of Medium Voltage HTS Triax TM Cable Systems

    Energy Technology Data Exchange (ETDEWEB)

    Knoll, David


    The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed the market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: • Long-length cable modeling and analysis • HTS wire evaluation and testing • Cable testing for AC losses • Optimized cooling system design • Life cycle testing of the HTS cable in Columbus, OH • Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.

  5. Biomechanical cadaveric comparison of patellar ligament suture protected by a steel cable versus a synthetic cable. (United States)

    Bouget, P; Breque, C; Beranger, J S; Faure, J P; Khiami, F; Vendeuvre, T


    Purpose and hypothesis: Patellar ligament rupture is a rare disabling pathology requiring a surgical ligament suture protected by a frame. The gold standard is the steel cable, but its rigidity and the necessity of a surgical re-intervention for its removal render it unsatisfactory. The objective of this paper is to quantify the mechanical protection provided by the terylene® in comparison with steel. Twenty-four knees of 12 fresh frozen cadaveric subjects were divided into 2 homogeneous groups (terylene and steel) of 12 knees (mean age = 69.3 years). Proximal ligament repair was performed according to a three-tunnel transosseous reinsertion technique. Mechanical tests were performed in flexion to simulate movement of the knee. The interligament gap and the amplitude angulation of the knee were measured by a system of extensometer and optical goniometer. Mechanical analysis permitted calculation of flexion amplitude for a ligament gap of 1 and 2 mm taking as initial angle the adjusting angle of pretension of the protection frame. Study of deformations of frames was performed. Statistical analysis was performed with a Wilcoxon Mann Whitney test. There is no significant difference in protection of the ligament suture between the "terylene" and "steel" groups. Mean flexion amplitudes (mΔF) show no significant differences between the 2 groups for a distension of the suture of 1 mm (m ΔF terylene1 = 4.74 °; mΔF steel1 = 5.91°; p = 0.198) and 2 mm (mΔF terylene2 = 8.71°; mΔF steel2 = 10.41°; p = 0.114). Elastic deformation of terylene was significantly greater than that of steel (p = 0.0004). Suture protection of the patellar ligament by a terylene wire is not significantly different from that provided by steel frame. The elastic properties of terylene and absence of a need for re intervention to secure its removal lead us towards its use in acute ruptures of the patellar ligament. The main limits involve the properties of

  6. Occupational Asthma in a Cable Manufacturing Company (United States)

    Attarchi, Mirsaeed; Dehghan, Faezeh; Yazdanparast, Taraneh; Mohammadi, Saber; Golchin, Mahdie; Sadeghi, Zargham; Moafi, Masoud; Seyed Mehdi, Seyed Mohammad


    Background: During the past decade, incidence of asthma has increased, which might have been due to environmental exposures. Objectives: Considering the expansion of cable manufacturing industry in Iran, the present study was conducted to evaluate the prevalence of occupational asthma in a cable manufacturing company in Iran as well as its related factors. Patients and Methods: This study was conducted on employees of a cable manufacturing company in Yazd, Iran, in 2012. The workers were divided into two groups of exposure (to toluene diisocyanate, polyvinyl chloride, polyethylene or polypropylene) and without exposure. Diagnosis of occupational asthma was made based on the subjects’ medical history, spirometry and peak flowmetry, and its frequency was compared between the two groups. Results: The overall prevalence of occupational asthma was 9.7%. This rate was 13.8% in the exposed group. Logistic regression analysis showed that even after adjustment for confounding factors, a significant correlation existed between the frequency of occupational asthma and exposure to the produced dust particles (P < 0.05). In addition, age, work experience, body mass index, cigarette smoking and shift work had significant correlations with the prevalence of occupational asthma (P < 0.05). Conclusions: Considering the high prevalence of occupational asthma among cable manufacturing company workers in Iran, this issue needs to be addressed immediately in addition to reduction of exposure among subjects. Reduction in work shift duration, implementation of tobacco control and cessation programs for the personnel, and performing spirometry tests and respiratory examinations in shorter periods may be among effective measures for reducing the incidence of occupational asthma in this industry. PMID:25558389

  7. Examining cable plant bandwidth for FDDI (United States)

    Hayes, James E.


    Networks designed around the ANSI X3T9. 5 standard called Fiber Distributed Data Interface (FDDI) are limited in distance by the bandwidth not the attenuation of the fiber optic cable. The magnitude of this limitation is defined and potential options in sources and fibers are examined. Since FDDI is limited in distance by the bandwidth of the cable plant not the attenuation many end users have put a bandwidth specification in their fiber optic cable purchase specifications. Some have even specified testing for bandwidth. This has caused much controversy between vendors installers and users. As a test equipment vendor we have " refereed" quite a few of these already and we have found that more myths are believed than realities are understood. What Limits Fiber Bandwidth? Two things limit fiber bandwidth: modal dispersion and chromatic dispersion. Modal dispersion is caused by the fact that the graded index profile of the fiber isn''t perfect so all modes do not have exactly the same transit time through the fiber. Chromatic dispersion is caused by the fact that the velocity of light in the fiber is dependent on the wavelength of the fiber. Fibers are designed for a zero dispersion wavelength light of any other wavelength will have some dispersion. Sources of wide spectral width like LEDs will suffer from more dispersion than narrow spectral width sources like laser diodes. In most circumstances one can

  8. Occupational asthma in a cable manufacturing company. (United States)

    Attarchi, Mirsaeed; Dehghan, Faezeh; Yazdanparast, Taraneh; Mohammadi, Saber; Golchin, Mahdie; Sadeghi, Zargham; Moafi, Masoud; Seyed Mehdi, Seyed Mohammad


    During the past decade, incidence of asthma has increased, which might have been due to environmental exposures. Considering the expansion of cable manufacturing industry in Iran, the present study was conducted to evaluate the prevalence of occupational asthma in a cable manufacturing company in Iran as well as its related factors. This study was conducted on employees of a cable manufacturing company in Yazd, Iran, in 2012. The workers were divided into two groups of exposure (to toluene diisocyanate, polyvinyl chloride, polyethylene or polypropylene) and without exposure. Diagnosis of occupational asthma was made based on the subjects' medical history, spirometry and peak flowmetry, and its frequency was compared between the two groups. The overall prevalence of occupational asthma was 9.7%. This rate was 13.8% in the exposed group. Logistic regression analysis showed that even after adjustment for confounding factors, a significant correlation existed between the frequency of occupational asthma and exposure to the produced dust particles (P company workers in Iran, this issue needs to be addressed immediately in addition to reduction of exposure among subjects. Reduction in work shift duration, implementation of tobacco control and cessation programs for the personnel, and performing spirometry tests and respiratory examinations in shorter periods may be among effective measures for reducing the incidence of occupational asthma in this industry.

  9. Current Injection Attack against the KLJN Secure Key Exchange

    Directory of Open Access Journals (Sweden)

    Chen Hsien-Pu


    Full Text Available The Kirchhoff-law-Johnson-noise (KLJN scheme is a statistical/physical secure key exchange system based on the laws of classical statistical physics to provide unconditional security. We used the LTSPICE industrial cable and circuit simulator to emulate one of the major active (invasive attacks, the current injection attack, against the ideal and a practical KLJN system, respectively. We show that two security enhancement techniques, namely, the instantaneous voltage/current comparison method, and a simple privacy amplification scheme, independently and effectively eliminate the information leak and successfully preserve the system’s unconditional security.

  10. Hybrid modeling for dynamic analysis of cable-pulley systems with time-varying length cable and its application (United States)

    Wang, Jing; Qi, Zhaohui; Wang, Gang


    The dynamic analysis of cable-pulley systems is investigated in this paper, where the time-varying length characteristic of the cable as well as the coupling motion between the cable and the pulleys are considered. The dynamic model for cable-pulley systems are presented based on the principle of virtual power. Firstly, the cubic spline interpolation is adopted for modeling the flexible cable elements and the virtual 1powers of tensile strain, inertia and gravity forces on the cable are formulated. Then, the coupled motions between the cable and the movable or fixed pulley are described by the input and output contact points, based on the no-slip assumption and the spatial description. The virtual powers of inertia, gravity and applied forces on the contact segment of the cable, the movable and fixed pulleys are formulated. In particular, the internal node degrees of freedom of spline cable elements are reduced, which results in that only the independent description parameters of the nodes connected to the pulleys are included in the final governing dynamic equations. At last, two cable-pulley lifting mechanisms are considered as demonstrative application examples where the vibration of the lifting process is investigated. The comparison with ADAMS models is given to prove the validity of the proposed method.

  11. 47 CFR 1.1155 - Schedule of regulatory fees and filing locations for cable television services. (United States)


    ... locations for cable television services. 1.1155 Section 1.1155 Telecommunication FEDERAL COMMUNICATIONS... Schedule of regulatory fees and filing locations for cable television services. Fee amount Address 1. Cable Television Relay Service $315 FCC, Cable, P.O. Box 979084, St. Louis, MO 63197-9000 2. Cable TV System (per...

  12. Modeling Cable and Guide Channel Interaction in a High-Strength Cable-Driven Continuum Manipulator (United States)

    Moses, Matthew S.; Murphy, Ryan J.; Kutzer, Michael D. M.; Armand, Mehran


    This paper presents several mechanical models of a high-strength cable-driven dexterous manipulator designed for surgical procedures. A stiffness model is presented that distinguishes between contributions from the cables and the backbone. A physics-based model incorporating cable friction is developed and its predictions are compared with experimental data. The data show that under high tension and high curvature, the shape of the manipulator deviates significantly from a circular arc. However, simple parametric models can fit the shape with good accuracy. The motivating application for this study is to develop a model so that shape can be predicted using easily measured quantities such as tension, so that real-time navigation may be performed, especially in minimally-invasive surgical procedures, while reducing the need for hazardous imaging methods such as fluoroscopy. PMID:27818607

  13. Antenna mechanism of length control of actin cables

    CERN Document Server

    Mohapatra, Lishibanya; Kondev, Jane


    Actin cables are linear cytoskeletal structures that serve as tracks for myosin-based intracellular transport of vesicles and organelles in both yeast and mammalian cells. In a yeast cell undergoing budding, cables are in constant dynamic turnover yet some cables grow from the bud neck toward the back of the mother cell until their length roughly equals the diameter of the mother cell. This raises the question: how is the length of these cables controlled? Here we describe a novel molecular mechanism for cable length control inspired by recent experimental observations in cells. This antenna mechanism involves three key proteins: formins, which polymerize actin, Smy1 proteins, which bind formins and inhibit actin polymerization, and myosin motors, which deliver Smy1 to formins, leading to a length-dependent actin polymerization rate. We compute the probability distribution of cable lengths as a function of several experimentally tuneable parameters such as the formin-binding affinity of Smy1 and the concentra...

  14. Guy cable design and damping for vertical axis wind turbines (United States)

    Carne, T. G.


    Guy cables are frequently used to support vertical axis wind turbines since guying the turbine reduces some of the structural requirements on the tower. The guys must be designed to provide both the required strength and the required stiffness at the top of the turbine. The axial load which the guys apply to the tower, bearings, and foundations is an undesirable consequence of using guys to support the turbine. Limiting the axial load so that it does not significantly affect the cost of the turbine is an important objective of the cable design. The lateral vibrations of the cables is another feature of the cable design which needs to be considered. These aspects of the cable design are discussed, and a technique for damping cable vibrations was mathematically analyzed and demonstrated with experimental data.

  15. Dynamic wind effects on suspension and cable-stayed bridges (United States)

    Larsen, Allan; Larose, Guy L.


    Cable supported bridges are flexible structures which may be excited into oscillations by the wind. The excitation forces acting on cable supported bridges are aerodynamic by nature, but are for a large part set into play by the underlying structural dynamics of the bridge structures. The paper discusses the various types of dynamic wind effects commonly encountered for suspension and cable-stayed bridges emphasizing the importance of the structural dynamics.

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


    Bak, Claus Leth; F. Jensen, Christian


    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 systems are being laid around the world. Differential protection is often used for the main protection of cables. As a backup protection, distance protection is very often the preferred choice. Therefore,...

  17. Watermarking security

    CERN Document Server

    Bas, Patrick; Cayre, François; Doërr, Gwenaël; Mathon, Benjamin


    This book explains how to measure the security of a watermarking scheme, how to design secure schemes but also how to attack popular watermarking schemes. This book gathers the most recent achievements in the field of watermarking security by considering both parts of this cat and mouse game. This book is useful to industrial practitioners who would like to increase the security of their watermarking applications and for academics to quickly master this fascinating domain.

  18. Node security

    CERN Document Server

    Barnes, Dominic


    A practical and fast-paced guide that will give you all the information you need to secure your Node applications.If you are a developer who wishes to secure your Node applications, whether you are already using Node Security in production, or are considering using it for your next project, then this book will enable you to ensure security of your applications. An understanding of JavaScript is a prerequisite, and some experience with Node is recommended, though not required.

  19. The Performance of Aircraft Control Cables Under Service Conditions (United States)


    wires in the cables is illustr;tcd in Ifigs. I ald 2. Fatigue tests were also carried out on samples of galvanised steel cable (5 cwt. (2.49kN) minimumil...sheave ratio using the MIL-C-151I cable of 2.38 mm (3:32 in.) diameter would have been 13.3. For a satisfactory fatigue performance for 7 x 19 galvanised ...critical region in which cable life is relatively low". Reference 13 recommends a sheave ratio of 18 for 7 x 19 galvanised and stainless ,ables and a

  20. Strand critical current degradation in $Nb_{3}$ Sn Rutherford cables

    CERN Document Server

    Barzi, E; Higley, H C; Scanlan, R M; Yamada, R; Zlobin, A V


    Fermilab is developing 11 Tesla superconducting accelerator magnets based on Nb/sub 3/Sn superconductor. Multifilamentary Nb/sub 3/Sn strands produced using the modified jelly roll, internal tin, and powder-in-tube technologies were used for the development and test of the prototype cable. To optimize the cable geometry with respect to the critical current, short samples of Rutherford cable with packing factors in the 85 to 95% range were fabricated and studied. In this paper, the results of measurements of critical current, n-value and RRR made on the round virgin strands and on the strands extracted from the cable samples are presented. (5 refs).

  1. Simulations of a moored power cable at OBSEA platform


    Prat Farran, Joana d'Arc; Río Fernandez, Joaquín del


    New green energy sources deployed at sea in mobile platforms use power cables in order to transport green energy at sea surface to the bottom. Theses power cables are exposed to the dynamic behaviour of the platform movements due to waves, currents and wind. OBSEA is a seafloor cabled observatory at 20 m depth in front of Vilanova, in Catalan coast. OBSEA captures data in real time like current, waves and wind among others. In this paper, a model of a moored power cable installed at OBS...

  2. Security Locks (United States)

    Hart, Kevin


    According to a 2008 "Year in Review" report by Educational Security Incidents, an online repository that collects data on higher education security issues, the total number of security incidents reported at universities and colleges worldwide rose to 173 in 2008, a 24.5 percent increase over 2007. The number of institutions…

  3. A PSO Driven Intelligent Model Updating and Parameter Identification Scheme for Cable-Damper System

    Directory of Open Access Journals (Sweden)

    Danhui Dan


    Full Text Available The precise measurement of the cable force is very important for monitoring and evaluating the operation status of cable structures such as cable-stayed bridges. The cable system should be installed with lateral dampers to reduce the vibration, which affects the precise measurement of the cable force and other cable parameters. This paper suggests a cable model updating calculation scheme driven by the particle swarm optimization (PSO algorithm. By establishing a finite element model considering the static geometric nonlinearity and stress-stiffening effect firstly, an automatically finite element method model updating powered by PSO algorithm is proposed, with the aims to identify the cable force and relevant parameters of cable-damper system precisely. Both numerical case studies and full-scale cable tests indicated that, after two rounds of updating process, the algorithm can accurately identify the cable force, moment of inertia, and damping coefficient of the cable-damper system.

  4. The Impact of the General Board of the Navy on Interwar Submarine Design (United States)


    Navy had developed the Gato class submarine, which was successful independently operating in the vast Pacific Ocean in support of War Plan Orange. The...development of the Gato class submarine, which was successful independently operating in the vast Pacific Ocean in support of War Plan Orange. The...

  5. Procurements by the Non-Acoustic Anti-Submarine Warfare Program Through the Environmental Technologies Laboratory (United States)


    General, DoD, on contract offloading, including Report No. 93-068, " Procurement of Services for the Non-Acoustic Anti-Submarine Warfare Program...contract administration in response to Audit Report No. 93-042. Report No. 93-068, " Procurement of Services for the Non-Acoustic Anti- Submarine Warfare

  6. Study on the locational criteria for submarine rock repositories of low and medium level radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, G. H.; Kang, W. J.; Kim, T. J. and others [Chungnam National Univ., Taejon (Korea, Republic of)


    Submarine repositories have significant advantages over their land counterparts locating close to the areas of daily human activities. Consequently, the construction of submarine repositories on the vast continental shelves around Korean seas is considered to be highly positive. In this context, the development of locational criteria primarily targeting the safety of submarine rock repositories is very important.The contents of the present study are: analyzing characteristics of marine environment: Search of potential hazards to, and environmental impact by, the submarine repositories; Investigation of the oceanographic, geochemical, ecological and sedimentological characteristics of estuaries and coastal seas. Locating potential hazards to submarine repositories by: Bibliographical search of accidents leading to the destruction of submarine structures by turbidity currents and other potentials; Review of turbidity currents. Consideration of environmental impact caused by submarine repositories: Logistics to minimize the environmental impacts in site selection; Removal and dispersion processes of radionuclides in sea water. Analyses of oceanographical characteristics of, and hazard potentials in, the Korean seas. Evaluation of the MOST 91-7 criteria for applicability to submarine repositories and the subsequent proposition of additional criteria.

  7. Submarine landslides on the north continental slope of the South China Sea (United States)

    Wang, Weiwei; Wang, Dawei; Wu, Shiguo; Völker, David; Zeng, Hongliu; Cai, Guanqiang; Li, Qingping


    Recent and paleo-submarine landslides are widely distributed within strata in deep-water areas along continental slopes, uplifts, and carbonate platforms on the north continental margin of the South China Sea (SCS). In this paper, high-resolution 3D seismic data and multibeam data based on seismic sedimentology and geomorphology are employed to assist in identifying submarine landslides. In addition, deposition models are proposed that are based on specific geological structures and features, and which illustrate the local stress field over entire submarine landslides in deep-water areas of the SCS. The SCS is one of the largest fluvial sediment sinks in enclosed or semi-enclosed marginal seas worldwide. It therefore provides a set of preconditions for the formation of submarine landslides, including rapid sediment accumulation, formation of gas hydrates, and fluid overpressure. A new concept involving temporal and spatial analyses is tested to construct a relationship between submarine landslides and different time scale trigger mechanisms, and three mechanisms are discussed in the context of spatial scale and temporal frequency: evolution of slope gradient and overpressure, global environmental changes, and tectonic events. Submarine landslides that are triggered by tectonic events are the largest but occur less frequently, while submarine landslides triggered by the combination of slope gradient and over-pressure evolution are the smallest but most frequently occurring events. In summary, analysis shows that the formation of submarine landslides is a complex process involving the operation of different factors on various time scales.

  8. The risk of hydrogen explosion in a submarine p.I Catalytic combustion of hydrogen

    Directory of Open Access Journals (Sweden)

    Kłos Ryszard


    Full Text Available The series of articles discuss issues related to conducting high risk projects on the example of modernisation of hydrogen incinerators on a submarine. The article depicts a technical problem situation connected with catalytic hydrogen combustion on a submarine.

  9. 47 CFR 76.640 - Support for unidirectional digital cable products on digital cable systems. (United States)


    ... Cable Network Interface Standard” (incorporated by reference, see § 76.602), provided however that with... reference, see § 76.602), when available from the content provider. With respect to in-band transport: (A... the transport stream. This twelve-hour period corresponds to delivery of the following event...

  10. 76 FR 77533 - Mandatory Electronic Filing for Cable Special Relief Petitions and Cable Show Cause Petitions... (United States)


    ...: This document announces the implementation of electronic filing of Cable Special Relief (CSR) Petitions... filing of CSR and CSC petitions will be permitted through January 3, 2012, when electronic filing will... Tillery of the Media Bureau at (202) 418-1056. SUPPLEMENTARY INFORMATION: This is a summary of the CSR and...

  11. Post-eruptive Submarine Terrace Development of Capelinhos, Azores (United States)

    Zhongwei Zhao, Will; Mitchell, Neil; Quartau, Rui; Tempera, Fernando; Bricheno, Lucy


    Erosion of the coasts of volcanic islands by waves creates shallow banks, but how erosion proceeds with time to create them and how it relates to wave climate is unclear. In this study, historical and recent marine geophysical data collected around the Capelinhos promontory (western Faial Island, Azores) offer an unusual opportunity to characterize how a submarine terrace developed after the eruption. The promontory was formed in 1957/58 during a Surtseyan eruption that terminated with extensive lava forming new rocky coastal cliffs. Historical measurements of coastline position are supplemented here with coastlines measured from 2004 and 2014 Google Earth images in order to characterize coastline retreat rate and distance for lava- and tephra-dominated cliffs. Swath mapping sonars were used to characterize the submarine geometry of the resulting terrace (terrace edge position, gradient and morphology). Limited photographs are available from a SCUBA dive and drop-down camera deployments to ground truth the submarine geomorphology. The results reveal that coastal retreat rates have decreased rapidly with the time after the eruption, possibly explained by the evolving resistance to erosion of cliff base materials. Surprisingly, coastline retreat rate decreases with terrace width in a simple inverse power law with terrace width. We suspect this is only a fortuitous result as wave attenuation over the terrace will not obviously produce the variation, but nevertheless it shows how rapidly the retreat rate declines. Understanding the relationship between terrace widening shelf and coastal cliff retreat rate may be more widely interesting if they can be used to understand how islands evolve over time into abrasional banks and guyots.

  12. Kinetostatic Analysis of Cable-Driven Parallel Robots with Consideration of Sagging and Pulleys


    Gouttefarde, Marc; Nguyen, Dinh Quan; Baradat, Cédric


    International audience; Cable-driven parallel robots manipulating heavy payloads typically use cables having non-negligible diameters and mass. The associated cable guiding pulleys may then have non-negligible radii whose influence on the robot kinematics can hardly be neglected. This paper focuses on the output pulleys from which the cables extend to the robot mobile platform. A kinetostatic analysis of cable-driven parallel robots considering both cable mass and output pulleys is presented.

  13. Maximizing the probability an aerial anti-submarine torpedo detects its target (United States)

    Wang, Zhi-Jie


    As a result of the high speed of anti-submarine patrol aircraft as well as their wide range, high efficiency and other characteristics, aerial torpedoes released by anti-submarine patrol aircraft have become the key anti submarine tool. In order to improve operational efficiency, a deep study was made of the target detection probabilities for aerial torpedoes released by anti-submarine patrol aircraft. The operational modes of aerial torpedoes were analyzed and mathematical-simulation models were then established. The detection probabilities of three attacking modes were then calculated. Measures were developed for improving low probabilities of detection when attacking a probable target position. This study provides an important frame of reference for the operation of aerial torpedo released by anti-submarine patrol aircraft.

  14. Two-way cable television project (United States)

    Wilkens, H.; Guenther, P.; Kiel, F.; Kraus, F.; Mahnkopf, P.; Schnee, R.


    The market demand for a multiuser computer system with interactive services was studied. Mean system work load at peak use hours was estimated and the complexity of dialog with a central computer was determined. Man machine communication by broadband cable television transmission, using digital techniques, was assumed. The end to end system is described. It is user friendly, able to handle 10,000 subscribers, and provides color television display. The central computer system architecture with remote audiovisual terminals is depicted and software is explained. Signal transmission requirements are dealt with. International availability of the test system, including sample programs, is indicated.

  15. Insulation systems for superconducting transmission cables

    DEFF Research Database (Denmark)

    Tønnesen, Ole


    This paper describes shortly the status of superconducting transmission lines and assesses what impact the recently discovered BSCCO superconductors may have on the design of the cables.Two basically different insulation systems are discussed:1) The room temperature dielectric design, where...... the electrical insulation is placed outside both the superconducting tube and the cryostat. The superconducting tube is cooled by liquid nitrogen which is pumped through the hollow part of the tube.2) The cryogenic dielectric design, where the electrical insulation is placed inside the cryostat and thus is kept...

  16. Dynamic Loadability of Cable Based Transmission Grids

    DEFF Research Database (Denmark)

    Olsen, Rasmus Schmidt

    . Kinectrics is a large consultancy who employ, among others, one of the experts within loadability calculations, Dr. George Anders. During my stay, I obtained much insight i into dynamic rating techniques, practical issues with loadability calculations and the mathematics behind. During the PhD project I...... supervised 2 master projects, as well as 5 special courses at DTU. Furthermore I created and taught a cable course, with approximately 25 students, throughout 13 weeks during the spring of 2011. The PhD project has until now contributed with 3 journal papers and 4 conference papers. Selected papers can...

  17. Main devices design of submarine oil-water separation system (United States)

    Cai, Wen-Bin; Liu, Bo-Hong


    In the process of offshore oil production, in order to thoroughly separate oil from produced fluid, solve the environment problem caused by oily sewage, and improve the economic benefit of offshore drilling, from the perspective of new oil-water separation, a set of submarine oil-water separation devices were designed through adsorption and desorption mechanism of the polymer materials for crude oil in this paper. The paper introduces the basic structure of gas-solid separation device, periodic separation device and adsorption device, and proves the rationality and feasibility of this device.

  18. Submarine glaciated landscapes of central and northern British Columbia, Canada (United States)

    Shaw, John; Lintern, Gwyn


    Recent systematic multibeam sonar mapping and ground-truthing surveys in the fjords and coastal waters of central and northern British Columbia, Canada, provide information on glacial processes associated with the Cordilleran Ice Sheet, and also on postglacial processes that have strongly modified the glacial terrain. During the last glacial maximum, ice covered the Coast Range, except for nunataks. Convergent streamlined glacial landforms in the Strait of Georgia testify to a strong flow of ice towards the southeast, between Vancouver Island and the mainland. During ice retreat, thick deposits of acoustically stratified glaciomarine mud were deposited in glacially over deepened basins. Retreat through the Douglas Channel fjord system was punctuated by still stands, resulting in a series of submarine moraines. Postglacial processes have created a suite of landforms that mask the primary glacial terrain: 1) Fjord floors host thick deposits of acoustically transparent postglacial mud with highly variable distribution: banks up to 80-m thick are commonly adjacent to erosional zones with glaciomarine mud exposed at the seafloor; 2) In this region of high precipitation and snowpack melt, numerous cone-shaped Holocene fan deltas developed on the fjord sidewalls transport coarse sediment to the fjord floors. Larger deltas are developed at fjord heads, notably at Kitimat and Kildala; 3) Submarine slope failures in this tectonically active area have resulted in a suite of mass transport deposits on sidewalls and fjord floors. The very large submarine slope failures at Camano Sound and KitKat Inlet occurred on the steep, rear facets of large transverse moraines, and involved the failure of glaciomarine sediment that moved into deeper basins, perhaps as a retrogressive failure. The ages of these events are unknown, although the presence of postglacial mud in the slide scar at Caamano suggests that the event at that location occurred in the late glacial or early Holocene. Also

  19. Experimental Investigation of Aerodynamic Instability of Iced Bridge Cable Sections

    DEFF Research Database (Denmark)

    Koss, Holger; Lund, Mia Schou Møller


    of bridge cables under wind action. This paper describes the experimental simulation of ice accretion on a real bridge cable sheet HDPE tube segment (diameter 160mm) and its effect on the aerodynamic load. Furthermore, aerodynamic instability will be estimated with quasi-steady theory using the determined...

  20. Vortex-Induced Vibration of a Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    M. T. Song


    Full Text Available The dynamic response of a cable-stayed bridge that consists of a simply supported four-cable-stayed deck beam and two rigid towers, subjected to a distributed vortex shedding force on the deck beam with a uniform rectangular cross section, is studied in this work. The cable-stayed bridge is modeled as a continuous system, and the distributed vortex shedding force on the deck beam is modeled using Ehsan-Scanlan’s model. Orthogonality conditions of exact mode shapes of the linearized undamped cable-stayed bridge model are employed to convert coupled governing partial differential equations of the original cable-stayed bridge model with damping to a set of ordinary differential equations by using Galerkin method. The dynamic response of the cable-stayed bridge is calculated using Runge-Kutta-Felhberg method in MATLAB for two cases with and without geometric nonlinear terms. Convergence of the dynamic response from Galerkin method is investigated. Numerical results show that the geometric nonlinearities of stay cables have significant influence on vortex-induced vibration of the cable-stayed bridge. There are different limit cycles in the case of neglecting the geometric nonlinear terms, and there are only one limit cycle and chaotic responses in the case of considering the geometric nonlinear terms.

  1. Levitation of Superconductive Cable in Earth Magnetic Field

    Directory of Open Access Journals (Sweden)

    Pavel Karban


    Full Text Available The paper represents an introductory study about a superconductive cable levitating in Earth’s magnetic field. Built are two mathematical models of the problem providing both the shape of the arc of the cable and forces acting along it. The theoretical analysis is supplemented with an illustrative example.

  2. 47 CFR 15.118 - Cable ready consumer electronics equipment. (United States)


    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Cable ready consumer electronics equipment. 15... Unintentional Radiators § 15.118 Cable ready consumer electronics equipment. (a) All consumer electronics TV... provisions of this section. Consumer electronics TV receiving equipment that includes features intended for...

  3. Low Friction Cryostat for HTS Power Cable of Dutch Project

    DEFF Research Database (Denmark)

    Chevtchenko, Oleg; Zuijderduin, Roy; Smit, Johan


    . A flexible dummy HTS cable was inserted into this cryostat and sub-cooled liquid nitrogen was circulated in the annulus between the dummy cable surface and the inner cryostat surface. In the paper details are presented of the cryostat, of the measurement setup, of the experiment and of the results....

  4. Chemical oxidation of cable insulating oil contaminated soil

    NARCIS (Netherlands)

    Jinlan Xu,; Pancras, T.; Grotenhuis, J.T.C.


    Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical

  5. Critical Current Measurements of the Main LHC Superconducting Cables

    CERN Document Server

    Verweij, A P


    For the main dipole and quadrupole magnets of the LHC, CERN has ordered from industry about 7000 km of superconducting Nb-Ti Rutherford type cables, delivered between 1999 and 2005. The strands of these cables are produced by six different companies, and cabled on five different machines. In the framework of the US contribution to the LHC, BNL has been testing and analyzing the electrical properties of samples of these cables. The main purpose of these tests was to qualify the critical current of the entire cable production in the frame of the quality assurance program implemented by CERN to assure the overall strand and cable performances. In total more than 2100 cable samples have been evaluated at 4.3 K in terms of critical current $I_{C}$, n-value and the residual resistance ratio, RRR. This paper will present an overview of the results, and show the correlations of the critical current and n-value between virgin strands, extracted strands, and cables. Also described are correlations of $I_{C}$ measured a...

  6. Optimized and practical electrical joints for CORC type HTS cables

    CERN Document Server

    Mulder, T; van der Laan, D C; Mentink, M G T; Dhallé, M; ten Kate, H H J


    Within CERN the development of REBCO-CORC (Conductor On Round Core) type cables is pursued in view of possible application in future detector and accelerator magnets. An important issue is the design and qualification of terminations for connecting CORC cables mutually or to bus-bars. A termination design is envisaged that combines a simple manufacturing process with a lowest possible joint terminal resistance in the few nΩ range at 4.2 K, first for a single CORC cable and subsequently for CORC based Cable-in-Conduit Conductors. The investigation concerns the effect of tapering the CORC cable within the joint to form a staircase like geometry, which allows current to pass more directly from the copper joint casing to the inner REBCO layers of the CORC cable. Simulations have shown a substantial decrease in joint resistance at operating current in the case both CORC cable and joint casing are tapered. The CORC cable and new joint were tested at CERN. In this paper, some details of the new joint design, fabric...

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

    DEFF Research Database (Denmark)

    Bak, Claus Leth; F. Jensen, Christian


    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...

  8. Metal flame spray coating protects electrical cables in extreme environment (United States)

    Brady, R. D.; Fox, H. A.


    Metal flame spray coating prevents EMF measurement error in sheathed instrumentation cables which are externally attached to cylinders which were cooled on the inside, but exposed to gamma radiation on the outside. The coating provides a thermoconductive path for radiation induced high temperatures within the cables.

  9. Analyses Of High Voltage Transmission Cables In South Western ...

    African Journals Online (AJOL)

    This paper presents the report of an investigation of the electrical and structural integrity of overhead and underground electrical cables in the south western part of Nigeria. Overhead and underground transmission cables were collected around the Obafemi Awolowo University environment, melted and cast into cylindrical ...

  10. Modeling and simulation of HTS cables for scattering parameter analysis

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Su Sik; Lee, Geon Seok; Kwon, Gu-Young; Lee, Yeong Ho; Chang, Seung Jin; Lee, Chun-Kwon [School of Electrical and Electronic Engineering, Yonsei University, Seoul, 03772 (Korea, Republic of); Sohn, Songho; Park, Kijun [Korea Electric Power Corporation Research Institute, Daejeon, 34056 (Korea, Republic of); Shin, Yong-June, E-mail: [School of Electrical and Electronic Engineering, Yonsei University, Seoul, 03772 (Korea, Republic of)


    Most of modeling and simulation of high temperature superconducting (HTS) cables are inadequate for high frequency analysis since focus of the simulation’s frequency is fundamental frequency of the power grid, which does not reflect transient characteristic. However, high frequency analysis is essential process to research the HTS cables transient for protection and diagnosis of the HTS cables. Thus, this paper proposes a new approach for modeling and simulation of HTS cables to derive the scattering parameter (S-parameter), an effective high frequency analysis, for transient wave propagation characteristics in high frequency range. The parameters sweeping method is used to validate the simulation results to the measured data given by a network analyzer (NA). This paper also presents the effects of the cable-to-NA connector in order to minimize the error between the simulated and the measured data under ambient and superconductive conditions. Based on the proposed modeling and simulation technique, S-parameters of long-distance HTS cables can be accurately derived in wide range of frequency. The results of proposed modeling and simulation can yield the characteristics of the HTS cables and will contribute to analyze the HTS cables.

  11. Double Layered Sheath in Accurate HV XLPE Cable Modeling

    DEFF Research Database (Denmark)

    Gudmundsdottir, Unnur Stella; Silva, J. De; Bak, Claus Leth


    This paper discusses modelling of high voltage AC underground cables. For long cables, when crossbonding points are present, not only the coaxial mode of propagation is excited during transient phenomena, but also the intersheath mode. This causes inaccurate simulation results for high frequency...

  12. Cable route optimization for offshore wind farms in morphodynamic areas

    NARCIS (Netherlands)

    Roetert, T.J.; Raaijmakers, T.; Borsje, Bastiaan Wijnand


    The aim of this paper is to optimize power cable routing in a wind farm based on the expected morphological behaviour in the design lifetime of an offshore wind farm. Up to now methods to optimize cable route layout in offshore wind farms are only based on a flat seabed and do not take the seabed

  13. Surface Plasmons in Coaxial Metamaterial Cables (United States)

    Kushwaha, Manvir S.; Djafari-Rouhani, Bahram


    Thanks to Victor Veselago for his hypothesis of negative index of refraction, meta-materials — engineered composites — can be designed to have properties difficult or impossible to find in nature: they can have both electrical permittivity (ɛ) and magnetic permeability (μ) simultaneously negative. The metamaterials — henceforth negative-index materials (NIMs) — owe their properties to subwavelength structure rather than to their chemical composition. The tailored electromagnetic response of the NIMs has had a dramatic impact on classical optics: they are becoming known to have changed many basic notions related with electromagnetism. The present article is focused on gathering and reviewing fundamental characteristics of plasmon propagation in coaxial cables fabricated of the right-handed medium (RHM) (with ɛ > 0, μ > 0) and the left-handed medium (LHM) (with ɛ cloaking devices in particular. A recent surge in efforts on invisibility and the cloaking devices seems to have spoiled the researchers worldwide: proposals include not only a way to hide an object without having to wrap the cloak around it, but also to replace a given object with another, thus adding to the deception even further! All this is attributed as much to the fundamental as to the practical advances made in the fabrication and characterization of NIMs. The article concludes briefly addressing the anticipated implications of plasmon observation in the multicoaxial cables and suggesting future dimensions worth adding to the problem. The background provided is believed to make less formidable the task of future writers of reviews in this field.

  14. The Offshore Wind Farm Array Cable Layout Problem

    DEFF Research Database (Denmark)

    Bauer, Joanna; Lysgaard, Jens


    In an offshore wind farm (OWF), the turbines are connected to a transformer by cable routes that cannot cross each other. Finding the minimum cost array cable layout thus amounts to a vehicle routing problem with the additional constraints that the routes must be embedded in the plane. For this p......In an offshore wind farm (OWF), the turbines are connected to a transformer by cable routes that cannot cross each other. Finding the minimum cost array cable layout thus amounts to a vehicle routing problem with the additional constraints that the routes must be embedded in the plane....... For this problem, both exact and heuristic methods are of interest. We optimize cable layouts for real-world OWFs by a hop-indexed integer programming formulation, and develop a heuristic for computing layouts based on the Clarke and Wright savings heuristic for vehicle routing. Our heuristic computes layouts...

  15. Non-Intrusive Impedance-Based Cable Tester (United States)

    Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)


    A non-intrusive electrical cable tester determines the nature and location of a discontinuity in a cable through application of an oscillating signal to one end of the cable. The frequency of the oscillating signal is varied in increments until a minimum, close to zero voltage is measured at a signal injection point which is indicative of a minimum impedance at that point. The frequency of the test signal at which the minimum impedance occurs is then employed to determine the distance to the discontinuity by employing a formula which relates this distance to the signal frequency and the velocity factor of the cable. A numerically controlled oscillator is provided to generate the oscillating signal, and a microcontroller automatically controls operation of the cable tester to make the desired measurements and display the results. The device is contained in a portable housing which may be hand held to facilitate convenient use of the device in difficult to access locations.

  16. First International Conference on Cable-Driven Parallel Robots

    CERN Document Server

    Pott, Andreas; Cable-Driven Parallel Robots


    This publication presents the outcome of the "First International Conference on Cable-Driven Parallel Robots" in 2012. This is the first conference to bring together the cable robot community and dedicate a forum for the international experts of this field. It contains the Know-how, ideas and experiences of active researchers developing cable-driven robots. The book presents the state of the art, including summarizing contributions and latest research results and, where relevant, the future outlook. The book covers the essential topics for cable-driven robots: classification and definition, kinematics, workspace analysis, cable modeling, control and calibration, design methodology, hardware/prototype development, experimental evaluation, application reports and new application concepts.

  17. Life-assessment technique for nuclear power plant cables

    Energy Technology Data Exchange (ETDEWEB)

    Bartonicek, B.; Hnat, V.; Placek, V


    The condition of polymer-based cable material can be best characterized by measuring elongation at break of its insulating materials. However, it is not often possible to take sufficiently large samples for measurement with the tensile testing machine. The problem has been conveniently solved by utilizing differential scanning calorimetry technique. From the tested cable, several microsamples are taken and the oxidation induction time (OIT) is determined. For each cable which is subject to the assessment of the lifetime, the correlation of OIT with elongation at break and the correlation of elongation at break with the cable service time has to be performed. A reliable assessment of the cable lifetime depends on accuracy of these correlations. Consequently, synergistic effects well known at this time - dose rate effects and effects resulting from the different sequence of applying radiation and elevated temperature must be taken into account.

  18. Ground Loop Impedance of Long EHV Cable Lines

    DEFF Research Database (Denmark)

    Ohno, Teruo; Bak, Claus Leth; Sørensen, Thomas K.


    The distance protection scheme without communication is often applied to the backup protection of EHV cable lines. For a reliable operation of a ground distance relay, the ground loop impedance of EHV cable lines needs to have a linear relationship to the distance from the relay location...... to the fault location. The discontinuity of the ground loop impedance at cross-bonding points may have an ill effect on the reliable operation of the ground distance relay. However, the cause and parameters of the discontinuity and its effects on the ground distance relay protection have not been discussed...... in literature. Through the calculation of the ground loop impedance for cable lines, it has been found that, for long EHV cable lines, the reliable operation of the ground distance relay is possible with a typical relay setting. Effects of parameters, such as substation grounding, cable layouts...

  19. A dc transmission cable prototype using high-temperature superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Beales, T.P.; Friend, C.M. [BICC Cables Ltd, Hedgeley Road, Hebburn, Tyne and Wear NE31 1XR (United Kingdom); Segir, W.; Ferrero, E. [Ceat Cavi Industrie srl, Via Brescia 16, 10036 Settimo Torinese (Italy); Vivaldi, F.; Ottonello, L. [Ansaldo Ricerche srl, Corso Perrone 25, 16161 Genoa (Italy)


    This paper gives the results from a recent collaboration between BICC Cables Ltd, its Italian subsidiary Ceat Cavi srl, and Ansaldo Ricerche srl on the design and testing of a high-temperature superconducting dc transmission cable prototype. The cable was designed to carry 10 000 A at 40 kV, operating at 40 K. Qualification testing was carried out from 4.2 K up to 40 K. At an operating temperature of 31 K the prototype cable had a current capacity of 11 067 A (the largest dc current reported in a high-temperature prototype to date), which represents a tenfold increase in current over a conventional 1000 mm{sup 2} copper cable. (author)

  20. Time-Lapse Electrical Resistivity Surveys of the Intertidal Zone: Implications for Submarine Groundwater Discharge (United States)

    Durand, J. M.; Wong, T.


    Submarine groundwater discharge (SGD) is now widely recognized as a crucial contributor to surface water as it provides a pathway for nutrients and contaminants that can significantly impact coastal ecosystems. Field measurements in the vicinity of the freshwater/seawater interface (FSI) have shown that the spatio-temporal distribution of SGD can be highly heterogeneous. Some numerical models have identified 3 regions (a density-driven circulation cell offshore, an upper saline plume and a freshwater tube in the intertidal zone) which seem to persist over time, such that the distinct regions can be recognized in simulations that average the numerically predicted salinity profiles over the tidal phases. The size and shape of each region are influenced by factors such as the tidal and wave loading, inland hydraulic gradient, beach geometry and aquifer properties. There is a paucity of field data at the FSI on the evolution of the salinity profile during a tidal cycle. To characterize the spatio-temporal heterogeneities of the FSI and compare with numerical predictions, we used electrical resistivity as a proxy for salinity. Electrical resistivity surveys were acquired during a 12-hour cycle in a tidally dominated environment. On September 12 2012, at West Neck Bay (Shelter Island, NY), a 33.4 m long stationary cable with 56 electrodes was extended over land and sea to image the intertidal zone. Hourly measurements were conducted over a full tidal cycle. Our measurements indicate fundamentally different scenarios during high and low tide. At low tide, our resistivity data suggest a strong influx of freshwater from land, forming a plume that rises up and contributes significantly to SGD in the intertidal zone. We also observed the occurrence of 3 regions somewhat analogous to the numerical predictions. However, at high tide, instead of these distinct regions, we observed a diffuse mixing zone that extended along the water/sediment interface and overlaid the freshwater

  1. Seismicity and sedimentation rate effects on submarine slope stability (United States)

    Ten Brink, U. S.; Andrews, B. D.; Miller, N. C.


    Large submarine mass-transport scars are commonly observed on continental margins, but are noticeably less abundant on margins that experience frequent earthquakes than on those that seldom experience them. This is a surprising observation, given that horizontal acceleration from earthquakes and associated strength loss from cyclic loading and liquefaction are commonly thought to provide the primary triggers for inducing failures and subsequent mass movements. Mapping submarine failure scars in ten margins worldwide, we find decreasing scar abundance with both increasing frequency of earthquakes and decreasing sedimentation rate. The decrease in scar abundance is interpreted to represent increasing slope stability. The increase in stability is non linear (power law with btectonic activity (salt diapirs, seamount subduction, etc.) leads to relatively rapid oversteepening of the slope, implying that the morphology of most margins is in fact, stable over many earthquake cycles. Note that the above correlation averages scar area and sedimentation rate over entire margin areas. Variations in sedimentation rate with time, such as over glacial-interglacial cycles, and intra-margin variations in seismic attenuation, sedimentation rate, composition, and pore pressure, have likely affected the abundance of slope failures in time and space.

  2. An Automatic Procedure for the Quantitative Characterization of Submarine Bedforms

    Directory of Open Access Journals (Sweden)

    Massimo Di Stefano


    Full Text Available A model for the extraction and quantitative characterization of submarine landforms from high-resolution digital bathymetry is presented. The procedure is fully automated and comprises two parts. The first part consists of an analytical model which extracts quantitative information from a Digital Elevation Model in the form of objects with similar parametric characteristics (terrain objects. The second part is a rule-based model where the terrain objects are reclassified into distinct landforms with well-defined three dimensional characteristics. For the focus of this work, the quantitative characterization of isolated dunes (height greater than 2 m is used to exemplify the process. The primary metrics used to extract terrain objects are the flatness threshold and the search radius, which are then used by the analytical model to identify the feature type. Once identified as dunes, a sequence of spatial analysis routines is applied to identify and compute metrics for each dune including length, height, width, ray of curvature, slope analysis for each stoss and lee side, and dune symmetry. Dividing the model into two parts, one scale-dependent and another centered around the shape of the landform, makes the model applicable to other submarine landforms like ripples, mega-ripples, and coral reefs, which also have well-defined three-dimensional characteristics.

  3. Fin propulsion on a human-powered submarine (United States)

    Anderson, Iain A.; Pocock, Benjamin; Harbuz, Antoni; Algie, Cam; Vochezer, Daniel; Chao, Ryan; Lu, Benjamin


    Nearly all surface and underwater vessels are driven by screw propulsion; ideal for coupling to rotary engines and well understood after over a century of development. But most aquatic creatures use fins for swimming. Although there are sound evolutionary reasons why fish have fins and not propellers, they are nevertheless agile, fast and efficient. Although fish-like robots such as the MIT Robotuna are providing good insight into fin-based swimming there are advantages for using humans in the experimental device. Like an airplane test pilot they can write crash reports. We present preliminary observations for the human powered finned submarine: Taniwha. The sub participated in the 2nd European International Submarine races in Gosport UK where it received a trophy for "Best Non-Propeller Performance". Two sets of Hobie Mirage fin drives fixed to the upper and lower rear surfaces of the sub are pedaled by the pilot. The pilot also has two levers at the front, one to pitch a pair of dive planes and one for yawing a large rudder. Good speed, we estimate to be greater than 6 m/s is possible with these fins although we haven't explored their full potential. Straying too near the surface or bottom can lead to an instability, synonymous to a stall, such that control is lost. The mechanism for this will be discussed and solutions offered. Fish are 400 million years in front of us but one day we'll catch them.

  4. Are tilt measurements useful in detecting tsunamigenic submarine landslides? (United States)

    Brune, Sascha; Babeyko, Andrey Y.; Sobolev, Stephan V.


    Large submarine landslides can generate dangerous tsunamis. Because of their long-period signal, detection of landslides by common seismological methods is difficult. Here we suggest a method of detecting submarine landslides by using an array of land-based tiltmeters. The displacement of a large volume of sediments during landsliding produces a detectable elastic response of the lithosphere. We propose a technique to calculate this response and to invert for tsunami relevant parameters like slide location, volume, and velocity. We exemplify our method by applying it to the Storegga slide west of Norway and other tsunamigenic landslide events. The parameter which can be most robustly estimated from tiltmeter array measurements is the product of slide volume and its velocity (slide tsunamigenic potential). This parameter also controls the amplitude of the generated tsunami wave. The inversion accuracy of this parameter and the estimated tsunami height near the coast depends on the noise level of tiltmeter measurements, distance of the tiltmeters from the slide, and slide tsunamigenic potential itself. The tsunamigenic potential of the most dangerous slides like Storegga can be estimated well by tiltmeters at the coast if the effective noise level does not exceed 50 nrad.

  5. A submarine fan in the Mesa Central, Mexico (United States)

    Silva-Romo, G.; Arellano-Gil, J.; Mendoza-Rosales, C.; Nieto-Obregón, J.


    The contact between the Guerrero and Sierra Madre tectonostratigraphic terranes has been proposed to lie in the Mesa Central, east of the city of Zacatecas. Marine Triassic units have been assigned to the Guerrero Terrane. It is here proposed that this contact occurs to the west of the city of Zacatecas and the Triassic marine sequence assigned to the Sierra Madre Terrane. We analyzed the stratigraphic record and structural features of pre-Late Jurassic sequences at four localities in the Mesa Central. They contain a marine turbiditic Triassic unit, which includes La Bellena, Taray, and Zacatecas Formations, and a continental unit of probable Middle Jurassic age. Triassic sandstones were derived from a cratonic area, without the influence of arc volcanism. The sequences were affected by two phases of deformation. The Triassic formations are unconformably overlain by a continental volcano-sedimentary sequence that contains fragments of sandstones derived from the underlying unit. Sedimentologic characteristics of the Triassic unit fit a submarine fan model. The submarine fan developed at the continental margin of Pangaea during Triassic times. Turbidite associations in the San Rafael Area indicate a middle fan depositional environment, while in the Real de Catorce Area, they correspond to the distal part (basin plain facies). At La Ballena and Zacatecas the turbidite associations occur in the middle part and perhaps the external part of the fan.

  6. Feasibility study of submarine diesel exhaust valve interspace coating application

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, W.; Zhou, M.; Bibby, D.; Huang, J.


    This document described a feasibility study conducted to evaluate surface coating systems applied to the surface of a diesel exhaust valve interspace on a VICTORIA Class submarine. A series of laboratory studies were conducted to determine the physical characteristics of the coatings, which will be subjected to high service temperatures, diesel exhaust gas, and seawater. The valves were made of Q1N steel castings. The surface coatings were designed to provide corrosion resistance and thermal protection to the valves. As part of the study, a survey was conducted on various state-of-the-art surface coating systems. Coatings were rated on their ability to protect the Q10 steel surface from corrosion, high temperatures and seawater. An additional requirement was that the coatings should not produce high amounts of hydrogen. Plating trials were conducted with a nickel-based alloy (Ni-Cu-P) placed on Q1N steel substrates with a hypophosphite reducing agent. The results of X-ray diffraction (XRD) analyses suggested that the coatings can also be used to protect the external surfaces of various submarine components. 54 refs., 4 tabs., 10 figs.

  7. Grid Security

    CERN Multimedia

    CERN. Geneva


    The aim of Grid computing is to enable the easy and open sharing of resources between large and highly distributed communities of scientists and institutes across many independent administrative domains. Convincing site security officers and computer centre managers to allow this to happen in view of today's ever-increasing Internet security problems is a major challenge. Convincing users and application developers to take security seriously is equally difficult. This paper will describe the main Grid security issues, both in terms of technology and policy, that have been tackled over recent years in LCG and related Grid projects. Achievements to date will be described and opportunities for future improvements will be addressed.

  8. Securing Hadoop

    CERN Document Server

    Narayanan, Sudheesh


    This book is a step-by-step tutorial filled with practical examples which will focus mainly on the key security tools and implementation techniques of Hadoop security.This book is great for Hadoop practitioners (solution architects, Hadoop administrators, developers, and Hadoop project managers) who are looking to get a good grounding in what Kerberos is all about and who wish to learn how to implement end-to-end Hadoop security within an enterprise setup. It's assumed that you will have some basic understanding of Hadoop as well as be familiar with some basic security concepts.

  9. Development of the Database of Cables of Almaraz NPP as the fire deterministic analysis support; Elaboracion de la base de datos de cables de C.N. Almaraz como soporte de los analisis deterministas de incendios

    Energy Technology Data Exchange (ETDEWEB)

    Villar Sanchez, T.; Fernandez Ramos, P.; Garcia Romero, A.; Fuente Prieto, I.


    Within the process of transition to the NFPA-805, it requires a deterministic analysis of fire, for which it is necessary, on the one hand, the identification and location of the cables and equipment necessary and important for achieve and maintain safe, and stop on the other hand, the analysis of the different types of spurious multiple, based on the methodology described in the NEI 00-01 Rev. 2. the base Almaraz NPP cables data it collects this information and is a fundamental tool to analyze the capacity of the plant to achieve the stop safe in case of fire, which allows you to find possible vulnerabilities and take appropriate measures to improve the security of it.

  10. Improved practical formulas for estimation of cable tension by vibration method; Shindoho ni yoru cable choryoku jitsuyo santeishiki no hosei

    Energy Technology Data Exchange (ETDEWEB)

    Zui, H. [Setsunan University, Osaka (Japan). Faculty of Engineering; Shinke, T. [Kobe Technical College, Kobe, Kobe (Japan); Hamazaki, Y. [Kobe Steel, Ltd., Kobe (Japan)


    The vibration method is usually utilized on the measurement of cable tension during construction of cable bridge such as Nielsen bridges or cable stayed bridges. Practical formula for the vibration method previously proposed by authors is often used where bending rigidity is taken into account. These formula, however, have a certain limit of application and do not yield good results when the cable is not slender or not enough mentioned. The practical formula is modified to improve the accuracy and new formulas are made. The new practical formulas are applicable to any cables, regardless of its length and tension in it. The accuracy is confirmed through comparison of the value obtained by practical formulas with measured values and calculated value by F.E.M. 2 refs., 4 figs., 1 tab.

  11. Design of anti-theft/cable cut real time alert system for copper cable using microcontroller and GSM technology (United States)

    Lim, E. K.; Norizan, M. N.; Mohamad, I. S.; Yasin, M. N. M.; Murad, S. A. Z.; Baharum, N. A.; Jamalullail, N.


    This paper presents the design of anti-theft/cable cut real time alert system using microcontroller and GSM technology. The detection part is using the electrical circuit wire connection in detecting the voltage drop of the cable inside the microcontroller digital input port. The GSM wireless modem is used to send the location of cable cut directly to the authority mobile phone. Microcontroller SK40C with Microchip PIC16F887 is used as a controller to control the wireless modem and also the detection device. The device is able to detect and display the location of the cable cut on the LCD display besides of and sending out the location of the cable break to the authority mobile phone wirelessly via SMS.

  12. Aerodynamics of the cable of cable-stayed bridges; Shachokyo cable no kuriki shindo tokusei no rikai to soreni motozuku kuriki seishinho no teian

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, M. [Kyoto University, Kyoto (Japan). Faculty of Engineering; Aoki, J.; Fuji, D. [West Japan Railway Company, Osaka (Japan); Kitayama, N. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan); Daito, Y. [Kyoto University, Kyoto (Japan)


    Wind tunnel tests were conducted assuming the aerodynamics of the cable of cable-stayed bridges especially in the case of strong wind with rain. Based on the results, an aerodynamic damping method was proposed. Factors of the rain vibration generation include the three-dimensional axial flow behind the cable, which is formed by the wind direction deviation angle, the upper side water flow on the cable surface formed by the rain, and the Karman vortex shedding, which are not uniform in the span direction. Newly proposed cable with elliptical plates showed an effective dumping performance. It restrains the formation of water flow due to its profile, and is effective for unstableness due to water flow formation. Distribution of the axial flow in the cable span direction was made clear. Three-dimensionality of the vortex shedding was greatly affected by this axial flow. Frequency of the Karman vortex shedding changed in the wide band by the axial flow. It was suggested that three-dimensionality of the flow field is enhanced by the rolling vibration, resulting in the unstableness of heaving vibration. 5 refs., 15 figs.

  13. Occupational stress in submariners: the impact of isolated and confined work on psychological well-being. (United States)

    Brasher, Kate S; Dew, Angela B C; Kilminster, Shaun G; Bridger, Robert S


    This study aimed to identify work-related and personal factors associated with occupational stress in submariners. Work and well-being questionnaires were distributed to 219 male submariners (mean age 34 years), as part of a larger cohort study involving a stratified sample of 4951 Royal Navy (RN) personnel. The stress rate in submariners was 40%; significantly higher than the stress rate in the general RN, although once demographic factors were controlled for in a matched control sample, this difference was no longer significant. A summary model accounted for 49% of the variance in submariner stress, with key differences emerging between the occupational factors associated with stress in submariners and in the general RN. The longitudinal nature of this study permits stress in submariners to be monitored over 5 years, which will provide valuable insights into the chronicity of stress in this specialised occupational group. STATEMENT OF RELEVANCE: This paper contributes to the current literature on the negative impact of working in isolated conditions. It is demonstrated that occupational stress in submarines can be partially explained using current theories of stress in the workplace. However, the constraints of a restricted environment introduce additional factors which can also be associated with occupational stress.

  14. Measuring currents in submarine canyons: technological and scientific progress in the past 30 years (United States)

    Xu, J. P.


    The development and application of acoustic and optical technologies and of accurate positioning systems in the past 30 years have opened new frontiers in the submarine canyon research communities. This paper reviews several key advancements in both technology and science in the field of currents in submarine canyons since the1979 publication of Currents in Submarine Canyons and Other Sea Valleys by Francis Shepard and colleagues. Precise placements of high-resolution, high-frequency instruments have not only allowed researchers to collect new data that are essential for advancing and generalizing theories governing the canyon currents, but have also revealed new natural phenomena that challenge the understandings of the theorists and experimenters in their predictions of submarine canyon flow fields. Baroclinic motions at tidal frequencies, found to be intensified both up canyon and toward the canyon floor, dominate the flow field and control the sediment transport processes in submarine canyons. Turbidity currents are found to frequently occur in active submarine canyons such as Monterey Canyon. These turbidity currents have maximum speeds of nearly 200 cm/s, much smaller than the speeds of turbidity currents in geological time, but still very destructive. In addition to traditional Eulerian measurements, Lagrangian flow data are essential in quantifying water and sediment transport in submarine canyons. A concerted experiment with multiple monitoring stations along the canyon axis and on nearby shelves is required to characterize the storm-trigger mechanism for turbidity currents.


    Billitti, J. W.


    A computerized interactive harness engineering program has been developed to provide an inexpensive, interactive system which is designed for learning and using an engineering approach to interconnection systems. PCACE is basically a database system that stores information as files of individual connectors and handles wiring information in circuit groups stored as records. This directly emulates the typical manual engineering methods of data handling, thus making the user interface to the program very natural. Data files can be created, viewed, manipulated, or printed in real time. The printed ouput is in a form ready for use by fabrication and engineering personnel. PCACE also contains a wide variety of error-checking routines including connector contact checks during hardcopy generation. The user may edit existing harness data files or create new files. In creating a new file, the user is given the opportunity to insert all the connector and harness boiler plate data which would be part of a normal connector wiring diagram. This data includes the following: 1) connector reference designator, 2) connector part number, 3) backshell part number, 4) cable reference designator, 5) cable part number, 6) drawing revision, 7) relevant notes, 8) standard wire gauge, and 9) maximum circuit count. Any item except the maximum circuit count may be left blank, and any item may be changed at a later time. Once a file is created and organized, the user is directed to the main menu and has access to the file boiler plate, the circuit wiring records, and the wiring records index list. The organization of a file is such that record zero contains the connector/cable boiler plate, and all other records contain circuit wiring data. Each wiring record will handle a circuit with as many as nine wires in the interface. The record stores the circuit name and wire count and the following data for each wire: 1) wire identifier, 2) contact, 3) splice, 4) wire gauge if different from standard

  16. Information security management handbook

    CERN Document Server

    Tipton, Harold F


    Access Control Systems and Methodology. Telecommunications and Network Security. Security Management Practices. Application Program Security. Cryptography. Computer, System, and Security Architecture. Operations Security. Business Continuity Planning and Disaster Recovery Planning. Law, Investigation and Ethics. Physical Security.

  17. Submarine seismic monitoring of El Hierro volcanic eruption with a 3C-geophone string: applying new acquisition and data processing techniques to volcano monitoring (United States)

    Jurado, Maria Jose; Ripepe, Maurizio; Lopez, Carmen; Blanco, Maria Jose; Crespo, Jose


    A submarine volcanic eruption took place near the southernmost emerged land of the El Hierro Island (Canary Islands, Spain), from October 2011 to February 2012. The Instituto Geografico Nacional (IGN) seismic stations network evidenced seismic unrest since July 2011 and was a reference also to follow the evolution of the seismic activity associated with the volcanic eruption. Right after the eruption onset, in October 2011 a geophone string was deployed by the CSIC-IGN to monitor seismic activity. Monitoring with the seismic array continued till May 2012. The array was installed less than 2 km away from the new vol¬cano, next to La Restinga village shore in the harbor from 6 to 12m deep into the water. Our purpose was to record seismic activity related to the volcanic activity, continuously and with special interest on high frequency events. The seismic array was endowed with 8, high frequency, 3 component, 250 Hz, geophone cable string with a separation of 6 m between them. Each geophone consists on a 3-component module based on 3 orthogonal independent sensors that measures ground velocity. Some of the geophones were placed directly on the seabed, some were buried. Due to different factors, as the irregular characteristics of the seafloor. The data was recorded on the surface with a seismometer and stored on a laptop computer. We show how acoustic data collected underwater show a great correlation with the seismic data recorded on land. Finally we compare our data analysis results with the observed sea surface activity (ash and lava emission and degassing). This evidence is disclosing new and innovative tecniques on monitoring submarine volcanic activity. Reference Instituto Geográfico Nacional (IGN), "Serie El Hierro." Internet: /volcanologia/HIERRO.html [May, 17. 2013

  18. Prediction of nuclear submariner adaptability from autonomic indices and Rorschach Inkblot responses. Interim report

    Energy Technology Data Exchange (ETDEWEB)

    Weybrew, B.B.; Molish, H.B.


    To identify the most valid predictors of submariner adaptability, the authors derived 23 indices from the responses of 170 nuclear submariners to the Rorschach Inkblot Test, 11 measures of Autonomic Nervous System (ANS) reactivity to contrived stress, and five adjustment criteria. Factor analysis of this 39x39 correlation matrix yielded two Rorschach Factors, one of which correlated with three criterion dimensions. Two unique factors were also discovered, one, a structured ANS factor, and the other, a complex criterion scale. Selected Rorschach scores and, to a lesser extent, certain ANS indices emanating from this study, may be usefully-valid predictors of the adaptability of nuclear submariners during long patrols.

  19. Longest cable-stayed bridge TATARA; Longest shachokyo Tatara Ohashi

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, K. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering


    The world`s longest cable-stayed bridge Tatara having a central span of 890 m had the both ends closed in August 1997, linking Namakuchi Island and Omishima Island. Final finishing work is continuing for opening of the West Seto Expressway in the spring of 1999. A cable-stayed bridge supports the bridge girders by perpendicular components of tensile force of cables stayed obliquely. On the other hand, there is a concern that the girders may have axial compression force generated due to horizontal components of the force from the cable tensile force, which can cause buckling of the girders. Therefore, in order to suspend the girders efficiently by increasing the perpendicular components of the cable force, and moreover to suppress the axial compression force on the girders, it is more advantageous to make bridge towers high, hence the towers of this bridge are highest among the bridges on the Shimanami Ocean Road. This bridge whose long girders are stayed with 21-stage multi cables presented a problem in designing the buckling in steel girders near the towers due to the horizontal components of the force generated by the bridge. Discussions were given, therefore, by using load withstanding force experiments using a whole bridge model of 1/50 scale, buckling experiments on full-size reinforcing plate models, and load withstanding force analysis using a tower model. A number of other technical discussions were repeated, by which the world`s longest cable-stayed bridge was completed. 9 figs., 1 tab.

  20. Antenna Mechanism of Length Control of Actin Cables.

    Directory of Open Access Journals (Sweden)

    Lishibanya Mohapatra


    Full Text Available Actin cables are linear cytoskeletal structures that serve as tracks for myosin-based intracellular transport of vesicles and organelles in both yeast and mammalian cells. In a yeast cell undergoing budding, cables are in constant dynamic turnover yet some cables grow from the bud neck toward the back of the mother cell until their length roughly equals the diameter of the mother cell. This raises the question: how is the length of these cables controlled? Here we describe a novel molecular mechanism for cable length control inspired by recent experimental observations in cells. This "antenna mechanism" involves three key proteins: formins, which polymerize actin, Smy1 proteins, which bind formins and inhibit actin polymerization, and myosin motors, which deliver Smy1 to formins, leading to a length-dependent actin polymerization rate. We compute the probability distribution of cable lengths as a function of several experimentally tuneable parameters such as the formin-binding affinity of Smy1 and the concentration of myosin motors delivering Smy1. These results provide testable predictions of the antenna mechanism of actin-cable length control.


    Directory of Open Access Journals (Sweden)

    Muhammad Siddique Ansari


    Full Text Available Abstract - Business Organizations and Government unequivocally relies on upon data to deal with their business operations. The most unfavorable impact on association is disappointment of friendship, goodness, trustworthiness, legitimacy and probability of data and administrations. There is an approach to ensure data and to deal with the IT framework's Security inside association. Each time the new innovation is made, it presents some new difficulties for the insurance of information and data. To secure the information and data in association is imperative on the grounds that association nowadays inside and remotely joined with systems of IT frameworks. IT structures are inclined to dissatisfaction and security infringement because of slips and vulnerabilities. These slips and vulnerabilities can be brought on by different variables, for example, quickly creating headway, human slip, poor key particulars, poor movement schedules or censuring the threat. Likewise, framework changes, new deserts and new strikes are a huge piece of the time displayed, which helpers augmented vulnerabilities, disappointments and security infringement all through the IT structure life cycle. The business went to the confirmation that it is essentially difficult to ensure a slip free, risk free and secure IT structure in perspective of the disfigurement of the disavowing security parts, human pass or oversight, and part or supplies frustration. Totally secure IT frameworks don't exist; just those in which the holders may have changing degrees of certainty that security needs of a framework are fulfilled do. The key viewpoints identified with security of data outlining are examined in this paper. From the start, the paper recommends pertinent legitimate structure and their duties including open association obligation, and afterward it returns to present and future time, system limits, structure security in business division. At long last, two key inadequacy markers

  2. Marine litter in submarine canyons of the Bay of Biscay (United States)

    van den Beld, Inge M. J.; Guillaumont, Brigitte; Menot, Lénaïck; Bayle, Christophe; Arnaud-Haond, Sophie; Bourillet, Jean-François


    Marine litter is a matter of increasing concern worldwide, from shallow seas to the open ocean and from beaches to the deep-seafloor. Indeed, the deep sea may be the ultimate repository of a large proportion of litter in the ocean. We used footage acquired with a Remotely Operated Vehicle (ROV) and a towed camera to investigate the distribution and composition of litter in the submarine canyons of the Bay of Biscay. This bay contains many submarine canyons housing Vulnerable Marine Ecosystems (VMEs) such as scleractinian coral habitats. VMEs are considered to be important for fish and they increase the local biodiversity. The objectives of the study were to investigate and discuss: (i) litter density, (ii) the principal sources of litter, (iii) the influence of environmental factors on the distribution of litter, and (iv) the impact of litter on benthic communities. Litter was found in all 15 canyons and at three sites on the edge of the continental shelf/canyon, in 25 of 29 dives. The Belle-île and Arcachon Canyons contained the largest amounts of litter, up to 12.6 and 9.5 items per 100 images respectively. Plastic items were the most abundant (42%), followed by fishing-related items (16%). The litter had both a maritime and a terrestrial origin. The main sources could be linked to fishing activities, major shipping lanes and river discharges. Litter appeared to accumulate at water depths of 801-1100 m and 1401-1700 m. In the deeper of these two depth ranges, litter accumulated on a geologically structured area, accounting for its high frequency at this depth. A larger number of images taken in areas of coral in the shallower of these two depth ranges may account for the high frequency of litter detection at this depth. A larger number of litter items, including plastic objects in particular, were observed on geological structures and in coral areas than on areas of bare substratum. The distribution of fishing-related items was similar for the various types of

  3. Particle sedimentation and diffusive convection in submarine clouds (United States)

    Carazzo, G.; Jellinek, M.; Turchyn, A. V.


    The longevity of submarine plumes generated by the release of hydrothermal fluids during crustal rupturing or by the rapid cooling of an erupting lava flow constrains the input of crustal-derived elements into the deep-ocean. Decades of observations of episodic "event plumes" suggest that a key process governing the dynamics of a submarine cloud spreading out laterally from a buoyant rising plume is the production of internal layering. Here, we use geological data on submarine clouds and a new experimental apparatus producing at laboratory scale turbulent, hot particle-laden plumes and clouds to show that this layering occurs where particle diffusive convection driven by the differential diffusion of heat and small mineral precipitates gives rise to a large scale double diffusive instability. We show that this "particle diffusive convection" can extend the longevity of an event plume to two years after its emplacement, allowing iron-sulfide minerals to dissolve and deliver iron to the deep-ocean. The very long residence time imposed by diffusive convective effects does not allow iron-oxide minerals to dissolve but may lead to the formation of iron-rich sediments at large distances from the point of emission. We develop a new theoretical model that includes both sedimentation and dissolution processes to quantify the potential amount of iron produced by the dissolution of iron-sulfide minerals settling through the cloud by diffusive convection. A key prediction is that hydrothermal systems could provide 75% of the global budget of dissolved iron in the deep-ocean. The consideration of scale-basin variations suggests that the Southern Hemisphere is probably the most impacted by hydrothermal iron, consistent with observations and global ocean models. Photographs showing the typical evolution of a lab-scale turbulent, hot particle-laden plume. At stage 1, the buoyant plume reaches a level of neutral buoyancy and spreads out laterally forming a neutrally buoyant cloud

  4. Hawaiian submarine manganese-iron oxide crusts - A dating tool? (United States)

    Moore, J.G.; Clague, D.A.


    Black manganese-iron oxide crusts form on most exposed rock on the ocean floor. Such crusts are well developed on the steep lava slopes of the Hawaiian Ridge and have been sampled during dredging and submersible dives. The crusts also occur on fragments detached from bedrock by mass wasting, on submerged coral reefs, and on poorly lithified sedimentary rocks. The thickness of the crusts was measured on samples collected since 1965 on the Hawaiian Ridge from 140 dive or dredge localities. Fifty-nine (42%) of the sites were collected in 2001 by remotely operated vehicles (ROVs). The thinner crusts on many samples apparently result from post-depositional breakage, landsliding, and intermittent burial of outcrops by sediment. The maximum crust thickness was selected from each dredge or dive site to best represent crusts on the original rock surface at that site. The measurements show an irregular progressive thickening of the crusts toward the northwest-i.e., progressive thickening toward the older volcanic features with increasing distance from the Hawaiian hotspot. Comparison of the maximum crust thickness with radiometric ages of related subaerial features supports previous studies that indicate a crust-growth rate of about 2.5 mm/m.y. The thickness information not only allows a comparison of the relative exposure ages of two or more features offshore from different volcanoes, but also provides specific age estimates of volcanic and landslide deposits. The data indicate that some of the landslide blocks within the south Kona landslide are the oldest exposed rock on Mauna Loa, Kilauea, or Loihi volcanoes. Crusts on the floors of submarine canyons off Kohala and East Molokai volcanoes indicate that these canyons are no longer serving as channelways for downslope, sediment-laden currents. Mahukona volcano was approximately synchronous with Hilo Ridge, both being younger than Hana Ridge. The Nuuanu landslide is considerably older than the Wailau landslide. The Waianae

  5. Newly recognized submarine slide complexes in the southern California Bight (United States)

    Conrad, J. E.; Lee, H. J.; Edwards, B. D.; McGann, M.; Sliter, R. W.


    New high-resolution bathymetric and seismic-reflection surveys have imaged large (7) individual overlapping slides along the western margin of Santa Cruz Basin (SCB slide); 2) a series of slumps and slide scars on the slope south of San Pedro shelf (SPS slide); and 3) a slope failure along the shelf edge in northern San Diego County, termed the Del Mar slide. The SCB slide complex extends for 30 km along the western slope of Santa Cruz Basin, with debris lobes extending 5-8 km into the basin. Head scarps of some of these slides are 50-75 m high. The SPS slide complex also appears to consist of multiple slides, which roughly parallel the Palos Verdes Fault and the San Gabriel Canyon submarine channel on the shelf edge and slope south of San Pedro shelf. Slide deposits associated with this complex are only partially mapped due to limited high-resolution bathymetric coverage, but extend to the south in the area SW of Lasuen Knoll. Seismic-reflection profiles show that some of these deposits are up to 20 m thick. The Del Mar slide is located about 10 km north of La Jolla Canyon and extends about 6 km along the shelf edge. The head scarp lies along the trend of a branch of the Rose Canyon Fault Zone. Radiocarbon ages of sediment overlying this slide indicate the Del Mar slide is approximately 12-16 ka. These large slide complexes have several characteristics in common. Nearly all occur in areas of tectonic uplift. All of the complexes show evidence of recurrent slide activity, exhibiting multiple headwall scarps and debris lobes, and where available, high-resolution seismic-reflection profiles of these slide areas provide evidence of older, buried mass transport deposits. Assuming typical sedimentation rates, the recurrence interval of major slide events appears to be on the order of tens of thousands of years. Most of the slide complexes do not appear to be located in areas of high sediment input. The SCB and Del Mar slides are in areas receiving relatively small

  6. Security affects us all!

    CERN Multimedia

    SMB Department


    In the hope of minimising the number of thefts of the Organization’s property, which can lead to months of work going to waste on certain projects, you are reminded of the importance that CERN attaches to the rules concerning the protection of equipment for which we are responsible. If you see any unusual behaviour or if you are the victim of a theft, don’t hesitate to report it by submitting a ticket through the CERN Portal or calling the CSA. Security affects us all!   CERN is attractive in more ways than one, and it remains as attractive as ever to thieves. With the nice weather and with the holiday season in full swing, the number of thefts recorded at CERN is on the rise. Items stolen include money, computers, electronic equipment, cable drums and copper antennae.   There are a few basic precautions that you should take to protect both your own and the Organization’s property: lock your door, don’t leave valuable items in your office, st...

  7. Current distribution in Cable-In-Conduit Conductors

    Energy Technology Data Exchange (ETDEWEB)

    Ferri, M.A.


    A numerical study of the current distribution in Cable-In-Conduit Conductors (CICC`s) experiencing linearly ramping transport currents and transverse magnetic fields was conducted for both infinitely long, periodic cables and finite length cables terminated in low resistance joints. The goal of the study was to gain insight into the phenomenon known as Ramp Rate Limitation, an as yet unexplained correspondence between maximum attainable current and the ramp time taken to reach that current in CICC superconducting magnets. A discrete geometric model of a 27 strand multiply twisted CICC was developed to effectively represent the flux linkages, mutual inductances, and resistive contact points between the strands of an experimentally tested cable. The results of the numerical study showed that for fully periodic cables, the current imbalances due to ramping magnetic fields and ramping transport currents are negligible in the range of experimentally explored operating conditions. For finite length, joint terminated cables, however, significant imbalances can exist. Unfortunately, quantitative results are limited by a lack of knowledge of the transverse resistance between strands in the joints. Nonetheless, general results are presented showing the dependency of the imbalance on cable length, ramp time, and joint resistance for both ramping transverse magnet fields and ramping transport currents. At the conclusion of the study, it is suggested that calculated current imbalances in a finite length cable could cause certain strands to prematurely ``quench`` -- become non-superconducting --thus leading to an instability for the entire cable. This numerically predicted ``current imbalance instability`` is compared to the experimentally observed Ramp Rate Limitation for the 27 strand CICC sample.

  8. Strategic information security

    CERN Document Server

    Wylder, John


    Introduction to Strategic Information SecurityWhat Does It Mean to Be Strategic? Information Security Defined The Security Professional's View of Information Security The Business View of Information SecurityChanges Affecting Business and Risk Management Strategic Security Strategic Security or Security Strategy?Monitoring and MeasurementMoving Forward ORGANIZATIONAL ISSUESThe Life Cycles of Security ManagersIntroductionThe Information Security Manager's Responsibilities The Evolution of Data Security to Information SecurityThe Repository Concept Changing Job Requirements Business Life Cycles

  9. Low AC Loss in a 3 kA HTS Cable of the Dutch Project

    NARCIS (Netherlands)

    Chevtchenko, O.; Zuijderduin, R.; Smit, J.; Willen, D.; Lentge, H.; Thidemann, C.; Traeholt, C.; Melnik, I.; Geschiere, A.


    are: a cable has to fit in an annulus of 160 mm, with two cooling stations at the cable ends only. Existing solutions for HTS cables would lead to excessively high coolant pressure drop in the cable, potentially affecting public acceptance of the project. A way out would be to substantially reduce


    Directory of Open Access Journals (Sweden)

    T.Yu. Antonets


    Full Text Available In this paper, experiment for determining the temperature difference between the elements of cable and in the open air is considered. The formation of a three cables laid in a plane with different spacing between adjacent cables. Tests to heat of cables for XLPE-polyethylene are used as a solid dielectric insulation. The line to XLPE-cables in group running horizontally, provided that the cables are of equal diameter and emit equal losses. It is limited to the following: the air flow around the cables may be necessary restricted by proximity to next cables. When single-core cables are installed in parallel the load current may not share equally between the parallel cables. This is because a significant proportion of the impedance of large conductors is due to self reactance and mutual reactance. Hence the spacing and relative location of each cable will have an effect on the current sharing. Calculation for each cable configuration is necessary. Possibility of using for determining the thermal properties of XLPE-cables a sheath applied over the cable surface with coefficient convection heat transfer between cable surface and the air region about it of equal zero. The work is devoted to creation of a method for calculation of the current rating of high-voltage cables in conditions function.

  11. 47 CFR 76.611 - Cable television basic signal leakage performance criteria. (United States)


    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Cable television basic signal leakage...) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.611 Cable television basic signal leakage performance criteria. (a) No cable television system shall commence or...

  12. Numerical Modeling of Physic-Chemical Processes of Multicore Cable in the Polymerization

    Directory of Open Access Journals (Sweden)

    Abramova A.V.


    Full Text Available There are developed mathematical model of physical and chemical processes of polymerization adhesive coating stranded cable. There are found time of full polymerization in the shell of the multicore cable product. There are compared with the single-core cable. Also the necessity of changing the speed of the cable pulling the multilayer product compared with single-core.

  13. 47 CFR 76.905 - Standards for identification of cable systems subject to effective competition. (United States)


    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Standards for identification of cable systems... Regulation § 76.905 Standards for identification of cable systems subject to effective competition. (a) Only the rates of cable systems that are not subject to effective competition may be regulated. (b) A cable...

  14. Comparison of several innovative bridge cable surface modifications

    DEFF Research Database (Denmark)

    Kleissl, Kenneth; Georgakis, Christos T.

    Over the last two decades, several bridge cable manufacturers have introduced surface modifications on the high-density polyethylene (HDPE) sheathing that is installed for the protection of inner cable strands or wires. The modifications are based on research undertaken predominantly in Europe...... and Japan, with two different prevailing systems: HDPE tubing fitted with helical fillets and tubing with pattern-indented surfaces. In the US and Europe, helical fillets dominate, whilst pattern indented sur-faces are more common in Asia, particularly for long-span cable-stayed bridges. Research...

  15. Cable fire risk of a nuclear power plant; Ydinvoimalaitoksen kaapelipaloriski

    Energy Technology Data Exchange (ETDEWEB)

    Aulamo, H.


    The aim of the study is to carry out a comprehensive review of cable fire risk issues of nuclear power plants (NPP) taking into account latest fire and risk assessment research results. A special emphasis is put on considering the fire risk analysis of cable rooms in the framework of TVO Olkiluoto NPP probabilistic safety assessment. The assumptions made in the analysis are assessed. The literature study section considers significant fire events at nuclear power plants, the most severe of which have nearly led to a reactor core damage (Browns Ferry, Greifswald, Armenia, Belojarsk, Narora). Cable fire research results are also examined. 62 refs.

  16. High-Density Optical Cable For Public Communications (United States)

    Trunk, Jonas; Monteiro, Ricardo


    Optical fiber networks for public communications are moving toward the subscribers and therefore feeder optical cables with relative great amount of fibers are needed. A 120 fibers cable has been designed with ten UV curable acrilate coated fibers accommodate together inside each plastic loose tube, and twelve these tubes are stranded around a central strength member resulting in a high packaging density construction. A cable prototipe has been manufactured and some tests was made under conditions which simulate the situations found during installation and after due to hostile environments.

  17. Arc tracking energy balance for copper and aluminum aeronautic cables (United States)

    André, T.; Valensi, F.; Teulet, P.; Cressault, Y.; Zink, T.; Caussé, R.


    Arc tracking tests have been carried out between two voluntarily damaged aeronautic cables. Copper or aluminum conductors have been exposed to short circuits under alternating current. Various data have been recorded (arc voltage and current, radiated power and ablated mass), enabling to determine a power balance, in which every contribution is estimated. The total power is mainly transferred to the cables (between 50 and 65%, depending on the current and the cable type), and causes the melting and partial vaporization of the metallic core and insulating material, or is conducted or radiated. The other part is deposited into the arc column, being either radiated, convected or conducted.

  18. Cable Damage Detection System and Algorithms Using Time Domain Reflectometry

    Energy Technology Data Exchange (ETDEWEB)

    Clark, G A; Robbins, C L; Wade, K A; Souza, P R


    This report describes the hardware system and the set of algorithms we have developed for detecting damage in cables for the Advanced Development and Process Technologies (ADAPT) Program. This program is part of the W80 Life Extension Program (LEP). The system could be generalized for application to other systems in the future. Critical cables can undergo various types of damage (e.g. short circuits, open circuits, punctures, compression) that manifest as changes in the dielectric/impedance properties of the cables. For our specific problem, only one end of the cable is accessible, and no exemplars of actual damage are available. This work addresses the detection of dielectric/impedance anomalies in transient time domain reflectometry (TDR) measurements on the cables. The approach is to interrogate the cable using time domain reflectometry (TDR) techniques, in which a known pulse is inserted into the cable, and reflections from the cable are measured. The key operating principle is that any important cable damage will manifest itself as an electrical impedance discontinuity that can be measured in the TDR response signal. Machine learning classification algorithms are effectively eliminated from consideration, because only a small number of cables is available for testing; so a sufficient sample size is not attainable. Nonetheless, a key requirement is to achieve very high probability of detection and very low probability of false alarm. The approach is to compare TDR signals from possibly damaged cables to signals or an empirical model derived from reference cables that are known to be undamaged. This requires that the TDR signals are reasonably repeatable from test to test on the same cable, and from cable to cable. Empirical studies show that the repeatability issue is the 'long pole in the tent' for damage detection, because it is has been difficult to achieve reasonable repeatability. This one factor dominated the project. The two-step model

  19. Cubierta de doble curvatura de cables pretensados (Finlandia

    Directory of Open Access Journals (Sweden)

    Bergholt, K.


    Full Text Available A new ice hockey stadium has been built in Tampere, Finland. It has a reinforced concrete structure and a light, double curvature, roof suspended from a network of prestressed cables. It has a rectangular planform, 63x92 m, and it can accommodate 10,000 spectators. The hockey rink is in the centre. After a brief comparison of various types of suspended roofs, the author describes his own design, and discusses the most delicate aspects of the project. The cables are anchored in lateral arched beams, whose stability is provided by external prestressed concrete ribs. The author emphasizes the importance of these beams for the overall efficiency of the project. Special care was taken to avoid curvature of the cables where these penetrate into the lateral beams, without, however, restricting the freedom of the cables to oscillate. The article describes the placing of the cables, the details of the cables themselves, and their stretching: all of which is a technology that is now well know and tried.El nuevo estadio para hockey sobre hielo, construido, en Tampere, Finlandia, a base de una estructura en hormigón armado y una cubierta ligera de doble curvatura formada por una red de cables pretensados, tiene forma rectangular con planta de 63,2 x 92 m; está previsto para 10.000 espectadores y lleva en el centro la cancha para hockey. Después de una ligera comparación de los distintos tipos de cubiertas suspendidas, el autor describe su obra y analiza las partes más sensibles de la cubierta suspendida por él proyectada. Los cables están anclados en vigas o arcos laterales cuya estabilidad está asegurada por tirantes exteriores de hormigón pretensado. El autor subraya la particular importancia que tiene la concepción de estas vigas o arcos laterales para la economía de la obra. Se tuvo especial cuidado en evitar codos en los cables donde éstos entran en las vigas o arcos laterales, sin por eso restringa la necesaria libertad de movimiento de

  20. Sediment Biogeochemistry After the Entrance of Cable Bacteria

    DEFF Research Database (Denmark)

    Risgaard-Petersen, Nils

    , sulfide-rich coastal sediments, salt marshes seasonally hypoxic basins, subtidal coastal mud plains, as well as freshwater sediments and waterlogged soils. In this talk I will review our current knowledge on how cable bacteria influence the biogeochemistry of sediments. The cable bacteria form electric...... and the formation of sulfate[3] Field studies conducted in the marine environment indicate that some of these effects are expressed in a way that marine systems with active cable bacteria populations have elevated phosphorus-retention{Sulu-Gambari, 2016 #1501} and acts as strong buffers against adverse stage...

  1. Simultaneous Thermal and Gamma Radiation Aging of Cable Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Fifield, Leonard S.; Liu, Shuaishuai; Bowler, Nicola


    Polymers used in nuclear power plant electrical cable systems experience aging and degradation over time due to environmental stress including heat and gamma irradiation. Prediction of long-term cable performance has been based on results of short-term accelerated laboratory aging studies, but questions remain regarding the correlation of accelerated aging to long-term, in-plant aging. This work seeks to increase understanding of the combined effects of heat and radiation on cable polymer material aging toward addressing these questions.

  2. Fiber Optic Cable Thermal Preparation to Ensure Stable Operation (United States)

    Thoames Jr, William J.; Chuska, Rick F.; LaRocca, Frank V.; Switzer, Robert C.; Macmurphy, Shawn L.; Ott, Melanie N.


    Fiber optic cables are widely used in modern systems that must provide stable operation during exposure to changing environmental conditions. For example, a fiber optic cable on a satellite may have to reliably function over a temperature range of -50 C up to 125 C. While the system requirements for a particular application will dictate the exact method by which the fibers should be prepared, this work will examine multiple ruggedized fibers prepared in different fashions and subjected to thermal qualification testing. The data show that if properly conditioned the fiber cables can provide stable operation, but if done incorrectly, they will have large fluctuations in transmission.

  3. A preliminary bending fatigue spectrum for steel monostrand cables

    DEFF Research Database (Denmark)

    Winkler, Jan; Fischer, Gregor; Georgakis, Christos T.


    This paper presents the results of the experimental study on the bending fatigue resistance of high-strength steel monostrand cables. From the conducted fatigue tests in the high-stress, low-cycle region, a preliminary bending fatigue spectrum is derived for the estimation of monostrand cable...... service life expectancy. The presented preliminary bending fatigue spectrum of high-strength monostrands is currently unavailable in the published literature. The presented results provide relevant information on the bending mechanism and fatigue characteristics of monostrand steel cables in tension...

  4. Security Bingo

    CERN Multimedia

    Computer Security Team


    Want to check your security awareness and win one of three marvellous books on computer security? Just print out this page, mark which of the 25 good practices below you already follow, and send the sheet back to us by 31 October 2011 at either or P.O. Box G19710.   Winners[1] must show that they fulfil at least five good practices in a continuous vertical, horizontal or diagonal row. For details on CERN Computer Security, please consult I personally…   …am concerned about computer security. …run my computer with an anti-virus software and up-to-date signature files. …lock my computer screen whenever I leave my office. …have chosen a reasonably complex password. …have restricted access to all my files and data. …am aware of the security risks and threats to CERN’s computing facilities. &hell...

  5. Aerodynamic instability of cables in transmission power lines; Inestabilidad aerodinamica en cables de lineas de transmision

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Lopez, Alberto; Vilar Rojas, Jorge Ivan; Munoz Black, Celso J. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)


    One of the aerodynamic instabilities of transmission power lines cables is galloping, which consists in the appearance of important cable vibrations, mainly when the wind hits orthogonally the power line. In some cases the maximum amplitude that occurs reaches several meters, even when the wind velocities in a region are well below the value used for the mechanical design of the power lines. In general terms, galloping is associated with particular climatic conditions such as low temperatures and high humidities. In these conditions a coating of ice that adheres to the cable is formed, changing its transverse cross section, propitiating the galloping, although some authors have reported galloping without ice. These climatic conditions are presented mainly in the Northern part of our country and in the high regions of the mountain zones; nevertheless, the galloping phenomenon has been reported in few cases by Comision Federal de Electricidad (CFE). The possible expansion of the power lines in these regions of the country leads to prevent the measures needed to diminish the appearance of this phenomenon. In this paper mention is made in particular of the solution adopted to the galloping problem that has appeared in the transmission power line of Salamayuca to Reforma, Ciudad Juarez, Chihuahua (CFE,1991). [Espanol] Una de las inestabilidades aerodinamicas que se presentan en los cables de lineas de transmision es el galopeo, el cual consiste en la aparicion de vibraciones importantes de los cables, sobre todo cuando el flujo del viento incide ortogonalmente a la linea. En algunos casos las amplitudes maximas que se presentan llegan a ser de varios metros, aun cuando las velocidades del viento en una region esten muy por debajo del valor empleado para el diseno mecanico de las lineas. Generalmente, el galopeo se asocia con condiciones climaticas particulares como son las bajas temperaturas y altas humedades. En estas condiciones se forma una cubierta de hielo que se

  6. Multi-scale evaluations of submarine groundwater discharge

    Directory of Open Access Journals (Sweden)

    M. Taniguchi


    Full Text Available Multi-scale evaluations of submarine groundwater discharge (SGD have been made in Saijo, Ehime Prefecture, Shikoku Island, Japan, by using seepage meters for point scale, 222Rn tracer for point and coastal scales, and a numerical groundwater model (SEAWAT for coastal and basin scales. Daily basis temporal changes in SGD are evaluated by continuous seepage meter and 222Rn mooring measurements, and depend on sea level changes. Spatial evaluations of SGD were also made by 222Rn along the coast in July 2010 and November 2011. The area with larger 222Rn concentration during both seasons agreed well with the area with larger SGD calculated by 3D groundwater numerical simulations.

  7. Impact of Cross-Tie Properties on the Modal Behavior of Cable Networks on Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Javaid Ahmad


    Full Text Available Dynamic behaviour of cable networks is highly dependent on the installation location, stiffness, and damping of cross-ties. Thus, these are the important design parameters for a cable network. While the effects of the former two on the network response have been investigated to some extent in the past, the impact of cross-tie damping has rarely been addressed. To comprehend our knowledge of mechanics associated with cable networks, in the current study, an analytical model of a cable network will be proposed by taking into account both cross-tie stiffness and damping. In addition, the damping property of main cables in the network will also be considered in the formulation. This would allow exploring not only the effectiveness of a cross-tie design on enhancing the in-plane stiffness of a constituted cable network, but also its energy dissipation capacity. The proposed analytical model will be applied to networks with different configurations. The influence of cross-tie stiffness and damping on the modal response of various types of networks will be investigated by using the corresponding undamped rigid cross-tie network as a reference base. Results will provide valuable information on the selection of cross-tie properties to achieve more effective cable vibration control.

  8. Impact of Cross-Tie Properties on the Modal Behavior of Cable Networks on Cable-Stayed Bridges. (United States)

    Ahmad, Javaid; Cheng, Shaohong; Ghrib, Faouzi


    Dynamic behaviour of cable networks is highly dependent on the installation location, stiffness, and damping of cross-ties. Thus, these are the important design parameters for a cable network. While the effects of the former two on the network response have been investigated to some extent in the past, the impact of cross-tie damping has rarely been addressed. To comprehend our knowledge of mechanics associated with cable networks, in the current study, an analytical model of a cable network will be proposed by taking into account both cross-tie stiffness and damping. In addition, the damping property of main cables in the network will also be considered in the formulation. This would allow exploring not only the effectiveness of a cross-tie design on enhancing the in-plane stiffness of a constituted cable network, but also its energy dissipation capacity. The proposed analytical model will be applied to networks with different configurations. The influence of cross-tie stiffness and damping on the modal response of various types of networks will be investigated by using the corresponding undamped rigid cross-tie network as a reference base. Results will provide valuable information on the selection of cross-tie properties to achieve more effective cable vibration control.

  9. Simple Program to Investigate Hysteresis Damping Effect of Cross-Ties on Cables Vibration of Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Panagis G. Papadopoulos


    Full Text Available A short computer program, fully documented, is presented, for the step-by-step dynamic analysis of isolated cables or couples of parallel cables of a cable-stayed bridge, connected to each other and possibly with the deck of the bridge, by very thin pretensioned wires (cross-ties and subjected to variation of their axial forces due to traffic or to successive pulses of a wind drag force. A simplified SDOF model, approximating the fundamental vibration mode, is adopted for every individual cable. The geometric nonlinearity of the cables is taken into account by their geometric stiffness, whereas the material nonlinearities of the cross-ties include compressive loosening, tensile yielding, and hysteresis stress-strain loops. Seven numerical experiments are performed. Based on them, it is observed that if two interconnected parallel cables have different dynamic characteristics, for example different lengths, thus different masses, weights, and geometric stiffnesses, too, or if one of them has a small additional mass, then a single pretensioned very thin wire, connecting them to each other and possibly with the deck of the bridge, proves effective in suppressing, by its hysteresis damping, the vibrations of the cables.

  10. Junos Security

    CERN Document Server

    Cameron, Rob; Giecco, Patricio; Eberhard, Timothy; Quinn, James


    Junos® Security is the complete and authorized introduction to the new Juniper Networks SRX hardware series. This book not only provides a practical, hands-on field guide to deploying, configuring, and operating SRX, it also serves as a reference to help you prepare for any of the Junos Security Certification examinations offered by Juniper Networks. Network administrators and security professionals will learn how to use SRX Junos services gateways to address an array of enterprise data network requirements -- including IP routing, intrusion detection, attack mitigation, unified threat manag

  11. Secure PVM

    Energy Technology Data Exchange (ETDEWEB)

    Dunigan, T.H.; Venugopal, N.


    This research investigates techniques for providing privacy, authentication, and data integrity to PVM (Parallel Virtual Machine). PVM is extended to provide secure message passing with no changes to the user`s PVM application, or, optionally, security can be provided on a message-by message basis. Diffe-Hellman is used for key distribution of a single session key for n-party communication. Keyed MD5 is used for message authentication, and the user may select from various secret-key encryption algorithms for message privacy. The modifications to PVM are described, and the performance of secure PVM is evaluated.

  12. Computer security

    CERN Document Server

    Gollmann, Dieter


    A completely up-to-date resource on computer security Assuming no previous experience in the field of computer security, this must-have book walks you through the many essential aspects of this vast topic, from the newest advances in software and technology to the most recent information on Web applications security. This new edition includes sections on Windows NT, CORBA, and Java and discusses cross-site scripting and JavaScript hacking as well as SQL injection. Serving as a helpful introduction, this self-study guide is a wonderful starting point for examining the variety of competing sec

  13. SC Power leads and cables - Nominal Current Test Performance of 2 kA-Class High-Tc Superconducting Cable Conductors and Its Implications for Cooling Systems for Utility Cables

    DEFF Research Database (Denmark)

    Willen, D. W. A; Daumling, M.; Rasmussen, C. N.


    configurations. The conductors are characterised under dc and ac conditions. The current and voltage is recorded during the tests in order to determine the impedances and the losses of the cable models. Using a phase-sensitive measurement with two lock-in amplifiers, small losses can be accurately measured...... individual layers in the cables saturate. The loss-contributions from other components of the cable system are discussed,and the implications for the cooling apparatus for superconducting utility cables are determined....

  14. Perimitrax: the next generation in guided radar perimeter security technology (United States)

    Maki, Melvin C.; Hill, Charles R.


    The first application of 'leaky' or 'ported' coaxial cables to radar system for covert detection of human intruders for outdoor perimeter security was in the early 1970's. Early systems were relatively rudimentary using large central processors and difficult to manufacture sensing cables. However, since that time these systems have evolved in both design and performance and been proven to have both high detection performance and low false and nuisance response in such diverse, all-weather perimeter applications as military bases, corrections, and industrial sites. This paper introduces the latest generation of guided radar security technology now being fielded. This generation features more flexible and modular 'plug and play' electronics, matched to both large and small installations from the sensor zone end, up to the control and display. Advanced signal processing is now included which is tuned to discriminate the unique features of the intruder from those of the environment. Such processing capitalize on the ability to look at and classify features of larger perimeters. New 'TR' technology sensor cables have ben developed which are manufactured in a single pass approach to provide more uniformity of sensor performance. These sensor include both a siamese design for single slot burial, and also a small diameter dual cable for wider zone requirements. This paper will outline the major elements of guided radar sensors and overview the new components and architecture of this latest generation. It will discuss the results of early operational performance testing, and the new benefits for diverse applications from government, to corrections and airports.

  15. Risk assessment in submarine outfall projects: the case of Portugal. (United States)

    Mendonça, Ana; Losada, Miguel Ángel; Reis, Maria Teresa; Neves, Maria Graça


    Submarine outfalls need to be evaluated as part of an integrated environmental protection system for coastal areas. Although outfalls are tight with the diversity of economic activities along a densely populated coastline being effluent treatment and effluent reuse a sign of economic prosperity, precautions must be taken in the construction of these structures. They must be designed so as to have the least possible impact on the environment and at the same time be economically viable. This paper outlines the initial phases of a risk assessment procedure for submarine outfall projects. This approach includes a cost-benefit analysis in which risks are systematically minimized or eliminated. The methods used in this study also allow for randomness and uncertainty. The input for the analysis is a wide range of information and data concerning the failure probability of outfalls and the consequences of an operational stoppage or failure. As part of this risk assessment, target design levels of reliability, functionality, and operationality were defined for the outfalls. These levels were based on an inventory of risks associated with such construction projects, and thus afforded the possibility of identifying possible failure modes. This assessment procedure was then applied to four case studies in Portugal. The results obtained were the values concerning the useful life of the outfalls at the four sites and their joint probability of failure against the principal failure modes assigned to ultimate and serviceability limit states. Also defined were the minimum operationality of these outfalls, the average number of admissible technical breakdowns, and the maximum allowed duration of a stoppage mode. It was found that these values were in consonance with the nature of the effluent (tourist-related, industrial, or mixed) as well as its importance for the local economy. Even more important, this risk assessment procedure was able to measure the impact of the outfalls on

  16. Imaging deformation in submarine thrust belts using seismic attributes (United States)

    Iacopini, David; Butler, Robert W. H.


    Uncertainty exists as to the patterns of deformation that develop within submarine thrust belts. This case study uses a large-scale gravity-driven fold-thrust structure as an analogue for submarine fold thrust systems in general. Seismic attribute analysis and mapping provide ways of identifying complex fault patterns and associated deformation that are otherwise unresolved in conventional amplitude displays. These methods are developed and applied to a 3D dataset and used to investigate the geometry, internal architecture and the nature of the low signal/noise incoherency and discontinuities observed on the km-scale. Semblance (coherency), curvatures and spectral decomposition were all computed and used as attributes. Collectively these define volumes within the seismic data where the signal is greatly reduced — features termed here "disturbance geobodies". The study shows that thrust faults that, on conventional amplitude displays appear to be simple and continuous, are likely to consist of complex arrays of anastamosing fault strands. Adjacent to these composite fault zones are greater volumes of deformed rocks (disturbance geobodies) across which there are only minor stratal offsets. Similarly volumes of high stratal curvature coincide with disturbance geobodies, again interpreted as zones of weak, distributed deformation. These relationships between narrow thrust faults and broader zones of deformation are broadly comparable to those observed in outcrops within exhumed thrust systems. Application of the seismic imaging techniques developed here will improve the understanding of the localization of deformation in sedimentary successions with important implications for predicting fluid flow within other deep water structures such as subduction accretion complexes.

  17. Geo-hazard by sediment mass movements in submarine canyons (United States)

    Ghaith, Afif; Fakhri, Milad; Ivaldi, Roberta; Ciavola, Paolo


    Submarine mass movements and their consequences are of major concern for coastal communities and infrastructures but also for the exploitation and the development of seafloor resources. Elevated awareness of the need for better understanding of the underwater mass movement is coupled with great advances in underwater mapping technologies over the past two decades. The seafloor in the Nahr Ibrahim and Saida regions (Lebanon) is characterized by deep canyons, reaching one thousand meters depths in proximity of the coast. Signs of submarine mass movement instability related to these canyons create a connection between shallow and deep water. The presence of these canyons in a tectonically active area generates a particular drained mechanism to the sediment in form of mass movement and slumping. Identification of potential areas where slope movements could be triggered requires data with high spatial resolution. Since this area is poorly explored, in the framework of an international project between Lebanese Navy, Lebanese National Center for Marine Sciences, University of Ferrara and Italian Hydrographic Institute, we analyse the morpho-bathymetric and sedimentological characters of the coastal and shelf sectors. Multibeam echosounder and sub-bottom profiler acoustic systems calibrated with ground truths (sediment grab and core samples) allow us to characterize the nature of seafloor and sub-seafloor with particular detail to the geotechnical properties of sediments and high resolution seismic stratigraphy of the shallow layers. The detection of particular undersea features provides detail maps which are in support to littoral morpho-dynamics, coastal transport and sediment budget. Multilayer hydro-oceanographic map, referring to the seafloor dynamics in connection with deep water environment and drainage system, in accordance to the International Hydrographic Standards and nautical supports, are produced. This high resolution multibeam bathymetry dataset, integrated

  18. Environmental impacts of cable connections of offshore wind power parks at the electric power network. Impacts of operational electrical and magnetic fields; Umweltauswirkungen der Kabelanbindung von Offshore-Windenergieparks an das Verbundstromnetz. Effekte betriebsbedingter elektrischer und magnetischer Felder sowie thermischer Energieeintraege in den Meeresgrund

    Energy Technology Data Exchange (ETDEWEB)

    Pophof, Blanka; Geschwentner, Dirk


    According to the offshore network development plan from August 2012, the Federal Maritime and Hydrographic Agency (Hamburg, Federal Republic of Germany) is responsible for a strategic environmental impact assessment of offshore wind power plants. The contribution under consideration deals exclusively with electrical and magnetic fields emitted by submarine cables in operation as well as with the possible impacts of electrical and magnetic fields on marine organisms and the general population. Some marine organisms may perceive electrical fields and orientate themselves by magnetic fields. Changes in behaviour of marine organisms are possible. Thermal impacts may result in sedimentary changes. The consequences of these changes are assessable only partly at present.

  19. Did a "lucky shot" sink the submarine H.L. Hunley? (United States)

    Lance, Rachel M; Warder, Henry; Bass, Cameron R Dale


    The H.L. Hunley was the first submarine to be successful in combat, sinking the Union vessel Housatonic outside Charleston Harbor in 1864 during the Civil War. However, despite marking a milestone in military history, little is known about this vessel or why it sank. One popular theory is the "lucky shot" theory: the hypothesis that small arms fire from the crew of the Housatonic may have sufficiently damaged the submarine to sink it. However, ballistic experiments with cast iron samples, analysis of historical experiments firing Civil War-era projectiles at cast iron samples, and calculation of the tidal currents and sinking trajectory of the submarine indicate that this theory is not likely. Based on our results, the "lucky shot" theory does not explain the sinking of the world's first successful combat submarine. Published by Elsevier B.V.

  20. The impact of glacier geometry on meltwater plume structure and submarine melt in Greenland fjords

    NARCIS (Netherlands)

    Carroll, D.; Sutherland, D. A.; Hudson, B.; Moon, T.; Catania, G. A.; Shroyer, E. L.; Nash, J. D.; Bartholomaus, T. C.; Felikson, D.; Stearns, L. A.; Noël, B. P Y; van den Broeke, M. R.


    Meltwater from the Greenland Ice Sheet often drains subglacially into fjords, driving upwelling plumes at glacier termini. Ocean models and observations of submarine termini suggest that plumes enhance melt and undercutting, leading to calving and potential glacier destabilization. Here we

  1. An Analysis of the Effectiveness of a New Watchstanding Schedule for U.S. Submariners

    National Research Council Canada - National Science Library

    Osborn, Christopher


    A need exists within the U.S. submarine force to employ an operational schedule that provides more sleep and that is in better alignment with human circadian rhythms, thus improving cognitive effectiveness...

  2. Fuel cell systems for submarines: from the first idea to serial production (United States)

    Psoma, Angela; Sattler, Gunter

    The future submarines of Howaldtswerke-Deutsche Werft AG (HDW) will be equipped with fuel cell power plants for air independent propulsion. In the 1970s the decision for a fuel cell system on submarines was made. Tests in the 1980s confirmed the feasibility of fuel cells on submarines. Positive development results in the 1990s led to series production of fuel cell equipped submarines, which will be in operation from 2003 onwards. Strictly controlled development work was necessary to reach the goal of series production. The train of thought behind this process of development is described in this paper starting with the initial idea and ending with the description of the serial production of the fuel cell power plant. The future outlook gives an impression of current development work.

  3. Submarine Warfare in the 20th & 21st Centuries: A Bibliography

    National Research Council Canada - National Science Library

    Huygen, Michaele


    There are constant motions in the sea caused by atmospheric and seabed activities volcanic disruptions marine animals ships and submarines -- all of which create what is called the ambient noise level of the oceans...

  4. The risk of hydrogen explosion in a submarine p. IV The implementation of high risk projects

    Directory of Open Access Journals (Sweden)

    Kłos Ryszard


    Full Text Available This series of articles on high risk projects looks at the example of the modernisation of hydrogen incinerators on a submarine. The article describes problems connected with the management of such a project.

  5. A Statistical Analysis of the Impact of Marital Status on Nuclear Submarine Officer Retention

    National Research Council Canada - National Science Library

    Phelps, Matthew


    This thesis develops multivariate logit models to estimate the impact of marital status and the independent effect of dependent children on nuclear submarine officer retention beyond the minimum service requirement (MSR...

  6. Observations of nearshore groundwater discharge: Kahekili Beach Park submarine springs, Maui, Hawaii

    Directory of Open Access Journals (Sweden)

    P.W. Swarzenski


    New hydrological insights for the region: Estimates of submarine groundwater discharge were derived for a primary vent site and surrounding coastal waters off west Maui, Hawaii using an excess 222Rn (t1/2 = 3.8 d mass balance model. Such estimates were complemented with a novel thoron (220Rn, t1/2 = 56 s groundwater discharge tracer application, as well as oceanographic time series and thermal infrared imagery analyses. In combination, this suite of techniques provides new insight into the connectivity of the coastal aquifer with the near-shore ocean and examines the physical drivers of submarine groundwater discharge. Lastly, submarine groundwater discharge derived constituent concentrations were tabulated and compared to surrounding seawater concentrations. Such work has implications for the management of coastal aquifers and downstream nearshore ecosystems that respond to sustained constituent loadings via this submarine route.

  7. Dance With the One That Brought You: Revitalizing Antisubmarine Warfare to Counter Chinese Diesel Submarines

    National Research Council Canada - National Science Library

    Farrell, Richard


    .... Navy needs to revitalize ASW, or risk losing the ability to gain sea control in strategic areas of the East Asian Littoral and South China Sea due to a rising Chinese diesel-electric submarine threat...

  8. Submarine Upward Looking Sonar Ice Draft Profile Data and Statistics, Version 1 (United States)

    National Aeronautics and Space Administration — This data set consists of upward looking sonar sea ice draft data collected by submarines in the Arctic Ocean. It includes data from both U.S. Navy and Royal Navy...

  9. Navy Trident Submarine Conversion (SSGN) Program: Background and Issues for Congress

    National Research Council Canada - National Science Library

    O'Rourke, Ronald


    ...) into cruisemissile- carrying and special operations forces (SOF) support submarines (SSGNs). The total estimated cost of the program, which has been increasing over time, is now $4,018 million...

  10. Secure portal.

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Cynthia Lee


    There is a need in security systems to rapidly and accurately grant access of authorized personnel to a secure facility while denying access to unauthorized personnel. In many cases this role is filled by security personnel, which can be very costly. Systems that can perform this role autonomously without sacrificing accuracy or speed of throughput are very appealing. To address the issue of autonomous facility access through the use of technology, the idea of a ''secure portal'' is introduced. A secure portal is a defined zone where state-of-the-art technology can be implemented to grant secure area access or to allow special privileges for an individual. Biometric technologies are of interest because they are generally more difficult to defeat than technologies such as badge swipe and keypad entry. The biometric technologies selected for this concept were facial and gait recognition. They were chosen since they require less user cooperation than other biometrics such as fingerprint, iris, and hand geometry and because they have the most potential for flexibility in deployment. The secure portal concept could be implemented within the boundaries of an entry area to a facility. As a person is approaching a badge and/or PIN portal, face and gait information can be gathered and processed. The biometric information could be fused for verification against the information that is gathered from the badge. This paper discusses a facial recognition technology that was developed for the purposes of providing high verification probabilities with low false alarm rates, which would be required of an autonomous entry control system. In particular, a 3-D facial recognition approach using Fisher Linear Discriminant Analysis is described. Gait recognition technology, based on Hidden Markov Models has been explored, but those results are not included in this paper. Fusion approaches for combining the results of the biometrics would be the next step in realizing

  11. European Security

    DEFF Research Database (Denmark)

    Møller, Bjørn

    Theoretical chapters on "Security", "Organisations" and "Regions," Historical Chapters on "Europe and Its Distinguishing Features" and on "The United Nations," "NATO," "The CSCE/OSCE and the Council of Europe" and "The European Union"......Theoretical chapters on "Security", "Organisations" and "Regions," Historical Chapters on "Europe and Its Distinguishing Features" and on "The United Nations," "NATO," "The CSCE/OSCE and the Council of Europe" and "The European Union"...

  12. Security Studies




    Security Studies has firmly established itself as a leading journal on international security issues. The journal publishes theoretical, historical and policy-oriented articles on the causes and consequences of war, and the sources and conditions of peace. The journal has published articles on balancing vs. bandwagoning, deterrence in enduring rivalries, the Domino theory, nuclear weapons proliferation, civil-military relations, political reforms in China, strategic culture in Asia and the P...

  13. Secure Directories


    Chadwick, David W.


    This paper describes the mechanisms that are needed in order to provide a secure directory service based on the X.500 data model. A brief introduction to the X.500 data model is given followed by an overview of the Lightweight Directory Access Protocol. Security can be provided by three functions: an application level firewall, an authentication mechanism, and an access control scheme. A description of the X.500 and LDAP access control models is presented followed by the authentication method...

  14. On the stiffness analysis of a cable driven leg exoskeleton. (United States)

    Sanjeevi, N S S; Vashista, Vineet


    Robotic systems are being used for gait rehabilitation of patients with neurological disorder. These devices are externally powered to apply external forces on human limbs to assist the leg motion. Patients while walking with these devices adapt their walking pattern in response to the applied forces. The efficacy of a rehabilitation paradigm thus depends on the human-robot interaction. A cable driven leg exoskeleton (CDLE) use actuated cables to apply external joint torques on human leg. Cables are lightweight and flexible but can only be pulled, thus a CDLE requires redundant cables. Redundancy in CDLE can be utilized to appropriately tune a robot's performance. In this work, we present the stiffness analysis of CDLE. Different stiffness performance indices are established to study the role of system parameters in improving the human-robot interaction.

  15. Wind-induced vibration of stay cables : brief (United States)


    The objectives of this project were to: : Identify gaps in current knowledge base : Conduct analytical and experimental research in critical areas : Study performance of existing cable-stayed bridges : Study current mitigation methods...

  16. Dynamic properties of stay cables on the Penobscot Narrows bridge. (United States)


    Cable-stayed bridges have been recognized as the most efficient and cost effective structural form for medium to long : span bridges over the past several decades. With their widespread use, cases of serviceability problems associated with : large am...

  17. Plastic molds reduce cost of encapsulating electric cable connectors (United States)

    Knott, D.


    Resin casting of the aluminum master pattern forms a plastic mold for encapsulating a cable connector. An elastomer is injected into the mold and cured. The mold is disassembled leaving an elastomeric encapsulation around the connector.

  18. The Electrical Resistance of Rutherford-Type Superconducting Cable Splices

    CERN Document Server

    Heck, C; Fleiter, J; Bottura, L


    The electrical resistance of Large Hadron Collider main busbar cable lap splices produced by soft soldering has been measured with two independent methods as a function of intercable contact area and for splices made of cables with various defects. For defect-free lap splices, the resistance increases from 0.3 to 10 nΩ (at 4.3 K in self-field) when reducing the cable overlap length from 120 to 3 mm, as expected assuming that the resistance is inversely proportional to the intercable contact area. The resistance of bridge splices that connect side-by-side cables can be predicted from the lap splice resistances and the overlap areas involved.

  19. Application of Superconducting Power Cables to DC Electric Railway Systems (United States)

    Ohsaki, Hiroyuki; Lv, Zhen; Sekino, Masaki; Tomita, Masaru

    For novel design and efficient operation of next-generation DC electric railway systems, especially for their substantial energy saving, we have studied the feasibility of applying superconducting power cables to them. In this paper it is assumed that a superconducting power cable is applied to connect substations supplying electric power to trains. An analysis model line was described by an electric circuit, which was analyzed with MATLAB-Simulink. From the calculated voltages and currents of the circuit, the regenerative brake and the energy losses were estimated. In addition, assuming the heat loads of superconducting power cables and the cryogenic efficiency, the energy saving of the total system was evaluated. The results show that the introduction of superconducting power cables could achieve the improved use of regenerative brake, the loss reduction, the decreased number of substations, the reduced maintenance, etc.

  20. 78 FR 12967 - Broadcast Services; Children's Television; Cable Operators (United States)


    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 Broadcast Services; Children's Television; Cable Operators AGENCY: Federal Communications Commission. ACTION: Final rule; announcement of effective date. SUMMARY: This document announces...

  1. Stability of Superconducting Rutherford Cables For accelerator magnets

    CERN Document Server

    Willering, GP; Verweij, A P


    The stability of superconducting magnets has a high priority for particle accelerators, since the operational time and operational collision energy depend strongly on it. Local heat dissipation due to beam loss and conductor movement is inevitable, causing local hot spots in the conductor, possibly leading to magnet quench. For stability against local and transient energy deposition, the cable is the most important unit to investigate. Most superconducting accelerator magnets are wound from Rutherford cables with a flat cable layout, consisting of twisted strands. The mechanisms of normal zone propagation in Rutherford cables have been described in detail with experimental and modeling data. The onset of a local normal zone forces current to redistribute in adjacent neighboring superconducting strands, reducing the longitudinal normal zone propagation. Transversal normal zone propagation in adjacent and crossing strands is caused by the redistribution of current and by heat exchange. The mechanism of normal z...

  2. Magnetic Flux Leakage Sensing-Based Steel Cable NDE Technique

    National Research Council Canada - National Science Library

    Park, Seunghee; Kim, Ju-Won; Lee, Changgil; Lee, Jong-Jae


    .... This inspection system measures magnetic flux to detect the local faults (LF) of steel cable. To verify the feasibility of the proposed damage detection technique, an 8-channel MFL sensor head prototype was designed and fabricated...

  3. ALOHA Cabled Observatory (ACO): Acoustic Doppler Current Profiler (ADCP): Temperature (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The University of Hawaii's ALOHA ("A Long-term Oligotrophic Habitat Assessment") Cabled Observatory (ACO) is located 100 km north of the island of Oahu, Hawaii (22...

  4. Applicability of cable theory to vascular conducted responses

    DEFF Research Database (Denmark)

    Hald, Bjørn Olav; Jensen, Lars Jørn; Sørensen, Preben Graae


    Conduction processes in the vasculature have traditionally been described using cable theory, i.e., locally induced signals decaying passively along the arteriolar wall. The decay is typically quantified using the steady-state length-constant, ¿, derived from cable theory. However......, the applicability of cable theory to blood vessels depends on assumptions that are not necessarily fulfilled in small arteries and arterioles. We have employed a morphologically and electrophysiologically detailed mathematical model of a rat mesenteric arteriole to investigate if the assumptions hold and whether...... ¿ adequately describes simulated conduction profiles. We find that several important cable theory assumptions are violated when applied to small blood vessels. However, the phenomenological use of a length-constant from a single exponential function is a good measure of conduction length. Hence, ¿ should...

  5. 78 FR 1823 - Cable Television Technical and Operational Requirements (United States)


    ... From the Federal Register Online via the Government Publishing Office ] FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 79 Cable Television Technical and Operational Requirements AGENCY: Federal Communications Commission. ACTION: Proposed rule; extension of reply comment period. SUMMARY: In this document...

  6. Calculating Parameters for a ReBCO Cable Joint Terminal

    CERN Document Server

    Vipp, Venno


    The aim of this project was to evaluate the effects of temperature and length on the design of a joint for a 6-around 1 CORC based conductor and optimize the terminal geometry for a single strand cable.

  7. Loss and Inductance Investigation in Superconducting Cable Conductors

    DEFF Research Database (Denmark)

    Olsen, Søren Krüger; Tønnesen, Ole; Træholt, Chresten


    An important parameter in the design and optimization of a superconducting cable conductor is the control of the current distribution among single tapes and layers. This distribution is to a large degree determined by inductances, since the resistances are low. The self and mutual inductances...... of the layers are therefore studied theoretically. The current distribution between the superconducting layers is monitored as a function of transport current, and the results are compared with the expected current distribution given by our electrical circuit model.The AC-losses are measured as a function...... of transport current and current distribution.This presentation is based on a number of experiments performed on prototype superconducting cable conductors. The critical current (1uV/cm) of the conductor at 77K was 1590 A (cable #1) and 3240 A (cable #2) respectively.At an rms current of 2 kA (50 Hz) the AC...

  8. Development of YBCO HTS cable with low AC loss

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, M. [Energy Transmission Research Department Ecology and Energy Laboratory, Furukawa Electric Co., Ltd., 6, Yawata-Kaigandori, Ichihara, Chiba 290-8555 (Japan)], E-mail:; Mukoyama, S. [Energy Transmission Research Department Ecology and Energy Laboratory, Furukawa Electric Co., Ltd., 6, Yawata-Kaigandori, Ichihara, Chiba 290-8555 (Japan); Amemiya, N. [Yokohama National University, 79-5, Tokiwadai, Hodogaya, Yokohama 240-8501 (Japan); Nagaya, S.; Kashima, N. [Chubu Electric Power Co., Inc., 20-1, Kitasekiyama, Ohdaka-cho, Midori-ku, Nagoya 459-8522 (Japan); Shiohara, Y. [Superconductivity Research Laboratory, 1-10-13, Shinonome, Koto-ku, Tokyo 135-0062 (Japan)


    High temperature superconducting (HTS) cables using YBCO tapes are expected to be more economical because AC losses will be much smaller than conventional cables. To reduce AC loss, 10 mm wide YBCO tapes were divided into five strips using a YAG laser. Using narrower strips and optimizing the space between the strips were effective in reducing AC loss. A 1 m conductor was fabricated, and AC loss was 0.048 W/m at 1 kA and 50 Hz. Based on the successful AC loss reduction in the 1 m conductor, we will fabricate a 10 m HTS cable with a three-layer HTS conductor, electrical insulation, and a one-layer HTS shield and cupper protection layer for overcurrent. In addition, we have developed a prototype of the HTS cable joint that can withstand an overcurrent condition of 31.5 kA for 2 s.

  9. LOFT 3C cable tray and ladder seismic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mosby, W.R.


    The LOFT 3C cable tray and ladder were analyzed for LOCE and Safe Shutdown Earthquake (SSE) seismic loads by using equivalent static loads. Design changes were recommended to alleviate overstress conditions.

  10. ALOHA Cabled Observatory (ACO): Acoustic Doppler Current Profiler (ADCP): Velocity (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The University of Hawaii's ALOHA ("A Long-term Oligotrophic Habitat Assessment") Cabled Observatory (ACO) is located 100 km north of the island of Oahu, Hawaii (22...

  11. Security an introduction

    CERN Document Server

    Purpura, Philip P


    Section I The History and Profession of SecurityDefinition, Role, and History of Security Security Defined The Contexts of Security The Roles of Security The History of Security Security in an Environment of Threats, Terrorism, and All-Hazards Threats and Hazards Terrorism National Strategies The Profession and Business of Security The Business of Security Professionalism and Security Associations Ethics Regulation of the Security Industry Security Training Higher Education Careers Section II Protecting People and AssetsSecurity Methodology Methodology Defined Security Business Proposals Secur


    Directory of Open Access Journals (Sweden)

    Dorina Ardelean


    Full Text Available The assurance of food security at the individual level doesn’t implicitly provide for the one at family level as the concepts of hunger, malnutrition and food insecurity are the steps of the same process of access restricted to a sufficient supply of food. In order to achieve food security at the individual level the following is necessary: ensuring food availability (production, reserve stocks; redistribution of food availability within the country or out through international exchanges; effective access of the population to purchase food consumer goods, by ensuring its effective demand as required. Food security of families (FFS is required for assuring individual food security (IFS, but it is not sufficient because the food available may be unevenly distributed between family members. National food security (NFS corresponds to the possibilities that different countries have to ensure both FFS and IFS without sacrificing other important objectives. Under the name of GAS is defined the global food security which represents permanent access for the entire population of the globe to the necessary food for a healthy and active life.

  13. Multi-core Fibers in Submarine Networks for High-Capacity Undersea Transmission Systems

    DEFF Research Database (Denmark)

    Nooruzzaman, Md; Morioka, Toshio


    Application of multi-core fibers in undersea networks for high-capacity submarine transmission systems is studied. It is demonstrated how different architectures of submerged branching unit affect network component counts in long-haul undersea transmission systems......Application of multi-core fibers in undersea networks for high-capacity submarine transmission systems is studied. It is demonstrated how different architectures of submerged branching unit affect network component counts in long-haul undersea transmission systems...

  14. They Have Not Yet Begun to Fight: Women in the United States Navy Submarine Fleet (United States)


    Navy Nurse Corps in 1908. The Nurse Corps was highly educated for the time and maintained high professional standards.3 Regardless, the struggle to...nation’s navies who integrated women into their submarine fleets ahead of the U.S. Navy. Norway, Sweden , Australian, and Great Britain all...Nations such as Norway and Sweden have been incorporating females into their submarines since the mid-1980s. 39 Sweden has had female sailors

  15. The Close Aboard Bastion: a Soviet ballistic missile submarine deployment strategy


    Kreitler, Walter M


    Approved for public release; distribution is unlimited This thesis describes and analyzes a possible deployment posture for the Soviet ballistic missile submarine force. It examines the proposition that the Soviet Navy will establish a point defense, labeled "Close Aboard Bastions" (CABs), for its ballistic missile submarine fleet within the Soviet claimed 12 nautical mile territorial sea. This is a logical derivation of the currently widely held view that the Soviets will estab...

  16. Emerging Subsea Networks: SMART Cable Systems for Science and Society (United States)

    Howe, B. M.; Butler, R.; Joint Task Force, U.


    The subsea telecommunications cable industry is approaching a prospective new era: deploying SMART subsea cable systems (SMART = Science Monitoring And Reliable Telecommunication). The current global, commercial cable infrastructure consists of 1 Gm of cable, being refreshed now and expanding in the future. The SMART concept is to add a small external sensor package along the cable system at its optical repeaters to transmit important real-time environmental data via a dedicated wavelength or overhead channel in the transmission system, avoiding any impact on the commercial traffic. These small, reliable, existing sensors would precisely measure temperature, pressure and three-axis acceleration across the world's ocean floor over an extended period of time, being deployed using standard cable-laying procedures on new or refurbished cables, but not requiring maintenance through the 2-3 decade life of the cable systems. The game-changing factor is the urgent international need for ocean environmental data related to mitigating climate and sea-level change and improving tsunami and slope failure hazard warnings. Societal costs incurred by these are reaching billions of dollars and hundreds of thousands of deaths. Pressures for new and urgent public policies are evident from the 5th IPCC Assessment, USA-China agreement on limiting greenhouse gas emissions, clear evidence for rapid global warming, 21st Session of the Conference of the Parties to the UNFCCC (December 2015, Paris), and the scale of the costs of inaction. To support revised public policies and actions, decision-makers, industry leaders, and the public are seeking key scientific data, which will necessitate new sources of funding. Hence, the emergence of new SMART cable systems offered by the subsea telecommunications industry will provide new market opportunities, engage additional non-traditional users, and make profound societal contributions. The Joint Task Force (JTF) on SMART Subsea Cable Systems

  17. An enhanced fire hazard assessment model and validation experiments for vertical cable trays

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lu [Sate Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230027 (China); Huang, Xianjia, E-mail: [Joint Laboratory of Fire Safety in Nuclear Power Plants, Institute of Industry Technology Guangzhou & Chinese Academy of Sciences, Guangzhou 511458 (China); Bi, Kun; Liu, Xiaoshuang [China Nuclear Power Design Co., Ltd., Shenzhen 518045 (China)


    Highlights: • An enhanced model was developed for vertical cable fire hazard assessment in NPP. • The validated experiments on vertical cable tray fires were conducted. • The capability of the model for cable tray with different cable spacing were tested. - Abstract: The model, referred to as FLASH-CAT (Flame Spread over Horizontal Cable Trays), was developed to estimate the heat release rate for vertical cable tray fire. The focus of this work is to investigate the application of an enhanced model to the single vertical cable tray fires with different cable spacing. The experiments on vertical cable tray fires with three typical cable spacing were conducted. The histories of mass loss rate and flame length were recorded during the cable fire. From the experimental results, it is found that the space between cable lines intensifies the cable combustion and accelerates the flame spread. The predictions by the enhanced model show good agreements with the experimental data. At the same time, it is shown that the enhanced model is capable of predicting the different behaviors of cable fires with different cable spacing by adjusting the flame spread speed only.

  18. Electromagnetic analysis of current distribution in multistrand superconducting cables

    CERN Document Server

    Bottura, L; Negrini, F; Ribani, P L; Sandiumenge, F; Fontcuberta, J


    A new electromagnetic model for the simulation of transients in superconducting coils is presented. The model takes into account the non uniform current distribution in a multistrand cable. From Maxwell equations, a system of partial differential equations is obtained which describes the space and time dependence of current in the strands of the cable. The system is numerically solved by means of the finite element method. Comparison of numerical results with experimental ones is shown. (6 refs).

  19. CECOM Index of Technical Papers, International Wire and Cable Symposia, (United States)



  20. Usage of Cable Bolts for Gateroad Maintenance in Soft Rocks

    Directory of Open Access Journals (Sweden)

    Iurii Khalymendyk


    Originality/value: 1. There are no regulations and state standards in regard to cable bolt installation parameters in the mines of Ukraine, consequently the usage of cable bolts for gateroad maintenance required preliminary testing under geological conditions at the Western Donbass mines with soft enclosing rocks. 2. Combining levelling with observations using extensometers allowed for the detection of the rock layers' uniform sagging zone in the roof of the gateroad.