WorldWideScience

Sample records for breakers resolve trip

  1. Retrofit breakers resolve trip failures

    International Nuclear Information System (INIS)

    Hanna, G.L.

    1995-01-01

    This articles examines how power plants can use advance planning and retrofit equipment to upgrade existing systems while avoiding unnecessary downtime. A break that fails to open challenges the safety features of a nuclear power plant. To ensure reliable operations, the utility selected a comprehensive retrofit program to replace a third of the 200 breakers originally installed at the Shearon Harris Nuclear Power Plant. Under contract, the retrofits--Siemens RLN breakers--were built and qualified for nuclear service by Wyle Laboratories through a special teaming agreement with Siemens Energy and Automation. The project offers an excellent example of how a utility can use advance planning and retrofit equipment to upgrade its existing systems while avoiding unnecessary downtime

  2. IE Information Notice No. 85-64: BBC Brown Boveri low-voltage K-line circuit breakers, with deficient overcurrent trip devices models OD-4 and 5

    International Nuclear Information System (INIS)

    Jordan, E.L.

    1992-01-01

    On May 13, 1985, BBC Brown Boveri Inc. (BBC) made a 10 CFR Part 21 report to the NRC concerning a deficiency in the Models OD-4 and OD-5 overcurrent trip devices installed on K-line circuit breakers. The affected breakers were manufactured by BBC from October 1983 to March 1985 and may have incorrect short time delay band levers (links) installed in electromechanical overcurrent trip device models OD-4 and OD-5. The incorrect link could limit the travel of the short time armature and cause the short time element to be inoperative in the maximum (MAX) band. The May 13, 1985, report recommended that all K-line circuit breakers with the OD-4 and OD-5 overcurrent trip devices and any spare OD-4 and OD-5 overcurrent trip devices that were manufactured between October 1983 and March 1985, be inspected for an incorrect short time delay band link. Licensees known by BBC to have purchased K-line breakers or spare OD-4 or OD-5 overcurrent trip devices were notified of the possible defect and instructions provided for their inspection. Enclosed is a list of utilities and related facilities that were notified by BBC. However, BBC advised the NRC that there is a possibility that other utilities could be using K-line circuit breakers with the suspect OD-4 and OD-5 overcurrent trip devices. Therefore, all licensees are being notified of this possible defect

  3. NRC Information Notice No. 93-22: Tripping of Klockner-Moeller molded-case circuit breakers due to support lever failure

    International Nuclear Information System (INIS)

    Grimes, B.K.

    1993-01-01

    On July 1, 1992, Virginia Electric and Power Company (VEPCO), licensee for North Anna Power Station (North Anna), Units 1 and 2, reported to the NRC that over a three-month period in 1992, three K-M model NZM6-63, 480-Vac MCCBs had tripped without appreciable load or fault condition or other electrical or mechanical transient. The three failed MCCBs were located in the cable vault and tunnel area of North Anna-2 and supplied power to motor operated valves in the charging and safety injection systems. The switch handles were found in the trip-free position and the breakers could not be relatched and reclosed. Examination of the internals of one of the three failed breakers revealed that its support lever (also described by VEPCO as a ''spring arm''), located in the rear compartment of the case, had fractured. This caused the breaker to trip and to become incapable of being reclosed. The NRC has determined that the support levers only in K-M model NZM6, NZM6b, and NZMH6 MCCBs, rated for 100 amperes and below and manufactured from 1972 on, have been made of the same type of plastic used in the support levers of the MCCBs that failed at North Anna-2

  4. Circuit breaker operation and potential failure modes during an earthquake

    International Nuclear Information System (INIS)

    Lambert, H.E.; Budnitz, R.J.

    1987-01-01

    This study addresses the effect of a strong-motion earthquake on circuit breaker operation. It focuses on the loss of offsite power (LOSP) transient caused by a strong-motion earthquake at the Zion Nuclear Power Plant. This paper also describes the operator action necessary to prevent core melt if the above circuit breaker failure modes occur simultaneously on three 4.16 KV buses. Numerous circuit breakers important to plant safety, such as circuit breakers to diesel generators and engineered safety systems (ESS), must open and/or close during this transient while strong motion is occurring. Potential seismically-induced circuit-breaker failures modes were uncovered while the study was conducted. These failure modes include: circuit breaker fails to close; circuit breaker trips inadvertently; circuit breaker fails to reclose after trip. The causes of these failure modes include: Relay chatter causes the circuit breaker to trip; Relay chatter causes anti-pumping relays to seal-in which prevents automatic closure of circuit breakers; Load sequencer failures. The incorporation of these failure modes as well as other instrumentation and control failures into a limited scope seismic probabilistic risk assessment is also discussed in this paper

  5. Automatic recloser circuit breaker integrated with GSM technology for power system notification

    Science.gov (United States)

    Lada, M. Y.; Khiar, M. S. A.; Ghani, S. A.; Nawawi, M. R. M.; Rahim, N. H.; Sinar, L. O. M.

    2015-05-01

    Lightning is one type of transient faults that usually cause the circuit breaker in the distribution board trip due to overload current detection. The instant tripping condition in the circuit breakers clears the fault in the system. Unfortunately most circuit breakers system is manually operated. The power line will be effectively re-energized after the clearing fault process is finished. Auto-reclose circuit is used on the transmission line to carry out the duty of supplying quality electrical power to customers. In this project, an automatic reclose circuit breaker for low voltage usage is designed. The product description is the Auto Reclose Circuit Breaker (ARCB) will trip if the current sensor detects high current which exceeds the rated current for the miniature circuit breaker (MCB) used. Then the fault condition will be cleared automatically and return the power line to normal condition. The Global System for Mobile Communication (GSM) system will send SMS to the person in charge if the tripping occurs. If the over current occurs in three times, the system will fully trip (open circuit) and at the same time will send an SMS to the person in charge. In this project a 1 A is set as the rated current and any current exceeding a 1 A will cause the system to trip or interrupted. This system also provides an additional notification for user such as the emergency light and warning system.

  6. Age-related degradation of Westinghouse 480-volt circuit breakers

    International Nuclear Information System (INIS)

    Subudhi, M.; Shier, W.; MacDougall, E.

    1990-07-01

    An aging assessment of Westinghouse DS-series low-voltage air circuit breakers was performed as part of the Nuclear Plant Aging Research (NPAR) program. The objectives of this study are to characterize age-related degradation within the breaker assembly and to identify maintenance practices to mitigate their effect. Since this study has been promulgated by the failures of the reactor trip breakers at the McGuire Nuclear Station in July 1987, results relating to the welds in the breaker pole lever welds are also discussed. The design and operation of DS-206 and DS-416 breakers were reviewed. Failure data from various national data bases were analyzed to identify the predominant failure modes, causes, and mechanisms. Additional operating experiences from one nuclear station and two industrial breaker-service companies were obtained to develop aging trends of various subcomponents. The responses of the utilities to the NRC Bulletin 88-01, which discusses the center pole lever welds, were analyzed to assess the final resolution of failures of welds in the reactor trips. Maintenance recommendations, made by the manufacturer to mitigate age-related degradation were reviewed, and recommendations for improving the monitoring of age-related degradation are discussed. As described in Volume 2 of this NUREG, the results from a test program to assess degradation in breaker parts through mechanical cycling are also included. The testing has characterized the cracking of center-pole lever welds, identified monitoring techniques to determine aging in breakers, and provided information to augment existing maintenance programs. Recommendations to improve breaker reliability using effective maintenance, testing, and inspection programs are suggested. 13 refs., 21 figs., 8 tabs

  7. Electrical, Magnetic, Thermal Modeling and Analysis of a 5000A Solid-State Switch Module and Its Application as a DC Circuit Breaker

    OpenAIRE

    Zhou, Xigen

    2005-01-01

    This dissertation presents a systematic design and demonstration of a novel solid-state DC circuit breaker. The mechanical circuit breaker is widely used in power systems to protect industrial equipment during fault or abnormal conditions. Compared with the slow and high-maintenance mechanical circuit breaker, the solid-state circuit breaker is capable of high-speed interruption of high currents without generating an arc, hence it is maintenance-free. Both the switch and the tripping unit ...

  8. Control rod trip failures; Salem 1, the cause, response, and potential fixes

    International Nuclear Information System (INIS)

    Hall, R.E.; Boccio, J.L.; Luckas, W.J.

    1984-01-01

    This chapter presents a systems and reliability analysis of recent nuclear reactor control rod failure-to-trip (or scram) events that have been experienced in the US commercial nuclear industry. The operational factors of hardware, procedures, and human error are considered in the analysis of transients without scram. The 1980 Browns Ferry 3 scram system failure is analyzed to contrast the two 1983 Salem 1 events. The details of the Salem control rod failure to trip are investigated and used to calculate the reactor protection system unavailabilities. The internal reactor trip breaker logic is reviewed as related to the Westinghouse DB-50 breaker application. The impact of test and maintenance on system challenges is discussed. It is concluded that although the failure to trip or scram represents a single class of initiators, the actual events of each transient are operationally unique and require individual human responses

  9. Trend analysis of breaker events at United States nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Hiroki

    2006-01-01

    From events in overseas nuclear power plants recorded in the nuclear information detabase of Institute of Nuclear Safety System, Inc. (INSS), the number of events of electrical systems during the four years from 2002 to 2005 was extracted and the trend was analyzed. The results showed that breaker events were the largest in number in all years, and almost all them occurred in the US. The breaker events that occurred in US nuclear power plants in 2005 were analyzed by classifying them by cause of failure and effect on the plant, and by comparing the number of occurrences with that in Japan. As a result, the main cause of many of the breaker events was improper maintenance due to poor arrangement of maintenance manuals and human error, as well as aging degradation, they can be estimated to have been caused by insufficient maintenance control and inspection. The number of breaker failures per plant per year in our country was lower than that in the US by an order of magnitude, and there were no failures that led to a plant trip or power reduction. These facts suggest that our country's maintenance contents of breaker are advantage. (author)

  10. Feasibility analysis of a novel hybrid-type superconducting circuit breaker in multi-terminal HVDC networks

    International Nuclear Information System (INIS)

    Khan, Umer Amir; Lee, Jong-Geon; Seo, In-Jin; Amir, Faisal; Lee, Bang-Wook

    2015-01-01

    Highlights: • A novel hybrid-type superconducting circuit breaker (SDCCB) is proposed. • SDCCB has SFCL located in the main current path to limit the fault current until the final trip signal. • SFCL in SDCCB suppressed the fast rising DC fault current for a predefined time. • SFCL significantly reduced the DC current breaking stress on SDCCB components. • SDCCB isolated the HVDC faulty line in three, four, and five converter stations MTDC. - Abstract: Voltage source converter-based HVDC systems (VSC-HVDC) are a better alternative than conventional thyristor-based HVDC systems, especially for developing multi-terminal HVDC systems (MTDC). However, one of the key obstacles in developing MTDC is the absence of an adequate protection system that can quickly detect faults, locate the faulty line and trip the HVDC circuit breakers (DCCBs) to interrupt the DC fault current. In this paper, a novel hybrid-type superconducting circuit breaker (SDCCB) is proposed and feasibility analyses of its application in MTDC are presented. The SDCCB has a superconducting fault current limiter (SFCL) located in the main current path to limit fault currents until the final trip signal is received. After the trip signal the IGBT located in the main line commutates the current into a parallel line where DC current is forced to zero by the combination of IGBTs and surge arresters. Fault simulations for three-, four- and five-terminal MTDC were performed and SDCCB performance was evaluated in these MTDC. Passive current limitation by SFCL caused a significant reduction of fault current interruption stress in the SDCCB. It was observed that the DC current could change direction in MTDC after a fault and the SDCCB was modified to break the DC current in both the forward and reverse directions. The simulation results suggest that the proposed SDCCB could successfully suppress the DC fault current, cause a timely interruption, and isolate the faulty HVDC line in MTDC.

  11. Feasibility analysis of a novel hybrid-type superconducting circuit breaker in multi-terminal HVDC networks

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Umer Amir [Hanyang University, Sa-3dong, Sangrok-gu, Ansan 426-791 (Korea, Republic of); National University of Sciences and Technology, PNEC Campus, Habib Rehmatullah Road, Karachi (Pakistan); Lee, Jong-Geon; Seo, In-Jin [Hanyang University, Sa-3dong, Sangrok-gu, Ansan 426-791 (Korea, Republic of); Amir, Faisal [National University of Sciences and Technology, PNEC Campus, Habib Rehmatullah Road, Karachi (Pakistan); Lee, Bang-Wook, E-mail: bangwook@hanyang.ac.kr [Hanyang University, Sa-3dong, Sangrok-gu, Ansan 426-791 (Korea, Republic of)

    2015-11-15

    Highlights: • A novel hybrid-type superconducting circuit breaker (SDCCB) is proposed. • SDCCB has SFCL located in the main current path to limit the fault current until the final trip signal. • SFCL in SDCCB suppressed the fast rising DC fault current for a predefined time. • SFCL significantly reduced the DC current breaking stress on SDCCB components. • SDCCB isolated the HVDC faulty line in three, four, and five converter stations MTDC. - Abstract: Voltage source converter-based HVDC systems (VSC-HVDC) are a better alternative than conventional thyristor-based HVDC systems, especially for developing multi-terminal HVDC systems (MTDC). However, one of the key obstacles in developing MTDC is the absence of an adequate protection system that can quickly detect faults, locate the faulty line and trip the HVDC circuit breakers (DCCBs) to interrupt the DC fault current. In this paper, a novel hybrid-type superconducting circuit breaker (SDCCB) is proposed and feasibility analyses of its application in MTDC are presented. The SDCCB has a superconducting fault current limiter (SFCL) located in the main current path to limit fault currents until the final trip signal is received. After the trip signal the IGBT located in the main line commutates the current into a parallel line where DC current is forced to zero by the combination of IGBTs and surge arresters. Fault simulations for three-, four- and five-terminal MTDC were performed and SDCCB performance was evaluated in these MTDC. Passive current limitation by SFCL caused a significant reduction of fault current interruption stress in the SDCCB. It was observed that the DC current could change direction in MTDC after a fault and the SDCCB was modified to break the DC current in both the forward and reverse directions. The simulation results suggest that the proposed SDCCB could successfully suppress the DC fault current, cause a timely interruption, and isolate the faulty HVDC line in MTDC.

  12. Feasibility analysis of a novel hybrid-type superconducting circuit breaker in multi-terminal HVDC networks

    Science.gov (United States)

    Khan, Umer Amir; Lee, Jong-Geon; Seo, In-Jin; Amir, Faisal; Lee, Bang-Wook

    2015-11-01

    Voltage source converter-based HVDC systems (VSC-HVDC) are a better alternative than conventional thyristor-based HVDC systems, especially for developing multi-terminal HVDC systems (MTDC). However, one of the key obstacles in developing MTDC is the absence of an adequate protection system that can quickly detect faults, locate the faulty line and trip the HVDC circuit breakers (DCCBs) to interrupt the DC fault current. In this paper, a novel hybrid-type superconducting circuit breaker (SDCCB) is proposed and feasibility analyses of its application in MTDC are presented. The SDCCB has a superconducting fault current limiter (SFCL) located in the main current path to limit fault currents until the final trip signal is received. After the trip signal the IGBT located in the main line commutates the current into a parallel line where DC current is forced to zero by the combination of IGBTs and surge arresters. Fault simulations for three-, four- and five-terminal MTDC were performed and SDCCB performance was evaluated in these MTDC. Passive current limitation by SFCL caused a significant reduction of fault current interruption stress in the SDCCB. It was observed that the DC current could change direction in MTDC after a fault and the SDCCB was modified to break the DC current in both the forward and reverse directions. The simulation results suggest that the proposed SDCCB could successfully suppress the DC fault current, cause a timely interruption, and isolate the faulty HVDC line in MTDC.

  13. Age-related degradation of Westinghouse 480-volt circuit breakers

    International Nuclear Information System (INIS)

    Subudhi, M.; MacDougall, E.; Kochis, S.; Wilhelm, W.; Lee, B.S.

    1990-11-01

    After the McGuire event in 1987 relating to failure of the center pole weld in one of its reactor trip breakers, activities were initiated by the NRC to investigate the probable causes. A review of operating experience suggested that the burning of coils, jamming of the operating mechanism, and deterioration of the contacts dominated the breakers failures. Although failures of the pole shaft weld were not included as one of the generic problems, the NRC augmented inspection team had suspected that these welds were substandard which led them to crack prematurely. A DS-416 low voltage air circuit breaker manufactured by Westinghouse was mechanically cycled to identify age-related degradations. This accelerated aging test was conducted for over 36,000 cycles during nine months. Three separate pole shafts, one with a 60 degree weld, one with a 120 degree and one with a 180 degree were used to characterize the cracking in the pole level welds. In addition, three different operating mechanisms and several other parts were replaced as they became inoperable. The testing yielded many useful results. The burning of the closing coils was found to be the effect of binding in the linkages that are connected to this device. Among the seven welds on the pole shaft, number-sign 1 and number-sign 3 were the critical ones which cracked first to cause misalignment of the pole levers, which, in turn, had led to many problems with the operating mechanism including the burning of coils, excessive wear in certain parts, and overstressed linkages. Based on these findings, a maintenance program is suggested to alleviate the age-related degradations that occur due to mechanical cycling of this type of breaker. 3 refs., 39 figs., 7 tabs

  14. IE Information Notice No. 85-93: Westinghouse Type DS circuit breakers, potential failure of electric closing feature because of broken spring release latch lever

    International Nuclear Information System (INIS)

    Jordan, E.L.

    1992-01-01

    On April 14, 1985, the Westinghouse Nuclear Services Integration Division (NSID) issued Technical Bulletin No. NSID-TB-85-17 advising their customers of a potential malfunction in Westinghouse Type DS Class 1E circuit breakers because of broken spring release latch levers. These electrically operated type DS breakers will not close electrically when the spring release latch lever has been broken off. Twenty-five broken levers have been reported and evaluated. This evaluation shows concentrations of incidents traceable to manufacturing in the following periods of time: early 1975, April 1976, and early 1978. This circuit breaker failure, as discussed, adversely affects the safety function (closing on demand) when the circuit breaker is used in the Engineered Safety Features Systems. However, this failure mode will not affect the safety trip function when it is used in the reactor protection system

  15. Investigation of a turbulent spot and a tripped turbulent boundary layer flow using time-resolved tomographic PIV

    NARCIS (Netherlands)

    Schröder, A.; Geisler, R.; Elsinga, G.E.; Scarano, F.; Dierksheide, U.

    2007-01-01

    In this feasibility study the tomographic PIV technique has been applied to time resolved PIV recordings for the study of the growth of a turbulent spot in a laminar flat plate boundary layer and to visualize the topology of coherent flow structures within a tripped turbulent flat plate boundary

  16. Hydraulic actuator for an electric circuit breaker

    Science.gov (United States)

    Imam, Imdad [Colonie, NY

    1983-01-01

    This actuator comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit breaker opening operation. The breaker-opening space and the breaker-closing space are connected by an impeded flow passage. A pilot valve opens to allow the pressurized liquid in the breaker-closing space to flow to a back chamber of a normally closed main valve to cause the main valve to be opened during a circuit breaker opening operation to release the pressurized liquid from the breaker-closing space. An impeded passage affords communication between the back chamber and a sump located on the opposite side of the main valve from the back chamber. The pilot valve and impeded passage allow rapid opening of the main valve with pressurized liquid from the breaker closing side of the piston.

  17. Retran simulation of Oyster Creek generator trip startup test

    International Nuclear Information System (INIS)

    Alammar, M.A.

    1987-01-01

    RETRAN simulation of Oyster Creek generator trip startup test was carried out as part of Oyster Creek RETRAN model qualification program for reload licensing applications. The objective of the simulation was to qualify the turbine model and its interface with the control valve and bypass systems under severe transients. The test was carried out by opening the main breakers at rated power. The turbine speed governor closed the control valves and the pressure regulator opened the bypass valves within 0.5 sec. The stop valves closed by a no-load turbine trip, before the 10 percent overspeed trip was reached and the reactor scrammed on high APRM neutron flux. The simulation resulted in qualifying a normalized hydraulic torque for the turbine model and a 0.3 sec, delay block for the bypass model to account for the different delays in the hydraulic linkages present in the system. One-dimensional kinetics was used in this simulation

  18. AUTOMATED ANALYSIS OF BREAKERS

    Directory of Open Access Journals (Sweden)

    E. M. Farhadzade

    2014-01-01

    Full Text Available Breakers relate to Electric Power Systems’ equipment, the reliability of which influence, to a great extend, on reliability of Power Plants. In particular, the breakers determine structural reliability of switchgear circuit of Power Stations and network substations. Failure in short-circuit switching off by breaker with further failure of reservation unit or system of long-distance protection lead quite often to system emergency.The problem of breakers’ reliability improvement and the reduction of maintenance expenses is becoming ever more urgent in conditions of systematic increasing of maintenance cost and repair expenses of oil circuit and air-break circuit breakers. The main direction of this problem solution is the improvement of diagnostic control methods and organization of on-condition maintenance. But this demands to use a great amount of statistic information about nameplate data of breakers and their operating conditions, about their failures, testing and repairing, advanced developments (software of computer technologies and specific automated information system (AIS.The new AIS with AISV logo was developed at the department: “Reliability of power equipment” of AzRDSI of Energy. The main features of AISV are:· to provide the security and data base accuracy;· to carry out systematic control of breakers conformity with operating conditions;· to make the estimation of individual  reliability’s value and characteristics of its changing for given combination of characteristics variety;· to provide personnel, who is responsible for technical maintenance of breakers, not only with information but also with methodological support, including recommendations for the given problem solving  and advanced methods for its realization.

  19. Circuit breaker and bus

    International Nuclear Information System (INIS)

    Vogel, H.F.

    1978-01-01

    Two close-open operations are required each pulse cycle at approximately 3 MA with the breaker in series with the burn supply, both forming a leg in parallel with the E-coil and the homopolar. To conduct the 3-MA current, approximately 30 breaker units are connected in parallel. Each unit is equipped with a counterpulse capacitor bank, and the bus for the 30 units is provided with a common saturable reactor core made of strip steel wound around the bus. Oil breakers of a special design are chosen because of their high arc resistance facilitating the current transfer to the homopolar machine and for obtaining precision timing in opening and closing of the contacts. The precision timing is achieved by a shock wave method with the oil serving as hydraulic medium. Each of the parallel breaker units possesses two sets of contacts, a stationary and a transient one. A 1-mΩ resistor in series with the transient contacts of each breaker unit is to improve the current sharing. The bus consists of room temperature copper, stranded and transposed to help provide current equalization under transient conditions

  20. Rectifier cabinet static breaker

    International Nuclear Information System (INIS)

    Costantino, R.A. Jr; Gliebe, R.J.

    1992-01-01

    A rectifier cabinet static breaker replaces a blocking diode pair with an SCR and the installation of a power transistor in parallel with the latch contactor to commutate the SCR to the off state. The SCR serves as a static breaker with fast turnoff capability providing an alternative way of achieving reactor scram in addition to performing the function of the replaced blocking diodes. The control circuitry for the rectifier cabinet static breaker includes on-line test capability and an LED indicator light to denote successful test completion. Current limit circuitry provides high-speed protection in the event of overload. 7 figs

  1. Rectifier cabinet static breaker

    Science.gov (United States)

    Costantino, Jr, Roger A.; Gliebe, Ronald J.

    1992-09-01

    A rectifier cabinet static breaker replaces a blocking diode pair with an SCR and the installation of a power transistor in parallel with the latch contactor to commutate the SCR to the off state. The SCR serves as a static breaker with fast turnoff capability providing an alternative way of achieving reactor scram in addition to performing the function of the replaced blocking diodes. The control circuitry for the rectifier cabinet static breaker includes on-line test capability and an LED indicator light to denote successful test completion. Current limit circuitry provides high-speed protection in the event of overload.

  2. Commutation circuit for an HVDC circuit breaker

    Science.gov (United States)

    Premerlani, William J.

    1981-01-01

    A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components.

  3. Hydraulically-activated operating system for an electric circuit breaker

    Science.gov (United States)

    Imam, Imdad; Barkan, Philip

    1979-01-01

    This operating system comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit-breaker opening operation. A normally-closed valve located on the breaker-closing-side of the piston is openable to release liquid from the breaker-closing space so that pressurized liquid in the breaker-opening space can drive the piston in an opening direction. Means is provided for restoring the valve to its closed position following the circuit-breaker opening operation. An impeded passage affords communication between the accumulator and the breaker-closing space to allow pressurized liquid to flow from the accumulator to the breaker-closing space and develop a pressure therein substantially equal to accumulator pressure when the valve is restored to closed position following breaker-opening. This passage is so impeded that the flow therethrough from the accumulator into the breaker-closing space is sufficiently low during initial opening motion of the piston through a substantial portion of its opening stroke as to avoid interference with said initial opening motion of the piston.

  4. Switching phenomena in high-voltage circuit breakers

    International Nuclear Information System (INIS)

    Nakanishi, K.

    1991-01-01

    The topics covered in this book include: general problems concerning current interruption, the physical arc model, and miscellaneous types of modern switching apparatus, such as gas circuit breakers, gas-insulated switch-gear, vacuum circuit breakers and high-voltage direct-current circuit breakers

  5. NRC Information No. 90-41: Potential failure of General Electric Magne-Blast circuit breakers and AK circuit breakers

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    This information notice is intended to alert addressees to potential safety concerns that may result from failures of GE vertical lift (AM) and horizontal draw-out (AMH) Magne-Blast circuit breakers utilizing ML-13 operating mechanisms to open or close them and AK circuit breakers. The particular breaker failures reported herein were caused by operating problems with prop springs, snap rings and lubricating grease. GE Nuclear Energy has informed the NRC that it is aware of these problems and that GE routinely checks and corrects them if the circuit breakers are serviced at one of the four GE nuclear service centers in the US. However, the NRC is aware that some utilities may have their circuit breakers repaired or serviced at facilities other than the four GE nuclear service centers

  6. What's new about generator circuit breakers

    International Nuclear Information System (INIS)

    Kolarik, P.L.

    1979-01-01

    The need for updating ANSI C37 Standards for AC high-voltage circuit breakers has become necessary because of the increased interest in power circuit breakers for generator application. These circuit breakers, which have continuous current ratings and rated short-circuit currents that are much higher than those presently covered by existing C37 Standards, take on added importance because they are being installed in critical AC power supplies at nuclear power stations

  7. 30 CFR 75.800-1 - Circuit breakers; location.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit breakers; location. 75.800-1 Section 75.800-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... § 75.800-1 Circuit breakers; location. Circuit breakers protecting high-voltage circuits entering an...

  8. 30 CFR 75.900-1 - Circuit breakers; location.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit breakers; location. 75.900-1 Section 75.900-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Alternating Current Circuits § 75.900-1 Circuit breakers; location. Circuit breakers used to protect low-and...

  9. Analytical Analysis and Case Study of Transient Behavior of Inrush Current in Power Transformer for Designing of Efficient Circuit Breakers

    Science.gov (United States)

    Harmanpreet, Singh, Sukhwinder; Kumar, Ashok; Kaur, Parneet

    2010-11-01

    Stability & security are main aspects in electrical power systems. Transformer protection is major issue of concern to system operation. There are many mall-trip cases of transformer protection are caused by inrush current problems. The phenomenon of transformer inrush current has been discussed in many papers since 1958. In this paper analytical analysis of inrush current in a transformer switched on dc and ac supply has been done. This analysis will help in design aspects of circuit breakers for better performance.

  10. A mechanical arcless dc circuit breaker for a superconducting magnet system

    International Nuclear Information System (INIS)

    Yamaguchi, S.; Sasao, H.; Matumura, Y.; Tukamoto, T.

    1993-01-01

    Next fusion research experiments plan to use many superconducting magnets. When a quench phenomenon is observed, the current should be interrupted to protect the magnet. Therefore, a dc circuit breaker is necessary. There are four technical situations to be considered for the dc circuit breaker system; (1) high rated current, (2) smaller size breaker, (3) high reliability and (4) no surge voltage during the interruption. The sizer of the breaker is limited by the arc current density of the contacts, and the low current density is better in the circuit breakers. A high rated current also needs the large contacts of the breaker. Here, we introduce a new type of dc circuit breaker system which does not generate an arc plasma between the contacts, equip the high rated current disconnecting switch and a fuse for the failure of the interruption, and use the conventional ac breaker. The switch size of the breaker is almost one hundred times smaller than that of the previous switch. (orig.)

  11. Development of large-scale thyristor dc circuit breaker

    International Nuclear Information System (INIS)

    Kobayashi, S.; Tanoue, Y.; Ikegame, H.; Matushita, T.; Sato, Y.

    1981-01-01

    A study for developing a thyristor dc circuit breaker that is applicable to the Tokamak device for engineering feasibility is presented. The design and test of a unit circuit breaker consisting of 4kV-3kA thyristors connected 2 in series and 12 in parallel are described. And based on the results a 50kV-24kA thyristor dc circuit breaker is conceptually designed

  12. Arc modelling in SF6 circuit breakers

    International Nuclear Information System (INIS)

    Verite, J.C.; Boucher, T.; Comte, A.; Delalondre, C.; Robin-Jouan, P.; Serres, E.; Texier, V.; Barrault, M.; Chevrier, P.; Fievet, C.

    1995-06-01

    The paper presents the work done by an operator, EDF and two manufacturers to improve the physical models and numerical methods used to simulate the behavior of the plasma and cold gas around it in a breaking chamber of the HV SF6 circuit breaker, during the high-current phase. This work concerns flow phenomena, in particular incorporating compressibility and the study of turbulence, the coupling between these flow phenomena and electromagnetic phenomena, and finally, radiation - which plays an essential role in energy transfer during the high-current phase. For this latter aspect, emission but also absorption were proven to play a major role, and the two were introduced into the models. The paper presents the models developed and the results obtained with them for simulation of two circuit breaker mock-ups (a double-pressure circuit breaker mock-up and a self-expanding and rotating arc circuit breaker mock-up). (author)

  13. Monitoring power breakers using vibro acoustic techniques

    Directory of Open Access Journals (Sweden)

    Horia Balan

    2017-09-01

    Full Text Available Speaking about the commutation’s equipment, it can be said that the best solution in increasing reliability and lowering the maintenance costs is a continuous monitoring of the equipment. However, if the price/quality ratio is considered, it is obvious that, for the moment, the diagnosis can be also an acceptable solution. Nowadays the predictive maintenance for equipment’s diagnosis is currently replacing the preventive diagnosis. An efficient modality of lowering the maintenance costs is to online monitoring the power breakers, during their operation in the power systems. Consequently any connecting/disconnecting operations may be used in diagnosing a power breaker. Thus any supplementary and superfluous tests and/or maintenance maneuvers are avoided. The paper presents the operational maintenance in a power station with three high voltage active breakers, Areva type. The method of establishing the state of a breaker consists in the comparison between the signature of the acoustic signal provided by the manufacturer and the signal issued from the testing operation of the breaker’s state. The software processing procedure and the methodology of determining the faults of the monitored equipment are also developed. All the tests on the circuit breaker are made according the prescriptions of normative.

  14. Vision based speed breaker detection for autonomous vehicle

    Science.gov (United States)

    C. S., Arvind; Mishra, Ritesh; Vishal, Kumar; Gundimeda, Venugopal

    2018-04-01

    In this paper, we are presenting a robust and real-time, vision-based approach to detect speed breaker in urban environments for autonomous vehicle. Our method is designed to detect the speed breaker using visual inputs obtained from a camera mounted on top of a vehicle. The method performs inverse perspective mapping to generate top view of the road and segment out region of interest based on difference of Gaussian and median filter images. Furthermore, the algorithm performs RANSAC line fitting to identify the possible speed breaker candidate region. This initial guessed region via RANSAC, is validated using support vector machine. Our algorithm can detect different categories of speed breakers on cement, asphalt and interlock roads at various conditions and have achieved a recall of 0.98.

  15. WIPP site and vicinity geological field trip

    International Nuclear Information System (INIS)

    Chaturvedi, L.

    1980-10-01

    The Environmental Evaluation Group (EEG) is conducting an assessment of the radiological health risks to people from the Waste Isolation Pilot Plant (WIPP). As a part of this work, EEG is making an effort to improve the understanding of those geological issues concerning the WIPP site which may affect the radiological consequences of the proposed repository. One of the important geological issues to be resolved is the timing and the nature of the dissolution processes which may have affected the WIPP site. EEG organized a two-day conference of geological scientists, titled Geotechnical Considerations for Radiological Hazard Assessment of WIPP on January 17-18, 1980. During this conference, it was realized that a field trip to the site would further clarify the different views on the geological processes active at the site. The field trip of June 16-18, 1980 was organized for this purpose. This report provides a summary of the field trip activities along with the participants post field trip comments. Important field stops are briefly described, followed by a more detailed discussion of critical geological issues. The report concludes with EEG's summary and recommendations to the US Department of Energy for further information needed to more adequately resolve concerns for the geologic and hydrologic integrity of the site

  16. The wave vane - A device to measure the breaker angle

    Digital Repository Service at National Institute of Oceanography (India)

    Chandramohan, P.; Nayak, B.U.; Anand, N.M.

    directional wave gauge at a considerable cost. For economic and practical considerations, visual measurements on the breaker height, the breaker period and the breaker angle are generally made in the LEO pro- gramme. The breaker height is recorded... of the fins. Flag masts are fixed on either end of the arms. The whole assembly thus revolves around the spindle resting on the sleeve. WORKING PRINCIPLE The flag masts, two on the revolving arms and one on the top of the spindle lie always in a straight...

  17. Arc modelling in SF{sub 6} circuit breakers

    Energy Technology Data Exchange (ETDEWEB)

    Verite, J.C. [Electricite de France, Clamart (France). Derection des Etudes et Recherches; Boucher, T.; Comte, A. [Electricite de France, Moret sur Loing (France). Direction des Etudes et Recherches; Delalondre, C. [Electricite de France, Chatou (France). Direction des Etudes et Recherches; Robin-Jouan, P.; Serres, E.; Texier, V. [GEC Alsthom, Villeurbanne (France). Direction Technique Haute et Moyenne Tension; Barrault, M.; Chevrier, P.; Fievet, C. [CEA Centre d`Etudes Nucleaires de Grenoble, 38 (France). Merlin Gerin

    1995-06-01

    The paper presents the work done by an operator, EDF and two manufacturers to improve the physical models and numerical methods used to simulate the behavior of the plasma and cold gas around it in a breaking chamber of the HV SF6 circuit breaker, during the high-current phase. This work concerns flow phenomena, in particular incorporating compressibility and the study of turbulence, the coupling between these flow phenomena and electromagnetic phenomena, and finally, radiation - which plays an essential role in energy transfer during the high-current phase. For this latter aspect, emission but also absorption were proven to play a major role, and the two were introduced into the models. The paper presents the models developed and the results obtained with them for simulation of two circuit breaker mock-ups (a double-pressure circuit breaker mock-up and a self-expanding and rotating arc circuit breaker mock-up). (author) 10 refs.

  18. Testing of SF6- and vacuum generator circuit breakers

    NARCIS (Netherlands)

    Smeets, R.P.P.; Paske, te L.H.

    2011-01-01

    Generator circuit breakers differ in various aspects from standard distribution breakers. One of the main differences is in the electrical stresses during fault current interruption. This situation will be discussed in the present contribution, along with the standardization status and the

  19. Inductive energy storage using high voltage vacuum circuit breakers

    International Nuclear Information System (INIS)

    McCann, R.B.; Woodson, H.H.; Mukutmoni, T.

    1976-01-01

    Controlled thermonuclear fusion experiments currently being planned require large amounts of pulsed energy. Inductive energy storage systems (IES) appear to be attractive for at least two applications in the fusion research program: high beta devices and those employing turbulent heating. The well-known roadblock to successful implementation of IES is the development of a reliable and cost-effective off-switch capable of handling high currents and withstanding high recovery voltages. The University of Texas at Austin has a program to explore the application of conventional vacuum circuit breakers designed for use in AC systems, in conjunction with appropriate counter pulse circuits, as off-switches in inductive energy storage systems. The present paper describes the IES employing vacuum circuit breakers as off-switches. Since the deionization property of these circuit breakers is of great importance to the design and the cost of the counter-pulse circuit, a synthetic test installation to test these breakers has been conceived, designed and is being installed in the Fusion Research Center, University of Texas at Austin. Some design aspects of the facility will be discussed here. Finally, the results of the study on a mathematical model developed and optimized to determine the least cost system which meets both the requirements of an off-switch for IES Systems and the ratings of circuit breakers used in power systems has been discussed. This analysis indicates that the most important factor with respect to the system cost is the derating of the circuit breakers to obtain satisfactory lifetimes

  20. Assessment and modelling of switching technologies for application in HVDC-circuit breakers

    OpenAIRE

    Lund, Johan

    2011-01-01

    A key element for future DC-grids is a DC circuit breaker that in case of a short circuit fault reliably can turn off a short circuit current. AC circuit breakers are well known components that has been in use for a long time in AC-grids. The AC circuit breaker is designed to interrupt the current at its natural current zero crossings. In DC grids such does not exists, therefore AC breakers can not be directly applied in DC grids. Different concepts and technologies to solve this problem is a...

  1. NRC Information No. 87-41: Failures of certain Brown Boveri Electric circuit breakers

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    On April 20, 1987, Duquesne Light Company, the Beaver Valley Unit 2 licensee, notified the NRC of the failure of a BBE Type 5HK Class IE 4-KV circuit breaker. When the circuit breaker was racked onto the bus and 125-V DC control power was applied to the breaker's control circuit, the closing spring charged and the circuit breaker immediately closed and opened several times before the control power could be turned off. The licensee determined by field testing that the closing coil was not being energized. Another problem with BBE circuit breakers occurred at River Bend and was reported March 6, 1987. On February 6, 1987, with the unit at full power, the Division I diesel generator 4.16-KV output circuit breaker (Gould-Brown Boveri Type 5HK) failed to close during a weekly surveillance test. The licensee's inspection of the output circuit breaker revealed that a mounting bolt had fallen out of the closing spring charging motor, rendering the motor inoperable. Further investigation revealed several other circuit breakers that contained loose or missing charging motor mounting bolts. The licensee also stated that the River Bend circuit breaker preventive maintenance program, which the licensee believes to be in accordance with the vendor's recommendations, did not detect this problem. The licensee believes the root cause of the problem to be insufficient torquing of the charging motor mounting bolts by the vendor

  2. Life testing of a low voltage air circuit breaker

    International Nuclear Information System (INIS)

    Subudhi, M.; Aggarwal, S.

    1992-01-01

    A DS-416 low voltage air circuit breaker manufactured by Westinghouse was mechanically cycled to identify age-related degradation in the various breaker subcomponents, specifically the power-operated mechanism. This accelerated aging test was performed on one breaker unit for over 36,000 cycles. Three separate pole shafts, one with a 60-degree weld, one with a 120-degree weld, and one with a 180-degree weld in the third pole lever were used to characterize cracking in the welds. In addition, during the testing three different operating mechanisms and several other parts were replaced as they became inoperable. Among the seven welds on the pole shaft, number-sign 1 and number-sign 3 were found to be critical ones whose fracture can result in misalignment of the pole levers. This can lead to problems with the operating mechanism, including the burning of coils, excessive wear in certain parts, and overstressed linkages. Furthermore, the limiting service life of a number of subcomponents of the power-operated mechanism, including the operating mechanism itself, were assessed. Based on these findings, suggestions are provided to alleviate the age-related degradation that could occur as a result of normal closing and opening of the breaker contacts during its service life. Also, cause and effect analyses of various age-related degradation in various breaker parts are discussed

  3. Smart Circuit Breaker Communication Infrastructure

    Directory of Open Access Journals (Sweden)

    Octavian Mihai MACHIDON

    2017-11-01

    Full Text Available The expansion of the Internet of Things has fostered the development of smart technologies in fields such as power transmission and distribution systems (as is the Smart Grid and also in regard to home automation (the Smart Home concept. This paper addresses the network communication infrastructure for a Smart Circuit Breaker system, a novel application at the edge of the two afore-mentioned systems (Smart Grid and Smart Home. Such a communication interface has high requirements from functionality, performance and security point of views, given the large amount of distributed connected elements and the real-time information transmission and system management. The paper describes the design and implementation of the data server, Web interface and the embedded networking capabilities of the smart circuit breakers, underlining the protocols and communication technologies used.

  4. Testing of 800 and 1200 kV class circuit breakers

    NARCIS (Netherlands)

    Smeets, R.P.P.; Kuivenhoven, S.; Hofstee, A.B.

    2011-01-01

    The most critical transient a circuit breaker has to endure during its operation is the transient recovery voltage (TRV), initiated by the electric power system as a natural reaction on current interruption. For circuit breakers intended to operate in ultra-high voltage systems (with rated voltage

  5. Appraisal of boundary layer trips for landing gear testing

    Science.gov (United States)

    McCarthy, Philip; Feltham, Graham; Ekmekci, Alis

    2013-11-01

    Dynamic similarity during scaled model testing is difficult to maintain. Forced boundary layer transition via a surface protuberance is a common method used to address this issue, however few guidelines exist for the effective tripping of complex geometries, such as aircraft landing gears. To address this shortcoming, preliminary wind tunnel tests were performed at Re = 500,000. Surface transition visualisation and pressure measurements show that zigzag type trips of a given size and location are effective at promoting transition, thus preventing the formation of laminar separation bubbles and increasing the effective Reynolds number from the critical regime to the supercritical regime. Extension of these experiments to include three additional tripping methods (wires, roughness strips, CADCUT dots) in a range of sizes, at Reynolds number of 200,000 and below, have been performed in a recirculating water channel. Analysis of surface pressure measurements and time resolved PIV for each trip device, size and location has established a set of recommendations for successful use of tripping for future, low Reynolds number landing gear testing.

  6. Training department's role in human factor analysis during post-trip reviews

    International Nuclear Information System (INIS)

    Goodman, D.

    1987-01-01

    Provide training is a frequent corrective action specified in a post-trip review report. This corrective action is most often decided upon by technical and operational staff, not training staff, without a detailed analysis of whether training can resolve the immediate problem or enhance employees' future performance. A more specific human factor or performance problem analysis would often reveal that training cannot impact or resolve the concern to avoid future occurrences. This human factor analysis is similar to Thomas Gilbert's Behavior Engineering Model (Human Competence, McGraw-Hill, 1978) or Robert Mager's/Peter Pipe's Performance Analysis (Analyzing Performance Problems, Pitman Learning, 1984). At Palo Verde Nuclear Generating Station, training analysts participate in post-trip reviews in order to conduct or provide input to this type of human factor and performance problem analysis. Their goal is to keep provide training out of corrective action statements unless training can in fact impact or resolve the problem. The analysts follow a plant specific logic diagram to identify human factors and to identify whether changes to the environment or to the person would best resolve the concern

  7. Statins: antimicrobial resistance breakers or makers?

    Directory of Open Access Journals (Sweden)

    Humphrey H.T. Ko

    2017-10-01

    Full Text Available Introduction The repurposing of non-antibiotic drugs as adjuvant antibiotics may help break antimicrobial resistance (AMR. Statins are commonly prescribed worldwide to lower cholesterol. They also possess qualities of AMR “breakers”, namely direct antibacterial activity, synergism with antibiotics, and ability to stimulate the host immune system. However, statins’ role as AMR breakers may be limited. Their current extensive use for cardiovascular protection might result in selective pressures for resistance, ironically causing statins to be AMR “makers” instead. This review examines statins’ potential as AMR breakers, probable AMR makers, and identifies knowledge gaps in a statin-bacteria-human-environment continuum. The most suitable statin for repurposing is identified, and a mechanism of antibacterial action is postulated based on structure-activity relationship analysis. Methods A literature search using keywords “statin” or “statins” combined with “minimum inhibitory concentration” (MIC was performed in six databases on 7th April 2017. After screening 793 abstracts, 16 relevant studies were identified. Unrelated studies on drug interactions; antifungal or antiviral properties of statins; and antibacterial properties of mevastatin, cerivastatin, antibiotics, or natural products were excluded. Studies involving only statins currently registered for human use were included. Results Against Gram-positive bacteria, simvastatin generally exerted the greatest antibacterial activity (lowest MIC compared to atorvastatin, rosuvastatin, and fluvastatin. Against Gram-negative bacteria, atorvastatin generally exhibited similar or slightly better activity compared to simvastatin, but both were more potent than rosuvastatin and fluvastatin. Discussion Statins may serve as AMR breakers by working synergistically with existing topical antibiotics, attenuating virulence factors, boosting human immunity, or aiding in wound healing. It

  8. Design and computational analysis of passive siphon breaker for 49-2 swimming pool reactor

    International Nuclear Information System (INIS)

    Yue Zhiting; Song Yunpeng; Liu Xingmin; Zou Yao; Wu Yuanyuan

    2014-01-01

    Based on safety considerations, a passive siphon breaker will be added to the primary cooling system of 49-2 Swimming Pool Reactor (SPR). With the breaker location determined, the capability of siphon breakers with diameters of 1.5 cm and 2.0 cm was calculated and analyzed respectively by RELAP5/MOD3.3 code. The results show that in the condition of large break loss of coolant accident these two sizes of siphon breakers are able to break the siphon phenomena, and maintain the pool water level above the reactor core when the reactor and the pump are shutdown. In the end, to be conservative, the siphon breaker with diameter of 2.0 cm is adopted. (authors)

  9. High speed hydraulically-actuated operating system for an electric circuit breaker

    Science.gov (United States)

    Iman, Imdad

    1983-06-07

    This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening.

  10. Interactive effects of relay and circuit breaker aging in a safety-related system

    International Nuclear Information System (INIS)

    Toman, G.J.; Bacanskas, V.P.; Shook, T.A.; Ladlow, C.C.; Gunther, W.

    1987-01-01

    This paper provides an overview of the results of a program to evaluate the aging of circuit breakers and relays and the effects of that aging on the function of a safety system used in nuclear power plants. The program was performed under the Nuclear Plant Aging Research (NPAR) Program of the US Nuclear Regulatory Commission under subcontract to Brookhaven National Laboratory. There were two primary aspects to the program. In the first, the aging and failure modes of relays and circuit breakers were determined by evaluating the construction, design, and materials and the failure data related to nuclear power plant service. In the second, the interactions between a safety system and its relays and circuit breakers were evaluated to determine the effects of relay and circuit breaker aging on the function of the safety system. The aging of relays and circuit breakers was assessed through evaluation of failure data bases, discussions with utility personnel, and evaluation of equipment operating and maintenance manuals. The interaction study was based on an analysis of the safety injection system of a pressurized water reactor. The effects of stresses from the system were analyzed for the tendency to cause deterioration of the relays and circuit breakers in the system. Then the effect of the deterioration of relays and circuit breakers on the functional capability of the safety system was evaluated

  11. [Usefullness of the StoneBreaker lithotripter for percutaneous nephrolithotomy].

    Science.gov (United States)

    del Peso, Almudena Coloma; González, Inmaculada Fernández; Gálvez, Milagros Jiménez; Abad, Pablo Garrido; Fajardo, Gloria Bocardo; Fernández, Luis Miguel Herranz; Arjona, Manuel Fernández; Torres, Lorenzo Herrero; Sanz, Ignacio Pereira

    2008-01-01

    Throughout the history, many devices have been used for breaking urinary tract stones. StoneBreaker (LMA Urology, Gland, Switzerland) is a second generation of intracorporeal lithotripter, pneumatic and portable, which adds several new advantages, like effectiveness in stone fragmentation and easy handling, very useful during percutaneous lithotripsy. We report the case of a 40 year-old male patient, with a left kidney pyelic lithiasis, who was treated by percutaneous lithotripsy, under general anaesthesia, with StoneBreaker (LMA Urology, Gland, Switzerland) as lithotripter. StoneBreaker (LMA Urology, Gland, Switzerland) is a lithotripter usable with rigid and semirigid ureteroscopes, much more powerful than its predecessors. It is able to decrease the number of shocks necessary for stone fragmentation, without bigger tissue reaction. It also has a more comfortable design due to the absence of connections, and its power by replaceable carbon dioxide cartridges.

  12. Low-voltage circuit breaker arcs—simulation and measurements

    International Nuclear Information System (INIS)

    Yang, Fei; Wu, Yi; Rong, Mingzhe; Sun, Hao; Ren, Zhigang; Niu, Chunping; Murphy, Anthony B

    2013-01-01

    As one of the most important electrical components, the low-voltage circuit breaker (LVCB) has been widely used for protection in all types of low-voltage distribution systems. In particular, the low-voltage dc circuit breaker has been arousing great research interest in recent years. In this type of circuit breaker, an air arc is formed in the interrupting process which is a 3D transient arc in a complex chamber geometry with splitter plates. Controlling the arc evolution and the extinction are the most significant problems. This paper reviews published research works referring to LVCB arcs. Based on the working principle, the arcing process is divided into arc commutation, arc motion and arc splitting; we focus our attention on the modelling and measurement of these phases. In addition, previous approaches in papers of the critical physical phenomenon treatment are discussed, such as radiation, metal erosion, wall ablation and turbulence in the air arc. Recommendations for air arc modelling and measurement are presented for further investigation. (topical review)

  13. Megavolt nanosecond generator with semiconductor current breaker

    CERN Document Server

    Bushlyakov, A I; Rukin, S N; Slovikovskij, B G; Timoshenkov, S P

    2002-01-01

    The heavy-current nanosecond generator with the pulse capacity up to 1.6 GW and output voltage of 0.5-1 MW is described. The generator contains four capacity storages, one induction storage and six solid body commutators: one thyristor, four magnetic commutators and a semiconductor current breaker on the SOS-diodes. The results of studies on the energy change-over efficiency through a semiconductor breaker by various external resistance loads as well as the results of the thermal and frequency tests are presented. It is established that selection of the optimal cooling system provides for the generator continuous mode of operation with the pulse sequence frequency from 300 Hz up to 850 Hz

  14. INVESTIGATION OF MECHANICAL STRESSES IN THE DRIVE SHAFT OF MV VACUUM CIRCUIT BREAKER

    Directory of Open Access Journals (Sweden)

    E. I. Baida

    2017-03-01

    Full Text Available Introduction. In the last 10-15 years a dominant position in the market of medium voltage circuit breakers, vacuum circuit breakers have taken in which as an actuator mono- or bistable actuators with permanent magnets are used. Such circuit breakers are characterized by simplicity of design, high reliability, require preventive maintenance for many years. Development, research and improvement of vacuum circuit breakers are carried out at the Department for Electrical Apparatus, National Technical University «Kharkiv Polytechnic Institute». While working on the circuit breakers, developers have to deal with two related objectives – electrical and mechanical. This paper considers the solution of one of these problems – calculation of mechanical forces in the drive shaft of the vacuum circuit breaker in static and dynamic modes. This work was preceded by the failure of the results of measurements of the prototype circuit breakers’ contacts. Measurements have shown that these values do not match the expected values (there were less than the value of 0.8 to 1 mm. The assumption about the reasons for this discrepancy needed to be detailed checked. The results of the work done are presented in this paper. Purpose. Investigation of static and dynamic mechanical stresses and strains in the drive shaft of the vacuum circuit breaker mechanism to determine its characteristics and material selection. Methods. The investigation of mechanical processes is performed by the finite element method in the COMSOL software package. Results. We obtain the static and dynamic characteristics of the circuit breaker drive shaft: deformations, reaction forces, stresses. These characteristics made it possible to determine the actual course of the contacts, select shaft material and calculate the forces acting on the bearings. Conclusions. It is shown that the contact velocity and contact pressure are different from the theoretical value due to the deformation of the

  15. Numaerical simulation of a SF6 circuit-breaker arc

    International Nuclear Information System (INIS)

    Vergne, P.J.; Gonzalez, J.J.; Gleizes, A.

    1995-01-01

    The design and the validation of high-voltage circuit breaker require more and more physical models which take into account complex phenomenae. We present here a numerical simulation of an SF 6 arc established in a simplified geometry of a circuit breaker prototype. Our study deals specially with the turbulent flow, the boundary conditions of the arc roots on the electrodes, the influence of the electromagnetic strengths and the radiative transfer. The results concern a stationary state with fixed geometry and current intensity (I=2000 A)

  16. 735 kV air-blast circuit breakers for Hydro Quebec

    Energy Technology Data Exchange (ETDEWEB)

    Lindstrom, I

    1966-01-01

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

  17. High-voltage direct-current circuit breakers

    International Nuclear Information System (INIS)

    Yoshioka, Y.; Hirasawa, K.

    1991-01-01

    This paper reports that in 1954 the first high-voltage direct-current (HVDC) transmission system was put into operation between Gotland and the mainland of Sweden. Its system voltage and capacity were 100 kV and 20 MW, respectively. Since then many HVDC transmission systems have been planned, constructed, or commissioned in more than 30 places worldwide, and their total capacity is close to 40 GW. Most systems commissioned to date are two-terminal schemes, and HVDC breakers are not yet used in the high-potential main circuit of those systems, because the system is expected to perform well using only converter/inverter control even at a fault stage of the transmission line. However, even in a two-terminal scheme there are not a few merits in using an HVDC breaker when the system has two parallel transmission lines, that is, when it is a double-circuit system

  18. Experiment and CFD simulation of exhaust tube in highvoltage circuit breaker

    Directory of Open Access Journals (Sweden)

    Ye Xiangyang

    2018-01-01

    Full Text Available In a high-voltage circuit breaker, the exhaust tube connects the arc zone with the exhaust volume. During the arc interruption process, the exhaust tube transports the hot gas from the arc interruption zone to the exhaust volume through its distributed holes. The design of a high performance exhaust tube in the circuit breaker development aims for well controlled hot gas evacuation mass flow and pressure waves. In this paper, the exhaust tube behaviour is investigated using Computational Fluid Dynamics (CFD. To verify the CFD simulation, a basic experimental study with pressure measurements at different positions of the exhaust tube is performed. Further, the design parameters influencing the exhaust tube behaviour and circuit breaker performance are investigated and discussed.

  19. Magnetic Method to Characterize the Current Densities in Breaker Arc

    International Nuclear Information System (INIS)

    Machkour, Nadia

    2005-01-01

    The purpose of this research was to use magnetic induction measurements from a low voltage breaker arc, to reconstruct the arc's current density. The measurements were made using Hall effect sensors, which were placed close to, but outside the breaking device. The arc was modelled as a rectangular current sheet, composed of a mix of threadlike current segments and with a current density varying across the propagation direction. We found the magnetic induction of the arc is a convolution product of the current density, and a function depending on the breaker geometry and arc model. Using deconvolution methods, the current density in the electric arc was determined.The method is used to study the arc behavior into the breaker device. Notably, position, arc size, and electric conductivity could all be determined, and then used to characterize the arc mode, diffuse or concentrated, and study the condition of its mode changing

  20. Research on burnout fault of moulded case circuit breaker based on finite element simulation

    Science.gov (United States)

    Xue, Yang; Chang, Shuai; Zhang, Penghe; Xu, Yinghui; Peng, Chuning; Shi, Erwei

    2017-09-01

    In the failure event of molded case circuit breaker, overheating of the molded case near the wiring terminal has a very important proportion. The burnout fault has become an important factor restricting the development of molded case circuit breaker. This paper uses the finite element simulation software to establish the model of molded case circuit breaker by coupling multi-physics field. This model can simulate the operation and study the law of the temperature distribution. The simulation results show that the temperature near the wiring terminal, especially the incoming side of the live wire, of the molded case circuit breaker is much higher than that of the other areas. The steady-state and transient simulation results show that the temperature at the wiring terminals is abnormally increased by increasing the contact resistance of the wiring terminals. This is consistent with the frequent occurrence of burnout of the molded case in this area. Therefore, this paper holds that the burnout failure of the molded case circuit breaker is mainly caused by the abnormal increase of the contact resistance of the wiring terminal.

  1. Optimizing the switching time for 400 kV SF6 circuit breakers

    Science.gov (United States)

    Ciulica, D.

    2018-01-01

    This paper presents real-time voltage and current analysis for optimizing the wave switching point of the circuit breaker SF6. Circuit Breaker plays an important role in power systems. It provides protection for equipment in embedded stations in transport networks. SF6 Circuit Breaker is very important equipment in Power Systems, which is used for up to 400 kV due to its excellent performance. The controlled switching is used to eliminate transient modes and electrodynamic and dielectric charges in the network at manual switching of capacitor, shunt reactors and power transformers. These effects reduce the reliability and lifetime of the equipment installed on the network, or may lead to erroneous protection.

  2. Pengembangan Media Ice Breaker Talking Pen pada Mata Pelajaran PAI Kelas X SMAN 100 Jakarta

    Directory of Open Access Journals (Sweden)

    Ati Sulastri

    2017-07-01

    Full Text Available This study aims to find out how to develop media ice breaker talking pen and media feasibility on the subjects of PAI. The research method used is Borg and Gall development model which includes requirement analysis, validation test, and test phase. The result of this development research is ice breaker talking pen media product which consists of command card and music developed through data collection, planning, product development, and validation and testing. Based on the validation results obtained the average score of the material experts of 4.75 (very good, and from the media experts of 3.78 (good, and the results of student responses about this media amounted to 4.39 or very good category. Therefore the ice breaker talking media on the eyes of learning PAI class X is declared eligible for use with very good category. Keywords: Development Model  Study, Ice Breaker Talking Pen, PAI Abstrak Penelitian ini bertujuan untuk mengetahui cara mengembangkan media ice breaker talking pen dan kelayakan media tersebut pada mata pelajaran PAI. Metode yang digunakan adalah model pengembangan Borg dan Gall yang meliputi analisis kebutuhan, tahap validasi dan tahap uji coba. Hasil penelitian pengembangan ini adalah produk media ice breaker talking pen yang terdiri dari kartu perintah dan musik yang dikembangkan melalui tahap pengumpulan data, perencanaan, pengembangan produk, serta validasi dan uji coba. Berdasarkan pada hasil validasi didapat skor rata-rata dari ahli materi sebesar 4,75 (sangat baik, dan dari ahli media sebesar 3,78 (baik. Serta hasil dari tanggapan siswa mengenai media ini sebesar 4,39 atau kategori sangat baik. Maka dari itu media ice breaker talking pen pada mata pelajaran PAI kelas X dinyatakan layak untuk digunakan dengan kategori sangat baik. Kata Kunci : Pengembangan Model Pembelajaran, Ice Breaker Talking Pen, PAI

  3. Approaching the Processes in the Generator Circuit Breaker at Disconnection through Sustainability Concepts

    Directory of Open Access Journals (Sweden)

    Carmen A. Bulucea

    2013-03-01

    Full Text Available Nowadays, the electric connection circuits of power plants (based on fossil fuels as well as renewable sources entail generator circuit-breakers (GCBs at the generator terminals, since the presence of that electric equipment offers many advantages related to the sustainability of a power plant. In an alternating current (a.c. circuit the interruption of a short circuit is performed by the circuit-breaker at the natural passing through zero of the short-circuit current. During the current interruption, an electric arc is generated between the opened contacts of the circuit-breaker. This arc must be cooled and extinguished in a controlled way. Since the synchronous generator stator can flow via highly asymmetrical short-circuit currents, the phenomena which occur in the case of short-circuit currents interruption determine the main stresses of the generator circuit-breaker; the current interruption requirements of a GCB are significantly higher than for the distribution network circuit breakers. For shedding light on the proper moment when the generator circuit-breaker must operate, using the space phasor of the short-circuit currents, the time expression to the first zero passing of the short-circuit current is determined. Here, the manner is investigated in which various factors influence the delay of the zero passing of the short-circuit current. It is shown that the delay time is influenced by the synchronous machine parameters and by the load conditions which precede the short-circuit. Numerical simulations were conducted of the asymmetrical currents in the case of the sudden three-phase short circuit at the terminals of synchronous generators. Further in this study it is emphasized that although the phenomena produced in the electric arc at the terminals of the circuit-breaker are complicated and not completely explained, the concept of exergy is useful in understanding the physical phenomena. The article points out that just after the short

  4. Primary heat transport pump trip by ground fault (deterioration of insulation in the cable quick disconnect)

    International Nuclear Information System (INIS)

    Chun, C.-Y.

    1991-01-01

    At 08:29 Sept. 1, 1988, Wolsong unit 1 was operating at 100% full power when a primary heat transport pump was suddenly tripped by breaker trip due to ground fault in the power distribution connector assembly. Soon after the pump trip, the reactor was shut down automatically on low heat transport flow. Operators tried to restart the pump twice but failed. A field operator reported to the shift supervisor that he found an electrical spark and smoke at the vicinity of the pump when the pump started to run. Inspection showed that a power distribution connector assembly for making fast and easy power connections to the PHT pump motor, 3312-PM2, was damaged severely by thermal shock. Particularly, broken parts of the insulating plug flew away across the boiler room and dropped to the floor. Direct causes of the failure were bad contact and deterioration of integrity along the creep paths between the insulating plug and the connector housing. The failed connector assembly had been used for more than 7 years. Its status had been checked infrequently during the in-service period. The standard torque value was not applied to the installation of connectors. Therefore, we concluded that long term inservice in combinations of application of improper torque value induced failure of insulation. This paper describes the scenarios, causes of the event and corrective actions to prevent recurrence of this event. (author)

  5. Primary heat transport pump trip by ground fault (deterioration of insulation in the cable quick disconnect)

    Energy Technology Data Exchange (ETDEWEB)

    Chun, C -Y [Wolsong Nuclear Power Plant, Korea Electric Power Corporation, Wolsong (Korea, Republic of)

    1991-04-01

    At 08:29 Sept. 1, 1988, Wolsong unit 1 was operating at 100% full power when a primary heat transport pump was suddenly tripped by breaker trip due to ground fault in the power distribution connector assembly. Soon after the pump trip, the reactor was shut down automatically on low heat transport flow. Operators tried to restart the pump twice but failed. A field operator reported to the shift supervisor that he found an electrical spark and smoke at the vicinity of the pump when the pump started to run. Inspection showed that a power distribution connector assembly for making fast and easy power connections to the PHT pump motor, 3312-PM2, was damaged severely by thermal shock. Particularly, broken parts of the insulating plug flew away across the boiler room and dropped to the floor. Direct causes of the failure were bad contact and deterioration of integrity along the creep paths between the insulating plug and the connector housing. The failed connector assembly had been used for more than 7 years. Its status had been checked infrequently during the in-service period. The standard torque value was not applied to the installation of connectors. Therefore, we concluded that long term inservice in combinations of application of improper torque value induced failure of insulation. This paper describes the scenarios, causes of the event and corrective actions to prevent recurrence of this event. (author)

  6. Experimental and theoretical analysis of vacuum circuit breaker prestrike effect on a transformer

    NARCIS (Netherlands)

    Popov, M.; Smeets, R.P.P.; Van der Sluis, L.; De Herdt, H.; Declerq, J.

    2009-01-01

    The work presented in this paper deals with the investigation of circuit breaker prestrike effect that occurs during energizing a distribution transformer. An experimental test setup that consists of a supply transformer, a vacuum circuit breaker (VCB), a cable and a test transformer is built, and

  7. The testing of generator circuit-breakers

    NARCIS (Netherlands)

    Smeets, R.P.P.; Linden, van der W.A.

    1998-01-01

    Generator circuit-breakers face much higher current and voltage stress than distribution switchgear. This has led to a special standard (ANSI C37.013). Strictly in accordance with this standard's requirements, test circuits and parameters for a 100 kA and 120 kA (25.3 kV) SF6 generator

  8. Life testing of a low voltage air circuit breaker

    International Nuclear Information System (INIS)

    Subudhi, M.

    1991-01-01

    ADS-416 low voltage air circuit breaker manufacture by Westinghouse was mechanically cycled to identify age-related degradation in various breaker subcomponents, in particular, the power-operating mechanism. This accelerated aging test was performed on one breaker unit for over 36,000 cycles. Three separate pole shafts, one with a 60 degree weld, one with a 120 degree weld and one with a 180 degree weld in the third pole lever were used to characterize the cracking in these welds. In addition, during the testing, three different operating mechanisms and several other parts were replaced as they degraded to an inoperable condition. Of the seven welds on the pole shaft, two were found to be the critical ones whose fracture can result in misalignment problems of the pole levers. These failures, in turn can lead to many other problems with the operating mechanism including the burn-out of coils, excessive wear in certain parts and over-stressed linkages. Furthermore, the limiting service life of a number of subcomponents of the power-operated mechanism, including the operating mechanism itself, were assessed. 1 ref., 3 figs

  9. A High Power Solid State Circuit Breaker for Military Hybrid Electric Vehicle Applications

    Science.gov (United States)

    2012-08-01

    the SSCB to isolate a fault, breaker opening is latched and can be reset to reclose the breaker via remote logic input. SSCB state and health...rated load current (125 A). Figure 10 shows that after the SSCB detects a fault and opens, it can also be repeatedly reclosed remotely to attempt to

  10. "I just wanted to get away": An analysis of spring breakers' travel motivations

    Science.gov (United States)

    Nuno F. Ribeiro; Paul E. Durrenberger; Careen M. Yarnal; Garry E. Chick

    2010-01-01

    Scholarly research on Spring Break has grown substantially and has often associated spring breakers' motivations with a number of risky behaviors. Recent research, however, has challenged these assumptions. The purpose of this study was to examine spring breakers' motivations for going on Spring Break. Unlike the media portrayal of Spring Break as a time of...

  11. Research on current sharing of paralleled IGBTs in different DC breaker circuit topologies

    Directory of Open Access Journals (Sweden)

    Chen Ying

    2016-01-01

    Full Text Available IGBT modules used in series and parallel to satisfy the requirement in high-power DC circuit breakers are often prone to large-current destruction due to current unbalance between paralleled IGBTs. It is of great importance to identify the current unbalance causes and to find a method optimizing the current sharing of paralleled IGBTs. In this paper the current-sharing influencing factors are discussed and verified by simulation. Two possible circuit topologies used in DC circuit breakers are proposed and simulated to see their performance in current sharing. The results show that one of them can provide us with a simple and effective method to achieve good current balancing in the DC circuit breaker application.

  12. Metal-clad switchgear with large capacity vacuum circuit breaker in two-tier arrangement for nuclear power plants

    International Nuclear Information System (INIS)

    Yoshikawa, Isao; Watanabe, Hideo; Sugitani, Shinji

    1982-01-01

    Accompanying the increase of main machinery capacity in nuclear power stations, the short-circuit capacity for 6.9 kV in-house auxiliary machinery circuit has increased, and a 63 kA circuit breaker has become necessary. Although magnetic breakers have been used as large capacity breakers so far, vacuum breakers which are more suitable for the recent environmental conditions of power stations have become employed. Hitachi Ltd. has developed the metal-clad switchboard with vacuum breakers of 7.2 kV, 1,200 to 3,000 A, and breaking current of 63 kA in two-tier arrangement. The main features of this breaker are small size, light weight, long life, labour-saving in maintenance and inspection, simple construction, easy handling, high reliability and safety. In addition, in this paper, the construction of the breaker and switchboard, aseismic property, and test results are described. The tests include the withstand voltage test, elevated temperature test, short period current test, short-circuit test, low current breaking test, continuous on-off test, on-off surge combination test and short-circuit breaking test under the condition of vacuum failure in one phase. The aseismic property is guaranteed by analyzing the vibration characteristics and the strength using computer-aided finite element method so that the performance required is satisfied. (Wakatsuki, Y.)

  13. Lessons Learned "Establishing an Electrically Safe Work Condition" Specifically related to Racking Electrical Breakers

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Tommy Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Philbert Roland [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Garcia, Samuel Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-09

    During low voltage electrical equipment maintenance, a bad breaker was identified. The breaker was racked out from the substation cubicle without following the hazardous energy control process identified in the Integrated Work Document (IWD). The IWD required the substation to be in an electrically safe work condition prior to racking the breaker. Per NFPA 70E requirements, electrical equipment shall be put into an electrically safe work condition before an employee performs work on or interacts with equipment in a manner that increases the likelihood of creating an arc flash. Racking in or out a breaker on an energized bus may increase the likelihood of creating an arc flash dependent on equipment conditions. A thorough risk assessment must be performed prior to performing such a task. The risk assessment determines the risk control measures to be put in place prior to performing the work. Electrical Safety Officers (ESO) can assist in performing risk assessments and incorporating risk control measures.

  14. Synchronous transmission circuit breaker development. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Garzon, R D

    1976-08-01

    The need for the development of a synchronous transmission breaker is discussed and the basic preliminary specifications for such a circuit breaker are established and tabulated. The initial exploratory work designed to establish the preferred designs for a synchronous pulse generator, (or current zero predictor), for an operating mechanism and for a suitable interrupter are described in detail. The experimental results obtained with vacuum interrupters and with axial blast interrupters using pure SF/sub 6/, mixtures of SF/sub 6/ and N/sub 2/, and high pressure liquid SF/sub 6/ are reported. The results are then evaluated and the performances obtained with each interrupting media are compared arriving at the end to a choice of a preferred design. This preferred design, an interrupter that uses SF/sub 6/ in the liquid state at pressures of 13.8 megapascals (2000 psi), is completely described. The results obtained in a series of experiments designed to establish limits of performance for this interrupter are also discussed.

  15. NRC Information No. 89-86: Type HK circuit breakers missing close latch anti-shock springs

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    During the recent refueling outage at Fermi Unit 2, the licensee inspected both safety-related and non-safety-related Type HK circuit breakers. The close latch anti-shock springs were observed to be missing in approximately 40 safety-related Type HK circuit breakers that had been manufactured outside of the previously identified timeframes. (The identified circuit breakers were manufactured in 1974.) Thus, the timeframes previously identified by the manufacturer (prior to 1973 and from June 1975 to June 1977) may not be totally inclusive. In addition, because of changes in corporate name, mergers, etc., Type HK circuit breakers may indicate manufacture by ITE, ITE Imperial, Gould, Brown Boveri, or a combination thereof. The current name of the manufacturer is ASEA Brown Boveri. Recipients may need to be cognizant of this when determining whether they utilize potentially affected equipment

  16. 30 CFR 75.601-1 - Short circuit protection; ratings and settings of circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit protection; ratings and settings... Trailing Cables § 75.601-1 Short circuit protection; ratings and settings of circuit breakers. Circuit breakers providing short circuit protection for trailing cables shall be set so as not to exceed the...

  17. Reactor trip on turbine trip inhibit control system for nuclear power generating system

    International Nuclear Information System (INIS)

    Torres, J.M.; Musick, C.R.

    1976-01-01

    A reactor trip on turbine trip inhibit control system for a nuclear power generating system which utilizes steam bypass valves is described. The control system inhibits a normally automatic reactor trip on turbine trip when the bypass valves have the capability of bypassing enough steam to prevent reactor trip limits from being reached and/or to prevent opening of the secondary safety pressure valves. The control system generates a bypass valve capability signal which is continuously compared with the reactor power. If the capability is greater than the reactor power, then an inhibit signal is generated which prevents a turbine trip signal from tripping the nuclear reactor. 10 claims, 4 figures

  18. RF Trip and Beam Loss Diagnostics in LEP using GPS timing

    CERN Document Server

    Arnaudon, L; Beetham, G; Ciapala, Edmond; Juillard, J C; Olsen, R; CERN. Geneva. SPS and LEP Division

    2000-01-01

    A fast diagnostics system has been installed in LEP to allow precise time-stamping of RF unit trips. The system also monitors the fast decay of current when a beam loss occurs. From the information gathered it is now possible to determine which RF units have provoked a beam loss at high energy and which have tripped as a result. The system uses GPS equipment installed at all of the even points of LEP together with fast local DSP acquisition and event recording units in each RF sector. An overall control application driven by the LEPExec arms the system at the start of each fill, calculates and displays RF and trip beam loss events in sequence, then stores the results in a database. The system installation was completed in time for the LEP 2000 startup and initial problems were quickly resolved. Throughout the year it has proved invaluable for high energy running. The experience gained will also be very useful for similar diagnostics applications in LHC.

  19. Numerical simulation for arc-plasma dynamics during contact opening process in electrical circuit-breakers

    International Nuclear Information System (INIS)

    Gupta, D N; Srinivas, D; Patil, G N; Kale, S S; Potnis, S B

    2010-01-01

    The high-energy, high-current thermal plasma that develops between electric contacts in a gas circuit-breaker during circuit interruption is an important phenomenon in the power transmission industry. The high temperature and pressure arc dissipates the tremendous amount of energy generated by the fault current. Simultaneously, this energy has to be transferred away from the contacts to build the dielectric strength level of the circuit-breaker. In order to interrupt the current, the arc must be weakened and finally extinguished. We model these phenomena by using a computer software code based on the solution of the unsteady Euler equations of gas dynamics. We consider the equations of fluid flows. These equations are solved numerically in complex circuit breaker geometries using a finite-volume method. The domain is initially filled with SF 6 gas. We begin our simulations from cold mode, where the fault current is not present (hence no arc). An axis-symmetric geometry of a 145 kV gas circuit-breaker is considered to study the pressure, density, and temperature profile during contact opening process.

  20. Field Trips. Beginnings Workshop.

    Science.gov (United States)

    Cartwright, Sally; Aronson, Susan S.; Stacey, Susan; Winbush, Olga

    2001-01-01

    Five articles highlight benefits and organization of field trips: (1) "Field Trips Promote Child Learning at Its Best"; (2) "Planning for Maximum Benefit, Minimum Risk"; (3) "Coaching Community Hosts"; (4) "The Story of a Field Trip: Trash and Its Place within Children's Learning and Community"; and (5) "Field Trip Stories and Perspectives" (from…

  1. Ohmic heating coil power supply using thyristor circuit breaker in a thermonuclear fusion device

    International Nuclear Information System (INIS)

    Tani, Keiji; Shimada, Ryuichi; Tamura, Sanae; Yabuno, Kohei; Koseki, Shoichiro.

    1982-01-01

    In a large scale Tokamak thermonuclear fusion device such as the critical plasma testing facility (JT60) presently under construction, mechanical breakers such as vacuum and air breakers are mostly used for interrupting DC heavy current which is supplied to the ohmic heating coils of inductive energy accumulation method. The practical use of the DC breakers employing thyristors has just been started because the history of thyristor development is short and thristors are still expensive, in spite of the advantages. In this paper, the circuit is investigated in which the excellent high speed controllability of thyristors is fully utilized, while the economy is taken into accout, and the experiment carried out with a unit model is described. It was found that a thyristor switch, which was constructed by connecting the high speed thyristors of peak off-state voltage rating 2,000 V and mean current rating 500 A in direct parallel, was able to interrupt 12.7 kA current in the power supply circuit of ohmic heating coils developed this time. In addition, the switch configuration was able to be greatly simplified. When the multistage raising of plasma current is required, the raise can be performed with a single thyristor breaker because it can make high speed control. Therefore, the capacity of the breaker can be doubly and drastically reduced. Also, if current unbalance might occur between thyristor switch units, it gives no problem since the time of reverse voltage after current interruption dispersed smaller as current increased. (Wakatsuki, Y.)

  2. Optimal planning of series resistor to control time constant of test circuit for high-voltage AC circuit-breakers

    OpenAIRE

    Yoon-Ho Kim; Jung-Hyeon Ryu; Jin-Hwan Kim; Kern-Joong Kim

    2016-01-01

    The equivalent test circuit that can deliver both short-circuit current and recovery voltage is used to verify the performance of high-voltage circuit breakers. Most of the parameters in this circuit can be obtained by using a simple calculation or a simulation program. The ratings of the circuit breaker include rated short-circuit breaking current, rated short-circuit making current, rated operating sequence of the circuit breaker and rated short-time current. Among these ratings, the short-...

  3. Effect of magnetic attachment with stress breaker on lateral stress to abutment tooth under overdenture.

    Science.gov (United States)

    Gonda, T; Ikebe, K; Ono, T; Nokubi, T

    2004-10-01

    Recently, a newly developed magnetic attachment with stress breaker was used in retentive components in overdentures. Excessive lateral stress has a more harmful effect on natural teeth than axial stress, and the magnetic attachment with stress breaker is expected to reduce lateral forces on abutment teeth and protect it teeth from excessive stress. However, the properties of this retainer have not yet been determined experimentally. This study compares the lateral forces on abutment teeth for three retainers under loading on the denture base in a model study. A mandibular simulation model is constructed to measure lateral stress. Three types of retentive devices are attached to the canine root. These devices include the conventional root coping, the conventional magnetic attachment and the new magnetic attachment with stress breaker. For each retentive device, load is generated on the occlusal table of the model overdenture, and the lateral stress on the canine root and the displacement of the overdenture measured. The magnetic attachment with stress breaker does not displace the denture and exhibits lower lateral stress in the canine root than conventional root coping and magnetic attachments.

  4. Short- circuit tests of circuit breakers

    OpenAIRE

    Chorovský, P.

    2015-01-01

    This paper deals with short-circuit tests of low voltage electrical devices. In the first part of this paper, there are described basic types of short- circuit tests and their principles. Direct and indirect (synthetic) tests with more details are described in the second part. Each test and principles are explained separately. Oscilogram is obtained from short-circuit tests of circuit breakers at laboratory. The aim of this research work is to propose a test circuit for performing indirect test.

  5. Lime helps establish crownvetch on coal-breaker refuse

    Science.gov (United States)

    Miroslaw M. Czapowskyj; Edward A. Sowa

    1976-01-01

    A study was begun in 1965 to determine the effect of lime fertilizer, and mulch on the establishment and growth of crownvetch crowns planted on anthracite coal-breaker refuse. After 7 years the lime application had by far the strongest effect. Both 2.5 and 5.0 tons per acre increased survival and ground cover manyfold, and both treatments were equally beneficial from...

  6. Detusking fence-breaker elephants as an approach in human-elephant conflict mitigation.

    Science.gov (United States)

    Mutinda, Matthew; Chenge, Geoffrey; Gakuya, Francis; Otiende, Moses; Omondi, Patrick; Kasiki, Samuel; Soriguer, Ramón C; Alasaad, Samer

    2014-01-01

    Human-elephant conflict (HEC) is a recurring problem that appears wherever the range of elephants and humans overlap. Different methods including the use of electric fences are used worldwide to mitigate this conflict. Nonetheless, elephants learn quickly that their tusks do not conduct electricity and use them to break down fences (fence-breakers). In Lewa Wildlife Conservancy, Kenya, destructive elephants (Loxodonta africana) were monitored between 2010 and 2013. The fence-breaking rate reached four incidents (fence-breaking) per elephant per 100 days. Ten bull males and 57 females were identified as fence-breakers. The bulls were involved in 85.07% and the females in 14.93% of incidents. The Kenya Wildlife Service approved detusking (partial cutting of tusks) in four of the 10 fence-breakers as a way of preventing them from breaking down fences, thereby mitigating HEC in the Conservancy. The result of the detusking was a drastic six-fold reduction in damage to fences (range: 1.67 to 14.5 times less fence-breaking) by the four worst fence-breaker elephants, because with trimmed tusks elephants lack the tools to break down fences. Detusking could not totally eliminate fence destruction because, despite lacking their tools, elephants can still destroy fences using their heads, bodies and trunks, albeit less effectively. On the other hand, apart from inherent aesthetic considerations, the detusking of elephants may have certain negative effects on factors such as elephants' social hierarchies, breeding, mate selection and their access to essential minerals and food. Elephant detusking seems to be effective in drastically reducing fence-breaking incidents, nonetheless its negative effects on behaviour, access to food and its aesthetical consequences still need to be further studied and investigated.

  7. Detusking fence-breaker elephants as an approach in human-elephant conflict mitigation.

    Directory of Open Access Journals (Sweden)

    Matthew Mutinda

    Full Text Available Human-elephant conflict (HEC is a recurring problem that appears wherever the range of elephants and humans overlap. Different methods including the use of electric fences are used worldwide to mitigate this conflict. Nonetheless, elephants learn quickly that their tusks do not conduct electricity and use them to break down fences (fence-breakers.In Lewa Wildlife Conservancy, Kenya, destructive elephants (Loxodonta africana were monitored between 2010 and 2013. The fence-breaking rate reached four incidents (fence-breaking per elephant per 100 days. Ten bull males and 57 females were identified as fence-breakers. The bulls were involved in 85.07% and the females in 14.93% of incidents. The Kenya Wildlife Service approved detusking (partial cutting of tusks in four of the 10 fence-breakers as a way of preventing them from breaking down fences, thereby mitigating HEC in the Conservancy. The result of the detusking was a drastic six-fold reduction in damage to fences (range: 1.67 to 14.5 times less fence-breaking by the four worst fence-breaker elephants, because with trimmed tusks elephants lack the tools to break down fences. Detusking could not totally eliminate fence destruction because, despite lacking their tools, elephants can still destroy fences using their heads, bodies and trunks, albeit less effectively. On the other hand, apart from inherent aesthetic considerations, the detusking of elephants may have certain negative effects on factors such as elephants' social hierarchies, breeding, mate selection and their access to essential minerals and food.Elephant detusking seems to be effective in drastically reducing fence-breaking incidents, nonetheless its negative effects on behaviour, access to food and its aesthetical consequences still need to be further studied and investigated.

  8. The Effect of Current-Limiting Reactors on the Tripping of Short Circuits in High-Voltage Electrical Equipment

    International Nuclear Information System (INIS)

    Volkov, M. S.; Gusev, Yu. P.; Monakov, Yu. V.; Cho, Gvan Chun

    2016-01-01

    The insertion of current-limiting reactors into electrical equipment operating at a voltage of 110 and 220 kV produces a change in the parameters of the transient recovery voltages at the contacts of the circuit breakers for disconnecting short circuits, which could be the reason for the increase in the duration of the short circuit, damage to the electrical equipment and losses in the power system. The results of mathematical modeling of the transients, caused by tripping of the short circuit in a reactive electric power transmission line are presented, and data are given on the negative effect of a current-limiting resistor on the rate of increase and peak value of the transient recovery voltages. Methods of ensuring the standard requirements imposed on the parameters of the transient recovery voltages when using current-limiting reactors in the high-voltage electrical equipment of power plants and substations are proposed and analyzed

  9. Test model of the fast thyristor circuit breaker, for TORE SUPRA

    International Nuclear Information System (INIS)

    Bareyt, B.; Leloup, C.; Rijnoudt, E.

    1984-01-01

    The tokamak TORE SUPRA, permits, owing to the toroidal superconducting coils and to the poloidal field system performances, long discharges (30 s and more), for a plasma current of typically 2 MA. The poloidal field system uses the magnetic energy initially stored, for the ignition and the fast rise of the plasma current, by forcing the primary current to flow through a resistor after breaking the main rectifier current by a fast thyristor circuit breaker. In order to test the technical capabilities of such a breaker system made of fast thyristors, in series and in parallel, after a single thyristor test model T1 the series arrangement was studied on a 24 thyristor test model T2 and the parallel arrangement problems, led the manufacturer CGEE Alsthom, to build a new test model T3. (author)

  10. Thyristor based short circuit current injection in isolated grids

    OpenAIRE

    Hoff, Bjarte; Sharma, Pawan; Østrem, Trond

    2017-01-01

    This paper proposes a thyristor based short circuit current injector for providing short circuit current in isolated and weak grids, where sufficient fault current to trigger circuit breakers may not be available. This will allow the use of conventional miniature circuit breakers, which requires high fault current for instantaneous tripping. The method has been validated through experiments.

  11. TRIP RATES FOR CONDOMINIUM CONSTRUCTION PROJECT

    Directory of Open Access Journals (Sweden)

    Wirach Hirun

    2015-01-01

    Full Text Available The number of large scale condominium construction projects had dramatically increased in Bangkok. Many projects had occurred in either densely populated areas or in central business districts, where traffic conditions were usually highly congested. To prevent traffic problems, a traffic impact study must be prepared and submitted for review by concerned public authorities. Unit trip generation rates were important data in traffic impact analysis. Without accurate unit trip generation rates, public agencies could not obtain accurate information on the traffic that will be generated. This study aimed to study trip rates and the factors affecting them for condominium construction project in Bangkok. The data were collected from 30 condominium construction sites located in 15 districts of Bangkok. The analysis used the linear regression method and was divided into three cases: 1 trip rates for all vehicles, 2 trip rates for classified vehicles, and 3 trip rates for all types of condominium. All case analyses considered weekdays, Saturday, and Sunday. The results found that trip rates related to the number of dwellings in the condominium. The trip rates for all vehicle types on weekdays, Saturday, and Sunday were 10.636, 4.647, and 9.294 vehicles per 100 dwelling units per day respectively. The trip rates for six-wheeled and ten-wheeled trucks on weekdays, Saturday, and Sunday were 2.046, 0.975, and 0.575 vehicles per 100 dwelling units per day respectively. The trip rate for four-wheeled trucks and passenger cars on weekdays was 1.960. Regarding condominium types, the trip rate for low rise condominiums for all vehicle types on weekdays was 5.315 while the trip rates for high rise condominiums for weekdays, Saturday, and Sunday were 3.965, 2.667, and 1.261 respectively.

  12. 30 CFR 75.800-2 - Approved circuit schemes.

    Science.gov (United States)

    2010-07-01

    ... undervoltage protection if the relay coils are designed to trip the circuit breaker when line voltage decreases to 40 percent to 60 percent of the nominal line voltage; (b) Ground trip relays on resistance... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution...

  13. A thyristor breaker of 1.5 109 V.A. for the poloidal field system of TORUS SUPRA

    International Nuclear Information System (INIS)

    Bareyt, B.; Leloup, C.; Rijnoudt, E.

    1980-09-01

    The poloidal field system of Torus Supra has an inductive storage of approximately 38 MJ, which has conducted to research the best solution for a D.C. breaker (55 kA., 27 kV). A solid-state breaker has been chosen. The working principles have been tested on a small size model. The final circuit breaker will contain a large number of thyristors in series and in parallel; the critical problem lies in the series arrangement. A test unit for full tension has been constructed. In this unit the thyristors are submitted to the maximum current as well as to the maximum voltage. The surges measured during tests are not higher than the calculated values. A synthetic circuit of the poloidal field system has been used for test under the final working conditions

  14. The life test of a DC circuit breaker of tokamak device JT-60 for a nuclear fusion research

    International Nuclear Information System (INIS)

    Shimada, Ryuichi; Tani, Keiji; Kishimoto, Hiroshi; Tamura, Sanae; Yanabu, Satoru.

    1979-01-01

    In the Tokamak devices for nuclear fusion research, the construction of the current transformer circuits having plasma as the secondary circuit and the change of the primary circuit current are necessary for generating current in the plasma. This is considered to be fairly difficult in practice if conventional methods using capacitor discharge and iron core coils are employed. Considering such circumstances, it was decided for JT-60 to use an air-core current transformer coil and to employ the method of storing energy in the form of current in the coil inductance instead of a capacitor. For this reason, a DC circuit breaker is required to interrupt coil current. The authors improved an AV vacuum breaker, which had been developed as the vacuum breaker of longitudinal magnetic field type applying a magnetic field in parallel with an arc, to get the one for DC circuit for the purpose of applying it to JT-60. In this paper, the operational characteristic of the DC breaker is described, the construction and function of the life test circuit is explained, and the test results are reported. Finally, interruptions of 10,000 times at 20 kA were carried out. It is successful that the restrike of arc occurring during tens of milli-seconds after interruptions was improved to 0.05% or less for 10,000 times operations. Further, it was found that the generation of arc restrike can be reduced practically to zero with two breakers in series. (Wakatsuki, Y.)

  15. The Solenarc circuit-breaker of high performance level

    International Nuclear Information System (INIS)

    Lehmann, J.M.

    1983-01-01

    After recalling the breaking principle involved in MV circuit-breakers manufactured by Merlin Gerin, it is showed how Solenarc technique enables specific problems to be solved that are set by the equipment of Eurodif plant at Tricastin and that represent constraints similar to those encountered with protective equipment for power station auxiliaries (high rated currents, long duration overloads, very high short-circuit currents, current breaks without natural passage through zero, etc.) [fr

  16. Healthy Ride Trip Data

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A dataset that shows trips taken using the Healthy Ride system by quarter. The dataset includes bike number, membership type, trip start and end timestamp, and...

  17. Current-zero measurements of vacuum circuit breakers interrupting short-line faults

    NARCIS (Netherlands)

    Smeets, R.P.P.; Linden, van der W.A.

    2003-01-01

    Current zero measurements are performed during short-line fault interruption tests of vacuum circuit breakers. This switching cycle is characterized by a very steep transient recovery voltage. High-resolution measurements of near current-zero arc current and voltage were carried out. Various

  18. Nuclear reactor trip system

    International Nuclear Information System (INIS)

    Cook, B.M.

    1982-01-01

    Each parameter of the processes of a nuclear reactor and components operatively associated with it is monitored by a set of four like sensors. A trip system normally operates on a ''two out four'' configuration; i.e., to trip the reactor it is necessary that at least two sensors of a set sense an off-normal parameter. This assumes that all sensors are in normal operating condition. However, when a sensor is in test or is subject to maintenance or is defective or disabled, the ''two out of four''configuration would be reduced to a ''one out of three'' configuration because the affected sensor is taken out of service. This would expose the system to the possibility that a single sensor failure, which may be spurious, will cause a trip of the reactor. To prevent this, it is necessary that the affected sensor be bypassed. If only one sensor is bypassed, the system operates on a ''two out of three'' configuration. With two sensors bypassed, the sensing of an off-normal parameter by a third sensor trips the reactor. The by-pass circuit also disables the circuit coupling the by-passed sensor to the trip circuit. (author)

  19. Fuzzy Diagnostic System for Oleo-Pneumatic Drive Mechanism of High-Voltage Circuit Breakers

    Directory of Open Access Journals (Sweden)

    Viorel Nicolau

    2013-01-01

    Full Text Available Many oil-based high-voltage circuit breakers are still in use in national power networks of developing countries, like those in Eastern Europe. Changing these breakers with new more reliable ones is not an easy task, due to their implementing costs. The acting device, called oleo-pneumatic mechanism (MOP, presents the highest fault rate from all components of circuit breaker. Therefore, online predictive diagnosis and early detection of the MOP fault tendencies are very important for their good functioning state. In this paper, fuzzy logic approach is used for the diagnosis of MOP-type drive mechanisms. Expert rules are generated to estimate the MOP functioning state, and a fuzzy system is proposed for predictive diagnosis. The fuzzy inputs give information about the number of starts and time of functioning per hour, in terms of short-term components, and their mean values. Several fuzzy systems were generated, using different sets of membership functions and rule bases, and their output performances are studied. Simulation results are presented based on an input data set, which contains hourly records of operating points for a time horizon of five years. The fuzzy systems work well, making an early detection of the MOP fault tendencies.

  20. Experimental and theoretical analysis of vacuum circuit breaker prestrike effect on a transformer, Calgary Alberta, Canada 29-31 July 2009

    NARCIS (Netherlands)

    Popov, M.; Smeets, R.P.P.; Sluis, van der L.; Herdt, de H.; Declercq, J.

    2009-01-01

    Summary form only given. The work presented in this paper deals with the investigation of circuit breaker prestrike effect that occurs during energizing a distribution transformer. An experimental test setup that consists of a supply transformer, a vacuum circuit breaker (VCB), a cable and a test

  1. 735 kV circuit breakers for ehv

    Energy Technology Data Exchange (ETDEWEB)

    1966-01-01

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

  2. Technical-economic evaluation of the utilization of closing resistor in CEMIG extra-high voltage circuit breakers

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Angelica C.O.; Pinto, Roberto del Giudice R.; Teixeira, Jose Cleber; Fonseca, Rodrigo Assuncao; F, Junior, Sebastiao V [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)

    1994-12-31

    This paper presents the technical and economic studies performed by CEMIG, Companhia Energetica de Minas Gerais, Brazil, concerning the use of closing resistor in its extra-high voltage (EHV) breakers. The analysis emphasizes the advantages which could be achieved with the elimination of the resistor as far as costs and reliability are concerned. This evaluation was motivated by two 500 kV breaker failures resulting from the breakdown of the closing resistor operation mechanism. These occurrences resulted in operative restriction for CEMIG EHV system. The analysis demanded a review of the capability criteria of silicon carbide (Si C) gap arresters, which are still greatly used in CEMIG EHV System, and of the procedures to be applied when carrying out the transient studies. The investigation resulted in the prompt removal of closing resistors from circuit breakers in CEMIG extra-high voltage system generating an economy of approximately U$ 840,00 and an improvement in safety and system reliability. (author) 13 refs., 4 figs., 1 tab.

  3. Film breakers prevent migration of aqueous potassium hydroxide in fuel cells

    Science.gov (United States)

    Hess, P. D.

    1970-01-01

    Electrolyte film breakers made from polytetrafluoroethylene are installed in the reactant and water vapor removal outlets of each cell and sealed by elastomers. Use of these devices in the water vapor removal cavity outlets prevents loss of KOH solution through film migration during water removal.

  4. Trip internalization in multi-use developments.

    Science.gov (United States)

    2014-04-01

    Internal trip capture refers to how the number trips to and from a development are reduced by the proximity of : complementary land uses within the development (e.g., residential to retail). Internal trips occur within the : development and do not en...

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

    International Nuclear Information System (INIS)

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

    1992-01-01

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

  6. A Novel Approach to Power Circuit Breaker Design for Replacement of SF6

    Directory of Open Access Journals (Sweden)

    D. J. Telfer

    2004-01-01

    Full Text Available This contribution explores the role of PTFE ablation in enhancing current interruption for various background gases in high voltage circuit breakers. An assessment of the current interruption capability has been made in terms of the arcing duration and the contact gap length at which critical arc extinction is achieved. These observations are supported by measurements of the magnitude of extinction and re-ignition voltage peaks. Most previous and other current experimental work on gas filled circuit breaker design follows conventional wisdom in investigating arcing behaviours at elevated gas pressures (usually up to 6 bar. But in this work we concentrate on the effects of using low gas pressures (less than 1 bar in the presence of a close-fitting shield of ablatant polymer material (PTFE that surrounds the electrode assembly of an experimental high power circuit breaker. We demonstrate that for several different gases, arc extinction capability compares well under these conditions with SF6, suggesting that SF6 could be replaced entirely in this novel system by more environmentally friendly gases. Moreover, the critical contact gap lengths at extinction are only slightly greater than when using SF6 at 6 bar. Weight loss measurements from the ablatant shield suggest that a chemical puffer action is the most likely mechanism for achieving the observed arc extinctions in this system.

  7. Power supply trip control for nuclear reactor

    International Nuclear Information System (INIS)

    Hager, R.E.; Gutman, Jerzy.

    1987-01-01

    A control system for a trip coil in a switchgear mechanism controls the supply of electrical power to a process control device and ensures de-energization of the trip coil shortly after the trip coil is energized. The trip coil is energized not by an independent dc source as in prior art, but from rectified power from a step down transformer supplied from the switchgear output side. The transformer feeds a rectifier which is connected to the trip coil via a trip activation device. The output of the rectifier can be monitored using an optical converter to determine the ability of the control system to activate the trip coil and the condition of the power supplied to the process control device. The control device may be a rod positioner in a pressurised water nuclear reactor. (author)

  8. Effect of Circuit Breaker Shunt Resistance on Chaotic Ferroresonance in Voltage Transformer

    Directory of Open Access Journals (Sweden)

    RADMANESH, H.

    2010-08-01

    Full Text Available Ferroresonance or nonlinear resonance is a complex electrical phenomenon, which may cause over voltages and over currents in the electrical power system which endangers the system reliability and continuous safe operating. This paper studies the effect of circuit breaker shunt resistance on the control of chaotic ferroresonance in a voltage transformer. It is expected that this resistance generally can cause ferroresonance dropout. For confirmation this aspect Simulation has been done on a one phase voltage transformer rated 100VA, 275kV. The magnetization characteristic of the transformer is modeled by a single-value two-term polynomial with q=7. The simulation results reveal that considering the shunt resistance on the circuit breaker, exhibits a great mitigating effect on ferroresonance over voltages. Significant effect on the onset of chaos, the range of parameter values that may lead to chaos along with ferroresonance voltages has been obtained and presented.

  9. Probabilistic methods in a study of trip setpoints

    International Nuclear Information System (INIS)

    Kaulitz, D. E.

    2012-01-01

    Most early vintage Boiling Water Reactors have a high head and high capacity High Pressure Coolant Injection (HPCI) pump to keep the core covered following a loss of coolant accident (LOCA). However, the protection afforded by the HPCI pump for mitigating a LOCA introduces the potential that a spurious start of the HPCI pump could oversupply the reactor vessel and lead to an automatic trip of the main turbine due to high water level. A turbine trip and associated increase in moderator density could challenge the bases of fuel integrity operating limits. To prevent turbine trip during spurious operation of the HPCI pump, the reactor protection system includes instrumentation and logic to sense high water level and automatically trip the HPCI pump prior to reaching the turbine trip setpoint. This paper describes an analysis that was performed to determine if existing reactor vessel water level trip instrumentation, logic and setpoints result in a high probability that the HPCI pump will trip prior to actuation of the turbine trip. Using nominal values for the initial water level and for the HPCI pump and turbine trip setpoints, and using the probability distribution functions for measurement uncertainty in these setpoints, a Monte Carlo simulation was employed to determine probabilities of successfully tripping the HPCI pump prior to tripping of the turbine. The results of the analysis established that the existing setpoints, instrumentation and logic would be expected to reliably prevent a trip of the main turbine. (authors)

  10. Guam Commercial Purchases (Trip Ticket)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — DAWR collects Trip Ticket or purchase invoice data from vendors that buy fish directly from the fishermen. Similar to the trip ticket system in Saipan, this is a...

  11. Breaker Maintenance: Volume 3, Molded-Case circuit breakers

    International Nuclear Information System (INIS)

    Davis, E.L.; Funk, D.L.

    1991-09-01

    Modeled-case circuit breakers (MCCBs) provide power and circuit protection in nuclear plant electrical distribution systems. Thus, their proper operation is essential to the safe and reliable operation of plant electrical distribution systems. This guide for both nuclear and non-nuclear power generating facilities will help improve the maintenance and reliability of MCCBs. The authors developed this guide to establish a working-level understanding of hardware performance trends, reliability, and failure modes from which maintenance practices could be specified. The first step in preparing this guide was an in-depth review of available operating experience and failure data, which was obtained from nuclear information sources such as EPRI's Nuclear Maintenance Applications Center. In addition, they evaluated some nonnuclear reliability data. Next, they investigated current industry practices, including a review of manufacturer's recommendations and numerous industry standards. Finally, they used the collective information to develop programmatic recommendations and, where appropriate, detailed inspection and test guidance. This guide offers many recommendations applicable to MCCB maintenance, such as an engineering description of MCCBs and their operation; an overview of reliability and failure data; programmatic recommendations, including inspection and test periodicity; detailed inspection and test guidance; and corrective maintenance recommendations. Supplementary information includes an overview of industry standards, a discussion of regulatory issues, and sample data sheets. An evaluation of operating experience indicates that a maintenance program need not be overly complicated to detect the predominant failure modes associated with MCCBs. Those implementating an MCCB maintenance and testing program, however, must recognize the inherent limitations associated with field-testing of these devices. 42 refs., 17 figs., 7 tabs

  12. Reevaluation of steam generator level trip set point

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Yoon Sub; Soh, Dong Sub; Kim, Sung Oh; Jung, Se Won; Sung, Kang Sik; Lee, Joon [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-06-01

    The reactor trip by the low level of steam generator water accounts for a substantial portion of reactor scrams in a nuclear plant and the feasibility of modification of the steam generator water level trip system of YGN 1/2 was evaluated in this study. The study revealed removal of the reactor trip function from the SG water level trip system is not possible because of plant safety but relaxation of the trip set point by 9 % is feasible. The set point relaxation requires drilling of new holes for level measurement to operating steam generators. Characteristics of negative neutron flux rate trip and reactor trip were also reviewed as an additional work. Since the purpose of the trip system modification for reduction of a reactor scram frequency is not to satisfy legal requirements but to improve plant performance and the modification yields positive and negative aspects, the decision of actual modification needs to be made based on the results of this study and also the policy of a plant owner. 37 figs, 6 tabs, 14 refs. (Author).

  13. Vacuum circuit breaker postarc current modelling based on the theory of Langmuir probes

    NARCIS (Netherlands)

    Lanen, van E.P.A.; Smeets, R.; Popov, M.; Sluis, van der L.

    2007-01-01

    High-resolution measurements on the postarc current in vacuum circuit breakers (VCBs) reveal a period, immediately following current-zero, in which the voltage remains practically zero. The most widely used model for simulating the interaction between the postarc current with the electrical circuit

  14. Estimation of expected short-circuit current levels in and circuit-breaker requirements for the 330 to 750 kV networks of the southern integrated power grid

    Energy Technology Data Exchange (ETDEWEB)

    Krivushkin, L.F.; Gorazeeva, T.F.

    1978-08-01

    Studies were made in order to project the operating levels in the Southern Integrated Power Grid to the year 2000. The short-circuit current levels and, the requirements which circuit breakers will have to meet are estimated. A gradual transition from 330 to 750 kV generation is foreseen, with 330 kV networks remaining only for a purely distribution service. The number of 330 kV line hookups and the number of circuit breakers at nodal points (stations and substations) will not change significantly, they will account for 40% of all circuit breakers installed in 25% of all nodal points. Short-circuit currents are expected to reach the 46 kA level in 750 kV networks and 63 kA (standing wave voltage 1.5 to 2.5 kV/microsecond) in 330 kV networks. These are the ratings of circuit breakers; of the 63 kA ones 150 will be needed by 1980--1990 and 400 by 1990--2000. It will also be eventually worthwhile to install circuit breakers with a 63 kA-750 kV rating.

  15. ICARUS trip

    CERN Document Server

    Caraban Gonzalez, Noemi

    2017-01-01

    It’s lived in two different countries and is about to make its way to a third. It’s the largest machine of its kind, designed to find extremely elusive particles and tell us more about them. Its pioneering technology is the blueprint for some of the most advanced science experiments in the world. And this summer, it will travel across the Atlantic Ocean to its new home (and its new mission) at the U.S. Department of Energy’s Fermi National Accelerator Laboratory. It’s called ICARUS, and you can follow its journey over land and sea with the help of an interactive map at IcarusTrip.fnal.gov (link is external), or on Facebook (link is external), Twitter (link is external) and Instagram (link is external) using the hashtag #IcarusTrip.

  16. Procedural Aspects of Compulsory Licensing Under TRIPS

    DEFF Research Database (Denmark)

    Wested, Jakob; Minssen, Timo

    2017-01-01

    and discussion addressed the framework and context for CL provided by the TRIPS convention. Both the specific requirements enshrined in TRIPS art 31 and the broader objectives and principles enshrined in TRIPS, e.g. transfer and dissemination of technology (art 7), protection of public health (art 8......In 2013, Indian authorities granted a compulsory license to NATCO Pharmaceuticals for a patented pharmaceutical product sold by Bayer. This decision raised several complex issues regarding the grant a CL and their consistency with the principles and objectives of TRIPS. Furthermore, in January 2017...

  17. The return trip is felt shorter only postdictively: A psychophysiological study of the return trip effect [corrected].

    Directory of Open Access Journals (Sweden)

    Ryosuke Ozawa

    Full Text Available The return trip often seems shorter than the outward trip even when the distance and actual time are identical. To date, studies on the return trip effect have failed to confirm its existence in a situation that is ecologically valid in terms of environment and duration. In addition, physiological influences as part of fundamental timing mechanisms in daily activities have not been investigated in the time perception literature. The present study compared round-trip and non-round-trip conditions in an ecological situation. Time estimation in real time and postdictive estimation were used to clarify the situations where the return trip effect occurs. Autonomic nervous system activity was evaluated from the electrocardiogram using the Lorenz plot to demonstrate the relationship between time perception and physiological indices. The results suggest that the return trip effect is caused only postdictively. Electrocardiographic analysis revealed that the two experimental conditions induced different responses in the autonomic nervous system, particularly in sympathetic nervous function, and that parasympathetic function correlated with postdictive timing. To account for the main findings, the discrepancy between the two time estimates is discussed in the light of timing strategies, i.e., prospective and retrospective timing, which reflect different emphasis on attention and memory processes. Also each timing method, i.e., the verbal estimation, production or comparative judgment, has different characteristics such as the quantification of duration in time units or knowledge of the target duration, which may be responsible for the discrepancy. The relationship between postdictive time estimation and the parasympathetic nervous system is also discussed.

  18. Time coordination of heterogeneous distance protections using a domain specific language

    OpenAIRE

    Marcin Kowalski; Jan Magott

    2012-01-01

    BACKGROUND: Distance protections are widely used in protection of energy transmission lines, but their time coordination is still an important and difficult problem. Inappropriate configuration leads to a hazard event: remote circuit breaker tripping provided the local circuit breaker can be opened, which severely impairs power system operation.OBJECTIVE: To describe a method and provide software tools to alleviate the hazard in power systems.METHODS: A domain specific language (DSL) for repr...

  19. Improving plant availability by predicting reactor trips

    International Nuclear Information System (INIS)

    Frank, M.V.; Epstein, S.A.

    1986-01-01

    Management Ahnalysis Company (MAC) has developed and applied two complementary software packages called RiTSE and RAMSES. Together they provide an mini-computer workstation for maintenance and operations personnel to dramatically reduce inadvertent reactor trips. They are intended to be used by those responsible at the plant for authorizing work during operation (such as a clearance coordinator or shift foreman in U.S. plants). They discover and represent all components, processes, and their interactions that could case a trip. They predict if future activities at the plant would cause a reactor trip, provide a reactor trip warning system and aid in post-trip cause analysis. RAMSES is a general reliability engineering software package that uses concepts of artificial intelligence to provide unique capabilities on personal and mini-computers

  20. Self-commutated high-voltage direct current transmission with DC circuit breakers. Backbone for the energy policy turnaround; Selbstgefuehrte Hochspannungs-Gleichstromuebertragung mit DC-Leistungsschalter. Rueckgrat fuer die Energiewende

    Energy Technology Data Exchange (ETDEWEB)

    Goerner, Raphael [ABB AG, Mannheim (Germany). Marketing und Vertrieb, Geschaeftsbereich Grid Systems

    2013-06-01

    The 'current war' between direct current and alternating current is extended by a new location. In the future, both technologies work together in order to provide a reliable power transmission in Germany and long-term in Europe. This is based on the self-guided high-voltage direct current transmission. In conjunction with direct current circuit breakers (DC circuit breaker) the power circuit breakers may help to make the transmission grids more flexible and to minimize losses.

  1. Function and operation of the Doublet III E-coil vacuum breaker system

    International Nuclear Information System (INIS)

    Callis, R.W.; Jackson, G.; DeGrassie, J.; Peterson, P.; LeVine, F.

    1979-11-01

    The ohmic heating system for the Doublet III fusion research device at General Atomic is required to provide the voltage for the initial breakdown phase (there is no preionization) along with the energy to drive the plasma current to a value of 2.5 MA or greater. This requires a peak one turn voltage of 250 volts (16 kV across coil terminals) and a magnetic flux swing of 5 volt-seconds (peak coil current of 110 kA). This voltage and flux swing is accomplished by reverse biasing the ohmic heating coil (E-coil) where, upon reaching a value of 110 ka the coil current is interrupted and commutated into a RC network producing 16 kV across the coil. The interrruption of the E-coil current is accomplished by the use of an array of vacuum circuit breakers (VCB's) and a counter plus network. A description is given of the ohmic heating circuit and the performance of the vacuum circuit breaker array and its counter pulse system

  2. Hydraulically-actuated operating system for an electric circuit breaker

    Science.gov (United States)

    Barkan, Philip; Imam, Imdad

    1978-01-01

    This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A vent is located hydraulically between the actuating space and the valve for affording communication between said actuating space and a low pressure region. Flow control means is provided for restricting leakage through said vent to a rate that prevents said leakage from substantially detracting from the development of pressure within said actuatng space during the period from initial opening of the valve to the time when said piston has moved through most of its opening stroke. Following such period and while the valve is still open, said flow control means allows effective leakage through said vent. The accumulator has a limited capacity that results in the pressure within said actuating space decaying promptly to a low value as a result of effective leakage through said vent after the piston has moved through a circuit-breaker opening stroke and while the valve is in its open state. Means is provided for resetting the valve to its closed state in response to said pressure decay in the actuating space.

  3. Trip generation and data analysis study.

    Science.gov (United States)

    2015-09-01

    Through the Trip Generation and Data Analysis Study, the District of Columbia Department of : Transportation (DDOT) is undertaking research to better understand multimodal urban trip generation : at mixed-use sites in the District. The study is helpi...

  4. Trip generation characteristics of special generators

    Science.gov (United States)

    2010-03-01

    Special generators are introduced in the sequential four-step modeling procedure to represent certain types of facilities whose trip generation characteristics are not fully captured by the standard trip generation module. They are also used in the t...

  5. Breaker turbulence and sediment suspension in the surf zone

    DEFF Research Database (Denmark)

    Aagaard, Troels; Hughes, Michael G

    2010-01-01

    Field measurements of fluid velocities and suspended sediment concentrations were used to investigate the relative role of coherent vortices (related to wave breaking) in suspended sediment dynamics. The measurements were obtained from a barred (intermediate-type) beach and the instrument rig...... and incoherent higher-frequency turbulence using a threshold magnitude for the vertical velocity component. Plunging breakers displayed the largest root-mean-square (RMS) and maximum vertical velocities; the latter reaching approximately 1 m s(-1). These measurements were made at an elevation of 0.15 m above...

  6. Effects of magnetic core geometry on false detection in residual current sensor

    International Nuclear Information System (INIS)

    Colin, Bruno; Chillet, Christian; Kedous-Lebouc, Afef; Mas, Patrick

    2006-01-01

    Under high-supply current, residual circuit breakers are subject to abnormal tripping, caused by false residual currents. Geometric or magnetic anomalies in the circuit breaker ring core seem to be responsible for these abnormal currents. This paper studies a few anomalies (spiral shape effect, conductor eccentricity, lamination effect) and calculates different contributions using the finite element simulations. The results show that the ring core, made of thin wound magnetic tape, is particularly sensitive to primary conductor eccentricity

  7. Field Trips as Valuable Learning Experiences in Geography Courses

    Science.gov (United States)

    Krakowka, Amy Richmond

    2012-01-01

    Field trips have been acknowledged as valuable learning experiences in geography. This article uses Kolb's (1984) experiential learning model to discuss how students learn and how field trips can help enhance learning. Using Kolb's experiential learning theory as a guide in the design of field trips helps ensure that field trips contribute to…

  8. Fellows in the Middle: Fabulous Field Trips

    Science.gov (United States)

    West, Mary Lou

    2008-05-01

    Montclair State University's NSF GK-12 Program focuses on grades 7 and 8 in five urban public school districts in northern New Jersey. Each year four fieldtrips are taken by the students, middle school teachers, and graduate student Fellows. Many interdisciplinary hands-on lessons are written for use before, during and after each trip with this year's theme of Earth history. The Sterling Hill Mine trip evoked lessons on geology, economics, crystal structure, density, and pH. A virtual trip (webcam link) to scientists in the rainforest of Panama prompted critical thinking, categorizing layers and animals, and construction of model food webs. In the field trip to the NJ School of Conservation the students will build model aquifers, measure tree heights, and measure stream flow to compare to their Hackensack River. Finally the students will travel to MSU for a Math/Science Day with research talks, lab tours, hands-on activities, and a poster session. In January 2008 seventeen teachers, Fellows, and grant personnel took a field trip to China to set up collaborations with researchers and schools in Beijing and Xi'an, including the Beijing Ancient Observatory. All field trips are fabulous! Next year (IYA) our theme will be planetary science and will feature field trips to the Newark Museum's Dreyfuss Planetarium, BCC Buehler Challenger & Science Center, and star parties. We look forward to invigorating middle school science and mathematics with exciting astronomy. Funded by NSF #0638708

  9. Expert system for the CPCS-initiated trip analysis

    International Nuclear Information System (INIS)

    Sohn, Sedo; Im, Inyoung; Kuh, Jungeui

    1991-01-01

    In Yonggwang nuclear units 3 and 4, the core protection calculator system (CPCS) performs various protection logics against many transients and certain accidents. The CPCS is a real-time computer system calculating the departure from nucleate boiling ratio (DNBR), and local power density, and other protection logics. It takes process variables such as neutron flux, hot-leg temperature, cold-leg temperature, control element assembly positions, and reactor coolant pump shaft speed. Since the CPCS protection logics are quite complex, it is difficult for an operator to tell immediately which parameter is the major cause of the reactor trip. Thus, whenever the reactor trip signal is generated, the process input variables and calculated results, including selected intermediate variables, are frozen in the specified computer memory for later analysis. These frozen variables are called the trip buffer. Analysis of the trip buffer requires an expert in the CPCS and related documents containing algorithms and a data base for algorithms. The Trip Buffer Analysis Program (TBAP) is an expert system that pinpoints the causes of the CPCS initiated reactor trip, thus relieving the operator from the burden of analyzing the trip buffer

  10. How combined trip purposes are associated with transport choice for short distance trips. Results from a cross-sectional study in the Netherlands.

    Directory of Open Access Journals (Sweden)

    Eline Scheepers

    Full Text Available One way to increase physical activity is to stimulate a shift from car use to walking or cycling. In single-purpose trips, purpose was found to be an important predictor of transport choice. However, as far as known, no studies have been conducted to see how trips with combined purposes affect this decision. This study was designed to provide insight into associations between combined purposes and transport choice.An online questionnaire (N = 3,663 was used to collect data concerning transport choice for four primary purposes: shopping, going to public natural spaces, sports, and commuting. Per combination of primary trip purpose and transport choice, participants were asked to give examples of secondary purposes that they combine with the primary purpose. Logistic regression analyses were used to model the odds of both cycling and walking versus car use.Primary trip purposes combined with commuting, shopping, visiting private contacts or medical care were more likely to be made by car than by cycling or walking. Combinations with visiting catering facilities, trips to social infrastructure facilities, recreational outings, trips to facilities for the provision of daily requirements or private contacts during the trip were more likely to be made by walking and/or cycling than by car.Combined trip purposes were found to be associated with transport choice. When stimulating active transport focus should be on the combined-trip purposes which were more likely to be made by car, namely trips combined with commuting, other shopping, visiting private contacts or medical care.

  11. Using GIS for planning field trips: In-situ assessment of Geopoints for field trips with mobile devices

    Science.gov (United States)

    Böhm, Sarah; Kisser, Thomas; Ditter, Raimund

    2016-04-01

    Up to now no application is existing for collecting data via mobile devices using a geographical information system referring to the evaluation of Geopoints. Classified in different geographical topics a Geopark can be rated for suitability of Geopoints for field trips. The systematically acquisition of the suitability of Geopoints is necessary, especially when doing field trips with lower grade students who see a physical-geographic phenomenon for the first time. For this reason, the development of such an application is an invention for easy handling evaluations of Geopoints on the basis of commonly valid criteria like esthetic attraction, interestingness, and pithiness (Streifinger 2010). Collecting data provides the opportunity of receiving information of particularly suitable Geopoints out of the sight from students, tourists and others. One solution for collecting data in a simple and intuitive form is Survey123 for ArcGIS (http://survey123.esri.com/#/). You can create surveys using an ArcGIS Online organizational account and download your own survey or surveys "that may have been shared with you" (https://itunes.apple.com/us/app/survey-123-for-arcgis/id993015031?mt=8) on your mobile device. "Once a form is downloaded, you will be able to start collecting data."(https://itunes.apple.com/us/app/survey-123-for-arcgis/id993015031?mt=8) Free of cost and use while disconnected the application can easily be used via mobile device on field trips. On a 3-day field trip which is held three times per year in the Geopark Bergstraße-Odenwald Survey123 is being used to evaluate the suitability of different Geopoints for different topics (geology, soils, vegetation, climate). With every field trip about 25 students take part in the survey and evaluate each Geopoint at the route. So, over the time, the docents know exactly which Geopoints suites perfect for teaching geology for example, and why it suites that good. The field trip is organized in an innovative way. Before

  12. Potential conflict between TRIPS and GATT concerning parallel importation of drugs and possible solution to prevent undesirable market segmentation.

    Science.gov (United States)

    Lo, Chang-Fa

    2011-01-01

    From international perspective, parallel importation, especially with respect to drugs, has to do with the exhaustion principle in Article 6 of the TRIPS Agreement and the general exception in Article XX of the GATT 1994. Issues concerning the TRIPS Agreement have been constant topics of discussion. However, parallel importation in relation to the general rules of the GATT 1994 as well as to its exceptions provided in Article XX was not seriously discussed. In the view of the paper, there is a conflict between the provisions in these two agreements. The paper explains such conflict and tries to propose a method of interpretation to resolve the conflict between GATT Article XX and TRIPS Article 6 concerning parallel importation for the purpose of reducing the possible undesirable market segmentation in pharmaceutical sector. The method suggested in the paper is a proper application of good faith principle in the Vienna Convention to interpret GATT Article XX, so that there could be some flexibility for those prohibitions of parallel importation which have positive effect on international trade.

  13. 28 CFR 570.45 - Violation of escorted trip.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Violation of escorted trip. 570.45 Section 570.45 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE COMMUNITY PROGRAMS AND RELEASE COMMUNITY PROGRAMS Escorted Trips § 570.45 Violation of escorted trip. (a) Staff shall process as...

  14. SOCIO-ECONOMIC STUDY OF SUPLIT STONE BREAKER WOMEN IN SUPPORTING FAMILY LIFE: A CASE STUDY OF INFORMAL SECTOR STONE BREAKER WORKER IN THE NORTH MORAMO, INDONESIA

    Directory of Open Access Journals (Sweden)

    Kambolong M.

    2017-10-01

    Full Text Available A socio-economic study of Suplit Stone breaker women In Supporting Family life is a study of the Informal Sector Workers carried out in the form of a survey. This study aims to assess the socio-economic level of the workers, educational level, results achieved, income levels, health effects, and household's social condition. This research will specifically study and analyze income received, identify and examine the issues that arise in performing stone breaker as an occupation: deficiencies, expectations, and negative impacts. Ten urban villages/villages in Moramo North District was taken as research population. Area samples taken were five (5 urban/rural where workers are concentrated in Lalowaru Village, Puasana Village, Mata Mawatu Village, Sanggula Village, and Lamokula Village. Samples community were 5 percent of all household. Therefore total samples taken were 93 people scattered in villages. Research informants are Head of North Morano district, Stone Processing owner, and stone carrier driver. Data collection was conducted by observation, interview using a list of questions, as well as documentation of objective conditions. Data were analyzed using descriptive analysis techniques, which describe the objective conditions of the field in accordance with the purpose of research. Research result shows workers are housewives who help their husbands and families to supplement the household income to support family life. In general, socio-economic conditions of women suplit stone breaker is relatively low, their education level is generally elementary or none. The results achieved are still limited by an average of IDR 30,000, per day/worker is calculated based on the total stone yield. These women perform their work using simple tools such as hammer and gloves. The negative impact on eye health and breathing difficulty caused by inhaling stone dust every day. The problems faced by the workers is the lack of working capital to be trying to own

  15. Observing Trip Chain Characteristics of Round-Trip Carsharing Users in China: A Case Study Based on GPS Data in Hangzhou City

    Directory of Open Access Journals (Sweden)

    Ying Hui

    2017-06-01

    Full Text Available Carsharing as a means to provide individuals with access to automobiles to complete a personal trip has grown significantly in recent years in China. However, there are few case studies based on operational data to show the role carsharing systems play in citizens’ daily trips. In this study, vehicle GPS data of a round-trip carsharing system in Hangzhou, China was used to describe the trip chain characteristics of users. For clearer delineation of carshare usage, the car use time length of all observations chosen in the study was within 24 h or less. Through data preprocessing, a large pool (26,085 of valid behavior samples was obtained, and several trip chaining attributes were selected to describe the characteristics. The pool of observations was then classified into five clusters, with each cluster having significant differences in one or two trip chain characteristics. The cluster results reflected that different use patterns exist. By a comparative analysis with trip survey data in Hangzhou, differences in trip chain characteristics exist between carsharing and private cars, but in some cases, shared vehicles can be a substitute for private cars to satisfy motorized travel. The proposed method could facilitate companies in formulating a flexible pricing strategy and determining target customers. In addition, traffic administration agencies could have a deeper understanding of the position and function of various carsharing modes in an urban transportation system.

  16. Field Trip - Conservation of Carnivores in Namibia

    Science.gov (United States)

    Gibson, Amanda

    2017-04-01

    Field trips are a key component of our curriculum at ISWB. Classroom teaching is invaluable but field trips provide pupils with a tangible connection to pertinent issues of conservation. ISWB realises the importance of out of the classroom learning in field trips and to this end our students have an opportunity to partake in a number of 3-5 day field trips per academic year. In 2016, several Year 8, 9, 10, 11 and 12 students visited the AfriCat Foundation on Okonjima in central Namibia for 4 days to learn about the conservation of the predator population in Namibia. The trips were very successful and another trip this year to AfriCat North close to Etosha National Park, where the students will work closely with the local farming communities, is planned. AfriCat provides Environmental Education programmes for the youth of Namibia giving them a greater understanding of the importance of wildlife conservation. Their main objective is promoting predator and environmental awareness amongst the youth of Namibia. AfriCat Environmental Education Programme is based on 1997 UNESCO-UNEP Environmental Education objectives. "Attitudes: To raise concern about problems, values, personal responsibility and willingness to participate/act. In the end, we conserve only what we love. We will love only what we understand. We will understand only what we are taught."

  17. A study of plunging breaker mechanics by PIV measurements and a Navier-Stokes solver

    DEFF Research Database (Denmark)

    Emarat, Narumon; Forehand, David I. M.; Christensen, Erik Damgaard

    2000-01-01

    The mechanics of a surf-zone plunging breaker are studied from Particle Image Velocimetry (PIV) measurements and a numerical model based on the Navier-Stokes equations, using a Volume of Fluid (VOF) method. An additional numerical model using a Boundary-Integral Method (BIM) is also used in order...

  18. Evidence, explanations, and recommendations for teachers' field trip strategies

    Science.gov (United States)

    Rebar, Bryan

    Field trips are well recognized by researchers as an educational approach with the potential to complement and enhance classroom science teaching by exposing students to unique activities, resources, and content in informal settings. The following investigation addresses teachers' field trip practices in three related manuscripts: (1) A study examining the details of teachers' pedagogical strategies intended to facilitate connections between students' experiences and the school curricula while visiting an aquarium; (2) A study documenting and describing sources of knowledge that teachers draw from when leading field trips to an aquarium; (3) A position paper that reviews and summarizes research on effective pedagogical strategies for field trips. Together these three pieces address key questions regarding teachers' practices on field trips: (1) What strategies are teachers employing (and not employing) during self-guided field trips to facilitate learning tied to the class curriculum? (2) What sources of knowledge do teachers utilize when leading field trips? (3) How can teachers be better prepared to lead trips that promote learning? The Oregon Coast Aquarium served as the field trip site for teachers included in this study. The setting suited these questions because the aquarium serves tens of thousands of students on field trips each year but provides no targeted programming for these students as they explore the exhibits. In other words, the teachers who lead field trips assume much of the responsibility for facilitating students' experience. In order to describe and characterize teachers' strategies to link students' experiences to the curriculum, a number of teachers (26) were observed as they led their students' visit to the public spaces of the aquarium. Artifacts, such as worksheets, used during the visit were collected for analysis as well. Subsequently, all teachers were surveyed regarding their use of the field trip and their sources of knowledge for

  19. Tests of a vacuum breaker for the FTU commutation system

    International Nuclear Information System (INIS)

    Andreani, R.; Lovisetto, L.; Cornago, F.

    1984-01-01

    A two poles vacuum breaker, equipped with saturable inductances and capacitor banks to produce an artificial current zero, appears the most suitable solution to satisfy these requirements with high reliability of operation and limited maintenance. Two series of tests have been conducted to evaluate the performance and reliability of the system and in particular the erosion of the electrodes as a function of number of operations. The test results have been very satisfactory. At least 1000 full power pulses can be envisaged before replacing the vacuum bottles. (author)

  20. Elementary school children's science learning from school field trips

    Science.gov (United States)

    Glick, Marilyn Petty

    This research examines the impact of classroom anchoring activities on elementary school students' science learning from a school field trip. Although there is prior research demonstrating that students can learn science from school field trips, most of this research is descriptive in nature and does not examine the conditions that enhance or facilitate such learning. The current study draws upon research in psychology and education to create an intervention that is designed to enhance what students learn from school science field trips. The intervention comprises of a set of "anchoring" activities that include: (1) Orientation to context, (2) Discussion to activate prior knowledge and generate questions, (3) Use of field notebooks during the field trip to record observations and answer questions generated prior to field trip, (4) Post-visit discussion of what was learned. The effects of the intervention are examined by comparing two groups of students: an intervention group which receives anchoring classroom activities related to their field trip and an equivalent control group which visits the same field trip site for the same duration but does not receive any anchoring classroom activities. Learning of target concepts in both groups was compared using objective pre and posttests. Additionally, a subset of students in each group were interviewed to obtain more detailed descriptive data on what children learned through their field trip.

  1. Microstructure characterization of Friction Stir Spot Welded TRIP steel

    DEFF Research Database (Denmark)

    Lomholt, Trine Colding; Adachi, Yoshitaka; Peterson, Jeremy

    2012-01-01

    Transformation Induced Plasticity (TRIP) steels have not yet been successfully joined by any welding technique. It is desirable to search for a suitable welding technique that opens up for full usability of TRIP steels. In this study, the potential of joining TRIP steel with Friction Stir Spot...

  2. Austenite stability in TRIP steels studied by synchrotron radiation

    NARCIS (Netherlands)

    Blondé, R.

    2014-01-01

    TRIP steel is a material providing great mechanical properties. Such steels show a good balance between high-strength and ductility, not only as a result of the fine microstructure, but also because of the well-known TRIP effect. The Transformation Induced-Plasticity (TRIP) phenomenon is the

  3. Multi-Destination and Multi-Purpose Trip Effects in the Analysis of the Demand for Trips to a Remote Recreational Site

    Science.gov (United States)

    Martínez-Espiñeira, Roberto; Amoako-Tuffour, Joe

    2009-06-01

    One of the basic assumptions of the travel cost method for recreational demand analysis is that the travel cost is always incurred for a single purpose recreational trip. Several studies have skirted around the issue with simplifying assumptions and dropping observations considered as nonconventional holiday-makers or as nontraditional visitors from the sample. The effect of such simplifications on the benefit estimates remains conjectural. Given the remoteness of notable recreational parks, multi-destination or multi-purpose trips are not uncommon. This article examines the consequences of allocating travel costs to a recreational site when some trips were taken for purposes other than recreation and/or included visits to other recreational sites. Using a multi-purpose weighting approach on data from Gros Morne National Park, Canada, we conclude that a proper correction for multi-destination or multi-purpose trip is more of what is needed to avoid potential biases in the estimated effects of the price (travel-cost) variable and of the income variable in the trip generation equation.

  4. Sistem Proteksi Arus Bocor Menggunakan Earth Leakage Circuit Breaker Berbasis Arduino

    OpenAIRE

    Syukriyadin, Syukriyadin

    2016-01-01

    Touching a live part of electrical equipment either intentionally or unintentionally can cause an electric shock. The touch can occur directly or indirectly and results in the flow of electric current through the human body to the ground. This electric current is known as the leakage current and can have fatal effects on the human body such as burns, cramps, faint and death. This paper aims to design a prototype protection model of the earth leakage circuit breaker device based on Arduino (EL...

  5. A model for TRIP steel constitutive behaviour

    NARCIS (Netherlands)

    Perdahcioglu, Emin Semih; Geijselaers, Hubertus J.M.; Menari, G

    2011-01-01

    A constitutive model is developed for TRIP steel. This is a steel which contains three or four different phases in its microstructure. One of the phases in TRIP steels is metastable austenite (Retained Austenite) which transforms to martensite upon deformation. The accompanying transformation strain

  6. Transforming an Exposure trip to Botanical Expedition: Introducing Ecological Research thru Exposure Trip in an Eco-tourism Site

    Directory of Open Access Journals (Sweden)

    Bernardo C. Lunar

    2014-10-01

    Full Text Available – Fieldtrips can be considered as one of the three avenues through which science can be taught - through formal classroom teaching, practical work and field trips. An exposure trip at Bangkong Kahoy Valley Field Study Center was arranged for a class of BS Biology and BS Education students enrolled in Ecology Course. This approach purposefully transformed the usual exposure trip from being a casual site visit into a focused and productive learning experience. This transformation from exposure trip to a botanical expedition has exceeded the initial activity goals. Rather than a day off from learning, the time spent at the study center has been a meaningful opportunity to engage students in an active ecological research project while delivering valuable science content. Employing the descriptive survey design, the learning gains of the students were assessed and students were directed to do a guided reflection writing using the ORID Model of Focused Conversation. The learning gains and reflections of the students confirmed that students can collaboratively develop focused research questions, make meaning from a variety of sources, carry out a vegetation analysis and conduct surveys on socio-economic status, plant resource utilization and ecotourism assessment of the host community. As students prepared for their trip and synthesized their learning afterward, they were able to come up with very impressive and scientifically sound research outputs.

  7. Ballplayer or barrier breaker? Branding through the seven statues of Jackie Robinson

    OpenAIRE

    Stride, C.; Thomas, F.; Smith, M.M.

    2014-01-01

    Jackie Robinson is the baseball player most frequently depicted by a public statue within the USA, a ubiquity explained by his unique position as barrier breaker of the Major League colour bar. Utilising a detailed inspection of statue designs, locations and inscriptions, and comparisons with wider baseball statuary, Robinson's monuments reveal a distinctive set of cultural projections. These are commemorations distinguished by their age, location away from MLB ballparks, lack of action poses...

  8. Trip electrical circuit of the gyrotion

    International Nuclear Information System (INIS)

    Rossi, J.O.

    1987-09-01

    The electron cyclotron resonance heating system of INPE/LAP is shown and the trip electrical circuit of the gyrotron is described, together with its fundamental aspects. The trip electrical circuit consists basically of a series regulator circuit which regulates the output voltage level and controls the pulse width time. Besides that, a protection circuit for both tubes, regulator and gyrotron, against faults in the system. (author) [pt

  9. Complementary, substitution, and independence among tourist trips

    NARCIS (Netherlands)

    Middelkoop, van M.; Borgers, A.W.J.; Timmermans, H.J.P.

    1999-01-01

    The relationship between day trips, short breaks (2-4 days), and holidays (5+ days) has never been examined at the level of the individual consumer because surveys on day and overnight trips are typically conducted independently. In this article, both the stated and the inferred relationship between

  10. Single Point Vulnerability Analysis of Automatic Seismic Trip System

    International Nuclear Information System (INIS)

    Oh, Seo Bin; Chung, Soon Il; Lee, Yong Suk; Choi, Byung Pil

    2016-01-01

    Single Point Vulnerability (SPV) analysis is a process used to identify individual equipment whose failure alone will result in a reactor trip, turbine generator failure, or power reduction of more than 50%. Automatic Seismic Trip System (ASTS) is a newly installed system to ensure the safety of plant when earthquake occurs. Since this system directly shuts down the reactor, the failure or malfunction of its system component can cause a reactor trip more frequently than other systems. Therefore, an SPV analysis of ASTS is necessary to maintain its essential performance. To analyze SPV for ASTS, failure mode and effect analysis (FMEA) and fault tree analysis (FTA) was performed. In this study, FMEA and FTA methods were performed to select SPV equipment of ASTS. D/O, D/I, A/I card, seismic sensor, and trip relay had an effect on the reactor trip but their single failure will not cause reactor trip. In conclusion, ASTS is excluded as SPV. These results can be utilized as the basis data for ways to enhance facility reliability such as design modification and improvement of preventive maintenance procedure

  11. Single Point Vulnerability Analysis of Automatic Seismic Trip System

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Seo Bin; Chung, Soon Il; Lee, Yong Suk [FNC Technology Co., Yongin (Korea, Republic of); Choi, Byung Pil [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    Single Point Vulnerability (SPV) analysis is a process used to identify individual equipment whose failure alone will result in a reactor trip, turbine generator failure, or power reduction of more than 50%. Automatic Seismic Trip System (ASTS) is a newly installed system to ensure the safety of plant when earthquake occurs. Since this system directly shuts down the reactor, the failure or malfunction of its system component can cause a reactor trip more frequently than other systems. Therefore, an SPV analysis of ASTS is necessary to maintain its essential performance. To analyze SPV for ASTS, failure mode and effect analysis (FMEA) and fault tree analysis (FTA) was performed. In this study, FMEA and FTA methods were performed to select SPV equipment of ASTS. D/O, D/I, A/I card, seismic sensor, and trip relay had an effect on the reactor trip but their single failure will not cause reactor trip. In conclusion, ASTS is excluded as SPV. These results can be utilized as the basis data for ways to enhance facility reliability such as design modification and improvement of preventive maintenance procedure.

  12. Transient studies in large offshore wind farms, taking into account network/circuit breaker interaction

    DEFF Research Database (Denmark)

    Glasdam, Jacob Bærholm; Bak, Claus Leth; Hjerrild, Jesper

    2011-01-01

    to ensure reliable switching operations. Transient measurement results in an OWF are compared with simulation results in PSCAD EMTDC and DigSILENT Power Factory, where a user-defined model of the vacuum circuit breaker (VCB) is included, capable of simulating multiple prestrikes during the closing operation...... the simulation results, whereas little improvement is found in DigSILENT....

  13. Propagation of the trip behavior in the VENUS vertex chamber

    International Nuclear Information System (INIS)

    Ohama, Taro; Yamada, Yoshikazu.

    1995-03-01

    The high voltage system of the VENUS vertex chamber occasionally trips by a discharge somewhere among cathode electrodes during data taking. This trip behavior induces often additional trips at other electrodes such as the skin and the grid electrodes in the vertex chamber. This propagation mechanism of trips is so complicated in this system related with multi-electrodes. Although the vertex chamber is already installed inside the VENUS detector and consequently the discharge is not able to observe directly, a trial to estimate the propagation has been done using only the information which appears around the trip circuits and the power supply of the vertex chamber. (author)

  14. Language Travel or Language Tourism: Have Educational Trips Changed So Much?

    Science.gov (United States)

    Laborda, Jesus Garcia

    2007-01-01

    This article points out the changes in organization, students and language learning that language trips, as contrasted with educational trips (of which language trips are a subgroup) have gone through in the last years. The article emphasizes the need to differentiate between language trips and language tourism based on issues of additional…

  15. Double system wave energy converter for the breaker zone

    International Nuclear Information System (INIS)

    Malavasi, Stefano; Negri; Marco

    2015-01-01

    In this paper a particular type of wave energy converter, namely EDS (Energy Double System) is presented. It is a two-body point absorber composed by a heaving float and a surging paddle, mounted on the same structure and aligned along the wave propagation direction. The system is designed for working in the breaker zone, where waves close to breaking can generate a considerable surging force on the paddle. A scale EDS model has been built and tested in the wave flume of the Hydraulics Laboratory of the 'Politecnico' of Milan. The power absorbed by the system, varying its configuration, position and wave, has been measured, and interesting efficiencies have been found.

  16. A Trip to the Zoo: Children's Words and Photographs.

    Science.gov (United States)

    DeMarie, Darlene

    Field trips are a regular part of many programs for young children. Field trips can serve a variety of purposes, such as exposing children to new things or helping children to see familiar things in new ways. The purpose of this study was to learn the meaning children gave to a field trip. Cameras were made available to each of the children in a…

  17. Flow in Rotating Serpentine Coolant Passages With Skewed Trip Strips

    Science.gov (United States)

    Tse, David G.N.; Steuber, Gary

    1996-01-01

    Laser velocimetry was utilized to map the velocity field in serpentine turbine blade cooling passages with skewed trip strips. The measurements were obtained at Reynolds and Rotation numbers of 25,000 and 0.24 to assess the influence of trips, passage curvature and Coriolis force on the flow field. The interaction of the secondary flows induced by skewed trips with the passage rotation produces a swirling vortex and a corner recirculation zone. With trips skewed at +45 deg, the secondary flows remain unaltered as the cross-flow proceeds from the passage to the turn. However, the flow characteristics at these locations differ when trips are skewed at -45 deg. Changes in the flow structure are expected to augment heat transfer, in agreement with the heat transfer measurements of Johnson, et al. The present results show that trips are skewed at -45 deg in the outward flow passage and trips are skewed at +45 deg in the inward flow passage maximize heat transfer. Details of the present measurements were related to the heat transfer measurements of Johnson, et al. to relate fluid flow and heat transfer measurements.

  18. Formation and development of a breaker bar under regular waves. Part 2: Sediment transport and morphology

    DEFF Research Database (Denmark)

    Jacobsen, Niels Gjøl; Fredsøe, Jørgen

    2014-01-01

    In Part 2 of this work, the hydrodynamic model described in Part 1 is applied for the simulation of sediment transport and the associated morphological development of breaker bars. The sediment description is split into bed load and suspended load, and like the hydrodynamics the sediment transport...

  19. Analysis of Peach Bottom turbine trip tests

    International Nuclear Information System (INIS)

    Cheng, H.S.; Lu, M.S.; Hsu, C.J.; Shier, W.G.; Diamond, D.J.; Levine, M.M.; Odar, F.

    1979-01-01

    Current interest in the analysis of turbine trip transients has been generated by the recent tests performed at the Peach Bottom (Unit 2) reactor. Three tests, simulating turbine trip transients, were performed at different initial power and coolant flow conditions. The data from these tests provide considerable information to aid qualification of computer codes that are currently used in BWR design analysis. The results are presented of an analysis of a turbine trip transient using the RELAP-3B and the BNL-TWIGL computer codes. Specific results are provided comparing the calculated reactor power and system pressures with the test data. Excellent agreement for all three test transients is evident from the comparisons

  20. Adaptive protection algorithm and system

    Science.gov (United States)

    Hedrick, Paul [Pittsburgh, PA; Toms, Helen L [Irwin, PA; Miller, Roger M [Mars, PA

    2009-04-28

    An adaptive protection algorithm and system for protecting electrical distribution systems traces the flow of power through a distribution system, assigns a value (or rank) to each circuit breaker in the system and then determines the appropriate trip set points based on the assigned rank.

  1. Actual and Virtual Reality: Making the Most of Field Trips.

    Science.gov (United States)

    Bellan, Jennifer Marie; Scheurman, Geoffrey

    1998-01-01

    Argues that a virtual field trip can complement and enhance a real one. Discusses the benefits and pitfalls of both types of field trips. Outlines a series of student and teacher activities combining an actual field trip and a virtual one to Fort Snelling in St. Paul, Minnesota. (MJP)

  2. Vanpool trip planning based on evolutionary multiple objective optimization

    Science.gov (United States)

    Zhao, Ming; Yang, Disheng; Feng, Shibing; Liu, Hengchang

    2017-08-01

    Carpool and vanpool draw a lot of researchers’ attention, which is the emphasis of this paper. A concrete vanpool operation definition is given, based on the given definition, this paper tackles vanpool operation optimization using user experience decline index(UEDI). This paper is focused on making each user having identical UEDI and the system having minimum sum of all users’ UEDI. Three contributions are made, the first contribution is a vanpool operation scheme diagram, each component of the scheme is explained in detail. The second contribution is getting all customer’s UEDI as a set, standard deviation and sum of all users’ UEDI set are used as objectives in multiple objective optimization to decide trip start address, trip start time and trip destination address. The third contribution is a trip planning algorithm, which tries to minimize the sum of all users’ UEDI. Geographical distribution of the charging stations and utilization rate of the charging stations are considered in the trip planning process.

  3. HOW DO YOUNG PEOPLE SELECT INFORMATION TO PLAN A TRIP

    Directory of Open Access Journals (Sweden)

    Oana ŢUGULEA

    2013-12-01

    Full Text Available The purpose of the research is to reveal the young tourists preferences in the process of planning a trip. Sources of information used, the utility of Internet/travel agencies in planning travel trip activities, preferred means of transportation and types of accommodation are investigated. As research methods, there used both qualitative and quantitative methods: focus group and survey. Internet is more used by young tourists in planning trips than travel agencies are. Internet is considered more useful in the documentation stage and when buying airline tickets. Young tourists are more influenced by friends when planning a trip. Young tourists prefer cars and planes as means of transportation for a trip and hotels and guesthouses as accommodation when traveling.

  4. Hybrid intelligent monironing systems for thermal power plant trips

    Science.gov (United States)

    Barsoum, Nader; Ismail, Firas Basim

    2012-11-01

    Steam boiler is one of the main equipment in thermal power plants. If the steam boiler trips it may lead to entire shutdown of the plant, which is economically burdensome. Early boiler trips monitoring is crucial to maintain normal and safe operational conditions. In the present work two artificial intelligent monitoring systems specialized in boiler trips have been proposed and coded within the MATLAB environment. The training and validation of the two systems has been performed using real operational data captured from the plant control system of selected power plant. An integrated plant data preparation framework for seven boiler trips with related operational variables has been proposed for IMSs data analysis. The first IMS represents the use of pure Artificial Neural Network system for boiler trip detection. All seven boiler trips under consideration have been detected by IMSs before or at the same time of the plant control system. The second IMS represents the use of Genetic Algorithms and Artificial Neural Networks as a hybrid intelligent system. A slightly lower root mean square error was observed in the second system which reveals that the hybrid intelligent system performed better than the pure neural network system. Also, the optimal selection of the most influencing variables performed successfully by the hybrid intelligent system.

  5. Transient Studies in Large Offshore Wind Farms, Tak-ing Into Account Network/Circuit Breaker Interaction

    DEFF Research Database (Denmark)

    Glasdam, Jakob; Bak, Claus Leth; Hjerrild, Jesper

    2011-01-01

    to ensure reliable switching operations. Transient measurement results in an OWF are compared with simulation results in PSCAD EMTDC and DigSILENT Power Factory, where a user-defined model of the vacuum circuit breaker (VCB) is included, capable of simulating multiple prestrikes during the closing operation...... the simulation results, whereas little improvement is found in DigSILENT....

  6. Questionnaire-based person trip visualization and its integration to quantitative measurements in Myanmar

    Science.gov (United States)

    Kimijiama, S.; Nagai, M.

    2016-06-01

    With telecommunication development in Myanmar, person trip survey is supposed to shift from conversational questionnaire to GPS survey. Integration of both historical questionnaire data to GPS survey and visualizing them are very important to evaluate chronological trip changes with socio-economic and environmental events. The objectives of this paper are to: (a) visualize questionnaire-based person trip data, (b) compare the errors between questionnaire and GPS data sets with respect to sex and age and (c) assess the trip behaviour in time-series. Totally, 345 individual respondents were selected through random stratification to assess person trip using a questionnaire and GPS survey for each. Conversion of trip information such as a destination from the questionnaires was conducted by using GIS. The results show that errors between the two data sets in the number of trips, total trip distance and total trip duration are 25.5%, 33.2% and 37.2%, respectively. The smaller errors are found among working-age females mainly employed with the project-related activities generated by foreign investment. The trip distant was yearly increased. The study concluded that visualization of questionnaire-based person trip data and integrating them to current quantitative measurements are very useful to explore historical trip changes and understand impacts from socio-economic events.

  7. The Role of Infragravity Waves in Near-Bed Cross-Shore Sediment Flux in the Breaker Zone

    Directory of Open Access Journals (Sweden)

    Samantha Kularatne

    2014-08-01

    Full Text Available Results from a series of field experiments, conducted to investigate the influence of infragravity waves (from wave groups, ripple type and location relative to the breaker line on cross-shore suspended sediment flux close to the sea bed in nearshore environments, are presented. The field data were collected from Cable Beach (Broome and Mullaloo Beach in Western Australia and Chilaw in Sri Lanka. These beaches experience different incident wave, tidal and morphological conditions, with Cable Beach having a 10-m spring tidal range, whilst the other two beaches have tidal ranges <1.0 m. Measurements included simultaneous records of surface elevation, two-dimensional horizontal current velocities and suspended sediment concentrations, together with half-hourly observations of the seabed topography. Although most of the data sets were obtained just outside of the surf zone, a few results from inside of the surf zone were also included. A significant correlation between wave groups and suspended sediment concentration was found at all of the measurement sites, either with or without bed ripples. The direction and magnitude of cross-shore suspended sediment flux varied with location with respect to the breaker line; however, other parameters, such as bed ripples and velocity skewness, could have influenced this result. In Broome, where the measurement location with respect to the breaker line varied with the tidal cycle, the cross-shore sediment flux due to swell waves was shoreward inside and just outside of the surf zone and seaward farther offshore of the breaker line. Further, sediment flux due to swell waves was onshore when the seabed was flat and offshore over post-vortex ripples. Sediment flux due to swell waves was onshore when the normalised velocity skewness towards the shore was high (positive; the flux was offshore when the skewness was lower, but positive, suggesting the influence of other parameters, such as ripples and grain size. The

  8. Echoes from the Field: An Ethnographic Investigation of Outdoor Science Field Trips

    Science.gov (United States)

    Boxerman, Jonathan Zvi

    As popular as field trips are, one might think they have been well-studied. Nonetheless, field trips have not been heavily studied, and little research has mapped what actually transpires during field trips. Accordingly, to address this research gap, I asked two related research questions. The first question is a descriptive one: What happens on field trips? The second question is explanatory: What field trip events are memorable and why? I employed design research and ethnographic methodologies to study learning in naturally occurring contexts. I collaborated with middle-school science teachers to design and implement more than a dozen field trips. The field trips were nested in particular biology and earth sciences focal units. Students were tasked with making scientific observations in the field and then analyzing this data during classroom activities. Audio and video recording devices captured what happened during the field trips, classroom activities and discussions, and the interviews. I conducted comparative microanalysis of videotaped interactions. I observed dozens of events during the field trips that reverberated across time and place. I characterize the features of these events and the objects that drew interest. Then, I trace the residue across contexts. This study suggests that field trips could be more than one-off experiences and have the potential to be resources to seed and enrich learning and to augment interest in the practice of science.

  9. TRIPS, the Doha declaration and paragraph 6 decision: what are the remaining steps for protecting access to medicines?

    Directory of Open Access Journals (Sweden)

    Lee Kelley

    2007-05-01

    Full Text Available Abstract Background The World Trade Organisation's Declaration on the TRIPS Agreement and Public Health (known as the Doha Declaration of 2001, and subsequent Decision on the Interpretation of Paragraph 6 reached in 2003, affirmed the flexibilities available under the Agreement on Trade Related Property Rights (TRIPS to member states seeking to protect public health. Despite these important clarifications, the actual implementation of these measures to improve access to medicines remains uncertain. There are also concerns that so-called TRIPS-plus measures within many regional and bilateral trade agreements are further undermining the capacity of the poor to access affordable medicines. Methods The paper reviews policy debates among governments, nongovernmental organisations and international organisations from 1995, and notably since 2003, surrounding access to medicines and trade agreements. The provisions for protecting public health provided by the Doha Declaration and Paragraph 6 Decision are reviewed in terms of challenges for implementation, along with measures to protect intellectual property rights (IPRs under selected regional and bilateral trade agreements. Results While provisions, in principle, were affirmed for member states under the TRIPS agreement to protect public health, numerous challenges remain. Implementation of the flexibilities has been hindered by lack of capacity in many LMICs. More intransigent have been stark inequalities in power and influence among trading nations, leaving LMICs vulnerable to pressures to permit the globalization of IPRs in order to protect broader trade and economic interests. Such inequalities are apparent in proposals or adopted TRIPS-plus measures which re-establish the primacy of trade over public health goals. Conclusion Despite being hailed as a "watershed in international trade", the Doha Declaration and Paragraph 6 decision have not resolved the problem of access to affordable medicines

  10. Accommodation of the spinal cat to a tripping perturbation

    Directory of Open Access Journals (Sweden)

    Hui eZhong

    2012-05-01

    Full Text Available Adult cats with a complete spinal cord transection at T12-T13 can relearn over a period of days-to-weeks how to generate full weight-bearing stepping on a treadmill or standing ability if trained specifically for that task. In the present study, we assessed short-term (msec-min adaptations by repetitively imposing a mechanical perturbation on the hindlimb of chronic spinal cats by placing a rod in the path of the leg during the swing phase to trigger a tripping response. The kinematics and EMG were recorded during control (10 steps, trip (1 to 60 steps with various patterns and then release (without any tripping stimulus, 10 to 20 steps sequences. Our data show that the activation patterns and kinematics of the hindlimb in the step cycle immediately following the initial trip (mechanosensory stimulation of the dorsal surface of the paw was modified in a way that increased the probability of avoiding the obstacle in the subsequent step. This indicates that the spinal sensorimotor circuitry reprogrammed the trajectory of the swing following a perturbation prior to the initiation of the swing phase of the subsequent step, in effect attempting to avoid the re-occurrence of the perturbation. The average height of the release steps was elevated compared to control regardless of the pattern and the length of the trip sequences. In addition, the average impact force on the tripping rod tended to be lower with repeated exposure to the tripping stimulus. EMG recordings suggest that the semitendinosus, a primary knee flexor, was a major contributor to the adaptive tripping response. These results demonstrate that the lumbosacral locomotor circuitry can modulate the activation patterns of the hindlimb motor pools within the time frame of single step in a manner that tends to minimize repeated perturbations. Furthermore, these adaptations remained evident for a number of steps after removal of the mechanosensory stimulation.

  11. El aprendizaje bajo incertidumbre aplicado al mantenimiento de interruptores de potencia; Machine learning applied to the maintenance in high voltage breaker

    Directory of Open Access Journals (Sweden)

    Israel Gondres Torné

    2014-06-01

    Full Text Available La gestión del mantenimiento en las subestaciones eléctricas, así como en los interruptores de potencia ha evolucionado en el transcurso de los años de acuerdo a los equipos de medición de parámetros eléctricos y a las filosofías de mantenimiento mundial. El presente trabajo trata dichos avances desde una visión diferente, se utiliza la inteligencia artificial, específicamente el aprendizaje bajo incertidumbre para la toma de decisiones en la planificación del mantenimiento a los interruptores de potencia de una subestación. Se determina el índice de deterioro, los coeficientes de importancia del deterioro de cada tipo y del elemento del interruptor con la ayuda de los expertos. Posteriormente se obtienen los índices de membresías con los procesos correspondientes para la fusificación y defusificación; finalmente se realiza la evaluación de las reglas y defusificación para el tiempo de mantenimiento, implementando dicho método en diferentes interruptores de potencia. The maintenance management in electrical substations over the years has evolved according to the measurement equipment and the electrical parameters of global maintenance philosophies, and in particular the high voltage breakers have not been left behind. This paper is such advances from a different vision, artificial intelligence, specifically machine learning for decision-making in planning maintenance high voltage breaker sused in a substation. It determines the rate of deterioration, the coefficients of importance of each type of the deterioration and the high voltage breaker element with the help of experts. Subsequently are obtained the membership rates with the corresponding processes for fuzzification and defuzzification; finally the rule evaluation and defuzzification for the time maintenance is performed, the method is appliance in different high voltage breakers.

  12. Diagnosis technique for the detection of mechanical faults in power breakers; Tecnica de diagnostico para la deteccion de fallas mecanicas en interruptores de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Linan, Roberto; Perez, Marciano; Estrada, J. Manuel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    This article reports a non-invasive diagnosis technique for the detection of mechanical faults in power breakers, supporting it with the recording and analysis of vibration signals of the equipment under test. Also, an assessment of four breakers using this technique is presented. [Espanol] En el presente articulo se reporta una tecnica de diagnostico no invasiva para detectar fallas mecanicas en interruptores de potencia, apoyandose en el registro y analisis de senales de vibracion del equipo bajo prueba. Asimismo, se presenta la evaluacion de cuatro interruptores usando esta tecnica.

  13. Diagnosis technique for the detection of mechanical faults in power breakers; Tecnica de diagnostico para la deteccion de fallas mecanicas en interruptores de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Linan, Roberto; Perez, Marciano; Estrada, J Manuel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    This article reports a non-invasive diagnosis technique for the detection of mechanical faults in power breakers, supporting it with the recording and analysis of vibration signals of the equipment under test. Also, an assessment of four breakers using this technique is presented. [Espanol] En el presente articulo se reporta una tecnica de diagnostico no invasiva para detectar fallas mecanicas en interruptores de potencia, apoyandose en el registro y analisis de senales de vibracion del equipo bajo prueba. Asimismo, se presenta la evaluacion de cuatro interruptores usando esta tecnica.

  14. MCMII and the TriP chip

    Energy Technology Data Exchange (ETDEWEB)

    Juan Estrada et al.

    2003-12-19

    We describe the development of the electronics that will be used to read out the Fiber Tracker and Preshower detectors in Run IIb. This electronics is needed for operation at 132ns bunch crossing, and may provide a measurement of the z coordinate of the Fiber Tracker hits when operating at 396ns bunch crossing. Specifically, we describe the design and preliminary tests of the Trip chip, MCM IIa, MCM IIb and MCM IIc. This document also serves as a user manual for the Trip chip and the MCM.

  15. Power ion beam production in a magnetic-insulated diode placed in a circuit with an inductive storage with a plasmoerosion circuit breaker

    International Nuclear Information System (INIS)

    Anan'in, P.S.; Karpov, V.B.; Krasik, Ya.E.; Paul', E.A.

    1991-01-01

    Consideration is given to results of experimental studies of modes of operation of plasma current breaker and magnetic insulated diode, placed parallel in a circuit with inductive storage and microsecond generator, as well as parameters of high-power ion beam, generated in gas-filled diode. Magnetic field of mirror configuration, which enabled to locate the gas-filled diode dose to breaking region was used for decrease of electrodynamic plasma transfer. It is shown that time delay (of the order of ten and more) of power maximum in gas-filled diode with respect to power maximum in plasma breaker is observed when using passive plasma source on anode

  16. Transient Recovery Voltages at the Main 132kV Line Bay GIS Circuit Breaker in a Windfarm

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Okholm, J.; Holbøll, Joachim

    2011-01-01

    This paper presents the results of investigations of the Transient Recovery Voltage (TRV) across the terminals of the main 132kV Line Bay GIS circuit breaker (GIS CB) for Walney 2, second phase of the Walney Offshore Wind Farm. Several simulations were performed where the influence of different...

  17. The moderating role of shopping trip type in store satisfaction formation

    NARCIS (Netherlands)

    Hunneman, Auke; Verhoef, Pieter; Sloot, Laurentius

    Consumers may weigh store attributes differently depending on the type of shopping trip. For example, fill-in shoppers likely value convenience, due to the ad-hoc nature and urgency of such trips. However, no study has yet explored the effects of shopping trip types on satisfaction formation. This

  18. SAME-DAY TRIPS: A CHANCE OF URBAN DESTINATION DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Dario Simicevic

    2011-12-01

    Full Text Available The global economic crisis, the decline of standard and climatic factors influence the allocation of tourism trends at the global level. Certain types of tourist movements start up and develop; they have been present, but not sufficiently studied by authors. They also include a short trip or visit to a particular destination. Considering their characteristics, they do not require a lot of money and they make an increasingly important segment of the tourism market. Therefore, the importance of same-day trips should not be neglected on today's tourism market. Although in practice this part of the tourist offers and demand has not often been attached enough importance, same day trip can achieve a very significant inflow of funds and encourage the development of many potential tourist destinations. For all the reasons mentioned above, and because of its importance, the organization of same day-trips should be the fundamental basis and essential focus for tourism development. Taking into consideration that inbound tourist agencies show special interest for same-day trips, we have tried to give a starting point for further research in this part of the tourism market.

  19. Installation of a second trip system

    International Nuclear Information System (INIS)

    Bessada, E.

    1997-01-01

    Since its first criticality in 1957, the NRU reactor has been operating safely and efficiently supporting the CANDU reactor's research and development programs and producing radioisotopes for medical use. To ensure that the reactor continues to operate safely and effectively, Atomic Energy of Canada Limited (AECL) commissioned a team in 1989 to conduct a systematic review and assessment of the reactor condition. The outcome of the study indicated that the overall condition of the reactor is good and that it is being operated safely. The study also produced recommendations as to where safety can be improved. These recommendations are the basis of the upgrade program currently being implemented in the reactor. The Second Trip System (STS) is part of the upgrade program. It is a stand alone seismically qualified trip system that operates independently from the existing first trip system (FST) to shutdown the reactor. This paper discusses the design, installation and the inactive commissioning of the system, and the process used to ensure that the system can be retrofitted to the reactor without affecting its safety or its operational requirements. (author)

  20. Managing the effect of TRIPS on availability of priority vaccines.

    Science.gov (United States)

    Milstien, Julie; Kaddar, Miloud

    2006-05-01

    The stated purpose of intellectual property protection is to stimulate innovation. The Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) requires all Members of the World Trade Organization (WTO) to enact national laws conferring minimum standards of intellectual property protection by certain deadlines. Critics of the Agreement fear that such action is inconsistent with ensuring access to medicines in the developing world. A WHO convened meeting on intellectual property rights and vaccines in developing countries, on which this paper is based, found no evidence that TRIPS has stimulated innovation in developing market vaccine development (where markets are weak) or that protection of intellectual property rights has had a negative effect on access to vaccines. However, access to future vaccines in the developing world could be threatened by compliance with TRIPS. The management of such threats requires adherence of all countries to the Doha Declaration on TRIPS, and the protections guaranteed by the Agreement itself, vigilance on TRIPS-plus elements of free trade agreements, developing frameworks for licensing and technology transfer, and promoting innovative vaccine development in developing countries. The role of international organizations in defining best practices, dissemination of information, and monitoring TRIPS impact will be crucial to ensuring optimal access to priority new vaccines for the developing world.

  1. Unveiling E-Bike Potential for Commuting Trips from GPS Traces

    Directory of Open Access Journals (Sweden)

    Angel J. Lopez

    2017-06-01

    Full Text Available Common goals of sustainable mobility approaches are to reduce the need for travel, to facilitate modal shifts, to decrease trip distances and to improve energy efficiency in the transportation systems. Among these issues, modal shift plays an important role for the adoption of vehicles with fewer or zero emissions. Nowadays, the electric bike (e-bike is becoming a valid alternative to cars in urban areas. However, to promote modal shift, a better understanding of the mobility behaviour of e-bike users is required. In this paper, we investigate the mobility habits of e-bikers using GPS data collected in Belgium from 2014 to 2015. By analysing more than 10,000 trips, we provide insights about e-bike trip features such as: distance, duration and speed. In addition, we offer a deep look into which routes are preferred by bike owners in terms of their physical characteristics and how weather influences e-bike usage. Results show that trips with higher travel distances are performed during working days and are correlated with higher average speeds. Usage patterns extracted from our data set also indicate that e-bikes are preferred for commuting (home-work and business (work related trips rather than for recreational trips.

  2. Some notes on the big trip

    International Nuclear Information System (INIS)

    Gonzalez-Diaz, Pedro F.

    2006-01-01

    The big trip is a cosmological process thought to occur in the future by which the entire universe would be engulfed inside a gigantic wormhole and might travel through it along space and time. In this Letter we discuss different arguments that have been raised against the viability of that process, reaching the conclusions that the process can actually occur by accretion of phantom energy onto the wormholes and that it is stable and might occur in the global context of a multiverse model. We finally argue that the big trip does not contradict any holographic bounds on entropy and information

  3. Some notes on the big trip

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)]. E-mail: pedrogonzalez@mi.madritel.es

    2006-03-30

    The big trip is a cosmological process thought to occur in the future by which the entire universe would be engulfed inside a gigantic wormhole and might travel through it along space and time. In this Letter we discuss different arguments that have been raised against the viability of that process, reaching the conclusions that the process can actually occur by accretion of phantom energy onto the wormholes and that it is stable and might occur in the global context of a multiverse model. We finally argue that the big trip does not contradict any holographic bounds on entropy and information.

  4. Scheme of substations: circuit breakers topology; El esquema de S.E.: interruptor y medio y algunas variantes del mismo, a la luz de la gestion privada de instalaciones de servicio publico

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Maximo B. [Sade Skanska S.A. (Argentina)

    2001-07-01

    This work approaches a topological scheme applicable for the entrance circuit breakers which are used in high voltage substations and also in substations from the rated voltage class of 115 Kv by many countries. It is a safe scheme due to providing a double connection for the feeder cables and more economical than the double circuit breakers option. Nevertheless, the scheme has some restrictions as follows: a) The premises of continuity are not accomplished in small substations b) It is possible to occur a responsibility conflict in relation to the main circuit breaker. In the private administration of public service facilities multiples jurisdictions can appear which require well defined limits, and the penalties due to outages can be minimized.

  5. 76 FR 24358 - Airworthiness Directives; Dassault-Aviation Model FALCON 7X Airplanes

    Science.gov (United States)

    2011-05-02

    ...-wheels (WOW) proximity sensor wiring, both circuit breakers that supply power to that wiring will trip, causing simultaneous de-power of all WOW proximity sensors of that part of the system. The loss of the corresponding WOW information would lead to untimely inhibition of warnings that could compromise the pilot...

  6. Switchgear obsolescence

    International Nuclear Information System (INIS)

    Irish, C.S.

    2004-01-01

    As discussed in many forums, the global nuclear industry is struggling with many equipment issues, the foremost being obsolescence. The electrical distribution of a nuclear power plant is vital to plant safety and obviously to generation of electricity. Low and medium voltage breakers independent of OEM are becoming or are already obsolete in very large and alarming numbers. The obsolescence of the breakers causes the routine maintenance and overhauls to become very expensive and time consuming or not even possible at all. This is caused by the parts needed for the maintenance and overhauls to either not be available or to have very expensive prices and long lead times. The end result is that the overall switchgear reliability is greatly reduced due to nuisance trips, increased maintenance surveillance and breakers not being maintained with the frequency as needed. A lot of pressure is put on plant personnel to increase the reliability of the switchgear in the most cost effective manner. This paper will discuss using switchgear breaker replacements to improve the overall switchgear reliability. Whether the switchgear is 'safety related' or 'non-safety related' there is significant incentive to make as little field changes as necessary to improve the reliability. Replacement breakers achieve this goal. Replacement breakers are installed into the existing switchgear with little to no field changes. 600V, 5kV and 15kV breaker replacements are discussed with examples. (author)

  7. RETRAN analysis of San Onofre Unit 2 turbine trip from 100% power

    International Nuclear Information System (INIS)

    Ting, Y.P.

    1985-01-01

    During the San Onofre Nuclear Generating Station Unit (SONGS 2) startup test, the plant experienced a turbine trip from 100% power on June 16, 1983. The trip was initiated by the condenser pressure switch malfunctioning. The plant computers were operating and recorded many plant key parameters. The resulting trip behaved as if it has been manually initiated and it was considered equivalent to a preplanned turbine trip test. A RETRAN-02 model was developed to simulate the SONGS 2 June 16 turbine trip event. The RETRAN analysis of the trip is a continuing effort of in-house SONGS 2 RETRAN model development to benchmark the calculations against the plant startup test data. The overall agreement between measured data and the RETRAN calculations was very good, providing confidence in the capability of the model and the RETRAN program. Comparative data are presented

  8. WIPP site and vicinity geological field trip

    International Nuclear Information System (INIS)

    Chaturvedi, L.

    1980-10-01

    The Environmental Evaluation Group is conducting an assessment of the radiological health risks to people from the Waste Isolation Pilot Plant. As a part of this work, EEG is making an effort to improve the understanding of those geological issues concerning the WIPP site which may affect the radiological consequences of the proposed repository. One of the important geological issues to be resolved is the timing and the nature of the dissolution processes which may have affected the WIPP site. EEG organized a two-day conference of geological scientists, on January 17-18, 1980. On the basis of the January conference and the June field trip, EEG has formed the following conclusions: (1) it has not been clearly established that the site or the surrounding area has been attacked by deep dissolution to render it unsuitable for the nuclear waste pilot repository; (2) the existence of an isolated breccia pipe at the site unaccompanied by a deep dissolution wedge, is a very remote possibility; (3) more specific information about the origin and the nature of the brine reservoirs is needed. An important question that should be resolved is whether each encounter with artesian brine represents a separate pocket or whether these occurrences are interconnected; (4) Anderson has postulated a major tectonic fault or a fracture system at the Basin margin along the San Simon Swale; (5) the area in the northern part of the WIPP site, identified from geophysical and bore hole data as the disturbed zone, should be further investigated to cleary understand the nature and significance of this structural anomaly; and (6) a major drawback encountered during the discussions of geological issues related to the WIPP site is the absence of published material that brings together all the known information related to a particular issue

  9. Trip attraction rates of shopping centers in Northern New Castle County, Delaware.

    Science.gov (United States)

    2004-07-01

    This report presents the trip attraction rates of the shopping centers in Northern New : Castle County in Delaware. The study aims to provide an alternative to ITE Trip : Generation Manual (1997) for computing the trip attraction of shopping centers ...

  10. Hybrid Intelligent Warning System for Boiler tube Leak Trips

    Directory of Open Access Journals (Sweden)

    Singh Deshvin

    2017-01-01

    Full Text Available Repeated boiler tube leak trips in coal fired power plants can increase operating cost significantly. An early detection and diagnosis of boiler trips is essential for continuous safe operations in the plant. In this study two artificial intelligent monitoring systems specialized in boiler tube leak trips have been proposed. The first intelligent warning system (IWS-1 represents the use of pure artificial neural network system whereas the second intelligent warning system (IWS-2 represents merging of genetic algorithms and artificial neural networks as a hybrid intelligent system. The Extreme Learning Machine (ELM methodology was also adopted in IWS-1 and compared with traditional training algorithms. Genetic algorithm (GA was adopted in IWS-2 to optimize the ANN topology and the boiler parameters. An integrated data preparation framework was established for 3 real cases of boiler tube leak trip based on a thermal power plant in Malaysia. Both the IWSs were developed using MATLAB coding for training and validation. The hybrid IWS-2 performed better than IWS-1.The developed system was validated to be able to predict trips before the plant monitoring system. The proposed artificial intelligent system could be adopted as a reliable monitoring system of the thermal power plant boilers.

  11. Pre-Trip Notification Database (PTNS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The PTNS contains pre-trip notification data from vessels participating in the Northeast Multispecies groundfish fishery from 2010 to present and the Longfin squid...

  12. A Novel Trip Coverage Index for Transit Accessibility Assessment Using Mobile Phone Data

    Directory of Open Access Journals (Sweden)

    Zhengyi Cai

    2017-01-01

    Full Text Available Transit accessibility is an important measure on the service performance of transit systems. To assess whether the public transit service is well accessible for trips of specific origins, destinations, and origin-destination (OD pairs, a novel measure, the Trip Coverage Index (TCI, is proposed in this paper. TCI considers both the transit trip coverage and spatial distribution of individual travel demands. Massive trips between cellular base stations are estimated by using over four-million mobile phone users. An easy-to-implement method is also developed to extract the transit information and driving routes for millions of requests. Then the trip coverage of each OD pair is calculated. For demonstrative purposes, TCI is applied to the transit network of Hangzhou, China. The results show that TCI represents the better transit trip coverage and provides a more powerful assessment tool of transit quality of service. Since the calculation is based on trips of all modes, but not only the transit trips, TCI offers an overall accessibility for the transit system performance. It enables decision makers to assess transit accessibility in a finer-grained manner on the individual trip level and can be well transformed to measure transit services of other cities.

  13. CNMI Commercial Purchases (Trip Ticket)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Commonwealth of Northern Mariana Islands (CNMI), Division of Fish and Wildlife (DFW) collects 'Trip Ticket' or purchase invoice data from vendors that buy fish...

  14. Transient Studies in Large Offshore Wind Farms, Employing Detailed Circuit Breaker Representation

    DEFF Research Database (Denmark)

    Glasdam, Jakob Bærholm; Bak, Claus Leth; Hjerrild, Jesper

    2012-01-01

    in order to ensure reliable switching operations. Transient measurement results in an OWF are compared with simulation results in PSCAD EMTDC and DigSILENT Power Factory. A user-defined model of the vacuum circuit breaker (VCB) is included in both tools, capable of simulating multiple prestrikes during...... greatly improves the simulation results, whereas little improvement is found in DigSILENT. Based on the transient study it is found that the simulated SOV can be up to 60% higher at the sending end when using the detailed VCB representation compared to the built-in switch, which emphasises the need...

  15. Transcription regulator TRIP-Br2 mediates ER stress-induced brown adipocytes dysfunction.

    Science.gov (United States)

    Qiang, Guifen; Whang Kong, Hyerim; Gil, Victoria; Liew, Chong Wee

    2017-01-09

    In contrast to white adipose tissue, brown adipose tissue (BAT) is known to play critical roles for both basal and inducible energy expenditure. Obesity is associated with reduction of BAT function; however, it is not well understood how obesity promotes BAT dysfunction, especially at the molecular level. Here we show that the transcription regulator TRIP-Br2 mediates ER stress-induced inhibition of lipolysis and thermogenesis in BAT. Using in vitro, ex vivo, and in vivo approaches, we demonstrate that obesity-induced inflammation upregulates brown adipocytes TRIP-Br2 expression via the ER stress pathway and amelioration of ER stress in mice completely abolishes high fat diet-induced upregulation of TRIP-Br2 in BAT. We find that increased TRIP-Br2 significantly inhibits brown adipocytes thermogenesis. Finally, we show that ablation of TRIP-Br2 ameliorates ER stress-induced inhibition on lipolysis, fatty acid oxidation, oxidative metabolism, and thermogenesis in brown adipocytes. Taken together, our current study demonstrates a role for TRIP-Br2 in ER stress-induced BAT dysfunction, and inhibiting TRIP-Br2 could be a potential approach for counteracting obesity-induced BAT dysfunction.

  16. Trip Generations at “Polyclinic” Land Use Type in Johor Bahru, Malaysia

    OpenAIRE

    Ahmed, Ishtiaque; Abdulrahman, Suleiman; Hainin, Mohd Rosli; Hassan, Sitti Asmah

    2014-01-01

    Transportation planners need to estimate the trip generations of different land use types in the travel demand forecasting process. The Trip Generation Manual of Malaysia, similar to the Trip Generation Manual of the Institute of Transportation Engineers, USA, provides the trip generation rate at “Polyclinics” as a function of the Gross Floor Area. However, the data for this rate have no line of best fit resulting in the lack of confidence in the prediction. This study considered ten location...

  17. Teachers as Secondary Players: Involvement in Field Trips to Natural Environments

    Science.gov (United States)

    Alon, Nirit Lavie; Tal, Tali

    2017-08-01

    This study focused on field trips to natural environments where the teacher plays a secondary role alongside a professional guide. We investigated teachers' and field trip guides' views of the teacher's role, the teacher's actual function on the field trip, and the relationship between them. We observed field trips, interviewed teachers and guides, and administered questionnaires. We found different levels of teacher involvement, ranging from mainly supervising and giving technical help, to high involvement especially in the cognitive domain and sometimes in the social domain. Analysis of students' self-reported outcomes showed that the more students believe their teachers are involved, the higher the self-reported learning outcomes.

  18. Make My Trip Count 2015

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Make My Trip Count (MMTC) commuter survey, conducted in September and October 2015 by GBA, the Pittsburgh 2030 District, and 10 other regional transportation...

  19. Trip setpoint analysis for the reactor protection system of an advanced integral reactor

    International Nuclear Information System (INIS)

    Yang, Soo Hyung; Kim, Soo Hyung; Chung, Young Jong; Zee, Sung Quun

    2007-01-01

    The trip setpoints for the reactor protection system of a 65-MWt advanced integral reactor have been analyzed through sensitivity evaluations by using the Transients and Setpoint Simulation/System-integrated Modular Reactor code. In the analysis, an inadvertent control rod withdrawal event has been considered as an initiating event because this event results in the worst consequences from the viewpoint of the minimum critical heat flux ratio and its consequences are considerably affected by the trip setpoints. Sensitivity evaluations have been performed by changing the trip setpoints for the ceiling of a variable overpower trip (VOPT) function and the pressure of a high pressurizer pressure trip function. Analysis results show that a VOPT function is an effective means to satisfy the acceptance criteria as the control rod rapidly withdraws: on the other hand, a high pressurizer pressure trip function is an essential measure to preserve the safety margin in the case of a slow withdrawal of the control rod because a reactor trip by a VOPT function does not occur in this case. It is also shown that the adoptions of 122.2% of the rated core power and 16.25 MPa as the trip setpoint for the ceiling of a VOPT function and the pressure of a high pressurizer pressure trip function are good selections to satisfy the acceptance criteria

  20. Deliberation of arc plasma characteristics according to experimental results in a typical gas circuit-breaker

    International Nuclear Information System (INIS)

    Borghei, M.

    2005-01-01

    One of the industrial plasma applications is in the gas circuit breakers (GCB) and switching processes. During GCB operation and opening of its two contacts, current flows through of the inter-electrode medium (generally SF 6 or its mixture) and electric arc forms from the plasma that has been created between the contacts. The electric arc is a self-sustained discharge having low voltage drop and able to support great amplitudes of current. The technical basis of circuit breaker is: initiating arc plasma, flowing a large current, cooling it effectively to avoid re-ignition, and finally the transition from a well-conducting medium into insulating gas space in a very short time interval. In other words, for a successful interruption we need to know about power brought to the arc and that of removed. In this paper an attempt has been made to study, characterize and understand some arc behaviors such as arc conductance and its changes according to recorded current and voltage traces experimentally. From physical point of view, there are different phenomena that affect on arc behavior. According to methodology used here, we tried to understand some of arc behavior from experimental results and finally we extract some arc parameters. (author)

  1. Flat Plate Boundary Layer Stimulation Using Trip Wires and Hama Strips

    Science.gov (United States)

    Peguero, Charles; Henoch, Charles; Hrubes, James; Fredette, Albert; Roberts, Raymond; Huyer, Stephen

    2017-11-01

    Water tunnel experiments on a flat plate at zero angle of attack were performed to investigate the effect of single roughness elements, i.e., trip wires and Hama strips, on the transition to turbulence. Boundary layer trips are traditionally used in scale model testing to force a boundary layer to transition from laminar to turbulent flow at a single location to aid in scaling of flow characteristics. Several investigations of trip wire effects exist in the literature, but there is a dearth of information regarding the influence of Hama strips on the flat plate boundary layer. The intent of this investigation is to better understand the effects of boundary layer trips, particularly Hama strips, and to investigate the pressure-induced drag of both styles of boundary layer trips. Untripped and tripped boundary layers along a flat plate at a range of flow speeds were characterized with multiple diagnostic measurements in the NUWC/Newport 12-inch water tunnel. A wide range of Hama strip and wire trip thicknesses were used. Measurements included dye flow visualization, direct skin friction and parasitic drag force, boundary layer profiles using LDV, wall shear stress fluctuations using hot film anemometry, and streamwise pressure gradients. Test results will be compared to the CFD and boundary layer model results as well as the existing body of work. Conclusions, resulting in guidance for application of Hama strips in model scale experiments and non-dimensional predictions of pressure drag will be presented.

  2. Seismic damage sensing of bridge structures with TRIP reinforcement steel bars

    Science.gov (United States)

    Adachi, Yukio; Unjoh, Shigeki

    2001-07-01

    Intelligent reinforced concrete structures with transformation-induced-plasticity (TRIP) steel rebars that have self-diagnosis function are proposed. TRIP steel is special steel with Fe-Cr based formulation. It undergoes a permanent change in crystal structure in proportion to peak strain. This changes from non-magnetic to magnetic steel. By using the TRIP steel rebars, the seismic damage level of reinforced concrete structures can be easily recognized by measuring the residual magnetic level of the TRIP rebars, that is directly related to the peak strain during a seismic event. This information will be most helpful for repairing the damaged structures. In this paper, the feasibility of the proposed intelligent reinforced concrete structure for seismic damage sensing is experimentally studied. The relation among the damage level, peak strain of rebars, and residual magnetic level of rebars of reinforced concrete beams implemented with TRIP steel bars was experimentally studied. As the result of this study, this intelligent structure can diagnose accumulated strain/damage anticipated during seismic event.

  3. Recommendations for Planning and Managing International Short-term Pharmacy Service Trips.

    Science.gov (United States)

    Johnson, Kalin L; Alsharif, Naser Z; Rovers, John; Connor, Sharon; White, Nicole D; Hogue, Michael D

    2017-03-25

    International pharmacy service trips by schools and colleges of pharmacy allow students to provide health care to medically underserved areas. A literature review (2000-2016) in databases and Internet searches with specific keywords or terms was performed to assess current practices to establish and maintain successful pharmacy service trips. Educational documents such as syllabi were obtained from pharmacy programs and examined. A preliminary draft was developed and authors worked on sections of interest and expertise. Considerations and current recommendations are provided for the key aspects of the home institution and the host country requirements for pharmacy service trips based on findings from a literature search and the authors' collective, extensive experience. Evaluation of the trip and ethical considerations are also discussed. This article serves as a resource for schools and colleges of pharmacy that are interested in the development of new pharmacy service trips and provides key considerations for continuous quality improvement of current or future activities.

  4. Trip-oriented travel time prediction (TOTTP) with historical vehicle trajectories

    Science.gov (United States)

    Xu, Tao; Li, Xiang; Claramunt, Christophe

    2018-06-01

    Accurate travel time prediction is undoubtedly of importance to both traffic managers and travelers. In highly-urbanized areas, trip-oriented travel time prediction (TOTTP) is valuable to travelers rather than traffic managers as the former usually expect to know the travel time of a trip which may cross over multiple road sections. There are two obstacles to the development of TOTTP, including traffic complexity and traffic data coverage.With large scale historical vehicle trajectory data and meteorology data, this research develops a BPNN-based approach through integrating multiple factors affecting trip travel time into a BPNN model to predict trip-oriented travel time for OD pairs in urban network. Results of experiments demonstrate that it helps discover the dominate trends of travel time changes daily and weekly, and the impact of weather conditions is non-trivial.

  5. The development of cause analysis system for CPCS trip using the rule-base deduction

    International Nuclear Information System (INIS)

    Park, Hee Seok; Kim, Dong Hoon; Seo, Ho Joon; Koo, In Soo; Park, Suk Joon

    1992-01-01

    The Core Protection Calculator System(CPCS) was developed to initiate a Reactor Trip under the circumstance of certain transients by Combustion Engineering Company. The major function of the CPCS is to generate contact outputs for the Departure from Nucleate Boiling Ratio(DNBR) Trip and Local Power Density(LPD) Trip. But in CPCS the trip causes can not be identified, only trip status is displayed. It may take much time and efforts for plant operator to analyse the trip causes of CPCS. So, the Cause Analysis System for CPCS(CASCPCS) has been developed using the rule-base deduction method to aid the operators in Nuclear Power Plant

  6. Evaluation of the root cause for MSR high level trip in Maanshan

    International Nuclear Information System (INIS)

    Liao, L.-Y.; Ferng, Y.-M.; Jange, S.J.; Ko, C.M.

    2004-01-01

    Reactor trip due to Moisture Separator Reheater (MSR) high water level has been a long time issue for Maanshan nuclear power plant. The operating experience shows that there are five reactor trips due to MSR high water level. Four out of the five reactor trips are generated when Combined Intermediate valve (CIV) no. 1 is closed during CIV closure test. The fifth reactor trip occurs when the reactor power is increasing from 99% to 100%. An extensive root cause analysis has been performed by Taipower Company. It is concluded that the water accumulated in the cross under leg between the exhaust of high pressure turbine and the inlet of MSR was the water source contributing to the MSR high level trip. Although, Maanshan does not have similar trip after the root cause analysis, it is interested to evaluate the proposed root cause from thermal hydraulic point of view. It is also hoped that some useful guidelines can be established. This paper includes a description of the scenario of reactor trips, a summary of the root cause analysis done by Taipower Company, an examination of possible mechanisms, an identification of key parameters and a presentation of major findings. In addition, the applicability of RELAP5/MOD3 under this condition is discussed. (author)

  7. An approach of raising the low power reactor trip block (P-7) in Maanshan Power Plant

    International Nuclear Information System (INIS)

    Wang, L.C.

    1984-01-01

    The technical specification for the Maanshan Nuclear Power Station (FSAR Table 16.2.2-3) requires that with an increasing reactor power level above the setpoint of low power reactor trip block (P-7), a turbine trip shall initiate a reactor trip. This anticipatory reactor trip on turbine trip prevents the pressurizer PORV from openning during turbine trip event. In order to reduce unnecessary reactor trip due to turbine trip on low reactor power level during Maanshan start-up stage, Taiwan Power Company performed a transient analysis for turbine trip event by using RETRAN code. The highest reactor power level at which a turbine trip will not open the pressurizer PORV is searched. The results demonstrated that this power level can be increased from the original value-10% of the rated thermal power-to about 48% of the rated thermal power

  8. The LEP RF Trip and Beam Loss Diagnostics System

    CERN Document Server

    Arnaudon, L; Beetham, G; Ciapala, Edmond; Juillard, J C; Olsen, R

    2002-01-01

    During the last years of operation the number of operationally independent RF stations distributed around LEP reached a total of 40. A serious difficulty when running at high energy and high beam intensities was to establish cause and effect in beam loss situations, where the trip of any single RF station would result in beam loss, rapidly producing further multiple RF station trips. For the last year of operation a fast post-mortem diagnostics system was developed to allow precise time-stamping of RF unit trips and beam intensity changes. The system was based on eight local DSP controlled fast acquisition and event recording units, one in each RF sector, connected to critical RF control signals and fast beam intensity monitors and synchronised by GPS. The acquisition units were armed and synchronised at the start of each fill. At the end of the fill the local time-stamped RF trip and beam intensity change history tables were recovered, events ordered and the results stored in a database for subsequent analys...

  9. Addressing legal and political barriers to global pharmaceutical access: options for remedying the impact of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) and the imposition of TRIPS-plus standards.

    Science.gov (United States)

    Cohen-Kohler, Jillian Clare; Forman, Lisa; Lipkus, Nathaniel

    2008-07-01

    Despite myriad programs aimed at increasing access to essential medicines in the developing world, the global drug gap persists. This paper focuses on the major legal and political constraints preventing implementation of coordinated global policy solutions - particularly, the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) and bilateral and regional free trade agreements. We argue that several policy and research routes should be taken to mitigate the restrictive impact of TRIPS and TRIPS-plus rules, including greater use of TRIPS flexibilities, advancement of human rights, and an ethical framework for essential medicines distribution, and a broader campaign that debates the legitimacy of TRIPS and TRIPS-plus standards themselves.

  10. Relay Coordination in the Protection of Radially-Connected Power ...

    African Journals Online (AJOL)

    Protective relays detect intolerable or unwanted conditions within an assigned area, and then trip or open one or more circuit breakers to isolate the problem area before it can damage or otherwise interfere with the eective operation of the rest of the power system. It often happens that a substation feeder relay and ...

  11. Trip time prediction in mass transit companies. A machine learning approach

    OpenAIRE

    João M. Moreira; Alípio Jorge; Jorge Freire de Sousa; Carlos Soares

    2005-01-01

    In this paper we discuss how trip time prediction can be useful foroperational optimization in mass transit companies and which machine learningtechniques can be used to improve results. Firstly, we analyze which departmentsneed trip time prediction and when. Secondly, we review related work and thirdlywe present the analysis of trip time over a particular path. We proceed by presentingexperimental results conducted on real data with the forecasting techniques wefound most adequate, and concl...

  12. Determination of Biology Department Students' Past Field Trip Experiences and Examination of Their Self-Efficacy Beliefs in Planning and Organising Educational Field Trips

    Science.gov (United States)

    Bozdogan, Aykut Emre

    2015-01-01

    The purpose of this study is to determine the past field trip experiences of pre-service teachers who are graduates of Faculty of Sciences, Department of Biology and who had pedagogical formation training certificate and to examine their self-efficacy beliefs in planning and organizing field trips with regard to different variables. The study was…

  13. Does ignoring multidestination trips in the travel cost method cause a systematic bias?

    NARCIS (Netherlands)

    Kuosmanen, T.K.; Nillesen, E.E.M.; Wesseler, J.H.H.

    2004-01-01

    The present paper demonstrates that treating multidestination trips (MDT) as single-destination trips does not involve any systematic upward or downward bias in consumer surplus (CS) estimates because the direct negative effect of a price increase (treating MDT as a single-destination trip) is

  14. Effects of alagebrium, an advanced glycation endproduct breaker, on exercise tolerance and cardiac function in patients with chronic heart failure

    NARCIS (Netherlands)

    Hartog, Jasper W. L.; Willemsen, Suzan; van Veldhuisen, Dirk J.; Posma, Jan L.; van Wijk, Leen M.; Hummel, Yoran M.; Hillege, Hans L.; Voors, Adriaan A.

    Aims Advanced glycation endproducts (AGEs) have been associated with the development and progression of chronic heart failure (CHF). Advanced glycation endproducts-crosslink breakers might be of benefit in HF, but only small-scale and uncontrolled data are available. Our aim was to conduct a

  15. The AAA+ ATPase TRIP13 remodels HORMA domains through N-terminal engagement and unfolding

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Qiaozhen; Kim, Dong Hyun; Dereli, Ihsan; Rosenberg, Scott C.; Hagemann, Goetz; Herzog, Franz; Tóth, Attila; Cleveland, Don W.; Corbett, Kevin D.

    2017-06-28

    Proteins of the conserved HORMA domain family, including the spindle assembly checkpoint protein MAD2 and the meiotic HORMADs, assemble into signaling complexes by binding short peptides termed “closure motifs”. The AAA+ ATPase TRIP13 regulates both MAD2 and meiotic HORMADs by disassembling these HORMA domain–closure motif complexes, but its mechanisms of substrate recognition and remodeling are unknown. Here, we combine X-ray crystallography and crosslinking mass spectrometry to outline how TRIP13 recognizes MAD2 with the help of the adapter protein p31comet. We show that p31comet binding to the TRIP13 N-terminal domain positions the disordered MAD2 N-terminus for engagement by the TRIP13 “pore loops”, which then unfold MAD2 in the presence of ATP. N-terminal truncation of MAD2 renders it refractory to TRIP13 action in vitro, and in cells causes spindle assembly checkpoint defects consistent with loss of TRIP13 function. Similar truncation of HORMAD1 in mouse spermatocytes compromises its TRIP13-mediated removal from meiotic chromosomes, highlighting a conserved mechanism for recognition and disassembly of HORMA domain–closure motif complexes by TRIP13.

  16. Investigating Characteristics of N2, CO2 and CF3I in Contrast to High Current Arcs in Circuit Breakers to Choose a Suitable Substitute for SF6

    Directory of Open Access Journals (Sweden)

    V. Abbasi

    2017-09-01

    Full Text Available Specific and sensitive operation of circuit breakers makes an individual position for them in power networks. Circuit breakers are at the central gravity of variations and execution operations. Therefore, an optimum operation is the main reason to investigate about new gases to be used in MV and HV circuit breakers instead of SF6. The arc process has enormous complexity because of hydrodynamic and electromagnetic combination equations, and that is the exact reason why most of the previous simulations were processed in two-dimension analysis. But, in this paper a three-dimension simulation with sufficient results has been fully discussed. Different evaluations on the other gases have taken under study in order to find a suitable substitute instead of SF6 gas, which can also bring an optimum operation for the breakers and can be even friendly with the environment. The simulations have been carried out based on the finite element method (FEM and magneto-hydrodynamic equations. A three-dimension model under the transient state has been chosen in the simulations to find a feasible substitute for SF6 gas. The main factors of the analysis are threefold as follows: arc temperature on the different regions, the cooling ability and arc resistance. CO2, CF3I and N2 are nominated to substitute the SF6 gas and their effects on cooling ability, nozzle evaporation, contacts erosion and arc resistance will be discussed.

  17. Chelation: A Fundamental Mechanism of Action of AGE Inhibitors, AGE Breakers, and Other Inhibitors of Diabetes Complications

    Energy Technology Data Exchange (ETDEWEB)

    Nagai, Rhoji; Murray, David B.; Metz, Thomas O.; Baynes, John

    2012-03-01

    Advanced glycation or glycoxidation end-products (AGE) increase in tissue proteins with age, and their rate of accumulation is increased in diabetes, nephropathy and inflammatory diseases. AGE inhibitors include a range of compounds that are proposed to act by trapping carbonyl and dicarbonyl intermediates in AGE formation. However, some among the newer generation of AGE inhibitors lack reactive functional groups that would trap reaction intermediates, indicating an alternative mechanism of action. We propose that AGE inhibitors function primarily as chelators, inhibiting metal-catalyzed oxidation reactions. The AGE-inhibitory activity of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers is also consistent with their chelating activity. Finally, compounds described as AGE breakers, or their hydrolysis products, also have strong chelating activity, suggesting that these compounds also act through their chelating activity. We conclude that chelation is the common, and perhaps the primary, mechanism of action of AGE inhibitors and breakers, and that chronic, mild chelation therapy should prove useful in treatment of diabetes and age-related diseases characterized by oxidative stress, inflammation and increased chemical modification of tissue proteins by advanced glycoxidation and lipoxidation end-products.

  18. TRIP-Br2 promotes oncogenesis in nude mice and is frequently overexpressed in multiple human tumors.

    Science.gov (United States)

    Cheong, Jit Kong; Gunaratnam, Lakshman; Zang, Zhi Jiang; Yang, Christopher M; Sun, Xiaoming; Nasr, Susan L; Sim, Khe Guan; Peh, Bee Keow; Rashid, Suhaimi Bin Abdul; Bonventre, Joseph V; Salto-Tellez, Manuel; Hsu, Stephen I

    2009-01-20

    Members of the TRIP-Br/SERTAD family of mammalian transcriptional coregulators have recently been implicated in E2F-mediated cell cycle progression and tumorigenesis. We, herein, focus on the detailed functional characterization of the least understood member of the TRIP-Br/SERTAD protein family, TRIP-Br2 (SERTAD2). Oncogenic potential of TRIP-Br2 was demonstrated by (1) inoculation of NIH3T3 fibroblasts, which were engineered to stably overexpress ectopic TRIP-Br2, into athymic nude mice for tumor induction and (2) comprehensive immunohistochemical high-throughput screening of TRIP-Br2 protein expression in multiple human tumor cell lines and human tumor tissue microarrays (TMAs). Clinicopathologic analysis was conducted to assess the potential of TRIP-Br2 as a novel prognostic marker of human cancer. RNA interference of TRIP-Br2 expression in HCT-116 colorectal carcinoma cells was performed to determine the potential of TRIP-Br2 as a novel chemotherapeutic drug target. Overexpression of TRIP-Br2 is sufficient to transform murine fibroblasts and promotes tumorigenesis in nude mice. The transformed phenotype is characterized by deregulation of the E2F/DP-transcriptional pathway through upregulation of the key E2F-responsive genes CYCLIN E, CYCLIN A2, CDC6 and DHFR. TRIP-Br2 is frequently overexpressed in both cancer cell lines and multiple human tumors. Clinicopathologic correlation indicates that overexpression of TRIP-Br2 in hepatocellular carcinoma is associated with a worse clinical outcome by Kaplan-Meier survival analysis. Small interfering RNA-mediated (siRNA) knockdown of TRIP-Br2 was sufficient to inhibit cell-autonomous growth of HCT-116 cells in vitro. This study identifies TRIP-Br2 as a bona-fide protooncogene and supports the potential for TRIP-Br2 as a novel prognostic marker and a chemotherapeutic drug target in human cancer.

  19. Medical and pharmacy student concerns about participating on international service-learning trips

    OpenAIRE

    Chuang, Chih; Khatri, Siddique H.; Gill, Manpal S.; Trehan, Naveen; Masineni, Silpa; Chikkam, Vineela; Farah, Guillaume G.; Khan, Amber; Levine, Diane L.

    2015-01-01

    Background International Service Learning Trips (ISLT) provide health professional students the opportunity to provide healthcare, under the direction of trained faculty, to underserved populations in developing countries. Despite recent increases in international service learning trips, there is scant literature addressing concerns students have prior to attending such trips. This study focuses on identifying concerns before and after attending an ISLT and their impact on students. Methods A...

  20. Power Trip Set-points of Reactor Protection System for New Research Reactor

    International Nuclear Information System (INIS)

    Lee, Byeonghee; Yang, Soohyung

    2013-01-01

    This paper deals with the trip set-point related to the reactor power considering the reactivity induced accident (RIA) of new research reactor. The possible scenarios of reactivity induced accidents were simulated and the effects of trip set-point on the critical heat flux ratio (CHFR) were calculated. The proper trip set-points which meet the acceptance criterion and guarantee sufficient margins from normal operation were then determined. The three different trip set-points related to the reactor power are determined based on the RIA of new research reactor during FP condition, over 0.1%FP and under 0.1%FP. Under various reactivity insertion rates, the CHFR are calculated and checked whether they meet the acceptance criterion. For RIA at FP condition, the acceptance criterion can be satisfied even if high power set-point is only used for reactor trip. Since the design of the reactor is still progressing and need a safety margin for possible design changes, 18 MW is recommended as a high power set-point. For RIA at 0.1%FP, high power setpoint of 18 MW and high log rate of 10%pp/s works well and acceptance criterion is satisfied. For under 0.1% FP operations, the application of high log rate is necessary for satisfying the acceptance criterion. Considering possible decrease of CHFR margin due to design changes, the high log rate is suggested to be 8%pp/s. Suggested trip set-points have been identified based on preliminary design data for new research reactor; therefore, these trip set-points will be re-established by considering design progress of the reactor. The reactor protection system (RPS) of new research reactor is designed for safe shutdown of the reactor and preventing the release of radioactive material to environment. The trip set point of RPS is essential for reactor safety, therefore should be determined to mitigate the consequences from accidents. At the same time, the trip set-point should secure margins from normal operational condition to avoid

  1. Methods for analysis of passenger trip performance in a complex networked transportation system

    Science.gov (United States)

    Wang, Danyi

    2007-12-01

    The purpose of the Air Transportation System (ATS) is to provide safe and efficient transportation service of passengers and cargo. The on-time performance of a passenger's trip is a critical performance measurement of the Quality of Service (QOS) provided by any Air Transportation System. QOS has been correlated with airline profitability, productivity, customer loyalty and customer satisfaction (Heskett et al. 1994). Btatu and Barnhart have shown that official government and airline on-time performance metrics (i.e. flight-centric measures of air transportation) fail to accurately reflect the passenger experience (Btatu and Barnhart, 2005). Flight-based metrics do not include the trip delays accrued by passengers who were re-booked due to cancelled flights or missed connections. Also, flight-based metrics do not quantify the magnitude of the delay (only the likelihood) and thus fails to provide the consumer with a useful assessment of the impact of a delay. Passenger-centric metrics have not been developed because of the unavailability of airline proprietary data, which is also protected by anti-trust collusion concerns and civil liberty privacy restrictions. Moveover, the growth of the ATS is trending out of the historical range. The objectives of this research were to (1) estimate ATS-wide passenger trip delay using publicly accessible flight data, and (2) investigate passenger trip dynamics out of the range of historical data by building a passenger flow simulation model to predict impact on passenger trip time given anticipated changes in the future. The first objective enables researchers to conduct historical analysis on passenger on-time performance without proprietary itinerary data, and the second objective enables researchers to conduct experiments outside the range of historic data. The estimated passenger trip delay was for 1,030 routes between the 35 busiest airports in the United States in 2006. The major findings of this research are listed as

  2. A new generation of medium-voltage switchboards and circuit-breakers; Eine neue Generation von Mittelspannungsschaltanlagen und -leistungsschaltern

    Energy Technology Data Exchange (ETDEWEB)

    Saemann, D.; Weichert, R.; Werner, S. [Siemens AG, Erlangen (Germany). Bereich Energieuebertragung und -verteilung

    1998-04-06

    Todays market and the trend towards globalization of business both call for new products. The authors describe the new generation of medium-voltage switchgears and circuit-breakers, along with the benefit they bring for customers. (orig./RHM) [Deutsch] Der Markt und die Globalisierung des Geschaeftes fordern neue Produkte. Die Verfasser beschreiben die neue Generation von Mittelspannungsschaltanlagen und -schaltern sowie deren Nutzen fuer die Anwender. (orig./RHM)

  3. Risk assessment to determine the advisability of seismic trip systems

    International Nuclear Information System (INIS)

    Cummings, G.E.; Wells, J.E.

    1977-01-01

    Seismic trip (scram) systems have been used for many years on certain research, test, and production reactors, but not on commercial power reactors. An assessment is made of the risks associated with the presence and absence of such trip systems on power reactors. An attempt was made to go beyond the reactor per se and to consider the risks to society as a whole; for example, the advantages of tripping to avoid an earthquake-caused accident were weighed against the disadvantages associated with interrupting electric power in a time when it would be needed for emergency services. The comparative risk assessment was performed by means of fault tree analysis

  4. Analysis of reactor trips involving balance-of-plant failures

    International Nuclear Information System (INIS)

    Seth, S.; Skinner, L.; Ettlinger, L.; Lay, R.

    1986-01-01

    The relatively high frequency of plant transients leading to reactor trips at nuclear power plants in the US is of economic and safety concern to the industry. A majority of such transients is due to failures in the balance-of-plant (BOP) systems. As a part of a study conducted for the US Nuclear Regulatory Commission, Mitre has carried out a further analysis of the BOP failures associated with reactor trips. The major objectives of the analysis were to examine plant-to-plant variations in BOP-related trips, to understand the causes of failures, and to determine the extent of any associated safety system challenges. The analysis was based on the Licensee Event Reports submitted on all commercial light water reactors during the 2-yr period, 1984-1985

  5. Predictors of trips to food destinations

    Directory of Open Access Journals (Sweden)

    Kerr Jacqueline

    2012-05-01

    Full Text Available Abstract Background Food environment studies have focused on ethnic and income disparities in food access. Few studies have investigated distance travelled for food and did not aim to inform the geographic scales at which to study the relationship between food environments and obesity. Further, studies have not considered neighborhood design as a predictor of food purchasing behavior. Methods Atlanta residents (N = 4800 who completed a travel diary and reported purchasing or consuming food at one of five food locations were included in the analyses. A total of 11,995 food-related trips were reported. Using mixed modeling to adjust for clustering of trips by participants and households, person-level variables (e.g. demographics, neighborhood-level urban form measures, created in GIS, and trip characteristics (e.g. time of day, origin and destination were investigated as correlates of distance travelled for food and frequency of grocery store and fast food outlet trips. Results Mean travel distance for food ranged from 4.5 miles for coffee shops to 6.3 miles for superstores. Type of store, urban form, type of tour, day of the week and ethnicity were all significantly related to distance travelled for food. Origin and destination environment, type of tour, day of week, age, gender, income, ethnicity, vehicle access and obesity status were all significantly related to visiting a grocery store. Home neighborhood environment, day of week, type of tour, gender, income, education level, age, and obesity status were all significantly related to likelihood of visiting a fastfood outlet. Conclusions The present study demonstrated that people travel sizeable distances for food and this distance is related to urban. Results suggest that researchers need to employ different methods to characterize food environments than have been used to assess urban form in studies of physical activity. Food is most often purchased while traveling from locations other

  6. Decreasing emissions of a secondary lead smelter by installation of a battery breaker. Emissionsminderung einer Sekundaerbleihuette durch Integration einer Akkuschrott-Aufbereitung

    Energy Technology Data Exchange (ETDEWEB)

    Lamm, K F

    1986-11-01

    Dust and lead emissions of a secondary lead smelter mainly from the area of stockyards, handling, transport, charge preparing as well as the further treatment in rotary furnaces. A 60% decrease is obtained by compact assembling of covered battery stockyard, battery breaker and charge preparation and direct connection to the existing smelter area. The breaker itself contains a wet screen trommel and a filter press for separation of paste. The heavy-media sink-float-system has been replaced by dynamic water separation, which results in cleaner qualities of all fractions. In spite of a 100% wet separation plant, a bagfilter can be used with expected clean gas dust contents below 5 mg/m{sup 3} and below 2.5 mg Pb/m{sup 3}. Over a 2 years-period, dust and lead contents have been below 1 mg/m{sup 3}. (orig.) With 5 refs., 2 flowsheets, 10 figs.

  7. Estimations of radiation characteristics of spent fuel in reactors of nuclear submarines and the ice-breaker Lenin dumped near Novaya Zemlya

    International Nuclear Information System (INIS)

    Rubtsov, P.M.; Ruzhanskij, P.A.

    1996-01-01

    Calculations of radionuclide composition and radiation characteristics of actinides and fission products for the reactor spent nuclear fuel of the nuclear submarines and the ice-breaker Lenin dumped near Novaya Zemlya are calculated on the basis of the actual data on the regimes of operation of the above reactors. It is determined that the maximum total activity in 1995 in all reactor sections of the nuclear submarines is concentrated in the fuel (M = 261.9 kg, W = 2.75 GW x day) of the left reactor of the nuclear submarine APL-285 and constitutes 51.9 Ci for actinides and 1.68 x 10 4 Ci for fission products. The corresponding values for the dumped fuel (M = 856 kg, W = 14.2 GW x day) of the ice-breaker Lenin are equal to 3.9 x 10 3 and 5.22 x 10 4 Ci

  8. Field Trips and the Law.

    Science.gov (United States)

    Troy, Thomas D.; Schwaab, Karl E.

    1981-01-01

    Legal aspects of field trips are addressed, with special attention on planning and implementation aspects which warrant legal consideration. Suggestions are based on information obtained from studies which reviewed and analyzed court cases, with recommendations geared to lessen the likelihood that negligence suits will result if students sustain…

  9. Elastic tripping analysis of corroded stiffeners in stiffened plate with irregular surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Rahbarranji, Ahmad [AmirKabir University of Technology, Tehran (Iran, Islamic Republic of)

    2014-09-15

    Tripping of stiffeners is one of the buckling modes of stiffened panels which could rapidly lead to its catastrophic failure. Loss of thickness in the web and flange of stiffeners due to corrosion reduces elastic buckling strength. It is common practice to assume a uniform thickness reduction for corroded surfaces. To estimate the remaining strength of a corroded structure, a much higher level of accuracy is required since corroded surfaces are irregular. Finite element method is employed to analyze elastic tripping stress of corroded stiffeners with irregular surfaces. Comparing the results with elastic tripping stress of un-corroded stiffener, a reduction factor is introduced. It is found that for flat-bars and angle-bars the reduction factor increases by increasing corrosion loss; however, for tee-bars remains almost unchanged. Surface roughness has no significant effect on reduction of tripping Euler stress of angle-bars and flat-bars; however, it has an effect on reduction of tripping Euler stress of small flat-bars. For high values of corrosion loss, reduction of tripping Euler stress is higher in flat-bars than angle-bars. Corrosion at the mid-length or ends of flat-bars is more detrimental than full length. Corrosion at the ends of angle-bars is more detrimental than full length and mid-length.

  10. TRIP-Br2 promotes oncogenesis in nude mice and is frequently overexpressed in multiple human tumors

    Directory of Open Access Journals (Sweden)

    Peh Bee

    2009-01-01

    Full Text Available Abstract Background Members of the TRIP-Br/SERTAD family of mammalian transcriptional coregulators have recently been implicated in E2F-mediated cell cycle progression and tumorigenesis. We, herein, focus on the detailed functional characterization of the least understood member of the TRIP-Br/SERTAD protein family, TRIP-Br2 (SERTAD2. Methods Oncogenic potential of TRIP-Br2 was demonstrated by (1 inoculation of NIH3T3 fibroblasts, which were engineered to stably overexpress ectopic TRIP-Br2, into athymic nude mice for tumor induction and (2 comprehensive immunohistochemical high-throughput screening of TRIP-Br2 protein expression in multiple human tumor cell lines and human tumor tissue microarrays (TMAs. Clinicopathologic analysis was conducted to assess the potential of TRIP-Br2 as a novel prognostic marker of human cancer. RNA interference of TRIP-Br2 expression in HCT-116 colorectal carcinoma cells was performed to determine the potential of TRIP-Br2 as a novel chemotherapeutic drug target. Results Overexpression of TRIP-Br2 is sufficient to transform murine fibroblasts and promotes tumorigenesis in nude mice. The transformed phenotype is characterized by deregulation of the E2F/DP-transcriptional pathway through upregulation of the key E2F-responsive genes CYCLIN E, CYCLIN A2, CDC6 and DHFR. TRIP-Br2 is frequently overexpressed in both cancer cell lines and multiple human tumors. Clinicopathologic correlation indicates that overexpression of TRIP-Br2 in hepatocellular carcinoma is associated with a worse clinical outcome by Kaplan-Meier survival analysis. Small interfering RNA-mediated (siRNA knockdown of TRIP-Br2 was sufficient to inhibit cell-autonomous growth of HCT-116 cells in vitro. Conclusion This study identifies TRIP-Br2 as a bona-fide protooncogene and supports the potential for TRIP-Br2 as a novel prognostic marker and a chemotherapeutic drug target in human cancer.

  11. Small break LOCA analysis for RCP trip strategy for YGN 3 and 4 emergency procedure guidelines

    International Nuclear Information System (INIS)

    Suh, Jong Tae; Bae, Kyoo Hwan

    1995-01-01

    A continued operation of RCPs during a certain small break LOCA may increase unnecessary inventory loss from the RCS causing a severe core uncovery which might lead to a fuel failure. After TMI-2 accident, the CEOG developed RCP trip strategy called 'Trip-Two/Leave-Two' (T2/L2) in response to NRC requests and incorporated it in the generic EPG for CE plants. The T2/L2 RCP trip strategy consists of tripping the first two RCPs on low RCS pressure and then tripping the remaining two RCPs if a LOCA has occurred. This analysis determines the RCP trip setpoint and demonstrates the safe operational aspects of RCP trip strategy during a small break LOCA for YGN 3 and 4. The trip setpoint of the first two RCPs for YGN 3 and 4 is calculated to be 1775 psia in pressurizer pressure based on the limiting small break LOCA with 0.15 ft 2 break size in the hot leg. The analysis results show that YGN 3 and 4 can maintain the core coolability even if the operator fails to trip the second two RCPs or trips at worst time. Also, the YGN 3 and 4 RCP trip strategy demonstrates that both the 10 CFR 50.46 requirements on PCT and the ANSI standards 58.8 requirements on operator action time can be satisfied with enough margin. Therefore, it is concluded that the T2/L2 RCP trip strategy with a trip setpoint of 1775 psia for YGN 3 and 4 can provide improved operator guidance for the RCP operation during accidents. 11 figs., 4 tabs., 9 refs. (Author)

  12. Influence of Field Trip on the Development of Students Interest ...

    African Journals Online (AJOL)

    Result of the study showed that; field trip increased students' interest towards studying fine and applied art theory and practicals. Male interest towards studying fine and applied art after embarking on field trip is slightly higher than their female counterpart but the difference is not significant at 0.05 alpha level under 56 ...

  13. Nuevos atrayentes de trips ayudan a los agricultores en el control de plagas

    NARCIS (Netherlands)

    Tol, van R.W.H.M.; Kogel, de W.J.; Teulon, D.

    2007-01-01

    Los trips constituyen una plaga importante que afecta a muchos cultivos diferentes. El año pasado se probaron con éxito, en situaciones prácticas, aromas atrayentes de trips de las flores y trips de la cebolla. El producto, que estará a disposición de los cultivadores en junio, resultó efectivo en

  14. Post-arc current simulation based on measurement in vacuum circuit breaker with a one-dimensional particle-in-cell model

    Science.gov (United States)

    Jia, Shenli; Mo, Yongpeng; Shi, Zongqian; Li, Junliang; Wang, Lijun

    2017-10-01

    The post-arc dielectric recovery process has a decisive effect on the current interruption performance in a vacuum circuit breaker. The dissipation of residual plasma at the moment of current zero under the transient recovery voltage, which is the first stage of the post-arc dielectric recovery process and forms the post-arc current, has attracted many concerns. A one-dimensional particle-in-cell model is developed to simulate the measured post-arc current in the vacuum circuit breaker in this paper. At first, the parameters of the residual plasma are estimated roughly by the waveform of the post-arc current which is taken from measurements. After that, different components of the post-arc current, which are formed by the movement of charged particles in the residual plasma, are discussed. Then, the residual plasma density is adjusted according to the proportion of electrons and ions absorbed by the post-arc anode derived from the particle-in-cell simulation. After this adjustment, the post-arc current waveform obtained from the simulation is closer to that obtained from measurements.

  15. Current identification in vacuum circuit breakers as a least squares problem*

    Directory of Open Access Journals (Sweden)

    Ghezzi Luca

    2013-01-01

    Full Text Available In this work, a magnetostatic inverse problem is solved, in order to reconstruct the electric current distribution inside high voltage, vacuum circuit breakers from measurements of the outside magnetic field. The (rectangular final algebraic linear system is solved in the least square sense, by involving a regularized singular value decomposition of the system matrix. An approximated distribution of the electric current is thus returned, without the theoretical problem which is encountered with optical methods of matching light to temperature and finally to current density. The feasibility is justified from the computational point of view as the (industrial goal is to evaluate whether, or to what extent in terms of accuracy, a given experimental set-up (number and noise level of sensors is adequate to work as a “magnetic camera” for a given circuit breaker. Dans cet article, on résout un problème inverse magnétostatique pour déterminer la distribution du courant électrique dans le vide d’un disjoncteur à haute tension à partir des mesures du champ magnétique extérieur. Le système algébrique (rectangulaire final est résolu au sens des moindres carrés en faisant appel à une décomposition en valeurs singulières regularisée de la matrice du système. On obtient ainsi une approximation de la distribution du courant électrique sans le problème théorique propre des méthodes optiques qui est celui de relier la lumière à la température et donc à la densité du courant. La faisabilité est justifiée d’un point de vue numérique car le but (industriel est d’évaluer si, ou à quelle précision, un dispositif expérimental donné (nombre et seuil limite de bruit des senseurs peut travailler comme une “caméra magnétique” pour un certain disjoncteur.

  16. The SMS-GPS-Trip-Method

    DEFF Research Database (Denmark)

    Reinau, Kristian Hegner; Harder, Henrik; Weber, Michael

    2015-01-01

    This article presents a new method for collecting travel behavior data, based on a combination of GPS tracking and SMS technology, coined the SMS–GPS-Trip method. The state-of-the-art method for collecting data for activity based traffic models is a combination of travel diaries and GPS tracking...

  17. Assessment of vehicle trip production rates in Ilorin (Nigeria) | Jimoh ...

    African Journals Online (AJOL)

    Occupation, age, gender, income lev-el, vehicle ownership, trip length and fare structure affected the total trip generation, with an average production rate of 3.5, in the range of 2.79 - 4.29. The lower rate was characteristic of school children (5 - 15 years), while the highest rate was attributed to affluent and elderly persons ...

  18. Large Pelagic Logbook Trip Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch and effort for fishing trips that are taken by vessels with a Federal permit issued for the swordfish and sharks under the Highly...

  19. An Evaluation of Telecommuting As a Trip Reduction Measure

    OpenAIRE

    Kitamura, Ryuichi; Mokhtarian, Patricia L.; Pendyala, Ram M.

    1991-01-01

    Telecommuting, which is the performance of work at home or at a center close to home using telecommunications, has attracted growing interest among planners and researchers as a strategy for reducing traveldemand. This paper investigates the potential of telecommuting as a trip reduction measure, using data obtained from a telecommuting pilot project involving State of California government employees. In this pilot project, a three-day trip diary was administered, before and after te...

  20. On the upper ocean turbulent dissipation rate due to microscale breakers and small whitecaps

    Science.gov (United States)

    Banner, Michael L.; Morison, Russel P.

    2018-06-01

    In ocean wave modelling, accurately computing the evolution of the wind-wave spectrum depends on the source terms and the spectral bandwidth used. The wave dissipation rate source term which spectrally quantifies wave breaking and other dissipative processes remains poorly understood, including the spectral bandwidth needed to capture the essential model physics. The observational study of Sutherland and Melville (2015a) investigated the relative dissipation rate contributions of breaking waves, from large-scale whitecaps to microbreakers. They concluded that a large fraction of wave energy was dissipated by microbreakers. However, in strong contrast with their findings, our analysis of their data and other recent data sets shows that for young seas, microbreakers and small whitecaps contribute only a small fraction of the total breaking wave dissipation rate. For older seas, we find microbreakers and small whitecaps contribute a large fraction of the breaking wave dissipation rate, but this is only a small fraction of the total dissipation rate, which is now dominated by non-breaking contributions. Hence, for all the wave age conditions observed, microbreakers make an insignificant contribution to the total wave dissipation rate in the wave boundary layer. We tested the sensitivity of the results to the SM15a whitecap analysis methodology by transforming the SM15a breaking data using our breaking crest processing methodology. This resulted in the small-scale breaking waves making an even smaller contribution to the total wave dissipation rate, and so the result is independent of the breaker processing methodology. Comparison with other near-surface total TKE dissipation rate observations also support this conclusion. These contributions to the spectral dissipation rate in ocean wave models are small and need not be explicitly resolved.

  1. Student Self-Reported Learning Outcomes of Field Trips: The pedagogical impact

    Science.gov (United States)

    Lavie Alon, Nirit; Tal, Tali

    2015-05-01

    In this study, we used the classification and regression trees (CART) method to draw relationships between student self-reported learning outcomes in 26 field trips to natural environments and various characteristics of the field trip that include variables associated with preparation and pedagogy. We wished to examine the extent to which the preparation for the field trip, its connection to the school curriculum, and the pedagogies used, affect students' self-reported outcomes in three domains: cognitive, affective, and behavioral; and the extent the students' socioeconomic group and the guide's affiliation affect students' reported learning outcomes. Given that most of the field trips were guide-centered, the most important variable that affected the three domains of outcomes was the guide's storytelling. Other variables that showed relationships with self-reported outcomes were physical activity and making connections to everyday life-all of which we defined as pedagogical variables. We found no significant differences in student self-reported outcomes with respect to their socioeconomic group and the guide's organizational affiliation.

  2. Mode, load, and specific climate impact from passenger trips.

    Science.gov (United States)

    Borken-Kleefeld, Jens; Fuglestvedt, Jan; Berntsen, Terje

    2013-07-16

    The climate impact from a long-distance trip can easily vary by a factor of 10 per passenger depending on mode choice, vehicle efficiency, and occupancy. In this paper we compare the specific climate impact of long-distance car travel with coach, train, or air trips. We account for both, CO2 emissions and short-lived climate forcers. This particularly affects the ranking of aircraft's climate impact relative to other modes. We calculate the specific impact for the Global Warming Potential and the Global Temperature Change Potential, considering time horizons between 20 and 100 years, and compare with results accounting only for CO2 emissions. The car's fuel efficiency and occupancy are central whether the impact from a trip is as high as from air travel or as low as from train travel. These results can be used for carbon-offsetting schemes, mode choice and transportation planning for climate mitigation.

  3. Are short daily trips compensated by higher leisure mobility?

    DEFF Research Database (Denmark)

    Næss, Petter

    2006-01-01

    Studies in several cities have shown that inner-city residents travel shorter distances and use cars less for local transport than suburbanites do. However, according to some authors, a low daily amount of travel is likely to be compensated through more extensive leisure mobility at weekends...... and on holidays. On the basis of a study of residential location and travel in the Copenhagen metropolitan area, this paper addresses the phenomenon of compensatory travel. For travel within ‘weekend trip distance’ from the residence, inner-city living appears to have a certain compensatory effect in the form...... of a higher frequency of medium-distance leisure trips. Probably, this reflects a shortage of nature in the immediate surroundings of the dwelling as well as less leisure time tied to gardening and house maintenance. These compensatory trips imply a slight reduction of the transport-reducing effect of inner...

  4. Impacts of energy consumption and emissions on the trip cost without late arrival at the equilibrium state

    Science.gov (United States)

    Tang, Tie-Qiao; Wang, Tao; Chen, Liang; Shang, Hua-Yan

    2017-08-01

    In this paper, we apply a car-following model, fuel consumption model, emission model and electricity consumption model to explore the influences of energy consumption and emissions on each commuter's trip costs without late arrival at the equilibrium state. The numerical results show that the energy consumption and emissions have significant impacts on each commuter's trip cost without late arrival at the equilibrium state. The fuel cost and emission cost prominently enhance each commuter's trip cost and the trip cost increases with the number of vehicles, which shows that considering the fuel cost and emission cost in the trip cost will destroy the equilibrium state. However, the electricity cost slightly enhances each commuter's trip cost, but the trip cost is still approximately a constant, which indicates that considering the electricity cost in the trip cost does not destroy the equilibrium state.

  5. THE NETWORK OF CITY PUBLIC TRANSPORT AS THE BASE FOR TRIP LENGTH DISTRIBUTION DETERMINING

    Directory of Open Access Journals (Sweden)

    P. Horbachov

    2015-07-01

    Full Text Available The up-to-date methods of modelling the demand for public transport services require an objective estimation and improvement. Such an improvement can be achieved by taking into account the trip length distribution during trip matrix calculation that requires determining the reasons of regularities occurance in city population trip lengths.

  6. Password Based Distribution Panel and Circuit Breaker Operation for the Safety of Lineman during Maintenance Work

    OpenAIRE

    Hudedmani, Mallikarjun G; Ummannanavar, Nitin; Mudaliar, Mani Dheeraj; Sooji, Chandana; Bogar, Mala

    2017-01-01

    Security is the prime concern in our day to day life while performing any activity. In the current scenario, accidental death of lineman is often read and evidenced. In this direction, a safety measure to safe guard the operator is found very necessary looking into the present working style. The electric lineman safety system is designed to control the control panel doors and circuit breaker by using a password for the safety. Critical electrical accidents to lineman are on the rise during el...

  7. Trip Travel Time Forecasting Based on Selective Forgetting Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Zhiming Gui

    2014-01-01

    Full Text Available Travel time estimation on road networks is a valuable traffic metric. In this paper, we propose a machine learning based method for trip travel time estimation in road networks. The method uses the historical trip information extracted from taxis trace data as the training data. An optimized online sequential extreme machine, selective forgetting extreme learning machine, is adopted to make the prediction. Its selective forgetting learning ability enables the prediction algorithm to adapt to trip conditions changes well. Experimental results using real-life taxis trace data show that the forecasting model provides an effective and practical way for the travel time forecasting.

  8. Small break LOCA analysis for YGN 5 and 6 RCP trip strategy in power mode operation

    International Nuclear Information System (INIS)

    Kim, Tech Mo; Choi, Han Rim

    2001-01-01

    A continued operation of Reactor Coolant Pumps(RCPs) during a Small Break Loss of Coolant Accident(SBLOCA) in all operation mode may increase unnecessary inventory loss from the Reactor Coolant System(RCS) causing a severe core uncovery which might lead to fuel failure. After Three Mile Island Unit 2(TMI-2) accident, the Combustion Engineering Owner Group(CEOG) developed RCP trip strategy called 'Trip-Two/Leave-Two' (T2/L2). The T2/L2 RCP trip strategy consists of tripping the first two RCPs on low RCS pressure and then tripping the remaining two RCPs if a LOCA has occurred. This analysis demonstrates the inherent safety of RCP trip strategy during an SBLOCA for Youggwang Nuclear Power Plant Unit 5 and 6(YGN 5 and 6). The trip setpoint of the first two RCPs for YGN 5 and 6 is calculated to be 1721 psia in pressurizer pressure based on the limiting SBLOCA with 0.15 ft 2 break size in the hot leg. The analysis results show that YGN 5 and 6 can maintain the core coolability even if the operator fails to trip the second two RCPs or trips at the worst time of minimum liquid inventory

  9. AN INTEGRATED MODELING FRAMEWORK FOR ENVIRONMENTALLY EFFICIENT CAR OWNERSHIP AND TRIP BALANCE

    Directory of Open Access Journals (Sweden)

    Tao FENG

    2008-01-01

    Full Text Available Urban transport emissions generated by automobile trips are greatly responsible for atmospheric pollution in both developed and developing countries. To match the long-term target of sustainable development, it seems to be important to specify the feasible level of car ownership and travel demand from environmental considerations. This research intends to propose an integrated modeling framework for optimal construction of a comprehensive transportation system by taking into consideration environmental constraints. The modeling system is actually a combination of multiple essential models and illustrated by using a bi-level programming approach. In the upper level, the maximization of both total car ownership and total number of trips by private and public travel modes is set as the objective function and as the constraints, the total emission levels at all the zones are set to not exceed the relating environmental capacities. Maximizing the total trips by private and public travel modes allows policy makers to take into account trip balance to meet both the mobility levels required by travelers and the environmentally friendly transportation system goals. The lower level problem is a combined trip distribution and assignment model incorporating traveler's route choice behavior. A logit-type aggregate modal split model is established to connect the two level problems. In terms of the solution method for the integrated model, a genetic algorithm is applied. A case study is conducted using road network data and person-trip (PT data collected in Dalian city, China. The analysis results showed that the amount of environmentally efficient car ownership and number of trips by different travel modes could be obtained simultaneously when considering the zonal control of environmental capacity within the framework of the proposed integrated model. The observed car ownership in zones could be increased or decreased towards the macroscopic optimization

  10. Laboratory effectiveness testing of water-in-oil emulsion breakers

    International Nuclear Information System (INIS)

    Fingas, M.F.; Fieldhouse, B.; Bier, I.; Conrod, D.; Tennyson, E.

    1995-01-01

    The physics and chemistry of water-in-oil emulsions dominate the development of effectiveness tests. Emulsions are variable in stability--this variability is largely dependent on oil type and degree of weathering. These factors complicate the development of a test. Emulsions which have low stability will apparently break easily with chemical emulsion breakers. Broken emulsions will form a foam-like material, called rag, which retains water which is not part of the stable emulsions. Analytical methods used to determine the final stability of the broken or unbroken emulsion were evaluated. Measurements of water content and viscosity measurements show correlation to emulsion stability. Viscosity provides a more reliable measure of emulsion stability but water content measurements are more convenient and are largely used in this study. Twelve tests were developed in the past. Two testing methods have been developed to a usable stage. These tests are described and data using them provided. The effects of mixing time, agent amount, settling time and mixing energy on effectiveness results are presented

  11. Medical and pharmacy student concerns about participating on international service-learning trips.

    Science.gov (United States)

    Chuang, Chih; Khatri, Siddique H; Gill, Manpal S; Trehan, Naveen; Masineni, Silpa; Chikkam, Vineela; Farah, Guillaume G; Khan, Amber; Levine, Diane L

    2015-12-23

    International Service Learning Trips (ISLT) provide health professional students the opportunity to provide healthcare, under the direction of trained faculty, to underserved populations in developing countries. Despite recent increases in international service learning trips, there is scant literature addressing concerns students have prior to attending such trips. This study focuses on identifying concerns before and after attending an ISLT and their impact on students. A survey comprised of closed and open-ended questions was developed to elucidate student concerns prior to attending an ISLT and experiences which might influence concerns. A five-point Likert-scale (extremely concerned = 1, minimally concerned = 5) was used to rate apprehension and satisfaction. Paired t-test was used to compare pre- and post-trip concerns; Chi-Square test was used to compare groups. Thirty-five students (27 medical, 8 pharmacy) attended ISLTs in December 2013. All completed pre and post-trip surveys. Significant decreases were seen in concerns related to cultural barriers (4.14 vs 4.46, P = .047), disease/epidemics (3.34 vs 4.60, P travel (3.86 vs 4.51, P food (3.83 vs 4.60, P students described benefits of attending an ISLT. Students had multiple concerns prior to attending an ISLT. Most decreased upon return. Addressing concerns has the potential to decrease student apprehension. The results of this study highlight the benefits of providing ISLTs and supporting development of a curriculum incorporating trip-related concerns.

  12. Performance evaluation of accelerated protection for microgrids

    Energy Technology Data Exchange (ETDEWEB)

    Wei, P.; Lin, X. [Huazhong Univ. of Science and Technology (China); Klimek, A. [Powertech Labs Inc., Surrey, BC (Canada); Bo, Z. [Alstom Grid Automation (United Kingdom)

    2010-07-01

    The constraints of existing power system facilities are becoming apparent as the demand for electricity increases. This paper discussed the use of microgrids as a means of improving power quality, safety, and stability. There are currently 2 main methods for protecting microgrids, notably voltage measurement, and a differential current method. The methods both assume that the microgrid is divided into zones determined by the location of distributed generators (DGs) in the power system. When faults are detected by protection relays, the DG in the microgrid zone will be shut off. Conventional protection coordination methods result in long fault clearance times. Relay coordination calculation methods are complicated when microgrids include a number of DGs that may be vulnerable to fault disturbances. This paper described a non-communication protection technique designed to detect faults zones using a superimposed phase current of the sound phase following breaker trips at the other end of the faulted line section. The method was designed to accelerate the tripping speed of the breaker at the local end of the faulted line. The technique can also be used to protect distribution systems with double source or radial configurations. 5 refs., 2 tabs., 14 figs.

  13. The Impact Of Surface Shape Of Chip-Breaker On Machined Surface

    Science.gov (United States)

    Šajgalík, Michal; Czán, Andrej; Martinček, Juraj; Varga, Daniel; Hemžský, Pavel; Pitela, David

    2015-12-01

    Machined surface is one of the most used indicators of workpiece quality. But machined surface is influenced by several factors such as cutting parameters, cutting material, shape of cutting tool or cutting insert, micro-structure of machined material and other known as technological parameters. By improving of these parameters, we can improve machined surface. In the machining, there is important to identify the characteristics of main product of these processes - workpiece, but also the byproduct - the chip. Size and shape of chip has impact on lifetime of cutting tools and its inappropriate form can influence the machine functionality and lifetime, too. This article deals with elimination of long chip created when machining of shaft in automotive industry and with impact of shape of chip-breaker on shape of chip in various cutting conditions based on production requirements.

  14. How Do We Resolve Holiday Problems?

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Chinese Ministry of Railways statistics show that from September 28 to October 7,the National Day Holiday period,China’s railway networks were used for 67 million trips,an all-time high.On October 1 alone,8.9 million trips

  15. A Quasi-Practical Interstellar Rocket Trip

    Science.gov (United States)

    Edmonds, James D., Jr.

    1974-01-01

    Mathematically shows that in principle a spaceship could travel eight light years in ten earth years, with the passengers arriving 4.6 years older than when they left earth and having experienced an acceleration induced effective gravity of one g for the entire trip. (MLH)

  16. An integrative conceptual framework for analyzing customer satisfaction with shopping trip experiences in grocery retailing

    DEFF Research Database (Denmark)

    Esbjerg, Lars; Jensen, Birger Boutrup; Bech-Larsen, Tino

    2012-01-01

    Grocery retailers aim to satisfy customers, and because grocery shopping trips are frequently recurring, they must do socontinuously. Surprisingly, little research has addressed satisfaction with individual grocery shopping trips. This article therefore develops a conceptual framework for analyzing...... customer satisfaction with individual grocery shopping trip experiences within a overall ‘disconfirmation of expectations model’ of customer satisfaction. The contribution of the framework is twofold. First, by focusing on satisfaction with individual grocery shopping trips, previous research...... on satisfaction in the retailing literature. Second, the framework synthesizes and integrates multiple central concepts from different research streams into a common framework for analyzing shopping trip satisfaction. Propositions are derived regarding the relationships among the different concepts...

  17. The use of dendrimers as high-performance shells for round-trip energy transfer: efficient trans-cis photoisomerization from an excited triplet state produced within a dendrimer shell.

    Science.gov (United States)

    Miura, Yousuke; Momotake, Atsuya; Takeuchi, Keiichirou; Arai, Tatsuo

    2011-01-01

    A series of stilbene-cored poly(benzyl ether) dendrimers with benzophenone peripheries were synthesized and their photophysical and photochemical properties were studied. Fluorescence studies revealed that singlet-singlet energy transfer (SSET) from the stilbene core to the benzophenone units took place efficiently in dendrimers of all generations. Similarly, phosphorescence and time-resolved spectroscopic measurements indicated efficient triplet-triplet energy transfer (TTET) from the benzophenone periphery to the stilbene core. Upon excitation at 310 nm, the stilbene core isomerizes via an energy round trip within the dendrimer shell. The quantum yields for the energy round trip (Φ(ERT)), defined as the product of the quantum yields of SSET, intersystem crossing, and TTET (Φ(ERT) = Φ(SS)Φ(isc)Φ(TT)), were extremely high for all generations--99%, 95% and 94% for G1, G2, and G3, respectively--which means that the excitation energy of the dendrimer core was transferred to the dendrimer periphery and back to the core almost quantitatively. The quantum yield for photoisomerization of G1-G3 via an energy round trip was higher than for other stilbene-cored dendrimers, which mainly isomerize from the excited singlet state. Photostability in the dendrimers was also demonstrated and discussed.

  18. Round-trip boat on hydrogen

    International Nuclear Information System (INIS)

    Berends, A.M.; Van der Laag, P.C.

    2005-08-01

    The results of a feasibility study on a PEM (polymer-electrolyte membrane) fuel cell (FC) driven electric round-trip boat are presented and discussed. The study concerns the specification of a PEMFC system design, including a list of components. Also technical and environmental aspects are dealt with and compared with traditional battery-driven electric boats and diesel-driven boats [nl

  19. Accounting for Laminar Run & Trip Drag in Supersonic Cruise Performance Testing

    Science.gov (United States)

    Goodsell, Aga M.; Kennelly, Robert A.

    1999-01-01

    An improved laminar run and trip drag correction methodology for supersonic cruise performance testing was derived. This method required more careful analysis of the flow visualization images which revealed delayed transition particularly on the inboard upper surface, even for the largest trip disks. In addition, a new code was developed to estimate the laminar run correction. Once the data were corrected for laminar run, the correct approach to the analysis of the trip drag became evident. Although the data originally appeared confusing, the corrected data are consistent with previous results. Furthermore, the modified approach, which was described in this presentation, extends prior historical work by taking into account the delayed transition caused by the blunt leading edges.

  20. Scaled photographs of surf over the full range of breaker sizes on the north shore of Oahu and Jaws, Maui, Hawaiian Islands (NODC Accession 0001753)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digital surf photographs were scaled using surfers as height benchmarks to estimate the size of the breakers. Historical databases for surf height in Hawaii are...

  1. Personal and environmental characteristics associated with choice of active transport modes versus car use for different trip purposes of trips up to 7.5 kilometers in The Netherlands.

    Directory of Open Access Journals (Sweden)

    Eline Scheepers

    Full Text Available INTRODUCTION: This explorative study examines personal and neighbourhood characteristics associated with short-distance trips made by car, bicycle or walking in order to identify target groups for future interventions. METHODS: Data were derived from 'Mobility Research Netherlands (2004-2009; MON', a dataset including information regarding trips made by household members (n = ±53,000 respondents annually. Using postal codes of household addresses, MON data were enriched with data on neighbourhood typologies. Multilevel logistic modelling was used to calculate odds ratio (OR of active transport versus car use associated with four different trip purposes (shopping (reference, commuting, taking or bringing persons or sports. A total of 277,292 short distance trips made by 102,885 persons were included in analyses. RESULTS: Compared to women shopping, women less often take active transport to sports clubs (OR = 0.88 and men less often take active transport for shopping (OR = 0.92, or for bringing or taking persons (OR = 0.76. Those aged 25-34 years (OR = 0.83 and 35-44 years (OR = 0.96 were more likely to use active transport for taking or bringing persons than persons belonging to the other age groups (relative to trips made for shopping by those 65 years or over. A higher use of active transport modes by persons with an university or college degree was found and particularly persons living in urban-centre neighbourhoods were likely to use active transport modes. CONCLUSION: IN DEVELOPING POLICIES PROMOTING A MODE SHIFT SPECIAL ATTENTION SHOULD BE GIVEN TO THE FOLLOWING GROUPS: a men making short distance trips for taking or bringing persons, b women making short distance trips to sport facilities, c persons belonging to the age groups of 25-44 years of age, d Persons with a primary school or lower general secondary education degree and persons with a high school or secondary school degree and e persons living in rural or

  2. The effect of an advanced glycation end-product crosslink breaker and exercise training on vascular function in older individuals: a randomized factorial design trial.

    NARCIS (Netherlands)

    Oudegeest-Sander, M.H.; Olde Rikkert, M.G.M.; Smits, P.; Thijssen, D.H.J.; Dijk, A.P.J. van; Levine, B.D.; Hopman, M.T.E.

    2013-01-01

    Aging leads to accumulation of irreversible advanced glycation end-products (AGEs), contributing to vascular stiffening and endothelial dysfunction. When combined with the AGE-crosslink breaker Alagebrium, exercise training reverses cardiovascular aging in experimental animals. This study is the

  3. Reprises textuelles dans The Dew Breaker d’Edwidge Danticat Rewriting / Reprising in Edwidge Danticat’s The Dew Breaker

    Directory of Open Access Journals (Sweden)

    Corinne Duboin

    2007-01-01

    Full Text Available In her recent novel, The Dew Breaker (2004, Haitian-American writer Edwidge Danticat weaves together the lives of her bruised Haitian characters and their torturer, a former Tonton Macoute, all in exile in the US. Seven of the nine chapters were previously published as separate short stories and have been rearranged to form a novel. The reader is then led to unravel a narrative tangle made of many threads. The disparate nature of the book, its non-linear narrative, the plurality of stories and voices, the gaps in a fragmented, elliptic text all bear witness to an alternative approach to creative writing. Like a seamstress, the novelist pieces together individual stories, connecting them as the multifarious facets of a great whole. In the wake of francophone Haitian writers (namely Jacques Roumain, the author of Masters of the Dew, and Jacques Stephen Alexis who wrote General Sun, My Brother, Edwidge Danticat fictionalizes the traumatic history of a people confronted with violence and terror and engages in a complex intertextual game. Combining ethics and aesthetics, temporal and textual memory, the novelist explores facts and, rather than giving answers, raises difficult questions. Her characters, whether victims or perpetrators, all strive to free themselves from a haunting past: is it ever possible to forgive so as to heal the pain? Can one make amends for the harm that has been done to victims who seek redress?

  4. A Land-use Approach for Capturing Future Trip Generating Poles

    Directory of Open Access Journals (Sweden)

    Iraklis Stamos

    2015-12-01

    Full Text Available Changes in the usage of a particular urban or regional area have immediate effects on transportation, such as the development of a new multimodal terminal within a city, or the creation of a business park in its outskirts. Thus far, this correlation has been under-researched at a national level in Greece. As a result, its effects on trip generation and passenger flows has been underestimated at the planning level, leading to the implementation of projects that are neither viable nor sustainable. This paper proposes that land use changes ought to be considered in tandem with transport-related changes at the planning stage. To this effect, we present a three-step methodology for an integrated approach to capturing future trip generation: the identification of future trip-generating poles within the study area; the development of scenarios related to the probability of these changes occurring and their potential magnitude; an estimation of future trends in passenger flows. The methodology is applied to the Metropolitan area of Thessaloniki, Greece. Using data obtained from development plans, national statistical services and research projects’ and studies’ findings, we estimate future trip-generation subsequent to land use change. Data is processed and evaluated by a local experts’ group, representing various key-disciplines of the area’s planning stakeholders.

  5. Anything Can Happen out There: A Holistic Approach to Field Trips

    Science.gov (United States)

    Plutino, Alessia

    2016-01-01

    This paper looks back at an academic-led language field trip project, now in its third year, involving ab-initio students of Italian at the University of Southampton. It considers the role of academic-led field trips in Modern Languages (ML) and it explores the underlying pedagogical approaches that were adopted to enhance students' engagement,…

  6. Flow protection trip limits operational charge-discharge facility -- C Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Van Wormer, F.W.

    1958-09-19

    Because of wide variations in the venturi throat pressure, well beyond the panellit gage trip range, that occur during the sequence of operational charge-discharge, the panellit gage cannot be included in the scram safety circuit during the period of time that charge- discharge operations are being performed. In its stead, the function of the panellit gage is replaced in an overlapping manner by a tube inlet pressure monitor that is equipped with high and low pressure trip mechanisms that may be included in the scram safety circuit during the time that the panellit gage must be by-passed. The tube inlet pressure monitor is then used to provide the protection from unstable flow that is normally obtained with the panellit gage. This memorandum describes the manner in which the tube inlet pressure monitor trip points are to be determined and used.

  7. IE Information Notice No. 85-18, Supplement 1: Failures of undervoltage output circuit boards in the Westinghouse-designed solid state protection system

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    The US Nuclear Regulatory Commission (NRC) is issuing this information notice supplement to alert addressees to continuing problems associated with the undervoltage (UV) output circuit boards (driver cards) in the solid state protection system (SSPS) designed by the Westinghouse Electric Corporation (Westinghouse). On June 3, 1991, the Shearon Harris Nuclear Power Plant, Unit 1, (Harris) experienced an automatic reactor trip from 100 percent power on a spurious low reactor coolant system loop flow signal. The signal was generated as a result of a surveillance test being performed on one of three loop flow transmitters. The licensee attributed the spurious signal to both procedural inadequacies and personnel error. A control room operator verified that all control rods had fully inserted following the trip signal and that reactor power was properly decreasing. However, about 22 seconds after the automatic trip signal was generated, operators discovered that the ''A'' reactor trip breaker (RTB) had not opened. The RTB was manually opened using the reactor trip switch on the main control board. Subsequent analyses are discussed

  8. Design and Optimization of an Austenitic TRIP Steel for Blast and Fragment Protection

    Science.gov (United States)

    Feinberg, Zechariah Daniel

    In light of the pervasive nature of terrorist attacks, there is a pressing need for the design and optimization of next generation materials for blast and fragment protection applications. Sadhukhan used computational tools and a systems-based approach to design TRIP-120---a fully austenitic transformation-induced plasticity (TRIP) steel. Current work more completely evaluates the mechanical properties of the prototype, optimizes the processing for high performance in tension and shear, and builds models for more predictive power of the mechanical behavior and austenite stability. Under quasi-static and dynamic tension and shear, the design exhibits high strength and high uniform ductility as a result of a strain hardening effect that arises with martensitic transformation. Significantly more martensitic transformation occurred under quasi-static loading conditions (69% in tension and 52% in shear) compared to dynamic loading conditions (13% tension and 5% in shear). Nonetheless, significant transformation occurs at high-strain rates which increases strain hardening, delays the onset of necking instability, and increases total energy absorption under adiabatic conditions. Although TRIP-120 effectively utilizes a TRIP effect to delay necking instability, a common trend of abrupt failure with limited fracture ductility was observed in tension and shear at all strain rates. Further characterization of the structure of TRIP-120 showed that an undesired grain boundary cellular reaction (η phase formation) consumed the fine dispersion of the metastable gamma' phase and limited the fracture ductility. A warm working procedure was added to the processing of TRIP-120 in order to eliminate the grain boundary cellular reaction from the structure. By eliminating η formation at the grain boundaries, warm-worked TRIP-120 exhibits a drastic improvement in the mechanical properties in tension and shear. In quasi-static tension, the optimized warm-worked TRIP-120 with an Mssigma

  9. Short-term service trips and the interprofessional team: a perspective from Honduras.

    Science.gov (United States)

    VanderWielen, Lynn M; Halder, Gabriela E; Enurah, Alexander S; Pearson, Catherine; Stevens, Michael P; Crossman, Steven H

    2015-03-01

    Short-term service trips from the USA annually spend over $250 million dollars to provide healthcare to individuals in developing nations. These trips often uniquely define goals as related to changes in the host population and overlook the valuable benefits potentially incurred by the trip volunteers. The Honduras Outreach Medical Brigada Relief Effort utilizes an interprofessional team approach to develop the dual goals of improving health and quality of life in host communities and improving interprofessional teamwork values and skills among participants. This article outlines details of this program, describes on-going evaluation work and discusses the interprofessional implications from this project.

  10. Trip-Induced Transition Measurements in a Hypersonic Boundary Layer Using Molecular Tagging Velocimetry

    Science.gov (United States)

    Bathel, Brett F.; Danehy, Paul M.; Jones, Stephen B.; Johansen, Craig T.; Goyne, Christopher P.

    2013-01-01

    Measurements of mean streamwise velocity, fluctuating streamwise velocity, and instantaneous streamwise velocity profiles in a hypersonic boundary layer were obtained over a 10-degree half-angle wedge model. A laser-induced fluorescence-based molecular tagging velocimetry technique was used to make the measurements. The nominal edge Mach number was 4.2. Velocity profiles were measured both in an untripped boundary layer and in the wake of a 4-mm diameter cylindrical tripping element centered 75.4 mm downstream of the sharp leading edge. Three different trip heights were investigated: k = 0.53 mm, k = 1.0 mm and k = 2.0 mm. The laminar boundary layer thickness at the position of the measurements was approximately 1 mm, though the exact thickness was dependent on Reynolds number and wall temperature. All of the measurements were made starting from a streamwise location approximately 18 mm downstream of the tripping element. This measurement region continued approximately 30 mm in the streamwise direction. Additionally, measurements were made at several spanwise locations. An analysis of flow features show how the magnitude, spatial location, and spatial growth of streamwise velocity instabilities are affected by parameters such as the ratio of trip height to boundary layer thickness and roughness Reynolds number. The fluctuating component of streamwise velocity measured along the centerline of the model increased from approximately 75 m/s with no trip to +/-225 m/s with a 0.53-mm trip, and to +/-240 m/s with a 1-mm trip, while holding the freestream Reynolds number constant. These measurements were performed in the 31-inch Mach 10 Air Tunnel at the NASA Langley Research Center.

  11. Real Students and Virtual Field Trips

    Science.gov (United States)

    de Paor, D. G.; Whitmeyer, S. J.; Bailey, J. E.; Schott, R. C.; Treves, R.; Scientific Team Of Www. Digitalplanet. Org

    2010-12-01

    Field trips have always been one of the major attractions of geoscience education, distinguishing courses in geology, geography, oceanography, etc., from laboratory-bound sciences such as nuclear physics or biochemistry. However, traditional field trips have been limited to regions with educationally useful exposures and to student populations with the necessary free time and financial resources. Two-year or commuter colleges serving worker-students cannot realistically insist on completion of field assignments and even well-endowed universities cannot take students to more than a handful of the best available field localities. Many instructors have attempted to bring the field into the classroom with the aid of technology. So-called Virtual Field Trips (VFTs) cannot replace the real experience for those that experience it but they are much better than nothing at all. We have been working to create transformative improvements in VFTs using four concepts: (i) self-drive virtual vehicles that students use to navigate the virtual globe under their own control; (ii) GigaPan outcrops that reveal successively more details views of key locations; (iii) virtual specimens scanned from real rocks, minerals, and fossils; and (iv) embedded assessment via logging of student actions. Students are represented by avatars of their own choosing and travel either together in a virtual field vehicle, or separately. When they approach virtual outcrops, virtual specimens become collectable and can be examined using Javascript controls that change magnification and orientation. These instructional resources are being made available via a new server under the domain name www.DigitalPlanet.org. The server will log student progress and provide immediate feedback. We aim to disseminate these resources widely and welcome feedback from instructors and students.

  12. The study on the threshold strain of microvoid formation in TRIP steels during tensile deformation

    International Nuclear Information System (INIS)

    Wang Wurong; Guo Bimeng; Ji Yurong; He Changwei; Wei Xicheng

    2012-01-01

    Highlights: ► The tensile mechanical behaviors of TRIP steels were studied under high rate deformation conditions. ► The threshold strain of microvoid formation was examined quantitatively. ► The effects of retained austenite of TRIP on suppressing microvoid formed during tensile process have been discussed. - Abstract: Transformation Induced Plasticity (TRIP) steels exhibit a better combination of strength and ductility properties than conventional high strength low alloy (HSLA) steels, and therefore receive considerable attention in the automotive industry. In this work, the tensile mechanical behaviors of TRIP-aided steels were studied under the condition of the quasi-static and high deformed rates. The deformed specimens were observed by scanning electron microscope (SEM) along the tensile axis. The threshold strain of microvoid formation was examined quantitatively according to the evolution of deformation. The results showed that: the yield and tensile strengths of TRIP steels increase with the strain rate, whereas their elongations decrease. However, the threshold strain for TRIP steels at high strain rate is larger than that at low strain rate. Comparing with the deformed microstructure and microvoids formed in the necking zone of dual phase (DP) steel, the progressive deformation-induced transformation of retained austenite in TRIP steels remarkably increases the threshold strain of microvoid formation and furthermore postpones its growth and coalescence.

  13. CNMI, American Samoa, and Guam Small Boat Fishery Trip Expenditure (2009 to present)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a time-series dataset of trip expenditure data including actual fishing trip expenses, input usage, and input prices, for boat-based reef fish, bottomfish,...

  14. THE TRIPS AGREEMENT, INTERNATIONAL TECHNOLOGY TRANSFER AND DEVELOPMENT: SOME LESSONS FROM STRENGTHENING IPR PROTECTION

    Directory of Open Access Journals (Sweden)

    M. Shugurov

    2016-01-01

    Full Text Available The article focuses on the impact of the TRIPS Agreement provisions on further development of international technology transfer (ITT mainly to developing countries. The authors review the critical specificity of ITT connected with the adoption of TRIPS. Much attention is paid to an analysis of what is most discussed among international experts in the area of the issues on the dual results of stronger intellectual property rights (IPRs concerning various groups of developing countries. Their study also examines a number of problems with implementation of the TRIPS provisions, conducive to ITT, in the context of the TRIPS-plus era as a new stage in strengthening IPR protection. Bearing in mind the fragmentation of the international regime of IPR protection because of the adoption of numerous regional free trade agreements, the authors outline the possible position of advanced developing and least developed countries with respect to using TRIPS potentials for development of ITT under reasonable and just terms, with the aim of overall prosperity.

  15. Trip generation data collection in urban areas.

    Science.gov (United States)

    2014-09-01

    There is currently limited data on urban, multimodal trip generation at the individual site level. This lack of : data limits the ability of transportation agencies to assess development impacts on the transportation system : in urban and multimodal ...

  16. Pedagogical Souvenirs: An Art Educator's Reflections on Field Trips as Professional Development

    Science.gov (United States)

    Kushins, Jodi

    2015-01-01

    This essay explores the nature and importance of field trips as sites for artistic development, intellectual fulfillment, and pedagogical inspiration. The author weaves personal reflections from a professional field trip and experience teaching art education online with creative and pedagogical references to make a case for experiential learning…

  17. Computer analysis on ANO-2 turbine trip test

    International Nuclear Information System (INIS)

    Senda, Yasuhide; Kanda, Keiji; McDonald, T.A.; Tessier, J.H.; Abramson, P.B.

    1983-01-01

    Safety analysis for nuclear power plants usually uses so detailed and large codes that it can be expensive and time-consuming. It is preferable to employ a simplified plant model to save cost and time. In this research, using RELAP5, a turbine trip test performed at Arkansas Nuclear One-Unit 2 (ANO-2) was analyzed with the simplified plant model in order to evaluate it for the turbine trip. Before the closure of the Main Steam Isolation Valve (MSIV), the calculation results agree well with the experimental data. After the MSIV closure, the results of the calculation explain the experimental data fairly well except for pressure recovery in the pressurizer. (author)

  18. Passive control of cavitating flow around an axisymmetric projectile by using a trip bar

    Directory of Open Access Journals (Sweden)

    Jian Huang

    2017-07-01

    Full Text Available Quasi-periodical evolutions such as shedding and collapsing of unsteady cloud cavitating flow, induce strong pressure fluctuations, what may deteriorate maneuvering stability and corrode surfaces of underwater vehicles. This paper analyzed effects on cavitation stability of a trip bar arranged on high-speed underwater projectile. Small scale water tank experiment and large eddy simulation using the open source software OpenFOAM were used, and the results agree well with each other. Results also indicate that trip bar can obstruct downstream re-entrant jet and pressure wave propagation caused by collapse, resulting in a relatively stable sheet cavity between trip bar and shoulder of projectiles. Keywords: Unsteady cavitating flow, Trip bar, Re-entrant jet, Passive flow control

  19. Factors affecting trip generation of motorcyclist for the purpose of non-mandatory activities

    Science.gov (United States)

    Anggraini, Renni; Sugiarto, Sugiarto; Pramanda, Heru

    2017-11-01

    The inadequate facilities and limited access to public transport reflect many people using private vehicles, in particular, motorcycle. The motorcycle is most widely used in Indonesia, recently, including Aceh Province. As a result, the number of motorcycle ownership is increasing significantly. The increasing number of motorcycles leads to complex traffic problems. Several factors tend to affect the trip generation of the motorcyclist, i.e., the social demographics of individuals and families, accessibility, etc. This study aims to analyze the characteristics of motorcyclists for non-mandatory activities, i.e. activities other than to work and school. It also aims to determine the dominant factors that affect their trips through trip generation models. The required data consist of primary data and secondary data. Primary data consists of a home interview survey that collects individual's daily trips. It is conducted by distributing the questionnaires to 400 families residing in Lhokseumawe City. Modeling the trip generation of the motorcyclist is done by multiple linear regression analysis. Parameters calibration uses OLS (Ordinary Least Square) method. The results showed that the dominant variables that affect the trip generation of motorcyclist for non-mandatory activities are license ownership, housewife, school-age children, middle-income household, and lower education level. It can be concluded that some factors affecting trip generation to non-work activities were female motorcyclists from the middle-income household with lower education level. As their status is mostly as the housewife, escorting children to non-school activities seems to the mother's task, instead of the father. It is clear that, most female ride motorcycle for doing household tasks. However, it should be noted that the use of the motorcycle in long-term does not suit for sustainable transportation.

  20. Survey on how fluctuating petrol prices are affecting Malaysian large city dwellers in changing their trip patterns

    Science.gov (United States)

    Rohani, M. M.; Pahazri, N.

    2018-04-01

    Rising fuel prices shocks have a significant impact on the way of life of most Malaysians. Due to the rising of oil prices, the costs of travel for private vehicle users are therefore increasing. The study was conducted based on the objective of studying the impact of rising fuel prices on three types of trip patterns of Malaysians who are living in the city areas. The three types of trip patterns are, workplaces trip, leisure trip and personal purposes trip during the weekdays. This study was conducted by distributing questionnaires to respondents of private vehicle users in selected city such as Johor Bahru, Kuala Lumpur, Putrajaya, Melaka, Perak, Selangor and Kelantan. This study, found that the trip patterns of those who were using their own vehicles had changed after the rising of fuel prices. The changes showed that many private vehicle users were taking steps to save money on petrol by adjusting their trips.

  1. The influence of TripAdvisor portal on hotel bussines in Serbia

    Directory of Open Access Journals (Sweden)

    Čačić Krunoslav

    2013-01-01

    Full Text Available Numerous researches have shown the existence of influence of specialized Web 2.0 portals on hotel business. One of most famous portals of that kind is TripAdvisor. The goal of this work is to determine the degree and mode of representation of hotels in Serbia on TripAdvisor portal. The results of the conducted research show that in past years the number of hotels from Serbia represented on this portal has increased significantly. At the end of 2012 there have been registered 3.288 comments which evaluated the service quality of 165 hotels from Serbia. The average vote, on five-degree scale, calculated at the level of all represented hotels at the end of 2012 was 3,92. Considering that Belgrade represents the primarily business, administrative and touristic center of Serbia, on the Belgrade's hotels specimen there has been analyzed the connection between business performances of hotels expressed through indicator TREVPAR and their image on TripAdvisor expressed through average vote determined based on user's comments, as well as in relation with TripAdvisor Popularity Index (TPI. The results show the high degree of correlation between analyzed features on the specimen of Belgrade's hotels, in range of hotels of second (4* and third category (3*. Having in mind the results of conducted research it is obvious that the hotels managers from Serbia should adopt and implement the corresponding procedures of monitoring and adequate reactions on contents on TripAdvisor, considering their influence on behavior of modern consumer in hotels.

  2. The Educational Value of Field Trips

    Science.gov (United States)

    Greene, Jay P.; Kisida, Brian; Bowen, Daniel H.

    2014-01-01

    The school field trip has a long history in American public education. For decades, students have piled into yellow buses to visit a variety of cultural institutions, including art, natural history, and science museums, as well as theaters, zoos, and historical sites. Schools gladly endured the expense and disruption of providing field trips…

  3. Forest Field Trips among High School Science Teachers in the Southern Piedmont

    Science.gov (United States)

    McCabe, Shannon M.; Munsell, John F.; Seiler, John R.

    2014-01-01

    Students benefit in many ways by taking field trips to forests. Improved academic performance, increased participation in outdoor recreation, and a better grasp of natural resources management are some of the advantages. However, trips are not easy for teachers to organize and lead. Declining budgets, on-campus schedules, and standards of learning…

  4. Microstructural Development during Welding of TRIP steels

    NARCIS (Netherlands)

    Amirthalingam, M.

    2010-01-01

    The Advanced High Strength Steels (AHSS) are promising solutions for the production of lighter automobiles which reduce fuel consumption and increase passenger safety by improving crash-worthiness. Transformation Induced Plasticity Steel (TRIP) are part of the advanced high strength steels which

  5. Technical evaluation of the proposed deletion of a reactor trip on a turbine trip below 50-percent power for the Beaver Valley nuclear power plant, Unit 1

    International Nuclear Information System (INIS)

    Reeves, W.E.

    1979-12-01

    This report documents the technical evaluation of the Duquesne Light Company's proposed license amendment for the deletion of a reactor trip on a turbine trip below 50% power for the Beaver Valley nuclear power plant, Unit 1. This report is supplied as part of the Selected Electrical, Instrumentation, and Control Systems Issues Program being conducted for the US Nuclear Regulatory Commission by Lawrence Livermore Laboratory

  6. Texture developed during deformation of Transformation Induced Plasticity (TRIP) steels

    International Nuclear Information System (INIS)

    Bhargava, M; Asim, T; Sushil, M; Shanta, C

    2015-01-01

    Automotive industry is currently focusing on using advanced high strength steels (AHSS) due to its high strength and formability for closure applications. Transformation Induced Plasticity (TRIP) steel is promising material for this application among other AHSS. The present work is focused on the microstructure development during deformation of TRIP steel sheets. To mimic complex strain path condition during forming of automotive body, Limit Dome Height (LDH) tests were conducted and samples were deformed in servo hydraulic press to find the different strain path. FEM Simulations were done to predict different strain path diagrams and compared with experimental results. There is a significant difference between experimental and simulation results as the existing material models are not applicable for TRIP steels. Micro texture studies were performed on the samples using EBSD and X-RD techniques. It was observed that austenite is transformed to martensite and texture developed during deformation had strong impact on limit strain and strain path. (paper)

  7. Texture developed during deformation of Transformation Induced Plasticity (TRIP) steels

    Science.gov (United States)

    Bhargava, M.; Shanta, C.; Asim, T.; Sushil, M.

    2015-04-01

    Automotive industry is currently focusing on using advanced high strength steels (AHSS) due to its high strength and formability for closure applications. Transformation Induced Plasticity (TRIP) steel is promising material for this application among other AHSS. The present work is focused on the microstructure development during deformation of TRIP steel sheets. To mimic complex strain path condition during forming of automotive body, Limit Dome Height (LDH) tests were conducted and samples were deformed in servo hydraulic press to find the different strain path. FEM Simulations were done to predict different strain path diagrams and compared with experimental results. There is a significant difference between experimental and simulation results as the existing material models are not applicable for TRIP steels. Micro texture studies were performed on the samples using EBSD and X-RD techniques. It was observed that austenite is transformed to martensite and texture developed during deformation had strong impact on limit strain and strain path.

  8. Improved trip generation data for Texas using workplace and special generator surveys : workshop materials.

    Science.gov (United States)

    2014-08-01

    Workshop Objectives: : Present Texas Trip Generation Manual : How developed : How it can be used, built upon : Provide examples and discuss : Present Generic WP Attraction Rates : Review Trip Attractions and Advanced Models

  9. PyTRiP - a toolbox and GUI for the proton/ion therapy planning system TRiP

    International Nuclear Information System (INIS)

    Toftegaard, J; Bassler, N; Petersen, J B

    2014-01-01

    Purpose: Only very few treatment planning systems (TPS) are capable of handling heavy ions. Commercial heavy ion TPS are costly and normally restrict the possibility to implement new functionalities. PyTRiP provides Python bindings and a platform-independent graphical user interface (GUI) for the heavy ion treatment program TRiP, and adds seamless support of DICOM files. We aim to provide a front-end for TRiP which does not require any special computer skills. Methods: PyTRiP is written in Python combined with C for fast computing. Routines for DICOM file import/export to TRiPs native file format are implemented. The GUI comes as an executable with all its dependencies including PyTRiP making it easy to install on Windows, Mac and Linux. Results: PyTRiP is a comprehensive toolbox for handling TRiP. Treatment plans are handled using an object oriented structure. Bindings to TRiP (which only runs on Linux, either locally or on a remote server) are performed through a single function call. GUI users can intuitively create treatment plans without much knowledge about the TRiP user interface. Advanced users still have full access to all TRiP functionality. The user interface comes with a comprehensive plotting tool, which can visualize 2D contours, volume histograms, as well as dose- and linear energy transfer (LET) distributions. Conclusion: We developed a powerful toolbox for ion therapy research using TRiP as backend. The corresponding GUI allows to easily and intuitively create, calculate and visualize treatment plans. TRiP is thereby more accessible and simpler to use.

  10. Using OpenTripPlanner to determine lowest cost home-work-home trips as an input to UrbanSim

    CSIR Research Space (South Africa)

    Waldeck, L

    2014-09-01

    Full Text Available for the provision of infrastructure and social facilities. The model is currently based on two open source projects, UrbanSim and Open Trip Planner. The paper describes the modifications that had to be introduced to apply the software in the South African context...

  11. TRIP13 is a protein-remodeling AAA+ ATPase that catalyzes MAD2 conformation switching.

    Science.gov (United States)

    Ye, Qiaozhen; Rosenberg, Scott C; Moeller, Arne; Speir, Jeffrey A; Su, Tiffany Y; Corbett, Kevin D

    2015-04-28

    The AAA+ family ATPase TRIP13 is a key regulator of meiotic recombination and the spindle assembly checkpoint, acting on signaling proteins of the conserved HORMA domain family. Here we present the structure of the Caenorhabditis elegans TRIP13 ortholog PCH-2, revealing a new family of AAA+ ATPase protein remodelers. PCH-2 possesses a substrate-recognition domain related to those of the protein remodelers NSF and p97, while its overall hexameric architecture and likely structural mechanism bear close similarities to the bacterial protein unfoldase ClpX. We find that TRIP13, aided by the adapter protein p31(comet), converts the HORMA-family spindle checkpoint protein MAD2 from a signaling-active 'closed' conformer to an inactive 'open' conformer. We propose that TRIP13 and p31(comet) collaborate to inactivate the spindle assembly checkpoint through MAD2 conformational conversion and disassembly of mitotic checkpoint complexes. A parallel HORMA protein disassembly activity likely underlies TRIP13's critical regulatory functions in meiotic chromosome structure and recombination.

  12. TRIP13 is a protein-remodeling AAA+ ATPase that catalyzes MAD2 conformation switching

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Qiaozhen [Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, United States; Rosenberg, Scott C. [Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, United States; Moeller, Arne [National Resource for Automated Molecular Microscopy, Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, United States; Speir, Jeffrey A. [National Resource for Automated Molecular Microscopy, Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, United States; Su, Tiffany Y. [Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, United States; Corbett, Kevin D. [Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, United States; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States

    2015-04-28

    The AAA+ family ATPase TRIP13 is a key regulator of meiotic recombination and the spindle assembly checkpoint, acting on signaling proteins of the conserved HORMA domain family. Here we present the structure of the Caenorhabditis elegans TRIP13 ortholog PCH-2, revealing a new family of AAA+ ATPase protein remodelers. PCH-2 possesses a substrate-recognition domain related to those of the protein remodelers NSF and p97, while its overall hexameric architecture and likely structural mechanism bear close similarities to the bacterial protein unfoldase ClpX. We find that TRIP13, aided by the adapter protein p31(comet), converts the HORMA-family spindle checkpoint protein MAD2 from a signaling-active ‘closed’ conformer to an inactive ‘open’ conformer. We propose that TRIP13 and p31(comet) collaborate to inactivate the spindle assembly checkpoint through MAD2 conformational conversion and disassembly of mitotic checkpoint complexes. A parallel HORMA protein disassembly activity likely underlies TRIP13's critical regulatory functions in meiotic chromosome structure and recombination.

  13. Abnormal Events for Emergency Trip in HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Guk Hun; Choi, M. J.; Park, S. I.; Kim, H. W.; Kim, S. J.; Park, J. H.; Kwon, I. C

    2006-12-15

    This report gathers abnormal events related to emergency trip of HANARO that happened during its operation over 10 years since the first criticality on February 1995. The collected examples will be utilized to the HANARO's operators as a useful guide.

  14. Development of a cause analysis system for a CPCS trip by using the rule-base deduction method.

    Science.gov (United States)

    Park, Je-Yun; Koo, In-Soo; Sohn, Chang-Ho; Kim, Jung-Seon; Cho, Gi-Ho; Park, Hee-Seok

    2009-07-01

    A Core Protection Calculator System (CPCS) was developed to initiate a Reactor Trip under the circumstance of certain transients by a Combustion Engineering Company. The major function of the Core Protection Calculator System is to generate contact outputs for the Departure from Nucleate Boiling Ratio (DNBR) Trip and a Local Power Density (LPD) Trip. But in a Core Protection Calculator System, a trip cause cannot be identified, thus only trip signals are transferred to the Plant Protection System (PPS) and only the trip status is displayed. It could take a considerable amount of time and effort for a plant operator to analyze the trip causes of a Core Protection Calculator System. So, a Cause Analysis System for a Core Protection Calculator System (CASCPCS) has been developed by using the rule-base deduction method to assist operators in a Nuclear Power Plant. CASCPCS consists of three major parts. Inference engine has a role of controlling the searching knowledge base, executing the rules and tracking the inference process by using the depth-first searching method. Knowledge base consists of four major parts: rules, data base constants, trip buffer variables and causes. And a user interface is implemented by using menu-driven and window display techniques. The advantage of CASCPCS is that it saves time and effort to diagnose the trip causes of a Core Protection Calculator System, it increases a plant's availability and reliability, and it makes it easy to manage CASCPCS because of using only a cursor control.

  15. Taking the Student to the World: Teaching Sensitive Issues Using Field Trips

    Science.gov (United States)

    Short, Fay; Lloyd, Tracey

    2017-01-01

    Field trips can provide an opportunity to take the student to the world, as an alternative to presenting the world to the student in the classroom. Such trips can create a forum for exploring controversial and distressing topics by exposing the students to first-hand experience, rather than second-hand accounts: witnessing the effects of blind…

  16. Scaling up the mining of semantically-enriched trajectories: TripBuilder at the world level

    OpenAIRE

    Brilhante, Igo; Macedo, Jose Antonio; Nardini, Franco Maria; Perego, Raffaele; Renso, Chiara

    2015-01-01

    TripBuilder is an unsupervised system helping tourists to build their own personalized sightseeing tour [1,3,2]. Given a target touristic city, the time available for the visit, and the tourist's profile, TripBuilder provides a time-budgeted tour that maximizes tourist's interests and takes into account both the time needed to enjoy the at- tractions and to move from one Point of Interest (PoI) to the next one. The knowledge base feeding the sightseeing tour generation algorithm of TripBuilde...

  17. SnapVideo: Personalized Video Generation for a Sightseeing Trip.

    Science.gov (United States)

    Zhang, Luming; Jing, Peiguang; Su, Yuting; Zhang, Chao; Shaoz, Ling

    2017-11-01

    Leisure tourism is an indispensable activity in urban people's life. Due to the popularity of intelligent mobile devices, a large number of photos and videos are recorded during a trip. Therefore, the ability to vividly and interestingly display these media data is a useful technique. In this paper, we propose SnapVideo, a new method that intelligently converts a personal album describing of a trip into a comprehensive, aesthetically pleasing, and coherent video clip. The proposed framework contains three main components. The scenic spot identification model first personalizes the video clips based on multiple prespecified audience classes. We then search for some auxiliary related videos from YouTube 1 according to the selected photos. To comprehensively describe a scenery, the view generation module clusters the crawled video frames into a number of views. Finally, a probabilistic model is developed to fit the frames from multiple views into an aesthetically pleasing and coherent video clip, which optimally captures the semantics of a sightseeing trip. Extensive user studies demonstrated the competitiveness of our method from an aesthetic point of view. Moreover, quantitative analysis reflects that semantically important spots are well preserved in the final video clip. 1 https://www.youtube.com/.

  18. Automatic Trip Detection with the Dutch Mobile Mobility Panel: Towards Reliable Multiple-Week Trip Registration for Large Samples

    NARCIS (Netherlands)

    Thomas, Tom; Geurs, Karst T.; Koolwaaij, Johan; Bijlsma, Marcel E.

    2018-01-01

    This paper examines the accuracy of trip and mode choice detection of the last wave of the Dutch Mobile Mobility Panel, a large-scale three-year, smartphone-based travel survey. Departure and arrival times, origins, destinations, modes, and travel purposes were recorded during a four week period in

  19. Optical fiber imaging for high speed plasma motion diagnostics: Applied to low voltage circuit breakers

    International Nuclear Information System (INIS)

    McBride, J. W.; Balestrero, A.; Tribulato, G.; Ghezzi, L.; Cross, K. J.

    2010-01-01

    An integrated portable measurement system is described for the study of high speed and high temperature unsteady plasma flows such as those found in the vicinity of high current switching arcs. An array of optical fibers allows the formation of low spatial resolution images, with a maximum capture rate of 1x10 6 images per second (1 MHz), with 8 bit intensity resolution. Novel software techniques are reported to allow imaging of the arc; and to measure arc trajectories. Results are presented on high current (2 kA) discharge events in a model test fixture and on the application to a commercial low voltage circuit breaker.

  20. Leisure/Crime, Immaterial Labor, and the Performance of the Teenage Girl in Harmony Korine’s Spring Breakers and Sofia Coppola’s The Bling Ring

    NARCIS (Netherlands)

    Wilkinson, M.

    2017-01-01

    Harmony Korine’s Spring Breakers (2012) and Sofia Coppola’s The Bling Ring (2013) introduced audiences to girls exploring criminal behavior both for and as leisure. The films introduce an idea of leisure/crime: criminal acts that appear to develop as natural, fruitful extensions of leisure

  1. Planning a pharmacy-led medical mission trip, part 2: servant leadership and team dynamics.

    Science.gov (United States)

    Brown, Dana A; Brown, Daniel L; Yocum, Christine K

    2012-06-01

    While pharmacy curricula can prepare students for the cognitive domains of pharmacy practice, mastery of the affective aspects can prove to be more challenging. At the Gregory School of Pharmacy, medical mission trips have been highly effective means of impacting student attitudes and beliefs. Specifically, these trips have led to transformational changes in student leadership capacity, turning an act of service into an act of influence. Additionally, building team unity is invaluable to the overall effectiveness of the trip. Pre-trip preparation for teams includes activities such as routine team meetings, team-building activities, and implementation of committees, as a means of promoting positive team dynamics. While in the field, team dynamics can be fostered through activities such as daily debriefing sessions, team disclosure times, and provision of medical services.

  2. Analysis methodology for the post-trip return to power steam line break event

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chul Shin; Kim, Chul Woo; You, Hyung Keun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-06-01

    An analysis for Steam Line Break (SLB) events which result in a Return-to-Power (RTP) condition after reactor trip was performed for a postulated Yonggwang Nuclear Power Plant Unit 3 cycle 8. Analysis methodology for post-trip RTP SLB is quite different from that of non-RTP SLB and is more difficult. Therefore, it is necessary to develop a methodology to analyze the response of the NSSS parameters to the post-trip RTP SLB events and the fuel performance after the total reactivity exceeds the criticality. In this analysis, the cases with and without offsite power were simulated crediting 3-D reactivity feedback effect due to a local heatup in the vicinity of stuck CEA and compared with the cases without 3-D reactivity feedback with respect to post-trip fuel performance. Departure-to Nucleate Boiling Ratio (DNBR) and Linear Heat Generation Rate (LHGR). 36 tabs., 32 figs., 11 refs. (Author) .new.

  3. Simulation of the Process of Arc Energy-Effect in High Voltage Auto-Expansion SF6 Circuit Breaker

    International Nuclear Information System (INIS)

    Rong Mingzhe; Yang Qian; Fan Chunduo

    2005-01-01

    A new magnetic hydro-dynamics (MHD) model of arc in H.V. auto-expansion SF 6 circuit breaker that takes into consideration nozzle ablation due to both radiation and thermal conduction is presented in this paper. The effect of PTFE (polytetrafluorethylene) vapor is considered in the mass, momentum and energy conservation equations of the constructed model. Then, the gas flow fields with and without conduction considered are simulated. By comparing the aforementioned two results, it is indicated that the arc's maximal temperature with conduction considered is 90 percent of that without considering conduction

  4. Numerical study of turbulence-influence mechanism on arc characteristics in an air direct current circuit breaker

    Science.gov (United States)

    Wu, Mingliang; Yang, Fei; Rong, Mingzhe; Wu, Yi; Qi, Yang; Cui, Yufei; Liu, Zirui; Guo, Anxiang

    2016-04-01

    This paper focuses on the numerical investigation of arc characteristics in an air direct current circuit breaker (air DCCB). Using magneto-hydrodynamics (MHD) theory, 3D laminar model and turbulence model are constructed and calculated. The standard k-epsilon model is utilized to consider the turbulence effect in the arc chamber of the DCCB. Several important phenomena are found: the arc column in the turbulence-model case is more extensive, moves much more slowly than the counterpart in the laminar-model case, and shows stagnation at the entrance of the chamber, unlike in the laminar-model case. Moreover, the arc voltage in the turbulence-model case is much lower than in the laminar-model case. However, the results in the turbulence-model case show a much better agreement with the results of the breaking experiments under DC condition than in the laminar-model case, which is contradictory to the previous conclusions from the arc researches of both the low-voltage circuit breaker and the sulfur hexafluoride (SF6) nozzle. First, in the previous air-arc research of the low-voltage circuit breaker, it is assumed that the air plasma inside the chamber is in the state of laminar, and the laminar-model application gives quite satisfactory results compared with the experiments, while in this paper, the laminar-model application works badly. Second, the turbulence-model application in the arc research of the SF6-nozzle performs much better and gives higher arc voltage than the laminar-model application does, whereas in this paper, the turbulence-model application predicts lower arc voltage than the laminar-model application does. Based on the analysis of simulation results in detail, the mechanism of the above phenomena is revealed. The transport coefficients are strongly changed by turbulence, which will enhance the arc diffusion and make the arc volume much larger. Consequently, the arc appearance and the distribution of Lorentz force in the turbulence-model case

  5. Numerical study of turbulence-influence mechanism on arc characteristics in an air direct current circuit breaker

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Mingliang; Yang, Fei, E-mail: yfei2007@mail.xjtu.edu.cn; Rong, Mingzhe; Wu, Yi; Qi, Yang; Cui, Yufei [State Key Lab of Electrical Insulation and Power Equipment, School of Electrical Engineering, Xi' an Jiaotong University, Xi' an Shaanxi 710049 (China); Liu, Zirui [State Grid Shaanxi Electric Power Company, Xi' an, Shaanxi (China); Guo, Anxiang [Electric Power Research Institute of State Grid Shaanxi Electric Power Company, Xi' an, Shaanxi (China)

    2016-04-15

    This paper focuses on the numerical investigation of arc characteristics in an air direct current circuit breaker (air DCCB). Using magneto-hydrodynamics (MHD) theory, 3D laminar model and turbulence model are constructed and calculated. The standard k-epsilon model is utilized to consider the turbulence effect in the arc chamber of the DCCB. Several important phenomena are found: the arc column in the turbulence-model case is more extensive, moves much more slowly than the counterpart in the laminar-model case, and shows stagnation at the entrance of the chamber, unlike in the laminar-model case. Moreover, the arc voltage in the turbulence-model case is much lower than in the laminar-model case. However, the results in the turbulence-model case show a much better agreement with the results of the breaking experiments under DC condition than in the laminar-model case, which is contradictory to the previous conclusions from the arc researches of both the low-voltage circuit breaker and the sulfur hexafluoride (SF6) nozzle. First, in the previous air-arc research of the low-voltage circuit breaker, it is assumed that the air plasma inside the chamber is in the state of laminar, and the laminar-model application gives quite satisfactory results compared with the experiments, while in this paper, the laminar-model application works badly. Second, the turbulence-model application in the arc research of the SF6-nozzle performs much better and gives higher arc voltage than the laminar-model application does, whereas in this paper, the turbulence-model application predicts lower arc voltage than the laminar-model application does. Based on the analysis of simulation results in detail, the mechanism of the above phenomena is revealed. The transport coefficients are strongly changed by turbulence, which will enhance the arc diffusion and make the arc volume much larger. Consequently, the arc appearance and the distribution of Lorentz force in the turbulence-model case

  6. Estimation of acceptable beam trip frequencies of accelerators for ADS and comparison with performances of existing accelerators

    International Nuclear Information System (INIS)

    Takei, Hayanori; Tsujimoto, Kazufumi; Nishihara, Kenji; Furukawa, Kazuro; Yano, Yoshiharu; Ogawa, Yujiro; Oigawa, Hiroyuki

    2009-09-01

    Frequent beam trips as experienced in existing high power proton accelerators may cause thermal fatigue problems in ADS components which may lead to degradation of their structural integrity and reduction of their lifetime. Thermal transient analyses were performed to investigate the effects of beam trips on the reactor components, with the objective of formulating ADS design that had higher engineering possibilities and determining the requirements for accelerator reliability. These analyses were made on the thermal responses of four parts of the reactor components; the beam window, the cladding tube, the inner barrel and the reactor vessel. Our results indicated that the acceptable frequency of beam trips ranged from 50 to 2x10 4 times per year depending on the beam trip duration. As the beam trips for durations exceeding five minutes were assumed to make the plant shut down and restart, the plant availability was estimated to be 70%. In order to consider measures to reduce the frequency of beam trips on the high power accelerator for ADS, we compared the acceptable frequency of beam trips with the operation data of existing accelerators. The result of this comparison showed that for typical conditions the beam trip frequency for durations of 10 seconds or less was within the acceptable level, while that exceeding five minutes should be reduced to about 1/30 to satisfy the thermal stress conditions. (author)

  7. Spatial interaction models from Irish commuting data: variations in trip length by occupation and gender

    Science.gov (United States)

    O'Kelly, Morton E.; Niedzielski, Michael A.; Gleeson, Justin

    2012-10-01

    Core and peripheral contrasts in journey-to-work trip length can be interpreted as imputing the relative value of origin and destination accessibility (yielding theoretical proxies for rent and wages). Because the main variables are shown to be critically dependent on spatial structure, they may be interpreted as showing the shadow prices due to comparative location. There is also a unifying connection between these results and the existing literature on many dimensions: rent gradients, accessibility, and emissivity. In an empirical example, the advantages of a panoramic view of national commuting statistics are shown, using an Irish data set. Variations in the rates of participation in trip making by location, occupation, and gender are examined. Places that emit more trips than would be expected from their relative location are identified. Further, examining ways in which such emissivity is sensitive to a change in trip length highlights the regions where trips could possibly be adjusted to produce a shorter average trip length or which might be especially sensitive to reduction in employment. A careful reinterpretation of one of the key outputs from a calibrated spatial interaction model is shown to be consistent with the declining rent gradient expected from Alonso's theory of land use.

  8. Influence of chloride ion concentration on the corrosion behavior of Al-bearing TRIP steels

    Energy Technology Data Exchange (ETDEWEB)

    El-Taib Heakal, F., E-mail: fakihaheakal@yahoo.com [Chemistry Department, Faculty of Science, Cairo University, Giza 12613 (Egypt); Tantawy, N.S. [Chemistry Department, Girl' s College for Arts, Science and Education, Ain Shams University, Cairo (Egypt); Shehta, O.S. [Physical Chemistry Department, National Research Centre, Dokki, Giza (Egypt)

    2011-10-17

    Highlights: {yields} Systematic increase of chloride concentration has a critical influence on TRIP steel corrosion. {yields} TRIP microalloyed with Nb and Cr showed lower corrosion rate and smaller threshold Cl{sup -} value. {yields} Increasing Al content by 220 times in the TRIP deteriorates its corrosion behavior. {yields} Impedance results and surface examinations confirmed the obtained results. - Abstract: The effect of a systematic increase of chloride ion concentration on the electrochemical corrosion behavior of two types of Al-bearing TRIP steels (T{sub 1} and T{sub 2}) was studied in aqueous NaCl solutions. Several electrochemical techniques were used comprising open circuit potential measurements, potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS). Chloride concentration has a critical influence on the corrosion rate of the two tested steel samples. For both steels the corrosion rate first increased with increasing chloride content up to a certain critical concentration (CC), and then decreased in solution with chloride level higher than the threshold value. TRIP steel T{sub 1} microalloyed with Nb and Cr as compared to steel T{sub 2} not containing these two elements, exhibited lower corrosion rate and smaller CC value, indicating better corrosion resistance to chloride attack, albeit the Al content in T{sub 2} is 220 times higher than that in T{sub 1}. This is because Nb alloyed with TRIP steel likely enhances the formation on the surface of a stable rust layer enriched with other passivating elements Al, Cu, Cr and Ni, which has higher corrosion resistance and hence improve greatly the passive performance of the TRIP sample. The ac impedance data are in good agreement with the OCP and dc polarization measurements. Surface examinations via scanning electron microscope confirmed well the obtained results.

  9. Influence of chloride ion concentration on the corrosion behavior of Al-bearing TRIP steels

    International Nuclear Information System (INIS)

    El-Taib Heakal, F.; Tantawy, N.S.; Shehta, O.S.

    2011-01-01

    Highlights: → Systematic increase of chloride concentration has a critical influence on TRIP steel corrosion. → TRIP microalloyed with Nb and Cr showed lower corrosion rate and smaller threshold Cl - value. → Increasing Al content by 220 times in the TRIP deteriorates its corrosion behavior. → Impedance results and surface examinations confirmed the obtained results. - Abstract: The effect of a systematic increase of chloride ion concentration on the electrochemical corrosion behavior of two types of Al-bearing TRIP steels (T 1 and T 2 ) was studied in aqueous NaCl solutions. Several electrochemical techniques were used comprising open circuit potential measurements, potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS). Chloride concentration has a critical influence on the corrosion rate of the two tested steel samples. For both steels the corrosion rate first increased with increasing chloride content up to a certain critical concentration (CC), and then decreased in solution with chloride level higher than the threshold value. TRIP steel T 1 microalloyed with Nb and Cr as compared to steel T 2 not containing these two elements, exhibited lower corrosion rate and smaller CC value, indicating better corrosion resistance to chloride attack, albeit the Al content in T 2 is 220 times higher than that in T 1 . This is because Nb alloyed with TRIP steel likely enhances the formation on the surface of a stable rust layer enriched with other passivating elements Al, Cu, Cr and Ni, which has higher corrosion resistance and hence improve greatly the passive performance of the TRIP sample. The ac impedance data are in good agreement with the OCP and dc polarization measurements. Surface examinations via scanning electron microscope confirmed well the obtained results.

  10. The FieldTrip-SimBio pipeline for EEG forward solutions.

    Science.gov (United States)

    Vorwerk, Johannes; Oostenveld, Robert; Piastra, Maria Carla; Magyari, Lilla; Wolters, Carsten H

    2018-03-27

    Accurately solving the electroencephalography (EEG) forward problem is crucial for precise EEG source analysis. Previous studies have shown that the use of multicompartment head models in combination with the finite element method (FEM) can yield high accuracies both numerically and with regard to the geometrical approximation of the human head. However, the workload for the generation of multicompartment head models has often been too high and the use of publicly available FEM implementations too complicated for a wider application of FEM in research studies. In this paper, we present a MATLAB-based pipeline that aims to resolve this lack of easy-to-use integrated software solutions. The presented pipeline allows for the easy application of five-compartment head models with the FEM within the FieldTrip toolbox for EEG source analysis. The FEM from the SimBio toolbox, more specifically the St. Venant approach, was integrated into the FieldTrip toolbox. We give a short sketch of the implementation and its application, and we perform a source localization of somatosensory evoked potentials (SEPs) using this pipeline. We then evaluate the accuracy that can be achieved using the automatically generated five-compartment hexahedral head model [skin, skull, cerebrospinal fluid (CSF), gray matter, white matter] in comparison to a highly accurate tetrahedral head model that was generated on the basis of a semiautomatic segmentation with very careful and time-consuming manual corrections. The source analysis of the SEP data correctly localizes the P20 component and achieves a high goodness of fit. The subsequent comparison to the highly detailed tetrahedral head model shows that the automatically generated five-compartment head model performs about as well as a highly detailed four-compartment head model (skin, skull, CSF, brain). This is a significant improvement in comparison to a three-compartment head model, which is frequently used in praxis, since the importance of

  11. Additive Benefits of Twice Forest Bathing Trips in Elderly Patients with Chronic Heart Failure.

    Science.gov (United States)

    Mao, Gen Xiang; Cao, Yong Bao; Yang, Yan; Chen, Zhuo Mei; Dong, Jian Hua; Chen, Sha Sha; Wu, Qing; Lyu, Xiao Ling; Jia, Bing Bing; Yan, Jing; Wang, Guo Fu

    2018-02-01

    Chronic heart failure (CHF), a clinical syndrome resulting from the consequences of various cardiovascular diseases (CVDs), is increasingly becoming a global cause of morbidity and mortality. We had earlier demonstrated that a 4-day forest bathing trip can provide an adjunctive therapeutic influence on patients with CHF. To further investigate the duration of the impact and the optimal frequency of forest bathing trips in patients with CHF, we recruited those subjects who had experienced the first forest bathing trip again after 4 weeks and randomly categorized them into two groups, namely, the urban control group (city) and the forest bathing group (forest). After a second 4-day forest bathing trip, we observed a steady decline in the brain natriuretic peptide levels, a biomarker of heart failure, and an attenuated inflammatory response as well as oxidative stress. Thus, this exploratory study demonstrated the additive benefits of twice forest bathing trips in elderly patients with CHF, which could further pave the way for analyzing the effects of such interventions in CVDs. Copyright © 2018 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  12. A Review of Research on School Field Trips and Their Value in Education

    Science.gov (United States)

    Behrendt, Marc; Franklin, Teresa

    2014-01-01

    The purpose of this paper is to examine the importance of science field trips as educational tools to connect students to classroom concepts. Experiential learning at formal and informal field trip venues increases student interest, knowledge, and motivation. The teacher's role in preplanning, implementation, and reflection often dictates the…

  13. THE EFFECTIVENESS OF A VIRTUAL FIELD TRIP (VFT MODULE IN LEARNING BIOLOGY

    Directory of Open Access Journals (Sweden)

    Norbaizura HARIS

    2015-07-01

    Full Text Available Virtual Field Trip is a computer aided module of science developed to study the Colonisation and Succession in Mangrove Swamps, as an alternative to the real field trip in Form for Biology. This study is to identify the effectiveness of the Virtual Field Trip (VFT module towards the level of achievement in the formative test for this topic. This study was conducted to 60 students employing a quasi-experimental design involving a treatment group taught using the VFT module and a control group who were taught using conventional methods. Analysis into the effectiveness of the virtual module was done descriptively, followed by inferential analysis involving the two-way ANOVA. The results showed significant differences in the mean scores of pre and post achievement between students taught using VFT and students who were taught using conventional methods for objective, structure and essay type questions. The study concluded that teaching and learning by using the VFT module, integrated with ICT, has a positive impact on student achievement whencompared to conventional methods. This study focuses on the use of the VFT recognizing that teachers are often unable to conduct a real field trip on location.

  14. Spreading Geodiversity awareness in schools through field trips and ICT

    Science.gov (United States)

    Magagna, Alessandra; Giardino, Marco; Ferrero, Elena

    2014-05-01

    Geodiversity, unlike Biodiversity, is not a topic included in the Italian schools curriculum. Nevertheless, Geomorphology is taught at all levels, and it seems to be the right tool for introducing the students to the concepts related to Geodiversity. In this context, a research on the use of field trips and Information and Communication Technologies (ICT) is being carried out for spreading the value of Geodiversity in Secondary Schools. Relevant international literature states that field trips are effective didactic tools for Earth Science education, because they stimulate an active learning process and allow students to appreciate the geological complexity of an area. On the other side, ICT allow students to get knowledge about the variety of landforms of their own territory by staying indoor, using virtual field trips and free software like Google Earth, Google Maps, Bing etc. In order to connect the two strategies, an innovative educational project is proposed here; it involves both the indoor and the outdoor activities, by enhancing a critical approach to the complexity of geological processes. As a starting point, a multimedia product on 20 Italian geological tours, designed for analyzing Geodiversity at a regional scale, has been tested with teachers and students, in order to understand its effectiveness by using it solely indoor. In a second phase, teachers and students have been proposed to compare and integrate indoor and outdoor activities to approach Geodiversity directly at a local scale, by means of targeted field trips. For achieving this goal, during the field trips, students used their mobile devices (smartphone and tablet) equipped with free and/or open source applications (Epicollect, Trimble Outdoor Navigator). These tools allow to track field trips, to gather data (geomorphological observations and related photographs), and to elaborate them in the laboratory; a process useful for reasoning on concepts such as spatial and temporal scales and for

  15. Hawaii Longline Fishery Trip Expenditure (2004 to present)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a time-series dataset of trip expenditure data for the Hawaii-based longline fleet for the period August 2004 to present. The data collection includes 10...

  16. The trip status and the reduction countermeasure in Kori nuclear power plant unit 1 and 2

    International Nuclear Information System (INIS)

    Kim, Jung-Soo

    1991-01-01

    Nuclear power account for 36% of Korea's total electric capacity and provided over 50% of the net electric power supply by June 1991. These plants supply US with the cheapest and most stable electric supply available. However each units capacity is very large and a plant trip due to failure of a component or a human error has a great influence on the nations electric power supply and drastically decreases the reserve margin. This report will analyze the trip causes and measure the trip frequency from the first commercial operation of Kori unit 1 and 2 to the end of June 1991, reflect to the plant operation, management and facility modification, etc. This will minimize the number of trips or urgent power reductions and thus contribute to an increase in plant capacity factor and safety, and stabilize the electric power demand and supply. The safety and the economy of nuclear power plant have to be secured and raised respectably by increasing the capacity factor. Since the prevention of trips plays an important role in the plant safety and economy, we have to do our best to prevent the unexpected trip

  17. Discrete-Choice Modeling Of Non-Working Women’s Trip-Chaining Activity Based

    Science.gov (United States)

    Hayati, Amelia; Pradono; Purboyo, Heru; Maryati, Sri

    2018-05-01

    Start The urban developments of technology and economics are now changing the lifestyles of the urban societies. It is also changing their travel demand to meet their movement needs. Nowadays, urban women, especially in Bandung, West Java, have a high demand for their daily travel and tend to increase. They have the ease of accessibility to personal modes of transportation and freedom to go anywhere to meet their personal and family needs. This also happens to non-working women or as housewives in the city of Bandung. More than 50% of women’s mobility is outside the home, in the term of trip-chaining, from leaving to returning home in one day. It is based on their complex activities in order to meet the needs of family and home care. While less than 60% of male’s mobility is outdoors, it is a simple trip-chaining or only has a single trip. The trip-chaining has significant differences between non-working women and working-men. This illustrates the pattern of Mom and Dad’s mobility in a family with an activity-based approach for the same purpose, i.e. family welfare. This study explains how complex the trip-chaining of non-working urban women and as housewives, with an activity-based approach done outdoors in a week. Socio-economic and household demographic variables serve as the basis for measuring the independent variables affecting family welfare, as well as the variables of type, time and duration of activities performed by unemployed housewives. This study aims to examine the interrelationships between activity variables, especially the time of activity and travel, and socio-economic of household variables that can generate the complexity of women’s daily travel. Discrete Choice Modeling developed by Ben-Akiva, Chandra Bhat, etc., is used in this study to illustrate the relationship between activity and socio-economic demographic variables based on primary survey data in Bandung, West Java for 466 unemployed housewives. The results of the regression, by

  18. The ice-breaker effect: singing mediates fast social bonding.

    Science.gov (United States)

    Pearce, Eiluned; Launay, Jacques; Dunbar, Robin I M

    2015-10-01

    It has been proposed that singing evolved to facilitate social cohesion. However, it remains unclear whether bonding arises out of properties intrinsic to singing or whether any social engagement can have a similar effect. Furthermore, previous research has used one-off singing sessions without exploring the emergence of social bonding over time. In this semi-naturalistic study, we followed newly formed singing and non-singing (crafts or creative writing) adult education classes over seven months. Participants rated their closeness to their group and their affect, and were given a proxy measure of endorphin release, before and after their class, at three timepoints (months 1, 3 and 7). We show that although singers and non-singers felt equally connected by timepoint 3, singers experienced much faster bonding: singers demonstrated a significantly greater increase in closeness at timepoint 1, but the more gradual increase shown by non-singers caught up over time. This represents the first evidence for an 'ice-breaker effect' of singing in promoting fast cohesion between unfamiliar individuals, which bypasses the need for personal knowledge of group members gained through prolonged interaction. We argue that singing may have evolved to quickly bond large human groups of relative strangers, potentially through encouraging willingness to coordinate by enhancing positive affect.

  19. Understanding Social Learning Behaviors via a Virtual Field Trip

    Directory of Open Access Journals (Sweden)

    Xin Bai

    2014-06-01

    Full Text Available This is a multidisciplinary study investigating how a virtual rather than face-to-face field trip can be conducted in a real-world setting and how students respond to such a social learning opportunity. Our participants followed a story of a stroke patient at her virtual home and in a virtual hospital via a teaching vignette. They were then given a new case and got on a virtual trip via a multiuser virtual environment. They played the roles of patients, relatives, doctors, or nurses, experiencing the emotional, physical, or social impacts those stakeholders may go through. Our study finds the overall participation of the Virtual Group is 50% more than the Text Group. Although the Virtual Group generates much more nodes in total, they focused much less on knowledge sharing and comparing than the Text Group (46 vs. 67, but more on other higher-level aspects of social interactions, such as knowledge discovery (57 vs. 42, co-construction (66 vs. 39, testing and modification (58 vs. 24 and application of newly constructed meaning (60 vs. 16. Analysis of students’ virtual field activities and in-depth discussions of important issues implied are included to help understand social learning behaviors during a virtual field trip. Sustainability of such systems is discussed.

  20. A simplified approach to detect undervoltage tripping of wind generators

    Energy Technology Data Exchange (ETDEWEB)

    Sigrist, Lukas; Rouco, Luis [Universidad Pontificia Comillas, Madrid (Spain). Inst. de Investigacion Tecnologica

    2012-07-01

    This paper proposes a simplified but fast approach based on a Norton equivalent of wind generators to detect undervoltage tripping of wind generators. This approach is successfully applied to a real wind farm. The relevant grid code requires the wind farm to withstand a voltage dip of 0% retained voltage. The ability of the wind generators to raise the voltage supplying reactive current and to avoid undervoltage tripping is investigated. The obtained results are also compared with the results obtained from detailed dynamic simulations, which make use of wind generator models complying with the relevant grid code. (orig.)

  1. Health Effect of Forest Bathing Trip on Elderly Patients with Chronic Obstructive Pulmonary Disease.

    Science.gov (United States)

    Jia, Bing Bing; Yang, Zhou Xin; Mao, Gen Xiang; Lyu, Yuan Dong; Wen, Xiao Lin; Xu, Wei Hong; Lyu, Xiao Ling; Cao, Yong Bao; Wang, Guo Fu

    2016-03-01

    Forest bathing trip is a short, leisurely visit to forest. In this study we determined the health effects of forest bathing trip on elderly patients with chronic obstructive pulmonary disease (COPD). The patients were randomly divided into two groups. One group was sent to forest, and the other was sent to an urban area as control. Flow cytometry, ELISA, and profile of mood states (POMS) evaluation were performed. In the forest group, we found a significant decrease of perforin and granzyme B expressions, accompanied by decreased levels of pro-inflammatory cytokines and stress hormones. Meanwhile, the scores in the negative subscales of POMS decreased after forest bathing trip. These results indicate that forest bathing trip has health effect on elderly COPD patients by reducing inflammation and stress level. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  2. A neural networks based ``trip`` analysis system for PWR-type reactors; Um sistema de analise de ``trip`` em reatores PWR usando redes neuronais

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Antonio Carlos Pinto Dias

    1993-12-31

    The analysis short after automatic shutdown (trip) of a PWR-type nuclear reactor takes a considerable amount of time, not only because of the great number of variables involved in transients, but also the various equipment that compose a reactor of this kind. On the other hand, the transients`inter-relationship, intended to the detection of the type of the accident is an arduous task, since some of these accidents (like loss of FEEDWATER and station BLACKOUT, for example), generate transients similar in behavior (as cold leg temperature and steam generators mixture levels, for example). Also, the sequence-of-events analysis is not always sufficient for correctly pin point the causes of the trip. (author) 11 refs., 39 figs.

  3. A neural networks based ``trip`` analysis system for PWR-type reactors; Um sistema de analise de ``trip`` em reatores PWR usando redes neuronais

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Antonio Carlos Pinto Dias

    1994-12-31

    The analysis short after automatic shutdown (trip) of a PWR-type nuclear reactor takes a considerable amount of time, not only because of the great number of variables involved in transients, but also the various equipment that compose a reactor of this kind. On the other hand, the transients`inter-relationship, intended to the detection of the type of the accident is an arduous task, since some of these accidents (like loss of FEEDWATER and station BLACKOUT, for example), generate transients similar in behavior (as cold leg temperature and steam generators mixture levels, for example). Also, the sequence-of-events analysis is not always sufficient for correctly pin point the causes of the trip. (author) 11 refs., 39 figs.

  4. 50 CFR 660.332 - Open access daily trip limit (DTL) fishery for sablefish.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Open access daily trip limit (DTL) fishery... COAST STATES West Coast Groundfish-Open Access Fisheries § 660.332 Open access daily trip limit (DTL) fishery for sablefish. (a) Open access DTL fisheries both north and south of 36° N. lat. Open access...

  5. Gait Characteristics Associated with Trip-Induced Falls on Level and Sloped Irregular Surfaces

    Directory of Open Access Journals (Sweden)

    Andrew Merryweather

    2011-11-01

    Full Text Available Same level falls continue to contribute to an alarming number of slip/trip/fall injuries in the mining workforce. The objective of this study was to investigate how walking on different surface types and transverse slopes influences gait parameters that may be associated with a trip event. Gait analysis was performed for ten subjects on two orientations (level and sloped on smooth, hard surface (control and irregular (gravel, larger rocks surfaces. Walking on irregular surfaces significantly increased toe clearance compared to walking on the smooth surface. There was a significant (p < 0.05 decrease in cadence (steps/min, stride length (m, and speed (m/s from control to gravel to larger rocks. Significant changes in external rotation and increased knee flexion while walking on irregular surfaces were observed. Toe and heel clearance requirements increased on irregular surfaces, which may provide an explanation for trip-induced falls; however, the gait alterations observed in the experienced workers used as subjects would likely improve stability and recovery from a trip.

  6. CRM1-mediated nuclear export is required for 26 S proteasome-dependent degradation of the TRIP-Br2 proto-oncoprotein.

    Science.gov (United States)

    Cheong, Jit Kong; Gunaratnam, Lakshman; Hsu, Stephen I-Hong

    2008-04-25

    Overexpression of the proto-oncogene TRIP-Br2 (SERTAD2) has been shown to induce E2F activity and promote tumorigenesis, whereas ablation of TRIP-Br2 arrests cell proliferation. Timely degradation of many cell cycle regulators is fundamental to the maintenance of proper cell cycle progression. Here we report novel mechanism(s) that govern the tight regulation of TRIP-Br2 levels during cell cycle progression. TRIP-Br2 was observed to be a short-lived protein in which the expression level peaks at the G(1)/S boundary. TRIP-Br2 accumulated in cells treated with 26 S proteasome inhibitors. Co-immunoprecipitation studies revealed that TRIP-Br2 forms ubiquitin conjugates. In silico analysis identified a putative leucine-rich nuclear export signal (NES) motif that overlaps with the PHD-Bromo interaction domain in the acidic C-terminal transactivation domain (TAD) of TRIP-Br2. This NES motif is highly conserved in widely divergent species and in all TRIP-Br family members. TRIP-Br2 was shown to be stabilized in G(2)/M phase cells through nuclear entrapment, either by deletion of the acidic C-terminal TAD, which includes the NES motif, or by leptomycin B-mediated inhibition of the CRM1-dependent nuclear export machinery. Mutation of leucine residue 238 of this NES motif abolished the interaction between CRM1 and TRIP-Br2, as well as the nuclear export of TRIP-Br2 and its subsequent 26 S proteasome-dependent degradation. These data suggest that CRM1-mediated nuclear export may be required for the proper execution of ubiquitin-proteasome-dependent degradation of TRIP-Br2.

  7. Report on safety related occurrences and reactor trips July 1, 1979 - December 31, 1979

    International Nuclear Information System (INIS)

    Olsson, S.; Andermo, L.

    1980-01-01

    This is a report on all reported safety related occurrences and reactor trips in Swedish nuclear power plants in operation during July 1 to December 31, 1979 inclusive. The facilities involved are Barsebaeck 1 and 2, Oskarshamn 1 and 2 and Ringhals 1 and 2. During this period of 6 months 76 safety related occurrences and 27 reactor trips have been reported to the Nuclear Power Inspectorate. It is to the greatest extent conventional components such as valves and pumps which bring about the safety related occurrences or occurrences leading to outages or power reductions. However, the component errors discovered in the safety related systems have not affected the function of their redundant system and other diverse systems have not been involved. Therefore the reactor safety has been satisfactory. The total number of reactor trips are normal. The average value for these 6 months is 4.5 trips/unit. Approximetely one half of the reactor trips happened at zero or very low power operation. The fact that even small deviations from prescribed operation result in an automatic and safe shut down of the reactor, does not always imply a conflict with operational availability. The greatest outages are caused by occurrences without safety significance. (author)

  8. Effect of weather on pedestrian trip count and duration: City-scale evaluations using mobile phone application data.

    Science.gov (United States)

    Vanky, Anthony P; Verma, Santosh K; Courtney, Theodore K; Santi, Paolo; Ratti, Carlo

    2017-12-01

    We examined the association between meteorological (weather) conditions in a given locale and pedestrian trips frequency and duration, through the use of locative digital data. These associations were determined for seasonality, urban microclimate, and commuting. We analyzed GPS data from a broadly available activity tracking mobile phone application that automatically recorded 247,814 trips from 5432 unique users in Boston and 257,697 trips from 8256 users in San Francisco over a 50-week period. Generally, we observed increased air temperature and the presence of light cloud cover had a positive association with hourly trip frequency in both cities, regardless of seasonality. Temperature and weather conditions generally showed greater associations with weekend and discretionary travel, than with weekday and required travel. Weather conditions had minimal association with the duration of the trip, once the trip was initiated. The observed associations in some cases differed between the two cities. Our study illustrates the opportunity that emerging technology presents to study active transportation, and exposes new methods to wider consideration in preventive medicine.

  9. Three-Dimensional Simulation of Plasma Deformation During Contact Opening in a Circuit Breaker, Including the Analysis of Kink Instability and Sausage Instability

    International Nuclear Information System (INIS)

    Abbasi, Vahid; Gholami, Ahmad; Niayesh, Kaveh

    2012-01-01

    A three-dimensional (3-D) transient model has been developed to investigate plasma deformation driven by a magnetic field and its influence on arc stability in a circuit breaker. The 3-D distribution of electric current density is obtained from a current continuity equation along with the generalized Ohm's law; while the magnetic field induced by the current flowing through the arc column is calculated by the magnetic vector potential equation. When gas interacts with an arc column, fundamental factors, such as Ampere's law, Ohm's law, the turbulence model, transport equations of mass, momentum and energy of plasma flow, have to be coupled for analyzing the phenomenon. The coupled interactions between arc and plasma flow are described in the framework of time-dependent magnetohydrodynamic (MHD) equations in conjunction with a K-ε turbulence model. Simulations have been focused on sausage and kink instabilities in plasma (these phenomena are related to pinch effects and electromagnetic fields). The 3-D simulation reveals the relation between plasma deformation and instability phenomena, which affect arc stability during circuit breaker operation. Plasma deformation is the consequence of coupled interactions between the electromagnetic force and plasma flow described in simulations. (plasma technology)

  10. Effects of RCP trip when recovering HPSI during LOCA in a Westinghouse PWR

    Energy Technology Data Exchange (ETDEWEB)

    Montero-Mayorga, Javier, E-mail: fj.montero@alumnos.upm.es; Queral, César; Rivas-Lewicky, Julio; González-Cadelo, Juan

    2014-12-15

    Highlights: • If HPSI is recovered during SBLOCA and RCPs are tripped core damage can be reached. • If the RCPs are tripped once the accumulators have injected the damage can be avoided. • If only 2 out of 3 RCPs are tripped the damage can be also avoided. • Improvements are proposed to the EOPs in order to avoid possible damage. - Abstract: Current Westinghouse Emergency Operating Procedures (EOPs) indicate initially that the operator must keep the reactor coolant pumps (RCPs) running during a Small Break Loss of Coolant Accident (SBLOCA) if there is unavailability of high pressure safety injection (HPSI) system in order to cool the core by forced convection. However, the crew must follow different EOPs along the transient depending on its evolution. In these EOPs there are several conditions which indicate the necessity of tripping one or more RCPs when HPSI is recovered. In this paper the occurrence of a SBLOCA with unavailability of HPSI has been analyzed with a model of Almaraz Nuclear Power Plant (Westinghouse 3 Loop) for TRACE code V5.0 patch 1. Two different approaches have been considered: the first one, taking into account Optimal Recovery Guidelines (ORGs) and in the second approach, the transition to Function Restoration Guidelines (FRGs) due to inadequate core cooling (ICC) conditions is considered. Results of this paper lead to the implementation of an improvement in current EOPs regarding how many RCPs should be tripped during SBLOCA sequences.

  11. Use of Fuzzy Logic Systems for Assessment of Primary Faults

    Science.gov (United States)

    Petrović, Ivica; Jozsa, Lajos; Baus, Zoran

    2015-09-01

    In electric power systems, grid elements are often subjected to very complex and demanding disturbances or dangerous operating conditions. Determining initial fault or cause of those states is a difficult task. When fault occurs, often it is an imperative to disconnect affected grid element from the grid. This paper contains an overview of possibilities for using fuzzy logic in an assessment of primary faults in the transmission grid. The tool for this task is SCADA system, which is based on information of currents, voltages, events of protection devices and status of circuit breakers in the grid. The function model described with the membership function and fuzzy logic systems will be presented in the paper. For input data, diagnostics system uses information of protection devices tripping, states of circuit breakers and measurements of currents and voltages before and after faults.

  12. Mechanisms influencing student understanding on an outdoor guided field trip

    Science.gov (United States)

    Caskey, Nourah Al-Rashid

    Field trips are a basic and important, yet often overlooked part of the student experience. They provide the opportunity to integrate real world knowledge with classroom learning and student previous personal experiences. Outdoor guided field trips leave students with an increased understanding, awareness and interest and in science. However, the benefits of this experience are ambiguous at best (Falk and Balling, 1982; Falk and Dierking, 1992; Kisiel, 2006.) Students on an outdoor guided field trip to a local nature park experienced a significant increase in their understanding of the rock cycle. The changes in the pre-field trip test and the post-field trip test as well as their answers in interviews showed a profound change in the students' understanding and in their interest in the subject matter. The use of the "student's voice" (Bamberger and Tal, 2008) was the motivation for data analysis. By using the students' voice, I was able to determine the mechanisms that might influence their understanding of a subject. The central concepts emerging from the data were: the outdoor setting; the students' interest; the social interaction. From these central concepts, a conceptual model was developed. The outdoor setting allows for the freedom to explore, touch, smell and movement. This, in turn, leads to an increased interest in subject matter. As the students are exploring, they are enjoying themselves and become more open to learning. Interest leads to a desire to learn (Dewey, 1975). In addition to allowing the freedom to explore and move, the outdoor setting creates the condition for social interaction. The students talk to each other as they walk; they have in-depth discourse regarding the subject matter---with the teachers, each other and with the guides. The guides have an extremely important role in the students' learning. The more successful guides not only act as experts, but also adjust to the students' needs and act or speak accordingly. The

  13. Microstructure-based constitutive modeling of TRIP steel: Prediction of ductility and failure modes under different loading conditions

    International Nuclear Information System (INIS)

    Choi, K.S.; Liu, W.N.; Sun, X.; Khaleel, M.A.

    2009-01-01

    We study the ultimate ductility and failure modes of a commercial transformation-induced plasticity (TRIP) 800 steel under different loading conditions with an advanced microstructure-based finite-element analysis. The representative volume element (RVE) for the TRIP 800 under examination is developed based on an actual microstructure obtained from scanning electron microscopy. The ductile failure of the TRIP 800 under different loading conditions is predicted in the form of plastic strain localization without any prescribed failure criteria for the individual phases. This indicates that the microstructure-level inhomogeneity of the various constituent phases can be the key factor influencing the final ductility of the TRIP 800 steel under different loading conditions. Comparisons of the computational results with experimental measurements suggest that the microstructure-based modeling approach accurately captures the overall macroscopic behavior of the TRIP 800 steel under different loading and boundary conditions.

  14. Insulation co-ordination aspects for power stations with generator circuit-breakers

    International Nuclear Information System (INIS)

    Sanders, M.; Koeppl, G.; Kreuzer, J.

    1995-01-01

    The generator circuit-breaker (gen. c.b.) located between the generator and the step-up transformer, is now being applied world-wide. It has become a recognized electrical component of power stations which is largely due to economical advantages and increased power station availability. Technical protection considerations for power stations have always been the reason for discussion and the object of improvement. With the use of a gen. c.b., some points of view need to be considered anew. Not only the protection system in case of fault conditions will be influenced, but also the insulation co-ordination philosophy. Below the results of some calculations concerning expected overvoltages are presented. These calculations are based on a transformer rated 264/15.5kV, 220 MVA. But the results are transferable to other power plants. Some measurements carried out on a transformer of the same rating complement the calculations. The findings may contribute to an improvement in insulation co-ordination and protection of the electrical system generator--step-up transformer

  15. Sistem Proteksi Arus Bocor Menggunakan Earth Leakage Circuit Breaker Berbasis Arduino

    Directory of Open Access Journals (Sweden)

    Syukriyadin Syukriyadin

    2017-02-01

    Full Text Available Touching a live part of electrical equipment either intentionally or unintentionally can cause an electric shock. The touch can occur directly or indirectly and results in the flow of electric current through the human body to the ground. This electric current is known as the leakage current and can have fatal effects on the human body such as burns, cramps, faint and death. This paper aims to design a prototype protection model of the earth leakage circuit breaker device based on Arduino (ELCBA to protect the human body from the electrical hazards. The performance of the ELCBA is investigated by detecting the earth leakage current to the grounding system (TN.  The prototype is designed and simulated by using Proteus software. Based on the response test carried out on the prototype, it can be concluded that the ELCBA can operate properly to disconnect the electric circuit if the leakage current is detected greater than or equal to 30 mA with a time delay of 15 ms and to reclose the circuit again after 5 minutes.

  16. The Compensation Act 2006 and School Trips

    Science.gov (United States)

    Hunter-Jones, John

    2006-01-01

    The Compensation Act 2006 received its Royal Assent on 25 July 2006. The Act allows the courts to have regard to the social utility of "desirable activities", including school trips, in considering negligence claims. The article reviews the law of negligence as it affects teachers of the very young and considers the possible impact of…

  17. Extending temporary storage capacity with emulsion breakers

    International Nuclear Information System (INIS)

    Buist, I.; Guarino, A.; DeVitis, D.; Nolan, K.; Lewis, A.; Smith, B.; Lane, J.

    2002-01-01

    The use of emulsion breakers injected into an oil spill recovery system was examined in both laboratory testing and at the OHMSETT test facility. The tests were designed to assess the injection/mixing/settling regimes needed for optimum water-removal performance from a meso-stable water-in-oil emulsion with an oil spill demulsifier. Different types of injection locations and mixing technologies were examined, including skimmer heads, cargo lines, tank inlets, as well as static in-line and mechanical technologies. During laboratory testing, water-in-oil emulsions and free water was pumped through various lengths of piping loops, an in-line mixer and 8 settling tanks. Following the injection of a demulsifier, the fluid was decanted to observe the emulsion breaking. At the OHMSETT test facility, a Desmi Terminator skimmer recovered the same emulsion from a polluted water surface. Different slick thicknesses, wave heights and recovery rates were used. A demulsifier was also injected into the recovered fluid which was allowed to separate in recovery tanks. The demulsifier efficiency was then measured. It was determined that the demulsifier significantly reduced the volume of water in the recovery tanks and the water content of the remaining emulsion. If free water content was greater than 60 per cent, then the effect of the surfactant was greatly reduced. If no free water was present, the level of turbulence was insufficient to promote emulsion breaking. More than 33 per cent free water content is needed to reduce the bulk viscosity of the fluid and to promote emulsion breaking. The degree of emulsion breaking also increased with increasing mixing energy. 10 refs., 5 tabs., 8 figs

  18. Investigations on human error hazards in recent unintended trip events of Korean nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sa Kil; Jang, Tong Il; Lee, Yong Hee; Shin, Kwang Hyeon [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    According to the Operational Performance Information System (OPIS) which has been operated to improve the public understanding by the KINS (Korea Institute of Nuclear Safety), unintended trip events by mainly human errors counted up to 38 cases (18.7%) from 2000 to 2011. Although the Nuclear Power Plant (NPP) industry in Korea has been making efforts to reduce the human errors which have largely contributed to trip events, the human error rate might keep increasing. Interestingly, digital based I and C systems is the one of the reduction factors of unintended reactor trips. Human errors, however, have occurred due to the digital based I and C systems because those systems require new or changed behaviors to the NPP operators. Therefore, it is necessary that the investigations of human errors consider a new methodology to find not only tangible behavior but also intangible behavior such as organizational behaviors. In this study we investigated human errors to find latent factors such as decisions and conditions in the all of the unintended reactor trip events during last dozen years. To find them, we applied the HFACS (Human Factors Analysis and Classification System) which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. The objective of this study is to find latent factors behind of human errors in nuclear reactor trip events. Therefore, a method to investigate unintended trip events by human errors and the results will be discussed in more detail.

  19. Investigations on human error hazards in recent unintended trip events of Korean nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Sa Kil; Jang, Tong Il; Lee, Yong Hee; Shin, Kwang Hyeon

    2012-01-01

    According to the Operational Performance Information System (OPIS) which has been operated to improve the public understanding by the KINS (Korea Institute of Nuclear Safety), unintended trip events by mainly human errors counted up to 38 cases (18.7%) from 2000 to 2011. Although the Nuclear Power Plant (NPP) industry in Korea has been making efforts to reduce the human errors which have largely contributed to trip events, the human error rate might keep increasing. Interestingly, digital based I and C systems is the one of the reduction factors of unintended reactor trips. Human errors, however, have occurred due to the digital based I and C systems because those systems require new or changed behaviors to the NPP operators. Therefore, it is necessary that the investigations of human errors consider a new methodology to find not only tangible behavior but also intangible behavior such as organizational behaviors. In this study we investigated human errors to find latent factors such as decisions and conditions in the all of the unintended reactor trip events during last dozen years. To find them, we applied the HFACS (Human Factors Analysis and Classification System) which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. The objective of this study is to find latent factors behind of human errors in nuclear reactor trip events. Therefore, a method to investigate unintended trip events by human errors and the results will be discussed in more detail

  20. Analysis of the equilibrium trip cost accounting for the fuel cost in a single-lane traffic system without late arrival

    Science.gov (United States)

    Tang, Tie-Qiao; Wang, Tao; Chen, Liang; Huang, Hai-Jun

    2018-01-01

    In this paper, we introduce the fuel cost into each commuter's trip cost, define a new trip cost without late arrival and its corresponding equilibrium state, and use a car-following model to explore the impacts of the fuel cost on each commuter's departure time, departure interval, arrival time, arrival interval, traveling time, early arrival time and trip cost at the above equilibrium state. The numerical results show that considering the fuel cost in each commuter's trip cost has positive impacts on his trip cost and fuel cost, and the traffic situation in the system without late arrival, i.e., each commuter should explicitly consider the fuel cost in his trip cost.

  1. Numerical study on effect of boundary layer trips on aerodynamic performance of E216 airfoil

    Directory of Open Access Journals (Sweden)

    B.K. Sreejith

    2018-02-01

    Full Text Available Simulation is carried out to find the performance of airfoil E216 using Transition γ-Reθ model at Reynolds number of 100,000. Flow behaviour and effect of angle of attack (AOA on laminar separation bubble (LSB formation are examined. The results are validated with wind tunnel experimental results. LSB formation is clearly spotted in the velocity vector plot and coefficient of pressure distribution over airfoil. LSB moved upstream towards the leading edge with increase in AOA. Effect of boundary layer trip on LSB formation over the airfoil and performance of airfoil are studied. Two different trip locations, 17% of chord and 10% of chord from leading edge, and different trip heights (0.3 mm, 0.5 mm, 0.7 mm, 1 mm are investigated in this study. Results showed that boundary layer trip could eliminate LSB partially or completely and improve aerodynamic performance of the airfoil. Maximum improvement in drag by 15.48% and lift to drag ratio by 21.62% are obtained at angle of attack of 60. In all the cases, improvement in performance is observed only up to trip height of 0.5 mm.

  2. WTO ministerial conference adopts declaration on TRIPS and public health.

    Science.gov (United States)

    Elliott, Richard

    2002-03-01

    In November 2001, the 4th Ministerial Conference of the World Trade Organization adopted a Ministerial Declaration on public health and the WTO's Agreement on Trade-Related Aspects of Intellectual Property Rights (the "TRIPS Agreement"). The declaration represents a modest advance in addressing concerns that strict patent laws, and threats of trade sanctions, will be a barrier to most of the world's people with HIV/AIDS accessing affordable medicines. The full significance of the declaration remains to be seen, as it depends on what political impact it has at the WTO and on its member countries, and what legal impact it will have in the interpretation of the TRIPS Agreement.

  3. Modelling mode choice in short trips - shifting from car to bicycle

    DEFF Research Database (Denmark)

    Halldórsdóttir, Katrín; Christensen, Linda; Jensen, Thomas Christian

    2011-01-01

    -economic variables of a representative sample of the population. The investigated sample includes 11,072 observations. The model considers five alternatives (i.e., car driver, car passenger, public transport, walk and obviously bike), for which level of service variables are calculated through assignment procedures...... relevance of the cost for short trips. Expectedly, the selection of bicycle as mode for short trips is positively related to owning a bicycle and negatively linked to owning one or more cars. Urban density has also positive correlation with the selection of sustainable transport modes....

  4. Experimental and numerical investigation of the internal kinetics of a surf-zone plunging breaker

    DEFF Research Database (Denmark)

    Emarat, Narumon; Forehand, David I.M.; Christensen, Erik Damgaard

    2012-01-01

    Over the last couple of decades both the qualitative and quantitative understanding of breaking waves in the surf zone have greatly increased. This is due to the advances in experimental and numerical techniques. However, few comparisons between these two different investigative techniques...... for surfzone breaking waves have been reported. In this study, a comparison is made between the experimental and numerical investigation of the internal kinematics of a surf-zone plunging breaker. The full-field velocity measuring technique known as Particle Image Velocimetry (PIV) is used in the experiments...... was found for all comparisons: free-surface elevations, velocity vector maps, velocity profiles and velocity-magnitude contours. However, some small discrepancies were observed. In the free-surface elevation comparisons, a slight time lag was observed in the numerical results and it is suggested...

  5. Effect of weather on pedestrian trip count and duration: City-scale evaluations using mobile phone application data

    Directory of Open Access Journals (Sweden)

    Anthony P. Vanky

    2017-12-01

    Full Text Available We examined the association between meteorological (weather conditions in a given locale and pedestrian trips frequency and duration, through the use of locative digital data. These associations were determined for seasonality, urban microclimate, and commuting. We analyzed GPS data from a broadly available activity tracking mobile phone application that automatically recorded 247,814 trips from 5432 unique users in Boston and 257,697 trips from 8256 users in San Francisco over a 50-week period. Generally, we observed increased air temperature and the presence of light cloud cover had a positive association with hourly trip frequency in both cities, regardless of seasonality. Temperature and weather conditions generally showed greater associations with weekend and discretionary travel, than with weekday and required travel. Weather conditions had minimal association with the duration of the trip, once the trip was initiated. The observed associations in some cases differed between the two cities. Our study illustrates the opportunity that emerging technology presents to study active transportation, and exposes new methods to wider consideration in preventive medicine. Keywords: Weather, Pedestrian activity, Walking, Weather conditions and active transportation, Microclimates, Spatial behavior, Mobile phones, Locative data, Emerging technology, Big data

  6. Modulation of thalamocortical oscillations by TRIP8b, an auxiliary subunit for HCN channels.

    Science.gov (United States)

    Zobeiri, Mehrnoush; Chaudhary, Rahul; Datunashvili, Maia; Heuermann, Robert J; Lüttjohann, Annika; Narayanan, Venu; Balfanz, Sabine; Meuth, Patrick; Chetkovich, Dane M; Pape, Hans-Christian; Baumann, Arnd; van Luijtelaar, Gilles; Budde, Thomas

    2018-04-01

    Hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels have important functions in controlling neuronal excitability and generating rhythmic oscillatory activity. The role of tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b) in regulation of hyperpolarization-activated inward current, I h , in the thalamocortical system and its functional relevance for the physiological thalamocortical oscillations were investigated. A significant decrease in I h current density, in both thalamocortical relay (TC) and cortical pyramidal neurons was found in TRIP8b-deficient mice (TRIP8b -/- ). In addition basal cAMP levels in the brain were found to be decreased while the availability of the fast transient A-type K + current, I A , in TC neurons was increased. These changes were associated with alterations in intrinsic properties and firing patterns of TC neurons, as well as intrathalamic and thalamocortical network oscillations, revealing a significant increase in slow oscillations in the delta frequency range (0.5-4 Hz) during episodes of active-wakefulness. In addition, absence of TRIP8b suppresses the normal desynchronization response of the EEG during the switch from slow-wave sleep to wakefulness. It is concluded that TRIP8b is necessary for the modulation of physiological thalamocortical oscillations due to its direct effect on HCN channel expression in thalamus and cortex and that mechanisms related to reduced cAMP signaling may contribute to the present findings.

  7. Activity time budget during foraging trips of emperor penguins.

    Directory of Open Access Journals (Sweden)

    Shinichi Watanabe

    Full Text Available We developed an automated method using depth and one axis of body acceleration data recorded by animal-borne data loggers to identify activities of penguins over long-term deployments. Using this technique, we evaluated the activity time budget of emperor penguins (n = 10 both in water and on sea ice during foraging trips in chick-rearing season. During the foraging trips, emperor penguins alternated dive bouts (4.8 ± 4.5 h and rest periods on sea ice (2.5 ± 2.3 h. After recorder deployment and release near the colony, the birds spent 17.9 ± 8.4% of their time traveling until they reached the ice edge. Once at the ice edge, they stayed there more than 4 hours before the first dive. After the first dive, the mean proportions of time spent on the ice and in water were 30.8 ± 7.4% and 69.2 ± 7.4%, respectively. When in the water, they spent 67.9 ± 3.1% of time making dives deeper than 5 m. Dive activity had no typical diurnal pattern for individual birds. While in the water between dives, the birds had short resting periods (1.2 ± 1.7 min and periods of swimming at depths shallower than 5 m (0.25 ± 0.38 min. When the birds were on the ice, they primarily used time for resting (90.3 ± 4.1% of time and spent only 9.7 ± 4.1% of time traveling. Thus, it appears that, during foraging trips at sea, emperor penguins traveled during dives >5 m depth, and that sea ice was primarily used for resting. Sea ice probably provides refuge from natural predators such as leopard seals. We also suggest that 24 hours of sunlight and the cycling of dive bouts with short rest periods on sea ice allow emperor penguins to dive continuously throughout the day during foraging trips to sea.

  8. Modeling of plug-in electric vehicle travel patterns and charging load based on trip chain generation

    Science.gov (United States)

    Wang, Dai; Gao, Junyu; Li, Pan; Wang, Bin; Zhang, Cong; Saxena, Samveg

    2017-08-01

    Modeling PEV travel and charging behavior is the key to estimate the charging demand and further explore the potential of providing grid services. This paper presents a stochastic simulation methodology to generate itineraries and charging load profiles for a population of PEVs based on real-world vehicle driving data. In order to describe the sequence of daily travel activities, we use the trip chain model which contains the detailed information of each trip, namely start time, end time, trip distance, start location and end location. A trip chain generation method is developed based on the Naive Bayes model to generate a large number of trips which are temporally and spatially coupled. We apply the proposed methodology to investigate the multi-location charging loads in three different scenarios. Simulation results show that home charging can meet the energy demand of the majority of PEVs in an average condition. In addition, we calculate the lower bound of charging load peak on the premise of lowest charging cost. The results are instructive for the design and construction of charging facilities to avoid excessive infrastructure.

  9. TRIPs Agreement, Important Multilateral WTO Treaty

    Directory of Open Access Journals (Sweden)

    Oana-Maria Florescu

    2006-08-01

    Full Text Available This article aims at presenting the content and the frame of the TRIPs. Agreement. It starts by introducing the reader to the terms that defined the world economical climate by the time of the Agreement negociation. Also, it explains the need of having an Agreement on intellectual property rights with impact on the business world. Moreover, the article reviews the main provisions of the Agreement and the most important intellectual property rights.

  10. Assessment of FBR MONJU accident management reliability in causing reactor trips

    International Nuclear Information System (INIS)

    Sotsu, Masutake; Kurisaka, Kenichi

    2010-01-01

    This paper describes a method and application of quantitatively evaluating Accident Management (AM) reliability upon a reactor trip failure for the MONJU fast breeder reactor using a PSA technique. The present method comprises an allowable time estimation that is based on plant transient response analysis using the Super-COPD code that was developed for use in best estimates of the plant dynamics of MONJU and in estimating failure probability of operator's actions in AMs within the allowable time based on time records obtained from simulator training. Application of this method to MONJU resulted in the estimation that the allowable time for an unprotected loss-of-heat sink event would be more than the longest observed time of 326 s. The corresponding operation failure probability would be less than 0.1 even after taking the uncertainty into consideration. Combining this with a level 1 PSA revealed that the total frequency of core damage accompanying a reactor trip failure at MONJU could be decreased by at least 50 percent due to the reactor trip AM. (author)

  11. Sensitivity Analysis of Dousing Spray Trip on Radioactive Release in Pressure Tube Rupture Accident with Both End Fitting Failures

    Energy Technology Data Exchange (ETDEWEB)

    Jang, M. S.; Kang, H. S; Kim, S. R. [NESS, Daejeon (Korea, Republic of)

    2015-10-15

    We analyzed the sensitivity analysis of dousing spray trip conditions on radioactive release. In terms of conservativeness, the set 1 trip would be more appropriate in RR analysis than set 2 trip, which is the general condition of RR analysis. Radioactive releases from the containment building is related to containment air pressure, which increases by the coolant discharge from loss of coolant accident and the actuation conditions of dousing spray and so on. In LOCA analysis, the dousing spray trip conditions are set for the analysis objectives; for peak pressure (PP), for pressure signal (PS), for radioactive release (RR) and etc. In RR analysis, we would determine the dousing spray trip condition to increase radioactive release to the public for conservatism. Therefore, we carried out the sensitivity analysis of dousing spray trip condition on radioactive release from containment building using GOTHIC and SMART program for CANDU.

  12. Electric circuit breaker comprising a plurality of vacuum interrupters simultaneously operated by a common operator

    Science.gov (United States)

    Barkan, Philip; Imam, Imdad

    1980-01-01

    This circuit breaker comprises a plurality of a vacuum-type circuit interrupters, each having a movable contact rod. A common operating device for the interrupters comprises a linearly-movable operating member. The interrupters are mounted at one side of the operating member with their movable contact rods extending in a direction generally toward the operating member. Means is provided for mechanically coupling the operating member to the contact rods, and this means comprises a plurality of insulating operating rods, each connected at one end to the operating member and at its opposite end to one of the movable contact rods. The operating rods are of substantially equal length and have longitudinal axes that converge and intersect at substantially a common point.

  13. Identificación y fluctuación poblacional de especies de trips (Thysanoptera en aguacate 'hass' en Nayarit, México

    Directory of Open Access Journals (Sweden)

    M. A. Urías-López

    2007-01-01

    Full Text Available Este estudio se realizó del año 2004 al 2006 en La Yerba (Tepic y Emiliano Zapata (Xalisco Nayarit, México. Los objetivos fueron conocer las especies de trips de inflorescencias y hojas, la dinámica poblacional en follaje y la incidencia en el follaje de árboles tratados con diferentes niveles de fertilización. Los trips fueron de las familias: Aeolthripidae (tres especies, Phlaeothripidae (dos especies y Thripidae (una especie. Se registran por primera vez en aguacate para Nayarit los trips depredadores; Erythrothrips durango, Franklinothrips vespiformis y Leptothrips mcconelli, junto con Pseudophilothrips perseae (fitófago. En La Yerba, la población más alta del complejo de trips (2.09 trips·hoja-1 ocurrió en junio; en E. Zapata, ésta se registró en julio (4.10 trips·hoja-1. Las poblaciones más altas de trips ocurrieron durante periodos de floración y crecimiento vegetativo, y más bajas durante los meses de lluvia de verano. Las poblaciones de trips fueron 60 % más altas en E. Zapata que en La Yerba. No se detectó mayor población de trips en árboles con fertilización control, respecto a los de fertilización balanceada.

  14. Smooth criminal: convicted rule-breakers show reduced cognitive conflict during deliberate rule violations.

    Science.gov (United States)

    Jusyte, Aiste; Pfister, Roland; Mayer, Sarah V; Schwarz, Katharina A; Wirth, Robert; Kunde, Wilfried; Schönenberg, Michael

    2017-09-01

    Classic findings on conformity and obedience document a strong and automatic drive of human agents to follow any type of rule or social norm. At the same time, most individuals tend to violate rules on occasion, and such deliberate rule violations have recently been shown to yield cognitive conflict for the rule-breaker. These findings indicate persistent difficulty to suppress the rule representation, even though rule violations were studied in a controlled experimental setting with neither gains nor possible sanctions for violators. In the current study, we validate these findings by showing that convicted criminals, i.e., individuals with a history of habitual and severe forms of rule violations, can free themselves from such cognitive conflict in a similarly controlled laboratory task. These findings support an emerging view that aims at understanding rule violations from the perspective of the violating agent rather than from the perspective of outside observer.

  15. Field trip report: Observations made at Yucca Mountain, Nye County, Nevada. Special report No. 2

    International Nuclear Information System (INIS)

    Hill, C.A.

    1993-03-01

    A field trip was made to the Yucca Mountain area on December 5-9, 1992 by Jerry Frazier, Don Livingston, Christine Schluter, Russell Harmon, and Carol Hill. Forty-three separate stops were made and 275 lbs. of rocks were collected during the five days of the field trip. Key localities visited were the Bare Mountains, Yucca Mountain, Calico Hills, Busted Butte, Harper Valley, Red Cliff Gulch, Wahmonie Hills, Crater Flat, and Lathrop Wells Cone. This report only describes field observations made by Carol Hill. Drawings are used rather than photographs because cameras were not permitted on the Nevada Test Site during this trip

  16. American Samoa Longline Fishery Trip Expenditure (2006 to present)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a time-series dataset for trip expenditure data for the American Samoa-based longline fleet from August 2006 to present. The dataset includes 10 variable...

  17. Influence of deep cryogenic treatment on structure and wear resistance of materials of hydraulic breaker chisels

    Science.gov (United States)

    Bolobov, V. I.; BinhLe, Thanh

    2018-03-01

    It is shown that shallow cryogenic treatment at -75°C (SCT) of the materials of hydraulic breaker chisels - P20, 1080 and D2 steels leads to a decrease (44 ÷ 82%) in the amount of retained austenite and an increase (26 ÷ 99%) in the amount of carbides in the structure of hardened steel, which is accompanied by an increase in its hardness (1.4 ÷ 2.1%) and abrasive wear resistance (10 ÷ 31%) with a simultaneous decrease in impact toughness (19 ÷ 24%). Deep cryogenic treatment at -196°C (DCT) and subsequent low-temperature tempering of D2 steel leads to a significant increase in its wear resistance (98%) and impact toughness (32%).

  18. Your private trips with Carlson Wagonlit Travel

    CERN Multimedia

    Carlson Wagonlit Travel

    2015-01-01

    Your Carlson Wagonlit Travel agency at CERN (building 62) also organizes private trips!     Do not hesitate to contact the “Tourism” team, at your disposal from Monday to Friday from 8:30 a.m. to 4:30 p.m. Phone: 72763. E-mail: cern@carlsonwagonlit.ch. Since 1 January 2015, everyone working at CERN benefits from lower booking fees.

  19. Pre- and post-test analyses of a KKL turbine trip test at 109% power using RETRAN-3D

    Energy Technology Data Exchange (ETDEWEB)

    Coddington, P

    2001-03-01

    As part of the PSI/HSK STARS project, pre-test calculations have been performed for a KKL turbine trip test at 109% power using the RETRAN-3D code. In this paper, we first present the results of these calculations, together with a description of the test and a comparison of the results with the measured plant data, and then discuss in more detail the differences between the pre-test results and the plant measurements, including the differences in the initial and boundary conditions, and how these differences influenced the calculated results. Finally, we comment on a series of post-test and sensitivity analyses, which were performed to resolve some of the discrepancies. The results of the pre-test (blind) calculations show good overall agreement with the experimental data, particularly for the maximum in the steam-line mass flow rate following the opening of the turbine bypass valves. This is of critical importance, since the steam-line flow has the least margin to the reactor scram limit. The agreement is especially good since the control rod banks used for the selected rod insertion were changed from those given in the test specification. Following a review of the comparison of the pre-test calculations with the measured data, several deficiencies in the RETRAN-3D model for KKL were identified and corrected as part of the post-test analysis. This allowed for both an improvement in the calculated results, and a deeper understanding of the behaviour of the turbine trip transient. (author)

  20. Pre- and post-test analyses of a KKL turbine trip test at 109% power using RETRAN-3D

    International Nuclear Information System (INIS)

    Coddington, P.

    2001-01-01

    As part of the PSI/HSK STARS project, pre-test calculations have been performed for a KKL turbine trip test at 109% power using the RETRAN-3D code. In this paper, we first present the results of these calculations, together with a description of the test and a comparison of the results with the measured plant data, and then discuss in more detail the differences between the pre-test results and the plant measurements, including the differences in the initial and boundary conditions, and how these differences influenced the calculated results. Finally, we comment on a series of post-test and sensitivity analyses, which were performed to resolve some of the discrepancies. The results of the pre-test (blind) calculations show good overall agreement with the experimental data, particularly for the maximum in the steam-line mass flow rate following the opening of the turbine bypass valves. This is of critical importance, since the steam-line flow has the least margin to the reactor scram limit. The agreement is especially good since the control rod banks used for the selected rod insertion were changed from those given in the test specification. Following a review of the comparison of the pre-test calculations with the measured data, several deficiencies in the RETRAN-3D model for KKL were identified and corrected as part of the post-test analysis. This allowed for both an improvement in the calculated results, and a deeper understanding of the behaviour of the turbine trip transient. (author)

  1. 75 FR 59154 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Trip Limit...

    Science.gov (United States)

    2010-09-27

    ... (453.6 kg) per trip, Georges Bank (GB) yellowtail flounder to 100 lb (45.4 kg) per trip, and white hake... the U.S./Canada Management Area to include the entire Western U.S./Canada Area; and authorizes the use of the rope separator trawl in the Western U.S./Canada Area for NE multispecies vessels fishing in...

  2. Deklarasi Doha dalam Perspektif Akses Obat Murah dan Terjangkau: sebuah Pelengkap Perjanjian TRIPS

    OpenAIRE

    Utomo, Tomi Suryo

    2007-01-01

    The Doha Declaration was developed after protests from developing and least developed countries asserting the TRIPS safeguards were unclear and ambiguous. Developing countries and least developed countries sought an interpretive tool for the TRIPS safeguards which fulfills the requirements of International law, in particular the Vienna Convention on the Law of Treaties and the legislative process of negotiation under the WTO decision making framework. Through the Doha Declaration, developing ...

  3. Multilateral Organization vs. Bilateral Negotiations: A Case of the Trade-Related Aspects of Intellectual Property Rights (TRIPs

    Directory of Open Access Journals (Sweden)

    Namhoon Kwon

    2001-12-01

    Full Text Available In the 1990s, the issue of intellectual property rights (IPR protection gained a prominent place on the international trade agenda, which led to the establishment of the trade-related aspects of intellectual property rights (TRIPs as a part of the WTO regime. Two questions are asked regarding this development: whether a multilateral organization such as the WTO performs better than bilateral negotiations in resolving IPR disputes, and what happened around the 1990s to create an environment favorable to the establishment of a multilateral organization. To deal with these issues, this paper takes the IPE (international political economy approach. Using a very simple game theory model, I derive the cases in which a multilateral organization has better performances. Then, it is used to show that political pressures due to the growth of the US trade deficit in the late 1980s could have been the reason that a multilateral organization became the institutional equilibrium.

  4. Harvesting Collective Trend Observations from Large Scale Study Trips

    DEFF Research Database (Denmark)

    Eriksen, Kaare; Ovesen, Nis

    2014-01-01

    To enhance industrial design students’ decoding and understanding of the technological possibilities and the diversity of needs and preferences in different cultures it is not unusual to arrange study trips where such students acquire a broader view to strengthen their professional skills and app...... numbers of students to the annual Milan Design Week and the Milan fair ‘I Saloni’ in Italy. The present paper describes and evaluates the method, the theory behind it, the practical execution of the trend registration, the results from the activities and future perspectives....... and approach, hence linking the design education and the design culture of the surrounding world. To improve the professional learning it is useful, though, to facilitate and organize the trips in a way that involves systematic data collection and reporting. This paper presents a method for facilitating study...

  5. Multiagents-based wide area protection with best-effort adaptive strategy

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yongli; Wang, Dewen [North China Electric Power University, Baoding (China); Song, Shaoqun [Fuzhou Electric Power Industry Bureau, Fujian Province (China)

    2009-02-15

    Abstract - Multi-trips of circuit breakers often occur within a short period in a severe blackout, and the tripping usually relates to relays' mal-operations. In fact, when two ore more electric primary devices are isolated by circuit breakers, the settings of most relays to protect their power system are getting infeasible and uncoordinated. Adaptive settings are needed to prevent them from wrong operation. This paper presents an adaptive protection scheme based on wide area information with best-effort protection strategy, and the outline of multiagents and WAN Based Adaptive Protection System (MAWAPS). In the scheme, the best-effort adaptive strategy is used to guarantee the adaptive settings to operate safely and effectively in most situations. The IP/SDH-based wide area network (WAN) is used to realize real-time wide area information exchange in the proposed protection scheme. Adaptive setting algorithms for the second stage zero-sequence current and phase overcurrent relays are proposed, which can provide larger line coverage than traditional relays. Moreover, multiagent techniques and IEC 61850 are employed to realize the fast communication between different agents, and MMS plays a prominent role in real-time remote communication. A simulating system has been developed according to the above ideas and approaches, and the experimental results show that the proposed adaptive protection scheme is feasible from the view of protective performance including the executing time. (author)

  6. Boundary Layer Transition and Trip Effectiveness on an Apollo Capsule in the JAXA High Enthalpy Shock Tunnel (HIEST) Facility

    Science.gov (United States)

    Kirk, Lindsay C.; Lillard, Randolph P.; Olejniczak, Joseph; Tanno, Hideyuki

    2015-01-01

    Computational assessments were performed to size boundary layer trips for a scaled Apollo capsule model in the High Enthalpy Shock Tunnel (HIEST) facility at the JAXA Kakuda Space Center in Japan. For stagnation conditions between 2 MJ/kg and 20 MJ/kg and between 10 MPa and 60 MPa, the appropriate trips were determined to be between 0.2 mm and 1.3 mm high, which provided kappa/delta values on the heatshield from 0.15 to 2.25. The tripped configuration consisted of an insert with a series of diamond shaped trips along the heatshield downstream of the stagnation point. Surface heat flux measurements were obtained on a capsule with a 250 mm diameter, 6.4% scale model, and pressure measurements were taken at axial stations along the nozzle walls. At low enthalpy conditions, the computational predictions agree favorably to the test data along the heatshield centerline. However, agreement becomes less favorable as the enthalpy increases conditions. The measured surface heat flux on the heatshield from the HIEST facility was under-predicted by the computations in these cases. Both smooth and tripped configurations were tested for comparison, and a post-test computational analysis showed that kappa/delta values based on the as-measured stagnation conditions ranged between 0.5 and 1.2. Tripped configurations for both 0.6 mm and 0.8 mm trip heights were able to effectively trip the flow to fully turbulent for a range of freestream conditions.

  7. WIPP site and vicinity geological field trip. A report of a field trip to the proposed Waste Isolation Pilot Plant project in Southeastern New Mexico, June 16 to 18, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Chaturvedi, L

    1980-10-01

    The Environmental Evaluation Group is conducting an assessment of the radiological health risks to people from the Waste Isolation Pilot Plant. As a part of this work, EEG is making an effort to improve the understanding of those geological issues concerning the WIPP site which may affect the radiological consequences of the proposed repository. One of the important geological issues to be resolved is the timing and the nature of the dissolution processes which may have affected the WIPP site. EEG organized a two-day conference of geological scientists, on January 17-18, 1980. On the basis of the January conference and the June field trip, EEG has formed the following conclusions: (1) it has not been clearly established that the site or the surrounding area has been attacked by deep dissolution to render it unsuitable for the nuclear waste pilot repository; (2) the existence of an isolated breccia pipe at the site unaccompanied by a deep dissolution wedge, is a very remote possibility; (3) more specific information about the origin and the nature of the brine reservoirs is needed. An important question that should be resolved is whether each encounter with artesian brine represents a separate pocket or whether these occurrences are interconnected; (4) Anderson has postulated a major tectonic fault or a fracture system at the Basin margin along the San Simon Swale; (5) the area in the northern part of the WIPP site, identified from geophysical and bore hole data as the disturbed zone, should be further investigated to cleary understand the nature and significance of this structural anomaly; and (6) a major drawback encountered during the discussions of geological issues related to the WIPP site is the absence of published material that brings together all the known information related to a particular issue.

  8. Transport Risk Index of Physiologic Stability, version II (TRIPS-II): a simple and practical neonatal illness severity score.

    Science.gov (United States)

    Lee, Shoo K; Aziz, Khalid; Dunn, Michael; Clarke, Maxine; Kovacs, Lajos; Ojah, Cecil; Ye, Xiang Y

    2013-05-01

    Derive and validate a practical assessment of infant illness severity at admission to neonatal intensive care units (NICUs). Prospective study involving 17,075 infants admitted to 15 NICUs in 2006 to 2008. Logistic regression was used to derive a prediction model for mortality comprising four empirically weighted items (temperature, blood pressure, respiratory status, response to noxious stimuli). This Transport Risk Index of Physiologic Stability, version II (TRIPS-II) was then validated for prediction of 7-day and total NICU mortality. TRIPS-II discriminated 7-day (receiver operating curve [ROC] area, 0.90) and total NICU mortality (ROC area, 0.87) from survival. Furthermore, there was a direct association between changes in TRIPS-II at 12 and 24 hours and mortality. There was good calibration across the full range of TRIPS-II scores and the gestational age at birth, and addition of TRIPS-II improved performance of prediction models that use gestational age and baseline population risk variables. TRIPS-II is a validated benchmarking tool for assessing infant illness severity at admission and for up to 24 hours after. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  9. Collaborative Research: Bringing Problem Solving in the Field into the Classroom: Developing and Assessing Virtual Field Trips for Teaching Sedimentary and Introductory Geology

    Science.gov (United States)

    Wang, P.; Caldwell, M.

    2012-12-01

    Coastal Florida offers a unique setting for the facilitation of learning about a variety of modern sedimentary environments. Despite the conflicting concept of "virtual" and "actual" field trip, and the uncertainties associated with the implementation and effectiveness, virtual trips provide likely the only way to reach a large diversified student population and eliminate travel time and expenses. In addition, with rapidly improving web and visualization technology, field trips can be simulated virtually. It is therefore essential to systematically develop and assess the educational effectiveness of virtual field trips. This project is developing, implementing, and assessing a series of virtual field trips for teaching undergraduate sedimentary geology at a large four-year research university and introductory geology at a large two-year community college. The virtual field trip is based on a four-day actual field trip for a senior level sedimentary geology class. Two versions of the virtual field trip, one for advanced class and one for introductory class, are being produced. The educational outcome of the virtual field trip will be compared to that from actual field trip. This presentation summarizes Year 1 achievements of the three-year project. The filming, editing, and initial production of the virtual field trip have been completed. Formative assessments were conducted by the Coalition for Science Literacy at the University of South Florida. Once tested and refined, the virtual field trips will be disseminated through broadly used web portals and workshops at regional and national meetings.

  10. 41 CFR 302-5.8 - How many househunting trips may my agency authorize in connection with a particular transfer?

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false How many househunting trips may my agency authorize in connection with a particular transfer? 302-5.8 Section 302-5.8 Public... EXPENSES Employee's Allowance For Househunting Trip Expenses § 302-5.8 How many househunting trips may my...

  11. Londonfahrten mit Hauptschuelern--ein Erfahrungsbericht (Trips to London with Junior High School Students--Experience Report)

    Science.gov (United States)

    Schepp, Peter

    1975-01-01

    Discusses trips to London with junior high school students: planning, choice of goals, costs, pocket money, board and lodging, language preparation, programming. Gives a detailed account of a trip which was particularly geared to the students' circumstances. The possibility of partnership with English schools is discussed. (Text is in German.)…

  12. Gravel packing dual zones in one trip reduces offshore completion time

    International Nuclear Information System (INIS)

    Brannon, D.H.; Harrison, D.T.; van Sickle, E.W.

    1991-01-01

    A single trip, dual-zone gravel pack system was used to successfully gravel pack two wells on Green Canyon platform 52 A in the Gulf of Mexico. An average 56 hours was saved on each well, representing reductions of about 25% in completion time and 26% in completion cost per well. Time-sensitive costs had the largest impact on Green Canyon 52 A final well completion cost; therefore, new technology or more efficient operations were required to minimize completion time. One way to enhance project economics was to gravel pack two separate zones in one trip. In this paper, four objectives are addressed during development of a single trip tool to gravel pack the stacked zones of the Marquette project. These were time and cost reduction, removal of loss circulation material (LCM) prior to gravel packing, zone isolation during gravel packing and use of conventional gravel placement techniques. The design requirement that all LCM (salt and/or viscous polymer pills), perforation debris and formation sand be removed from the wellbore prior to gravel packing was accomplished by incorporating a washdown feature that allows circulation at the bottom of the gravel pack assembly prior to landing in the sump packer

  13. Phase transformation and local mechanical properties of TRIP steel in a simulated and real resistance spot weld process; Phasenumwandlung und lokale mechanische Eigenschaften von TRIP Stahl beim simulierten und realen Widerstandspunktschweissprozess

    Energy Technology Data Exchange (ETDEWEB)

    Brauser, Stephan

    2013-06-01

    TRIP steels give high strength along with good ductility owing to metastable austenite to martensite phase transformation (TRIP effect) caused by mechanical load. Under the extreme process-specific heating and cooling rates of resistance spot welding, these materials may undergo modifications in their austenite portion resulting in changed mechano- technological performance locally. The prime objective of this study was therefore to carry out microstructure analyses of the spot weld area in order to identify the modified portion of austenite and the resulting changes in local mechanical performance with special consideration of the TRIP effect. First, the metastable austenite portion in the unprocessed parent metal was quantified by in-situ diffraction using high energy synchrotron radiation. Next, the basic aspects of temperature dependent austenite transformation in the heating and cooling process were investigated in furnace experiments under defined temperature profiles. Continuative Gleeble tests and furnace experiments were conducted using various temperature profiles with different peaks occurring locally in the spot welding process in order to enable systematic assessment of the influence of temperature and of heating and cooling conditions on the austenite content under real conditions. Correlation experiments between the mechanical characteristics of thermally prepared tensile specimens and the metallographically and roentgenographically determined austenite contents allowed it to ascertain the metastable, i.e. transformable austenite portions. Finally, the results were evaluated concerning their transferability to real resistance spot welds. It was demonstrated that the austenite to martensite phase transformation can come into action only in a strongly localized material area in the transition zone between heat-affected zone and base metal. Consequently, the TRIP effect does not significantly affect the strength and ductility performance in the joining

  14. Development of field programmable gate array-based reactor trip functions using systems engineering approach

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jae Cheon; Ahmed, Ibrahim [Nuclear Power Plant Engineering, KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2016-08-15

    Design engineering process for field programmable gate array (FPGA)-based reactor trip functions are developed in this work. The process discussed in this work is based on the systems engineering approach. The overall design process is effectively implemented by combining with design and implementation processes. It transforms its overall development process from traditional V-model to Y-model. This approach gives the benefit of concurrent engineering of design work with software implementation. As a result, it reduces development time and effort. The design engineering process consisted of five activities, which are performed and discussed: needs/systems analysis; requirement analysis; functional analysis; design synthesis; and design verification and validation. Those activities are used to develop FPGA-based reactor bistable trip functions that trigger reactor trip when the process input value exceeds the setpoint. To implement design synthesis effectively, a model-based design technique is implied. The finite-state machine with data path structural modeling technique together with very high speed integrated circuit hardware description language and the Aldec Active-HDL tool are used to design, model, and verify the reactor bistable trip functions for nuclear power plants.

  15. A robust and high-performance queue management controller for large round trip time networks

    Science.gov (United States)

    Khoshnevisan, Ladan; Salmasi, Farzad R.

    2016-05-01

    Congestion management for transmission control protocol is of utmost importance to prevent packet loss within a network. This necessitates strategies for active queue management. The most applied active queue management strategies have their inherent disadvantages which lead to suboptimal performance and even instability in the case of large round trip time and/or external disturbance. This paper presents an internal model control robust queue management scheme with two degrees of freedom in order to restrict the undesired effects of large and small round trip time and parameter variations in the queue management. Conventional approaches such as proportional integral and random early detection procedures lead to unstable behaviour due to large delay. Moreover, internal model control-Smith scheme suffers from large oscillations due to the large round trip time. On the other hand, other schemes such as internal model control-proportional integral and derivative show excessive sluggish performance for small round trip time values. To overcome these shortcomings, we introduce a system entailing two individual controllers for queue management and disturbance rejection, simultaneously. Simulation results based on Matlab/Simulink and also Network Simulator 2 (NS2) demonstrate the effectiveness of the procedure and verify the analytical approach.

  16. Full Random Coefficients Multilevel Modeling of the Relationship between Land Use and Trip Time on Weekdays and Weekends

    Directory of Open Access Journals (Sweden)

    Tae-Hyoung Tommy Gim

    2017-10-01

    Full Text Available Interests in weekend trips are increasing, but few have studied how they are affected by land use. In this study, we analyze the relationship between compact land use characteristics and trip time in Seoul, Korea by comparing two research models, each of which uses the weekday and weekend data of the same travelers. To secure sufficient numbers of subjects and groups, full random coefficients multilevel models define the trip as level one and the neighborhood as level two, and find that level-two land use characteristics account for less variation in trip time than level-one individual characteristics. At level one, weekday trip time is found to be reduced by the choice of the automobile as a travel mode, but not by its ownership per se. In addition, it becomes reduced if made by high income travelers and extended to travel to quality jobs. Among four land use characteristics at level two, population density, road connectivity, and subway availability are shown to be significant in the weekday model. Only subway availability has a positive relationship with trip time and this finding is consistent with the level-one result that the choice of automobile alternatives increases trip time. The other land use characteristic, land use balance, turns out to be a single significant land use variable in the weekend model, implying that it is concerned mainly with non-work, non-mandatory travel.

  17. Swirling flow and its influence on dc arcs in a duo-flow hybrid circuit breaker

    International Nuclear Information System (INIS)

    Kweon, K Y; Lee, H S; Yan, J D; Fang, M T C; Park, K Y

    2009-01-01

    The effects of swirling flow on the behaviour of dc SF 6 arcs in a duo-flow nozzle are computationally investigated in the electric current range 3-7 kA. A swirling flow is produced by the interaction of the magnetic field of a current-carrying coil and the plasma. Results show that a strong swirling flow is generated in regions where a large radial current density exists as a result of the conducting arc column rapidly changing its radial dimension. The presence of the swirling flow reduces the axis pressure, modifies the arc shape and slightly lowers the arc voltage (2-5%) in comparison with the case without considering the swirling flow. The different natures of swirling flows in a plasma jet/arc heater and in a hybrid circuit breaker are also discussed.

  18. A Day at the Museum: The Impact of Field Trips on Middle School Science Achievement

    Science.gov (United States)

    Whitesell, Emilyn Ruble

    2016-01-01

    Field trips are an important feature of the United States' education system, although in the current context of high-stakes tests and school accountability, many schools are shifting resources away from enrichment. It is critical to understand how field trips and other informal learning experiences contribute to student test scores, but little…

  19. Use of loop-seals for the control of the overpressures in hydraulic transients evolving in a sea service water system

    Energy Technology Data Exchange (ETDEWEB)

    Canetta, D.; Capozza, A.; Iovino, G.

    1985-01-01

    The transient response following pump trip-offs and start-ups was investigated in the sea water system of a nuclear power plant. Specific care was devoted to water column separation and cavity collapse phenomena. A computer program designed for analysis of complex hydraulic networks was used. It is found that dangerous overpressures can be avoided by the use of loop seals. The design of the vacuum breaker valves of the loop seals and the optimization of overall transient behavior is discussed. 1 reference.

  20. Task types and error types involved in the human-related unplanned reactor trip events

    International Nuclear Information System (INIS)

    Kim, Jae Whan; Park, Jin Kyun

    2008-01-01

    In this paper, the contribution of task types and error types involved in the human-related unplanned reactor trip events that have occurred between 1986 and 2006 in Korean nuclear power plants are analysed in order to establish a strategy for reducing the human-related unplanned reactor trips. Classification systems for the task types, error modes, and cognitive functions are developed or adopted from the currently available taxonomies, and the relevant information is extracted from the event reports or judged on the basis of an event description. According to the analyses from this study, the contributions of the task types are as follows: corrective maintenance (25.7%), planned maintenance (22.8%), planned operation (19.8%), periodic preventive maintenance (14.9%), response to a transient (9.9%), and design/manufacturing/installation (6.9%). According to the analysis of the error modes, error modes such as control failure (22.2%), wrong object (18.5%), omission (14.8%), wrong action (11.1%), and inadequate (8.3%) take up about 75% of the total unplanned trip events. The analysis of the cognitive functions involved in the events indicated that the planning function had the highest contribution (46.7%) to the human actions leading to unplanned reactor trips. This analysis concludes that in order to significantly reduce human-induced or human-related unplanned reactor trips, an aide system (in support of maintenance personnel) for evaluating possible (negative) impacts of planned actions or erroneous actions as well as an appropriate human error prediction technique, should be developed

  1. Task types and error types involved in the human-related unplanned reactor trip events

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Whan; Park, Jin Kyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-12-15

    In this paper, the contribution of task types and error types involved in the human-related unplanned reactor trip events that have occurred between 1986 and 2006 in Korean nuclear power plants are analysed in order to establish a strategy for reducing the human-related unplanned reactor trips. Classification systems for the task types, error modes, and cognitive functions are developed or adopted from the currently available taxonomies, and the relevant information is extracted from the event reports or judged on the basis of an event description. According to the analyses from this study, the contributions of the task types are as follows: corrective maintenance (25.7%), planned maintenance (22.8%), planned operation (19.8%), periodic preventive maintenance (14.9%), response to a transient (9.9%), and design/manufacturing/installation (6.9%). According to the analysis of the error modes, error modes such as control failure (22.2%), wrong object (18.5%), omission (14.8%), wrong action (11.1%), and inadequate (8.3%) take up about 75% of the total unplanned trip events. The analysis of the cognitive functions involved in the events indicated that the planning function had the highest contribution (46.7%) to the human actions leading to unplanned reactor trips. This analysis concludes that in order to significantly reduce human-induced or human-related unplanned reactor trips, an aide system (in support of maintenance personnel) for evaluating possible (negative) impacts of planned actions or erroneous actions as well as an appropriate human error prediction technique, should be developed.

  2. DISPAQ: Distributed Profitable-Area Query from Big Taxi Trip Data.

    Science.gov (United States)

    Putri, Fadhilah Kurnia; Song, Giltae; Kwon, Joonho; Rao, Praveen

    2017-09-25

    One of the crucial problems for taxi drivers is to efficiently locate passengers in order to increase profits. The rapid advancement and ubiquitous penetration of Internet of Things (IoT) technology into transportation industries enables us to provide taxi drivers with locations that have more potential passengers (more profitable areas) by analyzing and querying taxi trip data. In this paper, we propose a query processing system, called Distributed Profitable-Area Query ( DISPAQ ) which efficiently identifies profitable areas by exploiting the Apache Software Foundation's Spark framework and a MongoDB database. DISPAQ first maintains a profitable-area query index (PQ-index) by extracting area summaries and route summaries from raw taxi trip data. It then identifies candidate profitable areas by searching the PQ-index during query processing. Then, it exploits a Z-Skyline algorithm, which is an extension of skyline processing with a Z-order space filling curve, to quickly refine the candidate profitable areas. To improve the performance of distributed query processing, we also propose local Z-Skyline optimization, which reduces the number of dominant tests by distributing killer profitable areas to each cluster node. Through extensive evaluation with real datasets, we demonstrate that our DISPAQ system provides a scalable and efficient solution for processing profitable-area queries from huge amounts of big taxi trip data.

  3. Reducing scram frequency by modifying/eliminating steam generator low-low level reactor trip setpoint for Maanshan nuclear power plant

    International Nuclear Information System (INIS)

    Yuann, R.Y.; Chiang, S.C.; Hsiue, J.K.; Chen, P.C.

    1987-01-01

    The feasibility of modification/elimination of steam generator low-low level reactor trip setpoint is evaluated by using RETRAN-02 code for the purpose of reducing scram frequency in Maanshan 3-loop pressurized water reactor. The ANS Condition II event loss of normal feedwater and condition IV event feedwater system line break are the basis for steam generator low-low level reactor trip setpoint sensitivity analysis, including various initial reactor power levels, reactivity feedback coefficients, and system functions assumptions etc., have been performed for the two basis events with steam generator low-low level reactor trip setpoint at 0% narrow range and without this trip respectively. The feasibility of modifying/eliminating current steam generator low-low level reactor trip setpoint is then determined based on whether the analysis results meet with the ANS Condition II and IV acceptance criteria or not

  4. Multi-modal trip planning system : Northeastern Illinois Regional Transportation Authority.

    Science.gov (United States)

    2013-01-01

    This report evaluates the Multi-Modal Trip Planner System (MMTPS) implemented by the Northeastern Illinois Regional Transportation Authority (RTA) against the specific functional objectives enumerated by the Federal Transit Administration (FTA) in it...

  5. Astronaut Neil Armstrong studies rock samples during geological field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, studies rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  6. Microprocessor-based, on-line decision aid for resolving conflicting nuclear reactor instrumentation

    International Nuclear Information System (INIS)

    Alesso, H.P.

    1981-01-01

    We describe one design for a microprocessor-based, on-line decision aid for identifying and resolving false, conflicting, or misleading instrument indications resulting from certain systems interactions for a pressurized water reactor. The system processes sensor signals from groups of instruments that track together under nominal transient and certain accident conditions, and alarms when they do not track together. We examine multiple-casualty systems interaction and formulate a trial grouping of variables that track together under specified conditions. A two-of-three type redundancy check of key variables provides alarm and indication of conflicting information when one signal suddenly tracks in opposition due to multiple casualty, instrument failure, and/or locally abnormal conditions. Since a vote count of two of three variables in conflict as inconclusive evidence, the system is not designed to provide tripping or corrective action, but improves the operator/instrument interface by providing additional and partially digested information

  7. Current Practices for Providing School Field Trip Meals: Perspectives of School Nutrition Managers and Teachers

    Science.gov (United States)

    Sneed, Jeannie; Vaterlaus Patten, Emily

    2015-01-01

    Purpose/Objectives: The Healthy, Hunger Free Kids Act of 2010 extended the requirements for a school food safety program to wherever food is stored, prepared, or served, including meals for field trips. The purpose of this study was to determine what foods are used for field trip meals, how those foods are transported and stored, and what standard…

  8. Sense of place in outdoor-pursuits trip groups

    Science.gov (United States)

    Sharon L. Todd; Anderson B. Young; Lynn S. Anderson; Timothy S. O' Connell; Mary Breunig

    2009-01-01

    Studies have revealed that sense of community and group cohesion increase significantly over time in outdoor-pursuits trip groups. This study sought to understand similar development of sense of place. Do people simultaneously become more attached to or dependent on the natural environment as they grow closer to each other? Results from a study of college students...

  9. Feasibility of a continuous surface mining machine using impact breakers. First quarterly report, October 1-December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, A. T.

    1980-01-01

    This is the first quarterly report on the efforts to evaluate the feasibility of excavating coal and overburden from surface mines using impact breakers. The initial stages of the project are devoted to a literature search, equipment selection, test site selection, and conceptual test system design. Hence, this report details the progress made in these areas; the next quarter will see the finalization of Phase I. Included as appendices to this report are FMA internal reports on the individual mines visited. These reports are the basis of the test site selection, and have been censored here to remove data the mine operators deemed as confidential.

  10. Senior travelers' trip chaining behavior : survey results and data analysis.

    Science.gov (United States)

    2011-08-01

    The research team conducted a survey of travel and activity scheduling behavior to better understand senior : citizens trip chaining behavior in the Chicago metropolitan areas most populous counties. The team used an : internet-based, prompted ...

  11. Development, Dedication and Application of an Automatic Seismic Trip System for Nuclear Power Plants of Taiwan Power Company

    International Nuclear Information System (INIS)

    Liao, Hsin-kai; Lee, Chung-lin; Chen, Chang-kuo; Hsu, Yao-tung; Shyu, Shian-shing

    2011-01-01

    This paper describes the setups of Automatic Seismic Trip System (ASTS), including development, dedication and implementation, for Nuclear Power Plants (NPPs) of Taiwan Power Company (TPC). The purposed ASTS was designed to trip the reactor when big earthquake occurs. These ASTS were classified as class 1E equipment. They were developed and dedicated for safety applications in accordance with IEEE 323-1983, IEEE 344-1987, IEEE 383-1974 and Reg. Guide 1.180 R1. In order to meet the technical specification required by TPC, three sub-units in the ASTS were developed: Earthquake sensors: Kinemetrices FBA-23 triaxial accelerometers are selected since they were successfully used in Taiwan for seismic monitoring for more than 10 years. Signal conditioning module: It is designed to reduce noise from motion accelerometer (FBA-23) and then transmit seismic signal to the set-point and trip unit via instrument amplify circuit, 0.1 to 10Hz band pass filter circuit, absolute-value converter and voltage to current converter. Trip control module: after comparing the seismic signal level and set-point, the result will decide whether to drive the output relay or not. The output relay is used as the interface between ASTS and the reactor protection system in NPP. For the commercial grade item dedication for safety application, five processes were conducted. Those processes are Seismic test: to use plant specific required response spectrum (RRS), the test required spectrum should envelop RRS: Seismic auto-trip accuracy test: must not trip when filtered PA below set point minus 0.05g, and must trip when filtered PA exceeds set point over 0.05g. Trip signals occurred within 10 second interval are considered as same events: NEMA4 water proof test for sensor box: Anti-radiation test: 8.76x100 rads over 40 years: EMI/EMC test: follow RG 1.180 requirement. The ASTS were installed in three NPPs, six units in total, without connection to RPS in 2006. After one year reliable operation, the

  12. Slip, trip and fall accidents occurring during the delivery of mail.

    Science.gov (United States)

    Bentley, T A; Haslam, R A

    1998-12-01

    This study sought to identify causal factors for slip, trip and fall accidents occurring during the delivery of mail. Analysis of in-house data produced information about accident circumstances for 1734 fall cases. The most common initiating events in delivery falls were slips and trips. Slips most often occurred on snow, ice or grass, while trips tended to involve uneven pavements, obstacles and kerbs. Nearly one-fifth of falls occurred on steps, with step falls requiring longer absence from work than falls on the level. Half of all falls occurred during November-February and three-quarters of falls occurred between 7 and 9 a.m. Incidence rates for female employees were 50% higher than for their male colleagues. Accident-independent methods included interviews with safety personnel and managers, discussion groups with delivery employees, and a questionnaire survey of employees and managers. These techniques provided data on risk factors related to the task, behaviour, footwear and equipment. Arising from these accident-independent investigations, it is suggested that unsafe working practices, such as reading addresses while walking and taking shortcuts, increase the risk of falls. Organizational issues include management safety activities, training and equipment provision. Measures are discussed that might lead to a reduction in the incidence of delivery fall accidents.

  13. Detailed analysis of the ANO-2 turbine trip test

    International Nuclear Information System (INIS)

    McDonald, T.A.; Tessier, J.H.; Senda, Y.; Waterman, M.D.

    1983-01-01

    A RELAP5/MOD1 (Cycle 18) computer code simulation of the ANO-2 turbine trip test from 98% power level was performed for use in vendor code qualification studies. Results focused on potential improvements to simulation capabilities and plant data acquisition systems to provide meaningful comparisons between the calculations and the test data. The turbine trip test was selected because it resulted in an unplanned sequence of events that broadly affected the plant process systems and their controls. The pressurizer spray valve stuck open at an undetermined flow area, and an atmospheric dump valve remained stuck fully open while several atmospheric dump and secondary side safety valves were unavailable throughout. Thus, although the plant remained always in a safe condition, this transient potentially provided an unusual set of data against which the fidelity of a NSSS simulation by RELAP5/MOD1 along with certain vendor analysis codes might be judged

  14. Investigation of the Formability of TRIP780 Steel Sheets

    Science.gov (United States)

    Song, Yang

    The formability of a metal sheet is dependent on its work hardening behaviour and its forming limits; and both aspects must be carefully determined in order to accurately simulate a particular forming process. This research aims to characterize the formability of a TRIP780 sheet steel using advanced experimental testing and analysis techniques. A series of flat rolling and tensile tests, as well as shear tests were conducted to determine the large deformation work hardening behaviour of this TRIP780 steel. Nakazima tests were carried out up to fracture to determine the forming limits of this sheet material. A highly-automated method for generating a robust FLC for sheet materials from DIC strain measurements was created with the help of finite element simulations, and evaluated against the conventional method. A correction algorithm that aims to compensate for the process dependent effects in the Nakazima test was implemented and tested with some success.

  15. Effective Lesson Planning: Field Trips in the Science Curriculum

    Science.gov (United States)

    Rieger, C. R.

    2010-10-01

    Science field trips can positively impact and motivate students. However, if a field trip is not executed properly, with appropriate preparation and follow-up reinforcement, it can result in a loss of valuable educational time and promote misconceptions in the students. This study was undertaken to determine if a classroom lesson before an out-of-the-classroom activity would affect learner gain more or less than a lesson after the activity. The study was based on the immersive theater movie ``Earth's Wild Ride'' coupled with a teacher-led Power Point lesson. The participants in the study were students in a sixth grade physical science class. The order of lessons showed no detectable effect on final learner outcomes. Based on pre- and post-testing, improvement in mean learning gain came from the teacher-led lesson independent of the movie. The visit to the immersive theater, however, had significant positive effects that did not show up in the quantitative results of the testing.

  16. Field trip method as an effort to reveal student environmental literacy on biodiversity issue and context

    Science.gov (United States)

    Rijal, M.; Saefudin; Amprasto

    2018-05-01

    Field trip method through investigation of local biodiversity cases can give educational experiences for students. This learning activity was efforts to reveal students environmental literacy on biodiversity. The aim of study were (1) to describe the activities of students get information about the biodiversity issue and its context through field trip, (2) to describe the students findings during field trip, and (3) to reveal students environmental literacy based on pre test and post test. The research method used weak-experiment and involved 34 participants at senior high school students in Bandung-Indonesia. The research instruments for collecting data were environmental literacy test, observation sheets and questionnaire sheets for students. The analysis of data was quantitative descriptive. The results show that more than 79% of the students gave positive view for each field trip activity, i.e students activity during work (97%-100%); students activity during gather information (79%- 100%); students activity during exchange information with friend (82%-100%); and students interested to Biodiversity after field trip activity (85%-100%). Students gain knowledge about the diversity of animal vertebrate and its characteristics, the status and condition of animals, and the source of animal with the cases of animal diversity. The students environmental literacy tends to be moderate level based on test. Meanwhile, the average of the attitudes and action greater than the components of knowledge and cognitive skills.

  17. Analysis of Freight Trip Generation Model for Food and Beverage in Belo Horizonte (Brazil

    Directory of Open Access Journals (Sweden)

    Leise Kelli de Oliveira

    2017-01-01

    Full Text Available Today, one of the main challenges faced in urban logistics is the distribution of goods. In Brazil, mid to large cities have experienced consequences of unplanned urban sprawl and lack of adequate transportation infrastructure. The relationship between urban planning and transport stands out the attractiveness of some urban activities with direct impacts on the movement of people and goods and other component elements of urban space. The segment of bars and restaurants falls within this context, therefore is a vital activity responsible for significant percentage of jobs and revenue in a city. Altogether, foods & beverages commercial activities move daily large volumes of goods to meet the need of customers. This paper presents the results of a freight trip generation model developed for pubs and restaurants in Belo Horizonte (Brazil. Once performed the model determined the number of trips generated per day per establishment. In order to expand the discrete result to a continuous one, the results were geographically interpolated to a continuous surface and extrapolated within the city limits. The data for the freight trip generation model were obtained by survey. For this, we designed a structured questionnaire to obtain information about goods, frequency, operational time, place of performance of the loading/unloading of goods, establishment size and the number of employees. Besides these information, we investigated the acceptance of alternative practices in the delivery of goods, such as off-peak delivery. To accomplish the proposed models, we applied a simple linear regression, correlating the following variables: (i Number of trips versus area of the establishment; (ii Number of trips versus number of employees; (iii Number of trips versus operation day of the establishment. With the results of the linear regression for travel generations, conducted the data interpolation based on the standard deviation of the results to define the sample

  18. Evidence Based Prevention of Occupational Slips, Trips and Falls

    DEFF Research Database (Denmark)

    Jensen, Olaf Chresten

    2009-01-01

    It is estimated that about one third of the compensated occupational injuries and half of the most serious occupational injuries in merchant seafaring are related to slips, trips and falls (STF)-events. Among the elderly, STF is the risk factor that causes the largest number of inpatient days...

  19. What drives people? Analyzing leisure-shopping trip decision making

    NARCIS (Netherlands)

    de Ceunynck, T.; Kusumastuti, Diana; Hannes, E.; Janssens, D.; Wets, G.

    2011-01-01

    Because of the strong increase in the number of leisure-shopping trips, a shift towards more sustainable leisure-shopping behaviour is desirable. This can be attained by having a better insight into people’s reasoning in choosing a transport mode and shopping location for this type of activities.

  20. Field Trip as an Effective Method of Teaching Apiculture/Beekeeping among University Students

    Directory of Open Access Journals (Sweden)

    Ja’afar-Furo, M. R.

    2017-03-01

    Full Text Available Various methods of teaching beekeeping in the very few institutions of higher learning that offer such courses have been studied. This survey attempted to review the numerous methods of instructions applied in achieving better learning outcomes on apiculture in tertiary institutions. Secondary information were mainly used to source for data for the survey. However, interview schedules were conducted to solicit for primary data from the students on their perception on best methodology for learning the subject. Descriptive statistics and percentage score were used to analyse the involvement of institutions in instructing learners, and capture learners’ perception on most preferred teaching methods of the course, respectively. Although findings indicated that a classroom lectures method, a combination of lecture and demonstration methods, field trip method, laboratory method, project methods, among others, existed as pedagogies used for ensuring that learners have had thorough understanding of the subject matter, majority of learners opted for the field trip method of teaching apiculture as the most preferred way of stimulating students toward enhanced learning outcomes. Based on the findings of the study, it’s concluded that a combination of field trip and lecture methods of instruction is the most effective way of teaching beekeeping in tertiary schools. Therefore, institutions and organisations of public and private origins that intend to improve on the knowledge of apiculture among youths and all, should capture field trip and lecture methods in their curricula of learning as the most preferred way of instruction.

  1. Push-off reactions in recovery after tripping discriminate young subjects, older non-fallers and older fallers

    NARCIS (Netherlands)

    Pijnappels, M.A.G.M.; Bobbert, M.F.; van Dieen, J.H.

    2005-01-01

    Tripping is a major cause for falls, especially in the elderly. This study investigated whether falls in the elderly can be attributed to inadequate push-off reactions by the support limb in the recovery after a trip. Twelve young (20-34 years) and eleven older (65-72 years) men and women walked

  2. Development of RPS trip logic based on PLD technology

    International Nuclear Information System (INIS)

    Choi, Jong Gyun; Lee, Dong Young

    2012-01-01

    The majority of instrumentation and control (I and C) systems in today's nuclear power plants (NPPs) are based on analog technology. Thus, most existing I and C systems now face obsolescence problems. Existing NPPs have difficulty in repairing and replacing devices and boards during maintenance because manufacturers no longer produce the analog devices and boards used in the implemented I and C systems. Therefore, existing NPPs are replacing the obsolete analog I and C systems with advanced digital systems. New NPPs are also adopting digital I and C systems because the economic efficiencies and usability of the systems are higher than the analog I and C systems. Digital I and C systems are based on two technologies: a microprocessor based system in which software programs manage the required functions and a programmable logic device (PLD) based system in which programmable logic devices, such as field programmable gate arrays, manage the required functions. PLD based systems provide higher levels of performance compared with microprocessor based systems because PLD systems can process the data in parallel while microprocessor based systems process the data sequentially. In this research, a bistable trip logic in a reactor protection system (RPS) was developed using very high speed integrated circuits hardware description language (VHDL), which is a hardware description language used in electronic design to describe the behavior of the digital system. Functional verifications were also performed in order to verify that the bistable trip logic was designed correctly and satisfied the required specifications. For the functional verification, a random testing technique was adopted to generate test inputs for the bistable trip logic.

  3. Analysis of reactor trips originating in balance of plant systems

    International Nuclear Information System (INIS)

    Stetson, F.T.; Gallagher, D.W.; Le, P.T.; Ebert, M.W.

    1990-09-01

    This report documents the results of an analysis of balance-of-plant (BOP) related reactor trips at commercial US nuclear power plants of a 5-year period, from January 1, 1984, through December 31, 1988. The study was performed for the Plant Systems Branch, Office of Nuclear Reactor Regulation, US Nuclear Regulatory Commission. The objectives of the study were: to improve the level of understanding of BOP-related challenges to safety systems by identifying and categorizing such events; to prepare a computerized data base of BOP-related reactor trip events and use the data base to identify trends and patterns in the population of these events; to investigate the risk implications of BOP events that challenge safety systems; and to provide recommendations on how to address BOP-related concerns in regulatory context. 18 refs., 2 figs., 27 tabs

  4. Laminar-turbulent transition tripped by step on transonic compressor profile

    Science.gov (United States)

    Flaszynski, Pawel; Doerffer, Piotr; Szwaba, Ryszard; Piotrowicz, Michal; Kaczynski, Piotr

    2018-02-01

    The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project (Transition Location Effect on Shock Wave Boundary Layer Interaction). The experimental and numerical results for the flow structure investigations are shown for the flow conditions as the existing ones on the suction side of the compressor profile. The two cases are investigated: without and with boundary layer tripping device. In the first case, boundary layer is laminar up to the shock wave, while in the second case the boundary layer is tripped by the step. Numerical results carried out by means of Fine/Turbo Numeca with Explicit Algebraic Reynolds Stress Model including transition modeling are compared with schlieren, Temperature Sensitive Paint and wake measurements. Boundary layer transition location is detected by Temperature Sensitive Paint.

  5. ITE Trip Generation Modification Factors for Louisiana : Research Project Capsule

    Science.gov (United States)

    2017-12-01

    Using data from studies conducted in the United States over the last 50-60 years, the Institute of Transportation Engineers (ITE) has published trip generation rates for different land uses. Over time, observations from new studies have been incorpor...

  6. Analyzing in rotating asynchronous machine MG set synchronising fault

    International Nuclear Information System (INIS)

    Lu Mingyang; Li Bo; Liu Yu; Fang Yinping

    2014-01-01

    In the commissioning work for MG set at FQNPC Unit l, MG-set l and MG-set 2 can not be synchronized lead to all two generator circuit breakers tripped. The description of the wave in the commissioning and the principle in phase compound excitation are all mentioned in this paper. After wave analysis and theory comparison, the direct cause of this problem is the reactive current in the two parallel synchronous generators, the real reason is parallel excitation contactor operation failed. Which could occur by these single failures, as follows, The synchronizing relay broken. The parallel excitation contactor occur the functional failure. The synchronizing signal trigger, and the order of execution about the breaker of generator and the parallel excitation contactor error. In order to solve these problem, regulating the voltage of generator is necessary. Redundant excitation contactor and relay is also need. After the maintenance, before the generator synchronized must test and verify the parallel excitation contactor works well. (authors)

  7. Analysis of 'human element related trip case book in Korean NPPs' using organizational factors

    International Nuclear Information System (INIS)

    Kim, S. Y.; Kim, Y. I.; Lee, Y. S.; Kim, C. S.; Jung, C. H.; Jung, W. D.

    2002-01-01

    There have been no studies appling organizational factors to data analysis in Korean NPPs. In this paper, data in 'human element related trip case book in Korean NPPs' are analyzed and categorized by the 20 organizational factors of NRC-BNL according to the cause of reactor trip. These inform us how organizational factors affected on the safety of Korean NPPs. Consequently important organizational factor are identified through which it is known that NPP organization would have a tendency

  8. Planning a pharmacy-led medical mission trip, part 4: an exploratory study of student experiences.

    Science.gov (United States)

    Brown, Dana A; Fairclough, Jamie L; Ferrill, Mary J

    2012-09-01

    At the Gregory School of Pharmacy (GSOP), pharmacy students routinely participate in domestic and international medical mission trips. Participation can be for academic credit as part of final-year Advanced Pharmacy Practice Experiences (APPEs) or as required community service hours. These mission experiences could potentially result in both professional and personal transformations for participating students. To evaluate data collected from GSOP pharmacy students regarding their experiences on the medical mission field in 2011 and how that participation has impacted the students professionally and personally. GSOP students participating in an international or domestic medical mission trip in the summer of 2011 were asked to voluntarily complete pre- and posttrip surveys. Of the 68 final-year APPE students and student volunteers who participated in a summer 2011 GSOP medical mission trip, 36 (53%) completed pre- and posttrip surveys. The mission trips significantly impacted students' beliefs regarding better preparation to care for the medical needs of patients, identification of others' needs, understanding team dynamics, perceptions about the value of patient care, and comfort level with the provision of medical and pharmaceutical care in a foreign country. However, there were no statistically significant improvements in students' perceptions of their ability to care for the emotional needs of patients, the importance of team unity, and their level of respect for team members; their ability to lead or participate in future trips; and their belief that participating preceptors and faculty serve as effective role models of servant leaders. Based on the findings from this exploratory study, participation in a domestic or international medical mission trip as a student volunteer or APPE student appears to have a positive impact on some of the beliefs and perceptions of GSOP students. By continuing to follow these particular students and similar cohorts of students in

  9. Investigation of the dielectric recovery in synthetic air in a high voltage circuit breaker

    International Nuclear Information System (INIS)

    Seeger, M; Naidis, G; Steffens, A; Nordborg, H; Claessens, M

    2005-01-01

    The dielectric recovery of an axially blown arc in an experimental set-up based on a conventional HV circuit breaker was investigated both experimentally and theoretically. As a quenching gas, synthetic air was used. The investigated time range was from 10 μs to 10 ms after current zero (CZ). A fast rise in the dielectric strength during the first 100 μs, followed by a plateau and further rise later was observed. The dependences on the breaking current and pressure were determined. The measured dielectric recovery during the first 100 μs after CZ could be reproduced with good accuracy by computational fluid dynamics simulations. From that it could be deduced that the temperature decay in the axis does not depend sensitively on the pressure. The dielectric recovery during the first 100 μs scales therefore mainly with the filling pressure. The plateau in the breakdown characteristic is due to a hot vapour layer from the still evaporating PTFE nozzle surface

  10. Transient studies in large offshore wind farms, taking into account network/circuit breaker interaction

    Energy Technology Data Exchange (ETDEWEB)

    Glasdam, Jakob; Hjerrild, Jesper; Arana, Ivan [DONG Energy Power A/S, Fredericia (Denmark); Bak, Claus Leth [Aalborg Univ. (Denmark). Inst. of Energy Technology

    2011-07-01

    Switching overvoltages (SOV) are considered a possible source of experienced component failures in existing offshore wind farms (OWFs). The inclusion of sufficiently accurate and validated models of the main components in the OWF in the simulation tool is therefore an important issue in order to ensure reliable switching operations. Transient measurement results in an OWF are compared with simulation results in PSCAD EMTDC and DigSILENT Power Factory, where a user-defined model of the vacuum circuit breaker (VCB) is included, capable of simulating multiple prestrikes during the closing operation. An analysis of the switching transients that might occur in an OWF will be made on basis of the validated model and the importance of the inclusion of a sufficient accurate representation of the VCB in the simulation tool will be described. The inclusion of the VCB model in PSCAD greatly improves the simulation results, whereas little improvement is found in DigSILENT. (orig.)

  11. The obesity-induced transcriptional regulator TRIP-Br2 mediates visceral fat endoplasmic reticulum stress-induced inflammation.

    Science.gov (United States)

    Qiang, Guifen; Kong, Hyerim Whang; Fang, Difeng; McCann, Maximilian; Yang, Xiuying; Du, Guanhua; Blüher, Matthias; Zhu, Jinfang; Liew, Chong Wee

    2016-04-25

    The intimate link between location of fat accumulation and metabolic disease risk and depot-specific differences is well established, but how these differences between depots are regulated at the molecular level remains largely unclear. Here we show that TRIP-Br2 mediates endoplasmic reticulum (ER) stress-induced inflammatory responses in visceral fat. Using in vitro, ex vivo and in vivo approaches, we demonstrate that obesity-induced circulating factors upregulate TRIP-Br2 specifically in visceral fat via the ER stress pathway. We find that ablation of TRIP-Br2 ameliorates both chemical and physiological ER stress-induced inflammatory and acute phase response in adipocytes, leading to lower circulating levels of inflammatory cytokines. Using promoter assays, as well as molecular and pharmacological experiments, we show that the transcription factor GATA3 is responsible for the ER stress-induced TRIP-Br2 expression in visceral fat. Taken together, our study identifies molecular regulators of inflammatory response in visceral fat that-given that these pathways are conserved in humans-might serve as potential therapeutic targets in obesity.

  12. Report on safety related occurrences and reactor trips July 1, 1977 - December 31, 1977

    International Nuclear Information System (INIS)

    Andermo, L.; Sundman, B.

    1974-04-01

    This is a systematically arranged report on all reported safety related occurrences and reactor trips in Swedish nuclear power plants in operation during July 1 to December 31, 1977 inclusive. The facilities involved are Barsebaeck 1 and 2, Oskarshamn 1 and 2 and Ringhals 1 and 2. During this period of 6 months 48 safety related occurrences and 49 reactor trips have been reported to the Nuclear Power Inspectorate. Included is also one incident June 21 in Barsebaeck 2 which was not included in the last compilation of occurrences. As earlier experiences have shown it is to the greatest extent the conventional components which bring about the safety related occurrences or occurrences leading to outages or power reductions. However, the component errors discovered in the safety related systems have not affected the function of their redundant systems and other diverse systems have not been involved. Therefore the reactor safety has been satisfactory. The total number of reactor trips have increased nearly 30% since the last period. Those occurred during power operation however, were less. More than 50% of the reactor trips happened in the shutdown condition. The fact that even small deviations from prescribed operation result in automatic and safe shut down of the reactor, does not always imply a conflict with operational availability. The greatest outages are caused by occurrences withou02068NRM 0000169 450

  13. The influence of artificially increased trunk stiffness on the balance recovery after a trip.

    Science.gov (United States)

    van der Burg, J C E; Pijnappels, M; van Dieën, J H

    2007-07-01

    Falls occur frequently in the growing population of elderly. Since trunk control is critical for maintaining balance, the higher trunk stiffness in elderly people compared to the general population has been associated with their increased fall-risk. Theoretically, trunk stiffness may be beneficial for balance recovery in walking, i.e. after a trip. A stiff joint may provide a torque that restricts the perturbation effects and thereby reduces the probability of a fall. The aim of this study was to test whether trunk stiffness impaired or assisted balance recovery after a trip during walking. An orthopedic corset was used to simulate trunk stiffness in 11 young male adults. Subjects walked over a platform, with or without the corset on, and were occasionally tripped over a hidden obstacle. Kinematics of the tripping reaction were measured. Initial trunk accelerations were significantly attenuated by the corset, which indicates a positive effect of the stiffening corset. However, no subsequent effects on peak trunk inclination and on the peak moment arm of gravity on the trunk were found. The pattern of trunk motion allowed ample time for triggered or voluntary muscle responses to be generated, before a substantial inclination occurred. It appears that such active responses were sufficient in the young subjects tested to obtain a similar net effect with or without the increased trunk stiffness induced by the corset.

  14. Design of Thermo Mechanicaln Processing and Transformation Behaviour of Bulk Si-Mn Trip Steel

    Directory of Open Access Journals (Sweden)

    Zrnik, J.

    2006-01-01

    Full Text Available In the last decade, a lot of effort has been paid to optimising the thermomechanical processing of TRIP steels that stands for transformation induced plasticity. The precise characterization of the resulting multiphase microstructure of low alloyed TRIP steels is of great importance for the interpretation and optimisation of their mechanical properties. The results obtained in situ neutron diffraction laboratory experiment concerning the austenite to ferrite transformation in Si-Mn bulk TRIP steel specimens, displaying the transformation induced plasticity (TRIP, are presented. The advancement of ferrite formation during transformation in conditioned austenite is investigated at different transformation temperatures and has been monitored using neutron diffraction method. The relevant information on transformation proceeding is extracted from neutron diffraction spectra. The integrated intensities of austenite and ferrite neutron diffraction profiles developed during the transformation are then assumed as a measure of the phase volume fractions of both phases in dependence on transformation temperature and austenite conditioning. According to the yielding information on ferrite volume fractions from isothermal transformation kinetics data the thermo mechanical processing of bulk specimen was designed in order to support austenite stabilization through bainitic transformation. The volume fractions of retained austenite resulting at alternating transformation conditions were measured by neutron and X-ray diffraction respectively. The stability of retained austenite in bulk specimens during room temperature mechanical testing was characterized by in situ neutron diffraction experiments as well.

  15. DISPAQ: Distributed Profitable-Area Query from Big Taxi Trip Data †

    Science.gov (United States)

    Putri, Fadhilah Kurnia; Song, Giltae; Rao, Praveen

    2017-01-01

    One of the crucial problems for taxi drivers is to efficiently locate passengers in order to increase profits. The rapid advancement and ubiquitous penetration of Internet of Things (IoT) technology into transportation industries enables us to provide taxi drivers with locations that have more potential passengers (more profitable areas) by analyzing and querying taxi trip data. In this paper, we propose a query processing system, called Distributed Profitable-Area Query (DISPAQ) which efficiently identifies profitable areas by exploiting the Apache Software Foundation’s Spark framework and a MongoDB database. DISPAQ first maintains a profitable-area query index (PQ-index) by extracting area summaries and route summaries from raw taxi trip data. It then identifies candidate profitable areas by searching the PQ-index during query processing. Then, it exploits a Z-Skyline algorithm, which is an extension of skyline processing with a Z-order space filling curve, to quickly refine the candidate profitable areas. To improve the performance of distributed query processing, we also propose local Z-Skyline optimization, which reduces the number of dominant tests by distributing killer profitable areas to each cluster node. Through extensive evaluation with real datasets, we demonstrate that our DISPAQ system provides a scalable and efficient solution for processing profitable-area queries from huge amounts of big taxi trip data. PMID:28946679

  16. Astronauts Armstrong and Aldrin study rock samples during field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, and Astronaut Edwin Aldrin, Lunar module pilot for Apollo 11, study rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  17. Identification of new TRIP12 variants and detailed clinical evaluation of individuals with non-syndromic intellectual disability with or without autism

    Science.gov (United States)

    Lüdecke, H.-J.; Pettersson, M.; Albrecht, B.; Bernier, R. A.; Cremer, K.; Eichler, E. E.; Falkenstein, D.; Gerdts, J.; Jansen, S.; Kuechler, A.; Kvarnung, M.; Lindstrand, A.; Nilsson, D.; Nordgren, A.; Pfundt, R.; Spruijt, L.; Surowy, H. M.; de Vries, B. B. A.; Wieland, T.; Engels, H.; Strom, T. M.; Kleefstra, T.; Wieczorek, D.

    2018-01-01

    The ubiquitin pathway is an enzymatic cascade including activating E1, conjugating E2, and ligating E3 enzymes, which governs protein degradation and sorting. It is crucial for many physiological processes. Compromised function of members of the ubiquitin pathway leads to a wide range of human diseases, such as cancer, neurodegenerative diseases, and neurodevelopmental disorders. Mutations in the thyroid hormone receptor interactor 12 (TRIP12) gene (OMIM 604506), which encodes an E3 ligase in the ubiquitin pathway, have been associated with autism spectrum disorder (ASD). In addition to autistic features, TRIP12 mutation carriers showed intellectual disability (ID). More recently, TRIP12 was postulated as a novel candidate gene for intellectual disability in a meta-analysis of published ID cohorts. However, detailed clinical information characterizing the phenotype of these individuals was not provided. In this study, we present seven novel individuals with private TRIP12 mutations including two splice site mutations, one nonsense mutation, three missense mutations, and one translocation case with a breakpoint in intron 1 of the TRIP12 gene and clinically review four previously published cases. The TRIP12 mutation-positive individuals presented with mild to moderate ID (10/11) or learning disability [intelligence quotient (IQ) 76 in one individual], ASD (8/11) and some of them with unspecific craniofacial dysmorphism and other anomalies. In this study, we provide detailed clinical information of 11 TRIP12 mutation-positive individuals and thereby expand the clinical spectrum of the TRIP12 gene in non-syndromic intellectual disability with or without ASD. PMID:27848077

  18. HUWE1 and TRIP12 collaborate in degradation of ubiquitin-fusion proteins and misframed ubiquitin.

    Directory of Open Access Journals (Sweden)

    Esben G Poulsen

    Full Text Available In eukaryotic cells an uncleavable ubiquitin moiety conjugated to the N-terminus of a protein signals the degradation of the fusion protein via the proteasome-dependent ubiquitin fusion degradation (UFD pathway. In yeast the molecular mechanism of the UFD pathway has been well characterized. Recently the human E3 ubiquitin-protein ligase TRIP12 was connected with the UFD pathway, but little is otherwise known about this system in mammalian cells. In the present work, we utilized high-throughput imaging on cells transfected with a targeted siRNA library to identify components involved in degradation of the UFD substrate Ub(G76V-YFP. The most significant hits from the screen were the E3 ubiquitin-protein ligase HUWE1, as well as PSMD7 and PSMD14 that encode proteasome subunits. Accordingly, knock down of HUWE1 led to an increase in the steady state level and a retarded degradation of the UFD substrate. Knock down of HUWE1 also led to a stabilization of the physiological UFD substrate UBB(+1. Precipitation experiments revealed that HUWE1 is associated with both the Ub(G76V-YFP substrate and the 26S proteasome, indicating that it functions late in the UFD pathway. Double knock down of HUWE1 and TRIP12 resulted in an additive stabilization of the substrate, suggesting that HUWE1 and TRIP12 function in parallel during UFD. However, even when both HUWE1 and TRIP12 are downregulated, ubiquitylation of the UFD substrate was still apparent, revealing functional redundancy between HUWE1, TRIP12 and yet other ubiquitin-protein ligases.

  19. Geologic field-trip guide to Medicine Lake Volcano, northern California, including Lava Beds National Monument

    Science.gov (United States)

    Donnelly-Nolan, Julie M.; Grove, Timothy L.

    2017-08-17

    Medicine Lake volcano is among the very best places in the United States to see and walk on a variety of well-exposed young lava flows that range in composition from basalt to rhyolite. This field-trip guide to the volcano and to Lava Beds National Monument, which occupies part of the north flank, directs visitors to a wide range of lava flow compositions and volcanic phenomena, many of them well exposed and Holocene in age. The writing of the guide was prompted by a field trip to the California Cascades Arc organized in conjunction with the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) quadrennial meeting in Portland, Oregon, in August of 2017. This report is one of a group of three guides describing the three major volcanic centers of the southern Cascades Volcanic Arc. The guides describing the Mount Shasta and Lassen Volcanic Center parts of the trip share an introduction, written as an overview to the IAVCEI field trip. However, this guide to Medicine Lake volcano has descriptions of many more stops than are included in the 2017 field trip. The 23 stops described here feature a range of compositions and volcanic phenomena. Many other stops are possible and some have been previously described, but these 23 have been selected to highlight the variety of volcanic phenomena at this rear-arc center, the range of compositions, and for the practical reason that they are readily accessible. Open ground cracks, various vent features, tuffs, lava-tube caves, evidence for glaciation, and lava flows that contain inclusions and show visible evidence of compositional zonation are described and visited along the route.

  20. Effects of delayed RCP trip during SBLOCA in PWR

    International Nuclear Information System (INIS)

    Montero-Mayorga, J.; Queral, C.; Gonzalez-Cadelo, J.

    2014-01-01

    Highlights: • Review of RCP trip issue in case of SBLOCA showing adequacy of present EOPs. • Risk assessment of a SBLOCA deterministic safety analysis by means of ISA methodology. • Evaluation of the probability of damage considering uncertainties in operator actuation times. • Application of ISA methodology to probabilistic safety analysis. • Obtaining of RCP trip available time as function of break size. - Abstract: After the Three Mile Island (TMI) accident, the issue of when to trip the Reactor Coolant Pumps (RCPs) in case of a Small Break Loss of Coolant Accident (SBLOCA) became very important. Several analyses were performed during the 1980s leading to the current Emergency Operating Procedures (EOPs). However these analyses have not been reviewed taking into account that several improvements have been performed in the last thirty years with respect to two phase-flow models, thermal–hydraulics codes and safety assessment methodologies. In this sense, this work has two main objectives: First of all, an assessment of the analyses carried out by Pressurizer Water Reactor (PWR) vendors after the TMI-2 accident with a model of Almaraz Nuclear Power Plant (NPP) for TRACE code (V 5.0 patch 1). On the other hand, Integrated Safety Assessment (ISA) methodology is applied to explore this matter. Such methodology has been developed by the Spanish Nuclear Safety Council (CSN) and it is an adequate method to perform analyses in nuclear safety in which the uncertainties in operator actuation time play an important role. The main conclusions obtained from this work are that, the current EOPs are adequate to manage a SBLOCA sequence in a suitable manner and that ISA methodology is a powerful tool that provides accurate information to the analyst in order to verify the robustness of the EOPs and to perform the safety assessment of both, deterministic and probabilistic safety analysis

  1. RELAP5/MOD 3.3 analysis of Reactor Coolant Pump Trip event at NPP Krsko

    International Nuclear Information System (INIS)

    Bencik, V.; Debrecin, N.; Foretic, D.

    2003-01-01

    In the paper the results of the RELAP5/MOD 3.3 analysis of the Reactor Coolant Pump (RCP) Trip event at NPP Krsko are presented. The event was initiated by an operator action aimed to prevent the RCP 2 bearing damage. The action consisted of a power reduction, that lasted for 50 minutes, followed by a reactor and a subsequent RCP 2 trip when the reactor power was reduced to 28 %. Two minutes after reactor trip, the Main Steam Isolation Valves (MSIV) were isolated and the steam dump flow was closed. On the secondary side the Steam Generator (SG) pressure rose until SG 1 Safety Valve (SV) 1 opened. The realistic RELAP5/MOD 3.3 analysis has been performed in order to model the particular plant behavior caused by operator actions. The comparison of the RELAP5/MOD 3.3 results with the measurement for the power reduction transient has shown small differences for the major parameters (nuclear power, average temperature, secondary pressure). The main trends and physical phenomena following the RCP Trip event were well reproduced in the analysis. The parameters that have the major influence on transient results have been identified. In the paper the influence of SG 1 relief and SV valves on transient results was investigated more closely. (author)

  2. Round-Trip System Available to Measure Path Length Variation in Korea VLBI System for Geodesy

    Science.gov (United States)

    Oh, Hongjong; Kondo, Tetsuro; Lee, Jinoo; Kim, Tuhwan; Kim, Myungho; Kim, Suchul; Park, Jinsik; Ju, Hyunhee

    2010-01-01

    The construction project of Korea Geodetic VLBI officially started in October 2008. The construction of all systems will be completed by the end of 2011. The project was named Korea VLBI system for Geodesy (KVG), and its main purpose is to maintain the Korea Geodetic Datum. In case of the KVG system, an observation room with an H-maser frequency standard is located in a building separated from the antenna by several tens of meters. Therefore KVG system will adopt a so-called round-trip system to transmit reference signals to the antenna with reduction of the effect of path length variations. KVG s round-trip system is designed not only to use either metal or optical fiber cables, but also to measure path length variations directly. We present this unique round trip system for KVG.

  3. Exploration of spatio-temporal patterns of students' movement in field trip by visualizing the log data

    Science.gov (United States)

    Cho, Nahye; Kang, Youngok

    2018-05-01

    A numerous log data in addition to user input data are being generated as mobile and web users continue to increase recently, and the studies in order to explore the patterns and meanings of various movement activities by making use of these log data are also rising rapidly. On the other hand, in the field of education, people have recognized the importance of field trip as the creative education is highlighted. Also, the examples which utilize the mobile devices in the field trip in accordance to the development of information technology are growing. In this study, we try to explore the patterns of student's activity by visualizing the log data generated from high school students' field trip with mobile device.

  4. Field trips as an intervention to enhance pharmacy students' positive ...

    African Journals Online (AJOL)

    To determine whether students' experience of field trips influenced their perceptions regarding a management module as part of their training as future pharmacists. Methods. A mixed-method sequential exploratory research design was used. Data were gathered through written narratives and focus group interviews, ...

  5. Social media in tourism: Establishing factors influencing attitudes towards the usage of social networking sites for trip organisation

    Directory of Open Access Journals (Sweden)

    Rosemary Matikiti

    2017-01-01

    Full Text Available Purpose: The main aim of this study was to determine the attitude towards the use of SNSs for trip organisation and its precursors. Problem investigated: Tourism organisations and destination policy makers need to understand factors that influence tourist use of SNSs for trip organisation in order for them to be able to effectively utilise SNSs. Methodology: The methodological approach followed was exploratory and quantitative in nature. Data were collected from a total of 340 respondents using a structured questionnaire. Structural equation modelling through the use of Partial Least Squares was for data analysis. Findings and implications: The results show that attitude towards the use of SNSs for trip organisation is affected by perceived benefits, subjective norm and perceived behavioural control, with perceived usefulness having the greatest influence. The implication is that managers of tourism organisations need to ensure that their sites are informative, easy to use and able to safeguard users’ online privacy if they are to attract more and loyal users to their sites. Value of the research: Very little research in the South African context exists with specific reference to how SNSs are being utilised for trip organisation. This article contributes by unravelling factors that influence the use of SNSs for trip organisation. Conclusion: Perceived usefulness measured by functional benefits and social benefits is the key factor that influences attitude towards the use of SNSs for trip organisation. It is the responsibility of destination marketers to provide all the necessary or valuable information on their SNS accounts, in order to encourage travellers to use SNSs

  6. Bainite transformation and TRIP effect in 20Mn2SiVB steel

    International Nuclear Information System (INIS)

    Huo Yanqiu; Long Xiuhui; Zhou Zhenhua; Li Jianguo

    2006-01-01

    Transformation-induced plasticity (TRIP) steel is a relatively new type of automotive steel known for its combination of high-strength and high ductility which was developed in the 1990s. 20Mn2SiVB steel is a kind of TRIP steel with low-carbon and low-alloying contents and high-strength. Specimens of a tested 20Mn2SiVB steel austenitized at 920 deg. C and austempered at 420 deg. C in a salt bath at different time are investigated. The microstructure obtained is studied by means of optical microscopy, scanning electron microscopy and X-ray diffraction. The results show that bainitic ferrite precipitates at the boundary of the austenite first, and with the prolongation of the isothermal time, the amount of bainitic ferrite increase. Then the ferrite decollates the austenite grain and lath-shaped bainitic ferrite with little island-shaped austenite forms during the holding time. The microstructure contains carbide-free bainite, granular bainite, retained austenite and martensite in the process of bainite transformation. Tensile test of the different treated specimens indicates that a better comprehensive property can be gained after austenized at 920 deg. C following austempered at 420 deg. C for 5 min, a certain TRIP effect can be also obtained under this condition

  7. Labeling Residential Community Characteristics from Collective Activity Patterns Using Taxi Trip Data

    Science.gov (United States)

    Zhou, Y.; Fang, Z.

    2017-09-01

    There existing a significant social and spatial differentiation in the residential communities in urban city. People live in different places have different socioeconomic background, resulting in various geographically activity patterns. This paper aims to label the characteristics of residential communities in a city using collective activity patterns derived from taxi trip data. Specifically, we first present a method to allocate the O/D (Origin/Destination) points of taxi trips to the land use parcels where the activities taken place in. Then several indices are employed to describe the collective activity patterns, including both activity intensity, travel distance, travel time, and activity space of residents by taking account of the geographical distribution of all O/Ds of the taxi trip related to that residential community. Followed by that, an agglomerative hierarchical clustering algorithm is introduced to cluster the residential communities with similar activity patterns. In the case study of Wuhan, the residential communities are clearly divided into eight clusters, which could be labelled as ordinary communities, privileged communities, old isolated communities, suburban communities, and so on. In this paper, we provide a new perspective to label the land use under same type from people's mobility patterns with the support of big trajectory data.

  8. Implementation of a roughness element to trip transition in large-eddy simulation

    Science.gov (United States)

    Boudet, J.; Monier, J.-F.; Gao, F.

    2015-02-01

    In aerodynamics, the laminar or turbulent regime of a boundary layer has a strong influence on friction or heat transfer. In practical applications, it is sometimes necessary to trip the transition to turbulent, and a common way is by use of a roughness element ( e.g. a step) on the wall. The present paper is concerned with the numerical implementation of such a trip in large-eddy simulations. The study is carried out on a flat-plate boundary layer configuration, with Reynolds number Rex=1.3×106. First, this work brings the opportunity to introduce a practical methodology to assess convergence in large-eddy simulations. Second, concerning the trip implementation, a volume source term is proposed and is shown to yield a smoother and faster transition than a grid step. Moreover, it is easier to implement and more adaptable. Finally, two subgrid-scale models are tested: the WALE model of Nicoud and Ducros ( Flow Turbul. Combust., vol. 62, 1999) and the shear-improved Smagorinsky model of Lévêque et al. ( J. Fluid Mech., vol. 570, 2007). Both models allow transition, but the former appears to yield a faster transition and a better prediction of friction in the turbulent regime.

  9. Development of a Trip Energy Estimation Model Using Real-World Global Positioning System Driving Data: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Holden, Jacob [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wood, Eric W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhu, Lei [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gonder, Jeffrey D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tian, Ye [Metropia, Inc.

    2017-09-15

    A data-driven technique for estimation of energy requirements for a proposed vehicle trip has been developed. Based on over 700,000 miles of driving data, the technique has been applied to generate a model that estimates trip energy requirements. The model uses a novel binning approach to categorize driving by road type, traffic conditions, and driving profile. The trip-level energy estimations can easily be aggregated to any higher-level transportation system network desired. The model has been tested and validated on the Austin, Texas, data set used to build this model. Ground-truth energy consumption for the data set was obtained from Future Automotive Systems Technology Simulator (FASTSim) vehicle simulation results. The energy estimation model has demonstrated 12.1 percent normalized total absolute error. The energy estimation from the model can be used to inform control strategies in routing tools, such as change in departure time, alternate routing, and alternate destinations, to reduce energy consumption. The model can also be used to determine more accurate energy consumption of regional or national transportation networks if trip origin and destinations are known. Additionally, this method allows the estimation tool to be tuned to a specific driver or vehicle type.

  10. Protection coordination of the Kennedy Space Center electric distribution network

    Science.gov (United States)

    1976-01-01

    A computer technique is described for visualizing the coordination and protection of any existing system of devices and settings by plotting the tripping characteristics of the involved devices on a common basis. The program determines the optimum settings of a given set of protective devices and configuration in the sense of the best expected coordinated operation of these devices. Subroutines are given for simulating time versus current characteristics of the different relays, circuit breakers, and fuses in the system; coordination index computation; protection checks; plotting; and coordination optimation.

  11. A Transformative Undergraduate Field Trip to the Grand Canyon and Death Valley

    Science.gov (United States)

    Smith, J. A.

    2014-12-01

    Seeing the iconic Grand Canyon and Death Valley in person is a transformative experience for most geologists, including nine undergraduate geology students from upstate New York. The students were enrolled in a one-credit course designed around a nine-day spring-break field trip to Grand Canyon National Park (GCNP) and Death Valley National Park (DVNP). We met once a week before the trip to plan day-to-day activities and discuss background geologic information. Students selected a research topic related to our itinerary and wrote a guidebook entry for the topic. Students' entries were combined with papers, maps, and background material to make a guidebook. The printed guidebooks provided students with a "publication" of their work to show to others and refer to in the field. The nine-day field trip started with a flight into Las Vegas, NV, on 3/1/14. We spent three nights camping at the South Rim of the Grand Canyon, one night camping in Valley of Fire State Park (VOFSP, 55 mi N of Las Vegas), and three nights staying at the Shoshone Education and Research Center (SHEAR) east of Death Valley. Highlights of the trip included the hike along the Bright Angel Trail (and fault) to Plateau Point and recognition of the Great Unconformity at GCNP; the White Domes loop hike, camping at the Beehives, and observation of the Muddy Mountain Overthrust in VOFSP; and hikes at Ubehebe Crater, Badwater Salt Flat, and Natural Bridge Canyon in DVNP. Each student presented his/her research topic at a pertinent point in the field trip; students were impressively well-prepared. One requirement of the course was a poster presentation on each student's research topic at our Undergraduate Research Symposium in April. For most of the students, the poster session was the first experience preparing and presenting a poster. In addition, the class gave a joint colloquium presentation to several hundred science majors and a number of science faculty at Saint Rose. Each student spoke for five

  12. Journal of South African Trip: January 14-March 1, 1986.

    Science.gov (United States)

    Rogers, Carl R.

    1987-01-01

    Provides a personal account, dictated en route, of Carl Rogers' experiences during his trip to South Africa. Documents extensive commitment to people and to a process leading to peace. Journal ends with conviction that violence can be avoided and that no group really wants violence. (Author)

  13. Pure intelligent monitoring system for steam economizer trips

    Directory of Open Access Journals (Sweden)

    Basim Ismail Firas

    2017-01-01

    Full Text Available Steam economizer represents one of the main equipment in the power plant. Some steam economizer's behavior lead to failure and shutdown in the entire power plant. This will lead to increase in operating and maintenance cost. By detecting the cause in the early stages maintain normal and safe operational conditions of power plant. However, these methodologies are hard to be achieved due to certain boundaries such as system learning ability and the weakness of the system beyond its domain of expertise. The best solution for these problems, an intelligent modeling system specialized in steam economizer trips have been proposed and coded within MATLAB environment to be as a potential solution to insure a fault detection and diagnosis system (FDD. An integrated plant data preparation framework for 10 trips was studied as framework variables. The most influential operational variables have been trained and validated by adopting Artificial Neural Network (ANN. The Extreme Learning Machine (ELM neural network methodology has been proposed as a major computational intelligent tool in the system. It is shown that ANN can be implemented for monitoring any process faults in thermal power plants. Better speed of learning algorithms by using the Extreme Learning Machine has been approved as well.

  14. The trade-off between trips and distance travelled in analyzing the emissions impacts of center-based telecommuting

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtarian, P.L. [University of California, Davis, CA (United States). Dept. of Dept. of Civil and Environmental Engineering and Institute of Transportation Studies; Varma, K.V. [Decision Focus Inc., Mountain View, CA (United States)

    1998-11-01

    Several travel indicators were compared between telecommuting (TC) days and non-telecommuting days for a sample of 72 center-based telecommuters in California. Distance travelled decreased significantly on TC days, with average reductions of 51 person-miles (58%) and 35 vehicle-miles (53%). When weighted by telecommuting frequency, average reductions of 11.9% in PMT and 11.5% in VMT were found over a five-day work week. Person-trips and vehicle-trips increased slightly (but not significantly) on TC days. Despite the increase in trip rates, TC-day reductions were found for all pollutants analyzed: 15% for total organic gas emissions, 21% for carbon monoxide, 35% for oxides of nitrogen, and 51% for particulate matter. (author)

  15. Field trip guidebook for the post-meeting field trip: The Central Appalachians

    Science.gov (United States)

    Taylor, John F.; Loch, James D.; Ganis, G. Robert; Repetski, John E.; Mitchell, Charles E.; Blackmer, Gale C.; Brezinski, David K.; Goldman, Daniel; Orndorff, Randall C.; Sell, Bryan K.

    2015-01-01

    The lower Paleozoic rocks to be examined on this trip through the central Appalachians represent an extreme range of depositional environments. The lithofacies we will examine range from pelagic radiolarian chert and interbedded mudstone that originated on the deep floor of the Iapetus Ocean, through mud cracked supratidal dolomitic laminites that formed during episodes of emergence of the long-lived Laurentian carbonate platform, to meandering fluvial conglomerate and interstratified overbank mudstone packages deposited in the latest stages of infilling of the Taconic foredeep. In many ways this field trip is about contrasts. The Upper Cambrian (Furongian) and Lower Ordovician deposits of the Sauk megasequence record deposition controlled primarily by eustatic sea level sea level fluctuations that influenced deposition along the passive, southern (Appalachian) margin of the paleocontinent of Laurentia. The only tectonic influence apparent in these passive margin deposits is the expected thickening of the carbonate stack toward the platform margin as compared to the thinner (and typically shallower) facies that formed farther in toward the paleoshoreline. Carbonates overwhelmingly dominate the passive margin succession. Clastic influx was minimal and consisted largely of eastward transport of clean cratonic sands across the platform from the adjacent inner detrital belt to the west during higher order (2nd and 3rd order) regressions.In contrast, Middle and Upper Ordovician deposits of the Tippecanoe megasequence record the strong influence of tectonics, specifically Iapetus closure. The first signal of this tectonic transformation was the arrival of arc-related ash beds that abound in the active margin carbonates. Subsequent intensification of Taconic orogenesis resulted in the foundering of the carbonate platform under the onslaught of fine siliciclastics arriving from offshore tectonic sources to the east, creating a deep marine flysch basin where graptolitic

  16. Geographical and Statistical Analysis on the Relationship between Land-Use Mixture and Home-Based Trip Making and More: Case of Richmond, Virginia

    Directory of Open Access Journals (Sweden)

    Yin - Shan MA

    2013-06-01

    Full Text Available Richmond, Virginia has implemented numerous mixed land-use policies to encourage non-private-vehicle commuting for decades based on the best practices of other cities and the assumption that land-use mixture would positively lead to trip reduction. This paper uses both Geographical Information Systems (GIS and statistical tools to empirically test this hypothesis. With local land use and trip making data as inputs, it first calculates two common indices of land-use mixture - entropy and dissimilarity indices, using GIS tool, supplemented by Microsoft Excel. Afterwards, it uses Statistical Package for Social Sciences (SPSS to calculate the correlation matrices among land-use mixture indices, socioeconomic variables, and home-based work/other trip rates, followed by a series of regression model runs on these variables. Through this study, it has been found that land-use mixture has some but weak effects on home-based work trip rate, and virtually no effects on home-based other trip rate. In contrast, socioeconomic variables, especially auto ownership, have larger effects on home-based trip making.

  17. Uncertainty analysis of one Main Circulation Pump trip event at the Ignalina NPP

    International Nuclear Information System (INIS)

    Vileiniskis, V.; Kaliatka, A.; Uspuras, E.

    2004-01-01

    One Main Circulation Pump (MCP) trip event is an anticipated transient with expected frequency of approximately one event per year. There were a few events when one MCP was inadvertently tripped. The throughput of the rest running pumps in the affected Main Circulation Circuit loop increased, however, the total coolant flow through the affected loop decreased. The main question arises whether this coolant flow rate is sufficient for adequate core cooling. This paper presents an investigation of one MCP trip event at the Ignalina NPP. According to international practice, the transient analysis should consist of deterministic analysis by employing best-estimate codes and uncertainty analysis. For that purpose, the plant's RELAP5 model and the GRS (Germany) System for Uncertainty and Sensitivity Analysis package (SUSA) were employed. Uncertainty analysis of flow energy loss in different parts of the Main Circulation Circuit, initial conditions and code-selected models was performed. Such analysis allows to estimate the influence of separate parameters on calculation results and to find the modelling parameters that have the largest impact on the event studied. On the basis of this analysis, recommendations for the further improvement of the model have been developed. (author)

  18. The Field Trip Book: Study Travel Experiences in Social Studies

    Science.gov (United States)

    Morris, Ronald V.

    2010-01-01

    Looking for social studies adventures to help students find connections to democratic citizenship? Look no further! This book provides just the answer teachers need for engaging students in field trips as researching learners with emphasis on interdisciplinary social studies plus skills in collecting and reporting data gathered from field…

  19. The Goat Portage: Students' Stories and Learning from Canoe Trips.

    Science.gov (United States)

    Horwood, Bert

    This study explores how high school students learn from their experiences in an extracurricular adventure program and illustrates how students' narrative inquiries relate to experiential learning. Twelve canoe trips were studied by participant observation methods. Data were collected from recorded interviews with students and staff, field notes,…

  20. A No-Arc DC Circuit Breaker Based on Zero-Current Interruption

    Science.gov (United States)

    Xiang, Xuewei; Chai, Jianyun; Sun, Xudong

    2017-05-01

    A dc system has no natural current zero-crossing point, so a dc arc is more difficult to extinguish than an ac arc. In order to effectively solve the problem of the dc arc, this paper proposes a dc circuit breaker (DCCB) capable of implementing a no-arc interruption. The proposed DCCB includes a main branch consisting of a mechanical switch, a diode and a current-limiting inductor, a semi-period resonance circuit consisting of a diode, an inductor and a capacitor, and a buffer branch consisting of a capacitor, a thyristor and a resistor. The mechanical switch is opened in a zero-current state, and the overvoltage caused by the counter electromotive force of the inductor does not exist. Meanwhile, the capacitor has a buffering effect on the voltage. The rising of the voltage of the mechanical switch is slower than the rising of the insulating strength of a contact gap of the mechanical switch, resulting in the contact gap not able to be broken down. Thus, the arc cannot be generated. The simulation results show that the proposed DCCB does not generate the arc in the interruption process, the rise rate of the short circuit current can be effectively limited, and the short circuit fault point can be rapidly isolated from the dc power supply.

  1. Proposal for Remodeling the Sedimentation System of the CONCREPAL Material Breaker at Barranca, Costa Rica

    Directory of Open Access Journals (Sweden)

    Nazareth Arguedas-Zumbado

    2016-08-01

    Full Text Available Due to a change in environmental paradigm and the production increase, this document is a proposal for remodeling the CONCREPAL’s settler located in Barranca, Costa Rica. It is presented as an eco-efficient alternative that simultaneously enables compliance with current legislation on landfill and wastewater reuse. Initially, an environmental diagnosis of the characteristics and performance of the current sedimentation tank was made. Subsequently, the design of the proposed remodeling of the treatment system, incorporating the recirculation of treated water in the breaker material production process, was developed. Finally, a life-size settler model was created in a test environment in order to start measurements tests and determine the functionality; successfully, after all tests, positive results within the range allowed by national legislation on total suspended-solids concentration (40 ± 0.01 mg/l were obtained. Thanks to the cost-benefit and environmental management analysis, a new settler system can be implemented with positive short and long term results for the company.

  2. The Euler-Mascheroni Constant and The Car Talk Trip

    Science.gov (United States)

    Lynch, Frank H.; Page, Breeanna S.

    2018-01-01

    This paper uses the lens of a calculus student to examine different solutions to a weekly puzzler from the radio show "Car Talk," hosted by Tom and Ray Magliozzi. The puzzler describes an automobile that is traveling 75 miles per hour and is 75 miles from its destination. The trip is completed by traveling 1 mile at 75 miles per hour, 1…

  3. Hunton Group core workshop and field trip

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, K.S. [ed.

    1993-12-31

    The Late Ordovician-Silurian-Devonian Hunton Group is a moderately thick sequence of shallow-marine carbonates deposited on the south edge of the North American craton. This rock unit is a major target for petroleum exploration and reservoir development in the southern Midcontinent. The workshop described here was held to display cores, outcrop samples, and other reservoir-characterization studies of the Hunton Group and equivalent strata throughout the region. A field trip was organized to complement the workshop by allowing examination of excellent outcrops of the Hunton Group of the Arbuckle Mountains.

  4. Process Control Logic Modification to Mitigate Transient Following Tripping of a Primary Circulating Pump for a 540 MWe PHWR Power Plant

    International Nuclear Information System (INIS)

    Contractor, Ankur D; Gaikwad, Avinash J.; Kumar, Rajesh; Chakraborty, G.; Vhora, S.F.

    2006-01-01

    The 540 MWe Indian Pressurised Heavy Water Reactor (PHWR) incorporates many new features as compared to the earlier 220 MWe PHWRs. To evaluate the new design features like Primary Heat Transport (PHT) system configuration with two loops, four Primary Circulating Pumps (PCPs) and four passes through core, addition of a Pressurizer (surge Tank) in the PHT system along with Feed/Bleed system and their safety related implications, simulation model have been developed. A reactor step-back is proposed following one PCP trip. The corresponding PCP in the healthy loop is tripped to avoid asymmetrical flow and pressure distribution in the two identical loops. In spite of such elaborate provisions, the margins from high/low PHT pressure are small following tripping of one PCP. Mathematical models for all the major components and sub-systems of the proposed 540 MWe PHWR were developed based on the conservation equations of mass, momentum, energy and equation of state. All the associated control systems are also modeled. The PHT system includes the reactor core with nuclear fuel, PCP, PHT system pressure controller with feed/bleed system and Pressurizer (Surge Tank). The secondary system includes mainly the Steam Generators (SGs), the SG level and pressure controllers, apart from the various steam cycle components. All these models are integrated together to form the Plant Transient Analysis Computer Code Dyna540. The scenario following one PCP trips leads to different states (high/low pressure in Reactor Outlet Header (ROH)) depending upon the banks in which the PCP trips. The pressurizer is connected to two ROHs on one side of the reactor. The system pressure is controlled based on average of four ROHs pressure. In the case of asymmetrical pump operation, this logic leads to a situation where individual ROH pressure goes very near the low/high PHT system pressure trip set point, even though the controlled average pressure is very close to the set pressure. The PHT high

  5. Teaching and Learning in the Tropics: An Epistemic Exploration of "the Field" in a Development Studies Field Trip

    Science.gov (United States)

    Patel, Kamna

    2015-01-01

    Development studies employs theories, tools and methods often found in geography, including the international field trip to a "developing" country. In 2013 and 2014, I led a two-week trip to Ethiopia. To better comprehend the effects of "the field" on students' learning, I introduced an assessed reflexive field diary to…

  6. Trip Reports. Hazardous Waste Minimization and Control at Army Depots

    Science.gov (United States)

    1989-08-01

    Chief, Building 114; Major Robert Ronne; and Ken Rollins, Section Chief, Building 409. The purpose of this trip report Is to document the Information...hazardous. 6. Wf-TIM WOR Feosbility of a suitable p-etresaent f waste cuttins oil and sulleln coolant loach as 4iltratlan to remove metals. removal

  7. Transient Studies in Large Offshore Wind Farms Employing Detailed Circuit Breaker Representation

    Directory of Open Access Journals (Sweden)

    Jesper Hjerrild

    2012-07-01

    Full Text Available Switching overvoltages (SOV are considered a possible source of component failures experienced in existing offshore wind farms (OWFs. The inclusion of sufficiently accurate and validated models of the main electrical components in the OWF in the simulation tool is therefore an important issue in order to ensure reliable switching operations. Transient measurement results in an OWF are compared with simulation results in PSCAD EMTDC and DigSILENT Power Factory. A user-defined model of the vacuum circuit breaker (VCB is included in both tools, capable of simulating multiple prestrikes during the closing operation. An analysis of the switching transients that might occur in OWFs will be made on the basis of the validated model, and the importance of the inclusion of a sufficiently accurate representation of the VCB in the simulation tool will be described. The inclusion of the VCB model in PSCAD greatly improves the simulation results, whereas little improvement is found in DigSILENT. Based on the transient study it is found that the simulated SOV can be up to 60% higher at the sending end when using the detailed VCB representation compared to the built-in switch, which emphasises the need for accurate representation of the VCB for energisation studies.

  8. Uncovering patterns of inter-urban trip and spatial interaction from social media check-in data.

    Directory of Open Access Journals (Sweden)

    Yu Liu

    Full Text Available The article revisits spatial interaction and distance decay from the perspective of human mobility patterns and spatially-embedded networks based on an empirical data set. We extract nationwide inter-urban movements in China from a check-in data set that covers half a million individuals within 370 cities to analyze the underlying patterns of trips and spatial interactions. By fitting the gravity model, we find that the observed spatial interactions are governed by a power law distance decay effect. The obtained gravity model also closely reproduces the exponential trip displacement distribution. The movement of an individual, however, may not obey the same distance decay effect, leading to an ecological fallacy. We also construct a spatial network where the edge weights denote the interaction strengths. The communities detected from the network are spatially cohesive and roughly consistent with province boundaries. We attribute this pattern to different distance decay parameters between intra-province and inter-province trips.

  9. Uncovering patterns of inter-urban trip and spatial interaction from social media check-in data.

    Science.gov (United States)

    Liu, Yu; Sui, Zhengwei; Kang, Chaogui; Gao, Yong

    2014-01-01

    The article revisits spatial interaction and distance decay from the perspective of human mobility patterns and spatially-embedded networks based on an empirical data set. We extract nationwide inter-urban movements in China from a check-in data set that covers half a million individuals within 370 cities to analyze the underlying patterns of trips and spatial interactions. By fitting the gravity model, we find that the observed spatial interactions are governed by a power law distance decay effect. The obtained gravity model also closely reproduces the exponential trip displacement distribution. The movement of an individual, however, may not obey the same distance decay effect, leading to an ecological fallacy. We also construct a spatial network where the edge weights denote the interaction strengths. The communities detected from the network are spatially cohesive and roughly consistent with province boundaries. We attribute this pattern to different distance decay parameters between intra-province and inter-province trips.

  10. Uncovering Patterns of Inter-Urban Trip and Spatial Interaction from Social Media Check-In Data

    Science.gov (United States)

    Liu, Yu; Sui, Zhengwei; Kang, Chaogui; Gao, Yong

    2014-01-01

    The article revisits spatial interaction and distance decay from the perspective of human mobility patterns and spatially-embedded networks based on an empirical data set. We extract nationwide inter-urban movements in China from a check-in data set that covers half a million individuals within 370 cities to analyze the underlying patterns of trips and spatial interactions. By fitting the gravity model, we find that the observed spatial interactions are governed by a power law distance decay effect. The obtained gravity model also closely reproduces the exponential trip displacement distribution. The movement of an individual, however, may not obey the same distance decay effect, leading to an ecological fallacy. We also construct a spatial network where the edge weights denote the interaction strengths. The communities detected from the network are spatially cohesive and roughly consistent with province boundaries. We attribute this pattern to different distance decay parameters between intra-province and inter-province trips. PMID:24465849

  11. Combining gradient structure and TRIP effect to produce austenite stainless steel with high strength and ductility

    International Nuclear Information System (INIS)

    Wu, X.L.; Yang, M.X.; Yuan, F.P.; Chen, L.; Zhu, Y.T.

    2016-01-01

    We report a design strategy to combine the benefits from both gradient structure and transformation-induced plasticity (TRIP). The resultant TRIP-gradient steel takes advantage of both mechanisms, allowing strain hardening to last to a larger plastic strain. 304 stainless steel sheets were treated by surface mechanical attrition to synthesize gradient structure with a central coarse-grained layer sandwiched between two grain-size gradient layers. The gradient layer is composed of submicron-sized parallelepiped austenite domains separated by intersecting ε-martensite plates, with increasing domain size along the depth. Significant microhardness heterogeneity exists not only macroscopically between the soft coarse-grained core and the hard gradient layers, but also microscopically between the austenite domain and ε-martensite walls. During tensile testing, the gradient structure causes strain partitioning, which evolves with applied strain, and lasts to large strains. The γ → α′ martensitic transformation is triggered successively with an increase of the applied strain and flow stress. Importantly, the gradient structure prolongs the TRIP effect to large plastic strains. As a result, the gradient structure in the 304 stainless steel provides a new route towards a good combination of high strength and ductility, via the co-operation of both the dynamic strain partitioning and TRIP effect.

  12. Overview for geologic field-trip guides to Mount Mazama, Crater Lake Caldera, and Newberry Volcano, Oregon

    Science.gov (United States)

    Bacon, Charles R.; Donnelly-Nolan, Julie M.; Jensen, Robert A.; Wright, Heather M.

    2017-08-16

    These field-trip guides were written for the occasion of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) quadrennial scientific assembly in Portland, Oregon, in August 2017. The guide to Mount Mazama and Crater Lake caldera is an updated and expanded version of the guide (Bacon, 1989) for part of an earlier IAVCEI trip to the southern Cascade Range. The guide to Newberry Volcano describes the stops included in the 2017 field trip. Crater Lake and Newberry are the two best-preserved and most recent calderas in the Cascades Volcanic Arc. Although located in different settings in the arc, with Crater Lake on the arc axis and Newberry in the rear-arc, both volcanoes are located at the intersection of the arc and the northwest corner region of the extensional Basin and Range Province.

  13. The Ruthenostannylene Complex [Cp*(IXy)H2 Ru-Sn-Trip]: Providing Access to Unusual Ru-Sn Bonded Stanna-imine, Stannene, and Ketenylstannyl Complexes.

    Science.gov (United States)

    Liu, Hsueh-Ju; Ziegler, Micah S; Tilley, T Don

    2015-05-26

    Reactivity studies of the thermally stable ruthenostannylene complex [Cp*(IXy)(H)2 Ru-Sn-Trip] (1; IXy=1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene; Cp*=η(5) -C5 Me5 ; Trip=2,4,6-iPr3 C6 H2 ) with a variety of organic substrates are described. Complex 1 reacts with benzoin and an α,β-unsaturated ketone to undergo [1+4] cycloaddition reactions and afford [Cp*(IXy)(H)2 RuSn(κ(2) -O,O-OCPhCPhO)Trip] (2) and [Cp*(IXy)(H)2 RuSn(κ(2) -O,C-OCPhCHCHPh)Trip] (3), respectively. The reaction of 1 with ethyl diazoacetate resulted in a tin-substituted ketene complex [Cp*(IXy)(H)2 RuSn(OC2 H5 )(CHCO)Trip] (4), which is most likely a decomposition product from the putative ruthenium-substituted stannene complex. The isolation of a ruthenium-substituted stannene [Cp*(IXy)(H)2 RuSn(=Flu)Trip] (5) and stanna-imine [Cp*(IXy)(H)2 RuSn(κ(2) -N,O-NSO2 C6 H4 Me)Trip] (6) complexes was achieved by treatment of 1 with 9-diazofluorene and tosyl azide, respectively. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Field-trip guide to a volcanic transect of the Pacific Northwest

    Science.gov (United States)

    Geist, Dennis; Wolff, John; Harpp, Karen

    2017-08-01

    The Pacific Northwest region of the United States provides world-class and historically important examples of a wide variety of volcanic features. This guide is designed to give a broad overview of the region’s diverse volcanism rather than focusing on the results of detailed studies; the reader should consult the reference list for more detailed information on each of the sites, and we have done our best to recognize previous field trip leaders who have written the pioneering guides. This trip derives from one offered as a component of the joint University of Idaho- Washington State University volcanology class taught from 1995 through 2014, and it borrows in theme from the classic field guide of Johnston and Donnelly-Nolan (1981). For readers interested in using this field guide as an educational tool, we have included an appendix with supplemental references to resources that provide useful background information on relevant topics, as well as a few suggestions for field-based exercises that could be useful when bringing students to these locations in the future. The 4-day trip begins with an examination of lava flow structures of the Columbia River Basalt, enormous lava fields that were emplaced during one of the largest eruptive episodes in Earth’s recent history. On the second day, the trip turns to the High Lava Plains, a bimodal volcanic province that transgressed from southeast to northwest from the Miocene through the Holocene, at the northern margin of the Basin and Range Province. This volcanic field provides excellent examples of welded ignimbrite, silicic lavas and domes, monogenetic basaltic lava fields, and hydrovolcanic features. The third day is devoted to a circumnavigation of Crater Lake, the result of one of the world’s best-documented caldera-forming eruptions. The caldera walls also expose the anatomy of Mount Mazama, a stratovolcano of the Cascade Range. The last day is spent at Newberry Volcano, a back-arc shield volcano topped by a

  15. Texas trip generation manual : 1st edition-volume 1 : user's guide.

    Science.gov (United States)

    2014-08-01

    The purpose of this Manual is to provide a summary of Texas trip generation data for various : Land Use Codes (LUCs) and time periods, for data obtained from workplace and special : generator (WSG) surveys performed as part of the Texas Travel Survey...

  16. As armadilhas do tripé da política macroeconômica brasileira

    Directory of Open Access Journals (Sweden)

    ANDRÉ NASSIF

    2015-09-01

    Full Text Available RESUMOEste artigo analisa o chamado tripé da política macroeconômica brasileira, que desde 1999 tem combinado um regime de metas de inflação, um regime de taxa de câmbio flutuante e metas de superávit fiscal primário. A menos que o seu modus operandi seja alterado, o tripé não será capaz de libertar a economia brasileira de outra "possível trindade": altas taxas de juros reais, a apreciação da taxa de câmbio real e crescimento econômico muito baixo. Depois de analisar brevemente a base teórica sob o tripé macroeconômico, o artigo mostra por que este regime de política macroeconômica, se avaliado numa perspectiva de longo ou médio prazo, não tem sido capaz de garantir a estabilidade dos preços nem o crescimento econômico. Além da sugestão de romper com a estratégia brasileira de crescer com poupança externa, o documento também sugere três principais formas de mudar o modus operandi do tripé brasileiro: i aumentar o horizonte de tempo para atingir a meta de inflação, como tem sido o experiência da maioria dos países que adotam esse regime de política monetária; ii restaurar o papel anticíclico da política fiscal brasileira; e iii adotar uma combinação de mecanismos que visem prevenir que a moeda brasileira entre em uma nova tendência cíclica da apreciação em termos reais.

  17. Revisiting the destination ranking procedure in development of an Intervening Opportunities Model for public transit trip distribution

    Science.gov (United States)

    Nazem, Mohsen; Trépanier, Martin; Morency, Catherine

    2015-01-01

    An Enhanced Intervening Opportunities Model (EIOM) is developed for Public Transit (PT). This is a distribution supply dependent model, with single constraints on trip production for work trips during morning peak hours (6:00 a.m.-9:00 a.m.) within the Island of Montreal, Canada. Different data sets, including the 2008 Origin-Destination (OD) survey of the Greater Montreal Area, the 2006 Census of Canada, GTFS network data, along with the geographical data of the study area, are used. EIOM is a nonlinear model composed of socio-demographics, PT supply data and work location attributes. An enhanced destination ranking procedure is used to calculate the number of spatially cumulative opportunities, the basic variable of EIOM. For comparison, a Basic Intervening Opportunities Model (BIOM) is developed by using the basic destination ranking procedure. The main difference between EIOM and BIOM is in the destination ranking procedure: EIOM considers the maximization of a utility function composed of PT Level Of Service and number of opportunities at the destination, along with the OD trip duration, whereas BIOM is based on a destination ranking derived only from OD trip durations. Analysis confirmed that EIOM is more accurate than BIOM. This study presents a new tool for PT analysts, planners and policy makers to study the potential changes in PT trip patterns due to changes in socio-demographic characteristics, PT supply, and other factors. Also it opens new opportunities for the development of more accurate PT demand models with new emergent data such as smart card validations.

  18. Microstructure–hardness relationship in the fusion zone of TRIP steel welds

    International Nuclear Information System (INIS)

    Nayak, S.S.; Baltazar Hernandez, V.H.; Okita, Y.; Zhou, Y.

    2012-01-01

    Highlights: ► Fusion zone of TRIP steels in resistance spot welding was analyzed. ► Transmission electron microscopy (TEM) was used for characterizing microstructure. ► Fusion zone microstructure was found to depend on the chemistry. ► Hardness values were in accordance with the microstructural constituents in the fusion zone. - Abstract: Fusion zone of three TRIP steels, categorized as AT: C–Mn–Al, AST: C–Mn–Al–Si and ST: C–Mn–Si, in resistance spot welding was characterized with respect to microstructure, phase analysis, and hardness. The fusion zone microstructure was found to depend on chemistry: (i) AT steel contained ferrite phase surrounded by bainite and martensite regions, (ii) AST steel showed a bainite structures along with martensite laths and interlath retained austenite, whereas (iii) ST steel constituted single phase martensite laths with interlath austenite. X-ray diffraction study indicated that retained austenite fraction in the fusion zone increases with increase in Si content in it. The AST fusion zone hardness lies between those of the AT and ST steels; the ST fusion zone hardness was higher than that of AT steel because of the single phase martensite microstructure. Comparison of fusion zone microstructure and hardness to earlier study on laser welding of the TRIP steels with similar chemistries revealed that higher cooling rate in resistance spot welding led to higher fusion zone hardness compared to laser welding; which was attributed either to decrease in softer ferrite phase (AT steel) in the microstructure or refinement of martensite laths (ST steel).

  19. Comparison of results of simulation of the CONTEMPT-LT/028 and lAP-3B codes for the analysis of the internal vacuum breaker valves of the CNLV

    International Nuclear Information System (INIS)

    Ovando C, R.; Cecenas F, M.; Moya C, M.M.

    2006-01-01

    In the primary container of a BWR type reactor, the humid and dry wells its are communicate by means of valves designed to equal the pressure in case of a significant pressure difference exists, produced by an operative event just as the performance of an emergency system. These valves are known as internal vacuum breakers and its analysis it is made by means of the use of a code with the capacity to analyze the primary contention of the reactor. Among the codes able to carry out this analysis type there is CONTEMPT-LT/028 and MAAP-3B; however, these codes possess characteristic different respect the modeling one of the different damage mitigation systems to the contention (dews, windy, emergency systems), of the transfer of heat among the different compartments of the primary container and in the details of the civil construction. In previous works carried out with the CONTEMPT-LT/028 code, they have been carried out different cases of simulation related with the operation of the internal breaker vacuum valves. These cases include small ruptures in the main steam lines and ruptures in the recirculation knots. It was selected the case more restrictive and it was generated an equivalent scenario file for the MAAP-3B code. In this work the performance of the internal breaker vacuum valves is analyzed by means of the CONTEMPT-LT/028 and MAAP-3B codes, when using the case more restrictive consistent in a small rupture in a main steam line. The analysis of the simulations indicates that both codes produce very similar results and the found differences are explained with base in the models used by each code to obtain the answer of the main thermohydraulic variables. In general terms, MAAP-3B possesses models that adapt in a form more convenient to the prospective phenomenology for this analysis, maintaining a conservative focus. (Author)

  20. UNOCAL Parachute Creek Shale Oil Program. Environmental Monitoring Plan - supplemental environmental. Volume 1. Trip 2 report. Rept. for 1988-90

    International Nuclear Information System (INIS)

    1991-01-01

    The Energy Security Act of 1980 established a program to provide financial assistance to private industry in the construction and operation of commercial-scale synthetic fuels plants. The Parachute Creek Shale Oil Program is one of four projects awarded financial assistance. The Program agreed to comply with existing environmental monitoring regulations and to develop an Environmental Monitoring Plan (EMP) incorporating supplemental monitoring in the areas of water, air, solid waste, and worker health and safety during the period 1985-1992. These activities are described in a series of quarterly and annual reports. The report contains results of three years of supplemental environmental sampling (Trial Trip, 1988; Trip 1, 1989; and Trip 2, 1990); Trip 2 sampling and analytical methods; quality assurance and quality control procedures; sampling and analytical methods; and corrected data from 1988 and 1989 gas and particulate concentrations

  1. Implementing virtual field trips in the curriculum of geography students

    Science.gov (United States)

    Steegen, An; Verstraeten, Gert; Martens, Lotte

    2016-04-01

    Current online geospatial databases and tools offer many opportunities in geoscience education. On the one hand a variety of geoscientific topics and regions can be studied without traditional fieldwork, and on the other hand, field-based learning activities can be prepared or post-processed. In this research, the use of Virtual Field Trips (VFTs) in Google EarthTM is studied. In the framework of geomorphology courses, undergraduate geography students were given VFTs as developed by the lecturers or had to develop VFTs themselves, after visiting a study area. Maps, photographs, GPS-tracks, literature and other spatial information were integrated in the VFTs. The effect of VFTs on learning outcomes, on the insight in the horizontal and vertical relationships between the spatially varying topics, and motivation were measured. Results confirm that students are positive about the use of VFTs. They indicate that VFTs significantly improve their mental map of the study area, whereby horizontal relationships were strengthened. Also the additional information in some VFTs proved to have positive effects on studying and structuring the learning content. Students also appreciated to work independently with the VFTs and saw possibilities for integrating various geoscientific topics. However, there are also some constraints in working with VFTs. It was clear from the study that VFTs have to be embedded in the curriculum as students do not use or develop VFTs spontaneously. Indeed, it takes a lot of time to develop a VFT, and students also appreciate a variety in work forms. Also some technical difficulties on sufficient wireless internet access and flexible work spaces have to be encountered. Besides this, curricula developers should be aware that VFTs are an interesting tool additionally to field trips, but that they cannot replace the field trips.

  2. Modeling of the Austenite-Martensite Transformation in Stainless and TRIP Steels

    NARCIS (Netherlands)

    Geijselaers, Hubertus J.M.; Hilkhuijsen, P.; Bor, Teunis Cornelis; Perdahcioglu, Emin Semih; van den Boogaard, Antonius H.; Zhang, S.-H.; Liu, X.-H.; Gheng, M.; Li, J.

    2013-01-01

    The transformation of austenite to martensite is a dominant factor in the description of the constitutive behavior during forming of TRIP assisted steels. To predict this transformation different models are currently available. In this paper the transformation is regarded as a stress induced process

  3. Microstructure Evolution during Friction Stir Spot Welding of TRIP Steel

    DEFF Research Database (Denmark)

    Lomholt, Trine Colding; Pantleon, Karen; Somers, Marcel A. J.

    2010-01-01

    In this study, the feasibility of friction stir spot welding of TRIP steel is investigated. In addition to manufacturing successful welds, the present study aims at a fundamental understanding of the mechanisms occurring at the (sub)micron scale during friction stir spot welding. As one of the ma...... electron microscopy, and electron backscatter diffraction. Microhardness measurements and lap-shear tensile tests completed the investigations of the welded samples and allow evaluation of the quality of the welds.......In this study, the feasibility of friction stir spot welding of TRIP steel is investigated. In addition to manufacturing successful welds, the present study aims at a fundamental understanding of the mechanisms occurring at the (sub)micron scale during friction stir spot welding. As one of the main...... parameters to control friction stir welding, the influence of the rotational speed of the tool was investigated. Three different rotational speeds (500 rpm, 1000 rpm and 1500 rpm, respectively) were applied. The microstructure of the welded samples was investigated with reflected light microscopy, scanning...

  4. Visual exploration of big spatio-temporal urban data: a study of New York City taxi trips.

    Science.gov (United States)

    Ferreira, Nivan; Poco, Jorge; Vo, Huy T; Freire, Juliana; Silva, Cláudio T

    2013-12-01

    As increasing volumes of urban data are captured and become available, new opportunities arise for data-driven analysis that can lead to improvements in the lives of citizens through evidence-based decision making and policies. In this paper, we focus on a particularly important urban data set: taxi trips. Taxis are valuable sensors and information associated with taxi trips can provide unprecedented insight into many different aspects of city life, from economic activity and human behavior to mobility patterns. But analyzing these data presents many challenges. The data are complex, containing geographical and temporal components in addition to multiple variables associated with each trip. Consequently, it is hard to specify exploratory queries and to perform comparative analyses (e.g., compare different regions over time). This problem is compounded due to the size of the data-there are on average 500,000 taxi trips each day in NYC. We propose a new model that allows users to visually query taxi trips. Besides standard analytics queries, the model supports origin-destination queries that enable the study of mobility across the city. We show that this model is able to express a wide range of spatio-temporal queries, and it is also flexible in that not only can queries be composed but also different aggregations and visual representations can be applied, allowing users to explore and compare results. We have built a scalable system that implements this model which supports interactive response times; makes use of an adaptive level-of-detail rendering strategy to generate clutter-free visualization for large results; and shows hidden details to the users in a summary through the use of overlay heat maps. We present a series of case studies motivated by traffic engineers and economists that show how our model and system enable domain experts to perform tasks that were previously unattainable for them.

  5. Personal and Environmental Characteristics Associated with Choice of Active Transport Modes versus Car Use for Different Trip Purposes of Trips up to 7.5 Kilometers in The Netherlands

    NARCIS (Netherlands)

    Scheepers, C.E.; Wendel-Vos, W.; van Kempen, E.; Panis, L.; Maas, J.; Stipdonk, H.; Moerman, M.; den Hertog, F.; Staatsen, B.; van Wesemael, P.; Schuit, A.J.

    2013-01-01

    Introduction:This explorative study examines personal and neighbourhood characteristics associated with short-distance trips made by car, bicycle or walking in order to identify target groups for future interventions.Methods:Data were derived from 'Mobility Research Netherlands (2004-2009; MON)', a

  6. Push-off reactions in recovery after tripping discriminate young subjects, older non-fallers and older fallers.

    Science.gov (United States)

    Pijnappels, Mirjam; Bobbert, Maarten F; van Dieën, Jaap H

    2005-06-01

    Tripping is a major cause for falls, especially in the elderly. This study investigated whether falls in the elderly can be attributed to inadequate push-off reactions by the support limb in the recovery after a trip. Twelve young (20-34 years) and eleven older (65-72 years) men and women walked over a platform and were tripped several times over an obstacle that suddenly appeared from the floor. Kinematics and ground reactions forces of the support limb during push-off were measured of falls and successful recoveries. Young subjects did not fall. The older subjects were divided into a group of four non-fallers and seven fallers. Older fallers showed insufficient reduction of the angular momentum during push-off and less proper placement of the recovery limb. This was due to a lower rate of change of moment generation in all support limb joints and a lower peak ankle moment. Onset of knee moment generation was slightly delayed in older fallers. Improvement over trials was ascribed to better positioning of the recovery limb, as no clear differences were seen in the joint moments of the support limb. In conclusion, the contribution of the support limb to prevent a fall after tripping is decreased in older adults. Lower limb strength could be an underlying factor and strength training might help to reduce fall risk.

  7. Report on safety related occurrences and reactor trips July 1, 1976-December 31, 1976

    International Nuclear Information System (INIS)

    Andermo, L.

    1977-04-01

    This is a systematically arranged report on all reported safety related occurrences and reactor trips in Swedish nuclear power plants in operation during July 1, 1976 to December 31, 1976 inclusive. The facilities involved are Oskarshamn 1 and 2, Ringhals 1 and 2 and Barsebaeck 1. During this period of the 6 months 37 safety related occurrences and 34 reactor trips have been reported to the Nuclear Power Inspectorate. As earlier experiences have shown it is to the greatest extent the conventional components which bring about the safety related occurrences or occurrences leading to outages or power reductions. However, the component errors discovered in the safety related systems have not affected the function of their redundant systems and other diverse systems have not been involved. Therefore the reactor safety has been satisfactory. The fact that even small deviations from prescribed operation results in automatic and safe shut down of the reactor, does not always imply a conflict with operational availability. The number of reactor trips are almost as low as during the last period, which is a drastic reduction compared to earlier time periods. The greatest outages are caused by occurrences without safety significance.(author)

  8. Mikrostruktur udvikling i trip-stål under frictionstir spot svejsning

    DEFF Research Database (Denmark)

    Lomholt, Trine Colding; Pantleon, Karen; Somers, Marcel A. J.

    2010-01-01

    In this work the feasibility of joining TRIP steel by Friction Stir Spot Welding is investigated. The aim is to produce successful welds and to get a fundamental understanding of the mechanisms occurring in the microstructure during welding. One of the primary parameters in Friction Stir Spot...

  9. Inferring High-Resolution Individual’s Activity and Trip Purposes with the Fusion of Social Media, Land Use and Connected Vehicle Trajectories

    Science.gov (United States)

    2017-11-30

    Trip purpose is crucial to travel behavior modeling and travel demand estimation for transportation planning and investment decisions. However, the spatial-temporal complexity of human activities makes the prediction of trip purpose a challenging pro...

  10. NRC Information No. 88-58: Potential problems with ASEA Brown Boveri ITE-51L time-overcurrent relays

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    Several spurious actuations of ASEA Brown Boveri (ABB) ITE-51L relays have occurred at the Beaver Valley nuclear power plant. These actuations resulted in unnecessary interruptions of the electrical power supply to safety-related equipment. The ITE-51L relays monitor circuit current. When the magnitude of the current exceeds a reference value for a specific duration, the relay actuates to energize the circuit breaker's trip coil. The licensee has determined that the spurious relay actuations were caused by faulty silicon-controlled rectifiers (SCRs) that were manufactured by the Motorola Company. SCRs are solid-state devices that are used as electronic switches in electrical circuits. When a voltage is applied across the terminals of the SCR, the device is designed to allow current to flow only when ''gated'' or switched on by the proper electrical signal. The SCRs that failed at Beaver Valley allowed current to flow in the absence of the proper gating signal. These ''leakage'' currents were of sufficient magnitude to energize the trip coil of the associated circuit breaker. The licensee was informed by Motorola that SCRs manufactured between the late 1970s and early 1980s are susceptible to this mode of failure and that these SCRs are likely to fail within the first 2 years of service. Since 1982, all SCRs manufactured by Motorola have been subjected to a ''burn-in'' test. In this test, the SCRs are placed in a high-temperature environment both with and without voltage applied. SCRs that pass this test are expected to perform normally for an extended period

  11. Heat transfer in rotating serpentine passages with trips normal to the flow

    Science.gov (United States)

    Wagner, J. H.; Johnson, B. V.; Graziani, R. A.; Yeh, F. C.

    1991-01-01

    Experiments were conducted to determine the effects of buoyancy and Coriolis forces on heat transfer in turbine blade internal coolant passages. The experiments were conducted with a large scale, multipass, heat transfer model with both radially inward and outward flow. Trip strips on the leading and trailing surfaces of the radial coolant passages were used to produce the rough walls. An analysis of the governing flow equations showed that four parameters influence the heat transfer in rotating passages: coolant-to-wall temperature ratio, Rossby number, Reynolds number, and radius-to-passage hydraulic diameter ratio. The first three of these four parameters were varied over ranges which are typical of advanced gas turbine engine operating conditions. Results were correlated and compared to previous results from stationary and rotating similar models with trip strips. The heat transfer coefficients on surfaces, where the heat increased with rotation and buoyancy, varied by as much as a factor of four. Maximum values of the heat transfer coefficients with high rotation were only slightly above the highest levels obtained with the smooth wall model. The heat transfer coefficients on surfaces, where the heat transfer decreased with rotation, varied by as much as a factor of three due to rotation and buoyancy. It was concluded that both Coriolis and buoyancy effects must be considered in turbine blade cooling designs with trip strips and that the effects of rotation were markedly different depending upon the flow direction.

  12. Monitoring of circuit breakers and detection of rupture cables through the IEDs - intelligent electronic devices; Monitoracao de disjuntor e deteccao de cabos rompidos atraves de IEDs - dispositivos eletronicos inteligentes

    Energy Technology Data Exchange (ETDEWEB)

    Lellys, Denys [Areva T and D Brasil, Sao Paulo, SP (Brazil); Cruz, Jorge; Esteves, Eduardo; Lisboa, Luiz Afonso [Centrais Eletricas do Para (CELPA), Belem, PA (Brazil); Rolim, Joaquim C.; Garrido, Roberto; Silveira, Giordane [Companhia Energetica do Ceara (COELCE), Fortaleza, CE (Brazil)

    2009-04-15

    The advances on digital techniques allowed the inclusion into the modern protection relays, monitoring auxiliary functions of the state of circuit breakers, and the detection of cable rupture, which can reduce the maintenance costs, and increase the operational safety. This article describes in detail those resources, not yet well explored, presenting from the the theoretical base to the practical application and the expected technical and economical results.

  13. DC Fault Analysis and Clearance Solutions of MMC-HVDC Systems

    Directory of Open Access Journals (Sweden)

    Zheng Xu

    2018-04-01

    Full Text Available In this paper, the DC short-circuit fault and corresponding clearance solutions of modular multilevel converter-based high-voltage direct current (MMC-HVDC systems are analyzed in detail. Firstly, the analytical expressions of DC fault currents before and after blocking the MMC are derived based on the operation circuits. Before blocking the MMC, the sub-module (SM capacitor discharge current is the dominant component of the DC fault current. It will reach the blocking threshold value in several milliseconds. After blocking the MMC, the SM capacitor is no longer discharged. Therefore, the fault current from the AC system becomes the dominant component. Meanwhile, three DC fault clearance solutions and the corresponding characteristics are discussed in detail, including tripping AC circuit breaker, adopting the full-bridge MMC and employing the DC circuit breaker. A simulation model of the MMC-HVDC is realized in PSCAD/EMTDC and the results of the proposed analytical expressions are compared with those of the simulation. The results show that the analytical DC fault currents coincide well with the simulation results.

  14. Exploring the role of daily ‘modality styles’ and urban structure in holidays and longer weekend trips

    DEFF Research Database (Denmark)

    Große, Juliane; Olafsson, Anton Stahl; Carstensen, Trine Agervig

    2018-01-01

    comprehensively researched. However, other travel domains (e.g., occasional weekend trips or holidays) have only recently received more attention, despite their environmental impact. The paper investigates whether and how daily travel patterns (‘modality styles’) correspond with non-daily travel behaviour...... in the commuter belt of Greater Copenhagen in spring 2016. First, we identify ‘modality styles’ by grouping the sample based on the respondents’ daily mode choices. Second, we relate the identified modality styles to socio-economic and socio-demographic factors, frequency and mode choice of longer weekend trips...... and holidays, and travel-related attitudes. The results reveal that the urban structure of a residential location (e.g., urban vs. peri-urban) exerts to some extent influence on the constitution of daily modality styles. We found, furthermore, a tendency for more weekend trips and holidays among the urban...

  15. Probing the Evolution of Retained Austenite in TRIP Steel During Strain-Induced Transformation: A Multitechnique Investigation

    Science.gov (United States)

    Haidemenopoulos, G. N.; Constantinou, M.; Kamoutsi, H.; Krizan, D.; Bellas, I.; Koutsokeras, L.; Constantinides, G.

    2018-06-01

    X-ray diffraction analysis, magnetic force microscopy, and the saturation magnetization method have been employed to study the evolution of the percentage and size of retained austenite (RA) particles during strain-induced transformation in a transformation-induced plasticity (TRIP) steel. A low-alloy TRIP-700 steel with nominal composition Fe-0.2C-0.34Si-1.99Mn-1Al (mass%) was subjected to interrupted tensile testing at strain levels of 0-22% and the microstructure subsequently studied. The results of the three experimental techniques were in very good agreement regarding the estimated austenite volume fraction and its evolution with strain. Furthermore, this multitechnique approach revealed that the average particle size of RA reduced as the applied strain was increased, suggesting that larger particles are less stable and more susceptible to strain-induced phase transformation. Such experimentally determined evolution of the austenite size with strain could serve as an input to kinetic models that aim to predict the strain-induced transformation in low-alloy TRIP steels.

  16. Leveraging Field Trips in Higher Education for Local Engagement and Impact: An Example from Guatemala

    Science.gov (United States)

    Riker, J.; Watson, M.; Liu, E. J.; Chigna, G.; Purvis, M.; Naismith, A.

    2016-12-01

    For over ten years, the University of Bristol (U.K.) has run a field trip for masters students in Natural Hazards in the volcanically active areas of southern Guatemala, home to more than 13 million people. This trip has obvious benefits to its participants - it serves as an immersive and formative experience for students studying volcanic hazard, as well as a springboard for the work of the researchers who lead it. Over the years, it has helped to build strong collaborative ties between academic researchers at Bristol and Guatemala's geologic survey (INSIVUMEH) and emergency management agency (CONRED), facilitating the sharing of data, expertise, and monitoring equipment. The students' regular presence has also enabled infrastructure improvements at Fuego Volcano Observatory, which is itself hosted and partly staffed by the residents of Panimache, a small village just a few miles from the volcano's summit. This field trip does raise challenges, however - an influx of foreign students can draw questions from community members for whom the benefits are indirect (i.e., local job creation or infrastructure improvement) or intangible (i.e., incremental contributions to the body of knowledge regarding volcanic hazard). In this presentation, we'll share stories of our experiences of effective community collaboration in Guatemala. In the spirit of discussion, we would also like to explore the opportunities that exist to better utilise this trip, along with the energy and expertise of its participants, to maximise the positive impact on (and resilience of) local communities, particularly those in the small and largely indigenous villages that populate Fuego Volcano's flanks.

  17. Trend analysis of nuclear reactor automatic trip events subjected to operator's human error at United States nuclear power plants

    International Nuclear Information System (INIS)

    Takagawa, Kenichi

    2009-01-01

    Trends in nuclear reactor automatic trip events due to human errors during plant operating mode have been analyzed by extracting 20 events which took place in the United States during the period of seven years from 2002 to 2008, cited in the LERs (Licensee Event Reports) submitted to the US Nuclear Regulatory Commission (NRC). It was shown that the yearly number of events was relatively large before 2005, and thereafter the number decreased. A period of stable operation, in which the yearly number was kept very small, continued for about three years, and then the yearly number turned to increase again. Before 2005, automatic trip events occurred more frequently during periodic inspections or start-up/shut-down operations. The recent trends, however, indicate that trip events became more frequent due to human errors during daily operations. Human errors were mostly caused by the self-conceit and carelessness of operators through the whole period. The before mentioned trends in the yearly number of events might be explained as follows. The decrease in the automatic trip events is attributed to sharing trouble information, leading as a consequence to improvement of the manual and training for the operations which have a higher potential risk of automatic trip. Then, while the period of stable operation continued, some operators came to pay less attention to preventing human errors and not interest in the training, leading to automatic trip events in reality due to miss-operation. From these analyses on trouble experiences in the US, we learnt the followings to prevent the occurrence similar troubles in Japan: Operators should be thoroughly skilled in basic actions to prevent human errors as persons concerned. And it should be further emphasized that they should elaborate by imaging actual plant operations even though the simulator training gives them successful experiences. (author)

  18. Calculation and Simulation Study on Transient Stability of Power System Based on Matlab/Simulink

    Directory of Open Access Journals (Sweden)

    Shi Xiu Feng

    2016-01-01

    Full Text Available The stability of the power system is destroyed, will cause a large number of users power outage, even cause the collapse of the whole system, extremely serious consequences. Based on the analysis in single machine infinite system as an example, when at the f point two phase ground fault occurs, the fault lines on either side of the circuit breaker tripping resection at the same time,respectively by two kinds of calculation and simulation methods of system transient stability analysis, the conclusion are consistent. and the simulation analysis is superior to calculation analysis.

  19. NRC Fact-Finding Task Force report on the ATWS event at Salem Nuclear Generating Station, Unit 1, on February 25, 1983

    International Nuclear Information System (INIS)

    1983-03-01

    An NRC Region I Task Force was established on March 1, 1983 to conduct fact finding and data collection with regard to the circumstances which led to an anticipated transient without scram (ATWS) event at the Public Service Electric and Gas Company's Salem Generating Station, Unit 1 on February 25, 1983. The charter of the Task Force was to determine the factual information pertinent to management and administrative controls which should have ensured proper operation of the reactor trip breakers in the solid state protection system. This report documents the findings of the Task Force along with its conclusions

  20. Arizona Geology Trip - February 25-28, 2008

    Science.gov (United States)

    Thomas, Gretchen A.; Ross, Amy J.

    2008-01-01

    A variety of hardware developers, crew, mission planners, and headquarters personnel traveled to Gila Bend, Arizona, in February 2008 for a CxP Lunar Surface Systems Team geology experience. Participating in this field trip were the CxP Space Suit System (EC5) leads: Thomas (PLSS) and Ross (PGS), who presented the activities and findings learned from being in the field during this KC. As for the design of a new spacesuit system, this allowed the engineers to understand the demands this type of activity will have on NASA's hardware, systems, and planning efforts. The engineers also experienced the methods and tools required for lunar surface activity.

  1. The Search for Braddock's Caldera-Guidebook for Colorado Scientific Society Fall 2008 Field Trip, Never Summer Mountains, Colorado

    Science.gov (United States)

    Cole, James C.; Larson, Ed; Farmer, Lang; Kellogg, Karl S.

    2008-01-01

    The report contains the illustrated guidebook that was used for the fall field trip of the Colorado Scientific Society on September 6-7, 2008. It summarizes new information about the Tertiary geologic history of the northern Front Range and the Never Summer Mountains, particularly the late Oligocene volcanic and intrusive rocks designated the Braddock Peak complex. Minor modifications were made in response to technical reviews by D.J. Lidke and C.A. Ruleman (U.S. Geological Survey) regarding clarity and consistency, and text editing by M.A. Kidd. However, the text remains essentially similar to the guidebook that was circulated to the participants on the Colorado Scientific Society 2008 field trip. Several notes were added following the trip (as indicated) to address developments since the guidebook was written.

  2. Assessment of full power turbine trip start-up test for C. Trillo 1 with RELAP5/MOD2

    International Nuclear Information System (INIS)

    Lozano, M.F.; Moreno, P.; de la Cal, C.; Larrea, E.; Lopez, A.; Santamaria, J.G.; Lopez, E.; Novo, M.

    1993-07-01

    C. Trillo I has developed a model of the plant with RELAP5/MOD2/36.04. This model will be validated against a selected set of start-up tests. One of the transients selected to that aim is the turbine trip, which presents very specific characteristics that make it significantly different from the same transient in other PWRs of different design, the main difference being that the reactor is not tripped: a reduction in primary power is carried out instead. Pre-test calculations were done of the Turbine Trip Test and compared against the actual test. Minor problems in the first model, specially in the Control and Limitation Systems, were identified and post-test calculations had been carried out. The results show a good agreement with data for all the compared variables

  3. Investigation of DC hybrid circuit breaker based on high-speed switch and arc generator

    Science.gov (United States)

    Wu, Yifei; Rong, Mingzhe; Wu, Yi; Yang, Fei; Li, Mei; Zhong, Jianying; Han, Guohui; Niu, Chunping; Hu, Yang

    2015-02-01

    A new design of DC hybrid circuit breaker based on high-speed switch (HSS) and arc generator (AG), which can drastically profit from low heat loss in normal state and fast current breaking under fault state, is presented and analyzed in this paper. AG is designed according to the magnetic pinch effect of liquid metal. By utilizing the arc voltage generated across AG, the fault current is rapidly commutated from HSS into parallel connected branch. As a consequence, the arcless open of HSS is achieved. The post-arc conducting resume time (Δ tc) of AG and the commutation original voltage (Uc), two key factors in the commutation process, are investigated experimentally. Particularly, influences of the liquid metal channel diameter (Φ) of AG, fault current rate of rise (di/dt) and Uc on Δ tc are focused on. Furthermore, a suitable Uc is determined during the current commutation process, aiming at the reliable arcless open of HSS and short breaking time. Finally, the fault current breaking test is carried out for the current peak value of 11.8 kA, and the validity of the design is confirmed by the experimental results.

  4. Investigation of DC hybrid circuit breaker based on high-speed switch and arc generator.

    Science.gov (United States)

    Wu, Yifei; Rong, Mingzhe; Wu, Yi; Yang, Fei; Li, Mei; Zhong, Jianying; Han, Guohui; Niu, Chunping; Hu, Yang

    2015-02-01

    A new design of DC hybrid circuit breaker based on high-speed switch (HSS) and arc generator (AG), which can drastically profit from low heat loss in normal state and fast current breaking under fault state, is presented and analyzed in this paper. AG is designed according to the magnetic pinch effect of liquid metal. By utilizing the arc voltage generated across AG, the fault current is rapidly commutated from HSS into parallel connected branch. As a consequence, the arcless open of HSS is achieved. The post-arc conducting resume time (Δ tc) of AG and the commutation original voltage (Uc), two key factors in the commutation process, are investigated experimentally. Particularly, influences of the liquid metal channel diameter (Φ) of AG, fault current rate of rise (di/dt) and Uc on Δ tc are focused on. Furthermore, a suitable Uc is determined during the current commutation process, aiming at the reliable arcless open of HSS and short breaking time. Finally, the fault current breaking test is carried out for the current peak value of 11.8 kA, and the validity of the design is confirmed by the experimental results.

  5. Trip Generation by Transportation Mode of Private School, Semi-private and Public. Case Study in Merida-Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Quintero Petit, A.M.; Diaz Gallardo, M.I.; Moreno Gonzalez, E.G.

    2016-07-01

    The trip generation model (TGM) is the first step in transportation forecasting, this is useful for estimating travel demand because it can predict travel from or to a particular land use. Typically, the analysis focuses in residential trip generation as a function of the social and economic attributes of households, but nonresidential land use suggests others variables. Travel generator poles such as: Private school, Semi-private and Public, have not been studied in Venezuela. The TGMs that shows the Institute of Transportation Engineers (ITE), EE.UU, are used typically and could be not appropriate. By using stepwise regression and transformation of data, high correlation coefficients and substantial improvements in the variability of data from several schools they were found. The trip generation rates (TGRs) by transportation mode: walking, motorcycle, public transport and cars, can be compared and be included in the Ibero-American Network of travel attractors poles. (Author)

  6. Online transit trip planner for small agencies using Google Transit : final deployment package.

    Science.gov (United States)

    2011-09-01

    Google Transit is a public transportation trip planner that enables travelers to obtain information regarding available transit services between a : given origin and given destination. While transit agencies can publish their service information onto...

  7. The mechanical stability of retained austenite in low-alloyed TRIP steel under shear loading

    Energy Technology Data Exchange (ETDEWEB)

    Blondé, R., E-mail: r.j.p.blonde@tudelft.nl [Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Materials Innovation Institute, Mekelweg 2, 2628 CD Delft (Netherlands); Jimenez-Melero, E., E-mail: enrique.jimenez-melero@manchester.ac.uk [Dalton Cumbrian Facility, The University of Manchester, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3HA (United Kingdom); Zhao, L., E-mail: lie.zhao@tudelft.nl [Materials Innovation Institute, Mekelweg 2, 2628 CD Delft (Netherlands); Department of Materials Science and Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft (Netherlands); Schell, N., E-mail: norbert.schell@hzg.de [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max Planck Strasse 1, 21502 Geesthacht (Germany); Brück, E., E-mail: e.h.bruck@tudelft.nl [Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Zwaag, S. van der, E-mail: s.vanderzwaag@tudelft.nl [Novel Aerospace Materials Group, Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft (Netherlands); Dijk, N.H. van, E-mail: n.h.vandijk@tudelft.nl [Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)

    2014-01-31

    The microstructure evolution during shear loading of a low-alloyed TRIP steel with different amounts of the metastable austenite phase and its equivalent DP grade has been studied by in-situ high-energy X-ray diffraction. A detailed powder diffraction analysis has been performed to probe the austenite-to-martensite transformation by characterizing simultaneously the evolution of the austenite phase fraction and its carbon concentration, the load partitioning between the austenite and the ferritic matrix and the texture evolution of the constituent phases. Our results show that for shear deformation the TRIP effect extends over a significantly wider deformation range than for simple uniaxial loading. A clear increase in average carbon content during the mechanically-induced transformation indicates that austenite grains with a low carbon concentration are least stable during shear loading. The observed texture evolution indicates that under shear loading the orientation dependence of the austenite stability is relatively weak, while it has previously been found that under tensile load the {110}〈001〉 component transforms preferentially. The mechanical stability of retained austenite in TRIP steel is found to be a complex interplay between the interstitial carbon concentration in the austenite, the grain orientation and the load partitioning.

  8. Marketing a destination: Case of CreateTrips and Mexico

    OpenAIRE

    Tiainen, Johanna; Korvenpää, Emmi

    2015-01-01

    This thesis concentrates on Finnish people travelling to Mexico. Firstly, the writers conduct a quantitative research, a questionnaire, that studies Finnish people’s thoughts and presumptions about Mexico. Secondly, they create mobile travel guides of four different destinations. The questionnaire concentrates on the people’s point of view, asking what people think about Mexico, on what kind of trip would they go it they travel there, how long it would last and so on. The questionnaire also h...

  9. Deformation behaviour of TRIP steel monitoring by in-situ neutrondiffraction

    Czech Academy of Sciences Publication Activity Database

    Zrnik, J.; Muránsky, O.; Šittner, Petr; Oliver, E.C.

    2011-01-01

    Roč. 465, č. 1 (2011), s. 390-394 ISSN 1662-9795 R&D Projects: GA ČR GAP107/10/0824; GA ČR GAP108/10/1296; GA AV ČR(CZ) IAA200100627 Institutional research plan: CEZ:AV0Z10100520 Keywords : TRIP steel * austenite conditioning * retained austenite * neutron diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism http://www.scientific.net/KEM

  10. ON PROBABILITY FUNCTION OF TRIP ROUTE CHOICE IN PASSENGER TRANSPORT SYSTEM OF CITIES

    Directory of Open Access Journals (Sweden)

    N. Nefedof

    2014-02-01

    Full Text Available The results of statistical processing of experimental research data in Kharkiv, aimed at determining the relation between the passenger trip choice probability and the actual vehicles waiting time at bus terminals are presented.

  11. Galvannealing of (high-)manganese-alloyed TRIP- and X-IP registered -steel

    Energy Technology Data Exchange (ETDEWEB)

    Blumenau, M. [ThyssenKrupp Steel Europe AG, Bamenohler Strasse 211, D-57402 Finnentrop (Germany); Norden, M. [DOC Dortmunder Oberflaechencentrum GmbH, Eberhardstrasse 12, D-44145 Dortmund (Germany); Friedel, F.; Peters, K. [ThyssenKrupp Steel Europe AG, Kaiser-Wilhelm-Strasse 100, D-47166 Duisburg (Germany)

    2010-12-15

    In this study the influence of Mn on galvannealed coatings of 1.7% Mn-1.5% Al TRIP- and 23% Mn X-IP registered -steels was investigated. It is shown that the external selective oxides like Mn, Al and Si of the TRIP steel which occur after annealing at 800 C for 60 s at a dew point (DP) of -25 C (5% H{sub 2}) hamper the Fe/Zn-reaction during subsequent galvannealing. Preoxidation was beneficially utilized to increase the surface-reactivity of the TRIP steel under the same dew point conditions. The influence of Mn on the steel alloy was investigated by using a 23% Mn containing X-IP registered -steel which was bright annealed at 1100 C for 60 s at DP -50 C (5% H{sub 2}) to obtain a mainly oxide free surface prior to hot dip galvanizing (hdg) and subsequent galvannealing. As well known from the literature Mn alloyed to the liquid zinc melt stabilizes {delta}-phase at lower temperatures by participating in the Fe-Zn-phase reactions, it was expected that the metallic Mn of the X-IP registered -steel increases the Fe/Zn-reactivity in the same manner. The approximation of the effective diffusion coefficient (D{sub eff}(Fe)) during galvannealing was found to be higher than compared to a low alloyed steel reference. Contrary to the expectation no increased Fe/Zn-reaction was found by microscopic investigations. Residual {eta}- and {zeta}-phase fractions prove a hampered Fe/Zn-reaction. As explanation for the observed hampered Fe/Zn-reaction the lower Fe-content of the high-Mn-alloyed X-IP registered -steel was suggested as the dominating factor for galvannealing. (Copyright copyright 2010 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Report on the 1992 study trip on the Weser aboard the laboratory ship 'Max-Pruess' of the Land North-Rhine-Westfalia

    International Nuclear Information System (INIS)

    1993-01-01

    As agreed by the standing committee of the Weser task force ('Arge Weser'), regular trips on the river for taking measurements have been made since 1965. The ninth trip, from May 8th to 14th, 1992 aboard the ''Max Pruess'', a ship equipped with measuring instruments and a laboratory and owned by the Land North-Rhine-Westphalia, was concerned with three areas of investigation: A) the Fulda and Werra estuaries, B) the upper and middle Weser (Hann.-Muenden (km 0.0) to Bremen (km 361.1)), C) the lower Weser (Bremen (km 0.0) to Kolumbuskai (km 67.8)). A uniform water quality longitudinal profile of the Weser was established during this trip by means of chemico-physical and biological tests. While investigations by measuring stations cover a longer period of time, the measurements taken during a voyage reflect a transient condition and complement long-term trend investigations. The voyage also permits to gain an overview of relative changes in the condition of the river at various points of its course. The evaluation of the results of this trip is facilitated by investigations of Arge Weser already carried through for the duration of several years and information obtained by previous trips. (orig./EF) [de

  13. Effects of Ar and He on Microstructures and Properties of Laser Welded 800MPa TRIP Steel

    Directory of Open Access Journals (Sweden)

    Wang Wen-Quan

    2018-01-01

    Full Text Available Fiber laser welding of cold rolled TRIP steel (transformation Induced Plasticity steel sheet with tensile strength of 820MPa and thickness of 1.4mm was carried out using shielding gases Ar and He, respectively. For the same laser power and welding speed, the effects of different shielding gases on penetration and bead section morphologies were investigated. The microstructures and properties of the TRIP steel joints were also studied. The investigation showed that higher penetration and lower porosity could be obtained under shielding gas He using the same laser power and welding speed. The microstructures of the TRIP joint mainly included martensite and retained austenite. But the joint microhardness and tensile strength were higher under the shielding gas He. The tensile strength of the welded joint perpendicular to the weld line was equal to that of the base metal. But the tensile strength of the joint parallel with the weld line was higher than that of the base metal. The plasticity and formability of the welded joint were impaired due to the formation of martensite in the weld metal.

  14. User oriented trajectory search for trip recommendation

    KAUST Repository

    Shang, Shuo

    2012-01-01

    Trajectory sharing and searching have received significant attentions in recent years. In this paper, we propose and investigate a novel problem called User Oriented Trajectory Search (UOTS) for trip recommendation. In contrast to conventional trajectory search by locations (spatial domain only), we consider both spatial and textual domains in the new UOTS query. Given a trajectory data set, the query input contains a set of intended places given by the traveler and a set of textual attributes describing the traveler\\'s preference. If a trajectory is connecting/close to the specified query locations, and the textual attributes of the trajectory are similar to the traveler\\'e preference, it will be recommended to the traveler for reference. This type of queries can bring significant benefits to travelers in many popular applications such as trip planning and recommendation. There are two challenges in the UOTS problem, (i) how to constrain the searching range in two domains and (ii) how to schedule multiple query sources effectively. To overcome the challenges and answer the UOTS query efficiently, a novel collaborative searching approach is developed. Conceptually, the UOTS query processing is conducted in the spatial and textual domains alternately. A pair of upper and lower bounds are devised to constrain the searching range in two domains. In the meantime, a heuristic searching strategy based on priority ranking is adopted for scheduling the multiple query sources, which can further reduce the searching range and enhance the query efficiency notably. Furthermore, the devised collaborative searching approach can be extended to situations where the query locations are ordered. The performance of the proposed UOTS query is verified by extensive experiments based on real and synthetic trajectory data in road networks. © 2012 ACM.

  15. Ablation of TRIP-Br2, a regulator of fat lipolysis, thermogenesis and oxidative metabolism, prevents diet-induced obesity and insulin resistance.

    Science.gov (United States)

    Liew, Chong Wee; Boucher, Jeremie; Cheong, Jit Kong; Vernochet, Cecile; Koh, Ho-Jin; Mallol, Cristina; Townsend, Kristy; Langin, Dominique; Kawamori, Dan; Hu, Jiang; Tseng, Yu-Hua; Hellerstein, Marc K; Farmer, Stephen R; Goodyear, Laurie; Doria, Alessandro; Blüher, Matthias; Hsu, Stephen I-Hong; Kulkarni, Rohit N

    2013-02-01

    Obesity develops as a result of altered energy homeostasis favoring fat storage. Here we describe a new transcription co-regulator for adiposity and energy metabolism, SERTA domain containing 2 (TRIP-Br2, also called SERTAD2). TRIP-Br2-null mice are resistant to obesity and obesity-related insulin resistance. Adipocytes of these knockout mice showed greater stimulated lipolysis secondary to enhanced expression of hormone sensitive lipase (HSL) and β3-adrenergic (Adrb3) receptors. The knockout mice also have higher energy expenditure because of increased adipocyte thermogenesis and oxidative metabolism caused by upregulating key enzymes in their respective processes. Our data show that a cell-cycle transcriptional co-regulator, TRIP-Br2, modulates fat storage through simultaneous regulation of lipolysis, thermogenesis and oxidative metabolism. These data, together with the observation that TRIP-Br2 expression is selectively elevated in visceral fat in obese humans, suggests that this transcriptional co-regulator is a new therapeutic target for counteracting the development of obesity, insulin resistance and hyperlipidemia.

  16. Os supermercados na oferta de alimentos orgânicos: apelando ao estilo de vida ego-trip Supermarkets and the promotion of organics: appealing to ego-trip life-stile

    Directory of Open Access Journals (Sweden)

    Julia S. Guivant

    2003-12-01

    Full Text Available A medida que a produção e o mercado de alimentos orgânicos foram se expandindo durante os anos 90, tanto no contexto internacional quanto no Brasil, os supermercados passaram a ter um papel dominante em relação aos canais alternativos de comercialização.Este artigo pretende contribuir na análise do papel do setor supermercadista na comercialização de produtos orgânicos, fundamentalmente frutas, legumes e verduras (FLV, e nos tipos de consumidor focalizados nas suas estratégias. Para isto, analisamos diversas referências bibliográficas - publicações especializadas no setor supermercadista e relatórios de agências de consultoria internacional, que nos permitam delinear algumas das características das estratégias dos supermercados na comercialização de orgânicos no mundo e no Brasil. Também procuramos, a partir da análise da estratégia dos supermercados, delinear algumas características do perfil dos consumidores. Argumentamos, a partir dos dados acima referenciados, que o consumo crescente de orgânicos nos supermercados é parte de uma demanda mais ampla por alimentos saudáveis que, por sua vez, faz parte de um estilo de vida que tem sido caracterizado como ego-trip, em contraste com o ecológico-trip.As the production and commercialisation of organic food has been expanding since the 90s, both in the international and Brazilian context, supermarkets have assumed a dominant role in relation to alternative markets. This article intends to contribute to the analysis of this role, especially in the commercialisation of fruits, legumes and vegetables (FLV, and to identify the types of consumer that are addressed by their strategies. I use diverse bibliographic references - specialized publications of the retail sector and reports of international consultancy agencies. Through this material it is possible to characterized supermarket strategies in relation to organics in the world and particularly in Brazil. Also, through

  17. Report on safety related occurrences and reactor trips January 1 - June 30, 1985

    International Nuclear Information System (INIS)

    1986-01-01

    This is a systematically arranged report on all safety-related occurrences and reacotr trips in Swedish nuclear power plants in operation during the period from January 1 to June 30 1985. It is based on the reports submitted by the utilities to the Swedish Nuclear power Inspectorate according to Technical Specifications. Twice a year since 1974 the Inspectorate has issued a compilation on such reported occurrences and reactor trips. Starting with the compilation of the second half of 1982 some new features have been introduced. The most important change is that the volume of information has been increased. The full test, provided by the utilities when reporting the incidents, is now attached to the codified information and also the layout has been altered to facilitate reading. As in the previous reports the occurrences and reactor trips are arranged both alphabetically by facility name and chronologically by report number for each facility. Electricity generation charts for each facility are also presented. The primary purpose of this report is thus to present all the information furnished by utlities when they submit their reports according the Technical Specifications. The only evaluation made by the Inspecotrate is the categorization on the incidents. Like the previous reports this one also presents frequency of incidents as related to affected component, cause of incident etc. The difference is that only information reported by the utilities is used. This is the reason why a considerable proportion of the incidents are categorized as 'other fault'. (author)

  18. Multiscale mechanics of TRIP-assisted multiphase steels: I. Characterization and mechanical testing

    International Nuclear Information System (INIS)

    Jacques, P.J.; Furnemont, Q.; Lani, F.; Pardoen, T.; Delannay, F.

    2007-01-01

    The mechanical behaviour of transformation-induced plasticity (TRIP)-assisted multiphase steels is addressed based on three different microstructures generated from the same steel grade. The mechanisms responsible for the work-hardening capacity and the resulting balance between strength and resistance to plastic localization are investigated at different length scales. The macroscopic mechanical response is determined by simple shear, uniaxial tension, Marciniak and equibiaxial tension supplemented by earlier tensile tests on notched and cracked specimens. It is shown that the transformation rate reaches a maximum for stress states intermediate between uniaxial tension and equibiaxial tension. At an intermediate length scale, the true in situ flow properties of the individual ferrite-bainite and retained austenite phases are determined by combining neutron diffraction and digital image correlation. This combined analysis elucidates the partitioning of stress and strain between the different constitutive phases. Based on these results, supplemented by transmission electron microscopy and electron backscattered diffraction observations, a general overview of the hardening behaviour of TRIP-assisted multiphase steels is depicted

  19. Neutron depolarisation study of the austenite grain size in TRIP steels

    International Nuclear Information System (INIS)

    Dijk, N.H. van; Zhao, L.; Rekveldt, M.Th.; Fredrikze, H.; Tegus, O.; Brueck, E.; Sietsma, J.; Zwaag, S. van der

    2004-01-01

    We have performed combined neutron depolarisation and magnetisation measurements in order to obtain an in situ determination of the average grain size and volume fraction of the retained austenite phase in TRIP steels. The average grain size of the retained austenite was found to decrease for an increase in austenite volume fraction at two different annealing temperatures

  20. TRIP: a finite element computer program for the solution of convection heat transfer problems

    International Nuclear Information System (INIS)

    Slagter, W.; Roodbergen, H.A.

    1976-01-01

    The theory and use of the finite element code TRIP are described. The code calculates temperature distributions in three-dimensional continua subjected to convection heat transfer. A variational principle for transport phenomena is applied to solve the convection heat transfer problem with temperature and heat flux boundary conditions. The finite element discretization technique is used to reduce the continuous spatial solution into a finite number of unknowns. The method is developed in detail to determine temperature distributions in coolant passages of fuel rod bundles which are idealized by hexahedral elements. The development of the TRIP code is discussed and the listing of the program is given in FORTRAN IV. An example is given to illustrate the validity and practicality of the method