WorldWideScience

Sample records for breakers resolve trip

  1. Design of the Control Interface of Reactor Trip Breaker in Nuclear Power Plant%核电厂停堆断路器停堆控制接口设计

    Institute of Scientific and Technical Information of China (English)

    周叶翔; 田亚杰; 任立永; 刘光明; 江辉

    2015-01-01

    In PWR nuclear power plants, the reactor trip breakers are commonly used as the actuators of emergency reactor trip system. Through researching and analyzing various existing trip control interface schemes, two hidden dangers in current designing schemes are pointed out, i. e. , the load of the trip coil don' t match with the load capacity of the control platform;and the circuit coupling is existing among control loops of the under voltage coils of trip breakers. To against these two problems, in accordance with related standards and regulations, improving schemes are proposed respectively by using dioxide circuit decoupling method and intermediate relay decoupling method, these provide reference for designing trip control interface of subsequent nuclear power plants.%压水堆核电厂普遍采用停堆断路器作为紧急停堆系统的执行机构. 通过对当前多种停堆控制接口方案的研究分析,指出当前的设计方案在某些工作瞬态下存在两个隐患:停堆线圈的负载与控制平台的带载能力失配;停堆断路器欠压线圈控制回路间存在电路耦合. 针对这两个问题,根据相关标准法规要求,采用二极管电路解耦方法及中间继电器解耦方法,分别提出一种改进方案,为后续核电厂停堆控制接口的设计及改造提供参考.

  2. 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 lay

  3. 330 MW火电机组发变组出口断路器跳闸原因分析%Trip cause analysis for outlet circuit breaker trip of generator-transformer unit in 330 MW coal-fired power plant

    Institute of Scientific and Technical Information of China (English)

    余民

    2015-01-01

    针对一起330 MW火电机组发变组出口断路器在无任何保护动作情况下的跳闸故障,采用逐步排查法,通过现场模拟实验,找出了故障的原因,提出有效解决办法并制定了防范措施.应用结果表明:改进措施消除了机组存在的安全隐患,确保了机组的长周期安全运行.%Aiming at an accident of generator-transformer unit outlet circuit breaker trip without any protection device act in 330 MW coal-fired power plant,using gradual elimination method and field simulation test,finds out the causes of the trip,puts forward effective solution and preventive measures. The application result shows that the improved measures eliminate the hidden safety trouble,guarantee long periodic safe operation of the 330 MW coal-fired power generation unit.

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

    International Nuclear Information System (INIS)

    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

  5. 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.

  6. 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.

  7. Reliability centered maintenance of power transformers and circuit breakers

    Energy Technology Data Exchange (ETDEWEB)

    Purucker, S.L.; Goeltz, R.T. [Oak Ridge National Lab., TN (United States); Hemmelman, K.; Price, R. [Bonneville Power Administration, Van Couver, WA (United States)

    1992-08-01

    At the Bonneville Power Administration (BPA), we have historically maintained high voltage equipment. Including transformers and power circuit breakers, on a time driven basis. While this has served our needs in the past, newer methods are needed to effectively maintain the power system in future years. Today aging equipment, maintenance backlogs, and budget constraints are a reality. BPA has initiated a research and development project to examine reliability centered maintenance (RCM) as an alternative to time based maintenance on high voltage equipment. Under RCM, the performance of each place of equipment is to be monitored by observing many operating parameters. For example, with circuit breakers we will observe (measure) the trip time, accumulated contact wear using I{sup 2}T, timing of the mechanism, plus several other parameters. Equipment performing below a predetermined level, or equipment having accumulated a large amount of ``usage`` will receive maintenance. The maintenance will restore full performance and preserve an acceptable service life for that piece of equipment. To develop and evaluate RCM concepts, BPA is installing a prototype system at our Alvey Substation on 4 transformers and 25 breakers.

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

    International Nuclear Information System (INIS)

    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

  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. Arc modelling in SF6 circuit breakers

    International Nuclear Information System (INIS)

    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)

  11. Experience with the Alpine Breaker Line Support

    Energy Technology Data Exchange (ETDEWEB)

    Habnicht, H.; Halbmayer, C.

    1989-01-01

    The Alpine Breaker Line Support is new, mechanised support equipment for stabilising the caving edge during depillaring operations. A short discussion is presented of some panel geometry variations used, and of performance data achieved. 5 figs.

  12. Causes Analysis, Treatment and Prevention of Remote Switch Refused Action and Tripping Coil Burnout in 110kV Circuit Breaker%110 kV断路器远控分闸开关拒动跳闸线圈烧毁故障原因分析及处理防范

    Institute of Scientific and Technical Information of China (English)

    毛艳东

    2015-01-01

    Through introducing the refused action in breaking the 110kV 161QF remote switch in Dahua hydropower station as well as theoretically analyzing and investigating the reasons of the refused action and the tripping coil burnout, it is found that there is tripping coil burnout risk in the control circuit due to the design defect of switch op-erating mechanism. To eliminate it, some correction measures are presented and brought into operation after passed through on-site inspection.%通过介绍大化水电厂一起远控分闸110 kV 161QF开关过程中出现分闸失灵、开关拒动故障,综合排查故障原因,对跳闸线圈烧毁原因进行详细分析,并通过理论分析, 最后发现开关操作机构设计上存在的缺陷,因操作机构存在的缺陷导致控制回路存在严重隐患,提出整改防范措施,并通过现场检验后投入运行无问题,排除了跳闸线圈烧毁隐患.

  13. A threshold for the Maker-Breaker clique game

    NARCIS (Netherlands)

    Muller, Tobias; Stojakovic, Milos

    2014-01-01

    We study the Maker-Breaker k-clique game played on the edge set of the random graph G(n, p). In this game, two players, Maker and Breaker, alternately claim unclaimed edges of G(n, p), until all the edges are claimed. Maker wins if he claims all the edges of a k-clique; Breaker wins otherwise. We de

  14. 30 CFR 75.904 - Identification of circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Identification of circuit breakers. 75.904 Section 75.904 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... Alternating Current Circuits § 75.904 Identification of circuit breakers. Circuit breakers shall be marked...

  15. 30 CFR 77.904 - Identification of circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Identification of circuit breakers. 77.904... COAL MINES Low- and Medium-Voltage Alternating Current Circuits § 77.904 Identification of circuit breakers. Circuit breakers shall be labeled to show which circuits they control unless identification...

  16. Trade, TRIPS, and pharmaceuticals.

    Science.gov (United States)

    Smith, Richard D; Correa, Carlos; Oh, Cecilia

    2009-02-21

    The World Trade Organization's Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) set global minimum standards for the protection of intellectual property, substantially increasing and expanding intellectual-property rights, and generated clear gains for the pharmaceutical industry and the developed world. The question of whether TRIPS generates gains for developing countries, in the form of increased exports, is addressed in this paper through consideration of the importance of pharmaceuticals in health-care trade, outlining the essential requirements, implications, and issues related to TRIPS, and TRIPS-plus, in which increased restrictions are imposed as part of bilateral free-trade agreements. TRIPS has not generated substantial gains for developing countries, but has further increased pharmaceutical trade in developed countries. The unequal trade between developed and developing countries (ie, exporting and importing high-value patented drugs, respectively) raises the issue of access to medicines, which is exacerbated by TRIPS-plus provisions, although many countries have not even enacted provision for TRIPS flexibilities. Therefore this paper focuses on options that are available to the health community for negotiation to their advantage under TRIPS, and within the presence of TRIPS-plus. PMID:19167054

  17. 46 CFR 169.670 - Circuit breakers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and... for— (a) Inverse time delay; (b) Instantaneous short circuit protection; and (c) Repeated opening...

  18. A Biomes Field Trip.

    Science.gov (United States)

    Leonard, William H.; And Others

    1983-01-01

    Describes a field trip designed to give students opportunities to experience relevant data leading to concepts in biogeography. Suggests that teachers (including college instructors) adapt the areas studied and procedures used to their own locations. Includes a suggested field trip handout. (JN)

  19. Cotton Trip in China

    Institute of Scientific and Technical Information of China (English)

    Wang Ting

    2010-01-01

    @@ During their trip in Beijing,the leadership delegation members,Charles Parker,Harrison Ashley(Vice President of NCC Ginner Services),along with Karin Malmstrom(China Director of CCI)shared a time to accept the interview,giving a general introduction about their China trip and the cotton industry in USA.

  20. 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.

  1. Lake Mason trip report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a summary of the August 31, 1998 trip to Lake Mason to review the hydrology, current conditions, habitat and wildlife. This site visit occurred due...

  2. Large Eddy Simulation for Plunge Breaker and Sediment Suspension

    Institute of Scientific and Technical Information of China (English)

    BAI Yuchuan(白玉川); C.O.NG

    2002-01-01

    Breaking waves are a powerful agent for generating turbulence that plays an important role in many fluid dynamicalprocesses, particularly in the mixing of materials. Breaking waves can dislodge sediment and throw it into suspension,which will then be carried by wave-induced steady current and tidal flow. In order to investigate sediment suspension bybreaking waves, a numerical model based on large-eddy-simulation (LES) is developed. This numerical model can beused to simulate wave breaking and sediment suspension. The model consists of a free-surface model using the surfacemarker method combined with a two-dimensional model that solves the flow equations. The turbulence and the turbulentdiffusion are described by a large-eddy-simulation (LES) method where the large turbulence features are simulated bysolving the flow equations, and a subgrid model represents the small-scale turbulence that is not resolved by the flowmodel. A dynamic eddy viscosity subgrid scale stress model has been used for the present simulation. By applying thismodel to Stokes' wave breaking problem in the surf zone, we find that the model results agree very well with experimentaldata. By use of this model to simulation of the breaking process of a periodic wave, it can be found that the model canreproduce the complicated flow phenomena, especially the plunging breaker. It reflects the dynamic structures of roller orvortex in the plunging breaker, and when the wave breaks, many strong vortex structures will be produced in the innersurf zone where the concentration of suspended sediment can thereby become relatively high.

  3. Video auditing techniques for breaker reject

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, B.M.; Corke, P.I.; O`Brien, G.D.; Waugh, J.M. [CSIRO (Australia). Division of Minerals

    1998-12-31

    Rotary breakers are used by many Australian coal mines to reduce the topsize of run of mine (ROM) coal to a size that can be handled by the processing plant. Coal that does not break to the designated topsize therefore passes out with the rock as breaker rejects. The degree of coal loss can be assessed manually by stop belt auditing of the reject belt, but this method is impractical for long-term monitoring of breaker rejects and breaker performance. Case studies of several open cut coal mines in the Bowen Basin of Central Queensland were made to determine the extent of the problem. The results indicated instances where significant losses did occur, but it was not possible to make an accurate estimate of the total value of the losses. This paper covers work undertaken to develop new auditing techniques for qualitative, quantitative and continuous monitoring of reject belt material which uses relatively low-cost equipment and mature technology. Initial work has concentrated on developing video surveillance techniques suitable for the range of environmental conditions typically encountered in the field. Multi-media methods are being developed for qualitative data presentation, and image analysis techniques are being investigated to extract basic quantitative information from video sequences, such as particle size and shape. Future work includes development of automatic methods using machine vision for 100% on-line inspection. The main attraction of the methodology being adopted is the potential to easily adapt the techniques to diagnostic and control functions. In situations where significant losses occur, this approach could open up many possibilities for reducing coal rejection or allowing its recovery from the rejects stream to improve productivity. 12 refs., 4 figs., 1 tab.

  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. Gas breakers for tokamak OHMIC-heating duty

    International Nuclear Information System (INIS)

    The current interrupting capacity of air blast and SF6 breakers is reviewed for application in tokamak ohmic-heating circuits. Particular attention is paid to generator breakers for their large current interrupting capacity and suitability for ohmic-heating circuits

  6. Automatic Speed Breaker on Time Demand Using Embedded Systems

    Directory of Open Access Journals (Sweden)

    Sanchit Vashistha

    2012-11-01

    Full Text Available The concept of this research work is to have an automatic speed breaker on time demand according to the requirements. Means when there is no need of the speed breaker on the road, it disappears from the road and the road becomes flat and when there is a need then the breaker comes on the road from ground and it starts its working of slowing speed of the vehicles. In implementation of this concept, we use an iron made hemi-cylindrical speed breaker which is capable of rotating itself using control circuitry of embedded systems. So when needed, it comes on the road by rotating itself from flat position and when not needed, it rotates itself again and gets flat and combines with flat road. In the system, real time clock is used to mention the required time for having the speed breaker on road. When time gets started, breaker comes on the road and remains until the countdown gets zero. In the Embedded system’s clock any time and date can be stored on which the speed breaker is required on the road. So this type of speed breaker is useful before any building for which the time is specified for coming in the building and going out from it e.g. schools, any organization etc.

  7. Bitter Happy Trips

    Institute of Scientific and Technical Information of China (English)

    WANGYUN

    2005-01-01

    My husband and I worked in Gyilong County of Tibet for six hard years in the late 1970s. We enjoyed the right of paid visits to see our parents back in the hometown at certain intervals. We were happy about this program, although we often found such trips were somewhat bittersweet.

  8. Analysis to Differences of Miniature Circuit Breakers Between EN and IEC Standard%解析小型断路器EN与IEC标准的差异

    Institute of Scientific and Technical Information of China (English)

    章晓艳

    2012-01-01

      Analysis and comparison were carried out for EN and IEC standard about circuit breakers for over-current protection used for household and similar site──circuit breakers for AC operation (miniature circuit breakers for short), EN 60898-1 and IEC 60898-1. In the aspects of product marking requirements, short-circuit test value quantity, tripping characteristic test of circuit breakers, energy losses clas-sification, this paper gave contents of main differences so as to provide references for related technical personnel.%  对欧盟、IEC 关于家用和类似场所用过电流保护断路器——用于交流的断路器(简称小型断路器)的标准 EN 60898-1、IEC 60898-1进行了分析比较,在产品标志要求、短路试验中试验量、断路器的脱扣特性试验、能耗等级分类等方面给出了主要差异内容,以供相关技术人员进行参考。

  9. Transient Ablation Regime in Circuit Breakers

    Institute of Scientific and Technical Information of China (English)

    Alexandre MARTIN; Jean-Yves TREPANIER; Marcelo REGGIO; GUO Xue-yan

    2007-01-01

    Nozzle wall ablation caused by high temperature electric arcs is studied in the context of high voltage SF6 circuit breakers.The simplified ablation model used in litterature has been updated to take into account the unsteady state of ablation.Ablation rate and velocity are now calculated by a kinetic model using two layers of transition,between the bulk plasma and the ablating wall.The first layer (Knudsen layer),right by the wall,is a kinetic layer of a few mean-free path of thickness.The second layer is collision dominated and makes the transition between the kinetic layer and the plasma bulk.With this new coupled algorithm,it is now possible to calculate the temperature distribution inside the wall,as well as more accurate ablation rates.

  10. Anti-rebound Cushion Device for Hydraulic Breaker

    Institute of Scientific and Technical Information of China (English)

    Zhao Hongqiang

    2005-01-01

    This paper analyzes the phenomenon of rebound impact and its negative influence on the present hydraulic breaker. To get over its shortcomings, a new anti-rebound cushion device has been designed to prevent the phenomenon of rebound impact. A hydraulic cushion is used to absorb the rebound impact energy, which can be released for the next stroke of the hydraulic breaker. Thus, there is little loss of energy, and the efficiency of the impact system can be increased by 5 %. The absorption effect of the hydraulic anti-rebound cushion increases the service life of breaker components by up to twice as long as in the current breaker. A dynamic model and a motion equation of the anti-rebound cushion device are presented, and the optimum frequency and damping ratio are obtained, providing optimum design parameters for the anti-rebound cushion device.

  11. 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.

  12. Evaluation of generator circuit breaker applications / J.F. Fourie.

    OpenAIRE

    Fourie, Johannes Frederick

    2010-01-01

    The use of generator circuit breakers in power stations was investigated and evaluated. A feasibility study to determine if the additional capital cost required, when using a generator circuit breaker in a power station could be justified by the advantages it provides. The background to the study is provided through a technology and literature survey. Included in the technology review and the literature study is information on interruption mediums, the historic developments ...

  13. LARGE EDDY SIMULATION FOR PLUNGING BREAKER WAVE

    Institute of Scientific and Technical Information of China (English)

    Bai Yu-chuan; Wang Zhao-yin

    2003-01-01

    As wave propagates into shallow water, the shoaling effect leads to increase of wave height, and at a certain position, the wave will be breaking. The breaking wave is powerful agents for generating turbulence, which plays an important role in most of the fluid dynamical processes in the surf zone, so a proper numerical model for describing the turbulent effect is needed urgently. A numerical model is set up to simulate the wave breaking process, which consists of a free surface model using the surface marker method and the vertical two-dimensional model that solves the flow equations. The turbulence is described by Large Eddy Simulation (LES) method where the larger turbulent features are simulated by solving the flow equations, and the small-scale turbulence that is represented by a sub-grid model. A dynamic eddy viscosity sub-grid scale stress model has been used for the present simulation. The large eddy simulation model, which we presented in this paper, can be used to study the propagation of a solitary wave in constant water depth and the shoaling of a non-breaking solitary wave on a beach. To track free-surface movements, The TUMMAC method is employed. By applying the model to wave breaking problem in the surf zone, we found that these model results compared very well with experimental data. In addition, this model is able to reproduce the complicated flow phenomena, especially the plunging breaker.

  14. 30 CFR 75.800 - High-voltage circuits; circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 75.800... § 75.800 High-voltage circuits; circuit breakers. High-voltage circuits entering the underground area of any coal mine shall be protected by suitable circuit breakers of adequate interrupting...

  15. A Full Hydro- and Morphodynamic Description of Breaker Bar Development

    DEFF Research Database (Denmark)

    Jacobsen, Niels Gjøl

    The present thesis considers a coupled modelling approach for hydro- and morphodynamics in the surf zone, which is based on a solution to the Reynolds Averaged Navier-Stokes (RANS) equations with a Volume of Fluid (VOF) closure for the surf tracking. The basis for the numerical approach is the su......The present thesis considers a coupled modelling approach for hydro- and morphodynamics in the surf zone, which is based on a solution to the Reynolds Averaged Navier-Stokes (RANS) equations with a Volume of Fluid (VOF) closure for the surf tracking. The basis for the numerical approach...... stress on the crest of the breaker bar, and its migration speed. Additionally, a net onshore current over a breaker bar is considered, where this current mimics the presence of a horizontal circulation cell. The development of the breaker bar is described for different values of the net onshore current...

  16. The return trip effect: Why the return trip often seems to take less time

    OpenAIRE

    van de Ven, N.; van Rijswijk, L.; Roy, M.M.

    2011-01-01

    Three studies confirm the existence of the return trip effect: The return trip often seems shorter than the initial trip, even though the distance traveled and the actual time spent traveling are identical. A pretest shows that people indeed experience a return trip effect regularly, and the effect was found on a bus trip (Study 1), a bicycle trip (Study 2), and when participants watched a video of someone else traveling (Study 3). The return trip effect also existed when another, equidistant...

  17. Fracturing Fluid (Guar Polymer Gel Degradation Study by using Oxidative and Enzyme Breaker

    Directory of Open Access Journals (Sweden)

    Aung Kyaw

    2012-06-01

    Full Text Available Oxidative and enzyme breakers are used in this research project with the main objective to study on the degradation pattern of fracturing fluid (i.e., guar polymer gel as a function of time, temperature and breaker concentration itself. The fracturing fluid used in hydraulic fracturing or frac pack contain a chemical breakers to reduce the viscosity of the fluid intermingled with the proppant. Chemical breakers reduce viscosity of the guar polymer by cleaving the polymer into small-molecular-weight fragments. The reduction of viscosity will facilitate the flow-back of residual polymer providing rapid recovery of polymer from proppant pack. Ineffective breakers or misapplication of breakers can result in screen-outs or flow-back of viscous fluids both of which can significantly decrease the well productivity. Breaker activity of low to medium temperature range oxidative and enzyme breaker systems was evaluated. ViCon NF an oxidative breaker (Halliburton product and GBW 12- CD an enzyme breaker (BJ Services product were used in this research project with the main objective to study on the degradation pattern of fracturing fluid (guar polymer gel as a function of (time, temperature and breaker concentration itself. This study provides focuses on the way to mix the fracturing fluid, compositions of the fracturing fluid and how to conduct the crosslink and break test. Crosslink test indicate the optimum cross-linker concentration to produce good crosslink gel and the break test gave the characteristic of the gel during degradation process and also the break time. Besides relying on the laboratory experiment, information obtained from research on SPE and US Pattern papers were used to make a comparison study on oxidative and enzyme breakers properties. Degradation pattern observed from the break test showed that reduction in gel viscosity depends on time, temperature and breaker concentration. Observations from experiment also revealed that small

  18. 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...

  19. Trip report Rainwater Basin Nebraska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is a summary a trip to Rainwater Basin Wetland Management District in 1991, and focuses on the hydrology and soil habitat types. It is part of the...

  20. 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.

  1. Trip Generation Model Based on Destination Attractiveness

    Institute of Scientific and Technical Information of China (English)

    YAO Liya; GUAN Hongzhi; YAN Hai

    2008-01-01

    Traditional trip generation forecasting methods use unified average trip generation rates to determine trip generation volumes in various traffic zones without considering the individual characteristics of each traffic zone.Therefore,the results can have significant errors.To reduce the forecasting error produced by uniform trip generation rates for different traffic zones,the behavior of each traveler was studied instead of the characteristics of the traffic zone.This paper gives a method for calculating the trip efficiency and the effect of traffic zones combined with a destination selection model based on disaggregate theory for trip generation.Beijing data is used with the trip generation method to predict trip volumes.The results show that the disaggregate model in this paper is more accurate than the traditional method.An analysis of the factors influencing traveler behavior and destination selection shows that the attractiveness of the traffic zone strongly affects the trip generation volume.

  2. Calculation and comparison of circuit breaker parameters in Power World Simulator

    Directory of Open Access Journals (Sweden)

    Kuljinder Kaur,

    2016-01-01

    Full Text Available A circuit breaker has ratings that an engineer uses for their application. These ratings define circuit breaker performance characteristics. A good understanding of Ratings allow the electrical engineer to make a proper comparison of various circuit breaker designs. In this research work, the different ratings of circuit breaker were calculated. The other objective of this work was comparison between ratings of existing circuit breaker and calculated ratings in POWER WORLD SIMULATOR. Further, the impact of time delay in circuit breaker was studied. These calculations were performed for rated current of 400 & 630 Amps. The results performed in POWER WORLD SIMULATOR were shown better and information gained from the analysis can be used for proper relay selection, settings, performances and coordination.

  3. An Overview of Dynamic Contact Resistance Measurement of HV Circuit Breakers

    Science.gov (United States)

    Bhole, A. A.; Gandhare, W. Z.

    2016-06-01

    With the deregulation of the electrical power industry, utilities and service companies are operating in a changing business environment. High voltage circuit breakers are extremely important for the function of modern electric power supply systems. The need to predict the proper function of circuit breaker grew over the years as the transmission networks expanded. The maintenance of circuit breakers deserves special consideration because of their importance for routine switching and for protection of other equipments. Electric transmission system breakups and equipment destruction can occur if a circuit breaker fails to operate because of a lack of preventive maintenance. Dynamic Contact Resistance Measurement (DCRM) is known as an effective technique for assessing the condition of power circuit breakers contacts and operating mechanism. This paper gives a general review about DCRM. It discusses the practical case studies on use of DCRM for condition assessment of high voltage circuit breakers.

  4. Switching Surge Analysis of Vacuum Circuit Breaker using EMTP

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ik Mo; Kim, Ji Hong [Hyundai Heavy Industry, Mechatronics Research Institute (Korea)

    2000-07-01

    The first objective of this study is to set up the switching surge analysis method in motor driving distribution system. The simplified model which can simulate the motor energization and circuit breaker re-ignitions, and each circuit element model is presented in this paper. The second objective is to calculate the quantity of surge over-voltage in real nuclear power station. And the surge suppressing measures are verified on the simulation basis. It is clarified that most cases are not satisfactory to meet the IEEE standard 522-1992 without using surge suppressing measures. In cases that the surge arrester are installed in distribution board at the load side of circuit breaker. The IEEE specification is fully met. (author). 6 refs., 4 figs., 3 tabs.

  5. Learning from a Bike Trip

    Science.gov (United States)

    Koren, Mike

    2009-01-01

    In this article, the author describes a bike trip which marks the culmination of a unit reviewing map-reading capabilities. In seventh grade, students develop various map skills, including cardinal and intermediate directions, how to measure distance on a map using a scale of miles, how to interpret the legend of a map, and how to locate places…

  6. Study on the instantaneous protection reliability of low voltage circuit breakers

    Institute of Scientific and Technical Information of China (English)

    LU Jian-guo; DU Tai-hang; LUO Yan-yan

    2007-01-01

    This paper outlines the significance of enhancing the instantaneous protection reliability of low voltage circuit breakers and describes their main failure modes. The instantaneous failure mechanism of low voltage circuit breakers was analyzed so that measures to improve instantaneous protection reliability can be determined. Furthermore, the theory of the instantaneous characteristics Calibration device for low voltage circuit breakers and the method of eliminating the non-periodic component of test current are given in detail. Finally, the test results are presented.

  7. Investigation of a circuit breaker for the ASDEX fusion experiment at Garching

    International Nuclear Information System (INIS)

    In fusion experiments electric discharges are produced in the plasma by interrupting high currents in the ohmic heating coils using fast and powerful circuit breakers. Thereby high plasma currents are induced which heat the plasma. Results obtained with a standard circuit breaker capable of interrupting 30 kA at 20 kV are reported here. The lifetime of the breaker contacts is investigated. (orig.)

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

    International Nuclear Information System (INIS)

    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)

  9. 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...

  10. Structure design of and experimental research on a two-stage laval foam breaker for foam fluid recycling.

    Science.gov (United States)

    Wang, Jin-song; Cao, Pin-lu; Yin, Kun

    2015-07-01

    Environmental, economical and efficient antifoaming technology is the basis for achievement of foam drilling fluid recycling. The present study designed a novel two-stage laval mechanical foam breaker that primarily uses vacuum generated by Coanda effect and Laval principle to break foam. Numerical simulation results showed that the value and distribution of negative pressure of two-stage laval foam breaker were larger than that of the normal foam breaker. Experimental results showed that foam-breaking efficiency of two-stage laval foam breaker was higher than that of normal foam breaker, when gas-to-liquid ratio and liquid flow rate changed. The foam-breaking efficiency of normal foam breaker decreased rapidly with increasing foam stability, whereas the two-stage laval foam breaker remained unchanged. Foam base fluid would be recycled using two-stage laval foam breaker, which would reduce the foam drilling cost sharply and waste disposals that adverse by affect the environment. PMID:26387358

  11. Virtual Field Geologic Trip System

    Institute of Scientific and Technical Information of China (English)

    Jian Wang; Linfu Xue; Xiaojun Zhou

    2003-01-01

    Virtual Field Geologic Trip System (VFGTS) constructed by the technique of visualization can efficiently present geologic field information and widely used in the field of geologic education. This paper introduces the developing thinking of VFGTS and discusses the main implement processes. Building VFGTS mainly includes systemically gathering of field geological data, the building of virtual geological world, and displaying of virtual geologic world and human-computer interaction.

  12. 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 t

  13. 30 CFR 77.800 - High-voltage circuits; circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 77.800... COAL MINES Surface High-Voltage Distribution § 77.800 High-voltage circuits; circuit breakers. High-voltage circuits supplying power to portable or mobile equipment shall be protected by suitable...

  14. 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 of circuit breakers. 75.601-1 Section 75.601-1 Mineral Resources MINE SAFETY AND HEALTH... Trailing Cables § 75.601-1 Short circuit protection; ratings and settings of circuit breakers....

  15. Development, integration and testing of automated triggering circuit for hybrid DC circuit breaker

    International Nuclear Information System (INIS)

    A novel concept of Hybrid DC circuit breaker having combination of mechanical switch and static switch provides arc-less current commutation into the dump resistor during quench in superconducting magnet operation. The triggering of mechanical and static switches in Hybrid DC breaker can be automatized which can effectively reduce the overall current commutation time of hybrid DC circuit breaker and make the operation independent of opening time of mechanical switch. With this view, a dedicated control circuit (auto-triggering circuit) has been developed which can decide the timing and pulse duration for mechanical switch as well as static switch from the operating parameters. This circuit has been tested with dummy parameters and thereafter integrated with the actual test set up of hybrid DC circuit breaker. This paper deals with the conceptual design of the auto-triggering circuit, its control logic and operation. The test results of Hybrid DC circuit breaker using this circuit have also been discussed. (author)

  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.

    (1993) 173-181 173 Elsevier Science Publishers B.V., Amsterdam 00036-1 Technical note The wave vane a device to measure the breaker angle P. Chandramohan, B.U. Nayak and N.M. Anand National Institute of Oceanography, Goa 403 004, India (Received... of a wave direction recording instrument, a simple device called the wave vane as described here has been developed to measure the breaking wave angle. The changes in the horizontal component of the orbital velocity under a progressive wave govern...

  17. Increasing of Switching Abilities of High Voltage Circuit Breakers

    OpenAIRE

    RUSTEMLI, Sabir

    2015-01-01

    The most effective way of increasing switching abilities of high voltage circuit breakers in energy transmission systems is to influence around zero degree to short circuit currents (Maljkovic Z et al 2000; Gashimov, A.M et al. 2001;Antipov, K.M et al. 1985; Gashimov A.M 1991). For this reason, transformers neutral points should be grounded variously for limitation of asymmetric short circuit currents. But another way for this limitation is grounded of transformers neutral points over non-lin...

  18. WIPP site and vicinity geological field trip

    International Nuclear Information System (INIS)

    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

  19. 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.

  20. Risk analysis and control measures after turbine trip but reactor not trip

    International Nuclear Information System (INIS)

    Based on the work experience, this paper presents the phenomenon and risks that may occur after turbine trip but reactor not trip while full power operation of PWR nuclear power plant, and put forward control measures to discuss. (authors)

  1. Does a satisfying trip result in more future trips with that mode?

    OpenAIRE

    De Vos, Jonas; Schwanen, Tim; Van Acker, Veronique; Witlox, Frank

    2016-01-01

    Previous studies have indicated that travel satisfaction – the experienced emotions during, and cognitive evaluation of, a trip – can be affected by travel mode choice and other trip characteristics. However, as satisfactory trips might improve a person’s attitudes toward the used mode, persons may be more likely to use that same mode for future trips of the same kind. Hence, a cyclical process between travel mode choice and travel satisfaction might occur. In this paper we analyse this proce...

  2. Reflections on a Trip: Two Decades Later

    Science.gov (United States)

    Davis-Berman, Jennifer; Berman, Dene

    2012-01-01

    This article reports on a longitudinal qualitative study that involves the interviews of four adults who participated in one of two 10-day wilderness therapy trips 25 years ago. Using qualitative data collection techniques, we conducted in-depth interviews. Respondents were asked to reflect on their lives, the wilderness therapy trip, and the…

  3. Status of the reactor TRIP in HANARO

    International Nuclear Information System (INIS)

    Unexpected reactor trip in HANARO since the first criticality in February, 1995 was investigated. The total numbers of the reactor trip events were 136 and it was 10.4 cases on average each year. During the early stage of the HANARO operation from 1995 to 1997, unexpected reactor trips were occurred frequently. 67% of the total unexpected reactor trips were occurred in that period, which were 91 cases. That duration was for a power ascension test as one of the reactor performance tests. The unexpected reactor trips were mainly caused by system problems and operators' error. Some cases were caused by electric power failure. The most frequent system problem was originated from fluctuation of the signal of the neutron power measuring system. To prevent the reactor trips by this phenomenon, the circuit of the reactor protection system was changed. Operators' error were occurred by mismatching of the neutron and thermal power, which was caused when the deviation of the neutron and thermal power is larger than 3 MW while the reactor power increases. To reduce reactor operators' error, operational procedure was revised and the operators have been trained with the revised one. That has on effect on reducing unexpected reactor trips dramatically. Reactor trips have been occurred by the class-IV power failure or a few problems of system error but never by operators' error since 2000. (author)

  4. What? A Field Trip on the Playground?

    Science.gov (United States)

    Garbutt, Barb

    1983-01-01

    THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: In this day and age of budget problems, school districts are cutting back on many programs, one of which is field trips. Why worry? There must be dozens of trips that can be made on the playground of your school. Let's look into activities that can be accomplished there. SOIL STUDIES: Have you ever…

  5. The Impact of a Deep-Water Plunging Breaker

    CERN Document Server

    Ikeda, Christine; Brucker, Kyle A; Drazen, David A; Dommermuth, Douglas G; Fu, Thomas; Fullerton, Anne M; Duncan, James H

    2014-01-01

    The impact of a plunging breaking wave (wavelength approximately 1.3m) on a rigidly mounted rigid cube structure (dimension 0.31m) that is partially submerged is explored through experiments and numerical calculations. The experiments are carried out in a wave tank and the breaker is generated with a mechanical wave maker using a dispersive focusing technique. The water-surface profile upstream of the front face of the cube and in its vertical centerplane is measured using a cinematic laser-induced fluorescence technique. The three-dimensional flow in the wave tank is simulated directly using the Numerical Flow Analysis (NFA) code. The experiments and the calculations are used to explore the details of the wave-impact process and, in particular, the formation of the high-speed vertical jet that is found on the front face of the cube under some impact conditions.

  6. Every Speed Breaker Is A Source Of Power

    Directory of Open Access Journals (Sweden)

    N. N. Ghuge,

    2014-03-01

    Full Text Available Electricity in India, is a big problem which is faced by people who reside in the country. Electricity is the form of energy, Electricity is a basic part of nature and it is one of our most widely used forms of energy. We get electricity, which is a secondary energy source, from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources. Before electricity generation began slightly over 100 years ago, we use kerosene lamps, and rooms were warmed by wood-burning or coal burning stoves. Direct current (DC electricity had been used in arc lights for outdoor lighting. In the late-1800s, Nikola Tesla pioneered the generation, transmission, and use of alternating current (AC electricity, which can be transmitted over much greater distances than direct current. Generating electricity by speed breakers is innovative and useful concept. R

  7. Vacuum Dielectric Recovery Characteristics of a Novel Current Limiting Circuit Breaker Base on Artificial Current Zero

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhuangxian; ZHUANG Jinwu; WANG Chen; WU Jin; LIU Luhui

    2012-01-01

    A novel current limiting circuit breaker employs zero current switching method in cutting off DC current, which gives out a reverse impulsive current towards a high speed vacuum interrupter and force the current down to zero. This kind of breaker is simply in structure and can act in a very short time with high current limiting capability, and therefore it has a long electric life and is extremely suitable to be installed in a DC electrical system as a fault orotection utility.

  8. Dedicating Finite Volume Method to Electromagnetic Plasma Modeling: Circuit Breaker Application

    OpenAIRE

    Rondot, Loïc; Mazauric, Vincent; Delannoy, Yves; Meunier, Gérard

    2009-01-01

    For several applications including strong hydrodynamics constraints (like in a circuit breaker), Finite Element solvers are not suitable for fluid dynamical modeling. For these applications, the coupling between the Computational Fluid Dynamics and the electromagnetism modeling is not easy. In this context, a magnetodynamic formulation is developed using the Finite Volume Method to address specific issues in multiphysics involved in circuit breaker modeling. The principles of Finite Volume Me...

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

    OpenAIRE

    Popov, M.; Smeets, RPP René; Sluis, van der, B.J.; Herdt, de, H; Declercq, 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 the prestrikes in the VCB are recorded. The test transformer is a prototype distribution transformer, with installed measuring points along transformer windings in each phase. Voltage oscillations a...

  10. CFD Simulation of Transonic Flow in High-Voltage Circuit Breaker

    OpenAIRE

    Xiangyang Ye; Mahesh Dhotre

    2012-01-01

    A high-voltage circuit breaker is an indispensable piece of equipment in the electric transmission and distribution systems. Transonic flow typically occurs inside breaking chamber during the current interruption, which determines the insulating characteristics of gas. Therefore, accurate compressible flow simulations are required to improve the prediction of the breakdown voltages in various test duties of high-voltage circuit breakers. In this work, investigation of the impact of the solver...

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

    OpenAIRE

    Carmen A. Bulucea; Nikos E. Mastorakis; Doru A. Nicola; Marc A. Rosen; Cornelia A. Bulucea

    2013-01-01

    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 i...

  12. 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

  13. Study of the cost reduction possibilities on the secondary equipment of SION Vacuum Circuit Breaker from Siemens AG

    OpenAIRE

    Gil González, Alba

    2011-01-01

    The aim of this Master Thesis is to make a study of the cost reduction possibilities of the secondary equipment of SION Vacuum Circuit Breaker from Siemens AG. The secondary equipment of a circuit breaker consists of several auxiliary devices –usually electronic- which are necessary for operating and controlling the breaker. Regarding the most important requirements for the new M3 price driven market which are Price reduction and Standard technology, a study on the current situation and...

  14. Trip report : Crescent Lake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This trip report is on a visit to Crescent Lake National Wildlife Refuge on September 20 and 21 2001. Wetlands inspected on the Moore Drainage included Martin,...

  15. 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...

  16. 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...

  17. Lobster Processing and Sales Trip Report Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a federally mandated log which is required to be mailed in to NMFS after a fishing trip. This data set includes lobster processing and sales information...

  18. Scrutinized: The TRIPS Agreement and Public Health

    OpenAIRE

    Subhan, Junaid

    2006-01-01

    SUMMARY The World Trade Organization’s (WTO’s) Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) of 1994 seeks to implement a uniform set of intellectual property protection across member nations to provide greater stability in international economic relations. Critics argue that the TRIPS agreement provides unnecessarily strong protection of intellectual property rights which serves to prevent the ill in developing nations from having access to affordable essential m...

  19. TRIPS and Pharmaceuticals: Implications for India

    OpenAIRE

    S. Mehta, Pradeep

    2012-01-01

    On the post-Uruguay Round world trade scenario, after the accords in agriculture and textiles and clothing, the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPs) is the issue affecting developing countries like India. One of the seven intellectual properties covered under TRIPs is that of patents. It has been the contentious issue for several reasons. India is committed to amend its patent laws by the year 2005 (for technologies previously unprotected in its market). ...

  20. Fault current limiter with solid-state circuit breakers

    Science.gov (United States)

    Bălan, H.; Neamț, L.; Buzdugan, M. I.; Varodi, T.; Pop, E.

    2016-08-01

    Switching of power circuit breakers is an important technical issue, especially at short circuit, since the fault current cause thermal and dynamic stresses, and the power quality worsens. Recently, the development of distributed renewable electricity induces the short circuit protection problematic because the distributed production of electric energy cause the transport networks to lose their radial character and disturbs the protective relays coordination. The modern technologies for power switching uses static fault current limiters, which offers a viable solution to remove the problems caused by large fault currents in the system. An appropriate design of the current limiting device reduces the thermal and dynamic stress and limits the fault current to a low value. The static switches are based on high power semiconductor devices that offer advantages compared to mechanical switches. Using a fault current limiter that minimizes the effect of distributed generation of electricity in a radial network on the co-ordination of protective relays is a solution to this problem in terms of switching speed and lifespan of power switches.

  1. 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. PMID:26587241

  2. Biocompatible circuit-breaker chip for thermal management of biomedical microsystems

    Science.gov (United States)

    Luo, Yi; Dahmardeh, Masoud; Takahata, Kenichi

    2015-05-01

    This paper presents a thermoresponsive micro circuit breaker for biomedical applications specifically targeted at electronic intelligent implants. The circuit breaker is micromachined to have a shape-memory-alloy cantilever actuator as a normally closed temperature-sensitive switch to protect the device of interest from overheating, a critical safety feature for smart implants including those that are electrothermally driven with wireless micro heaters. The device is fabricated in a size of 1.5  ×  2.0  ×  0.46 mm3 using biocompatible materials and a chip-based titanium package, exhibiting a nominal cold-state resistance of 14 Ω. The breaker rapidly enters the full open condition when the chip temperature exceeds 63 °C, temporarily breaking the circuit of interest to lower its temperature until chip temperature drops to 51 °C, at which the breaker closes the circuit to allow current to flow through it again, physically limiting the maximum temperature of the circuit. This functionality is tested in combination with a wireless resonant heater powered by radio-frequency electromagnetic radiation, demonstrating self-regulation of heater temperature. The developed circuit-breaker chip operates in a fully passive manner that removes the need for active sensor and circuitry to achieve temperature regulation in a target device, contributing to the miniaturization of biomedical microsystems including electronic smart implants where thermal management is essential.

  3. Numerical Simulation of the Laval Annular Mechanical Foam Breaker for Foam Drilling

    Directory of Open Access Journals (Sweden)

    Pin Lu Cao

    2013-12-01

    Full Text Available The Computational Fluid Dynamics (CFD code, Fluent, is employed to simulate the flow phenomena inside the annular foam breaker in order to improve its performance. The numerical simulation results show that the value and the distribution of the negative pressure are very important for the annular foam breaker. The design of the Laval nozzle not only can increase the fluid velocity, but also can reduce the pressure value from -30.2 to -50.3 kPa compared with the common annular nozzle foam breaker. In order to improve the range of the internal negative pressure, the two-stage Laval annular foam breaker is designed in this study. The analysis results show the distance between the two annular slit have greatly influence on its performance. There is a small overlap area between the two negative pressure zones generated by the two annular slits. The smaller the value distance is, the larger the overlap zone is. When the value of the distance decreases to 50 mm, the minimum negative pressure can be reduced to approximately -65.5 kPa. Meanwhile, the range of the internal negative pressure is larger than the single Laval annular foam breaker, which is benefit to break foam.

  4. Biocompatible circuit-breaker chip for thermal management of biomedical microsystems

    International Nuclear Information System (INIS)

    This paper presents a thermoresponsive micro circuit breaker for biomedical applications specifically targeted at electronic intelligent implants. The circuit breaker is micromachined to have a shape-memory-alloy cantilever actuator as a normally closed temperature-sensitive switch to protect the device of interest from overheating, a critical safety feature for smart implants including those that are electrothermally driven with wireless micro heaters. The device is fabricated in a size of 1.5  ×  2.0  ×  0.46 mm3 using biocompatible materials and a chip-based titanium package, exhibiting a nominal cold-state resistance of 14 Ω. The breaker rapidly enters the full open condition when the chip temperature exceeds 63 °C, temporarily breaking the circuit of interest to lower its temperature until chip temperature drops to 51 °C, at which the breaker closes the circuit to allow current to flow through it again, physically limiting the maximum temperature of the circuit. This functionality is tested in combination with a wireless resonant heater powered by radio-frequency electromagnetic radiation, demonstrating self-regulation of heater temperature. The developed circuit-breaker chip operates in a fully passive manner that removes the need for active sensor and circuitry to achieve temperature regulation in a target device, contributing to the miniaturization of biomedical microsystems including electronic smart implants where thermal management is essential. (paper)

  5. WWER型核电机组反应堆停堆保护系统设计优化与改造%Design Optimization and Modification of Reactor Trip Protection System of Nuclear Power Unit of WWER

    Institute of Scientific and Technical Information of China (English)

    李伟; 袁屹昆; 徐霞军; 苑伟宇

    2011-01-01

    When carrying out periodic test of nuclear power unit reactor trip protection system, it is necessary to disconnect trip breakers in turn. There are big risks in such kind of periodic tests and many unplanned trip e-vents happened because of malfunction of equipment in reactor trip protection system periodic tests of foreign and domestic nuclear power units under operation, which caused great economic loss. The paper introduces the practical results of design optimization and modification of reactor trip protection system of a nuclear power unit of WWER.%在进行核电机组反应堆停堆保护系统定期试验时,需依次将停堆断路器实体断开,此类定期试验风险较大,国内外运行的核电机组多次发生在反应堆停堆保护系统定期试验过程中由于设备故障导致非计划停堆的事件,造成了较大的经济损失.论文介绍了某WWER核电机组反应堆停堆保护系统设计优化方案及改造的实践成果.

  6. Analysis of cold flow reestablishment time in a circuit breaker nozzle

    Science.gov (United States)

    Leone, S. A.; Nagamatsu, H. T.

    1983-01-01

    The deblocking process in a circuit breaker nozzle is similar to the flow starting process in a shock tunnel, and the computer uses this analogy to solve for the deblocking process by utilizing a diaphragm at the throat of a nozzle. At time equal to zero the diaphragm is broken and the throat area increases with time. It is a rarity to have the area as a function of both time and distance. Experimental data obtained from the RPI calibration shock tunnel are utilized to verify some of the calculated results with the area being a function of distance and the agreement is found to be good. The circuit breaker designer can utilize the computer simulation to estimate the deblocking time, an important parameter in the design of circuit breakers.

  7. CFD Simulation of Transonic Flow in High-Voltage Circuit Breaker

    Directory of Open Access Journals (Sweden)

    Xiangyang Ye

    2012-01-01

    Full Text Available A high-voltage circuit breaker is an indispensable piece of equipment in the electric transmission and distribution systems. Transonic flow typically occurs inside breaking chamber during the current interruption, which determines the insulating characteristics of gas. Therefore, accurate compressible flow simulations are required to improve the prediction of the breakdown voltages in various test duties of high-voltage circuit breakers. In this work, investigation of the impact of the solvers on the prediction capability of the breakdown voltages in capacitive switching is presented. For this purpose, a number of compressible nozzle flow validation cases have been presented. The investigation is then further extended for a real high-voltage circuit breaker geometry. The correlation between the flow prediction accuracy and the breakdown voltage prediction capability is identified.

  8. Design of a New Type of Distribution Valve for Hydraulic Breaker and Analysis of Energy Consumption

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Energy consumed by distribution valves causes an energy loss for the output energy of hydraulic breakers, which has a significant influence on its efficiency. A new type of distribution valve used for hydraulic breakers, designed to reduce energy consumption, is analyzed on the basis of the operating principle and energy loss of the current distribution valve. The new distribution valve adopts a cone valve and the optimization technique of unequal open degree for the valve port. Theoretical calculations and analyses have proven that the new distribution valve can reduce energy loss by 9.0127J, or energy consumption by 31%, during an impact cycle and the efficiency of the hydraulic breaker can be raised by 4.5%. It has the following characteristics: little leakage, little pressure loss and low energy consumption.

  9. Research on The Mechanical State Parameter Extraction Method of High Voltage Circuit Breakers

    Directory of Open Access Journals (Sweden)

    Yang Tianxu

    2013-05-01

    Full Text Available High voltage circuit breakers play an important role in the power system. So it is necessary to implement the state detection of breakers in order to ensure stable and reliable running of the grid. The purpose of state detection is to provide reliable basis of maintenance by extracting mechanical state parameters accurately. This paper mainly focuses on the coil current signal feature extraction algorithm. To settle the problem of too much noise mixed with the current signal and signal distortion, the discrete wavelet transform algorithm is used to extract the coil current signal parameters. This paper also designs the FIR filter to extract stroke and speed parameters from travel-time waveform. The experiments show that the difference between the theoretical results and test results processed by the method in this paper is very small and the test results are able to accurately reflect operation states and mechanical features of high voltage circuit breakers.

  10. 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.

  11. Moisture Sensor for Sulfur Hexafluoride (SF6)-filled Circuit Breakers; FINAL

    International Nuclear Information System (INIS)

    Measurements at ORNL were made on the Kahn moisture sensor which Doble Engineering wants to evaluate for use in SF(sub 6) circuit breakers. Test conducted at ORNL indicate that vacuum conditions, as might be found in SF(sub 6) circuit breakers prior to filling with SF(sub 6), could lead to significant changes in calibration, resulting in erroneous readings of moisture content. Similar effects might also be observed in cases where SF(sub 6) byproducts are present, due the reactivity of some of these byproducts with water

  12. Pressure and Arc Voltage Measurement in a 252 kV SF6 Puffer Circuit Breaker

    Science.gov (United States)

    Zhong, Jianying; Guo, Yujing; Zhang, Hao

    2016-05-01

    The pressure distribution in an arcing chamber is critically important for the SF6 puffer circuit breaker design. In this paper, the pressure variation of four locations in the nozzle was measured by piezoresistive and fiber optical pressure sensors at two current levels of 10 kA and 50 kA. An arc voltage measurement was also taken. The results demonstrate that using either type of sensor with a connecting tube is able to detect the fast pressure variation in circuit breakers, however the possible distortion and delay to the pressure transient caused by the tube need further study.

  13. Pressure and Arc Voltage Measurement in a 252 kV SF6 Puffer Circuit Breaker

    Institute of Scientific and Technical Information of China (English)

    ZHONG Jianying; GUO Yujing; ZHANG Hao

    2016-01-01

    The pressure distribution in an arcing chamber is critically important for the SF6 puffer circuit breaker design.In this paper,the pressure variation of four locations in the nozzle was measured by piezoresistive and fiber optical pressure sensors at two current levels of 10 kA and 50 kA.An arc voltage measurement was also taken.The results demonstrate that using either type of sensor with a connecting tube is able to detect the fast pressure variation in circuit breakers,however the possible distortion and delay to the pressure transient caused by the tube need further study.

  14. NEWS: A trip to CERN

    Science.gov (United States)

    Ellison, A. D.

    2000-07-01

    the canteen. Over lunch we mixed with physicists of many different nationalities and backgrounds. Figure 1 Figure 1. In the afternoon we visited Microcosm, the CERN visitors centre, and the LEP control room and also the SPS. Here the students learned new applications for much of the physics of standing waves and resonance that they had been taught in the classroom. Later that night, we visited a bowling alley where momentum and collision theory were put into practice. The following morning we returned to CERN and visited the large magnet testing facility. Here again physics was brought to life. We saw superconducting magnets being assembled and tested and the students gained a real appreciation of the problems and principles involved. The afternoon was rounded off by a visit to a science museum in Geneva - well worth a visit, as some of us still use some of the apparatus on display. Friday was our last full day so we visited Chamonix in the northern Alps. In the morning, we ascended the Aiguille de Midi - by cable car. Twenty minutes and 3842 m later we emerged into 50 km h-1 winds and -10 °C temperature, not counting the -10 °C wind chill factor. A crisp packet provided an unusual demonstration of the effects of air pressure (figure 2). Figure 2 Figure 2. The views from the summit were very spectacular though a few people experienced mild altitude sickness. That afternoon the party went to the Mer de Glace. Being inside a 3 million year-old structure moving down a mountain at 3 cm per day was an interesting experience, as was a tot of whisky with 3 million year-old water. Once again the local scenery was very photogenic and the click and whirr of cameras was a constant background noise. Saturday morning saw an early start for the long drive home. Most students - and some staff - took the opportunity to catch up on their sleep. Thanks are due to many people without whom the trip would never have taken place. Anne Craige, Stuart Williams

  15. 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.

  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. The TRIP from ULF to ARF.

    Science.gov (United States)

    Collado, Manuel; Serrano, Manuel

    2010-04-13

    ARF is a key activator of p53, and together they form a critical duo for protection against cancer. Previous evidence had recognized the regulatory potential of ubiquitin-mediated degradation of ARF. The recent identification of TRIP12/ULF as a ubiquitin ligase of ARF adds an important missing piece to the ARF/p53 pathway.

  18. No "big trips" for the universe

    CERN Document Server

    Faraoni, V

    2007-01-01

    It has been claimed in several papers that a phantom energy-dominated universe can undergo a ``big trip'', i.e., tunneling through a wormhole that grows faster than the cosmic substratum due to the accretion of phantom energy, and will reappear on the other mouth of the wormhole. We show that such claims are unfounded and contradict the Einstein equations.

  19. 49 CFR 236.834 - Trip.

    Science.gov (United States)

    2010-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.834 Trip. A movement of a locomotive over all or any portion of automatic train stop, train control or cab signal territory between the terminals for that locomotive; a movement in one direction. Cross Reference:...

  20. Press trip of Magic Cities Germany

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正>Germany is the first European country which becomes the legal travel destination for the Chinese. Our reporter has joined a press trip of Magic Cities Germany and harvested amazing impressions of the magic sites of Germany Cities: Hannover, Frankfurt and Stuttgart.

  1. Memorable Experiences of a Science Field Trip.

    Science.gov (United States)

    Knapp, Doug

    2000-01-01

    Attempts to learn more about memorable experiences associated with science field trips by conducting a 1-month and an 18-month evaluation of elementary school students who had participated in an environmental science program at a community park in a Midwestern city. Concludes that students' memories were nonspecific and disassociated from…

  2. Field Trips, Minus the Smelly Bus Ride

    Science.gov (United States)

    Barack, Lauren

    2005-01-01

    As school boards nationwide are forced to wield the budget ax-extracurricular activities are often the first items to go. Sports, art classes, and even field trips are increasingly rare. Still, children are curious--and so some schools are turning to virtual means to take students out of the classroom. This article briefly discusses virtual…

  3. 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 off

  4. Automobile trip to Fish Springs, March 16, 1959

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These memoranda describe trips to Fish Springs National Wildlife Refuge. The purpose of these trips was to access the condition of the land in the Fish Springs area.

  5. Lacreek NWR : Trip report, July 19-21, 1995

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Memorandum to the Lacreek National Wildlife Refuge manager reporting a trip, on July 19-21, 1995, to evaluate wetland and upland management on the refuge. The trip...

  6. Southeast Region Headboat Survey-Trip Estimates by Type

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a summary of the number of trips by vessel/area/month/trip type through time and is a means of gauging headboat fishery effort and compliance through time.

  7. 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 transfo

  8. 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...

  9. 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

    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...

  10. Formation and Development of a Breaker Bar under Regular Waves. Part 1: Model Description and Hydrodynamics

    DEFF Research Database (Denmark)

    Jacobsen, Niels Gjøl; Fredsøe, Jørgen; Hjelmager Jensen, Jacob

    2014-01-01

    -shore sediment transport and morphodynamic response are considered. All simulations are presented for regular waves and for values of the deep-water surf similarity parameter, ζ0, in the range from 0.08 to 1.19, i.e. covering both spilling and plunging breakers. © 2014 Elsevier B.V. All rights reserved....

  11. A study on Main Breaker for Quench Protection of HT—7U Toroidal Superconducting Tokammak

    Institute of Scientific and Technical Information of China (English)

    许留伟; 刘小宁

    2002-01-01

    This paper proposes a quench protection project of HT-7U toroidal superconducting tokamak through a forced commutation analysis of DC circuit breaker(DCCB) paralleling fuse.Based on the requirement of quench protection.Amin parameters are selected.Experimental results demonstrate the validity of this proposed project.

  12. A Study on Main Breaker for Quench Protection of HT-7U Toroidal Superconducting Tokamak

    Institute of Scientific and Technical Information of China (English)

    许留伟; 刘小宁

    2002-01-01

    This paper proposes a quench protection project of HT-7U toroidal superconducting tokamak through a forced commutation analysis of DC circuit breaker (DCCB) paralleling fuse.Based on the requirement of quench protection, main parameters are selected. Experimental results demonstrate the validity of this proposed project.

  13. The Implications of the Use of Parental Choice as a Legal "Circuit Breaker"

    Science.gov (United States)

    Mead, Julie F.; Lewis, Maria M.

    2016-01-01

    This study explores four instances where parental choice has been employed as a legal "circuit breaker": (a) First Amendment Establishment Clause cases related to public funding, (b) Fourteenth Amendment Equal Protection cases regarding race-conscious student assignment, (c) Title IX regulations concerning single-sex education, and (d) a…

  14. Using Virtual Field Trips to Connect Students with University Scientists: Core Elements and Evaluation of zipTrips[TM

    Science.gov (United States)

    Adedokun, Omolola A.; Hetzel, Kristin; Parker, Loran Carleton; Loizzo, Jamie; Burgess, Wilella D.; Robinson, J. Paul

    2012-01-01

    Physical field trips to scientists' work places have been shown to enhance student perceptions of science, scientists and science careers. Although virtual field trips (VFTs) have emerged as viable alternatives (or supplements) to traditional physical fieldtrips, little is known about the potential of virtual field trips to provide the same or…

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

    International Nuclear Information System (INIS)

    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

  16. Westinghouse inadvertent plant trip reduction program

    International Nuclear Information System (INIS)

    During recent years, the nuclear power industry has become increasingly aware of the high average number of inadvertent plant trips experienced by commercial units in the United States versus similar experience in other countries, most strikingly, Japan. The need to address this problem stems from the potential consequences which include lost generating capacity (and lost revenue) for the utility, the cost of replacement power, reductions in component and plant life expectancies (due to cycling), and customer dissatisfaction. Perhaps another, more subtle, concern is the impact these trips have on the general public and the confidence that it has in the maturity of the commercial nuclear power program in the United States. This paper serves two purposes: first, it summarizes the program Westinghouse has established to reduce the frequency of unplanned automatic scrams, and second, it discusses several observations, made during the implementation of this program at different utilities

  17. Numerical Simulation of Gas Flow During Arcing Process for 252 kV Puffer Circuit Breakers%Numerical Simulation of Gas Flow During Arcing Process for 252 kV Puffer Circuit Breakers

    Institute of Scientific and Technical Information of China (English)

    吴军辉; 王小华; 马志瀛; 荣命哲; 闫静

    2011-01-01

    A numerical simulation model for 252 kV puffer circuit breaker is constructed, by using a proven commercial computational fluid dynamics (CFD) package, PHOENICS. The model takes into account the moving parts in the circuit breaker, turbulence enhanced momentum and energy transport, radiation transport. The arcing process in a SF6 puffer circuit breaker with two hollow contacts is simulated under different conditions, and the simulation results are verified with experimental results. Through simulation, the pressure, temperature and velocity in the arc quenching chamber can be obtained. The simulation model is also capable of predicting the influence of design parameters variations on breaker performance, and can thus help to reduce the number of short-circuit tests during the design stage.

  18. Analysis of reactor coolant pump trip

    International Nuclear Information System (INIS)

    The trip of one reactor coolant pump accident is simulated with using the IAEA-developed WWER-1000 simulation computer software (IAEA-Code) in this article. The results are compared with the information presented for Bushehr Nuclear Power Plant for the same scenario (analyzed by the code Dynamika-97). The obtained results are compatible with the Bushehr Nuclear Power Plant's given data and show a good overall agreement between them

  19. Trip by Colonel and Mrs Hebbert. 1943

    OpenAIRE

    Hebbert, Henry Eric, 1893-1980, Colonel

    2004-01-01

    229 x 186 mm. A hand-drawn map showing the route of the Hebberts' trip through Eritrea to Ethiopia from Khartoum in 1943. In addition to the map, drawn in blue ink, there are annotations in black ink which read: 'Car Mileage Kh-Kh [presumably Khartoum-Khartoum] 3900 miles' and 'Chain dotted generally by car 3900 mile + By Mule (a) Semiam Mts [presumably Simen Mountains] (b) Lalibela'.

  20. 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.

  1. Advanced Tourist Trip Planning Using Hybrid Recommender

    OpenAIRE

    Saso KOCESKI; Petrevska, Biljana

    2013-01-01

    The paper intends to underline that tourists’ and travelers’ behaviour and preferences have changed dramatically specifically in the way how they search for information. In order to create a tailor-made itinerary and enhance the way of planning a tourist trip, the paper suggests introduction of tourism recommendation systems. For this purpose, a methodology is proposed that assists all interested parties in planning their vacation in more intelligent and sophisticated way by generating a pers...

  2. 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.

  3. Microstructural Development during Welding of TRIP steels

    OpenAIRE

    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 offers a high strength and toughness combination with excellent uniform elongation. However, the higher alloying content of these steel limits their weldability and the thermal cycle of a welding proc...

  4. Scrutinized: the TRIPS agreement and public health.

    Science.gov (United States)

    Subhan, Junaid

    2006-07-01

    The World Trade Organization's (WTO's) Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) of 1994 seeks to implement a uniform set of intellectual property protection across member nations to provide greater stability in international economic relations. Critics argue that the TRIPS agreement provides unnecessarily strong protection of intellectual property rights which serves to prevent the ill in developing nations from having access to affordable essential medications. The first recommendation that this paper makes is to provide two sets of intellectual property protection, one that applies to essential medications such as AIDS drugs and certain antibiotics and another that applies to drugs that treat non-life threatening conditions. The second recommendation builds upon the first recommendation: if two sets of intellectual property protection legislation are enacted, patents on essential medications should be restricted to patents on processes rather than the product itself. The third recommendation seeks to amend the language of the TRIPS agreement to make it obligatory for member nations to implement provisions on compulsory licensing within their domestic legislation. PMID:18523624

  5. 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

  6. Mechanical Fault Diagnosis for HV Circuit Breakers Based on Ensemble Empirical Mode Decomposition Energy Entropy and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Jianfeng Zhang

    2015-01-01

    Full Text Available During the operation process of the high voltage circuit breaker, the changes of vibration signals can reflect the machinery states of the circuit breaker. The extraction of the vibration signal feature will directly influence the accuracy and practicability of fault diagnosis. This paper presents an extraction method based on ensemble empirical mode decomposition (EEMD. Firstly, the original vibration signals are decomposed into a finite number of stationary intrinsic mode functions (IMFs. Secondly, calculating the envelope of each IMF and separating the envelope by equal-time segment and then forming equal-time segment energy entropy to reflect the change of vibration signal are performed. At last, the energy entropies could serve as input vectors of support vector machine (SVM to identify the working state and fault pattern of the circuit breaker. Practical examples show that this diagnosis approach can identify effectively fault patterns of HV circuit breaker.

  7. Stainless steels with trip/twip/sbip effect; Nichtrostende Staehle mit TRIP/TWIP/SBIP-Effekt

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, A.; Gutte, H.; Jahn, A.; Scheller, P.R. [Institut fuer Eisen- und Stahltechnologie, TU Bergakademie Freiberg (Germany)

    2009-08-15

    Economic austenitic steels with high energy absorption capability are in the focus of worldwide research activities, whereby the steels which show TRIP, TWIP and/or SBIP effects play a crucial role. New austenitic or austenitic-martensitic stainless steels with a high cold workability and energy absorption capability are currently developed and tested in laboratory scale at the Institute of Iron and Steel Technology at the Technical University Bergakademie Freiberg. The mechanical properties of these steels are essentially influenced by the TRIP, TWIP and SBIP effect, becoming evident in hot formed and solution annealed steels as well as in as-cast steels. The TRIP/TWIP/SBIP effects have a significant impact on the toughness and the strength of stainless steels consisting of metastable austenite. The TRIP effect owns a paramount position since it serves for a simultaneous increase of toughness and strength. The influences of alloying elements like manganese or nickel on the TRIP effect are in the centre of the investigations at the Institute of Iron and Steel Technology. These austenitic or austenitc-martensitic stainless steels provide the ability for new applications fields due to their excellent mechanical properties. Exemplary, in the Collaborative Research Centre SFB 799 ''TRIP-Matrix-Composites'', financed through the Deutsche Forschungsgemeinschaft DFG, the suitability of this new class of steels for cast components in ductile and transformation strengthened high performance (metal) ceramic composite materials will be investigated. (Abstract Copyright [2009], Wiley Periodicals, Inc.) [German] Weltweit verstaerken sich die Bemuehungen bei der Suche nach kostenguenstigen austenitischen Stahlgueten mit hohem Energieabsorptionsvermoegen. Dabei zeichnen sich verschiedene Forschungsrichtungen ab, die sich auf Staehle mit TRIP-, TWIP- und SBIP-Effekt{sup 1} oder entsprechenden Kombinationen konzentrieren. Am Institut fuer Eisen- und

  8. Research on the overload protection reliability of moulded case circuit-breakers and its test device

    Institute of Scientific and Technical Information of China (English)

    LI Kui; LU Jian-guo; WU Yi; QIN Zhi-jun; YAO Dong-mei

    2007-01-01

    This paper analyzed the reliability and put forward the reliability index of overload protection for moulded case circuit breaker. The success rate was adopted as its reliability index of overload protection. Based on the reliability index and the reliability level, the reliability examination plan was analyzed and a test device for the overload protection of moulded case circuit-breaker was developed. In the reliability test of overload protection, two power sources were used, which reduced the time of conversion and regulation between two different test currents in the overload protection test, which made the characteristic test more accurate. The test device was designed on the base of a Windows system, which made its operation simple and friendly.

  9. Lagrangian kinematics of steep waves up to the inception of a spilling breaker

    CERN Document Server

    Shemer, Lev

    2013-01-01

    Horizontal Lagrangian velocities and accelerations at the surface of steep water-waves are studied by Particle Tracking Velocimetry (PTV) for gradually increasing crest heights up to the inception of a spilling breaker. Localized steep waves are excited using wavemaker-generated Peregrine breather-type wave trains. Actual crest and phase velocities are estimated from video recorded sequences of the instantaneous wave shape as well as from surface elevation measurements by wave gauges. Effects of nonlinearity and spectral width on phase velocity, as well as relation between the phase velocity and crest propagation speed are discussed. The inception of a spilling breaker is associated with the horizontal velocity of water particles at the crest attaining that of the crest, thus confirming the kinematic criterion for inception of breaking.

  10. Online Monitoring System Design of Intelligent Circuit Breaker Based on DSP and ARM

    Directory of Open Access Journals (Sweden)

    Meng Song

    2014-08-01

    Full Text Available In order to accurately analyze the dynamic characteristics of the vacuum circuit breaker, a dual-core master-slave processor structure for online monitoring system based on DSP and ARM is proposed. This structure consists of host computer, lower computer and signal processing modules. The lower computer uses DSP as the core, which completes acquisition and data preprocessing of circuit breaker’s dynamic characteristics through sensors and signal conditioning circuits. The host computer uses ARM as the core which is responsible for task management, analysis, processing and displaying collected data via Ethernet. The communication between DSP and ARM is conducted by HPI. This design improves the reliability of intelligent control unit for the circuit breaker. The experiment showed that this system works steadily and accuracy.

  11. Transient simulation of nozzle geometry change during ablation in high-voltage circuit breakers

    International Nuclear Information System (INIS)

    In high voltage circuit breakers, radiated heat from the electric arc is strongly absorbed by surrounding poly-tetra-fluro-ethylene (PTFE) parts and causes them to reach their vaporization temperature and ablate. Ablation deforms the PTFE parts, widens the throat and hence, changes the nozzle geometry. This paper presents a physical model coupling plasma flow simulation with erosion and movement of the PTFE walls to study this phenomena. The model is first applied and validated on a segmented tube case and on a model SF6 circuit breaker for which the experimental data is available. Then, the model is used to investigate the effect of the surface ablation on the nozzle geometry in a long-operation time. (paper)

  12. Dynamic Simulation and Opening Bouncing Analysis of Vacuum Circuit Breaker with Permanent Magnetic Actuator

    Institute of Scientific and Technical Information of China (English)

    LIN Xin; CAO Chen; LI Bin; LIU Yang; XU Jianyuan

    2013-01-01

    In order to research the dynamic characteristics of circuit breaker (CB) in opening process,taking a 12 kV vacuum circuit breaker (VCB) with permanent magnetic actuator as the example,a dynamic model of the VCB is established based on the virtual prototype technology,and dynamic equations of the model are deduced.Simulation and experiment are carried out on the VCB of both opening and closing processes.The simulative opening time and closing time are 39.5 ms and 54.6 ms respectively.Influencing factors of opening bouncing and their effect principles are analyzed through dynamic simulations of opening bouncing process.Analytic results indicate that the increase in the stiffness coefficient of contact spring limits the opening bouncing; meanwhile increases in the preload of contact spring and the mass of shaft can enlarge the opening bouncing.

  13. 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.

  14. 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.

  15. Cross-shore redistribution of nourished sand near a breaker bar

    DEFF Research Database (Denmark)

    Jacobsen, Niels Gjøl; Fredsøe, Jørgen

    2014-01-01

    This paper focuses on the optimal location for dumping nourished sand on a barred coastline. This is done by investigating the short-term behavior of the cross-shore redistribution of nourished sediment on a breaker-bar profile in a two-dimensional vertical plane. This is achieved by the use of a...... bar can have both destructive and protective impacts on the original shoreward-located cross-shore profile....

  16. IMPROVEMENT OF TRANSIENT STABILITY OF POWER SYSTEM USING SOLID STATE CIRCUIT BREAKER

    OpenAIRE

    Kalai Murugan Amirthalingam; Raja Prabu Ramachandran

    2013-01-01

    The aim of this study is to use a solid state circuit breaker for the improvement of transient stability margin. Long distance AC transmission is often subject to stability problems, which limits the transmission capability. Interconnected power systems suffer from weakly damped swings between synchronous generator and sub systems. The development of modern power system has lead to an increasing complexity in the study of power system and also presents new challenges to power system stability...

  17. 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.

  18. 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

  19. Microstructure Evolution during Friction Stir Spot Welding of TRIP steel

    OpenAIRE

    Lomholt, Trine Colding; Somers, Marcel A. J.; da Silva Fanta, Alice Bastos; Pantleon, Karen

    2013-01-01

    TRansformation Induced Plasticity (TRIP) stål er udviklet til anvendelse i bilindustrien på grund af den fremragende kombination af høj styrke og formbarhed. Mikrostrukturen af TRIP stål er en kompleks blanding af mange mikrostruktur-dele: ferrit, bainit, martensit og austenit. TRIP effekten er aktiveret under indflydelse af ekstern mekanisk belastning, der fører til en martensitisk transformation af austenit. Martensit-dannelsen under deformation bidrager til de fremragende mekaniske egenska...

  20. 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.

  1. Hydrodynamic characteristics and geometric properties of plunging and spilling breakers over impermeable slopes

    Science.gov (United States)

    Alagan Chella, Mayilvahanan; Bihs, Hans; Myrhaug, Dag; Muskulus, Michael

    2016-07-01

    The two-phase flow CFD model REEF3D has been used for modeling waves breaking over a sloping seabed for a spilling and a plunging breaker. This model is based on Reynolds-averaged Navier-Stokes (RANS) equations with the level set method (LSM) for the free surface and k-ω model for turbulence. First, the characteristics and geometric properties of plunging breaking waves with different offshore wave steepnesses over slopes are examined and discussed. The study further explores the hydrodynamic characteristics of spilling and plunging breakers in terms of the wave height evolution and attenuation, horizontal and vertical velocity, free surface profile evolution, and the geometric properties during the development of the breaking process. The numerical results show a good agreement with experimental data in terms of free surface elevation, horizontal and vertical velocity, wave envelope and turbulent intensity for the spilling and plunging breakers. Results of numerical simulations describing the physical flow characteristics such as the formation of the forward overturning water jet, air pocket, splash-up, and the secondary wave during the breaking process are presented for both cases. For both cases, the physical flow process is found to have similar flow features, but the breaking process occurs at significantly different scales.

  2. 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.

  3. The Danish Curve Breaker Agreement model - a voluntary agreement to break the electricity consumption curve

    Energy Technology Data Exchange (ETDEWEB)

    Jarby, Christian (Public Sector Affairs, The Danish Electricity Saving Trust (Denmark)); Pagh Nielsen, Karen Marie (Alectia A/S (Denmark)); Fjordbak, Troels (IT Energy ApS (Denmark))

    2009-07-01

    Both the public and private company sectors are continually acquiring more electrically powered equipment. Consequently, electricity consumption has risen by more than 1% per year over the last 10 years in Denmark (Danish Energy Agency, 2008). Curve Breaker Agreements were introduced in Denmark in 2007 by The Danish Electricity Saving Trust, an independent institution led by a Board appointed by the Danish Ministry of Climate and Energy. The agreements commit organisations and companies signing the agreements to reduce their electricity consumption and 'break the rising electricity curve', typically over a 3-year period. This paper describes the Curve Breaker Agreement model and analyses the effectiveness of initiatives and solutions in different agreements. The analysis is based on empirical research covering 115 agreements concluded by 18 March 2009. The research also includes remotely metered electricity consumption data and interviews with agreeing partners. The results showed that agreements should be concluded at macro level. An important precondition of the agreement follow-up process is that both parties should be able to track the electricity consumption of an individual organisation on a website. 115 agreements have been concluded in about 2 years, and by December 2008 the list of signatories included one third of all Danish municipalities, government ministries and public sector institutions, as well as a number of large private companies. The latest survey of electricity consumption in the Danish public sector indicates that the consumption curve by signatories of Curve Breaker Agreements has generally been broken, and is heading lower.

  4. IMPROVEMENT OF TRANSIENT STABILITY OF POWER SYSTEM USING SOLID STATE CIRCUIT BREAKER

    Directory of Open Access Journals (Sweden)

    Kalai Murugan Amirthalingam

    2013-01-01

    Full Text Available The aim of this study is to use a solid state circuit breaker for the improvement of transient stability margin. Long distance AC transmission is often subject to stability problems, which limits the transmission capability. Interconnected power systems suffer from weakly damped swings between synchronous generator and sub systems. The development of modern power system has lead to an increasing complexity in the study of power system and also presents new challenges to power system stability and in particular to the aspects of transient stability and small signal stability. Transient stability control plays a significant role in ensuring the stable operation of power systems in the event of large disturbances and faults and is thus a significant area of research. This study investigates the improvement of transient stability of a two area system, using Solid State Circuit Breaker which is capable of fast switching in case of faults and thus controlling the real and reactive power flows in a faulted transmission line. Simulations are carried out in Matlab/Simulink environment for two area system model with Solid State Circuit Breaker to analyze the effects of SSCB on transient stability performance of the system. From the simulation results, swing curves of the three phase faulted power system without SSCB gets increases monotonically and thus the system can be considered as unstable whereas the swing curves of the system with an SSCB reaches to a steady state.

  5. Trip Oriented Search on Activity Tra jectory

    Institute of Scientific and Technical Information of China (English)

    陈伟; 赵雷; 许佳捷; 刘冠锋; 郑凯; 周晓方

    2015-01-01

    Driven by the flourish of location-based services, trajectory search has received significant attentions in recent years. Different from existing studies that focus on searching trajectories with spatio-temporal information and text de-scriptions, we study a novel problem of searching trajectories with spatial distance, activities, and rating scores. Given a query q with a threshold of distance, a set of activities, a start point S and a destination E, trip oriented search on activity trajectory (TOSAT) returns k trajectories that can cover the activities with the highest rating scores within the threshold of distance. In addition, we extend the query with an order, i.e., order-sensitive trip oriented search on activity trajectory (OTOSAT), which takes both the order of activities in a query q and the order of trajectories into consideration. It is very challenging to answer TOSAT and OTOSAT efficiently due to the structural complexity of trajectory data with rating infor-mation. In order to tackle the problem efficiently, we develop a hybrid index AC-tree to organize trajectories. Moreover, the optimized variant RAC+-tree and novel algorithms are introduced with the goal of achieving higher performance. Extensive experiments based on real trajectory datasets demonstrate that the proposed index structures and algorithms are capable of achieving high efficiency and scalability.

  6. The "Science" Behind a Successful Field Trip to the Zoo

    Science.gov (United States)

    Scott, Catherine Marie; Matthews, Catherine E.

    2011-01-01

    A field trip to the local zoo is often a staple in many elementary school curricula. Many zoos offer free entry to local teachers and their students. Teachers take students on field trips to enrich the curriculum, make connections to what students are learning in school, and provide students with meaningful learning experiences (Kisiel 2007).…

  7. Gezocht: de beste roofmijt voor Californische trips in roos

    NARCIS (Netherlands)

    Arkesteijn, M.; Pijnakker, J.

    2012-01-01

    De Californische trips, Frankliniella occidentalis, is een van de belangrijkste plagen in de glastuinbouw. De introductie van deze trips dateert van 1984. Het plaaginsect vormt nu een struikelblok voor de verdere uitbreiding van geïntegreerde bestrijding. In roos kan een klein aantal van deze tripse

  8. The Beginner's Guide to Interactive Virtual Field Trips

    Science.gov (United States)

    Zanetis, Jan

    2010-01-01

    For students, field trips can be the best of both worlds: a welcome and exciting break from day-to-day classroom activities and a memorable, real-world experience that will solidify the curriculum in their minds. Unfortunately, the most desirable trips--those to far-away, enticing destinations--have long been inaccessible to all but a select few,…

  9. Psychological Sense of Community and Group Cohesion on Wilderness Trips

    Science.gov (United States)

    Breunig, Mary; O'Connell, Tim; Todd, Sharon; Young, Anderson; Anderson, Lynn; Anderson, Dale

    2008-01-01

    A primary purpose of many wilderness trip programs is the development of positive interpersonal relationships and group experiences that lead to enhanced sense of community among group members. Although there is anecdotal evidence to support the development of sense of community on wilderness trips, there is little empirical evidence to support…

  10. Safety aspects of unplanned shutdowns and trips

    International Nuclear Information System (INIS)

    The issue of unplanned shutdowns and trips is receiving increased attention worldwide in view of its importance to plant safety and availability. There exists significant variation in the number of forced shutdowns for nuclear power plants of the same type operating worldwide. The reduction of the frequency of these events will have safety benefits in terms of reducing the frequency of plant transients and the challenges to the safety systems, and the risks of possible incidents. This report provides an insight into the causes of unplanned shutdowns experienced in operating nuclear power plants worldwide, the good practices that have been found effective in minimizing their occurrence, and the measures that have been taken to reduce these events. Specific information on the experiences, approaches and practices of some countries in dealing with this issue is presented in Appendix A

  11. Development and formability analysis of TRIP seamless steel tube

    Institute of Scientific and Technical Information of China (English)

    Zhang Zicheng; Zhu Fuxian

    2014-01-01

    In this paper, the production technology of transformation induced plasticity (TRIP) steel was first introduced into the steel tube manufacture field to produce the steel tubes with high strength and plasticity. The TRIP seamless steel tubes with the microstructure of ferrite, bainite, retained austenite and a little martensite were successfully fabricated using a cold-drawn steel tube with two-stage heat treatment technique and continu- ous heat treatment process, respectively. The ring tensile test and cold bend test were carried out to study the formability of the newly developed TRIP seamless steel tube. The results showed that the TRIP seamless steel tubes have a good cold formability, and they are available to be used in the tube hydroforming process. In ad- dition, the equipment of continuous heat treatment developed in the current study can be used to produce TRIP steel tube, and it may serve as an important reference for the industrial production of TRIP steel tube.

  12. 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.

  13. 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...... 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...

  14. 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....... 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...

  15. El uso de los "ice breakers" en la orientación de las asignaturas

    OpenAIRE

    Galván Vallina, Joaquín; Gutiérrez Duarte, María Victoria

    2012-01-01

    El proceso de renovación pedagógica que ha supuesto el Espacio Europeo de Educación Superior (EEES) conduce a una nueva orientación en el desarrollo de las asignaturas. Con arreglo a estos planteamientos, se ha desarrollado el uso de los Ice Breakers (actividades para romper el hielo) con el objetivo de que el alumno se integre en la dinámica de la asignatura, superando la desconfianza y el recelo iniciales que se presentan ante una materia nueva y/o un grupo nuevo de compañeros de clase. En ...

  16. Simulation of the Effects of Several Factors on Arc Plasma Behavior in Low Voltage Circuit Breaker

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Taking into account the properties of the arc plasma and the electromagnetic, heat and radiative phenomena, commercial computational fluid dynamics software PHOENICS has been adapted and modified to develop the three-dimensional magneto-hydrodynamic (MHD)model of arc in a low voltage circuit breaker. The effects of the arc ignition location, venting size and gassing material on arc behavior have been investigated. The analysis of the results show that the arc velocity accelerates with the increase in the distance between arc ignition location and of the venting size, and the existence of the gassing material is beneficial to improving the arc voltage and reducing the arc temperature.

  17. A novel advanced glycation endproducts breaker restores cardiovascular dysfunctions in experimental diabetic rats

    Institute of Scientific and Technical Information of China (English)

    GangCHENG; Li-liWANG; Hong-yingLIU; HaoCUI; Ying-linCAO; SongLI

    2005-01-01

    AIM The formation of advanced glycation endproducts (AGEs) on connective tissue and matrix components leads to increases in collagen crosslinkingthat contributes to aortic and myocardial stiffness in normal aging and which occurs at an accelerated rate in diabetes. In this study, we examined the effects of a novel AGEs breaker, C36, on cardiovascular dysfunctions in experimental diabetic rats. METHODS and RESULTS Male Wiatar rats were made diabetic by i.p. injection of 70mg/kg streptozotocin. After 12 weeks of diabetes, the animals were randomly divided into 4 groups (n=8-11),

  18. Power nanosecond pulse shaping by means of RCD-generators with peaking circuits based on diode current breakers

    CERN Document Server

    Grekhov, I V; Korotkov, S V; Stepanyants, A L; Khristyuk, D V

    2002-01-01

    One considered the basic principles to design nanosecond region generators based on reverse-connected dynistos (RCD) with diode current breaker base output peaking circuits. Paper presents the results of experimental investigation in intense generator based on RCD, peaking pulsed transformer and high-voltage diode breaker from a set of series-connected drift diodes with abrupt reset. Generator at 1 kHz frequency commutates voltage pulses with approx 45 kV amplitude, approx 50 ns duration and approx 10 ns rise front to 25 ohm load

  19. The Destiny of Universes After the Big Trip

    CERN Document Server

    Yurov, A V

    2007-01-01

    The big trip can be describe with the help of the Wheeler-DeWitt wave equation ${\\hat H}\\psi(w,a)=0$. The probability to find the universe after big trip in the state with $w=w_0$ will be maximal if $\\partial\\psi(w,a)/\\partial w|_{w=w_0}=0$ for any values of the scale factor $a$. It is shown that this will be the case if and only if $w_0=-1/3$. This fact allows one to suggest that vast majority of universes in multiverse must be in this state after their big trips.

  20. Advanced transportation concept for round-trip space travel

    Science.gov (United States)

    Yen, Chen-Wan L.

    1988-01-01

    A departure from the conventional concept of round-trip space travel is introduced. It is shown that a substantial reduction in the initial load required of the Shuttle or other launch vehicle can be achieved by staging the ascent orbit and leaving fuel for the return trip at each stage of the orbit. Examples of round trips from a low-inclination LEO to a high-inclination LEO and from an LEO to a GEO are used to show the merits of the new concept. Potential problem areas and research needed for the development of an efficient space transportation network are discussed.

  1. REVIEW AND PROSPECT OF HIGH STRENGTH LOW ALLOY TRIP STEEL

    Institute of Scientific and Technical Information of China (English)

    L. Li; P. Wollants; Y.L. He; B.C. De Cooman; X.C. Wei; Z.Y. Xu

    2003-01-01

    Research status of high strength low alloy TRIP (transformation induced plasticity)steels for automobile structural parts is briefly described. Composition and microstructure factors especially the morphology, size and volume fraction of retained austenite,which largely influence the strength and ductility of the steel, are reviewed and discussed one after another. Modelling of the inter-critical annealing and martempering processes as well as the designing of the TRIP steel aided by commercial software are introduced. Some special aspects of the dynamic mechanical properties of TRIP steel are firstly reported.

  2. Peer Pressure Road Trip 2012 - A Report

    Science.gov (United States)

    Popnoe, Olivia

    2012-10-01

    Each year since 2005 the Angelo State University SPS ``Peer Pressure Team'' has travelled for a week in May to promote physics and other sciences for grades K-12. This year, the Peer Pressure Team visited schools in West Texas and New Mexico. This was the first year the team has traveled outside of Texas, inspired by the SPS 2012 theme ``Physics Beyond Borders.'' The purpose of the Road Tours is to encourage an interest in science in children in grades K-12 and give experience in presenting and explaining physics to the undergraduate volunteers. The schools attended are carefully selected based on socioeconomic need and an underrepresentation in physics, as well as other sciences. During this week, the Peer Pressure Team saw about 1,500 students over 10 shows. Surveys were given to teachers post-demonstration to have students complete and return so the Team could gauge the effectiveness of the outreach program. In addition, the surveys allow the Team to determine which demonstrations had the most impact. We present the details of this year's road trip with the results and analysis of the survey data.

  3. Study on the Mathematical Model of Dielectric Recovery Characteristics in High Voltage SF6 Circuit Breaker

    Science.gov (United States)

    Lin, Xin; Wang, Feiming; Xu, Jianyuan; Xia, Yalong; Liu, Weidong

    2016-03-01

    According to the stream theory, this paper proposes a mathematical model of the dielectric recovery characteristic based on the two-temperature ionization equilibrium equation. Taking the dynamic variation of charged particle's ionization and attachment into account, this model can be used in collaboration with the Coulomb collision model, which gives the relationship of the heavy particle temperature and electron temperature to calculate the electron density and temperature under different pressure and electric field conditions, so as to deliver the breakdown electric field strength under different pressure conditions. Meanwhile an experiment loop of the circuit breaker has been built to measure the breakdown voltage. It is shown that calculated results are in conformity with experiment results on the whole while results based on the stream criterion are larger than experiment results. This indicates that the mathematical model proposed here is more accurate for calculating the dielectric recovery characteristic, it is derived from the stream model with some improvement and refinement and has great significance for increasing the simulation accuracy of circuit breaker's interruption characteristic. supported by Science and Technology Project of State Grid Corporation of China (No. GY17201200063), National Natural Science Foundation of China (No. 51277123), Basic Research Project of Liaoning Key Laboratory of Education Department (LZ2015055)

  4. Development of a test for water-in-oil emulsion breakers

    International Nuclear Information System (INIS)

    Studies have been conducted on the breaking of water-in-oil emulsions to develop a standard test for emulsion breaking agents, to test commercial products, and to understand the physics of emulsions. A review of the literature on the physics of emulsification is presented, showing the effects on emulsion formation of polar and asphaltene compounds in the oil. Nine basic test methods and several variations of each were developed, with successive tests developed to solve problems noted with earlier tests. The tests had to have a high degree of repeatability, aspects of the test methods had to be analogous to the sea and the practical application of emulsion breaking agents, and the test results had to relate to physical understanding of phenomena. Once a basic test was established, a series of studies was conducted to examine optimal time of shaking, the possibility of substituting settling time for shaking time, the relationship between energy of shaking and demuslfier effectiveness, and the effects of water to oil ratios. The studies show that a test for emulsion breakers can be developed to yield consistent results which are not entirely dependent on the shaking methods or vessels. The critical factor is the stability of the emulsion being tested, since unstable emulsions will show anomalous results. Other major factors are the type of emulsion breaker being tested and the determination of endpoint. 17 refs. 17 figs., 18 tabs

  5. You Can't Reach for the Stars if You are Tripping Over the Ground! (Preventing Slips, Trips, and Falls)

    Science.gov (United States)

    Miller, Darcy; Raysich, Mark; Kirkland, Mary

    2016-01-01

    Although there are very few mishaps related to ground, vehicle or payload processing at the Kennedy Space Center (KSC), employees have experienced a significant number of injuries due to slips, trips, and falls outside of performing flight processing operations. Slips, trips, and falls are major causes of occupational injuries at KSC, the National Aeronautics and Space Administration (NASA), and in general industry. To help KSC employees avoid these injuries, and allow them to be fully productive, KSC launched an initiative in 2013 to reduce slips, trips, and falls. This initiative is based on a four-part model focusing on DATA analysis, HAZARD awareness, PREVENTIVE methods, and BALANCE.

  6. 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...

  7. 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...

  8. [July 1999 trip report : Kirwin National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes a trip to Kirwin National Wildlife Refuge in 1999. It provides general background on the refuge, and reviews recreational activities, habitat...

  9. [August 1992 trip report : Kirwin NWR and Rainwater Basin WMD

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This trip report evaluates the current years farming and grazing results for Kirwin National Wildlife Refuge and Rainwater Basin Wetland Management District.

  10. Trip to Fish Springs - August 21, 22, 1959

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document discusses field survey results from several trips to Fish Springs National Wildlife Refuge in August 1959. The following topics are outlined; water...

  11. 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.

  12. My trip to Britain,my greatest inspiration

    Institute of Scientific and Technical Information of China (English)

    陈嘉瑜

    2015-01-01

    During a summer vacation I went to Britain to visit our sister school there with the teachers and students delegation in our school for a cross-cultural communication trip and we stayed there for about a month.What I saw and experienced during the trip broadened my horizon and had a great effect on me and it’s really a wonderful and unforgettable experience in my life.

  13. Systematic comparison of trip distribution laws and models

    OpenAIRE

    Lenormand, Maxime; Bassolas, Aleix; Ramasco, José J.

    2015-01-01

    Trip distribution laws are basic for the travel demand characterization needed in transport and urban planning. Several approaches have been considered in the last years. One of them is the so-called gravity law, in which the number of trips is assumed to be related to the population at origin and destination and to decrease with the distance. The mathematical expression of this law resembles Newton's law of gravity, which explains its name. Another popular approach is inspired by the theory ...

  14. Modelling leisure day trips between Berlin and its surrounding

    OpenAIRE

    Beuck, Ulrike

    2005-01-01

    The paper describes the development, application and validation of a quantitative spatial model for leisure day trips from Berlin into the surrounding regions. Leisure activities can contribute substantially to the economies of rural regions like the surroundings of Berlin, but these activities are also often very sensitive to environmental quality, which is usually negatively affected by the traffic caused by the leisure travelers...A model of the spatial distribution of leisure day trips ca...

  15. Systematic comparison of trip distribution laws and models

    OpenAIRE

    Lenormand, Maxime; Bassolas, Aleix; José J. Ramasco

    2016-01-01

    Trip distribution laws are basic for the travel demand characterization needed in transport and urban planning. Several approaches have been considered in the last years. One of them is the so-called gravity law, in which the number of trips is assumed to be related to the population at origin and destination and to decrease with the distance. The mathematical expression of this law resembles Newton's law of gravity, which explains its name. Another popular approach is inspired by the theory ...

  16. A Field Trip without Buses: Connecting Your Students to Scientists through a Virtual Visit

    Science.gov (United States)

    Adedokun, Omolola; Parker, Loran Carleton; Loizzo, Jamie; Burgess, Wilella; Robinson, J. Paul

    2011-01-01

    One school offers zipTrips as an alternative to actual field trips taken outside of school. ZipTrips are web- and broadcast-delivered electronic field trips that include online videos, lesson plans, and a live, 45-minute interactive program consisting of four core components: an in-studio audience, live interaction with scientists, prerecorded…

  17. 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…

  18. Round trip landing missions to the asteroid Eros, 1981 opportunity

    Science.gov (United States)

    Zambo, G. A.

    1971-01-01

    A comprehensive, Del V (magnitude of impulsive velocity-change vector) study of short staytime (0 to 30 days), short total trip time (10 to 160 days) round trip landing missions (fast missions) is presented. The characteristics of the following selected round trip landing missions are described: mission A (fast mission) with 120-day total trip time, 0-day stay-time, and 73,000-fps total mission Del V; mission B (opposition class) with 380-day total trip time, 0-day staytime, and 52,000-fps total mission Del V; and mission C (conjuction class) with 540-day total trip time, 175-day staytime, and 39,000-fps total mission Del V. A study of large-tank Agena, chemical propulsion stage (CPS), and nuclear stage was conducted. A payload of 5000 pounds was assumed. The propulsion requirements for mission A were found to be two large-tank Agenas and ten CPSs (or alternatively, two large-tank Agenas and five nuclear stages) while mission B required two large-tank Agenas and two CPSs. Mission C can be performed with one large-tank Agena and one CPS.

  19. Development and formability analysis of TRIP seamless steel tube

    Institute of Scientific and Technical Information of China (English)

    Zhang Zicheng; Zhu Fuxian

    2014-01-01

    In this paper,the production technology of transformation induced plasticity (TRIP) steel was first introduced into the steel tube manufacture field to produce the steel tubes with high strength and plasticity. The TRIP seamless steel tubes with the microstructure of ferrite,bainite,retained austenite and a little martensite were successfully fabricated using a cold-drawn steel tube with two-stage heat treatment technique and continu-ous heat treatment process,respectively. The ring tensile test and cold bend test were carried out to study the formability of the newly developed TRIP seamless steel tube. The results showed that the TRIP seamless steel tubes have a good cold formability,and they are available to be used in the tube hydroforming process. In ad-dition,the equipment of continuous heat treatment developed in the current study can be used to produce TRIP steel tube,and it may serve as an important reference for the industrial production of TRIP steel tube.

  20. Tripping Effects on the Friction Factor in Turbulent Pipe Flows

    Science.gov (United States)

    Al-Salaymeh, A.; Bayoumi, O. A.; Durst, F.; Gad-El-Hak, M.

    2004-11-01

    Tripping devices are usually installed at the entrance of laboratory-scale pipe test sections to obtain a fully developed turbulent flow sooner. The tripping of laminar flow to induce turbulence can be carried out in different ways, such as using cylindrical wires, sand papers, well-organized tape letters, fences, etc. Claims of tripping effects have been made periodically since the classical experiments of Nikuradse (1932), which covered a significant range of Reynolds numbers. NikuradseÂ's data have become the metric by which theories are established, and have also been the subject of intense scrutiny. Several subsequent experiments reported friction factors as much as 5% lower than those measured by Nikuradse, and the authors of those reports attributed the difference to tripping effects. In the present study, measurements with and without ring tripping devices of different blocking areas of 10%, 20%, 30% and 40% have been carried out to determine the effect of entrance condition on the developing flow field in pipes. Along with pressure drop measurements to compute the skin friction, both Pitot tube and hot-wire anemometry measurements have been used to accurately determine the mean velocity profile over the working test section at different Reynolds numbers in the range of 1× 10^5--4.5 × 10^5. The results we obtained suggest that the tripping technique has an insignificant effect on the wall friction factor, in agreement with Nikuradse's original data.

  1. User Oriented Trajectory Search for Trip Recommendation

    KAUST Repository

    Ding, Ruogu

    2012-07-08

    Trajectory sharing and searching have received significant attention in recent years. In this thesis, we propose and investigate the methods to find and recommend the best trajectory to the traveler, and mainly focus on a novel technique named User Oriented Trajectory Search (UOTS) query processing. 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’s preference, it will be recommended to the traveler. This type of queries can enable many popular applications such as trip planning and recommendation. There are two challenges in UOTS query processing, (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. Extensive experiments are conducted on both real and synthetic trajectory data in road networks. Our approach is verified to be effective in reducing both CPU time and disk I/O time.

  2. User Oriented Trajectory Search for Trip Recommendation

    KAUST Repository

    Ding, Ruogu

    2012-09-08

    Trajectory sharing and searching have received significant attention in recent years. In this thesis, we propose and investigate the methods to find and recommend the best trajectory to the traveler, and mainly focus on a novel technique named User Oriented Trajectory Search (UOTS) query processing. 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’s preference, it will be recommended to the traveler. This type of queries can enable many popular applications such as trip planning and recommendation. There are two challenges in UOTS query processing, (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 or- dered. Extensive experiments are conducted on both real and synthetic trajectory data in road networks. Our approach is verified to be effective in reducing both CPU time and disk I/O time.

  3. Incremento del porcentaje de breakers que pasan la calibración magnética en la linea FA Maggard para Schneider Electric

    OpenAIRE

    Gamboa Corzas, Ramón

    2005-01-01

    El objetivo principal de este trabajo consistió en incrementar el porcentaje de breakers que pasan la prueba de calibración magnética en la linea de ensamble de breakers FA Maggard en la empresa Schneider Electric. El problema principal es que el porcentaje de breakers que pasan la calibración magnética en esta línea ha sido tan solo del 80% en los meses de mayo, junio y julio del 2005, ocasionando por consecuencia una eficiencia del 60%, un retrabajo de 76 hrs. mensuales y ...

  4. Fatigue Properties of TRIP800 Steel Plate%TRIP800钢板疲劳性能研究

    Institute of Scientific and Technical Information of China (English)

    于燕; 杨海峰

    2012-01-01

    对厚度为1.8mm的国产TRIP800 MPa钢板进行疲劳试验,并运用最小二乘法对试验数据进行拟合,获得了在对称循环应力下的疲劳经验公式.结果表明:TRIP800 MPa钢板在加载频率为8Hz、R=0的条件下疲劳极限是560MPa;TRIP800钢板的疲劳裂纹源位于表面下的夹杂物处,裂纹扩展区为韧性断裂,瞬断区为脆性断裂.%A fatigue life test was carried out on 1.8 mm domestic TRIP800 MPa steel plate. The least square method was used to fit, and then the symmetrical cyclic stress of fatigue experience formula was obtained. The results show that TRIP800 MPa steel plate loading for 8 Hz in frequency, R=0 condition: fatigue limit is 560 MPa. TRIP800 steel plate fatigue crack source is located under the surface of the inclusion place, crack growth area for the ductile fracture, transient breaking area for the brittle fiacture.

  5. Record breakers

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    In the sixties, CERN’s Fellows were but a handful of about 50 young experimentalists present on site to complete their training. Today, their number has increased to a record-breaking 500. They come from many different fields and are spread across CERN’s different activity areas.   “Diversifying the Fellowship programme has been the key theme in recent years,” comments James Purvis, Head of the Recruitment, Programmes and Monitoring group in the HR Department. “In particular, the 2005 five-yearly review introduced the notion of ‘senior’ and ‘junior’ Fellowships, broadening the target audience to include those with Bachelor-level qualifications.” Diversification made CERN’s Fellowship programme attractive to a wider audience but the number of Fellows on site could not have increased so much without the support of EU-funded projects, which were instrumental in the growth of the programme. ...

  6. Study on Restrike Phenomena for 40.5-kV Vacuum Circuit Breakers

    Institute of Scientific and Technical Information of China (English)

    Yan Jing; Ma Zhiying

    2006-01-01

    When interrupting short circuit fault by 40.5-Kv vacuum circuit breakers, it is significant to eliminate multiple restrike phenomena, which occur frequently and result in high overvoltage and even interruption failure. A synthetic circuit that can supply a DC recovery voltage after current zero was used to study multiple restrike phenomena in switching. Some key factors including breaking current, clearance between open contacts, electrode structure and contact material, which may affect restrike characteristics, were studied. Under various clearances, the statistical probability of restrike was obtained. As a result, the best scope of clearance between open contacts was found. The performance of CuCrS0/50 and CuCr75/25 material were compared. Two kinds of electrode structures, namely 1/2 coil structure and cup-shaped axial magnetic structure, were tested. After a high-current interruption, conditioning effect was realized and the probability ofrestrike decreased.

  7. Plasma circuit breaker in a magnetic field as a high-power ion flux generator

    International Nuclear Information System (INIS)

    It is ascertained that plasma circuit breaker (PCB) in the external magnetic field of acute-anguled geometry in the mode when PCB serves as inductive storage loading is a natural magnetoizolated diode. Using PCB as an ion emitter and as a high-voltage generator it proved possible in case of full electron magnetiuzation to attain the maximum efficiency of the storage. The density of ion current evaluated by the measured energy density for 30 J/cm2 thermocouple and by the energy of 1.5 MeV constitutes 100 A/cm2. The given method of ion generation is very effective when high ion currents with a high energy are required

  8. 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.

  9. The Influence of Contact Space on Arc Commutation Process in Air Circuit Breaker

    Institute of Scientific and Technical Information of China (English)

    NIU Chunping; DING Juwen; YANG Fei; DONG Delong; RONG Mingzhe; XU Dan

    2016-01-01

    In this paper,a 3D magneto-hydrodynamic (MHD) arc simulation model is applied to analyze the arc motion during current interruption in a certain air circuit breaker (ACB).The distributions of pressure,temperature,gas flow and current density of the arc plasma in the arc region are calculated,and the factors influencing the commutation process are analyzed according to the calculated results.Based on the airflow in the arc chamber,the causes of arc commutation asynchrony and the back commutation are investigated.It indicates that a reasonable contact space design is crucial to a successful arc commutation process.To verify the simulation results,the influence of contact space on arc voltage and arc commutation is tested.This research can provide methods and references to the optimization of ACB design.

  10. Reduction of Switching Surge by Controlled Shunt Reactor Switching of Gas Circuit Breaker

    Science.gov (United States)

    Kohyama, Haruhiko; Ito, Hiroki; Asai, Jun; Hidaka, Mikio; Yonezawa, Takashi

    Controlled switching system (CSS) with a 204kV gas circuit breaker (GCB) demonstrates to reduce an inrush current and to eliminate re-ignitions in shunt reactor switching. Target closing and opening instants for controlled switching are determined by the electrical and mechanical characteristics of GCB. Idle time dependence of the operating time, which gives a sufficient impact on controlling accuracy, is evaluated and successfully compensated by synchronous switching controller (SSC). Field operation of CSS for a year shows an effective suppression of inrush current on closing and prevention of re-ignitions on opening of shunt reactor. The operations also proved that the CSS has a satisfactory performance for electro-magnetic disturbance imposed in practical field.

  11. New Breakdown Electric Field Calculation for SF6 High Voltage Circuit Breaker Applications

    Institute of Scientific and Technical Information of China (English)

    Ph.ROBIN-JOUAN; M.YOUSFI

    2007-01-01

    The critical electric fields of hot SF6 are calculated including both electron and ion kinetics in wide ranges of temperature and pressure,namely from 300 K up to 4000 K and 2 atmospheres up to 32 atmospheres respectively.Based on solving a multi-term electron Boltzmann equation the calculations use improved electron-gas collision cross sections for twelve SF6 dissociation products with a particular emphasis on the electron-vibrating molecule interactions.The ion kinetics is also considered and its role on the critical field becomes non negligible as the temperature is above 2000 K.These critical fields are then used in hydrodynamics simulations which correctly predict the circuit breaker behaviours observed in the case of breaking tests.

  12. Study of switching electric circuits with DC hybrid breaker, one stage

    Science.gov (United States)

    Niculescu, T.; Marcu, M.; Popescu, F. G.

    2016-06-01

    The paper presents a method of extinguishing the electric arc that occurs between the contacts of direct current breakers. The method consists of using an LC type extinguishing group to be optimally sized. From this point of view is presented a theoretical approach to the phenomena that occurs immediately after disconnecting the load and the specific diagrams are drawn. Using these, the elements extinguishing group we can choose. At the second part of the paper there is presented an analyses of the circuit switching process by decomposing the process in particular time sequences. For every time interval there was conceived a numerical simulation model in MATLAB-SIMULINK medium which integrates the characteristic differential equation and plots the capacitor voltage variation diagram and the circuit dumping current diagram.

  13. Inhibition of aggregation of amyloid peptides by beta-sheet breaker peptides and their binding affinity.

    Science.gov (United States)

    Viet, Man Hoang; Ngo, Son Tung; Lam, Nguyen Sy; Li, Mai Suan

    2011-06-01

    The effects of beta-sheet breaker peptides KLVFF and LPFFD on the oligomerization of amyloid peptides were studied by all-atom simulations. It was found that LPFFD interferes the aggregation of Aβ(16-22) peptides to a greater extent than does KLVFF. Using the molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) method, we found that the former binds more strongly to Aβ(16-22). Therefore, by simulations, we have clarified the relationship between aggregation rates and binding affinity: the stronger the ligand binding, the slower the oligomerization process. The binding affinity of pentapeptides to full-length peptide Aβ(1-40) and its mature fibrils has been considered using the Autodock and MM-PBSA methods. The hydrophobic interaction between ligands and receptors plays a more important role for association than does hydrogen bonding. The influence of beta-sheet breaker peptides on the secondary structures of monomer Aβ(1-40) was studied in detail, and it turns out that, in their presence, the total beta-sheet content can be enhanced. However, the aggregation can be slowed because the beta-content is reduced in fibril-prone regions. Both pentapeptides strongly bind to monomer Aβ(1-40), as well as to mature fibrils, but KLVFF displays a lower binding affinity than LPFFD. Our findings are in accord with earlier experiments that both of these peptides can serve as prominent inhibitors. In addition, we predict that LPFFD inhibits/degrades the fibrillogenesis of full-length amyloid peptides better than KLVFF. This is probably related to a difference in their total hydrophobicities in that the higher the hydrophobicity, the lower the inhibitory capacity. The GROMOS96 43a1 force field with explicit water and the force field proposed by Morris et al. (Morris et al. J. Comput. Chem. 1998, 19, 1639 ) were employed for all-atom molecular dynamics simulations and Autodock experiments, respectively. PMID:21563780

  14. 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.

  15. 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

  16. 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...

  17. 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. PMID:24505847

  18. 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.

  19. Microstructure and Mechanical Properties of High Manganese TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jin-long; XI Yan; SHI Wen; LI Lin

    2012-01-01

    Microstructure evolution and mechanical properties of newly designed 0.1C-6Mn-0.5Si-1Al TRIP-aided steels under different annealing conditions and the effects of matrix microstructure before intercritical annealing on the final microstructure were studied by means of X-ray diffraction(XRD),scanning electron microcopy(SEM),dilatometric simulation,optical microstructure(OM) and tensile testing in this work.The experimental results indicate that the TRIP steel with Mn of 6% could form a considerable amount of retained austenite with good TRIP effect after a simple intercritical annealing treatment,and the matrix microstructure before intercritical annealing treatment can greatly affect the final microstructure.The original microstructure of the ferritic matrix steel was eliminated,while annealed martensite was remained from the martensite matrix steel under the same intercritical annealing conditions

  20. Mechanical and Microstructural Characterization of an Aluminum Bearing Trip Steel

    Science.gov (United States)

    Monsalve, Alberto; Guzmán, Alexis; De Barbieri, Flavio; Artigas, Alfredo; Carvajal, Linton; Bustos, Oscar; Garza-Montes-de Oca, Nelson F.; Colás, Rafael

    2016-06-01

    The mechanical properties and microstructural characteristics of a steel able to sustain the TRIP-effect were studied. The material was prepared by taking in mind the partial substitution of silicon by aluminum following a processing route that included hot forging, hot and cold rolling, intercritical annealing, and a final bainitic isothermal treatment. The mechanical properties that were obtained resulted to be above those of commercial a 780 TRIP steel. The TRIP phenomenon was confirmed by the change in retained austenite before and after deforming the steel; X-ray diffraction was used to evaluate the volume content of retained austenite. Formability of the steel under study can be rationalized in terms of the texture developed in the material.

  1. Field trips in the southern Rocky Mountains, USA

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, E.P.; Erslev, E.A. (eds.)

    2004-07-01

    The theme of the 2004 GSA Annual Meeting and Exposition, 'Geoscience in a Changing World' covers both new and traditional areas of the earth sciences. The Front Range of the Rocky Mountains and the High Plains preserve an outstanding record of geological processes from Precambrian through Quaternary times, and thus served as excellent educational exhibits for the meeting. The chapters in this field guide all contain technical content as well as a field trip log describing field trip routes and stops. Of the 25 field trips offered at the Meeting. 14 are described in the guidebook, covering a wide variety of geoscience disciplines, with chapters on tectonics (Precambrian and Laramide), stratigraphy and paleoenvironments (e.g., early Paleozoic environments, Jurassic eolian environments, the K-T boundary, the famous Oligocene Florissant fossil beds), economic deposits (coal and molybdenum), geological hazards, and geoarchaeology. Two papers have been abstracted separately for the Coal Abstracts database.

  2. 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.

  3. 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...... Welding (FSSW) is investigated. The aim of the study is to investigate whether acceptable welds can be produced, and additionally, to obtain an understanding of the microstructural changes during welding. The microstructure was investigated with a combination of microscopical techniques with the aim...... of identifying the transformations occurring during welding. Reflected light microscopy, scanning electron microscopy, and electron backscatter diffraction were among the methods applied for detailed investigations. The microstructure adjacent to the welds can generally be subdivided in two thermo...

  4. 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.

  5. Understanding Trajectories of Experience in Situated Learning Field Trips

    Directory of Open Access Journals (Sweden)

    Ilaria Canova Calori

    2013-05-01

    Full Text Available This paper discusses the role context plays in promoting engagement and exploration in situated learning experiences during field trips. We look at field trips where children engage with the physical and social context in order to learn about cultural and social aspects of the city they live in. By drawing on empirical data collected by means of qualitative methods, we discuss how learning unfolds along trajectories of experience towards pre-defined and emerging learning objectives. We reflect of the role technology can play in sup-porting learning experiences outside the classroom.

  6. What drives people? Analyzing leisure-shopping trip decisions making

    OpenAIRE

    DE CEUNYNCK, Tim; KUSUMASTUTI, Diana; HANNES, Els; JANSSENS, Davy; Wets, Geert

    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. Thus, this paper highlights individuals’ leisure-trip decision-making processes. The uniqueness of this study is the use of a large sample group, consisting of 221 respondents. A Computer-Based Causa...

  7. Bake hardening behavior of TRIP and DP steels

    Institute of Scientific and Technical Information of China (English)

    Jicheng Zhang; Renyu Fu; Mei Zhang; Rendong Liu; Xicheng Wei; Lin Li

    2008-01-01

    The bake hardening (BH) behavior of transformation-induced plasticity (TRIP) and dual-phase (DP) steels after different prestrains was studied. The experimental results indicate that TRIP steel exhibits good BH ability while DP steel does not, and prestrain displays a strong effect on the BH values of both steels. The comparison of microstructures of the two steels showed that the hard second phase in the matrix might be harmful to the BH ability. For deformed specimens, baking resulted in a loss of uniform elongation, but there was no obvious decrease in uniform elongation for unprestrained specimens.

  8. 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.)

  9. Ultrahigh spatiotemporal resolved spectroscopy

    Institute of Scientific and Technical Information of China (English)

    LI; Zhi

    2007-01-01

    We review the technique and research of the ultrahigh spatiotemporal resolved spectroscopy and its applications in the field of the ultrafast dynamics of mesoscopic systems and nanomaterials. Combining femtosecond time-resolved spectroscopy and scanning near-field optical microscopy (SNOM), we can obtain the spectra with ultrahigh temporal and spatial resolutions simultaneously. Some problems in doing so are discussed. Then we show the important applications of the ultrahigh spatiotemporal resolved spectroscopy with a few typical examples.……

  10. 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.

  11. Computer simulation of equilibrium conditions following a plant 'trip'

    Science.gov (United States)

    Limb, D.

    When a process or part of a process experiences an emergency 'trip', the contained fluids redistribute themselves based upon the prevailing pressure gradients and depending upon the positions of valves at the time of the trip. Reverse flow through rotating compression machinery may occur, depending upon the locations of non-return valves. Reduction in pressure and mixing of cryogenic fluids of different compositions and/or temperatures can both lead to generation of significant volumes of vapour. This equilibration process is usually largely over in a matter of seconds rather than minutes. Key questions facing process and mechanical designers are: what is the settle-out pressure, and can we ensure relief valves do not lift following a trip? To answer these related questions it is necessary to analyse the state of the system prior to the trip, and then, based upon valve positions, etc., construct a model of the worst case probable scenarios for the qualitative redistribution of fluid inventory. At this point the simulation program may be employed to help calculate rigorously the final settle out conditions for each of the possible scenarios. This technique is particularly appropriate for cryogenic processes including refrigeration cycles. It is illustrated here with the help of a multistage hydrocarbon compressor example. Other related non-standard applications of the steady state process simulation program are identified.

  12. Solving touristic trip planning problem by using taboo search approach

    Directory of Open Access Journals (Sweden)

    Kadri Sylejmani

    2011-09-01

    Full Text Available In this paper, we introduce an algorithm that automatically plans a touristic trip by considering some hard and soft constrains. Opening and closing hours of POIs, trip duration and trip allocated budget represent the hard constraints, while the satisfaction factors of the POIs and travelling distance in the trip are considered as soft constraints. We use the soft constraints to evaluate the generated solution of the algorithm. The algorithm is developed by utilizing the taboo search method as a meta heuristic. The operators of Swap, Insert and Delete are used to explore the search space. The Swap and Insert operator are used in each iteration of the algorithm loop, while the Delete operator is used whenever the algorithm tends to enter in an endless cycle. The algorithm is developed by using Java programming language, while the data repositories are created in the XML format. The algorithm is tested with 40 instances of POIs of the city of Vienna. Various entry parameters of the algorithm are used to test its performance. The results gained are discussed and compared in respect to the optimal solution.

  13. Geïntegreerde trips- en spintbestrijding in chrysant

    NARCIS (Netherlands)

    Beerling, E.A.M.; Berg, van den D.

    2008-01-01

    Raspportage van vierjarig project (2001-2004) waarbij op semi-praktijkschaal in proefkassen werd onderzocht wat de werkelijke bijdrage van natuurlijke vijanden en biologische middelen aan de bestrijding van trips en spint in chrysant is. Op basis hiervan werd geprobeerd zinvolle geïntegreerde bestri

  14. 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...

  15. TRIPS Agreement, International Technology Transfer and Least Developed Countries

    Directory of Open Access Journals (Sweden)

    Mark V. Shugurov

    2015-04-01

    Full Text Available The author examines the role of the trade-related aspects of intellectual property rights (TRIPS Agreement in facilitation the international technology transfer to least developed countries (LDCs. The primary purpose of this study is to investigate the new conditions of technology development of LDCs connected with TRIPS adoption. Special attention is paid to the potentials of Article 66.2 for solving the problem of LDCs capacity building. The article presents detailed analysis of the discussions on the impact of the TRIPS provisions concerning the strengthening of the intellectual property rights (IPRs and the protection of technology transfer to LDCs. An important finding of this study is the recognition of the need to take urgent measures for the transition unto a new model of partnership between developed countries and LDCs in area of technology transfer and IPRs protection. The study concluded that a new model needed to be elaborated at the international level should be based on the effective implementation of Article 66.2 of the TRIPS Agreement.

  16. 49 CFR 236.586 - Daily or after trip test.

    Science.gov (United States)

    2010-10-01

    ..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.586 Daily or after trip test..., each locomotive equipped with an automatic cab signal or train stop or train control device...

  17. A model for sustainable short-term international medical trips.

    Science.gov (United States)

    Suchdev, Parminder; Ahrens, Kym; Click, Eleanor; Macklin, Lori; Evangelista, Doris; Graham, Elinor

    2007-01-01

    The health status of many people in developing countries is often dismal compared with the norms in industrialized countries. Increasingly, medical practitioners in the United States and other industrialized countries have become interested in global health issues, an interest that often takes the form of short-term international medical trips. We discuss several ethical issues associated with participation in such trips and use our experiences in developing the Children's Health International Medical Project of Seattle (CHIMPS) to outline and illustrate a set of 7 guiding principles for making these trips. CHIMPS is a resident-run, faculty-supported international medical program founded in 2002 by pediatric residents at the University of Washington in Seattle. Members of CHIMPS work with a rural community in El Salvador to support ongoing public health interventions there and provide sustainable medical care in collaboration with the community and a local nongovernmental organization. The 7 principles developed as a result of this work-mission, collaboration, education, service, teamwork, sustainability, and evaluation-can be used as a model for health practitioners as they develop or select international medical trips. The importance of partnering with the community and working within the existing medical and public health infrastructure is emphasized. Many of the challenges of doing international medical work can be overcome when efforts are guided by a few specific principles, such as those we have outlined. PMID:17660105

  18. Systematic comparison of trip distribution laws and models

    CERN Document Server

    Lenormand, Maxime; Ramasco, José J

    2016-01-01

    Trip distribution laws are basic for the travel demand characterization needed in transport and urban planning. Several approaches have been considered in the last years. One of them is the so-called gravity law, in which the number of trips is assumed to be related to the population at origin and destination and to decrease with the distance. The mathematical expression of this law resembles Newton's law of gravity, which explains its name. Another popular approach is inspired by the theory of intervening opportunities and it has been concreted into the so-called radiation models. Individuals are supposed to travel until they find a job opportunity, so the population and jobs spatial distributions naturally lead to a trip flow network. In this paper, we perform a thorough comparison between the gravity and the radiation approaches in their ability at estimating commuting flows. We test the gravity and the radiation laws against empirical trip data at different scales and coming from different countries. Diff...

  19. 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)

  20. Un Viaje al Aeropuerto (A Trip to the Airport).

    Science.gov (United States)

    Federal Aviation Administration (DOT), Washington, DC.

    This illustrated, bilingual Spanish-English intermediate reader describes a class trip to an airport, in which the class tours the airport, and learns about airport activities, the parts of an airplane, and other related topics. Each page of the text is illustrated with a drawing. The narrative is followed by a list of 24 suggested learning…

  1. What drives people? Analyzing leisure-shopping trip decision making

    NARCIS (Netherlands)

    De Ceunynck, T.; Kusumastuti, D.; 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. Th

  2. 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,...

  3. 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.

  4. A Heuristic for Locating Electric Vehicle Charging Stations for Trip Chains

    DEFF Research Database (Denmark)

    Wen, Min; Røpke, Stefan

    We present the problem of locating a limited number of electric vehiclecharging stations for a given set of trip chains, each of which consistsof a series of linked short trips and is represented by a sequence ofintervening stops along the trip chain. The objective of this problemis to maximize...... the number of trip chains that can be completed by the electric vehicle without running out of battery. A mixed-integer programmingformulation as well as a heuristic for solving this problemwill be presented....

  5. The Practice of Prospective Science Teachers regarding the Planning of Education Based Trips: Evaluation of Six Different Field Trips

    Science.gov (United States)

    Bozdogan, Aykut Emre

    2012-01-01

    The aim of this study is to explain how planning educational trips out of school environments for training purposes should be as well as to determine the opinions and the practices of prospective science teachers. The study that lasted for two years was carried out in parallel with the elective course "Science Education in Informal Learning…

  6. 基于MATLAB仿真的缓冲器对断路器分闸特性影响研究%Simulation Study on the Influence of Multi-orifice Hydraulic Buffer on Opening Characteristics of High Voltage Circuit Breaker Based on MATLAB

    Institute of Scientific and Technical Information of China (English)

    余明星; 赵伟涛

    2015-01-01

    为研究用于弹簧操动机构中的排孔式液压缓冲器结构参数对高压断路器分闸特性的影响,文中以排孔式缓冲器工作原理为基础建立了缓冲过程的数学模型,应用MATLAB对数学模型进行仿真求解。仿真所得曲线与试验曲线相吻合,证明了仿真的准确性,并依此为依据,仿真得到缓冲器在不同阻尼孔直径、不同阻尼孔位置、不同活塞与缸体配合间隙以及不同分闸弹簧刚度下对断路器分闸特性的影响,该研究为设计出满足断路器分合特性的缓冲器提供了理论指导。%In order to investigate the influence of structure parameters of multi-orifice hydraulic buffer which used in the spring operating mechanism of high voltage circuit breaker to the opening operation , in this paper, a mathematical model of cushioning process based on buffer working principle is established. Then simulate and solve such mathematical model by MATLAB. First of all , to verify the simulation accuracy, the simulation and experimental curves are compared and analyzed. Then on this basis, through numerical simulation, it is found that the diameter and the spacing interval of damped orifice, the clearance between piston and cylinder block, and the stiffness of trip spring would influence the opening operation of circuit breaker. This study provides the theoretical guidance for designing and optimizing the performance of hydraulic buffer.

  7. 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.

  8. The Effectiveness of a Virtual Field Trip (VFT) Module in Learning Biology

    Science.gov (United States)

    Haris, Norbaizura; Osman, Kamisah

    2015-01-01

    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…

  9. 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 t

  10. 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

  11. Improving Transient Recovery voltage of circuit breaker using Fault Current Limiter

    Directory of Open Access Journals (Sweden)

    Amir Heidary

    2012-12-01

    Full Text Available This study investigates influence of Fault Current Limiter (FCL on short-circuits current level of substation bus bar splitter circuit breaker and its TRV. An approach for TRV evaluation is developed and applied for proposed power system as shown in this study. FCL circuit is connected to the power system in order to limit TRV. The limiter circuit consists of two equal windings which are turned around unique magnetic core. One of the windings is connected in series with the power system network and the other is connected to the network via series capacitor and power electronic switches. During normal operating condition, both tyristors are in on state and current of the primary and secondary windings are equal. This causes zero impedance of the limiter. During fault, faults current cause the power electronic switch to turn off which increases the limiter impedance. By increasing the limiter impedance, amplitude of TRV decreases substantially. The novel method presented in this study is a cheap and successful scheme.

  12. Simulation and Experimental Study of Arc Column Expansion After Ignition in Low-Voltage Circuit Breakers

    Institute of Scientific and Technical Information of China (English)

    MA Qiang; RONG Mingzhe; WU Yi; XU Tiejun; SUN Zhiqiang

    2008-01-01

    The dynamicprocess of arc pressure and corresponding arc column expansion, which is the main feature after arc ignition and has a significant effect on the breaking behaviour of low -voltage circuit breakers, is studied. By constructing a three dimensional mathematical model of air arc plasma and adopting the Control Volume Method, the parameters of arc plasma including temperature and pressure axe obtained. The variations of pressure field and temperature field with time are simulated. The result indicates that there are six stages for the process of arc column expansion according to the variation of pressure in arc chamber. In the first stage, the maximal pressure locates in the region close to cathode, and in the second stage the maximal pressure shifts to the region close to the anode. In the third stage, the pressure difference between the middle of arc column and the ambient gas is very large, so the arc column begins to expand apparently. In the fourth stage, the pressure wave propagates towards both ends and the maximal pressure appears at the two ends when the pressure wave reaches both sidewalls. In the fifth stage, the pressure wave is reflected and collides in the middle of the arc chamber. In the last stage, the propagation and reflection of pressure wave will repeat several times until a steady burning state is reached. In addition, the experimental results of arc column expansion, corresponding to the arc pressure variation, are presented to verify the simulation results.

  13. Vacuum interrupter, high reliability component of distribution switches, circuit breakers and contactors

    Institute of Scientific and Technical Information of China (English)

    SLADE Paul G.; LI Wang-pei; MAYO Stephen; SMITH R.Kirkland; TAYLOR Erik D.

    2007-01-01

    The use of vacuum interrupters (VIs) as the current interruption component for switches, circuit breakers, reclosers and contactors operating at distribution voltages has escalated since their introduction in the mid-1950's. This electrical product has developed a dominating position for switching and protecting distribution circuits. VIs are even being introduced into switching products operating at transmission voltages. Among the reasons for the VI's popularity are its compactness, its range of application, its low cost, its superb electrical and mechanical life and its ease of application. Its major advantage is its well-established reliability. In this paper we show how this reliability has been achieved by design, by mechanical life testing and by electrical performance testing. We introduce the "sealed for life" concept for the VI's integrity. We discuss this in terms of what is meant by a practical leak rate for VIs with a life of over 30 years. We show that a simple high voltage withstand test is an easy and effective method for monitoring the long-term vacuum integrity. Finally we evaluate the need for routine inspection of this electrical product when it is used in adverse ambient environments.

  14. Influence of Copper Vapor on Low-Voltage Circuit Breaker Arcs During Stationary and Moving States

    Institute of Scientific and Technical Information of China (English)

    MA Qiang; RONG Mingzhe; WU Yi; XU Tiejun; SUN Zhiqiang

    2008-01-01

    The influence of copper vapor on the low-voltage circuit breaker arcs is studied. A three-dimensional (3-D) magnetohydrodynamics(MHD) model of arc motion under the effect of external magnetic field is built up. By adopting the commercial computational fluid dynamics (CFD) package FLUENT based on control-volume method, the above MHD model is solved. For the mediums of air-1% Cu and air-10% Cu, the distributions of stationary temperature, pressure, electrical potential and the arc motion processes are compared with those of a pure air arc. The copper vapor diffusion process in the arc chamber and the distribution of copper vapor mass concentration are also simulated. The results shows that the copper vapor has a cooling effect on the arc plasma and can decrease the stationary voltage as well. Moreover, the presence of copper vapor can decelerate the arc motion in the quenching chambers. The maximal copper vapor concentration locates behind the arc root because of the existence of a "double vortex" near the electrodes.

  15. Numerical Study on Arc Plasma Behavior During Arc Commutation Process in Direct Current Circuit Breaker

    Institute of Scientific and Technical Information of China (English)

    杨飞; 马瑞光; 吴翊; 孙昊; 纽春萍; 荣命哲

    2012-01-01

    This paper focuses on the numerical investigation of arc plasma behavior during arc commutation process in a medium-voltage direct current circuit breaker (DCCB) contact system. A three-dimensional magneto-hydrodynamic (MHD) model of air arc plasma in the contact system of a DCCB is developed, based on commercial software FLUENT. Coupled electromagnetic and gas dynamic interactions are considered as usual, and a thin layer of nonlinear electrical resistance elements is used to represent the voltage drop of plasma sheath and the formation of new arc root. The distributions of pressure, temperature, gas flow and current density of arc plasma in arc region are calculated. The simulation results indicate that the pressure distribution related to the contact system has a strong effect on the arc commutation process, arising from the change of electrical conductivity in the arc root region. In DCCB contact system, the pressure of arc root region will be concentrated and higher if the space above the moving contact is enclosed, which is not good for arc root commutation. However, when the region is opened, the pressure distribution would be lower and more evenly, which is favorable for the arc root commutation.

  16. Calculation of Nozzle Ablation During Arcing Period in an SF6 Auto-Expansion Circuit Breaker

    Science.gov (United States)

    Zhang, Junmin; Lu, Chunrong; Guan, Yonggang; Liu, Weidong

    2016-05-01

    The nozzle ablation process is described as two phases of heat and ablation in the interruption for an SF6 circuit breaker in this paper. Their mathematical models are established with the Fourier heat conduction differential equation respectively. The masses of nozzle ablation with different arc durations and arc currents are calculated through the model of the nozzle ablation combined with an MHD (magneto-hydrodynamic) arc model. The time of the temperature rise on the inner surface of the nozzle under a given energy flux and of reaching the pyrolysis temperature under different energy fluxes is respectively analyzed. The relations between the mass of nozzle ablation and breaking current and arc duration are obtained. The result shows that the absorbing energy process before the nozzle ablation can be neglected under the condition of the energy flux entering into nozzle q > 109 W/m2. The ablation is the severest during the high-current phase and the ablation mass increases rapidly with the breaking current and with arc duration respectively. supported by National Natural Science Foundation of China (Nos. 51177005 and 51477004)

  17. Influence of a Circuit Breaker's Grading Capacitor on Controlled Transformer Switching

    Science.gov (United States)

    Corrodi, Yves; Kamei, Kenji; Kohyama, Haruhiko; Ito, Hiroki

    Controlled switching, taking into account the residual flux level within a transformer core, can effectively eliminate inrush currents. Many switching sequences assume the residual flux as a constant value, which can be obtained by a measurement after a transformer de-energization. However, in case of a transformer system that is switched by a circuit breaker equipped with a grading capacitor, the residual flux characteristic cannot be considered as constant. A source voltage will feed the deenergized transformer system through the grading capacitor, which will change the residual flux level and let oscillations appear. It follows that the optimal re-energization targets change and inrush currents might not be optimally minimized. Further, transient voltages based on line failures can influence the residual flux through a grading capacitor as well. At first, this paper evaluates the influence of a grading capacitor on the residual flux characteristic analytically. Further, measurements of two transformer systems at a varied de-energization instant and for different grading capacitors provide actual information for the development of future controller systems.

  18. 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.

  19. The Influence of Contact Space on Arc Commutation Process in Air Circuit Breaker

    Science.gov (United States)

    Niu, Chunping; Ding, Juwen; Yang, Fei; Dong, Delong; Rong, Mingzhe; Xu, Dan

    2016-05-01

    In this paper, a 3D magneto-hydrodynamic (MHD) arc simulation model is applied to analyze the arc motion during current interruption in a certain air circuit breaker (ACB). The distributions of pressure, temperature, gas flow and current density of the arc plasma in the arc region are calculated, and the factors influencing the commutation process are analyzed according to the calculated results. Based on the airflow in the arc chamber, the causes of arc commutation asynchrony and the back commutation are investigated. It indicates that a reasonable contact space design is crucial to a successful arc commutation process. To verify the simulation results, the influence of contact space on arc voltage and arc commutation is tested. This research can provide methods and references to the optimization of ACB design. supported by National Key Basic Research Program of China (973 Program) (Nos. 2015CB251002, 6132620303) and National Natural Science Foundation of China (Nos. 51221005, 51377128, 51577144), and Science and Technology Project Through Grid State Corporation (No. SGSNKYOOKJJS1501564)

  20. Calculation of Nozzle Ablation During Arcing Period in an SF6 Auto-Expansion Circuit Breaker

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junmin; LU Chunrong; GUAN Yonggang; LIU Weidong

    2016-01-01

    The nozzle ablation process is described as two phases of heat and ablation in the interruption for an SF6 circuit breaker in this paper.Their mathematical models are established with the Fourier heat conduction differential equation respectively.The masses of nozzle ablation with different arc durations and arc currents are calculated through the model of the nozzle ablation combined with an MHD (magneto-hydrodynamic) arc model.The time of the temperature rise on the inner surface of the nozzle under a given energy flux and of reaching the pyrolysis temperature under different energy fluxes is respectively analyzed.The relations between the mass of nozzle ablation and breaking current and arc duration are obtained.The result shows that the absorbing energy process before the nozzle ablation can be neglected under the condition of the energy flux entering into nozzle q > 109 W/m2.The ablation is the severest during the high-current phase and the ablation mass increases rapidly with the breaking current and with arc duration respectively.

  1. Using a Field Trip Inventory to Determine If Listening to Elementary School Students' Conversations, While on a Zoo Field Trip, Enhances Preservice Teachers' Abilities to Plan Zoo Field Trips

    Science.gov (United States)

    Patrick, Patricia; Mathews, Cathy; Tunnicliffe, Sue Dale

    2013-01-01

    This study investigated whether listening to spontaneous conversations of elementary students and their teachers/chaperones, while they were visiting a zoo, affected preservice elementary teachers' conceptions about planning a field trip to the zoo. One hundred five preservice elementary teachers designed field trips prior to and after…

  2. Babcock and Wilcox Owners' Group program: Trip reduction and transient response improvement

    International Nuclear Information System (INIS)

    In 1985, the average trip frequency for the industry was 4.3 trips per plant per year while Babcock ampersand Wilcox (B ampersand W)-designed plants had 4.5 trips. In early 1986, the B ampersand W Owners' Group (B ampersand WOG) established goals to reduce trip frequency and improve posttrip transient response. Through the recommendations of the B ampersand WOG Trip Reduction and Transient Response Improvement Program (TR/TRIP) and other utility initiatives, the trip frequency for the B ampersand WOG plants has been on a progressive downward trend and has been consistently below the industry average since 1986. The successful results in trip reduction for the B ampersand WOG plants are shown. The B ampersand WOG has implemented several programs that have resulted in fewer trips per plant. This success can be attributed to the following: (1) a comprehensive program to evaluate each trip and transient for root-cause determination, define corrective actions, share information, and peer reviews; (2) a broad program to review systems and components that contribute to trips and transients, identify specific recommendations to correct deficiencies, utility commitment to implementation, conduct internal monitoring and indirectly exert peer pressure; (3) an awareness of the goals at all levels in the organization coupled with strong executive-level involvement; and (4) timely implementation of recommendations

  3. Customer satisfaction with individual shopping trip experiences in grocery retailing

    DEFF Research Database (Denmark)

    Esbjerg, Lars; Grunert, Klaus G; Jensen, Birger Boutrup;

    Grocery retailers from Aldi to Wal-Mart strive to satisfy their customers. Grocery shopping is a frequently recurring activity that can provide both utilitarian and hedonic value to customers. Utilitarian value is derived from accomplishing the need that stimulated a particular shopping trip......, whereas hedonic value reflects the potential entertainment and emotional worth associated with the shopping trip. Recognising this duality, in addition to enabling customers to satisfy utilitarian needs related to product-acquisition, grocery retailers increasingly try to offer customers pleasurable...... encounters with that retailer. There are relatively few studies of satisfaction within the grocery retail sector. However, because grocery shopping is a frequently recurring activity that is often routine and task-oriented in nature, and thus dominated by utilitarian rather than hedonic concerns, different...

  4. Analysis of reactor trips originating in balance of plant systems

    Energy Technology Data Exchange (ETDEWEB)

    Stetson, F.T.; Gallagher, D.W.; Le, P.T.; Ebert, M.W. (Science Applications International Corp., McLean, VA (USA))

    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.

  5. Analysis of reactor trips originating in balance of plant systems

    International Nuclear Information System (INIS)

    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

  6. The Big Trip and Wheeler-DeWitt equation

    CERN Document Server

    Yurov, Artyom V; Yurov, Valerian A

    2012-01-01

    Of all the possible ways to describe the behavior of the universe that has undergone a big trip the Wheeler-DeWitt equation should be the most accurate -- provided, of course, that we employ the correct formulation. In this article we start by discussing the standard formulation introduced by Gonz\\'alez-D\\'iaz and Jimenez-Madrid, and show that it allows for a simple yet efficient method of the solution's generation, which is based on the Moutard transformation. Next, by shedding the unnecessary restrictions, imposed on aforementioned standard formulation we introduce a more general form of the Wheeler-DeWitt equation. One immediate prediction of this new formula is that for the universe the probability to emerge right after the big trip in a state with $w=w_0$ will be maximal if and only if $w_0=-1/3$.

  7. 10 years after implementation of TRIPS obligations in India.

    Science.gov (United States)

    Pawar, Mahesh D

    2015-01-01

    The Patent (Amendment) Act of 2005 enforced after TRIPS raises many issues which hinder growth of Indian pharma companies. To tackle this, Indian pharma companies doubled their R&D expenditure and became significant players in global generic drug market. Indian pharmaceutical companies, which predominantly focused on import-oriented market, shifted to research-based approach by signing various agreements with MNCs that led to M&A and technology transfer. At the same time growth in R&D activities increased ANDA and DMF filing in the USA and Europe. Companies also kept their social responsibility by selling medicines at affordable price to patients. This paper highlights the changing business scenario of Indian pharmaceutical companies to counteract various issues evolved from new patent regime after TRIPS. PMID:26030078

  8. Microstructure Evolution during Friction Stir Spot Welding of TRIP steel

    DEFF Research Database (Denmark)

    Lomholt, Trine Colding

    Transformation Induced Plasticity (TRIP) steels have been developed for automotive applications due to the excellent high strength and formability. The microstructure of TRIP steels is a complex mixture of various microstructural constituents; ferrite, bainite, martensite and retained austenite...... deteriorating the uniform elongation. The unique deformation properties can be exploited in automotive applications for crash resistant parts due to the high energy absorption, thus improving passenger safety. Furthermore, the high strength and good formability permits the application of thinner sheet material...... Welding (FSSW) is investigated. The aim of the study is to assess whether high quality welds can be produced and, in particular, to obtain an understanding of the microstructural changes during welding. The microstructure of the welded samples was investigated by means of reflected light microscopy...

  9. Assuring microstructural homegeniety in dual phase and trip steels

    Energy Technology Data Exchange (ETDEWEB)

    Rivera-Diaz-del-Castillo, P.E.J.; Zwaag, S. van der [Faculty of Aerospace Engineering, Delft Univ., Delft (Netherlands)

    2004-11-01

    The presence of ferrite/pearlite bands in dual phase and TRIP assisted steels is a consequence of microchemical segregation which causes mechanical properties anisotropy. Such inhomogeneous phase distribution produces a lowering of the mechanical properties such as fracture behaviour. This anisotropy is commonly not accounted in micromechanics computations which often assume a random distribution of phases in the solid. The present paper deals with an integral model for this undesirable band formation accounting for the solute segregation caused by solidification, microcomponent diffusion present in the austenitisation process, and the nucleation of the transformed phase in segregated regions. In the present work, the model was applied to two industrial grade dual phase steels and two TRIP assisted steels. The influence of such parameters on band formation is summarised in a number of ''band prevention plots'', which are aimed at providing the optimum processing conditions for ferrite/pearlite band prevention. (orig.)

  10. Visiting the USSR: a trip of a lifetime.

    Science.gov (United States)

    Brown, Geraldine

    2012-01-01

    To Russia, who me? That is actually how it all began. A decade or more ago, I had the opportunity to visit what was then known as the Union of Soviet Socialist Republics (USSR), Russia. Although, this place held high priority on my list of places to go, I never thought such a trip was within my reach. This idea was quite fascinating to me because of the events that did happen there, including the Russian space ship Sputnik and the dog, the high stepping military officers, Red Square and the St. Basil's Cathedral. After reading a lot about Russia, I thought it would be great to see a clean place, where it was unlawful to throw paper on the streets, and ride in public transportation such as the buses, taxis and the subway system, which were immaculately clean. It was an exciting trip, one, I will always remember, but would be a difficult adjustment to make, to live. PMID:22774358

  11. Improvement of failure protection for high voltage side circuit breaker of 220 kV transformer%220kV变压器高压侧断路器失灵保护的改进

    Institute of Scientific and Technical Information of China (English)

    郑春生

    2016-01-01

    Failure protection of Shengli Oilfield 220 kV substation main transformer circuit breaker, its typical configuration cannot effectively isolate the fault point, in some atypical failure,the main transformer for a long time by the impact of short-circuit current,seriously affect the power system stability and safety. The failure protection action nodes and mother difference protection action nodes and the corresponding non electric starter relay series, when startup failure protection, the corresponding node closed, start relay, to direct trip-ping of main transformer with three side of the switch. Using this improved scheme, 3 of Shengli Oilfield 220 kV substation main transformer failure protection has been improved, reduces the possibility of 220 kV Main Transformer be impact by the fault current, guarantee the safe and stable operation of power grids.%胜利油田220 kV变电站主变断路器失灵保护中的典型配置不能有效隔离故障点,在一些非典型故障中,会使主变长时间受到短路电流冲击,严重影响电力系统稳定性和安全性.为此,将失灵保护动作节点和母差保护动作节点与相应的非电量启动继电器串联,当失灵保护启动时,相应节点闭合,启动继电器,进而直接跳开主变三侧开关.应用此改进方案,对胜利油田3座220 kV变电站的主变失灵保护进行了完善,降低了220 kV主变压器受到故障电流冲击的可能性,保障了电网安全、稳定运行.

  12. Numerical Prediction on the Thermal Interrupting Capability of HV SF6 Gas Circuit Breakers%Numerical Prediction on the Thermal Interrupting Capability of HV SF6Gas Circuit Breakers

    Institute of Scientific and Technical Information of China (English)

    MU Jingwei; GUO Jin; DENG Xiang'e

    2013-01-01

    The design technology for HV SF6 gas circuit breakers is very demanding.A numerical method for prediction of the thermal interruption capability of SF6 gas circuit breakers is established based on the two-dimensional magneto-hydrodynamic (MHD) model and a commercial CFD(computational fluid dynamics) software,FLUENT.Nozzle ablation effect is considered by introducing an independent mass conservation equation for the ablated material to the overall conservation equations of mass,momentum,and energy.The ohmic heating and the radiation of the electric arc are considered in the model by adding relevant source terms.To predict the thermal interruption capability,the arc conductance 200 ns before current zero is used as an indicator.The CFD model is applied for the high current arcing phase,and Mayr arc model is used near the current zero period.The arc conductance at 200 ns before current zero(G200) for various arcing periods are computed by the present method.It shows that there exist a limit of the G200.For those whose arcing periods are within the arcing window,the related G200 are below the limit,therefore result a successful current interruption,and vice versa.The validation of the developed computer simulation tool is therefore verified.The numerical prediction by the simulation tool is verified by the direct interrupting test of 550 kV gas circuit breaker (GCB).The developed computer simulation tool was applied in the design of a 550 kV GCB.Significant benefits have been achieved in terms of both the cost saving and shorten of the development cycle.

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

    OpenAIRE

    Petter Næss

    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...

  14. Press formability YAG laser welded TRIP/DP tailored blanks

    Science.gov (United States)

    Nagasaka, A.; Sugimoto, K. I.; Kobayashi, M.; Makii, K.; Ikeda, S.

    2004-06-01

    In the present work, to improve the press formability of the combination of the TRIP steel and ferrite-martensite dual-phase (DP) steel, the mechanical properties and press formability (stretch-formability) of YAG laser welded TRIP/DP tailored blanks were investigated. An as-cold-rolled sheet steel with the chemical composition of (0.1 0.3)C 1.5Si 1.5Mn (mass%) was used in this study. For comparison, 0.14C 0.22Si 1.78Mn (mass%) DP steel was also prepared. The quenched DP steel is called MDP0, and the tempered MDP0 steel is called MDP4. For butt welding, the blank obtained after the heat treatment was cut using a fine cutter, and YAG laser processing equipment was used. The press formability was evaluated from the maximum stretch-height (Hmax). Tensile tests and stretch forming tests have been conducted for laser butt welded joints obtained from the combination of the different steel. The Hmax value of the MDP0 steel was not controlled at the strength level of the DP steel, and was not different from the Hmax value of the MDP4 steel. It is thought that this was assisted to TRIP of the TDP steel because the tensile strength of the TDP steel is consequentially lower than that of the MDP0 steel. High ductility and the high stretch-formability were able to be secured by the high strength TRIP/DP tailored blanks.

  15. Equilibrium analysis of trip chains in congested networks

    OpenAIRE

    Heydecker, B.

    2004-01-01

    In this paper, we develop a model of travel in a chain of trips joining several locations througha congested network. We develop a microscopic analysis of individual benefits obtained byspending time at each of the locations and costs incurred through travel between them. This iscombined with a macroscopic equilibrium model of travel during congested peak periods toshow how individuals? travel choices are influenced by the congestion that result fromcorresponding choices made by others. We sh...

  16. EFFECT OF CHEMICAL COMPOSITION ON RETAINED AUSTENITE IN TRIP STEEL

    Institute of Scientific and Technical Information of China (English)

    Y. Chen; X. Chen; Q.F. Wang; G.L. Yuan; C.Y. Li; X.Y. Li; Y.X. Wang

    2002-01-01

    The systematic chemical compositions including common C, Si, Mn, Al, and micro- alloying elements of Ti and Nb were designed for high volume fraction of retained austenite as much as possible. The thermo-cycle experiments were conducted by using Gleeble 2000 thermo-dynamic test machine for finding the appropriate composition. The experimental results showed that chemical composition had a significant effect on retained austenite, and the appropriate compositions were determined for commercial production of TRIP steels.

  17. A turbine trip transient analyses with TRAC-BF1

    International Nuclear Information System (INIS)

    This paper reports a turbine trip transient analysis for a BWR/5 nuclear power plant performed with TRAC-BF1 code, a well-known best-estimate code used for transient analyses of boiling water reactors. The work undertook an evaluation of several safety parameters, such as dome pressure rise, maximum temperature in the fuel, maximum reactor power, total reactivity, and others. 2 refs., 7 figs., 3 tabs

  18. Prediction of the mechanical behaviour of TRIP steel

    OpenAIRE

    Perdahcioglu, E.S.; Geijselaers, H.J.M.; Tekkaya, A. E.; Hirt, G.

    2011-01-01

    TRIP steel typically contains four different phases, ferrite, bainite, austenite and martensite. During deformation the metastable retained austenite tends to transform to stable martensite. The accompanying transformation strain has a beneficial effect on the ductility of the steel during forming. By changing the alloy composition, the rolling procedure and the thermal processing of the steel, a wide range of different morphologies and microstructures can be obtained. Interesting parameters ...

  19. Meaningful Field Trip in Education of Renewable Energy Technologies

    OpenAIRE

    Hasan Said Tortop

    2013-01-01

    Renewable energy sources, in terms of countries‟ obtaining their energy needs from clean and without harming the environment is becoming increasingly important. This situation also requires improving the quality of science education will be given in this field. In this activity, in a field trip to the center for the renewable energy resources technologies, the application of learning cycle model appropriate for constructivist approach is shown. In the example of solar chimney activity accordi...

  20. 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.

  1. Urban association rules: uncovering linked trips for shopping behavior

    CERN Document Server

    Yoshimura, Yuji; Hobin, Juan N Bautista; Ratti, Carlo; Blat, Josep

    2016-01-01

    In this article, we introduce the method of urban association rules and its uses for extracting frequently appearing combinations of stores that are visited together to characterize shoppers' behaviors. The Apriori algorithm is used to extract the association rules (i.e., if -> result) from customer transaction datasets in a market-basket analysis. An application to our large-scale and anonymized bank card transaction dataset enables us to output linked trips for shopping all over the city: the method enables us to predict the other shops most likely to be visited by a customer given a particular shop that was already visited as an input. In addition, our methodology can consider all transaction activities conducted by customers for a whole city in addition to the location of stores dispersed in the city. This approach enables us to uncover not only simple linked trips such as transition movements between stores but also the edge weight for each linked trip in the specific district. Thus, the proposed methodo...

  2. C16, a novel advanced glycation endproduct breaker, restores cardiovascular dysfunction in experimental diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Gang CHENG; Li-li WANG; Wen-sheng QU; Long LONG; Hao CUI; Hong-ying LIU; Ying-lin CAO; Song LI

    2005-01-01

    Aim: Advanced glycation endproducts (AGE) have been implicated in the pathogenesis of diabetic complications, including diabetic cardiovascular dysfunction.3-[2-(4-Bromo-phenyl)- 1-methyl-2-oxo-ethyl]-4,5,6,7-tetrahydro-benzothiazol-3-ium bromide (C16), a novel AGE breaker, was investigated for its effects on the development of cardiovascular disease in diabetic rats. Methods: Rats that had streptozotocin-induced diabetes for 12 weeks were divided into groups receiving C16 or vehicle by gavage. Results: In hemodynamic studies of the left ventricle,C16 treatment (25 or 50 mg/kg) for 4 weeks resulted in a significant increase in left ventricular systolic pressure, +dp/dtmax, and -dp/dtmax as compared with vehicletreated diabetic rats. Furthermore, in hemodynamic studies of the cardiovascular system, C16 (12.5, 25, or 50 mg/kg) treatment for 4 weeks resulted in a dosedependent and significant increase in cardiac output, a reduction of total peripheral resistance, and an increase in systemic arterial compliance when compared with vehicle-treated diabetic rats. Biochemical studies showed that C16 treatment also resulted in a significant decrease in immunoglobulin G-red blood cell surface crosslink content and an increase in collagen solubility. Morphological and immunohistochemical examinations indicated that C 16 was able to prevent increases of the collagen type Ⅲ/Ⅰ ratio in the aorta and decrease the accumulation of AGE in the aorta. Conclusion: C16 has the ability to reduce AGE accumulation in tissues in vivo, and can restore diabetes-associated cardiovascular disorders in rats. This provides a potential therapeutic approach for cardiovascular disease associated with diabetes and aging in humans.

  3. Pre-trip vs. post-trip destination image variations: A case of inbound tourists to Tanzania

    OpenAIRE

    Jani, Dev; Nguni, Winnie

    2016-01-01

    Despite the conceptual indications of destination image to vary with factors like travel status and tourist behaviour, there are few studies that have empirically researched the variations in destination image particularly in emerging destinations like those in Africa. This study aimed at testing the variation of pre- and post trip destination image held by inbound travellers to Tanzania. Four hypotheses were defined to test variation of destination image with travel status, destination famil...

  4. Chelation: a fundamental mechanism of action of AGE inhibitors, AGE breakers, and other inhibitors of diabetes complications.

    Science.gov (United States)

    Nagai, Ryoji; Murray, David B; Metz, Thomas O; Baynes, John W

    2012-03-01

    This article outlines evidence that advanced glycation end product (AGE) inhibitors and breakers act primarily as chelators, inhibiting metal-catalyzed oxidation reactions that catalyze AGE formation. We then present evidence that chelation is the most likely mechanism by which ACE inhibitors, angiotensin receptor blockers, and aldose reductase inhibitors inhibit AGE formation in diabetes. Finally, we note several recent studies demonstrating therapeutic benefits of chelators for diabetic cardiovascular and renal disease. We conclude that chronic, low-dose chelation therapy deserves serious consideration as a clinical tool for prevention and treatment of diabetes complications.

  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....... 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...

  6. Field Experiments on 10 kV Switching Shunt Capacitor Banks Using Ordinary and Phase-Controlled Vacuum Circuit Breakers

    OpenAIRE

    Wenxia Sima; Mi Zou; Qing Yang; Ming Yang; Licheng Li

    2016-01-01

    During the switching on/off of shunt capacitor banks in substations, vacuum circuit breakers (VCBs) are required to switch off or to switch on the capacitive current. Therefore, the VCBs have to be operated under a harsh condition to ensure the reliability of the equipment. This study presents a complete comparison study of ordinary and phase-controlled VCBs on switching 10 kV shunt capacitor banks. An analytical analysis for switching 10 kV shunt capacitor banks is presented on the basis of ...

  7. Interruption of a dry-type transformer in no-load by a vacuum circuit-breaker

    Science.gov (United States)

    Vandenheuvel, W. M. C.; Daalder, J. E.; Boone, M. J. M.; Wilmes, L. A. H.

    1983-08-01

    Overvoltages generated during interruption of a dry type delta-star connected transformer in no load by a vacuum breaker were studied. During interruption of inrush current 37% of the phase-to-ground overvoltages were 5 pu, and 6% 7 pu. Comparison of experimental and theoretical results using Boyle's model shows no discrepancy for inrush currents and clean overvoltages from the steady-state interruption. Overvoltages due to repetitive reignitions (not covered by Boyle's model) are higher than the calculated values during steady-state switching.

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

    OpenAIRE

    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 parameters in the network was evaluated during a fault in the onshore substation. The rate of rise of recovery voltage (RRRV) and the maximum crest voltage (Uc) of the TRV across the GIS CB were compar...

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

    Institute of Scientific and Technical Information of China (English)

    Rong Mingzhe; Yang Qian; Fan Chunduo

    2005-01-01

    A new magnetic hydro-dynamics (MHD) model of arc in H.V. auto-expansion SF6circuit 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.

  10. 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

    parameters in the network was evaluated during a fault in the onshore substation. The rate of rise of recovery voltage (RRRV) and the maximum crest voltage (Uc) of the TRV across the GIS CB were compared against the standard values based on the type test results from the GIS. The investigations were......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...

  11. 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…

  12. 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

  13. Predictive Process Optimization for Fracture Ductility in Automotive TRIP Steels

    Science.gov (United States)

    Gong, Jiadong

    In light of the emerging challenges in the automotive industry of meeting new energy-saving and environment-friendly requirements imposed by both the government and the society, the auto makers have been working relentlessly to reduce the weight of automobiles. While steel makers pushed out a variety of novel Advanced High Strength Steels (AHSS) to serve this market with new needs, TRIP (Transformation Induced Plasticity) steels is one of the most promising materials for auto-body due to its exceptional combination of strength and formability. However, current commercial automotive TRIP steels demonstrate relatively low hole-expansion (HE) capability, which is critical in stretch forming of various auto parts. This shortcoming on ductility has been causing fracture issues in the forming process and limits the wider applications of this steel. The kinetic theory of martensitic transformations and associated transformation plasticity is applied to the optimization of transformation stability for enhanced mechanical properties in a class of high strength galvannealed TRIP steel. This research leverages newly developed characterization and simulation capabilities, supporting computational design of high-performance steels exploiting optimized transformation plasticity for desired mechanical behaviors, especially for the hole-expansion ductility. The microstructure of the automotive TRIP sheet steels was investigated, using advanced tomographic characterization including nanoscale Local Electrode Atom Probe (LEAP) microanalysis. The microstructural basis of austenite stability, the austenite carbon concentration in particular, was quantified and correlated with measured fracture ductility through transformation plasticity constitutive laws. Plastic flow stability for enhanced local fracture ductility at high strength is sought to maintain high hole-expansion ductility, through quantifying the optimal stability and the heat-treatment process to achieve it. An additional

  14. 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)

    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

  15. Summary of CIGRE 13.06 Working Group world wide reliability data and maintenence cost data on high voltage circuit breakers above 63 kV

    Energy Technology Data Exchange (ETDEWEB)

    Colombo, E.; Dialynas, E.; Heising, C.; Janssen, A.; Lanz, W.

    1995-06-01

    A summary is given of the most significant reliability data and maintenance cost data from the two CIGRE 13.06 Working Group world wide reliability surveys of the reliabilityof high voltage circuit breakers 63 kV and above. The first enquiry covered the years 1974 thru 1977 and included all interrupting technologies. The second enquiry covered the years 1988 thru 1991 and only included single pressure SF6 breakers. A description is given of the scope and objectives of the CIGRE 13.06 Working Group. A brief description is given of some of the highlights from their studies.

  16. 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.

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

    International Nuclear Information System (INIS)

    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 ft2 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)

  18. Factors that influence learning during a scientific field trip in a natural environment

    Science.gov (United States)

    Orion, Nir; Hofstein, Avi

    This study deals with the educational effectiveness of field trips. The main purpose was to obtain insight concerning factors that might influence the ability of students to learn during a scientific field trip in a natural environment. The research was conducted in the context of a 1-day geologic field trip by 296 students in Grades 9 through 11 in high schools in Israel. The study combined qualitative and quantitative research methods. Data were collected from three different sources (student, teacher, and outside observer) in three stages (before, after, and during the field trip). Using observations and questionnaires we investigated: a) the nature of student learning during the field trip, b) student attitudes toward the field trip, and c) changes in student knowledge and attitudes after the field trip. Our findings suggest that the educational effectiveness of a field trip is controlled by two major factors: the field trip quality and the Novelty space (or Familiarity Index). The educational quality of a field trip is determined by its structure, learning materials, and teaching method, and the ability to direct learning to a concrete interaction with the environment. The novelty space consists of three prefield variables: cognitive, psychological, and geographic. The learning performance of students whose Novelty Space was reduced before the field trip was significantly higher than that of students whose Novelty Space had not been so reduced. Thus, the former group gained significantly higher achievement and attitude levels. It is suggested that a field trip should occur early in the concrete part of the curriculum, and should be preceded by a relatively short preparatory unit that focuses on increasing familiarity with the learning setting of the field trip, thereby limiting the Novelty Space factors.Received: 23 March 1993; Revised: 24 January 1994;

  19. 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.

  20. Field trips and their effect on student achievement in and attitudes toward science: A comparison of a physical versus a virtual field trip to the Indian River Lagoon

    Science.gov (United States)

    Garner, Lesley Cochran

    The purpose of this study was to determine the effect of physical and virtual field trips on students' achievement in estuarine ecology and their attitudes toward science. The study also assessed the effect of students' learning styles, the interaction between group membership and learning styles, and the effect of group membership on students' ability to answer questions at different levels of Bloom's (1956) taxonomy. Working with a convenient sample of 67 freshmen and sophomore non-science majors, students were randomly assigned to one of two treatment groups (physical, n = 32 and virtual, n = 35). Prior to treatment, students' learning styles were determined, students were pre-assessed on the two targeted measures, and all students attended four consecutive, in-class, 75-minute lectures on estuarine ecology and the Indian River Lagoon (IRL). Pre-assessed data indicated no significant differences between the groups on the two dependent measures. On the weekend following the lecture series, the physical field trip group engaged in a set of predetermined activities at the IRL for 2 hours in the morning. Later that afternoon, the virtual field trip group participated in a 2-hour virtual trip to the IRL that exactly matched the physical field trip activities. This virtual trip incorporated the CD-ROM The Living Lagoon: An Electronic Field Trip. Following each trip, students were post-assessed using the same pre-assessment instruments. MANCOVA results indicated no significant differences on all research factors (i.e., group membership, learning style, and group-learning style interaction). Data analysis also revealed that there was no significant effect of group membership on students' ability to answer questions at different levels of Bloom's taxonomy. These findings imply that educators can integrate virtual field trips that are structured in the same manner as their corresponding physical field trips without significantly impacting student achievement or attitudes.

  1. 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.

  2. Approach for electrodynamic force for compensation in low voltage circuit breaker WP 630-1.2 type

    Institute of Scientific and Technical Information of China (English)

    LU Na; XU L.J.; Miedzi(n)ski B.

    2007-01-01

    Undesirable repulsive force between contact members due to both a current path shrink near a real contact area and/or so-called pinch effect is particularly onerous for power switch applications, and results in either contact floating or bouncing which are associated with an electric arc following contact welding. This problem is of great importance for any circuit breaker especially for compact low voltage vacuum circuit breakers. To avoid contact floating at closure and during any inrush current under short circuit conditions, the electrodynamic repulsive force can be employed successfully if we use a special compensation system flexibly combined with the contact itself. However to select and design the compensation system properly, its efficiency has to be known. This paper presents an approach to obtain the electrodynamic force value depending on different shaped (rectangular,square, circle and arch) copper plates used in the compensator by using ANSYS for current values 40 kA RMS. Curve-fitting was done according to the calculating results, the optimization designing of compensation unit is based on them.

  3. 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.

  4. Development of RPS trip logic based on PLD technology

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong Gyun; Lee, Dong Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-08-15

    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.

  5. Active commuting to school in Portuguese adolescents: Using PALMS to detect trips

    DEFF Research Database (Denmark)

    Pizarro, Andreia Nogueira; Schipperijn, Jasper; Andersen, Henriette Bondo;

    2016-01-01

    Abstract The declining levels of physical activity (PA) have led to active commuting to school (ACS) being seen as a key strategy to increase PA levels in school-aged children. In Portugal, no data exists on the patterns of this behavior, an essential step for developing evidence......-based and effective interventions. The purpose of this study is to explore the travel to school behavior using an objective methodology. Methods 155 adolescents (mean age 15.9±1.1 years) wore an accelerometer and a GPS for 7 consecutive days. Home and school addresses were geocoded to identify home-school trips....... The web-based tool PALMS was used to combine GPS and accelerometer data, categorize Moderate to Vigorous Physical Activity (MVPA) and classify trip mode of home-school trips into: walking, bicycling or vehicle. Results 609 trips were identified as home-school trips. Walking was the most frequent trip mode...

  6. 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...... 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....

  7. 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.

  8. Study of nuclear power plant stability. Trip criteria

    International Nuclear Information System (INIS)

    The influence that nuclear power plants and high voltage power systems have on each other when confronted by disturbances in the offsite network may lead, due to dynamic effects, to plant trip. It is therefore necessary to study the disturbances in the network and the effects on plant equipment by means of dynamic simulations which evaluate the unit protection system and the auxiliary services so as to obtain maximum unit availability without jeopardizing its safety. These studies can be conducted since there are models and software tools capable of simulating dynamic behaviour of the electric system, including the excitation systems and specific speed governors obtainment of valid. (author)

  9. 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.

  10. Effect of Thermomechanical Processing on Microstructures of TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    TANG Zheng-you; DING Hua; DU Lin-xiu; DING Hao; ZHANG Xin

    2007-01-01

    In order to control retained austenite, the effect of hot deformation in the intercritical region on the microstructure of hot-rolled transformation-induced plasticity (TRIP) steel was studied on a Gleeble 1500 hot simulator. Compressive strains varying in amounts from 0 to 60% were imposed in the intercritical region, and effects on the formation of polygonal ferrite, carbide-free bainite and retained austenite were determined. With increasing the hot deformation amount and the ferrite content and decreasing the carbide-free bainite content, the volume fraction of retained austenite decreases. Increased dislocation density, grain refinement of ferrite and carbon enrichment are the main factors which control retained austenite stability.

  11. The Scope of Gene Patent Protection and the TRIPS Agreement

    DEFF Research Database (Denmark)

    Sommer, Tine

    2007-01-01

    The Scope of Gene Patent Protection and the TRIPS Agreement - An Exclusively Nondiscriminatory Approach?   Gene patenting in Europe has provoked much debate both before and since the adoption of Directive 98/44/EC on the legal protection of biotechnological inventions. Some of the major points...... of discussion have been focused on the scope of protection (e.g. purpose-bound protection) and gene patents being subject to a specific DNA regime on patent rights. The Directive can be interpreted as favouring such a solution, but so far the European Commission has decided neither to support nor reject...

  12. Recrystallization Modelling of Hot Deformed Si-Mn TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    ZHU Li-juan; WU Di; ZHAO Xian-ming

    2007-01-01

    By means of hot compression single and double hit experiments, the kinetics of dynamic and static recrystallization in hot-rolled Si-Mn TRIP steel was studied, and the emphasis was put on the influence of high silicon content. The results show that the calculated parameters are consistent with the experimental ones, and addition of silicon retards both dynamic and static recrystallization as well as increases the flow stress of austenite, and the non-recrystallization zone can be enlarged by increasing the silicon contents.

  13. Characterization of micro machined surface from TRIP/TWIP steels

    Directory of Open Access Journals (Sweden)

    Smaga M.

    2015-01-01

    Full Text Available In this contribution micro machining induced changes in surface morphology, including phase transformation from fcc-austenite into hcp- and bcc-martensite as well as defined surface topography of TRIP/TWIP steel was characterized by scanning electron microscopy using electron backscatter diffraction (EBSD technique. For this, applying micro milling and micro grinding processes with tool diameter of 45 µm, structures were machined into flat specimen surfaces of X30MnAl17–1 steel in defined areas previously characterized by EBSD.

  14. The trip of the tip: understanding the growth cone machinery.

    Science.gov (United States)

    Lowery, Laura Anne; Van Vactor, David

    2009-05-01

    The central component in the road trip of axon guidance is the growth cone, a dynamic structure that is located at the tip of the growing axon. During its journey, the growth cone comprises both 'vehicle' and 'navigator'. Whereas the 'vehicle' maintains growth cone movement and contains the cytoskeletal structural elements of its framework, a motor to move forward and a mechanism to provide traction on the 'road', the 'navigator' aspect guides this system with spatial bias to translate environmental signals into directional movement. The understanding of the functions and regulation of the vehicle and navigator provides new insights into the cell biology of growth cone guidance.

  15. Nutrient/serum starvation derived TRIP-Br3 down-regulation accelerates apoptosis by destabilizing XIAP

    Science.gov (United States)

    Lee, Soonduck; Jeong, Dongjun; Yang, Young; Kim, Keun-Il; Lim, Jong-Seok; Cheon, Chung-Il; Kim, Changjin; Kang, Young-Sook; Lee, Myeong-Sok

    2015-01-01

    TRIP-Br3 and TRIP-Br1 have shown to have important biological functions. However, the function of TRIP-Br3 in tumorigenesis is not well characterized compared to oncogenic TRIP-Br1. Here, we investigated the function of TRIP-Br3 in tumorigenesis by comparing with that of TRIP-Br1. Under nutrient/serum starvation, TRIP-Br3 expression was down-regulated slightly in cancer cells and significantly in normal cells. Unexpectedly, TRIP-Br1 expression was greatly up-regulated in cancer cells but not in normal cells. Moreover, TRIP-Br3 activated autophagy while TRIP-Br1 inactivated it under serum starvation. In spite of different expression and roles of TRIP-Br3 and TRIP-Br1, both of them alleviate cell death by directly binding to and stabilizing XIAP, a potent apoptosis inhibitor, through blocking its ubiquitination. Taken together, we propose that TRIP-Br3 primarily activates the autophagy and suppresses apoptosis in nutrient sufficient condition. However, the prolonged extreme stressful condition of nutrient starvation causes a dramatic decrease of TRIP-Br3, which in turn induces apoptosis by destabilizing XIAP. Up-regulated TRIP-Br1 in cancer cells compensates this effect and delays apoptosis. This can be explained by the competitive alternative binding of TRIP-Br3 and TRIP-Br1 to the BIR2 domain of XIAP. In an extended study, our immunohistochemical analysis revealed a markedly lower level of TRIP-Br3 protein in human carcinoma tissues compared to normal epithelial tissues, implying the role of TRIP-Br3 as a tumor suppressor rather than onco-protein. PMID:25691055

  16. Linking Geographic Information Systems and Trip Reduction: Success and Failure in a Pilot Application

    OpenAIRE

    Burns, Elizabeth K.

    1993-01-01

    Travel demand management policies are the focus of a national debate on ways to limit the growth of local highway congestion and improve urban air quality (Bae, 1993; Orski, 1989). One innovative approach, trip reduction programs, requires changes in individual travel behavior, usually in journey to work trips. While precise local goals and requirements vary, major trip reduction programs focus on large employers who must persuade drive-alone employees to increase vehicle occupancy, limit mil...

  17. 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...

  18. Constraint Programming Formulation for the Elevator Trip Origin-Destination Matrix Estimation Problem

    OpenAIRE

    Kuusinen, Juha-Matti; Malapert, Arnaud

    2014-01-01

    We present a constraint programming formulation for the elevator trip origin-destination matrix estimation problem, and propose different approaches to solve the problem. An elevator trip consists of successive stops in one direction of travel with passengers inside the elevator. It can be defined as a directed network, where the nodes correspond to the stops on the trip, and the arcs to the possible origins and destinations of the passengers boarding and alighting at the stops. The goal is t...

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

    OpenAIRE

    Kuosmanen, Timo; Nillesen, Eleonora; Wesseler, Justus

    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 offset by a shift in the estimated demand curve. Still, ignoring MDT can greatly underestimate or overestimate the CS. In addition, we demonstrate that there is a sound theoretical basis for using prefe...

  20. Design of Thermo Mechanicaln Processing and Transformation Behaviour of Bulk Si-Mn Trip Steel

    OpenAIRE

    J. Zrnik; Mamuzić, I.; Lukaš, P.; Muransky, O.; Jenčuš, P.; Novy, Z.

    2006-01-01

    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 ...

  1. Effect of Aluminum and Silicon on Transformation Induced Plasticity of the TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    Lin LI; B.C. De Cooman; P. Wollants; Yanlin HE; Xiaodong ZHOU

    2004-01-01

    With the sublattice model, equilibrium compositions of ferrite (α) and austenite (γ) phases, as well as the volume percent of austenite (γ) at 780℃ in different TRIP steels were calculated. Concentration profiles of carbon, Mn, Al and Si in the steels were also estimated under the lattice fixed frame of reference so as to understand the complex mechanical behavior of TRIP steels after different isothermal bainitic transformation treatments. The effect of Si and Mn on transformation induced plasticity (TRIP) was discussed according to thermodynamic and kinetic analyses. It is recognized that Al also induces phase transformation in the steels but its TRIP effect is not as strong as that of Si.

  2. The E3 ubiquitin ligase activity of Trip12 is essential for mouse embryogenesis.

    Directory of Open Access Journals (Sweden)

    Masashi Kajiro

    Full Text Available Protein ubiquitination is a post-translational protein modification that regulates many biological conditions. Trip12 is a HECT-type E3 ubiquitin ligase that ubiquitinates ARF and APP-BP1. However, the significance of Trip12 in vivo is largely unknown. Here we show that the ubiquitin ligase activity of Trip12 is indispensable for mouse embryogenesis. A homozygous mutation in Trip12 (Trip12(mt/mt that disrupts the ubiquitin ligase activity resulted in embryonic lethality in the middle stage of development. Trip12(mt/mt embryos exhibited growth arrest and increased expression of the negative cell cycle regulator p16. In contrast, Trip12(mt/mt ES cells were viable. They had decreased proliferation, but maintained both the undifferentiated state and the ability to differentiate. Trip12(mt/mt ES cells had increased levels of the BAF57 protein (a component of the SWI/SNF chromatin remodeling complex and altered gene expression patterns. These data suggest that Trip12 is involved in global gene expression and plays an important role in mouse development.

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

    Science.gov (United States)

    Alon, Nirit Lavie; Tal, Tali

    2016-07-01

    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.

  4. 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 fir

  5. Circuit-Breaker Lightning Accident Analysis Under Electrified State%热备用状态下的断路器雷击事故分析

    Institute of Scientific and Technical Information of China (English)

    王乃会; 邢大鹏; 汪德荣; 曾丽

    2012-01-01

    Via analysis to a burnt-down circuit-breaker accident taking place after certain substation undergoing lightning overvoltage, the main cause of circuit breakers undergoing lightning overvoltage damage under electrified state was that overvoltage all round radiation took place at the end of open circuit to make overvoltage raise in great scale. There are two ways such as to raise a circuit breaker itself with standing overvoltage capacity, to strengthen overvoltage protection and to strengthen safety and reliability of circuit breakers.%通过对某变电站遭受雷击过电压后发生的断路器烧毁事故进行分析,得出处于热备用状态下的断路器遭受雷电过电压损坏的主要原因是过电压在开路末端发生过电压全发射,造成过电压大幅度提高。可通过提高断路器本身耐受过电压能力和加强过电压保护两方面来加强断路器的安全性和可靠性。

  6. Reducing Carbon Emissions from Shopping Trips: Evidence from China

    Directory of Open Access Journals (Sweden)

    Jing Li

    2015-09-01

    Full Text Available With rising income and the emergence of modern shopping centers in urban China, shopping trips by private car becomes more and more common, leading to higher carbon emissions in the transport sector. Encouraging car owners to shift transport mode from private car to public transport could achieve significant emissions reductions. This study estimate carbon emissions savings by shifting from private cars to public transport for shopping trips in urban China, using Shenyang, one of the largest cities in China, as a case study. Our results show that the average carbon emissions per shopper is 426.9 g, and the carbon emissions on weekends is 13% higher than weekdays. Moreover, shoppers travelling by private car emitted five times more carbon emission than those by public transport. We also found that car ownership gradually increased as accessibility to public transport decreased, and that more car owners chose to travel by private cars than public transport in areas with limited access. This study, thus, highlights the potential for high-quality public transport to reduce the transport sector’s carbon emissions in urban China.

  7. 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.

  8. Resolvability in Circulant Graphs

    Institute of Scientific and Technical Information of China (English)

    Muhammad SALMAN; Imran JAVAID; Muhammad Anwar CHAUDHRY

    2012-01-01

    A set W of the vertices of a connected graph G is called a resolving set for G if for every two distinct vertices u,v ∈ V(G) there is a vertex w ∈ W such that d(u,w) ≠ d(v,w).A resolving set of minimum cardinality is called a metric basis for G and the number of vertices in a metric basis is called the metric dimension of G,denoted by dim(G).For a vertex u of G and a subset S of V(G),the distance between u and S is the number mins∈s d(u,s).A k-partition H ={S1,S2,...,Sk} of V(G) is called a resolving partition if for every two distinct vertices u,v ∈ V(G) there is a set Si in Π such that d(u,Si) ≠ d(v,Si).The minimum k for which there is a resolving k-partition of V(G) is called the partition dimension of G,denoted by pd(G).The circulant graph is a graph with vertex set Zn,an additive group ofintegers modulo n,and two vertices labeled i and j adjacent if and only if i - j (mod n) ∈ C,where C C Zn has the property that C =-C and 0(∈) C.The circulant graph is denoted by Xn,△ where A =|C|.In this paper,we study the metric dimension of a family of circulant graphs Xn,3 with connection set C ={1,-n/2,n - 1} and prove that dim(Xn,3) is independent of choice of n by showing that 3 for all n =0 (mod 4),dim(X,n,3) ={ 4 for all n =2 (mod 4).We also study the partition dimension of a family of circulant graphs Xn,4 with connection set C ={±1,±2} and prove that pd(Xn,4) is independent of choice of n and show that pd(X5,4) =5 and 3 forall odd n≥9,pd(Xn,4) ={ 4 for all even n ≥ 6 and n =7.

  9. Incorporating "Virtual" and "Real World" Field Trips into Introductory Geography Modules

    Science.gov (United States)

    Friess, Daniel A.; Oliver, Grahame J. H.; Quak, Michelle S. Y.; Lau, Annie Y. A.

    2016-01-01

    The "field trip" is a key pedagogical tool within geographical education to encourage deep learning, though they are increasingly difficult to implement due to reduced budgets, safety concerns and increasing class sizes. We incorporated three field-learning activities into a large introductory module. A traditional staff-led trip was the…

  10. 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…

  11. Study Abroad Field Trip Improves Test Performance through Engagement and New Social Networks

    Science.gov (United States)

    Houser, Chris; Brannstrom, Christian; Quiring, Steven M.; Lemmons, Kelly K.

    2011-01-01

    Although study abroad trips provide an opportunity for affective and cognitive learning, it is largely assumed that they improve learning outcomes. The purpose of this study is to determine whether a study abroad field trip improved cognitive learning by comparing test performance between the study abroad participants (n = 20) and their peers who…

  12. 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...

  13. 50 CFR 660.232 - Limited entry 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 Limited entry daily trip limit (DTL... limit (DTL) fishery for sablefish. (a) Limited entry DTL fisheries both north and south of 36° N. lat... restrictions and limits of the limited entry daily and/or weekly trip limit (DTL) fishery for...

  14. Promoting Field Trip Confidence: Teachers Providing Insights for Pre-Service Education

    Science.gov (United States)

    Ateskan, Armagan; Lane, Jennie F.

    2016-01-01

    Pre-service teachers need experiences in practical matters as a part of field trip preparations programmes. For 14 years, a private, non-profit university in Turkey has involved pre-service teachers in field trip planning, implementation and evaluation. A programme assessment was conducted through a case study to examine the long-term effects of…

  15. Numerical Analysis of the Arc Plasma in a Simplified Low-voltage Circuit Breaker Chamber with Ferromagnetic Materials

    Institute of Scientific and Technical Information of China (English)

    Wu Yi; Rong Mingzhe; Yang Qian; Hu Guangxia

    2005-01-01

    This paper is devoted to the simulation of the arc plasma in a simplified low-voltage circuit breaker chamber. Based on a group of coupled governing equations, a three-dimensional (3-D) arc plasma model is built and solved by a modified commercial code. Firstly, this paper presents a solution of the stationary state of the arc plasma and discusses the distribution of some parameters throughout the chamber. Secondly, with the ferromagnetic materials included,the balance of the stationary state is broken and a transient course is calculated. In light of the simulation results, the temperature distribution sequence, the arc motion and the plasma jet are then described and analyzed in detail.

  16. Testing of the TriP Chip Running at 132 nsec Using a Modified AFE Board

    International Nuclear Information System (INIS)

    In this note we describe the first set of tests done with a sample of TriP chips that were mounted on a modified AFE board. The modifications consisted of different firmware and the replacement of one power supply switch. The board used was a standard AFEIc board (red type) on which new MCMs (MCMIIs) were mounted. The new MCMs were designed to support the TriP and emulate the SVX for readout when mounted on an AFEIc board. The TriP and the MCMs are described in Ref. [1]. Two versions of the MCMII were designed and built: one (MCMIIb) supports two TriP chips wirebonded directly to the MCM substrate. The other, (MCMIIc) supports one TriP which can be either wirebonded directly or packaged into a standard TQFP surface mount package. Due to space constraints, this MCM can support only 1 TriP. We tested 6 TriP chips on 3 different MCMIIb (MCMIIb-1, MCMIIb-2 and MCMIIb-3) and 2 other TriPs were tested on MCMIIc, one of them with an unpackaged TriP (MCMIIc-1) and the other with a packaged TriP (MCMIIc-2). A set of 10 programable internal registers control the TriP operation, the description of these registers can be found in [1]. Table 1 shows the values used for the tests described in this note. In Ref. [1] there is a description of the signals that are needed to operate the TriP chip. We implemented in a Field Programable Gate Array (FPGA), also part of the MCM, a set of shift registers that allow us to download via the 1553 interface to the AFE board, any desired timing for the signals that the FPGA has to send to the TriP chip. These registers are run with a 121.21 MHz clock (which is 16x the crossing clock and phase locked to it), which means that each bit corresponds to a time interval of 8.25 nsec. Finer control of timing is possible, but this changing the programing of the FPGA and recompiling. The bits downloaded to these shift registers inside the TriP are listed in Table 2

  17. OECD/NRC Boiling Water Reactor Turbine Trip Benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Coddington, P

    2001-11-01

    The meeting was opened by Dr. Paul Coddington from PSI, the Chairman of the Organising and Program Committee of the Workshop. He chaired the Introductory Session 1. The deputy director of the PSI Nuclear Energy Department, Dr. Konstantin Foskolos, welcomed the participants on the behalf of PSI and gave an overview of the nuclear research performed at PSI. The participants introduced themselves and the organisations they represented. 26 participants representing 15 organisations from 8 countries attended the 2nd Workshop. The actual number of participants having submitted results and presentations for the Second Workshop was larger than the number of attendees. The list of participants is provided in Annex 1. Some participants (denoted by stars) had to cancel their trip but they submitted presentations. The agenda, provided as Annex 2, was reviewed and adopted after minor changes. (author)

  18. How travellers’ schedule their trips under uncertain travel times

    DEFF Research Database (Denmark)

    Hjorth, Katrine

    Travel times play an important role when people decide where, when and how much to travel. But travel times are not always predictable from the traveller’s point of view: They may vary from day to day due to demand fluctuations, weather conditions, accidents and other unforeseen events that cause...... road capacity to decrease. We refer to this uncertainty as travel time variability (TTV). TTV is likely to affect how travellers schedule their trips, since it affects their probability of arriving late at their destination. We would like to account for TTV in traffic models and cost-benefit analyses......, but in practice there are limits to the kinds of behaviour that can be accommodated in such applications. For that reason, we are not solely interested in explaining travellers’ behaviour, but also in whether this behaviour can be approximated by behavioural models that are simple enough to be applied in traffic...

  19. Vehicle Routing Problem with Backhaul, Multiple Trips and Time Window

    Directory of Open Access Journals (Sweden)

    Johan Oscar Ong

    2011-01-01

    Full Text Available Transportation planning is one of the important components to increase efficiency and effectiveness in the supply chain system. Good planning will give a saving in total cost of the supply chain. This paper develops the new VRP variants’, VRP with backhauls, multiple trips, and time window (VRPBMTTW along with its problem solving techniques by using Ant Colony Optimization (ACO and Sequential Insertion as initial solution algorithm. ACO is modified by adding the decoding process in order to determine the number of vehicles, total duration time, and range of duration time regardless of checking capacity constraint and time window. This algorithm is tested by using set of random data and verified as well as analyzed its parameter changing’s. The computational results for hypothetical data with 50% backhaul and mix time windows are reported.

  20. Microprocessor tester for the treat upgrade reactor trip system

    International Nuclear Information System (INIS)

    The upgrading of the Transient Reactor Test (TREAT) Facility at ANL-Idaho has been designed to provide additional experimental capabilities for the study of core disruptive accident (CDA) phenomena. In addition, a programmable Automated Reactor Control System (ARCS) will permit high-power transients up to 11,000 MW having a controlled reactor period of from 15 to 0.1 sec. These modifications to the core neutronics will improve simulation of LMFBR accident conditions. Finally, a sophisticated, multiply-redundant safety system, the Reactor Trip System (RTS), will provide safe operation for both steady state and transient production operating modes. To insure that this complex safety system is functioning properly, a Dedicated Microprocessor Tester (DMT) has been implemented to perform a thorough checkout of the RTS prior to all TREAT operations

  1. 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 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...... 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....

  2. Multiple Objects Tracking Using CAMShift Algorithm and Implementation of Trip Wire

    Directory of Open Access Journals (Sweden)

    Shirish Halbe

    2013-05-01

    Full Text Available In this paper we represent Security application which is developed using concepts of Video Analytics. User can draw Trip wire on video stream with help of Mouse Callback events. Using this application user can restrict any area of total video scene. Direction selection for tripping is also a choice of a user. If any undesired moving object cross this drawn trip wire then motion of this moving object is getting detected and also tracked. If object crosses trip wire in the same direction as that of user selected then Alarm Indication will appear on that moving object. OpenCV library functions are used for motion detection and motion tracking. CAMShift algorithm is implemented for tracking. An experimental result shows Motion detection, Motion Tracking and drawn trip wire on video.

  3. 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...

  4. Design, Fabrication and pseudo Field Evaluation of a Sugar Beet Crust Breaker and Weeding Unit Equipped with an Infrared Sensor

    Directory of Open Access Journals (Sweden)

    E Chaligar

    2014-09-01

    Full Text Available In conventional cultivation of sugar beet the weeding and crust breaking are mostly performed manually. The objectives of this research were to design, fabricate and evaluate a soil crust breaker and weeding implement equipped with a detecting sensor. Each unit consisted of a distance detecting sensor and a hydro-motor for driving the blades and pneumatic valves for moving the blades. The hydro-motor was activated by the sensors. To avoid damaging the plants, a command signal was sent to the pneumatic valves to move the blades up and down and pass safely. Three configurations of cutting blades were considered which could be mounted to the crust breaker. The field evaluation was conducted with two tractor forward speeds (0.4 and 1 km h-1 and four plant-to-plant spacings within rows (20, 25, 30 and 40 cm all with three different blade shapes. For field evaluation split plot experiments arranged in a completely randomized block design with three replications. The number of plants damaged (evaluated only for four-lobe blades and size of broken crusts (evaluated for all blade shapes for various treatments were recorded and compared. The results of analysis indicated that the higher the inter-row spacing the lower the injury to the plant. The highest and the least damage to the plants occurred for within-row plant spacings of 20 and 40 cm, respectively. The forward speed was also significantly affected the percent of plant damaged. The forward speed of 1 km h-1 at 20 cm spacing had the most (59% and the speed of 0.40 km h-1 at 40 cm spacing had the least effect (3.3% on the percent of plant damage. The two-lobe blade could result in the maximum surface area broken.

  5. Scaled photographs of surf over the full range of breaker sizes on the north shore of Oahu and Jaws, Maui, Hawaiian Islands, January 1998 - May 2004 (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...

  6. Georges Bank conflict resolved

    Science.gov (United States)

    Robb, David W.

    1984-04-01

    The International Court of Justice has resolved the long-term conflict between the United States and Canada over claims to mineral and living resources lying along the countries' common Atlantic maritime border. On October 12, in a 4-1 decision, the World Court rejected the United States' claim to the entire Georges Bank area, a region of the Continental Shelf off Massachusetts and Nova Scotia that is a prime fishing ground and is believed to have good potential for oil and gas deposits as well. The disputed area is roughly the top third of the Georges Bank area. The court awarded each country approximately half of this disputed area. No appeals are allowed under this decision.

  7. 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

  8. Cause analysis of circuit breaker tripping caused by AC power flowing into DC circuit%交流电源串入直流电源回路导致断路器跳合闸原因分析

    Institute of Scientific and Technical Information of China (English)

    赵永生; 庄洪波

    2010-01-01

    介绍2起多台断路器同时跳闸或合闸的典型事故,通过现场试验验证和分析,证明当交流电源串入直流电源回路中,可能引起多台断路器跳闸或合闸,并提出防范措施.

  9. The View at the Zoo: Using a Photographic Scavenger Hunt as the Basis for an Interdisciplinary Field Trip

    Science.gov (United States)

    Gilbert, Lynn; Breitbarth, Pamela; Brungardt, Matthew; Dorr, Carrie; Balgopal, Meena

    2010-01-01

    Most educators have a love-hate relationship with field trips. On the one hand, field trips are a great way to get students out of the building, enhance learning, and have some fun. On the other hand, field trips are a lot of work and worry. Especially now, with the increased cost of transportation and the need for curricular ties, field trips…

  10. Meta-Analytic Evaluation of a Virtual Field Trip to Connect Middle School Students with University Scientists

    Science.gov (United States)

    Adedokun, Omolola A.; Liu, Jia; Parker, Loran Carleton; Burgess, Wilella

    2015-01-01

    Although virtual field trips are becoming popular, there are few empirical studies of their impacts on student outcomes. This study reports on a meta-analytic evaluation of the impact of a virtual field trip on student perceptions of scientists. Specifically, the study examined the summary effect of zipTrips broadcasts on evaluation…

  11. Analysis on Connection Error in Current Transformer Secondary Circuit of 500 kV Tank Circuit Breaker with Countermeasures%500kV罐式断路器电流互感器二次回路接线错误的分析及对策

    Institute of Scientific and Technical Information of China (English)

    杨忠礼; 牛元泰; 吴征; 任平力

    2012-01-01

    介绍了一起因500 kV罐式断路器电流互感器二次回路接线错误而产生的重大隐患,当500 kV罐式断路器本体发生故障时,由于线路保护与母线保护使用的电流互感器绕组接线未实现交叉,使得两者的保护范围没有交叉,存在保护死区,从而会导致主保护拒动.通过对全站500 kV系统保护用电流互感器绕组接线的检查和分析,发现造成保护死区主要是设计和安装两方面的原因,针对这两方面原因,提出了加强规范管理,在设计施工阶段加强一二次施工人员的配合以及施工、验收和日常维护时注重对该部分的检查等一系列具体的反事故措施,为今后罐式断路器继电保护用电流互感器绕组的设计、安装调试以及现场验收及维护提供了借鉴.%A hidden danger owing to connection error in the current transformer secondary circuit of 500 kV tank circuit breaker is introduced. When the 500 kV tank circuit breaker went wrong, the main protections did not trip to clear the fault because current transformer windings for respective line protection and bus protection had not been cross-connected hence two protection ranges did not overlapped and main protection did not work. The protection dead zone is found to be due to some problems in both design and installation of the current transformer through checking and analyzing the current transformer winding. Consequently, some countermeasures' for avoiding the protection dead zone are suggested, such as strengthening cooperation between primary and secondary builders during design and installation stage, and paying more attention to examinations in construction, acceptance and daily maintenance stages.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wurong; Guo Bimeng; Ji Yurong; He Changwei [School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Wei Xicheng, E-mail: wxc1028@staff.shu.edu.cn [School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China)

    2012-06-01

    Highlights: Black-Right-Pointing-Pointer The tensile mechanical behaviors of TRIP steels were studied under high rate deformation conditions. Black-Right-Pointing-Pointer The threshold strain of microvoid formation was examined quantitatively. Black-Right-Pointing-Pointer 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. Biaxial fatigue behavior of a powder metallurgical TRIP steel

    Directory of Open Access Journals (Sweden)

    S. Ackermann

    2015-10-01

    Full Text Available Multiaxial fatigue behavior is an important topic in critical structural components. In the present study the biaxial-planar fatigue behavior of a powder metallurgical TRIP steel (Transformation Induced Plasticity was studied by taking into account martensitic phase transformation and crack growth behavior. Biaxial cyclic deformation tests were carried out on a servo hydraulic biaxial tension-compression test rig using cruciform specimens. Different states of strain were studied by varying the strain ratio between the axial strain amplitudes in the range of -1 (shear loading to 1 (equibiaxial loading. The investigated loading conditions were proportional due to fixed directions of principal strains. The studied TRIP steel exhibits martensitic phase transformation from -austenite via ε-martensite into α‘- martensite which causes pronounced cyclic hardening. The α‘-martensite formation increased with increasing plastic strain amplitude. Shear loading promoted martensite formation and caused the highest α‘-martensite volume fractions at fatigue failure in comparison to uniaxial and other biaxial states of strain. Moreover, the fatigue lives of shear tests were higher than those of uniaxial and other biaxial tests. The von Mises equivalent strain hypothesis was found to be appropriate for uniaxial and biaxial fatigue, but too conservative for shear fatigue, according to literature for torsional fatigue. The COD strain amplitude which is based on crack opening displacement gave a better correlation of the investigated fatigue lives, especially those for shear loading. Different types of major cracks were observed on the sample surfaces after biaxial cyclic deformation by using electron monitoring in an electron beam universal system and scanning electron microscopy (SEM. Specimens with strain ratios of 1, 0.5, -0.1 and -0.5 showed mode I major cracks (perpendicular to the axis of maximum principal strain. Major cracks after shear fatigue

  14. TAN/LOFT 13. 8 KV, 2. 4 KV, and 480 V relay and circuit breaker coordination study

    Energy Technology Data Exchange (ETDEWEB)

    Burnett, J.E.

    1977-10-28

    Present overcurrent relay settings are presented and evaluated for adequacy in terms of the updated short circuit analysis. Recommendations are made for new relay and trip device settings to improve coordination. Switchgear ratings are examined against available short circuit currents, and recommendations are made where applicable. Vital MCC-A and B are examined in detail to provide maximum continuity of service for every fault contingency. A recommendation is made to improve the reliability of these buses.

  15. Mechanical properties and microstructure of TRIP steels produced using TSCR process

    Institute of Scientific and Technical Information of China (English)

    Yinghui Zhang; Yanli Ma; Yonglin Kang; Hao Yu

    2006-01-01

    C-Si-Mn TRIP steels were produced using the thin slab casting and rolling (TSCR) process under simulation in laboratory. The results of tensile tests show that the yield strength, tensile strength, and the total elongation of the experimental TRIP steels are 430 MPa, 610 MPa, and 28.4%, respectively. Optical microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were employed to identify the microstructures of the TRIP steels. The final microstructures consist of ferrite, bainite, and retained austenite. The results of quantitative color metallography show that the fraction of the retained austenite is about 5.8%.

  16. Analysis of a single primary coolant pump trip scenario in a PHWR

    International Nuclear Information System (INIS)

    This paper addresses the analysis of a single primary coolant pump (PCP) trip scenario in a 220 MWe Indian pressurized heavy water reactor (PHWR). The analysis is carried out using a lumped parameter model. The time dependent mass, momentum and energy for conservation equations for the primary system are solved using finite difference scheme. The predictions of the model for the time required to reach the over-pressure trip value was in good agreement with the plant data. Parametric studies are carried out to study the influences of the isolation of the failed branch and a delay in the trip of the diagonally opposite PCP. (author). 2 refs., 13 figs., 1 tab

  17. Research on Public Transit Network Hierarchy Based on Residential Transit Trip Distance

    Directory of Open Access Journals (Sweden)

    Gao Jian

    2012-01-01

    Full Text Available To the problem of being lack of transit network hierarchy theory, a research on public transit network hierarchy optimization based on residential transit trip distance is conducted. Firstly, the hierarchy standard of transit network is given, in addition, both simulating electron cloud model and Rayleigh distribution model are used to fit the residential transit trip distance. Secondly, from the view of balance between supply and demand, the hierarchy step of transit network based on residential transit trip distance is proposed. Then, models of transit’s supply turnover and demand turnover are developed. Finally, the method and models are applied into transit network optimization of Baoding, Hebei, China.

  18. Studying Geology of Central Texas through Web-Based Virtual Field Trips

    Science.gov (United States)

    Chan, C.; Khan, S. D.; Wellner, J. S.

    2007-12-01

    Each year over 2500 students, mainly non-science majors, take introductory geology classes at the University of Houston. Optional field trips to Central Texas for these classes provide a unique learning opportunity for students to experience geologic concepts in a real world context. The field trips visit Enchanted Rock, Inks Lake, Bee Cave Road, Lion Mountain, and Slaughter Gap. Unfortunately, only around 10% of our students participate in these field trips. We are developing a web-based virtual field trip for Central Texas to provide an additional effective learning experience for students in these classes. The module for Enchanted Rock is complete and consists of linked geological maps, satellite imagery, digital elevation models, 3-D photography, digital video, and 3-D virtual reality visualizations. The ten virtual stops focus on different geologic process and are accompanied by questions and answers. To test the efficacy of the virtual field trip, we developed a quiz to measure student learning and a survey to evaluate the website. The quiz consists of 10 questions paralleling each stop and information on student attendance on the Central Texas field trip and/or the virtual field trip. From the survey, the average time spent on the website was 26 minutes, and overall the ratings of the virtual field trip were positive. Most noticeably students responded that the information on the website was relevant to their class and that the pictures, figures, and animations were essential to the website. Although high correlation coefficients between responses were expected for some questions (i.e., 0.89 for "The content or text of the website was clear" and "The information on the website was easy to read"), some correlations were less expected: 0.77 for "The number of test questions was appropriate" and "The information on the website was easy to read," and 0.70 for "The test questions reinforced the material presented on the website" and "The information on the

  19. Thermal Stability of Retained Austenite in TRIP Steel After Different Treatments

    Institute of Scientific and Technical Information of China (English)

    SHI Wen; LI Lin; Bruno C De Cooman; Patrick Wollants; YANG Chun-xia

    2008-01-01

    Thermal decomposition of retained austenite in TRIP steel was investigated by means of differential scanning calorimetry (DSC). The decomposition curve was abnormal, and the decomposition temperature and the activation energy were measured by the Kissinger method, which were all higher than those in quenched steel. The thermal decomposition data of samples soaked in liquid nitrogen after TRIP treatment were all similar to those without additional low temperature treatment. It indicated that there is a high thermal stability in retained austenite of the TRIP steel at low temperature, which was also proved by XRD analysis.

  20. 带电测量断路器接触电阻方法的研究%Design of Electriifed Measuring Contact Resistance in Circuit Breakers

    Institute of Scientific and Technical Information of China (English)

    陈杏灿; 程汉湘; 彭湃; 冼冀

    2015-01-01

    This paper presented a new real-time measuring method for the contact resistance of the operated circuit breakers. A pair of potential transformer worked in parallel to measure indirectly the voltage difference on the two terminals of the circuit breaker, while the currents lfowing through circuit breakers were measured by current transformers. The result of contact resistance could be obtained based on Ohm Law. The analysis shows that this method could not only guarantee the isolation between control system and strong current, but also measure the contact resistance in real time, which would effectively prevent circuit breakers accidents.%提出了一种可对运行中的断路器实时测量其接触电阻的新方法。通过两个电压互感器采集断路器两端对地电压,求得断路器两端的电压差,同时测得流过断路器的电流,根据欧姆定律即可得接触电阻。分析表明,该方法可在保证测量系统与高压隔离的前提下,实时带电测量断路器的接触电阻。对预防断路器的安全事故,保证断路器可靠运行具有重要意义。

  1. TRIP: a novel double stranded RNA binding protein which interacts with the leucine rich repeat of flightless I.

    OpenAIRE

    Wilson, S A; Brown, E C; Kingsman, A J; Kingsman, S M

    1998-01-01

    A northwestern screen of a CHO-K1 cell line cDNA library with radiolabelled HIV-1 TAR RNA identified a novel TAR RNA interacting protein, TRIP. The human trip cDNA was also cloned and its expression is induced by phorbol esters. The N-terminus of TRIP shows high homology to the coiled coil domain of FLAP, a protein which binds the leucine-rich repeat (LRR) of Flightless I (FLI) and the interaction of TRIP with the FLI LRR has been confirmed in vitro . TRIP does not bind single stranded DNA or...

  2. Application of Fast Vacuum Circuit Breaker in Electric System%快速真空断路器在电力系统中的应用

    Institute of Scientific and Technical Information of China (English)

    艾绍贵; 马奎; 吴旭涛; 孙丽琼

    2016-01-01

    介绍了涡流驱动型快速真空断路器的原理,分析了目前配网消弧消谐、故障选线及触电防护、电网短路电流限制、串联补偿及变压器直流偏磁抑制等技术的现状和存在的问题。根据快速真空断路器特点,提出了解决相关技术问题的方法,阐述了相关装置的结构、试验及应用情况,并对快速真空断路器在电力系统中的应用进行了展望。%Introduction was made to the principle of eddy current forced fast vacuum circuit breaker. Analysis was made to the technolo-gies used and problems existing including arc and resonance elimination, fault line selection and electric shock protection, grid short-circuit current limitation, series compensation and transformer direct current magnetic bias suppression etc technologies in distribution network at present. According to the characteristic of fast vacuum circuit breaker, the solution method of those problems was proposed. This paper ex-pounded the structure, experiment and application of the relevant device. The further application of the circuit breaker is prospected.

  3. 大容量发电机出口断路器选择%Circuit Breakers Selection Method for Large-capacity AC High-voltage Generator

    Institute of Scientific and Technical Information of China (English)

    张爽

    2011-01-01

    针对大容量发电机出口断路器的选择问题,依据GB/T 14824-2008、IEEE Std C37.013-1997和IEC 60909-0-2001中的计算方法,并结合发电机出口断路器型式试验报告的有关数据,以某百万千瓦级发电机组为例进行了比较计算,分析计算结果,提出了对发电机出口短路器短路电流开断能力不能采用百分比而应采用绝对值进行校验.%For selecting large-capacity AC high-voltage generator circuit breakers in a large generator system, comparative calculations are conducted for a million kilowatts rated generator following the standards of GB/T 14824-2008, IEEE Std C37.013-1997 and IEC 60909-0-2001. The calculation results and the test reports of generator circuit breakers are analyzed, and a suggestion is hence offered that absolute value of short-circuit current should be used for examining the short-circuit current breaking capacity of an AC high-voltage generator circuit breaker instead of percentage value.

  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. Trip report: a visit to the Swedish reindeer industry, 1986

    International Nuclear Information System (INIS)

    The State of Alaska indicated recently that it will become more strict in enforcing inspection requirements for reindeer meat that is mixed with meat from domestic animals (e.g., In sausage production). Therefore. we wanted to observe how reindeer are slaughtered to meet Swedish meat inspection requirements. Additionally, by following the processing and marketing of reindeer in Sweden, we hoped to discover alternative products that do not require blending reindeer with beef or pork. The Chernobyl tragedy further affected our decision to visit Sweden in two ways It gave us the opportunity to review the Impacts of widespread, Intense radioactive contamination on reindeer and the reindeer industry: and it created a shortage or reindeer for human consumption in Sweden which In turn appeared to open a market for Alaska reindeer products. Between 13 and 23 November 1986, we traveled to Sweden to meet suppliers and processors in the Swedish reindeer (Rangifer tarandus tarandus) industry. Wholesale and retail marketing of reindeer were reviewed in Stockholm; corralling, slaughter, and processing of reindeer were observed in Swedish Lapland. The specific objectives of this trip were as follows: 1) to observe reindeer slaughter facilities and techniques used in Sweden; 2) to trace the marketing of reindeer from Sami herders to retail outlets; 3) to assess radioactive contamination of reindeer and their ranges and observe how the problem is being handled; 4) to observe as many reindeer husbandry techniques as possible; and 5) to explore the possibility of establishing a market for Alaskan reindeer meat in Sweden

  6. The issue of accelerator beam trips for efficient ADS operation

    International Nuclear Information System (INIS)

    The development of accelerator-driven systems (ADSs) is motivated by the potential of these machines to reduce the volume and the radiotoxicity of accumulated nuclear waste, more particularly that of minor actinides currently generated by the operation of existing pressurized water reactors. The reduction of both volume and radiotoxicity of nuclear waste is achieved by transmutation and fission of minor actinides into less-active isotopes or shorter-lived by-products. Various technical challenges exist regarding designing reliable and efficient ADSs. The key points are very much linked to the design of the spallation module, the assurance that reactivity remains below criticality under any circumstances, and the accelerator reliability. This paper addresses the latter two challenges imposed on the accelerator in order to assure safe and reliable ADS operation. It discusses the possibility of performing online absolute reactivity measurements and the limits in the number of allowable accelerator beam trips, which might impede plant integrity and/or plant efficiency. (authors)

  7. Collective human mobility pattern from taxi trips in urban area

    KAUST Repository

    Peng, Chengbin

    2012-04-18

    We analyze the passengers\\' traffic pattern for 1.58 million taxi trips of Shanghai, China. By employing the non-negative matrix factorization and optimization methods, we find that, people travel on workdays mainly for three purposes: commuting between home and workplace, traveling from workplace to workplace, and others such as leisure activities. Therefore, traffic flow in one area or between any pair of locations can be approximated by a linear combination of three basis flows, corresponding to the three purposes respectively. We name the coefficients in the linear combination as traffic powers, each of which indicates the strength of each basis flow. The traffic powers on different days are typically different even for the same location, due to the uncertainty of the human motion. Therefore, we provide a probability distribution function for the relative deviation of the traffic power. This distribution function is in terms of a series of functions for normalized binomial distributions. It can be well explained by statistical theories and is verified by empirical data. These findings are applicable in predicting the road traffic, tracing the traffic pattern and diagnosing the traffic related abnormal events. These results can also be used to infer land uses of urban area quite parsimoniously. 2012 Peng et al.

  8. Meaningful Field Trip in Education of Renewable Energy Technologies

    Directory of Open Access Journals (Sweden)

    Hasan Said Tortop

    2013-06-01

    Full Text Available Renewable energy sources, in terms of countries‟ obtaining their energy needs from clean and without harming the environment is becoming increasingly important. This situation also requires improving the quality of science education will be given in this field. In this activity, in a field trip to the center for the renewable energy resources technologies, the application of learning cycle model appropriate for constructivist approach is shown. In the example of solar chimney activity according to 5E model, in elaboration step, students, by using their imagination and creativity, put out recommendations and new designs for the efficiency of the application of solar chimney. It is quite important for educators to follow what kind of acquisitions that students will gain and what kind of changes will occur in their perceptions and attitudes towards renewable energy technologies thanks to this activity. Related documents are in attachments. This activity has been very helpful in the education of young scientists on the field of renewable energy sources technologies.

  9. Collective human mobility pattern from taxi trips in urban area.

    Directory of Open Access Journals (Sweden)

    Chengbin Peng

    Full Text Available We analyze the passengers' traffic pattern for 1.58 million taxi trips of Shanghai, China. By employing the non-negative matrix factorization and optimization methods, we find that, people travel on workdays mainly for three purposes: commuting between home and workplace, traveling from workplace to workplace, and others such as leisure activities. Therefore, traffic flow in one area or between any pair of locations can be approximated by a linear combination of three basis flows, corresponding to the three purposes respectively. We name the coefficients in the linear combination as traffic powers, each of which indicates the strength of each basis flow. The traffic powers on different days are typically different even for the same location, due to the uncertainty of the human motion. Therefore, we provide a probability distribution function for the relative deviation of the traffic power. This distribution function is in terms of a series of functions for normalized binomial distributions. It can be well explained by statistical theories and is verified by empirical data. These findings are applicable in predicting the road traffic, tracing the traffic pattern and diagnosing the traffic related abnormal events. These results can also be used to infer land uses of urban area quite parsimoniously.

  10. Field trip guide to selected outcrops, Arbuckle Mountains, Oklahoma

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-11-17

    The Arbuckle Mountains, named for Brigadier General Matthew Arbuckle, are located in south-central Oklahoma. The formations that comprise the Arbuckle Mountains have been extensively studied for hydrocarbon source rock and reservoir rock characteristics that can be applied to the subsurface in the adjacent Anadarko and Ardmore basins. Numerous reports and guidebooks have been written concerning the Arbuckle Mountains. A few important general publications are provided in the list of selected references. The purpose of this handout is to provide general information on the geology of the Arbuckle Mountains and specific information on the four field trip stops, adapted from the literature. The four stops were at: (1) Sooner Rock and Sand Quarry; (2) Woodford Shale; (3) Hunton Anticline and Hunton Quarry; and (4) Tar Sands of Sulfur Area. As part of this report, two papers are included for more detail: Paleomagnetic dating of basinal fluid migration, base-metal mineralization, and hydrocarbon maturation in the Arbuckle Mountains, Oklahoma and Laminated black shale-bedded chert cyclicity in the Woodford Formation, southern Oklahoma.

  11. Skip the trip: air travelers' behavioral responses to pandemic influenza.

    Directory of Open Access Journals (Sweden)

    Eli P Fenichel

    Full Text Available Theory suggests that human behavior has implications for disease spread. We examine the hypothesis that individuals engage in voluntary defensive behavior during an epidemic. We estimate the number of passengers missing previously purchased flights as a function of concern for swine flu or A/H1N1 influenza using 1.7 million detailed flight records, Google Trends, and the World Health Organization's FluNet data. We estimate that concern over "swine flu," as measured by Google Trends, accounted for 0.34% of missed flights during the epidemic. The Google Trends data correlates strongly with media attention, but poorly (at times negatively with reported cases in FluNet. Passengers show no response to reported cases. Passengers skipping their purchased trips forwent at least $50 M in travel related benefits. Responding to actual cases would have cut this estimate in half. Thus, people appear to respond to an epidemic by voluntarily engaging in self-protection behavior, but this behavior may not be responsive to objective measures of risk. Clearer risk communication could substantially reduce epidemic costs. People undertaking costly risk reduction behavior, for example, forgoing nonrefundable flights, suggests they may also make less costly behavior adjustments to avoid infection. Accounting for defensive behaviors may be important for forecasting epidemics, but linking behavior with epidemics likely requires consideration of risk communication.

  12. Time-resolved studies

    International Nuclear Information System (INIS)

    When new or more powerful probes become available that offer both shorter data-collection times and the opportunity to apply innovative approaches to established techniques, it is natural that investigators consider the feasibility of exploring the kinetics of time-evolving systems. This stimulating area of research not only can lead to insights into the metastable or excited states that a system may populate on its way to a ground state, but can also lead to a better understanding of that final state. Synchrotron radiation, with its unique properties, offers just such a tool to extend X-ray measurements from the static to the time-resolved regime. The most straight-forward application of synchrotron radiation to the study of transient phenomena is directly through the possibility of decreased data-collection times via the enormous increase in flux over that of a laboratory X-ray system. Even further increases in intensity can be obtained through the use of novel X-ray optical devices. Widebandpass monochromators, e.g., that utilize the continuous spectral distribution of synchrotron radiation, can increase flux on the sample several orders of magnitude over conventional X-ray optical systems thereby allowing a further shortening of the data-collection time. Another approach that uses the continuous spectral nature of synchrotron radiation to decrease data-collection times is the open-quote parallel data collectionclose quotes method. Using this technique, intensities as a function of X-ray energy are recorded simultaneously for all energies rather than sequentially recording data at each energy, allowing for a dramatic decrease in the data-collection time

  13. Trip Length Distribution Under Multiplicative Spatial Models of Supply and Demand: Theory and Sensitivity Analysis

    CERN Document Server

    Veneziano, Daniele

    2011-01-01

    We propose new probabilistic models for the spatial distribution of supply and demand and use the models to determine how the trip length distribution is affected by the relative shortage or excess of supply, the spatial clustering of supply and demand, and the degree of attraction or repulsion between supply and demand at different spatial scales. The models have a multiplicative structure and in certain cases possess scale invariance properties. Using detailed population data in metropolitan US regions validates the demand model. The trip length distribution, evaluated under destination choice models of the intervening opportunities type, has quasi-analytic form.We take advantage of this feature to study the sensitivity of the trip length distribution to parameters of the demand, supply and destination choice models. We find that trip length is affected in important but different ways by the spatial density of potential destinations, the dependence among their attractiveness levels, and the correlation betw...

  14. A system for trip analysis of PWR reactors using neural networks

    International Nuclear Information System (INIS)

    This work presents the basic concepts and the general description of a computational system developed for trip analysis in PWR nuclear power plants which is based on neural networks and artificial intelligence concepts. (author)

  15. 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.

  16. 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.

  17. A Way to Change Learning: Field Trips as a University Pedagogical Resource

    Directory of Open Access Journals (Sweden)

    Érika Vásquez Salazar

    2014-01-01

    Full Text Available This article represents the systematization of different experiences related to educational field trips in higher education taking place between 2005 and 2012 within the Primary Education Division (DEB at Universidad Nacional, Costa Rica. Field trips were used as an educational resource to develop attitudes and aptitudes in students from various education majors. The author proposes pedagogical field trips as a possible strategy to promote innovation in higher education and achieve a positive change in teaching and learning processes. Field trips are presented as a tool that allows students to complete their coursework in a more significant and participative manner being in contact with the educational reality and to become humanized and to reinvent themselves as persons and future teachers.

  18. 49 CFR 236.560 - Contact element, mechanical trip type; location with respect to rail.

    Science.gov (United States)

    2010-10-01

    ... SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Locomotives § 236.560 Contact element, mechanical trip type; location with respect to...

  19. Field trip guide to the Valles Caldera and its geothermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.E.; Bolivar, S.L.

    1983-12-01

    This field trip guide has been compiled from extensive field trips led at Los Alamos National Laboratory during the past six years. The original version of this guide was designed to augment a workshop on the Valles Caldera for the Continental Scientific Drilling Program (CSDP). This workshop was held at Los Alamos, New Mexico, 5-7 October 1982. More stops were added to this guide to display the volcanic and geothermal features at the Valles Caldera. The trip covers about 90 miles (one way) and takes two days to complete; however, those who wish to compress the trip into one day are advised to use the designated stops listed in the Introduction. Valles Caldera and vicinity comprise both one of the most exciting geothermal areas in the United States and one of the best preserved Quaternary caldera complexes in the world.

  20. Mechanical and Transformation Behaviors of a C-Mn-Si-Al-Cr TRIP Steel under Stress

    Institute of Scientific and Technical Information of China (English)

    Xiaodong WANG; Baoxu HUANG; Yonghua RONG; Li WANG

    2006-01-01

    Transformation induced plasticity(TRIP)steels combine high strength and excellent ductility, making them suited for application in crash-relevant parts in the automotive industry. However, the high Si contents in the conventional TRIP steel will generate surface defects on the hot rolled strip, which is difficult to process in continuous galvanizing lines. In order to solve the above problem the TRIP steel with the addition of Al replacing majority of Si was designed. In the present paper, the volume fraction of various phases in a C-Mn-Si-Al-Cr TRIP steel was determined by metallographic examination and X-ray diffraction analysis, and the multi-phase microstructures were characterized using an atomic force microscope based on their height difference. Tensile tests were performed at differenttemperatures ranging from -40℃ to 90℃. The results show that transition temperature Mσs in the present TRIP steel cannot be determined due to its lower volume fraction of retained austenite, different from the conventional TRIP steel. While the yield stress and tensile strength at different temperatures are higher than those of the conventional TRIP steel, which is attributed to the addition of Cr. In order to evaluate the effect of martensitic transformation on the total elongation, the sample without retained austenite obtainedby quenching in liquid nitrogen was carried out under tensile test.The results indicate that the elongation of the original sample containing 9% retained austenite is about 20%higher than that of the sample quenched in liquid nitrogen, which demonstrates that the retained austenite plays an important role in improving the elongation of the TRIP steel.

  1. Patterns of energy acquisition by penguins: benefits of alternating short and long foraging trips.

    OpenAIRE

    Ropert-Coudert, Y.; Wilson, Rory P.; Daunt, F; Kato, A

    2004-01-01

    In some seabirds, foraging trips have been defined as either long or short, with the length of time spent traveling to the foraging area apparently a critical feature in determining foraging trip length. Using logger technology, together with complimentary data from published studies, we investigated traveling and foraging times in 18 free-living Adélie Penguins Pygoscelis adeliae, which were foraging for chicks. Most deep, foraging dives were distributed around the center of the foraging tri...

  2. Does Ignoring Multi-Destination Trips in the Travel Cost Method Cause a Systematic Downward Bias?

    OpenAIRE

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

    2003-01-01

    In theory, treating the multi-destination trips (MDTs) as single-destination trips (SDT) does not necessarily lead to biased results, because negative effect of price increase may be offset by the shift of the estimated demand curve. However, in our empirical application of the TCM zonal model to the valuation of the economic benefits of the Bellenden Kerr National Park in Australia we find (statistically significant) evidence that ignoring the MDTs leads to a dramatic overestimation of the c...

  3. Non-Work Activity Scheduling Effects in the Timing of Work Trips

    OpenAIRE

    Picado, Rosella

    1999-01-01

    This dissertation examines the effect of work and non-work scheduling flexibility on the timing of work trips. It explores whether increasing activity scheduling flexibility, whether due to work or non-work factors, results in non-peak travel and hence shorter travel times. It examines in detail work scheduling flexibility, non-work scheduling flexibility, and travel time characteristics. An examination of trip timing choices using data from the 1990 Bay Area Travel Survey showed tha...

  4. Identifying future research opportunities in online consumer reviews : the case study of TripAdvisor

    OpenAIRE

    Whitehead, Lisa

    2011-01-01

    The aim of this article is to identify future research opportunities for using online consumer reviews websites such as TripAdvisor.com as a case study. The literature review covers the internet and growth of eTourism, virtual communities, virtual community typologies, and the importance of TripAdvisor.com for travel research, electronic word–of–mouth (eWOM), social networking and the impact of online travel reviews on consumers. Propositions and future research opportunities are then raised....

  5. Phasenumwandlung und lokale mechanische Eigenschaften von TRIP Stahl beim simulierten und realen Widerstandspunktschweißprozess

    OpenAIRE

    Brauser, Stephan

    2012-01-01

    TRIP Stähle realisieren durch eine unter mechanischer Beanspruchung hervorgerufene Pha-senumwandlung von metastabilen Austenit in Martensit (TRIP-Effekt) hohe Festigkeiten bei gleichzeitig guten Verformungseigenschaften. Während der Verarbeitung dieser Werkstoffe mittels Widerstandspunktschweißen können unter den prozessspezifischen extremen Aufheiz- und Abkühlraten Modifikationen des Austenitanteils hervorgerufen werden die als Folge lokal zu einer Änderung der mechanisch-technologischen Eig...

  6. AB TEMPORAL TRIP GENERATION MODELLING FOR PRIMARY ACTIVITIES: A CASE STUDY OF FAST GROWING METROPOLITAN CITY

    Directory of Open Access Journals (Sweden)

    Bhimaji K. Katti

    2015-06-01

    Full Text Available Transportation planning for any city evolves on the basis of complex interplay between urban activity, transport and land use system to result in varied travel patterns. Travel pattern can be defined at micro level to include individual journey departure and arrival time, journey duration and distances to make way for temporal trip generation and distribution from specific area. Trip generation is the first step of four stages of travel forecasting analysis mostly followed all over the world. Traditionally, it is focused on the prediction of aggregate trip generation by a household rather than the choice of individual activity participation. However, spatial and temporal activity domains are equally important in forecasting process and strategic urban transportation planning. The present paper attempts to develop Activity Based (AB Temporal Trip Generation Models (ABTGM for primary activities to cover work and educational trips considering fast growing Surat city of Gujarat, India as study area. Home interview surveys are carried to provide household and socioeconomic characteristics and the activity travel diary information to focus on the activity based tours rather the trips.

  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. Round-Trip Voronoi Diagrams and Doubling Density in Geographic Networks

    CERN Document Server

    Dickerson, Matthew T; Dickerson, Thomas D

    2010-01-01

    The round-trip distance function on a geographic network (such as a road network, flight network, or utility distribution grid) defines the "distance" from a single vertex to a pair of vertices as the minimum length tour visiting all three vertices and ending at the starting vertex. Given a geographic network and a subset of its vertices called "sites" (for example a road network with a list of grocery stores), a two-site round-trip Voronoi diagram labels each vertex in the network with the pair of sites that minimizes the round-trip distance from that vertex. Alternatively, given a geographic network and two sets of sites of different types (for example grocery stores and coffee shops), a two-color round-trip Voronoi diagram labels each vertex with the pair of sites of different types minimizing the round-trip distance. In this paper, we prove several new properties of two-site and two-color round-trip Voronoi diagrams in a geographic network, including a relationship between the "doubling density" of sites ...

  9. An implicit algorithm to verify creep and TRIP behavior of steel using uniaxial experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, Michael; Boehm, Michael; Boekenheide, Simone; Lammers, Daniel; Linke, Tobias [Bremen Univ. (Germany). Zentrum fuer Technomathematik

    2012-05-15

    Creep is a complex material feature occurring in mechanical structures under moderate stresses and relatively high temperatures. Transformation-induced plasticity (TRIP) is a macroscopic phenomenon of steel behavior. If phase transformations occur under deviatoric stress, a permanent inelastic strain is obtained even if the yield stress is not reached. Thus, creep and TRIP do not have a yield stress like plasticity and visco-plasticity. Sometimes, during heat treatment of steel, creep and TRIP appear together. In order to determine creep or TRIP behavior it is necessary to verify concrete material laws and to determine corresponding material parameters. For this reason, often uniaxial experiments with small probes are performed in special devices. It is the main purpose of this study, to develop a procedure for the verification of possible laws for creep and TRIP and for determining material parameters, using experimental data. Therefore, an implicit algorithm in two variants will be developed: strain-driven and stress-driven. These algorithms can also be applied to simulations of (spatially homogenous) uniaxial experiments. Based on these algorithms, an optimization scheme will be developed for finding material parameters which realize a best approximation. Finally, the developed procedure will be applied for the investigation of creep and TRIP during heating of the bearing steel 100Cr6 (SAE 52100). (orig.)

  10. Simulation of the Arc Behavior in Puffer-type High Voltage Circuit Breaker Considering the Influence of Nozzle Ablation

    Institute of Scientific and Technical Information of China (English)

    JIANG Xu; ZHONG Jianying; ZHANG Youpeng; ZHANG Gaochao; LI Xingwen; JIA Shenli

    2013-01-01

    In order to investigate the influence of nozzle ablation to arc,a 2 D axisymmetric magneto-hydro-dynamics arc model is developed to simulate the arc behavior during the whole interruption process in a puffer type high voltage circuit breaker,considering the nozzle ablating and the mixing process of Polytetrafluoroethylene(PTFE) vapor with SF6.The results show that the arc radius firstly increases and then decreases as arc current varies according to its sinusoida waveform.At 3.5 ms after arc initiation the nozzle ablation starts,and 2.5 ms later the current nearly reaches its peak value and nozzle ablation develops intensely.Meanwhile the nozzle is blocked by arc at this time and consequently the vapor concentration in nozzle reaches the highest.Then while the current decreasing and open distance increaseing the vapor concentration gradually decreases.Before current zero the extinction peak of arc voltage occurs.It indicates that the PTFE vapor enhances pressure rise in arc quenching chamber and strengthens the arc blocking effect on nozzle; the arc radius is wider and arc temperature is lower when nozzle ablation is considered.

  11. Field Experiments on 10 kV Switching Shunt Capacitor Banks Using Ordinary and Phase-Controlled Vacuum Circuit Breakers

    Directory of Open Access Journals (Sweden)

    Wenxia Sima

    2016-01-01

    Full Text Available During the switching on/off of shunt capacitor banks in substations, vacuum circuit breakers (VCBs are required to switch off or to switch on the capacitive current. Therefore, the VCBs have to be operated under a harsh condition to ensure the reliability of the equipment. This study presents a complete comparison study of ordinary and phase-controlled VCBs on switching 10 kV shunt capacitor banks. An analytical analysis for switching 10 kV shunt capacitor banks is presented on the basis of a reduced circuit with an ungrounded neutral. A phase selection strategy for VCBs to switch 10 kV shunt capacitor banks is proposed. Switching on current waveforms and switching off overvoltage waveforms with, and without, phase selection were measured and discussed by field experiments in a 110 kV substation in Chongqing, China. Results show that the operation of phase-controlled VCBs for 10 kV switching shunt capacitor banks is stable, and phase-controlled VCBs can be used to implement the 10 kV switching on/off shunt capacitor banks to limit the transient overvoltage and overcurrent. The values of overvoltage and inrush current using phase-controlled VCBs are all below those with ordinary VCBs.

  12. United States: Ukraine Technical Exchange II trip report

    International Nuclear Information System (INIS)

    May 15--21, 1994, the first technical conference was held at Hanford between Ukraine-Chornobyl, Westinghouse Hanford, and SAIC, to exchange technical information and experience gained in cleanup and stabilization of radioactive contamination at Hanford and Chornobyl. Protocol was signed for a second exchange and technology demonstration program in Kiev and near Chornobyl power plants. Technical Exchange No. 2 was held from August 28--September 9, 1994, with 3 focus areas: field demonstration of DOE-Hanford technologies and application to cleanup of contaminated lands resulting from 1986 Chornobyl accident; application of other US DOE-technologies; and observation/evaluation of Ukraine-developed technologies for potential application in USA. Three radiological mapping systems were demonstrated near Chornobyl: man-carried Ultrasonic Ranging and Data System, a mobile radiological data system, and NOMAD field gamma spectroscopy system. The Ukraine-Chornobyl team hosted technical presentations, discussions and field trips for 4.5 days, providing insight on the Chornobyl problem and allowing the US team to present overviews on DOE technologies that may be applicable to the Chornobyl situation. It is concluded that Ukrainian scientists have tremendous talent and expended considerable energy in attempting to tackle such a problem, but economic and cultural conditions with Ukraine have prevented them from acquiring the resources to implement basic aspects of characterization and remediation activities. Most of their publications are in Russian only. Their translation, plus resources to carry out proposals for bench scale and field demonstration projects, could benefit the DOE complex and other nuclear programs. The considerable cultural and economic change occurring in Ukraine, is providing opportunities for private industries to assist in the changes and for DOE, others to apply cleanup technologies, and it is essential that close institutional relations be established

  13. United States: Ukraine Technical Exchange II trip report

    Energy Technology Data Exchange (ETDEWEB)

    Moak, D.J.; Wendling, M.A.

    1995-02-01

    May 15--21, 1994, the first technical conference was held at Hanford between Ukraine-Chornobyl, Westinghouse Hanford, and SAIC, to exchange technical information and experience gained in cleanup and stabilization of radioactive contamination at Hanford and Chornobyl. Protocol was signed for a second exchange and technology demonstration program in Kiev and near Chornobyl power plants. Technical Exchange No. 2 was held from August 28--September 9, 1994, with 3 focus areas: field demonstration of DOE-Hanford technologies and application to cleanup of contaminated lands resulting from 1986 Chornobyl accident; application of other US DOE-technologies; and observation/evaluation of Ukraine-developed technologies for potential application in USA. Three radiological mapping systems were demonstrated near Chornobyl: man-carried Ultrasonic Ranging and Data System, a mobile radiological data system, and NOMAD field gamma spectroscopy system. The Ukraine-Chornobyl team hosted technical presentations, discussions and field trips for 4.5 days, providing insight on the Chornobyl problem and allowing the US team to present overviews on DOE technologies that may be applicable to the Chornobyl situation. It is concluded that Ukrainian scientists have tremendous talent and expended considerable energy in attempting to tackle such a problem, but economic and cultural conditions with Ukraine have prevented them from acquiring the resources to implement basic aspects of characterization and remediation activities. Most of their publications are in Russian only. Their translation, plus resources to carry out proposals for bench scale and field demonstration projects, could benefit the DOE complex and other nuclear programs. The considerable cultural and economic change occurring in Ukraine, is providing opportunities for private industries to assist in the changes and for DOE, others to apply cleanup technologies, and it is essential that close institutional relations be established.

  14. Trip report for field visit to Fayetteville Shale gas wells.

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J. A.; Environmental Science Division

    2007-09-30

    This report describes a visit to several gas well sites in the Fayetteville Shale on August 9, 2007. I met with George Sheffer, Desoto Field Manager for SEECO, Inc. (a large gas producer in Arkansas). We talked in his Conway, Arkansas, office for an hour and a half about the processes and technologies that SEECO uses. We then drove into the field to some of SEECO's properties to see first-hand what the well sites looked like. In 2006, the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) made several funding awards under a program called Low Impact Natural Gas and Oil (LINGO). One of the projects that received an award is 'Probabilistic Risk-Based Decision Support for Oil and Gas Exploration and Production Facilities in Sensitive Ecosystems'. The University of Arkansas at Fayetteville has the lead on the project, and Argonne National Laboratory is a partner. The goal of the project is to develop a Web-based decision support tool that will be used by mid- and small-sized oil and gas companies as well as environmental regulators and other stakeholders to proactively minimize adverse ecosystem impacts associated with the recovery of gas reserves in sensitive areas. The project focuses on a large new natural gas field called the Fayetteville Shale. Part of the project involves learning how the natural gas operators do business in the area and the technologies they employ. The field trip on August 9 provided an opportunity to do that.

  15. PERSPECTIVE: The tripping points of sea level rise

    Science.gov (United States)

    Hecht, Alan D.

    2009-12-01

    When President Nixon created the US Environmental Protection Agency (EPA) in 1970 he said the environment must be perceived as a single, interrelated system. We are nowhere close to achieving this vision. Jim Titus and his colleagues [1] highlight one example of where one set of regulations or permits may be in conflict with another and where regulations were crafted in the absence of understanding the cumulative impact of global warming. The issue here is how to deal with the impacts of climate change on sea level and the latter's impact on wetland polices, clean water regulations, and ecosystem services. The Titus paper could also be called `The tripping points of sea level rise'. Titus and his colleagues have looked at the impact of such sea level rise on the east coast of the United States. Adaptive responses include costly large- scale investment in shore protection (e.g. dikes, sand replenishment) and/or ecosystem migration (retreat), where coastal ecosystems move inland. Shore protection is limited by available funds, while ecosystem migrations are limited by available land use. The driving factor is the high probability of sea level rise due to climate change. Estimating sea level rise is difficult because of local land and coastal dynamics including rising or falling land areas. It is estimated that sea level could rise between 8 inches and 2 feet by the end of this century [2]. The extensive data analysis done by Titus et al of current land use is important because, as they observe, `property owners and land use agencies have generally not decided how they will respond to sea level rise, nor have they prepared maps delineating where shore protection and retreat are likely'. This is the first of two `tripping points', namely the need for adaptive planning for a pending environmental challenge that will create economic and environment conflict among land owners, federal and state agencies, and businesses. One way to address this gap in adaptive management

  16. 直流开断技术的进展与新型直流断路器%Development of Modern DC Switching Technologies and New Type of DC Circuit Breaker

    Institute of Scientific and Technical Information of China (English)

    陈德桂

    2014-01-01

    The renaissance of DC system promotes the progress of DC interruption technologies.First of all,this paper introduced the new demands for DC switches according to its application area to be expanded,then the difference between DC and AC interruption characteristics was analyzed,especially,non-stable phenomena to quenching DC arc is shown in the region of small DC current interruption.Based on the above analysis,some new DC interruption technologies and new types of DC circuit breakers were presented,including permanent magnet circuit breaker without polarity;DC circuit breaker derived from AC;gas filled DC circuit breaker;DC circuit breaker with artificial current zero produced by self-excitation oscillation circuit.%提出了直流系统对直流开断的新要求,分析了直流开断与交流分断的区别。同时介绍了几种直流开断新技术与新型直流断路器,包括无极性直流断路器、由交流派生直流断路器、密封充气式直流开关、自励振荡人工零点直流断路器,理清了直流开断技术的进展。

  17. Analysis of Decomposition Products Due to Floating Potential Discharge in SF6 Circuit Breaker%SF6断路器内部悬浮电位放电产生的分解产物分析

    Institute of Scientific and Technical Information of China (English)

    杨韧; 吴水锋; 薛军; 菅永峰; 陈江韩; 孙志恒; 修士新

    2013-01-01

    Abnormal content of SO2 gas was detected in a 126 kV SF6 circuit breaker,which inferred a latent fault in this circuit breaker.Theoretical analysis and disassembling inspection of the circuit breaker indicated that this latent fault was due to floating potential discharge in this circuit breaker.This paper analyses the forming process of floating potential and its influence on the operating characteristics of the circuit breaker.And the generation mechanisms of gaseous and solid decomposition products of SF6 gas under floating potential discharge are discussed.%在某断路器SF6分解产物检测时发现SO2气体体积分数异常,判断该断路器存在潜伏性缺陷.通过理论分析并对断路器进行解体检查,最终判断该断路器的潜伏性缺陷为悬浮电位放电故障.笔者分析了悬浮电位的形成过程及其对断路器的影响,分析了SF6气体在悬浮电位放电下的气体以及固体分解组分的生成机理.

  18. 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. PMID:18634618

  19. 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.

  20. Photovoice as an evaluation tool for student learning on a field trip

    Science.gov (United States)

    Behrendt, Marc; Machtmes, Krisanna

    2016-05-01

    Background: Photovoice is one method that enables an educator to view an experience from a student's perspective. This study examined how teachers might use photovoice during an informal learning experience to understand the students' experiences and experiential gain. Design and methods: Participants in this study consisted of six students, three male and three female, ranging from ninth through twelfth grade at a rural Ohio high school, who attended a field trip to a biological field station for a four-day immersive science experience. Students were provided cameras to photograph what they believed was important, interesting, or significant during an immersive four-day science trip to a biological field station, individualizing their observations in ways meaningful to them, and enabling them to assimilate or accommodate the experiences to their schema. Results: Analysis identified five positive benefits to use photovoice as an evaluation tool: teachers were provided qualitative evidence to evaluate student interaction on the field trip; teachers could evaluate the students' photographs and captions to determine if the field trip met the learning objectives; students were empowered to approach the goals and objectives of the field trip by making the field trip personally relevant; students assimilated and accommodated the new observations and experiences to their own schema; students automatically reflected upon the learning experience as they captioned the photos. Conclusions: Through photovoice, the teachers were enabled to qualitatively assess each student's experience and learning from the field trip by illustrating what the students experienced and thought was significant; providing the teachers a method to evaluate all participating students, including those who are secretive or do not normally contribute to class discussions.

  1. Exploring the use of Virtual Field Trips with elementary school teachers: A collaborative action research approach

    Science.gov (United States)

    Scott, Jeffrey Lance

    This research examines how elementary school teachers, when supported, use Virtual Field Trips (VFTs) to address the curricula in meaningful ways. I conducted a qualitative study with six teachers, in a collaborative action research context over a six month period. The teachers, five males and one female, all taught either grade five or six and utilized Virtual Field Trips within a variety of curricula areas including science, social studies, music and language arts. In addition, the thesis examines resulting integration of technology into the regular classroom program as a product of the utilization of Virtual Field Trips. The process of collaborative action research was applied as a means of personal and professional growth both for the participants and the researcher/facilitator. By the end of the research study, all participants had learned to integrate Virtual Field Trips into their classroom program, albeit with different levels of success and in different curricula areas. The development of attitudes, skills and knowledge for students and teachers alike was fostered through the participation in Virtual Field Trips. A common concern regarding the utilization of Virtual Field Trips was the time spent locating an appropriate site that met curricula expectations. Participation in the collaborative action research process allowed each teacher to grow professionally, personally and socially. Each participant strongly encouraged the utilization of a long term project with a common area of exploration as a means for positive professional development. Implications and recommendations for future research on the utilization of Virtual Field Trips, as well as the viability of collaborative action research to facilitate teacher development are presented.

  2. Report on the safety related occurrences and reactor trips July 1, 1980 - December 31, 1980

    International Nuclear Information System (INIS)

    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, 1981 inclusive. The facilities involved are Barsebaeck 1 and 2, Oskarhamn 1 and 2, Ringhals 1, 2 and 3 and Forsmark 1 and 2. During this period of 6 months 88 safety related occurrences and 51 reactor trips have been reported to the Nuclear Power Inspectorate. As earlier experiences have shown 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 2,3 trips/unit if one looks at the 6 units in commercial operation. As can be expected, Ringhals 3 and Forsmark 1 have had significantly more reactor trips. These units have been in the start up phase during this period, which includes different transient and trip tests. Forsmark 2, beeing in its hot functional test period, has not yet been the subject of many of these tests. This is reflected in very few incidents and reactor trips. 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)

  3. Using Virtual Field Trips to Connect Students with University Scientists: Core Elements and Evaluation of zipTrips™

    Science.gov (United States)

    Adedokun, Omolola A.; Hetzel, Kristin; Parker, Loran Carleton; Loizzo, Jamie; Burgess, Wilella D.; Paul Robinson, J.

    2012-10-01

    Physical field trips to scientists' work places have been shown to enhance student perceptions of science, scientists and science careers. Although virtual field trips (VFTs) have emerged as viable alternatives (or supplements) to traditional physical fieldtrips, little is known about the potential of virtual field trips to provide the same or similar science career exploration advantages as physical field trips. The overarching goal of this paper is to describe a VFT, zipTrips™, designed to provide middle school students, especially those in resource limited rural areas, with access to university scientists. Using zipTrips as a case example, the paper identifies and describes some of the core characteristics and elements of high quality authentic VFTs that foster student-scientist interactions. In addition, the paper uses program evaluation data to examine the impact of zipTrips on student perceptions of scientists.

  4. Getting out and about in older adults: the nature of daily trips and their association with objectively assessed physical activity

    OpenAIRE

    Sharp Debbie J; Coulson Jo C; Hillsdon Melvyn; Fox Kenneth R; Davis Mark G; Stathi Afroditi; Thompson Janice L

    2011-01-01

    Abstract Background A key public health objective is increasing health-enhancing physical activity (PA) for older adults (OAs). Daily trip frequency is independently associated with objectively assessed PA volumes (OAs). Little is known about correlates and these trips' transport mode, and how these elements relate to PA. Purpose: to describe the frequency, purpose, and travel mode of daily trips in OAs, and their association with participant characteristics and objectively-assessed PA. Metho...

  5. Personal and trip characteristics associated with safety equipment use by injured adult bicyclists: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Teschke Kay

    2012-09-01

    Full Text Available Abstract Background The aim of this study was to estimate use of helmets, lights, and visible clothing among cyclists and to examine trip and personal characteristics associated with their use. Methods Using data from a study of transportation infrastructure and injuries to 690 adult cyclists in Toronto and Vancouver, Canada, we examined the proportion who used bike lights, conspicuous clothing on the torso, and helmets on their injury trip. Multiple logistic regression was used to examine associations between personal and trip characteristics and each type of safety equipment. Results Bike lights were the least frequently used (20% of all trips although they were used on 77% of trips at night. Conspicuous clothing (white, yellow, orange, red was worn on 33% of trips. Helmets were used on 69% of trips, 76% in Vancouver where adult helmet use is required by law and 59% in Toronto where it is not. Factors positively associated with bike light use included night, dawn and dusk trips, poor weather conditions, weekday trips, male sex, and helmet use. Factors positively associated with conspicuous clothing use included good weather conditions, older age, and more frequent cycling. Factors positively associated with helmet use included bike light use, longer trip distances, hybrid bike type, not using alcohol in the 6 hours prior to the trip, female sex, older age, higher income, and higher education. Conclusions In two of Canada’s largest cities, helmets were the most widely used safety equipment. Measures to increase use of visibility aids on both daytime and night-time cycling trips may help prevent crashes.

  6. 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

  7. Career-focused field trips as experienced by at-risk rural students: A case study

    Science.gov (United States)

    Hutson, Tommye L.

    A lack of recent research focused on field trips as pedagogy in K-12 settings established the foundation for this work. The research design followed multiple-case case study model. The participants were four male students from a small rural high school in central Texas. Each participant, previously labeled as academically "at-risk", had identified an inability to describe connections between academic science content as presented in their common classes and future jobs, vocational training, and/or careers requiring higher education. Because the participants had no directed field excursions addressing this desirable knowledge and/or skill, a career-focused field trip was designed to address the self-identified deficit reported by the participants. The specific research questions were: (1) How does the ability to describe connections between academic science content (biology, chemistry, and physics) and future careers change as rural students experience a purposeful excursion to a post-secondary facility providing vocational training? (2) When do the connection(s) between content and future careers become evident to students? (3) What effects or impact do newly discovered connections have on rural students' aspirations with regard to future career or higher education options? Data were gathered using existing school records, an initial survey, one-to-one interviews conducted before and after the field trip, focus groups conducted before and after the field trip, and observations during the field trip. Data analysis revealed that all participants were able to describe various connections between academic content and careers after the field trip, as well as identify a specific incident that initially established those connections. In addition, all of the participants reported discovering options for careers during the field trip not previously realized or considered. Each participant indicated that they found field trips to be effective. As a result of their singular

  8. Path Tracking Control of Vacuum Circuit Breaker%真空断路器循迹控制

    Institute of Scientific and Technical Information of China (English)

    秦涛涛; 董恩源; 陈宇硕; 段雄英; 邹积岩

    2014-01-01

    采用带自调整函数的模糊算法,能够使断路器永磁机构按给定曲线动作,保证断路器的合闸时间稳定,从而提高选相操作的精度。通过该算法可实时纠正断路器永磁机构的运动位移偏差,在电容电压、环境温度等外界因素发生变化时,使机构仍按给定曲线动作。通过开关特性测试仪和DSP2812硬件控制系统,得到标准位移曲线及控制算法中的基本参量值,并在 Matlab 中建立了考虑续流过程的真空断路器闭环控制系统,给出了电容电压变化的仿真结果,验证了上述控制方法的可行性。此外,针对单相配永磁机构真空断路器,进行大量的合闸实验。实验结果表明:在上述外界因素变化时,该控制方法能将断路器合闸时间稳定在±0.5 ms之内。%A fuzzy algorithm with self-turning function was proposed in this paper to make Permanent Magnetic Actuator (PMA) move along with the given displacement curve. Then the closing time of PMA is stable and the precision of phase-selection operation is improved. The deviation of displacement, caused by the variation of capacitor voltage and ambient temperature, can be corrected by the algorithm in real time. So PMA can still move along with the given displacement curve. The standard displacement curve and the basic parameters were obtained by the high-voltage switch testing equipment and hardware system DSP2812 respectively. Meanwhile, a closed-loop system, considering free-wheeling process of coil, was established in the software Matlab to verify the feasibility of the algorithm when the voltage of capacitor varied. In addition, a large number of tracing experiments have been done on the breakers and the results proved that closing time of breaker can be stabilized within±0.5ms under the condition of changing capacitor voltage and ambient temperature.

  9. Symptom clusters on primary care medical service trips in five regions in Latin America.

    Science.gov (United States)

    Dainton, Christopher; Chu, Charlene

    2015-09-01

    Short-term primary care medical service trips organized by the North American non-governmental organizations (NGOs) serve many communities in Latin America that are poorly served by the national health system. This descriptive study contributes to the understanding of the epidemiology of patients seen on such low-resource trips. An analysis was conducted on epidemiologic data collected from anonymized electronic medical records on patients seen during 34 short-term medical service trips in five regions in Ecuador, Guatemala, and the Dominican Republic between April 2013 and April 2014. A total of 22,977 patients were assessed by North American clinicians (physicians, nurse practitioners, physician assistants) on primary care, low-resource medical service trips. The majority of patients were female (67.1%), and their average age was 36. The most common presenting symptoms in all regions were general pain, upper respiratory tract symptoms, skin disorders, eye irritation, dyspepsia, and nonspecific abdominal complaints; 71-78% of primary care complaints were easily aggregated into well-defined symptom clusters. The results suggest that guideline development for clinicians involved in these types of medical service trips should focus on management of the high-yield symptom clusters described by these data.

  10. Mass Wasting Following the 2002 Missionary Ridge Fire near Durango, Colorado, a Field Trip Guidebook

    Science.gov (United States)

    Bigio, Erica R.; Blair, Robert W.; Burke, Michael; Cannon, Susan H.; deWolfe, Victor G.; Ey, John; Gartner, Joseph E.; Gillam, Mary L.; Knowlton, N.D.; Santi, Paul M.; Schulz, William H.; Coe, Jeffrey A.

    2007-01-01

    This field trip guide focuses on mass wasting following the 2002 Missionary Ridge fire near Durango, Colorado. We prepared this guide to accompany a May 4, 2006, field trip during the second Roy J. Shlemon Specialty Conference, which was held in Durango, Colorado, May 3-5. The conference, entitled Mass Wasting in Disturbed Watersheds, was sponsored by the Association of Environmental & Engineering Geologists (AEG) and the AEG Foundation. The objective of this Shlemon Conference was to bring together practitioners and researchers to define the current state of practice and identify unresolved problems with regard to the prediction and mitigation of mass wasting in disturbed watersheds. The one-day field trip begins and ends in Durango. Many of the field trip stops are at debris-flow fans around the periphery of the burn area, but one stop examines landslide activity in the burn area that initiated during spring 2005 snowmelt within a dormant, deep-seated landslide, as well as an erosion/debris-flow mitigation effort in a drainage basin above Lemon Reservoir. Also provided are descriptions of the Missionary Ridge fire, the geologic and climatic setting of the field-trip area, and the general effects of wildfire on watersheds.

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

    International Nuclear Information System (INIS)

    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)

  12. Active dorsiflexing prostheses may reduce trip-related fall risk in people with transtibial amputation

    Directory of Open Access Journals (Sweden)

    Noah J. Rosenblatt, PhD

    2015-01-01

    Full Text Available People with amputation are at increased risk of falling compared with age-matched, nondisabled individuals. This may partly reflect amputation-related changes to minimum toe clearance (MTC that could increase the incidence of trips and fall risk. This study determined the contribution of an active dorsiflexing prosthesis to MTC. We hypothesized that regardless of speed or incline the active dorsiflexion qualities of the ProprioFoot would significantly increase MTC and decrease the likelihood of tripping. Eight people with transtibial amputation walked on a treadmill with their current foot at two grades and three velocities, then repeated the protocol after 4 wk of accommodation with the ProprioFoot. A mixed-model, repeated-measures analysis of variance was used to compare MTC. Curves representing the likelihood of tripping were derived from the MTC distributions and a multiple regression was used to determine the relative contributions of hip, knee, and ankle angles to MTC. Regardless of condition, MTC was approximately 70% larger with the ProprioFoot (p < 0.001 and the likelihood of tripping was reduced. Regression analysis revealed that MTC with the ProprioFoot was sensitive to all three angles, with sensitivity of hip and ankle being greater. Overall, the ProprioFoot may increase user safety by decreasing the likelihood of tripping and thus the pursuant likelihood of a fall.

  13. Improving Confidence in Competencies for International Medical Trips Using a Curriculum with Simulation.

    Science.gov (United States)

    Birckhead, Brandon J; Mullikin, Trey C; Zubair, Adeel S; Alniemi, Dema; Franz, Walter B; Bachman, John W

    2015-01-01

    Many incoming medical and undergraduate students seek out international medical mission trips to supplement their education and training. However, few have the necessary skills to perform simple clinical tasks such as taking vital signs or conducting an initial patient interview. We conducted a small pilot study to assess the impact of simulation exercises on teaching incoming first-year medical students and undergraduate students basic clinical skills and teamwork. Our study population consisted of nine incoming medical students and 11 undergraduate students who participated in a training session involving simulated tasks prior to taking a medical mission trip to Nicaragua. Participants completed a survey before and after the simulation and at the end of the trip. All 20 indicated the simulation was effective in teaching clinical and team-building skills. In addition, the simulation exercise improved participants' confidence in their ability to perform certain clinical tasks and work as a team prior to the mission trip. We concluded that simulation is effective for incoming medical and undergraduate students and can be used prior to global health trips to increase their confidence in performing tasks required for a successful experience. PMID:26720942

  14. 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.

  15. TRIPS, the Doha Declaration and increasing access to medicines: policy options for Ghana

    Directory of Open Access Journals (Sweden)

    Torpey K

    2005-12-01

    Full Text Available Abstract There are acute disparities in pharmaceutical access between developing and industrialized countries. Developing countries make up approximately 80% of the world's population but only represent approximately 20% of global pharmaceutical consumption. Among the many barriers to drug access are the potential consequences of the Trade Related Aspects of Intellectual Property Rights (TRIPS Agreement. Many developing countries have recently modified their patent laws to conform to the TRIPS standards, given the 2005 deadline for developing countries. Safeguards to protect public health have been incorporated into the TRIPS Agreement; however, in practice governments may be reluctant to exercise such rights given concern about the international trade and political ramifications. The Doha Declaration and the recent Decision on the Implementation of Paragraph 6 of the Doha Declaration on the TRIPS Agreement and Public Health may provide more freedom for developing countries in using these safeguards. This paper focuses on Ghana, a developing country that recently changed its patent laws to conform to TRIPS standards. We examine Ghana's patent law changes in the context of the Doha Declaration and assess their meaning for access to drugs of its population. We discuss new and existing barriers, as well as possible solutions, to provide policy-makers with lessons learned from the Ghanaian experience.

  16. Eliciting management action: Using THERP to highlight human factors deficiencies for trip reduction programs

    International Nuclear Information System (INIS)

    Methods and criteria for performing human factors evaluations of plant systems and procedures are well developed and available. For a design review to produce a positive impact on operations, however, it is not enough to simply document deficiences and solutions. The results must be presented to management in a clear and compelling form that will direct attention to the heart of a problem and present proposed solutions in terms of explicit, quantified cost/benefits. A proactive program of trip reduction provides an excellent opportunity to accomplish human factors-related upgrades. As an evaluative context, trip reduction imposes a uniform goodness criterion on all situations: the probability of inadvertent plant trip. This in turn means that findings can be compared in terms of a common quantitative reference point: the cost of an inadvertent shutdown. To interpret human factors deficiencies in terms of trip probabilities, the Technique for Human Error Rate Prediction (THERP) can be used. THERP provides an accessible compilation of human reliability data for generic, discrete task elements. Sequences of such values are combined in standard event trees to determine the probability of failure (e.g., trip) for a given evolution. THERP is widely accepted as one of the best available alternatives for assessing human reliability

  17. 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.

  18. Measuring the relationship between sportfishing trip expenditures and anglers’ species preferences

    Science.gov (United States)

    Long, James M.; Melstrom, Richard T.

    2016-01-01

    We examined the relationship between fishing trip expenditures and anglers’ species preferences from a survey of Oklahoma resident anglers conducted in 2014. Understanding patterns in fishing trip expenditures is important because a significant share of state wildlife agency revenue comes from taxes on purchases of fishing equipment. Presently, there is little research that addresses the question of how spending levels vary within groups of sportspersons, including anglers. We used regression analysis to identify a relationship between trip spending and several preference variables, and included controls for other characteristics of fishing trips, such as location, party size, and duration. We received 780 surveys for a response rate of 26%, but only 506 were useable due to missing data or nonfishing responses. Average trip expenditures were approximately US$140, regardless of species preferences, but anglers who preferred to fish for trout and black bass tended to spend more than those who preferred to fish for catfish and panfish. These results were even more pronounced when location was considered, those who last fished at lakes spending more than those who fished at rivers or ponds. The results underscore the differences in spending among anglers with different preferred species and fishing locations.

  19. Influence of the gas flow rate on the nonchemical equilibrium N2 arc behavior in a model nozzle circuit breaker

    Science.gov (United States)

    Wu, Yi; Sun, Hao; Tanaka, Yasunori; Tomita, Kentaro; Rong, Mingzhe; Yang, Fei; Uesugi, Yoshihiko; Ishijima, Tatsuo; Wang, Xiaohua; Feng, Ying

    2016-10-01

    The influence of the gas flow rate on the N2 arc behavior was investigated based on a previously established nonchemical equilibrium (non-CE) model. This numerical non-CE model was adopted in the N2 nozzle arc in a model circuit breaker. The arc behaviors of both the arc burning and arc decay phases were obtained at different gas flow rates in both the non-CE and local thermal equilibrium (LTE) model. To better understand the influence of the gas flow rate, in this work we devised the concept of the nonequilibrium parameter. Additionally, the influences of convection, diffusion, and chemical reactions were examined separately to determine which one contributed most to the non-CE behavior. Finally, laser Thomson scattering (LTS) measurements at different gas flow rates were adopted to further demonstrate the validity of the non-CE model. The results of the macroscopic behaviors indicate that the deviations between the non-CE and LTE models during the arc burning phase are much fewer than those during the arc decay phase. By the nonequilibrium parameters, it clearly indicates that with an increase in the gas flow rate, the non-CE effect will be greatly enhanced. During the arc burning phase, this non-CE effect is mainly caused by radial diffusion of the particles. During the arc decay phase, for the charged particles, the chemical reactions had the greatest effect on the time variations of the particle number densities; however, for the neutral particles the time variations of the number densities were mutually influenced by convections, diffusions, and chemical reactions. Finally, the LTS results further demonstrate the validity of the non-CE model at different gas flow rates.

  20. TRIP: a novel double stranded RNA binding protein which interacts with the leucine rich repeat of flightless I.

    Science.gov (United States)

    Wilson, S A; Brown, E C; Kingsman, A J; Kingsman, S M

    1998-08-01

    A northwestern screen of a CHO-K1 cell line cDNA library with radiolabelled HIV-1 TAR RNA identified a novel TAR RNA interacting protein, TRIP. The human trip cDNA was also cloned and its expression is induced by phorbol esters. The N-terminus of TRIP shows high homology to the coiled coil domain of FLAP, a protein which binds the leucine-rich repeat (LRR) of Flightless I (FLI) and the interaction of TRIP with the FLI LRR has been confirmed in vitro . TRIP does not bind single stranded DNA or RNA significantly and binds double stranded DNA weakly. In contrast, TRIP binds double stranded RNA with high affinity and two molecules of TRIP bind the TAR stem. The RNA binding domain has been identified and encompasses a lysine-rich motif. A TRIP-GFP fusion is localised in the cytoplasm and excluded from the nucleus. FLI has a C-terminal gelsolin-like domain which binds actin and therefore the association of TRIP with the FLI LRR may provide a link between the actin cytoskeleton and RNA in mammalian cells. PMID:9671805

  1. Traveling to reach destination, or for the sake of it: a typology of trips after French national travel survey data

    OpenAIRE

    PAPON, Francis

    2012-01-01

    The purpose of this paper is to analyze the primary utility of travel (PUT) after data from the French National Travel Survey (FNTS) 2007-2008, to know how 'primary' actual trips are, or more exactly to what extent they yield each of three types of utility : utility of reaching a destination, utility of activities performed during the trip, and utility of the trip itself. For that, a twelve-fold typology of trips is created (PUT type). The paper provides one dimension statistics of all PUT...

  2. Getting out and about in older adults: the nature of daily trips and their association with objectively assessed physical activity

    Directory of Open Access Journals (Sweden)

    Sharp Debbie J

    2011-10-01

    Full Text Available Abstract Background A key public health objective is increasing health-enhancing physical activity (PA for older adults (OAs. Daily trip frequency is independently associated with objectively assessed PA volumes (OAs. Little is known about correlates and these trips' transport mode, and how these elements relate to PA. Purpose: to describe the frequency, purpose, and travel mode of daily trips in OAs, and their association with participant characteristics and objectively-assessed PA. Methods Participants (n = 214, aged 78.1 SD 5.7 years, completed a seven-day trips log recording daily-trip frequency, purpose and transport mode. Concurrently participants wore an accelerometer which provided mean daily steps (steps·d-1, and minutes of moderate to vigorous PA (MVPA·d-1. Participants' physical function (PF was estimated and demographic, height and weight data obtained. Results Trip frequency was associated with gender, age, physical function, walking-aid use, educational attainment, number of amenities within walking distance and cars in the household. Participants reported 9.6 (SD 4.2 trips per week (trips·wk-1. Most trips (61% were by car (driver 44%, passenger 17%, 30% walking or cycling (active and 9% public transport/other. Driving trips·wk-1 were more common in participants who were males (5.3 SD 3.6, well-educated (5.0 SD 4.3, high functioning (5.1 SD 4.6, younger (5.6 SD 4.9, affluent area residents (5.1 SD 4.2 and accessing > one car (7.2 SD 4.7. Active trips·wk-1 were more frequent in participants who were males (3.4 SD 3.6, normal weight (3.2 SD 3.4, not requiring walking aids (3.5 SD 3.3, well-educated (3.7 SD 0.7, from less deprived neighbourhoods (3.9 SD 3.9 and with ≥ 8 amenities nearby (4.4 SD 3.8. Public transport, and active trip frequency, were significantly associated with steps·d-1 (p -1 (p Conclusions Daily trips are associated with objectively-measured PA as indicated by daily MVPA and steps. Public transport and

  3. RESOLVE and ECO: Survey Design

    Science.gov (United States)

    Kannappan, Sheila; Moffett, Amanda J.; Norris, Mark A.; Eckert, Kathleen D.; Stark, David; Berlind, Andreas A.; Snyder, Elaine M.; Norman, Dara J.; Hoversten, Erik A.; RESOLVE Team

    2016-01-01

    The REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey is a volume-limited census of stellar, gas, and dynamical mass as well as star formation and galaxy interactions within >50,000 cubic Mpc of the nearby cosmic web, reaching down to dwarf galaxies of baryonic mass ~10^9 Msun and spanning multiple large-scale filaments, walls, and voids. RESOLVE is surrounded by the ~10x larger Environmental COntext (ECO) catalog, with matched custom photometry and environment metrics enabling analysis of cosmic variance with greater statistical power. For the ~1500 galaxies in its two equatorial footprints, RESOLVE goes beyond ECO in providing (i) deep 21cm data with adaptive sensitivity ensuring HI mass detections or upper limits deep NUV coverage and synergy with other equatorial surveys as well as unique northern and southern facilities such as Arecibo, the GBT, and ALMA. The RESOLVE and ECO surveys have been supported by funding from NSF grants AST-0955368 and OCI-1156614.

  4. Transforming medical imaging: the first SCAR TRIP conference a position paper from the SCAR TRIP subcommittee of the SCAR research and development committee.

    Science.gov (United States)

    Andriole, Katherine P; Morin, Richard L

    2006-03-01

    The First Society for Computer Applications in Radiology (SCAR) Transforming the Radiological Interpretation Process (TRIP) Conference and Workshop, "Transforming Medical Imaging" was held on January 31-February 1, 2005 in Bethesda, MD. Representatives from all areas of medical and scientific imaging-academia, research, industry, and government agencies-joined together to discuss the future of medical imaging and potential new ways to manage the explosion in numbers, size, and complexity of images generated by today's continually advancing imaging technologies. The two-day conference included plenary, scientific poster, and breakout sessions covering six major research areas related to TRIP. These topic areas included human perception, image processing and computer-aided detection, data visualization, image set navigation and usability, databases and systems integration, and methodology evaluation and performance validation. The plenary presentations provided a general status review of each broad research field to use as a starting point for discussion in the breakout sessions, with emphasis on specific topics requiring further study. The goals for the breakout sessions were to define specific research questions in each topic area, to list the impediments to carrying out research in these fields, to suggest possible solutions and near- and distant-future directions for each general topic, and to report back to the general session. The scientific poster session provided another mechanism for presenting and discussing TRIP-related research. This report summarizes each plenary and breakout session, and describes the group recommendations as to the issues facing the field, major impediments to progress, and the outlook for radiology in the short and long term. The conference helped refine the definition of the SCAR TRIP Initiative and the problems facing radiology with respect to the dramatic growth in medical imaging data, and it underscored a present and future need

  5. 虚拟样机技术在断路器优化中的应用研究%Application Study of Virtual Prototype Technology in Optimization of Circuit Breakers

    Institute of Scientific and Technical Information of China (English)

    于永站; 张金泉; 孙永雷; 陈大江

    2012-01-01

      以 KFW2系列万能式断路器为列,介绍了虚拟样机技术在断路器优化中的应用,利用 ADAMS软件建立断路器虚拟样机模型,对断路器的运动情况进行仿真,模拟了实物样机的真实运动情况,得到断路器各部件在分离、试验、连接位置时的行程数据,并给出了关键部件在试验和连接位置时的行程范围。通过分析结果表明,虚拟样机技术对低压断路器的优化提供了新的技术途径%  Taking KFW2 series open-construction circuit breaker as an example, this paper introduced the application of virtual prototype technology in circuit-breaker optimization. ADAMS software was used to build up a circuit-breaker virtual prototype model to carry out simulation for movement conditions of circuit breakers. The real movement conditions of actual prototype was simulated to get the travel data of circuit-breaker each component at separating, test, contact positions and travel ranges of key components at test and contact positions were given. The results of analysis show that virtual prototype technology has provided new technology path for low-voltage circuit-breaker optimization.

  6. 南阳特高压断路器失灵保护的研究%Study on Nanyang substation of UHV circuit breaker failure protection

    Institute of Scientific and Technical Information of China (English)

    姜自强; 刘建勇

    2015-01-01

    晋东南-南阳-荆门特高压示范工程的正式投运标识着特高压电网的建设已进入快速发展阶段,但是特高压二次系统时间常数的增大使得CT拖尾现象变得不可忽视。一方面,对特高压断路器 CT电流互感器的选型提出了新的问题,只选择TPY次级则会进一步恶化CT拖尾现象,选择P次级则增加成本。另一方面,CT拖尾对断路器失灵保护的正确动作造成了负面的影响。针对该情况,对特高压3/2断路器接线方式下断路器的失灵保护进行了研究,并提出一种针对性的改进方案。通过对比分析、仿真实验以及数模实验结果,证明该修改方案是切实可行的。既能有效地解决特高压断路器 CT电流互感器的选型问题,也能有效地解决 CT拖尾对失灵保护的危害问题。%The formal commissioning Jindongnan-Nanyang-Jingmen UHV demonstration project identifies that the construction of special high-voltage power grid has entered a rapid development stage, but the increase of UHV two system time constant makes the CT become tailing phenomenon can not be ignored. On the one hand, it puts forward a new problem for the selection of UHV circuit breaker CT current transformer, namely selecting only the TPY secondary will deteriorate further CT tailing phenomenon and selecting the P secondary will increase the cost. On the other hand, CT trailing influences breaker failure protection, making it unable to right action. In view of this situation, it studies the failure protection under the wiring mode of 3/2 breaker in UHV and proposes an improved scheme. The contrast analysis, simulation and RTDS experimental results prove that the modified scheme is feasible, which can both effectively solve the problems of the selection of UHV circuit breaker CT current transformer and CT tailing hazard failure protection.

  7. Selection of Circuit Breaker at the Outlet of LV Diesel Generator%低压柴油发电机出口处断路器的选择

    Institute of Scientific and Technical Information of China (English)

    蒋炜栋; 王坚

    2013-01-01

    介绍柴油发电机短路电流的计算方法;计算某柴油发电机的短路电流;利用计算结果选择此柴油发电机出口处断路器。%This paper introduces the calculation method of short circuit current of diesel generator, calculates the short circuit current of the diesel generator, and selects the circuit breaker at the outlet of diesel generator based on the calculation results.

  8. Resolvability of positron decay channels

    International Nuclear Information System (INIS)

    Many data analysis treatments of positron experiments attempt to resolve two or more positron decay or exist channels which may be open simultaneously. Examples of the need to employ such treatments of the experimental results can be found in the resolution of the constituents of a defect ensemble, or in the analysis of the complex spectra which arise from the interaction of slow positrons at or near the surfaces of solids. Experimental one- and two-dimensional angular correlation of annihilation radiation experiments in Al single crystals have shown that two defect species (mono- and divacancies) can be resolved under suitable conditions. Recent experiments at LLNL indicate that there are a variety of complex exit channels open to positrons interacting at surfaces, and ultimely these decay channels must also be suitably resolved from one another. 6 refs., 4 figs

  9. Resolving Boosted Jets with XCone

    CERN Document Server

    Thaler, Jesse

    2015-01-01

    We show how the recently proposed XCone jet algorithm smoothly interpolates between resolved and boosted kinematics. When using standard jet algorithms to reconstruct the decays of hadronic resonances like top quarks and Higgs bosons, one typically needs separate analysis strategies to handle the resolved regime of well-separated jets and the boosted regime of fat jets with substructure. XCone, by contrast, is an exclusive cone jet algorithm that always returns a fixed number of jets, so jet regions remain resolved even when (sub)jets are overlapping in the boosted regime. In this paper, we perform three LHC case studies---dijet resonances, Higgs decays to bottom quarks, and all-hadronic top pairs---that demonstrate the physics applications of XCone over a wide kinematic range.

  10. Effect of Controlled Cooling After Hot Rolling on Mechanical Properties of Hot Rolled TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    WU Di; LI Zhuang; L(U) Hui-sheng

    2008-01-01

    A three-step cooling pattern on the runout table (ROT) was conducted for the hot rolled TRIP steel. Microstructural evolution during thermomechanical controlled processing (TMCP) was investigated. Proeessing condition of controlled cooling on a ROT in the laboratory rolling mill was discussed. The results indicated that the microstructure containing polygonal ferrite, granular bainite and a significant amount of the stable retained austenite can be obtained through three-step cooling on the ROT after hot rolling. TMCP led to ferrite grain refinement. Controlled cooling after hot rolling resulted in the stability of the remaining austenite and a satisfactory TRIP effect. Excellent mechanical properties were obtained through TMCP for the hot rolled TRIP steel.

  11. Determining the Characteristics of Trips Generated on Southern Bali using Category Analysis

    Directory of Open Access Journals (Sweden)

    I Wayan Suweda

    2011-11-01

    Full Text Available Southern Bali, a tourism center of Indonesia, has been rapidly developed. Unfortunately, the development is not followed simultaneously by the development of adequate transportation network, as a result, traffic congestion are inevitably occurred along every urban road in the district. Therefore integrated development and regional transport planning therefore, is urgently required. In this study, trip generation is determined using Category Analysis. It is Figured out from the household based interview that Denpasar Barat zones are found to have the largest trip generation while Pecatu zones are found to be the smallest. Most of the household trips generated use private vehicles (94.95% and the rest uses public transport. This also indicates that public transport services in Southern Bali still need to be developed.

  12. Method and apparatus for optimizing a train trip using signal information

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Ajith Kuttannair; Daum, Wolfgang; Otsubo, Tom; Hershey, John Erik; Hess, Gerald James

    2014-06-10

    A system is provided for operating a railway network including a first railway vehicle during a trip along track segments. The system includes a first element for determining travel parameters of the first railway vehicle, a second element for determining travel parameters of a second railway vehicle relative to the track segments to be traversed by the first vehicle during the trip, a processor for receiving information from the first and the second elements and for determining a relationship between occupation of a track segment by the second vehicle and later occupation of the same track segment by the first vehicle and an algorithm embodied within the processor having access to the information to create a trip plan that determines a speed trajectory for the first vehicle. The speed trajectory is responsive to the relationship and further in accordance with one or more operational criteria for the first vehicle.

  13. TripNet: A Method for Constructing Phylogenetic Networks from Triplets

    CERN Document Server

    Tusserkani, Ruzbeh; Poormohammadi, Hadi; Azadi, Azin

    2011-01-01

    We present TripNet, a method for constructing phylogenetic networks from triplets. We will present the motivations behind our approach and its theoretical and empirical justification. To demonstrate the accuracy and efficiency of TripNet, we performed two simulations and also applied the method to five published data sets: Kreitman's data, a set of triplets from real yeast data obtained from the Fungal Biodiversity Center in Utrecht, a collection of 110 highly recombinant Salmonella multi-locus sequence typing sequences, and nrDNA ITS and cpDNA JSA sequence data of New Zealand alpine buttercups of Ranunculus sect. Pseudadonis. Finally, we compare our results with those already obtained by other authors using alternative methods. TripNet, data sets, and supplementary files are freely available for download at (www.bioinf.cs.ipm.ir/softwares/tripnet).

  14. Influence of DC Supply Systems on Unplanned Reactor Trips in Nuclear Power Plants

    Institute of Scientific and Technical Information of China (English)

    李君利; 童节娟; 茆定远

    2001-01-01

    Operational experience has shown that some components in nuclearpower plants are so important that their failures, which would be a single failure, may cause the entire plant to shutdown. Such shutdowns have often occurred in the past in commercial nuclear power plants. Nuclear power plant authorities try to avoid such unplanned plant shutdowns because of the large economic loss. Unfortunately, it is difficult to identify all the important components from the numerous components in each complex nuclear power plant system. FMEA and FTA methods, which are often applied to probabilistic risk assessments, are used in this paper to identify the key components that may cause unplanned reactor trips. As an example, the 48 V DC power supply system in a typical Chinese nuclear power plant, which is a major cause of many unplanned reactor trips, was analyzed to show how to identify these key components and the causes for nuclear power plant trips.

  15. 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.

  16. Revealing daily travel patterns and city structure with taxi trip data

    CERN Document Server

    Liu, Xi; Gong, Yongxi; Liu, Yu

    2013-01-01

    Detecting regional spatial structures based on spatial interactions is crucial in applications ranging from urban planning to traffic control. In the big data era, various movement trajectories are available for studying spatial structures. This research uses large scale Shanghai taxi trip data extracted from GPS-enabled taxi trajectories to reveal traffic flow patterns and urban structure of the city. Using the network science methods, 15 temporally stable regions reflecting the scope of people's daily travels are found using community detection method on the network built from short trips, which represent residents' daily intra-urban travels and exhibit a clear pattern. In each region, taxi traffic flows are dominated by a few 'hubs' and 'hubs' in suburbs impact more trips than 'hubs' in urban areas. Land use conditions in urban regions are different from those in suburban areas. Additionally, 'hubs' in urban area associate with office buildings and commercial areas more, whereas residential land use is mor...

  17. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. Also included are a number of enforcement actions that had been previously resolved but not published in this NUREG. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  18. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1990) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. Also included are a number of enforcement actions that had been previously resolved but not published in this NUREG. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  19. Fluorescence Visualization of Hypersonic Flow Past Triangular and Rectangular Boundary-layer Trips

    Science.gov (United States)

    Danehy, Paul M.; Garcia, A. P.; Borg, Stephen E.; Dyakonov, Artem A.; Berry, Scott A.; Inman, Jennifer A.; Alderfer, David W.

    2007-01-01

    Planar laser-induced fluorescence (PLIF) flow visualization has been used to investigate the hypersonic flow of air over surface protrusions that are sized to force laminar-to-turbulent boundary layer transition. These trips were selected to simulate protruding Space Shuttle Orbiter heat shield gap-filler material. Experiments were performed in the NASA Langley Research Center 31-Inch Mach 10 Air Wind Tunnel, which is an electrically-heated, blowdown facility. Two-mm high by 8-mm wide triangular and rectangular trips were attached to a flat plate and were oriented at an angle of 45 degrees with respect to the oncoming flow. Upstream of these trips, nitric oxide (NO) was seeded into the boundary layer. PLIF visualization of this NO allowed observation of both laminar and turbulent boundary layer flow downstream of the trips for varying flow conditions as the flat plate angle of attack was varied. By varying the angle of attack, the Mach number above the boundary layer was varied between 4.2 and 9.8, according to analytical oblique-shock calculations. Computational Fluid Dynamics (CFD) simulations of the flowfield with a laminar boundary layer were also performed to better understand the flow environment. The PLIF images of the tripped boundary layer flow were compared to a case with no trip for which the flow remained laminar over the entire angle-of-attack range studied. Qualitative agreement is found between the present observed transition measurements and a previous experimental roughness-induced transition database determined by other means, which is used by the shuttle return-to-flight program.

  20. Surface Selective Oxidation of Sn-Added CMnSi TRIP Steel

    Science.gov (United States)

    Cho, Lawrence; Seo, Eun Jung; Jung, Geun Su; Suh, Dong Woo; De Cooman, Bruno C.

    2016-04-01

    The influence of the addition of Sn on the selective oxidation and the reactive wetting of CMnSi transformation-induced plasticity (TRIP) steels was studied by means of galvanizing simulator tests. A reference TRIP steel and TRIP steels containing Sn in the range of 0.05 to 1 wt pct were intercritically annealed at 1093 K (820 °C) in an N2+ 5 pct H2 gas atmosphere with a dew point of -60 °C. The thin-film oxides formed on the surface of the Sn-added CMnSi TRIP steel were investigated using transmission electron microscopy and 3-dimensional atom probe tomography. The addition of Sn (≥0.05 wt pct) changed the morphology of the xMnO·SiO2 surface oxides from a continuous film morphology to a lens-shaped island morphology. It also suppressed the formation of the Mn-rich oxides of MnO and 2MnO·SiO2. The changes in the morphology and chemistry of the surface oxides were clearly related to the surface segregation of Sn, which appeared to result in a decrease of the oxygen permeability at the surface. The formation of lens-shaped oxides improved the wettability of the CMnSi TRIP steel surface by the molten Zn. The improved wetting effect was attributed to an increased area fraction of the surface where the oxide layer was thinner. This enabled a direct, unhindered reaction between Fe and the Al in the liquid Zn and the formation of the inhibition layer in the initial stages of the hot dipping. The addition of a small amount of Sn was also found to decrease significantly the density of Zn-coating defects on CMnSi TRIP steel.

  1. 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.

  2. 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.

  3. Fire and Water Make Steam - Redefining the Role of Competition Law in TRIPS

    DEFF Research Database (Denmark)

    Schovsbo, Jens Hemmingsen

    that the weakness of the competition rules in TRIPS may be counterproductive towards the broader goals of IPR protection. From a development point of view it is pointed out that an effective and well function market is necessary in order for developing countries to reap any benefits arising out of IPR protection....... To innovation it is submitted that IPR protection e.g. of interfaces or in markets characterised by network effects may involve risks of monopolisation which require access to effective rules of competition law. The paper finally recommends concrete changes to TRIPS in the form of mandatory rules which prevent...

  4. Review and evaluation of models that produce trip tables from ground counts

    OpenAIRE

    Sivanandan, R.; Narayanan, Arvind; Lei, Peng

    1996-01-01

    This research effort was motivated by the desires of planning agencies to seek alternative methods of deriving current or base year Origin-Destination (O-D) trip tables without adopting conventional O-D surveys that are expensive, time consuming and labor intensive. This study had two objectives: (t) to conduct a review of existing approaches and models that produce trip tables from ground counts, and to select a few models for testing and evaluation, and (2) to perform a detailed testing of ...

  5. Development of a Hiking Trip for a Company Called Finlandia Natur

    OpenAIRE

    Marti Cardenas, Judit

    2013-01-01

    The aim of this thesis was to create a nature-based hiking tourism product for Finlandia Natur, the commissioner, which aims to expand their product range and thus attract new customers by developing a hiking trip program for its nature-based products. The research tasks of this thesis were the following: How was the program for a nature-based hiking trip developed, and why had the product to be tested? The first section of this thesis defines nature-based tourism and its different forms,...

  6. Research on Retained Austenite for Advanced Aluminum-containing Hot-rolled TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    Guoyi TANG; Fangyu CHEN; Pinghe LI; Sunbing ZHOU

    2005-01-01

    A new type of hot-rolled transformation induced plasticity (TRIP) steel with 2.3%Al was developed to replace conventional Si-bearing TRIP steel to improve surface quality of the steel sheet. The relationship between retained austenite volume fraction and hot-rolling processing was researched by Gleeble-2000 thermo-dynamic test for the Al-bearing steel. The experimental result showed that aluminum played an important role on retaining austenite and the volume fraction increased from 4.4% to 7.5% as coiling temperature increased from 350℃ to 450℃, while coiling temperature had a stronger effect on retaining austenite than finishing rolling temperature.

  7. EFFECTS OF CARBON CONTENT AND ROLLING PROCESSING ON RETAINED AUSTENITE FOR HOT-ROLLED TRIP STEELS

    Institute of Scientific and Technical Information of China (English)

    Y. Chen; X. Chen; Z.X. Yuan; B.F. Xu; A.M. Guo; P.H. Li; S.K. Pu

    2002-01-01

    The effects of finishing rolling temperature and coiling temperature on retained austen-ire were studied for hot-rolled transformation induced plasticity (TRIP) steels withdifferent carbon content. The experimental results showed that an appropriate volumefraction of retained austenite from 6% to 11% could be obtained according to the dif-ferent carbon content less than 0.20% by controlled finishing rolling and coiling forthe hot-rolled TRIP steels. It can be concluded that carbon content has a significanteffect on the fraction of retained austenite and coiling processing plays stronger roleon retaining austenite than fishing rolling processing.

  8. Effect of Silicon and Manganese on Mechanical Properties of Low-Carbon Plain TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    LI Zhuang; WU Di; HU Rong

    2005-01-01

    A great deal of stabilized retained austenite can be obtained by means of austempering immediately after intercritical annealing in the low-carbon plain steel sheets which only contain alloying elements of silicon and manganese. Transformation from retained austenite to martensite may be induced by strain at a temperature ranging from 50 ℃ to 400 ℃ during tension testing. Transformation-induced plasticity (TRIP) may occur. Alloying of silicon improves the stability of retained austenite. Mechanical properties of the present TRIP steels containing manganese increase with increasing silicon amount when the amount of silicon is less than two percent.

  9. Value creation through online travel reviews on TripAdvisor: case of hotels in Helsinki

    OpenAIRE

    Sjöblom, Sini

    2013-01-01

    The use of online travel reviews as a part of consumers' tourism planning processes is a growing phenomenon. Consumers' especially use other travelers' reviews while choosing accommodation for their trip. TripAdvisor is one of the largest tourism related websites on Internet and it contains reviews of hotels around the world. In this thesis the ways in which the hotels in Helsinki are using these reviews in their value creation processes, if they are used at all, are analyzed. Also based on t...

  10. Co-ordinated emergency control of generator-tripping and SMES based on Hamiltonian system theory

    Energy Technology Data Exchange (ETDEWEB)

    Jiangnan Peng [China Power Investment Corp., Beijing (China); Yuanzhang Sun [Tsinghua Univ., Dept. of Electrical Engineering, Beijing (China); Wang, H.F. [Bath Univ., Dept. of Electronic and Electrical Engineering, Bath (United Kingdom)

    2005-07-01

    This paper presents a novel scheme for the co-ordinated emergency control of generator-tripping control and Super-conducting Magnetic Energy Storage (SMES). The mathematical foundation of the scheme is based on the proposal of a new Lyapunov function of power systems transient stability analysis derived according to the Hamiltonian systems theory, which is used to quantitatively estimate the necessary control capacity to maintain power system transient stability via the co-ordination of generator-tripping and SMES control in system contingency. Simulation results to test the scheme are presented in the paper. (Author)

  11. TIME-RESOLVED VIBRATIONAL SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    Andrei Tokmakoff, MIT (Conference Chair); Paul Champion, Northeastern University; Edwin J. Heilweil, NIST; Keith A. Nelson, MIT; Larry Ziegler, Boston University

    2009-05-14

    This document contains the Proceedings from the 14th International Conference on Time-Resolved Vibrational Spectroscopy, which was held in Meredith, NH from May 9-14, 2009. The study of molecular dynamics in chemical reaction and biological processes using time-resolved spectroscopy plays an important role in our understanding of energy conversion, storage, and utilization problems. Fundamental studies of chemical reactivity, molecular rearrangements, and charge transport are broadly supported by the DOE’s Office of Science because of their role in the development of alternative energy sources, the understanding of biological energy conversion processes, the efficient utilization of existing energy resources, and the mitigation of reactive intermediates in radiation chemistry. In addition, time-resolved spectroscopy is central to all five of DOE’s grand challenges for fundamental energy science. The Time-Resolved Vibrational Spectroscopy conference is organized biennially to bring the leaders in this field from around the globe together with young scientists to discuss the most recent scientific and technological advances. The latest technology in ultrafast infrared, Raman, and terahertz spectroscopy and the scientific advances that these methods enable were covered. Particular emphasis was placed on new experimental methods used to probe molecular dynamics in liquids, solids, interfaces, nanostructured materials, and biomolecules.

  12. Time-resolved quantitative phosphoproteomics

    DEFF Research Database (Denmark)

    Verano-Braga, Thiago; Schwämmle, Veit; Sylvester, Marc;

    2012-01-01

    proteins involved in the Ang-(1-7) signaling, we performed a mass spectrometry-based time-resolved quantitative phosphoproteome study of human aortic endothelial cells (HAEC) treated with Ang-(1-7). We identified 1288 unique phosphosites on 699 different proteins with 99% certainty of correct peptide...

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

    Institute of Scientific and Technical Information of China (English)

    Vahid ABBASI; Ahmad GHOLAMI; Kaveh NIAYESH

    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 aria- lyzing the phenomenon. The coupled interactions between arc and plasma flow are described in the fl'amework of time-dependent magnetohydrodynamic (MHD) equations in conjunction with a K-~ 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 sjm- ulation 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.

  14. 络筒机智能防叠装置的研究%Sudy on intelligent ribboning breaker of a winder

    Institute of Scientific and Technical Information of China (English)

    王元昌; 薛卫; 肖荣

    2002-01-01

    现有的络筒机防叠装置不管有无重叠发生都按预设的周期作防叠动作,所以有多余的动作,又不能完全消除重叠.针对这一问题,笔者开发了智能防叠装置.这一装置在发生重叠时做防叠动作,否则络简机保持满速度运转.文中导出了纱圈重叠的条件,设计了微机的软件与硬件系统.%The ribboning breaker in a winder available does the anti-ribboning motion according to the preset-up period whatever ribboing or not. So there are motions to be unnecessary, moreover, it cannot eliminate the ribboning completely. Intelligent ribboning breaker does an anti-ribboning motion when produced ribboning, otherwise the winder keeps running fully. In this paper, the yarn loops ribboning conditions are deduced. Each spindle is controlled by a single-chip microcomputer to determine whether the yarn loop or not according to the ribboning conditions every yarn traverse to and fro, and to control the motor driving the grooved drum to change its rotational speed. The hardware and software design are written.

  15. Learning on Zoo Field Trips: The Interaction of the Agendas and Practices of Students, Teachers, and Zoo Educators

    Science.gov (United States)

    Davidson, Susan Kay; Passmore, Cynthia; Anderson, David

    2010-01-01

    This paper reports on the findings of a case study that investigated the interaction of the agendas and practices of students, teachers, and zoo educators during a class field trip to a zoo. The study reports on findings of the analysis of two case classes of students and their perceptions of their learning experiences during the field trip. The…

  16. Field Trip to the Moon. LRO/LCROSS Edition. Informal Educator's Guide. EG-2008-09-48-MSFC

    Science.gov (United States)

    National Aeronautics and Space Administration (NASA), 2007

    2007-01-01

    Field Trip to the Moon uses an inquiry-based learning approach that fosters team building and introduces participants to careers in science and engineering. The program components include the Field Trip to the Moon DVD [not included here], Lunar Reconnaissance Orbiter (LRO)/Lunar Crater Observation and Sensing Satellite (LCROSS) Activities, and…

  17. Thyroid hormone receptor interacting protein 13 (TRIP13) AAA-ATPase is a novel mitotic checkpoint-silencing protein.

    Science.gov (United States)

    Wang, Kexi; Sturt-Gillespie, Brianne; Hittle, James C; Macdonald, Dawn; Chan, Gordon K; Yen, Tim J; Liu, Song-Tao

    2014-08-22

    The mitotic checkpoint (or spindle assembly checkpoint) is a fail-safe mechanism to prevent chromosome missegregation by delaying anaphase onset in the presence of defective kinetochore-microtubule attachment. The target of the checkpoint is the E3 ubiquitin ligase anaphase-promoting complex/cyclosome. Once all chromosomes are properly attached and bioriented at the metaphase plate, the checkpoint needs to be silenced. Previously, we and others have reported that TRIP13 AAA-ATPase binds to the mitotic checkpoint-silencing protein p31(comet). Here we show that endogenous TRIP13 localizes to kinetochores. TRIP13 knockdown delays metaphase-to-anaphase transition. The delay is caused by prolonged presence of the effector for the checkpoint, the mitotic checkpoint complex, and its association and inhibition of the anaphase-promoting complex/cyclosome. These results suggest that TRIP13 is a novel mitotic checkpoint-silencing protein. The ATPase activity of TRIP13 is essential for its checkpoint function, and interference with TRIP13 abolished p31(comet)-mediated mitotic checkpoint silencing. TRIP13 overexpression is a hallmark of cancer cells showing chromosomal instability, particularly in certain breast cancers with poor prognosis. We suggest that premature mitotic checkpoint silencing triggered by TRIP13 overexpression may promote cancer development.

  18. Effect of Microstructure in TRIP Steel on Its Tensile Behavior at High Strain Rate

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The relationships between microstructure of 0.195C-1.6Si-1.58Mn TRIP steel and its dynamic mechanical properties at high strain rate were investigated. The effect of microstructures on dynamic properties was discussed and the comparison with its static mechanical properties was also presented. The specimens of TRIP steel via three heat treatment techniques exhibit different morphological structures, responsible for their dynamic mechanical performances. The dynamic tensile testing was performed on self-made pneumatic tensile impact tester. The results showed that the size, volume fraction, morphology and distribution of retained austenite all affect the final mechanical properties at high strain rate. Among them, the second phase (retained austenite+bainite) with net structure severely decreases the elongation of TRIP steel in spite of the fact that it enhances strength because it restrains ferrite deformation. In order to obtain the excellent combination of strength and elongation, rational matching of morphology, size and volume fraction of several phases in TRIP steel can be obtained via proper heat treatment techniques.

  19. The influence of drawing speed on properties of TRIP steel wires

    Directory of Open Access Journals (Sweden)

    M. Suliga

    2008-02-01

    Full Text Available Purpose: The aim of this paper is to determine the influence of drawing speed of TRIP steel wires on their properties.Design/methodology/approach: The heat treatment of steel containing 0.09 % carbon, 1.57 % manganese and 0.9 % silicon allows to obtain TRIP type structure. The wires were drawn with different drawing speed. After drawing mechanical properties of wires were determined by the tensile test. In this work also FEM modelling was done.Findings: The analysis of changes of mechanical properties after particular drawings stages was carried out. The increase of drawing speed cause the increase of strength properties and decreasing of plasticity properties of wires. It was shown that increase of drawing speed causes increase of: temperature, non-dilatation strain and internal stresses.Research limitations/implications: Continuation of the investigations with the use of scanning and transmission electron microscopy makes it possible to explain the changes properties of drawn wires by analyses of structure of drawn wires.Practical implications: TRIP steel wires, which have good mechanical properties and are dependent on drawing speed, can be used for production of connecting elements.Originality/value: For the first time there was shown the influence of drawing speed on properties of TRIP steel wires.

  20. 78 FR 53486 - Addition of Round-Trip Mailer Product to the Competitive Product List

    Science.gov (United States)

    2013-08-29

    ... Commission to add a product called ``Round-Trip Mailer'' to the competitive product list. DATES: Effective..., instructional document, or advertisement that conforms to the exceptions or suspensions in the Private Express.... The changes in price and class set forth therein shall be effective September 30, 2013, assuming...

  1. Learning by Doing: A City Trip Combining TBLLT, Blended Learning and Social Media

    Science.gov (United States)

    Stevens, Leen; Grisez, Viviane

    2014-01-01

    For several years, the University of MONS (UMONS) has been organising a trip to a Flemish city, either Leuven, Ghent, or Antwerp, for the students on the Masters programmes at the Faculty of Engineering who attend Dutch courses. This project has been combining blended learning and task-based learning for several years, but for the most recent…

  2. Utilizing Geo-Referenced Mobile Game Technology for Universally Accessible Virtual Geology Field Trips

    Science.gov (United States)

    Bursztyn, Natalie; Pederson, Joel; Shelton, Brett; Walker, Andrew; Campbell, Todd

    2015-01-01

    Declining interest and low persistence is well documented among undergraduate students in Science, Technology, Engineering, and Math in the United States. For geoscience, field trips are important attractors to students, however with high enrollment courses and increasing costs they are becoming rare. We propose in this concept paper that the…

  3. To the End of the World and Back: A Primer for International Study Trips

    Science.gov (United States)

    Fox, Terry L.; King, James; Reina, Michelle

    2014-01-01

    Global engagement is a move by many colleges and universities to broaden the perspectives of their students. Often, this is manifest in the form of short or longer-term study abroad trips. There is considerable excitement associated with traveling abroad on the part of both the students and the faculty sponsors, but one thing that must be…

  4. Report on safety related occurrences and reactor trips July 1, 1977 - December 31, 1977

    International Nuclear Information System (INIS)

    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

  5. Let's Go to Market! Field Trips to Discover Economics and Cultures

    Science.gov (United States)

    Gomez, Diana

    2010-01-01

    In this article, the author describes how her first grade class embarked on a journey of learning through a unit of study about local food markets. The study was a rich exploration of the cultural diversity of the city of Philadelphia, Pennsylvania, as well as an introduction to basic concepts about economics. Through their trips to a farm and…

  6. 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.

  7. The Impact of Immersion Trips on Development of Compassion among College Students

    Science.gov (United States)

    Plante, Thomas G.; Lackey, Katy; Hwang, Jeong Yeon

    2009-01-01

    The purpose of this study was to examine the possible enhancement of compassion in college students as a result of participating in community-based learning immersion trips. In two separate experiments, a total of 123 college students were given a series of questionnaires immediately before and after university-sponsored immersion experiences to…

  8. River Trip Optimization Scheduling Based on Artificial Intelligence Simulation and the Bee-Swarm Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Zhan Wenting

    2012-09-01

    Full Text Available The study on the impacts of human activities on natural resources is of critical importance in constructing effective management strategies in rafting trips. The Camping Schedule Intelligent Generator (CSIG, the computer program developed in the study, which successfully models the complex, dynamic human-environment interactions in the rafting river. This generator includes two parts: artificial intelligence simulation and BSGA-based Optimization. It employs artificial intelligence in creating an individual-based modeling system. With the help of BSGA, this simulation system successfully models the recreatinal rafting behavior and captures the decision making of rafting trips as they responsively seek to optimize their functions. After modeling, the paper applys CSIG to the Colorado River, which is a famous rafting river and find that: the numbers of short motor-trips (6-8 day and long-oar trips (15-18 day are obviously larger than the other two. Finally, the study analyzes the sensitivity of the model and finds that when the water velocity varies in the actual range.

  9. Field and Classroom Strategies for Improving Critical Thinking on Introductory Geoscience Field Trips

    Science.gov (United States)

    Boryta, M. D.; Walker, B.; Long, T.

    2011-12-01

    Although field experiences for introductory geoscience students have tremendous potential with respect to recruiting and retaining majors and enriching their understanding of geologic concepts, implementing field trips that promote critical thinking for introductory students is challenging. After observing that many of our students struggled at applying concepts they learned in the classroom to unfamiliar field areas, we developed teaching strategies and instructional materials for the classroom and the field to promote critical thinking and self-directed learning on field trips. We assessed the effectiveness of these modifications using video, interviews, student field trip reports and field notebooks. Student co-inquirers played a vital role during the project in field instruction and data analysis. We will discuss think-alouds, the importance of repetition in the classroom, allowing adequate processing time, field trip preparation exercises for the classroom, and other significant pedagogical changes that we made. Video of students in the field at the beginning, middle, and end of the project will be shown to illustrate the progressive changes in students' approaches to outcrop analysis over the course of the project.

  10. Recovery from a trip in young and older adults : mechanics and control of the support limb

    NARCIS (Netherlands)

    Pijnappels, M.A.G.M.

    2004-01-01

    Falls and fall-related injuries are the cause of serious medical and social problems, especially in the growing elderly population. Tripping over an obstacle is one of the major causes for falls in the elderly. This thesis was aimed to obtain insight in the requirements for a successful recovery re

  11. How to Make a Field Trip a Hands-On Investigative Laboratory: Learning about Marine Invertebrates

    Science.gov (United States)

    Burrowes, Patricia A.

    2007-01-01

    Research has shown that when students are given the opportunity to ask their own questions and design their own experiments, they become more interested in learning the answers. In this article, the author describes an effective method to do a field trip to the beach and gets her students to make observations about marine animals, come up with a…

  12. Effect of Field Trip On Students’ Academic Performance in Basic Technology in Ilorin Metropolis, Nigeria

    Directory of Open Access Journals (Sweden)

    Abdul Ganiyu Alasela Amosa

    2015-04-01

    Full Text Available The use of field trip in teaching and learning helps to bring about effective and efficient learning in Basic Technology. Field trip is a group excursion away from the normal education environment for firsthand experience of an historic site or place of special interest. This study therefore was geared toward finding out the effect of field trip on students’ academic performance in learning practical skills in Basic Technology in Ilorin, Nigeria. A pre‐test, post‐test and control group quasi‐experimental design was adopted for this study. Two sampled upper basic Schools were selected from Ilorin East Local Government Area of Kwara State using purposive sampling technique. The two sampled upper basic Schools comprised 50 students who were randomly assigned to treatment (25 students and control (25 students groups. Analysis of Co‐variance (ANCOVA was used to analyze the data collected. The findings revealed that at significant level, the value produced F (2, 22 = 3.44 > 0.109 Therefore, hypothesis one was rejected. Also, at 0.05 significant level, the value produced F (2, 9 = 4.26 > 0.433. Therefore, hypothesis two was rejected. Based on the findings, it was recommended among others that; teachers should take students on field trip so as to promote and encourage active engagement in learning, self‐motivation, discovery learning and learning by experience.

  13. An aroid collecting trip to Sarawak and a key to the genera of Araceae in Sarawak

    NARCIS (Netherlands)

    Bogner, J.; Boyce, P.C.

    1995-01-01

    The main aim of the trip was to find an enigmatic aroid that was first collected as a sterile plant by the Australian plant enthusiast Dr. A. Dearden in 1990. The true identity of this Nephthytis-like plant, as we called it in the meantime, remained unclear and we thought that it was probably a new

  14. 75 FR 29678 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Reductions to Trip...

    Science.gov (United States)

    2010-05-27

    ..., continuation of the status quo trip limit will result reaching each of the respective common pool sub-ACLs... Amendment 16 and Framework Adjustment 44 (FW 44) to the NE Multispecies Fishery Management Plan (FMP) and is... under the authority of the Magnuson-Stevens Fishery Conservation and Management Act...

  15. Design and implementation of a genomics field trip program aimed at secondary school students.

    Science.gov (United States)

    McQueen, Jennifer; Wright, Jody J; Fox, Joanne A

    2012-01-01

    With the rapid pace of advancements in biological research brought about by the application of computer science and information technology, we believe the time is right for introducing genomics and bioinformatics tools and concepts to secondary school students. Our approach has been to offer a full-day field trip in our research facility where secondary school students carry out experiments at the laboratory bench and on a laptop computer. This experience offers benefits for students, teachers, and field trip instructors. In delivering a wide variety of science outreach and education programs, we have learned that a number of factors contribute to designing a successful experience for secondary school students. First, it is important to engage students with authentic and fun activities that are linked to real-world applications and/or research questions. Second, connecting with a local high school teacher to pilot programs and linking to curricula taught in secondary schools will enrich the field trip experience. Whether or not programs are linked directly to local teachers, it is important to be flexible and build in mechanisms for collecting feedback in field trip programs. Finally, graduate students can be very powerful mentors for students and should be encouraged to share their enthusiasm for science and to talk about career paths. Our experiences suggest a real need for effective science outreach programs at the secondary school level and that genomics and bioinformatics are ideal areas to explore.

  16. Design and implementation of a genomics field trip program aimed at secondary school students.

    Directory of Open Access Journals (Sweden)

    Jennifer McQueen

    Full Text Available With the rapid pace of advancements in biological research brought about by the application of computer science and information technology, we believe the time is right for introducing genomics and bioinformatics tools and concepts to secondary school students. Our approach has been to offer a full-day field trip in our research facility where secondary school students carry out experiments at the laboratory bench and on a laptop computer. This experience offers benefits for students, teachers, and field trip instructors. In delivering a wide variety of science outreach and education programs, we have learned that a number of factors contribute to designing a successful experience for secondary school students. First, it is important to engage students with authentic and fun activities that are linked to real-world applications and/or research questions. Second, connecting with a local high school teacher to pilot programs and linking to curricula taught in secondary schools will enrich the field trip experience. Whether or not programs are linked directly to local teachers, it is important to be flexible and build in mechanisms for collecting feedback in field trip programs. Finally, graduate students can be very powerful mentors for students and should be encouraged to share their enthusiasm for science and to talk about career paths. Our experiences suggest a real need for effective science outreach programs at the secondary school level and that genomics and bioinformatics are ideal areas to explore.

  17. 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.

  18. 78 FR 54194 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Trip Limit...

    Science.gov (United States)

    2013-09-03

    ... fishing year on July 16, 2013 (77 FR 42478), recent analysis shows that the common pool would likely... National Oceanic and Atmospheric Administration 50 CFR Part 648 RIN 0648-XC823 Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Trip Limit Adjustments for the Common Pool...

  19. 76 FR 53832 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Trip Limit Decrease...

    Science.gov (United States)

    2011-08-30

    ... limit for GOM cod is 500 lb (226.8 kg) per day-at-sea (DAS), up to 2,000 lb (907.2 kg) per trip (76 FR... (76 FR 30035; May 24, 2011). As of August 11, 2011, based on the best available catch information... National Oceanic and Atmospheric Administration 50 CFR Part 648 RIN 0648-XA652 Fisheries of...

  20. A Trip to the Statler Hilton Hotel. The Special Education Curriculum Series.

    Science.gov (United States)

    Kendall, Muriel

    A program designed for high school level work-study classes for students of limited mental ability presents specific curriculum methods and materials to teach information regarding positions available in the hotel industry. A field trip tour of the Boston Statler Hilton Hotel if the focal activity of the unit, and is accompanied by a history of…

  1. Co-Leading Wilderness Trips with a Member of the Opposite Sex.

    Science.gov (United States)

    Millette, Margot; Porter, Tom

    2001-01-01

    A study found that male and female co-leaders of wilderness camping trips were very aware of stereotypes of male and female leadership roles. Sometimes leaders deliberately performed stereotypical tasks and roles of the opposite sex, but tasks and roles generally resulted from preferences, necessity, or participant expectations. The D-R model of…

  2. Management of Official Overseas Trips of Staff in Agri-scientific Research Institutions

    Institute of Scientific and Technical Information of China (English)

    Lizhen; CHEN; Yu; ZHENG; Haiyan; LUO; Qingqun; YAO

    2014-01-01

    Taking Tropical Crops Genetic Resources Institute( TCGRI) of Chinese Academy of Tropical Agricultural Sciences( CATAS) as an example,this paper discussed current situation of management of official overseas trips of staff in agric-scientific research institutions,analyzed existing problems,and finally came up with pertinent recommendations.

  3. Fire and Water Make Steam - Redefining the Role of Competition Law in TRIPS

    DEFF Research Database (Denmark)

    Schovsbo, Jens Hemmingsen

    2011-01-01

    The paper points out the relevance of competition law to international issues of Intellectual Property Law (IPR) and demonstrates how competition law internationally has come to function as an indispensable instrument to balance IPR. The perspective is international and focused on TRIPS. The rule...

  4. Quarry Quest. A Field Trip Guide to the Indiana Limestone District, Monroe and Lawrence Counties, Indiana.

    Science.gov (United States)

    Shewmaker, Sherman N.

    This guide provides information for planning a field trip to the Indiana Limestone District. This district, located in Monroe and Lawrence Counties, Indiana, is responsible for material that has dominated the building-limestone market in the United States for nearly a century. A few of the many well-known buildings using Indiana limestone are the…

  5. Modeling of the Austenite-Martensite Transformation in Stainless and TRIP Steels

    NARCIS (Netherlands)

    Geijselaers, H.J.M.; Hilkhuijsen, P.; Bor, T.C.; Perdahcioglu, E.S.; Boogaard, van den A.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

  6. Effect of Ti additions on micro-alloyed Nb TRIP steel

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jaehyuk; Lee, Seok-Jae; De Cooman, B.C. [Materials Design Laboratory, Graduate Institute of Ferrous Technology, Pohang University of Science and Technology, Pohang (Korea, Republic of); Kim, Sungil [Technical Research Laboratories, POSCO, Gwangyang (Korea, Republic of)

    2011-07-15

    In the present study, the influence of Ti-additions on the mechanical properties of Nb-microalloyed TRIP steel is investigated. Ti micro-alloying additions to multi-phase Nb TRIP steel result in a substantial increase of the yield strength and a reduction of strain hardening. The increase of the yield strength can be attributed mainly to grain refinement with a relatively small contribution of precipitation hardening. Based on general principles and well-known models of alloying strengthening, metallurgical reasons for the observed mechanical behavior of the steel can be formulated. The contribution of precipitation hardening is relatively small as Ti-addition result in the formation of coarse (Nb,Ti)(C,N) particles. The addition of Ti to a Nb-microalloyed TRIP steel leads to a pronounced enhancement of precipitation kinetics of (Nb,Ti)(C,N), thereby increasing their phase fraction. The precipitates coarsen and tend to form groups of aggregates of particles rather than single isolated particles with increasing intercritical annealing time. In addition, Ti-addition to Nb-microalloyed TRIP steel has a direct influence on the chemical composition of the precipitates, which become Ti-rich. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Deepening Students' Scientific Inquiry Skills during a Science Museum Field Trip

    Science.gov (United States)

    Gutwill, Joshua P.; Allen, Sue

    2012-01-01

    Field trips to science museums can provide students with educational experiences, particularly when museum programs emphasize scientific inquiry skill building over content knowledge acquisition. We describe the creation and study of 2 programs designed to significantly enhance students' inquiry skills at any interactive science museum exhibit…

  8. 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.

  9. Taking an Internet Field Trip: Promoting Cultural and Historical Diversity through Mayan Mathematics.

    Science.gov (United States)

    Furner, Joseph; Holbein, Marie F. Doan; Scullion, Karin Jackson

    2000-01-01

    Introduces Internet field trips as a means of instruction for diverse student populations; explores the Mayan mathematics system in an interdisciplinary fourth grade math lesson; suggests strategies for students with limited English proficiency base on TESOL (Teachers of English to Speakers of Other Languages); and includes a sample lesson plan.…

  10. 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.

  11. TripSense: A Trust-Based Vehicular Platoon Crowdsensing Scheme with Privacy Preservation in VANETs.

    Science.gov (United States)

    Hu, Hao; Lu, Rongxing; Huang, Cheng; Zhang, Zonghua

    2016-01-01

    In this paper, we propose a trust-based vehicular platoon crowdsensing scheme, named TripSense, in VANET. The proposed TripSense scheme introduces a trust-based system to evaluate vehicles' sensing abilities and then selects the more capable vehicles in order to improve sensing results accuracy. In addition, the sensing tasks are accomplished by platoon member vehicles and preprocessed by platoon head vehicles before the data are uploaded to server. Hence, it is less time-consuming and more efficient compared with the way where the data are submitted by individual platoon member vehicles. Hence it is more suitable in ephemeral networks like VANET. Moreover, our proposed TripSense scheme integrates unlinkable pseudo-ID techniques to achieve PM vehicle identity privacy, and employs a privacy-preserving sensing vehicle selection scheme without involving the PM vehicle's trust score to keep its location privacy. Detailed security analysis shows that our proposed TripSense scheme not only achieves desirable privacy requirements but also resists against attacks launched by adversaries. In addition, extensive simulations are conducted to show the correctness and effectiveness of our proposed scheme. PMID:27258287

  12. TripSense: A Trust-Based Vehicular Platoon Crowdsensing Scheme with Privacy Preservation in VANETs

    Directory of Open Access Journals (Sweden)

    Hao Hu

    2016-06-01

    Full Text Available In this paper, we propose a trust-based vehicular platoon crowdsensing scheme, named TripSense, in VANET. The proposed TripSense scheme introduces a trust-based system to evaluate vehicles’ sensing abilities and then selects the more capable vehicles in order to improve sensing results accuracy. In addition, the sensing tasks are accomplished by platoon member vehicles and preprocessed by platoon head vehicles before the data are uploaded to server. Hence, it is less time-consuming and more efficient compared with the way where the data are submitted by individual platoon member vehicles. Hence it is more suitable in ephemeral networks like VANET. Moreover, our proposed TripSense scheme integrates unlinkable pseudo-ID techniques to achieve PM vehicle identity privacy, and employs a privacy-preserving sensing vehicle selection scheme without involving the PM vehicle’s trust score to keep its location privacy. Detailed security analysis shows that our proposed TripSense scheme not only achieves desirable privacy requirements but also resists against attacks launched by adversaries. In addition, extensive simulations are conducted to show the correctness and effectiveness of our proposed scheme.

  13. A Provenance-Aware Linked Data Application for Trip Management and Organization

    OpenAIRE

    Garijo Verdejo, Daniel; Villazón-Terrazas, B.; Corcho, Oscar

    2011-01-01

    We present El Viajero, an application1 for exploiting, man- aging and organizing Linked Data in the domain of news and blogs about travelling. El Viajero makes use of several heterogeneous datasets to help users to plan future trips, and relies on the Open Provenance Model2 for modeling the provenance information of the resources.

  14. How does a modal shift from short car trips to cycling affect road safety?

    Science.gov (United States)

    Schepers, J P; Heinen, E

    2013-01-01

    Governments aim to promote a shift from car to bicycle, but concerns about road safety seem to represent an important argument against this encouragement. This study examines the road safety impact of a modal shift from short car trips to cycling in Dutch municipalities. The road safety effect is estimated using Accident Prediction Models (APMs) that account for the non-linearity of risk. APMs are developed utilizing Negative Binomial regression. This study is the first to develop APMs using crash and mobility data from municipalities, and utilizing these models to estimate the effects of changing modal splits of current car and bicycle use to modal splits that actually exist in these municipalities. The results suggest that, under conditions such as in Dutch municipalities, transferring short trips made by cars to bicycles does not change the number of fatalities, but increases the number of serious road injuries. The neutral effect on fatalities, despite the high fatality risk for cyclists, can be explained by there being fewer cars on the road to pose a risk to others, the shorter length of bicycle trips compared to the car trips they replace, and the "safety in numbers" phenomenon. The rise in the number of serious road injuries is due wholly to the high number of cycling crashes with no other vehicle involved. The effect of a modal shift is dependent on the age of the population in which the shift is concentrated, and can be influenced by measures affecting cyclists' injury risk.

  15. SF6断路器中润滑脂过量引起的分解产物分析%Analysis of Decomposition Products by Grease Overdose in SF6 Circuit Breaker

    Institute of Scientific and Technical Information of China (English)

    杨韧; 吴水锋; 汪金星; 菅永峰; 陈江韩; 孙志恒; 修士新

    2013-01-01

    An abnormal level of CO gas was detected in a 126 kV SF6 circuit breaker when it was beingtested.According to the analysis,potential fault has occurred in this circuit breaker.After chemical analysis and experimental research on the source of the CO gas,we disintegrated the circuit breaker in order to check it.Finally we come to conclusion that the fault was caused by the excessive scribbling of lubricating grease.The paper analyses the lubricating grease's influence on the operating characteristics of circuit breaker and the decomposition products of SF6.%对SF6电气设备检测时发现某126 kV断路器CO气体组分体积分数异常,根据分析,该断路器存在潜伏性故障.通过化学分析以及实验研究对可能产生CO的来源进行了分析,并对断路器进行解体检查,最终判断该断路器潜伏性故障产生的原因为润滑脂过量.笔者通过化学反应机理分析了润滑脂涂敷过量对断路器运行特性及SF6气体分解组分的影响.

  16. Approaches to resolving trade disputes.

    Science.gov (United States)

    Wilson, D W; Thiermann, A B

    2003-08-01

    The authors discuss the various approaches to resolving trade disputes available to Member Countries of the OIE (World organisation for animal health). The paper first describes the rights and obligations of Member Countries in setting health measures for the importation of animals and animal products, according to the provisions of the World Trade Organization (WTO) Agreement on the Application of Sanitary and Phytosanitary Measures (the SPS Agreement). The authors indicate how OIE standards may be used to set import measures and introduce issues such as equivalence and the use of provisional measures, which are both areas of potential conflict. The authors then describe the options available for resolving disputes--bilateral discussions, mediation through the OIE, the use of the WTO SPS Committee and the formal WTO dispute settlement process, discussing the advantages and disadvantages of each. PMID:15884603

  17. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October - December 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  18. Time-resolved molecular imaging

    Science.gov (United States)

    Xu, Junliang; Blaga, Cosmin I.; Agostini, Pierre; DiMauro, Louis F.

    2016-06-01

    Time-resolved molecular imaging is a frontier of ultrafast optical science and physical chemistry. In this article, we review present and future key spectroscopic and microscopic techniques for ultrafast imaging of molecular dynamics and show their differences and connections. The advent of femtosecond lasers and free electron x-ray lasers bring us closer to this goal, which eventually will extend our knowledge about molecular dynamics to the attosecond time domain.

  19. Resolved observations of transition disks

    CERN Document Server

    Casassus, Simon

    2016-01-01

    Resolved observations are bringing new constraints on the origin of radial gaps in protoplanetary disks. The kinematics, sampled in detail in one case-study, are indicative of non-Keplerian flows, corresponding to warped structures and accretion which may both play a role in the development of cavities. Disk asymmetries seen in the radio continuum are being interpreted in the context of dust segregation via aerodynamic trapping. We summarise recent observational progress, and also describe prospects for improvements in the near term.

  20. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July - September 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  1. Spectrally resolved fluorescent lifetime imaging

    OpenAIRE

    Hanley, Quentin S.

    2008-01-01

    Placing an imaging spectrograph or related components capable of generating a spectrum between a microscope and the image intensifier of a conventional fluorescence lifetime imaging (FLIM) system creates a spectrally resolved FLIM (SFLIM). This arrangement provides a number of opportunities not readily available to conventional systems using bandpass filters. The examples include: simultaneous viewing of multiple fluorophores; tracking of both the donor and acceptor; and observation of a rang...

  2. 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.

  3. With the help of a foreign ally: biopharmaceutical innovation in India after TRIPS.

    Science.gov (United States)

    Angeli, Federica

    2014-05-01

    This article investigates the implications of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS), which reached full-fledged implementation in 2005, for the patenting activity of Indian biopharmaceutical companies. The Indian biopharmaceutical industry is well-known for its generic producers, whose business models capitalize on the opportunity to reverse-engineer patented compounds and produce them at low costs through process innovation. By strengthening intellectual property rights, TRIPS determined a major regulative change, which presents the characteristics of an institutional shock. The examination of the patenting and alliance activity of 123 Indian biopharmaceutical firms between 1999 and 2009 reveals two important insights. First, the innovation outcome of Indian biopharmaceuticals has sharply increased during the transition to TRIPS-compliant regulation, suggesting that Indian companies have been capable and willing to transit from an imitation-based to an innovation-based business model. Second, those biopharmaceutical firms holding cross-border alliances to foreign partners have proved significantly more successful at enhancing their innovative capability. This research delivers a multifold contribution to the policy debate surrounding the enforcement of TRIPS in emerging economies. First, it suggests that such regulatory change may have encouraged biopharmaceutical innovation in India, despite the sceptical voices who did not foresee any benefits because of inherent inertia of the industry. Second, by arguing and testing the advantages of foreign partnerships, this research highlights that the much feared return of pharmaceutical foreign companies to India could instead favour adaptation to institutional change. Implications for Indian public health are particularly critical. The impact of TRIPS on drug pricing and on the capability--and willingness--of Indian biopharmaceuticals to invest in local health conditions are two

  4. Clinical and immunological effects of a forest trip in children with asthma and atopic dermatitis.

    Directory of Open Access Journals (Sweden)

    Sung Chul Seo

    2015-02-01

    Full Text Available Asthma and atopic dermatitis are common allergic diseases, and their prevalence has increased in urban children. Recently, it is becoming understood that forest environment has favorable health effects in patients with chronic diseases. To investigate favorable clinical and immunologic effects of forest, we examined changes in clinical symptoms, indirect airway inflammatory marker, and serum chemokines before and after a short-term forest trip. The forest trips were performed with 21 children with asthma and 27 children with atopic dermatitis. All participating children were living in air polluted urban inner-city. We measured spirometry and fractional exhaled nitric oxide (FeNO in children with asthma and measured scoring atopic dermatitis (SCORAD index and Thymus and Activation-Regulated Chemokine (TARC/CCL17 and Macrophage-Derived Chemokine (MDC/CCL22 levels in children with atopic dermatitis before and after the forest trip. Indoor air pollutants such as indoor mold, particulate matter 10 (PM10 and total volatile organic compounds (TVOCs of each child's home and the accommodations within forest were measured. A significant increase in forced vital capacity (FVC and a significant decrease in FeNO were observed after the forest trip in children with asthma. SCORAD indices and MDC/CCL22 levels were significantly decreased after the forest trip in children with atopic dermatitis. Airborne mold and PM10 levels in indoor were significantly lower in the forest accommodations than those of children's homes; however, TVOC levels were not different between the two measured sites. Short-term exposure to forest environment may have clinical and immunological effects in children with allergic diseases who were living in the urban community.

  5. 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.

  6. Impact of travel mode shift and trip distance on active and non-active transportation in the São Paulo Metropolitan Area in Brazil

    Directory of Open Access Journals (Sweden)

    Thiago Hérick de Sá

    2015-01-01

    Conclusion: Transport and urban planning policies to reduce individual motorized trips and the number of long trips might produce important health benefits, both by increasing population levels of active transportation and reducing the non-active and the total time of daily trips.

  7. Filter cake breaker systems

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Marcelo H.F. [Poland Quimica Ltda., Duque de Caxias, RJ (Brazil)

    2004-07-01

    Drilling fluids filter cakes are based on a combination of properly graded dispersed particles and polysaccharide polymers. High efficiency filter cakes are formed by these combination , and their formation on wellbore walls during the drilling process has, among other roles, the task of protecting the formation from instantaneous or accumulative invasion of drilling fluid filtrate, granting stability to well and production zones. Filter cake minimizes contact between drilling fluid filtrate and water, hydrocarbons and clay existent in formations. The uniform removal of the filter cake from the entire interval is a critical factor of the completion process. The main methods used to breaking filter cake are classified into two groups, external or internal, according to their removal mechanism. The aim of this work is the presentation of these mechanisms as well their efficiency. (author)

  8. Bayes Ice-Breaker

    Science.gov (United States)

    Jessop, Alan

    2010-01-01

    Showing simply how statistical thinking can help in weighing evidence and reaching decisions can be useful both as an introduction to an extended presentation of statistical theory and as an introduction to a looser discussion of the nature and value of data.

  9. Beijing Back Breakers

    Institute of Scientific and Technical Information of China (English)

    MICHAEL; L.; O’NEAL

    2010-01-01

    When I first arrived here a few months ago, I couldn’t help but notice several work projects going on all around me. A new dorm was being built on campus where I would be teaching, as well as a courtyard being repaved and bricked in front of the female students’ dormitory, and a building next to my gym was being renovated.

  10. Beijing Back Breakers

    Institute of Scientific and Technical Information of China (English)

    MICHAEL L. O'NEAL

    2010-01-01

    @@ When I first arrived here a few months ago, I couldn't help but notice several work projects going on all around me. A new dorm was being built on campus where I would be teach-ing, as well as a courtyard being repaved and bricked in front of the female students' dormitory, and a building next to my gym was being renovated. I wondered how long it would take to finish these large tasks, espe-cially the courtyard, as school would begin in about a week, and it would be a mess for students to have to walk through mud, over piles of sand, and around stacks of bricks to get where they wanted to go.

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

    Science.gov (United States)

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

    2014-03-01

    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.

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

    International Nuclear Information System (INIS)

    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.

  13. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1990) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  14. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  15. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  16. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April-June 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  17. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  18. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April--June 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  19. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  20. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1990) and includes copies of letters, notices, and orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication