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Sample records for instantaneous blockage accident

  1. Radionuclide Release after Channel Flow Blockage Accident in CANDU-6 Plant

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hoon; Jun, Hwang Yong [Korea Electric Power Corporation Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    The channel flow blockage accident is one of the in core loss of coolant accidents, the release path of radionuclide is very different from conventional loss of coolant accidents. The large amount of radionuclide released from broken channel is being washed during it passes through the moderator in Calandria. The objective of containment behavior analysis for channel flow blockage event is to assess the amount of radionuclide release to the ambient atmosphere. Radionuclide release rates in case of channel flow blockage with all safety system available, that is containment building is intact, as well as with containment system impairment are analyzed with GOTHIC and SMART code

  2. A new CFD modeling method for flow blockage accident investigations

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Wenyuan, E-mail: fanwy@mail.ustc.edu.cn; Peng, Changhong, E-mail: pengch@ustc.edu.cn; Chen, Yangli, E-mail: chenyl@mail.ustc.edu.cn; Guo, Yun, E-mail: guoyun79@ustc.edu.cn

    2016-07-15

    Highlights: • Porous-jump treatment is applied to CFD simulation on flow blockages. • Porous-jump treatment predicts consistent results with direct CFD treatment. • Relap5 predicts abnormal flow rate profiles in MTR SFA blockage scenario. • Relap5 fails to simulate annular heat flux in blockage case of annular assembly. • Porous-jump treatment provides reasonable and generalized CFD results. - Abstract: Inlet flow blockages in both flat and annular plate-type fuel assemblies are simulated by (Computational Fluid Dynamics) CFD and system analysis methods, with blockage ratio ranging from 60 to 90%. For all the blockage scenarios, mass flow rate of the blocked channel drops dramatically as blockage ratio increases, while mass flow rates of non-blocked channels are almost steady. As a result of over-simplifications, the system code fails to capture details of mass flow rate profiles of non-blocked channels and power redistribution of fuel plates. In order to acquire generalized CFD results, a new blockage modeling method is developed by using the porous-jump condition. For comparisons, direct CFD simulations are conducted toward postulated blockages. For the porous-jump treatment, conservative flow and heat transfer conditions are predicted for the blocked channel, while consistent predictions are obtained for non-blocked channels. Besides, flow fields in the blocked channel, asymmetric power redistributions of fuel plates, and complex heat transfer phenomena in annular fuel assembly are obtained and discussed. The present study indicates that the porous-jump condition is a reasonable blockage modeling method, which predicts generalized CFD results for flow blockages.

  3. Physico-statistical approach to assess the core damage variability due to a total instantaneous blockage of SFR fuel sub-assembly

    Energy Technology Data Exchange (ETDEWEB)

    Marie, N., E-mail: nathalie.marie@cea.fr [CEA, DEN, DER, Saint Paul Lez Durance, F-13108 (France); Marrel, A. [CEA, DEN, DER, Saint Paul Lez Durance, F-13108 (France); Seiler, J.M. [CEA, DEN, DTN, Grenoble, F-38054 (France); Bertrand, F. [CEA, DEN, DER, Saint Paul Lez Durance, F-13108 (France)

    2016-02-15

    Highlights: • Physico-statistical tool for SFR safety for Total Instantaneous Blockage accident. • 0D/1D but realistic physical models to describe the phenomenological event tree. • Twenty-seven uncertain parameters identified to cover all realistic accidental transients. • Uncertainty propagation performed via a Monte-Carlo sampling. • Quantification of safety margins: 18.1% of cases above the safety criterion. - Abstract: Within the framework of the generation IV Sodium Fast Reactors (SFR) R&D program of CEA (French commissariat à l’énergie atomique et aux énergies alternatives), the safety in case of accidents is assessed. These accidental scenarios involve very complex transient phenomena. To get round the difficulty of modelling them, only ‘Bounding’ (most damaging) accidental conditions have been up to now studied for the safety demonstration. These transients are simulated with very complex multi-physical codes (such as SIMMER) which nevertheless include some adjusted and not well known parameters and require a long CPU (process) time preventing their direct use for uncertainty propagation and sensitivity studies, especially in case of a high number of uncertain input parameters. To cope with these constraints, a new physico-statistical approach is followed in parallel by the CEA. This approach involves the fast-running description of extended accident sequences coupling analytical models for the main physical phenomena in combination with advanced statistical analysis techniques. The efficiency of the methodology for the reactor safety analysis is demonstrated here for one type of accident – the Total Instantaneous Blockage (TIB) – which involves an extended range of complex physical phenomena. From the establishment of the physical models describing the TIB phenomenology, 27 uncertain input parameters and their associated probability distributions are identified. A propagation of these input parameter uncertainties is performed via a

  4. CFD Investigation for Flow Blockage Accident in a Lower Plenum

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, J.; Chang, W. P.; Jeong, J. H.; Ha, K. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Large Partial Inlet flow blockage is involved as a BE (Bounding Event) in PGSFR. There are no known sources for objects of this nature in the inlet plenum but one could postulate that a large object might be gotten down to lower plenum. It is possible to block the entrance of nozzle at receptacle which has 6 nozzles located just below the orifice plates. Then it can cause the flow reduction that flows into a fuel assembly and affect cladding integrity. The objective of the present study is to predict the flow reduction of hottest assembly as well as flow features in a lower plenum when orifice nozzle under hottest assembly is blocked by large objects. A CFD analysis by fully resolved RANS simulations has been carried out to predict effects of flow blockage at side orifice as well as flow feature in a lower plenum. In the no-blockage case, the velocity vector around the side orifice nozzle has symmetry because flow is uniformly distributed through 6-side orifice nozzle. The velocity of flow right after passing through orifice nozzle increases very rapidly which is estimated as maximum 7.5 m/s and pressure drops abruptly. This is the conversion of potential energy to kinetic energy in compliance with the Bernoulli's theorem. For 5-orifce nozzle blockage cases, recirculation around the side orifice nozzle was found, which is asymmetric and complex. This means that reduced flow area had a more influence on friction loss by viscosity and it occurred more flow resistance compared to no-blockage case. The maximum velocity for the 5-orifice nozzle blockage case was estimated as 13 m/s The more blockage area at orifice increases, the more flow rate of the hottest assembly decreases. The maximum reduced flow of hottest assembly was predicted to be about 9.32 kg/s.

  5. Modeling and Simulation of Release of Radiation in Flow Blockage Accident for Two Loops PWR

    OpenAIRE

    Khurram Mehboob; Cao Xinrong; Majid Ali

    2012-01-01

    In this study modeling and simulation of release of radiation form two loops PWR has been carried out for flow blockage accident. For this purpose, a MATLAB based program “Source Term Evaluator for Flow Blockage Accident” (STEFBA) has been developed, which uses the core inventory as its primary input. The TMI-2 reactor is considered as the reference plant for this study. For 1100 reactor operation days, the core inventory has been evaluated under the core design constrains at average reactor ...

  6. CFD study on inlet flow blockage accidents in rectangular fuel assembly

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Wenyuan, E-mail: fanwy@mail.ustc.edu.cn; Peng, Changhong, E-mail: pengch@ustc.edu.cn; Guo, Yun, E-mail: guoyun79@ustc.edu.cn

    2015-10-15

    Highlights: • 3D CFD and Relap5 simulations on inlet flow blockage are performed. • Transient effects are investigated by dynamic mesh technique. • Similar flow and power redistributions are predicted in both methods. • Local effects of the blockage are captured by CFD method and analyzed. - Abstract: Three-dimensional transient CFD simulation of 90% inlet flow blockage accidents in rectangular fuel assembly is performed, using the dynamic mesh technique. One-dimensional steady calculation is done for comparison, using Relap5 code. Similar mass flow rate redistributions and asymmetric power redistributions of the plate in the blocked scenario are obtained. No boiling is predicted in both simulations, however, CFD approach provides more in-depth investigations of flow transients and the thermal-hydraulic interaction. The development of flow blockage transients is so fast that the rapid redistribution of mass flow rates occurs in only 0.015 s after the formation of the blockage. As a sequence of the inlet flow blockage, jet-flows and reversed flows occur in the blocked channel. This leads to complex temperature distributions of coolants and fuel plates, in which, the highest coolant temperature no longer occurs around the channel outlet. The present study shows the advantage and significance of the application of three-dimensional transient CFD technique in investigating flow blockage accidents.

  7. A probability risk assessment for MACSTOR/KN-400 during an air inlet blockage accident sequence

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, J.H.; Jae, M. [Hanyang Univ., Dept. of Nuclear Engineering, Sungdong-Gu, Seoul (Korea, Republic of); Jeong, C. [Korea Inst. of Nuclear Safety, Yusong-Gu, Taejon (Korea, Republic of)

    2006-07-01

    The safety assessment framework for evaluating the spent fuel dry storage facility during the air inlet blockage accident composing of three phases has been established and applied to an interim storage system. They include the analysis of the failure probability of a basket and a cylinder, the accident modeling of spent fuel dry storage facility and the accident consequence assessments. The first phase of the analysis calculated the module failure probability by modeling of the basket and the cylinder, which is major element for containing radioactive substances. The second phase includes a modeling of spent fuel dry storage facility. At this phase, the probability that radioactive substances are released to outside when the initial event happens has been calculated by the construction of the event tree methods against a various elements which affects the air inlet blockage accident. At the third phase of releasing radioactive substances, the radiation damage to affect neighborhood and storage facility worker using MACCS2 code has been evaluated quantitatively. (author)

  8. Two-lane traffic simulations with a blockage induced by an accident car

    Science.gov (United States)

    Zhu, H. B.; Lei, L.; Dai, S. Q.

    2009-07-01

    Based on the two-lane traffic model proposed by Chowdhury et al., a highway traffic model with a blockage induced by an accident car is proposed, in which both symmetric lane changing rules and asymmetric lane changing rules are adopted. The fundamental diagrams and spatial-temporal profiles are presented after the numerical simulation and the jam transition is studied. It is shown that the accident car not only causes a local jam behind the accident car, but also causes vehicles to cluster in the bypass lane. The asymmetric lane changing rules are more advantageous in reducing the local jam than the symmetric lane changing rules when the accident car is in the right lane, and the symmetric lane changing rules are superior when the accident car is in the left lane. Furthermore the curves of lane-changing frequency against the total density are given. It is found that the vehicles will change lane more frequently when traffic is inhomogeneous with different types of vehicle or with an accident car.

  9. Cumulative Damage Fraction Evaluation for the Sub-channel Blockage Accident in PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jin; Chang, Won-Pyo; Ha, Ki-Suk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    In determining a safety concern of sub-assembly, the CDF or life fraction, is very useful for predicting pins failure within sub-assembly that are subjected to creep damage at elevated temperatures and has been accepted as a means for predicting fuel pin failure in SFR. In particular, the sub-channels inside a fuel assembly in Sodium cooled Fast Reactor (SFR) may partially be blocked by an ingression of damaged fuel debris or foreign obstacles into fuel assembly due to the geometrically compact design of the core fuel pin arrangement. When the partial blockage occurs, sodium coolant flow would be disturbed in the vicinity of the blockage, and the affected flow could lead to a high local coolant temperature. The cladding breaching is assumed to occur when the CDF exceeds 1.0 and it is required that the CDF be below 1.0 to avoid the creep rupture of the cladding tube in fuel pin design. It is, therefore, important to evaluate the CDF of the fuel pins in an assembly of the 150MWe Prototype SFR. The objective of this paper is to predict the CDF of fuel pin within the hottest assembly which is designed in KAERI when the sub-channel blockage accident occurs. For the preliminary analysis, the CDF was calculated in the nominal condition without the hot channel factor. The evaluation of cumulative damage fraction was carried out for 6 sub-channel blockages in 150MWe Prototype Sodium cooled Fast Reactor (PGSFR) using the MATRA-LMR-FB code. The fuel peak temperature of the hottest pin was about 605 .deg. C and the CDF value obtained from the hottest pin during 1160 effective full power days (EFPDs) is 0.006, which means that fuel pins have large safety margins against breaching.

  10. A probability risk assessment for MACSTOR/KN-400 during the air inlet blockage accident

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jung Hyun; Jae, Moo Sung [Hanyang University, Seoul (Korea, Republic of); Jeong, Chan Woo [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)

    2004-07-01

    Spent fuels extracted from a reactor can be reused or be deposited to all eternity. Before they are chosen between these two ways, spent fuels are stored in the intermediate storage. The spent fuel dry storage facility is an intermediate storage using air-cooling method. In Korea, because of the current situation, spent fuels derived from continuous operation of PHWRs cannot be stored in a pool, spent fuel dry storage facility is scheduled to be built by year 2016. Therefore, the use of PSA technology for designing spent fuel intermediate storage facility needs to be developed. In this study, the safety analysis for the sequence of air inlet blockage accident in spent fuel dry storage facility is analyzed.

  11. Car accidents and number of stopped cars due to road blockage on a one-lane highway

    Science.gov (United States)

    Boccara, N.; Fuks, H.; Zeng, Q.

    1997-05-01

    Within the framework of a simple model of car traffic on a one-lane highway, we study the probability of the occurrence of car accidents when drivers do not respect the safety distance between cars, and, as a result of the blockage during the time T necessary to clear the road, we determine the number of stopped cars as a function of car density. We give a simple theory in good agreement with our numerical simulations.

  12. Car accidents and number of stopped cars due to road blockage on a one-lane highway

    CERN Document Server

    Boccara, N; Zeng, Q

    1997-01-01

    Within the framework of a simple model of car traffic on a one-lane highway, we study the probability for car accidents to occur when drivers do not respect the safety distance between cars, and, as a result of the blockage during the time $T$ necessary to clear the road, we determine the number of stopped cars as a function of car density. We give a simple theory in good agreement with our numerical simulations.

  13. Subchannel analysis with flow blockages

    Science.gov (United States)

    Sabotinov, L.

    1985-05-01

    The steady state single-phase three-dimensional flow in the rod bundle geometry of a nuclear pressurized water reactor was calculated with the PHOENICS 84 program. Flow blockages, which may occur under accident conditions, are simulated. Results show that PHOENICS-84 can be applied to calculation of the three-dimensional fields of velocities in fuel rod bundles containing complete flow blockages in cells. The code can treat recirculation zones.

  14. Analysis and Discussion of Cold Box Frozen-Blockage Accident of Liquid Nitrogen Wash Unit%液氮洗装置冷箱冻堵事故分析与讨论

    Institute of Scientific and Technical Information of China (English)

    贾震宇

    2014-01-01

    An introduction is given of the background and process of a typical cold box frozen-blockage accident caused by water inflow of liquid nitrogen wash unit , and causes for the accident are analyzed .In connection with the accident , relevant process recovery method is proposed , and effective control measures are taken to prevent such an accident from happening again .%介绍了一起典型的液氮洗装置进水导致冷箱冻堵事故的背景及经过,分析了导致事故的原因。针对事故原因,提出了相应的工艺恢复方法,并通过制定有效的控制手段来避免此类事故的再次发生。

  15. Modeling and analysis framework for core damage propagation during flow-blockage-initiated accidents in the Advanced Neutron Source Reactor at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.H.; Taleyarkhan, R.P.; Navarro-Valenti, S.; Georgevich, V.

    1995-09-01

    This paper describes modeling and analysis to evaluate the extent of core damage during flow blockage events in the Advanced Neutron Source (ANS) reactor planned to be built at the Oak Ridge National Laboratory (ORNL). Damage propagation is postulated to occur from thermal conduction between damaged and undamaged plates due to direct thermal contact. Such direct thermal contact may occur because of fuel plate swelling during fission product vapor release or plate buckling. Complex phenomena of damage propagation were modeled using a one-dimensional heat transfer model. A scoping study was conducted to learn what parameters are important for core damage propagation, and to obtain initial estimates of core melt mass for addressing recriticality and steam explosion events. The study included investigating the effects of the plate contact area, the convective heat transfer coefficient, thermal conductivity upon fuel swelling, and the initial temperature of the plate being contacted by the damaged plate. Also, the side support plates were modeled to account for their effects on damage propagation. The results provide useful insights into how various uncertain parameters affect damage propagation.

  16. CHEMICAL EFFECTS ON PWR SUMP STRAINER BLOCKAGE AFTER A LOSS-OF-COOLANT ACCIDENT: REVIEW ON U.S. RESEARCH EFFORTS

    Directory of Open Access Journals (Sweden)

    CHI BUM BAHN

    2013-06-01

    Full Text Available Industry- or regulatory-sponsored research activities on the resolution of Generic Safety Issue (GSI-191 were reviewed, especially on the chemical effects. Potential chemical effects on the head loss across the debris-loaded sump strainer under a post-accident condition were experimentally evidenced by small-scale bench tests, integrated chemical effects test (ICET, and vertical loop head loss tests. Three main chemical precipitates were identified by WCAP-16530-NP: calcium phosphate, aluminum oxyhydroxide, and sodium aluminum silicate. The former two precipitates were also identified as major chemical precipitates by the ICETs. The assumption that all released calcium would form precipitates is reasonable. CalSil insulation needs to be minimized especially in a plant using trisodium phosphate buffer. The assumption that all released aluminum would form precipitates appears highly conservative because ICETs and other studies suggest substantial solubility of aluminum at high temperature and inhibition of aluminum corrosion by silicate or phosphate. The industry-proposed chemical surrogates are quite effective in increasing the head loss across the debris-loaded bed and more effective than the prototypical aluminum hydroxide precipitates generated by in-situ aluminum corrosion. There appears to be some unresolved potential issues related to GSI-191 chemical effects as identified in NUREG/CR-6988. The United States Nuclear Regulatory Commission, however, concluded that the implications of these issues are either not generically significant or are appropriately addressed, although several issues associated with downstream in-vessel effects remain.

  17. Safety Analysis for Sub-channel Blockage in the PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jin; Chang, Wonpyo; Ha, Kisuk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The flow perturbation caused by the blockage could raise the local coolant temperature in the incident and it might eventually lead to the degradation of the fuel rods. Therefore, a partial flow blockage accident must be a safety concern in the SFR design. In this regard, analyses were performed for the flow blockage accident postulated in a conceptual design of a 150MWe Proto-type SFR using the MATRA-LMR/FB and analysis result was compared to the safety acceptance criterion shown in Table 1 developed by KAERI. The maximum coolant temperatures for 6, 24 channels blockage occurred at the end of the fuel slug and both of them satisfied the safety limits. However, for the 54 channels blockage, the maximum coolant temperature was found in the downstream of the blockage and it could not meet the safety limits. It was caused by the recirculation region in the downstream of the blockage. In conclusion, satisfactory margins were obtained for 6, 24 channel blockage cases.

  18. Safety analysis on large partial inlet flow blockage in PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, J.; Chang, W. P.; Jeong, J. H.; Ha, K. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The objective of the present study is to predict cladding temperature for the hot assembly by postulating flow blockage accident occurring side orifice nozzles at lower plenum. The large partial inlet flow blockage occurring orifice nozzles of receptacle was estimated by MATRA-LMR/FB. It is hypothesized that a large object has gotten down to lower plenum during normal operation and blocked side orifice nozzles at lower plenum. The flow blockage has been considered one of the main issues to be addressed in SFR since the Ferim-1 suffered a partial fuel meltdown. The flow blockage causes an insufficient amount of coolant to enter the fuel assembly. Large Partial Inlet flow blockage is classified as DEC (Design Extension Condition) for PGSFR. There are several flow paths at lower plenum and possibility of occurrence of inlet flow blockage is estimated to be about 1 x 10{sup -8} which is very remote. However, it should be dealt with in PGSFR because it is a BE (Bounding Event). There are no known sources for inlet flow blockage but one could postulate that a large object might be gotten down to lower plenum during normal operation. Then it leads to not only reduced flow rate that flows into assemblies but also temperature increase within fuel assembly. The results indicate that 3-orifice nozzles blockage (50% of blockage area) lead to a maximum clad temperature of inner/outer core assembly around 670 .deg. C/580 .deg. C. This is guaranteed that safety margin is enough considering the eutectic temperature. On the other hand, for more than 4-orifice nozzles blockage (67% of blockage area), the maximum clad temperature of both inner/outer core assembly reaches around 806 .deg. C/739 .deg. C, respectively, which go beyond eutectic temperature.

  19. In-situ Blockage Monitoring of Sensing Line

    Directory of Open Access Journals (Sweden)

    Aijaz Ahmed Mangi

    2016-02-01

    Full Text Available A reactor vessel level monitoring system measures the water level in a reactor during normal operation and abnormal conditions. A drop in the water level can expose nuclear fuel, which may lead to fuel meltdown and radiation spread in accident conditions. A level monitoring system mainly consists of a sensing line and pressure transmitter. Over a period of time boron sediments or other impurities can clog the line which may degrade the accuracy of the monitoring system. The aim of this study is to determine blockage in a sensing line using the energy of the composite signal. An equivalent Pi circuit model is used to simulate blockages in the sensing line and the system's response is examined under different blockage levels. Composite signals obtained from the model and plant's unblocked and blocked channels are decomposed into six levels of details and approximations using a wavelet filter bank. The percentage of energy is calculated at each level for approximations. It is observed that the percentage of energy reduces as the blockage level in the sensing line increases. The results of the model and operational data are well correlated. Thus, in our opinion variation in the energy levels of approximations can be used as an index to determine the presence and degree of blockage in a sensing line.

  20. Research on Precaution and Detection Technology for Flow Blockage of Plate-type Fuel Element in Research Reactors

    Institute of Scientific and Technical Information of China (English)

    DING; Li; QIAO; Ya-xin; ZHANG; Nian-peng; LUO; Bei-bei; HUA; Xiao; JIA; Shu-jie; YAN; Hui-yang

    2013-01-01

    The main aim of this study is to offer the technical support for safety operation and management of research reactors using plate-type fuel assemblies in China,which is performed from analysis of precaution measures for flow blockage and detection methods of accidents.Study shows that most accidents were induced by in-core foreign objects and the swelling of fuel

  1. Transient wave-blockage interaction and extended blockage detection in elastic water pipelines

    Science.gov (United States)

    Duan, H. F.; Lee, P. J.; Ghidaoui, M. S.; Tuck, J.

    2014-04-01

    Extended partial blockages are common in pressurized water pipelines and can result in the wastage of energy, the reduction in system carrying capacity and the increased potential for contamination. This paper investigates the transient wave-blockage interaction and its application to extended blockage detection in pipelines, where blockage-induced changes to the system resonant frequencies are observed. The frequency shifting is first inspected and explained in this study through wave perturbation analysis, providing a theoretical confirmation for the result that unlike discrete blockages, extended blockages cause resonant frequency shifts in the system. Furthermore, an analytical expression is derived for the relationship between the blockage properties and the resonant frequency shifts and is used to detect the blockages in this study. The obtained results are validated through both numerical applications and laboratory experiments, where the accuracy and efficiency of the developed method for extended blockage detection are tested.

  2. Instantaneous stochastic perturbation theory

    CERN Document Server

    Lüscher, Martin

    2015-01-01

    A form of stochastic perturbation theory is described, where the representative stochastic fields are generated instantaneously rather than through a Markov process. The correctness of the procedure is established to all orders of the expansion and for a wide class of field theories that includes all common formulations of lattice QCD.

  3. Analysis of partial and total flow blockage of a single fuel assembly of an MTR research reactor core

    Energy Technology Data Exchange (ETDEWEB)

    Adorni, Martina [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Facolta di Ingegneria, Universita di Pisa, Via Diotisalvi, 2-56100 Pisa (Italy)]. E-mail: martina_adorni@tin.it; Bousbia-Salah, Anis [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Facolta di Ingegneria, Universita di Pisa, Via Diotisalvi, 2-56100 Pisa (Italy); Hamidouche, Tewfik [Commissariat a l' Energie Atomique, Centre de Recherche Nucleaire d' Alger-Algeria, 02 Boulevard Frantz fanon, BP 399 Alger-gare (Algeria); Maro, Beniamino Di [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Facolta di Ingegneria, Universita di Pisa, Via Diotisalvi, 2-56100 Pisa (Italy); Pierro, Franco [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Facolta di Ingegneria, Universita di Pisa, Via Diotisalvi, 2-56100 Pisa (Italy); D' Auria, Francesco [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Facolta di Ingegneria, Universita di Pisa, Via Diotisalvi, 2-56100 Pisa (Italy)

    2005-10-15

    The main aim of the following study is to perform a safety analysis of the IAEA 10 MW MTR Pool type Research Reactor [IAEA-TECDOC-233, 1980. IAEA Research Reactor Core Conversion from the use of high-enriched uranium to the use of low enriched uranium fuels Guidebook] under flow blockage of a single Fuel Assembly (FA) conditions. Such event was rarely investigated in the open literature notwithstanding the fat that it constitutes a severe accident that may lead to local dryout and eventually to loss of the FA integrity. The transients herein considered are related to partial and total obstruction of the cooling channel of a single Fuel Assembly of the reactor core. This study constitutes the first step of a larger work, which consists in performing a 3D simulation using the Best Estimate coupled code technique. However, as a first approach the instantaneous reactor power is derived through the point kinetic approach of the used thermal-hydraulic system code.

  4. Effects of sleeve blockages on axial velocity and intensity of turbulence in an unheated 7 x 7 rod bundle. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    Creer, J.M.; Rowe, D.S.; Bates, J.M.; Sutey, A.M.

    1976-01-01

    An experimental study is described which was performed to investigate the turbulent flow phenomena near postulated sleeve blockages in a model nuclear fuel rod bundle. The sleeve blockages were characteristic of fuel clad ''swelling'' or ''ballooning'' which could occur during loss-of-coolant accidents (LOCA) in pressurized water reactors. The study was conducted to provide information relative to the flow phenomena near postulated blockages to support detailed safety analyses of LOCAs. The results of the study are especially useful for verification of the hydraulic treatment of reactor core computer programs such as COBRA.

  5. ISAR imaging using the instantaneous range instantaneous Doppler method

    CSIR Research Space (South Africa)

    Wazna, TM

    2015-10-01

    Full Text Available In Inverse Synthetic Aperture Radar (ISAR) imaging, the Range Instantaneous Doppler (RID) method is used to compensate for the nonuniform rotational motion of the target that degrades the Doppler resolution of the ISAR image. The Instantaneous Range...

  6. Instantaneous Frequency Attribute Comparison

    Science.gov (United States)

    Yedlin, M. J.; Margrave, G. F.; Ben Horin, Y.

    2013-12-01

    The instantaneous seismic data attribute provides a different means of seismic interpretation, for all types of seismic data. It first came to the fore in exploration seismology in the classic paper of Taner et al (1979), entitled " Complex seismic trace analysis". Subsequently a vast literature has been accumulated on the subject, which has been given an excellent review by Barnes (1992). In this research we will compare two different methods of computation of the instantaneous frequency. The first method is based on the original idea of Taner et al (1979) and utilizes the derivative of the instantaneous phase of the analytic signal. The second method is based on the computation of the power centroid of the time-frequency spectrum, obtained using either the Gabor Transform as computed by Margrave et al (2011) or the Stockwell Transform as described by Stockwell et al (1996). We will apply both methods to exploration seismic data and the DPRK events recorded in 2006 and 2013. In applying the classical analytic signal technique, which is known to be unstable, due to the division of the square of the envelope, we will incorporate the stabilization and smoothing method proposed in the two paper of Fomel (2007). This method employs linear inverse theory regularization coupled with the application of an appropriate data smoother. The centroid method application is straightforward and is based on the very complete theoretical analysis provided in elegant fashion by Cohen (1995). While the results of the two methods are very similar, noticeable differences are seen at the data edges. This is most likely due to the edge effects of the smoothing operator in the Fomel method, which is more computationally intensive, when an optimal search of the regularization parameter is done. An advantage of the centroid method is the intrinsic smoothing of the data, which is inherent in the sliding window application used in all Short-Time Fourier Transform methods. The Fomel technique

  7. Accidents - Chernobyl accident; Accidents - accident de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

  8. The strainer blockage assessment methodology used

    Energy Technology Data Exchange (ETDEWEB)

    Zigler, G.L.; Rao, D.V. [Science and Engineering Associates, Inc., Albuquerque, NM (United States)

    1996-03-01

    On July 28, 1992 a spurious opening of a safety valve at Barseback Unit 2 in Sweden resulted in clogging of the Containment Vessel Spray System strainers in less than one hour. Instances of ECCS strainer clogging have occurred in U.S. BWRs. Given these precursors the USNRC staff initiated analyses to estimate the potential for loss of NPSH of the ECCS pumps in BWRs due to clogging of suction strainers by a combination of fibrous and particulate material. The BLOCKAGE code was developed in support of NUREG/CR-6224, a probabilistic scoping analysis of a BWR/4 with a Mark 1 containment. This paper addresses the key elements of the methodology used in the BLOCKAGE code to assess head loss across ECCS strainers. The debris generation model, the debris drywell transport, and the suppression pool models are discussed briefly. NUREG/CR-6224 provides in-depth discussions of the models used in BLOCKAGE. Additionally, user interface features of BLOCKAGE are discussed.

  9. Novel instantaneous laser Doppler velocimeter.

    Science.gov (United States)

    Avidor, J M

    1974-02-01

    A laser Doppler velocimeter capable of directly measuring instantaneous velocities is described. The new LDV uses a novel detection technique based on the utilization of a static slightly defocused spherical Fabry-Perot interferometer used in conjunction with a special mask for the detection of instantaneous Doppler frequency shifts. The essential characteristics of this LDV are discussed, and such a system recently developed is described. Results of turbulent flow measurements show good agreement with data obtained using hot wire anemometry.

  10. Infant Emotional and Cortisol Responses to Goal Blockage

    Science.gov (United States)

    Lewis, Michael; Ramsay, Douglas

    2005-01-01

    This study examined the relation of infant emotional responses of anger and sadness to cortisol response in 2 goal blockage situations. One goal blockage with 4-month-old infants (N=56) involved a contingency learning procedure where infants' learned response was no longer effective in reinstating an event. The other goal blockage with 6-month-old…

  11. The instantaneous frequency rate spectrogram

    Science.gov (United States)

    Czarnecki, Krzysztof

    2016-01-01

    An accelerogram of the instantaneous phase of signal components referred to as an instantaneous frequency rate spectrogram (IFRS) is presented as a joint time-frequency distribution. The distribution is directly obtained by processing the short-time Fourier transform (STFT) locally. A novel approach to amplitude demodulation based upon the reassignment method is introduced as a useful by-product. Additionally, an estimator of energy density versus the instantaneous frequency rate (IFR) is proposed and referred to as the IFR profile. The energy density is estimated based upon both the classical energy spectrogram and the IFRS smoothened by the median filter. Moreover, the impact of an analyzing window width, additive white Gaussian noise and observation time is tested. Finally, the introduced method is used for the analysis of the acoustic emission of an automotive engine. The recording of the engine of a Lamborghini Gallardo is analyzed as an example.

  12. Analysis of local subassembly accident in KALIMER

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Young Min; Jeong, Kwan Seong; Hahn, Do Hee

    2000-10-01

    Subassembly Accidents (S-A) in the Liquid Metal Reactor (LMR) may cause extensive clad and fuel melting and are thus regarded as a potential whole core accident initiator. The possibility of S-A occurrence must be very low frequency by the design features, and reactor must have specific instrumentation to interrupt the S-A sequences by causing a reactor shutdown. The evaluation of the relevant initiators, the event sequences which follow them, and their detection are the essence of the safety issue. Particularly, the phenomena of flow blockage caused by foreign materials and/or the debris from the failed fuel pin have been researched world-widely. The foreign strategies for dealing with the S-A and the associated safety issues with experimental and theoretical R and D results are reviewed. This report aims at obtaining information to reasonably evaluate the thermal-hydraulic effect of S-A for a wire-wrapped LMR fuel pin bundle. The mechanism of blockage formation and growth within a pin bundle and at the subassembly entrance is reviewed in the phenomenological aspect. Knowledge about the recent LMR subassembly design and operation procedure to prevent flow blockage will be reflected for KALIMER design later. The blockage analysis method including computer codes and related analytical models are reviewed. Especially SABRE4 code is discussed in detail. Preliminary analyses of flow blockage within a 271-pin driver subassembly have been performed using the SABRE4 computer code. As a result no sodium boiling occurred for the central 24-subchannel blockage as well as 6-subchannel blockage.

  13. Infant Emotional and Cortisol Responses to Goal Blockage

    OpenAIRE

    Lewis, Michael; Ramsay, Douglas

    2005-01-01

    This study examined the relation of infant emotional responses of anger and sadness to cortisol response in 2 goal blockage situations. One goal blockage with 4-month-old infants (N = 56) involved a contingency learning procedure where infants’ learned response was no longer effective in reinstating an event. The other goal blockage with 6-month-old infants (N = 84) involved the still face procedure where infants’ reactions to their mothers’ lack of responsivity were not effective in reestabl...

  14. Identification of partial blockages in pipelines using genetic algorithms

    Indian Academy of Sciences (India)

    PRASHANTH REDDY HANMAIAHGARI; M ELKHOLY; CYRUS K RIAHI-NEZHAD

    2017-09-01

    A methodology to identify the partial blockages in a simple pipeline using genetic algorithms for non-harmonic flows is presented in this paper. A sinusoidal flow generated by the periodic on-and-off operation of a valve at the outlet is investigated in the time domain and it is observed that pressure variation at the valve is influenced by the opening size of blockage and its location. In this technique, the unsteady (steady oscillatory) pressure time series at only one location is required to identify two blockages. In the proposed methodology, thesolution of the governing hyperbolic PDEs of pipe flow is obtained using the method of characteristics. For any piping system similar to the hypothetical pipe system used in the simulations, generalized best amplitude and best frequency of the valve operation are determined, which give maximum deviation in pressure responses for a specific blockage at different locations for a given constant-head reservoir. The generalized best amplitude and best frequency of the valve operation are also obtained for two blockages. Accuracy of the proposed methodology in identifying blockages in a hypothetical simple pipe system with increased noise in the simulated measurements is studied. A non-dimensional variable is proposed to determine whether the proposed methodology is applicable to isolate partial blockages in a piping system. Finally, the proposed methodology is experimentally validated on a laboratory piping system for a single blockage and two blockages.

  15. Effect of Flow Blockage on the Coolability during Reflood in a 2 × 2 Rod Bundle

    Directory of Open Access Journals (Sweden)

    Kihwan Kim

    2014-01-01

    Full Text Available During the reflood phase of a large-break loss-of-coolant accident (LBLOCA in a pressurized-water reactor (PWR, the fuel rods can be ballooned or rearranged owing to an increase in the temperature and internal pressure of the fuel rods. In this study, an experimental study was performed to understand the thermal behavior and effect of the ballooned region on the coolability using a 2 × 2 rod bundle test facility. The electrically heated rod bundle was used and the ballooning shape of the rods was simulated by superimposing hollow sleeves, which have a 90% blockage ratio. Forced reflood tests were performed to examine the transient two-phase heat transfer behavior for different reflood rates and rod powers. The droplet behaviors were also investigated by measuring the velocity and size of droplets near the blockage region. The results showed that the heat transfer was enhanced in the downstream of the blockage region, owing to the reduced flow area of the subchannel, intensification of turbulence, and deposition of the droplet.

  16. Inhibiting bacterial toxins by channel blockage.

    Science.gov (United States)

    Bezrukov, Sergey M; Nestorovich, Ekaterina M

    2016-03-01

    Emergent rational drug design techniques explore individual properties of target biomolecules, small and macromolecule drug candidates, and the physical forces governing their interactions. In this minireview, we focus on the single-molecule biophysical studies of channel-forming bacterial toxins that suggest new approaches for their inhibition. We discuss several examples of blockage of bacterial pore-forming and AB-type toxins by the tailor-made compounds. In the concluding remarks, the most effective rationally designed pore-blocking antitoxins are compared with the small-molecule inhibitors of ion-selective channels of neurophysiology. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Asymptotic Rayleigh instantaneous unit hydrograph

    Science.gov (United States)

    Troutman, B.M.; Karlinger, M.R.

    1988-01-01

    The instantaneous unit hydrograph for a channel network under general linear routing and conditioned on the network magnitude, N, tends asymptotically, as N grows large, to a Rayleigh probability density function. This behavior is identical to that of the width function of the network, and is proven under the assumption that the network link configuration is topologically random and the link hydraulic and geometric properties are independent and identically distributed random variables. The asymptotic distribution depends only on a scale factor, {Mathematical expression}, where ?? is a mean link wave travel time. ?? 1988 Springer-Verlag.

  18. Decision Support System for Blockage Management in Fire Service

    Directory of Open Access Journals (Sweden)

    Krasuski Adam

    2014-08-01

    Full Text Available In this article we present the foundations of a decision support system for blockage management in Fire Service. Blockage refers to the situation when all fire units are out and a new incident occurs. The approach is based on two phases: off-line data preparation and online blockage estimation. The off-line phase consists of methods from data mining and natural language processing and results in semantically coherent information granules. The online phase is about building the probabilistic models that estimate the block-age probability based on these granules. Finally, the selected classifier judges whether a blockage can occur and whether the resources from neighbour fire stations should be asked for assistance.

  19. Blockage Detection in Circular Pipe Using Vibration Analysis

    Directory of Open Access Journals (Sweden)

    N. L. T. Lile

    2012-01-01

    Full Text Available Pipe is an important medium used in most industrial and home applications for transferring liquid or gas from one end to the other. The efficiency of liquid flow is crucial to ensure proper and efficient delivering of medium carried. Liquid flow may be abrupt or ceased if blockage forms inside the circular pipe. This paper investigates the effect of blockage in circular pipe using vibration measurement. The main focus of this paper is to study the correlation of blockage levels to vibration signal. When fluid flow through an obstacle, the streamlines get closer which will increase the flow velocity and decrease the pressure. The vibration parameters are measured using accelerometer and the relationship between blockage levels to vibration signal are observed. It is found that vibration in pipe increases as the flow area gets smaller. This work expresses the potential of vibration analysis in assessing blockage inside a circular pipe with direct water flow.

  20. Probability safety assessment for MACSTOR/KN-400 during the air inlet blockage

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jung Hyun

    2005-02-15

    Spent fuels extracted from a reactor can be reused or be deposited to all eternity. Before they are chosen between these two ways, spent fuels are stored in the intermediate storage. The spent fuel dry storage facility is an intermediate storage using air-cooling method. In Korea, because of the current situation, spent fuels derived from continuous operation of PHWRs cannot be stored in a pool, spent fuel dry storage facility is scheduled to be built by year 2016. Therefore, the use of PSA technology for designing spent fuel intermediate storage facility needs to be developed. In this study, the safety analysis for the sequence of air inlet blockage accident in spent fuel dry storage facility is analyzed and the safety analysis of spent fuel dry storage facility is classified in three phase. In first phase, the destruction probability of a basket and a cylinder, which are the major elements of containing radioactive substances, is modeled and the destruction of probability of a basket is 1.1x10{sup -3}. In second phase, the release probability of radiation material in spent fuel dry storage facility are modeled and the annual release frequency of radiation material in spent fuel dry storage facility is 1.4x10{sup -7}. Finally, consequence analysis through modeling circumference areas is performed. In case of spent fuel dry storage facilities, the studies up to now are only the accident modeling of spent fuel dry storage facility and are performed with only deterministic analysis. Therefore, in this study, the analysis for the accident of air inlet blockage is performed concentrating on PSA(Probability Safety Assessment). As a result of assessment, spent fuel dry storage facility is more safe than nuclear power plants.

  1. Physiological blockage in plants in response to postharvest stress ...

    African Journals Online (AJOL)

    Physiological blockage in plants in response to postharvest stress. ... African Journal of Biotechnology. Journal Home · ABOUT ... However, ornamental plants are used in floral arrangements in vases and have limited shelf-life. Thus, this study ...

  2. Instantaneous polarization statistics of electromagnetic waves

    Institute of Scientific and Technical Information of China (English)

    WANG Xuesong; LI Yongzhen; DAI Dahai; XIAO Shunping; ZHUANG Zhaowen

    2004-01-01

    The problem of statistical description of instantaneous polarization of electromagnetic waves is studied. First, the physical meanings of instantaneous Stokes vectors' components are analyzed, which provide a short cut for solving statistical distribution functions of instantaneous Stokes vectors. Second, in the condition of Gaussian hypothesis, the analytical expressions of probability density function (PDF) of instantaneous Stokes vectors are presented. Finally, some computation results are presented in the condition of two independent polarization channels, which show the validity and simplicity of the statistical description method.

  3. Parametric study of the potential for BWR ECCS strainer blockage due to LOCA generated debris. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Zigler, G.; Brideau, J.; Rao, D.V.; Shaffer, C.; Souto, F.; Thomas, W. [Science and Engineering Associates, Inc., Albuquerque, NM (United States)

    1995-10-01

    This report documents a plant-specific study for a BWR/4 with a Mark I containment that evaluated the potential for LOCA generated debris and the probability of losing long term recirculation capability due ECCS pump suction strainer blockage. The major elements of this study were: (1) acquisition of detailed piping layouts and installed insulation details for a reference BWR; (2) analysis of plant specific piping weld failure probabilities to estimate the LOCA frequency; (3) development of an insulation and other debris generation and drywell transport models for the reference BWR; (4) modeling of debris transport in the suppression pool; (5) development of strainer blockage head loss models for estimating loss of NPSH margin; (6) estimation of core damage frequency attributable to loss of ECCS recirculation capability following a LOCA. Elements 2 through 5 were combined into a computer code, BLOCKAGE 2.3. A point estimate of overall DEGB pipe break frequency (per Rx-year) of 1.59E-04 was calculated for the reference plant, with a corresponding overall ECCS loss of NPSH frequency (per Rx-year) of 1.58E-04. The calculated point estimate of core damage frequency (per Rx-year) due to blockage related accident sequences for the reference BWR ranged from 4.2E-06 to 2.5E-05. The results of this study show that unacceptable strainer blockage and loss of NPSH margin can occur within the first few minutes after ECCS pumps achieve maximum flows when the ECCS strainers are exposed to LOCA generated fibrous debris in the presence of particulates (sludge, paint chips, concrete dust). Generic or unconditional extrapolation of these reference plant calculated results should not be undertaken.

  4. Bicycle accidents.

    Science.gov (United States)

    Lind, M G; Wollin, S

    1986-01-01

    Information concerning 520 bicycle accidents and their victims was obtained from medical records and the victims' replies to questionnaires. The analyzed aspects included risk of injury, completeness of accident registrations by police and in hospitals, types of injuries and influence of the cyclists' age and sex, alcohol, fatigue, hunger, haste, physical disability, purpose of cycling, wearing of protective helmet and other clothing, type and quality of road surface, site of accident (road junctions, separate cycle paths, etc.) and turning manoeuvres.

  5. Reflood experiments in rod bundles with flow blockages due to clad ballooning

    Energy Technology Data Exchange (ETDEWEB)

    Moon, S.K.; Kim, J.; Kim, K.; Kim, B.J.; Park, J.K.; Youn, Y.J.; Choi, H.S.; Song, C.H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-07-15

    Clad ballooning and the resulting partial flow blockage are one of the major thermal-hydraulic concerns associated with the coolability of partially blocked cores during a loss-of-coolant accident (LOCA). Several in-pile tests have shown that fuel relocation causes a local power accumulation and a high thermal coupling between the clad and fuel debris in the ballooned regions. However, previous experiments in the 1980s did not take into account the fuel relocation phenomena and resulting local power increase in the ballooned regions. The present paper presents the results of systematic investigations on the coolability of rod bundles with flow blockages. The experiments were mainly performed in 5 x 5 rod bundles, 2 x 2 rod bundles and other test facilities. The experiments include a reflood heat transfer, single-phase convective heat transfer, flow redistributions phenomena, and droplet break-up behavior. The effects of the fuel relocation and resulting local power increase were investigated using a 5 x 5 rod bundle. The fuel relocation phenomena increase the peak cladding temperature.

  6. Microstructural analysis of MTR fuel plates damaged by a coolant flow blockage

    Science.gov (United States)

    Leenaers, A.; Joppen, F.; Van den Berghe, S.

    2009-10-01

    In 1975, as a result of a blockage of the coolant inlet flow, two plates of a fuel element of the BR2 reactor of the Belgian Nuclear Research Centre (SCK•CEN) were partially melted. The fuel element consisted of Al-clad plates with 90% 235U enriched UAl x fuel dispersed in an Al matrix. The element had accumulated a burn up of 21% 235U before it was removed from the reactor. Recently, the damaged fuel plates were sent to the hot laboratory for detailed PIE. Microstructural changes and associated temperature markers were used to identify several stages in the progression to fuel melting. It was found that the temperature in the center of the fuel plate had increased above 900-950 °C before the reactor was scrammed. In view of the limited availability of such datasets, the results of this microstructural analysis provide valuable input in the analysis of accident scenarios for research reactors.

  7. Advanced neutron source reactor probabilistic flow blockage assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, C.T.

    1995-08-01

    The Phase I Level I Probabilistic Risk Assessment (PRA) of the conceptual design of the Advanced Neutron Source (ANS) Reactor identified core flow blockage as the most likely internal event leading to fuel damage. The flow blockage event frequency used in the original ANS PRA was based primarily on the flow blockage work done for the High Flux Isotope Reactor (HFIR) PRA. This report examines potential flow blockage scenarios and calculates an estimate of the likelihood of debris-induced fuel damage. The bulk of the report is based specifically on the conceptual design of ANS with a 93%-enriched, two-element core; insights to the impact of the proposed three-element core are examined in Sect. 5. In addition to providing a probability (uncertainty) distribution for the likelihood of core flow blockage, this ongoing effort will serve to indicate potential areas of concern to be focused on in the preliminary design for elimination or mitigation. It will also serve as a loose-parts management tool.

  8. An overview of the BWR ECCS strainer blockage issues

    Energy Technology Data Exchange (ETDEWEB)

    Serkiz, A.W.; Marshall, M.L. Jr.; Elliott, R. [Nuclear Regulatory Commission, Washington, DC (United States)

    1996-03-01

    This Paper provides a brief overview of actions taken in the mid 1980s to resolve Unresolved Safety Issue (USI) A-43, {open_quotes}Containment Emergency Sump Performance,{close_quotes} and their relationship to the BWR strainer blockage issue; the importance of insights gained from the Barseback-2 (a Swedish BWR) incident in 1992 and from ECCS strainer testing and inspections at the Perry nuclear power plant in 1992 and 1993; an analysis of an US BWR/4 with a Mark I containment; an international community sharing of knowledge relevant to ECCS strainer blockage, additional experimental programs; and identification of actions needed to resolve the strainer blockage issue and the status of such efforts.

  9. Automatic traveltime picking using instantaneous traveltime

    KAUST Repository

    Saragiotis, Christos

    2013-02-08

    Event picking is used in many steps of seismic processing. We present an automatic event picking method that is based on a new attribute of seismic signals, instantaneous traveltime. The calculation of the instantaneous traveltime consists of two separate but interrelated stages. First, a trace is mapped onto the time-frequency domain. Then the time-frequency representation is mapped back onto the time domain by an appropriate operation. The computed instantaneous traveltime equals the recording time at those instances at which there is a seismic event, a feature that is used to pick the events. We analyzed the concept of the instantaneous traveltime and demonstrated the application of our automatic picking method on dynamite and Vibroseis field data.

  10. Accident Statistics

    Data.gov (United States)

    Department of Homeland Security — Accident statistics available on the Coast Guard’s website by state, year, and one variable to obtain tables and/or graphs. Data from reports has been loaded for...

  11. Analysis of Post-LOCA Core Inlet Blockage to Evaluate In-vessel Downstream Effect in APR1400

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Young Seok [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    The method was developed to have a conservatism to cover the uncertainty of analysis and the acceptance is judged by the representative bounding estimation. However, the important safety parameters such as the available driving head need to be confirmed by the plant specific calculation. Also an interaction between the debris induced head loss and the core flow rate needs to be explained because the head loss induced by debris in actual condition may reduce the core inflow rate faster. To confirm the safety parameters, in this study, thermal-hydraulic response considering the core inlet blockage (CIB) by debris during LTCC process following a double-ended guillotine break of cold leg (CLB), one of hot leg (HLB) and one of intermediate leg (ILB) of the APR1400 were calculated, respectively. MARS-KS 1.3 code has been used. The CIB has been modeled by the closure of valves to the core in exponential manner with time to observe the behavior near the complete blockage. To understand the effect of core inlet blockage (CIB) during a long term core cooling (LTCC) phase following a loss-of-coolant accident (LOCA) in the light of in-vessel downstream effect (IDE) of Generic Safety Issue (GSI) 191, double-ended guillotine break of hot leg (HLB), one of cold leg (CLB) and one of intermediate leg (ILB) were calculated, respectively. And the important safety parameters such as the available driving head and the head loss due to debris were calculated using MARS-KS code and discussed in comparison with the WCAP method. As a result, a little delayed heatup behavior of the fuel cladding was found for all the cases, which due to the redistribution of flow within the core after blockage.

  12. Instantaneous Formulation for Transitions Between Two Instantaneous Bound States and Its Gauge Invariance

    Institute of Scientific and Technical Information of China (English)

    CHANG Chao-Hsi; CHEN Jiao-Kai; WANG Guo-Li

    2006-01-01

    We have precisely derived a "rigorous instantaneous formulation" for transitions between two bound states when the bound states are well-described by instantaneous Bethe-Salpeter (BS) equation (i.e. the kernel of the equation is instantaneous"occasionally"). The obtained rigorous instantaneous formulation, in fact, is expressed as an operator sandwiched by two "reduced BS wave functions" properly, while the reduced BS wave functions appearing in the formulation are the rigorous solutions of the instantaneous BS equation, and they may relate to Schr(o)dinger wave functions straightforwardly. We also show that the rigorous instantaneous formulation is gauge-invariant with respect to the Uem(1) transformation precisely, if the concerned transitions are radiative. Some applications of the formulation are outlined.

  13. Sports Accidents

    CERN Multimedia

    Kiebel

    1972-01-01

    Le Docteur Kiebel, chirurgien à Genève, est aussi un grand ami de sport et de temps en temps médecin des classes genevoises de ski et également médecin de l'équipe de hockey sur glace de Genève Servette. Il est bien qualifié pour nous parler d'accidents de sport et surtout d'accidents de ski.

  14. Experimental study of blockage of monochromatic waves by counter currents

    NARCIS (Netherlands)

    Suastika, I.K.

    1999-01-01

    Blockage of waves by a current can occur if waves are propagating on a spatially varying opposing current in which the velocity is increasing in the wave propagation direction. The ongoing waves become shorter and steeper while they are propagating against the current. Blocking occurs at the

  15. Turbulet flow in a model nuclear fuel rod bundle containing partial flow blockages

    Energy Technology Data Exchange (ETDEWEB)

    Creer, J.M.; Rowe, D.S.; Bates, J.M.; Sutey, A.M.

    1977-03-01

    Local velocity and turbulence intensity measurements were obtained with a laser Doppler anemometer near flow blockages in an unheated 7 x 7 rod bundle. Sleeve blockages were positioned on the center nine rods to create area reductions of 70 and 90 percent in the center four subchannels of the bundle. Experimental results indicated that severe flow disturbances existed downstream from the blockage clusters and showed that only minor disturbances can be expected upstream from the blockages. Recirculation zones for both 70 and 90 percent blockages were detected downstream from the blockage clusters and persisted for approximately three to five subchannel hydraulic diameters depending on blockage severity. The experimental velocity results obtained with blockage clusters located midway between grid spacers were successfully predicted using the COBRA computer program.

  16. CFD investigation the thermal-hydraulic behavior behind the flow blockage in SFR

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jin; Jeong, J. H.; Chang, W. P; Ha, K. S. [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    It is evident that the flow blockage is basically a local phenomenon, and the main issue to investigate is the thermal-hydraulic behavior of the region downstream from the obstacle because it determines the clad temperature peak. For this reason, a local detailed CFD analysis has been carried out in order to assess the impacts of a flow blockage. The flow blockage events are classified into two types, internal and external blockage, depending on their locations. The objective of this paper is to investigate the influence caused by a flow blockage. A CFD analysis using fully resolved RANS simulations has been carried on the fluid flow and heat transfer in the case of a flow blockage for fuel assemblies in a PGSFR. A fuel assembly with 91 pins instead of all 217 pins was considered for this study. Two main effects can be distinguished in a flow blockage: a locally lower mass flow rate in the wake/recirculation region downstream of the blockage, and the peak temperature behind the blockage. Both of them are closely related. The recirculation region exists within a short distance downstream from the blockage, and it has an effect on the cladding integrity. The maximum cladding temperature is about 1000 .deg. C and is located in the central pins of the blockage region. It could lead to a rupture of the cladding. From these analysis results, the axial blockage size may have a significant impact on the clad integrity.

  17. Neutronics aspects associated to the prevention and mitigation of severe accidents in sodium cooled reactor cores; Aspects de neutronique associes a la prevention et a la reduction des accidents graves dans les coeurs de reacteurs a caloporteur sodium

    Energy Technology Data Exchange (ETDEWEB)

    Poumerouly, S.

    2010-12-15

    Among all the types of accidents to be considered for the safety licensing of a plant, some have a very low probability of occurrence but might have very important consequences: the severe accidents or Hypothetical Core Disruptive Accidents (HCDA). The studies on the scenario of these accidents are performed in parallel to the prevention studies. In this PhD report, two representative safety cases are studied: the Unprotected Loss Of Flow (ULOF) and the Total Instantaneous Blockage (TIB). The objectives are to understand what causes the reactivity increase during these accidents and to find means to reduce the energetic release of the scenario (ULOF) or to find ways to trigger the core prior to the propagation of the accident (TIB). At first, the accidents are studied in static calculations with the ERANOS code system. The accidents are divided into several steps and the reactivity insertions at each step are explained. This study shows the importance of the removal of the structures as well as of the radial leakage changes during the core slumping-down. The study also gives the amounts of fuel to be ejected or of absorber to be injected in both accidents. These values give tracks to the following more accurate studies, the transient studies. The transient studies were performed with the SIMMER code system, coupling thermo-hydraulics and neutronics. SIMMER data and algorithms have been improved so as to better predict ERANOS results (former discrepancies were up to 1.5$). The SIMMER reactivity calculation is improved by 0.8$ with variations of reactivity due to the motion of materials correctly predicted. A new algorithm for the {beta}-effective was implemented in SIMMER so as to be more accurate and easier to manage. SIMMER is then used to calculate the secondary phase of the ULOF, while the primary phase is calculated with ERANOS thanks to some assumptions. The assumptions are very much based on the fact that the movement of materials stops whenever the energy

  18. Instantaneous translocation statuses on the fluctuation of ionic current for DNA through graphene nanopore

    CERN Document Server

    Lv, Wenping

    2013-01-01

    Graphene nanopore has the ultra-high DNA sequencing sensitivity for the atomic thickness and excellent electronic properties. Extracting the sequence information of DNA from the blocked ionic current is the crucial step for the ionic current based sequencing technology on nanopores. In this letter, the investigation of the effect of measurement induced noise of ionic current as well as the instantaneous translocation statuses from the fluctuation of ionic current signals for DNA through a graphene nanopore was carried out based on molecular dynamics simulations. We found that the molecular thermal noise of ionic current in a graphene nanopore was related with the time interval of measurement, and the tiny conformational and dynamical variations of DNA could be revealed from the fluctuation of the denoised ionic current through a graphene nanopore. Additionally, the neighborhood effect of ionic current blockage for DNA near a graphene nanopore (within 1.5 nm) was observed. These findings suggest that the ionic...

  19. Analysis of flow blockage of a single RBMK channel

    Energy Technology Data Exchange (ETDEWEB)

    Franco Pierro; Iljiana Ivekovic; Parisi Carlo; Francesco D' Auria [University of Pisa, Department of Mechanical, Nuclear and Production Engineering - DMNP, Via Diotisalvi 2, 56122 Pisa (Italy)

    2005-07-01

    Full text of publication follows: The main aim of the following study is to perform an evaluation of a single RBMK reactor core channel and of its surrounding graphite structures in case of flow blockage. The paper presents an evaluation of the event with RELAP5 and FRAP code. The RBMK channel, the graphite stack and the He-N gap is modelled with the RELAP code and the thermo-mechanical fuel rod behaviour is studied by FRAP code. Two cases are analysed in order to demonstrate if the propagation of the break occurs: in the first case a single break in the pressure tube is postulated, in the second, a modelling of the pressure tube break propagation is studied. A blockage of 100% of the total flow area is considered. The paper concludes that the Pressure tube is broken and the propagation occurs, the ballooning does not appear. (authors)

  20. Topology Design for Directional Range Extension Networks with Antenna Blockage

    Science.gov (United States)

    2016-11-01

    Topology Design for Directional Range Extension Networks with Antenna Blockage Thomas Shake MIT Lincoln Laboratory shake@ll.mit.edu Abstract...algorithms that optimize this criterion. ACKNOWLEDGEMENTS The author would like to thank Terrance Gibbons of MIT Lincoln Laboratory’s Tactical...Com- puter Networks, Vol 51, pp. 4237-4251, 2007 [11] T. Cormen, C. Leiserson, R. Rivest, and C. Stein, Introduction to Algorithms (3rd ed.). MIT

  1. Structural relaxation monitored by instantaneous shear modulus

    DEFF Research Database (Denmark)

    Olsen, Niels Boye; Dyre, Jeppe; Christensen, Tage Emil

    1998-01-01

    This paper reports on aging of the silicone oil MS704 for sudden changes of temperature from 210.5 to 209.0 K and from 207.5 to 209.0 K studied by continuously monitoring the instantaneous shear modulus G [infinity]. The results are interpreted within the Tool-Narayanaswamy formalism with a reduc...

  2. Accident: Reminder

    CERN Document Server

    2003-01-01

    There is no left turn to Point 1 from the customs, direction CERN. A terrible accident happened last week on the Route de Meyrin just outside Entrance B because traffic regulations were not respected. You are reminded that when travelling from the customs, direction CERN, turning left to Point 1 is forbidden. Access to Point 1 from the customs is only via entering CERN, going down to the roundabout and coming back up to the traffic lights at Entrance B

  3. Predicting trend reversals using market instantaneous state

    Science.gov (United States)

    Bury, Thomas

    2014-06-01

    Collective behaviors taking place in financial markets reveal strongly correlated states especially during a crisis period. A natural hypothesis is that trend reversals are also driven by mutual influences between the different stock exchanges. Using a maximum entropy approach, we find coordinated behavior during trend reversals dominated by the pairwise component. In particular, these events are predicted with high significant accuracy by the ensemble's instantaneous state.

  4. Instantaneous Relaying: Optimal Strategies and Interference Neutralization

    CERN Document Server

    Ho, Zuleita

    2012-01-01

    In a multi-user wireless network equipped with multiple relay nodes, some relays are more intelligent than other relay nodes. The intelligent relays are able to gather channel state information, perform linear processing and forward signals whereas the dumb relays is only able to serve as amplifiers. As the dumb relays are oblivious to the source and destination nodes, the wireless network can be modeled as a relay network with *smart instantaneous relay* only: the signals of source-destination arrive at the same time as source-relay-destination. Recently, instantaneous relaying is shown to improve the degrees-of-freedom of the network as compared to classical cut-set bound. In this paper, we study an achievable rate region and its boundary of the instantaneous interference relay channel in the scenario of (a) uninformed non-cooperative source-destination nodes (source and destination nodes are not aware of the existence of the relay and are non-cooperative) and (b) informed and cooperative source-destination...

  5. Influence of blockage effect on measurement by vane anemometers

    Directory of Open Access Journals (Sweden)

    Sluse Jan

    2017-01-01

    Full Text Available The article deals with influence of blockage effect caused by vane anemometer in the wind tunnel by measurement via this anemometer. The influences will be represented by correction coefficient. The first part of this article is focused on the design of the impeller of vane anemometers. The impellers are printed on 3D printer with variable parameters. The anemometer is fixed in an open section of the wind tunnel with closed loop and the velocity profile is measured by Laser Doppler velocimetry (LDV in front and behind it for all impellers. The experimental data are compared with the numerical simulation in OpenFOAM. The results are correction coefficients.

  6. Instantaneous Current Feedback Control Strategy on Buck Mode Inverter

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Control strategies for Buck mode inverter have important effect on static and dynamic characteristics, reliability, load capacity, and short-circuit resistance. Instantaneous current feedback control strategies include instantaneous inductor current feedback control and instantaneous capacitor current feedback control, both of which have essential difference. When the Buck mode inverter respectively adopts instantaneous inductor current and capacitor current feedback control strategies, characteristics of stability, output voltage and power, short circuit, nonlinear load and dynamic are fully investigated in this paper.

  7. ANS severe accident program overview & planning document

    Energy Technology Data Exchange (ETDEWEB)

    Taleyarkhan, R.P.

    1995-09-01

    The Advanced Neutron Source (ANS) severe accident document was developed to provide a concise and coherent mechanism for presenting the ANS SAP goals, a strategy satisfying these goals, a succinct summary of the work done to date, and what needs to be done in the future to ensure timely licensability. Guidance was received from various bodies [viz., panel members of the ANS severe accident workshop and safety review committee, Department of Energy (DOE) orders, Nuclear Regulatory Commission (NRC) requirements for ALWRs and advanced reactors, ACRS comments, world-wide trends] were utilized to set up the ANS-relevant SAS goals and strategy. An in-containment worker protection goal was also set up to account for the routine experimenters and other workers within containment. The strategy for achieving the goals is centered upon closing the severe accident issues that have the potential for becoming certification issues when assessed against realistic bounding events. Realistic bounding events are defined as events with an occurrency frequency greater than 10{sup {minus}6}/y. Currently, based upon the level-1 probabilistic risk assessment studies, the realistic bounding events for application for issue closure are flow blockage of fuel element coolant channels, and rapid depressurization-related accidents.

  8. Measurement and Analysis of Sodium Void Reactivity Effect in CEFR

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The sodium void reactivity effect (SVRE) is one of the important parameters in the design and safety analysis of sodium-cooled fast reactors. In some serious accident conditions, for example the total instantaneous blockage (TIB) accident,

  9. Instantaneous aerosol dynamics in a turbulent flow

    KAUST Repository

    Zhou, Kun

    2012-01-01

    Dibutyl phthalate aerosol particles evolution dynamics in a turbulent mixing layer is simulated by means of direct numerical simulation for the flow field and the direct quadrature method of moments for the aerosol evolution. Most par-ticles are nucleated in a thin layer region corresponding to a specific narrow temperature range near the cool stream side. However, particles undergo high growth rate on the hot stream side due to condensation. Coagulation decreases the total particle number density at a rate which is highly correlated to the in-stantaneous number density.

  10. Instantaneous frequencies of a chaotic system

    Indian Academy of Sciences (India)

    C Chandre; T Uzer

    2005-03-01

    The structure and geometry of high-dimensional, complex dynamical systems is usually hidden under a profusion of numerical data. We show that time–frequency analysis allows one to analyze these data regardless of the number of degrees of freedom. Our method takes snapshots of the system in terms of its instantaneous frequencies defined as ridges of the time–frequency landscape. Using the wavelet transform of a single trajectory, it can characterize key dynamical properties like the extent of chaos, resonance transitions and trappings.

  11. Self-reported accidents

    DEFF Research Database (Denmark)

    Møller, Katrine Meltofte; Andersen, Camilla Sloth

    2016-01-01

    The main idea behind the self-reporting of accidents is to ask people about their traffic accidents and gain knowledge on these accidents without relying on the official records kept by police and/or hospitals.......The main idea behind the self-reporting of accidents is to ask people about their traffic accidents and gain knowledge on these accidents without relying on the official records kept by police and/or hospitals....

  12. Gesture recognition by instantaneous surface EMG images.

    Science.gov (United States)

    Geng, Weidong; Du, Yu; Jin, Wenguang; Wei, Wentao; Hu, Yu; Li, Jiajun

    2016-11-15

    Gesture recognition in non-intrusive muscle-computer interfaces is usually based on windowed descriptive and discriminatory surface electromyography (sEMG) features because the recorded amplitude of a myoelectric signal may rapidly fluctuate between voltages above and below zero. Here, we present that the patterns inside the instantaneous values of high-density sEMG enables gesture recognition to be performed merely with sEMG signals at a specific instant. We introduce the concept of an sEMG image spatially composed from high-density sEMG and verify our findings from a computational perspective with experiments on gesture recognition based on sEMG images with a classification scheme of a deep convolutional network. Without any windowed features, the resultant recognition accuracy of an 8-gesture within-subject test reached 89.3% on a single frame of sEMG image and reached 99.0% using simple majority voting over 40 frames with a 1,000 Hz sampling rate. Experiments on the recognition of 52 gestures of NinaPro database and 27 gestures of CSL-HDEMG database also validated that our approach outperforms state-of-the-arts methods. Our findings are a starting point for the development of more fluid and natural muscle-computer interfaces with very little observational latency. For example, active prostheses and exoskeletons based on high-density electrodes could be controlled with instantaneous responses.

  13. Gesture recognition by instantaneous surface EMG images

    Science.gov (United States)

    Geng, Weidong; Du, Yu; Jin, Wenguang; Wei, Wentao; Hu, Yu; Li, Jiajun

    2016-01-01

    Gesture recognition in non-intrusive muscle-computer interfaces is usually based on windowed descriptive and discriminatory surface electromyography (sEMG) features because the recorded amplitude of a myoelectric signal may rapidly fluctuate between voltages above and below zero. Here, we present that the patterns inside the instantaneous values of high-density sEMG enables gesture recognition to be performed merely with sEMG signals at a specific instant. We introduce the concept of an sEMG image spatially composed from high-density sEMG and verify our findings from a computational perspective with experiments on gesture recognition based on sEMG images with a classification scheme of a deep convolutional network. Without any windowed features, the resultant recognition accuracy of an 8-gesture within-subject test reached 89.3% on a single frame of sEMG image and reached 99.0% using simple majority voting over 40 frames with a 1,000 Hz sampling rate. Experiments on the recognition of 52 gestures of NinaPro database and 27 gestures of CSL-HDEMG database also validated that our approach outperforms state-of-the-arts methods. Our findings are a starting point for the development of more fluid and natural muscle-computer interfaces with very little observational latency. For example, active prostheses and exoskeletons based on high-density electrodes could be controlled with instantaneous responses. PMID:27845347

  14. Instantaneous network RTK in Orange County, California

    Science.gov (United States)

    Bock, Y.

    2003-04-01

    The Orange County Real Time GPS Network (OCRTN) is an upgrade of a sub-network of SCIGN sites in southern California to low latency (1-2 sec), high-rate (1 Hz) data streaming, analysis, and dissemination. The project is a collaborative effort of the California Spatial Reference Center (CSRC) and the Orange County Public Resource and Facilities Division, with partners from the geophysical community, local and state government, and the private sector. Currently, ten sites are streaming 1 Hz raw data (Ashtech binary MBEN format) by means of dedicated, point-to-point radio modems to a network hub that translates the asynchronous serial data to TCP/IP and onto a PC workstation residing on a local area network. Software residing on the PC allows multiple clients to access the raw data simultaneously though TCP/IP. One of the clients is a Geodetics RTD server that receives and archives (1) the raw 1 Hz network data, (2) estimates of instantaneous positions and zenith tropospheric delays for quality control and detection of ground motion, and (3) RINEX data to decimated to 30 seconds. Data recovery is typically 99-100%. The server also produces 1 Hz RTCM data (messages 18, 19, 3 and 22) that are available by means of TCP/IP to RTK clients with wireless Internet modems. Coverage is excellent throughout the county. The server supports standard RTK users and is compatible with existing GPS instrumentation. Typical latency is 1-2 s, with initialization times of several seconds to minutes OCRTN site spacing is 10-15 km. In addition, the server supports “smart clients” who can retrieve data from the closest n sites (typically 3) and obtain an instantaneous network RTK position with 1-2 s latency. This mode currently requires a PDA running the RTD client software, and a wireless card. Since there is no initialization and re-initialization required this approach is well suited to support high-precision (centimeter-level) dynamic applications such as intelligent transportation

  15. Improving the Gas Instantaneous Water Heaters Performances

    Directory of Open Access Journals (Sweden)

    Nasir Kloub

    2005-01-01

    Full Text Available This study presents a study of a theoretical and practical investigation of the gas Instantaneous (Tankless water Heaters performance. The results allow us to obtain realistic values of the control system in the various capacities gaseous flowing water heaters. The objective of this work is to study the operation of the plans in the field of controlling and checking low capacity gaseous flowing water in order to choose the proper plan of the logical values and measures for these equipments that may be used in industrial conditions. Also results of the work proved to be accurate. A design of the control system was made. The results of the practical experiment of the control system were similar to the arithmetic results.

  16. Numerical modelling of instantaneous plate tectonics

    Science.gov (United States)

    Minster, J. B.; Haines, E.; Jordan, T. H.; Molnar, P.

    1974-01-01

    Assuming lithospheric plates to be rigid, 68 spreading rates, 62 fracture zones trends, and 106 earthquake slip vectors are systematically inverted to obtain a self-consistent model of instantaneous relative motions for eleven major plates. The inverse problem is linearized and solved iteratively by a maximum-likelihood procedure. Because the uncertainties in the data are small, Gaussian statistics are shown to be adequate. The use of a linear theory permits (1) the calculation of the uncertainties in the various angular velocity vectors caused by uncertainties in the data, and (2) quantitative examination of the distribution of information within the data set. The existence of a self-consistent model satisfying all the data is strong justification of the rigid plate assumption. Slow movement between North and South America is shown to be resolvable.

  17. Regularization of Instantaneous Frequency Attribute Computations

    Science.gov (United States)

    Yedlin, M. J.; Margrave, G. F.; Van Vorst, D. G.; Ben Horin, Y.

    2014-12-01

    We compare two different methods of computation of a temporally local frequency:1) A stabilized instantaneous frequency using the theory of the analytic signal.2) A temporally variant centroid (or dominant) frequency estimated from a time-frequency decomposition.The first method derives from Taner et al (1979) as modified by Fomel (2007) and utilizes the derivative of the instantaneous phase of the analytic signal. The second method computes the power centroid (Cohen, 1995) of the time-frequency spectrum, obtained using either the Gabor or Stockwell Transform. Common to both methods is the necessity of division by a diagonal matrix, which requires appropriate regularization.We modify Fomel's (2007) method by explicitly penalizing the roughness of the estimate. Following Farquharson and Oldenburg (2004), we employ both the L curve and GCV methods to obtain the smoothest model that fits the data in the L2 norm.Using synthetic data, quarry blast, earthquakes and the DPRK tests, our results suggest that the optimal method depends on the data. One of the main applications for this work is the discrimination between blast events and earthquakesFomel, Sergey. " Local seismic attributes." , Geophysics, 72.3 (2007): A29-A33.Cohen, Leon. " Time frequency analysis theory and applications." USA: Prentice Hall, (1995).Farquharson, Colin G., and Douglas W. Oldenburg. "A comparison of automatic techniques for estimating the regularization parameter in non-linear inverse problems." Geophysical Journal International 156.3 (2004): 411-425.Taner, M. Turhan, Fulton Koehler, and R. E. Sheriff. " Complex seismic trace analysis." Geophysics, 44.6 (1979): 1041-1063.

  18. Thermal hydraulic investigations on porous blockage in a prototype sodium cooled fast reactor fuel pin bundle

    Energy Technology Data Exchange (ETDEWEB)

    Raj, M.Naveen; Velusamy, K., E-mail: kvelu@igcar.gov.in; Maity, Ram Kumar

    2016-07-15

    Highlights: • We simulate flow and temperature fields in FBR fuel bundle with porous blockage. • We perform RANS-based CFD simulation for 217 pin bundle of 7 axial pitch lengths. • Flow reduction in fuel bundle due to porous internal blockage is estimated. • Monitoring bulk sodium outlet temperature does not guarantee blockage detection. • Admissible blockage length to avoid sodium boiling is determined. - Abstract: Thermal hydraulic characteristics of sodium flow in a prototype fuel subassembly with porous internal blockage have been investigated by computational fluid dynamics (CFD) simulations. CFD solutions for a subassembly having 217 pin bundle with seven helical pitch length were obtained by parallel processing. The CFD model has been validated against benchmark blockage experiment reported in literature. Wide parametric ranges for blockage radius, porosity, mean particle diameter and location of blockage have been considered. Critical length of blockage that would result in local sodium boiling as a function of aforementioned blockage parameters has been estimated and the parametric zone posing risk of sodium boiling has been identified. Attention has been paid to coolant mixing and flow and temperature fields downstream of the blockage zone. It is seen that for a prototype subassembly with various sections contributing to pressure loss, the total flow reduction is <2.5% for all blockages that can lead to local sodium boiling. This suggests, that global bulk sodium temperature monitoring at subassembly outlet is unlikely to detect slowly growing blockages. Comparing the sodium flow and temperature fields in unblocked and blocked bundles, it is found that the wake-induced temperature non-uniformity persist even upto 3 helical pitch length, highlighting that the sodium temperature non-uniformity at the bundle exit can serve as an efficient blockage indicator, provided that the cross-section temperature is mapped by a proper instrumentation. The peak

  19. Instantaneous phasor method for obtaining instantaneous balanced fundamental components for power quality control and continuous diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, J.S.

    1997-07-01

    This paper introduces an instantaneous phasor method that considers three phases simultaneously. This method produces the instantaneous fundamental balanced components of the polluted voltages or currents. A figure shows three-phase voltages that contain 5% of fundamental magnitude for each order of the 3rd, 5th, 7th, 9th and the 11th harmonics, respectively. Additionally, the voltages have 5% unbalance for all voltage components. A 10% fundamental-frequency zero-sequence component, as well as a 10% fundamental-frequency negative-sequence component are also added to the phase voltages. Furthermore, certain high-frequency pulses arbitrarily given at 5% of a 35th order to represent a possible carrier frequency of power electronic circuits are also included.

  20. Reactor Network Synthesis Based on Instantaneous Objective Function Characteristic Curves

    Institute of Scientific and Technical Information of China (English)

    张治山; 赵文; 王艳丽; 周传光; 袁希钢

    2003-01-01

    It is believed that whether the instantaneous objective function curves of plug-flow-reactor (PFR) and continuous-stirred-tank-reactor (CSTR) overlap or not, they have a consistent changing trend for complex reactions(steady state, isothermal and constant volume). As a result of the relation of the objective functions (selectivity or yield) to the instantaneous objective functions (instantaneous selectivity or instantaneous reaction rate), the optimal reactor network configuration can be determined according to the changing trend of the instantaneous objective function curves. Further, a recent partition strategy for the reactor network synthesis based on the instantaneous objective function characteristic curves is proposed by extending the attainable region partition strategy from the concentration space to the instantaneous objective function-unreacted fraction of key reactant space. In this paper,the instantaneous objective function is closed to be the instantaneous selectivity and several samples axe examined to illustrate the proposed method. The comparison with the previous work indicates it is a very convenient and practical systematic tool of the reactor network synthesis and seems also promising for overcoming the dimension limit of the attainable region partition strategy in the concentration space.

  1. Analysis on the nitrogen drilling accident of Well Qionglai 1 (I: Major inducement events of the accident

    Directory of Open Access Journals (Sweden)

    Yingfeng Meng

    2015-12-01

    Full Text Available Nitrogen drilling in poor tight gas sandstone should be safe because of very low gas production. But a serious accident of fire blowout occurred during nitrogen drilling of Well Qionglai 1. This is the first nitrogen drilling accident in China, which was beyond people's knowledge about the safety of nitrogen drilling and brought negative effects on the development of gas drilling technology still in start-up phase and resulted in dramatic reduction in application of gas drilling. In order to form a correct understanding, the accident was systematically analyzed, the major events resulting in this accident were inferred. It is discovered for the first time that violent ejection of rock clasts and natural gas occurred due to the sudden burst of downhole rock when the fractured tight gas zone was penetrated during nitrogen drilling, which has been named as “rock burst and blowout by gas bomb”, short for “rock burst”. Then all the induced events related to the rock burst are as following: upthrust force on drilling string from rock burst, bridging-off formed and destructed repeatedly at bit and centralizer, and so on. However, the most direct important event of the accident turns out to be the blockage in the blooie pipe from rock burst clasts and the resulted high pressure at the wellhead. The high pressure at the wellhead causes the blooie pipe to crack and trigged blowout and deflagration of natural gas, which is the direct presentation of the accident.

  2. Instantaneous crack detection using dual PZT transducers

    Science.gov (United States)

    Kim, Seung Bum; Sohn, Hoon

    2008-03-01

    A new guided wave based nondestructive testing (NDT) technique is developed to detect crack damage in metallic plates commonly used in aircraft without using prior baseline data or a predetermined decision boundary. In conventional guided wave based techniques, damage is often identified by comparing the "current" data obtained from a potentially damaged condition of a structure with the "past" baseline data collected at the pristine condition of the structure. However, it has been reported that this type of pattern comparison with the baseline data can lead to increased false alarms due to its susceptibility to varying operational and environmental conditions of the structure. In order to tackle this issue, a reference-free damage detection technique is previously developed using two pairs of collocated lead zirconate titanate transducers (PZTs) placed on both sides of a plate. In this study, this reference-free technique is further advanced so that the PZT transducers can be placed only on one side of the specimen. Crack formation creates Lamb wave mode conversion due to a sudden change in the thickness of the structure. Then, the proposed technique instantly detects the appearance of the crack by extracting this mode conversion from the measured Lamb waves. This study suggests a reference-free statistical approach that enables damage classification using only the current data set. Numerical and experimental results are presented to demonstrate the applicability of the proposed technique to instantaneous crack detection.

  3. Modeling Instantaneous Changes In Natural Scenes

    CERN Document Server

    Dhillon, Vikram

    2010-01-01

    This paper proposes a framework for modeling instantaneous changes natural scenes in real time using Lagrangian Particle Framework and a fluid-particle grid approach. This research can be divided into 3 distinct sections: the first one discusses a multi-camera rig that can measure ego-motion accurately up to 88%, how this device becomes the backbone of our framework, and some improvements devised to optimize a know framework for depth maps and 3d structure estimation from a single still image called make3d. The second part discusses the fluid-particle framework to model natural scenes, presents some algorithms that we are using to accomplish this task and we show how an application of our framework can extend make3d to model natural scenes in real time. This part of the research constructs a bridge between computer vision and computer graphics so that now ideas, answers and intuitions that arose in the domain of computer graphics can now be applied to computer vision and natural modeling. The final part of th...

  4. Blockage effect on the flow around a cylinder probe in calibration

    Institute of Scientific and Technical Information of China (English)

    WANG Hong-wei; WEI Jun

    2007-01-01

    Flow around a 2-D cylinder pressure probe placed in uniform flow, free jet flow, and wind tunnel flow was analyzed with potential flow theory and simulated with numerical method. Blockage effect was investigated under several typical flow Mach numbers. The result from numerical simulation shows a similar trend to the one from potential flow method while varies in quantity. Wind tunnel walls accelerate the flow near the probe and thus produce a blockage effect;Boundary of free jet flow, however, decelerates the flow and thus produces a "negative" blockage effect. A maximum incoming Mach number exists when the probe is calibrated in wind tunnel in high subsonic condition due to choking caused by shocks and shock induced separation. The critical Mach number varies with blockage ratio, which makes high Mach number impossible to achieve in large blockage ratio condition. The blockage effect itself is unavoidable for calibration or measurement although a sufficiently small blockage ratio brings minor effect. Correction can be implemented based on the numerical simulation result presented in this paper and further works.

  5. Relativistic bound-state equations for fermions with instantaneous interactions

    NARCIS (Netherlands)

    Suttorp, L.G.

    1979-01-01

    Three types of relativistic bound-state equations for a fermion pair with instantaneous interaction are studied, viz., the instantaneous Bethe-Salpeter equation, the quasi-potential equation, and the two-particle Dirac equation. General forms for the equations describing bound states with arbitrary

  6. The instantaneous shear modulus in the shoving model

    DEFF Research Database (Denmark)

    Dyre, J. C.; Wang, W. H.

    2012-01-01

    We point out that the instantaneous shear modulus G∞ of the shoving model for the non-Arrhenius temperature dependence of viscous liquids’ relaxation time is the experimentally accessible highfrequency plateau modulus, not the idealized instantaneous affine shear modulus that cannot be measured...

  7. Instantaneous frequency based newborn EEG seizure characterisation

    Science.gov (United States)

    Mesbah, Mostefa; O'Toole, John M.; Colditz, Paul B.; Boashash, Boualem

    2012-12-01

    The electroencephalogram (EEG), used to noninvasively monitor brain activity, remains the most reliable tool in the diagnosis of neonatal seizures. Due to their nonstationary and multi-component nature, newborn EEG seizures are better represented in the joint time-frequency domain than in either the time domain or the frequency domain. Characterising newborn EEG seizure nonstationarities helps to better understand their time-varying nature and, therefore, allow developing efficient signal processing methods for both modelling and seizure detection and classification. In this article, we used the instantaneous frequency (IF) extracted from a time-frequency distribution to characterise newborn EEG seizures. We fitted four frequency modulated (FM) models to the extracted IFs, namely a linear FM, a piecewise-linear FM, a sinusoidal FM, and a hyperbolic FM. Using a database of 30-s EEG seizure epochs acquired from 35 newborns, we were able to show that, depending on EEG channel, the sinusoidal and piecewise-linear FM models best fitted 80-98% of seizure epochs. To further characterise the EEG seizures, we calculated the mean frequency and frequency span of the extracted IFs. We showed that in the majority of the cases (>95%), the mean frequency resides in the 0.6-3 Hz band with a frequency span of 0.2-1 Hz. In terms of the frequency of occurrence of the four seizure models, the statistical analysis showed that there is no significant difference( p = 0.332) between the two hemispheres. The results also indicate that there is no significant differences between the two hemispheres in terms of the mean frequency ( p = 0.186) and the frequency span ( p = 0.302).

  8. Effects of Instantaneous Multiband Dynamic Compression on Speech Intelligibility

    Directory of Open Access Journals (Sweden)

    Herzke Tobias

    2005-01-01

    Full Text Available The recruitment phenomenon, that is, the reduced dynamic range between threshold and uncomfortable level, is attributed to the loss of instantaneous dynamic compression on the basilar membrane. Despite this, hearing aids commonly use slow-acting dynamic compression for its compensation, because this was found to be the most successful strategy in terms of speech quality and intelligibility rehabilitation. Former attempts to use fast-acting compression gave ambiguous results, raising the question as to whether auditory-based recruitment compensation by instantaneous compression is in principle applicable in hearing aids. This study thus investigates instantaneous multiband dynamic compression based on an auditory filterbank. Instantaneous envelope compression is performed in each frequency band of a gammatone filterbank, which provides a combination of time and frequency resolution comparable to the normal healthy cochlea. The gain characteristics used for dynamic compression are deduced from categorical loudness scaling. In speech intelligibility tests, the instantaneous dynamic compression scheme was compared against a linear amplification scheme, which used the same filterbank for frequency analysis, but employed constant gain factors that restored the sound level for medium perceived loudness in each frequency band. In subjective comparisons, five of nine subjects preferred the linear amplification scheme and would not accept the instantaneous dynamic compression in hearing aids. Four of nine subjects did not perceive any quality differences. A sentence intelligibility test in noise (Oldenburg sentence test showed little to no negative effects of the instantaneous dynamic compression, compared to linear amplification. A word intelligibility test in quiet (one-syllable rhyme test showed that the subjects benefit from the larger amplification at low levels provided by instantaneous dynamic compression. Further analysis showed that the increase

  9. A Good Solution for Household Based on Fast Waste Water Blockage Detection

    Directory of Open Access Journals (Sweden)

    Mohammad A. Omardin

    2010-01-01

    Full Text Available Problem statement: The waste pipes from the wash basin are always flow in with several waste form kitchen preparation. Due to time consideration the pipe may comes through blockage and need blockage maintenance. Approach: This study presented an invention for early warning blockage detection for a kitchen waste water drain pipe. The waste water pipe some be connected through vertical pipe runs which are usually embedded in the wall. The Fast Waste Water Blockage Detection (FWABET is to create early detection of a blocked waste water level at kitchen appliances means for quick action knowing fluid flow passing through detector and indicates sign and alarm. Results: User society and country will be benefited from FWABET such as restaurants, slaughters house, hotels, hospitals, building developers and plumbing contractors. It is the first invention in Malaysia and can be adapt as a part of building services requirements. Conclusion: It is concluded that by apply the FWABETs, it may reduce the costs and time of blockage waste water blockage drainage maintenance operations.

  10. The structure of instantaneous frequencies of periodic analytic signals

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper, the structure of analytic signals is investigated by means of the relation between analytic signals and functions in the Hardy space. It is shown that an analytic signal is made up of two parts, one depending on the amplitude of the signal and another on the boundary value of an inner function. Based on this result, properties of the instantaneous frequencies of these two parts are studied, and it is found that negative instantaneous frequencies are caused by the amplitude of a signal. Finally, such conditions that an analytic signal is of positive instantaneous frequency are presented.

  11. Computerized intraoperative calculation of instantaneous prosthetic aortic valve area.

    Science.gov (United States)

    DiSesa, V J; Lachman, P; Collins, J J; Cohn, L H

    1988-01-01

    Improved assessment of valve area is essential to understanding the performance of prosthetic valves. The authors studied six patients undergoing aortic valve replacement using mechanical (ME) or porcine (PO) prostheses. Instantaneous cardiac output (CO) (L/min) was measured in the aorta using an ultrasonic flow probe. Left ventricular and aortic pressures (mmHg) were measured using Millar catheters. Data were analyzed using an IBM PC-AT. Valve area (cm2) was determined using Gorlin's formula (AG) and a new formula for instantaneous area derived mathematically and using a theoretic constant. AG, mean (AI) and peak (Apk) instantaneous areas were compared to geometric measures of area (Aactual) in vitro. Peak instantaneous area correlates best with measured area. Intraoperative assessment using the ultrasonic flow probe and computer analysis is helpful in understanding the dynamic properties of prosthetic valves in vivo.

  12. Measurement of ultrashort pulses with a non-instantaneous nonlinearity

    Energy Technology Data Exchange (ETDEWEB)

    DeLong, K.W.; Ladera, C.L.; Trebino, R. [Sandia National Labs., Livermore, CA (United States); Kohler, B.; Wilson, K.R. [California Univ., San Diego, La Jolla, CA (United States). Dept. of Chemistry

    1995-02-01

    We show how non-instantaneous nonlinearities can be used to characterize an ultrashort pulse in an extension of the Frequency-Resolved Optical Gating technique. We demonstrate this principle using the Raman effect in fused silica.

  13. NUMERICAL APPROACH TO DETERMINING INSTANTANEOUS CONTACT REGION FOR CONJUGATE SURFACES

    Institute of Scientific and Technical Information of China (English)

    WANG Taiyong; LI Jingcai; HE Gaiyun; FAN Shengbo; HAO Yongjiang

    2008-01-01

    According to the defect of traditional method of determining instantaneous contact regions for conjugate surfaces, a numerical approach to the determination is proposed. A local coordinate system is built by using the surface unit tangent and unit normal at the contact point. Considering that the gap forming the boundary of instantaneous contact region in the direction of the common normal vectors is given, a system of nonlinear equations is built to find the instantaneous contact boundary in local coordinate system, a modified Powell's hybrid algorithm of finite-difference approximation to the Jacobian used to solve the system. The new method simplifies the task of determining instantaneous contact regions without calculating curvature and relative curvature. The validity of the proposed approach is verified by an example of hypoid gears.

  14. Visualization of Traffic Accidents

    Science.gov (United States)

    Wang, Jie; Shen, Yuzhong; Khattak, Asad

    2010-01-01

    Traffic accidents have tremendous impact on society. Annually approximately 6.4 million vehicle accidents are reported by police in the US and nearly half of them result in catastrophic injuries. Visualizations of traffic accidents using geographic information systems (GIS) greatly facilitate handling and analysis of traffic accidents in many aspects. Environmental Systems Research Institute (ESRI), Inc. is the world leader in GIS research and development. ArcGIS, a software package developed by ESRI, has the capabilities to display events associated with a road network, such as accident locations, and pavement quality. But when event locations related to a road network are processed, the existing algorithm used by ArcGIS does not utilize all the information related to the routes of the road network and produces erroneous visualization results of event locations. This software bug causes serious problems for applications in which accurate location information is critical for emergency responses, such as traffic accidents. This paper aims to address this problem and proposes an improved method that utilizes all relevant information of traffic accidents, namely, route number, direction, and mile post, and extracts correct event locations for accurate traffic accident visualization and analysis. The proposed method generates a new shape file for traffic accidents and displays them on top of the existing road network in ArcGIS. Visualization of traffic accidents along Hampton Roads Bridge Tunnel is included to demonstrate the effectiveness of the proposed method.

  15. Popescu-Rohrlich correlations imply efficient instantaneous nonlocal quantum computation

    OpenAIRE

    Broadbent, Anne

    2015-01-01

    In instantaneous nonlocal quantum computation, two parties cooperate in order to perform a quantum computation on their joint inputs, while being restricted to a single round of simultaneous communication. Previous results showed that instantaneous nonlocal quantum computation is possible, at the cost of an exponential amount of prior shared entanglement (in the size of the input). Here, we show that a linear amount of entanglement suffices, (in the size of the computation), as long as the pa...

  16. Blockage of mitochondrial calcium uniporter prevents iron accumulation in a model of experimental subarachnoid hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Huiying [Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China); Hao, Shuangying; Sun, Xiaoyan [Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, 22 Hankou Road, Nanjing 210093, Jiangsu Province (China); Zhang, Dingding; Gao, Xin; Yu, Zhuang [Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China); Li, Kuanyu, E-mail: likuanyu@nju.edu.cn [Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, 22 Hankou Road, Nanjing 210093, Jiangsu Province (China); Hang, Chun-Hua, E-mail: hang_neurosurgery@163.com [Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province (China)

    2015-01-24

    Highlights: • Iron accumulation was involved in the acute phase following SAH. • Blockage of MCU could attenuate cellular iron accumulation following SAH. • Blockage of MCU could decrease ROS generation and improve cell energy supply following SAH. • Blockage of MCU could alleviate apoptosis and brain injury following SAH. - Abstract: Previous studies have shown that iron accumulation is involved in the pathogenesis of brain injury following subarachnoid hemorrhage (SAH) and chelation of iron reduced mortality and oxidative DNA damage. We previously reported that blockage of mitochondrial calcium uniporter (MCU) provided benefit in the early brain injury after experimental SAH. This study was undertaken to identify whether blockage of MCU could ameliorate iron accumulation-associated brain injury following SAH. Therefore, we used two reagents ruthenium red (RR) and spermine (Sper) to inhibit MCU. Sprague–Dawley (SD) rats were randomly divided into four groups including sham, SAH, SAH + RR, and SAH + Sper. Biochemical analysis and histological assays were performed. The results confirmed the iron accumulation in temporal lobe after SAH. Interestingly, blockage of MCU dramatically reduced the iron accumulation in this area. The mechanism was revealed that inhibition of MCU reversed the down-regulation of iron regulatory protein (IRP) 1/2 and increase of ferritin. Iron–sulfur cluster dependent-aconitase activity was partially conserved when MCU was blocked. In consistence with this and previous report, ROS levels were notably reduced and ATP supply was rescued; levels of cleaved caspase-3 dropped; and integrity of neurons in temporal lobe was protected. Taken together, our results indicated that blockage of MCU could alleviate iron accumulation and the associated injury following SAH. These findings suggest that the alteration of calcium and iron homeostasis be coupled and MCU be considered to be a therapeutic target for patients suffering from SAH.

  17. Laser accidents: Being Prepared

    Energy Technology Data Exchange (ETDEWEB)

    Barat, K

    2003-01-24

    The goal of the Laser Safety Officer and any laser safety program is to prevent a laser accident from occurring, in particular an injury to a person's eyes. Most laser safety courses talk about laser accidents, causes, and types of injury. The purpose of this presentation is to present a plan for safety offices and users to follow in case of accident or injury from laser radiation.

  18. [Accidents with the "paraglider"].

    Science.gov (United States)

    Lang, T H; Dengg, C; Gabl, M

    1988-09-01

    With a collective of 46 patients we show the details and kinds of accidents caused by paragliding. The base for the casuistry of the accidents was a questionnaire which was answered by most of the injured persons. These were questions about the theoretical and practical training, the course of the flight during the different phases, and the subjective point of view of the course of the accident. The patterns of the injuries showed a high incidence of injuries of the spinal column and high risks for the ankles. At the end, we give some advice how to prevent these accidents.

  19. Accidents (FARS) (National)

    Data.gov (United States)

    Department of Transportation — Accident - (1975-current): This data file (NTAD) contains information about crash characteristics and environmental conditions at the time of the crash. There is one...

  20. 大型汽轮发电机环形引线汽堵故障分析%Analysis of steam blockage faults of large turbogenerator circular lead

    Institute of Scientific and Technical Information of China (English)

    赵伟铎; 刘玉新; 杜博超; 崔淑梅

    2014-01-01

    大型汽轮发电机定子环形引线在不当的安装操作下容易引发汽堵故障堵塞水路,造成引线损毁甚至引发停机事故。该文针对具体事故案例,基于计算流体力学方法,建立引线及其冷却水的流固耦合共轭传热仿真模型,计算两起事故外接连通管错误接法下环形引线及其冷却水的温度场,分析温度特征与水路堵塞程度之间的对应关系。计算及分析结果表明,外接连通管错接后冷却水流量过低是导致汽堵故障的直接原因,汽堵发生后约半小时通风不良处的引线开始熔断。在此基础上,提出严格按照说明安装水路水管及加装温度与流量监测装置的预防和改进措施。%Steam blockage faults inside the circular lead of large turbogenerators, which initiated by some installation mistakes, will burn the lead and cause a non-normal shutdown accident. According to specific fault cases, the conjugate heat transfer model of the lead and its cooling water was constructed in this pa-per, based on the computational fluid dynamics. Thermal field of the lead and its water under a wrong re-turn pipe connection was calculated, and then the relationship between temperature characteristics and the degree of blockage was analyzed. The calculation and analysis results indicated that, the abnormal low flow rate caused by a wrong return pipe connection was the direct reason of steam blockage. The lead began to melt about 30 min after the formation of steam blockage. On this basis, this paper suggests a normative installation and extra thermal and flow monitor devices to prevent faults.

  1. Axillary Brachial Plexus Blockage in Treatment of Upper Extremity Ischemic Disorder in Critically Ill Patient: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    İlkay Ceylan

    2015-08-01

    Full Text Available Arterial catheterization, vasoactive agents, autonomic dysfunction and septic embolus may cause ischemia at distal ends of upper extremity in critically ill patients. Axillary brachial plexus blockage is highly reliable intervention when appropriate technique is used. Sympathetic blockage occurs after administration of local anesthetic drug and can resolve the circulatory disorder of extremity. We aimed to present two cases with ischemia of upper distal extremity that resolves after axillary brachial plexus blockage.

  2. TCM Treatment for 40 Cases of Rheumatoid Arthritis with Channel Blockage due to Yin Deficiency

    Institute of Scientific and Technical Information of China (English)

    杨维华; 欧阳剑虹; 朱克剑; 周慎; 彭志辉

    2003-01-01

    @@ To verify the therapeutic effects of the method of softening and lubricating the joints, and calming the endogenous wind in case of rheumatoidirthritis (RA) with the syndrome of channel blockage due to yin deficiency, 60 RA patients with the syndrome of channel blockage due to yin deficiency were randomly divided into a treatment group (40 cases) and a control group (20 cases) and treated respectively by the The result turned out to be that the effect in the treatment group was very satisfying. The treatment group obtained a better result in the accumulated points of syndrome and RA, morning rigidity of the joints, grip strength, 20m walking time and erythrocyte sedimentation rate (ESR) (P<0.01 or P<0.05). The above indicates that channel blockage due to yin deficiency is an important pathogenesis of RA, and calming the endogenous wind is a method of choice for treating RA.

  3. Effects of cooling channel blockage on fuel plate temperature in Tehran Research Reactor

    Institute of Scientific and Technical Information of China (English)

    TABBAKH Farshid

    2009-01-01

    In this study, the variation of the temperature distribution of the fuel plate in Tehran Research Reactor core was studied in case of coolant channels blockage. While the experimental method is not possible, both the analytical and simulation methods were used to obtain the more reliable data. The results show that one channel blockage will increase the fuel temperature to about 100%, but it does not lead to clad melt down still. With further calculation and simulation it is understood that if the coolant velocity drops to 90% of its nominal value, it may causes the clad melt-ing down. At least two channels with complete blockage even at the positions far from the core center can also melt down the clad.

  4. Design and Development of Vision Based Blockage Clearance Robot for Sewer Pipes

    Directory of Open Access Journals (Sweden)

    Krishna Prasad Nesaian

    2012-03-01

    Full Text Available Robotic technology is one of the advanced technologies, which is capable of completing tasks at situations where humans are unable to reach, see or survive. The underground sewer pipelines are the major tools for the transportation of effluent water. A lot of troubles caused by blockage in sewer pipe will lead to overflow of effluent water, sanitation problems. So robotic vehicle that is capable of traveling at underneath effluent water determining blockage using ultrasonic sensors and clearing by means of drilling mechanism is done. In addition to that wireless camera is fixed which acts as a robot vision by which we can monitor video and capture images using MATLAB tool. Thus in this project a prototype model of underground sewer pipe blockage clearance robot with drilling type will be developed

  5. Creativity: blockages and patterns of some employees at the Lawrence Livermore Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Moir, E.B.

    1978-06-01

    The kinds and quality of blockages to creativity are studied for two groups of employees, a group of peer-identified creative individuals and a group attending a career/life planning workshop. The employees from both groups represent a cross section of scientists/engineers, administrators, and technical support personnel and administrative support personnel. The design and results of the study are discussed, and some recommendations are made. It was found that the blockages of creative employees, as a group, were different from those of the self-selected, workshop group. Blockages reported by the peer-identified group were lack of time, office disharmony, and personal limitations, while those reported by the self-selected group were lack of time and fear of risk. (RWR)

  6. An arbitrarily short reply to Sheldon Smith on instantaneous velocities

    Science.gov (United States)

    Arntzenius, Frank

    The main issue is the question whether the standard calculus definition of velocities allows velocities to be part of the instantaneous states of objects. According to David Albert and I this is implausible, for if they were, then the instantaneous state of an object at a time t would in virtue of logic and definition alone impose a severe constraint on the history of instantaneous states of that object at other times. One can picture the constraint as follows: represent the position at time t by a dot on a piece of paper; represent the velocity at time t by an arrow that points away from that dot. The positions around time t can then be represented as a (parameterized) curve. The constraint now is that the curve must have the arrow as its tangent: as one gets close to t the curve must become parallel to the arrow (and must be parameterized at a rate that corresponds to the length of the arrow). This rules out many possible histories at times other than t. But surely an instantaneous state at time t ought not by logic and definition alone to constrain histories of instantaneous states at other times. Laws of nature and contingent relations can imply such constraints, but logic and definition should not. Compare: the intrinsic state at some spatial location x ought not by logic and definition alone to constrain the intrinsic states at other spatial locations. (For Lewis (1986) this is virtually a definition of "intrinsic".)

  7. Instantaneous Normal Modes and the Protein Glass Transition

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Roland [University of Tennessee, Knoxville (UTK); Krishnan, Marimuthu [ORNL; Daidone, Isabella [University of Heidelberg; Smith, Jeremy C [ORNL

    2009-01-01

    In the instantaneous normal mode method, normal mode analysis is performed at instantaneous configurations of a condensed-phase system, leading to modes with negative eigenvalues. These negative modes provide a means of characterizing local anharmonicities of the potential energy surface. Here, we apply instantaneous normal mode to analyze temperature-dependent diffusive dynamics in molecular dynamics simulations of a small protein (a scorpion toxin). Those characteristics of the negative modes are determined that correlate with the dynamical (or glass) transition behavior of the protein, as manifested as an increase in the gradient with T of the average atomic mean-square displacement at 220 K. The number of negative eigenvalues shows no transition with temperature. Further, although filtering the negative modes to retain only those with eigenvectors corresponding to double-well potentials does reveal a transition in the hydration water, again, no transition in the protein is seen. However, additional filtering of the protein double-well modes, so as to retain only those that, on energy minimization, escape to different regions of configurational space, finally leads to clear protein dynamical transition behavior. Partial minimization of instantaneous configurations is also found to remove nondiffusive imaginary modes. In summary, examination of the form of negative instantaneous normal modes is shown to furnish a physical picture of local diffusive dynamics accompanying the protein glass transition.

  8. Communication and industrial accidents

    NARCIS (Netherlands)

    As, Sicco van

    2001-01-01

    This paper deals with the influence of organizational communication on safety. Accidents are actually caused by individual mistakes. However the underlying causes of accidents are often organizational. As a link between these two levels - the organizational failures and mistakes - I suggest the conc

  9. Accidents - personal factors

    Energy Technology Data Exchange (ETDEWEB)

    Zaitsev, S.L.; Tsygankov, A.V.

    1982-03-01

    This paper evaluates influence of selected personal factors on accident rate in underground coal mines in the USSR. Investigations show that so-called organizational factors cause from 80 to 85% of all accidents. About 70% of the organizational factors is associated with social, personal and economic features of personnel. Selected results of the investigations carried out in Donbass mines are discussed. Causes of miner dissatisfaction are reviewed: 14% is caused by unsatisfactory working conditions, 21% by repeated machine failures, 16% by forced labor during days off, 14% by unsatisfactory material supply, 16% by hard physical labor, 19% by other reasons. About 25% of miners injured during work accidents are characterized as highly professionally qualified with automatic reactions, and about 41% by medium qualifications. About 60% of accidents is caused by miners with less than a 3 year period of service. About 15% of accidents occurs during the first month after a miner has returned from a leave. More than 30% of accidents occurs on the first work day after a day or days off. Distribution of accidents is also presented: 19% of accidents occurs during the first 2 hours of a shift, 36% from the second to the fourth hour, and 45% occurs after the fourth hour and before the shift ends.

  10. Accident investigation and analysis

    NARCIS (Netherlands)

    Kampen, J. van; Drupsteen, L.

    2013-01-01

    Many organisations and companies take extensive proactive measures to identify, evaluate and reduce occupational risks. However, despite these efforts things still go wrong and unintended events occur. After a major incident or accident, conducting an accident investigation is generally the next ste

  11. Empirical investigation of wind farm blockage effects in Horn Rev 1 offshore wind farm

    DEFF Research Database (Denmark)

    Mitraszewski, Karol; Hansen, Kurt Schaldemose; Nygaard, Nicolai;

    We present an empirical study of wind farm blockage effects based on Horns Rev 1 SCADA data. The mean inflow non-uniformities in wind speed are analyzed by calculating the mean power outputs of turbines located along the outer edges of the farm for different wind directions, wind speeds and stabi......We present an empirical study of wind farm blockage effects based on Horns Rev 1 SCADA data. The mean inflow non-uniformities in wind speed are analyzed by calculating the mean power outputs of turbines located along the outer edges of the farm for different wind directions, wind speeds...

  12. Ionic charge transport between blockages: Sodium cation conduction in freshly excised bulk brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Emin, David, E-mail: emin@unm.edu [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States); Akhtari, Massoud [Semple Institutes for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 (United States); Ellingson, B. M. [Department of Radiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 (United States); Mathern, G. W. [Department of Neurosurgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 (United States)

    2015-08-15

    We analyze the transient-dc and frequency-dependent electrical conductivities between blocking electrodes. We extend this analysis to measurements of ions’ transport in freshly excised bulk samples of human brain tissue whose complex cellular structure produces blockages. The associated ionic charge-carrier density and diffusivity are consistent with local values for sodium cations determined non-invasively in brain tissue by MRI (NMR) and diffusion-MRI (spin-echo NMR). The characteristic separation between blockages, about 450 microns, is very much shorter than that found for sodium-doped gel proxies for brain tissue, >1 cm.

  13. Flume Experiment on Stream Blockage by the Debris Flow From Tributary

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Stream blockage by the debris flow from tributary valleys is a common phenomenon in mountainous area,which takes place when large quantities of sediment transported by debris flow reaches a river channel causing its complete or partial blockage.The dam formed by debris flow may causes upstream and downstream flooding,and presents great threat to people and property.Because of the catastrophic influence on people and property,debris-flow dam has attracted many attentions from the researchers and local adm...

  14. INSTANTANEOUS KINEMATIC CHARACTERISTICS OF ASPECIAL 3-UPU PARALLEL MANIPULATOR

    Institute of Scientific and Technical Information of China (English)

    Li Shihua; Huang Zhen

    2005-01-01

    The instantaneous kinematics of a special 3-UPU parallel platform manipulator is discussed. First, the instantaneous motions of the 3-UPU manipulator in four kinds of positions and a special manipulator are studied by reciprocal screw theory. Then, the principal screws in one of four positions are obtained. It is shown that the moving platform has five degrees of freedom (DOF) in the initial position or after a translation along the z-axis; In the generic position, the mechanism only has three DOF, moreover the three DOF characteristics are different in different position. The instantaneous kinematic characteristics of alike 3-UPU mechanisms are very different in different position and special structure. The results presented are important to the use of alike 3-UPU parallel manipulator and contribute to the mechanism theory

  15. Popescu-Rohrlich correlations imply efficient instantaneous nonlocal quantum computation

    Science.gov (United States)

    Broadbent, Anne

    2016-08-01

    In instantaneous nonlocal quantum computation, two parties cooperate in order to perform a quantum computation on their joint inputs, while being restricted to a single round of simultaneous communication. Previous results showed that instantaneous nonlocal quantum computation is possible, at the cost of an exponential amount of prior shared entanglement (in the size of the input). Here, we show that a linear amount of entanglement suffices, (in the size of the computation), as long as the parties share nonlocal correlations as given by the Popescu-Rohrlich box. This means that communication is not required for efficient instantaneous nonlocal quantum computation. Exploiting the well-known relation to position-based cryptography, our result also implies the impossibility of secure position-based cryptography against adversaries with nonsignaling correlations. Furthermore, our construction establishes a quantum analog of the classical communication complexity collapse under nonsignaling correlations.

  16. Instantaneous oscillatory direction and phase for multivariate timeseries

    CERN Document Server

    Allefeld, Carsten

    2008-01-01

    This text describes a generalization of the analytic signal (Gabor, 1946) approach for the definition of instantaneous amplitude and phase to the case of multivariate signals. It was originally written as an appendix for another paper, where the determination of the locally dominant oscillatory direction (the instantaneous amplitude) described here is used as a preprocessing step for another kind of data analysis. The text is reproduced in a 'standalone' form because the procedure might prove useful in other contexts too, especially for the purpose of phase synchronization analysis (Rosenblum et al., 1996) between two (or more) multivariate sets of time series (Pascual-Marqui, 2007).

  17. Instantaneous normal mode analysis of melting of finite dust clusters.

    Science.gov (United States)

    Melzer, André; Schella, André; Schablinski, Jan; Block, Dietmar; Piel, Alexander

    2012-06-01

    The experimental melting transition of finite two-dimensional dust clusters in a dusty plasma is analyzed using the method of instantaneous normal modes. In the experiment, dust clusters are heated in a thermodynamic equilibrium from a solid to a liquid state using a four-axis laser manipulation system. The fluid properties of the dust cluster, such as the diffusion constant, are measured from the instantaneous normal mode analysis. Thereby, the phase transition of these finite clusters is approached from the liquid phase. From the diffusion constants, unique melting temperatures have been assigned to dust clusters of various sizes that very well reflect their dynamical stability properties.

  18. Instantaneous Rayleigh scattering from excitons localized in monolayer islands

    DEFF Research Database (Denmark)

    Langbein, Wolfgang; Leosson, Kristjan; Jensen, Jacob Riis;

    2000-01-01

    We show that the initial dynamics of Rayleigh scattering from excitons in quantum wells can be either instantaneous or delayed, depending on the exciton ensemble studied. For excitation of the entire exciton resonance, a finite rise time given by the inverse inhomogeneous broadening: of the exciton...... resonance is observed. Instead, when exciting only a subsystem of the exciton resonance, in our case excitons localized in quantum well regions of a specific monolayer thickness, the rise has an instantaneous component. This is due to the spatial nonuniformity of the initially excited exciton polarization...

  19. On Instantaneous Power Dissipation in Class B Amplifier

    Directory of Open Access Journals (Sweden)

    Hristo Zhivomirov

    2014-08-01

    Full Text Available The present paper describes the analysis of the instantaneous power dissipation by the two active components in a class B power amplifier. Attention is paid to restrictions of the instantaneous power dissipation relations in reference literature, and the consequences of their misuse. A new generalized equation that takes into account the power dissipated by the two active devices is proposed. The theoretical statement is substantiated by Matlab® numeric computation and visualization, Cadence OrCAD® simulations and measurements of a real-world audio power amplifier performed by NI USB-6211 measurement complex.

  20. Revised accident source terms for light-water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Soffer, L. [Nuclear Regulatory Commission, Washington, DC (United States)

    1995-02-01

    This paper presents revised accident source terms for light-water reactors incorporating the severe accident research insights gained in this area over the last 15 years. Current LWR reactor accident source terms used for licensing date from 1962 and are contained in Regulatory Guides 1.3 and 1.4. These specify that 100% of the core inventory of noble gases and 25% of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental iodine. These assumptions have strongly affected present nuclear air cleaning requirements by emphasizing rapid actuation of spray systems and filtration systems optimized to retain elemental iodine. A proposed revision of reactor accident source terms and some im implications for nuclear air cleaning requirements was presented at the 22nd DOE/NRC Nuclear Air Cleaning Conference. A draft report was issued by the NRC for comment in July 1992. Extensive comments were received, with the most significant comments involving (a) release fractions for both volatile and non-volatile species in the early in-vessel release phase, (b) gap release fractions of the noble gases, iodine and cesium, and (c) the timing and duration for the release phases. The final source term report is expected to be issued in late 1994. Although the revised source terms are intended primarily for future plants, current nuclear power plants may request use of revised accident source term insights as well in licensing. This paper emphasizes additional information obtained since the 22nd Conference, including studies on fission product removal mechanisms, results obtained from improved severe accident code calculations and resolution of major comments, and their impact upon the revised accident source terms. Revised accident source terms for both BWRS and PWRS are presented.

  1. Persistence of airline accidents.

    Science.gov (United States)

    Barros, Carlos Pestana; Faria, Joao Ricardo; Gil-Alana, Luis Alberiko

    2010-10-01

    This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non-stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long-run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation. © 2010 The Author(s). Journal compilation © Overseas Development Institute, 2010.

  2. Accidents with sulfuric acid

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2006-01-01

    Full Text Available Sulfuric acid is an important industrial and strategic raw material, the production of which is developing on all continents, in many factories in the world and with an annual production of over 160 million tons. On the other hand, the production, transport and usage are very dangerous and demand measures of precaution because the consequences could be catastrophic, and not only at the local level where the accident would happen. Accidents that have been publicly recorded during the last eighteen years (from 1988 till the beginning of 2006 are analyzed in this paper. It is very alarming data that, according to all the recorded accidents, over 1.6 million tons of sulfuric acid were exuded. Although water transport is the safest (only 16.38% of the total amount of accidents in that way 98.88% of the total amount of sulfuric acid was exuded into the environment. Human factor was the common factor in all the accidents, whether there was enough control of the production process, of reservoirs or transportation tanks or the transport was done by inadequate (old tanks, or the accidents arose from human factor (inadequate speed, lock of caution etc. The fact is that huge energy, sacrifice and courage were involved in the recovery from accidents where rescue teams and fire brigades showed great courage to prevent real environmental catastrophes and very often they lost their lives during the events. So, the phrase that sulfuric acid is a real "environmental bomb" has become clearer.

  3. Assessment of blockage effects on the wake characteristics and power of wind turbines

    DEFF Research Database (Denmark)

    Sarlak Chivaee, Hamid; Nishino, T.; Martínez-Tossas, L.A.;

    2016-01-01

    Large Eddy Simulations (LES) are performed in order to study the wake and power characteristics of a horizontal-axis wind turbine in a wind tunnel. Using an actuator line technique, the effect of wind tunnel blockage ratio (defined as the ratio of the rotor swept area to the tunnel cross...

  4. Wound-induced and bacteria-induced xylem blockage in roses, Astilbe and Viburnum

    NARCIS (Netherlands)

    Loubaud, M.; Doorn, van W.G.

    2004-01-01

    We previously concluded that the xylem blockage that prevents water uptake into several cut flowers is mainly due to the presence of bacteria, whilst in chrysanthemum and Bouvardia we observed a xylem occlusion that was mainly due to a wound-reaction of the plant. We have further tested which of the

  5. Preliminary Analysis for Flow Blockage of Plate Fuel using a Commercial CFD Code

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong-Pil; Park, Suki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    A plate-type fuel assembly is widely used in the research reactors in order to enhance power density. This type fuel assembly consists of a number of fuel plates, supporting plates, and narrow rectangular cooling channels between the fuel plates. Due to the narrow rectangular channels consisting of parallel plate fuels and side plates, the cooling channels are isolated from each other so that the cross flow between the channels are completely restricted. When blockage at the inlet of the channel occurs, therefore, the coolant flow through the blocked channel will be greatly reduced or completely interrupted. Accordingly, the blocked channel loses its own cooling capability. This event may cause initiation of nucleate boiling and two phase flow instability (FI) in the blocked channel. In recent years, CFD analyses of flow blockage of a research reactor have been performed by many researchers. The present study reports a 3-dimensional CFD simulation using two-phase model for flow blockage of two channels of a plate-type fuel assembly. The present result shows limited information since the simulation is working at the moment. However, the present study indicates that it is possible to predict a damage propagation of a plate-type fuel assembly due to the flow instability caused by flow blockage using a commercial CFD code.

  6. Blockage of mitochondrial calcium uniporter prevents iron accumulation in a model of experimental subarachnoid hemorrhage.

    Science.gov (United States)

    Yan, Huiying; Hao, Shuangying; Sun, Xiaoyan; Zhang, Dingding; Gao, Xin; Yu, Zhuang; Li, Kuanyu; Hang, Chun-Hua

    2015-01-24

    Previous studies have shown that iron accumulation is involved in the pathogenesis of brain injury following subarachnoid hemorrhage (SAH) and chelation of iron reduced mortality and oxidative DNA damage. We previously reported that blockage of mitochondrial calcium uniporter (MCU) provided benefit in the early brain injury after experimental SAH. This study was undertaken to identify whether blockage of MCU could ameliorate iron accumulation-associated brain injury following SAH. Therefore, we used two reagents ruthenium red (RR) and spermine (Sper) to inhibit MCU. Sprague-Dawley (SD) rats were randomly divided into four groups including sham, SAH, SAH+RR, and SAH+Sper. Biochemical analysis and histological assays were performed. The results confirmed the iron accumulation in temporal lobe after SAH. Interestingly, blockage of MCU dramatically reduced the iron accumulation in this area. The mechanism was revealed that inhibition of MCU reversed the down-regulation of iron regulatory protein (IRP) 1/2 and increase of ferritin. Iron-sulfur cluster dependent-aconitase activity was partially conserved when MCU was blocked. In consistence with this and previous report, ROS levels were notably reduced and ATP supply was rescued; levels of cleaved caspase-3 dropped; and integrity of neurons in temporal lobe was protected. Taken together, our results indicated that blockage of MCU could alleviate iron accumulation and the associated injury following SAH. These findings suggest that the alteration of calcium and iron homeostasis be coupled and MCU be considered to be a therapeutic target for patients suffering from SAH.

  7. Superluminal Physics and Instantaneous Physics as New Trends in Research

    Directory of Open Access Journals (Sweden)

    Smarandache F.

    2012-01-01

    Full Text Available In a similar way as passing from Euclidean Geometry to Non-Euclidean Geometry, we can pass from Subluminal Physics to Superluminal Physics, and further to Instantaneous Physics. In the lights of two consecutive successful CERN experiments with superlumi- nal particles in the Fall of 2011, we believe that these two new fields of research should begin developing.

  8. Voltage sag source location based on instantaneous energy detection

    DEFF Research Database (Denmark)

    Chen, Zhe; Xinzhou, Dong; Wei, Kong

    2007-01-01

    Voltage sag is the major power quality problem, which could disrupt the operation of sensitive equipment. This paper presents the applications of instantaneous energy direction for voltage sag source detection. Simulations have been performed to provide the analysis for system with distributed ge...... generation units. The studies show that the presented method can effectively detect the location of the voltage sag source....

  9. Preliminary validation of the MATRA-LMR-FB code for the flow blockage in a subassembly

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, H. Y.; Ha, K. S.; Kwon, Y. M.; Chang, W. P.; Lee, Y. B.; Heo, S

    2005-01-01

    To analyze the flow blockage in a subassembly of a Liquid Metal-cooled Reactor (LMR), the MATRA-LMR-FB code has been developed and validated for the existing experimental data. Compared to the MATRA-LMR code, which had been successfully applied for the core thermal-hydraulic design of KALIMER, the MATRA-LMR-FB code includes some advanced modeling features. Firstly, the Distributed Resistance Model (DRM), which enables a very accurate description of the effects of wire-wrap and blockage in a flow path, is developed for the MATRA-LMR-FB code. Secondly, the hybrid difference method is used to minimize the numerical diffusion especially at the low flow region such as recirculating wakes after blockage. In addition, the code is equipped with various turbulent mixing models to describe the active mixing due to the turbulent motions as accurate as possible. For the validation of the MATRA-LMR-FB code the ORNL THORS test and KOS 169-pin test are analyzed. Based on the analysis results for the temperature data, the accuracy of the code is evaluated quantitatively. The MATRA-LMR-FB code predicts very accurately the exit temperatures measured in the subassembly with wire-wrap. However, the predicted temperatures for the experiment with spacer grid show some deviations from the measured. To enhance the accuracy of the MATRA-LMR-FB for the flow path with grid spacers, it is suggested to improve the models for pressure loss due to spacer grid and the modeling method for blockage itself. The developed MATRA-LMR-FB code is evaluated to be applied to the flow blockage analysis of KALIMER-600 which adopts the wire-wrapped subassemblies.

  10. Traffic Accidents on Slippery Roads

    DEFF Research Database (Denmark)

    Fonnesbech, J. K.; Bolet, Lars

    2014-01-01

    Police registrations from 65 accidents on slippery roads in normally Danish winters have been studied. The study showed: • 1 accident per 100 km when using brine spread with nozzles • 2 accidents per 100 km when using pre wetted salt • 3 accidents per 100 km when using kombi spreaders The results...

  11. Boating Accident Statistics

    Data.gov (United States)

    Department of Homeland Security — Accident statistics available on the Coast Guard’s website by state, year, and one variable to obtain tables and/or graphs. Data from reports has been loaded for...

  12. Accident resistant transport container

    Science.gov (United States)

    Andersen, John A.; Cole, James K.

    1980-01-01

    The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

  13. The Fukushima accident; Accident nucleaire a Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Delbecq, D.

    2012-02-15

    The Fukushima accident is characterized by a sequence of natural disasters: earthquake and tsunamis that deprived simultaneously 3 reactors from cooling and electrical power for quite a long time. A series of hydrogen explosion has added to the mess. Experts agree to say that certainly nuclear fuel has melt to form corium in all 3 reactors. The accident has contaminated tens of thousand acres of land around the plant and has jeopardized local coastal fishery. The human toll is unexpectedly low: no direct casualty in the population but several suicides among the people that was forced to leave their home. 5 people from the plant staff died certainly from the consequences of the tsunami. (A.C.)

  14. Accidents with sulfuric acid

    OpenAIRE

    Rajković Miloš B.

    2006-01-01

    Sulfuric acid is an important industrial and strategic raw material, the production of which is developing on all continents, in many factories in the world and with an annual production of over 160 million tons. On the other hand, the production, transport and usage are very dangerous and demand measures of precaution because the consequences could be catastrophic, and not only at the local level where the accident would happen. Accidents that have been publicly recorded during the last eigh...

  15. Cyclical Fluctuations in Workplace Accidents

    OpenAIRE

    Boone, J.; J. C. VAN OURS

    2002-01-01

    This Paper presents a theory and an empirical investigation on cyclical fluctuations in workplace accidents. The theory is based on the idea that reporting an accident dents the reputation of a worker and raises the probability that he is fired. Therefore a country with a high or an increasing unemployment rate has a low (reported) workplace accident rate. The empirical investigation concerns workplace accidents in OECD countries. The analysis confirms that workplace accident rates are invers...

  16. Accidents in nuclear ships

    Energy Technology Data Exchange (ETDEWEB)

    Oelgaard, P.L. [Risoe National Lab., Roskilde (Denmark)]|[Technical Univ. of Denmark, Lyngby (Denmark)

    1996-12-01

    This report starts with a discussion of the types of nuclear vessels accidents, in particular accidents which involve the nuclear propulsion systems. Next available information on 61 reported nuclear ship events in considered. Of these 6 deals with U.S. ships, 54 with USSR ships and 1 with a French ship. The ships are in almost all cases nuclear submarines. Only events that involve the sinking of vessels, the nuclear propulsion plants, radiation exposures, fires/explosions, sea-water leaks into the submarines and sinking of vessels are considered. For each event a summary of available information is presented, and comments are added. In some cases the available information is not credible, and these events are neglected. This reduces the number of events to 5 U.S. events, 35 USSR/Russian events and 1 French event. A comparison is made between the reported Soviet accidents and information available on dumped and damaged Soviet naval reactors. It seems possible to obtain good correlation between the two types of events. An analysis is made of the accident and estimates are made of the accident probabilities which are found to be of the order of 10{sup -3} per ship reactor years. It if finally pointed out that the consequences of nuclear ship accidents are fairly local and does in no way not approach the magnitude of the Chernobyl accident. It is emphasized that some of the information on which this report is based, may not be correct. Consequently some of the results of the assessments made may not be correct. (au).

  17. Instantaneous power theory and applications to power conditioning

    CERN Document Server

    Akagi, Hirofumi; Aredes, Mauricio

    2017-01-01

    This new edition, written by a team of experts in the field, is fully updated with information on the latest electric power technology. The instantaneous power theory, or “the p-q theory,” makes clear the physical meaning of what instantaneous real and imaginary power is in a three-phase circuit. Moreover, it provides insight into how energy flows from a source to a load, or circulates between phases, in a three-phase circuit. This theory can be used in the design and understanding of FACTS (Flexible AC Transmission System) compensators. The book introduces many concepts in the field of active filtering that are unique to this edition. It provides a study tool for final year undergraduate students, graduate students and engineers dealing ith harmonic pollution problems, reactive power compensation or power quality in general.

  18. Analysis of nonlinear behavior of loudspeakers using the instantaneous frequency

    DEFF Research Database (Denmark)

    Huang, Hai; Jacobsen, Finn

    2003-01-01

    It is well know that the weakest link in a sound reproduction chain is the loudspeaker. The most significant effect on the sound quality is nonlinear distortion of loudspeakers. Many methods are applied to analyze the nonlinear distortion of loudspeakers. Almost all of the methods are based...... on the Fourier transform. In this work, a new method using the instantaneous frequency is introduced for describing and characterizing loudspeaker nonlinearities. First, numerical integration is applied to simulate the nonlinearities of loudspeakers caused by two nonlinear parameters, force factor and stiffness......, separately. Then, a practical loudspeaker is used in an experiment and its nonlinear characteristics are analyzed with the instantaneous frequency. The results provide a clear physical interpretation of the nonlinearities of loudspeakers and will be useful for understanding the nonlinear behavior...

  19. Instantaneous frequency measurement of dissipative soliton resonant light pulses.

    Science.gov (United States)

    Cuadrado-Laborde, C; Armas-Rivera, I; Carrascosa, A; Kuzin, E A; Beltrán-Pérez, G; Díez, A; Andrés, M V

    2016-12-15

    We measured the instantaneous frequency profile of two different dissipative soliton resonant (DSR) light pulses, the usual flat-top and less-common trapezoid-shaped light pulses. The DSR light pulses were provided by an ytterbium-doped polarization-maintaining fiber ring passively mode-locked laser using the adequately selected amount of net-normal dispersion. We confirmed that the DSR light pulses have a (moderately) low linear chirp across the pulse, except at the edges, where the chirp changes exponentially. This unique instantaneous frequency behavior can be succinctly resumed by the following parameters: linear chirp slope and leading and trailing chirp lifetimes. As the pump power increases, the linear chirp slope decreases, whereas the leading and trailing chirp lifetimes do not show an appreciable change. The results are compared with previous theoretical works.

  20. INSTANTANEOUS SHRINKING AND LOCALIZATION OF FUNCTIONS IN AND THEIR APPLICATIONS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The aim of this paper is to discuss the instantaneous shrinking and localization of the support of functions in Yλ (r, p, q, N) and their applications to some nonlinear parabolic equations including the porous medium equation ut = Δum - uq, m > 0, q > 0 and the p-Laplace equation ut = div(|▽u|p-2▽u) - uq, p > 1, q > 0. In particular, as an application of the results, the necessary and sufficient condition for the solutions of the above p-Laplace equation with nonnegative finite Borel measures as initial conditions to have the instantaneous shrinking property of the support is obtained. This is an answer to an open problem posed by R. Kersner and A. Shishkov.

  1. Experimental Investigation of Instantaneous Properties of Wave Slamming on the Plate

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The purpose of this paper is to investigate the instantaneous properties of wave slamming on the plate structure of an open structure. The advanced instantaneous measuring technique-Particle Image Velocimetry (PIV) is applied to acquire the instantaneous velocity field of wave slamming. From the cross-correlation analysis results of the images captured by the CCD camera, the flow fields of wave impacting on the structure are displayed visually, and the instantaneous whole-field fluid velocity vectors are obtained. The relation between the instantaneous peak impacting pressures and the instantaneous velocities of water particles is studied by probability analysis.

  2. Instantaneous GNSS attitude determination: A Monte Carlo sampling approach

    Science.gov (United States)

    Sun, Xiucong; Han, Chao; Chen, Pei

    2017-04-01

    A novel instantaneous GNSS ambiguity resolution approach which makes use of only single-frequency carrier phase measurements for ultra-short baseline attitude determination is proposed. The Monte Carlo sampling method is employed to obtain the probability density function of ambiguities from a quaternion-based GNSS-attitude model and the LAMBDA method strengthened with a screening mechanism is then utilized to fix the integer values. Experimental results show that 100% success rate could be achieved for ultra-short baselines.

  3. Probability density functions of instantaneous Stokes parameters on weak scattering

    Science.gov (United States)

    Chen, Xi; Korotkova, Olga

    2017-10-01

    The single-point probability density functions (PDF) of the instantaneous Stokes parameters of a polarized plane-wave light field scattered from a three-dimensional, statistically stationary, weak medium with Gaussian statistics and Gaussian correlation function have been studied for the first time. Apart from the scattering geometry the PDF distributions of the scattered light have been related to the illumination's polarization state and the correlation properties of the medium.

  4. Instantaneous Bethe-Salpeter Kernel for the Lightest Pseudoscalar Mesons

    CERN Document Server

    Lucha, Wolfgang

    2016-01-01

    Starting from a phenomenologically successful, numerical solution of the Dyson-Schwinger equation that governs the quark propagator, we reconstruct in detail the interaction kernel that has to enter the instantaneous approximation to the Bethe-Salpeter equation to allow us to describe the lightest pseudoscalar mesons as quark-antiquark bound states exhibiting the (almost) masslessness necessary for them to be interpretable as the (pseudo) Goldstone bosons related to the spontaneous chiral symmetry breaking of quantum chromodynamics.

  5. Instantaneous Wavelet Energetic Transfers between Atmospheric Blocking and Local Eddies.

    Science.gov (United States)

    Fournier, Aimé

    2005-07-01

    A new wavelet energetics technique, based on best-shift orthonormal wavelet analysis (OWA) of an instantaneous synoptic map, is constructed for diagnosing nonlinear kinetic energy (KE) transfers in five observed blocking cases. At least 90% of the longitudinal variance of time and latitude band mean 50-kPa geopotential is reconstructed by only two wavelets using best shift. This superior efficiency to the standard OWAs persists for time-evolving structures. The cases comprise two categories, respectively dominated by zonal-wavenumber sets {1} and {1, 2}. Further OWA of instantaneous residual nonblocking structures, combined with new “nearness” criteria, yields three more orthogonal components, representing smaller-scale eddies near the block (upstream and downstream) and distant structures. This decomposition fulfills a vision expressed to the author by Saltzman. Such a decomposition is not obtainable by simple Fourier analysis.Eddy patterns apparent in the components' contours suggest inferring geostrophic energetic interactions, but the component Rossby numbers may be too large to support the inference. However, a new result enabled by this method is the instantaneous attribution of blocking strain-field effects to particular energetically interactive eddies, consistent with Shutts' hypothesis. Such attribution was only possible before in simplified models or in a time-average sense. In four of five blocks, the upstream eddies feed KE to the block, which in turn, in three of four cases, transmits KE to the downstream eddies. The small case size precludes statistically significant conclusions. The appendixes link low-order blocking structure and dynamics to some wavelet design principles and propose a new interaction diagnosis, similar to E-vector analysis, but instantaneous.

  6. Instantaneous Point, Line, and Plane Motions Using a Clifford Algebra

    Institute of Scientific and Technical Information of China (English)

    Kwun-Lon Ting; Yi Zhang

    2004-01-01

    The motions of points, lines, and planes, embedded in a rigid body are expressed in a unified algebraic framework using a Clifford algebra. A Clifford algebra based displacement operator is addressed and its higher derivatives from which the coordinate-independent characteristic numbers with simple geometric meaning are defined. Because of the coordinate independent feature, no tedious coordinate transformation typically found in the conventional instantaneous invariants methods is needed.

  7. INSTANTANEOUS AND INTEGRAL POWER EQUATIONS OF NONSINUSOIDAL 3-PHASE PROCESSES

    Directory of Open Access Journals (Sweden)

    Iu.A. Sirotin

    2016-03-01

    Full Text Available Purpose. To identify the mathematical relationship between the instantaneous powers (classical and vectorial and integral powers in non-sinusoidal mode and to get complex form of instantaneous powers in 3-phase 4-wire power supply in terms of the spectral approach. Methodology. We have applied the vector approach with one voice allows you to analyze the energy characteristics of 3-phase power supply circuits (for 4-wire and 3-wire circuits in sinusoidal and non–sinusoidal mode, both the time domain and frequency domain. We have used 3-dimensional representation of the energy waveforms with the complex multi-dimensional Fourier series. Results. For 4-wire network with a non-sinusoidal (regardless of their symmetry processes, we have developed the mathematical model one-dimensional representations of the complex form for the active (scalar instantaneous power (IP and 3-dimensional form (inactive vectorial IP. It is possible to obtain two dual integral power equations for complex scalar and vector integrated power of non-sinusoidal modes. The power equations generalize generalizes the equations of sinusoidal modes for 4-wire network. Originality. In addition to the classification of energy local regimes in the time domain for the first time we spent the classification of non-sinusoidal modes in the spectral region and showed the value and importance of the classification of regimes based on the instantaneous powers. Practical value. The practical value the obtained equations is the possibility of their use for improving the quality of electricity supply and the quality electricity consumption.

  8. Voltage Sag Source Location Based on Instantaneous Energy Detection

    DEFF Research Database (Denmark)

    Chen, Zhe; Kong, Wei; Dong, Xinzhou

    2008-01-01

    Voltage sag is a major power quality problem, which could disrupt the operation of voltage-sensitive equipment. This paper presents the method based on variation components-based instantaneous energy for voltage sag source detection. Simulations have been performed to provide the thorough analysi...... for system with distributed generation units. The studies show that the presented method can effectively detect the location of voltage sag source....

  9. Range-instantaneous Doppler imaging of inverse synthetic aperture sonar

    Institute of Scientific and Technical Information of China (English)

    XU Jia; JIANG Xingzhou; TANG Jingsong

    2003-01-01

    Because the existing range-Doppler algorithm in inverse synthetic aperture sonar (ISAS) is based on target model of uniform motion, it may be invalidated for maneuvering targets due to the time-varying changes of both individual scatter′s Doppler and imaging projection plane. To resolve the problem, a new range-instantaneous Doppler imaging method is proposed for imaging maneuvering targets based on time-frequency analysis. The proposed approach is verified using real underwater acoustic data.

  10. Automatic first-break picking using the instantaneous traveltime attribute

    KAUST Repository

    Saragiotis, Christos

    2012-01-01

    Picking the first breaks is an important step in seismic processing. The large volume of the seismic data calls for automatic and objective picking. We introduce a new automatic first-break picker, which uses specifically designed time windows and an iterative procedure based on the instantaneous traveltime attribute. The method is fast as it only uses a few FFT\\'s per trace. We demonstrate the effectiveness of this automatic method by applying it on real test data.

  11. Smooth and fast versus instantaneous quenches in quantum field theory

    CERN Document Server

    Das, Sumit R; Myers, Robert C

    2015-01-01

    We examine in detail the relationship between smooth fast quantum quenches, characterized by a time scale $\\delta t$, and instantaneous quenches, within the framework of exactly solvable mass quenches in free scalar field theory. We study UV finite quantities like correlators at finite spatial distances and the excess energy produced above the final ground state energy. We show that at late times and large distances (compared to the quench time scale) the correlator approaches the instantaneous quench correlator. At early times, we find that for small spatial separation and small $\\delta t$, the correlator scales universally with $\\delta t$, exactly as in the scaling of renormalized one point functions found in earlier work. At larger separation, the dependence on $\\delta t$ drops out. The excess energy also scales in a universal fashion: in the $m\\delta t \\rightarrow0$ limit it is finite for $d \\leq 3$ and agrees with the instantaneous quench, while it is divergent in higher dimensions. We argue that similar...

  12. Decay ratio estimation using the instantaneous autocorrelation function

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Fernandez, Jose E.; Prieto-Guerrero, Alfonso [Division de Ciencias Basicas e Ingenieria, Universidad Autonoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186 Col. Vicentina, Mexico, D.F. 09340 (Mexico); Espinosa-Paredes, Gilberto, E-mail: gepe@xanum.uam.m [Division de Ciencias Basicas e Ingenieria, Universidad Autonoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186 Col. Vicentina, Mexico, D.F. 09340 (Mexico)

    2010-10-15

    Research highlights: {yields} The ACEDR measure reflects major long-term changes in BWR stability. {yields} Synthetic and real neutronic signals were used to validate the method. {yields} The method was tested on the Laguna Verde Unit 1. {yields} The method was tested in three events reported in the Ringhals stability benchmark. {yields} The ACEDR measure exhibits a series of interesting properties. {yields} The ACEDR can detect long signal trends. - Abstract: In this paper a novel method based on the instantaneous autocorrelation function (IACF) is proposed to determine the time evolution of the linear stability parameters of a boiling water reactor (BWR) using neutronic noise signals. The IACF allow us to track the instantaneous signal envelope changes in time by defining an envelope instantaneous decay ratio (EIDR) which is used as a measure of local stability. In order to account for long-term changes in BWR stability, the accumulated envelope-based decay ratio (ACEDR) measure is introduced as the product of the local EIDRs. As it is shown in this paper, the ACEDR measure clearly reflects major long-term changes in BWR stability. Last the natural resonant frequency of the nuclear reactor is estimated from the Fourier transform of a weighted version of the IACF called generalized local autocorrelation function (GLACF). In order to validate our method, synthetic and real neutronic signals were used. The methodology was tested on the Laguna Verde Unit 1 and three events reported in the Ringhals stability benchmark.

  13. Maximum Inhibition of Breast Cancer/Stem Cell Growth by Concomitant Blockage of Key Receptors

    Directory of Open Access Journals (Sweden)

    Mossa Gardaneh

    2012-01-01

    Full Text Available The blockage of cancer cell growth and division is the prime objective in clinical cancer therapy both at early stages and for inhibition of minimal residual disease and relapse. The failure of conventional therapies in treating breast cancer (BC has prompted dissection of signalling pathways involved in BC cell growth and characterisation of cellular receptors. Specific sets of membrane-bound receptors promote disarrayed self-renewal of BC stem cells and deregulated BC cell proliferation. Individual blockage of each receptor promotes only incomplete inhibition of BC cell growth and partial regression of metastasis. Such monotherapies are based on either chemotherapy or monoclonal antibodies. However, they do not provide long-lasting benefits and are further compromised by increasing resistance the cancer cells acquire against therapeutic agents, by their evasion of receptor blockage and by adoption of alternative growth routes that are induced by cross-talks between key receptors. On the other hand, dual targeting approaches, including receptor blockage combined with chemotherapy, produce prolonged overall survival but, nevertheless, complicate treatment by inducing side effects. Based on the complex nature of BC, combined targeted strategies that potentially confer maximum coverage for treatment cannot be effective without overcoming drug resistance initiated and further induced by inter-receptor communications. This implies that a comprehensive strategy based on concomitant inhibition of key receptors could provide an ultimate solution for effective treatment of aggressive types of BC. Such a strategy would likely be capable of targeting breast tumour cells and BC stem cells alike eventually forcing the cancer to regress.

  14. In vitro maturation and embryo development of bovine oocytes after meiosis blockage with MPF inhibitors

    Directory of Open Access Journals (Sweden)

    Mariana Groke Marques

    2011-12-01

    Full Text Available This study evaluated the bovine oocyte maturation and embryo development after in vitro fertilization. The maturation of the oocytes was blocked using Butyrolactone I and Roscovitine using pre-maturation medium supplemented with fetal calf serum (FCS. The ocytes were divided in four groups: Control 0 hour, Control (24 hours of maturation, Roscovitine (maturation blockage with 50mM Roscovitine during 24 hours followed by 24 hours of maturation, and Butyrolactone I (maturation blockage with 150mM Butyrolactone I during 24 hours followed by 24 hours of maturation. The oocytes were fixed and stained with aceto orcein to evaluate the nuclear maturation. After the maturation period, the remaining oocytes of the Control group, Roscovitine, and Butyrolactone I were fertilized in vitro. Embryo development was assessed by the cleavage rate (D3 and blastocysts formation (D7. The Butyrolactone I group had similar rates of germinal vesical stage oocytes during blockage, and Metaphase 2 after maturation, comparing to Control group at 0 hour and Control group, respectively. On the other hand, the Roscovitine group had lower rates of vesical stage oocytes during blockage, and Metaphase 2 after maturation comparing to Control groups. After in vitro fertilization, higher rates of cleavage were observed in Control and Butyrolactone I groups. For the blastocyst formation rate, the Control group showed better results than Roscovitine group. In summary, Butyrolactone I group had similar results to the Control group, and for this reason, is suitable for pre-maturation of bovine oocytes using FCS. In contrast, Roscovitine group had lower oocyte maturation and embryo development.

  15. An investigation into the roles of histamine receptors in the control of human nasal blockage

    OpenAIRE

    Taylor-Clark, T. E.

    2004-01-01

    Allergic rhinitis is an allergic disease of the nose and, in sensitized individuals, is caused by inhaled innocuous particles such as pollen and house dust mite faeces. Allergen binds IgE on the surface of nasal mast cells, causing mast cell activation and degranulation, resulting in the release of inflammatory substances that are responsible for the symptoms of allergic rhinitis — sneezing, rhinorrhea, pruritus and nasal blockage. In this thesis, the mechanisms by which histamine, a mast cel...

  16. Who by accident? The social morphology of car accidents.

    Science.gov (United States)

    Factor, Roni; Yair, Gad; Mahalel, David

    2010-09-01

    Prior studies in the sociology of accidents have shown that different social groups have different rates of accident involvement. This study extends those studies by implementing Bourdieu's relational perspective of social space to systematically explore the homology between drivers' social characteristics and their involvement in specific types of motor vehicle accident. Using a large database that merges official Israeli road-accident records with socioeconomic data from two censuses, this research maps the social order of road accidents through multiple correspondence analysis. Extending prior studies, the results show that different social groups indeed tend to be involved in motor vehicle accidents of different types and severity. For example, we find that drivers from low socioeconomic backgrounds are overinvolved in severe accidents with fatal outcomes. The new findings reported here shed light on the social regularity of road accidents and expose new facets in the social organization of death. © 2010 Society for Risk Analysis.

  17. Access Time of Emergency Vehicles Under the Condition of Street Blockages after a Large Earthquake

    Science.gov (United States)

    Hirokawa, N.; Osaragi, T.

    2016-09-01

    The previous studies have been carried out on accessibility in daily life. However it is an important issue to improve the accessibility of emergency vehicles after a large earthquake. In this paper, we analyzed the accessibility of firefighters by using a microscopic simulation model immediately after a large earthquake. More specifically, we constructed the simulation model, which describes the property damage, such as collapsed buildings, street blockages, outbreaks of fires, and fire spreading, and the movement of firefighters from fire stations to the locations of fires in a large-scale earthquake. Using this model, we analyzed the influence of the street-blockage on the access time of firefighters. In case streets are blocked according to property damage simulation, the result showed the average access time is more than 10 minutes in the outskirts of the 23 wards of Tokyo, and there are some firefighters arrive over 20 minutes at most. Additionally, we focused on the alternative routes and proposed that volunteers collect information on street blockages to improve the accessibility of firefighters. Finally we demonstrated that access time of firefighters can be reduced to the same level as the case no streets were blocked if 0.3% of residents collected information in 10 minutes.

  18. CCR5 blockage by maraviroc induces cytotoxic and apoptotic effects in colorectal cancer cells.

    Science.gov (United States)

    Pervaiz, Asim; Ansari, Shariq; Berger, Martin R; Adwan, Hassan

    2015-05-01

    Alterations in the expression of C-C chemokine receptor type 5 (CCR5 or CD195) have been correlated with disease progression in different cancers. Recently, a few investigations have reported the blockage of this receptor by an antagonist (maraviroc) and its antineoplastic effects on tumor cell growth. However, little is known about the mechanistic reasons behind these antineoplastic effects of CCR5 blockage by maraviroc. In this study, we blocked the CCR5 receptor by maraviroc in SW480 and SW620 colorectal cancer cells to study the resulting changes in biological properties and related pathways. This blockage induced significantly reduced proliferation and a profound arrest in G1 phase of the cell cycle. Concomitantly, maraviroc caused significant signs of apoptosis at morphological level. Significant modulation of multiple apoptosis-relevant genes was also noticed at mRNA levels. In addition, we found remarkable increases in cleaved caspases at protein level. These modulations led us to propose a signaling pathway for the observed apoptotic effects. In conclusion, blocking the CCR5 by maraviroc induces significant cytotoxic and apoptotic effects in colorectal cancer cells. Thus, maraviroc can be considered a model compound, which may foster the development of further CCR5 antagonists to be used for the treatment of colorectal cancer.

  19. RELATIONSHIP OF CONCHA BULLOSA WITH OSTEOMEATAL UNI T BLOCKAGE. TOMOGRAPHIC STUDY IN 200 PATIENTS.

    Directory of Open Access Journals (Sweden)

    Shrikrishna

    2013-05-01

    Full Text Available ABSTRACT: - OBJECTIVE : To determine the prevalence of concha bullosa in patients suffering from chronic rhinosinusitis and to examine its possible relationship to osteomeatal unit blockage, the latter being a precursor for rhinosinusitis. DESIGN : A prospective study of prevalence of concha bullosa and blockage of ipsilateral osteomeatal uni t was done on 200 computed tomography scans of patients with chronic rhinosinusitis. RESULTS : Of the 200 CT scans with Chronic Rhinosinusitis, the incidence of concha bullosa 34%. Of this, 31 ca ses (45.6% were of extensive type, 21 cases (30.9% were of bulbous type and 16 cases (23.5% w ere of lamellar type. There was no statistically significant association between any t ype of concha bullosa with ipsilateral osteomeatal unit block either in right side or left side. CONCLUSION: There is no statistically significant relationship between presence of concha bullosa and ipsilateral osteomeatal unit blockage that leads to block in drainage of anterior group of par anasal sinuses. There is a significantly higher occurrence of the ostium of bulbous type of concha bullosa opening into the hiatus semilunaris.

  20. Critical role of blockage ratio for flame acceleration in channels with tightly spaced obstacles

    Science.gov (United States)

    Ugarte, Orlando J.; Bychkov, Vitaly; Sadek, Jad; Valiev, Damir; Akkerman, V'yacheslav

    2016-09-01

    A conceptually laminar mechanism of extremely fast flame acceleration in obstructed channels, identified by Bychkov et al. ["Physical mechanism of ultrafast flame acceleration," Phys. Rev. Lett. 101, 164501 (2008)], is further studied by means of analytical endeavors and computational simulations of compressible hydrodynamic and combustion equations. Specifically, it is shown how the obstacles length, distance between the obstacles, channel width, and thermal boundary conditions at the walls modify flame propagation through a comb-shaped array of parallel thin obstacles. Adiabatic and isothermal (cold and preheated) side walls are considered, obtaining minor difference between these cases, which opposes the unobstructed channel case, where adiabatic and isothermal walls provide qualitatively different regimes of flame propagation. Variations of the obstructed channel width also provide a minor influence on flame propagation, justifying a scale-invariant nature of this acceleration mechanism. In contrast, the spacing between obstacles has a significant role, although it is weaker than that of the blockage ratio (defined as the fraction of the channel blocked by obstacles), which is the key parameter of the problem. Evolution of the burning velocity and the dependence of the flame acceleration rate on the blockage ratio are quantified. The critical blockage ratio, providing the limitations for the acceleration mechanism in channels with comb-shaped obstacles array, is found analytically and numerically, with good agreement between both approaches. Additionally, this comb-shaped obstacles-driven acceleration is compared to finger flame acceleration and to that produced by wall friction.

  1. Compressive Sensing for Blockage Detection in Vehicular Millimeter Wave Antenna Arrays

    KAUST Repository

    Eltayeb, Mohammed E.

    2017-02-07

    The radiation pattern of an antenna array depends on the excitation weights and the geometry of the array. Due to mobility, some vehicular antenna elements might be subjected to full or partial blockages from a plethora of particles like dirt, salt, ice, and water droplets. These particles cause absorption and scattering to the signal incident on the array, and as a result, change the array geometry. This distorts the radiation pattern of the array mostly with an increase in the sidelobe level and decrease in gain. In this paper, we propose a blockage detection technique for millimeter wave vehicular antenna arrays that jointly estimates the locations of the blocked antennas and the attenuation and phase-shifts that result from the suspended particles. The proposed technique does not require the antenna array to be physically removed from the vehicle and permits real-time array diagnosis. Numerical results show that the proposed technique provides satisfactory results in terms of block detection with low detection time provided that the number of blockages is small compared to the array size.

  2. Comparison of data correction methods for blockage effects in semispan wing model testing

    Directory of Open Access Journals (Sweden)

    Haque Anwar U

    2016-01-01

    Full Text Available Wing alone models are usually tested in wind tunnels for aerospace applications like aircraft and hybrid buoyant aircraft. Raw data obtained from such testing is subject to different corrections such as wall interference, blockage, offset in angle of attack, dynamic pressure and free stream velocity etc. Since the flow is constrained by wind tunnel walls, therefore special emphasis is required to deliberate the limitation of correction methods for blockage correction. In the present research work, different aspects of existing correction methods are explored with the help of an example of a straight semi-span wing. Based on the results of analytical relationships of standard methods, it was found that although multiple variables are involved in the standard methods for the estimation of blockage, they are based on linearized flow theory such as source sink method and potential flow assumption etc, which have intrinsic limitations. Based on the computed and estimated experimental results, it is recommended to obtain the corrections by adding the difference in results of solid walls and far-field condition in the wind tunnel data. Computational Fluid Dynamics technique is found to be useful to determine the correction factors for a wing installed at zero spacer height/gap, with and without the tunnel wall.

  3. Comparison of data correction methods for blockage effects in semispan wing model testing

    Science.gov (United States)

    Haque, Anwar U.; Asrar, Waqar; Omar, Ashraf A.; Sulaeman, Erwin; J. S Ali, Mohamed

    2016-03-01

    Wing alone models are usually tested in wind tunnels for aerospace applications like aircraft and hybrid buoyant aircraft. Raw data obtained from such testing is subject to different corrections such as wall interference, blockage, offset in angle of attack, dynamic pressure and free stream velocity etc. Since the flow is constrained by wind tunnel walls, therefore special emphasis is required to deliberate the limitation of correction methods for blockage correction. In the present research work, different aspects of existing correction methods are explored with the help of an example of a straight semi-span wing. Based on the results of analytical relationships of standard methods, it was found that although multiple variables are involved in the standard methods for the estimation of blockage, they are based on linearized flow theory such as source sink method and potential flow assumption etc, which have intrinsic limitations. Based on the computed and estimated experimental results, it is recommended to obtain the corrections by adding the difference in results of solid walls and far-field condition in the wind tunnel data. Computational Fluid Dynamics technique is found to be useful to determine the correction factors for a wing installed at zero spacer height/gap, with and without the tunnel wall.

  4. ALICE Injected Beam Accidents

    CERN Document Server

    Appleby, R B

    2009-01-01

    The ALICE (point 2) interaction region is sensitive to beam orbit errors arising from magnet setting errors on injection. In this report, beam accident scenarios under injection for ALICE are described, focusing on ultra- fast error injection scenarios for the interaction straight correctors and dipoles. Beam 1 and beam 2 accident scenarios are considered, where the errors can lead to beam orbits striking the ALICE vacuum chamber or elements of the machine. The required thresholds for magnet current interlocks are calculated to avoid machine and detector risk.

  5. LHCb Injected Beam Accidents

    CERN Document Server

    Appleby, R B

    2009-01-01

    The LHCb (point 8) interaction region is sensitive to beam orbit errors arising from magnet setting errors on injection. In this report, beam accident scenarios under injection for LHCb are described, focusing on ultra- fast error injection scenarios for the interaction straight correctors and dipoles. Beam 1 and beam 2 accident scenarios are considered, where the errors can lead to beam orbits striking the LHCb vacuum chamber or elements of the machine. The required thresholds for magnet current interlocks are calculated to avoid machine and detector risk.

  6. Model for the determination of instantaneous values of the velocity, instantaneous, and average acceleration for 100-m sprinters.

    Science.gov (United States)

    JanjiĆ, NataŠa J; Kapor, Darko V; Doder, Dragan V; Doder, Radoslava Z; SaviĆ, Biljana V

    2014-12-01

    Temporal patterns of running velocity is of profound interest for coaches and researchers involved in sprint racing. In this study, we applied a nonhomogeneous differential equation for the motion with resistance force proportional to the velocity for the determination of the instantaneous velocity and instantaneous and average acceleration in the sprinter discipline at 100 m. Results obtained for the instantaneous velocity in this study using the presented model indicate good agreement with values measured directly, which is a good verification of the proposed procedure. To perform a comprehensive analysis of the applicability of the results obtained, the harmonic canon of running for the 100-m sprint discipline was formed. Using the data obtained by the measurement of split times for segments of 100-m run of the sprinters K. Lewis (1988), M. Green (2001), and U. Bolt (2009), the method described yielded results that enable comparative analysis of the kinematical parameters for each sprinter. Further treatment allowed the derivation of the ideal harmonic velocity canon of running, which can be helpful to any coach in evaluating the results achieved at particular distances in this and other disciplines. The method described can be applied for the analysis of any race.

  7. 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.

  8. Statistical analysis and definition of blockages-prediction formulae for the wastewater network of Oslo by evolutionary computing.

    Science.gov (United States)

    Ugarelli, Rita; Kristensen, Stig Morten; Røstum, Jon; Saegrov, Sveinung; Di Federico, Vittorio

    2009-01-01

    Oslo Vann og Avløpsetaten (Oslo VAV)-the water/wastewater utility in the Norwegian capital city of Oslo-is assessing future strategies for selection of most reliable materials for wastewater networks, taking into account not only material technical performance but also material performance, regarding operational condition of the system.The research project undertaken by SINTEF Group, the largest research organisation in Scandinavia, NTNU (Norges Teknisk-Naturvitenskapelige Universitet) and Oslo VAV adopts several approaches to understand reasons for failures that may impact flow capacity, by analysing historical data for blockages in Oslo.The aim of the study was to understand whether there is a relationship between the performance of the pipeline and a number of specific attributes such as age, material, diameter, to name a few. This paper presents the characteristics of the data set available and discusses the results obtained by performing two different approaches: a traditional statistical analysis by segregating the pipes into classes, each of which with the same explanatory variables, and a Evolutionary Polynomial Regression model (EPR), developed by Technical University of Bari and University of Exeter, to identify possible influence of pipe's attributes on the total amount of predicted blockages in a period of time.Starting from a detailed analysis of the available data for the blockage events, the most important variables are identified and a classification scheme is adopted.From the statistical analysis, it can be stated that age, size and function do seem to have a marked influence on the proneness of a pipeline to blockages, but, for the reduced sample available, it is difficult to say which variable it is more influencing. If we look at total number of blockages the oldest class seems to be the most prone to blockages, but looking at blockage rates (number of blockages per km per year), then it is the youngest class showing the highest blockage rate

  9. Lessons learned from accidents investigations

    Energy Technology Data Exchange (ETDEWEB)

    Zuniga-Bello, P. [Consejo Nacional de Ciencia y Tecnologia (CONACYT), Mexico City (Mexico); Croft, J. [National Radiological Protection Board (United Kingdom); Glenn, J

    1997-12-31

    Accidents from three main practices: medical applications, industrial radiography and industrial irradiators are used to illustrate some common causes of accidents and the main lessons to be learned. A brief description of some of these accidents is given. Lessons learned from the described accidents are approached by subjects covering: safety culture, quality assurance, human factors, good engineering practice, defence in depth, security of sources, safety assessment and monitoring and verification compliance. (author)

  10. Axillary Brachial Plexus Blockage in Treatment of Upper Extremity Ischemic Disorder in Critically Ill Patient: A Report of Two Cases

    OpenAIRE

    İlkay Ceylan; Nermin Kelebek Girgin; Mehmet Ali Kopan; Alp Gurbet

    2015-01-01

    Arterial catheterization, vasoactive agents, autonomic dysfunction and septic embolus may cause ischemia at distal ends of upper extremity in critically ill patients. Axillary brachial plexus blockage is highly reliable intervention when appropriate technique is used. Sympathetic blockage occurs after administration of local anesthetic drug and can resolve the circulatory disorder of extremity. We aimed to present two cases with ischemia of upper distal extremity that resolves after axillary ...

  11. Authority structure and industrial accidents

    NARCIS (Netherlands)

    As, Sicco van

    2001-01-01

    This paper deals with the influence of organizational characteristics on safety. Accidents are actually caused by individual mistakes. However the underlying causes of accidents are often organizational. The general hypothesis is that the authority structure is a main cause of accident-proneness

  12. Emission factors for passenger cars: application of instantaneous emission modeling

    Science.gov (United States)

    de Haan, Peter; Keller, Mario

    This paper discusses the use of 'instantaneous' high-resolution (1 Hz) emission data for the estimation of passenger car emissions during real-world driving. Extensive measurements of 20 EURO-I gasoline passenger cars have been used to predict emission factors for standard (i.e. legislative) as well as non-standard (i.e. real-world) driving patterns. It is shown that emission level predictions based upon chassis dynamometer tests over standard driving cycles significantly underestimate emission levels during real-world driving. The emission characteristics of modern passenger cars equipped with a three-way catalytic converter are a low, basic emission level on the one hand, and frequent emission 'peaks' on the other. For real-world driving, up to one-half of the entire emission can be emitted during these short-lasting peaks. Their frequency depends on various factors, including the level of 'dynamics' (speed variation) of the driving pattern. Because of this, the use of average speed as the only parameter to characterize emissions over a specific driving pattern is not sufficient. The instantaneous emissions approach uses an additional parameter representing engine load in order to resolve the differences between driving patterns with comparable average speeds but different levels of 'dynamics'. The paper includes an investigation of different statistical indicators and discusses methods to further improve the prediction capability of the instantaneous emission approach. The fundamental differences in emission-reduction strategies between different car manufacturers make the task of constructing a model valid for all catalyst passenger cars seemingly impossible, if the model is required to predict both fleet-averaged emission levels and emission factors for driving patterns of short duration for individual vehicles simultaneously.

  13. Differential Entropy and the Statistics of Instantaneous Failure.

    Science.gov (United States)

    2014-09-26

    1 A)AISB 047 DIFFERENIIAL ENTROPY AND THE STATISTICS OF i/IA E INSIANTANEOUS FAILURE(UI NAVAL RESEARCH LAB WASHINGTON N F D C A K RAJAOOPAL ET AL. 23...AUG 85 NRL -5627 FNCLASSIFIED /O 12/ NL""lIll"""l 1 0_ 12- 25 1111MI1I" 1111I NRL Memorandum Report 5627 Differential Entropy and the Statistics of...ACCESSiON NO 61153N 02-42 DN180-023 11 TITLE (Include Security Classification) Differential Entropy and the Statistics of Instantaneous Failure Ŗ PERSONAL

  14. Precoding under Instantaneous Per-Antenna Peak Power Constraint

    OpenAIRE

    Jedda, Hela; Mezghani, Amine; Swindlehurst, A. Lee; Nossek, Josef A.

    2016-01-01

    We consider a multi-user (MU) multiple-input-single-output (MISO) downlink system with M single-antenna users and N transmit antennas with a nonlinear power amplifier (PA) at each antenna. Instead of emitting constant envelope (CE) signals from the antennas to have highly power efficient PAs, we relax the CE constraint and allow the transmit signals to have instantaneous power less than or equal to the available power at each PA. The PA power efficiency decreases but simulation results show t...

  15. Heat up and potential failure of BWR upper internals during a severe accident

    Energy Technology Data Exchange (ETDEWEB)

    Robb, Kevin R [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    In boiling water reactors, the steam dome, steam separators, and dryers above the core are comprised of approximately 100 tons of stainless steel. During a severe accident in which the coolant boils away and exothermic oxidation of zirconium occurs, gases (steam and hydrogen) are superheated in the core region and pass through the upper internals. Historically, the upper internals have been modeled using severe accident codes with relatively simple approximations. The upper internals are typically modeled in MELCOR as two lumped volumes with simplified heat transfer characteristics, with no structural integrity considerations, and with limited ability to oxidize, melt, and relocate. The potential for and the subsequent impact of the upper internals to heat up, oxidize, fail, and relocate during a severe accident was investigated. A higher fidelity representation of the shroud dome, steam separators, and steam driers was developed in MELCOR v1.8.6 by extending the core region upwards. This modeling effort entailed adding 45 additional core cells and control volumes, 98 flow paths, and numerous control functions. The model accounts for the mechanical loading and structural integrity, oxidation, melting, flow area blockage, and relocation of the various components. The results indicate that the upper internals can reach high temperatures during a severe accident; they are predicted to reach a high enough temperature such that they lose their structural integrity and relocate. The additional 100 tons of stainless steel debris influences the subsequent in-vessel and ex-vessel accident progression.

  16. Chernobyl accident and its consequences

    Energy Technology Data Exchange (ETDEWEB)

    Gittus, J.H.

    1987-06-01

    The paper concerns the Chernobyl reactor accident, with emphasis on the design of the RBMK reactor and nuclear safety. A description is given of the Chernobyl nuclear power plant, including details of the RMBK reactor and safety systems. Comments on the design of the RBMK by UK experts prior to the accident are summarized, along with post-accident design changes to improve RBMK safety. Events of the Chernobyl accident are described, as well as design deficiencies highlighted by the accident. Differences between the USSR and UK approaches to nuclear safety are commented on. Finally source terms, release periods and environmental consequences are briefly discussed.

  17. Instantaneous velocity profile measurements in a turbulent boundary layer

    Science.gov (United States)

    Robinson, S. K.

    1986-01-01

    Instantaneous wall shear stress and streamwise velocities have been measured simultaneously in a flat-plate, turbulent boundary layer at moderate Reynolds number in an effort to provide experimental support for large eddy simulations. Data were obtained using a buried-wire, wall shear gage and a hot-wire rake positioned in the log region of the flow. Fluctuations of the instantaneous U(+) versus Y(+) profiles about a mean law of the wall are shown to be significant and complex. Peak cross-correlation values between wall shear stress and the velocities are high, and reflect the passage of a large structure inclined at a small angle to the wall. Estimates of this angle are consistent with those made by other investigators. Conditional sampling techniques were used to detect the passage of various sizes and types of flow disturbances (events), and to estimate their mean frequency of occurrence. Events characterized by large aand sudden streamwise accelerations were found to be highly coherent throughout the log region and were strongly correlated with large fluctuations in wall shear stress. Phase randomness between the near-wall quantities and the outer velocities was small. The results suggest that the flow events detected by conditional sampling applied to velocities in the log region may be related to the bursting process.

  18. Instantaneous Bethe-Salpeter Equation and Its Exact Solution

    Institute of Scientific and Technical Information of China (English)

    CHANG Chao-Hsi; CHEN Jiao-Kai; LI Xue-Qian; WANG Guo-Li

    2005-01-01

    We present an approach to solve Bethe-Salpeter (BS) equations exactly without any approximation if the kernel of the BS equations exactly is instantaneous, and take positronium as an example to illustrate the general features of the exact solutions. The key step for the approach is from the BS equations to derive a set of coupled and welldetermined integration equations in linear eigenvalue for the components of the BS wave functions equivalently, which may be solvable numerically under a controlled accuracy, even though there is no analytic solution. For positronium,the exact solutions precisely present corrections to those of the corresponding Schrodinger equation in order v1 (v is the relative velocity) for eigenfunctions, in order v2 for eigenvalues, and the mixing between S and D components in JPC = 1- states etc., quantitatively. Moreover, we also point out that there is a questionable step in some existent derivations for the instantaneous BS equations if one is pursuing the exact solutions. Finally, we emphasize that one should take the O(v) corrections emerging in the exact solutions into account accordingly if one is interested in the relativistic corrections for relevant problems to the bound states.

  19. Instantaneous power flow determination for single-phase UPFC

    Energy Technology Data Exchange (ETDEWEB)

    Dobrucky, B.; Drozdy, S.; Pokorny, M.; Pavlanin, R. [Zilina Univ., Zilina (Slovakia)

    2007-07-01

    The parallel shunt active filter in a unified power flow conditioner (UPFC) can filter and compensate the reactive power of basic and higher current harmonics. This paper reported on a study in which a new theory of orthogonal transform was used to control a single-phase UPFC system and transform it into a two-axes system. In addition to estimating the load current phase shifts, the study also determined the instantaneous active and reactive powers. The new theory is based on the premise that ordinary single-phase quantity can be complemented by a virtual fictitious phase so that both of them will create an orthogonal system, as is usual in three-phase systems. The theory uses efficient methods of analysis, such as time-sub-optimal determination of fundamental harmonics; average- and/or root-mean-square values; or instantaneous reactive power methods. The load current phase shift can be used to compensate for voltage drops. This paper outlined a practical application of the method in a case of active and reactive power determination for single-phase UPFC. It also presented some examples of the successful simulation experiments results focused on regulation output voltage of UPFC. 9 refs., 13 figs., 1 appendix.

  20. A parametric estimation approach to instantaneous spectral imaging.

    Science.gov (United States)

    Oktem, Figen S; Kamalabadi, Farzad; Davila, Joseph M

    2014-12-01

    Spectral imaging, the simultaneous imaging and spectroscopy of a radiating scene, is a fundamental diagnostic technique in the physical sciences with widespread application. Due to the intrinsic limitation of two-dimensional (2D) detectors in capturing inherently three-dimensional (3D) data, spectral imaging techniques conventionally rely on a spatial or spectral scanning process, which renders them unsuitable for dynamic scenes. In this paper, we present a nonscanning (instantaneous) spectral imaging technique that estimates the physical parameters of interest by combining measurements with a parametric model and solving the resultant inverse problem computationally. The associated inverse problem, which can be viewed as a multiframe semiblind deblurring problem (with shift-variant blur), is formulated as a maximum a posteriori (MAP) estimation problem since in many such experiments prior statistical knowledge of the physical parameters can be well estimated. Subsequently, an efficient dynamic programming algorithm is developed to find the global optimum of the nonconvex MAP problem. Finally, the algorithm and the effectiveness of the spectral imaging technique are illustrated for an application in solar spectral imaging. Numerical simulation results indicate that the physical parameters can be estimated with the same order of accuracy as state-of-the-art slit spectroscopy but with the added benefit of an instantaneous, 2D field-of-view. This technique will be particularly useful for studying the spectra of dynamic scenes encountered in space remote sensing.

  1. Instantaneous Frequency and Damping from Transient Ring-Down Data

    Energy Technology Data Exchange (ETDEWEB)

    Kuether, Robert J.; Brake, Matthew Robert

    2015-10-01

    Broadband impact excitation in structural dynamics is a common technique used to detect and characterize nonlinearities in mechanical systems since it excites many frequencies of a structure at once and can be applied with a variety of boundary conditions. Non-stationary time signals from transient ring-down measurements require time-frequency analysis tools to observe variations in frequency and energy dissipation as the response evolves. This work uses the short-time Fourier transform to estimate the instantaneous frequency and damping ratio from either measured or simulated transient ring-down data. By combining the discrete Fourier transform with an expanding or contracting window function that moves along the time axis, the resulting spectrum is used to estimate the instantaneous frequencies, damping and complex Fourier coefficients. This method is demonstrated on a multi-degree-of-freedom beam with a cubic spring attachment, and investigates the amplitudefrequency dependence in connection to the undamped nonlinear normal modes. A second example shows the results from experiment ring-down response on a beam with a lap joint, and reveals how the system behaves as energy dissipates.

  2. Occupational accidents aboard merchant ships

    DEFF Research Database (Denmark)

    Hansen, H.L.; Nielsen, D.; Frydenberg, Morten

    2002-01-01

    Objectives: To investigate the frequency, circumstances, and causes of occupational accidents aboard merchant ships in international trade, and to identify risk factors for the occurrence of occupational accidents as well as dangerous working situations where possible preventive measures may...... be initiated. Methods: The study is a historical follow up on occupational accidents among crew aboard Danish merchant ships in the period 1993–7. Data were extracted from the Danish Maritime Authority and insurance data. Exact data on time at risk were available. Results: A total of 1993 accidents were...... rate of accidents than Danish citizens. Age was a major risk factor for accidents causing permanent disability. Change of ship and the first period aboard a particular ship were identified as risk factors. Walking from one place to another aboard the ship caused serious accidents. The most serious...

  3. Instantaneous Power Compensation in Three-Phase Systems by Using p-q-r Theory

    DEFF Research Database (Denmark)

    Kim, Hyosung; Blaabjerg, Frede; Bak-Jensen, Birgitte;

    2002-01-01

    Three linearly independent instantaneous powers have been defined in the time domain in three-phase four-wire systems with the use of p-q-r theory. Any three-phase circuit can be transformed into three single-phase circuits by the p-q-r transformation Thus the instantaneous powers in any three-phase...... systems can be analysed as the same way of instantaneous power in single-phase systems.This paper analyses the instantaneous powers spectrally in the frequency domain for single-phase systems and three-phase systems. Each instantaneous power in three-phase systems has its own spectral pattern...... that is characterized by the spectral distribution of the system voltages and currents. The instantaneous power in single-phase systems has its own spectral pattern different from that of three-phase systems.From the spectral analysis of the instantaneous powers, powers are newly defined in the frequency domain...

  4. [Drowning accidents in childhood].

    Science.gov (United States)

    Krandick, G; Mantel, K

    1990-09-30

    This is a report on five boys aged between 1 and 5 years who, after prolonged submersion in cold water, were treated at our department. On being taken out of the water, all the patients were clinically dead. After 1- to 3-hour successful cardiopulmonary resuscitation, with a rectal temperature of about 27 degrees C, they were rewarmed at a rate of 1 degree/hour. Two patients died within a few hours after the accident. One patient survived with an apallic syndrome, 2 children survived with no sequelae. In the event of a water-related accident associated with hypothermia, we consider suitable resuscitation to have preference over rewarming measures. The most important treatment guidelines and prognostic factors are discussed.

  5. The effect of blockage on power production for laterally aligned wind turbines

    DEFF Research Database (Denmark)

    Meyer Forsting, Alexander Raul; Troldborg, Niels

    2015-01-01

    This paper studies the change in the individual power coefficients for a laterally aligned row of wind turbines over a single, free turbine in the context of varying inflow directions via numerical simulations. All turbines were rotating in-line with the main flow direction. The problem definition...... to be detrimental in avoiding any domain-inflicted blockage. Increasing the misalignment of the main flow direction with the row of turbines led to significant variations in the power production across turbines. At the largest inflow angle of 45 it varied from -1.1 % to 2 %. As a whole, the power production...

  6. RENEB accident simulation exercise

    OpenAIRE

    Brzozowska, Beata; Ainsbury, Elizabeth; Baert, Annelot; Beaton-Green, Lindsay; Barrios, Leonardo; Barquinero, Joan Francesc; Bassinet, Celine; Beinke, Christina; Benedek, Anett; Beukes, Philip; Bortolin, Emanuela; Buraczewska, Iwona; Burbidge, Christopher; De Amicis, Andrea; De Angelis, Cinzia

    2017-01-01

    Purpose: The RENEB accident exercise was carried out in order to train the RENEB participants in coordinating and managing potentially large data sets that would be generated in case of a major radiological event. Materials and methods: Each participant was offered the possibility to activate the network by sending an alerting email about a simulated radiation emergency. The same participant had to collect, compile and report capacity, triage categorization and exposure scenario results ob...

  7. PREVENTION OF OCCUPATIONAL ACCIDENTS

    Directory of Open Access Journals (Sweden)

    Jovica Jovanovic

    2004-01-01

    Full Text Available Medical services, physicians and nurses play an essential role in the plant safety program through primary treatment of injured workers and by helping to identify workplace hazards. The physician and nurse should participate in the worksite investigations to identify specific hazard or stresses potentially causing the occupational accidents and injuries and in planning the subsequent hazard control program. Physicians and nurses must work closely and cooperatively with supervisors to ensure the prompt reporting and treatment of all work related health and safety problems. Occupational accidents, work related injuries and fatalities result from multiple causes, affect different segments of the working population, and occur in a myriad of occupations and industrial settings. Multiple factors and risks contribute to traumatic injuries, such as hazardous exposures, workplace and process design, work organization and environment, economics, and other social factors. With such a diversity of theories, it will not be difficult to understand that there does not exist one single theory that is considered right or correct and is universally accepted. These theories are nonetheless necessary, but not sufficient, for developing a frame of reference for understanding accident occurrences. Prevention strategies are also varied, and multiple strategies may be applicable to many settings, including engineering controls, protective equipment and technologies, management commitment to and investment in safety, regulatory controls, and education and training. Research needs are thus broad, and the development and application of interventions involve many disciplines and organizations.

  8. Exploring relationships of catheter-associated urinary tract infection and blockage in people with long-term indwelling urinary catheters.

    Science.gov (United States)

    Wilde, Mary H; McMahon, James M; Crean, Hugh F; Brasch, Judith

    2017-09-01

    To describe and explore relationships among catheter problems in long-term indwelling urinary catheter users, including excess healthcare use for treating catheter problems. Long-term urinary catheter users experience repeated problems with catheter-related urinary tract infection and blockage of the device, yet little has been reported of the patterns and relationships among relevant catheter variables. Secondary data analysis was conducted from a sample in a randomised clinical trial, using data from the entire sample of 202 persons over 12 months' participation. Descriptive statistics were used to characterise the sample over time. Zero-inflated negative binomial models were employed for logistic regressions to evaluate predictor variables of the presence/absence and frequencies of catheter-related urinary tract infection and blockage. Catheter-related urinary tract infection was marginally associated with catheter blockage. Problems reported at least once per person in the 12 months were as follows: catheter-related urinary tract infection 57%, blockage 34%, accidental dislodgment 28%, sediment 87%, leakage (bypassing) 67%, bladder spasms 59%, kinks/twists 42% and catheter pain 49%. Regression analysis demonstrated that bladder spasms were significantly related to catheter-related urinary tract infection and sediment amount, and catheter leakages were marginally significantly and positively related to catheter-related urinary tract infection. Frequencies of higher levels of sediment and catheter leakage were significantly associated with higher levels of blockage, and being female was associated with fewer blockages. Persons who need help with eating (more disabled) were also more likely to have blockages. Catheter-related urinary tract infection and blockage appear to be related and both are associated with additional healthcare expenditures. More research is needed to better understand how to prevent adverse catheter outcomes and patterns of problems in

  9. [Detonation temperature measurement of epoxypropane using instantaneous spectrum method].

    Science.gov (United States)

    Li, Ying; Li, Ping; Xiao, Hai-Bo; Hu, Dong; Yuan, Chang-Ying

    2008-03-01

    After solving the problems of synchronization of the measuring system and the avoidance of false trigger signal, the instantaneous emission spectrum of epoxypropane with an exposure time of 2 micros and a resolution of 0.2 nm was acquired from a side window of a shock tube at the very moment when the epoxypropane transformed from deflagration to detonation. The measuring system consists of an advanced intensified charge-coupled-device spectroscopic detector, a digital delay generator DG535, an explosion shock tube and optical fibers. The DDT process was monitored by pressure transducers. After correcting the intensity of the spectrum obtained, the background curve of the heat radiation intensity of the detonation was given immediately. The detonation temperature of 2 416 K for epoxypropane was derived from fitting the curve with Planck blackbody formula by least squares principle. The detonation temperature of epoxypropane can provide an experimental datum for analyzing the microscopic mechanism of DDT process.

  10. Video measurements of instantaneous forces of flapping wing vehicles

    Science.gov (United States)

    Jennings, Alan; Mayhew, Michael; Black, Jonathan

    2015-12-01

    Flapping wings for small aerial vehicles have revolutionary potential for maneuverability and endurance. Ornithopters fail to achieve the performance of their biological equivalents, despite extensive research on how animals fly. Flapping wings produce peak forces due to the stroke reversal of the wing. This research demonstrates in-flight measurements of an ornithopter through the use of image processing, specifically measuring instantaneous forces. Results show that the oscillation about the flight path is significant, being about 20% of the mean velocity and up to 10 g's. Results match forces with deformations of the wing to contrast the timing and wing shape of the upstroke and the downstroke. Holding the vehicle fixed (e.g. wind tunnel testing or simulations) structural resonance is affected along with peak forces, also affecting lift. Non-contact, in-flight measurements are proposed as the best method for matching the flight conditions of flapping wing vehicles.

  11. Instantaneous Action at a Distance in a Holistic Universe

    CERN Document Server

    Sidharth, B G

    1998-01-01

    The early work of Lorentz, Abraham and others, evolved through the work of Fokker, Dirac and others to ultimately culminate in the Feynman- Wheeler direct action at a distance theory. However this theory has encountered certain conceptual difficulties like non-locality in time, self force of the electron, pre acceleration and the perfect absorption condition of Feynman and Wheeler, that is the instantaneous action of the remaining charges in the universe on the charge in question. More recently, Hoyle and Narlikar have resurrected this theory, but within the context of a Steady State or Quasi Steady State cosmology. They argue that the theory infact has a better standing than the generally accepted quantum theoretic description. In this article we consider a quantum theoretic description and a cosmology which parallels the Hoyle-Narlikar approach. This leads to a synthesis and justification of the Dirac and Feynman-Wheeler approaches, clarifying the conceptual problems in the process. We deduce a scenario wit...

  12. Fractional flow reserve and instantaneous wave free ratio in 2015.

    Science.gov (United States)

    Kondareddy, S R; Singh, M; Stapleton, D; Rudzinski, W; Kaluski, E

    2015-06-01

    In the recent years it has become apparent that angiography-based assessment of coronary artery stenosis suffers from considerable inaccuracy and pitfalls. Besides interobserver variability in assessing stenosis severity, the correlation between angiographic severity and ischemia is suboptimal. Percutaneous coronary intervention (PCI) guided by the physiologic lesion assessment employing fractional flow reserve (FFR) is rendered superior to angiographic lesion assessment and proven to improve cardiovascular outcomes and reduce cost. In this manuscript we discuss the accepted and emerging clinical indications for FFR use. The correlation between FFR and symptoms, stress imaging and intravascular ultrasound are reviewed along with the inherent limitations and pitfalls of these diagnostic technologies. The data regarding the correlation between Instantaneous (vasodilator free) wave-free ratio (iFR) and conventional FFR is summarized.

  13. [Chernobyl nuclear power plant accident and Tokaimura criticality accident].

    Science.gov (United States)

    Takada, Jun

    2012-03-01

    It is clear from inspection of historical incidents that the scale of disasters in a nuclear power plant accident is quite low level overwhelmingly compared with a nuclear explosion in nuclear war. Two cities of Hiroshima and Nagasaki were destroyed by nuclear blast with about 20 kt TNT equivalent and then approximately 100,000 people have died respectively. On the other hand, the number of acute death is 30 in the Chernobyl nuclear reactor accident. In this chapter, we review health hazards and doses in two historical nuclear incidents of Chernobyl and Tokaimura criticality accident and then understand the feature of the radiation accident in peaceful utilization of nuclear power.

  14. Local blockage of EMMPRIN impedes pressure ulcers healing in a rat model.

    Science.gov (United States)

    Zhao, Xi-Lan; Luo, Xiao; Wang, Ze-Xin; Yang, Guo-Li; Liu, Ji-Zhong; Liu, Ya-Qiong; Li, Ming; Chen, Min; Xia, Yong-Mei; Liu, Jun-Jie; Qiu, Shu-Ping; Gong, Xiao-Qing

    2015-01-01

    Excessive extracellular matrix degradation caused by the hyperfunction of matrix metalloproteinases (MMPs) has been implicated in the failure of pressure ulcers healing. EMMPRIN, as a widely expressed protein, has emerged as an important regulator of MMP activity. We hypothesize that EMMPRIN affects the process of pressure ulcer healing by modulating MMP activity. In the rat pressure ulcer model, the expression of EMMPRIN in ulcers detected by Western blot was elevated compared with that observed in normal tissue. To investigate the role of EMMPRIN in regulating ulcer healing, specific antibodies against EMMPRIN were used via direct administration on the pressure ulcer. Local blockage of EMMPRIN resulted in a poor ulcer healing process compared with control ulcers, which was the opposite of our expectation. Furthermore, inhibiting EMMPRIN minimally impacted MMP activity. However, the collagen content in the pressure ulcer was reduced in the EMMPRIN treated group. Angiogenesis and the expression of angiogenic factors in pressure ulcers were also reduced by EMMPRIN local blockage. The results in the present study indicate a novel effect of EMMPRIN in the regulation of pressure ulcer healing by controlling the collagen contents and angiogenesis rather than MMPs activity.

  15. Percolation blockage: A process that enables melt pond formation on first year Arctic sea ice

    Science.gov (United States)

    Polashenski, Chris; Golden, Kenneth M.; Perovich, Donald K.; Skyllingstad, Eric; Arnsten, Alexandra; Stwertka, Carolyn; Wright, Nicholas

    2017-01-01

    Melt pond formation atop Arctic sea ice is a primary control of shortwave energy balance in the Arctic Ocean. During late spring and summer, the ponds determine sea ice albedo and how much solar radiation is transmitted into the upper ocean through the sea ice. The initial formation of ponds requires that melt water be retained above sea level on the ice surface. Both theory and observations, however, show that first year sea ice is so highly porous prior to the formation of melt ponds that multiday retention of water above hydraulic equilibrium should not be possible. Here we present results of percolation experiments that identify and directly demonstrate a mechanism allowing melt pond formation. The infiltration of fresh water into the pore structure of sea ice is responsible for blocking percolation pathways with ice, sealing the ice against water percolation, and allowing water to pool above sea level. We demonstrate that this mechanism is dependent on fresh water availability, known to be predominantly from snowmelt, and ice temperature at melt onset. We argue that the blockage process has the potential to exert significant control over interannual variability in ice albedo. Finally, we suggest that incorporating the mechanism into models would enhance their physical realism. Full treatment would be complex. We provide a simple temperature threshold-based scheme that may be used to incorporate percolation blockage behavior into existing model frameworks.

  16. Blockage of transient receptor potential vanilloid 4 inhibits brain edema in middle cerebral artery occlusion mice.

    Science.gov (United States)

    Jie, Pinghui; Tian, Yujing; Hong, Zhiwen; Li, Lin; Zhou, Libin; Chen, Lei; Chen, Ling

    2015-01-01

    Brain edema is an important pathological process during stroke. Activation of transient receptor potential vanilloid 4 (TRPV4) causes an up-regulation of matrix metalloproteinases (MMPs) in lung tissue. MMP can digest the endothelial basal lamina to destroy blood brain barrier, leading to vasogenic brain edema. Herein, we tested whether TRPV4-blockage could inhibit brain edema through inhibiting MMPs in middle cerebral artery occlusion (MCAO) mice. We found that the brain water content and Evans blue extravasation at 48 h post-MCAO were reduced by a TRPV4 antagonist HC-067047. The increased MMP-2/9 protein expression in hippocampi of MCAO mice was attenuated by HC-067046, but only the increased MMP-9 activity was blocked by HC-067047. The loss of zonula occludens-1 (ZO-1) and occludin protein in MCAO mice was also attenuated by HC-067047. Moreover, MMP-2/9 protein expression increased in mice treated with a TRPV4 agonist GSK1016790A, but only MMP-9 activity was increased by GSK1016790A. Finally, ZO-1 and occludin protein expression was decreased by GSK1016790A, which was reversed by an MMP-9 inhibitor. We conclude that blockage of TRPV4 may inhibit brain edema in cerebral ischemia through inhibiting MMP-9 activation and the loss of tight junction protein.

  17. Blockage Testing in the NASA Glenn 225 Square Centimeter Supersonic Wind Tunnel

    Science.gov (United States)

    Sevier, Abigail; Davis, David; Schoenenberger, Mark

    2017-01-01

    A feasibility study is in progress at NASA Glenn Research Center to implement a magnetic suspension and balance system in the 225 sq cm Supersonic Wind Tunnel for the purpose of testing the dynamic stability of blunt bodies. An important area of investigation in this study was determining the optimum size of the model and the iron spherical core inside of it. In order to minimize the required magnetic field and thus the size of the magnetic suspension system, it was determined that the test model should be as large as possible. Blockage tests were conducted to determine the largest possible model that would allow for tunnel start at Mach 2, 2.5, and 3. Three different forebody model geometries were tested at different Mach numbers, axial locations in the tunnel, and in both a square and axisymmetric test section. Experimental results showed that different model geometries produced more varied results at higher Mach Numbers. It was also shown that testing closer to the nozzle allowed larger models to start compared with testing near the end of the test section. Finally, allowable model blockage was larger in the axisymmetric test section compared with the square test section at the same Mach number. This testing answered key questions posed by the feasibility study and will be used in the future to dictate model size and performance required from the magnetic suspension system.

  18. Blockage of IGF-1R signaling sensitizes urinary bladder cancer cells to mitomycin-mediated cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A major problem which is poorly understood in the management of bladder cancer is low sensitivity to chemotherapy and high recurrence after transurethral resection.Insulin-like growth factor 1 receptor(IGF-1R)signaling plays a very important role in progression,invasion and metastasis of bladder cancer cells.In this study,we investigated whether IGF-1R was involved in the growth stimulating activity and drug resistance of bladder cancer cells.The results showed: The mRNAs of IGF-1,IGF-2 and IGF-1R were strongly expressed in serum-free cultured T24 cell line,whereas normal urothelial cells did not express these factors/receptors or only in trace levels; T24 cell responded far better to growth stimulation by IGF-1 than did normal urothelial cells; blockage of IGF1R by antisense oligodeoxynucleotide(ODN)significantly inhibited the growth of T24 cell and enhanced sensitivity and apoptosis of T24 cells to mitomycin(MMC).These results suggested that blockage of IGF-IR signaling might potentially contribute to the treatment of bladder cancer cells which are insensitive to chemotherapy.

  19. Estimates of pressure gradients in PEMFC gas channels due to blockage by static liquid drops

    Energy Technology Data Exchange (ETDEWEB)

    Venkatraman, M.; Shimpalee, S.; Van Zee, J.W. [Department of Chemical Engineering, University of South Carolina, 301 Main St., Columbia, SC 29208 (United States); Moon, Sung In; Extrand, C.W. [Entegris, Inc., 3500 Lyman Boulevard, Chaska, MN 55318 (United States)

    2009-07-15

    Numerical analyses are presented to explain the effect of drop size and contact angle on local pressures inside small channels. These pressures and channel characteristics are of interest when water condenses in the gas channels of Proton Exchange Membrane Fuel Cells and hence the study uses Reynolds numbers consistent with as typical utilization of reacting gases in 200 cm{sup 2} flow fields (i.e., 200 < Re < 1500 and stoichiometries of 1.2-2.0 at 1.0 A/cm{sup 2}). The analyses were performed using three-dimensional computational fluid dynamic techniques and the results show that pressure drops are minimal until the blockage was greater than 50%. As blockage increased further, due to larger drops or increased hydrophobicity, pressure drop increased. The results of a stagnant drop are supported by visualization experiments, which show minimal distortion of the drop for these low flow rates, small ratios, and hydrophobic contact angles. Proper scaling parameters and design criteria for microchannels validation experiments are presented. (author)

  20. Connectivity Analysis of Millimeter-Wave Device-to-Device Networks with Blockage

    Directory of Open Access Journals (Sweden)

    Haejoon Jung

    2016-01-01

    Full Text Available We consider device-to-device (D2D communications in millimeter-wave (mm Wave for the future fifth generation (5G cellular networks. While the mm Wave systems can support multiple D2D pairs simultaneously through beamforming with highly directional antenna arrays, the mm Wave channel is significantly more susceptible to blockage compared to microwave; mm Wave channel studies indicate that if line-of-sight (LoS paths are blocked, reliable mm Wave communications may not be achieved for high data-rate applications. Therefore, assuming that an outage occurs in the absence of the LoS path between two wireless devices by obstructions, we focus on connectivity of the mm Wave D2D networks. We consider two types of D2D communications: direct and indirect schemes. The connectivity performances of the two schemes are investigated in terms of (i the probability to achieve a fully connected network PFC and (ii the average number of reliably connected devices γ. Through analysis and simulation, we show that, as the network size increases, PFC and γ decrease. Also, PFC and γ decrease, when the blockage parameter increases. Moreover, simulation results indicate that the hybrid direct and indirect scheme can improve both PFC and γ up to about 35% compared to the nonhybrid scheme.

  1. Estimation of the Frequency of Instantaneous Voltage Drops Dependent on Arrangement of Line Surge Arresters

    Science.gov (United States)

    Kawamura, Hironao; Kozuka, Masahiro; Itamoto, Naoki; Shinjo, Kazuo; Ishii, Masaru

    Lightning faults on transmission lines often cause instantaneous voltage drops in power systems. Influences of instantaneous voltage drops become increasingly serious in high technology industries etc. As countermeasures of instantaneous voltage drops, uninterruptible power supplies (UPS) are employed. On the other hand, line surge arresters are installed on transmission lines increasingly as one of the effective countermeasures of double-circuit faults caused by lightning strokes. Additionally, the arresters are effective as one of the reduction methods for the frequency of instantaneous voltage drops. In this paper, the frequency of instantaneous voltage drops reduced by installation of line surge arresters on transmission lines is estimated by employing EMTP analysis. Also, the accuracy of the method in estimating the frequency of instantaneous voltage drops in power systems is evaluated through comparison with experience.

  2. Radiation accident grips Goiania

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, L.

    1987-11-20

    On 13 September two young scavengers in Goiania, Brazil, removed a stainless steel cylinder from a cancer therapy machine in an abandoned clinic, touching off a radiation accident second only to Chernobyl in its severity. On 18 September they sold the cylinder, the size of a 1-gallon paint can, to a scrap dealer for $25. At the junk yard an employee dismantled the cylinder and pried open the platinum capsule inside to reveal a glowing blue salt-like substance - 1400 curies of cesium-137. Fascinated by the luminescent powder, several people took it home with them. Some children reportedly rubbed in on their bodies like carnival glitter - an eerie image of how wrong things can go when vigilance over radioactive materials lapses. In all, 244 people in Goiania, a city of 1 million in central Brazil, were contaminated. The eventual toll, in terms of cancer or genetic defects, cannot yet be estimated. Parts of the city are cordoned off as radiation teams continue washing down buildings and scooping up radioactive soil. The government is also grappling with the political fallout from the accident.

  3. Research on Instantaneous Thrust Measurement for Attitude-control Solid Rocket Motor

    Institute of Scientific and Technical Information of China (English)

    OUYANG Hua-bing; WANG Jian-ping; LIN Feng; XU Wen-gan

    2008-01-01

    In order to measure the instantaneous thrust of a certain attitude-control solid rocket motor, based on the analysis of the measurement principles, the difference between the instantaneous thrust and steady thrust measurements is pointed out. According to the measurement characteristics, a dynamic digital filter compensation method is presented. Combined the identification-modeling, dynamic compensation and simulation, the system's dynamic mathematic model is established. And then, a compensation digital filter is also designed. Thus, the dynamic response of the system is improved and the instantaneous thrust measurement can be implemented. The measurement results for the rocket motor show that the digital filter compensation is effective in the instantaneous thrust measurement.

  4. Emergency cricothyrotomy for trismus caused by instantaneous rigor in cardiac arrest patients.

    Science.gov (United States)

    Lee, Jae Hee; Jung, Koo Young

    2012-07-01

    Instantaneous rigor as muscle stiffening occurring in the moment of death (or cardiac arrest) can be confused with rigor mortis. If trismus is caused by instantaneous rigor, orotracheal intubation is impossible and a surgical airway should be secured. Here, we report 2 patients who had emergency cricothyrotomy for trismus caused by instantaneous rigor. This case report aims to help physicians understand instantaneous rigor and to emphasize the importance of securing a surgical airway quickly on the occurrence of trismus. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. A free-blockage controlled release system based on the hydrophobic/hydrophilic conversion of mesoporous silica nanopores.

    Science.gov (United States)

    Wang, Wenqian; Chen, Linfeng; Xu, Li-Ping; Du, Hongwu; Wen, Yongqiang; Song, Yanlin; Zhang, Xueji

    2015-02-02

    A pH-responsive free-blockage release system was achieved through controlling the hydrophobic/hydrophilic conversion of mesoporous silica nanopores. This system further presented pulsatile release with changing pH values between 4.0 and 7.0 for several cycles. This free-blockage release system could also release antitumor agents to induce cell death after infecting tumor cells and could have the ability of continuous infection to tumor cells with high drug-delivery efficiency and few side effects.

  6. Fatal motorcycle accidents and alcohol

    DEFF Research Database (Denmark)

    Larsen, C F; Hardt-Madsen, M

    1987-01-01

    A series of fatal motorcycle accidents from a 7-year period (1977-1983) has been analyzed. Of the fatalities 30 were operators of the motorcycle, 11 pillion passengers and 8 counterparts. Of 41 operators 37% were sober at the time of accident, 66% had measurable blood alcohol concentration (BAC...

  7. Learning from incidents and accidents

    NARCIS (Netherlands)

    Drupsteen, L.; Kampen, J. van

    2014-01-01

    There are many different definitions for what constitutes an incident or an accident, however the focus is always on unintended and often unforeseen events that cause unintended consequences. This article is focused on the process of learning from incidents and accidents. The focus is on making sure

  8. [Practical management of CPB accident].

    Science.gov (United States)

    Depoix, J-P; Fenet, L; Provenchere, S

    2012-05-01

    Accident of CPB is a reality. It is important to be prepared for discussion with the family, with the hospital administration, eventually with the justice. But we have also to support perfusionnist and anesthetic team in charge of the patient during accident.

  9. Learning from incidents and accidents

    NARCIS (Netherlands)

    Drupsteen, L.; Kampen, J. van

    2014-01-01

    There are many different definitions for what constitutes an incident or an accident, however the focus is always on unintended and often unforeseen events that cause unintended consequences. This article is focused on the process of learning from incidents and accidents. The focus is on making sure

  10. Effect of extradural blockage upon glucose and urea kinetics in surgical patients

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, J.H.; Galler, L.; Holdaway, I.M.; Holdaway, C.M.

    1987-09-01

    We have determined the metabolic effects induced by the use of extradural blockage with 0.5 per cent bupivacaine hydrochloride in a group of surgical patients. Turnover rates of glucose and urea were determined isotopically using radioisotopes and studies were performed both in the basal state and during total parenteral nutrition. In the basal state, extradural blockade resulted in a decrease in the turnover rates of both glucose and urea. In addition, when extradural blockade was instituted while the patients were receiving total parenteral nutrition, there was also a significant fall in glucose turnover. We conclude that the use of extradural blockade is effective as a means of conserving bodily resources in surgical patients both in the basal state and during total parenteral nutrition.

  11. Blockage of Notch Signaling Inhibits the Migration and Proliferation of Retinal Pigment Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Weiwei Liu

    2013-01-01

    Full Text Available The Notch signaling is an evolutionarily conserved cell-cell communication pathway that plays critical roles in the proliferation, survival, apoptosis, and fate determination of mammalian cells. Retinal pigment epithelial (RPE cells are responsible for supporting the function of the neural retina and maintaining vision. This study investigated the function of Notch signaling in RPE cells. We found that the members of the Notch signaling pathway components were differentially expressed in RPE cells. Furthermore, blockage of Notch signaling inhibited the migration and proliferation of RPE cells and reduced the expression levels of certain Notch signaling target genes, including HES1, MYC, HEY2, and SOX9. Our data reveal a critical role of Notch signaling in RPE cells, suggesting that targeting Notch signaling may provide a novel approach for the treatment of ophthalmic diseases related to RPE cells.

  12. The effect of blockage on power production for laterally aligned wind turbines

    Science.gov (United States)

    Meyer Forsting, A. R.; Troldborg, N.

    2015-06-01

    This paper studies the change in the individual power coefficients for a laterally aligned row of wind turbines over a single, free turbine in the context of varying inflow directions via numerical simulations. All turbines were rotating in-line with the main flow direction. The problem definition is similar to that of many wind turbine testing sites and wind farms. Hence any changes in the individual turbine power production could have implications regarding power curve validation procedures.These changes are relatively small and therefore the size of the computational domain was identified to be detrimental in avoiding any domain-inflicted blockage. Increasing the misalignment of the main flow direction with the row of turbines led to significant variations in the power production across turbines. At the largest inflow angle of 45° it varied from -1.1% to 2%. As a whole, the power production increased by about 0.5%, almost independent of the inflow direction.

  13. Development and evaluation of an instantaneous atmospheric corrosion rate monitor

    Science.gov (United States)

    Mansfeld, F.; Jeanjaquet, S. L.; Kendig, M. W.; Roe, D. K.

    1985-06-01

    A research program was carried out in which a new instantaneous atmospheric corrosion rate monitor (ACRM) was developed and evaluated, and equipment was constructed which will allow the use of many sensors in an economical way in outdoor exposures. In the first task, the ACRM was developed and tested in flow chambers in which relative humidity and gaseous and particulate pollutant levels can be controlled. Diurnal cycles and periods of rain were simulated. The effects of aerosols were studied. A computerized system was used for collection, storage, and analysis of the electrochemical data. In the second task, a relatively inexpensive electronics system for control of the ACRM and measurement of atmospheric corrosion rates was designed and built. In the third task, calibration of deterioration rates of various metallic and nonmetallic materials with the response of the ACRMs attached to these materials was carried out under controlled environmental conditions using the system developed in the second task. A Quality Assurance project plan was prepared with inputs from the Rockwell International Environmental Monitoring and Service Center and Quality Assurance System audits were performed.

  14. Constraining the instantaneous aerosol influence on cloud albedo

    Energy Technology Data Exchange (ETDEWEB)

    Gryspeerdt, Edward; Quaas, Johannes; Ferrachat, Sylvaine; Gettelman, Andrew; Ghan, Steven; Lohmann, Ulrike; Morrison, Hugh; Neubauer, David; Partridge, Daniel G.; Stier, Philip; Takemura, Toshihiko; Wang, Hailong; Wang, Minghuai; Zhang, Kai

    2017-04-26

    Much of the uncertainty in estimates of the anthropogenic forcing of climate change comes from uncertainties in the instantaneous effect of aerosols on cloud albedo, known as the Twomey effect or the radiative forcing from aerosol–cloud interactions (RFaci), a component of the total or effective radiative forcing. Because aerosols serving as cloud condensation nuclei can have a strong influence on the cloud droplet number concentration (Nd), previous studies have used the sensitivity of the Nd to aerosol properties as a constraint on the strength of the RFaci. However, recent studies have suggested that relationships between aerosol and cloud properties in the present-day climate may not be suitable for determining the sensitivity of the Nd to anthropogenic aerosol perturbations. Using an ensemble of global aerosol–climate models, this study demonstrates how joint histograms between Nd and aerosol properties can account for many of the issues raised by previous studies. It shows that if the anthropogenic contribution to the aerosol is known, the RFaci can be diagnosed to within 20% of its actual value. The accuracy of different aerosol proxies for diagnosing the RFaci is investigated, confirming that using the aerosol optical depth significantly underestimates the strength of the aerosol–cloud interactions in satellite data.

  15. User-interactive electronic skin for instantaneous pressure visualization

    Science.gov (United States)

    Wang, Chuan; Hwang, David; Yu, Zhibin; Takei, Kuniharu; Park, Junwoo; Chen, Teresa; Ma, Biwu; Javey, Ali

    2013-10-01

    Electronic skin (e-skin) presents a network of mechanically flexible sensors that can conformally wrap irregular surfaces and spatially map and quantify various stimuli. Previous works on e-skin have focused on the optimization of pressure sensors interfaced with an electronic readout, whereas user interfaces based on a human-readable output were not explored. Here, we report the first user-interactive e-skin that not only spatially maps the applied pressure but also provides an instantaneous visual response through a built-in active-matrix organic light-emitting diode display with red, green and blue pixels. In this system, organic light-emitting diodes (OLEDs) are turned on locally where the surface is touched, and the intensity of the emitted light quantifies the magnitude of the applied pressure. This work represents a system-on-plastic demonstration where three distinct electronic components—thin-film transistor, pressure sensor and OLED arrays—are monolithically integrated over large areas on a single plastic substrate. The reported e-skin may find a wide range of applications in interactive input/control devices, smart wallpapers, robotics and medical/health monitoring devices.

  16. Adaptive Window Zero-Crossing-Based Instantaneous Frequency Estimation

    Directory of Open Access Journals (Sweden)

    S. Chandra Sekhar

    2004-09-01

    Full Text Available We address the problem of estimating instantaneous frequency (IF of a real-valued constant amplitude time-varying sinusoid. Estimation of polynomial IF is formulated using the zero-crossings of the signal. We propose an algorithm to estimate nonpolynomial IF by local approximation using a low-order polynomial, over a short segment of the signal. This involves the choice of window length to minimize the mean square error (MSE. The optimal window length found by directly minimizing the MSE is a function of the higher-order derivatives of the IF which are not available a priori. However, an optimum solution is formulated using an adaptive window technique based on the concept of intersection of confidence intervals. The adaptive algorithm enables minimum MSE-IF (MMSE-IF estimation without requiring a priori information about the IF. Simulation results show that the adaptive window zero-crossing-based IF estimation method is superior to fixed window methods and is also better than adaptive spectrogram and adaptive Wigner-Ville distribution (WVD-based IF estimators for different signal-to-noise ratio (SNR.

  17. Constraining the instantaneous aerosol influence on cloud albedo.

    Science.gov (United States)

    Gryspeerdt, Edward; Quaas, Johannes; Ferrachat, Sylvaine; Gettelman, Andrew; Ghan, Steven; Lohmann, Ulrike; Morrison, Hugh; Neubauer, David; Partridge, Daniel G; Stier, Philip; Takemura, Toshihiko; Wang, Hailong; Wang, Minghuai; Zhang, Kai

    2017-05-09

    Much of the uncertainty in estimates of the anthropogenic forcing of climate change comes from uncertainties in the instantaneous effect of aerosols on cloud albedo, known as the Twomey effect or the radiative forcing from aerosol-cloud interactions (RFaci), a component of the total or effective radiative forcing. Because aerosols serving as cloud condensation nuclei can have a strong influence on the cloud droplet number concentration (Nd ), previous studies have used the sensitivity of the Nd to aerosol properties as a constraint on the strength of the RFaci. However, recent studies have suggested that relationships between aerosol and cloud properties in the present-day climate may not be suitable for determining the sensitivity of the Nd to anthropogenic aerosol perturbations. Using an ensemble of global aerosol-climate models, this study demonstrates how joint histograms between Nd and aerosol properties can account for many of the issues raised by previous studies. It shows that if the anthropogenic contribution to the aerosol is known, the RFaci can be diagnosed to within 20% of its actual value. The accuracy of different aerosol proxies for diagnosing the RFaci is investigated, confirming that using the aerosol optical depth significantly underestimates the strength of the aerosol-cloud interactions in satellite data.

  18. Instantaneous Respiratory Estimation from Thoracic Impedance by Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Fu-Tai Wang

    2015-07-01

    Full Text Available Impedance plethysmography provides a way to measure respiratory activity by sensing the change of thoracic impedance caused by inspiration and expiration. This measurement imposes little pressure on the body and uses the human body as the sensor, thereby reducing the need for adjustments as body position changes and making it suitable for long-term or ambulatory monitoring. The empirical mode decomposition (EMD can decompose a signal into several intrinsic mode functions (IMFs that disclose nonstationary components as well as stationary components and, similarly, capture respiratory episodes from thoracic impedance. However, upper-body movements usually produce motion artifacts that are not easily removed by digital filtering. Moreover, large motion artifacts disable the EMD to decompose respiratory components. In this paper, motion artifacts are detected and replaced by the data mirrored from the prior and the posterior before EMD processing. A novel intrinsic respiratory reconstruction index that considers both global and local properties of IMFs is proposed to define respiration-related IMFs for respiration reconstruction and instantaneous respiratory estimation. Based on the experiments performing a series of static and dynamic physical activates, our results showed the proposed method had higher cross correlations between respiratory frequencies estimated from thoracic impedance and those from oronasal airflow based on small window size compared to the Fourier transform-based method.

  19. Traffic Accidents on Slippery Roads

    DEFF Research Database (Denmark)

    Fonnesbech, J. K.; Bolet, Lars

    2014-01-01

    Police registrations from 65 accidents on slippery roads in normally Danish winters have been studied. The study showed: • 1 accident per 100 km when using brine spread with nozzles • 2 accidents per 100 km when using pre wetted salt • 3 accidents per 100 km when using kombi spreaders The results...... of accidents in normally Danish winter seasons are remarkable alike the amount of salt used in praxis in the winter 2011/2012. • 2.7 ton NaCl/km when using brine spread with nozzles • 5 ton NaCl/km when using pre wetted salt. • 5.7 ton NaCl/km when using kombi spreaders The explanation is that spreading...

  20. Corporate Cost of Occupational Accidents

    DEFF Research Database (Denmark)

    Rikhardsson, Pall M.; Impgaard, M.

    2004-01-01

    method could be used in all of the companies without revisions. The evaluation of accident cost showed that 2/3 of the costs of occupational accidents are visible in the Danish corporate accounting systems reviewed while 1/3 is hidden from management view. The highest cost of occupational accidents......The systematic accident cost analysis (SACA) project was carried out during 2001 by The Aarhus School of Business and PricewaterhouseCoopers Denmark with financial support from The Danish National Working Environment Authority. Its focused on developing and testing a method for evaluating...... occupational costs of companies for use by occupational health and safety professionals. The method was tested in nine Danish companies within three different industry sectors and the costs of 27 selected occupational accidents in these companies were calculated. One of the main conclusions is that the SACA...

  1. Industrial accidents triggered by lightning.

    Science.gov (United States)

    Renni, Elisabetta; Krausmann, Elisabeth; Cozzani, Valerio

    2010-12-15

    Natural disasters can cause major accidents in chemical facilities where they can lead to the release of hazardous materials which in turn can result in fires, explosions or toxic dispersion. Lightning strikes are the most frequent cause of major accidents triggered by natural events. In order to contribute towards the development of a quantitative approach for assessing lightning risk at industrial facilities, lightning-triggered accident case histories were retrieved from the major industrial accident databases and analysed to extract information on types of vulnerable equipment, failure dynamics and damage states, as well as on the final consequences of the event. The most vulnerable category of equipment is storage tanks. Lightning damage is incurred by immediate ignition, electrical and electronic systems failure or structural damage with subsequent release. Toxic releases and tank fires tend to be the most common scenarios associated with lightning strikes. Oil, diesel and gasoline are the substances most frequently released during lightning-triggered Natech accidents.

  2. Typologie des Accidents Cyclistes

    OpenAIRE

    Amoros, Emmanuelle; BILLOT-GRASSET, Alice; Hours, Martine

    2015-01-01

    L'usage du vélo est en hausse en ville ; cette pratique est encouragée dans le cadre du développement durable et de la lutte contre la sédentarité. Pour accompagner cela, il faut réduire les risques d'accident, et pour ce faire, mieux les connaître. Nous utilisons le Registre des victimes de la circulation routière du Rhône, basé sur les services hospitaliers (dont les urgences) ; il est quasi-exhaustif : env. 1100 blessés à vélo/an versus 120 dans les données officielles. L'ensemble des cycl...

  3. Airborne laser scan data: a valuable tool with which to infer weather radar partial beam blockage in urban environments

    Science.gov (United States)

    Cremonini, Roberto; Moisseev, Dmitri; Chandrasekar, Venkatachalam

    2016-10-01

    High-spatial-resolution weather radar observations are of primary relevance for hydrological applications in urban areas. However, when weather radars are located within metropolitan areas, partial beam blockages and clutter by buildings can seriously affect the observations. Standard simulations with simple beam propagation models and digital elevation models (DEMs) are usually not able to evaluate buildings' contribution to partial beam blockages. In recent years airborne laser scanners (ALSs) have evolved to the state-of-the-art technique for topographic data acquisition. Providing small footprint diameters (10-30 cm), ALS data allow accurate reconstruction of buildings and forest canopy heights. Analyzing the three weather C-band radars located in the metropolitan area of Helsinki, Finland, the present study investigates the benefits of using ALS data for quantitative estimations of partial beam blockages. The results obtained applying beam standard propagation models are compared with stratiform 24 h rainfall accumulation to evaluate the effects of partial beam blockages due to constructions and trees. To provide a physical interpretation of the results, the detailed analysis of beam occultations is achieved by open spatial data sets and open-source geographic information systems.

  4. Three-Dimensional, Numerical Investigation of Flow and Heat Transfer in Rectangular Channels Subject to Partial Blockage

    KAUST Repository

    Salama, Amgad

    2014-08-25

    Numerical simulation of flow and heat transfer in two adjacent channels is conducted with one of the channels partially blocked. This system simulates typical channels of a material testing reactor. The blockage is assumed due to the buckling of one of the channel plates inward along its width. The blockage ratio considered in this work is defined as the ratio between the cross-sectional area of the blocked and the unblocked channel. In this work, we consider a blockage ratio of approximately 40%. However, the blockage is different along the width of the channel, ranging from 0% at the end of the channel to 90% in the middle. The channel walls are sandwiching volumetric heat sources that vary spatially as chopped cosine functions. Interesting patterns are highlighted and investigated. The reduction in the flow area of one channel results in the flow redistributing among the two channels according to the changes in their hydraulic conductivities. The results of the numerical simulations show that the maximum wall temperature in the blocked channel is well below the boiling temperature at the operating pressure.

  5. Validation of attenuation, beam blockage, and calibration estimation methods using two dual polarization X band weather radars

    Science.gov (United States)

    Diederich, M.; Ryzhkov, A.; Simmer, C.; Mühlbauer, K.

    2011-12-01

    The amplitude a of radar wave reflected by meteorological targets can be misjudged due to several factors. At X band wavelength, attenuation of the radar beam by hydro meteors reduces the signal strength enough to be a significant source of error for quantitative precipitation estimation. Depending on the surrounding orography, the radar beam may be partially blocked when scanning at low elevation angles, and the knowledge of the exact amount of signal loss through beam blockage becomes necessary. The phase shift between the radar signals at horizontal and vertical polarizations is affected by the hydrometeors that the beam travels through, but remains unaffected by variations in signal strength. This has allowed for several ways of compensating for the attenuation of the signal, and for consistency checks between these variables. In this study, we make use of several weather radars and gauge network measuring in the same area to examine the effectiveness of several methods of attenuation and beam blockage corrections. The methods include consistency checks of radar reflectivity and specific differential phase, calculation of beam blockage using a topography map, estimating attenuation using differential propagation phase, and the ZPHI method proposed by Testud et al. in 2000. Results show the high effectiveness of differential phase in estimating attenuation, and potential of the ZPHI method to compensate attenuation, beam blockage, and calibration errors.

  6. Effect of Local Nasal Immunotherapy on Nasal Blockage in Pollen-Induced Allergic Rhinitis of Guinea Pigs

    Directory of Open Access Journals (Sweden)

    Takeshi Nabe

    2008-01-01

    Conclusions: Local nasal immunotherapy may be clinically useful for allergic nasal blockage associated with nasal hyperresponsiveness. The mechanisms responsible for this effectiveness might not be related to IgE production. Additionally, the effectiveness for nasal tissue was dissociated from that seen for the ocular tissue.

  7. Wind-tunnel blockage and actuation systems test of a two-dimensional scramjet inlet unstart model at Mach 6

    Science.gov (United States)

    Holland, Scott D.

    1994-01-01

    The present study examines the wind-tunnel blockage and actuation systems effectiveness in starting and forcibly unstarting a two-dimensional scramjet inlet in the NASA Langley 20-Inch Mach 6 Tunnel. The intent of the overall test program is to study (both experimentally and computationally) the dynamics of the inlet unstart; however, prior to the design and fabrication of an expensive, instrumented wind-tunnel model, it was deemed necessary first to examine potential wind-tunnel blockage issues related to model sizing and to examine the adequacy of the actuation systems in accomplishing the start and unstart. The model is equipped with both a moveable cowl and aft plug. Windows in the inlet sidewalls allow limited optical access to the internal shock structure; schlieren video was used to identify inlet start and unstart. A chronology of each actuation sequence is provided in tabular form along with still frames from the schlieren video. A pitot probe monitored the freestream conditions throughout the start/unstart process to determine if there was a blockage effect due to the model start or unstart. Because the purpose of this report is to make the phase I (blockage and actuation systems) data rapidly available to the community, the data is presented largely without analysis of the internal shock interactions or the unstart process. This series of tests indicated that the model was appropriately sized for this facility and identified operability limits required first to allow the inlet to start and second to force the unstart.

  8. Scaled experiments using the helium technique to study the vehicular blockage effect on longitudinal ventilation control in tunnels

    DEFF Research Database (Denmark)

    Alva, Wilson Ulises Rojas; Jomaas, Grunde; Dederichs, Anne

    2015-01-01

    A model tunnel (1:30 compared to a standard tunnel section) with a helium-air smoke mixture was used to study the vehicular blockage effect on longitudinal ventilation smoke control. The experimental results showed excellent agreement with full-scale data and confirmed that the critical velocity ...

  9. Comparison of the accident process, radioactivity release and ground contamination between Chernobyl and Fukushima-1.

    Science.gov (United States)

    Imanaka, Tetsuji; Hayashi, Gohei; Endo, Satoru

    2015-12-01

    In this report, we have reviewed the basic features of the accident processes and radioactivity releases that occurred in the Chernobyl accident (1986) and in the Fukushima-1 accident (2011). The Chernobyl accident was a power-surge accident that was caused by a failure of control of a fission chain reaction, which instantaneously destroyed the reactor and building, whereas the Fukushima-1 accident was a loss-of-coolant accident in which the reactor cores of three units were melted by decay heat after losing the electricity supply. Although the quantity of radioactive noble gases released from Fukushima-1 exceeded the amount released from Chernobyl, the size of land area severely contaminated by (137)Cesium ((137)Cs) was 10 times smaller around Fukushima-1 compared with around Chernobyl. The differences in the accident process are reflected in the composition of the discharged radioactivity as well as in the composition of the ground contamination. Volatile radionuclides (such as (132)Te-(132)I, (131)I, (134)Cs and (137)Cs) contributed to the gamma-ray exposure from the ground contamination around Fukishima-1, whereas a greater variety of radionuclides contributed significantly around Chernobyl. When radioactivity deposition occurred, the radiation exposure rate near Chernobyl is estimated to have been 770 μGy h(-1) per initial (137)Cs deposition of 1000 kBq m(-2), whereas it was 100 μGy h(-1) around Fukushima-1. Estimates of the cumulative exposure for 30 years are 970 and 570 mGy per initial deposition of 1000 kBq m(-2) for Chernobyl and Fukusima-1, respectively. Of these exposures, 49 and 98% were contributed by radiocesiums ((134)Cs + (137)Cs) around Chernobyl and Fukushima-1, respectively. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  10. Comparison of the accident process, radioactivity release and ground contamination between Chernobyl and Fukushima-1

    Science.gov (United States)

    Imanaka, Tetsuji; Hayashi, Gohei; Endo, Satoru

    2015-01-01

    In this report, we have reviewed the basic features of the accident processes and radioactivity releases that occurred in the Chernobyl accident (1986) and in the Fukushima-1 accident (2011). The Chernobyl accident was a power-surge accident that was caused by a failure of control of a fission chain reaction, which instantaneously destroyed the reactor and building, whereas the Fukushima-1 accident was a loss-of-coolant accident in which the reactor cores of three units were melted by decay heat after losing the electricity supply. Although the quantity of radioactive noble gases released from Fukushima-1 exceeded the amount released from Chernobyl, the size of land area severely contaminated by 137Cesium (137Cs) was 10 times smaller around Fukushima-1 compared with around Chernobyl. The differences in the accident process are reflected in the composition of the discharged radioactivity as well as in the composition of the ground contamination. Volatile radionuclides (such as 132Te-132I, 131I, 134Cs and 137Cs) contributed to the gamma-ray exposure from the ground contamination around Fukishima-1, whereas a greater variety of radionuclides contributed significantly around Chernobyl. When radioactivity deposition occurred, the radiation exposure rate near Chernobyl is estimated to have been 770 μGy h−1 per initial 137Cs deposition of 1000 kBq m−2, whereas it was 100 μGy h−1 around Fukushima-1. Estimates of the cumulative exposure for 30 years are 970 and 570 mGy per initial deposition of 1000 kBq m−2 for Chernobyl and Fukusima-1, respectively. Of these exposures, 49 and 98% were contributed by radiocesiums (134Cs + 137Cs) around Chernobyl and Fukushima-1, respectively. PMID:26568603

  11. Reservoir operation schemes for water pollution accidents in Yangtze River

    Directory of Open Access Journals (Sweden)

    Xiao-kang XIN

    2012-03-01

    Full Text Available After the Three Gorges Reservoir starts running, it can not only take into consideration the interest of departments such as flood control, power generation, water supply, and shipping, but also reduce or eliminate the adverse effects of pollutants by discharge regulation. The evolution of pollutant plumes under different operation schemes of the Three Gorges Reservoir and three kinds of pollutant discharge types were calculated with the MIKE 21 AD software. The feasibility and effectiveness of the reservoir emergency operation when pollution accidents occur were investigated. The results indicate that the emergency operation produces significant effects on the instantaneous discharge type with lesser effects on the constant discharge type, the impact time is shortened, and the concentration of pollutant is reduced. Meanwhile, the results show that the larger the discharge is and the shorter the operation duration is, the more favorable the result is.

  12. Chernobyl accident and its consequences

    Energy Technology Data Exchange (ETDEWEB)

    Gittus, J.H.; Bonell, P.G.; Hicks, D.

    1987-01-01

    The USSR power reactor programme is first described. The reasons for the accident at the Chernobyl-4 RBMK nuclear reactor on 26 April 1986, the sequence of events that took place, and the immediate and long-term consequences are considered. A description of the RBMK-type reactors is given and the design changes resulting from the experience of the accident are explained. The source terms describing the details of the radioactivity release associated with the accident and the environmental consequences are covered in the last two sections of the report. Throughout the text comments referring to the UK Nuclear Installations Inspectorate Safety assessment principles have been inserted. (U.K.).

  13. [Prevention of bicycle accidents].

    Science.gov (United States)

    Zwipp, H; Barthel, P; Bönninger, J; Bürkle, H; Hagemeister, C; Hannawald, L; Huhn, R; Kühn, M; Liers, H; Maier, R; Otte, D; Prokop, G; Seeck, A; Sturm, J; Unger, T

    2015-04-01

    For a very precise analysis of all injured bicyclists in Germany it would be important to have definitions for "severely injured", "seriously injured" and "critically injured". By this, e.g., two-thirds of surgically treated bicyclists who are not registered by the police could become available for a general analysis. Elderly bicyclists (> 60 years) are a minority (10 %) but represent a majority (50 %) of all fatalities. They profit most by wearing a helmet and would be less injured by using special bicycle bags, switching on their hearing aids and following all traffic rules. E-bikes are used more and more (145 % more in 2012 vs. 2011) with 600,000 at the end of 2011 and are increasingly involved in accidents but still have a lack of legislation. So even for pedelecs 45 with 500 W and a possible speed of 45 km/h there is still no legislative demand for the use of a protecting helmet. 96 % of all injured cyclists in Germany had more than 0.5 ‰ alcohol in their blood, 86 % more than 1.1 ‰ and 59 % more than 1.7 ‰. Fatalities are seen in 24.2 % of cases without any collision partner. Therefore the ADFC calls for a limit of 1.1 ‰. Some virtual studies conclude that integrated sensors in bicycle helmets which would interact with sensors in cars could prevent collisions or reduce the severity of injury by stopping the cars automatically. Integrated sensors in cars with opening angles of 180° enable about 93 % of all bicyclists to be detected leading to a high rate of injury avoidance and/or mitigation. Hanging lamps reduce with 35 % significantly bicycle accidents for children, traffic education for children and special trainings for elderly bicyclists are also recommended as prevention tools. As long as helmet use for bicyclists in Germany rates only 9 % on average and legislative orders for using a helmet will not be in force in the near future, coming up campaigns seem to be necessary to be promoted by the Deutscher

  14. Effect of blockage of costimulatory signal on murine abortion-prone model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Fu-xi; ZHANG Yuan-yuan; LIU Run-hua; LI Shuan-ming

    2007-01-01

    Background Inhibition of the key costimulatory signals results in T cell anergy, indicating the alloantigen-specific immunologic unresponsiveness. In this study, the effect of blockage of costimulatory signal CD86 on murine abortion-prone model was studied.Methods Thirty CBA/J female mice cohabitated with DBA/2 male or BALB/c male mice were investigated. CBA/J ×DBA/2 matings were used as the abortion-prone model, and CBA/J × BALB/c matings were used as the normal pregnant model. The abortion-prone models were divided into experimental and control groups, and the normal pregnant models were set as a normal group (10 mice in each group). The mice in the experimental group were treated with anti-mouse CD86 monoclonal antibody (mAb) (100 μg) on day 4.5 of gestation, while the controls received irrelevant-isotype matched rat IgG2b. As for the normal group, nothing was given to the mice. The mice were killed on day 13.5 of gestation, embryo resorption rate and the expression of transforming growth factor β1 (TGF-β1), plasminogen activator inhibitor 1 (PAI-1), and matrix metalloproteinase 9 (MMP-9) were detected. Then the data were analyzed by Chi-square test and Fisher's exact test.Results The embryo resorption rate in the experimental (8.2%) and normal groups (7.7%) was significantly lower than that of the control (23.5%, P<0.05). No significant difference was detected between the experimental and normal groups (P>0.05). The positive expression rates of TGF-β1 and PAI-1 proteins in the experimental and normal groups were significantly higher than those in the control group (P<0.05). The positive expression rate of MMP-9 protein in the experimental and normal groups was significantly lower than that in the control group (P<0.05). No significant difference in the positive expression rates of the three proteins was detected between the experimental and normal groups (P>0.05).Conclusions Blockage of costimulatory signal CD86 at early pregnancy can treat

  15. Three Mile Island Accident Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Three Mile Island Accident Data consists of mostly upper air and wind observations immediately following the nuclear meltdown occurring on March 28, 1979, near...

  16. Instantaneous detection of spatial gradient errors in differential GNSS

    Science.gov (United States)

    Jing, Jing

    Global Navigation Satellite Systems (GNSS) have become a critical element of modern engineering and scientific applications. GPS is currently being used in the design of navigation systems for both civil and military aviation applications. Differential GPS carrier phase measurements between antennas provide a very precise measurement that is useful for these applications. In fact, ground infrastructure has already been implemented in the Ground Based Augmentation System (GBAS) to take advantage of these precise measurements for use in civil aviation. Furthermore, these antennas can also be used to detect and isolate certain signal-in-space (SIS) failures and anomalies that are hazardous to aviation applications, for example the ionospheric anomalies and ephemeris failures. This realization, in turn, has led to the development of numerous carrier-phase based monitors. One drawback of the majority of these monitors is that their performance within a given configuration is dependent on how antennas are paired to form double differences. In contrast, the null space monitor approach is developed to provide consistent detection performance regardless of how the antennas are paired which combines measurements from multiple, spatially separated ground antennas through a null space transformation. The instantaneous carrier phase monitor cannot detect all gradients due to the presence of integer ambiguities. These ambiguities cannot be resolved because the gradient magnitude is unknown a priori. Furthermore, it has been shown that the performance of such monitors is highly dependent on the reference antenna topology. The range of detectable gradients for all carrier phase monitors depends on two factors: the number of antennas and their configuration. Antenna configuration is often overlooked as a means to improve performance. and heuristic arguments typically prevail in the associated siting decisions. However. such heuristics do not provide the maximum detectable range of

  17. Nuclear fuel cycle facility accident analysis handbook

    Energy Technology Data Exchange (ETDEWEB)

    Ayer, J E; Clark, A T; Loysen, P; Ballinger, M Y; Mishima, J; Owczarski, P C; Gregory, W S; Nichols, B D

    1988-05-01

    The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the radiological risk from accidents in nuclear fuel cycle facility operations. The AAH will enable the user to calculate source term releases from accident scenarios manually or by computer. A major feature of the AAH is development of accident sample problems to provide input to source term analysis methods and transport computer codes. Sample problems and illustrative examples for different accident types are included in the AAH.

  18. Paragliding accidents in remote areas.

    Science.gov (United States)

    Fasching, G; Schippinger, G; Pretscher, R

    1997-08-01

    Paragliding is an increasingly popular hobby, as people try to find new and more adventurous activities. However, there is an increased and inherent danger with this sport. For this reason, as well as the inexperience of many operators, injuries occur frequently. This retrospective study centers on the helicopter rescue of 70 individuals in paragliding accidents. All histories were examined, and 43 patients answered a questionnaire. Nineteen (42%) pilots were injured when taking off, 20 (44%) during the flight, and six (13%) when landing. Routine and experience did not affect the prevalence of accident. Analysis of the causes of accident revealed pilot errors in all but three cases. In 34 rescue operations a landing of the helicopter near the site of the accident was possible. Half of the patients had to be rescued by a cable winch or a long rope fixed to the helicopter. Seven (10%) of the pilots suffered multiple trauma, 38 (54%) had injuries of the lower extremities, and 32 (84%) of them sustained fractures. Injuries to the spine were diagnosed in 34 cases with a fracture rate of 85%. One patient had an incomplete paraplegia. Injuries to the head occurred in 17 patients. No paraglider pilot died. The average hospitalization was 22 days, and average time of working inability was 14 weeks. Fourteen (34%) patients suffered from a permanent damage to their nerves or joints. Forty-three percent of the paragliders continued their sport despite the accident; two of them had another accident. An improved training program is necessary to lower the incidence of paragliding accidents. Optimal equipment to reduce injuries in case of accidents is mandatory. The helicopter emergency physician must perform a careful examination, provide stabilization of airways and circulation, give analgesics, splint fractured extremities, and transport the victim on a vacuum mattress to the appropriate hospital.

  19. Development of a post accident analysis model for KALIMER

    Energy Technology Data Exchange (ETDEWEB)

    Chang, W. P.; Ha, G. S.; Jeong, H. Y.; Kwon, Y. M.; Heo, S.; Lee, Y. B. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    An ultimate safety measure of the KALIMER depends on the inherent safety, which have the core maintain a negative reactivity during any accident periods. In order to secure the integrity of a fuel rod, the void reactivity feedback under sodium boiling must be analyzed. Even though the KALIMER design might not allow boiling at any circumstance, sodium boiling would be possible under HCDA (Hypothetical Core Disruptive Accident) initiating events which are represented by UTOP (Unprotected Transient Over Power), ULOF (Unprotected Loss Of Flow), ULOHS (Unprotected Loss Of Heat Sink), or sudden flow channel blockage, due to power excursion caused by the reactivity feedback. The slug and annular flow regimes tend to prevail for the boiling of a liquid-metal coolant such as sodium near the atmospheric pressure. In contrast, the bubbly flow is typical under a high pressure in light water reactors. This phenomenon difference brings to develop the present model, especially, at the onset of boiling. A few models had been developed for the sodium boiling analysis. The models such as those in the HOMSEP-2 and SAS series are classified into relatively detailed models. Both models are usually called a multiple-bubble slug ejection model. Some simpler models are also introduced to evade either parameter sensitivities or a mathematical complexity associated with those rigorous models. The present model based on the multiple-bubble slug ejection model. It allows a finite number (N) of bubbles, separated by liquid slugs, in a channel. Boiling occurs at a user specified superheat, and a generated vapor is modeled to fill the whole cross section of the coolant channel except for a static liquid film left on the cladding or/and structure surfaces. The model also assumes a vapor with one uniform pressure. The present analysis is focused on the behavior of early sodium boiling after ULOHS.

  20. Severe accident analysis using dynamic accident progression event trees

    Science.gov (United States)

    Hakobyan, Aram P.

    In present, the development and analysis of Accident Progression Event Trees (APETs) are performed in a manner that is computationally time consuming, difficult to reproduce and also can be phenomenologically inconsistent. One of the principal deficiencies lies in the static nature of conventional APETs. In the conventional event tree techniques, the sequence of events is pre-determined in a fixed order based on the expert judgments. The main objective of this PhD dissertation was to develop a software tool (ADAPT) for automated APET generation using the concept of dynamic event trees. As implied by the name, in dynamic event trees the order and timing of events are determined by the progression of the accident. The tool determines the branching times from a severe accident analysis code based on user specified criteria for branching. It assigns user specified probabilities to every branch, tracks the total branch probability, and truncates branches based on the given pruning/truncation rules to avoid an unmanageable number of scenarios. The function of a dynamic APET developed includes prediction of the conditions, timing, and location of containment failure or bypass leading to the release of radioactive material, and calculation of probabilities of those failures. Thus, scenarios that can potentially lead to early containment failure or bypass, such as through accident induced failure of steam generator tubes, are of particular interest. Also, the work is focused on treatment of uncertainties in severe accident phenomena such as creep rupture of major RCS components, hydrogen burn, containment failure, timing of power recovery, etc. Although the ADAPT methodology (Analysis of Dynamic Accident Progression Trees) could be applied to any severe accident analysis code, in this dissertation the approach is demonstrated by applying it to the MELCOR code [1]. A case study is presented involving station blackout with the loss of auxiliary feedwater system for a

  1. Flood hazards along the Toutle and Cowlitz rivers, Washington, from a hypothetical failure of Castle Lake blockage

    Science.gov (United States)

    Laenen, Antonius; Orzol, L.L.

    1987-01-01

    A recent evaluation of groundwater and material in the blockage impounding Castle Lake shows that the blockage is potentially unstable against failure from piping due to heave and internal erosion when groundwater levels are seasonally high. There is also a remote possibility that a 6.8 or greater magnitude earthquake could occur in the Castle Lake area when groundwater levels are critically high. If this situation occurs, the debris blockage that confines Castle Lake could breach from successive slope failure with liquefaction of a portion of the blockage. A dam-break computer model was used to simulate discharge through a hypothetical breach in the Castle Lake blockage that could be caused by failure by heave, internal erosion, or liquefaction. Approximately 18,500 acre-ft of stored water would be released from an assumed breach that fully developed to a 1,000-ft width over a 15-minute time period. The resulting flood, incorporating 3.4 x 10 to the 6th power cu yd of the debris blockage, would reach a peak magnitude of 1,500,000 cu ft/s (cubic feet per second). The flood is also assumed to incorporate an additional 137x10 to the 6th power cu yd of saturated debris material from downstream deposits. Flow is considered to be hyperconcentrated with sediment throughout the course of the flood. The hypothetical hyperconcentrated flow is routed downstream, superimposed on normal winter flood flows by use of a one-dimensional unsteady-state numerical streamflow simulation model. From a starting magnitude of 1,500,000 cu ft/s, the peak increases to 2,100,000 cu ft/s at N-1 Dam (12 mi downstream) and attenuates to 1,200,000 cu ft/s at Kid Valley (25 mi downstream) , to 100,000 cu ft/s at Longview and the confluence of the Columbia River (65 mi downstream). From time of breach, the flood peak would take 2.2 hr to reach Toutle, 3.8 hr to reach Castle Rock, and 8.5 hr to reach Longview. Communities of Toutle , Castle Rock, Kelso, and Longview would experience extreme to

  2. Application of organic acid Composite Blockage Removal Technology%低碳复合有机酸解堵技术

    Institute of Scientific and Technical Information of China (English)

    陈锐; 余海棠

    2014-01-01

    义正油田长6油层酸敏性强,矿物中的高岭石和绿泥石含量较高,不宜采用常规酸化解堵措施。该区油层伤害以敏感性伤害、措施及开采过程中的有机、无机物堵塞为主。低碳复合有机酸主要有缓速酸、有机溶剂、氧化剂等组成,依靠缓释酸的溶蚀性,有机溶剂的溶解性及其它成分的协同作用,达到解堵的目的。室内评价结果表明,低碳复合有机酸可以有效解除油井的高分子聚合物、无机垢的堵塞。在合理选井的基础上,将其应用于现场,取得了良好的效果。%Yizheng oilfield C6 oil reservoir is acid sensitivity,and the main reservoir minerals of C6 oil reservoir are kaolinite and chlorite,thus,the conventional acidizing blockage removal technology is not suitable for C6 oil reservoir. Reservoir damage is mainly sensibility damage,pluged by organic and inorganic matter produced by stimulation and exploitation process in this area. Co-organic acid is mainly compose of retarded acid,organic solvent,oxidant,etc. Depending on dissolution by slowly releasing acids,solubility in organic solvents and synergism of other components to achieve the goal of blockage removal.The test indoor results showed that organic acid composite blockage removal technology can remove blockage produced by high molecule polymer,inorganic scale effectively.The organic acid composite blockage removal technology has been applied to the scene to remove the reservoir blockage successfully and it has made a good effect on the basis of selecting oil well correctly.

  3. Differential blockage of two types of potassium channels in the crab giant axon.

    Science.gov (United States)

    Soria, B; Arispe, N; Quinta-Ferreira, M E; Rojas, E

    1985-01-01

    Measurements were made of the kinetic and steady-state characteristics of the potassium conductance in the giant axon of the crabs Carcinus maenas and Cancer pagirus. The conductance increase during depolarizing voltage-clamp pulses was analyzed assuming that two separate types of potassium channels exist in these axons (M.E. Quinta-Ferreira, E. Rojas and N. Arispe, J. Membrane Biol. 66:171-181, 1982). It is shown here that, with small concentrations of conventional K+-channel blockers, it is possible to differentially inhibit these channels. The potassium channels with activation and fast inactivation gating (m3h, Hodgkin-Huxley kinetics) were blocked by external application of 4 amino-pyridine (4-AP). The potassium channels with standard gating (n4, Hodgkin-Huxley kinetics) were preferentially inhibited by externally applied tetraethylammonium (TEA). The differential blockage of the two types of potassium conductance changes suggests that they represent two different populations of potassium channels. It is further shown here that blocking the early transient conductance increase leads to the inhibition of the repetitive electrical activity induced by constant depolarizing current injection in fibers from Cardisoma guanhumi.

  4. Blockage of the pyrimidine biosynthetic pathway affects riboflavin production in Ashbya gossypii.

    Science.gov (United States)

    Silva, Rui; Aguiar, Tatiana Q; Domingues, Lucília

    2015-01-10

    The Ashbya gossypii riboflavin biosynthetic pathway and its connection with the purine pathway have been well studied. However, the outcome of genetic alterations in the pyrimidine pathway on riboflavin production by A. gossypii had not yet been assessed. Here, we report that the blockage of the de novo pyrimidine biosynthetic pathway in the recently generated A. gossypii Agura3 uridine/uracil auxotrophic strain led to improved riboflavin production on standard agar-solidified complex medium. When extra uridine/uracil was supplied, the production of riboflavin by this auxotroph was repressed. High concentrations of uracil hampered this (and the parent) strain growth, whereas excess uridine favored the A. gossypii Agura3 growth. Considering that the riboflavin and the pyrimidine pathways share the same precursors and that riboflavin overproduction may be triggered by nutritional stress, we suggest that overproduction of riboflavin by the A. gossypii Agura3 may occur as an outcome of a nutritional stress response and/or of an increased availability in precursors for riboflavin biosynthesis, due to their reduced consumption by the pyrimidine pathway.

  5. The Frenet and Darboux Instantaneous Rotation for Curves on Space-Like Surface

    OpenAIRE

    Kılıç, Osman; Çalışkan, Ali

    1996-01-01

    In this paper , considering the Darboux instantaneous rotation vector of a solid perpendicular trihedron in the Minkowski 3-space R13, the Frenet instantaneous rotation vector was stated for the Frenet trihedron of a space -like space curve (c) with the binormal b being a time-like vector. The Darboux derivative formulas and the Darboux instantaneous rotation vector were found when the curve (c) is on a space -like surface. A fundamental relation, as a base for the geometry of space-like surf...

  6. Development and application of flexible substrate sensors in instantaneous heat flux measurement

    Institute of Scientific and Technical Information of China (English)

    XU Duo; GU JiaHua; WU Song

    2009-01-01

    A new type of sensor with the flexible substrate is introduced.It is applicable in measuring instanta-neous heat flux on the model surface in a hypersonic shock tunnel.The working principle,structure and manufacture process of the sensor are presented.The substrate thickness and the dynamic re-sponse parameter of the sensor are calculated.Because this sensor was successfully used in meas-uring the instantaneous heat flux on the surface of a flat plate in a detonation-driven shock tunnel,it may be effective in measuring instantaneous heat flux on the model surface.

  7. Accident tolerant fuel analysis

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis [Idaho National Laboratory; Chichester, Heather [Idaho National Laboratory; Johns, Jesse [Texas A& M University; Teague, Melissa [Idaho National Laboratory; Tonks, Michael Idaho National Laboratory; Youngblood, Robert [Idaho National Laboratory

    2014-09-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about light water reactor design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway research and development (R&D) is to support plant decisions for risk-informed margins management by improving economics and reliability, and sustaining safety, of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced ''RISMC toolkit'' that enables more accurate representation of NPP safety margin. In order to carry out the R&D needed for the Pathway, the Idaho National Laboratory is performing a series of case studies that will explore methods- and tools-development issues, in addition to being of current interest in their own right. One such study is a comparative analysis of safety margins of plants using different fuel cladding types: specifically, a comparison between current-technology Zircaloy cladding and a notional ''accident-tolerant'' (e.g., SiC-based) cladding. The present report begins the process of applying capabilities that are still under development to the problem of assessing new fuel designs. The approach and lessons learned from this case study will be included in future Technical Basis Guides produced by the RISMC Pathway. These guides will be the mechanism for developing the specifications for RISMC tools and for defining how plant

  8. [Accidents of fulguration].

    Science.gov (United States)

    Virenque, C; Laguerre, J

    1976-01-01

    Fulguration, first electric accident in which the man was a victim, is to day better known. A clap of thunder is decomposed in two elements: lightning, and thunder. Lightning is caused by an electrical discharge, either within a cloud, or between two clouds, or, above all, between a cloud and the surface of the ground. Experimental equipments owned by the French Electricity Company and by the Atomic Energy Commission, have allowed to photograph lightnings and to measure certain physical characteristics (Intensity variable between 25 to 100 kA, voltage variable between 20 to 1 000 kV). The frequency of storms was learned: the isokeraunic level, in France, is about 20, meaning that thunder is heard twenty days during one year. Man may be stricken by thunder by direct hit, by sudden bursting, by earth current, or through various conductors. The electric charge which reached him may go to the earth directly by contact with the ground or may dissipate in the air through a bony promontory (elbow). The total number of victims, "wounded" or deceased, is not now known by statistics. Death comes by insulation breakdown of one of several anatomic cephalic formations: skull, meninx, brain. Many various lesions may happen in survivors: loss of consciousness, more or less long, sensorial or motion deficiencies. All these signs are momentary and generally reversible. Besides one may observe much more intense lesions on the skin: burns and, over all, characteristic aborescence (skin effect by high frequency current). The heart is protected, contrarily to what happens with industrial electrocution. The curative treatment is merely symptomatic : reanimation, surgery for burns or associated traumatic lesions. A prevention is researched to help the lonely man, in the country or in the mountains in the houses (lightning conductor, Faraday cage), in vehicles (aircraft, cars, ships). The mysterious and unforseeable character of lightning still stays, leaving a door opened for numerous

  9. Accident Tolerant Fuel Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Curtis Smith; Heather Chichester; Jesse Johns; Melissa Teague; Michael Tonks; Robert Youngblood

    2014-09-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about light water reactor design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway research and development (R&D) is to support plant decisions for risk-informed margins management by improving economics and reliability, and sustaining safety, of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced “RISMC toolkit” that enables more accurate representation of NPP safety margin. In order to carry out the R&D needed for the Pathway, the Idaho National Laboratory is performing a series of case studies that will explore methods- and tools-development issues, in addition to being of current interest in their own right. One such study is a comparative analysis of safety margins of plants using different fuel cladding types: specifically, a comparison between current-technology Zircaloy cladding and a notional “accident-tolerant” (e.g., SiC-based) cladding. The present report begins the process of applying capabilities that are still under development to the problem of assessing new fuel designs. The approach and lessons learned from this case study will be included in future Technical Basis Guides produced by the RISMC Pathway. These guides will be the mechanism for developing the specifications for RISMC tools and for defining how plant decision makers should propose and

  10. Numerical simulation of radioisotope's dependency on containment performance for large dry PWR containment under severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Mehboob, Khurram, E-mail: khurramhrbeu@gmail.com [College of Nuclear Science and Technology, Harbin Engineering University, 145-31 Nantong Street, Nangang District, Harbin, Heilongjiang 150001 (China); Xinrong, Cao [College of Nuclear Science and Technology, Harbin Engineering University, 145-31 Nantong Street, Nangang District, Harbin, Heilongjiang 150001 (China); Ahmed, Raheel [College of Automation, Harbin Engineering University, 145-31 Nantong Street, Nangang District, Harbin, Heilongjiang 150001 (China); Ali, Majid [College of Nuclear Science and Technology, Harbin Engineering University, 145-31 Nantong Street, Nangang District, Harbin, Heilongjiang 150001 (China)

    2013-09-15

    Highlights: • Calculation and comparison of activity of BURN-UP code with ORIGEN2 code. • Development of SASTC computer code. • Radioisotopes dependency on containment ESFs. • Mitigation in atmospheric release with ESFs operation. • Variation in radioisotopes source term with spray flow and pH value. -- Abstract: During the core melt accidents large amount of fission products can be released into the containment building. These fission products escape into the environment to contribute in accident source term. The mitigation in environmental release is demanded for such radiological consequences. Thus, countermeasures to source term, mitigations of release of radioactivity have been studied for 1000 MWe PWR reactor. The procedure of study is divided into five steps: (1) calculation and verification of core inventory, evaluated by BURN-UP code, (2) containment modeling based on radioactivity removal factors, (3) selection of potential accidents initiates the severe accident, (4) calculation of release of radioactivity, (5) study the dependency of release of radioactivity on containment engineering safety features (ESFs) inducing mitigation. Loss of coolant accident (LOCA), small break LOCA and flow blockage accidents (FBA) are selected as initiating accidents. The mitigation effect of ESFs on source term has been studied against ESFs performance. Parametric study of release of radioactivity has been carried out by modeling and simulating the containment parameters in MATLAB, which takes BURN-UP outcomes as input along with the probabilistic data. The dependency of iodine and aerosol source term on boric and caustic acid spray has been determined. The variation in source term mitigation with the variation of containment spray flow rate and pH values have been studied. The variation in containment retention factor (CRF) has also been studied with the ESF performance. A rapid decrease in source term is observed with the increase in pH value.

  11. PWR FLECHT SEASET 163-Rod Bundle Flow Blockage Task data report. NRC/EPRI/Westinghouse report No. 13, August-October 1982

    Energy Technology Data Exchange (ETDEWEB)

    Loftus, M J; Hochreiter, L E; McGuire, M F; Valkovic, M M

    1983-10-01

    This report presents data from the 163-Rod Bundle Blow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Systems Effects and Separate Effects Test Program (FLECHT SEASET). The task consisted of forced and gravity reflooding tests utilizing electrical heater rods with a cosine axial power profile to simulate PWR nuclear core fuel rod arrays. These tests were designed to determine effects of flow blockage and flow bypass on reflooding behavior and to aid in the assessment of computational models in predicting the reflooding behavior of flow blockage in rod bundle arrays.

  12. Heat Removal Performance in accordance with the Location of the Half-blockage of the Inlet Openings of Concrete Storage Cask

    Energy Technology Data Exchange (ETDEWEB)

    Bang, K. S.; Yu, S. H.; Lee, J. C.; Lee, S. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The heat transfer rate to the ambient atmosphere by convective air through a passive heat removal system under off-normal conditions reached 87.4 %. Therefore, the half-blockage of the inlet openings has a relatively small effect on the maximum temperature and temperature distributions. A temperature difference in accordance with the location of the half-blockage of the inlet openings was not found. Therefore, the influence of the direction of the half-blockage of the inlet openings reaching the heat removal performance was estimated to be minimal.

  13. Instantaneous thermal modeling of the DC-link capacitor in PhotoVoltaic systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Ma, Ke; Wang, Huai

    2015-01-01

    Capacitors have been witnessed as one of the weak points in grid-connected PhotoVoltaic (PV) applications, and thus efforts have been devoted to the design of reliable DC-link capacitors in PV applications. Since the hot-spot temperature of the capacitor is one of the failure inducers......, instantaneous thermal modeling approaches considering mission profiles for the DC-link capacitor in single-phase PV systems are explored in this paper. These thermal modelling approaches are based on: a) fast Fourier transform, b) look-up tables, and c) ripple current reconstruction. Moreover, the thermal...... modelling approaches for the DC-link capacitors take into account the instantaneous thermal characteristics, which are more challenging to the capacitor reliability during operation. Such instantaneous thermal modeling approaches enable a translation of instantaneous capacitor power losses to capacitor...

  14. Digital instantaneous frequency measurement technique utilising high-speed ADC’s and FPGA’s

    CSIR Research Space (South Africa)

    Herselman, PL

    2006-02-27

    Full Text Available This paper presents the Digital Instantaneous Frequency Measurement (DIFM) technique, which can measure the carrier frequency of a received waveform within a fraction of a microsecond. The resulting frequency range, resolution and accuracy...

  15. Geomagnetic Components D, H, X, Y, Z, and R 10-second Instantaneous Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are generated as part of the International Magnetospheric Study. The file consists of 10-second instantaneous measurements for the geomagnetic components...

  16. Instantaneous Gradient Based Dual Mode Feed-Forward Neural Network Blind Equalization Algorithm

    Directory of Open Access Journals (Sweden)

    Ying Xiao

    2013-01-01

    Full Text Available To further improve the performance of feed-forward neural network blind equalization based on Constant Modulus Algorithm (CMA cost function, an instantaneous gradient based dual mode between Modified Constant Modulus Algorithm (MCMA and Decision Directed (DD algorithm was proposed. The neural network weights change quantity of the adjacent iterative process is defined as instantaneous gradient. After the network converges, the weights of neural network to achieve a stable energy state and the instantaneous gradient would be zero. Therefore dual mode algorithm can be realized by criterion which set according to the instantaneous gradient. Computer simulation results show that the dual mode feed-forward neural network blind equalization algorithm proposed in this study improves the convergence rate and convergence precision effectively, at the same time, has good restart and tracking ability under channel burst interference condition.

  17. Assessment of movement distribution in the lumbar spine using the instantaneous axis of rotation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ki Won [Trine University, Angola (Indonesia)

    2014-12-15

    The position of the torso and the magnitude of exertion are thought to influence the distribution pattern of intervertebral movements within the lumbar spine. Abnormal intervertebral movements have been correlated with the risk of spine injuries. Since the capability to measure movement distribution within the lumbar spine noninvasively is limited, a convenient method to diagnose joint motion function was proposed. The goal of this research was to test the efficacy of the instantaneous axis of rotation for assessment of the distribution of movement within the lumbar spine. The proposed method was evaluated in the bio mechanical model. The results showed that the location of instantaneous axis of rotation lowered with increased trunk exertion force, and slightly moved higher with increased trunk angle. Recognizing that abnormal location of the instantaneous axis of rotation correlated with spinal pain, these results suggest potential the location of the instantaneous axis of rotation relates to the risk of low back pain on distributed spinal kinematics.

  18. Effect of Local Nasal Immunotherapy on Nasal Blockage in Pollen-Induced Allergic Rhinitis of Guinea Pigs

    OpenAIRE

    Takeshi Nabe; Kayoko Kubota; Nobuaki Mizutani; Masanori Fujii; Tetsuya Terada; Hiroshi Takenaka; Shigekatsu Kohno

    2008-01-01

    Background: As a non-injection route for immunotherapy, local nasal immunotherapy has been examined in allergic rhinitis patients. However, it is unclear how the immunotherapy affects sneezing, biphasic nasal blockage and nasal hyperresponsiveness. Thus, we evaluated the therapeutic effects of nasal immunotherapy on the symptoms of guinea pig allergic rhinitis. Additionally, we also evaluated whether the immunotherapy relieved pollen-induced allergic conjunctivitis. Methods: Sensitized ani...

  19. Automatic tea service machine with instantaneous cooling unit; Shunkan reikyaku kiko tosai jido kyuchaki

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T.; Nishiyama, A. [Fuji Denki Reiki Co. Ltd., Tokyo (Japan)

    1999-08-10

    The market of automatic tea service machines demands sanitation, reduction in time required for pouring tea, feeding the material, cleaning the inside of the machine, the maintenance and service of the machine, and excellent design. To meet these demands, Fuji Electric has changed the former configuration and components for functions and has developed a new series of instantaneous automatic tea service machines based on a new concept. This paper outlines the advantages of the instantaneous cooling tank and improvements in handling. (author)

  20. An analysis of the instantaneous floating point amplifier in DFS-V seismic recording system

    Energy Technology Data Exchange (ETDEWEB)

    Benji, W.

    1987-04-01

    Instantaneous floating point amplifier is a key unit in digital seismic system. The detailed description is given of circuits, functions and mechanisms of major constituents of the instantaneous floating point amplifier in DFS-V seismic system; and the process of gain adjustment of signal sample is analysed in the paper. A comment on its distinctive zero drift correction method is made. The concrete measure is put forward to cope with the problem in digital offset filtering taken in DFS-V system.

  1. Existence of mild solutions to partial differential equations with non-instantaneous impulses

    Directory of Open Access Journals (Sweden)

    Pengyu Chen

    2016-09-01

    Full Text Available In this article, we study the existence of piecewise-continuous mild solutions for the initial value problems for a class of semilinear evolution equations. These equations have non-instantaneous impulses in Banach spaces and the corresponding solution semigroup is noncompact. We assume that the nonlinear term satisfies certain local growth condition and a noncompactness measure condition. Also we assume the non-instantaneous impulsive functions satisfy some Lipschitz conditions. An example is given to illustrate our results.

  2. Modeling of The hERG K+ Channel Blockage Using Online Chemical Database and Modeling Environment (OCHEM).

    Science.gov (United States)

    Li, Xiao; Zhang, Yuan; Li, Huanhuan; Zhao, Yong

    2017-08-30

    Human ether-a-go-go related gene (hERG) K+ channel plays an important role in cardiac action potential. Blockage of hERG channel may result in long QT syndrome (LQTS), even cause sudden cardiac death. Many drugs have been withdrawn from the market because of the serious hERG-related cardiotoxicity. Therefore, it is quite essential to estimate the chemical blockage of hERG in the early stage of drug discovery. In this study, a diverse set of 3721 compounds with hERG inhibition data was assembled from literature. Then, we make full use of the Online Chemical Modeling Environment (OCHEM), which supplies rich machine learning methods and descriptor sets, to build a series of classification models for hERG blockage. We also generated two consensus models based on the top-performing individual models. The consensus models performed much better than the individual models both on 5-fold cross validation and external validation. Especially, consensus model II yielded the prediction accuracy of 89.5 % and MCC of 0.670 on external validation. This result indicated that the predictive power of consensus model II should be stronger than most of the previously reported models. The 17 top-performing individual models and the consensus models and the data sets used for model development are available at https://ochem.eu/article/103592. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Long-term fertility prognosis following selective salpingography and tubal catheterization in women with proximal tubal blockage.

    Science.gov (United States)

    Papaioannou, Spyros; Afnan, Masoud; Girling, Alan J; Coomarasamy, Aravinthan; Ola, Borarinde; Olufowobi, Olufemi; McHugo, Josephine M; Hammadieh, Nahed; Sharif, Khaldoun

    2002-09-01

    The possibility of conception following selective salpingography and tubal catheterization is believed to decline sharply a few months after the procedure. This observation may be due to the relatively small number of patients and short follow-up of previous studies. Furthermore, couples with other causes of infertility apart from proximal tubal blockage have usually been excluded. Survival analysis of conceptions of 218 consecutive infertile women with proximal tubal blockage who underwent selective salpingography and tubal catheterization was performed. There were no exclusion criteria. Follow-up ranged from 16 to 56 months. A total of 47.2% of spontaneous conceptions and 43.2% of all conceptions, apart from those achieved by IVF or ICSI treatments, occurred after the first 12 months following selective salpingography and tubal catheterization. The decline in the possibility of pregnancy during the study period (conception hazard rate) was only minimal. In a population of infertile women with proximal tubal blockage, a significant proportion of conceptions occur after the first 12 months following selective salpingography and tubal catheterization. The presence of any additional causes of infertility in the couple should not be regarded as an absolute contraindication to the procedure.

  4. Effect of road blockages on local air pollution during the Hong Kong protests and its implications for air quality management.

    Science.gov (United States)

    Brimblecombe, Peter; Ning, Zhi

    2015-12-01

    Roadside air quality in urban areas is largely affected by the traffic emissions. Changes in emissions and transport control policy are often assumed to yield benefits in air quality, but have often not always been effective in producing perceptible improvements due to the complexity of meteorological conditions. This study evaluates the air quality before, during and after a temporary roadway blockage event in Hong Kong that took place during Hong Kong protests from late September to mid-December, 2014. The local regulatory air quality monitoring data from both roadside and general ambient stations were used to assess the impact of roadway blockages on the air quality. There was a public perception of improved air quality, but analysis of the data shows the changes can be difficult to discern. This study showed some benefits deriving from road blockages on the local air quality, but the impact was not always apparent because of seasonal variation in meteorological conditions and synoptic transport of pollutants. The finding suggests care is required before making policy changes based on claimed benefits of shifting transport routes. The study highlights the needs to remove seasonal and meteorological change when examining air pollution data to develop strategies to improve air quality.

  5. Blockage of complement regulators in the conjunctiva and within the eye leads to massive inflammation and iritis.

    Science.gov (United States)

    Bardenstein, D S; Cheyer, C J; Lee, C; Cocuzzi, E; Mizuno, M; Okada, N; Medof, M E

    2001-12-01

    The open environment of the eye is continuously subject to an influx of foreign agents that can activate complement. Decay-accelerating factor (DAF), membrane cofactor protein (MCP) and CD59 are regulators that protect self-cells from autologous complement activation on their surfaces. They are expressed in the eye at unusually high levels but their physiological importance in this site is unstudied. In the rat, a structural analogue termed 5I2 antigen (5I2 Ag) has actions overlapping DAF and MCP. In this investigation, we injected F(ab')2 fragments of 5I2 mAb into the conjunctiva and aqueous humor, in the latter case with and without concomitant blockage of CD59. Massive neutrophilic infiltration of the stroma and iris resulted upon blocking 5I2 Ag activity. Frank necrosis of the iris occurred upon concomitant intraocular blockage of CD59. C3b was identified immunohistochemically, and minimal effects were seen in complement-depleted animals and in those treated with non-relevant antibody. The finding that blockage of 5I2 Ag function in periocular tissues and within the eye causes intense conjunctival inflammation and iritis demonstrates the importance of intrinsic complement regulators in protecting ocular tissues from spontaneous or bystander attack by autologous complement.

  6. Blockage of P2X7 attenuates acute lung injury in mice by inhibiting NLRP3 inflammasome.

    Science.gov (United States)

    Wang, Shuang; Zhao, Jijun; Wang, Hongyue; Liang, Yingjie; Yang, Niansheng; Huang, Yuefang

    2015-07-01

    NLRP3 inflammasome is engaged in the inflammatory response during acute lung injury (ALI). Purinergic receptor P2X7 has been reported to be upstream of NLRP3 activation. However, the therapeutic implication of P2X7 in ALI remains to be explored. The present study used lipopolysaccharide (LPS)-induced mouse model to investigate the therapeutic potential of P2X7 blockage in ALI. Our results showed that P2X7/NLRP3 inflammasome pathway was significantly upregulated in the lungs of ALI mice as compared with control mice. P2X7 antagonist A438079 suppressed NLRP3/ASC/caspase 1 activation, production of IL-1β, IL-17A and IFN-γ and neutrophil infiltration but not the production of IL-10, resulting in a significant amelioration of lung injury. Moreover, blockage of P2X7 significantly inhibited NLRP3 inflammasome activation and IL-1β production in bone marrow derived macrophages. Similar results were obtained using another P2X7 inhibitor brilliant blue G (BBG) in vivo. Thus, pharmacological blockage of P2X7/NLRP3 pathway can be considered as a potential therapeutic strategy in patients with ALI.

  7. Accident knowledge and emergency management

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, B.; Groenberg, C.D.

    1997-03-01

    The report contains an overall frame for transformation of knowledge and experience from risk analysis to emergency education. An accident model has been developed to describe the emergency situation. A key concept of this model is uncontrolled flow of energy (UFOE), essential elements are the state, location and movement of the energy (and mass). A UFOE can be considered as the driving force of an accident, e.g., an explosion, a fire, a release of heavy gases. As long as the energy is confined, i.e. the location and movement of the energy are under control, the situation is safe, but loss of confinement will create a hazardous situation that may develop into an accident. A domain model has been developed for representing accident and emergency scenarios occurring in society. The domain model uses three main categories: status, context and objectives. A domain is a group of activities with allied goals and elements and ten specific domains have been investigated: process plant, storage, nuclear power plant, energy distribution, marine transport of goods, marine transport of people, aviation, transport by road, transport by rail and natural disasters. Totally 25 accident cases were consulted and information was extracted for filling into the schematic representations with two to four cases pr. specific domain. (au) 41 tabs., 8 ills.; 79 refs.

  8. Radioactive materials transport accident analysis

    Energy Technology Data Exchange (ETDEWEB)

    McSweeney, T.I.; Maheras, S.J.; Ross, S.B. [Battelle Memorial Inst. (United States)

    2004-07-01

    Over the last 25 years, one of the major issues raised regarding radioactive material transportation has been the risk of severe accidents. While numerous studies have shown that traffic fatalities dominate the risk, modeling the risk of severe accidents has remained one of the most difficult analysis problems. This paper will show how models that were developed for nuclear spent fuel transport accident analysis can be adopted to obtain estimates of release fractions for other types of radioactive material such as vitrified highlevel radioactive waste. The paper will also show how some experimental results from fire experiments involving low level waste packaging can be used in modeling transport accident analysis with this waste form. The results of the analysis enable an analyst to clearly show the differences in the release fractions as a function of accident severity. The paper will also show that by placing the data in a database such as ACCESS trademark, it is possible to obtain risk measures for transporting the waste forms along proposed routes from the generator site to potential final disposal sites.

  9. Nuclear accident dosimetry intercomparison studies.

    Science.gov (United States)

    Sims, C S

    1989-09-01

    Twenty-two nuclear accident dosimetry intercomparison studies utilizing the fast-pulse Health Physics Research Reactor at the Oak Ridge National Laboratory have been conducted since 1965. These studies have provided a total of 62 different organizations a forum for discussion of criticality accident dosimetry, an opportunity to test their neutron and gamma-ray dosimetry systems under a variety of simulated criticality accident conditions, and the experience of comparing results with reference dose values as well as with the measured results obtained by others making measurements under identical conditions. Sixty-nine nuclear accidents (27 with unmoderated neutron energy spectra and 42 with eight different shielded spectra) have been simulated in the studies. Neutron doses were in the 0.2-8.5 Gy range and gamma doses in the 0.1-2.0 Gy range. A total of 2,289 dose measurements (1,311 neutron, 978 gamma) were made during the intercomparisons. The primary methods of neutron dosimetry were activation foils, thermoluminescent dosimeters, and blood sodium activation. The main methods of gamma dose measurement were thermoluminescent dosimeters, radiophotoluminescent glass, and film. About 68% of the neutron measurements met the accuracy guidelines (+/- 25%) and about 52% of the gamma measurements met the accuracy criterion (+/- 20%) for accident dosimetry.

  10. Measurement of instantaneous viscoelastic properties by impedance-frequency curve of the ventricle.

    Science.gov (United States)

    Koiwa, Y; Hashiguchi, R; Ohyama, T; Isoyama, S; Satoh, S; Suzuki, H; Takishima, T

    1986-04-01

    We developed a method for estimating the instantaneous viscoelastic properties of the left ventricle (LV). This impedance-curve method is based on the instantaneous impedance-frequency curve of the left ventricle generated by a rapidly oscillating mechanical impulse applied to the epicardial surface of the heart. The theoretical basis of the method and experimentally obtained instantaneous impedance-frequency curves were examined to evaluate the validity of our basic assumptions. Using these impedance-curve data, we calculated the instantaneous viscoelastic properties of the LV during the cardiac cycle. The impedance curve shows a configuration that is almost the same as the theoretical curve based on the assumption that an RCL (R, resistor; C, capacitor; L, inductor) parallel circuit is the electrical analog for the LV. The impedance curve varied moment by moment during the development of instantaneous LV pressure. The elastic and viscous coefficients, calculated from the impedance curve, increased with increase of LV pressure. We concluded that the impedance-curve method can delineate the instantaneous viscoelastic properties of the ventricle (especially of the ventricular myocardium).

  11. The child accident repeater: a review.

    Science.gov (United States)

    Jones, J G

    1980-04-01

    The child accident repeater is defined as one who has at least three accidents that come to medical attention within a year. The accident situation has features in common with those of the child who has a single accident through simple "bad luck", but other factors predispose him to repeated injury. In the child who has a susceptible personality, a tendency for accident repetition may be due to a breakdown in adjustment to a stressful environment. Prevention of repeat accidents should involve the usual measures considered appropriate for all children as well as an attempt to provide treatment of significant maladjustment and modification of a stressful environment.

  12. Hindsight Bias in Cause Analysis of Accident

    Institute of Scientific and Technical Information of China (English)

    Atsuo Murata; Yasunari Matsushita

    2014-01-01

    It is suggested that hindsight becomes an obstacle to the objective investigation of an accident, and that the proper countermeasures for the prevention of such an accident is impossible if we view the accident with hindsight. Therefore, it is important for organizational managers to prevent hindsight from occurring so that hindsight does not hinder objective and proper measures to be taken and this does not lead to a serious accident. In this study, a basic phenomenon potentially related to accidents, that is, hindsight was taken up, and an attempt was made to explore the phenomenon in order to get basically insights into the prevention of accidents caused by such a cognitive bias.

  13. Severe accident simulation at Olkiuoto

    Energy Technology Data Exchange (ETDEWEB)

    Tirkkonen, H.; Saarenpaeae, T. [Teollisuuden Voima Oy (TVO), Olkiluoto (Finland); Cliff Po, L.C. [Micro-Simulation Technology, Montville, NJ (United States)

    1995-09-01

    A personal computer-based simulator was developed for the Olkiluoto nuclear plant in Finland for training in severe accident management. The generic software PCTRAN was expanded to model the plant-specific features of the ABB Atom designed BWR including its containment over-pressure protection and filtered vent systems. Scenarios including core heat-up, hydrogen generation, core melt and vessel penetration were developed in this work. Radiation leakage paths and dose rate distribution are presented graphically for operator use in diagnosis and mitigation of accidents. Operating on an graphically for operator use in diagnosis and mitigation of accidents. Operating on an 486 DX2-66, PCTRAN-TVO achieves a speed about 15 times faster than real-time. A convenient and user-friendly graphic interface allows full interactive control. In this paper a review of the component models and verification runs are presented.

  14. Road characteristics and bicycle accidents.

    Science.gov (United States)

    Nyberg, P; Björnstig, U; Bygren, L O

    1996-12-01

    In Umeå, Sweden, defects in the physical road surface contributed to nearly half of the single bicycle accidents. The total social cost of these injuries to people amount to at least SEK 20 million (SEK 60,000 or about USD 8,500 per accident), which corresponds to the estimated loss of "eight life equivalents a year". Improved winter maintenance seems to have the greatest injury prevention potential and would probably reduce the number of injuries considerably, whereas improved road quality and modification of kerbs would reduce the most severe injuries. A local traffic safety program should try to prevent road accidents instead of handling the consequences of them. In accordance with Parliament decisions on traffic we would like to see increased investment in measures favoring bicycle traffic, where cycling is seen as a solution, not as a problem.

  15. Bathtub immersion accidents involving children.

    Science.gov (United States)

    Pearn, J; Nixon, J

    1977-02-12

    A review of 19 consecutive serious bathtub immersion accidents (11 survivals, 8 fatalities) is presented. In all instances, consciousness was lost in the water. Unlike other childhood accidents which usually show a male predominance, the sexes are equally affected. The modal age is 11 months. Six separate causes of bath drownings and near-drownings have been identified, and in 14 of the 19 accidents, two or more causes were operating concurrently. Median estimated immersion time for survivals was four minutes, and five minutes for fatalities. The median depth of water was eight inches. An 'at risk' profile for home bathtub drownings is presented; this includes the youngest or second youngest child of a large family, a family of grade 4 to 7 sociooccupational status (congalton) and a family in which routine is temporarily broken.

  16. Internal Accident Report on EDH

    CERN Multimedia

    SC Department

    2006-01-01

    The A2 Safety Code requires that, the Internal Accident Report form must be filled in by the person concerned or any witness to ensure that all the relevant services are informed. Please note that an electronic version of this form has been elaborated in collaboration with SC-IE, HR-OPS-OP and IT-AIS. Whenever possible, the electronic form shall be used. The relative icon is available on the EDH Desktop, Other tasks page, under the Safety heading, or directly here: https://edh.cern.ch/Document/Accident/. If you have any questions, please contact the SC Secretariat, tel. 75097 Please notice that the Internal Accident Report is an integral part of the Safety Code A2 and does not replace the HS50.

  17. Fukushima accident study using MELCOR

    Institute of Scientific and Technical Information of China (English)

    Randall O Gauntt

    2013-01-01

    The accidents at the Fukushima Daiichi nuclear power station stunned the world as the sequences played out over severals days and videos of hydrogen explosions were televised as they took place.The accidents all resulted in severe damage to the reactor cores and releases of radioactivity to the environment despite heroic measures had taken by the operating personnel.The following paper provides some background into the development of these accidents and their root causes,chief among them,the prolonged station blackout conditions that isolated the reactors from their ultimate heat sink — the ocean.The interpretations given in this paper are summarized from a recently completed report funded by the United States Department of Energy (USDOE).

  18. How to reduce the number of accidents

    CERN Multimedia

    2012-01-01

    Among the safety objectives that the Director-General has established for CERN in 2012 is a reduction in the number of workplace accidents.   The best way to prevent workplace accidents is to learn from experience. This is why any accident, fire, instance of pollution, or even a near-miss, should be reported using the EDH form that can be found here. All accident reports are followed up. The departments investigate all accidents that result in sick leave, as well as all the more common categories of accidents at CERN, essentially falls (slipping, falling on stairs, etc.), regardless of whether or not they lead to sick leave. By studying the accident causes that come to light in this way, it is possible to take preventive action to avoid such accidents in the future. If you have any questions, the HSE Unit will be happy to answer them. Contact us at safety-general@cern.ch. HSE Unit

  19. Trismus: An unusual presentation following road accident

    Directory of Open Access Journals (Sweden)

    Thakur Jagdeep

    2007-01-01

    Full Text Available Trismus due to trauma usually follows road accidents leading to massive faciomaxillary injury. In the literature there is no report of a foreign body causing trismus following a road accident, this rare case is an exception. We present a case of isolated presentation of trismus following a road accident. This case report stresses on the thorough evaluation of patients presenting with trismus following a road accident.

  20. The Physics of Traffic Accidents

    Science.gov (United States)

    Knight, Peter

    1975-01-01

    Shows how physics can be used to analyze and prevent traffic accidents by determining critical speeds on curves, the behavior of motor cycles and stability of articulated vehicles, and the visibility that is needed to make a minor road junction safe. (MLH)

  1. Work Accidents and Professional Diseases

    Directory of Open Access Journals (Sweden)

    Doru Hauptmann

    2009-10-01

    Full Text Available The major accident is defined as “any event occurred, like an emission of dangerous materials or agents, which emerges from uncontrolled evolutions along the exploitation of any objective that leads to the immediate or delayed occurrence of serious dangers with impact over human health or over the environment, inside or outside the objective in which are involved one or more than one dangerous materials”.The dangerous phenomenon is a potential source of harms. In the ambit of industrial risks of accidental origins, this expression more frequently refers to physical phenomena like conflagrations, explosions, toxic gases dispersion, etc.Any accident scenario relates itself to the potential effects at the level of environmental “targets”. In the case of major accidents, we can distinguish the following categories of “targets”: human (employees of the objective, working or resident people in the nearby of the emplacement; the installation or equipments that may stay at the origin of the accidents (dangerous equipments; certain all-important equipments to ensure the safety level of the installation (critical security equipments: control rooms, civil fire brigade headquarters, etc; goods and structures situated in the installation’ environment (ground water, rivers, soil, flora, fauna.

  2. New technology for accident prevention

    Energy Technology Data Exchange (ETDEWEB)

    Byne, P. [Shiftwork Solutions, Vancouver, BC (Canada)

    2006-07-01

    This power point presentation examined the effects of fatigue in the workplace and presented 3 technologies designed to prevent or monitor fatigue. The relationship between mental fatigue, circadian rhythms and cognitive performance was explored. Details of vigilance related degradations in the workplace were presented, as well as data on fatigue-related accidents and a time-line of meter-reading errors. It was noted that the direct cause of the Exxon Valdez disaster was sleep deprivation. Fatigue related accidents during the Gulf War were reviewed. The effects of fatigue on workplace performance include impaired logical reasoning and decision-making; impaired vigilance and attention; slowed mental operations; loss of situational awareness; slowed reaction time; and short cuts and lapses in optional or self-paced behaviours. New technologies to prevent fatigue-related accidents include (1) the driver fatigue monitor, an infra-red camera and computer that tracks a driver's slow eye-lid closures to prevent fatigue related accidents; (2) a fatigue avoidance scheduling tool (FAST) which collects actigraphs of sleep activity; and (3) SAFTE, a sleep, activity, fatigue and effectiveness model. refs., tabs., figs.

  3. Corporate Cost of Occupational Accidents

    DEFF Research Database (Denmark)

    Rikhardsson, Pall M.; Impgaard, M.

    2004-01-01

    The systematic accident cost analysis (SACA) project was carried out during 2001 by The Aarhus School of Business and PricewaterhouseCoopers Denmark with financial support from The Danish National Working Environment Authority. Its focused on developing and testing a method for evaluating...

  4. Crime, accidents and social control

    NARCIS (Netherlands)

    Junger, Marianne; Terlouw, Gert-Jan; van der Heijden, Peter G.M.

    1995-01-01

    This paper addresses to questions. (1) Is there a demonstrable relation between accidents and crime, does this relation hold for each type of crime and each means of transport, and does it subsist after controlling for age and gender? (2) Can social control theory explain involvements in both

  5. Detection and analysis of accident black spots with even small accident figures.

    NARCIS (Netherlands)

    Oppe, S.

    1982-01-01

    Accident black spots are usually defined as road locations with high accident potentials. In order to detect such hazardous locations we have to know the probability of an accident for a traffic situation of some kind, or the mean number of accidents for some unit of time. In almost all procedures

  6. Detection and analysis of accident black spots with even small accident figures.

    NARCIS (Netherlands)

    Oppe, S.

    1982-01-01

    Accident black spots are usually defined as road locations with high accident potentials. In order to detect such hazardous locations we have to know the probability of an accident for a traffic situation of some kind, or the mean number of accidents for some unit of time. In almost all procedures

  7. Intersection layout, traffic volumes and accidents.

    NARCIS (Netherlands)

    Poppe, F.

    1988-01-01

    This paper reports on the accident research carried out as a part of a large project started in 1983. For this accident research an inventory was made of a large number of intersections.Recorded were layout features, accident data and estimates of traffic volumes. Attention will be given to the

  8. 48 CFR 836.513 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Accident prevention. 836... prevention. The contracting officer must insert the clause at 852.236-87, Accident Prevention, in solicitations and contracts for construction that contain the clause at FAR 52.236-13, Accident Prevention....

  9. 48 CFR 1836.513 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Accident prevention. 1836... 1836.513 Accident prevention. The contracting officer must insert the clause at 1852.223-70, Safety and Health, in lieu of FAR clause 52.236-13, Accident Prevention, and its Alternate I....

  10. 48 CFR 636.513 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Accident prevention. 636... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 636.513 Accident prevention. (a) In... contracting activities shall insert DOSAR 652.236-70, Accident Prevention, in lieu of FAR clause...

  11. Barriers to learning from incidents and accidents

    NARCIS (Netherlands)

    Dechy, N.; Dien, Y.; Drupsteen, L.; Felicio, A.; Cunha, C.; Roed-Larsen, S.; Marsden, E.; Tulonen, T.; Stoop, J.; Strucic, M.; Vetere Arellano, A.L.; Vorm, J.K.J. van der; Benner, L.

    2015-01-01

    This document provides an overview of knowledge concerning barriers to learning from incidents and accidents. It focuses on learning from accident investigations, public inquiries and operational experience feedback, in industrial sectors that are exposed to major accident hazards. The document disc

  12. Analysing truck position data to study roundabout accident risk

    OpenAIRE

    Kamla, Jwan Jameel Shekh Mohammed

    2016-01-01

    In order to reduce accident risk, highway authorities prioritise maintenance budgets partly based upon previous accident history. However, as accident rates have continued to fall in most contexts, this approach has become problematic as accident ‘black spots’ have been treated and the number of accidents at any individual site has fallen. Another way of identifying sites of higher accident risk might be to identify near-miss accidents (where an accident nearly happened, but was avoided), whi...

  13. The Werner and Bloom syndrome proteins help resolve replication blockage by converting (regressed) holliday junctions to functional replication forks.

    Science.gov (United States)

    Machwe, Amrita; Karale, Rajashree; Xu, Xioahua; Liu, Yilun; Orren, David K

    2011-08-16

    Cells cope with blockage of replication fork progression in a manner that allows DNA synthesis to be completed and genomic instability minimized. Models for resolution of blocked replication involve fork regression to form Holliday junction structures. The human RecQ helicases WRN and BLM (deficient in Werner and Bloom syndromes, respectively) are critical for maintaining genomic stability and thought to function in accurate resolution of replication blockage. Consistent with this notion, WRN and BLM localize to sites of blocked replication after certain DNA-damaging treatments and exhibit enhanced activity on replication and recombination intermediates. Here we examine the actions of WRN and BLM on a special Holliday junction substrate reflective of a regressed replication fork. Our results demonstrate that, in reactions requiring ATP hydrolysis, both WRN and BLM convert this Holliday junction substrate primarily to a four-stranded replication fork structure, suggesting they target the Holliday junction to initiate branch migration. In agreement, the Holliday junction binding protein RuvA inhibits the WRN- and BLM-mediated conversion reactions. Importantly, this conversion product is suitable for replication with its leading daughter strand readily extended by DNA polymerases. Furthermore, binding to and conversion of this Holliday junction are optimal at low MgCl(2) concentrations, suggesting that WRN and BLM preferentially act on the square planar (open) conformation of Holliday junctions. Our findings suggest that, subsequent to fork regression events, WRN and/or BLM could re-establish functional replication forks to help overcome fork blockage. Such a function is highly consistent with phenotypes associated with WRN- and BLM-deficient cells.

  14. Research on Nonlinear Characteristics of Image Measurement System for Instantaneous Concentration Field

    Directory of Open Access Journals (Sweden)

    Wu Jing

    2013-06-01

    Full Text Available Quantitative measurement on instantaneous concentration field not only can provide scientific methods for people measuring environment wind tunnel, but also can provide important data for solving convection--diffusion problem in practical project. The established large environment and wind engineering wind tunnel needs to develop the measurement system of instantaneous concentration field in order to study concentration field of environmental pollution diffusion. Based on collecting, analyzing and selecting a large number of literatures, the paper comprehensively studies the image measurement of instantaneous concentration field, and develops the complete software and hardware system. And the developed measurement system is used to measure the results, and the nonlinear characteristics of instable concentration field are studied. Combined with experimental fluid mechanics, information technology, optical scattering and imaging theory, the paper makes quantitative calculation on instability of concentration field from an experimental point of view, which provides an important experimental result for using numerical method to explore the instability of concentration field.

  15. Instantaneous charge state of Uranium projectiles in fully ionized plasmas from energy loss experiments

    CERN Document Server

    Morales, Roberto; Casas, David

    2016-01-01

    The instantaneous charge state of uranium ions traveling through a fully ionized hydrogen plasma has been theoretically studied and compared with one of the first energy loss experiments in plasmas, carried out at GSI-Darmstadt by Hoffmann \\textit{et al.} in the 90's. For this purpose, two different methods to estimate the instantaneous charge state of the projectile have been employed: (1) rate equations using ionization and recombination cross sections, and (2) equilibrium charge state formulas for plasmas. Also, the equilibrium charge state has been obtained using these ionization and recombination cross sections, and compared with the former equilibrium formulas. The equilibrium charge state of projectiles in plasmas is not always reached, it depends mainly on the projectile velocity and the plasma density. Therefore, a non-equilibrium or an instantaneous description of the projectile charge is necessary. The charge state of projectile ions cannot be measured, except after exiting the target, and experime...

  16. Possibilities to identify engine combustion model parameters by analysis of the instantaneous crankshaft angular speed

    Directory of Open Access Journals (Sweden)

    Popović Slobodan J.

    2014-01-01

    Full Text Available In this paper, novel method for obtaining information about combustion process in individual cylinders of a multi-cylinder Spark Ignition Engine based on instantaneous crankshaft angular velocity is presented. The method is based on robust box constrained Levenberg-Marquardt minimization of nonlinear Least Squares given for measured and simulated instantaneous crankshaft angular speed which is determined from the solution of the engine dynamics torque balance equation. Combination of in-house developed comprehensive Zero-Dimensional Two-Zone SI engine combustion model and analytical friction loss model in angular domain have been applied to provide sensitivity and error analysis regarding Wiebe combustion model parameters, heat transfer coefficient and compression ratio. The analysis is employed to evaluate the basic starting assumption and possibility to provide reliable combustion analysis based on instantaneous engine crankshaft angular speed. [Projekat Ministarstva nauke Republike Srbije, br. NPEE-290025 and TR-14074

  17. Instantaneous Click Chemistry by a Copper-Containing Polymeric-Membrane-Installed Microflow Catalytic Reactor.

    Science.gov (United States)

    Yamada, Yoichi M A; Ohno, Aya; Sato, Takuma; Uozumi, Yasuhiro

    2015-11-23

    The copper(I)-catalyzed Huisgen cycloaddition (azide-alkyne cycloaddition) is an important reaction in click chemistry that ideally proceeds instantaneously. An instantaneous Huisgen cycloaddition has been developed that uses a novel catalytic dinuclear copper complex-containing polymeric membrane-installed microflow device. A polymeric membranous copper catalyst was prepared from poly(4-vinylpyridine), copper(II) sulfate, sodium chloride, and sodium ascorbate at the interface of two laminar flows inside microchannels. Elucidation of the structure by XANES, EXAFS, and elemental analysis, as well as second-order Møller-Plesset perturbation theory (MP2) calculations and density functional theory (DFT) calculations assigned the local structure near Cu as a μ-chloro dinuclear Cu(I) complex. The microflow device promotes the instantaneous click reaction of a variety of alkynes and organic azides to afford the corresponding triazoles in quantitative yield.

  18. Comparative study of instantaneous frequency based methods for leak detection in pipeline networks

    Science.gov (United States)

    Ghazali, M. F.; Beck, S. B. M.; Shucksmith, J. D.; Boxall, J. B.; Staszewski, W. J.

    2012-05-01

    Methods of pressure transient analysis can be seen as a promising, accurate and low-cost tool for leak and feature detection in pipelines. Various systems have been developed by several groups of researchers in recent years. Such techniques have been successfully demonstrated under laboratory conditions but are not yet established for use with real field test data. The current paper presents a comparative study of instantaneous frequency analysis techniques based on pressure transients recorded within a live distribution network. The instantaneous frequency of the signals are analysed using the Hilbert transform (HT), the Normalised Hilbert transform (NHT), Direct Quadrature (DQ), Teager Energy Operator (TEO) and Cepstrum. This work demonstrates the effectiveness of the instantaneous frequency analysis in detecting a leaks and other features within the network. NHT and DQ allowed for the identification of the approximate location of leaks. The performance TEO is moderate, with Cepstrum being the worst performing method.

  19. [Hanggliding accidents. Distribution of injuries and accident analysis].

    Science.gov (United States)

    Ballmer, F T; Jakob, R P

    1989-12-01

    Paragliding--a relatively new sport to Switzerland--brought 23 patients with 48 injuries (38% lower limb and 29% spinal) within a period of 8 months to the Inselspital University hospital in Berne. The aim of the study in characterizing these injuries is to formulate some guidelines towards prevention. With over 90% of accidents occurring at either take off or landing, emphasis on better training for the beginner is proposed with strict guidelines for the more experienced pilot flying in unfavourable conditions.

  20. Preliminary Modeling of Accident Tolerant Fuel Concepts under Accident Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gamble, Kyle A.; Hales, Jason D.

    2016-12-01

    The catastrophic events that occurred at the Fukushima-Daiichi nuclear power plant in 2011 have led to widespread interest in research of alternative fuels and claddings that are proposed to be accident tolerant. Thus, the United States Department of Energy through its NEAMS (Nuclear Energy Advanced Modeling and Simulation) program has funded an Accident Tolerant Fuel (ATF) High Impact Problem (HIP). The ATF HIP is funded for a three-year period. The purpose of the HIP is to perform research into two potential accident tolerant concepts and provide an in-depth report to the Advanced Fuels Campaign (AFC) describing the behavior of the concepts, both of which are being considered for inclusion in a lead test assembly scheduled for placement into a commercial reactor in 2022. The initial focus of the HIP is on uranium silicide fuel and iron-chromium-aluminum (FeCrAl) alloy cladding. Utilizing the expertise of three national laboratory participants (INL, LANL, and ANL) a comprehensive mulitscale approach to modeling is being used including atomistic modeling, molecular dynamics, rate theory, phase-field, and fuel performance simulations. In this paper, we present simulations of two proposed accident tolerant fuel systems: U3Si2 fuel with Zircaloy-4 cladding, and UO2 fuel with FeCrAl cladding. The simulations investigate the fuel performance response of the proposed ATF systems under Loss of Coolant and Station Blackout conditions using the BISON code. Sensitivity analyses are completed using Sandia National Laboratories’ DAKOTA software to determine which input parameters (e.g., fuel specific heat) have the greatest influence on the output metrics of interest (e.g., fuel centerline temperature). Early results indicate that each concept has significant advantages as well as areas of concern. Further work is required prior to formulating the proposition report for the Advanced Fuels Campaign.

  1. Blockage Corrections for Three-Dimensional-Flow Closed-Throat Wind Tunnels, with Consideration of the Effect of Compressibility

    Science.gov (United States)

    Herriot, J. G.

    1951-01-01

    Theoretical blockage corrections are presented for a body of revolution and for a three-dimensional, unswept wing in a circular or rectangular wind tunnel. The theory takes account of the effects of the wake and of the compressibility of the fluid, and is based on the assumption that the dimensions of the model are small in comparison with those of the tunnel throat. Formulas are given for correcting a number of the quantities, such as dynamic pressure and Mach number, measured in wind tunnel tests. The report presents a summary and unification of the existing literature on the subject

  2. The instantaneous rate dependence in low temperature laboratory rock friction and rock deformation experiments

    Science.gov (United States)

    Beeler, N.M.; Tullis, T.E.; Kronenberg, A.K.; Reinen, L.A.

    2007-01-01

    Earthquake occurrence probabilities that account for stress transfer and time-dependent failure depend on the product of the effective normal stress and a lab-derived dimensionless coefficient a. This coefficient describes the instantaneous dependence of fault strength on deformation rate, and determines the duration of precursory slip. Although an instantaneous rate dependence is observed for fracture, friction, crack growth, and low temperature plasticity in laboratory experiments, the physical origin of this effect during earthquake faulting is obscure. We examine this rate dependence in laboratory experiments on different rock types using a normalization scheme modified from one proposed by Tullis and Weeks [1987]. We compare the instantaneous rate dependence in rock friction with rate dependence measurements from higher temperature dislocation glide experiments. The same normalization scheme is used to compare rate dependence in friction to rock fracture and to low-temperature crack growth tests. For particular weak phyllosilicate minerals, the instantaneous friction rate dependence is consistent with dislocation glide. In intact rock failure tests, for each rock type considered, the instantaneous rate dependence is the same size as for friction, suggesting a common physical origin. During subcritical crack growth in strong quartzofeldspathic and carbonate rock where glide is not possible, the instantaneous rate dependence measured during failure or creep tests at high stress has long been thought to be due to crack growth; however, direct comparison between crack growth and friction tests shows poor agreement. The crack growth rate dependence appears to be higher than the rate dependence of friction and fracture by a factor of two to three for all rock types considered. Copyright 2007 by the American Geophysical Union.

  3. Exploratory analysis of Spanish energetic mining accidents.

    Science.gov (United States)

    Sanmiquel, Lluís; Freijo, Modesto; Rossell, Josep M

    2012-01-01

    Using data on work accidents and annual mining statistics, the paper studies work-related accidents in the Spanish energetic mining sector in 1999-2008. The following 3 parameters are considered: age, experience and size of the mine (in number of workers) where the accident took place. The main objective of this paper is to show the relationship between different accident indicators: risk index (as an expression of the incidence), average duration index for the age and size of the mine variables (as a measure of the seriousness of an accident), and the gravity index for the various sizes of mines (which measures the seriousness of an accident, too). The conclusions of this study could be useful to develop suitable prevention policies that would contribute towards a decrease in work-related accidents in the Spanish energetic mining industry.

  4. The dominance of accidents caused by banalities

    DEFF Research Database (Denmark)

    Jørgensen, Kirsten

    . Nevertheless, the fact is that the simpler accidents normally caused by what might be regarded as banalities occur at a much higher frequencies and with many more fatalities and invalidities than any of what are usually regarded as the most dangerous kinds of accidents. In depth analysis of national statistics...... on accidents could reveal the kind of accidents we are talking about, where they happen, to whom, how, and what can be done about them. This would require a special registration system of the events leading up to the accident. The main results for the four most frequent types of accident will be described...... as an example of how much information such systems can offer in general for the work of accident prevention in more traditional and common enterprises....

  5. Testing Jitter on PLL Clocks Based on Analysis of Instantaneous Phase

    Institute of Scientific and Technical Information of China (English)

    ZHU Yanqing; HE Yigang; FANG Gefeng; YANG Hui; QI Shaozhong; LIU Hui

    2007-01-01

    A novel method based on the analysis of instantaneous phase is proposed to extract the jitter on phase-locked loops output clock. The method utilizes the Hilbert transform to extend the real signal of PLLs output into an analytic signal, and the implementation of Hilbert transform is based on the Fourier transform windowed with Hamming window. Then, the jitter of clock is extracted from the instantaneous phase of analytic signal. The experimental results of simulations validate that the proposed method can effectively extract the jitter on PLL clock, and it has better performance by comparing the sinusoidal jitter extraction results with the other methods.

  6. Three-dimensional instantaneous velocity field measurement using digital holography microscope

    Indian Academy of Sciences (India)

    Dhananjay Kumar Singh; P K Panigrahi

    2014-02-01

    In the present study, a digital holography microscope has been developed to study instantaneous 3D velocity field in a square channel of 1000 × 1000 2 cross-section. The flow field is seeded with polystyrene microspheres of size $d_p = 2.1$ m. The volumetric flow rate is set equal to 20 l/min. The instantaneous 3D velocity field is obtained by correlating the particles obtained from the 3D numerical reconstruction of holograms using particle tracking velocimetry (PTV).

  7. On properties of the deterministic turbulence and reproducibility of its instantaneous and statistical characteristics

    Directory of Open Access Journals (Sweden)

    Vladimir I. Borodulin

    2014-01-01

    Full Text Available As known from previous studies, the deterministic turbulence (DeTu is a post-transitional flow that is turbulent according to the generally accepted statistical characteristics but possesses, meanwhile, a significant degree of determinism, i.e., reproducibility of its instantaneous structure. It is found that the DeTu can occur in those cases when transition is caused by convective instabilities; in boundary layers, in particular. The present paper is devoted to a brief description of history of discovering the DeTu phenomenon, as well as to some recent advance in investigation of instantaneous and statistical properties of such turbulent boundary layer flows.

  8. Application of Ultrasonic Technique for Measurement of Instantaneous Burn Rate of Solid Propellants .

    Directory of Open Access Journals (Sweden)

    Desh Deepak

    1998-04-01

    Full Text Available The ultrasonic pulse-echo technique has been applied for the measurement of instantaneous burnrate of aluminised composite solid propellants. The tests have been carried out on end-burning 30 mmthick propellant specimens at nearly constant pressure of about 1.9 MPa. Necessary software forpost-test data processing and instantaneous burn rate computations have been developed. The burnrates measured by the ultrasonic technique have been compared with those obtained from ballisticevaluation motor tests on propellant from the same mix. An accuracy of about +- 1 per cent ininstantaneous burn rate measurements and reproducibility of results have been demonstrated byapplying ultrasonic technique.

  9. Instantaneous Bethe-Salpeter Equation and Its Analog: Breit-like Equation

    Institute of Scientific and Technical Information of China (English)

    CHANG Chao-Hsi; CHEN Jiao-Kai

    2005-01-01

    We take the (μ士e干) system as an example, but restrict ourselves to highlight the states with quantum number JP = 0-, to explore the different contents of the instantaneous Bethe-Salpeter (BS) equation and its analog,the relativistic version of Breit equation, by solving them exactly. The results show that the two equations are not equivalent, although they are analogous. Furthermore, since the Breit equation contains extra un-physical solutions,so we point out that it should be abandoned if one wishes to have an accurate description of the bound states for the instantaneous interacting binding systems.

  10. Practical approaches in accident analysis

    Science.gov (United States)

    Stock, M.

    An accident analysis technique based on successive application of structural response, explosion dynamics, gas cloud formation, and plant operation failure mode models is proposed. The method takes into account the nonideal explosion characteristic of a deflagration in the unconfined cloud. The resulting pressure wave differs significantly from a shock wave and the response of structures like lamp posts and walls can differ correspondingly. This gives a more realistic insight into explosion courses than a simple TNT-equivalent approach.

  11. The consequences of Chernobyl accident

    Directory of Open Access Journals (Sweden)

    Ion Chioșilă

    2016-12-01

    Full Text Available These days marks 30 years since the Chernobyl nuclear accident, followed by massive radioactive contamination of the environment and human in Belarus, Ukraine and Russia, and resulted in many deaths among people who intervened to decrease the effects of the nuclear disaster. The 26 April 1986 nuclear accident contaminated all European countries, but at a much lower level, without highlighted consequences on human health. In special laboratories, the main radionuclides (I-131, Cs-137, Cs-134 and Sr-90 were also analyzed in Romania from environmental samples, food, even human subjects. These radionuclides caused the population to receive a low dose of about 1 mSv in 1986 that is half of the dose of the natural background radiation (2.4 mSv per year. As in all European countries (excluding Ukraine, Belarus and Russia this dose of about 1 mSv fell rapidly by 1990, reaching levels close to ones before the accident at the nuclear tests.

  12. [Multicenter paragliding accident study 1990].

    Science.gov (United States)

    Lautenschlager, S; Karli, U; Matter, P

    1992-01-01

    During the period from 1.1.90 until 31.12.90, 86 injuries associated with paragliding were analyzed in a prospective study in 12 different Swiss hospitals with reference to causes, patterns, and frequencies. The injuries showed a mean score of over 2 and were classified as severe. Most frequent spine injuries (36%) and lesions of the lower extremity (35%) with a high risk of the ankles were diagnosed. One accident was fatal. 60% of the accidents happened during landing, 26% during launching and 14% during flight. Half of the pilots were affected during their primary training course. Most accidents were caused by inflight error of judgement--especially incorrect estimation of wind conditions--and further the choice of unfavourable landing sites. In contrast to previous injury-reports, only one equipment failure could be noted, but often the equipment was not corresponding with the experience and the weight of the pilot. To reduce the frequency of paragliding-injuries an accurate choice of equipment and an increased attention to environmental factors is mandatory. Furthermore an education-program regarding the attitude and intelligence of the pilot should be included in training courses.

  13. Medical consequences of Chernobyl accident

    Directory of Open Access Journals (Sweden)

    Galstyan I.A.

    2015-12-01

    Full Text Available Aim: to study the long-term effects of acute radiation syndrome (ARS, developed at the victims of the Chernobyl accident. Material and Methods. 237 people were exposed during the accident, 134 of them were diagnosed with ARS. Dynamic observation implies a thorough annual examination in a hospital. Results. In the first 1.5-2 years after the ARS mean group indices of peripheral blood have returned to normal. However, many patients had transient expressed moderate cytopenias. Granulocytopenia, thrombocytopenia, lymphopenia and erythropenia were the most frequently observed things during the first 5 years after the accident. After 5 years their occurences lowered. In 11 patients the radiation cataract was detected. A threshold dose for its development is a dose of 3.2 Gy Long-term effects of local radiation lesions (LRL range from mild skin figure smoothing to a distinct fibrous scarring, contractures, persistently recurrent late radiation ulcers. During all years of observation we found 8 solid tumors, including 2 thyroid cancers. 5 hematologic diseases were found. During 29 years 26 ARS survivors died of various causes. Conclusion. The health of ones with long-term ARS effects is determined by the evolution of the LRL effects on skin, radiation cataracts, hema-tological diseases and the accession of of various somatic diseases, not caused by radiation.

  14. Transient behavior of a scaled RCCS test facility under postulated fault and accident scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Lisowski, Darius D.; Hu, Rui; Bucknor, Matthew D.; Gerardi, Craig D.; Farmer, Mitch T.

    2016-01-01

    Tests were performed on the Natural convection Shutdown heat removal Test Facility (NSTF) to simulate design basis accident and postulated fault scenarios. Residing at Argonne National Laboratory, the NSTF stands nearly 26-m in total height and reflects a ½ scale reactor cavity cooling system (RCCS) for high temperature gas cooled reactors. The following manuscript details three test conditions performed on the experimental test facility. The first simulated the reactor pressure vessel (RPV) boundary condition during depressurized conduction cool down accident with small primary leak, and was repeated during both winter and summer seasons. The second examined a short-circuit break between the inlet and outlet flow paths, and was performed in three incremental stages of nominal flow area break size. The third and final test case studied system behavior with varying amounts of cooling channel blockages, up to and including 50% flow areas. Nominal component temperatures, heat removal performance, and system stability will be presented to characterize the behavior at these conditions.

  15. Electromagnetic system for detection and localization of miners caught in mine accidents

    Science.gov (United States)

    Pronenko, Vira; Dudkin, Fedir

    2016-12-01

    The profession of a miner is one of the most dangerous in the world. Among the main causes of fatalities in underground coal mines are the delayed alert of the accident and the lack of information regarding the actual location of the miners after the accident. In an emergency situation (failure or destruction of underground infrastructure), personnel search behind and beneath blockage needs to be performed urgently. However, none of the standard technologies - radio-frequency identification (RFID), Digital Enhanced Cordless Telecommunications (DECT), Wi-Fi, emitting cables, which use the stationary technical devices in mines - provide information about the miners location with the necessary precision. The only technology that is able to provide guaranteed delivery of messages to mine personnel, regardless of their location and under any destruction in the mine, is low-frequency radio technology, which is able to operate through the thickness of rocks even if they are wet. The proposed new system for miner localization is based on solving the inverse problem of determining the magnetic field source coordinates using the data of magnetic field measurements. This approach is based on the measurement of the magnetic field radiated by the miner's responder beacon using two fixed and spaced three-component magnetic field receivers and the inverse problem solution. As a result, a working model of the system for miner's beacon search and localization (MILES - MIner's Location Emergency System) was developed and successfully tested. This paper presents the most important aspects of this development and the results of experimental tests.

  16. Instantaneous and time-averaged dispersion and measurement models for estimation theory applications with elevated point source plumes

    Science.gov (United States)

    Diamante, J. M.; Englar, T. S., Jr.; Jazwinski, A. H.

    1977-01-01

    Estimation theory, which originated in guidance and control research, is applied to the analysis of air quality measurements and atmospheric dispersion models to provide reliable area-wide air quality estimates. A method for low dimensional modeling (in terms of the estimation state vector) of the instantaneous and time-average pollutant distributions is discussed. In particular, the fluctuating plume model of Gifford (1959) is extended to provide an expression for the instantaneous concentration due to an elevated point source. Individual models are also developed for all parameters in the instantaneous and the time-average plume equations, including the stochastic properties of the instantaneous fluctuating plume.

  17. Temporal Statistic of Traffic Accidents in Turkey

    Science.gov (United States)

    Erdogan, S.; Yalcin, M.; Yilmaz, M.; Korkmaz Takim, A.

    2015-10-01

    Traffic accidents form clusters in terms of geographic space and over time which themselves exhibit distinct spatial and temporal patterns. There is an imperative need to understand how, where and when traffic accidents occur in order to develop appropriate accident reduction strategies. An improved understanding of the location, time and reasons for traffic accidents makes a significant contribution to preventing them. Traffic accident occurrences have been extensively studied from different spatial and temporal points of view using a variety of methodological approaches. In literature, less research has been dedicated to the temporal patterns of traffic accidents. In this paper, the numbers of traffic accidents are normalized according to the traffic volume and the distribution and fluctuation of these accidents is examined in terms of Islamic time intervals. The daily activities and worship of Muslims are arranged according to these time intervals that are spaced fairly throughout the day according to the position of the sun. The Islamic time intervals are never been used before to identify the critical hour for traffic accidents in the world. The results show that the sunrise is the critical time that acts as a threshold in the rate of traffic accidents throughout Turkey in Islamic time intervals.

  18. [Accidents in travellers - the hidden epidemic].

    Science.gov (United States)

    Walz, Alexander; Hatz, Christoph

    2013-06-01

    The risk of malaria and other communicable diseases is well addressed in pre-travel advice. Accidents are usually less discussed. Thus, we aimed at assessing accident figures for the Swiss population, based on data of the register from 2004 to 2008 of the largest Swiss accident insurance organization (SUVA). More than 139'000 accidents over 5 years showed that 65 % of the accidents overseas are injuries, and 24 % are caused by poisoning or harm by cold, heat or air pressure. Most accidents happened during leisure activities or sports. More than one third of the non-lethal and more than 50 % of the fatal accidents happened in Asia. More than three-quarters of non-lethal accidents take place in people between 25 and 54 years. One out of 74 insured persons has an accident abroad per year. Despite of many analysis short-comings of the data set with regard to overseas travel, the figures document the underestimated burden of disease caused by accidents abroad and should affect the given pre-health advice.

  19. TEMPORAL STATISTIC OF TRAFFIC ACCIDENTS IN TURKEY

    Directory of Open Access Journals (Sweden)

    S. Erdogan

    2015-10-01

    Full Text Available Traffic accidents form clusters in terms of geographic space and over time which themselves exhibit distinct spatial and temporal patterns. There is an imperative need to understand how, where and when traffic accidents occur in order to develop appropriate accident reduction strategies. An improved understanding of the location, time and reasons for traffic accidents makes a significant contribution to preventing them. Traffic accident occurrences have been extensively studied from different spatial and temporal points of view using a variety of methodological approaches. In literature, less research has been dedicated to the temporal patterns of traffic accidents. In this paper, the numbers of traffic accidents are normalized according to the traffic volume and the distribution and fluctuation of these accidents is examined in terms of Islamic time intervals. The daily activities and worship of Muslims are arranged according to these time intervals that are spaced fairly throughout the day according to the position of the sun. The Islamic time intervals are never been used before to identify the critical hour for traffic accidents in the world. The results show that the sunrise is the critical time that acts as a threshold in the rate of traffic accidents throughout Turkey in Islamic time intervals.

  20. Severe Accident Recriticality Analyses (SARA)

    Energy Technology Data Exchange (ETDEWEB)

    Frid, W. [Swedish Nuclear Power Inspectorate, Stockholm (Sweden); Hoejerup, F. [Risoe National Lab. (Denmark); Lindholm, I.; Miettinen, J.; Puska, E.K. [VTT Energy, Helsinki (Finland); Nilsson, Lars [Studsvik Eco and Safety AB, Nykoeping (Sweden); Sjoevall, H. [Teoliisuuden Voima Oy (Finland)

    1999-11-01

    Recriticality in a BWR has been studied for a total loss of electric power accident scenario. In a BWR, the B{sub 4}C control rods would melt and relocate from the core before the fuel during core uncovery and heat-up. If electric power returns during this time-window unborated water from ECCS systems will start to reflood the partly control rod free core. Recriticality might take place for which the only mitigating mechanisms are the Doppler effect and void formation. In order to assess the impact of recriticality on reactor safety, including accident management measures, the following issues have been investigated in the SARA project: 1. the energy deposition in the fuel during super-prompt power burst, 2. the quasi steady-state reactor power following the initial power burst and 3. containment response to elevated quasi steady-state reactor power. The approach was to use three computer codes and to further develop and adapt them for the task. The codes were SIMULATE-3K, APROS and RECRIT. Recriticality analyses were carried out for a number of selected reflooding transients for the Oskarshamn 3 plant in Sweden with SIMULATE-3K and for the Olkiluoto 1 plant in Finland with all three codes. The core state initial and boundary conditions prior to recriticality have been studied with the severe accident codes SCDAP/RELAP5, MELCOR and MAAP4. The results of the analyses show that all three codes predict recriticality - both superprompt power bursts and quasi steady-state power generation - for the studied range of parameters, i. e. with core uncovery and heat-up to maximum core temperatures around 1800 K and water flow rates of 45 kg/s to 2000 kg/s injected into the downcomer. Since the recriticality takes place in a small fraction of the core the power densities are high which results in large energy deposition in the fuel during power burst in some accident scenarios. The highest value, 418 cal/g, was obtained with SIMULATE-3K for an Oskarshamn 3 case with reflooding

  1. Temporal pattern recognition based on instantaneous spike rate coding in a simple auditory system.

    Science.gov (United States)

    Nabatiyan, A; Poulet, J F A; de Polavieja, G G; Hedwig, B

    2003-10-01

    Auditory pattern recognition by the CNS is a fundamental process in acoustic communication. Because crickets communicate with stereotyped patterns of constant frequency syllables, they are established models to investigate the neuronal mechanisms of auditory pattern recognition. Here we provide evidence that for the neural processing of amplitude-modulated sounds, the instantaneous spike rate rather than the time-averaged neural activity is the appropriate coding principle by comparing both coding parameters in a thoracic interneuron (Omega neuron ON1) of the cricket (Gryllus bimaculatus) auditory system. When stimulated with different temporal sound patterns, the analysis of the instantaneous spike rate demonstrates that the neuron acts as a low-pass filter for syllable patterns. The instantaneous spike rate is low at high syllable rates, but prominent peaks in the instantaneous spike rate are generated as the syllable rate resembles that of the species-specific pattern. The occurrence and repetition rate of these peaks in the neuronal discharge are sufficient to explain temporal filtering in the cricket auditory pathway as they closely match the tuning of phonotactic behavior to different sound patterns. Thus temporal filtering or "pattern recognition" occurs at an early stage in the auditory pathway.

  2. Estimation of the thermal diffusivity of solids based on instantaneous velocimetry using an interferometer

    Indian Academy of Sciences (India)

    SETTU BALACHANDAR; N C SHIVAPRAKASH; L KAMESWARA RAO

    2017-03-01

    A conceptually new approach is proposed to estimate the thermal diffusivity of optically transparent solids at ambient temperature based on the ‘position-dependent instantaneous velocity’ of isothermal surfaces using a self-reference interferometer. A new analytical model is proposed using the exact solution to relate the instantaneous velocity of isothermal surfaces with the thermal diffusivity of solids. The experiment involves setting up a one-dimensional non-stationary heat flow inside the solid via step-temperature excitation to launch a spectrum of dissimilar ‘moving isothermal surfaces’ at the origin. Moving isothermal surfaces exhibit macroscale ‘rectilinear translatory motion’; the instantaneous velocity of any isothermal surface at any location in the heat affected region is unique and governed by the thermal diffusivity of the solids. The intensity pattern produced by the self-reference interferometer encodes the moving isothermal surfaces into the corresponding moving intensity points. The instantaneous velocities of the intensity points are measured. For a given thermo-optic coefficient, the corresponding values of the isothermal surfaces are predicted to estimate the thermal diffusivity of the solids using BK7 glass as an example. Another improved method is proposed in which thermal diffusivity is estimated without measuring thermo-optic coefficient and quartz glass is utilized as a specimen. The results obtained using the proposed approaches closely match with the literature value.

  3. Instantaneous nonvertical electronic transitions with shaped femtosecond laser pulses: Is it possible?

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Møller, Klaus Braagaard

    2003-01-01

    In molecular electronic transitions, a vertical transition can be induced by an ultrashort laser pulse. That is, a replica of the initial nuclear state-times the transition dipole moment of the electronic transition-can be created instantaneously (on the time scale of nuclear motion) in the excited...

  4. Sediment suspension in oscillatory flow: measurements of instantaneous concentration at high shear

    DEFF Research Database (Denmark)

    Staub, Carsten; Jonsson, Ivar G; Svendsen, Ib A.

    1996-01-01

    Different syphon type suspended load probes were used together with a specially developed ''carousel'' sampler for measurements of the instantaneous sediment concentration in turbulent oscillatory flow over a sand bed, Shields parameters were well above the ripple/flat bed transition region, resu...

  5. The Quest for Instantaneous Perfection and the Demand for "Push-Button" Administration

    Science.gov (United States)

    Batagiannis, Stella C.

    2009-01-01

    Educational leaders in the United States are faced with a society seeking instantaneous perfection, immediate and perfect solutions. In education, this leads to a demand for push-button administration and an abandonment of trust in educators' judgment. As exemplified by the No Child Left Behind Act (2002), the search for quick fixes results in…

  6. The Quest for Instantaneous Perfection and the Demand for "Push-Button" Administration

    Science.gov (United States)

    Batagiannis, Stella C.

    2009-01-01

    Educational leaders in the United States are faced with a society seeking instantaneous perfection, immediate and perfect solutions. In education, this leads to a demand for push-button administration and an abandonment of trust in educators' judgment. As exemplified by the No Child Left Behind Act (2002), the search for quick fixes results in…

  7. Continuous measurements of instantaneous heart rate and its fluctuations before and after hatching in chickens.

    Science.gov (United States)

    Moriya, K; Pearson, J T; Burggren, W W; Ar, A; Tazawa, H

    2000-03-01

    There has been considerable interest in heart rate (fh) fluctuations in relation to cardiovascular control systems and foetal conditions during pregnancy in mammals. Prominent fluctuations in fh also occur in avian embryos, which are an important experimental model for studying developmental physiology. The present study determined the instantaneous fh of seven chick embryos continuously from the last stage of prenatal development (day 18), throughout the pipping (perinatal) period (days 19-21) until hatching and, subsequently, of newly hatched chicks (up to day 2). The distinctive patterns of instantaneous fh fluctuations took the form of specific changes within a broad mean fh baseline. Cyclic oscillations (ultradian rhythm) occurred until an early stage of the perinatal period, when the fh baseline started rising. Subsequently, the baseline dropped and respiratory arrhythmia began to appear concomitant with external pipping. During the final stage of external pipping, when the fh baseline rose again prior to hatching, three unique patterns of instantaneous fh fluctuations were evident: relatively long-lasting cyclic small accelerations, irregular intermittent large accelerations and short-term repeated large accelerations. Furthermore, repeated alternate occurrences of the latter two types of acceleration formed an additional oscillating pattern with a period of 10-15 min. During the early period after hatching, when the fh baseline reached its maximum, instantaneous fh changed relatively slowly accompanied by transient rapid decelerations, probably due to augmented vagal tone. Subsequently, the mean fh baseline dropped to its minimum, and a circadian rhythm and three types of previously reported fh fluctuations (types I-III) appeared. Developmental patterns of mean fh and the appearance of distinctive patterns of instantaneous fluctuations in fh and circadian rhythms were not influenced by an ultimate failure of hatching after a normal development. The

  8. Experiments of ECCS strainer blockage and debris settling in suppression pools

    Energy Technology Data Exchange (ETDEWEB)

    Hecker, G.E.; Johnson, A.B.; Murthy, P.; Padmanabhan

    1996-03-01

    If a rupture occurs in a nuclear power station pipe that leads to or from the reactor pressure vessel, the resultant Loss of Coolant Accident (LOCA) would initiate a chain of events involving complex flow phenomena. In a Boiling Water Reactor (BWR), the steam or liquid pipe break pressurizes the dry well, forcing the inert containment gases and steam through downcomers into the suppression pool, thoroughly mixing any particulates and pipe insulation debris carried with the gas flow to the pool. As the steam flow decreases, its unsteady condensation at the end of the downcomers (Condensation Oscillation and Chugging) produces continued water motion in the suppression pool and downcomers. During the blowdown event, high pressure and then low pressure pumps automatically start injecting water from the suppression pool into the reactor to keep its temperature under control. Proper functioning of this Emergency Core Cooling System (ECCS) is critical for the first 30 minutes or so, before operators have time to consider and align alternative sources of cooling water. A major concern for proper operation of the ECCS is the effect of fragmented insulation and plant particulates on the head loss at pump suction strainers. Sufficient loss could exceed the NPSH margin, causing cavitation with a resultant loss of pump capacity and longevity. The bead loss increases with the mass of debris accumulated on the pump strainers, which in turn is dependent on the debris concentration versus time in the suppression pool. This paper describes two sets of experiments that quantified the strainer head loss. One set of experiments considered the mixing and settling of fibrous insulation debris and fine iron oxide particles in the suppression pool during and after chugging. These tests used a reduced scale facility which duplicated the kinetic energy per unit water volume to define the concentration of the actual materials in the pool versus time.

  9. Quantifying the risk of extreme aviation accidents

    Science.gov (United States)

    Das, Kumer Pial; Dey, Asim Kumer

    2016-12-01

    Air travel is considered a safe means of transportation. But when aviation accidents do occur they often result in fatalities. Fortunately, the most extreme accidents occur rarely. However, 2014 was the deadliest year in the past decade causing 111 plane crashes, and among them worst four crashes cause 298, 239, 162 and 116 deaths. In this study, we want to assess the risk of the catastrophic aviation accidents by studying historical aviation accidents. Applying a generalized Pareto model we predict the maximum fatalities from an aviation accident in future. The fitted model is compared with some of its competitive models. The uncertainty in the inferences are quantified using simulated aviation accident series, generated by bootstrap resampling and Monte Carlo simulations.

  10. Injuries to pedestrians in road traffic accidents.

    OpenAIRE

    Atkins, R. M.; Turner, W H; Duthie, R. B.; Wilde, B. R.

    1988-01-01

    Although there have been many reports on injuries to occupants of cars in road traffic accidents, there have been few prospective studies of injuries to pedestrians in such accidents. For this reason a two year prospective study of pedestrians in road traffic accidents in the Oxford region was carried out. The incidence of death in pedestrians was significantly higher than in car occupants or motorcyclists. The principal determinant of death was the weight of the vehicle concerned. The most c...

  11. Why Airplanes Crash: Causes of Accidents Worldwide

    OpenAIRE

    Oster, Clinton V.; John S. Strong; Zorn, Kurt

    2010-01-01

    In this paper, we report the results of a detailed examination of the causes of 700 fatal aviation accidents that occurred worldwide between 1990 and 2006 in commercial passenger service. We look at both scheduled and nonscheduled and both domestic and international service. We also categorize the accident aircraft as large jets, regional and medium jets, small jets, turboprops, and piston powered aircraft. We find that the mix of causes of those accidents vary substantially across regions of...

  12. COMMERCIAL SNF ACCIDENT RELEASE FRACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    S.O. Bader

    1999-10-18

    The purpose of this design analysis is to specify and document the total and respirable fractions for radioactive materials that are released from an accident event at the Monitored Geologic Repository (MGR) involving commercial spent nuclear fuel (CSNF) in a dry environment. The total and respirable release fractions will be used to support the preclosure licensing basis for the MGR. The total release fraction is defined as the fraction of total CSNF assembly inventory, typically expressed as an activity inventory (e.g., curies), of a given radionuclide that is released to the environment from a waste form. The radionuclides are released from the inside of breached fuel rods (or pins) and from the detachment of radioactive material (crud) from the outside surfaces of fuel rods and other components of fuel assemblies. The total release fraction accounts for several mechanisms that tend to retain, retard, or diminish the amount of radionuclides that are available for transport to dose receptors or otherwise can be shown to reduce exposure of receptors to radiological releases. The total release fraction includes a fraction of airborne material that is respirable and could result in inhalation doses. This subset of the total release fraction is referred to as the respirable release fraction. Potential accidents may involve waste forms that are characterized as either bare (unconfined) fuel assemblies or confined fuel assemblies. The confined CSNF assemblies at the MGR are contained in shipping casks, canisters, or disposal containers (waste packages). In contrast to the bare fuel assemblies, the container that confines the fuel assemblies has the potential of providing an additional barrier for diminishing the total release fraction should the fuel rod cladding breach during an accident. However, this analysis will not take credit for this additional bamer and will establish only the total release fractions for bare unconfined CSNF assemblies, which may however be

  13. Relationship between childhood hyperactivity and accident proneness.

    Science.gov (United States)

    Gayton, W F; Bailey, C; Wagner, A; Hardesty, V A

    1986-10-01

    Previous research suggested that hyperactive children are especially susceptible to accidents. Two questions remain: is the relationship peculiar to hyperactivity in childhood or for behaviorally disturbed children in general and does the relationship hold for females as well as for males? To answer these questions 189 patients at a child psychiatric clinic were rated on a scale which included measures of hyperactivity and accident proneness. The hyperactive patients were more likely to be described as accident prone than nonhyperactive patients. The relationship between childhood hyperactivity and accident proneness is confirmed and is specific. The relationship holds for both boys and girls.

  14. Systematics of Reconstructed Process Facility Criticality Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Pruvost, N.L.; McLaughlin, T.P.; Monahan, S.P.

    1999-09-19

    The systematics of the characteristics of twenty-one criticality accidents occurring in nuclear processing facilities of the Russian Federation, the United States, and the United Kingdom are examined. By systematics the authors mean the degree of consistency or agreement between the factual parameters reported for the accidents and the experimentally known conditions for criticality. The twenty-one reported process criticality accidents are not sufficiently well described to justify attempting detailed neutronic modeling. However, results of classic hand calculations confirm the credibility of the reported accident conditions.

  15. Methodological guidelines for developing accident modification functions

    DEFF Research Database (Denmark)

    Elvik, Rune

    2015-01-01

    This paper proposes methodological guidelines for developing accident modification functions. An accident modification function is a mathematical function describing systematic variation in the effects of road safety measures. The paper describes ten guidelines. An example is given of how to use...... limitations in developing accident modification functions are the small number of good evaluation studies and the often huge variation in estimates of effect. It is therefore still not possible to develop accident modification functions for very many road safety measures. © 2015 Elsevier Ltd. All rights...

  16. Occupational Accidents with Agricultural Machinery in Austria.

    Science.gov (United States)

    Kogler, Robert; Quendler, Elisabeth; Boxberger, Josef

    2016-01-01

    The number of recognized accidents with fatalities during agricultural and forestry work, despite better technology and coordinated prevention and trainings, is still very high in Austria. The accident scenarios in which people are injured are very different on farms. The common causes of accidents in agriculture and forestry are the loss of control of machine, means of transport or handling equipment, hand-held tool, and object or animal, followed by slipping, stumbling and falling, breakage, bursting, splitting, slipping, fall, and collapse of material agent. In the literature, a number of studies of general (machine- and animal-related accidents) and specific (machine-related accidents) agricultural and forestry accident situations can be found that refer to different databases. From the database Data of the Austrian Workers Compensation Board (AUVA) about occupational accidents with different agricultural machinery over the period 2008-2010 in Austria, main characteristics of the accident, the victim, and the employer as well as variables on causes and circumstances by frequency and contexts of parameters were statistically analyzed by employing the chi-square test and odds ratio. The aim of the study was to determine the information content and quality of the European Statistics on Accidents at Work (ESAW) variables to evaluate safety gaps and risks as well as the accidental man-machine interaction.

  17. Aerospace Accident - Injury Autopsy Data System -

    Data.gov (United States)

    Department of Transportation — The Aerospace Accident Injury Autopsy Database System will provide the Civil Aerospace Medical Institute (CAMI) Aerospace Medical Research Team (AMRT) the ability to...

  18. Accident Management in VVER-1000

    Directory of Open Access Journals (Sweden)

    F. D'Auria

    2008-01-01

    Full Text Available The present paper deals with the investigation study on accident management in VVER-1000 reactor type conducted in the framework of a European Commission funded project. The mentioned study involved both experimental and computational fields. The purpose of this paper is to summarize the main findings from the execution of a wide-range analysis focused on AM in VVER-1000 with main regard to the qualification of computational tools and the proposal for an optimal AM strategy for this kind of NPP.

  19. HTGR severe accident sequence analysis

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, R.M.; Ball, S.J.; Kornegay, F.C.

    1982-01-01

    Thermal-hydraulic, fission product transport, and atmospheric dispersion calculations are presented for hypothetical severe accident release paths at the Fort St. Vrain (FSV) high temperature gas cooled reactor (HTGR). Off-site radiation exposures are calculated for assumed release of 100% of the 24 hour post-shutdown core xenon and krypton inventory and 5.5% of the iodine inventory. The results show conditions under which dose avoidance measures would be desirable and demonstrate the importance of specific release characteristics such as effective release height. 7 tables.

  20. HEART-RATE-VARIABILITY SPECTRA BASED ON NONEQUIDISTANT SAMPLING - THE SPECTRUM OF COUNTS AND THE INSTANTANEOUS HEART-RATE SPECTRUM

    NARCIS (Netherlands)

    VANSTEENIS, HG; TULEN, JHM; MULDER, LJM

    1994-01-01

    This paper compares two methods to estimate heart rate variability spectra i.e., the spectrum of counts and the instantaneous heart rate spectrum. Contrary to Fourier techniques based on equidistant sampling of the interbeat intervals, the spectrum of counts of the instantaneous heart rate spectrum

  1. HEART-RATE-VARIABILITY SPECTRA BASED ON NONEQUIDISTANT SAMPLING - THE SPECTRUM OF COUNTS AND THE INSTANTANEOUS HEART-RATE SPECTRUM

    NARCIS (Netherlands)

    VANSTEENIS, HG; TULEN, JHM; MULDER, LJM

    This paper compares two methods to estimate heart rate variability spectra i.e., the spectrum of counts and the instantaneous heart rate spectrum. Contrary to Fourier techniques based on equidistant sampling of the interbeat intervals, the spectrum of counts of the instantaneous heart rate spectrum

  2. Accident Prediction Models for Akure – Ondo Carriageway, Ondo ...

    African Journals Online (AJOL)

    FIRST LADY

    Accident data on the 52km Akure-Ondo Carriageway and Spot Speed data were collected ... fatal accident and 62% non-fatal accident, However, the regression analysis ... corresponding vehicle kilometre of travel, commerce, and transportation ... of accident can provide insight into the causes that contributed to accident.

  3. Simulation of a channel blockage transient in the Angra 2 Nuclear Reactor using a RELAP5-3D model

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Mantecon, Javier; Costa, Antonella L.; Veloso, Maria Auxiliadora F.; Pereira, Claubia; Reis, Patricia A.L.; Scari, Maria E., E-mail: mantecon1987@gmail.com, E-mail: antonella@nuclear.ufmg.br, E-mail: dora@nuclear.ufmg.br, E-mail: claubia@nuclear.ufmg.br, E-mail: patricialire@yahoo.com.br, E-mail: melizabethscari@yahoo.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Escola de Engenharia. Departamento de Engenharia Nuclear

    2015-07-01

    The Angra 2 Nuclear Power Plant (NPP) is a Pressurized Water Reactor (PWR) type with electrical output of about 1350 MW. The RELAP5-3D code was used to develop a detailed thermal hydraulic model of such reactor using reference data from the Angra 2 Final Safety Analysis Report (FSAR). In this work, a blockage transient has been investigated at full power operation. The transient herein considered is related to total obstruction of a core cooling channel of one fuel assembly. The calculations were performed using a point kinetic model. The reactor behavior after this transient was analyzed and the time evolution of cladding and coolant temperatures mass flow and void fraction are presented. (author)

  4. The effect of a therapeutic dendritic cell-based cancer vaccination depends on the blockage of CTLA-4 signaling

    DEFF Research Database (Denmark)

    Met, Ozcan; Wang, Mingjun; Pedersen, Anders E

    2006-01-01

    Dendritic cells (DCs) were pulsed with the H-2K(b) binding OVA(257-264)-peptide (SIINFEKL), and used as one single-injection vaccine in combination with anti-CTLA-4 monoclonal antibody (mAb) to treat mice inoculated 3 days previously with 3x10(5) E.G7-OVA lymphoma cells. Neither DC vaccination nor...... CTLA-4 blockage alone prevented tumor growth in tumor challenged mice. In contrast, the combination of one vaccination and injection of anti-CTLA-4 mAb lead to rejection or retarded tumor growth in more than 60% of the mice. The OVA-transgene or the SIINFEKL-epitope was not lost in the progressing...

  5. [Multiple injuries in mass accidents].

    Science.gov (United States)

    Wondrák, E

    1984-01-01

    The treatment starts with reanimation, managing the shock, followed by life-saving surgery on the central nervous system, chest, abdomen, large blood vessels and the uropoietic system. From the very beginning the therapy should be conducted on an intradisciplinary basis, first with the anaesthesiologist, later with other specialists as required. Once the patient's life has been saved, treatment of eyes, hands and systematic attention to extremities should follow. Shock has to be managed within 24 hours. Luxations of large joints should be reposed on the date of injury, open fractures closed, all fractures immobilized in favourable position. No extension should be applied in patients suffering from brain injuries; fractures of the femur should be fixed surgically by a second team in the course of the neurosurgical operation. A stomatologist's assistance makes general anaesthesia possible even with fractures of the jaw. In mass accidents the therapeutic plan for the polytraumatized should be fixed on the following day. A mass accident involving 35 injured treated within two and a half hours demonstrates this procedure in 7 polytraumatized persons.

  6. 2D Temperature Analysis of Energy and Exergy Characteristics of Laminar Steady Flow across a Square Cylinder under Strong Blockage

    Directory of Open Access Journals (Sweden)

    M. Ozgun Korukcu

    2015-05-01

    Full Text Available Energy and exergy characteristics of a square cylinder (SC in confined flow are investigated computationally by numerically handling the steady-state continuity, Navier-Stokes and energy equations in the Reynolds number range of Re = 10–50, where the blockage ratio (β = B/H is kept constant at the high level of β = 0.8. Computations indicated for the upstream region that, the mean non-dimensional streamwise (u/Uo and spanwise (v/Uo velocities attain the values of u/Uo = 0.840®0.879 and v/Uo = 0.236®0.386 (Re = 10®50 on the front-surface of the SC, implying that Reynolds number and blockage have stronger impact on the spanwise momentum activity. It is determined that flows with high Reynolds number interact with the front-surface of the SC developing thinner thermal boundary layers and greater temperature gradients, which promotes the thermal entropy generation values as well. The strict guidance of the throat, not only resulted in the fully developed flow character, but also imposed additional cooling; such that the analysis pointed out the drop of duct wall (y = 0.025 m non-dimensional temperature values (ζ from ζ = 0.387®0.926 (Re = 10®50 at xth = 0 mm to ζ = 0.002®0.266 at xth = 40 mm. In the downstream region, spanwise thermal disturbances are evaluated to be most inspectable in the vortex driven region, where the temperature values show decrease trends in the spanwise direction. In the corresponding domain, exergy destruction is determined to grow with Reynolds number and decrease in the streamwise direction (xds = 0®10 mm. Besides, asymmetric entropy distributions as well were recorded due to the comprehensive mixing caused by the vortex system.

  7. Measured Instantaneous Viscous Boundary Layer in Turbulent Rayleigh-B\\'{e}nard Convection

    CERN Document Server

    Zhou, Quan

    2009-01-01

    We report measurements of the instantaneous viscous boundary layer (BL) thickness $\\delta_v(t)$ in turbulent Rayleigh-B\\'{e}nard convection. It is found that $\\delta_v(t)$ obtained from the measured instantaneous two-dimensional velocity field exhibits intermittent fluctuations. For small values, $\\delta_v(t)$ obeys a lognormal distribution, whereas for large values the distribution of $\\delta_v(t)$ exhibits an exponential tail. The variation of $\\delta_v(t)$ with time is found to be driven by the fluctuations of the large-scale mean flow velocity, as expected, and the local horizontal velocities close to the plate can be used as an instant measure of this variation. It is further found that the mean velocity profile measured in the laboratory frame can now be brought into coincidence with the theoretical Blasius laminar BL profile, if it is resampled relative to the time-dependent frame of $\\delta_v(t)$.

  8. Gradient for the acoustic VTI full waveform inversion based on the instantaneous traveltime sensitivity kernels

    KAUST Repository

    Djebbi, Ramzi

    2015-08-19

    The instantaneous traveltime is able to reduce the non-linearity of full waveform inversion (FWI) that originates from the wrapping of the phase. However, the adjoint state method in this case requires a total of 5 modeling calculations to compute the gradient. Also, considering the larger modeling cost for anisotropic wavefield extrapolation and the necessity to use a line-search algorithm to estimate a step length that depends on the parameters scale, we propose to calculate the gradient based on the instantaneous traveltime sensitivity kernels. We, specifically, use the sensitivity kernels computed using dynamic ray-tracing to build the gradient. The resulting update is computed using a matrix decomposition and accordingly the computational cost is reduced. We consider a simple example where an anomaly is embedded into a constant background medium and we compute the update for the VTI wave equation parameterized using vh, η and ε.

  9. Instantaneous Power Theory with Fourier and Optimal Predictive Controller Design for Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Suksan Tiyarachakun

    2014-01-01

    Full Text Available This paper presents a novel harmonic identification algorithm of shunt active power filter for balanced and unbalanced three-phase systems based on the instantaneous power theory called instantaneous power theory with Fourier. Moreover, the optimal design of predictive current controller using an artificial intelligence technique called adaptive Tabu search is also proposed in the paper. These enhancements of the identification and current control parts are the aim of the good performance for shunt active power filter. The good results for harmonic mitigation using the proposed ideas in the paper are confirmed by the intensive simulation using SPS in SIMULINK. The simulation results show that the enhanced shunt active power filter can provide the minimum %THD (Total Harmonic Distortion of source currents and unity power factor after compensation. In addition, the %THD also follows the IEEE Std.519-1992.

  10. Comparison of Signals from Gravitational Wave Detectors with Instantaneous Time-Frequency Maps

    CERN Document Server

    Stroeer, Alexander; Camp, Jordan

    2011-01-01

    Gravitational wave astronomy relies on the use of multiple detectors, so that coincident detections may distinguish real signals from instrumental artifacts, and also so that relative timing of signals can provide the sky position of sources. We show that the comparison of instantaneous time-frequency and time- amplitude maps provided by the Hilbert-Huang Transform (HHT) can be used effectively for relative signal timing of common signals, to discriminate between the case of identical coincident signals and random noise coincidences, and to provide a classification of signals based on their time-frequency trajectories. The comparison is done with a chi-square goodness-of-fit method which includes contributions from both the instantaneous amplitude and frequency components of the HHT to match two signals in the time domain. This approach naturally allows the analysis of waveforms with strong frequency modulation.

  11. The third post-Newtonian gravitational waveforms for compact binary systems in general orbits: instantaneous terms

    CERN Document Server

    Mishra, Chandra Kant; Iyer, Bala R

    2015-01-01

    We compute the instantaneous contributions to the spherical harmonic modes of gravitational waveforms from compact binary systems in general orbits up to the third post-Newtonian order. We further extend these results for compact binaries in quasi-elliptical orbits using the 3PN quasi-Keplerian representation of the conserved dynamics of compact binaries in eccentric orbits. Using the multipolar post-Minkowskian formalism, starting from the different mass and current type multipole moments, we compute the spin weighted spherical harmonic decomposition of the instantaneous part of the gravitational waveform. These are terms which are functions of the retarded time and do not depend on the history of the binary evolution. Together with the hereditary part, which depends on the binary's dynamical history, these waveforms form the basis for construction of accurate templates for the detection of gravitational wave signals from binaries moving in quasi-elliptical orbits.

  12. Instantaneous Kinematics Analysis via Screw-theory of a Novel 3-CRC Parallel Mechanism

    Directory of Open Access Journals (Sweden)

    Hussein de la Torre

    2016-06-01

    Full Text Available This paper presents the mobility and kinematics analysis of a novel parallel mechanism that is composed by one base, one platform and three identical limbs with CRC joints. The paper obtains closed-form solutions to the direct and inverse kinematics problems, and determines the mobility of the mechanism and instantaneous kinematics by applying screw theory. The obtained results show that this parallel robot is part of the family 2R1T, since the platform shows 3 DOF, i.e.: one translation perpendicular to the base and two rotations about skew axes. In order to calculate the direct instantaneous kinematics, this paper introduces the vector mh, which is part of the joint velocity vector that multiplies the overall inverse Jacobian matrix. This paper compares the results between simulations and numerical examples using Mathematica and SolidWorks in order to prove the accuracy of the analytical results.

  13. Dynamic hydrologic modeling using the zero-parameter Budyko model with instantaneous dryness index

    Science.gov (United States)

    Biswal, Basudev

    2016-09-01

    Long-term partitioning of hydrologic quantities is achieved by using the zero-parameter Budyko model which defines a dryness index. However, this approach is not suitable for dynamic partitioning particularly at diminishing timescales, and therefore, a universally applicable zero-parameter model remains elusive. Here an instantaneous dryness index is proposed which enables dynamic hydrologic modeling using the Budyko model. By introducing a "decay function" that characterizes the effects of antecedent rainfall and solar energy on the dryness state of a basin at a time, I propose the concept of instantaneous dryness index and use the Budyko function to perform continuous hydrologic partitioning. Using the same decay function, I then obtain discharge time series from the effective rainfall time series. The model is evaluated by considering data form 63 U.S. Geological Survey basins. Results indicate the possibility of using the proposed framework as an alternative platform for prediction in ungagued basins.

  14. Analysis of Signals with Fast-Varying Instantaneous Frequency: Window Selection and Insights from Synchrosqueezing Transform

    CERN Document Server

    Sheu, Yae-lin; Wu, Hau-tieng

    2015-01-01

    We develop a theory for analyzing a signal that consists of multiple oscillatory components with fast-varying instantaneous frequencies. In order to describe this kind of signals, the adaptive harmonic model is extended to include fast-varying instantaneous frequency components. Moreover, we apply the Renyi entropy to measure the time-frequency representation provided by synchrosqueezing transform and determine an optimal window width. For a signal with multiple components, which induce coupling artifacts, we propose an adaptive optimal window approach by segmenting the signal into several sections. Examples presented include a synthetic signal and an application to attosecond physics considering the atomic time-varying dipole moment driven by a two-color midinfrared laser fields.

  15. Instantaneous strain measurements during high-temperature stress cycling of a dispersion-strengthened niobium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, D.M.; Mishra, R.S.; Mukherjee, A.K. [Univ. of California, Davis, CA (United States). Dept. of Chemical Engineering and Materials Science

    1995-06-01

    Experimental results obtained from stress cycling tests performed during high-temperature creep of a dispersion strengthened niobium alloy indicate that the instantaneous strain following the stress change decreases with accumulated strain. The true work-hardening rate was shown to be a small fraction of the elastic modulus which remained fairly constant throughout the strain history. The instantaneous strain change from a stress addition was typically greater than the strain from the corresponding stress reduction. This effect is quite pronounced for small stress changes and diminishes as the magnitude of the stress change increases. This implies that the mobility of dislocations is impeded in the reverse direction unless the magnitude of stress reduction exceeds the value of the internal stress.

  16. Experimental evaluation of instantaneous phase based index for structural health monitoring

    Science.gov (United States)

    Jha, Ratneshwar; Cross, Kevin; Janoyan, Kerop D.; Sazonov, Edward S.; Fuchs, Michael; Krishnamurthy, Vidya

    2006-03-01

    The sensitivity and consistency of a damage index based on instantaneous phase values obtained through vibration measurements of a structure is investigated experimentally. An 'empirical mode decomposition' is performed to decompose structural vibrations into a small number of 'intrinsic mode functions' following the methodology generally known as the Hilbert-Huang Transform. Instantaneous phase information is derived through the Hilbert transform of intrinsic mode functions. The damage index is based on the idea that the difference in phase functions between any two points on a structure is altered if the structure is damaged. Experimental investigations are performed on a beam structure with varying excitations (white noise signals), damage levels, and damage locations. The damage index shows generally consistent results, but its sensitivity to damages needs improvements for practical applications.

  17. DC uninterrupted power supply having instantaneous switching followed by low impedance switching

    Science.gov (United States)

    Hammond, Russell E.; Northup, Robert L.; Shimp, Alan G.

    1991-10-01

    An uninterruptible power supply is provided that incorporates switching circuitry permitting a path for instantaneous DC backup power to be supplied to a voltage-declining primary power supply bus. Once the instantaneous transition is made, battery power is switched to a low impedance path to provide long-term battery power delivery to the bus. At a point where the backup batteries no longer supply useful power to a load, disabling circuitry disconnects the batteries from the load so that excessive draining of the batteries does not result in irreversible battery damage. The uninterruptible power supply of the invention further includes an automatic battery charging circuitry that seeks to maintain the power supply batteries at optimal charge level. To enable an operator to adequately assess battery charge condition, the invention provides battery test circuitry that causes a simulated load to appear at the power supply batteries. Visual representations are then made as to battery status.

  18. Instantaneous spectrum estimation of earthquake ground motions based on unscented Kalman filter method

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Representing earthquake ground motion as time varying ARMA model, the instantaneous spectrum can only be determined by the time varying coefficients of the corresponding ARMA model. In this paper, unscented Kalman filter is applied to estimate the time varying coefficients. The comparison between the estimation results of unscented Kalman filter and Kalman filter methods shows that unscented Kalman filter can more precisely represent the distribution of the spectral peaks in time-frequency plane than Kalman filter, and its time and frequency resolution is finer which ensures its better ability to track the local properties of earthquake ground motions and to identify the systems with nonlinearity or abruptness. Moreover, the estimation results of ARMA models with different orders indicate that the theoretical frequency resolving power ofARMA model which was usually ignored in former studies has great effect on the estimation precision of instantaneous spectrum and it should be taken as one of the key factors in order selection of ARMA model.

  19. Seeding optimization for instantaneous volumetric velocimetry. Application to a jet in crossflow

    CERN Document Server

    Cambonie, Tristan

    2014-01-01

    Every volumetric velocimetry measurements based on tracer (particles, bubbles, etc.) detection can be strongly influenced by the optical screening phenomenon. It has to be taken into account when the the statistical properties associated to the performances of the particle detection and tracking algorithms are significantly affected. It leads to a maximum concentration of particles in the images thus limiting the final spatial resolution of the instantaneous three-dimensional three-components (3D3C) velocity fields. A volumetric velocimetry system based on Defocused Digital Particle Image Velocimetry is used to show that above a critical visual concentration of particles in the images, the concentration and accuracy of the final instantaneous raw velocity vector field drop. The critical concentration depends on physical parameters as well as on the processing algorithms. Three distinct regimes are identified. In the first regime, the concentration is well adapted to volumetric velocimetry, the largest concent...

  20. Instantaneous Kinematics Analysis via Screw-Theory of a Novel 3-CRC Parallel Mechanism

    Directory of Open Access Journals (Sweden)

    Hussein de la Torre

    2016-06-01

    Full Text Available This paper presents the mobility and kinematics analysis of a novel parallel mechanism that is composed by one base, one platform and three identical limbs with CRC joints. The paper obtains closed-form solutions to the direct and inverse kinematics problems, and determines the mobility of the mechanism and instantaneous kinematics by applying screw theory. The obtained results show that this parallel robot is part of the family 2R1T, since the platform shows 3 DOF, i.e.: one translation perpendicular to the base and two rotations about skew axes. In order to calculate the direct instantaneous kinematics, this paper introduces the vector mh, which is part of the joint velocity vector that multiplies the overall inverse Jacobian matrix. This paper compares the results between simulations and numerical examples using Mathematica and SolidWorks in order to prove the accuracy of the analytical results.

  1. Design and Development of ZigBee Based Instantaneous Flat-plate Collector Efficiency Measurement System

    Science.gov (United States)

    Vairamani, K.; Venkatesh, K. Arun; Mathivanan, N.

    2011-01-01

    Computing the efficiency of flat-plate collector is vital in solar thermal system testing. This paper presents the design of ZigBee enabled data acquisition system for instantaneous flat-plate collector efficiency calculation. It involves measurement of parameters like inlet and outlet fluid temperatures, ambient temperature and solar radiation intensity. The designed system has a base station and a sensor node. ZigBee wireless communication protocol is used for communication between the base station and the sensor node for wireless data acquisition. The wireless sensor node which is mounted over the collector plate includes the necessary sensors and associated signal-conditioners. An application program has been developed on LabVIEW platform for data acquisition, processing and analysis and is executed in base station PC. Instantaneous flat-plate collector efficiency is computed and reported.

  2. Radiological accidents balance in medicine; Bilan des accidents radiologiques en medecine

    Energy Technology Data Exchange (ETDEWEB)

    Nenot, J.C.

    1995-12-31

    This work deals with the radiological accidents in medicine. In medicine, the radiation accidents on medical personnel and patients can be the result of over dosage and bad focusing of radiotherapy sealed sources. Sometimes, the accidents, if they are unknown during a time enough for the source to be spread and to expose a lot of persons (in the case of source dismantling for instance) can take considerable dimensions. Others accidents can come from bad handling of linear accelerators and from radionuclide kinetics in some therapies. Some examples of accidents are given. (O.L.). 11 refs.

  3. Key Characteristics of Combined Accident including TLOFW accident for PSA Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bo Gyung; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of); Yoon, Ho Joon [Khalifa University of Science, Technology and Research, Abu Dhabi (United Arab Emirates)

    2015-05-15

    The conventional PSA techniques cannot adequately evaluate all events. The conventional PSA models usually focus on single internal events such as DBAs, the external hazards such as fire, seismic. However, the Fukushima accident of Japan in 2011 reveals that very rare event is necessary to be considered in the PSA model to prevent the radioactive release to environment caused by poor treatment based on lack of the information, and to improve the emergency operation procedure. Especially, the results from PSA can be used to decision making for regulators. Moreover, designers can consider the weakness of plant safety based on the quantified results and understand accident sequence based on human actions and system availability. This study is for PSA modeling of combined accidents including total loss of feedwater (TLOFW) accident. The TLOFW accident is a representative accident involving the failure of cooling through secondary side. If the amount of heat transfer is not enough due to the failure of secondary side, the heat will be accumulated to the primary side by continuous core decay heat. Transients with loss of feedwater include total loss of feedwater accident, loss of condenser vacuum accident, and closure of all MSIVs. When residual heat removal by the secondary side is terminated, the safety injection into the RCS with direct primary depressurization would provide alternative heat removal. This operation is called feed and bleed (F and B) operation. Combined accidents including TLOFW accident are very rare event and partially considered in conventional PSA model. Since the necessity of F and B operation is related to plant conditions, the PSA modeling for combined accidents including TLOFW accident is necessary to identify the design and operational vulnerabilities.The PSA is significant to assess the risk of NPPs, and to identify the design and operational vulnerabilities. Even though the combined accident is very rare event, the consequence of combined

  4. Effect of Morphology of Instantaneous Inoculant on Inoculated Result of Melted Iron

    Institute of Scientific and Technical Information of China (English)

    SHENG Da

    2003-01-01

    The characteristics of some elements in inoculant were analyzed. The effect of the morphology of instantaneous inoculant on its melting velocity was studied. When the inoculants pass through the same sieve number, the volume and the ratio of surface area to volume are different. It is evident from the theoretical analysis and experiment under some conditions that the melting velocity of inoculant depends on the morphology of inoculant. The morphology of inoculant during production should be controlled carefully.

  5. Post-processing methods of PIV instantaneous flow fields for unsteady flows in turbomachines

    OpenAIRE

    Cavazzini, G.; A. Dazin; Pavesi, G; Dupont, P; G. Bois

    2012-01-01

    The Particle Image Velocimetry is undoubtedly one of the most important technique in Fluid-dynamics since it allows to obtain a direct and instantaneous visualization of the flow field in a non-intrusive way. This innovative technique spreads in a wide number of research fields, from aerodynamics to medicine, from biology to turbulence researches, from aerodynamics to combustion processes. The book is aimed at presenting the PIV technique and its wide range of possible applications so as to p...

  6. A minimum-error, energy-constrained neural code is an instantaneous-rate code.

    Science.gov (United States)

    Johnson, Erik C; Jones, Douglas L; Ratnam, Rama

    2016-04-01

    Sensory neurons code information about stimuli in their sequence of action potentials (spikes). Intuitively, the spikes should represent stimuli with high fidelity. However, generating and propagating spikes is a metabolically expensive process. It is therefore likely that neural codes have been selected to balance energy expenditure against encoding error. Our recently proposed optimal, energy-constrained neural coder (Jones et al. Frontiers in Computational Neuroscience, 9, 61 2015) postulates that neurons time spikes to minimize the trade-off between stimulus reconstruction error and expended energy by adjusting the spike threshold using a simple dynamic threshold. Here, we show that this proposed coding scheme is related to existing coding schemes, such as rate and temporal codes. We derive an instantaneous rate coder and show that the spike-rate depends on the signal and its derivative. In the limit of high spike rates the spike train maximizes fidelity given an energy constraint (average spike-rate), and the predicted interspike intervals are identical to those generated by our existing optimal coding neuron. The instantaneous rate coder is shown to closely match the spike-rates recorded from P-type primary afferents in weakly electric fish. In particular, the coder is a predictor of the peristimulus time histogram (PSTH). When tested against in vitro cortical pyramidal neuron recordings, the instantaneous spike-rate approximates DC step inputs, matching both the average spike-rate and the time-to-first-spike (a simple temporal code). Overall, the instantaneous rate coder relates optimal, energy-constrained encoding to the concepts of rate-coding and temporal-coding, suggesting a possible unifying principle of neural encoding of sensory signals.

  7. Instantaneous mechanical fastening of quasi-isotropic CFRP laminates by a self-piercing rivet

    OpenAIRE

    上田, 政人; 三宅, 崇太郎; 長谷川, 寛幸; 平野, 義鎭; Ueda, Masahito; Miyake, Sotaro; Hasegawa, Hiroyuki; Hirano, Yoshiyasu

    2012-01-01

    A modified self-piercing rivet (SPR) has been proposed to mechanically fasten CFRP laminates. The modified SPR consists of a rivet body and two flat washers. The two flat washers were used to suppress delamination in the CFRP laminates at the point of piercing. The advantages of the modified SPR for fastening CFRP laminates are instantaneous process time and low cost. Any pretreatments such as surface treatments or hole drilling are not required. In this study, the viability of the modified S...

  8. The transient response of a quantum wave to an instantaneous potential step switching

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, F [Departamento de Quimica-Fisica, Universidad del Pais Vasco, Apdo 644, 48080 Bilbao (Spain); Cruz, H [Departamento de Fisica Basica, Universidad de La Laguna (Spain); Muga, J G [Departamento de Quimica-Fisica, Universidad del Pais Vasco, Apdo 644, 48080 Bilbao (Spain)

    2002-12-06

    The transient response of a stationary state of a quantum particle in a step potential to an instantaneous change in the step height (a simplified model for a sudden bias switch in an electronic semiconductor device) is solved exactly by means of a semianalytical expression. The characteristic times for the transient process up to the new stationary state are identified. A comparison is made between the exact results and an approximate method.

  9. Estimating the Instantaneous Drag-Wind Relationship for a Horizontally Homogeneous Canopy

    Science.gov (United States)

    Pan, Ying; Chamecki, Marcelo; Nepf, Heidi M.

    2016-07-01

    The mean drag-wind relationship is usually investigated assuming that field data are representative of spatially-averaged metrics of statistically stationary flow within and above a horizontally homogeneous canopy. Even if these conditions are satisfied, large-eddy simulation (LES) data suggest two major issues in the analysis of observational data. Firstly, the streamwise mean pressure gradient is usually neglected in the analysis of data from terrestrial canopies, which compromises the estimates of mean canopy drag and provides misleading information for the dependence of local mean drag coefficients on local velocity scales. Secondly, no standard approach has been proposed to investigate the instantaneous drag-wind relationship, a critical component of canopy representation in LES. Here, a practical approach is proposed to fit the streamwise mean pressure gradient using observed profiles of the mean vertical momentum flux within the canopy. Inclusion of the fitted mean pressure gradient enables reliable estimates of the mean drag-wind relationship. LES data show that a local mean drag coefficient that characterizes the relationship between mean canopy drag and the velocity scale associated with total kinetic energy can be used to identify the dependence of the local instantaneous drag coefficient on instantaneous velocity. Iterative approaches are proposed to fit specific models of velocity-dependent instantaneous drag coefficients that represent the effects of viscous drag and the reconfiguration of flexible canopy elements. LES data are used to verify the assumptions and algorithms employed by these new approaches. The relationship between mean canopy drag and mean velocity, which is needed in models based on the Reynolds-averaged Navier-Stokes equations, is parametrized to account for both the dependence on velocity and the contribution from velocity variances. Finally, velocity-dependent drag coefficients lead to significant variations of the calculated

  10. Holographically emulating sequential versus instantaneous disappearance of vector mesons in a hot environment

    Science.gov (United States)

    Zöllner, R.; Kämpfer, B.

    2016-10-01

    Minor extensions of the soft-wall model are used to accommodate two variants of Regge trajectories of vector meson excitations. At nonzero temperatures, various options for either sequential or instantaneous disappearance of vector mesons as normalizable modes are found, thus emulating deconfinement at a certain temperature in the order of the (pseudo)critical temperature of QCD. The crucial role of the blackness function, which steers the thermodynamic properties of the considered system, is highlighted.

  11. Holographically emulating sequential versus instantaneous disappearance of vector mesons in a hot environment

    CERN Document Server

    Zöllner, Rico

    2016-01-01

    Descent extensions of the soft-wall model are used to accommodate two variants of Regge trajectories of vector meson excitations. At non-zero temperatures, various options for either sequential or instantaneous disappearance of vector mesons as normalisable modes are found, thus emulating deconfinement at a certain temperature in the order of the (pseudo-) critical temperature of QCD. The crucial role of the blackness function, which steers the thermodynamic properties of the considered system, is highlighted.

  12. Estimative of core damage frequency in IPEN IEA-R1 research reactor due to the initiating events of loss of flow caused by channel blockage and loss of coolant caused by a large rupture in the pipe of the primary circuit - PSA level 1

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Daniel Massami [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil); Sabundjian, Gaiane, E-mail: gdjian@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil)

    2011-07-01

    This work applies the methodology of Probabilistic Safety Assessment Level 1 to the research reactor IEA-R1 IPEN-CNEN/SP. Two categories of identified initiating events of accidents in the reactor are studied: loss of flow and loss of primary coolant. Among the initiating events, blockage of flow channel and loss of cooling fluid caused by large pipe rupture in the primary circuit are chosen for a detailed analysis. The event tree technique is used to analyze the evolution of the accident, including the actuation or the fail of actuation of the safety systems and the reactor damages. Using the fault tree the reliability of the following reactor safety systems is evaluated: reactor shutdown system, isolation of the reactor pool, Emergency Core Cooling System (ECCS) and the electric system. Estimative for the frequency of damage to the reactor core and the probability of failure of the analyzed systems are calculated. The estimated values for the frequencies of core damage are within the expected margins and are of the same order of magnitude as those found for similar reactors. The reliability of the reactor shutdown system, isolation of the reactor pool and ECCS are satisfactory for the conditions in which these systems are required. However, for the electric system it is suggested an upgrade to increase its reliability. (author)

  13. A Serious Game for Traffic Accident Investigators

    Science.gov (United States)

    Binsubaih, Ahmed; Maddock, Steve; Romano, Daniela

    2006-01-01

    In Dubai, traffic accidents kill one person every 37 hours and injure one person every 3 hours. Novice traffic accident investigators in the Dubai police force are expected to "learn by doing" in this intense environment. Currently, they use no alternative to the real world in order to practice. This paper argues for the use of an…

  14. Occupational blood exposure accidents in the Netherlands.

    NARCIS (Netherlands)

    Wijk, P.T.L. van; Schneeberger, P.M.; Heimeriks, K.; Boland, G.J.; Karagiannis, I.; Geraedts, J.; Ruijs, W.L.M.

    2010-01-01

    BACKGROUND: To make proper evaluation of prevention policies possible, data on the incidence and associated medical costs of occupational blood exposure accidents in the Netherlands are needed. METHODS: Descriptive analysis of blood exposure accidents and risk estimates for occupational groups. Cost

  15. Fatal traffic accidents and forensic medicine

    Directory of Open Access Journals (Sweden)

    Kazuhiko Kibayashi

    2014-07-01

    Full Text Available In the event of a traffic accident fatality, the death is reported as an “unusual death,” an inquest is conducted, and, if necessary, a forensic autopsy is performed to prove any causal relationship between the accident and the death, identify the vehicle at fault, and determine the cause of the accident. A forensic autopsy of a traffic accident fatality needs to both determine the cause of death and identify the mechanism of injury, an analytical task that requires observation of three major traffic accident factors: the body, the vehicles involved, and the scene of the accident. Also crucial to determining the cause of death is the process of looking into whether the people involved in the accident had any diseases that might affect their driving performance or were under the influence of alcohol or drugs. In order to reduce the number of people killed in traffic accidents, it will be important to promote joint research uniting forensic medicine, clinical medicine, automotive engineering, and road engineering, take measures to limit the impact of inebriated pedestrians and pedestrians suffering from dementia, and ensure proper screening of alcohol and illegal drug consumption in drivers.

  16. Accidents of bus drivers : an epidemiological approach

    NARCIS (Netherlands)

    M.L.I. Pokorny (Mirko); D.H.J. Blom (Dick)

    1985-01-01

    textabstractIn the history of accident research much emphasis has been laid on general statistics, different types of case studies concentrating on various personal factor-s, circumstantial influences etc. Often, in certain waves, the unequal initial liability theory (the accident proneness concept;

  17. Squeal Those Tires! Automobile-Accident Reconstruction.

    Science.gov (United States)

    Caples, Linda Griffin

    1992-01-01

    Methods use to reconstruct traffic accidents provide settings for real life applications for students in precalculus, mathematical analysis, or trigonometry. Described is the investigation of an accident in conjunction with the local Highway Patrol Academy integrating physics, vector, and trigonometry. Class findings were compared with those of…

  18. 48 CFR 36.513 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Accident prevention. 36.513 Section 36.513 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL... prevention. (a) The contracting officer shall insert the clause at 52.236-13, Accident Prevention,...

  19. Chapter 6: Accidents; Capitulo 6: Acidentes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-06-01

    The chapter 6 talks about the accidents with radiators all over the world, specifically, the Stimos, in Italy, 1975, San Salvador, in El Salvador, 1989, Soreq, in Israel, 1990, Nesvizh, in Byelorussian, 1991, in Illinois, US, 1965, in Maryland, US, 1991, Hanoi, Vietnam, 1992, Fleurus, in Belgium, 2006. Comments on the accidents and mainly the learned lessons.

  20. 22 CFR 102.8 - Reporting accidents.

    Science.gov (United States)

    2010-04-01

    ... Foreign Relations DEPARTMENT OF STATE ECONOMIC AND OTHER FUNCTIONS CIVIL AVIATION United States Aircraft Accidents Abroad § 102.8 Reporting accidents. (a) To airline and Civil Aeronautics Administration representatives. If a scheduled United States air carrier is involved the airline representatives concerned will...

  1. An introduction to serious nuclear accident chemistry

    OpenAIRE

    Mark Russell St. John Foreman

    2015-01-01

    A review of the chemistry occurring inside a nuclear power plant during a serious reactor accident is presented. This includes some aspects of the behavior of nuclear fuel, its cladding, cesium and iodine. This review concentrates on the chemistry of an accident in a water-cooled reactor loaded with uranium dioxide or mixed metal oxide fuel.

  2. Global estimates of fatal occupational accidents.

    Science.gov (United States)

    Takala, J

    1999-09-01

    Data on occupational accidents are not available from all countries in the world. Furthermore, underreporting, limited coverage by reporting and compensation schemes, and non-harmonized accident recording and notification systems undermine efforts to obtain worldwide information on occupational accidents. This paper presents a method and new estimated global figures of fatal accidents at work by region. The fatal occupational accident rates reported to the International Labour Office are extended to the total employed workforce in countries and regions. For areas not covered by the reported information, rates from other countries that have similar or comparable conditions are applied. In 1994, an average estimated fatal occupational accident rate in the whole world was 14.0 per 100,000 workers, and the total estimated number of fatal occupational accidents was 335,000. The rates are different for individual countries and regions and for separate branches of economic activity. In conclusion, fatal occupational accident figures are higher than previously estimated. The new estimates can be gradually improved by obtaining and adding data from countries where information is not yet available. Sectoral estimates for at least key economic branches in individual countries would further increase the accuracy.

  3. Mean-field theory for car accidents

    Science.gov (United States)

    Huang, Ding-Wei; Tseng, Wei-Chung

    2001-11-01

    We study analytically the occurrence of car accidents in the Nagel-Schreckenberg traffic model. We obtain exact results for the occurrence of car accidents Pac as a function of the car density ρ and the degree of stochastic braking p1 in the case of speed limit vmax=1. Various quantities are calculated analytically. The nontrivial limit p1-->0 is discussed.

  4. Instantaneous ballistic velocity of suspended Brownian nanocrystals measured by upconversion nanothermometry

    Science.gov (United States)

    Brites, Carlos D. S.; Xie, Xiaoji; Debasu, Mengistie L.; Qin, Xian; Chen, Runfeng; Huang, Wei; Rocha, João; Liu, Xiaogang; Carlos, Luís D.

    2016-10-01

    Brownian motion is one of the most fascinating phenomena in nature. Its conceptual implications have a profound impact in almost every field of science and even economics, from dissipative processes in thermodynamic systems, gene therapy in biomedical research, artificial motors and galaxy formation to the behaviour of stock prices. However, despite extensive experimental investigations, the basic microscopic knowledge of prototypical systems such as colloidal particles in a fluid is still far from being complete. This is particularly the case for the measurement of the particles' instantaneous velocities, elusive due to the rapid random movements on extremely short timescales. Here, we report the measurement of the instantaneous ballistic velocity of Brownian nanocrystals suspended in both aqueous and organic solvents. To achieve this, we develop a technique based on upconversion nanothermometry. We find that the population of excited electronic states in NaYF4:Yb/Er nanocrystals at thermal equilibrium can be used for temperature mapping of the nanofluid with great thermal sensitivity (1.15% K-1 at 296 K) and a high spatial resolution (<1 μm). A distinct correlation between the heat flux in the nanofluid and the temporal evolution of Er3+ emission allows us to measure the instantaneous velocity of nanocrystals with different sizes and shapes.

  5. PIV EXPERIMENTAL RESEARCH OF INSTANTANEOUS FLOW CHARACTERISTICS OF CIRCULAR ORIFICE SYNTHETIC JET

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The instantaneous flow characteristics of circular orifice synthetic jet was experimentally studied by a phase-locked Particle Image Velocimetry (PIV) system. The instantaneous flowfields, including the forming, developing and breaking down of the vortex for the jet were clearly shown by the PIV experimental results. As the basis of the study of the instantaneous flow, 36 images were taken and phase-averaged for each condition. The PIV experiment was mainly focused on the time evolution of the vortex pairs formed in the push cycle, the saddle point existing in the suck cycle, the variation of the centerline velocity in the whole cycle and the cross-stream velocity profiles and their self-similarity. Finally, the orifice depth was changed from 1.5 mm to 2 mm and 3.5 mm in order to study the effect of different orifice depths on the flow structure, which shows that at all stream wise sections, the peak of the mass flux and momentum flux increases as the orifice depth increases. Furthermore, the nondimensional distance of the mass flux from the exit is the maximum, while the nondimensional distance of the centerline velocity peak from the exit is the minimum, and nondimensional distance of the momentum flux from the exit section is between them.

  6. Automatic classification of infant sleep based on instantaneous frequencies in a single-channel EEG signal.

    Science.gov (United States)

    Čić, Maja; Šoda, Joško; Bonković, Mirjana

    2013-12-01

    This study presents a novel approach for the electroencephalogram (EEG) signal quantification in which the empirical mode decomposition method, a time-frequency method designated for nonlinear and non-stationary signals, decomposes the EEG signal into intrinsic mode functions (IMF) with corresponding frequency ranges that characterize the appropriate oscillatory modes embedded in the brain neural activity acquired using EEG. To calculate the instantaneous frequency of IMFs, an algorithm was developed using the Generalized Zero Crossing method. From the resulting frequencies, two different novel features were generated: the median instantaneous frequencies and the number of instantaneous frequency changes during a 30s segment for seven IMFs. The sleep stage classification for the daytime sleep of 20 healthy babies was determined using the Support Vector Machine classification algorithm. The results were evaluated using the cross-validation method to achieve an approximately 90% accuracy and with new examinee data to achieve 80% average accuracy of classification. The obtained results were higher than the human experts' agreement and were statistically significant, which positioned the method, based on the proposed features, as an efficient procedure for automatic sleep stage classification. The uniqueness of this study arises from newly proposed features of the time-frequency domain, which bind characteristics of the sleep signals to the oscillation modes of brain activity, reflecting the physical characteristics of sleep, and thus have the potential to highlight the congruency of twin pairs with potential implications for the genetic determination of sleep.

  7. Instantaneous transfer entropy for the study of cardio-respiratory dynamics.

    Science.gov (United States)

    Valenza, Gaetano; Faes, Luca; Citi, Luca; Orini, Michele; Barbieri, Riccardo

    2015-01-01

    Measures of transfer entropy have been proposed to quantify the directional coupling and strength between two complex physiological variables. Particular attention has been given to nonlinear interactions within cardiovascular and respiratory dynamics as influenced by the autonomic nervous system. However, standard transfer entropy estimates have shown major limitations in dealing with issues concerning stochastic system modeling, limited observations in time, and the assumption of stationarity of the considered physiological variables. Moreover, standard estimates are unable to track time-varying changes in nonlinear coupling with high resolution in time. Here, we propose a novel definition of transfer entropy linked to inhomogeneous point-process theory. Heartbeat and respiratory dynamics are characterized through discrete time series, and modeled through probability density functions (PDFs) which characterize and predict the time until the occurrence of the next physiological event as a function of the past history. As the derived measures of entropy are instantaneously defined through continuos PDFs, a novel index (the Instantaneous point-process Transfer Entropy, ipT ransfEn) is able to provide instantaneous tracking of the information transfer. The new measure is tested on experimental data gathered from 16 healthy subjects undergoing postural changes, showing fast tracking of the tilting events and low variability during the standing phase.

  8. Effect of instantaneous and continuous quenches on the density of vibrational modes in model glasses

    Science.gov (United States)

    Lerner, Edan; Bouchbinder, Eran

    2017-08-01

    Computational studies of supercooled liquids often focus on various analyses of their "underlying inherent states"—the glassy configurations at zero temperature obtained by an infinitely fast (instantaneous) quench from equilibrium supercooled states. Similar protocols are also regularly employed in investigations of the unjamming transition at which the rigidity of decompressed soft-sphere packings is lost. Here we investigate the statistics and localization properties of low-frequency vibrational modes of glassy configurations obtained by such instantaneous quenches. We show that the density of vibrational modes grows as ωβ with β depending on the parent temperature T0 from which the glassy configurations were instantaneously quenched. For quenches from high temperature liquid states we find β ≈3 , whereas β appears to approach the previously observed value β =4 as T0 approaches the glass transition temperature. We discuss the consistency of our findings with the theoretical framework of the soft potential model, and contrast them with similar measurements performed on configurations obtained by continuous quenches at finite cooling rates. Our results suggest that any physical quench at rates sufficiently slower than the inverse vibrational time scale—including all physically realistic quenching rates of molecular or atomistic glasses—would result in a glass whose density of vibrational modes is universally characterized by β =4 .

  9. Representation of Instantaneous and Short-term Loudness in the Human Cortex

    Directory of Open Access Journals (Sweden)

    Andrew eThwaites

    2016-04-01

    Full Text Available Acoustic signals pass through numerous transforms in the auditory system before perceptual attributes such as loudness and pitch are derived. However, relatively little is known as to exactly when these transformations happen, and where, cortically or sub-cortically, they occur. In an effort to examine this, we investigated the latencies and locations of cortical entrainment to two transforms predicted by a model of loudness perception for time-varying sounds: the transforms were instantaneous loudness and short-term loudness, where the latter is hypothesized to be derived from the former and therefore should occur later in time. Entrainment of cortical activity was estimated by electro- and magneto-encephalographic (EMEG activity, recorded while healthy subjects listened to continuous speech. There was entrainment to instantaneous loudness bilaterally at 45 ms, 100 ms and 165 ms, in Heschl’s gyrus, dorsal lateral sulcus and Heschl’s gyrus respectively. Entrainment to short-term loudness was found in both the dorsal lateral sulcus and superior temporal sulcus at 275 ms. These results suggest that short-term loudness is derived from instantaneous loudness, and that this derivation occurs after processing in sub-cortical structures.

  10. Recognizing knee pathologies by classifying instantaneous screws of the six degrees-of-freedom knee motion.

    Science.gov (United States)

    Wolf, Alon; Degani, Amir

    2007-05-01

    We address the problem of knee pathology assessment by using screw theory to describe the knee motion and by using the screw representation of the motion as an input to a machine learning classifier. The flexions of knees with different pathologies are tracked using an optical tracking system. The instantaneous screw parameters which describe the transformation of the tibia with respect to the femur in each two successive observation is represented as the instantaneous screw axis of the motion given in its Plücker line coordinates along with its corresponding pitch. The set of instantaneous screw parameters associated with a particular knee with a given pathology is then identified and clustered in R(6) to form a "signature" of the motion for the given pathology. Sawbones model and two cadaver knees with different pathologies were tracked, and the resulting screws were used to train a classifier system. The system was then tested successfully with new, never-trained-before data. The classifier demonstrated a very high success rate in identifying the knee pathology.

  11. Auto-identification of engine fault acoustic signal through inverse trigonometric instantaneous frequency analysis

    Directory of Open Access Journals (Sweden)

    Dayong Ning

    2016-03-01

    Full Text Available The acoustic signals of internal combustion engines contain valuable information about the condition of engines. These signals can be used to detect incipient faults in engines. However, these signals are complex and composed of a faulty component and other noise signals of background. As such, engine conditions’ characteristics are difficult to extract through wavelet transformation and acoustic emission techniques. In this study, an instantaneous frequency analysis method was proposed. A new time–frequency model was constructed using a fixed amplitude and a variable cycle sine function to fit adjacent points gradually from a time domain signal. The instantaneous frequency corresponds to single value at any time. This study also introduced instantaneous frequency calculation on the basis of an inverse trigonometric fitting method at any time. The mean value of all local maximum values was then considered to identify the engine condition automatically. Results revealed that the mean of local maximum values under faulty conditions differs from the normal mean. An experiment case was also conducted to illustrate the availability of the proposed method. Using the proposed time–frequency model, we can identify engine condition and determine abnormal sound produced by faulty engines.

  12. Instantaneous and cumulative influences of competition on impulsive choices in domestic chicks.

    Directory of Open Access Journals (Sweden)

    Hidetoshi eAmita

    2011-09-01

    Full Text Available This study examined instantaneous and cumulative effects of competitive interactions on impulsiveness in the inter-temporal choices in domestic chicks. Chicks were trained to peck colored beads to gain delayed food rewards (1 or 6 grains of millet delivered after a delay ranging between 0–4.5 s, and were tested in binary choices between a small-short delay option (SS and a large-long delay alternative (LL. To examine whether competitive foraging instantaneously changes impulsiveness, we intraindividually compared choices between two consecutive tests in different contexts, one with competitors and another without. We found that (1 the number of the choice of LL was not influenced by competition in the tests, but (2 the operant peck latency was shortened by competition, suggesting a socially enhanced incentive for food. To further examine the lasting changes, two groups of chicks were consecutively trained and tested daily for 2 weeks according to a behavioral titration procedure, one with competitors and another without. Inter-group comparisons of the choices revealed that (3 choice impulsiveness gradually decreased along development, while (4 the chicks trained in competition maintained a higher level of impulsiveness. These results suggest that competitive foraging causes impulsive choices not by direct/contextual modification. Causal link between the instantaneous enhancement of incentive and the gradual effects on impulsivity remains to be examined. Some (yet unspecified factors may be indirectly involved.

  13. Tracking instantaneous entropy in heartbeat dynamics through inhomogeneous point-process nonlinear models.

    Science.gov (United States)

    Valenza, Gaetano; Citi, Luca; Scilingo, Enzo Pasquale; Barbieri, Riccardo

    2014-01-01

    Measures of entropy have been proved as powerful quantifiers of complex nonlinear systems, particularly when applied to stochastic series of heartbeat dynamics. Despite the remarkable achievements obtained through standard definitions of approximate and sample entropy, a time-varying definition of entropy characterizing the physiological dynamics at each moment in time is still missing. To this extent, we propose two novel measures of entropy based on the inho-mogeneous point-process theory. The RR interval series is modeled through probability density functions (pdfs) which characterize and predict the time until the next event occurs as a function of the past history. Laguerre expansions of the Wiener-Volterra autoregressive terms account for the long-term nonlinear information. As the proposed measures of entropy are instantaneously defined through such probability functions, the proposed indices are able to provide instantaneous tracking of autonomic nervous system complexity. Of note, the distance between the time-varying phase-space vectors is calculated through the Kolmogorov-Smirnov distance of two pdfs. Experimental results, obtained from the analysis of RR interval series extracted from ten healthy subjects during stand-up tasks, suggest that the proposed entropy indices provide instantaneous tracking of the heartbeat complexity, also allowing for the definition of complexity variability indices.

  14. Signal Separation and Instantaneous Frequency Estimation Based on Multi-scale Chirplet Sparse Signal Decomposition

    Institute of Scientific and Technical Information of China (English)

    De-jie YU; Jie-si LUO; Mei-li SHI

    2010-01-01

    An approach based an multi-scale chirplet sparse signal de-composition is proposed to separate the multi-component polynomial phase signals, and estimate their instantaneous frequencies. In this paper, we have generated a family of multi-scale chirplet functions which provide good local correlations of chirps over shorter time inter-val. At every decomposition stage, we build the so-called family of chirplets and our idea is to use a structured algorithm which exploits information in the family to chain chirplets together adaptively as to form the polynomial phase signal component whose correlation with the current residue signal is largest. Simultaneously, the polynomial instantaneous frequency is estimated by connecting the linear frequen-cy of the chirplet fixations adopted in the current separation. Simula-tion experiment demonstrated that this method can separate the com-ponents of the multi-component polynomial phase signals effectively even in the low signal-to-noise ratio condition, and estimate its in-stantaneous frequency accurately.

  15. Estimation of instantaneous complex dynamics through Lyapunov exponents: a study on heartbeat dynamics.

    Science.gov (United States)

    Valenza, Gaetano; Citi, Luca; Barbieri, Riccardo

    2014-01-01

    Measures of nonlinearity and complexity, and in particular the study of Lyapunov exponents, have been increasingly used to characterize dynamical properties of a wide range of biological nonlinear systems, including cardiovascular control. In this work, we present a novel methodology able to effectively estimate the Lyapunov spectrum of a series of stochastic events in an instantaneous fashion. The paradigm relies on a novel point-process high-order nonlinear model of the event series dynamics. The long-term information is taken into account by expanding the linear, quadratic, and cubic Wiener-Volterra kernels with the orthonormal Laguerre basis functions. Applications to synthetic data such as the Hénon map and Rössler attractor, as well as two experimental heartbeat interval datasets (i.e., healthy subjects undergoing postural changes and patients with severe cardiac heart failure), focus on estimation and tracking of the Instantaneous Dominant Lyapunov Exponent (IDLE). The novel cardiovascular assessment demonstrates that our method is able to effectively and instantaneously track the nonlinear autonomic control dynamics, allowing for complexity variability estimations.

  16. MARINE ACCIDENTS RESEARCHED THROUGH HUMAN FACTOR PRISMA

    Directory of Open Access Journals (Sweden)

    Branislav M Ćorović

    2013-07-01

    Full Text Available We are aware of a large number of marine accidents that result in numerous casualties and even deaths and substantial negative environmental effects. The objective of this paper is to indicate factors that contribute to human errors which is identified as the most frequent cause to marine accidents. Despite rapid technological development and safety legislation, this paper identifies the human factor as the waekest link in maritime safety system. This analysis could lead to decrease of vessel accidents. In addition, starting from the European Maritime Safety Agency data and by linear regression model application, we have obtained the trend of number of ships involved in marine accidents as well as the trend of lives lost in marine accidents  in and around European Union waters.

  17. [Clinical examinations for the traffic accident patients].

    Science.gov (United States)

    Hitosugi, Masahito

    2008-11-30

    Traffic accident is a leading cause of unintentional death and about six-thousands annually died in Japan. As about one-million of persons suffer from traffic injuries, most of them seek medical attention. Therefore, medical staffs have to find the injuries accurately and treat immediately. Furthermore, the cause of accident should also be considered; why the accident was occurred, human error of the driver? To solve these problems, clinical examinations were needed. Medical staffs have to understand the characteristics of the traffic injuries: severe and multiple blunt injuries, popular injuries can be estimated with considering the pattern of the accident. Because some of the accidents are occurred when the driver is under the influence of alcohol and other drugs, screening of these subjects should be performed. Because the public is largely unaware of the preventable nature of traffic injuries, in addition to diagnose and treat accurately, we medical staffs have to attend on the primary prevention of the traffic injuries.

  18. Review of Severe Accident Phenomena in LWR and Related Severe Accident Analysis Codes

    Directory of Open Access Journals (Sweden)

    Muhammad Hashim

    2013-04-01

    Full Text Available Firstly, importance of severe accident provision is highlighted in view of Fukushima Daiichi accident. Then, extensive review of the past researches on severe accident phenomena in LWR is presented within this study. Various complexes, physicochemical and radiological phenomena take place during various stages of the severe accidents of Light Water Reactor (LWR plants. The review deals with progression of the severe accidents phenomena by dividing into core degradation phenomena in reactor vessel and post core melt phenomena in the containment. The development of various computer codes to analyze these severe accidents phenomena is also summarized in the review. Lastly, the need of international activity is stressed to assemble various severe accidents related knowledge systematically from research organs and compile them on the open knowledge base via the internet to be available worldwide.

  19. Commercial SNF Accident Release Fractions

    Energy Technology Data Exchange (ETDEWEB)

    J. Schulz

    2004-11-05

    The purpose of this analysis is to specify and document the total and respirable fractions for radioactive materials that could be potentially released from an accident at the repository involving commercial spent nuclear fuel (SNF) in a dry environment. The total and respirable release fractions are used to support the preclosure licensing basis for the repository. The total release fraction is defined as the fraction of total commercial SNF assembly inventory, typically expressed as an activity inventory (e.g., curies), of a given radionuclide that is released to the environment from a waste form. Radionuclides are released from the inside of breached fuel rods (or pins) and from the detachment of radioactive material (crud) from the outside surfaces of fuel rods and other components of fuel assemblies. The total release fraction accounts for several mechanisms that tend to retain, retard, or diminish the amount of radionuclides that are available for transport to dose receptors or otherwise can be shown to reduce exposure of receptors to radiological releases. The total release fraction includes a fraction of airborne material that is respirable and could result in inhalation doses; this subset of the total release fraction is referred to as the respirable release fraction. Accidents may involve waste forms characterized as: (1) bare unconfined intact fuel assemblies, (2) confined intact fuel assemblies, or (3) canistered failed commercial SNF. Confined intact commercial SNF assemblies at the repository are contained in shipping casks, canisters, or waste packages. Four categories of failed commercial SNF are identified: (1) mechanically and cladding-penetration damaged commercial SNF, (2) consolidated/reconstituted assemblies, (3) fuel rods, pieces, and debris, and (4) nonfuel components. It is assumed that failed commercial SNF is placed into waste packages with a mesh screen at each end (CRWMS M&O 1999). In contrast to bare unconfined fuel assemblies, the

  20. A Novel Method for Borehole Blockage Removal and Experimental Study on a Hydraulic Self-Propelled Nozzle in Underground Coal Mines

    Directory of Open Access Journals (Sweden)

    Zhaolong Ge

    2016-08-01

    Full Text Available When coal bed methane (CBM drainage boreholes cross fractured, soft, or water-swelling strata, they collapse and block frequently. Borehole blockages result in a rapid decrease in CBM extraction ability, which leads to a reduction in CBM output and threatens coal mine safety production. To solve these problems, a novel method that uses a self-propelled water-jet nozzle to dredge blocked boreholes in coal seams has been proposed on the basis of the existing technology. Based on a theoretical analysis of the reason for borehole caving and the theory of blockage removal, we optimized the nozzle inlet pressure and selected an appropriate high-pressure resin pipe. A field experiment on the blockage removal of blocked CBM drainage boreholes using the proposed method was run in the Fengchun coal mine, Qijiang, Chongqing, southwest China. In this field trial, the time spent to unblock a borehole varied between 18.52 and 34.98 min, which is much shorter than using a drilling rig. After blockage removal, the average pure volume of the methane drainage of a single borehole was increased from 0.03 L/min to ~1.91–7.30 L/min, and the methane drainage concentration of a single borehole increased from 5% to ~44%–85%. The extraction effect increased significantly.

  1. Analysis of Fukushima Daiichi Accident Using HFACS

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, Saeed Almheiri [Korea Advanced Institue of Science and Technology, Daejeon (Korea, Republic of)

    2013-10-15

    The shadow of Fukushima Daiichi nuclear power plant (NPP) accident is still too big and will last long. On the other hand, it could still teach us lots of lessons to better design and operate nuclear power plants. In this paper, we will be focusing on the Fukushima Daiichi accident, especially on human organizational factors. We will analyze the accident using Human Factors Analysis and Classification System (HFACS) in order to better understand the organizational climate of TEPCO{sup 1} and NISA{sup 2} that led to Fukushima Daiichi Accident. HFACS was developed for the U. S. aviation industry and has been used at many industries like the rail and mining industries. We found that the HFACS to be greatly beneficial in investigating the latent and organizational causes for the accident. The application results show that the causes of Fukushima Daiichi accident were spread out from sharp end (i.e. Unsafe Act) to blunt end (i. e. Organizational Influences). This means that the corresponding countermeasures should cover from front line staff to management. Thus, we managed to develop a better understanding on how to prevent similar errors or violations. The incident and near-miss have a lot of helpful information because it may show the actual and latent deficiencies of complex systems. We applied the HFACS into Fukushima Daiichi accident to better locate the causes related to both sharp and blunt ends of operation of NPP. In order to derive useful lessons from the accident analysis, the analyst should try to find the similarities not differences from the incident. It is imperative that whatever accident/incident analysis systems we use, we should fully utilize the disastrous Fukushima accident.

  2. Regulation Plans on Severe Accidents developed by KINS Severe Accident Regulation Preparation TFT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyun Tae; Chung, Ku Young; Na, Han Bee [KINS, Daejeon (Korea, Republic of)

    2016-05-15

    Some nuclear power plants in Fukushima Daiichi site had lost their emergency reactor cooling function for long-time so the fuels inside the reactors were molten, and the integrity of containment was damaged. Therefore, large amount of radioactive material was released to environment. Because the social and economic effects of severe accidents are enormous, Korean Government already issued 'Severe Accident Policy' in 2001 which requires nuclear power plant operators to set up 'Quantitative Safety Goal', to do 'Probabilistic Safety Analysis', to install 'Severe Accident Countermeasures' and to make 'Severe Accident Management Plan'. After the Fukushima disaster, a Special Safety Inspection was performed for all operating nuclear power plants of Korea. The inspection team from industry, academia, and research institutes assessed Korean NPPs capabilities to cope with or respond to severe accidents and emergency situation caused by natural disasters such as a large earthquake or tsunami. As a result of the special inspection, about 50 action items were identified to increase the capability to cope with natural disaster and severe accidents. Nuclear Safety Act has been amended to require NPP operators to submit Accident Management Plant as part of operating license application. The KINS Severe Accident Regulation Preparation TFT had first investigated oversea severe accident regulation trend before and after the Fukushima accident. Then, the TFT has developed regulation draft for severe accidents such as Severe accident Management Plans, the required design features for new NPPs to prevent severe accident against multiple failures and beyond-design external events, countermeasures to mitigate severe accident and to keep the integrity of containment, and assessment methodology on safety assessment plan and probabilistic safety assessment.

  3. Instantaneous death due to transorbital reverse penetration of a screw in an accidental fall: unusual autopsy case report and review of the literature.

    Science.gov (United States)

    Gioia, Sara; Bacci, Mauro; Lancia, Massimo; Carlini, Luigi; Suadoni, Fabio

    2014-03-01

    We present a peculiar autopsy case of a transorbital penetrating head injury, in a male worker, after an accidental fall onto a screw not completely stuck into a wooden board. A 13-cm screw entered the cranium 9.5 cm deep, penetrating with the flat end, a condition defined in literature as "reverse penetration." The death was instantaneous and caused by a neurogenic shock due to injuries to the brain stem and the right cerebellar hemisphere. These injuries, enabled by the length of the screw, are generally described in literature as due to nontransorbital penetrations, frequently associated with posterior entry and a large intracranial injury. The ocular globe has been, furthermore, perfectly preserved thanks to its mobility in the orbit. Even the dynamic of the incident is peculiar because of the stationary nature of the penetrating object, which the victim actively fell on by accident. To the best of our knowledge, the matter is therefore a very peculiar mortal case of transorbital intracranial penetration, whose verified injuries and dynamics are absolutely atypical. The case is now under discussion, and a review of pertinent literature is performed.

  4. Leukemia following the Chernobyl accident.

    Science.gov (United States)

    Howe, Geoffrey R

    2007-11-01

    The accident at the Chernobyl Nuclear Power Plant in Ukraine in 1986 led to a substantial increase of thyroid cancer among those exposed as children. The other cancer that is the most sensitive to the effects of ionizing radiation is leukemia, and this paper evaluates the evidence relating exposure to Chernobyl radioactivity and leukemia risk. Two types of objectives are identified, namely, scientific evidence and public health, and two approaches to addressing such objectives are discussed. Empirical studies in affected populations are summarized, and it is concluded that, possibly apart from Russian cleanup workers, no meaningful evidence of any statistical association between exposure and leukemia risk as yet exists. However, it is important to carry on with such studies to satisfy various public health objectives.

  5. Road accidents and business cycles in Spain.

    Science.gov (United States)

    Rodríguez-López, Jesús; Marrero, Gustavo A; González, Rosa Marina; Leal-Linares, Teresa

    2016-11-01

    This paper explores the causes behind the downturn in road accidents in Spain across the last decade. Possible causes are grouped into three categories: Institutional factors (a Penalty Point System, PPS, dating from 2006), technological factors (active safety and passive safety of vehicles), and macroeconomic factors (the Great recession starting in 2008, and an increase in fuel prices during the spring of 2008). The PPS has been blessed by incumbent authorities as responsible for the decline of road fatalities in Spain. Using cointegration techniques, the GDP growth rate, the fuel price, the PPS, and technological items embedded in motor vehicles appear to be statistically significantly related with accidents. Importantly, PPS is found to be significant in reducing fatal accidents. However, PPS is not significant for non-fatal accidents. In view of these results, we conclude that road accidents in Spain are very sensitive to the business cycle, and that the PPS influenced the severity (fatality) rather than the quantity of accidents in Spain. Importantly, technological items help explain a sizable fraction in accidents downturn, their effects dating back from the end of the nineties.

  6. An analysis of aircraft accidents involving fires

    Science.gov (United States)

    Lucha, G. V.; Robertson, M. A.; Schooley, F. A.

    1975-01-01

    All U. S. Air Carrier accidents between 1963 and 1974 were studied to assess the extent of total personnel and aircraft damage which occurred in accidents and in accidents involving fire. Published accident reports and NTSB investigators' factual backup files were the primary sources of data. Although it was frequently not possible to assess the relative extent of fire-caused damage versus impact damage using the available data, the study established upper and lower bounds for deaths and damage due specifically to fire. In 12 years there were 122 accidents which involved airframe fires. Eighty-seven percent of the fires occurred after impact, and fuel leakage from ruptured tanks or severed lines was the most frequently cited cause. A cost analysis was performed for 300 serious accidents, including 92 serious accidents which involved fire. Personal injury costs were outside the scope of the cost analysis, but data on personnel injury judgements as well as settlements received from the CAB are included for reference.

  7. Accidents in Canada: mortality and hospitalization.

    Science.gov (United States)

    Riley, R; Paddon, P

    1989-01-01

    For Canadians under 45, accidents are the leading cause of both death and hospitalization. For the Canadian population as a whole, accidents rank fourth as a cause of death, after cardiovascular disease (CVD), cancer and respiratory disease. This article analyzes accident mortality and hospitalization in Canada using age-specific rates, age-standardized mortality rates (ASMR), and potential years of life lost (PYLL). The six major causes of accidental death for men are motor vehicle traffic accidents (MVTA), falls, drowning, fires, suffocation and poisoning. For women, the order is slightly different: MVTA, falls, fires, suffocation, poisoning and drowning. From 1971 to 1986, age-standardized mortality rates (ASMR) for accidents decreased by 44% for men and 39% for women. The largest decrease occurred in the under 15 age group. Accidents accounted for 11.5% of total hospital days in 1985, and 8% of hospital discharges. Because young people have the highest rates of accidental death, potential years of life lost (PYLL) are almost as high for accidents as for cardiovascular disease, although CVD deaths outnumbered accidental deaths by almost five to one in 1985.

  8. Professional experience and traffic accidents/near-miss accidents among truck drivers.

    Science.gov (United States)

    Girotto, Edmarlon; Andrade, Selma Maffei de; González, Alberto Durán; Mesas, Arthur Eumann

    2016-10-01

    To investigate the relationship between the time working as a truck driver and the report of involvement in traffic accidents or near-miss accidents. A cross-sectional study was performed with truck drivers transporting products from the Brazilian grain harvest to the Port of Paranaguá, Paraná, Brazil. The drivers were interviewed regarding sociodemographic characteristics, working conditions, behavior in traffic and involvement in accidents or near-miss accidents in the previous 12 months. Subsequently, the participants answered a self-applied questionnaire on substance use. The time of professional experience as drivers was categorized in tertiles. Statistical analyses were performed through the construction of models adjusted by multinomial regression to assess the relationship between the length of experience as a truck driver and the involvement in accidents or near-miss accidents. This study included 665 male drivers with an average age of 42.2 (±11.1) years. Among them, 7.2% and 41.7% of the drivers reported involvement in accidents and near-miss accidents, respectively. In fully adjusted analysis, the 3rd tertile of professional experience (>22years) was shown to be inversely associated with involvement in accidents (odds ratio [OR] 0.29; 95% confidence interval [CI] 0.16-0.52) and near-miss accidents (OR 0.17; 95% CI 0.05-0.53). The 2nd tertile of professional experience (11-22 years) was inversely associated with involvement in accidents (OR 0.63; 95% CI 0.40-0.98). An evident relationship was observed between longer professional experience and a reduction in reporting involvement in accidents and near-miss accidents, regardless of age, substance use, working conditions and behavior in traffic. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Bayes classifiers for imbalanced traffic accidents datasets.

    Science.gov (United States)

    Mujalli, Randa Oqab; López, Griselda; Garach, Laura

    2016-03-01

    Traffic accidents data sets are usually imbalanced, where the number of instances classified under the killed or severe injuries class (minority) is much lower than those classified under the slight injuries class (majority). This, however, supposes a challenging problem for classification algorithms and may cause obtaining a model that well cover the slight injuries instances whereas the killed or severe injuries instances are misclassified frequently. Based on traffic accidents data collected on urban and suburban roads in Jordan for three years (2009-2011); three different data balancing techniques were used: under-sampling which removes some instances of the majority class, oversampling which creates new instances of the minority class and a mix technique that combines both. In addition, different Bayes classifiers were compared for the different imbalanced and balanced data sets: Averaged One-Dependence Estimators, Weightily Average One-Dependence Estimators, and Bayesian networks in order to identify factors that affect the severity of an accident. The results indicated that using the balanced data sets, especially those created using oversampling techniques, with Bayesian networks improved classifying a traffic accident according to its severity and reduced the misclassification of killed and severe injuries instances. On the other hand, the following variables were found to contribute to the occurrence of a killed causality or a severe injury in a traffic accident: number of vehicles involved, accident pattern, number of directions, accident type, lighting, surface condition, and speed limit. This work, to the knowledge of the authors, is the first that aims at analyzing historical data records for traffic accidents occurring in Jordan and the first to apply balancing techniques to analyze injury severity of traffic accidents. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. A Study on the Instantaneous Turbulent Flow Field in a 90-Degree Elbow Pipe with Circular Section

    Directory of Open Access Journals (Sweden)

    Shiming Wang

    2016-01-01

    Full Text Available Based on the special application of 90-degree elbow pipe in the HTR-PM, the large eddy simulation was selected to calculate the instantaneous flow field in the 90-degree elbow pipe combining with the experimental results. The characteristics of the instantaneous turbulent flow field under the influence of flow separation and secondary flow were studied by analyzing the instantaneous pressure information at specific monitoring points and the instantaneous velocity field on the cross section of the elbow. The pattern and the intensity of the Dean vortex and the small scale eddies change over time and induce the asymmetry of the flow field. The turbulent disturbance upstream and the flow separation near the intrados couple with the vortexes of various scales. Energy is transferred from large scale eddies to small scale eddies and dissipated by the viscous stress in the end.

  11. A digital instantaneous frequency measurement technique utilising high speed analogue to digital converters and field programmable gate arrays

    CSIR Research Space (South Africa)

    Herselman, PLR

    2007-09-01

    Full Text Available In modern information and sensor systems, the timely estimation of the carrier frequency of received signals is of critical importance. This paper presents a digital instantaneous frequency measurement (DIFM) technique, which can measure the carrier...

  12. Nonlinear structural joint model updating based on instantaneous characteristics of dynamic responses

    Science.gov (United States)

    Wang, Zuo-Cai; Xin, Yu; Ren, Wei-Xin

    2016-08-01

    This paper proposes a new nonlinear joint model updating method for shear type structures based on the instantaneous characteristics of the decomposed structural dynamic responses. To obtain an accurate representation of a nonlinear system's dynamics, the nonlinear joint model is described as the nonlinear spring element with bilinear stiffness. The instantaneous frequencies and amplitudes of the decomposed mono-component are first extracted by the analytical mode decomposition (AMD) method. Then, an objective function based on the residuals of the instantaneous frequencies and amplitudes between the experimental structure and the nonlinear model is created for the nonlinear joint model updating. The optimal values of the nonlinear joint model parameters are obtained by minimizing the objective function using the simulated annealing global optimization method. To validate the effectiveness of the proposed method, a single-story shear type structure subjected to earthquake and harmonic excitations is simulated as a numerical example. Then, a beam structure with multiple local nonlinear elements subjected to earthquake excitation is also simulated. The nonlinear beam structure is updated based on the global and local model using the proposed method. The results show that the proposed local nonlinear model updating method is more effective for structures with multiple local nonlinear elements. Finally, the proposed method is verified by the shake table test of a real high voltage switch structure. The accuracy of the proposed method is quantified both in numerical and experimental applications using the defined error indices. Both the numerical and experimental results have shown that the proposed method can effectively update the nonlinear joint model.

  13. Reconstruction of temporal variations of evapotranspiration using instantaneous estimates at the time of satellite overpass

    Directory of Open Access Journals (Sweden)

    E. Delogu

    2012-08-01

    Full Text Available Evapotranspiration estimates can be derived from remote sensing data and ancillary, mostly meterorological, information. For this purpose, two types of methods are classically used: the first type estimates a potential evapotranspiration rate from vegetation indices, and adjusts this rate according to water availability derived from either a surface temperature index or a first guess obtained from a rough estimate of the water budget, while the second family of methods relies on the link between the surface temperature and the latent heat flux through the surface energy budget. The latter provides an instantaneous estimate at the time of satellite overpass. In order to compute daily evapotranspiration, one needs an extrapolation algorithm. Since no image is acquired during cloudy conditions, these methods can only be applied during clear sky days. In order to derive seasonal evapotranspiration, one needs an interpolation method. Two combined interpolation/extrapolation methods based on the self preservation of evaporative fraction and the stress factor are compared to reconstruct seasonal evapotranspiration from instantaneous measurements acquired in clear sky conditions. Those measurements are taken from instantaneous latent heat flux from 11 datasets in Southern France and Morocco. Results show that both methods have comparable performances with a clear advantage for the evaporative fraction for datasets with several water stress events. Both interpolation algorithms tend to underestimate evapotranspiration due to the energy limiting conditions that prevail during cloudy days. Taking into account the diurnal variations of the evaporative fraction according to an empirical relationship derived from a previous study improved the performance of the extrapolation algorithm and therefore the retrieval of the seasonal evapotranspiration for all but one datasets.

  14. Instantaneous kinematic phase reflects neuromechanical response to lateral perturbations of running cockroaches.

    Science.gov (United States)

    Revzen, Shai; Burden, Samuel A; Moore, Talia Y; Mongeau, Jean-Michel; Full, Robert J

    2013-04-01

    Instantaneous kinematic phase calculation allows the development of reduced-order oscillator models useful in generating hypotheses of neuromechanical control. When perturbed, changes in instantaneous kinematic phase and frequency of rhythmic movements can provide details of movement and evidence for neural feedback to a system-level neural oscillator with a time resolution not possible with traditional approaches. We elicited an escape response in cockroaches (Blaberus discoidalis) that ran onto a movable cart accelerated laterally with respect to the animals' motion causing a perturbation. The specific impulse imposed on animals (0.50 [Formula: see text] 0.04 m s[Formula: see text]; mean, SD) was nearly twice their forward speed (0.25 [Formula: see text] 0.06 m s[Formula: see text]. Instantaneous residual phase computed from kinematic phase remained constant for 110 ms after the onset of perturbation, but then decreased representing a decrease in stride frequency. Results from direct muscle action potential recordings supported kinematic phase results in showing that recovery begins with self-stabilizing mechanical feedback followed by neural feedback to an abstracted neural oscillator or central pattern generator. Trials fell into two classes of forward velocity changes, while exhibiting statistically indistinguishable frequency changes. Animals pulled away from the side with front and hind legs of the tripod in stance recovered heading within 300 ms, whereas animals that only had a middle leg of the tripod resisting the pull did not recover within this period. Animals with eight or more legs might be more robust to lateral perturbations than hexapods.

  15. a New Model for Describing Evolution and Control of Disaster System Including Instantaneous and Continuous Actions

    Science.gov (United States)

    Chen, Chang-Kun; Li, Zhi; Sun, Yun-Feng

    A new model for describing the disaster system including instantaneous and continuous action synchronously has been developed. The model is composed of three primary parts, that is, the impact from its causative disaster events, stochastic noise of disaster node and self-healing function, and every part is modeled concretely in terms of their characteristics in practice. Some key parameters, namely link appearance probability, retardation coefficient, ultimate repair capacity of government, dynamical modes considering different disaster evolving chains, and the positions of link with the specific performance in disaster network system are involved. Combined with a case study, the proposed model is applied to a certain disaster evolution system, and the influence law of different parameters on disaster evolution process, in disaster networks with instantaneous-action and/or continuous-action, is presented and compared. The results indicate that the destructive impact in the networks by link in continuous action is far greater an order of magnitude than that in instantaneous action. If a link in continuous action emerges in the disaster network system, properties of the causative event for the link, link appearance probability and its position in the network all have a notable influence to the severity of the disaster network. In addition, some peculiar phenomena are also commendably observed in the disaster evolution process based on the model, such as the multipeaks emerging in the destroyed rate number curve for some crisis nodes caused by their various inducing paths together with the relevant retardation coefficients, the existence of the critical value for ultimate repair capacity to recover the disaster node, and so on.

  16. Validation of a Partially Nonlinear Time Domain Model using instantaneous Froude-Krylov and Hydrostatic Forces

    DEFF Research Database (Denmark)

    Guerinel, Matthieu; Zurkinden, Andrew Stephen; Alves, Marco

    2013-01-01

    laboratory of Aalborg University. The device is a prototype of a singleWavestar float, scaled at 1:20, considering one degree of freedom only. The tests included a various range of incoming waves, from small regular waves to storm conditions irregular waves. The numerical simulations have been performed...... the instantaneous detection of the floating body wetted surface. The idea behind this approach is first to increase the model accuracy (compared to the fully linear model method), but also to keep the computational time relatively low. Results show a good agreement between experimental and numerical data, which...

  17. Velocities: mean, average and instantaneous in uniform accelerated motion, some pedagogical comments

    CERN Document Server

    Talero, Paco; Barbosa, Luis H

    2013-01-01

    The relation among instantaneous, mean and average velocities in one-dimensional motion with constant acceleration is studied. It was shown that the instant velocity evaluated in the time $t_{p}=\\left(t_2+t_1\\right)/2$ is similar to the mean and average velocities evaluated between the times $t_1$ and $t_2$. The reason for relations illustrated before were shown in detail. Also, the results obtained were used to propose a pedagogical strategy in order to study the one-dimensional motion with constant acceleration as a natural extension of one-dimensional motion with constant velocity.

  18. Finding the location of the instantaneous center of rotation using a particle image velocimetry algorithm

    Science.gov (United States)

    Claessens, Tom

    2017-03-01

    This work is about planar rigid-body kinematics and, in particular, the principle of the instantaneous center of rotation (IC). Using a computer simulated approach, a workflow is presented that results in a visual representation of the locus of the IC, based on particle image velocimetry (PIV). Here, a small number of digital animations of textured objects are created with multibody dynamics software, and later imported in PIV software to extract the velocity field (magnitude and direction) of objects moving within a plane. We believe the workflow presented may help learners improve their understanding of the concept of the IC, thus enhancing their knowledge of rigid body kinematics.

  19. A Semi-Instantaneous Heat Exchanger for Mobile Solar Collectors Test System

    Directory of Open Access Journals (Sweden)

    Haifeng Cao

    2013-07-01

    Full Text Available A semi-instantaneous heat exchanger which can solve low efficiency and space shortage of mobil test system for thermal performance of solar collectors is proposed in this paper, In this paper, the structure parameters of heat exchanger and the power of heat resistance are designed based on the method of mean temperature difference. The experiment results show the performance of test system has been optimized. The efficiency of collectors test can be increased 50% and the total weight of the primary heater and working medium is reduced to 13.8%.The load of the test vehicle and occupancy volume have been decreased.

  20. The behavior of the instantaneous Poynting vector of symmetrical laser beams

    CSIR Research Space (South Africa)

    Litvin, IA

    2012-06-01

    Full Text Available - ries about 10% of the total oscillation energy, which is inde- pendent of the cone angle. As a result of the presence of the IPV in this region, an appearance of time-averaging fluxes in this region is shown. 2. INSTANTANEOUS POYNTING VECTOR.... (1) and Maxwell?s equations we can easily calcu- late the electric and magnetic field and by the use of the Lorentz gauge for simplification and we arrive at ~B�x; y; z� � ik � U�x; y; z�~j � ik ?U�x; y; z� ?y ~j � ei�kz??t�; (2a) ~E�x; y...

  1. Hysteresis effects in instantaneous frequency scaling of attenuation on 20 and 30 GHz satellite links

    Science.gov (United States)

    Sweeney, D. G.; Pratt, T.; Bostian, C. W.

    1992-01-01

    It has been observed with 20/30 GHz satellite beacon measurements that the ratio of 30 GHz to 20 GHz attenuation changes during some fade events. This ratio displays a hysteresis effect. This effect can be explained by a change in the drop size distribution (DSD) during the event. However, it appears only above approximately 6-8 dB of attenuation at 20 GHz. Instantaneous frequency scaling of attenuation is being proposed as part of an algorithm for uplink power control (ULPC) and the dynamic range of such an algorithm must be appropriately limited to avoid the hysteresis.

  2. Two attosecond pulse transient absorption spectroscopy and extraction of the instantaneous AC Stark shift in helium

    Science.gov (United States)

    Bækhøj, Jens E.; Bojer Madsen, Lars

    2016-07-01

    In two attosecond pulse absorption spectroscopy (TAPAS) the use of two attosecond XUV pulses allows the extraction of atomic and molecular quantum mechanical dipole phases from spectroscopic measurements. TAPAS relies on interference between processes that individually only include a single XUV photon, and therefore does not rely on high intensity attosecond pulses. To show the usefulness and limitations of the TAPAS method we investigate its capability of capturing the instantaneous AC Stark shift induced by a midinfrared 3200 nm pulse in the | 1{{s}}2{{p}}> state of helium.

  3. Instantaneous carbon-carbon bond formation using a microchannel reactor with a catalytic membrane.

    Science.gov (United States)

    Uozumi, Yasuhiro; Yamada, Yoichi M A; Beppu, Tomohiko; Fukuyama, Naoshi; Ueno, Masaharu; Kitamori, Takehiko

    2006-12-20

    Instantaneous catalytic carbon-carbon bond forming reactions were achieved in a microchannel reactor having a polymeric palladium complex membrane. The catalytic membrane was constructed inside the microchannel via self-assembling complexation at the interface between the organic and aqueous phases flowing laminarly, where non-cross-linked polymer-bound phosphine and ammonium tetrachloropalladate dissolved, respectively. A palladium-catalyzed coupling reaction of aryl halides and arylboronic acids was performed using the microchannel reactor to give quantitative yields of biaryls within 4 s of retention time in the defined channel region.

  4. Nanocrystallization kinetics under instantaneous growth approximation: Experiments and cellular automata simulations

    Energy Technology Data Exchange (ETDEWEB)

    Blazquez, J.S.; Millan, M.; Conde, C.F.; Conde, A. [Departamento de Fisica de la Materia Condensada, Universidad de Sevilla-ICMSE, P.O. Box 1065, 41080 Sevilla (Spain)

    2010-05-15

    Nanocrystallization kinetics is analyzed in the frame of instantaneous growth approximation, which implies that the time required for a crystallite to reach its final size is negligible with respect to the time required for the nanocrystallization process. This approach strongly simplifies the kinetic analysis and allows us to obtain the nucleation rate from both isothermal and non-isothermal nanocrystallization processes. Moreover, as no constraining mechanism is considered but the absence of growth, the results could be discussed in the frame of Johnson-Mehl-Avrami-Kolmogorov theory with a growth index equal to zero. Cellular automata simulations are in agreement with the observed kinetics and microstructure. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  5. Financial Valuation of Mortality Risk via the Instantaneous Sharpe Ratio: Applications to Pricing Pure Endowments

    CERN Document Server

    Milevsky, Moshe A; Young, Virginia R

    2007-01-01

    We develop a theory for pricing non-diversifiable mortality risk in an incomplete market. We do this by assuming that the company issuing a mortality-contingent claim requires compensation for this risk in the form of a pre-specified instantaneous Sharpe ratio. We prove that our ensuing valuation formula satisfies a number of desirable properties. For example, we show that it is subadditive in the number of contracts sold. A key result is that if the hazard rate is stochastic, then the risk-adjusted survival probability is greater than the physical survival probability, even as the number of contracts approaches infinity.

  6. Utilization of Different Variables for the Visualization of Fluid Flows:Application to Instantaneous Channel Flows

    Institute of Scientific and Technical Information of China (English)

    Gérard J. Poitras; L.-Emmanuel Brizzi; Yves Gagnon

    2001-01-01

    The results of different numerical algorithms for the computation of unsteady fluid flows are used to visualize different variables of the flow. In particular, the instantaneous vorticity, velocity and pressure fields, along with streamline plots, are presented as a function of time inside a visualization window of the computational domain.The different forms of visualization are used to analyze the flow inside a two-dimensional channel incorporating an obstacle, which can represent several interesting flows such as the flow over electronic components, heat transfer devices and buildings.

  7. Receive antenna selection for underlay cognitive radio with instantaneous interference constraint

    KAUST Repository

    Hanif, Muhammad Fainan

    2015-06-01

    Receive antenna selection is a low complexity scheme to reap diversity benefits.We analyze the performance of a receive antenna selection scheme in spectrum sharing systems where the antenna that results in highest signal-to-interference plus noise ratio at the secondary receiver is selected to improve the performance of secondary transmission. Exact and asymptotic behaviours of the received SINR are derived for both general and interference limited scenarios over general fading environment. These results are then applied to the outage and average bit error rate analysis when the secondary transmitter changes the transmit power in finite discrete levels to satisfy the instantaneous interference constraint at the primary receiver.

  8. The Chernobyl accident consequences; Consequences de l'accident de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-04-01

    Five teen years later, Tchernobyl remains the symbol of the greater industrial nuclear accident. To take stock on this accident, this paper proposes a chronology of the events and presents the opinion of many international and national organizations. It provides also web sites references concerning the environmental and sanitary consequences of the Tchernobyl accident, the economic actions and propositions for the nuclear safety improvement in the East Europe. (A.L.B.)

  9. Remediation Device and Methods for Hydrate Blockage%水合物堵塞治理工具和方法研究∗

    Institute of Scientific and Technical Information of China (English)

    庞维新; 李清平; 程艳; 王炳明

    2016-01-01

    针对深水油气混输管道中极易生成固体水合物而造成输送管道堵塞的问题,研制了水合物堵塞治理工具样机,并对样机的性能进行了试验验证。该样机主要包括橇块主体、脐带缆系统和测量监控系统。根据水合物堵塞治理工具的设计原理提出了相应的操作流程,并开发了控制软件。试验结果表明,水合物堵塞治理工具和控制系统在水下运行正常,能够完成管线降压和抑制剂注入等规定动作,说明利用该工具可以采用降压、注剂/注热或注剂/注热+降压联合的方法解决油气输送管道中固体水合物堵塞的问题。研究内容对于海底混输管线的安全运行具有指导作用。%The deepwater oil and gas transportation pipelines are prone to generating solid hydrate, causing pipeline blockage issue�To address the hydrate blockage, a hydrate blockage remediation device prototype has been developed and tested for performance verification�The prototype mainly includes skid body, umbilical cable system and measuring and monitoring system�The operational process has been established and the control software has been developed according to hydrate blockage remediation device design principle�The testing results showed that the hydrate blockage remediation device and the control system operated normally underwater, and was able to con⁃duct required process like pipeline depressurization and inhibitor injection, indicating the application of the devel⁃oped device could address the hydrate blockage in oil and gas pipelines by depressurization, inhibitor injection/heat injection or inhibitor injection/heat injection+depressurization methods.

  10. 32 CFR 634.29 - Traffic accident investigation reports.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Traffic accident investigation reports. 634.29... records. Installation law enforcement officials will record traffic accident investigations on Service/DLA... traffic accident investigation reports pertaining to accidents investigated by military police that...

  11. 32 CFR 636.13 - Traffic accident investigation reports.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Traffic accident investigation reports. 636.13... Stewart, Georgia § 636.13 Traffic accident investigation reports. In addition to the requirements in § 634... record traffic accident investigations on DA Form 3946 (Military Police Traffic Accident Report) and DA...

  12. 46 CFR 4.03-1 - Marine casualty or accident.

    Science.gov (United States)

    2010-10-01

    ... States vessel wherever such casualty or accident occurs; or (3) With respect to a foreign tank vessel... 46 Shipping 1 2010-10-01 2010-10-01 false Marine casualty or accident. 4.03-1 Section 4.03-1... AND INVESTIGATIONS Definitions § 4.03-1 Marine casualty or accident. Marine casualty or accident...

  13. 48 CFR 852.236-87 - Accident prevention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Accident prevention. 852... Accident prevention. As prescribed in 836.513, insert the following clause: Accident Prevention (SEP 1993....236-13, Accident Prevention. However, only the Contracting Officer may issue an order to stop all...

  14. Assessment of accident risks in the CRBRP. Volume 2. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-03-01

    Appendices to Volume I include core-related accident-sequence definition, CRBRP risk-assessment sequence-probability determinations, failure-probability data, accident scenario evaluation, radioactive material release analysis, ex-core accident analysis, safety philosophy and design features, calculation of reactor accident consequences, sensitivity study, and risk from fires.

  15. 46 CFR 196.30-5 - Accidents to machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Accidents to machinery. 196.30-5 Section 196.30-5... Reports of Accidents, Repairs, and Unsafe Equipment § 196.30-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use...

  16. 46 CFR 97.30-5 - Accidents to machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Accidents to machinery. 97.30-5 Section 97.30-5 Shipping... Reports of Accidents, Repairs, and Unsafe Equipment § 97.30-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use...

  17. 46 CFR 78.33-5 - Accidents to machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Accidents to machinery. 78.33-5 Section 78.33-5 Shipping... Accidents, Repairs, and Unsafe Equipment § 78.33-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use of the...

  18. Prevention of urethral blockage following semen collection in two species of lemur, Varecia variegata variegata and Lemur catta.

    Science.gov (United States)

    Chatfield, Jenifer; Penfold, Linda

    2007-06-01

    Lemurs are a diverse group of primates comprised of five families, all of which are found only on Madagascar and the Comoro Islands. Of the 60 known species, 17 are endangered and 5 of these are considered critically endangered. The effects of inbreeding on population health and viability have been well described; though negative inbreeding effects can be ameliorated through the introduction of new genetic material. Introduction of new individuals into a population can be extremely challenging because of the highly social nature of lemurs. Semen collection in lemur species is notoriously challenging, as the ejaculate forms a coagulum. During normal breeding, the coagulum forms a copulatory plug in the female. However, this coagulum can present a life-threatening situation when retained in the urethra abnormally following electroejaculation. This study investigates the use of ascorbic acid in preventing urethral blockage in two lemur species during semen collection, demonstrates successful collection of semen by electroejaculation from two species of lemur during the breeding season, and discusses removal of urethral plugs subsequent to semen collection. Semen was collected successfully from all animals. Urethral plugs formed during each collection and were abnormally retained in 2/11 collections. Both plugs were successfully and immediately removed with the use of retropulsion through a urethral catheter. Although the results of this study are encouraging, more investigation is required to establish whether or not this procedure can be safely performed in the field.

  19. Recombination occurs within minutes of replication blockage by RTS1 producing restarted forks that are prone to collapse

    Science.gov (United States)

    Nguyen, Michael O; Jalan, Manisha; Morrow, Carl A; Osman, Fekret; Whitby, Matthew C

    2015-01-01

    The completion of genome duplication during the cell cycle is threatened by the presence of replication fork barriers (RFBs). Following collision with a RFB, replication proteins can dissociate from the stalled fork (fork collapse) rendering it incapable of further DNA synthesis unless recombination intervenes to restart replication. We use time-lapse microscopy and genetic assays to show that recombination is initiated within ∼10 min of replication fork blockage at a site-specific barrier in fission yeast, leading to a restarted fork within ∼60 min, which is only prevented/curtailed by the arrival of the opposing replication fork. The restarted fork is susceptible to further collapse causing hyper-recombination downstream of the barrier. Surprisingly, in our system fork restart is unnecessary for maintaining cell viability. Seemingly, the risk of failing to complete replication prior to mitosis is sufficient to warrant the induction of recombination even though it can cause deleterious genetic change. DOI: http://dx.doi.org/10.7554/eLife.04539.001 PMID:25806683

  20. The epidemiology of bicyclist's collision accidents

    DEFF Research Database (Denmark)

    Larsen, L. B.

    1994-01-01

    of bicyclists and risk situations. The findings should make a basis for preventive programmes in order to decrease the number and severity of bicyclists collision accidents. Data from the emergency room in a 2 year period was combined with data from questionnaires. The study group consisted of 1021 bicyclists...... group of accidents were the collisions with the 'soft' road users (bicyclists, mopeds, and pedestrians) and another group were the collisions with the 'hard' road users (motor vehicles, motorcycles). Preventive measures have to be directed at both these groups of accidents. To decrease the number...... of collision accidents with motor vehicles it is necessary to separate the bicyclists from the 'hard road traffic' especially at crossings. Preventive measures must also be directed at the bicyclists. Information must be given to warn the bicyclists against the risks, not only for collisions with motor...

  1. Review of methodology for accident consequence assessment

    Energy Technology Data Exchange (ETDEWEB)

    Strenge, D.L.; Soldat, J.K.; Watson, E.C.

    1978-09-01

    This report reviews current methodologies for reactor accident consequence analysis and describes areas where modifications are warranted. Methodologies reviewed are: (1) Models in Regulatory Guides 1.109, 1.111 and 1.113 used for evaluation of compliance with 10 CFR 50 Appendix I; (2) Models in Regulatory Guides used for evaluation of consequences from accidents of Classes 3-8; (3) Models for evaluation of Class 9 accidents presented in the Reactor Safety Study; and (4) Models in the Liquid Pathway Generic Study. The review is designed to aid in the ultimate goal of selection of a comprehensive set of models to extend the Class 9 methodology of the Reactor Safety Study to the analysis of Classes 3-8 accidents.

  2. Agricultural implications of the Fukushima nuclear accident

    National Research Council Canada - National Science Library

    Nakanishi, Tomoko M; Tanoi, Keitaro

    2013-01-01

    Following the Fukushima nuclear accident, a large volume of monitoring data has been collected about the soil, air, dust, and seawater, along with data about an immense number of foods supplied to the market...

  3. MELCOR analysis of the TMI-2 accident

    Energy Technology Data Exchange (ETDEWEB)

    Boucheron, E.A.

    1990-01-01

    This paper describes the analysis of the Three Mile Island-2 (TMI-2) standard problem that was performed with MELCOR. The MELCOR computer code is being developed by Sandia National Laboratories for the Nuclear Regulatory Commission for the purpose of analyzing severe accident in nuclear power plants. The primary role of MELCOR is to provide realistic predictions of severe accident phenomena and the radiological source team. The analysis of the TMI-2 standard problem allowed for comparison of the model predictions in MELCOR to plant data and to the results of more mechanistic analyses. This exercise was, therefore valuable for verifying and assessing the models in the code. The major trends in the TMI-2 accident are reasonably well predicted with MELCOR, even with its simplified modeling. Comparison of the calculated and measured results is presented and, based on this comparison, conclusions can be drawn concerning the applicability of MELCOR to severe accident analysis. 5 refs., 10 figs., 3 tabs.

  4. Safety analysis of surface haulage accidents

    Energy Technology Data Exchange (ETDEWEB)

    Randolph, R.F.; Boldt, C.M.K.

    1996-12-31

    Research on improving haulage truck safety, started by the U.S. Bureau of Mines, is being continued by its successors. This paper reports the orientation of the renewed research efforts, beginning with an update on accident data analysis, the role of multiple causes in these accidents, and the search for practical methods for addressing the most important causes. Fatal haulage accidents most often involve loss of control or collisions caused by a variety of factors. Lost-time injuries most often involve sprains or strains to the back or multiple body areas, which can often be attributed to rough roads and the shocks of loading and unloading. Research to reduce these accidents includes improved warning systems, shock isolation for drivers, encouraging seatbelt usage, and general improvements to system and task design.

  5. Review of models applicable to accident aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Glissmeyer, J.A.

    1983-07-01

    Estimations of potential airborne-particle releases are essential in safety assessments of nuclear-fuel facilities. This report is a review of aerosol behavior models that have potential applications for predicting aerosol characteristics in compartments containing accident-generated aerosol sources. Such characterization of the accident-generated aerosols is a necessary step toward estimating their eventual release in any accident scenario. Existing aerosol models can predict the size distribution, concentration, and composition of aerosols as they are acted on by ventilation, diffusion, gravity, coagulation, and other phenomena. Models developed in the fields of fluid mechanics, indoor air pollution, and nuclear-reactor accidents are reviewed with this nuclear fuel facility application in mind. The various capabilities of modeling aerosol behavior are tabulated and discussed, and recommendations are made for applying the models to problems of differing complexity.

  6. Ruthenium release from fuel in accident conditions

    Energy Technology Data Exchange (ETDEWEB)

    Brillant, G.; Marchetto, C.; Plumecocq, W. [Inst. de Radioprotection et de Surete Nucleaire, DPAM, SEMIC, LETR and LIMSI, Saint-Paul-Lez-Durance (France)

    2010-07-01

    During a hypothetical nuclear power plant accident, fission products may be released from the fuel matrix and then reach the containment building and the environment. Ruthenium is a very hazardous fission product that can be highly and rapidly released in some accident scenarios. The impact of the atmosphere redox properties, temperature, and fuel burn-up on the ruthenium release is discussed. In order to improve the evaluation of the radiological impact by accident codes, a model of the ruthenium release from fuel is proposed using thermodynamic equilibrium calculations. In addition, a model of fuel oxidation under air is described. Finally, these models have been integrated in the ASTEC accident code and validation calculations have been performed on several experimental tests. (orig.)

  7. The Chornobyl accident: A comprehensive risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Vargo, G.J. [ed.; Poyarkov, V.; Bar`yakhtar, V.; Kukhar, V.; Los, I.; Kholosha, V.; Shestopalov, V.

    1999-10-01

    The authors, all of whom are Ukrainian and Russian scientists involved with Chornobyl nuclear power plant since the April 1986 accident, present a comprehensive review of the accident. In addition, they present a risk assessment of the remains of the destroyed reactor and its surrounding shelter, Chornobyl radioactive waste storage and disposal sites, and environmental contamination in the region. The authors explore such questions as the risks posed by a collapse of the shelter, radionuclide migration from storage and disposal facilities in the exclusion zone, and transfer from soil to vegetation and its potential regional impact. The answers to these questions provide a scientific basis for the development of countermeasures against the Chornobyl accident in particular and the mitigation of environmental radioactive contamination in general. They also provide an important basis for understanding the human health and ecological risks posed by the accident.

  8. [Severe parachuting accident. Analysis of 122 cases].

    Science.gov (United States)

    Krauss, U; Mischkowsky, T

    1993-06-01

    Based on a population of 122 severely injured patients the causes of paragliding accidents and the patterns of injury are analyzed. A questionnaire is used to establish a sport-specific profile for the paragliding pilot. The lower limbs (55.7%) and the lower parts of the spine (45.9%) are the most frequently injured parts of the body. There is a high risk of multiple injuries after a single accident because of the tremendous axial power. The standard of equipment is good in over 90% of the cases. Insufficient training and failure to take account of geographical and meteorological conditions are the main determinants of accidents sustained by paragliders, most of whom are young. Nevertheless, 80% of our patients want to continue paragliding. Finally some advice is given on how to prevent paragliding accidents and injuries.

  9. Bilateral Shoulder Dislocations Following a Motocross Accident

    National Research Council Canada - National Science Library

    H J Schroepfer; B M Martin; P J Millett

    2017-01-01

    .... A professional motocross racer experienced a high speed traumatic accident which resulted in bilateral shoulder dislocations with a rare associated complete anterosuperior RC tear due to a posterior dislocation...

  10. Severe accident recriticality analyses (SARA)

    DEFF Research Database (Denmark)

    Frid, W.; Højerup, C.F.; Lindholm, I.

    2001-01-01

    three computer codes and to further develop and adapt them for the task. The codes were SIMULATE-3K, APROS and RECRIT. Recriticality analyses were carried out for a number of selected reflooding transients for the Oskarshamn 3 plant in Sweden with SIMULATE-3K and for the Olkiluoto I plant in Finland...... with all three codes. The core initial and boundary conditions prior to recriticality have been studied with the severe accident codes SCDAP/RELAP5, MELCOR and MAAP4. The results of the analyses show that all three codes predict recriticality-both super-prompt power bursts and quasi steady-state power...... generation-for the range of parameters studied, i.e. with core uncovering and heat-up to maximum core temperatures of approximately 1800 K, and water flow rates of 45-2000 kg s(-1) injected into the downcomer. Since recriticality takes place in a small fraction of the core, the power densities are high...

  11. Learning lessons from Natech accidents - the eNATECH accident database

    Science.gov (United States)

    Krausmann, Elisabeth; Girgin, Serkan

    2016-04-01

    When natural hazards impact industrial facilities that house or process hazardous materials, fires, explosions and toxic releases can occur. This type of accident is commonly referred to as Natech accident. In order to prevent the recurrence of accidents or to better mitigate their consequences, lessons-learned type studies using available accident data are usually carried out. Through post-accident analysis, conclusions can be drawn on the most common damage and failure modes and hazmat release paths, particularly vulnerable storage and process equipment, and the hazardous materials most commonly involved in these types of accidents. These analyses also lend themselves to identifying technical and organisational risk-reduction measures that require improvement or are missing. Industrial accident databases are commonly used for retrieving sets of Natech accident case histories for further analysis. These databases contain accident data from the open literature, government authorities or in-company sources. The quality of reported information is not uniform and exhibits different levels of detail and accuracy. This is due to the difficulty of finding qualified information sources, especially in situations where accident reporting by the industry or by authorities is not compulsory, e.g. when spill quantities are below the reporting threshold. Data collection has then to rely on voluntary record keeping often by non-experts. The level of detail is particularly non-uniform for Natech accident data depending on whether the consequences of the Natech event were major or minor, and whether comprehensive information was available for reporting. In addition to the reporting bias towards high-consequence events, industrial accident databases frequently lack information on the severity of the triggering natural hazard, as well as on failure modes that led to the hazmat release. This makes it difficult to reconstruct the dynamics of the accident and renders the development of

  12. APRI-6. Accident Phenomena of Risk Importance

    Energy Technology Data Exchange (ETDEWEB)

    Garis, Ninos; Ljung, J (eds.) (Swedish Radiation Safety Authority, Stockholm (Sweden)); Agrenius, Lennart (ed.) (Agrenius Ingenjoersbyraa AB, Stockholm (Sweden))

    2009-06-15

    Since the early 1980s, nuclear power utilities in Sweden and the Swedish Radiation Safety Authority (SSM) collaborate on the research in severe reactor accidents. In the beginning focus was mostly on strengthening protection against environmental impacts after a severe reactor accident, for example by develop systems for the filtered relief of the reactor containment. Since the early 90s, this focus has shifted to the phenomenological issues of risk-dominant significance. During the years 2006-2008, the partnership continued in the research project APRI-6. The aim was to show whether the solutions adopted in the Swedish strategy for incident management provides adequate protection for the environment. This is done by studying important phenomena in the core melt estimating the amount of radioactivity that can be released to the atmosphere in a severe accident. To achieve these objectives the research has included monitoring of international research on severe accidents and evaluation of results and continued support for research of severe accidents at the Royal Inst. of Technology (KTH) and Chalmers University. The follow-up of international research has promoted the exchange of knowledge and experience and has given access to a wealth of information on various phenomena relevant to events in severe accidents. The continued support to KTH has provided increased knowledge about the possibility of cooling the molten core in the reactor tank and the processes associated with coolability in the confinement and about steam explosions. Support for Chalmers has increased knowledge of the accident chemistry, mainly the behavior of iodine and ruthenium in the containment after an accident.

  13. Health effects resulting from the Chernobyl accident.

    Science.gov (United States)

    Sumner, David

    2007-01-01

    This article reviews the health effects of the Chernobyl accident. The clearest effect to be seen to date is the dramatic increase in thyroid cancer in children. The evidence for increased leukaemia is less clear, but there are indications of increased leukaemia incidence in Russian clean-up workers. There is also evidence of increases in breast cancer, cataract and cardiovascular disease. However, to date the largest public health problem caused by the accident is the mental health impact.

  14. Personality characteristics of the child accident repeater

    OpenAIRE

    Manheimer, Dean I.; Mellinger, Glen D

    1997-01-01

    From 8874 boys and girls aged 4 to 18 in Berkeley-Oakland, California, 684 were selected to represent high-, intermediateor low-accident-liability children, based on records of medically attended injuries. Using data from intensive interviews with mothers supplemented with school records, we found a statistically significant relation between accident liability and indexes of extraversion, daring, roughhousing, and other traits tending to expose children to hazards. Similar relations held for ...

  15. Severe accident testing of electrical penetration assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Clauss, D.B. (Sandia National Labs., Albuquerque, NM (USA))

    1989-11-01

    This report describes the results of tests conducted on three different designs of full-size electrical penetration assemblies (EPAs) that are used in the containment buildings of nuclear power plants. The objective of the tests was to evaluate the behavior of the EPAs under simulated severe accident conditions using steam at elevated temperature and pressure. Leakage, temperature, and cable insulation resistance were monitored throughout the tests. Nuclear-qualified EPAs were produced from D. G. O'Brien, Westinghouse, and Conax. Severe-accident-sequence analysis was used to generate the severe accident conditions (SAC) for a large dry pressurized-water reactor (PWR), a boiling-water reactor (BWR) Mark I drywell, and a BWR Mark III wetwell. Based on a survey conducted by Sandia, each EPA was matched with the severe accident conditions for a specific reactor type. This included the type of containment that a particular EPA design was used in most frequently. Thus, the D. G. O'Brien EPA was chosen for the PWR SAC test, the Westinghouse was chosen for the Mark III test, and the Conax was chosen for the Mark I test. The EPAs were radiation and thermal aged to simulate the effects of a 40-year service life and loss-of-coolant accident (LOCA) before the SAC tests were conducted. The design, test preparations, conduct of the severe accident test, experimental results, posttest observations, and conclusions about the integrity and electrical performance of each EPA tested in this program are described in this report. In general, the leak integrity of the EPAs tested in this program was not compromised by severe accident loads. However, there was significant degradation in the insulation resistance of the cables, which could affect the electrical performance of equipment and devices inside containment at some point during the progression of a severe accident. 10 refs., 165 figs., 16 tabs.

  16. Severe accident risks from external events

    Institute of Scientific and Technical Information of China (English)

    Randall O Gauntt

    2013-01-01

    This paper reviews the early development of design requirements for seismic events in USA early developing nuclear electric generating fleet.Notable safety studies,including WASH-1400,Sandia Siting Study and the NUREG-1150 probabilistic risk study,are briefly reviewed in terms of their relevance to extreme accidents arising from seismic and other severe accident initiators.Specific characteristic about the nature of severe accidents in nuclear power plant (NPP) are reviewed along with present day state-of-art analysis methodologies (methods for estimation of leakages and consequences of releases (MELCOR) and MELCOR accident consequence code system (MACCS)) that are used to evaluate severe accidents and to optimize mitigative and protective actions against such accidents.It is the aim of this paper to make nuclear operating nations aware of the risks that accompany a much needed energy resource and to identify some of the tools,techniques and landmark safety studies that serve to make the technology safer and to maintain vigilance and adequate safety culture for the responsible management of this valuable but unforgiving technology.

  17. FUNDING OF ACCIDENT INSURANCE IN UKRAINE

    Directory of Open Access Journals (Sweden)

    O. Gamankova

    2016-03-01

    Full Text Available The paper deals with the peculiarities of financial provision of public and private accident insurance. Analyzes the methodology of forming insurance premium rates in private accident insurance. The study examines the practice of reforming the financial security of the state social insurance against accidents. The results show need to implement scientifically proven approach to determining premium rates in the state social insurance based on mathematical statistics and actuarial calculations to ensure that such conditions on the one hand, can insure the risk, and the other - to provide the insurer the ability to perform insurance obligations' commitments. One of the promising areas of improvement Accident Insurance determines to define increasing the role of the private sector to create and attraction of investments, financing, reduce costs, and provision of insurance services on insurance against accidents at a qualitatively higher level. The results show the need to consider the usefulness of a mixed provision of services to accident insurance under state or non-state system, and the viability and effectiveness of the combination of these systems.

  18. CURRENT FACTORS OF ROAD ACCIDENTS IN ISFAHAN

    Directory of Open Access Journals (Sweden)

    B AMINMAN SOUR

    2000-06-01

    Full Text Available

    Introduction. Car accident mortality is the third order causes of death in the USA, following cardiovascular diseases and cancers. Given present survival and outcome Iranian data, more than 14,000 patients die annually in road accidents. Having a valid and reliable data could be useful in reduce mortality and morbidity reduction.
    Methods. Twenty five percent of total traumatic patients in Isfahan were selected (N=2809 at the time of study (1997-1998. Forty five percent of them with car accident were asked about causes of accidents and risk factors for the severity and type of injuries were recorded based on International Classification of Disease 10.
    Results. Most of the victims were young (10-20 years old, students and industrial workers. Statistically unreasonable numbers of cars without extension of roads and high ways, using old and unsafe cars will affects on accidents.
    Discussion. In comparison with European and some Asian countries, Iran has unacceptable road accidents and it seems necessary to pay more attention to stop the current increasing data.

     

  19. Concerning the instantaneous mass and the extent of an expanding universe

    CERN Document Server

    Fahr, H J; Heyl, Michael

    2006-01-01

    In this article we want to answer the cosmologically relevant question what, with some good semantic and physical reason, could be called the mass of an infinitely extended, homogeneously matter-filled and expanding universe. To answer this question we produce a space-like sum of instantaneous cosmic energy depositions surrounding equally each spacepoint in the homogeneous universe. We calculate the added-up instantaneous cosmic energy per volume around an arbitrary space point in the expanding universe. To carry out this sum we use as basic metrics an analogy to the inner Schwarzschild metric applied to stars, but this time applied to the spacepoint-related universe. It is then shown that this leads to the added-up proper energy within a sphere of a finite outer critical radius defining the point-related infinity. As a surprise this radius turns out to be reciprocal to the square root of the prevailing average cosmic energy density. The equivalent mass of the universe can then also be calculated and, by the ...

  20. Fast instantaneous center of rotation estimation algorithm for a skied-steered robot

    Science.gov (United States)

    Kniaz, V. V.

    2015-05-01

    Skid-steered robots are widely used as mobile platforms for machine vision systems. However it is hard to achieve a stable motion of such robots along desired trajectory due to an unpredictable wheel slip. It is possible to compensate the unpredictable wheel slip and stabilize the motion of the robot using visual odometry. This paper presents a fast optical flow based algorithm for estimation of instantaneous center of rotation, angular and longitudinal speed of the robot. The proposed algorithm is based on Horn-Schunck variational optical flow estimation method. The instantaneous center of rotation and motion of the robot is estimated by back projection of optical flow field to the ground surface. The developed algorithm was tested using skid-steered mobile robot. The robot is based on a mobile platform that includes two pairs of differential driven motors and a motor controller. Monocular visual odometry system consisting of a singleboard computer and a low cost webcam is mounted on the mobile platform. A state-space model of the robot was derived using standard black-box system identification. The input (commands) and the output (motion) were recorded using a dedicated external motion capture system. The obtained model was used to control the robot without visual odometry data. The paper is concluded with the algorithm quality estimation by comparison of the trajectories estimated by the algorithm with the data from motion capture system.

  1. Compensating for instantaneous signal mixing in transfer entropy analysis of neurobiological time series.

    Science.gov (United States)

    Faes, Luca; Erla, Silvia; Nollo, Giandomenico

    2012-01-01

    The transfer entropy (TE) has recently emerged as a nonlinear model-free tool, framed in information theory, to detect directed interactions in coupled processes. Unfortunately, when applied to neurobiological time series TE is biased by signal cross-talk due to volume conduction. To compensate for this bias, in this study we introduce a modified TE measure which accounts for possible instantaneous effects between the analyzed time series. The new measure, denoted as compensated TE (cTE), is tested on simulated time series reproducing conditions typical of neuroscience applications, and on real magnetoencephalographic (MEG) multi-trial data measured during a visuo-tactile cognitive experiment. Simulations show that cTE performs similarly to TE in the absence of signal cross-talk, and prevents false positive detection of information transfer in the case of instantaneous mixing of uncoupled signals. When applied to MEG data, cTE detects significant information flow from the visual cortex to the somatosensory area during task execution, suggesting the activation of mechanisms of multisensory integration.

  2. Diurnal cycle of the dust instantaneous direct radiative forcing over the Arabian Peninsula

    KAUST Repository

    Osipov, S.

    2015-08-27

    In this study we attempted to better quantify radiative effects of dust over the Arabian Peninsula and their dependence on input parameters. For this purpose we have developed a stand-alone column radiation transport model coupled with the Mie, T-matrix and geometric optics calculations and driven by reanalysis meteorological fields and atmospheric composition. Numerical experiments were carried out for a wide range of aerosol optical depths, including extreme values developed during the dust storm on 18–20 March 2012. Comprehensive ground-based observations and satellite retrievals were used to estimate aerosol optical properties, validate calculations and carry out radiation closure. The broadband surface albedo, fluxes at the bottom and top of the atmosphere as well as instantaneous dust radiative forcing were estimated both from the model and observations. Diurnal cycle of the shortwave instantaneous dust direct radiative forcing was studied for a range of aerosol and surface characteristics representative of the Arabian Peninsula. Mechanisms and parameters responsible for diurnal variability of the radiative forcing were evaluated. We found that intrinsic variability of the surface albedo and its dependence on atmospheric conditions, along with anisotropic aerosol scattering, are mostly responsible for diurnal effects.

  3. Instantaneous x-ray radiation energy from laser produced polystyrene plasmas for shock ignition conditions

    Energy Technology Data Exchange (ETDEWEB)

    Shang, Wanli; Wei, Huiyue; Li, Zhichao; Yi, Rongqing; Zhu, Tuo; Song, Tianmin; Huang, Chengwu; Yang, Jiamin [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China)

    2013-10-15

    Laser target energy coupling mechanism is crucial in the shock ignition (SI) scheme, and x-ray radiation energy is a non-negligible portion of the laser produced plasma energy. To evaluate the x-ray radiation energy amount at conditions relevant to SI scheme, instantaneous x-ray radiation energy is investigated experimentally with continuum phase plates smoothed lasers irradiating layer polystyrene targets. Comparative laser pulses without and with shock spike are employed. With the measured x-ray angular distribution, full space x-ray radiation energy and conversion efficiency are observed. Instantaneous scaling law of x-ray conversion efficiency is obtained as a function of laser intensity and time. It should be pointed out that the scaling law is available for any laser pulse shape and intensity, with which irradiates polystyrene planar target with intensity from 2 × 10{sup 14} to 1.8 × 10{sup 15} W/cm{sup 2}. Numerical analysis of the laser energy transformation is performed, and the simulation results agree with the experimental data.

  4. Assessing instantaneous energy in the EEG: a non-negative, frequency-weighted energy operator.

    Science.gov (United States)

    O'Toole, John M; Temko, Andriy; Stevenson, Nathan

    2014-01-01

    Signal processing measures of instantaneous energy typically include only amplitude information. But measures that include both amplitude and frequency do better at assessing the energy required by the system to generate the signal, making them more sensitive measures to include in electroencephalogram (EEG) analysis. The Teager-Kaiser operator is a frequency-weighted measure that is frequently used in EEG analysis, although the operator is poorly defined in terms of common signal processing concepts. We propose an alternative frequency-weighted energy measure that uses the envelope of the derivative of the signal. This simple envelope- derivative operator has the advantage of being nonnegative, which when applied to a detection application in newborn EEG improves performance over the Teager-Kaiser operator: without post-processing filters, area-under the receiver-operating characteristic curve (AUC) is 0.57 for the Teager-Kaiser operator and 0.80 for the envelope-derivative operator. The envelope-derivative operator also satisfies important properties, similar to the Teager-Kaiser operator, such as tracking instantaneous amplitude and frequency.

  5. Preliminary verification of instantaneous air temperature estimation for clear sky conditions based on SEBAL

    Science.gov (United States)

    Zhu, Shanyou; Zhou, Chuxuan; Zhang, Guixin; Zhang, Hailong; Hua, Junwei

    2017-02-01

    Spatially distributed near surface air temperature at the height of 2 m is an important input parameter for the land surface models. It is of great significance in both theoretical research and practical applications to retrieve instantaneous air temperature data from remote sensing observations. An approach based on Surface Energy Balance Algorithm for Land (SEBAL) to retrieve air temperature under clear sky conditions is presented. Taking the meteorological measurement data at one station as the reference and remotely sensed data as the model input, the research estimates the air temperature by using an iterative computation. The method was applied to the area of Jiangsu province for nine scenes by using MODIS data products, as well as part of Fujian province, China based on four scenes of Landsat 8 imagery. Comparing the air temperature estimated from the proposed method with that of the meteorological station measurement, results show that the root mean square error is 1.7 and 2.6 °C at 1000 and 30 m spatial resolution respectively. Sensitivity analysis of influencing factors reveals that land surface temperature is the most sensitive to the estimation precision. Research results indicate that the method has great potentiality to be used to estimate instantaneous air temperature distribution under clear sky conditions.

  6. A new strategy of instantaneous angular speed extraction and its application to multistage gearbox fault diagnosis

    Science.gov (United States)

    Li, Bing; Zhang, Xining

    2017-05-01

    Owing to its unique benefits, Instantaneous Angular Speed (IAS) has become the focus of a great deal of research for monitoring mechanical parts of rotating machines in the past few years. However, the efficacy of IAS-based signal processing techniques essentially depends on the estimation method of IAS and the complexity of the mechanical system. When it is applied to complex systems like turbines, gearboxes, conventional IAS itself still has some flaws and insufficiencies such as longer data stream, quantization noise and structural noise. In order to address these issues, this paper proposes an alternative IAS estimation approach named Instantaneous Angular Phase Demodulation (IAPD) IAS together with an improved procedure involving signal reconstruction, empirical mode decomposition (EMD) and envelope analysis. Thereafter, two kinds of multistage gearboxes under different working conditions are developed to experimentally demonstrate the accuracy and effectiveness of the new IAS measurement. Analysis results suggest that the quantization noise can be significantly reduced or even avoided in the IAPD-IAS signal compared with the conventional IAS signal. Moreover, by means of the new procedure, the computational efficiency can be greatly improved and fault characteristics are dramatically enhanced in the envelope spectrum where deterministic frequency component and its harmonics corresponding to fault characteristics are displayed clearly.

  7. New Approach to Optimize the Apfs Placement Based on Instantaneous Reactive Power Theory by Genetic Algorithm

    Science.gov (United States)

    Hashemi-Dezaki, Hamed; Mohammadalizadeh-Shabestary, Masoud; Askarian-Abyaneh, Hossein; Rezaei-Jegarluei, Mohammad

    2014-01-01

    In electrical distribution systems, a great amount of power are wasting across the lines, also nowadays power factors, voltage profiles and total harmonic distortions (THDs) of most loads are not as would be desired. So these important parameters of a system play highly important role in wasting money and energy, and besides both consumers and sources are suffering from a high rate of distortions and even instabilities. Active power filters (APFs) are innovative ideas for solving of this adversity which have recently used instantaneous reactive power theory. In this paper, a novel method is proposed to optimize the allocation of APFs. The introduced method is based on the instantaneous reactive power theory in vectorial representation. By use of this representation, it is possible to asses different compensation strategies. Also, APFs proper placement in the system plays a crucial role in either reducing the losses costs and power quality improvement. To optimize the APFs placement, a new objective function has been defined on the basis of five terms: total losses, power factor, voltage profile, THD and cost. Genetic algorithm has been used to solve the optimization problem. The results of applying this method to a distribution network illustrate the method advantages.

  8. Instantaneous phase shift of annual subsurface temperature cycles derived by the Hilbert-Huang transform

    Science.gov (United States)

    Sun, Yang-Yi; Chen, Chieh-Hung; Liu, Jann-Yenq; Wang, Chung-Ho; Chen, Deng-Lung

    2015-03-01

    This study uses the Hilbert-Huang transform to compute the instantaneous (daily) phase shift between temperature signals at the ground surface and at a depth of 5 m. This approach is not restricted to the stationary harmonic surface temperature assumptions invoked by analytical solutions. The annual cycles are extracted from the ground surface temperatures and the shallow subsurface temperatures at 5 m depth recorded at the Hualien (23.98°N, 121.61°E) and Ilan (24.77°N, 121.75°E) meteorology stations of Central Weather Bureau in Taiwan from 1952 to 2008. Significant reductions in the phase shift and increases in the estimated thermal diffusivity from 1980s to 1990s are found and suggest that the recent warming of the Pacific Decadal Oscillation may affect heat transport in the subsurface environment. The marginal spectra of the instantaneous phase shifts and the precipitation intensity records at Hualien and Ilan reveal that precipitation may play a role in the evolution of seasonal variation in shallow subsurface heat transport.

  9. [Real time diagnostics of instantaneous temperature of combustion and explosion process by modern spectroscopy].

    Science.gov (United States)

    Zhou, Xue-tie; Wang, Jun-de; Li, Yan; Liu, Da-bing

    2003-04-01

    The combustion temperature is one of the important parameters to express flame combustion and explosion characteristics. It will effectively guide the design and manufacture of new model explosives, industrial explosive materials, and weapons. The recent developments and applications of real time diagnostics of instantaneous temperature of combustion and explosion processes by modern spectroscopic methods, such as atomic absorption-emission method, atomic emission two-line spectroscopy, atomic emission multiline spectroscopy, molecular rotation-vibration spectroscopy, coherent anti-stokes Raman scattering (CARS) and plane laser-induced fluorescence (PLIF), were reviewed in this paper. The maximum time resolution of atomic absorption-emission method is 25 microseconds. The time resolution of atomic emission two-line spectroscopy can reach 0.1 microsecond. These two methods can completely suit the need of real time and instantaneous temperature diagnostics of violent explosion and flame combustion. Other methods will also provide new effective research methods for the processes and characteristics of combustion, flame and explosion.

  10. Valuation of Mortality Risk via the Instantaneous Sharpe Ratio: Applications to Life Annuities

    CERN Document Server

    Bayraktar, Erhan; Promislow, David; Young, Virginia

    2008-01-01

    We develop a theory for valuing non-diversifiable mortality risk in an incomplete market. We do this by assuming that the company issuing a mortality-contingent claim requires compensation for this risk in the form of a pre-specified instantaneous Sharpe ratio. We apply our method to value life annuities. One result of our paper is that the value of the life annuity is {\\it identical} to the upper good deal bound of Cochrane and Sa\\'{a}-Requejo (2000) and of Bj\\"{o}rk and Slinko (2006) applied to our setting. A second result of our paper is that the value per contract solves a {\\it linear} partial differential equation as the number of contracts approaches infinity. One can represent the limiting value as an expectation with respect to an equivalent martingale measure (as in Blanchet-Scalliet, El Karoui, and Martellini (2005)), and from this representation, one can interpret the instantaneous Sharpe ratio as an annuity market's price of mortality risk.

  11. Description and clinical studies of a device for the instantaneous detection of office-place stress.

    Science.gov (United States)

    Levine, James A; Pavlidis, Ioannis T; MacBride, Leslie; Zhu, Zhen; Tsiamyrtzis, Panagiotis

    2009-01-01

    Occupational stress is universally experienced and is emerging as a major risk factor for physical and mental illness and a key factor in poor work performance and low job satisfaction. However, the technology does not currently exist to unobtrusively measure occupational stress in real-time. Here, we describe the design and clinical validation of an automated high-definition thermal imaging system that can be used to quantify human stress, remotely and instantaneously. Healthy human subjects underwent a computer-based version of the Stroop-color conflict test, which is a validated stress provocation test, in an experimental office facility. In separate experiments, the same subjects completed a mental arithmetic challenge. The thermal signal associated with stress provocation is near-instantaneous corrugator warming. The stress response was detected in all subjects for all stress-events compared to the respective baselines. Furthermore, there was remarkable inter-individual preservation of the corrugator signal with stress R(2) = 0.96, Pthermal imaging can be used for real-time detection of stress provocation. This technology may prove to be of help in ameliorating office-place stress.

  12. Joint location, inventory, and preservation decisions for non-instantaneous deterioration items under delay in payments

    Science.gov (United States)

    Tsao, Yu-Chung

    2016-02-01

    This study models a joint location, inventory and preservation decision-making problem for non-instantaneous deteriorating items under delay in payments. An outside supplier provides a credit period to the wholesaler which has a distribution system with distribution centres (DCs). The non-instantaneous deteriorating means no deterioration occurs in the earlier stage, which is very useful for items such as fresh food and fruits. This paper also considers that the deteriorating rate will decrease and the reservation cost will increase as the preservation effort increases. Therefore, how much preservation effort should be made is a crucial decision. The objective of this paper is to determine the optimal locations and number of DCs, the optimal replenishment cycle time at DCs, and the optimal preservation effort simultaneously such that the total network profit is maximised. The problem is formulated as piecewise nonlinear functions and has three different cases. Algorithms based on piecewise nonlinear optimisation are provided to solve the joint location and inventory problem for all cases. Computational analysis illustrates the solution procedures and the impacts of the related parameters on decisions and profits. The results of this study can serve as references for business managers or administrators.

  13. The excess proton at the air-water interface: The role of instantaneous liquid interfaces

    Science.gov (United States)

    Giberti, Federico; Hassanali, Ali A.

    2017-06-01

    The magnitude of the pH of the surface of water continues to be a contentious topic in the physical chemistry of aqueous interfaces. Recent theoretical studies have shown little or no preference for the proton to be at the surface compared to the bulk. Using ab initio molecular dynamics simulations, we revisit the propensity of the excess proton for the air-water interface with a particular focus on the role of instantaneous liquid interfaces. We find a more pronounced presence for the proton to be at the air-water interface. The enhanced water structuring around the proton results in the presence of proton wires that run parallel to the surface as well as a hydrophobic environment made up of under-coordinated topological defect water molecules, both of which create favorable conditions for proton confinement at the surface. The Grotthuss mechanism within the structured water layer involves a mixture of both concerted and closely spaced stepwise proton hops. The proton makes excursions within the first solvation layer either in proximity to or along the instantaneous interface.

  14. [Drivers of advanced age in traffic accidents].

    Science.gov (United States)

    Bilban, Marjan

    2002-12-01

    The elderly are vulnerable and potentially unpredictable active participants in traffic who deserve special attention. Longer life expectancy entails a greater number of senior drivers, that is, persons with various health problems and difficulties accompanying old age. At the turn of the millennium, the share of population aged 65 or more in Slovenia was around 13%, and in 25 years it will be near as much as 19%. The share of drivers from this age group was 28% a year ago, and it is expected to reach about 54%. Numerous studies have shown that there are many differences in driving attitude between the young and the elderly. The young are by large active victims, and their main offense and cause of accident is speeding, while the elderly are more passive and their main offense is ignoring and enforcing the right of way. This paper focuses on the differences in the occurrence and type of injuries between the young and the elderly drivers, based on an analysis of all road accidents in Slovenia in the period between 1998-2000. Older people (over 65) caused only 4.7% of all road accidents (16.7% of all accidents involving pedestrians, 11.5% of all involving cyclists, 2.7% involving motorcyclists and 5% of all accidents involving car drivers). Of all accidents, 89.3% were without injuries, and the fatal outcome was registered in 0.4% accidents. Among the elderly (65-74 years of age), however, this share was 1%, and rising to 2.7% with the age 75 and above. By calculating the weight index, which discriminates between minor and severe injuries, and the fatal outcome, it was established that age groups 65-74 and > or = 75 cause three and five times greater damage, respectively than age groups from 18 to 54 years. With years, psychophysical changes lead to a drop in driving ability, which in turn increases the risk of road accidents. It is true that elderly people cause less traffic accidents (and also drive less) than the young, but when they are involved in an accident

  15. Exploring Environmental Effects of Accidents During Marine Transport of Dangerous Goods by Use of Accident Descriptions

    DEFF Research Database (Denmark)

    Rømer, Hans Gottberg; Haastrup, P.; Petersen, H J Styhr

    1996-01-01

    On the basis of 1776 descriptions of water transport accidents involving dangerous goods, environmental problems in connection with releases of this kind are described and discussed. It was found that most detailed descriptions of environmental consequences concerned oil accidents, although most...

  16. Blockage of SSRP1/Ets-1/Pim-3 signalling enhances chemosensitivity of nasopharyngeal carcinoma to docetaxel in vitro.

    Science.gov (United States)

    Ai, Jingang; Li, Wei; Zeng, Ruifang; Xie, Zuozhong; Liu, Honghui; Hou, Minghua; Tan, Guolin

    2016-10-01

    Nasopharyngeal carcinoma (NPC) is a rare cancer in most parts of the world, but is prevalent in South China area. Besides, therapeutic outcome is still unsatisfactory for patients with refractory and relapsed NPC, even though receiving a second line of docetaxel-based chemotherapy. These reasons require a better understanding of mechanisms underlying the carcinogenesis, malignancy and chemoresistance. In the basis of our previous finding of SSRP1 over-expression in NPC cell lines, this study continuously discovered up-regulated Ets-1, phosphor-Ets-1 and Pim-3 in NPC tissues with immunohistochemistry assay and revealed a close correlation of these up-regulated proteins with NPC proliferation and invasion. Using gene-silencing technology followed by western blot and immunocytochemistry detections, SSRP1 was found to facilitate the translocation of phosphor-Ets-1 from cytoplasm to cell nucleus, but have marginal effect on Ets-1 expression and phosphorylation. Pim-3 was positively regulated by Ets-1. In NPC HNE-1 cells, all SSRP1, Ets-1 and Pim-3 knockdown diminished the cell proliferation, enhanced the apoptosis, as well as inhibited the autophagy, invasion and clonogenicity in the presence or absence of docetaxel at IC25. Exposure of HNE-1 cells to docetaxel (IC25) alone had modest effect on cell proliferation and autophagy, and was not as effective as docetaxel treatment after knockdown of SSRP1, Ets-1 or Pim-3 on induction of the apoptosis and on inhibition of the invasion and clonogenicity. Our data indicate that SSRP1/Ets-1/Pim-3 signalling is tightly associated with the proliferation, apoptosis, autophagy, invasion and clonogenicity of NPC cells, and blockage of this signalling facilitates chemosensitivity of the cells to docetaxel. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Reactor Safety Gap Evaluation of Accident Tolerant Components and Severe Accident Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, Mitchell T. [Argonne National Lab. (ANL), Argonne, IL (United States); Bunt, R. [Southern Nuclear, Atlanta, GA (United States); Corradini, M. [Univ. of Wisconsin, Madison, WI (United States); Ellison, Paul B. [GE Power and Water, Duluth, GA (United States); Francis, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Gabor, John D. [Erin Engineering, Walnut Creek, CA (United States); Gauntt, R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Henry, C. [Fauske and Associates, Burr Ridge, IL (United States); Linthicum, R. [Exelon Corp., Chicago, IL (United States); Luangdilok, W. [Fauske and Associates, Burr Ridge, IL (United States); Lutz, R. [PWR Owners Group (PWROG); Paik, C. [Fauske and Associates, Burr Ridge, IL (United States); Plys, M. [Fauske and Associates, Burr Ridge, IL (United States); Rabiti, Cristian [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rempe, J. [Rempe and Associates LLC, Idaho Falls, ID (United States); Robb, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Wachowiak, R. [Electric Power Research Inst. (EPRI), Knovville, TN (United States)

    2015-01-31

    The overall objective of this study was to conduct a technology gap evaluation on accident tolerant components and severe accident analysis methodologies with the goal of identifying any data and/or knowledge gaps that may exist, given the current state of light water reactor (LWR) severe accident research, and additionally augmented by insights obtained from the Fukushima accident. The ultimate benefit of this activity is that the results can be used to refine the Department of Energy’s (DOE) Reactor Safety Technology (RST) research and development (R&D) program plan to address key knowledge gaps in severe accident phenomena and analyses that affect reactor safety and that are not currently being addressed by the industry or the Nuclear Regulatory Commission (NRC).

  18. Biomass accident investigations – missed opportunities for learning and accident prevention

    DEFF Research Database (Denmark)

    Hedlund, Frank Huess

    2017-01-01

    selected serious accidents involving biogas and wood pellets in Denmark and argues that such opportunities for learning were missed because accident investigations were superficial, follow-up incomplete and information sharing absent. In one particularly distressing case, a facility saw a repeat accident......, this time with fatal outcome, still without any learning taking place. The paper presents some information on other biomass accidents in Denmark, mostly involving biogas from anaerobic digestion. Details are lacking however, precisely because the accidents were insufficiently investigated and results...... not communicated. The biomass industry needs to pay more attention to safety. Utmost care should be taken to avoid so-called mediashifting i.e. that the resolution of a problem within one domain, the environmental, creates a new problem in another, the workplace safety domain....

  19. Improved tilt sensing in an LGS-based tomographic AO system based on instantaneous PSF estimation

    Science.gov (United States)

    Veran, Jean-Pierre

    2013-12-01

    Laser guide star (LGS)-based tomographic AO systems, such as Multi-Conjugate AO (MCAO), Multi-Object AO (MOAO) and Laser Tomography AO (LTAO), require natural guide stars (NGSs) to sense tip-tilt (TT) and possibly other low order modes, to get rid of the LGS-tilt indetermination problem. For example, NFIRAOS, the first-light facility MCAO system for the Thirty Meter Telescope requires three NGSs, in addition to six LGSs: two to measure TT and one to measure TT and defocus. In order to improve sky coverage, these NGSs are selected in a so-called technical field (2 arcmin in diameter for NFIRAOS), which is much larger than the on-axis science field (17x17 arcsec for NFIRAOS), on which the AO correction is optimized. Most times, the NGSs are far off-axis and thus poorly corrected by the high-order AO loop, resulting in spots with low contrast and high speckle noise. Accurately finding the position of such spots is difficult, even with advanced methods such as matched-filtering or correlation, because these methods rely on the knowledge of an average spot image, which is quite different from the instantaneous spot image, especially in case of poor correction. This results in poor tilt estimation, which, ultimately, impacts sky coverage. We propose to improve the estimation of the position of the NGS spots by using, for each frame, a current estimate of the instantaneous spot profile instead of an average profile. This estimate can be readily obtained by tracing wavefront errors in the direction of the NGS through the turbulence volume. The latter is already computed by the tomographic process from the LGS measurements as part of the high order AO loop. Computing such a wavefront estimate has actually already been proposed for the purpose of driving a deformable mirror (DM) in each NGS WFS, to optically correct the NGS spot, which does lead to improved centroiding accuracy. Our approach, however, is much simpler, because it does not require the complication of extra DMs

  20. The oxidation of uranium hydride during its instantaneous or gradual exposure to oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Glascott, J., E-mail: joe.glascott@awe.co.uk; Findlay, I.M.

    2015-11-15

    The oxidation behaviour of uranium hydride when exposed to oxygen gas either gradually or instantaneously at an ambient temperature of approximately 37 °C has been investigated. The proportion of the sample converted to oxide and the mean hydride mound temperature rise accompanying the oxidation process were recorded. Pressure changes in the reaction cell were used to deduce the nature of the oxide generated during the oxidation process and the nature of the gaseous reaction products. For the gradual oxidation of the hydride, typically only about 15% of the hydride mass was converted to oxide during the initial period of oxidation defined by an observed temperature excursion lasting a finite time; during this oxidation period it is concluded that, despite the only moderate recoded mean temperature rises, the generated oxide is U{sub 3}O{sub 8} rather than UO{sub 2}. Typically also for such gradual exposure experiments, hydrogen was the principal gaseous reaction product with negligible water being produced. For the instantaneous exposure of the hydride to oxygen, much higher hydride mound mean temperature rises were recorded but the proportion of hydride converted to oxide was quite variable and apparently dependent on several experimental variables; for these experiments, although hydrogen was a major reaction product typically some water was also produced. The boundary between pyrophoric and non-pyrophoric oxidation of uranium hydride for given oxidising conditions is discussed in terms of a calculated particle “thermal runaway temperature”. - Highlights: • Only about 15% of UH{sub 3} is oxidised on its gradual exposure to oxygen. • During the gradual exposure of UH{sub 3} to oxygen U{sub 3}O{sub 8} rather than UO{sub 2} is generated. • For such gradual exposure, predominantly H{sub 2} rather than H{sub 2}O was generated. • For the instantaneous exposure of UH{sub 3} to O{sub 2} the amount oxidised was variable. • For these experiments, H{sub 2

  1. Accident history, risk perception and traffic safe behaviour.

    Science.gov (United States)

    Ngueutsa, Robert; Kouabenan, Dongo Rémi

    2017-09-01

    This study clarifies the associations between accident history, perception of the riskiness of road travel and traffic safety behaviours by taking into account the number and severity of accidents experienced. A sample of 525 road users in Cameroon answered a questionnaire comprising items on perception of risk, safe behaviour and personal accident history. Participants who reported involvement in more than three accidents or involvement in a severe accident perceived road travel as less risky and also reported behaving less safely compared with those involved in fewer, or less severe accidents. The results have practical implications for the prevention of traffic accidents. Practitioner Summary: The associations between accident history, perceived risk of road travel and safe behaviour were investigated using self-report questionnaire data. Participants involved in more than three accidents, or in severe accidents, perceived road travel as less risky and also reported more unsafe behaviour compared with those involved in fewer, or less severe accidents. Campaigns targeting people with a less serious, less extensive accident history should aim to increase awareness of hazards and the potential severity of their consequences, as well as emphasising how easy it is to take the recommended preventive actions. Campaigns targeting those involved in more frequent accidents, and survivors of serious accidents, should address feelings of invulnerability and helplessness.

  2. Iodine behaviour in severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, L.M.C.; Grindon, E.; Handy, B.J.; Sutherland, L. [NNC Ltd., Knutsford (United Kingdom); Bruns, W.G.; Sims, H.E. [AEA Technology, Harwell (United Kingdom); Dickinson, S. [AEA Technology, Winfrith (United Kingdom); Hueber, C.; Jacquemain, D. [IPSN/CEA, Cadarache, Saint Paul-Lez-Durance (France)

    1996-12-01

    A description is given of analyses which identify which aspects of the modelling and data are most important in evaluating the release of radioactive iodine to the environment following a potential severe accident at a PWR and which identify the major uncertainties which affect that release. Three iodine codes are used namely INSPECT, IODE and IMPAIR, and their predictions are compared with those of the PSA code MAAP. INSPECT is a mechanistic code which models iodine behaviour in the aqueous aerosol, spray water and sump water, and the partitioning of volatile species between the aqueous phases and containment gas space. Organic iodine is not modelled. IODE and IMPAIR are semi-empirical codes which do not model iodine behaviour in the aqueous aerosol, but model organic iodine. The fault sequences addressed are based on analyses for the Sizewell `B` design. Two types of sequence have been analysed.: (a) those in which a major release of fission products from the primary circuit to the containment occur, e.g. a large LOCAS, (b) those where the release by-passes the containment, e.g. a leak into the auxiliary building. In the analysis of the LOCA sequences where the pH of the sump is controlled to be a value of 8 or greater, all three codes predict that the oxidation of iodine to produce gas phase species does not make a significant contribution to the source term due to leakage from the reactor building and that the latter is dominated by iodide in the aerosol. In the case where the pH of the sump is not controlled, it is found that the proportion of gas phase iodine increases significantly, although the cumulative leakage predicted by all three codes is not significantly different from that predicted by MAAP. The radiolytic production of nitric acid could be a major factor in determining the pH, and if the pH were reduced, the codes predict an increase in gas phase iodine species leaked from the containment. (author) 4 figs., 7 tabs., 13 refs.

  3. Fatal accidents among Danes with multiple sclerosis

    DEFF Research Database (Denmark)

    Brønnum-Hansen, Henrik; Hansen, Thomas; Koch-Henriksen, Nils

    2006-01-01

    We compared the rate of fatal accidents among Danes with multiple sclerosis (MS) with that of the general population. The study was based on linkage of the Danish Multiple Sclerosis Registry to the Cause of Death Registry and covered all 10174 persons in whom MS was diagnosed during the period 1953......-1996. The end of follow-up was 1 January 1999. We calculated standardized mortality ratios (SMRs) for various types of fatal accidents. A total of 76 persons (48 men and 28 women) died from accidents, whereas the expected number of fatalities from such causes was 55.7 (31.4 men and 24.3 women). Thus, the risk...... for death from accidents among persons with MS was 37% higher than that of the general population (SMR = 1.37). We found no significant excess risk for fatal road accidents (SMR = 0.80). The risk for falls was elevated (SMR = 1.29) but not statistically significantly so. The risks were particularly high...

  4. Urine Blockage in Newborns

    Science.gov (United States)

    ... show enlarged kidneys, ureters, or bladders in babies. Amniocentesis. Amniocentesis is a procedure in which amniotic fluid is ... these tests. Ultrasound exams during pregnancy are routine. Amniocentesis and CVS are recommended only when a risk ...

  5. Transmit Antenna Selection for Underlay Cognitive Radio with Instantaneous Interference Constraint

    KAUST Repository

    Hanif, Muhammad

    2016-03-28

    Cognitive radio (CR) technology addresses the problem of spectrum under-utilization. In underlay CR mode, the secondary users are allowed to communicate provided that their transmission is not detrimental to primary user communication. Transmit antenna selection is one of the low-complexity methods to increase the capacity of wireless communication systems. In this article, we propose and analyze the performance benefit of a transmit antenna selection scheme for underlay secondary system that ensures the instantaneous interference caused by the secondary transmitter to the primary receiver is below a predetermined level. Closed-form expressions of the secondary link outage probability, higher order amount of fading, and ergodic capacity are derived for the proposed scheme. Monte-carlo simulations are also carried out to confirm various mathematical results presented in this article.

  6. Mammalian energetics. Instantaneous energetics of puma kills reveal advantage of felid sneak attacks.

    Science.gov (United States)

    Williams, Terrie M; Wolfe, Lisa; Davis, Tracy; Kendall, Traci; Richter, Beau; Wang, Yiwei; Bryce, Caleb; Elkaim, Gabriel Hugh; Wilmers, Christopher C

    2014-10-03

    Pumas (Puma concolor) live in diverse, often rugged, complex habitats. The energy they expend for hunting must account for this complexity but is difficult to measure for this and other large, cryptic carnivores. We developed and deployed a physiological SMART (species movement, acceleration, and radio tracking) collar that used accelerometry to continuously monitor energetics, movements, and behavior of free-ranging pumas. This felid species displayed marked individuality in predatory activities, ranging from low-cost sit-and-wait behaviors to constant movements with energetic costs averaging 2.3 times those predicted for running mammals. Pumas reduce these costs by remaining cryptic and precisely matching maximum pouncing force (overall dynamic body acceleration = 5.3 to 16.1g) to prey size. Such instantaneous energetics help to explain why most felids stalk and pounce, and their analysis represents a powerful approach for accurately forecasting resource demands required for survival by large, mobile predators.

  7. Pricing Life Insurance under Stochastic Mortality via the Instantaneous Sharpe Ratio: Theorems and Proofs

    CERN Document Server

    Young, Virginia R

    2007-01-01

    We develop a pricing rule for life insurance under stochastic mortality in an incomplete market by assuming that the insurance company requires compensation for its risk in the form of a pre-specified instantaneous Sharpe ratio. Our valuation formula satisfies a number of desirable properties, many of which it shares with the standard deviation premium principle. The major result of the paper is that the price per contract solves a linear partial differential equation as the number of contracts approaches infinity. One can interpret the limiting price as an expectation with respect to an equivalent martingale measure. Another important result is that if the hazard rate is stochastic, then the risk-adjusted premium is greater than the net premium, even as the number of contracts approaches infinity. We present a numerical example to illustrate our results, along with the corresponding algorithms.

  8. Instantaneous starburst of the massive clusters Westerlund 1 and NGC 3603 YC

    CERN Document Server

    Kudryavtseva, Natalia; Gennaro, Mario; Rochau, Boyke; Stolte, Andrea; Andersen, Morten; Da Rio, Nicola; Henning, Thomas; Tognelli, Emanuele; Hogg, David; Clark, Simon; Water, Rens

    2012-01-01

    We present a new method to determine the age spread of resolved stellar populations in a starburst cluster. The method relies on a two-step process. In the first step, kinematic members of the cluster are identified based on multi-epoch astrometric monitoring. In the second step, a Bayesian analysis is carried out, comparing the observed photometric sequence of cluster members with sets of theoretical isochrones. When applying this methodology to optical and near-infrared high angular resolution Hubble Space Telescope (HST) and adaptive optics observations of the ~5 Myr old starburst cluster Westerlund 1 and ~2 Myr old starburst cluster NGC 3603 YC, we derive upper limits for the age spreads of 0.4 and 0.1 Myr, respectively. The results strongly suggest that star formation in these starburst clusters happened almost instantaneously.

  9. Existence,uniqueness and ergodicity of Markov branching processes with immigration and instantaneous resurrection

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We consider a modified Markov branching process incorporating with both state-independent immigration and instantaneous resurrection.The existence criterion of the process is firstly considered.We prove that if the sum of the resurrection rates is finite,then there does not exist any process.An existence criterion is then established when the sum of the resurrection rates is infinite.Some equivalent criteria,possessing the advantage of being easily checked,are obtained for the latter case.The uniqueness criterion for such process is also investigated.We prove that although there exist infinitely many of them,there always exists a unique honest process for a given q-matrix.This unique honest process is then constructed.The ergodicity property of this honest process is analysed in detail.We prove that this honest process is always ergodic and the explicit expression for the equilibrium distribution is established.

  10. Optimal pricing and replenishment policies for instantaneous deteriorating items with backlogging and trade credit under inflation

    Science.gov (United States)

    Sundara Rajan, R.; Uthayakumar, R.

    2017-04-01

    In this paper we develop an economic order quantity model to investigate the optimal replenishment policies for instantaneous deteriorating items under inflation and trade credit. Demand rate is a linear function of selling price and decreases negative exponentially with time over a finite planning horizon. Shortages are allowed and partially backlogged. Under these conditions, we model the retailer's inventory system as a profit maximization problem to determine the optimal selling price, optimal order quantity and optimal replenishment time. An easy-to-use algorithm is developed to determine the optimal replenishment policies for the retailer. We also provide optimal present value of profit when shortages are completely backlogged as a special case. Numerical examples are presented to illustrate the algorithm provided to obtain optimal profit. And we also obtain managerial implications from numerical examples to substantiate our model. The results show that there is an improvement in total profit from complete backlogging rather than the items being partially backlogged.

  11. Existence,uniqueness and ergodicity of Markov branching processes with immigration and instantaneous resurrection

    Institute of Scientific and Technical Information of China (English)

    LI JunPing; CHEN AnYue

    2008-01-01

    We consider a modified Markov branching process incorporating with both stateindependent immigration and instantaneous resurrection. The existence criterion of the process is firstly considered. We prove that if the sum of the resurrection rates is finite, then there does not exist any process. An existence criterion is then established when the sum of the resurrection rates is infinite.Some equivalent criteria, possessing the advantage of being easily checked, are obtained for the latter case. The uniqueness criterion for such process is also investigated. We prove that although there exist infinitely many of them, there always exists a unique honest process for a given q-matrix. This unique honest process is then constructed. The ergodicity property of this honest process is analysed in detail.We prove that this honest process is always ergodic and the explicit expression for the equilibrium distribution is established.

  12. Instantaneous high-resolution focus tracking and a vibrometery system using parallel phase shift interferometry

    Science.gov (United States)

    Ney, Michael; Safrani, Avner; Abdulhlaim, Ibrahim

    2016-09-01

    High resolution fast focus tracking and vibrometery system based on parallel phase shift polarization interferometry using three detectors is presented. The basic design and algorithm are described, followed by an experimental demonstration showing sub nm resolution of different controlled motion profiles instantaneously monitored at a feedback rate of 100 kHz. The fact that the method does not rely on active optical components, potentially allows extremely high vibration rates to be measured; limited only by the detector bandwidth and sampling rate. In addition, the relatively simple design relies only on standard optical equipment, combined with the simple algorithm, makes the task of setting up a high performance vibrometry system cheap and readily available.

  13. Direct Instantaneous Torque Control of 4 Phase 8/6 Switched Reluctance Motor

    Directory of Open Access Journals (Sweden)

    Srinivas Pratapgiri

    2011-10-01

    Full Text Available The applications of Switched Reluctance Motor Drives has increased  in the recent past because of advantages like simple structure, no rotor winding, high torque to weight ratio, adaptability to harsh environments like coal mining etc. But the main disadvantage is that torque ripple is high because of the double saliency. This paper presents a high dynamic control technique called Direct Instantaneous Torque Control (DITC where in the torque is maintained within a hysteresis band by changing the switching states of the phases between 1, 0 or -1.Thus torque ripple minimization is an inherent property of DITC. DITC based SRM drive is simulated in MATLAB/SIMULINK environment and results are discussed elaborately

  14. Effect of Coating on Instantaneous Interracial Heat Transfer During Near-Rapid Solidification

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; YU Yan; FANG Yuan; LI Jian-guo

    2011-01-01

    For many rapid or near-rapid solidification processes, the interracial heat transfer between the melt and the substrate is a key issue on the cooling and solidification rate of castings. For the purpose of controlling and adjusting of the interfacial thermal resistance, the effects of C/BN, Zn and organic coatings on the instantaneous interracial heat flux and the solidified structure of AISI304 stainless steel solidification on copper substrate have been investiga- ted by using an experimental simulator. The results show that C/BN coatings can improve the uniformity of heat flux and solidified structure; Zn coating can increase the heat flux and solidification rate in the growth stage of the solidified shell; organic coating will decrease the heat flux and the solidification rate and make re-melted structure on the surface of the solidified shell.

  15. Orthogonality breaking sensing model based on the instantaneous Stokes vector and the Mueller calculus

    CERN Document Server

    Ortega-Quijano, Noé; Roche, Muriel; Parnet, François; Alouini, Mehdi

    2015-01-01

    Polarimetric sensing by orthogonality breaking has been recently proposed as an alternative technique for performing direct and fast polarimetric measurements using a specific dual-frequency dual-polarization (DFDP) source. Based on the instantaneous Stokes-Mueller formalism to describe the high-frequency evolution of the DFDP beam intensity, we thoroughly analyze the interaction of such a beam with birefringent, dichroic and depolarizing samples. This allows us to confirm that orthogonality breaking is produced by the sample diattenuation, whereas this technique is immune to both birefringence and diagonal depolarization. We further analyze the robustness of this technique when polarimetric sensing is performed through a birefringent waveguide, and the optimal DFDP source configuration for fiber-based endoscopic measurements is subsequently identified. Finally, we consider a stochastic depolarization model based on an ensemble of random linear diattenuators, which makes it possible to understand the progress...

  16. INSTANTANEOUS STARBURST OF THE MASSIVE CLUSTERS WESTERLUND 1 AND NGC 3603 YC

    Energy Technology Data Exchange (ETDEWEB)

    Kudryavtseva, Natalia; Brandner, Wolfgang; Gennaro, Mario; Rochau, Boyke; Henning, Thomas [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg (Germany); Stolte, Andrea [Argelander Institut fuer Astronomie, Auf dem Huegel 71, 53121 Bonn (Germany); Andersen, Morten; Da Rio, Nicola [European Space Agency, Space Science Department, Keplerlaan 1, 2200 AG Noordwijk (Netherlands); Tognelli, Emanuele [Department of Physics, University of Pisa, Largo Bruno Pontecorvo 3, 56127 Pisa (Italy); Hogg, David [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, Room 424, New York, NY 10003 (United States); Clark, Simon [Department of Physics and Astronomy, The Open University, Milton Keynes MK7 6AA (United Kingdom); Waters, Rens [Sterrenkundig Instituut Anton Pannekoek, University of Amsterdam, Science Park 904, 1098 Amsterdam (Netherlands)

    2012-05-10

    We present a new method to determine the age spread of resolved stellar populations in a starburst cluster. The method relies on a two-step process. In the first step, kinematic members of the cluster are identified based on multi-epoch astrometric monitoring. In the second step, a Bayesian analysis is carried out, comparing the observed photometric sequence of cluster members with sets of theoretical isochrones. When applying this methodology to optical and near-infrared high angular resolution Hubble Space Telescope (HST) and adaptive optics observations of the {approx}5 Myr old starburst cluster Westerlund 1 and {approx}2 Myr old starburst cluster NGC 3603 YC, we derive upper limits for the age spreads of 0.4 and 0.1 Myr, respectively. The results strongly suggest that star formation in these starburst clusters happened almost instantaneously.

  17. All-optically induced ultrafast photocurrents: Beyond the instantaneous coherent response

    CERN Document Server

    Priyadarshi, Shekhar; Bieler, Mark

    2012-01-01

    It is demonstrated that the non-instantaneous response of the optically induced coherent polarization tremendously influences the real-space shift of electronic charges in semiconductors. The possibility to coherently control this real-space shift with temporally non-overlapping excitation pulses allows for the observation of a new type of shift current, which only exists for certain polarization-shaped excitation pulses and vanishes in the continuous-wave limit. In contrast to previously studied shift currents, the new current requires a phase mismatch between two orthogonal transition dipole moments and leads, within a nonlinear second-order description, to a tensor which is antisymmetric with respect to the order of the two exciting electric field amplitudes. These observations, which can even be made at room temperature and are expected to occur in a variety of semiconductor crystal classes, contribute to a better understanding of light-matter interaction involving degenerate bands. Thus, they are expecte...

  18. Retrograde diurnal motion of the instantaneous rotation axis observed by a large ring laser gyroscope

    Science.gov (United States)

    Tian, W.

    2016-07-01

    Ring laser gyroscope technique directly senses the Earth's instantaneous rotation pole (IRP), whose polar motion contains strong retrograde diurnal components induced by external torques due to the gravitational attraction of the Moon and Sun. The first direct measurement of this retrograde diurnal motion with three large ring lasers was reported by Schreiber et al. (J Geophys Res 109(B18):B06405, 2004). Since then many technical improvements led to a significant increase in precision and stability of ring laser gyroscopes; however, precise determination of amplitude and phase at main partial waves has not been given in the literature. In this paper, I will report on determination of the retrograde diurnal motion of the IRP at main partial waves (Oo_1, J_1, K_1, M_1, O_1, Q_1 ) by the ring laser "G", located in Wettzell, Germany, which is the most stable one amongst the currently running large ring laser gyroscopes.

  19. Optimal Production Planning for Manufacturing Systems with Instantaneous Stock-Dependent Demand and Imperfect Yields

    Directory of Open Access Journals (Sweden)

    Longfei He

    2015-01-01

    Full Text Available We consider an EPL model like manufacturing system in presence of production imperfectness and stock-demand dependence simultaneously. During the production process, the system can evolve from in-control state into out-of-control state at any random time, after which the defective items will be generated likely causing quantity loss. Meanwhile, the market demand rate is instantaneously dependent on the timely holding inventory. The manufacturer has to determine his production run length and cycle time by taking into account possible imperfect production, stock-dependent demand, and inventory holding capacity bound. We empolder a model to capture this problem and develop computational algorithm to solve it. We further conduct numerical studies to validate our model and solving method. Sensitivity analyses are reported to show the effect of parameters on the system performance.

  20. Toothbrush probe for instantaneous measurement of radial profile in tokamak boundary plasma

    Energy Technology Data Exchange (ETDEWEB)

    Uehara, Kazuya; Sengoku, Seio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Amemiya, Hiroshi

    1997-04-01

    A new probe for the instantaneous measurement of radial profiles of the boundary scrape-off layer (SOL) plasma has been developed in a tokamak. Five asymmetric double-probe chips are aligned in parallel to a strong magnetic field in the boundary plasma in a tokamak. This probe is named the `toothbrush probe` and can measure the ion temperature as well as the electron temperature and the plasma density in the SOL plasma within only one tokamak plasma shot. First, only one asymmetric probe is mounted on the divertor plate and it is tried to determine the ion temperature. Then, a manufactured toothbrush probe is mounted in the SOL plasma and the radial plasma profiles are simultaneously obtained. Data on the e-folding length of the plasma profile obtained by the toothbrush probe can determine the information on the transport properties such as the diffusion coefficient and the thermal conductivity of electrons and ions. (author)