WorldWideScience

Sample records for shock index project

  1. Prediction of massive bleeding. Shock index and modified shock index.

    Terceros-Almanza, L J; García-Fuentes, C; Bermejo-Aznárez, S; Prieto-Del Portillo, I J; Mudarra-Reche, C; Sáez-de la Fuente, I; Chico-Fernández, M

    2017-12-01

    To determine the predictive value of the Shock Index and Modified Shock Index in patients with massive bleeding due to severe trauma. Retrospective cohort. Severe trauma patient's initial attention at the intensive care unit of a tertiary hospital. Patients older than 14 years that were admitted to the hospital with severe trauma (Injury Severity Score >15) form January 2014 to December 2015. We studied the sensitivity (Se), specificity (Sp), positive and negative predictive value (PV+ and PV-), positive and negative likelihood ratio (LR+ and LR-), ROC curves (Receiver Operating Characteristics) and the area under the same (AUROC) for prediction of massive hemorrhage. 287 patients were included, 76.31% (219) were male, mean age was 43,36 (±17.71) years and ISS was 26 (interquartile range [IQR]: 21-34). The overall frequency of massive bleeding was 8.71% (25). For Shock Index: AUROC was 0.89 (95% confidence intervals [CI] 0.84 to 0.94), with an optimal cutoff at 1.11, Se was 91.3% (95% CI: 73.2 to 97.58) and Sp was 79.69% (95% CI: 74.34 to 84.16). For the Modified Shock Index: AUROC was 0.90 (95% CI: 0.86 to 0.95), with an optimal cutoff at 1.46, Se was 95.65% (95% CI: 79.01 to 99.23) and Sp was 75.78% (95% CI: 70.18 to 80.62). Shock Index and Modified Shock Index are good predictors of massive bleeding and could be easily incorporated to the initial workup of patients with severe trauma. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  2. Prediction of Massive Transfusion in Trauma Patients with Shock Index, Modified Shock Index, and Age Shock Index

    Cheng-Shyuan Rau

    2016-07-01

    Full Text Available Objectives: The shock index (SI and its derivations, the modified shock index (MSI and the age shock index (Age SI, have been used to identify trauma patients with unstable hemodynamic status. The aim of this study was to evaluate their use in predicting the requirement for massive transfusion (MT in trauma patients upon arrival at the hospital. Participants: A patient receiving transfusion of 10 or more units of packed red blood cells or whole blood within 24 h of arrival at the emergency department was defined as having received MT. Detailed data of 2490 patients hospitalized for trauma between 1 January 2009, and 31 December 2014, who had received blood transfusion within 24 h of arrival at the emergency department, were retrieved from the Trauma Registry System of a level I regional trauma center. These included 99 patients who received MT and 2391 patients who did not. Patients with incomplete registration data were excluded from the study. The two-sided Fisher exact test or Pearson chi-square test were used to compare categorical data. The unpaired Student t-test was used to analyze normally distributed continuous data, and the Mann-Whitney U-test was used to compare non-normally distributed data. Parameters including systolic blood pressure (SBP, heart rate (HR, hemoglobin level (Hb, base deficit (BD, SI, MSI, and Age SI that could provide cut-off points for predicting the patients’ probability of receiving MT were identified by the development of specific receiver operating characteristic (ROC curves. High accuracy was defined as an area under the curve (AUC of more than 0.9, moderate accuracy was defined as an AUC between 0.9 and 0.7, and low accuracy was defined as an AUC less than 0.7. Results: In addition to a significantly higher Injury Severity Score (ISS and worse outcome, the patients requiring MT presented with a significantly higher HR and lower SBP, Hb, and BD, as well as significantly increased SI, MSI, and Age SI. Among

  3. Is shock index associated with outcome in children with sepsis/septic shock?*.

    Yasaka, Yuki; Khemani, Robinder G; Markovitz, Barry P

    2013-10-01

    To investigate the association between PICU shock index (the ratio of heart rate to systolic blood pressure) and PICU mortality in children with sepsis/septic shock. To explore cutoff values for shock index for ICU mortality, how change in shock index over the first 6 hours of ICU admission is associated with outcome, and how the use of vasoactive therapy may affect shock index and its association with outcome. Retrospective cohort. Single-center tertiary PICU. Five hundred forty-four children with the diagnosis of sepsis/septic shock. None. From January 2003 to December 2009, 544 children met International Pediatric Sepsis Consensus Conference of 2005 criteria for sepsis/septic shock. Overall mortality was 23.7%. Among all patients, hourly shock index was associated with mortality: odds ratio of ICU mortality at 0 hour, 1.08, 95% CI (1.04-1.12); odds ratio at 1 hour, 1.09 (1.04-1.13); odds ratio at 2 hours, 1.09 (1.05-1.13); and odds ratio at 6 hours, 1.11 (1.06-1.15). When stratified by age, early shock index was associated with mortality only in children 1-3 and more than or equal to 12 years old. Area under the receiver operating characteristic curve in age 1-3 and more than or equal to 12 years old for shock index at admission was 0.69 (95% CI, 0.58-0.80) and 0.62 (95% CI, 0.52-0.72) respectively, indicating a fair predictive marker. Although higher shock index was associated with increased risk of mortality, there was no particular cutoff value with adequate positive or negative likelihood ratios to identify mortality in any age group of children. The improvement of shock index in the first 6 hours of ICU admission was not associated with outcome when analyzed in all patients. However, among patients whose shock index were above the 50th percentile at ICU admission for each age group, improvement of shock index was associated with lower ICU mortality in children between 1-3 and more than or equal to 12 years old (p = 0.02 and p = 0.03, respectively). When

  4. Shock Index More Sensitive Than Cardiogenic Shock in ST-Elevation Myocardial Infarction Treated by Primary Percutaneous Coronary Intervention

    Hemradj, V.V.; Ottervanger, J.P.; Boer, M.J. de; Suryapranata, H.

    2017-01-01

    BACKGROUND: Cardiogenic shock (CS) is a strong predictor of mortality in patients with ST-elevation myocardial infarction (STEMI), but there is evidence that shock index (SI), taking into account both blood pressure and heart rate, is a more sensitive and powerful predictor. We investigated the

  5. Extremes of shock index predicts death in trauma patients

    Stephen R Odom

    2016-01-01

    Full Text Available Context: We noted a bimodal relationship between mortality and shock index (SI, the ratio of heart rate to systolic blood pressure. Aims: To determine if extremes of SI can predict mortality in trauma patients. Settings and Designs: Retrospective evaluation of adult trauma patients at a tertiary care center from 2000 to 2012 in the United States. Materials and Methods: We examined the SI in trauma patients and determined the adjusted mortality for patients with and without head injuries. Statistical Analysis Used: Descriptive statistics and multivariable logistic regression. Results: SI values demonstrated a U-shaped relationship with mortality. Compared with patients with a SI between 0.5 and 0.7, patients with a SI of 1.3 had an odds ratio of death of 3.1. (95% CI 1.6–5.9. Elevated SI is associated with increased mortality in patients with isolated torso injuries, and is associated with death at both low and high values in patients with head injury. Conclusion: Our data indicate a bimodal relationship between SI and mortality in head injured patients that persists after correction for various co-factors. The distribution of mortality is different between head injured patients and patients without head injuries. Elevated SI predicts death in all trauma patients, but low SI values only predict death in head injured patients.

  6. Central venous pressure and shock index predict lack of hemodynamic response to volume expansion in septic shock: a prospective, observational study.

    Lanspa, Michael J; Brown, Samuel M; Hirshberg, Eliotte L; Jones, Jason P; Grissom, Colin K

    2012-12-01

    Volume expansion is a common therapeutic intervention in septic shock, although patient response to the intervention is difficult to predict. Central venous pressure (CVP) and shock index have been used independently to guide volume expansion, although their use is questionable. We hypothesize that a combination of these measurements will be useful. In a prospective, observational study, patients with early septic shock received 10-mL/kg volume expansion at their treating physician's discretion after brief initial resuscitation in the emergency department. Central venous pressure and shock index were measured before volume expansion interventions. Cardiac index was measured immediately before and after the volume expansion using transthoracic echocardiography. Hemodynamic response was defined as an increase in a cardiac index of 15% or greater. Thirty-four volume expansions were observed in 25 patients. A CVP of 8 mm Hg or greater and a shock index of 1 beat min(-1) mm Hg(-1) or less individually had a good negative predictive value (83% and 88%, respectively). Of 34 volume expansions, the combination of both a high CVP and a low shock index was extremely unlikely to elicit hemodynamic response (negative predictive value, 93%; P = .02). Volume expansion in patients with early septic shock with a CVP of 8 mm Hg or greater and a shock index of 1 beat min(-1) mm Hg(-1) or less is unlikely to lead to an increase in cardiac index. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Shock index as a mortality predictor in patients with acute polytrauma

    Kevin Fernando Montoya; Jos Daniel Charry; Juan Sebastin Calle-Toro; Luis Ramiro Niez; Gustavo Poveda

    2015-01-01

    Objective: To evaluate whether the shock index (SI), given by the formula SI = heart rate /systolic blood pressure (HR / SBP), is useful for predicting mortality at 24 h in trauma patients admitted to the emergency department of a university hospital in Colombia. Methods: A database of trauma patients admitted between January 2013 and December 2013 was constructed; the result according to the shock index was determined, generating a dichotomous variable with two groups: Group A (SI 0.9). Univariate analysis was performed. Results: A total of 666 patients were analyzed, 83.3% (555) had SI 0.9. The mean age for Groups A and B was 32.4 and 35.4 respectively. The average injury severity score for both groups was 9.6 and 17.6 respectively. Mortality at 24 h after injury for both groups was 3.1% (P = 0.032) and 59.5% (P = 0.027) respectively. Conclusions: An initial shock index greater than 0.9 implies a worse prognosis 24 h after injury. The shock index predicts mortality in multiple trauma patients in the emergency department, and is also a quick and applicable in all hospital.

  8. Refractive index of r-cut sapphire under shock pressure range 5 to 65 GPa

    Cao, Xiuxia; Li, Jiabo; Li, Jun; Li, Xuhai; Xu, Liang; Wang, Yuan; Zhu, Wenjun; Meng, Chuanmin; Zhou, Xianming

    2014-01-01

    High-pressure refractive index of optical window materials not only can provide information on electronic polarizability and band-gap structure, but also is important for velocity correction in particle-velocity measurement with laser interferometers. In this work, the refractive index of r-cut sapphire window at 1550 nm wavelength was measured under shock pressures of 5–65 GPa. The refractive index (n) decreases linearly with increasing shock density (ρ) for shock stress above the Hugoniot elastic limit (HEL): n = 2.0485 (± 0.0197) − 0.0729 (± 0.0043)ρ, while n remains nearly a constant for elastic shocks. This behavior is attributed to the transition from elastic (below HEL) to heterogeneous plastic deformation (above HEL). Based on the obtained refractive index-density relationship, polarizability of the shocked sapphire was also obtained

  9. Complex Evaluation Oxygen Status and Lipid Metabolism Indexes in Newborns with Perinatal Hypoxia and Hypovolemic Shock

    Svetlana A. Perepelitsa

    2017-01-01

    Full Text Available Aim. To asses of metabolism, lipid metabolism and oxygen status parameters in newborns with perinatal hypoxia.Materials and Methods. 53 newborn babies born with signs of severe hypoxia and low Apgar scoring equal to 2 at the 1st minute of life were enrolled in the study. Newborns were divided into 2 groups depending on the presence of the clinical presentation of shock: Group 1 «Shock» and Group 2 «Acute intranatal hypoxia» (AIH. All newborns underwent testing for blood gas and acid-base balance, lactate level. Cholesterol and triglyceride levels in the central venous blood were also tested immediately after the birth and on the 5th day of life. Mechanical ventilation mode and parameters were registered. The mean airway pressure (MAP and the oxygen saturation index (OSI were calculated.Results. Severe decompensated metabolic lactic acidosis was diagnosed in a «Shock» group newborns at birth, thus indicating severe perinatal hypoxia which had triggered the development of shock. As for the «AIH» group newborns, they had hyperlactatemia alone. The most severe hypoxemia at birth was diagnosed in newborns of the «Shock» group; the OSI value in these infants was significantly higher than that in «AIH» infants (P<0.01. Despite the treatment and mechanical ventilation, during the posthypoxic period, newborns from the «Shock» group were characterized by increased OSI values over 12 hours after birth. Significantly high levels of OSI persisted for 48 hours after the delivery. Severe hypotriglyceridemia and hypocholesterolemia were found in both group newborns.Conclusion. The study demonstrated that there was intranatal complex metabolism impairment in the case of perinatal hypoxia; at birth, it manifested by metabolic acidosis of various degrees of severity and imbalance of triglycerides and cholesterol levels. The longer and more severe hypoxia is, the more severe acid-base balance and blood lactate level impairment at birth become

  10. Accuracy of shock index versus ABC score to predict need for massive transfusion in trauma patients.

    Schroll, Rebecca; Swift, David; Tatum, Danielle; Couch, Stuart; Heaney, Jiselle B; Llado-Farrulla, Monica; Zucker, Shana; Gill, Frances; Brown, Griffin; Buffin, Nicholas; Duchesne, Juan

    2018-01-01

    Various scoring systems have been developed to predict need for massive transfusion in traumatically injured patients. Assessments of Blood Consumption (ABC) score and Shock Index (SI) have been shown to be reliable predictors for Massive Transfusion Protocol (MTP) activation. However, no study has directly compared these two scoring systems to determine which is a better predictor for MTP activation. The primary objective was to determine whether ABC or SI better predicted the need for MTP in adult trauma patients with severe hemorrhage. This was a retrospective cohort study which included all injured patients who were trauma activations between January 1, 2009 and December 31, 2013 at an urban Level I trauma center. Patients ABC and SI were calculated for each patient. MTP was defined as need for >10 units PRBC transfusion within 24h of emergency department arrival. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) were used to evaluate scoring systems' ability to predict effective MTP utilization. A total of 645 patients had complete data for analysis. Shock Index ≥1 had sensitivity of 67.7% (95% CI 49.5%-82.6%) and specificity of 81.3% (95% CI 78.0%-84.3%) for predicting MTP, and ABC score ≥2 had sensitivity of 47.0% (95% CI 29.8%-64.9%) and specificity of 89.8% (95% CI 87.2%-92.1%). AUROC analyses showed SI to be the strongest predictor followed by ABC score with AUROC values of 0.83 and 0.74, respectively. SI had a significantly greater sensitivity (P=0.035), but a significantly weaker specificity (PABC score. ABC score and Shock Index can both be used to predict need for massive transfusion in trauma patients, however SI is more sensitive and requires less technical skill than ABC score. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Prognostic value of brachioradialis muscle oxygen saturation index and vascular occlusion test in septic shock patients.

    Marín-Corral, J; Claverias, L; Bodí, M; Pascual, S; Dubin, A; Gea, J; Rodriguez, A

    2016-05-01

    To compare rSO2 (muscle oxygen saturation index) static and dynamic variables obtained by NIRS (Near Infrared Spectroscopy) in brachioradialis muscle of septic shock patients and its prognostic implications. Prospective and observational study. Intensive care unit. Septic shock patients and healthy volunteers. The probe of a NIRS device (INVOS 5100) was placed on the brachioradialis muscle during a vascular occlusion test (VOT). Baseline, minimum and maximum rSO2 values, deoxygenation rate (DeOx), reoxygenation slope (ReOx) and delta value. Septic shock patients (n=35) had lower baseline rSO2 (63.8±12.2 vs. 69.3±3.3%, p<0.05), slower DeOx (-0.54±0.31 vs. -0.91±0.35%/s, p=0.001), slower ReOx (2.67±2.17 vs. 9.46±3.5%/s, p<0.001) and lower delta (3.25±5.71 vs. 15.1±3.9%, p<0.001) when compared to healthy subjects (n=20). Among septic shock patients, non-survivors showed lower baseline rSO2 (57.0±9.6 vs. 69.8±11.3%, p=0.001), lower minimum rSO2 (36.0±12.8 vs. 51.3±14.8%, p<0.01) and lower maximum rSO2 values (60.6±10.6 vs. 73.3±11.2%, p<0.01). Baseline rSO2 was a good mortality predictor (AUC 0.79; 95%CI: 0.63-0.94, p<0.01). Dynamic parameters obtained with VOT did not improve the results. Septic shock patients present an important alteration of microcirculation that can be evaluated by NIRS with prognostic implications. Monitoring microvascular reactivity in the brachioradialis muscle using VOT with our device does not seem to improve the prognostic value of baseline rSO2. Copyright © 2015 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

  12. Determining the refractive index of shocked [100] lithium fluoride to the limit of transmissibility

    Rigg, P. A.; Scharff, R. J.; Hixson, R. S.; Knudson, M. D.

    2014-01-01

    Lithium fluoride (LiF) is a common window material used in shock- and ramp-compression experiments because it displays a host of positive attributes in these applications. Most commonly, it is used to maintain stress at an interface and velocimetry techniques are used to record the particle velocity at that interface. In this application, LiF remains transparent to stresses up to 200 GPa. In this stress range, LiF has an elastic-plastic response with a very low (<0.5 GPa) elastic precursor and exhibits no known solid-solid phase transformations. However, because the density dependence of the refractive index of LiF does not follow the Gladstone-Dale relation, the measured particle velocity at this interface is not the true particle velocity and must be corrected. For that reason, the measured velocity is often referred to as the apparent velocity in these types of experiments. In this article, we describe a series of shock-compression experiments that have been performed to determine the refractive index of LiF at the two most commonly used wavelengths (532 nm and 1550 nm) between 35 and 200 GPa to high precision. A modified form of the Gladstone-Dale relation was found to work best to fit the determined values of refractive index. In addition, we provide a direct relationship between the apparent and true particle velocity to correct experimentally obtained wave profiles by others using these velocimetry techniques.

  13. A relaxation-projection method for compressible flows. Part II: Artificial heat exchanges for multiphase shocks

    Petitpas, Fabien; Franquet, Erwin; Saurel, Richard; Le Metayer, Olivier

    2007-01-01

    The relaxation-projection method developed in Saurel et al. [R. Saurel, E. Franquet, E. Daniel, O. Le Metayer, A relaxation-projection method for compressible flows. Part I: The numerical equation of state for the Euler equations, J. Comput. Phys. (2007) 822-845] is extended to the non-conservative hyperbolic multiphase flow model of Kapila et al. [A.K. Kapila, Menikoff, J.B. Bdzil, S.F. Son, D.S. Stewart, Two-phase modeling of deflagration to detonation transition in granular materials: reduced equations, Physics of Fluids 13(10) (2001) 3002-3024]. This model has the ability to treat multi-temperatures mixtures evolving with a single pressure and velocity and is particularly interesting for the computation of interface problems with compressible materials as well as wave propagation in heterogeneous mixtures. The non-conservative character of this model poses however computational challenges in the presence of shocks. The first issue is related to the Riemann problem resolution that necessitates shock jump conditions. Thanks to the Rankine-Hugoniot relations proposed and validated in Saurel et al. [R. Saurel, O. Le Metayer, J. Massoni, S. Gavrilyuk, Shock jump conditions for multiphase mixtures with stiff mechanical relaxation, Shock Waves 16 (3) (2007) 209-232] exact and approximate 2-shocks Riemann solvers are derived. However, the Riemann solver is only a part of a numerical scheme and non-conservative variables pose extra difficulties for the projection or cell average of the solution. It is shown that conventional Godunov schemes are unable to converge to the exact solution for strong multiphase shocks. This is due to the incorrect partition of the energies or entropies in the cell averaged mixture. To circumvent this difficulty a specific Lagrangian scheme is developed. The correct partition of the energies is achieved by using an artificial heat exchange in the shock layer. With the help of an asymptotic analysis this heat exchange takes a similar form as

  14. A relaxation-projection method for compressible flows. Part II: Artificial heat exchanges for multiphase shocks

    Petitpas, Fabien; Franquet, Erwin; Saurel, Richard; Le Metayer, Olivier

    2007-08-01

    The relaxation-projection method developed in Saurel et al. [R. Saurel, E. Franquet, E. Daniel, O. Le Metayer, A relaxation-projection method for compressible flows. Part I: The numerical equation of state for the Euler equations, J. Comput. Phys. (2007) 822-845] is extended to the non-conservative hyperbolic multiphase flow model of Kapila et al. [A.K. Kapila, Menikoff, J.B. Bdzil, S.F. Son, D.S. Stewart, Two-phase modeling of deflagration to detonation transition in granular materials: reduced equations, Physics of Fluids 13(10) (2001) 3002-3024]. This model has the ability to treat multi-temperatures mixtures evolving with a single pressure and velocity and is particularly interesting for the computation of interface problems with compressible materials as well as wave propagation in heterogeneous mixtures. The non-conservative character of this model poses however computational challenges in the presence of shocks. The first issue is related to the Riemann problem resolution that necessitates shock jump conditions. Thanks to the Rankine-Hugoniot relations proposed and validated in Saurel et al. [R. Saurel, O. Le Metayer, J. Massoni, S. Gavrilyuk, Shock jump conditions for multiphase mixtures with stiff mechanical relaxation, Shock Waves 16 (3) (2007) 209-232] exact and approximate 2-shocks Riemann solvers are derived. However, the Riemann solver is only a part of a numerical scheme and non-conservative variables pose extra difficulties for the projection or cell average of the solution. It is shown that conventional Godunov schemes are unable to converge to the exact solution for strong multiphase shocks. This is due to the incorrect partition of the energies or entropies in the cell averaged mixture. To circumvent this difficulty a specific Lagrangian scheme is developed. The correct partition of the energies is achieved by using an artificial heat exchange in the shock layer. With the help of an asymptotic analysis this heat exchange takes a similar form as

  15. The Milky Way Project: A Citizen Science Catalog of Infrared Bow Shock Nebulae

    Dixon, Don; Jayasinghe, Tharindu; Povich, Matthew S.

    2017-01-01

    We present preliminary results from the first citizen-science search for infrared stellar-wind bow shock candidates. This search uses the Milky Way project, hosted by the Zooniverse, an online platform with over 1 million volunteer citizen scientists. Milky Way Project volunteers examine 77,000 randomly-distributed Spitzer image cutouts at varying zoom levels. Volunteers mark the infrared arc of potential bow shock candidates as well as the star likely driving the nebula. We produce lists of candidates from bow shocks flagged by multiple volunteers, which after merging and final visual review form the basis for our catalog. Comparing our new catalog to a recently-published catalog of 709 infrared bow shock candidates identified by a small team of (primarily undergraduate) researchers will allow us to assess the effectiveness of citizen science for this type of search and should yield a more complete catalog. Planned studies using these large catalogs will improve constraints on the mass-loss rates for the massive stars that create these bow shock nebulae. Mass-loss rates are highly uncertain but are a critical component of evolutionary models for massive stars. This work is supported by the National Science Foundation under grants CAREER-1454334, AST-1411851 (RUI) and AST-1412845.

  16. Shock Index Correlates with Extravasation on Angiographs of Gastrointestinal Hemorrhage: A Logistics Regression Analysis

    Nakasone, Yutaka; Ikeda, Osamu; Yamashita, Yasuyuki; Kudoh, Kouichi; Shigematsu, Yoshinori; Harada, Kazunori

    2007-01-01

    We applied multivariate analysis to the clinical findings in patients with acute gastrointestinal (GI) hemorrhage and compared the relationship between these findings and angiographic evidence of extravasation. Our study population consisted of 46 patients with acute GI bleeding. They were divided into two groups. In group 1 we retrospectively analyzed 41 angiograms obtained in 29 patients (age range, 25-91 years; average, 71 years). Their clinical findings including the shock index (SI), diastolic blood pressure, hemoglobin, platelet counts, and age, which were quantitatively analyzed. In group 2, consisting of 17 patients (age range, 21-78 years; average, 60 years), we prospectively applied statistical analysis by a logistics regression model to their clinical findings and then assessed 21 angiograms obtained in these patients to determine whether our model was useful for predicting the presence of angiographic evidence of extravasation. On 18 of 41 (43.9%) angiograms in group 1 there was evidence of extravasation; in 3 patients it was demonstrated only by selective angiography. Factors significantly associated with angiographic visualization of extravasation were the SI and patient age. For differentiation between cases with and cases without angiographic evidence of extravasation, the maximum cutoff point was between 0.51 and 0.0.53. Of the 21 angiograms obtained in group 2, 13 (61.9%) showed evidence of extravasation; in 1 patient it was demonstrated only on selective angiograms. We found that in 90% of the cases, the prospective application of our model correctly predicted the angiographically confirmed presence or absence of extravasation. We conclude that in patients with GI hemorrhage, angiographic visualization of extravasation is associated with the pre-embolization SI. Patients with a high SI value should undergo study to facilitate optimal treatment planning

  17. Climate Risk and Production Shocks: Using Index Insurance to Link Climate Science to Policy for Sustainable Development

    McCarney, G. R.; Osgood, D. E.

    2011-12-01

    Smallholder farmers in developing countries are often severely impacted by droughts and other climate related events. However, agricultural insurance programs are largely unavailable in lower-income countries because of limitations in traditional loss-based indemnity insurance. As a result, it is often the case that farmers who are the most vulnerable to climate shocks lack access to the insurance tools that could help to reduce their production risk. Index insurance, a recent financial innovation, has the potential to increase access to insurance for smallholder farmers (Barrett et al. 2007). Index insurance allows farmers to insure their production risk based on a weather index (such as total seasonal rainfall) rather than on crop yields. The use of a weather index addresses many of the perverse incentive problems found in traditional crop insurance, and greatly reduces the costs of insuring smallholder farmers. The trade-off in index insurance, however, is limited accuracy in calibrating payouts to actual losses, a phenomenon commonly known as basis risk. While index insurance has promise as a risk-smoothing instrument, many argue it has greater promise as a mechanism for improving access to credit for smallholder farmers in developing countries (e.g. Barnett, Barrett & Skees 2008). In these areas, farmers are often fully exposed to climate shocks, which greatly affect their willingness to borrow. By smoothing the uncertainty in climate shocks, insurance may allow farmers to take credit for productive risks. There has been much discussion as to the optimal strategy for combining index insurance with credit, specifically if the financial institutions or the individual farmers themselves should hold the insurance policy. Many existing insurance implementations insure the farmer directly. However, since a weather index is a proxy for yield loss based on regional data, there is basis risk due to uninsured idiosyncratic differences between farmers. As a response to

  18. International shock-wave database project : report of the requirements workshop.

    Aidun, John Bahram (Institute of Problems of chemical Physics of Russian Academy of Sciences); Lomonosov, Igor V. (Institute of Problems of chemical Physics of Russian Academy of Sciences); Levashov, Pavel R. (Joint Institute for High Temperatures of Russian Academy of Sciences)

    2012-03-01

    We report on the requirements workshop for a new project, the International Shock-Wave database (ISWdb), which was held October 31 - November 2, 2011, at GSI, Darmstadt, Germany. Participants considered the idea of this database, its structure, technical requirements, content, and principles of operation. This report presents the consensus conclusions from the workshop, key discussion points, and the goals and plan for near-term and intermediate-term development of the ISWdb. The main points of consensus from the workshop were: (1) This international database is of interest and of practical use for the shock-wave and high pressure physics communities; (2) Intermediate state information and off-Hugoniot information is important and should be included in ISWdb; (3) Other relevant high pressure and auxiliary data should be included to the database, in the future; (4) Information on the ISWdb needs to be communicated, broadly, to the research community; and (5) Operating structure will consist of an Advisory Board, subject-matter expert Moderators to vet submitted data, and the database Project Team. This brief report is intended to inform the shock-wave research community and interested funding agencies about the project, as its success, ultimately, depends on both of these groups finding sufficient value in the database to use it, contribute to it, and support it.

  19. Type II successful supernovae, the anatomy of shocks: neutrino emission and the adiabatic index

    Kahana, S.; Baron, E.; Cooperstein, J.

    1983-01-01

    Hydrodynamic calculations of stellar collapse in Type II Supernova are described using a variable stiffness and compressibility for the nuclear equation of state at high density. Initial models employing a relatively small mass core with low central entropy are necessary to achieve viable shocks; near success the models are sensitive to both neutrino emission and the high density equation of state. The treatment of neutrino production and transport is sketched and recent results reported

  20. Interferometric windows characterization up to 450 K for shock wave experiments: Hugoniot curves and refractive index

    Godefroit J.-L.

    2012-08-01

    Full Text Available Conventional shock wave experiments need interferometric windows in order to determine the equation of state of a large variety of metals. Lithium fluoride (LiF and sapphire are extensively used for that purpose because their optical transparencies enable the optical diagnostics at interfaces under a given range of shock pressure. In order to simulate and analyse the experiments it is necessary to gather a correct knowledge of the optical and mechanical properties of these windows. Therefore, our window supplies are systematically characterized and an experimental campaign under shock loading is conducted. Our preliminary work on LiF windows at 532 nm is in good agreement with literature data at room temperature and the new characterization at 450 K enables a better interpretation of our preheated target experiments. It confirms the predominant effect of density on optical properties under pressure and temperature. The present work demonstrates that the initial density determination is a key point and that the uncertainties need to be improved. For that purpose, complementary experiments are conducted on LiF windows with simplified target designs and enriched diagnostics, coupling VISAR (532 nm and PdV (1550 nm diagnostics. Furthermore, a similar campaign is conducted on sapphire windows with symmetric impact configuration.

  1. What Climate Sensitivity Index Is Most Useful for Projections?

    Grose, Michael R.; Gregory, Jonathan; Colman, Robert; Andrews, Timothy

    2018-02-01

    Transient climate response (TCR), transient response at 140 years (T140), and equilibrium climate sensitivity (ECS) indices are intended as benchmarks for comparing the magnitude of climate response projected by climate models. It is generally assumed that TCR or T140 would explain more variability between models than ECS for temperature change over the 21st century, since this timescale is the realm of transient climate change. Here we find that TCR explains more variability across Coupled Model Intercomparison Project phase 5 than ECS for global temperature change since preindustrial, for 50 or 100 year global trends up to the present, and for projected change under representative concentration pathways in regions of delayed warming such as the Southern Ocean. However, unexpectedly, we find that ECS correlates higher than TCR for projected change from the present in the global mean and in most regions. This higher correlation does not relate to aerosol forcing, and the physical cause requires further investigation.

  2. Is Shock Index a Valid Predictor of Mortality in Emergency Department Patients With Hypertension, Diabetes, High Age, or Receipt of β- or Calcium Channel Blockers?

    Kristensen, Anders K B; Holler, Jon G; Hallas, Jesper

    2016-01-01

    STUDY OBJECTIVE: Shock index is a widely reported tool to identify patients at risk for circulatory collapse. We hypothesize that old age, diabetes, hypertension, and β- or calcium channel blockers weaken the association between shock index and mortality. METHODS: This was a cohort study of all...... first-time emergency department (ED) visits between 1995 and 2011 (n=111,019). We examined whether age 65 years or older, diabetes, hypertension, and use of β- or calcium channel blockers modified the association between shock index and 30-day mortality. RESULTS: The 30-day mortality was 3.0%. For all...... than or equal to 1 in patients aged 65 years or older was 8.2 (95% CI 7.2 to 9.4) compared with 18.9 (95% CI 15.6 to 23.0) in younger patients. β- Or calcium channel-blocked patients had an OR of 6.4 (95% CI 4.9 to 8.3) versus 12.3 (95% CI 11.0 to 13.8) in nonusers and hypertensive patients had...

  3. Quantifying the effects of oil shocks on long-term public debt: A review of empirical data and a scenario analysis of future projections

    McMichael, Jillian Taylor

    Various authors have shown that each oil shock in the past 40 years has had statistically significant impacts on subsequent macroeconomic activity in the United States. Through these economic effects, oil shocks affect Federal revenues and expenditures and hence public debt. Published Federal budget scenarios do not currently reflect these impacts of oil shocks. I synthesize, in this paper, literature quantifying the impact of oil price increases on GDP growth and use that information to modify current long-term Federal budget models to present scenarios of how oil shocks are likely to affect long-term Federal debt. I argue that modeling the impact of oil price increases on long-term public debt could inform public policies, particularly those relating to Federal investments in energy conservation. Key Words: crude oil, oil shock, oil price spike, oil shock, Federal debt, debt projections, Congressional Budget Office

  4. INSPIA project: European Index for Sustainable and Productive Agriculture

    Triviño-Tarradas, Paula; Jesús González-Sánchez, Emilio; Gómez-Ariza, Manuel; Rass, Gerard; Gardette, Sophie; Whitmore, Gavin; Dyson, Jeremy

    2017-04-01

    Management (IPM). Therefore, the optimised use of agricultural technologies is considered to the extent they help farmers achieve their objectives, particularly their competitiveness. The principal BMPs flagged by CA that ensure biodiversity and environmental protection for a productive agriculture are based on minimum soil disturbance, permanent soil cover, and crop rotations. The project covers over 50 farms in Belgium, Denmark, France and Spain. INSPIA is promoting the uptake of sustainable agricultural practices throughout Europe by: • Raising awareness among EU policy stakeholders, technicians and farmers in favour of sustainable agriculture. • Recognition of farmers needs for helping dissemination of sustainable agriculture • Demonstrating that BMPs help to achieve sustainability in European agriculture. Provide a sustainable output graph based on a set of verifiable indicators; comparatives, evolution in time among others. • Consolidating a farm network in Belgium, Denmark, France and Spain to enable the validation, demonstration and communication of BMPs (first step), and extend this farm network to other countries (second step). Whereas the final objectives are: • Obtain adapted environmental and agricultural policies • Obtain recognition by farmers, decision makers and private sector of Sustainable Agriculture (Conservation Agriculture / ecological intensification with optimization across crop protection solutions) and of their operators (farmers in this system and their organizations / companies supportive)

  5. Core Abilities Evaluation Index System Exploration and Empirical Study on Distributed PV-Generation Projects

    Lin He

    2017-12-01

    Full Text Available In line with the constraints of environmental problems and economic development, large-scale renewable-generation projects have been planned and constructed in recent years. In order to achieve sustainable power development and improve the power supply structure, China’s government has focused on distributed photovoltaic (PV generation projects due to their advantages of clean emission and local consumption. However, their unstable output power still brings a series of problems concerning reliability, investment income, and available substitution proportion to traditional power, and so on. Therefore, it is imperative to understand the competitive development abilities of distributed PV generation projects and measure them effectively. First, through various investigation methods such as literature reviews, feasibility report analysis and expert interviews, the factors that influence the core abilities of distributed PV-generation projects were explored based on the micro-grid structure. Then, with the indexed exploration results, the factors were classified into 6 dimensions, i.e., investment and earning ability, production and operation ability, power-grid coordination ability, energy-conservation and emission-reduction ability, sustainable development ability, and society-serving ability. Meanwhile, an evaluation index system for core abilities of distributed PV-generation project was constructed using all quantitative indicators. Third, for examining the availability of the evaluation index system, combination weighting and techniques for order preference by similarity to an ideal solution (TOPSIS methods were adopted to assess the practical distributed PV-generation projects. The case study results showed that installed capacity, local economy development, and grid-connected power quantity will influence the core abilities of distributed PV-generation project, obviously. The conclusions of the evaluation analysis on core abilities can

  6. Using commodity-indexed financing to fund OPEC/Alaska's development projects

    Essayyad, Musa

    1992-01-01

    An impediment to the process of economic diversification in OPEC and Alaska is the lack of favourable access to local and international capital markets to finance development projects, particularly mineral resource development. This paper highlights the importance of commodity-indexed bonds, including oil- and gold- indexed bonds, as a financing alternative to supplement the supply shortage of loanable funds from conventional, local and international commercial banks. The indexation concept is discussed, features of different bonds issued to date are contrasted and the benefits and risks for borrowers and investors are highlighted. An analysis is made of the experience of OPEC and Alaska in using commodity-indexed bonds and the feasibility of Alaska and some OPEC countries entering into commodity-linked-financed joint ventures is examined. Future prospects for commodity-linked bonds are explored. Not withstanding the fact that the immediate market timing is unfavourable, the long-term benefits of commodity-indexed securities are recognized. (U.K.)

  7. Evaluation of the use of shock index in identifying acute blood loss in healthy blood donor dogs.

    McGowan, Erin E; Marryott, Kimberly; Drobatz, Kenneth J; Reineke, Erica L

    2017-09-01

    To determine if shock index (SI) would increase following blood donation and if it would be a more sensitive assessment of acute blood loss as compared with heart rate (HR), blood pressure, and plasma lactate. Prospective study. University teaching hospital. Twenty client-owned clinically normal dogs. Peripheral venous blood measurements and blood donation. Data were collected at 3 time points: prior to donation (T pre ), immediately after donation (T 0 ), and 10 minutes following completion of donation (T 10 ). HR and systolic blood pressure (SBP) were recorded and used to calculate SI at time points T pre , T 0 , and T 10 . Packed cell volume (PCV), total plasma protein (TPP), and plasma lactate were evaluated from a peripheral venous blood sample at T pre and T 10. The mean SI was significantly increased at both time points following blood donation as compared to baseline (SI pre = 0.88 ± 0.19 vs SI 0 = 1.17 ± 0.21 vs SI 10 = 1.12 ± 0.25 (P = 0.0002 and 0.0003, respectively). Following blood donation, the mean SBP was significantly lower (SBP pre = 149 ± 24 mm Hg, SBP 0 = 118 ± 20 mm Hg; P = 0.0001, SBP 10 = 133 ± 21 mm Hg; P = 0.011). The mean HR was not significantly different at T 0 but was significantly increased at T 10 (HR pre = 128 ± 21/min, HR 0 = 136 ± 25/min, P = 0.193; HR 10 = 146 ± 29/min, P = 0.003). There was no significant difference in mean PCV (PCV pre = 50 ± 4%, PCV 10 = 48 ± 4%, P = 0.08). The mean TPP and plasma lactate were significantly different following donation but still within the reference interval (TPP pre = 6.8 ± 0.4 g/dL, TPP 10 = 6.4 ± 0.4 g/dL, P = 0.0014; Lac pre = 1.7 ± 0.7mmol/L, Lac 10 = 1.9 ± 0.8 mmol/L, P = 0.04). A receiver operating characteristic (ROC) analysis comparing area under the curve (AUC) for SI, HR, and SBP at T 0 and T 10 compared to T pre found that SI (AUC at T 0 : 0.858, CI: 0.730, 0.984 AUC at T 10 : 0.769 CI: 0.617, 0.921) was a better indicator of blood loss

  8. An Index to Measure Sustainability of a Business Project in the Construction Industry: Lithuanian Case

    Nomeda Dobrovolskienė

    2015-12-01

    Full Text Available The continuous growth of the world population, resource scarcity and the threat of climate change pose numerous environmental and social problems to the world. Therefore, much hope is put in the concept of sustainability. Companies are increasingly coming under strong global pressure to incorporate sustainability considerations into their project decision-making process. Business projects in the construction industry are among the most important, as this sector is one of the largest sectors and of major importance for the national economy and therefore has a huge impact on the environment and society. Thus, we have to explore ways to integrate sustainability into the management of those projects. This paper presents a composite sustainability index of a project (CSIP which has been created following a review of existing literature and a pilot research study. A pilot research study was conducted in the Lithuanian construction industry between January 2015 and June 2015. Sustainability criteria were chosen and grouped on the basis of the analysis of the literature and different standards relating to sustainability applicable in the construction industry. A survey was used to select and rank the most important sustainability criteria. The index was constructed using multi-criteria decision-making methods. The results of the pilot study revealed that practitioners in the Lithuanian construction sector attach most importance to 15 sustainability criteria. A composite sustainability index of a project combining all these criteria may be useful in assessing the sustainability of a business project and making decisions regarding project portfolio selection and financial resource allocation. When addressing the issue of financial resource allocation in a project portfolio, the decision-maker could take into account not only the project’s return and risk, but also its sustainability. The understanding of this study should enable companies to execute

  9. Indexed

    Hagy, Jessica

    2008-01-01

    Jessica Hagy is a different kind of thinker. She has an astonishing talent for visualizing relationships, capturing in pictures what is difficult for most of us to express in words. At indexed.blogspot.com, she posts charts, graphs, and Venn diagrams drawn on index cards that reveal in a simple and intuitive way the large and small truths of modern life. Praised throughout the blogosphere as “brilliant,” “incredibly creative,” and “comic genius,” Jessica turns her incisive, deadpan sense of humor on everything from office politics to relationships to religion. With new material along with some of Jessica’s greatest hits, this utterly unique book will thrill readers who demand humor that makes them both laugh and think.

  10. Evaluation of the indexes of income yield capacity of energetic projects

    Villanueva M, C.

    2008-01-01

    An economic-financial model to evaluate in the class living room those indexes of profitability of projects of productive infrastructure of the energy sector was developed, as for example: generation projects, transmission and electric energy distribution; projects of transport and distribution of natural gas; projects of cogeneration of vapor and electricity; projects of refinement of petroleum; and other industrial projects. It is described the structure and operation of the pattern, which has been implemented in an Excel calculation sheet that the students use in their personal computers to apply it to the evaluation of the indexes of profitability, specified by the Secretaria de Hacienda y Credito Publico (SHCP) in their limits for the elaboration and presentation of the cost and benefit analysis of the programs and projects of investment of the public sector. The indicators are: present net value VPN, quotient benefits cost B/C, return internal rate TIR, and equivalent annual cost CAE, which should be calculated with methodological rigor according to the SHCP lineaments. The pattern uses the pre-programmed financial functions in the Excel calculation sheet to carry out the compute of the indicators starting from the effective flow of the projects. It is described the technician-economic configuration and the effective flows during the useful life of three power stations of electric power generation that are designed, builds and operated to sell electric power to the national interconnected system in a nodal marginal prices market: a hydroelectric one, a combined cycle power station that uses natural gas, and a nucleo electric. The effective flows are developed and the central profitability of three centrals are evaluated and they are also carried out the corresponding sensitivity analyses and indifference required by the SHCP in their lineaments. Finally, the conditions in that the projects should operate and the prices in those that should sell their

  11. The water reactor safety research project index: a description of the computerized system for its databank

    Della Loggia, E.; Primavera, R.

    1993-01-01

    The water reactor nuclear safety research project index has been published by the CEC for many years as a compilation of information on research projects relating to LWR nuclear safety. Since 1981, it has been published, alternatively with NEA (OECD), every second year. The number of contributions from research organizations in Community member countries has steadily increased and reached the level of 1 700 pages, in which more than 600 project descriptions have been collected. In 1988, for the first time, the document was produced using a computerized system developed with the assistance of the ISEI (Institute for Systems Engineering and Informatics) of JRC Ispra. The data have been stored in a computer based in Ispra. The system allows searching a preselected set of subjects through the information stored in the computer: it makes the updating of the projects description much easier and makes the retrieval of the data possible. This report presents a short description of the computerized system developed for the databank of the index. The computerized system presented in this report is structured in a quite general way and for that reason can be adapted very easily to every field where a databank needs to be constituted in order to collect extended information on several projects. (authors). 6 figs., 5 tabs., 5 refs

  12. IndexMed projects: new tools using the CIGESMED DataBase on Coralligenous for indexing, visualizing and data mining based on graphs

    David , Romain; FERAL , Jean-Pierre; Archambeau , Anne; Bailly , Nicolas; Blanpain , Cyrille; Breton , Vincent; De Jode , Aurélie; Delavaud , Aurélie; Dias , Alrick; Gachet , Sophie; Guillemain , Dorian; Lecubin , Julien; Romier , Geneviève; Surace , Christian; Thierry De Ville D 'avray , Laure

    2016-01-01

    International audience; Data produced by the CIGESMED project (Coralligenous based Indicators to evaluate and monitor the "Good Environmental Status" of the MEDiterranean coastal waters) have a high potential for use by several stakeholders involved in environmental management. A new consortium called IndexMed whose task is to index Mediterranean biodiversity data, makes it possible to build graphs in order to analyse the CIGESMED data and develop new ways for data mining of coralligenous dat...

  13. Designing Alternative Transport Methods for the Distributed Data Collection of ATLAS EventIndex Project

    Fernandez Casani, Alvaro; The ATLAS collaboration

    2016-01-01

    One of the key and challenging tasks of the ATLAS EventIndex project is to index and catalog all the produced events not only at CERN but also at hundreds of worldwide grid sites, and convey the data in real time to a central Hadoop instance at CERN. While this distributed data collection is currently operating correctly in production, there are some issues that might impose performance bottlenecks in the future, with an expected rise in the event production and reprocessing rates. In this work, we first describe the current approach based on a messaging system, which conveys the data from the sources to the central catalog, and we identify some weaknesses of this system. Then, we study a promising alternative transport method based on an object store, presenting a performance comparison with the current approach, and the architectural design changes needed to adapt the system to the next run of the ATLAS experiment at CERN.

  14. Experiment Study on Elastic Indicator of Thermal Shock Ceramic Materials——Implementation of Students’ Innovative Research Project of Shandong University of Science and Technology

    Wang Yanxia

    2017-01-01

    Full Text Available In order to improve the quality of undergraduate education and combine theory and practice, Shandong University of science and technology organized innovative research activities project for undergraduates. Combined with the characteristics of engineering mechanics course, teachers of engineering mechanics teaching and research section guided students to take an active part in scientific research and innovation practice teaching, which has obtained a good teaching effect. This paper introduces the concrete implement process of the college students’ innovative scientific research project “Experiment Study on Elastic Indicator of Thermal Shock Ceramic Materials”, which measures elastic indicator of ceramics using the ultrasonic method. This paper studies elastic indicator change rule of the mullite ceramic samples under different factors such as temperature difference, thermal shock times and so on. Studies have shown that in the condition of air-cooling, with the increase of thermal shock temperature difference and thermal shock times, the elastic modulus value, shear modulus and Poisson’s ratio are in a falling trend. The project implementation have proved that implement undergraduate innovation research projects could effectively arouse students’ learning enthusiasm, cultivate students’ scientific research innovation and analytical abilities to solve practical scientific research problems.

  15. Joint projections of sea level and storm surge using a flood index

    Little, C. M.; Lin, N.; Horton, R. M.; Kopp, R. E.; Oppenheimer, M.

    2016-02-01

    Capturing the joint influence of sea level rise (SLR) and tropical cyclones (TCs) on future coastal flood risk poses significant challenges. To address these difficulties, Little et al. (2015) use a proxy of tropical cyclone activity and a probabilistic flood index that aggregates flood height and duration over a wide area (the US East and Gulf coasts). This technique illuminates the individual impacts of TCs and SLR and their correlation across different coupled climate models. By 2080-2099, changes in the flood index relative to 1986-2005 are substantial and positively skewed: a 10th-90th percentile range of 35-350x higher for a high-end business-as-usual emissions scenario (see figure). This aggregated flood index: 1) is a means to consistently combine TC-driven storm surges and SLR; 2) provides a more robust description of historical surge-climate relationships than is available at any one location; and 3) allows the incorporation of a larger climate model ensemble - which is critical to uncertainty characterization. It does not provide a local view of the complete spectrum of flood severity (i.e. return curves). However, alternate techniques that provide localized return curves (e.g. Lin et al., 2012) are computationally intensive, limiting the set of large-scale climate models that can be incorporated, and require several linked statistical and dynamical models, each with structural uncertainties that are difficult to quantify. Here, we present the results of Little et al. (2015) along with: 1) alternate formulations of the flood index; 2) strategies to localize the flood index; and 3) a comparison of flood index projections to those provided by model-based return curves. We look to this interdisciplinary audience for feedback on the advantages and disadvantages of each tool for coastal planning and decision-making. Lin, N., K. Emanuel, M. Oppenheimer, and E. Vanmarcke, 2012: Physically based assessment of hurricane surge threat under climate change. Nature

  16. The projected relative index of consequence equivalence of transport of radioactive materials

    Nandakumar, A.N.

    1999-01-01

    The need exists for defining a unit risk factor to enable analysis to make a proper decision when faced with many options relating to the transport of radioactive materials between sites. A method is discussed for deriving such a factor with reference to the collective dose receivable due to the transport of radioactive material incidental to the production of one GWe.a of nuclear power. This quantity would enable the analyst to determine the projected relative index of consequence equivalence (PRICE) for the transport of various types of radioactive materials. (author)

  17. Inventory of Federal energy-related environment and safety research for FY 1978. Volume II. Project listings and indexes

    None

    1979-12-01

    This volume contains summaries of FY-1978 government-sponsored environment and safety research related to energy. Project summaries were collected by Aerospace Corporation under contract with the Department of Energy, Office of Program Coordination, under the Assistant Secretary for Environment. Summaries are arranged by log number, which groups the projects by reporting agency. The log number is a unique number assigned to each project from a block of numbers set aside for each agency. Information about the projects is included in the summary listings. This includes the project title, principal investigators, research organization, project number, contract number, supporting organization, funding level if known, related energy sources with numbers indicating percentages of effort devoted to each, and R and D categories. A brief description of each project is given, and this is followed by subject index terms that were assigned for computer searching and for generating the printed subject index in Volume IV.

  18. Inventory of Federal energy-related environment and safety research for FY 1978. Volume II. Project listings and indexes

    1979-12-01

    This volume contains summaries of FY-1978 government-sponsored environment and safety research related to energy. Project summaries were collected by Aerospace Corporation under contract with the Department of Energy, Office of Program Coordination, under the Assistant Secretary for Environment. Summaries are arranged by log number, which groups the projects by reporting agency. The log number is a unique number assigned to each project from a block of numbers set aside for each agency. Information about the projects is included in the summary listings. This includes the project title, principal investigators, research organization, project number, contract number, supporting organization, funding level if known, related energy sources with numbers indicating percentages of effort devoted to each, and R and D categories. A brief description of each project is given, and this is followed by subject index terms that were assigned for computer searching and for generating the printed subject index in Volume IV

  19. Return on Scientific Investment - RoSI: a PMO dynamical index proposal for scientific projects performance evaluation and management.

    Caous, Cristofer André; Machado, Birajara; Hors, Cora; Zeh, Andrea Kaufmann; Dias, Cleber Gustavo; Amaro Junior, Edson

    2012-01-01

    To propose a measure (index) of expected risks to evaluate and follow up the performance analysis of research projects involving financial and adequate structure parameters for its development. A ranking of acceptable results regarding research projects with complex variables was used as an index to gauge a project performance. In order to implement this method the ulcer index as the basic model to accommodate the following variables was applied: costs, high impact publication, fund raising, and patent registry. The proposed structured analysis, named here as RoSI (Return on Scientific Investment) comprises a pipeline of analysis to characterize the risk based on a modeling tool that comprises multiple variables interacting in semi-quantitatively environments. This method was tested with data from three different projects in our Institution (projects A, B and C). Different curves reflected the ulcer indexes identifying the project that may have a minor risk (project C) related to development and expected results according to initial or full investment. The results showed that this model contributes significantly to the analysis of risk and planning as well as to the definition of necessary investments that consider contingency actions with benefits to the different stakeholders: the investor or donor, the project manager and the researchers.

  20. Body mass index and buttock circumference are independent predictors of disintegration failure in extracorporeal shock wave lithotripsy for ureteral calculi.

    Yang, Teng-Kai; Yang, Hung-Ju; Lee, Liang-Min; Liao, Chun-Hou

    2013-07-01

    Effective stone disintegration by extracorporeal shockwave lithotripsy (ESWL) may depend on patient- and stone-related factors. We investigated predictors of disintegration failure in ESWL for a solitary ureteral calculus. From July 2008 to May 2010, 203 patients who underwent ESWL for a solitary ureteral calculus were enrolled. Clinical and radiologic data were collected, and factors related to ESWL failure were analyzed. Fifty-two patients (25.6%) showed ESWL failure, with a mean follow-up of 41 days. Forty patients (19.7%) required retreatment, including 12 who underwent repeat ESWL and 28 who underwent curative ureteroscopy. Patients with ESWL failure had significantly higher body weight, body mass index (BMI), and buttock circumference (BC) than patients for whom ESWL was successful. Univariate analysis showed that stone burden (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.03-1.06) and BC (OR, 1.06; 95% CI, 1.01-1.11) were predictors of ESWL failure, while BMI was a potential predictor with borderline significance (OR, 1.09; 95% CI, 0.99-1.20). Multivariate analysis showed that stone burden (OR, 1.04; 95% CI, 1.03-1.06) was a significant predictor for all patients. On stratifying patients according to the level of ureteral calculi, BC was found to be an independent predictor (OR, 1.35; 95% CI, 1.02-1.80) for ESWL failure for middle/lower ureteral calculi and BMI (OR, 1.47; 95% CI, 1.13-1.91) for upper ureteral calculi. Stone burden is the main predictor of ESWL failure for all patients with ureteral calculi. BC and BMI are independent predictors for ESWL failure for middle/lower and upper ureteral calculi, respectively. Copyright © 2012. Published by Elsevier B.V.

  1. Stone heterogeneity index as the standard deviation of Hounsfield units: A novel predictor for shock-wave lithotripsy outcomes in ureter calculi.

    Lee, Joo Yong; Kim, Jae Heon; Kang, Dong Hyuk; Chung, Doo Yong; Lee, Dae Hun; Do Jung, Hae; Kwon, Jong Kyou; Cho, Kang Su

    2016-04-01

    We investigated whether stone heterogeneity index (SHI), which a proxy of such variations, was defined as the standard deviation of a Hounsfield unit (HU) on non-contrast computed tomography (NCCT), can be a novel predictor for shock-wave lithotripsy (SWL) outcomes in patients with ureteral stones. Medical records were obtained from the consecutive database of 1,519 patients who underwent the first session of SWL for urinary stones between 2005 and 2013. Ultimately, 604 patients with radiopaque ureteral stones were eligible for this study. Stone related variables including stone size, mean stone density (MSD), skin-to-stone distance, and SHI were obtained on NCCT. Patients were classified into the low and high SHI groups using mean SHI and compared. One-session success rate in the high SHI group was better than in the low SHI group (74.3% vs. 63.9%, P = 0.008). Multivariate logistic regression analyses revealed that smaller stone size (OR 0.889, 95% CI: 0.841-0.937, P < 0.001), lower MSD (OR 0.995, 95% CI: 0.994-0.996, P < 0.001), and higher SHI (OR 1.011, 95% CI: 1.008-1.014, P < 0.001) were independent predictors of one-session success. The radiologic heterogeneity of urinary stones or SHI was an independent predictor for SWL success in patients with ureteral calculi and a useful clinical parameter for stone fragility.

  2. Association of different electrocardiographic patterns with shock index, right ventricle systolic pressure and diameter, and embolic burden score in pulmonary embolism

    Krća Bojana

    2016-01-01

    Full Text Available Background/Aim. Some electrocardiographic (ECG patterns are characteristic for pulmonary embolism but exact meaning of the different ECG signs are not well known. The aim of this study was to determine the association between four common ECG signs in pulmonary embolism [complete or incomplete right bundle branch block (RBBB, S-waves in the aVL lead, S1Q3T3 sign and negative T-waves in the precordial leads] with shock index (SI, right ventricle diastolic diameter (RVDD and peak systolic pressure (RVSP and embolic burden score (EBS. Methods. The presence of complete or incomplete RBBB, S waves in aVL lead, S1Q3T3 sign and negative T-waves in the precordial leads were determined at admission ECG in 130 consecutive patients admitted to the intensive care unit of a single tertiary medical center in a 5-year period. Echocardiography examination with measurement of RVDD and RVSP, multidetector computed tomography pulmonary angiography (MDCT-PA with the calculation of EBS and SI was determined during the admission process. Multivariable regression models were calculated with ECG parameters as independent variables and the mentioned ultrasound, MDCT-PA parameters and SI as dependent variables. Results. The presence of S-waves in the aVL was the only independent predictor of RVDD (F = 39.430, p < 0.001; adjusted R2 = 0.231 and systolic peak right ventricle pressure (F = 29.903, p < 0.001; adjusted R2 = 0.185. Negative T-waves in precordial leads were the only independent predictor for EBS (F = 24.177, p < 0.001; R2 = 0.160. Complete or incomplete RBBB was the independent predictor of SI (F = 20.980, p < 0.001; adjusted R2 = 0.134. Conclusion. In patients with pulmonary embolism different ECG patterns at admission correlate with different clinical, ultrasound and MDCT-PA parameters. RBBB is associated with shock, Swave in the aVL is associated with right ventricle pressure and negative T-waves with the thrombus burden in the pulmonary tree.

  3. Inventory of Federal energy-related environment and safety research for FY 1979. Volume II. Project listings and indexes

    None

    1980-12-01

    This volume contains summaries of FY 1979 government-sponsored environment and safety research related to energy arranged by log number, which groups the projects by reporting agency. The log number is a unique number assigned to each project from a block of numbers set aside for each contributing agency. Information elements included in the summary listings are project title, principal investigators, research organization, project number, contract number, supporting organization, funding level, related energy sources with numbers indicating percentages of effort devoted to each, and R and D categories. A brief description of each project is given, and this is followed by subject index terms that were assigned for computer searching and for generating the printed subject index in the back of this volume.

  4. Inventory of Federal energy-related environment and safety research for FY 1979. Volume II. Project listings and indexes

    1980-12-01

    This volume contains summaries of FY 1979 government-sponsored environment and safety research related to energy arranged by log number, which groups the projects by reporting agency. The log number is a unique number assigned to each project from a block of numbers set aside for each contributing agency. Information elements included in the summary listings are project title, principal investigators, research organization, project number, contract number, supporting organization, funding level, related energy sources with numbers indicating percentages of effort devoted to each, and R and D categories. A brief description of each project is given, and this is followed by subject index terms that were assigned for computer searching and for generating the printed subject index in the back of this volume

  5. Effects of temperature-humidity index and chromium supplementation on antioxidant capacity, heat shock protein 72, and cytokine responses of lactating cows.

    Zhang, F J; Weng, X G; Wang, J F; Zhou, D; Zhang, W; Zhai, C C; Hou, Y X; Zhu, Y H

    2014-07-01

    Heat stress adversely affects the productivity and immune status of dairy cows. The temperature-humidity index (THI) is commonly used to indicate the degree of heat stress on dairy cattle. We investigated the effects of different THI and Cr supplementation on the antioxidant capacity, the levels of heat shock protein 72 (Hsp72), and cytokine responses of lactating cows. The study used a total of 24 clinically healthy uniparous midlactation Holstein cows, which were randomly divided into 2 groups (n = 12 per group), and was conducted in 3 designated THI periods: low THI period (LTHI; THI = 56.4 ± 2.5), moderate THI period (MTHI; THI = 73.9 ± 1.7), and high THI period (HTHI; THI = 80.3 ± 1.0). The 2 groups of cows were fed corn and corn silage based basal diet supplemented chromium picolinate to provide 3.5 mg of Cr/cow daily (Cr+) or basal diet with no Cr (Cr-). The experiment was a 3 × 2 factorial design. The numbers of leukocytes (P Cows supplemented with Cr had lower (P = 0.009) serum concentrations of cholesterol but greater (P cows supplemented with Cr had greater (P = 0.038) expression of the inhibitor of nuclear factor kappa B α (IκBα) in peripheral blood mononuclear cells (PBMC) compared with those without Cr supplementation in the HTHI, whereas the expression of Hsp72 in PBMC was unaltered. Data indicate that there is a decrease in glucose and increases in BUN and creatinine in the serum of midlactation cows under hot conditions during the summer and that these cows have a lowered oxidative capacity but an elevated antioxidant capacity. In addition, Cr may play an anti-inflammatory role in lactating cows by promoting the release of Hsp72, increasing the production of IL-10, and inhibiting the degradation of IκBα under hot conditions during the summer.

  6. Return on Scientific Investment – RoSI: a PMO dynamical index proposal for scientific projects performance evaluation and management

    Cristofer André Caous

    2012-06-01

    Full Text Available Objective: To propose a measure (index of expected risks to evaluateand follow up the performance analysis of research projects involvingfinancial and adequate structure parameters for its development.Methods: A ranking of acceptable results regarding researchprojects with complex variables was used as an index to gauge aproject performance. In order to implement this method the ulcerindex as the basic model to accommodate the following variableswas applied: costs, high impact publication, fund raising, and patentregistry. The proposed structured analysis, named here as RoSI(Return on Scientific Investment comprises a pipeline of analysis tocharacterize the risk based on a modeling tool that comprises multiplevariables interacting in semi-quantitatively environments. Results:This method was tested with data from three different projects in ourInstitution (projects A, B and C. Different curves reflected the ulcer indexes identifying the project that may have a minor risk (project C related to development and expected results according to initial or full investment. Conclusion: The results showed that this model contributes significantly to the analysis of risk and planning as well as to the definition of necessary investments that consider contingency actions with benefits to the different stakeholders: the investor or donor, the project manager and the researchers.

  7. Bayesian spatial prediction of the site index in the study of the Missouri Ozark Forest Ecosystem Project

    Xiaoqian Sun; Zhuoqiong He; John Kabrick

    2008-01-01

    This paper presents a Bayesian spatial method for analysing the site index data from the Missouri Ozark Forest Ecosystem Project (MOFEP). Based on ecological background and availability, we select three variables, the aspect class, the soil depth and the land type association as covariates for analysis. To allow great flexibility of the smoothness of the random field,...

  8. Prehospital shock index and pulse pressure/heart rate ratio to predict massive transfusion after severe trauma: Retrospective analysis of a large regional trauma database.

    Pottecher, Julien; Ageron, François-Xavier; Fauché, Clémence; Chemla, Denis; Noll, Eric; Duranteau, Jacques; Chapiteau, Laurent; Payen, Jean-François; Bouzat, Pierre

    2016-10-01

    Early and accurate detection of severe hemorrhage is critical for a timely trigger of massive transfusion (MT). Hemodynamic indices combining heart rate (HR) and either systolic (shock index [SI]) or pulse pressure (PP) (PP/HR ratio) have been shown to track blood loss during hemorrhage. The present study assessed the accuracy of prehospital SI and PP/HR ratio to predict subsequent MT, using the gray-zone approach. This was a retrospective analysis (January 1, 2009, to December 31, 2011) of a prospectively developed trauma registry (TRENAU), in which the triage scheme combines patient severity and hospital facilities. Thresholds for MT were defined as either classic (≥10 red blood cell units within the first 24 hours [MT1]) or critical (≥3 red blood cells within the first hour [MT2]). The receiver operating characteristic curves and gray zones were defined for SI and PP/HR ratio to predict MT1 and MT2 and faced with initial triage scheme. The TRENAU registry included 3,689 trauma patients, of which 2,557 had complete chart recovery and 176 (6.9%) required MT. In the whole population, PP/HR ratio and SI moderately and similarly predicted MT1 (area under the receiver operating characteristic curve, 0.77 [95% confidence interval {CI}, 0.70-0.84] and 0.80 [95% CI, 0.74-0.87], respectively, p = 0.064) and MT2 (0.71 [95% CI, 0.67-0.76] and 0.72 [95% CI, 0.68-0.77], respectively, p = 0.48). The proportions of patients in the gray zone for PP/HR ratio and SI were 61% versus 40%, respectively, to predict MT1 (p ratio outperformed SI to predict MT2 (0.72 [95% CI, 0.59-0.84] vs. 0.54 [95% CI, 0.33-0.74]; p ratio were moderately accurate in predicting MT. In the seemingly least severe patients, an improvement of prehospital undertriage for MT may be gained by using the PP/HR ratio. Epidemiolgic study, level III.

  9. Shock Prevention

    1978-01-01

    The electrician pictured is installing a General Electric Ground Fault Interrupter (GFI), a device which provides protection against electrical shock in the home or in industrial facilities. Shocks due to defective wiring in home appliances or other electrical equipment can cause severe burns, even death. As a result, the National Electrical Code now requires GFIs in all new homes constructed. This particular type of GFI employs a sensing element which derives from technology acquired in space projects by SCI Systems, Inc., Huntsville, Alabama, producer of sensors for GE and other manufacturers of GFI equipment. The sensor is based on the company's experience in developing miniaturized circuitry for space telemetry and other spacecraft electrical systems; this experience enabled SCI to package interruptor circuitry in the extremely limited space available and to produce sensory devices at practicable cost. The tiny sensor measures the strength of the electrical current and detects current differentials that indicate a fault in the functioning of an electrical system. The sensing element then triggers a signal to a disconnect mechanism in the GFI, which cuts off the current in the faulty circuit.

  10. Evaluation of the indexes of income yield capacity of energetic projects; Evaluacion de los indices de rentabilidad de proyectos energeticos

    Villanueva M, C. [Facultad de Quimica, UNAM, 04510 Mexico D.F. (Mexico)

    2008-07-01

    An economic-financial model to evaluate in the class living room those indexes of profitability of projects of productive infrastructure of the energy sector was developed, as for example: generation projects, transmission and electric energy distribution; projects of transport and distribution of natural gas; projects of cogeneration of vapor and electricity; projects of refinement of petroleum; and other industrial projects. It is described the structure and operation of the pattern, which has been implemented in an Excel calculation sheet that the students use in their personal computers to apply it to the evaluation of the indexes of profitability, specified by the Secretaria de Hacienda y Credito Publico (SHCP) in their limits for the elaboration and presentation of the cost and benefit analysis of the programs and projects of investment of the public sector. The indicators are: present net value VPN, quotient benefits cost B/C, return internal rate TIR, and equivalent annual cost CAE, which should be calculated with methodological rigor according to the SHCP lineaments. The pattern uses the pre-programmed financial functions in the Excel calculation sheet to carry out the compute of the indicators starting from the effective flow of the projects. It is described the technician-economic configuration and the effective flows during the useful life of three power stations of electric power generation that are designed, builds and operated to sell electric power to the national interconnected system in a nodal marginal prices market: a hydroelectric one, a combined cycle power station that uses natural gas, and a nucleo electric. The effective flows are developed and the central profitability of three centrals are evaluated and they are also carried out the corresponding sensitivity analyses and indifference required by the SHCP in their lineaments. Finally, the conditions in that the projects should operate and the prices in those that should sell their

  11. Case Study Application of the Biodiversity Security Index to Ranking Feasibility Studies for Ecosystem Restoration Projects of the U.S. Army Corps of Engineers

    2016-04-01

    ER D C/ EL C R- 16 -1 Ecosystem Management and Restoration Research Program Case Study Application of the Biodiversity Security Index... Biodiversity Security Index to Ranking Feasibility Studies for Ecosystem Restoration Projects of the U.S. Army Corps of Engineers Richard A. Cole... Biodiversity Security Index (BSI) was applied to 23 project sites ranked for restoration feasibility study annual funding by the U. S. Army Corps of

  12. Body Mass Index (BMI) and All-Cause Mortality Pooling Project

    The BMI and All-Cause Mortality Pooling Project quantified the risk associated with being overweight and the extent to which the relationship between BMI and all-cause mortality varies by certain factors.

  13. EPA Office of Water (OW): Nonpoint Source Projects NHDPlus Indexed Dataset

    U.S. Environmental Protection Agency — GRTS locational data for nonpoint source projects. GRTS locations are coded onto NHDPlus v2.1 flowline features to create point and line events or coded onto NHDPlus...

  14. Core Abilities Evaluation Index System Exploration and Empirical Study on Distributed PV-Generation Projects

    Lin He; Chang-Ling Li; Qing-Yun Nie; Yan Men; Hai Shao; Jiang Zhu

    2017-01-01

    In line with the constraints of environmental problems and economic development, large-scale renewable-generation projects have been planned and constructed in recent years. In order to achieve sustainable power development and improve the power supply structure, China’s government has focused on distributed photovoltaic (PV) generation projects due to their advantages of clean emission and local consumption. However, their unstable output power still brings a series of problems concerning re...

  15. Distributed Data Collection For Next Generation ATLAS EventIndex Project

    Fernandez Casani, Alvaro; The ATLAS collaboration

    2018-01-01

    The ATLAS EventIndex currently runs in production in order to build a complete catalogue of events for experiments with large amounts of data. The current approach is to index all final produced data files at CERN Tier0, and at hundreds of grid sites, with a distributed data collection architecture using Object Stores to temporary maintain the conveyed information, with references to them sent with a Messaging System. The final backend of all the indexed data is a central Hadoop infrastructure at CERN; an Oracle relational database is used for faster access to a subset of this information. In the future of ATLAS, instead of files, the event should be the atomic information unit for metadata. This motivation arises in order to accommodate future data processing and storage technologies. Files will no longer be static quantities, possibly dynamically aggregating data, and also allowing event-level granularity processing in heavily parallel computing environments. It also simplifies the handling of loss and or e...

  16. A Project Strategic Index proposal for portfolio selection in electrical company based on the Analytic Network Process

    Smith-Perera, Aida [Universidad Metropolitana de Caracas, Departamento de Gestion Tecnologica, Caracas 1071, Edo Miranda (Venezuela); Garcia-Melon, Monica; Poveda-Bautista, Rocio; Pastor-Ferrando, Juan-Pascual [Universidad Politecnica de Valencia, Departamento de Proyectos de Ingenieria, Camino de vera s/n 46022 Valencia (Spain)

    2010-08-15

    In this paper a new approach to prioritize project portfolio in an efficient and reliable way is presented. It is based on strategic objectives of the company and multicriteria decision methods. The paper introduces a rigorous method with acceptable complexity which seeks to assist managers of a big Electrical Company of Venezuela to distribute the annual budget among the possible improvement actions to be conducted on the electrical network of Caracas. A total of 15 network improvement actions grouped into three clusters according to the strategic objectives of the company have been analyzed using the Project Strategic Index (PSI) proposed. The approach combines the use of the Analytic Network Process (ANP) method with the information obtained from the experts during the decision-making process. The ANP method allows the aggregation of the experts' judgments on each of the indicators used into one Project Strategic Index. In addition, ANP is based on utility ratio functions which are the most appropriate for the analysis of uncertain data, like experts' estimations. Finally, unlike the other multicriteria techniques, ANP allows the decision problem to be modelled using the relationships among dependent criteria. The participating experts coincided in the appreciation that the method proposed in this paper is useful and an improvement from traditional budget distribution techniques. They find the results obtained coherent, the process seems sufficiently rigorous and precise, and the use of resources is significantly less than in other methods. (author)

  17. A Project Strategic Index proposal for portfolio selection in electrical company based on the Analytic Network Process

    Smith-Perera, Aida; Garcia-Melon, Monica; Poveda-Bautista, Rocio; Pastor-Ferrando, Juan-Pascual

    2010-01-01

    In this paper a new approach to prioritize project portfolio in an efficient and reliable way is presented. It is based on strategic objectives of the company and multicriteria decision methods. The paper introduces a rigorous method with acceptable complexity which seeks to assist managers of a big Electrical Company of Venezuela to distribute the annual budget among the possible improvement actions to be conducted on the electrical network of Caracas. A total of 15 network improvement actions grouped into three clusters according to the strategic objectives of the company have been analyzed using the Project Strategic Index (PSI) proposed. The approach combines the use of the Analytic Network Process (ANP) method with the information obtained from the experts during the decision-making process. The ANP method allows the aggregation of the experts' judgments on each of the indicators used into one Project Strategic Index. In addition, ANP is based on utility ratio functions which are the most appropriate for the analysis of uncertain data, like experts' estimations. Finally, unlike the other multicriteria techniques, ANP allows the decision problem to be modelled using the relationships among dependent criteria. The participating experts coincided in the appreciation that the method proposed in this paper is useful and an improvement from traditional budget distribution techniques. They find the results obtained coherent, the process seems sufficiently rigorous and precise, and the use of resources is significantly less than in other methods. (author)

  18. The method and index of sustainability assessment of infrastructure projects based on system dynamics in China

    Jun Zhou

    2015-05-01

    Full Text Available Purpose: As one of the most important overhead capital of urban economics and social development, the sustainable development of urban infrastructure is becoming a key issue of prosperous society growing. The purpose of this paper is to establish a basic model to analysis certain infrastructure project’s sustainable construction and operation. Design/methodology/approach: System dynamics is an effective stimulation method and tool to deal with such complex, dynamics, nonlinear systems, which could be used in analyzing and evaluating all aspects of infrastructure sustainability internally and externally. In this paper, the system is divided into four subsystems and 12 main impact indicators. Through setting the boundary and other basic hypothesis, this paper designs the basic causal loop diagrams and stock & flow diagrams to describe the relationship between variables and establish a quantifiable structure for the system. Findings: Adopting a sewerage treatment in China as a case to test our model, we could conclude that the model of internal sustainable subsystem is reasonable. However, this model is a basic model, and it need to be specific designed for the certain project due to the diversity of infrastructure types and the unique conditions of each projects. Originality/value: System Dynamics (SD is widely used in the study of sustainable development and has plentiful research achievements from macro perspective but few studies in the microcosmic project systems. This paper focuses on the unique characteristics of urban infrastructure in China and selects infrastructure project which is based on micro-system discussion. The model we designed has certain practical significance in policy setting, operation monitoring and adjustment of the urban projects with high rationality and accuracy.

  19. Possible pressurized thermal shock events during large primary to secondary leakage. The Hungarian AGNES project and PRISE accident scenarios in VVER-440/V213 type reactor

    Perneczky, L. [KFKI Atomic Energy Research Inst., Budabest (Hungary)

    1997-12-31

    Nuclear power plants of WWER-440/213-type have several special features. Consequently, the transient behaviour of such a reactor system should be different from the behaviour of the PWRs of western design. The opening of the steam generator (SG) collector cover, as a specific primary to secondary circuit leakage (PRISE) occurring in WWER-type reactors happened first time in Rovno NPP Unit I on January 22, 1982. Similar accident was studied in the framework of IAEA project RER/9/004 in 1987-88 using the RELAP4/mod6 code. The Hungarian AGNES (Advanced General and New Evaluation of Safety) project was performed in the period 1991-94 with the aim to reassess the safety of the Paks NPP using state-of-the-art techniques. The project comprised three type of analyses for the primary to secondary circuit leakages: Design Basis Accident (DBA) analyses, Pressurized Thermal Shock (PTS) study and deterministic analyses for Probabilistic Safety Analysis (PSA). Major part of the thermohydraulic analyses has been performed by the RELAP5/mod2.5/V251 code version with two input models. 32 refs.

  20. Possible pressurized thermal shock events during large primary to secondary leakage. The Hungarian AGNES project and PRISE accident scenarios in VVER-440/V213 type reactor

    Perneczky, L [KFKI Atomic Energy Research Inst., Budabest (Hungary)

    1998-12-31

    Nuclear power plants of WWER-440/213-type have several special features. Consequently, the transient behaviour of such a reactor system should be different from the behaviour of the PWRs of western design. The opening of the steam generator (SG) collector cover, as a specific primary to secondary circuit leakage (PRISE) occurring in WWER-type reactors happened first time in Rovno NPP Unit I on January 22, 1982. Similar accident was studied in the framework of IAEA project RER/9/004 in 1987-88 using the RELAP4/mod6 code. The Hungarian AGNES (Advanced General and New Evaluation of Safety) project was performed in the period 1991-94 with the aim to reassess the safety of the Paks NPP using state-of-the-art techniques. The project comprised three type of analyses for the primary to secondary circuit leakages: Design Basis Accident (DBA) analyses, Pressurized Thermal Shock (PTS) study and deterministic analyses for Probabilistic Safety Analysis (PSA). Major part of the thermohydraulic analyses has been performed by the RELAP5/mod2.5/V251 code version with two input models. 32 refs.

  1. Shock absorber

    Nemeth, J.D.

    1981-01-01

    A shock absorber for the support of piping and components in a nuclear power plant is described. It combines a high degree of stiffness under sudden shocks, e.g. seismic disturbances, with the ability to allow for thermal expansion without resistance when so required. (JIW)

  2. Compendium of shock wave data. Section C. Organic compounds excluding hydrocarbons. Section D. Mixtures. Section E. Mixtures and solutions without chemical characterization. Compendium index

    van Thiel, M.; shaner, J.; Salinas, E.

    1977-06-01

    This volume lists thermodynamic data for organic compounds excluding hydrocarbons, mixtures, and mixtures and solutions without chemical characterization. Alloys and some minerals are included among the mixtures. This volume also contains the index for the three-volume compendium

  3. The Impact of Tax Shocks and Oil Price Volatility on Risk - A Study of North Sea Oilfield Projects

    Kretzschmar, Gavin Lee; Moles, Peter

    2006-01-01

    We examine the impact of market volatility and increased fiscal take on risk in strategic natural resource projects. An increase in 2006 UK oilfield taxation is used as a natural experiment for assessing the impact of a fiscal increase on oilfield projects comprising 73% of UK reserves. Stochastic cash flow at risk models combine market volatility and tax-take at the oilfield level to extend earlier North Sea studies. We demonstrate that a 10% Secondary tax increase in a composite UKCS fiscal...

  4. demystifying the shock of shocking

    (with a pulse), atrial fibrillation and atrial flutter. The energy dose in cardioversion is less (0.5. - 2 J/kg) than in defibrillation (2 - 4 J/kg). In cardioversion the shock is discharged synchronously with the native R wave of the patient. Without synchronisation,. VF can be induced if a shock is delivered during the refractory period ...

  5. Dietary indexes, food patterns and incidence of metabolic syndrome in a Mediterranean cohort: The SUN project.

    Pimenta, Adriano M; Toledo, Estefanía; Rodriguez-Diez, Maria C; Gea, Alfredo; Lopez-Iracheta, Roberto; Shivappa, Nitin; Hébert, James R; Martinez-Gonzalez, Miguel A

    2015-06-01

    We prospectively assessed the association between adherence to several a priori defined healthy food patterns and risk of metabolic syndrome (MetS). We assessed 6851 participants of a Spanish dynamic prospective cohort of university graduates, initially free of any MetS-specific definition criteria, and followed-up for a median of 8.3 years. We calculated the adherence to thirteen different a priori defined food patterns or dietary indexes. MetS was classified according to the updated harmonizing criteria. We estimated multivariable-adjusted Incidence Rate Ratios (IRR) of metabolic syndrome and their 95% Confidence Intervals (95% CI), using Poisson regression models. The cumulative incidence of MetS was 5.0%. Moderate adherence to the Pro-Vegetarian Diet (PVEG) was significantly associated with a lower risk for developing MetS (IRR = 0.75, 95% CI = 0.59-0.97). Among women, an inverse association with the PVEG was significant not only for a moderate adherence (IRR = 0.54, 95% CI = 0.36-0.82), but also for higher adherence (IRR = 0.63, 95% CI = 0.43-0.93). A higher adherence to the Dietary Approaches to Stop Hypertension (DASH) diet showed an inverse association with the MetS among participants, but only if they had low alcohol intake (RR = 0.41, 95% CI = 0.20-0.85). Our findings support the adoption of a PVEG dietary pattern for the reduction of MetS risk. The same statement can be applied in relation to the DASH diet, insofar a limited consumption of alcoholic beverages is also maintained. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  6. Relativistic shocks and particle acceleration

    Heavens, A.F.

    1988-01-01

    In this paper, we investigate the fluid dynamics of relativistic shock waves, and use the results to calculate the spectral index of particles accelerated by the Fermi process in such shocks. We have calculated the distributions of Fermi-accelerated particles at shocks propagating into cold proton-electron plasma and also cold electron-positron plasma. We have considered two different power spectra for the scattering waves, and find, in contrast to the non-relativistic case, that the spectral index of the accelerated particles depends on the wave power spectrum. On the assumption of thermal equilibrium both upstream and downstream, we present some useful fits for the compression ratio of shocks propagating at arbitrary speeds into gas of any temperature. (author)

  7. Reverse shock index multiplied by Glasgow Coma Scale score (rSIG) is a simple measure with high discriminant ability for mortality risk in trauma patients: an analysis of the Japan Trauma Data Bank.

    Kimura, Akio; Tanaka, Noriko

    2018-04-11

    The shock index (SI), defined as heart rate (HR) divided by systolic blood pressure (SBP), is reported to be a more sensitive marker of shock than traditional vital signs alone. In previous literature, use of the reverse shock index (rSI), taken as SBP divided by HR, is recommended instead of SI for hospital triage. Among traumatized patients aged > 55 years, SI multiplied by age (SIA) might provide better prediction of early post-injury mortality. Separately, the Glasgow Coma Scale (GCS) score has been shown to be a very strong predictor. When considering these points together, rSI multiplied by GCS score (rSIG) or rSIG divided by age (rSIG/A) could provide even better prediction of in-hospital mortality. This retrospective, multicenter study used data from 168,517 patients registered in the Japan Trauma Data Bank for the period 2006-2015. We calculated areas under receiver operating characteristic curves (AUROCs) to measure the discriminant ability by comparing those of SI (or rSI), SIA, rSIG, and rSIG/A for in-hospital mortality and for 24-h blood transfusion. The highest ROC AUC (AUROC), 0.901(0.894-0.908) for in-hospital mortality in younger patients (aged < 55 years), was seen for rSIG. In older patients (aged ≥ 55 years), the AUROC of rSIG/A, 0.845(0.840-0.850), was highest for in-hospital mortality. However, the difference between rSIG and rSIG/A was slight and did not seem to be clinically important. rSIG also had the highest AUROC of 0.745 (0.741-749) for 24-h blood transfusion. rSIG ((SBP/HR) × GCS score) is easy to calculate without the need for additional information, charts or equipment, and can be a more reliable triage tool for identifying risk levels in trauma patients.

  8. Hypovolemic shock

    ... the person's position unless they are in immediate danger. Do not give fluids by mouth. If person ... the patient with shock. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: ...

  9. Shock absorber

    Housman, J.J.

    1978-01-01

    A shock absorber is described for use in a hostile environment at the end of a blind passage for absorbing impact loads. The shock absorber includes at least one element which occupies the passage and which is comprised of a porous brittle material which is substantially non-degradable in the hostile environment. A void volume is provided in the element to enable the element to absorb a predetermined level of energy upon being crushed due to impact loading

  10. The relation of body mass index and abdominal adiposity with dyslipidemia in 27 general populations of the WHO MONICA Project

    Wietlisbach, V; Marques-Vidal, P; Kuulasmaa, K

    2013-01-01

    BACKGROUND AND AIMS: The association between adiposity measures and dyslipidemia has seldom been assessed in a multipopulational setting. METHODS AND RESULTS: 27 populations from Europe, Australia, New Zealand and Canada (WHO MONICA project) using health surveys conducted between 1990 and 1997...... in adults aged 35-64 years (n = 40,480). Dyslipidemia was defined as the total/HDL cholesterol ratio >6 (men) and >5 (women). Overall prevalence of dyslipidemia was 25% in men and 23% in women. Logistic regression showed that dyslipidemia was strongly associated with body mass index (BMI) in men......, do not lead to optimal risk stratification for dyslipidemia in middle-age adults. Sex-specific adaptations are necessary, in particular by taking into account abdominal obesity in normal-weight men, post-menopausal age in women and regular smoking in both sexes....

  11. Orientation Dependence in Molecular Dynamics Simulations of Shocked Single Crystals

    Germann, Timothy C.; Holian, Brad Lee; Lomdahl, Peter S.; Ravelo, Ramon

    2000-01-01

    We use multimillion-atom molecular dynamics simulations to study shock wave propagation in fcc crystals. As shown recently, shock waves along the direction form intersecting stacking faults by slippage along {111} close-packed planes at sufficiently high shock strengths. We find even more interesting behavior of shocks propagating in other low-index directions: for the case, an elastic precursor separates the shock front from the slipped (plastic) region. Shock waves along the direction generate a leading solitary wave train, followed (at sufficiently high shock speeds) by an elastic precursor, and then a region of complex plastic deformation. (c) 2000 The American Physical Society

  12. Toxic shock syndrome

    Staphylococcal toxic shock syndrome; Toxic shock-like syndrome; TSLS ... Toxic shock syndrome is caused by a toxin produced by some types of staphylococcus bacteria. A similar problem, called toxic shock- ...

  13. Final Report for Project DE-SC0006958: "An Investigation of the Effects of magnetic Fields and Collisionality on Shock Formation in Radiatively Cooled Plasma Flows"

    Bott-Suzuki, Simon

    2014-11-05

    We have developed a new experimental platform to study bow-shock formation in plasma flows generated using an inverse wire array z-pinch. We have made significant progress on the analysis of both hydrodynamic and magnetized shocks using this system. The hydrodynamic experiments show formation of a well-defined Mach cone, and highly localized shock strong associated with radiative losses and rapidly cooling over the shock. Magnetized shocks show that the balance of magnetic and ram pressures dominate the evolution of the shock region, generating a low plasma beta void around the target. Manuscripts are in preparation for publication on both these topics. We have also published the development of a novel diagnostic method which allow recovery of interferometry and self-emission data along the same line of sight. Finally, we have carried out work to integrate a kinetic routine with the 3D MHD code Gorgon, however it remains to complete this process. Both undergraduate and graduate students have been involved in both the experimental work and publications.

  14. Dewey Decimal Classification Online Project: Evaluation of a Library Schedule and Index Integrated into the Subject Searching Capabilities of an Online Catalog. Final Report.

    Markey, Karen; Demeyer, Anh N.

    In this research project, subject terms from the Dewey Decimal Classification (DDC) Schedules and Relative Index were incorporated into an online catalog as searcher's tools for subject access, browsing, and display. Four features of the DDC were employed to help searchers browse for and match their own subject terms with the online catalog's…

  15. Shock Waves

    Jiang, Z

    2005-01-01

    The International Symposium on Shock Waves (ISSW) is a well established series of conferences held every two years in a different location. A unique feature of the ISSW is the emphasis on bridging the gap between physicists and engineers working in fields as different as gas dynamics, fluid mechanics and materials sciences. The main results presented at these meetings constitute valuable proceedings that offer anyone working in this field an authoritative and comprehensive source of reference.

  16. SAT-WIND project. Final report[Winds from satellites for offshore and coastal wind energy mapping and wind-indexing

    Hasager, C.B.; Astrup, P.; Nielsen, M. (and others)

    2007-04-15

    The SAT-WIND project 'Winds from satellites for offshore and coastal wind energy mapping and wind-indexing' was a research project funded by STVF/DSF in the years 2003 to 2006 (Sagsnr. 2058-03-0006). The goal of the project was to verify the applicability of satellite wind maps derived from passive microwave, altimeter, scatterometer and imaging Synthetic Aperture Radar (SAR) technologies for wind energy tools for wind resources and wind-indexing. The study area was the Danish Seas including the North Sea, interior seas and the Baltic Sea. The report describes technical details on the satellite data sources including: 1) passive microwave (SSM/I, AMSR-E), 2) passive microwave polarimetric (WindSat), 3) scatterometer (ERS, QuikSCAT, Midori-2 and NSCAT), 4) altimeter (ERS, Topex, Poseidon, GFO-1, Jason-1), 5) SAR (ERS, Envisat). The SAR wind maps were treated in S-WAsP developed by Risoe National Laboratory in cooperation with GRAS A/S in the innovative project SAT-WIND-SMV (Sagsnr. 2104-05-0084) in the years 2005 and 2006 in parallel with SAT-WIND. The results from the SAT-WIND project are presented. These include ocean wind statistics, offshore wind resource estimates and comparison results for wind-indexing. (au)

  17. SAT-WIND project. Final report[Winds from satellites for offshore and coastal wind energy mapping and wind-indexing

    Hasager, C B; Astrup, P; Nielsen, M [and others

    2007-04-15

    The SAT-WIND project 'Winds from satellites for offshore and coastal wind energy mapping and wind-indexing' was a research project funded by STVF/DSF in the years 2003 to 2006 (Sagsnr. 2058-03-0006). The goal of the project was to verify the applicability of satellite wind maps derived from passive microwave, altimeter, scatterometer and imaging Synthetic Aperture Radar (SAR) technologies for wind energy tools for wind resources and wind-indexing. The study area was the Danish Seas including the North Sea, interior seas and the Baltic Sea. The report describes technical details on the satellite data sources including: 1) passive microwave (SSM/I, AMSR-E), 2) passive microwave polarimetric (WindSat), 3) scatterometer (ERS, QuikSCAT, Midori-2 and NSCAT), 4) altimeter (ERS, Topex, Poseidon, GFO-1, Jason-1), 5) SAR (ERS, Envisat). The SAR wind maps were treated in S-WAsP developed by Risoe National Laboratory in cooperation with GRAS A/S in the innovative project SAT-WIND-SMV (Sagsnr. 2104-05-0084) in the years 2005 and 2006 in parallel with SAT-WIND. The results from the SAT-WIND project are presented. These include ocean wind statistics, offshore wind resource estimates and comparison results for wind-indexing. (au)

  18. Shock parameter calculations at weak interplanetary shock waves

    J. M. Gloag

    2005-02-01

    Full Text Available A large set of interplanetary shock waves observed using the Ulysses spacecraft is analysed in order to determine their local parameters. For the first time a detailed analysis is extended to the thermodynamic properties of a large number of events. The intention is to relate the shock parameters to the requirements set by MHD shock theory. A uniform approach is adopted in the selection of up and downstream regions for this analysis and applied to all the shock waves. Initially, the general case of a 3 component adiabatic plasma is considered. However, the calculation of magnetosonic and Alfvénic Mach numbers and the ratio of downstream to upstream entropy produce some unexpected results. In some cases there is no clear increase in entropy across the shock and also the magnetosonic Mach number can be less than 1. It is found that a more discerning use of data along with an empirical value for the polytropic index can raise the distribution of downstream to upstream entropy ratios to a more acceptable level. However, it is also realised that many of these shocks are at the very weakest end of the spectrum and associated phenomena may also contribute to the explanation of these results.

  19. Changes in body mass index and incidence of diabetes: A longitudinal study of Alberta's Tomorrow Project Cohort.

    Ye, Ming; Robson, Paula J; Eurich, Dean T; Vena, Jennifer E; Xu, Jian-Yi; Johnson, Jeffrey A

    2018-01-01

    Although obesity is a known risk factor for diabetes, the impact of body mass index (BMI) changes over time, especially BMI reduction, on diabetes development is less than clear. The objective of this study is to characterize the association between BMI changes over time and incidence of diabetes in a cohort of adults in Alberta. From 2000 to 2008, Alberta's Tomorrow Project (ATP) enrolled participants aged 35-69 to a population-based prospective cohort study. BMI was calculated from self-reported height and weight; change in BMI (∆BMI) was calculated as the difference between baseline and follow-up measurements. Diabetes cases were identified using the Canadian National Diabetes Surveillance System algorithm applied to linked administrative data (2000-2015). Multivariable Cox regression was used to examine the association between ∆BMI and incidence of diabetes. In a subset of the ATP cohort (n=19,164), 1168 incident cases of diabetes were identified during 198,853person-years of follow-up. Overall, BMI increase was associated with increased risk and BMI reduction was associated with reduced risk of diabetes. Particularly, compared to minimal BMI change (±5%), moderate (5%-10%) reduction in BMI was associated with 34% (95% CI: 12%-51%) reduction in risk of diabetes in participants with obesity; whereas 10% or greater increase in BMI was associated with an increased risk of diabetes of 64% or more in participants with overweight and obesity; in participants with normal and underweight, BMI changes was not apparently associated with risk of diabetes. Public health programs promoting weight loss, even at a moderate extent, would reduce risk of diabetes. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. 0-6683 : develop a pavement project evaluation index to support the 4-year pavement management plan.

    2013-08-01

    A pavement management plan (PMP) identifies : candidate maintenance and rehabilitation (M&R) : projects for a particular roadway network over a : multi-year planning period. The PMP is a living : document because projects are reevaluated and : reprio...

  1. The value of the renal resistive index in the measurement of renal perfusion before and after extracorporal shock wave lithotripsy in correlation to the scintigraphy, to the magnetic resonance perfusion imaging and to big-endothelin values

    Palwein-Prettner, L.

    1999-07-01

    Purpose: the goal of this study was to evaluate effects of extracorporeal shock wave lithotripsy (ESWL) on the renal perfusion using the resistive index (RI), perfusion scintigraphy, magnetic resonance (MR) perfusion imaging and plasma big-endothelin (big-ET-1) values. Method/materials: In 21 patients divided in 3 age-groups the RI was measured before and 1,3,6 and 24 hours after ESWL. Big-ET-1, a potent vasoconstrictor peptid was correlated with the RI values. The RI and Big-ET-1 results was compared to the results of the MR perfusion imaging and the scintigraphy, the gold-standard method. Results: The RI of the treated kidneys increased significantly from 0,64±0,05 to 0,72±0,08 after the ESWL (p<0,001) and in the untreated kidneys from 0,63±0,05 to 0,68±0,09 (p=0,003). The hightest age group shows the most significant increase. The Big-ET-values also increased only in this age group significantly from 0,78±0,24 fmol/l to 1,58±0,52 fmol/l. In the scintigraphy the decrease of the renal plasma flow (RPF) in this age group was most significant. The MR perfusion Imaging shows in all age groups significant decrease (p<0,001). Conclusion: we conclude that the ESWL causes considerable renal parenchymal damage only in the elderly patients. The following changes in renal perfusion were measured very sensitively with the RI which had a good correlation to the results of the perfusion scintigraphy and the MR perfusion imaging. Further studies with larger series have to evaluate these results. (author)

  2. Computations of slowly moving shocks

    Karni, S.; Canic, S.

    1997-01-01

    Computations of slowly moving shocks by shock capturing schemes may generate oscillations are generated already by first-order schemes, but become more pronounced in higher-order schemes which seem to exhibit different behaviors: (i) the first-order upwind (UW) scheme which generates strong oscillations and (ii) the Lax-Friedrichs scheme which appears not to generate any disturbances at all. A key observation is that in the UW case, the numerical viscosity in the shock family vanishes inside the slow shock layer. Simple scaling arguments show the third-order effects on the solution may no longer be neglected. We derive the third-order modified equation for the UW scheme and regard the oscillatory solution as a traveling wave solution of the parabolic modified equation for the perturbation. We then look at the governing equation for the perturbation, which points to a plausible mechanism by which postshock oscillations are generated. It contains a third-order source term that becomes significant inside the shock layer, and a nonlinear coupling term which projects the perturbation on all characteristic fields, including those not associated with the shock family. 5 refs., 8 figs

  3. Browse Title Index

    Items 201 - 250 of 661 ... Journal Home > Advanced Search > Browse Title Index. Log in or Register to get access to full text downloads. .... A El-Mahdy, B Bolduc, J Upadhyay, R Shoukr, A Khoury. Vol 19, No 1 (2013), Factors affecting lower calyceal stone clearance after Extracorporeal shock wave lithotripsy, Abstract PDF.

  4. Relationships between oil price shocks and stock market: An empirical analysis from China

    Cong Ronggang; Wei Yiming; Jiao Jianlin; Fan Ying

    2008-01-01

    This paper investigates the interactive relationships between oil price shocks and Chinese stock market using multivariate vector auto-regression. Oil price shocks do not show statistically significant impact on the real stock returns of most Chinese stock market indices, except for manufacturing index and some oil companies. Some 'important' oil price shocks depress oil company stock prices. Increase in oil volatility may increase the speculations in mining index and petrochemicals index, which raise their stock returns. Both the world oil price shocks and China oil price shocks can explain much more than interest rates for manufacturing index

  5. Glycemic load, glycemic index, bread and incidence of overweight/obesity in a Mediterranean cohort: the SUN project.

    de la Fuente-Arrillaga, Carmen; Martinez-Gonzalez, Miguel Angel; Zazpe, Itziar; Vazquez-Ruiz, Zenaida; Benito-Corchon, Silvia; Bes-Rastrollo, Maira

    2014-10-22

    To evaluate prospectively the relationship between white, or whole grain bread, and glycemic index, or glycemic load from diet and weight change in a Mediterranean cohort. We followed-up 9 267 Spanish university graduates for a mean period of 5 years. Dietary habits at baseline were assessed using a semi-quantitative 136-item food-frequency questionnaire. Average yearly weight change was evaluated according to quintiles of baseline glycemic index, glycemic load, and categories of bread consumption. We also assessed the association between bread consumption, glycemic index, or glycemic load, and the incidence of overweight/obesity. White bread and whole-grain bread were not associated with higher weight gain. No association between glycemic index, glycemic load and weight change was found.White bread consumption was directly associated with a higher risk of becoming overweight/obese (adjusted OR (≥2 portions/day) versus (≤1 portion/week): 1.40; 95% CI: 1.08-1.81; p for trend: 0.008). However, no statistically significant association was observed between whole-grain bread, glycemic index or glycemic load and overweight/obesity. Consumption of white bread (≥2 portions/day) showed a significant direct association with the risk of becoming overweight/obese.

  6. Indexed bibliography on tritium: its sources and projections, behavior, measurement and monitoring techniques, health physics aspects, and waste management

    Dixon, M.N.; Holoway, C.F.; Houser, B.L.; Jacobs, D.G.

    1975-08-01

    References are presented to the world literature on sources of tritium in the environment, the migration of tritium in the environment and uptake by biological materials, monitoring methods, health aspects, and radioactive waste management. Subject, author, and permuted title indexes are included. (U.S.)

  7. Associations of key diet-quality indexes with mortality in the Multiethnic Cohort: the Dietary Patterns Methods Project.

    Harmon, Brook E; Boushey, Carol J; Shvetsov, Yurii B; Ettienne, Reynolette; Reedy, Jill; Wilkens, Lynne R; Le Marchand, Loic; Henderson, Brian E; Kolonel, Laurence N

    2015-03-01

    Healthy dietary patterns have been linked positively with health and longevity. However, prospective studies in diverse populations in the United States addressing dietary patterns and mortality are limited. We assessed the ability of the following 4 diet-quality indexes [the Healthy Eating Index-2010 (HEI-2010), the Alternative HEI-2010 (AHEI-2010), the alternate Mediterranean diet score (aMED), and the Dietary Approaches to Stop Hypertension (DASH)] to predict the reduction in risk of mortality from all causes, cardiovascular disease (CVD), and cancer. White, African American, Native Hawaiian, Japanese American, and Latino adults (n = 215,782) from the Multiethnic Cohort completed a quantitative food-frequency questionnaire. Scores for each dietary index were computed and divided into quintiles for men and women. Mortality was documented over 13-18 y of follow-up. HRs and 95% CIs were computed by using adjusted Cox models. High HEI-2010, AHEI-2010, aMED, and DASH scores were all inversely associated with risk of mortality from all causes, CVD, and cancer in both men and women (P-trend dietary pattern that achieves a high diet-quality index score is associated with lower risk of mortality from all causes, CVD, and cancer in adult men and women. © 2015 American Society for Nutrition.

  8. Collisionless electrostatic shocks

    Andersen, H.K.; Andersen, S.A.; Jensen, Vagn Orla

    1970-01-01

    An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth......An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth...

  9. Micro-Raman spectroscopy of plagioclase and maskelynite in Martian meteorites: Evidence of progressive shock metamorphism

    Fritz,Jorg; Greshake,Ansgar; Stoffler,Dieter

    2005-01-01

    We present the first systematic Micro-Raman spectroscopic investigation of plagioclase of different degree of shock metamorphism in Martian meteorites. The equilibrium shock pressure of all plagioclase phases of seventeen unpaired Martian meteorites was determined by measuring the shock-induced reduction of the refractive index. Systematic variations in the recorded Raman spectra of the plagioclase phases correlate with increasing shock pressure. In general, the shock induced deformation of t...

  10. INDEXING AND INDEX FUNDS

    HAKAN SARITAŞ

    2013-06-01

    Full Text Available Proponents of the efficient market hypothesis believe that active portfolio management is largely wasted effort and unlikely to justify the expenses incurred. Therefore, they advocate a passive investment strategy that makes no attempt to outsmart the market. One common strategy for passive management is indexing where a fund is designed to replicate the performance of a broad-based index of stocks and bonds. Traditionally, indexing was used by institutional investors, but today, the use of index funds proliferated among individual investors. Over the years, both international and domestic index funds have disproportionately outperformed the market more than the actively managed funds have.

  11. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    Mostert, W.; Pullin, D. I.; Samtaney, Ravi; Wheatley, V.

    2016-01-01

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  12. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    Mostert, W.

    2016-12-12

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  13. Relationships between oil price shocks and stock market: An empirical analysis from China

    Cong, Ronggang; Wei, Yi-Ming; Jiao, Jian-Ling

    2008-01-01

    This paper investigates the interactive relationships between oil price shocks and Chinese stock market using multivariate vector auto-regression. Oil price shocks do not show statistically significant impact on the real stock returns of most Chinese stock market indices, except for manufacturing...... index and some oil companies. Some “important” oil price shocks depress oil company stock prices. Increase in oil volatility may increase the speculations in mining index and petrochemicals index, which raise their stock returns. Both the world oil price shocks and China oil price shocks can explain...

  14. Converging shocks in elastic-plastic solids.

    Ortega, A López; Lombardini, M; Hill, D J

    2011-11-01

    We present an approximate description of the behavior of an elastic-plastic material processed by a cylindrically or spherically symmetric converging shock, following Whitham's shock dynamics theory. Originally applied with success to various gas dynamics problems, this theory is presently derived for solid media, in both elastic and plastic regimes. The exact solutions of the shock dynamics equations obtained reproduce well the results obtained by high-resolution numerical simulations. The examined constitutive laws share a compressible neo-Hookean structure for the internal energy e=e(s)(I(1))+e(h)(ρ,ς), where e(s) accounts for shear through the first invariant of the Cauchy-Green tensor, and e(h) represents the hydrostatic contribution as a function of the density ρ and entropy ς. In the strong-shock limit, reached as the shock approaches the axis or origin r=0, we show that compression effects are dominant over shear deformations. For an isothermal constitutive law, i.e., e(h)=e(h)(ρ), with a power-law dependence e(h) is proportional to ρ(α), shock dynamics predicts that for a converging shock located at r=R(t) at time t, the Mach number increases as M is proportional to [log(1/R)](α), independently of the space index s, where s=2 in cylindrical geometry and 3 in spherical geometry. An alternative isothermal constitutive law with p(ρ) of the arctanh type, which enforces a finite density in the strong-shock limit, leads to M is proportional to R(-(s-1)) for strong shocks. A nonisothermal constitutive law, whose hydrostatic part e(h) is that of an ideal gas, is also tested, recovering the strong-shock limit M is proportional to R(-(s-1)/n(γ)) originally derived by Whitham for perfect gases, where γ is inherently related to the maximum compression ratio that the material can reach, (γ+1)/(γ-1). From these strong-shock limits, we also estimate analytically the density, radial velocity, pressure, and sound speed immediately behind the shock. While the

  15. Estimating average shock pressures recorded by impactite samples based on universal stage investigations of planar deformation features in quartz - Sources of error and recommendations

    Holm-Alwmark, S.; Ferrière, L.; Alwmark, C.; Poelchau, M. H.

    2018-01-01

    Planar deformation features (PDFs) in quartz are the most widely used indicator of shock metamorphism in terrestrial rocks. They can also be used for estimating average shock pressures that quartz-bearing rocks have been subjected to. Here we report on a number of observations and problems that we have encountered when performing universal stage measurements and crystallographically indexing of PDF orientations in quartz. These include a comparison between manual and automated methods of indexing PDFs, an evaluation of the new stereographic projection template, and observations regarding the PDF statistics related to the c-axis position and rhombohedral plane symmetry. We further discuss the implications that our findings have for shock barometry studies. Our study shows that the currently used stereographic projection template for indexing PDFs in quartz might induce an overestimation of rhombohedral planes with low Miller-Bravais indices. We suggest, based on a comparison of different shock barometry methods, that a unified method of assigning shock pressures to samples based on PDFs in quartz is necessary to allow comparison of data sets. This method needs to take into account not only the average number of PDF sets/grain but also the number of high Miller-Bravais index planes, both of which are important factors according to our study. Finally, we present a suggestion for such a method (which is valid for nonporous quartz-bearing rock types), which consists of assigning quartz grains into types (A-E) based on the PDF orientation pattern, and then calculation of a mean shock pressure for each sample.

  16. Miniature shock tube for laser driven shocks.

    Busquet, Michel; Barroso, Patrice; Melse, Thierry; Bauduin, Daniel

    2010-02-01

    We describe in this paper the design of a miniature shock tube (smaller than 1 cm(3)) that can be placed in a vacuum vessel and allows transverse optical probing and longitudinal backside extreme ultraviolet emission spectroscopy in the 100-500 A range. Typical application is the study of laser launched radiative shocks, in the framework of what is called "laboratory astrophysics."

  17. Are Credit Shocks Supply or Demand Shocks?

    Bijapur, Mohan

    2013-01-01

    This paper provides new insights into the relationship between the supply of credit and the macroeconomy. We present evidence that credit shocks constitute shocks to aggregate supply in that they have a permanent effect on output and cause inflation to rise in the short term. Our results also suggest that the effects on aggregate supply have grown stronger in recent decades.

  18. Shock absorbing structure

    Kojima, Naoki; Matsushita, Kazuo.

    1992-01-01

    Small pieces of shock absorbers are filled in a space of a shock absorbing vessel which is divided into a plurality of sections by partitioning members. These sections function to prevent excess deformation or replacement of the fillers upon occurrence of falling accident. Since the shock absorbing small pieces in the shock absorbing vessel are filled irregularly, shock absorbing characteristics such as compression strength is not varied depending on the direction, but they exhibit excellent shock absorbing performance. They surely absorb shocks exerted on a transportation vessel upon falling or the like. If existing artificial fillers such as pole rings made of metal or ceramic and cut pieces such as alumium extrusion molding products are used as the shock absorbing pieces, they have excellent fire-proofness and cold resistance since the small pieces are inflammable and do not contain water. (T.M.)

  19. Melting under shock compression

    Bennett, B.I.

    1980-10-01

    A simple model, using experimentally measured shock and particle velocities, is applied to the Lindemann melting formula to predict the density, temperature, and pressure at which a material will melt when shocked from room temperature and zero pressure initial conditions

  20. Biomass shock pretreatment

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  1. Relativistic Shock Acceleration

    Duffy, P.; Downes, T.P.; Gallant, Y.A.; Kirk, J.G.

    1999-01-01

    In this paper we briefly review the basic theory of shock waves in relativistic hydrodynamics and magneto-hydrodynamics, emphasising some astrophysically interesting cases. We then present an overview of the theory of particle acceleration at such shocks describing the methods used to calculate the spectral indices of energetic particles. Recent results on acceleration at ultra-relativistic shocks are discussed. (author)

  2. PROJECT HANFORD MANAGEMENT CONTRACT (PHMC) PERFORMANCE REPORT 05/2004 (WWW.HANFORD.GOV/EMPR.INDEX.CFM)

    PIELSTICK, R.M.

    2004-01-01

    This report is the monthly performance summary of the Central Plateau Contractors. FH work scope responsibilities are described, and other contractor/RL-managed work is excluded. Section A, Overview, provides a summary of the cost, schedule, and technical performance described in this report. It summarizes performance for the period covered, highlights areas worthy of management attention, and provides key performance activities as extracted from the contractor baseline. Subsequent sections of this report provide detailed performance data relative to contract sections (e.g., Project Hanford Cleanup Work Summary, Waste and Spent Nuclear Fuel Management Operations, Infrastructure and Hanford Site Services, and other Work Scope). All information is as of the end of May 2004 unless otherwise noted

  3. EXPERIMENTAL STUDY OF SHOCK WAVE DYNAMICS IN MAGNETIZED PLASMAS

    Podder, Nirmol K.

    2009-01-01

    In this four-year project (including one-year extension), the project director and his research team built a shock-wave-plasma apparatus to study shock wave dynamics in glow discharge plasmas in nitrogen and argon at medium pressure (1-20 Torr), carried out various plasma and shock diagnostics and measurements that lead to increased understanding of the shock wave acceleration phenomena in plasmas. The measurements clearly show that in the steady-state dc glow discharge plasma, at fixed gas pressure the shock wave velocity increases, its amplitude decreases, and the shock wave disperses non-linearly as a function of the plasma current. In the pulsed discharge plasma, at fixed gas pressure the shock wave dispersion width and velocity increase as a function of the delay between the switch-on of the plasma and shock-launch. In the afterglow plasma, at fixed gas pressure the shock wave dispersion width and velocity decrease as a function of the delay between the plasma switch-off and shock-launch. These changes are found to be opposite and reversing towards the room temperature value which is the initial condition for plasma ignition case. The observed shock wave properties in both igniting and afterglow plasmas correlate well with the inferred temperature changes in the two plasmas

  4. Alfven shock trains

    Malkov, M.A.; Kennel, C.F.; Wu, C.C.; Pellat, R.; Shapiro, V.D.

    1991-01-01

    The Cohen--Kulsrud--Burgers equation (CKB) is used to consider the nonlinear evolution of resistive, quasiparallel Alfven waves subject to a long-wavelength, plane-polarized, monochromatic instability. The instability saturates by nonlinear steepening, which proceeds until the periodic waveform develops an interior scale length comparable to the dissipation length; a fast or an intermediate shock then forms. The result is a periodic train of Alfven shocks of one or the other type. For propagation strictly parallel to the magnetic field, there will be two shocks per instability wavelength. Numerical integration of the time-dependent CKB equation shows that an initial, small-amplitude growing wave asymptotes to a stable, periodic stationary wave whose analytic solution specifies how the type of shock embedded in the shock train, and the amplitude and speed of the shock train, depend on the strength and phase of the instability. Waveforms observed upstream of the Earth's bowshock and cometary shocks resemble those calculated here

  5. A Project to Develop an Index of PC 3,4,5 Geomagnetic Pulsations and to Study Their control by Solar Wind Parameters.

    1983-04-01

    source of Pc 3,4 pulsations in foreshock signals, shock pulsations, and magnetosheath turbulence, and several groups are actively exanining this...link between wavetrains in the sheath and Pc 3,4 has ever been proved, however, althugh the possibility that foreshock waves, which resemble pulsations...shock and foreshock reglons con- variations in wave correlation observable in the stitute the essential tool for distingi.shing running 12-second

  6. Projectables

    Rasmussen, Troels A.; Merritt, Timothy R.

    2017-01-01

    CNC cutting machines have become essential tools for designers and architects enabling rapid prototyping, model-building and production of high quality components. Designers often cut from new materials, discarding the irregularly shaped remains. We introduce ProjecTables, a visual augmented...... reality system for interactive packing of model parts onto sheet materials. ProjecTables enables designers to (re)use scrap materials for CNC cutting that would have been previously thrown away, at the same time supporting aesthetic choices related to wood grain, avoiding surface blemishes, and other...... relevant material properties. We conducted evaluations of ProjecTables with design students from Aarhus School of Architecture, demonstrating that participants could quickly and easily place and orient model parts reducing material waste. Contextual interviews and ideation sessions led to a deeper...

  7. Application of Underwater Shock Wave Focusing to the Development of Extracorporeal Shock Wave Lithotripsy

    Takayama, Kazuyoshi

    1993-05-01

    This paper describes a summary of a research project for the development of extracorporeal shock wave lithotripsy (ESWL), which has been carried out, under close collaboration between the Shock Wave Research Center of Tohoku University and the School of Medicine, Tohoku University. The ESWL is a noninvasive clinical treatment of disintegrating human calculi and one of the most peaceful applications of shock waves. Underwater spherical shock waves were generated by explosion of microexplosives. Characteristics of the underwater shock waves and of ultrasound focusing were studied by means of holographic interferometric flow visualization and polyvinyliden-difluoride (PVDF) pressure transducers. These focused pressures, when applied to clinical treatments, could effectively and noninvasively disintegrate urinary tract stones or gallbladder stones. However, despite clincal success, tissue damage occurs during ESWL treatments, and the possible mechanism of tissue damage is briefly described.

  8. System Shock: The Archetype of Operational Shock

    2017-05-25

    the battle space. They can also facilitate a much greater understanding of the variables involved in each party’s decision - making process. However...system shock nests within current US Army Unified Land Operations doctrine. In order to test the utility of system shock theory to Gray Zone...23 Neil E. Harrison, “Thinking about the World We Make ” in Chaos Theory in the Social Sciences: Foundations and Applications

  9. Comparative review of bow shocks and magnetopauses

    Lepping, R.P.

    1984-04-01

    Bow shock and magnetopauses formation is discussed. Plasma and magnetic field environments of all the planets from Mercury to Saturn were measured. It was found that all the planets have bow shocks and almost all have a magnetopause. Venus is the only planet with no measurable intrinsic magnetic field and the solar wind interacts directly with Venus ionosphere. The bow shock characteristics depend on the changing solar wind conditions. The shape of a magnetopause or any obstacle to flow depends on the three dimensional pressure profile that it presents to the solar wind. Jupiter is unusual because of the considerable amount of plasma which is contained in its magnetosphere. Magentopause boundaries in ecliptic plane projection are modelled by segments of ellipses, matched to straight lines for the magnetotool boundaries or parabolas. Specific properties of known planetary bow shocks and magnetopauses are reviewed

  10. Holographic interferometric observation of shock wave focusing to extracorporeal shock wave lithotripsy

    Takayama, Kazuyoshi; Obara, Tetsuro; Onodera, Osamu

    1991-04-01

    Underwater shock wave focusing is successfully applied to disintegrate and remove kidney stones or gallbladder stones without using surgical operations. This treatment is one of the most peaceful applications ofshock waves and is named as the Extracorporeal Shock Wave Lithotripsy. Ajoint research project is going on between the Institute ofFluid Science, Tohoku University and the School ofMedicine, Tohoku University. The paper describes a result of the fundamental research on the underwater shock wave focusing applied to the ESWL. Quantitatively to visualize the underwater shock waves, various optical flow visualization techniques were successfully used such as holographic interferometry, and shadowgraphs combined with Ima-Con high speed camera. Double exposure holographic interferometric observation revealed the mechanism of generation, propagation and focusing of underwater shock waves. The result of the present research was already used to manufacture a prototype machine and it has already been applied successfully to ESWL crinical treatments. However, despite of success in the clinical treatments, important fundamental questions still remain unsolved, i.e., effects of underwater shock wave focusing on tissue damage during the treatment. Model experiments were conducted to clarify mechanism of the tissue damage associated with the ESWL. Shock-bubble interactions were found responsible to the tissue damage during the ESWL treatment. In order to interprete experimental findings and to predict shock wave behavior and high pressures, a numerical simulation was carried. The numerical results agreed with the experiments.

  11. Shock dynamics of weak imploding cylindrical and spherical shock waves with non-ideal gas effects

    Anand, R K

    2013-01-01

    The author (Anand 2012 Astrophys. Space Sci. 342 377–88) recently obtained jump relations across a shock front in non-ideal gas flow taking into consideration the equation of state for a non-ideal gas as given by Landau and Lifshitz. In this paper an analytical solution for one-dimensional adiabatic flow behind weak converging shock waves propagating in a non-ideal gas is obtained by using Whitham's (1974 Linear and Nonlinear Waves (New York: Wiley)) geometrical shock dynamics approach. The effects of an increase in (i) the propagation distance from the centre of convergence, (ii) the non-idealness parameter and (iii) the adiabatic index of the gas, on the shock velocity, pressure, density, particle velocity, adiabatic compressibility and the change in entropy across the shock front, are analyzed. The results provided a clear picture of whether and how the non-idealness parameter and the adiabatic index affect the flow field behind the imploding shock front. (paper)

  12. Studies on laser–plasma interaction physics for shock ignition

    Maheut, Y.; Batani, D.; Nicolai, Ph.; Antonelli, L.; Krouský, Eduard

    2015-01-01

    Roč. 170, č. 4 (2015), s. 325-336 ISSN 1042-0150 EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE Institutional support: RVO:68378271 Keywords : shock ignition * plasma * hot electrons * shocks * fusion Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 0.472, year: 2015

  13. Biological effects of tandem shock waves demonstrated on magnetic resonance

    Beneš, J.; Zeman, J.; Poučková, P.; Zadinová, M.; Šunka, Pavel; Lukeš, Petr

    Roč. 113, č. 6 ( 2012 ), s. 335-338 ISSN 0006-9248 R&D Projects: GA ČR GA202/09/1151 Institutional research plan: CEZ:AV0Z20430508 Keywords : electrical discharges in water * focused shock waves * cavitations * tandem shock waves Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.472, year: 2012

  14. Particle acceleration at shocks in the inner heliosphere

    Parker, Linda Neergaard

    This dissertation describes a study of particle acceleration at shocks via the diffusive shock acceleration mechanism. Results for particle acceleration at both quasi-parallel and quasi-perpendicular shocks are presented to address the question of whether there are sufficient particles in the solar wind thermal core, modeled as either a Maxwellian or kappa- distribution, to account for the observed accelerated spectrum. Results of accelerating the theoretical upstream distribution are compared to energetic observations at 1 AU. It is shown that the particle distribution in the solar wind thermal core is sufficient to explain the accelerated particle spectrum downstream of the shock, although the shape of the downstream distribution in some cases does not follow completely the theory of diffusive shock acceleration, indicating possible additional processes at work in the shock for these cases. Results show good to excellent agreement between the theoretical and observed spectral index for one third to one half of both quasi-parallel and quasi-perpendicular shocks studied herein. Coronal mass ejections occurring during periods of high solar activity surrounding solar maximum can produce shocks in excess of 3-8 shocks per day. During solar minimum, diffusive shock acceleration at shocks can generally be understood on the basis of single independent shocks and no other shock necessarily influences the diffusive shock acceleration mechanism. In this sense, diffusive shock acceleration during solar minimum may be regarded as Markovian. By contrast, diffusive shock acceleration of particles at periods of high solar activity (e.g. solar maximum) see frequent, closely spaced shocks that include the effects of particle acceleration at preceding and following shocks. Therefore, diffusive shock acceleration of particles at solar maximum cannot be modeled on the basis of diffusive shock acceleration as a single, independent shock and the process is essentially non-Markovian. A

  15. Climate conditions and drought assessment with the Palmer Drought Severity Index in Iran: evaluation of CORDEX South Asia climate projections (2070-2099)

    Senatore, Alfonso; Hejabi, Somayeh; Mendicino, Giuseppe; Bazrafshan, Javad; Irannejad, Parviz

    2018-03-01

    Climate change projections were evaluated over both the whole Iran and six zones having different precipitation regimes considering the CORDEX South Asia dataset, for assessing space-time distribution of drought occurrences in the future period 2070-2099 under RCP4.5 scenario. Initially, the performances of eight available CORDEX South Asia Regional Climate Models (RCMs) were assessed for the baseline period 1970-2005 through the GPCC v.7 precipitation dataset and the CFSR temperature dataset, which were previously selected as the most reliable within a set of five global datasets compared to 41 available synoptic stations. Though the CCLM RCM driven by the MPI-ESM-LR General Circulation Model is in general the most suitable for temperature and, together with the REMO 2009 RCM also driven by MPI-ESM-LR, for precipitation, their performances do not overwhelm other models for every season and zone in which Iranian territory was divided according to a principal component analysis approach. Hence, a weighting approach was tested and adopted to take into account useful information from every RCM in each of the six zones. The models resulting more reliable compared to current climate show a strong precipitation decrease. Weighted average predicts an overall yearly precipitation decrease of about 20%. Temperature projections provide a mean annual increase of 2.4 °C. Future drought scenarios were depicted by means of the self-calibrating version of the Palmer drought severity index (SC-PDSI) model. Weighted average predicts a sharp drying that can be configured as a real shift in mean climate conditions, drastically affecting water resources of the country.

  16. Hydraulic shock absorbers

    Thatcher, G.; Davidson, D. F.

    1984-01-01

    A hydraulic shock absorber of the dash pot kind for use with electrically conducting liquid such as sodium, has magnet means for electro magnetically braking a stream of liquid discharged from the cylinder. The shock absorber finds use in a liquid metal cooled nuclear reactor for arresting control rods

  17. Our Favorite Film Shocks

    Willerslev, Rane; Suhr, Christian

    2014-01-01

    The modern medium of film has long been hailed for its capacity for producing shocks of an entertaining, thought-provoking, or even politically emancipative nature. But what is a shock, how and when does it occur, how long does it last, and are there particular techniques for producing cinematic...

  18. Climate shocks and conflict

    Papaioannou, Kostadis J.

    2016-01-01

    This paper offers a historical micro-level analysis of the impact of climate shocks on the incidence of civil conflict in colonial Nigeria (1912-1945). Primary historical sources on court cases, prisoners and homicides are used to capture conflict. To measure climate shocks we use the deviation

  19. Zygosity differences in height and body mass index of twins from infancy to old age: A study of the CODATwins project

    Jelenkovic, Aline; Yokoyama, Yoshie; Sund, Reijo; Honda, Chika; Bogl, Leonie H; Aaltonen, Sari; Ji, Fuling; Ning, Feng; Pang, Zengchang; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Burt, S Alexandra; Klump, Kelly L; Medland, Sarah E; Montgomery, Grant W; Kandler, Christian; McAdams, Tom A; Eley, Thalia C; Gregory, Alice M; Saudino, Kimberly J; Dubois, Lise; Boivin, Michel; Tarnoki, Adam D; Tarnoki, David L; Haworth, Claire MA; Plomin, Robert; Öncel, Sevgi Y; Aliev, Fazil; Stazi, Maria A; Fagnani, Corrado; D'Ippolito, Cristina; Craig, Jeffrey M; Saffery, Richard; Siribaddana, Sisira H; Hotopf, Matthew; Sumathipala, Athula; Rijsdijk, Fruhling; Spector, Timothy; Mangino, Massimo; Lachance, Genevieve; Gatz, Margaret; Butler, David A; Bayasgalan, Gombojav; Narandalai, Danshiitsoodol; Freitas, Duarte L; Maia, José Antonio; Harden, K Paige; Tucker-Drob, Elliot M; Kim, Bia; Chong, Youngsook; Hong, Changhee; Shin, Hyun Jung; Christensen, Kaare; Skytthe, Axel; Kyvik, Kirsten O; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth JF; Cozen, Wendy; Hwang, Amie E; Mack, Thomas M; He, Mingguang; Ding, Xiaohu; Chang, Billy; Silberg, Judy L; Eaves, Lindon J; Maes, Hermine H; Cutler, Tessa L; Hopper, John L; Aujard, Kelly; Magnusson, Patrik KE; Pedersen, Nancy L; Aslan, Anna K Dahl; Song, Yun-Mi; Yang, Sarah; Lee, Kayoung; Baker, Laura A; Tuvblad, Catherine; Bjerregaard-Andersen, Morten; Beck-Nielsen, Henning; Sodemann, Morten; Heikkilä, Kauko; Tan, Qihua; Zhang, Dongfeng; Swan, Gary E; Krasnow, Ruth; Jang, Kerry L; Knafo-Noam, Ariel; Mankuta, David; Abramson, Lior; Lichtenstein, Paul; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Tynelius, Per; Duncan, Glen E; Buchwald, Dedra; Corley, Robin P; Huibregtse, Brooke M; Nelson, Tracy L; Whitfield, Keith E; Franz, Carol E; Kremen, William S; Lyons, Michael J; Ooki, Syuichi; Brandt, Ingunn; Nilsen, Thomas Sevenius; Inui, Fujio; Watanabe, Mikio; Bartels, Meike; van Beijsterveldt, Toos CEM; Wardle, Jane; Llewellyn, Clare H; Fisher, Abigail; Rebato, Esther; Martin, Nicholas G; Iwatani, Yoshinori; Hayakawa, Kazuo; Sung, Joohon; Harris, Jennifer R; Willemsen, Gonneke; Busjahn, Andreas; Goldberg, Jack H; Rasmussen, Finn; Hur, Yoon-Mi; Boomsma, Dorret I; Sørensen, Thorkild IA; Kaprio, Jaakko; Silventoinen, Karri

    2015-01-01

    A trend towards greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in means and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the CODATwins project and included 842,951 height and BMI measurements from age 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Likewise, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast the variance of BMI was significantly higher in DZ than in MZ twins particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes. PMID:26337138

  20. Counterpropagating Radiative Shock Experiments on the Orion Laser.

    Suzuki-Vidal, F; Clayson, T; Stehlé, C; Swadling, G F; Foster, J M; Skidmore, J; Graham, P; Burdiak, G C; Lebedev, S V; Chaulagain, U; Singh, R L; Gumbrell, E T; Patankar, S; Spindloe, C; Larour, J; Kozlova, M; Rodriguez, R; Gil, J M; Espinosa, G; Velarde, P; Danson, C

    2017-08-04

    We present new experiments to study the formation of radiative shocks and the interaction between two counterpropagating radiative shocks. The experiments are performed at the Orion laser facility, which is used to drive shocks in xenon inside large aspect ratio gas cells. The collision between the two shocks and their respective radiative precursors, combined with the formation of inherently three-dimensional shocks, provides a novel platform particularly suited for the benchmarking of numerical codes. The dynamics of the shocks before and after the collision are investigated using point-projection x-ray backlighting while, simultaneously, the electron density in the radiative precursor was measured via optical laser interferometry. Modeling of the experiments using the 2D radiation hydrodynamic codes nym and petra shows very good agreement with the experimental results.

  1. Capturing Weather-related Shocks In Smallholder Agriculture

    Murray, S.

    2015-12-01

    Rainfed agriculture accounts for 93% of total cultivated area in SSA (FAO, 2002) and smallholder is the predominant form of farm organization (33 million with less than 2 ha, representing 80% of all farms). At the same time, 75% of extreme poor live in rural areas and 90% rely on agriculture. A poor harvest can have significant impact on livelihood and welfare of a household with limited coping mechanisms and little savings.This study aims to shed light on how small farmers are affected by growing conditions in a given season and how well these impacts can be predicted using objective measures derived from time-series of remote-sensing data. We investigate the covariate vs idiosyncratic nature of shocks experienced at the household level, using both community-level and household-level observations. We also test the relative efficiency of different metrics in predicting shocks, acknowledging that both spatial resolution and temporal frequency are likely to be limiting factors in the objective measures. To support this analysis we draw on surveys from the Living Standards Measurement Study Integrated Surveys on Agriculture (LSMS-ISA) project. The LSMS-ISA surveys are georeferenced, multi-topic panel surveys with a strong focus on agriculture, conducted in 7 African countries. We combine the LSMS-ISA data on production and agricultural shocks with objective measures (rainfall deficit/surplus, phenological variables, water requirements satisfaction index) derived from various data sources (CHIRPS, MODIS Land Cover Dynamics, NDVI3g). Objective measures will be considered in both absolute terms as well as deviation from mean in the survey season.

  2. Collisionless shock waves

    Sagdeev, R.Z.; Kennel, C.F.

    1991-01-01

    Collisionless shocks cannot occur naturally on the earth, because nearly all matter here consists of electrically neutral atoms and molecules. In space, however, high temperatures and ultraviolet radiation from hot stars decompose atoms into their constituent nuclei and electrons, producing a soup of electrically charged particles known as a plasma. Plasma physicists proposed that the collective electrical and magnetic properties of plasmas could produce interactions that take the place of collisions and permit shocks to form. In 1964 the theoretical work found its first experimental confirmation. Norman F. Ness and his colleagues at the Goddard Space Flight Center, using data collected from the iMP-1 spacecraft, detected clear signs that a collisionless shock exists where the solar wind encounters the earth's magnetic field. More recent research has demonstrated that collisionless shocks appear in a dazzling array of astronomical settings. For example, shocks have been found in the solar wind upstream (sunward) of all the planet and comets that have been visited by spacecraft. Violent flares on the sun generate shocks that propagate to the far reaches of the solar system; tremendous galactic outbursts create disruptions in the intergalactic medium that are trillions of times larger. In addition, many astrophysicists think that shocks from supernova explosions in our galaxy accelerate cosmic rays, a class of extraordinarily energetic elementary particles and atomic nuclei that rain down on the earth from all directions

  3. Pediatric Toxic Shock Syndrome

    Jennifer Yee

    2017-09-01

    Full Text Available Audience: This scenario was developed to educate emergency medicine residents on the diagnosis and management of a pediatric patient with toxic shock syndrome. The case is also appropriate for teaching of medical students and advanced practice providers, as well as a review of the principles of crisis resource management, teamwork, and communication. Introduction: Toxic shock syndrome is a low-frequency, high-acuity scenario requiring timely identification and aggressive management. If patients suffering from this condition are managed incorrectly, they may progress into multi-organ dysfunction and potentially death. Toxic shock syndrome has been associated with Streptococcus and Staphylococcus aureus (Staph. Approximately half of Staph cases are associated with menstruation, which was first described in the 1970s-1980s and was associated with the use of absorbent tampons.1 Group A Streptococcus may cause complications such as necrotizing fasciitis and gangrenous myositis.2 Pediatric patients may present critically ill from toxic shock syndrome. Providers need to perform a thorough history and physical exam to discern the source of infection. Management requires aggressive care with antibiotics and IV fluids. Objectives: By the end of this simulation session, the learner will be able to: 1 Recognize toxic shock syndrome. 2 Review the importance of a thorough physical exam. 3 Discuss management of toxic shock syndrome, including supportive care and the difference in antibiotic choices for streptococcal and staphylococcal toxic shock syndrome. 4 Appropriately disposition a patient suffering from toxic shock syndrome. 5 Communicate effectively with team members and nursing staff during a resuscitation of a critically ill patient. Method: This session was conducted using high-fidelity simulation, followed by a debriefing session and lecture on toxic shock syndrome.

  4. The Index House

    Reilly, M.A.

    1990-01-01

    This paper reports on the Pennsylvania Radon Research and Demonstration Project. The project involved the monitoring of the Index House for indoor radon, and was one of the earliest programs involving indoor radon contamination. The history of the house, the investigation, and testing and remediation procedures are discussed

  5. Shocks near Jamming

    Gómez, Leopoldo R.; Turner, Ari M.; van Hecke, Martin; Vitelli, Vincenzo

    2012-02-01

    Nonlinear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they jam, these fragile and disordered solids exhibit a vanishing rigidity and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are dynamically compressed and demonstrate that the elementary excitations are strongly nonlinear shocks, rather than ordinary phonons. We capture the full dependence of the shock speed on pressure and impact intensity by a surprisingly simple analytical model.

  6. Mechanical shock absorber

    Vrillon, Bernard.

    1973-01-01

    The mechanical shock absorber described is made of a constant thickness plate pierced with circular holes regularly distributed in such a manner that for all the directions along which the strain is applied during the shock, the same section of the substance forming the plate is achieved. The shock absorber is made in a metal standing up to extensive deformation before breaking, selected from a group comprising mild steels and austenitic stainless steels. This apparatus is used for handling pots of fast neutron reactor fuel elements [fr

  7. Shock formation of HCO+

    Elitzur, M.

    1983-01-01

    It is shown that shocks propagating in dense molecular regions will lead to a decrease in HCO + relative abundance, in agreement with previous results by Iglesias and Silk. The shock enhancement of HCO + detected in the supernova remnant IC 443 by Dickenson et al. is due to enhanced ionization in the shocked material. This is the result of the material penetrating the remnant cavity where it becomes exposed to the trapped cosmic rays. A similar enhancement appears to have been detected by Wootten in W28 and is explained by the same model

  8. Hepatic Shock Differential Diagnosis and Risk Factors: A Review Article.

    Soleimanpour, Hassan; Safari, Saeid; Rahmani, Farzad; Nejabatian, Arezu; Alavian, Seyed Moayed

    2015-10-01

    Liver as an important organ has a vital role in physiological processes in the body. Different causes can disrupt normal function of liver. Factors such as hypo-perfusion, hypoxemia, infections and some others can cause hepatic injury and hepatic shock. Published research resources from 2002 to May 2015 in some databases (PubMed, Scopus, Index Copernicus, DOAJ, EBSCO-CINAHL, Science direct, Cochrane library and Google scholar and Iranian search database like SID and Iranmedex) were investigated for the present study. Different causes can lead to hepatic shock. Most of these causes can be prevented by early resuscitation and treatment of underlying factors. Hepatic shock is detected in ill patients, especially those with hemodynamic disorders. It can be prevented by early treatment of underlying disease. There is no definite treatment for hepatic shock and should be managed conservatively. Hepatic shock in patients can increase the mortality rate.

  9. Shock Isolation Elements Testing for High Input Loadings. Volume II. Foam Shock Isolation Elements.

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*EXPANDED PLASTICS, (*SHOCK(MECHANICS), REDUCTION), TEST METHODS, SHOCK WAVES, STRAIN(MECHANICS), LOADS(FORCES), MATHEMATICAL MODELS, NUCLEAR EXPLOSIONS, HARDENING.

  10. Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age: A Study of the CODATwins Project.

    Jelenkovic, Aline; Yokoyama, Yoshie; Sund, Reijo; Honda, Chika; Bogl, Leonie H; Aaltonen, Sari; Ji, Fuling; Ning, Feng; Pang, Zengchang; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Burt, S Alexandra; Klump, Kelly L; Medland, Sarah E; Montgomery, Grant W; Kandler, Christian; McAdams, Tom A; Eley, Thalia C; Gregory, Alice M; Saudino, Kimberly J; Dubois, Lise; Boivin, Michel; Tarnoki, Adam D; Tarnoki, David L; Haworth, Claire M A; Plomin, Robert; Öncel, Sevgi Y; Aliev, Fazil; Stazi, Maria A; Fagnani, Corrado; D'Ippolito, Cristina; Craig, Jeffrey M; Saffery, Richard; Siribaddana, Sisira H; Hotopf, Matthew; Sumathipala, Athula; Rijsdijk, Fruhling; Spector, Timothy; Mangino, Massimo; Lachance, Genevieve; Gatz, Margaret; Butler, David A; Bayasgalan, Gombojav; Narandalai, Danshiitsoodol; Freitas, Duarte L; Maia, José Antonio; Harden, K Paige; Tucker-Drob, Elliot M; Kim, Bia; Chong, Youngsook; Hong, Changhee; Shin, Hyun Jung; Christensen, Kaare; Skytthe, Axel; Kyvik, Kirsten O; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth J F; Cozen, Wendy; Hwang, Amie E; Mack, Thomas M; He, Mingguang; Ding, Xiaohu; Chang, Billy; Silberg, Judy L; Eaves, Lindon J; Maes, Hermine H; Cutler, Tessa L; Hopper, John L; Aujard, Kelly; Magnusson, Patrik K E; Pedersen, Nancy L; Aslan, Anna K Dahl; Song, Yun-Mi; Yang, Sarah; Lee, Kayoung; Baker, Laura A; Tuvblad, Catherine; Bjerregaard-Andersen, Morten; Beck-Nielsen, Henning; Sodemann, Morten; Heikkilä, Kauko; Tan, Qihua; Zhang, Dongfeng; Swan, Gary E; Krasnow, Ruth; Jang, Kerry L; Knafo-Noam, Ariel; Mankuta, David; Abramson, Lior; Lichtenstein, Paul; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Tynelius, Per; Duncan, Glen E; Buchwald, Dedra; Corley, Robin P; Huibregtse, Brooke M; Nelson, Tracy L; Whitfield, Keith E; Franz, Carol E; Kremen, William S; Lyons, Michael J; Ooki, Syuichi; Brandt, Ingunn; Nilsen, Thomas Sevenius; Inui, Fujio; Watanabe, Mikio; Bartels, Meike; van Beijsterveldt, Toos C E M; Wardle, Jane; Llewellyn, Clare H; Fisher, Abigail; Rebato, Esther; Martin, Nicholas G; Iwatani, Yoshinori; Hayakawa, Kazuo; Sung, Joohon; Harris, Jennifer R; Willemsen, Gonneke; Busjahn, Andreas; Goldberg, Jack H; Rasmussen, Finn; Hur, Yoon-Mi; Boomsma, Dorret I; Sørensen, Thorkild I A; Kaprio, Jaakko; Silventoinen, Karri

    2015-10-01

    A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.

  11. Counseling For Future Shock

    Morgan, Lewis B.

    1974-01-01

    In this article the author looks at some of the searing prophecies made by Alvin Toffler in his book Future Shock and relates them to the world of the professional counselor and the clientele the counselor attempts to serve. (Author)

  12. Life shocks and homelessness.

    Curtis, Marah A; Corman, Hope; Noonan, Kelly; Reichman, Nancy E

    2013-12-01

    We exploited an exogenous health shock-namely, the birth of a child with a severe health condition-to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide.

  13. Unlimited Relativistic Shock Surfing Acceleration

    Ucer, D.; Shapiro, V. D.

    2001-01-01

    Nonrelativistic shock surfing acceleration at quasiperpendicular shocks is usually considered to be a preacceleration mechanism for slow pickup ions to initiate diffusive shock acceleration. In shock surfing, the particle accelerates along the shock front under the action of the convective electric field of the plasma flow. However, the particle also gains kinetic energy normal to the shock and eventually escapes downstream. We consider the case when ions are accelerated to relativistic velocities. In this case, the ions are likely to be trapped for infinitely long times, because the energy of bounce oscillations tends to decrease during acceleration. This suggests the possibility of unlimited acceleration by shock surfing

  14. Technology shocks matter

    Jonas D. M. Fisher

    2002-01-01

    This paper uses the neoclassical growth model to identify the effects of technological change on the US business cycle. In the model there are two sources of technological change: neutral, which effects the production of all goods homogeneously, and investment-specific. Investment-specific shocks are the unique source of the secular trend in the real price of investment goods, while shocks to both kinds of technology are the only factors which affect labor productivity in the long run. Consis...

  15. The Heliospheric Termination Shock

    Jokipii, J. R.

    2013-06-01

    The heliospheric termination shock is a vast, spheroidal shock wave marking the transition from the supersonic solar wind to the slower flow in the heliosheath, in response to the pressure of the interstellar medium. It is one of the most-important boundaries in the outer heliosphere. It affects energetic particles strongly and for this reason is a significant factor in the effects of the Sun on Galactic cosmic rays. This paper summarizes the general properties and overall large-scale structure and motions of the termination shock. Observations over the past several years, both in situ and remote, have dramatically revised our understanding of the shock. The consensus now is that the shock is quite blunt, is with the front, blunt side canted at an angle to the flow direction of the local interstellar plasma relative to the Sun, and is dynamical and turbulent. Much of this new understanding has come from remote observations of energetic charged particles interacting with the shock, radio waves and radiation backscattered from interstellar neutral atoms. The observations and the implications are discussed.

  16. Evaluation of sublingual microcirculation in children with dengue shock

    Daniella Mancino da Luz Caixeta

    2013-07-01

    Full Text Available OBJECTIVE: To report the sublingual microcirculation observed using Sidestream Dark Field imaging in two children with dengue shock. METHOD: Two children, aged 9 and 10 years, were admitted to the pediatric intensive care unit with dengue shock and multiple organ dysfunction. Sublingual microcirculation was assessed in each patient on the first and second days of shock and was assessed a final time when the patients were no longer in shock (on the day prior to extubation using Sidestream Dark Field technology. The De Backer score and microvascular flow index were used for the analyses. RESULTS: Both patients had reduced perfused small vessel density in the first two days and showed predominantly intermittent or no microcirculation flow, as demonstrated by a low microvascular flow index. The blood flow in the large vessels was not affected. Prior to the extubation, the microvascular flow index had increased, although the perfused small vessel density remained diminished, suggesting persistent endothelial dysfunction. CONCLUSIONS: Severe microcirculation changes may be involved in the pathophysiological mechanisms that lead to the final stages of dengue shock, which is frequently irreversible and associated with high mortality rates. Microcirculatory monitoring may help elucidate the physiopathology of dengue shock and prove useful as a prognostic tool or therapeutic target.

  17. Malaysian Education Index (MEI): An Online Indexing and Repository System

    Kabilan, Muhammad Kamarul; Ismail, Hairul Nizam; Yaakub, Rohizani; Yusof, Najeemah Mohd; Idros, Sharifah Noraidah Syed; Umar, Irfan Naufal; Arshad, Muhammad Rafie Mohd.; Idrus, Rosnah; Rahman, Habsah Abdul

    2010-01-01

    This "Project Sheet" describes an on-going project that is being carried out by a group of educational researchers, computer science researchers and librarians from Universiti Sains Malaysia, Penang. The Malaysian Education Index (MEI) has two main functions--(1) Online Indexing System, and (2) Online Repository System. In this brief…

  18. Economic shocks and child welfare: the effect of past economic shocks on child nutritional achievements, schooling and work in rural and urban Ethiopia

    Woldehanna, T.

    2009-01-01

    Using data from the Young Lives younger cohort, we examine the effect of economic shocks on nutritional achievement, schooling and child work of index children (at age 5), controlling for various individual and household characteristics. Shocks that occurred both before and after the child was born

  19. Curved Radio Spectra of Weak Cluster Shocks

    Kang, Hyesung; Ryu, Dongsu

    2015-08-01

    In order to understand certain observed features of arc-like giant radio relics such as the rareness, uniform surface brightness, and curved integrated spectra, we explore a diffusive shock acceleration (DSA) model for radio relics in which a spherical shock impinges on a magnetized cloud containing fossil relativistic electrons. Toward this end, we perform DSA simulations of spherical shocks with the parameters relevant for the Sausage radio relic in cluster CIZA J2242.8+5301, and calculate the ensuing radio synchrotron emission from re-accelerated electrons. Three types of fossil electron populations are considered: a delta-function like population with the shock injection momentum, a power-law distribution, and a power law with an exponential cutoff. The surface brightness profile of the radio-emitting postshock region and the volume-integrated radio spectrum are calculated and compared with observations. We find that the observed width of the Sausage relic can be explained reasonably well by shocks with speed {u}{{s}}˜ 3× {10}3 {km} {{{s}}}-1 and sonic Mach number {M}{{s}}˜ 3. These shocks produce curved radio spectra that steepen gradually over (0.1-10){ν }{br} with a break frequency {ν }{br}˜ 1 GHz if the duration of electron acceleration is ˜60-80 Myr. However, the abrupt increase in the spectral index above ˜1.5 GHz observed in the Sausage relic seems to indicate that additional physical processes, other than radiative losses, operate for electrons with {γ }{{e}}≳ {10}4.

  20. Shocks in fragile matter

    Vitelli, Vincenzo

    2012-02-01

    Non-linear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they unjam, these fragile and disordered solids exhibit vanishing elastic moduli and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are continuously compressed, and demonstrate that the resulting excitations are strongly nonlinear shocks, rather than linear waves. We capture the full dependence of the shock speed on pressure and compression speed by a surprisingly simple analytical model. We also treat shear shocks within a simplified viscoelastic model of nearly-isostatic random networks comprised of harmonic springs. In this case, anharmonicity does not originate locally from nonlinear interactions between particles, as in granular media; instead, it emerges from the global architecture of the network. As a result, the diverging width of the shear shocks bears a nonlinear signature of the diverging isostatic length associated with the loss of rigidity in these floppy networks.

  1. Physics of Collisionless Shocks Space Plasma Shock Waves

    Balogh, André

    2013-01-01

    The present book provides a contemporary systematic treatment of shock waves in high-temperature collisionless plasmas as are encountered in near Earth space and in Astrophysics. It consists of two parts. Part I develops the complete theory of shocks in dilute hot plasmas under the assumption of absence of collisions among the charged particles when the interaction is mediated solely by the self-consistent electromagnetic fields. Such shocks are naturally magnetised implying that the magnetic field plays an important role in their evolution and dynamics. This part treats both subcritical shocks, which dissipate flow energy by generating anomalous resistance or viscosity, and supercritical shocks. The main emphasis is, however, on super-critical shocks where the anomalous dissipation is insufficient to retard the upstream flow. These shocks, depending on the direction of the upstream magnetic field, are distinguished as quasi-perpendicular and quasi-parallel shocks which exhibit different behaviours, reflecti...

  2. Life Shocks and Homelessness

    Corman, Hope; Noonan, Kelly; Reichman, Nancy E.

    2014-01-01

    We exploited an exogenous health shock—namely, the birth of a child with a severe health condition—to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide. PMID:23868747

  3. Health Shocks and Retirement:

    Datta Gupta, Nabanita; Larsen, Mona

    We investigate the effect of an acute health shock on retirement among elderly male workers in Denmark, 1991-1999, and in particular whether various welfare state programs and institutions impinge on the retirement effect. The results show that an acute health event increases the retirement chances...... significant. For the most part, the retirement effect following a health shock seems to be immune to the availability of a multitude of government programs for older workers in Denmark....... benefits in Denmark nor by the promotion of corporate social responsibility initiatives since the mid-1990s. In the late 1990s, however, the retirement rate following a health shock is reduced to 3% with the introduction of the subsidized employment program (fleksjob) but this effect is not strongly...

  4. International Shock-Wave Database: Current Status

    Levashov, Pavel

    2013-06-01

    Shock-wave and related dynamic material response data serve for calibrating, validating, and improving material models over very broad regions of the pressure-temperature-density phase space. Since the middle of the 20th century vast amount of shock-wave experimental information has been obtained. To systemize it a number of compendiums of shock-wave data has been issued by LLNL, LANL (USA), CEA (France), IPCP and VNIIEF (Russia). In mid-90th the drawbacks of the paper handbooks became obvious, so the first version of the online shock-wave database appeared in 1997 (http://www.ficp.ac.ru/rusbank). It includes approximately 20000 experimental points on shock compression, adiabatic expansion, measurements of sound velocity behind the shock front and free-surface-velocity for more than 650 substances. This is still a useful tool for the shock-wave community, but it has a number of serious disadvantages which can't be easily eliminated: (i) very simple data format for points and references; (ii) minimalistic user interface for data addition; (iii) absence of history of changes; (iv) bad feedback from users. The new International Shock-Wave database (ISWdb) is intended to solve these and some other problems. The ISWdb project objectives are: (i) to develop a database on thermodynamic and mechanical properties of materials under conditions of shock-wave and other dynamic loadings, selected related quantities of interest, and the meta-data that describes the provenance of the measurements and material models; and (ii) to make this database available internationally through the Internet, in an interactive form. The development and operation of the ISWdb is guided by an advisory committee. The database will be installed on two mirrored web-servers, one in Russia and the other in USA (currently only one server is available). The database provides access to original experimental data on shock compression, non-shock dynamic loadings, isentropic expansion, measurements of sound

  5. The Shock Routine

    van Hooren, Franca; Kaasch, Alexandra; Starke, Peter

    2014-01-01

    in Australia, Belgium, the Netherlands and Sweden over the course of four global economic shocks, we ask whether the notion of critical junctures is useful in understanding the nature of change triggered by crisis. The main empirical finding is that fundamental change in the aftermath of an exogenous shock...... is the exception rather than the rule. Instead, incremental ‘crisis routines’ based on existing policy instruments are overwhelmingly used to deal with economic hardship. We discuss these findings in the light of the psychological ‘threat-rigidity’ effect and reflect on their consequences for theories...

  6. Walkability Index

    The Walkability Index dataset characterizes every Census 2010 block group in the U.S. based on its relative walkability. Walkability depends upon characteristics of the built environment that influence the likelihood of walking being used as a mode of travel. The Walkability Index is based on the EPA's previous data product, the Smart Location Database (SLD). Block group data from the SLD was the only input into the Walkability Index, and consisted of four variables from the SLD weighted in a formula to create the new Walkability Index. This dataset shares the SLD's block group boundary definitions from Census 2010. The methodology describing the process of creating the Walkability Index can be found in the documents located at ftp://newftp.epa.gov/EPADataCommons/OP/WalkabilityIndex.zip. You can also learn more about the Smart Location Database at https://edg.epa.gov/data/Public/OP/Smart_Location_DB_v02b.zip.

  7. Generation of high pressure shocks relevant to the shock-ignition intensity regime

    Batani, D.; Antonelli, L.; Atzeni, S.; Badziak, J.; Baffigi, F.; Chodukowski, T.; Consoli, F.; Cristoforetti, G.; De Angelis, R.; Dudžák, Roman; Folpini, G.; Giuffrida, L.; Gizzi, L.A.; Kalinowska, Z.; Koester, P.; Krouský, Eduard; Krůs, Miroslav; Labate, L.; Levato, Tadzio; Maheut, Y.; Malka, G.; Margarone, Daniele; Marocchino, A.; Nejdl, Jaroslav; Nicolai, Ph.; O’Dell, T.; Pisarczyk, T.; Renner, Oldřich; Rhee, Y.-J.; Ribeyre, X.; Richetta, M.; Rosinski, M.; Sawicka, Magdalena; Schiavi, A.; Skála, Jiří; Šmíd, Michal; Spindloe, Ch.; Ullschmied, Jiří; Velyhan, Andriy; Vinci, T.

    2014-01-01

    Roč. 21, č. 3 (2014), 032710-032710 ISSN 1070-664X R&D Projects: GA MŠk(CZ) LC528; GA MŠk LM2010014 Institutional support: RVO:61389021 ; RVO:68378271 Keywords : High-pressure shocks * shock ignition * inertial confinement fusion * PALS laser Subject RIV: BL - Plasma and Gas Discharge Physics; BL - Plasma and Gas Discharge Physics (FZU-D) Impact factor: 2.142, year: 2014 http://dx.doi.org/10.1063/1.4869715

  8. Shock absorber in Ignalina NPP

    Bulavas, A.; Muralis, J.

    1996-09-01

    Theoretical calculation and experimental analysis of models of shock absorber in Ignalina NPP is presented. The results obtained from the investigation with model of shock absorber coincide with the theoretical calculation. (author). 2 figs., 3 refs

  9. Shock Response of Boron Carbide

    Dandekar, D. P. (Dattatraya Purushottam)

    2001-01-01

    .... The present work was undertaken to determine tensile/spall strength of boron carbide under plane shock wave loading and to analyze all available shock compression data on boron carbide materials...

  10. Fascinating World of Shock Waves

    Srimath

    travelling at supersonic speeds (more than the sound speed at ... actual earth- quake, travel at supersonic speeds. .... The time scale of the shock wave is also important ..... real lithotripsy where a shock wave is used shatter the kidney stones!

  11. INTERFERENCE OF UNIDIRECTIONAL SHOCK WAVES

    P. V. Bulat

    2015-05-01

    Full Text Available Subject of study.We consider interference of unidirectional shock waves or, as they are called, catching up shock waves. The scope of work is to give a classification of the shock-wave structures that arise in this type of interaction of shock waves, and the area of their existence. Intersection of unidirectional shock waves results in arising of a shock-wave structure at the intersection point, which contains the main shock wave, tangential discontinuity and one more reflected gas-dynamic discontinuity of unknown beforehand type. The problem of determining the type of reflected discontinuity is the main problem that one has to solve in the study of catching shock waves interference. Main results.The paper presents the pictures of shock-wave structures arising at the interaction of catching up shock waves. The areas with a regular and irregular unidirectional interaction of shocks are described. Characteristic shock-wave structures are of greatest interest, where reflected gas-dynamic discontinuity degenerates into discontinuous characteristics. Such structures have a number of extreme properties. We have found the areas of existence for such shock-wave structures. There are also areas in which the steady-state solution is not available. The latter has determined revival of interest for the theoretical study of the problem, because the facts of sudden shock-wave structure destruction inside the air intake of supersonic aircrafts at high Mach numbers have been discovered. Practical significance.The theory of interference for unidirectional shock waves and design procedure are usable in the design of supersonic air intakes. It is also relevant for application possibility investigation of catching up oblique shock waves to create overcompressed detonation in perspective detonation air-jet and rocket engines.

  12. Shock tube Multiphase Experiments

    Middlebrooks, John; Allen, Roy; Paudel, Manoj; Young, Calvin; Musick, Ben; McFarland, Jacob

    2017-11-01

    Shock driven multiphase instabilities (SDMI) are unique physical phenomena that have far-reaching practical applications in engineering and science. The instability is present in high energy explosions, scramjet combustors, and supernovae events. The SDMI arises when a multiphase interface is impulsively accelerated by the passage of a shockwave. It is similar in development to the Richtmyer-Meshkov (RM) instability however, particle-to-gas coupling is the driving mechanism of the SDMI. As particle effects such as lag and phase change become more prominent, the SDMI's development begins to significantly deviate from the RM instability. We have developed an experiment for studying the SDMI in our shock tube facility. In our experiments, a multiphase interface is created using a laminar jet and flowed into the shock tube where it is accelerated by the passage of a planar shockwave. The interface development is captured using CCD cameras synchronized with planar laser illumination. This talk will give an overview of new experiments conducted to examine the development of a shocked cylindrical multiphase interface. The effects of Atwood number, particle size, and a second acceleration (reshock) of the interface will be discussed.

  13. Teleconnected food supply shocks

    Bren d'Amour, Christopher; Wenz, Leonie; Kalkuhl, Matthias; Steckel, Jan Christoph; Creutzig, Felix

    2016-03-01

    The 2008-2010 food crisis might have been a harbinger of fundamental climate-induced food crises with geopolitical implications. Heat-wave-induced yield losses in Russia and resulting export restrictions led to increases in market prices for wheat across the Middle East, likely contributing to the Arab Spring. With ongoing climate change, temperatures and temperature variability will rise, leading to higher uncertainty in yields for major nutritional crops. Here we investigate which countries are most vulnerable to teleconnected supply-shocks, i.e. where diets strongly rely on the import of wheat, maize, or rice, and where a large share of the population is living in poverty. We find that the Middle East is most sensitive to teleconnected supply shocks in wheat, Central America to supply shocks in maize, and Western Africa to supply shocks in rice. Weighing with poverty levels, Sub-Saharan Africa is most affected. Altogether, a simultaneous 10% reduction in exports of wheat, rice, and maize would reduce caloric intake of 55 million people living in poverty by about 5%. Export bans in major producing regions would put up to 200 million people below the poverty line at risk, 90% of which live in Sub-Saharan Africa. Our results suggest that a region-specific combination of national increases in agricultural productivity and diversification of trade partners and diets can effectively decrease future food security risks.

  14. The effect of health shocks on smoking and obesity.

    Sundmacher, Leonie

    2012-08-01

    To investigate whether negative changes in their own health (i.e. health shocks) or in that of a smoking or obese household member, lead smokers to quit smoking and obese individuals to lose weight. The study is informed by economic models ('rational addiction' and 'demand for health' models) which offer hypotheses on the relationship between health shocks and health-related behaviour. Each hypothesis was tested applying a discrete-time hazard model with random effects using up to ten waves of the German Socioeconomic Panel (GSOEP) and statistics on cigarette, food and beverage prices provided by the Federal Statistical Office. Health shocks had a significant positive impact on the probability that smokers quit during the same year in which they experienced the health shock. Health shocks of a smoking household member between year t-2 and t-1 also motivated smoking cessation, although statistical evidence for this was weaker. Health shocks experienced by obese individuals or their household members had, on the other hand, no significant effect on weight loss, as measured by changes in Body Mass Index (BMI). The results of the study suggest that smokers are aware of the risks associated with tobacco consumption, know about effective strategies to quit smoking, and are willing to quit for health-related reasons. In contrast, there was no evidence for changes in health-related behaviour among obese individuals after a health shock.

  15. STEREO interplanetary shocks and foreshocks

    Blanco-Cano, X.; Kajdič, P.; Aguilar-Rodríguez, E.; Russell, C. T.; Jian, L. K.; Luhmann, J. G.

    2013-01-01

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and θ Bn ∼20-86°. We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr ≤0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at ∼1 AU and have been producing suprathermal particles for a shorter time.

  16. STEREO interplanetary shocks and foreshocks

    Blanco-Cano, X. [Instituto de Geofisica, UNAM, CU, Coyoacan 04510 DF (Mexico); Kajdic, P. [IRAP-University of Toulouse, CNRS, Toulouse (France); Aguilar-Rodriguez, E. [Instituto de Geofisica, UNAM, Morelia (Mexico); Russell, C. T. [ESS and IGPP, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095 (United States); Jian, L. K. [NASA Goddard Space Flight Center, Greenbelt, MD and University of Maryland, College Park, MD (United States); Luhmann, J. G. [SSL, University of California Berkeley (United States)

    2013-06-13

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and {theta}{sub Bn}{approx}20-86 Degree-Sign . We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr {<=}0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at {approx}1 AU and have been producing suprathermal particles for a shorter time.

  17. AP Index

    National Oceanic and Atmospheric Administration, Department of Commerce — Planetary Amplitude index - Bartels 1951. The a-index ranges from 0 to 400 and represents a K-value converted to a linear scale in gammas (nanoTeslas)--a scale that...

  18. Hugoniot and refractive indices of bromoform under shock compression

    Liu, Q. C.; Zeng, X. L.; Zhou, X. M.; Luo, S. N.

    2018-01-01

    We investigate physical properties of bromoform (liquid CHBr3) including compressibility and refractive index under dynamic extreme conditions of shock compression. Planar shock experiments are conducted along with high-speed laser interferometry. Our experiments and previous results establish a linear shock velocity-particle velocity relation for particle velocities below 1.77 km/s, as well as the Hugoniot and isentropic compression curves up to ˜21 GPa. Shock-state refractive indices of CHBr3 up to 2.3 GPa or ˜26% compression, as a function of density, can be described with a linear relation and follows the Gladstone-Dale relation. The velocity corrections for laser interferometry measurements at 1550 nm are also obtained.

  19. Conservatism implications of shock test tailoring for multiple design environments

    Baca, Thomas J.; Bell, R. Glenn; Robbins, Susan A.

    1987-01-01

    A method for analyzing shock conservation in test specifications that have been tailored to qualify a structure for multiple design environments is discussed. Shock test conservation is qualified for shock response spectra, shock intensity spectra and ranked peak acceleration data in terms of an Index of Conservation (IOC) and an Overtest Factor (OTF). The multi-environment conservation analysis addresses the issue of both absolute and average conservation. The method is demonstrated in a case where four laboratory tests have been specified to qualify a component which must survive seven different field environments. Final judgment of the tailored test specification is shown to require an understanding of the predominant failure modes of the test item.

  20. Diabetes mellitus and cardiogenic shock in acute myocardial infarction

    Lindholm, M G; Boesgaard, S; Torp-Pedersen, C

    2005-01-01

    AIMS: Cardiogenic shock is the leading cause of in-hospital mortality after acute myocardial infarction (MI). This study investigates the importance of age and preexisting diabetes mellitus on the incidence and prognosis of cardiogenic shock in a large group of consecutive patients with MI. METHODS...... nondiabetics and 10.6% among diabetics. Age, wall motion index, reinfarction, and the absence of thrombolytic treatment were significant independent predictors of mortality in patients with cardiogenic shock. Intriguingly, diabetes was not a significant predictor for short- and long-term mortality...... AND RESULTS: Baseline characteristics and in-hospital complications to the infarction were prospectively recorded in 6676 patients with MI. Ten-year mortality was collected. Diabetes was present in 10.8% of the total population. A total of 443 developed cardiogenic shock with an incidence of 6.2% among...

  1. Hugoniot and refractive indices of bromoform under shock compression

    Q. C. Liu

    2018-01-01

    Full Text Available We investigate physical properties of bromoform (liquid CHBr3 including compressibility and refractive index under dynamic extreme conditions of shock compression. Planar shock experiments are conducted along with high-speed laser interferometry. Our experiments and previous results establish a linear shock velocity−particle velocity relation for particle velocities below 1.77 km/s, as well as the Hugoniot and isentropic compression curves up to ∼21 GPa. Shock-state refractive indices of CHBr3 up to 2.3 GPa or ∼26% compression, as a function of density, can be described with a linear relation and follows the Gladstone-Dale relation. The velocity corrections for laser interferometry measurements at 1550 nm are also obtained.

  2. Shock Dynamics in Stellar Outbursts. I. Shock Formation

    Ro, Stephen; Matzner, Christopher D., E-mail: ro@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada)

    2017-05-20

    Wave-driven outflows and non-disruptive explosions have been implicated in pre-supernova outbursts, supernova impostors, luminous blue variable eruptions, and some narrow-line and superluminous supernovae. To model these events, we investigate the dynamics of stars set in motion by strong acoustic pulses and wave trains, focusing on nonlinear wave propagation, shock formation, and an early phase of the development of a weak shock. We identify the shock formation radius, showing that a heuristic estimate based on crossing characteristics matches an exact expansion around the wave front and verifying both with numerical experiments. Our general analytical condition for shock formation applies to one-dimensional motions within any static environment, including both eruptions and implosions. We also consider the early phase of shock energy dissipation. We find that waves of super-Eddington acoustic luminosity always create shocks, rather than damping by radiative diffusion. Therefore, shock formation is integral to super-Eddington outbursts.

  3. Twin's Birth-Order Differences in Height and Body Mass Index From Birth to Old Age: A Pooled Study of 26 Twin Cohorts Participating in the CODATwins Project

    Yokoyama, Y.; Jelenkovic, A.; Sund, R.; Sung, J.; Hopper, J.L.; Ooki, S.; Heikkilä, K.; Aaltonen, S.; Tarnoki, A.D.; Tarnoki, D.L.; Willemsen, G.; Bartels, M.; van Beijsterveldt, C.E.M.; Saudino, K.J.; Cutler, T.L.; Nelson, T.L.; Whitfield, K.E.; Wardle, J.; Llewellyn, C.H.; Fisher, A.; He, M.; Ding, X.; Bjerregaard-Andersen, M.; Beck-Nielsen, H.; Sodemann, M.; Song, Y.M.; Yang, S.; Lee, K.; Jeong, H.U.; Knafo-Noam, A.; Mankuta, D.; Abramson, L.; Burt, S.A.; Klump, K.L.; Ordonana, J.R.; Sanchez-Romera, J.F.; Colodro-Conde, L.; Harris, J.R.; Brandt, I.; Sevenius Nilsen, T.; Craig, J.M.; Saffery, R.; Ji, F.; Ning, F.; Pang, Z.; Dubois, L.; Boivin, M.; Brendgen, M.; Dionne, G.; Vitaro, F.; Martin, N.G.; Medland, S.E.; Montgomery, G.W.; Magnusson, P.K.E.; Pedersen, N.L.; Dahl Aslan, A.K.; Tynelius, P.; Haworth, C.M.A.; Plomin, R.; Rebato, E.; Rose, R.J.; Goldberg, J.H.; Rasmussen, F.; Hur, Y.M.; Sørensen, T.I.A.; Boomsma, D.I.; Kaprio, J.; Silventoinen, K.

    2016-01-01

    We analyzed birth order differences in means and variances of height and body mass index (BMI) in monozygotic (MZ) and dizygotic (DZ) twins from infancy to old age. The data were derived from the international CODATwins database. The total number of height and BMI measures from 0.5 to 79.5 years of

  4. Grain destruction in interstellar shocks

    Seab, C.G.; Shull, J.M.

    1984-01-01

    One of the principal methods for removing grains from the Interstellar Medium is to destroy them in shock waves. Previous theoretical studies of shock destruction have generally assumed only a single size and type of grain; most do not account for the effect of the grain destruction on the structure of the shock. Earlier calculations have been improved in three ways: first, by using a ''complete'' grain model including a distribution of sizes and types of grains; second, by using a self-consistent shock structure that incorporates the changing elemental depletions as the grains are destroyed; and third, by calculating the shock-processed ultraviolet extinction curves for comparison with observations. (author)

  5. EpiCollect+: linking smartphones to web applications for complex data collection projects [v1; ref status: indexed, http://f1000r.es/3vk

    David M. Aanensen

    2014-08-01

    Full Text Available Previously, we have described the development of the generic mobile phone data gathering tool, EpiCollect, and an associated web application, providing two-way communication between multiple data gatherers and a project database. This software only allows data collection on the phone using a single questionnaire form that is tailored to the needs of the user (including a single GPS point and photo per entry, whereas many applications require a more complex structure, allowing users to link a series of forms in a linear or branching hierarchy, along with the addition of any number of media types accessible from smartphones and/or tablet devices (e.g., GPS, photos, videos, sound clips and barcode scanning. A much enhanced version of EpiCollect has been developed (EpiCollect+. The individual data collection forms in EpiCollect+ provide more design complexity than the single form used in EpiCollect, and the software allows the generation of complex data collection projects through the ability to link many forms together in a linear (or branching hierarchy. Furthermore, EpiCollect+ allows the collection of multiple media types as well as standard text fields, increased data validation and form logic. The entire process of setting up a complex mobile phone data collection project to the specification of a user (project and form definitions can be undertaken at the EpiCollect+ website using a simple ‘drag and drop’ procedure, with visualisation of the data gathered using Google Maps and charts at the project website. EpiCollect+ is suitable for situations where multiple users transmit complex data by mobile phone (or other Android devices to a single project web database and is already being used for a range of field projects, particularly public health projects in sub-Saharan Africa. However, many uses can be envisaged from education, ecology and epidemiology to citizen science.

  6. Bubble Dynamics and Shock Waves

    2013-01-01

    This volume of the Shock Wave Science and Technology Reference Library is concerned with the interplay between bubble dynamics and shock waves. It is divided into four parts containing twelve chapters written by eminent scientists. Topics discussed include shock wave emission by laser generated bubbles (W Lauterborn, A Vogel), pulsating bubbles near boundaries (DM Leppinen, QX Wang, JR Blake), interaction of shock waves with bubble clouds (CD Ohl, SW Ohl), shock propagation in polydispersed bubbly liquids by model equations (K Ando, T Colonius, CE Brennen. T Yano, T Kanagawa,  M Watanabe, S Fujikawa) and by DNS (G Tryggvason, S Dabiri), shocks in cavitating flows (NA Adams, SJ Schmidt, CF Delale, GH Schnerr, S Pasinlioglu) together with applications involving encapsulated bubble dynamics in imaging (AA Doinikov, A Novell, JM Escoffre, A Bouakaz),  shock wave lithotripsy (P Zhong), sterilization of ships’ ballast water (A Abe, H Mimura) and bubbly flow model of volcano eruptions ((VK Kedrinskii, K Takayama...

  7. Climate Shocks and Conflict: Evidence from colonial Nigeria

    Papaioannou, K.I.

    2014-01-01

    This paper offers a historical micro-level analysis of the impact of climatic shocks on the incidence of conflict in colonial Nigeria (1912–1945). Primary historical sources on court cases, prisoners and homicides are used to construct an index of socio-political conflict using principal component

  8. Climate Shocks and Conflict: Evidence from colonial Nigeria

    Papaioannou, Kostadis

    This paper offers a historical micro-level analysis of the impact of climatic shocks on the incidence of conflict in colonial Nigeria (1912–1945). Primary historical sources on court cases, prisoners and homicides are used to construct an index of socio-political conflict using principal component

  9. Cosmic-ray acceleration at stellar wind terminal shocks

    Webb, G.M.; Forman, M.A.; Axford, W.I.

    1985-01-01

    Steady-state, spherically symmetric, analytic solutions of the cosmic-ray transport equations, applicable to the problem of acceleration of cosmic rays at the terminal shock to a stellar wind, are studied. The spectra, gradients, and flow patterns of particle modulated and accelerated by the stellar wind and shock are investigated by means of monoenergetic-source solutions at finite radius, as well as solutions with monoenergetic and power-law Galactic spectra. The solutions obtained apply in the test particle limit in which the cosmic rays do not modify the background flow. The solutions show a characteristic power-law momentum spectrum for accelerated particles and a more complex spectrum of particles that are decelerated in the stellar wind. The power-law spectral index depends on the compression ratio of the shock and on the modulation parameters characterizing propagation conditions in the upstream and downstream regions of the shock. Solutions of the transport equations for the total density N (integrated over all energies), pressure P/sub c/, and energy flux F/sub c/ of Galactic cosmic rays interacting with a stellar wind and shock are also studied. The density N(r) increases with radius r, and for strong shocks with large enough modulation parameters, there may be a significant enhancement of the pressure of weakly relativistic particles near the shock compared to the cosmic-ray background pressure P/sub infinity/. The emergent energy flux at infinity is of the order of 4π R 2 V 1 P/sub infinity/ (V 1 is wind velocity upstream of the shock, R is shock radius)

  10. AA Index

    National Oceanic and Atmospheric Administration, Department of Commerce — The geomagnetic aa index provides a long climatology of global geomagnetic activity using 2 antipodal observatories at Greenwich and Melbourne- IAGA Bulletin 37,...

  11. Walkability Index

    U.S. Environmental Protection Agency — The Walkability Index dataset characterizes every Census 2010 block group in the U.S. based on its relative walkability. Walkability depends upon characteristics of...

  12. Diversity Index

    Town of Chapel Hill, North Carolina — This map service summarizes racial and ethnic diversity in the United States in 2012.The Diversity Index shows the likelihood that two persons chosen at random from...

  13. AUTHOR INDEX

    a granitic terrain of southern India using factor analysis and GIS. 1059. Radhakrishna M see Dev Sheena V .... Landslide susceptibility analysis using Probabilistic. Certainty Factor ... index via entropy-difference analysis. 687. Yidana Sandow ...

  14. Intelligent indexing

    Farkas, J.

    1992-01-01

    In this paper we discuss the relevance of artificial intelligence to the automatic indexing of natural language text. We describe the use of domain-specific semantically-based thesauruses and address the problem of creating adequate knowledge bases for intelligent indexing systems. We also discuss the relevance of the Hilbert space ι 2 to the compact representation of documents and to the definition of the similarity of natural language texts. (author). 17 refs., 2 figs

  15. Intelligent indexing

    Farkas, J

    1993-12-31

    In this paper we discuss the relevance of artificial intelligence to the automatic indexing of natural language text. We describe the use of domain-specific semantically-based thesauruses and address the problem of creating adequate knowledge bases for intelligent indexing systems. We also discuss the relevance of the Hilbert space {iota}{sup 2} to the compact representation of documents and to the definition of the similarity of natural language texts. (author). 17 refs., 2 figs.

  16. Adjustable Shock Absorbers

    Adamiec, Radek

    2012-01-01

    Bakalářská práce obsahuje přehled používaných tlumičů osobních automobilů, závodních automobilů a motocyklů. Jsou zde popsány systémy t lumením, konstrukce tlumičů a vidlic používaných u motocyklů. Dále je zde přehled prvků používaných u podvozků automobilů. This bachelor´s thesis contains the survey of the shock absorbers of passenger cars, racing cars and motorcycles. Are described damping systems, the design used shock absorbers and forks for motorcycles. Then there is the list of the e...

  17. Radiative relativistic shock adiabate

    Tsintsadze, L.N.; Nishikawa, K.

    1997-01-01

    The influences of thermal radiation on the state equation of shock waves, derived in the previous paper [L. N. Tsintsadze, Phys. Plasmas 2, 4462 (1995)], are studied and a series of relations of thermodynamic quantities that hold for shock waves are derived. It is shown that the presence of radiation can strongly change the compressibility of the plasma. It is well known that for polytropic gases the compressibility cannot change more than four times the initial value in the case of nonrelativistic temperatures. The numerical calculations show that there are no such restrictions, when the radiation energy exceeds the kinetic energy of the plasma. The ultrarelativistic temperature range is also covered in our numerical calculations. Also studied are the influences of the radiation on the PT and the TV diagrams. A significant modification due to radiation is found in every case studied. copyright 1997 American Institute of Physics

  18. POSTURAL SHOCK IN PREGNANCY

    Wilkening, Ralph L.; Knauer, John; Larson, Roger K.

    1955-01-01

    Signs and symptoms of shock may be produced in some patients in late pregnancy by putting them in the dorsal recumbent posture. Change from this position will relieve the condition. The features of the supine hypotensive syndrome can be duplicated by applying pressure to the abdomen with the patient in a lateral position. The postural variations of venous pressure, blood pressure, and pulse appear to be due to obstruction of venous return from the lower portion of the body caused by the large uterus of late pregnancy compressing the vena cava. When shock is observed in a woman in late pregnancy, she should be turned to a lateral position before more active measures of treatment are begun. ImagesFigure 1. PMID:14351983

  19. Bow shock data analysis

    Zipf, Edward C.; Erdman, Peeter W.

    1994-08-01

    The University of Pittsburgh Space Physics Group in collaboration with the Army Research Office (ARO) modeling team has completed a systematic organization of the shock and plume spectral data and the electron temperature and density measurements obtained during the BowShock I and II rocket flights which have been submitted to the AEDC Data Center, has verified the presence of CO Cameron band emission during the Antares engine burn and for an extended period of time in the post-burn plume, and have adapted 3-D radiation entrapment codes developed by the University of Pittsburgh to study aurora and other atmospheric phenomena that involve significant spatial effects to investigate the vacuum ultraviolet (VUV) and extreme ultraviolet (EUV) envelope surrounding the re-entry that create an extensive plasma cloud by photoionization.

  20. Shock Isolation Elements Testing for High Input Loadings. Volume III. Mechanical Shock Isolation Elements.

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*SPRINGS, (*SHOCK(MECHANICS), REDUCTION), TORSION BARS, ELASTOMERS, DAMPING, EQUATIONS OF MOTION, MODEL TESTS, TEST METHODS, NUCLEAR EXPLOSIONS, HARDENING.

  1. Shock resistance testing

    Pouard, M.

    1984-03-01

    In the framework of mechanical tests and to answer the different requests for tests, the T.C.R (Transport Conditionnement et Retraitement) laboratory got test facilities. These installations allow to carry out tests of resistance to shocks, mainly at the safety level of components of nuclear power plants, mockups of transport casks for fuel elements and transport containers for radioactive materials. They include a tower and a catapult. This paper give a decription of the facilities and explain their operation way [fr

  2. On Modeling Risk Shocks

    Dorofeenko, Victor; Lee, Gabriel; Salyer, Kevin; Strobel, Johannes

    2016-01-01

    Within the context of a financial accelerator model, we model time-varying uncertainty (i.e. risk shocks) through the use of a mixture Normal model with time variation in the weights applied to the underlying distributions characterizing entrepreneur productivity. Specifically, we model capital producers (i.e. the entrepreneurs) as either low-risk (relatively small second moment for productivity) and high-risk (relatively large second moment for productivity) and the fraction of both types is...

  3. The Shock Doctrine

    Dionysios K. Solomos; Dimitrios N. Koumparoulis

    2011-01-01

    Naomi Klein attempts to redefine the economic history discovering the historical continuities and to reveal the neoliberal theory which functions via the utilization of specific “tools”. The state of shock is the key for the opponents of Chicago School and Milton Friedman in order for them to establish neoliberal policies and to promote the deregulated capitalism which includes less welfare state, less public sector, less regulation, weakened labor unions, privatizations and laissez-faire. Th...

  4. Extracorporeal shock wave therapy (ESWT) in urology

    Fojecki, Grzegorz Lukasz; Thiessen, Stefan; Osther, Palle Jörn Sloth

    2017-01-01

    PURPOSE: The objective was to evaluate high-level evidence studies of extracorporeal shock wave therapy (ESWT) for urological disorders. METHODS: We included randomized controlled trials reporting outcomes of ESWT in urology. Literature search on trials published in English using EMBASE, Medline...... deviation and plaque size were observed. Four studies on erectile dysfunction (ED) including 337 participants were included. Using International Index of Erectile Function (IIEF-EF) and erectile hardness scale (EHS) data suggested a significant positive effect of ESWT in phosphodiesterase-5 inhibitor (PDE-5...

  5. Characterization of shocked beryllium

    Papin P.A.

    2012-08-01

    Full Text Available While numerous studies have investigated the low-strain-rate constitutive response of beryllium, the combined influence of high strain rate and temperature on the mechanical behavior and microstructure of beryllium has received limited attention over the last 40 years. In the current work, high strain rate tests were conducted using both explosive drive and a gas gun to accelerate the material. Prior studies have focused on tensile loading behavior, or limited conditions of dynamic strain rate and/or temperature. Two constitutive strength (plasticity models, the Preston-Tonks-Wallace (PTW and Mechanical Threshold Stress (MTS models, were calibrated using common quasi-static and Hopkinson bar data. However, simulations with the two models give noticeably different results when compared with the measured experimental wave profiles. The experimental results indicate that, even if fractured by the initial shock loading, the Be remains sufficiently intact to support a shear stress following partial release and subsequent shock re-loading. Additional “arrested” drive shots were designed and tested to minimize the reflected tensile pulse in the sample. These tests were done to both validate the model and to put large shock induced compressive loads into the beryllium sample.

  6. Selfsimilar time dependent shock structures

    Beck, R.; Drury, L.O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The same argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions

  7. Selfsimilar time dependent shock structures

    Beck, R.; Drury, L. O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The ame argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions.

  8. Virginia ESI: INDEX (Index Polygons)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all hardcopy cartographic products produced as part of the Environmental Sensitivity Index...

  9. Generation of Two Successive Shock Waves Focusedto a Common Focal Point

    Šunka, Pavel; Stelmashuk, Vitaliy; Babický, Václav; Člupek, Martin; Beneš, J.; Poučková, P.; Kašpar, J.; Bodnár, M.

    2006-01-01

    Roč. 34, č. 4 (2006), s. 1382-1385 ISSN 0093-3813. [International Power Modulator Conference. Washington D.C., 14.5.2006-18.5.2006] R&D Projects: GA ČR(CZ) GA202/05/0685 Institutional research plan: CEZ:AV0Z20430508 Keywords : Cavitation collpse * double shocks * focused shock waves * liver injury * secondary shocks Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.144, year: 2006

  10. Shock Heating of the Merging Galaxy Cluster A521

    Bourdin, H.; Mazzotta, P.; Markevitch, M.; Giacintucci, S.; Brunetti, G.

    2013-01-01

    A521 is an interacting galaxy cluster located at z = 0.247, hosting a low-frequency radio halo connected to an eastern radio relic. Previous Chandra observations hinted at the presence of an X-ray brightness edge at the position of the relic, which may be a shock front. We analyze a deep observation of A521 recently performed with XMM-Newton in order to probe the cluster structure up to the outermost regions covered by the radio emission. The cluster atmosphere exhibits various brightness and temperature anisotropies. In particular, two cluster cores appear to be separated by two cold fronts. We find two shock fronts, one that was suggested by Chandra and that is propagating to the east, and another to the southwestern cluster outskirt. The two main interacting clusters appear to be separated by a shock-heated region, which exhibits a spatial correlation with the radio halo. The outer edge of the radio relic coincides spatially with a shock front, suggesting that this shock is responsible for the generation of cosmic-ray electrons in the relic. The propagation direction and Mach number of the shock front derived from the gas density jump, M = 2.4 +/- 0.2, are consistent with expectations from the radio spectral index, under the assumption of Fermi I acceleration mechanism.

  11. Indexing mechanisms

    Wood, A.G.; Parker, G.E.; Berry, R.

    1976-01-01

    It is stated that the indexing mechanism described can be used in a nuclear reactor fuel element inspection rig. It comprises a tubular body adapted to house a canister containing a number of fuel elements located longtitudinally, and has two chucks spaced apart for displacing the fuel elements longitudinally in a stepwise manner, together with a plunger mechanism for displacing them successively into the chucks. A measuring unit is located between the chucks for measuring the diameter of the fuel elements at intervals about their circumferences, and a secondary indexing mechanism is provided for rotating the measuring unit in a stepwise manner. (U.K.)

  12. Risk shocks and housing markets

    Dorofeenko, Viktor; Lee, Gabriel S.; Salyer, Kevin D.

    2010-01-01

    Abstract: This paper analyzes the role of uncertainty in a multi-sector housing model with financial frictions. We include time varying uncertainty (i.e. risk shocks) in the technology shocks that affect housing production. The analysis demonstratesthat risk shocks to the housing production sector are a quantitatively important impulse mechanism for the business cycle. Also, we demonstrate that bankruptcy costs act as an endogenous markup factor in housing prices; as a consequence, the volati...

  13. Health shocks and risk aversion.

    Decker, Simon; Schmitz, Hendrik

    2016-12-01

    We empirically assess whether a health shock influences individual risk aversion. We use grip strength data to obtain an objective health shock indicator. In order to account for the non-random nature of our data regression-adjusted matching is employed. Risk preferences are traditionally assumed to be constant. However, we find that a health shock increases individual risk aversion. The finding is robust to a series of sensitivity analyses and persists for at least four years after the shock. Income changes do not seem to be the driving mechanism. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Shock in the emergency department

    Holler, Jon Gitz; Henriksen, Daniel Pilsgaard; Mikkelsen, Søren

    2016-01-01

    BACKGROUND: The knowledge of the frequency and associated mortality of shock in the emergency department (ED) is limited. The aim of this study was to describe the incidence, all-cause mortality and factors associated with death among patients suffering shock in the ED. METHODS: Population...... failures. Outcomes were annual incidence per 100,000 person-years at risk (pyar), all-cause mortality at 0-7, and 8-90 days and risk factors associated with death. RESULTS: We identified 1646 of 438,191 (0.4 %) ED patients with shock at arrival. Incidence of shock increased from 53.8 to 80.6 cases per 100...

  15. Shock compression of diamond crystal

    Kondo, Ken-ichi; Ahrens, Thomas J.

    1983-01-01

    Two shock wave experiments employing inclined mirrors have been carried out to determine the Hugoniot elastic limit (HEL), final shock state at 191 and 217 GPa, and the post-shock state of diamond crystal, which is shock-compressed along the intermediate direction between the and crystallographic axes. The HEL wave has a velocity of 19.9 ± 0.3 mm/µsec and an amplitude of 63 ± 28 GPa. An alternate interpretation of the inclined wedge mirror streak record suggests a ramp precursor wave and th...

  16. Economic impact of oil price shocks on the Turkish economy in the coming decades: A dynamic CGE analysis

    Aydin, Levent; Acar, Mustafa

    2011-01-01

    As a small open economy, Turkey depends on both imported oil and natural gas, importing almost two-thirds of its primary energy demand. This paper analyzes the economic effects of oil price shocks for Turkey as a small, open oil- and gas-importing country. To analyze the potential long-term effects of oil price shocks on macroeconomic variables of interest, including GDP, consumer price inflation, indirect tax revenues, trade balance, and carbon emissions, we developed TurGEM-D, a dynamic multisectoral general equilibrium model for the Turkish economy. Using TurGEM-D, we analyzed the impact of oil price shocks under three distinct scenarios: reference, high and low oil prices. The simulation results show that these oil prices have very significant effects on macro indicators and carbon emissions in the Turkish economy. - Research highlights: → World oil prices are projected to rise in coming decade, to around $185 per barrel in 2020. → If this occurs in Turkey, how to quantitatively evaluate the impacts on Turkish economy? → Cumulative output loss resulting from world oil prices increased by 121% can be as large as 14%. → Cumulative inflation as measured by CPI index can be nearly 5% under a fixed exchange rate regime. → Cumulative carbon emissions fall by around 51.7% without using any tools for climate change policy.

  17. Author Index

    user1

    Astr. (2012) 33, 419–420. Author Index. 419. AGGARWAL SUNNY. Photoionization Cross-Section of Chlorine-like Iron, 291. AMBASTHA ASHOK see Das, A. C., 1. ARAKIDA HIDEYOSHI. Effect of Inhomogeneity of the Universe on a Gravitationally. Bound Local System: A No-Go Result for Explaining the Secular Increase in.

  18. AUTHOR INDEX

    automorphic solutions to fractional order abstract integro-differential equations. 323. Afrouzi G A see Ala Samira ... 521. Agarwal Praveen. Certain fractional integral operators and the generalized multi-index Mittag- ... of positive solutions for sys- tems of second order multi-point bound- ary value problems on time scales 353.

  19. Predictive Values of the New Sarcopenia Index by the Foundation for the National Institutes of Health Sarcopenia Project for Mortality among Older Korean Adults

    Kim, Jung Hee; Moon, Jae Hoon; Choi, Sung Hee; Lim, Soo; Lim, Jae-Young; Kim, Ki Woong; Park, Kyong Soo; Jang, Hak Chul

    2016-01-01

    Objective We evaluated the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project’s recommended criteria for sarcopenia’s association with mortality among older Korean adults. Methods We conducted a community-based prospective cohort study which included 560 (285 men and 275 women) older Korean adults aged ≥65 years. Muscle mass (appendicular skeletal muscle mass-to-body mass index ratio (ASM/BMI)), handgrip strength, and walking velocity were evaluated in association with all-cause mortality during 6-year follow-up. Both the lowest quintile for each parameter (ethnic-specific cutoff) and FNIH-recommended values were used as cutoffs. Results Forty men (14.0%) and 21 women (7.6%) died during 6-year follow-up. The deceased subjects were older and had lower ASM, handgrip strength, and walking velocity. Sarcopenia defined by both low lean mass and weakness had a 4.13 (95% CI, 1.69–10.11) times higher risk of death, and sarcopenia defined by a combination of low lean mass, weakness, and slowness had a 9.56 (3.16–28.90) times higher risk of death after adjusting for covariates in men. However, these significant associations were not observed in women. In terms of cutoffs of each parameter, using the lowest quintile showed better predictive values in mortality than using the FNIH-recommended values. Moreover, new muscle mass index, ASM/BMI, provided better prognostic values than ASM/height2 in all associations. Conclusions New sarcopenia definition by FNIH was better able to predict 6-year mortality among Korean men. Moreover, ethnic-specific cutoffs, the lowest quintile for each parameter, predicted the higher risk of mortality than the FNIH-recommended values. PMID:27832145

  20. Added sugars and sugar-sweetened beverage consumption, dietary carbohydrate index and depression risk in the Seguimiento Universidad de Navarra (SUN) Project.

    Sanchez-Villegas, Almudena; Zazpe, Itziar; Santiago, Susana; Perez-Cornago, Aurora; Martinez-Gonzalez, Miguel A; Lahortiga-Ramos, Francisca

    2018-01-01

    The association between added sugars or sugar-sweetened beverage consumption and the risk of depression, as well as the role of carbohydrate quality in depression risk, remains unclear. Among 15 546 Spanish university graduates from the Seguimiento Universidad de Navarra (SUN) prospective cohort study, diet was assessed with a validated 136-item semi-quantitative FFQ at baseline and at 10-year follow-up. Cumulative average consumption of added sugars, sweetened drinks and an overall carbohydrate quality index (CQI) were calculated. A better CQI was associated with higher whole-grain consumption and fibre intake and lower glycaemic index and consumption of solid (instead of liquid) carbohydrates. Clinical diagnoses of depression during follow-up were classified as incident cases. Multivariable time-dependent Cox regression models were used to estimate hazard ratios (HR) of depression according to consumption of added sugars, sweetened drinks and CQI. We observed 769 incident cases of depression. Participants in the highest quartile of added sugars consumption showed a significant increment in the risk of depression (HR=1·35; 95 % CI 1·09, 1·67, P=0·034), whereas those in the highest quartile of CQI (upper quartile of the CQI) showed a relative risk reduction of 30 % compared with those in the lowest quartile of the CQI (HR=0·70; 95 % CI 0·56, 0·88). No significant association between sugar-sweetened beverage consumption and depression risk was found. Higher added sugars and lower quality of carbohydrate consumption were associated with depression risk in the SUN Cohort. Further studies are necessary to confirm the reported results.

  1. A Shocking Solar Nebula?

    Liffman, Kurt

    2009-01-01

    It has been suggested that shock waves in the solar nebula formed the high temperature materials observed in meteorites and comets. It is shown that the temperatures at the inner rim of the solar nebula could have been high enough over a sufficient length of time to produce chondrules, CAIs, refractory dust grains and other high-temperature materials observed in comets and meteorites. The solar bipolar jet flow may have produced an enrichment of 16O in the solar nebula over time and the chond...

  2. Myths of "shock therapy".

    Fink, M

    1977-09-01

    The author discusses the myths of the ECT process--that shock and the convulsion are essential, memory loss and brain damage are inescapable, and little is known of the process--and assesses the fallacies in these ideas. Present views of the ECT process suggest that its mode of action in depression may best be described as a prolonged form of diencephalic stimulation, particularly useful to affect the hypothalamic dysfunctions that characterize depressive illness. The author emphasizes the need for further study of this treatment modality and for self-regulation by the profession.

  3. AUTHOR INDEX

    pean High Power Laser Energy Research. Facility project. 759. Patidar R K ... pilot study. 1287. Pradhan Asima see Gharekhan Anita. 1281. Pradhan M K see Mukherjee A. 99 .... Testing fundamental symmetries using radioactive ion beams at ...

  4. Gravitational shock waves and extreme magnetomaterial shock waves

    Lichnerowicz, Andre.

    1975-01-01

    Within an astrophysical context corresponding to high densities, a self-gravitating model is studied, which is the set of an extreme material medium of infinite conductivity and of a magnetic field. Corresponding shock waves generate necessarily, in general, gravitational shock waves [fr

  5. Shock Producers and Shock Absorbers in the Crisis

    Sinn, Hans-Werner

    2009-01-01

    It is not surprising that the U.S. has been by far the world’s largest shock producer in this crisis. The big shock absorbers on the other hand were Japan, Russia and Germany, whose exports shrank more than their imports.

  6. Simulations of Converging Shock Collisions for Shock Ignition

    Sauppe, Joshua; Dodd, Evan; Loomis, Eric

    2016-10-01

    Shock ignition (SI) has been proposed as an alternative to achieving high gain in inertial confinement fusion (ICF) targets. A central hot spot below the ignition threshold is created by an initial compression pulse, and a second laser pulse drives a strong converging shock into the fuel. The collision between the rebounding shock from the compression pulse and the converging shock results in amplification of the converging shock and increases the hot spot pressure above the ignition threshold. We investigate shock collision in SI drive schemes for cylindrical targets with a polystyrene foam interior using radiation-hydrodynamics simulations with the RAGE code. The configuration is similar to previous targets fielded on the Omega laser. The CH interior results in a lower convergence ratio and the cylindrical geometry facilitates visualization of the shock transit using an axial X-ray backlighter, both of which are important for comparison to potential experimental measurements. One-dimensional simulations are used to determine shock timing, and the effects of low mode asymmetries in 2D computations are also quantified. LA-UR-16-24773.

  7. Bifurcation parameters of a reflected shock wave in cylindrical channels of different roughnesses

    Penyazkov, O.; Skilandz, A.

    2018-03-01

    To investigate the effect of bifurcation on the induction time in cylindrical shock tubes used for chemical kinetic experiments, one should know the parameters of the bifurcation structure of a reflected shock wave. The dynamics and parameters of the shock wave bifurcation, which are caused by reflected shock wave-boundary layer interactions, are studied experimentally in argon, in air, and in a hydrogen-nitrogen mixture for Mach numbers M = 1.3-3.5 in a 76-mm-diameter shock tube without any ramp. Measurements were taken at a constant gas density behind the reflected shock wave. Over a wide range of experimental conditions, we studied the axial projection of the oblique shock wave and the pressure distribution in the vicinity of the triple Mach configuration at 50, 150, and 250 mm from the endwall, using side-wall schlieren and pressure measurements. Experiments on a polished shock tube and a shock tube with a surface roughness of 20 {μ }m Ra were carried out. The surface roughness was used for initiating small-scale turbulence in the boundary layer behind the incident shock wave. The effect of small-scale turbulence on the homogenization of the transition zone from the laminar to turbulent boundary layer along the shock tube perimeter was assessed, assuming its influence on a subsequent stabilization of the bifurcation structure size versus incident shock wave Mach number, as well as local flow parameters behind the reflected shock wave. The influence of surface roughness on the bifurcation development and pressure fluctuations near the wall, as well as on the Mach number, at which the bifurcation first develops, was analyzed. It was found that even small additional surface roughness can lead to an overshoot in pressure growth by a factor of two, but it can stabilize the bifurcation structure along the shock tube perimeter.

  8. Structural VAR analysis of monetary transmission mechanism and central bank’s response to equity volatility shock in Taiwan

    Lo, Chi-Sheng

    2016-01-01

    This research applies recursive Structural Vector Auto Regression (SVAR) model with short-run restriction into two kinds of shocks: monetary and volatility. The first SVAR estimates the shock of contractionary monetary policy on Taiwan’s key monthly macroeconomic variables including exports, CPI, exchange rate, money supply, and Taiwan Weighted Stock Exchange (TWSE) Index. The second SVAR estimates the shock of Generalized Autoregressive Conditional Heteroskedasticity (GARCH) volatility of TW...

  9. Afghanistan Index

    Linnet, Poul Martin

    2007-01-01

    basis. The data are divided into different indicators such as security, polls, drug, social, economic, refugees etc. This represents a practical division and does not indicate that a picture as to for instance security can be obtained by solely looking at the data under security. In order to obtain...... a more valid picture on security this must incorporate an integrated look on all data meaning that for instance the economic data provides an element as to the whole picture of security.......The Afghanistan index is a compilation of quantitative and qualitative data on the reconstruction and security effort in Afghanistan. The index aims at providing data for benchmarking of the international performance and thus provides the reader with a quick possibility to retrieve valid...

  10. 30th International Symposium on Shock Waves

    Sadot, Oren; Igra, Ozer

    2017-01-01

    These proceedings collect the papers presented at the 30th International Symposium on Shock Waves (ISSW30), which was held in Tel-Aviv Israel from July 19 to July 24, 2015. The Symposium was organized by Ortra Ltd. The ISSW30 focused on the state of knowledge of the following areas: Nozzle Flow, Supersonic and Hypersonic Flows with Shocks, Supersonic Jets, Chemical Kinetics, Chemical Reacting Flows, Detonation, Combustion, Ignition, Shock Wave Reflection and Interaction, Shock Wave Interaction with Obstacles, Shock Wave Interaction with Porous Media, Shock Wave Interaction with Granular Media, Shock Wave Interaction with Dusty Media, Plasma, Magnetohyrdrodynamics, Re-entry to Earth Atmosphere, Shock Waves in Rarefied Gases, Shock Waves in Condensed Matter (Solids and Liquids), Shock Waves in Dense Gases, Shock Wave Focusing, Richtmyer-Meshkov Instability, Shock Boundary Layer Interaction, Multiphase Flow, Blast Waves, Facilities, Flow Visualization, and Numerical Methods. The two volumes serve as a reference ...

  11. Indicator for success of obesity reduction programs in adolescents: Body composition or body mass index? evaluating a school-based health promotion project after 12 weeks of intervention

    Naser Kalantari

    2017-01-01

    Full Text Available Background: Obesity in adolescence is the strongest risk factor for obesity in adulthood. This study aimed to evaluate the effects of a comprehensive lifestyle intervention on different anthropometric indices in 12–16-year-old boy adolescents after 12 Weeks of Intervention. Methods: A total of 96 male adolescents from two schools participated in this study. The schools were randomly assigned to intervention (53 students and control school (43 students. Height and weight of students were measured and their body mass index (BMI was calculated. Body fat percent (BF and body muscle percent (BM was assessed using a bioimpedance analyzer considering the age, gender, and height of students at baseline and after intervention. The obesity reduction intervention was implemented in the intervention school based on the Ottawa charter for health promotion. Results: Twelve weeks of intervention decreased BF percent in the intervention group in comparison with the control group (decreased by 1.81% in the intervention group and increased by 0.39% in the control group, P < 0.01. However, weight, BMI, and BM did not change significantly. Conclusions: The result of this study showed that a comprehensive lifestyle intervention decreased the body fat percent in obese adolescents, although these changes was not reflected in the BMI. It is possible that BMI is not a good indicator in assessment of the success of obesity management intervention.

  12. Twin's Birth-Order Differences in Height and Body Mass Index From Birth to Old Age: A Pooled Study of 26 Twin Cohorts Participating in the CODATwins Project.

    Yokoyama, Yoshie; Jelenkovic, Aline; Sund, Reijo; Sung, Joohon; Hopper, John L; Ooki, Syuichi; Heikkilä, Kauko; Aaltonen, Sari; Tarnoki, Adam D; Tarnoki, David L; Willemsen, Gonneke; Bartels, Meike; van Beijsterveldt, Toos C E M; Saudino, Kimberly J; Cutler, Tessa L; Nelson, Tracy L; Whitfield, Keith E; Wardle, Jane; Llewellyn, Clare H; Fisher, Abigail; He, Mingguang; Ding, Xiaohu; Bjerregaard-Andersen, Morten; Beck-Nielsen, Henning; Sodemann, Morten; Song, Yun-Mi; Yang, Sarah; Lee, Kayoung; Jeong, Hoe-Uk; Knafo-Noam, Ariel; Mankuta, David; Abramson, Lior; Burt, S Alexandra; Klump, Kelly L; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Harris, Jennifer R; Brandt, Ingunn; Nilsen, Thomas Sevenius; Craig, Jeffrey M; Saffery, Richard; Ji, Fuling; Ning, Feng; Pang, Zengchang; Dubois, Lise; Boivin, Michel; Brendgen, Mara; Dionne, Ginette; Vitaro, Frank; Martin, Nicholas G; Medland, Sarah E; Montgomery, Grant W; Magnusson, Patrik K E; Pedersen, Nancy L; Aslan, Anna K Dahl; Tynelius, Per; Haworth, Claire M A; Plomin, Robert; Rebato, Esther; Rose, Richard J; Goldberg, Jack H; Rasmussen, Finn; Hur, Yoon-Mi; Sørensen, Thorkild I A; Boomsma, Dorret I; Kaprio, Jaakko; Silventoinen, Karri

    2016-04-01

    We analyzed birth order differences in means and variances of height and body mass index (BMI) in monozygotic (MZ) and dizygotic (DZ) twins from infancy to old age. The data were derived from the international CODATwins database. The total number of height and BMI measures from 0.5 to 79.5 years of age was 397,466. As expected, first-born twins had greater birth weight than second-born twins. With respect to height, first-born twins were slightly taller than second-born twins in childhood. After adjusting the results for birth weight, the birth order differences decreased and were no longer statistically significant. First-born twins had greater BMI than the second-born twins over childhood and adolescence. After adjusting the results for birth weight, birth order was still associated with BMI until 12 years of age. No interaction effect between birth order and zygosity was found. Only limited evidence was found that birth order influenced variances of height or BMI. The results were similar among boys and girls and also in MZ and DZ twins. Overall, the differences in height and BMI between first- and second-born twins were modest even in early childhood, while adjustment for birth weight reduced the birth order differences but did not remove them for BMI.

  13. Molecular diagnostics of interstellar shocks

    Hartquist, T.W.; Oppenheimer, M.; Dalgarno, A.

    1980-01-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km s -1 Substantial enhancements are predicted in the concentrations of the molecules H 2 S, SO, and SiO compared to those anticipated in cold interstellar clouds

  14. Molecular diagnostics of interstellar shocks

    Hartquist, T. W.; Dalgarno, A.; Oppenheimer, M.

    1980-02-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km/sec. Substantial enhancements are predicted in the concentrations of the molecules H2S, SO, and SiO compared to those anticipated in cold interstellar clouds.

  15. How Culture Shock Affects Communication.

    Barna, LaRay M.

    The paper defines the term "culture shock" and discusses the changes that this state can make in a person's behavior. Culture shock refers to the emotional and physiological reaction of high activation that is brought about by sudden immersion in a new culture. Because one's own culture shields one from the unknown and reduces the need to make…

  16. Molecular diagnostics of interstellar shocks

    Hartquist, T. W.; Dalgarno, A.; Oppenheimer, M.

    1980-01-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km/sec. Substantial enhancements are predicted in the concentrations of the molecules H2S, SO, and SiO compared to those anticipated in cold interstellar clouds.

  17. Shock wave treatment in medicine

    Home; Journals; Journal of Biosciences; Volume 30; Issue 2 ... In the present paper we discuss the basic theory and application of shock waves and its history in medicine. The idea behind using shock wave therapy for orthopedic diseases is the stimulation of healing in tendons, surrounding tissue and bones. This is a ...

  18. Shock wave treatment in medicine

    Unknown

    to open surgery, the cost of the ESWT is very reasonable. But nevertheless it is necessary to improve the basic un ... In second group, shock waves are used to measure distances because of the low energy loss over large distances ... pared to a piezoelectric hydrophone. The rise time of an electrohydraulic generated shock ...

  19. Numerical modeling of slow shocks

    Winske, D.

    1987-01-01

    This paper reviews previous attempt and the present status of efforts to understand the structure of slow shocks by means of time dependent numerical calculations. Studies carried out using MHD or hybrid-kinetic codes have demonstrated qualitative agreement with theory. A number of unresolved issues related to hybrid simulations of the internal shock structure are discussed in some detail. 43 refs., 8 figs

  20. Dynamic shock wave: hammer blow

    Lackme, Claude

    1978-01-01

    The general properties of shocks, their generation and the conditions of reflexion to an interface are dealt with in turn. By then applying these concepts to a liquid column and its environment (wall, free area, closing devices) the hammer blow is presented as being a relatively weak shock [fr

  1. Slow shocks and their transition to fast shocks in the inner solar wind

    Wang, Y.C.

    1987-01-01

    The jump conditions of MHD shocks may be directly calculated as functions of three upstream conditions: the shock Alfven number based on the normal component of the relative shock speed, the shock angle, and the plasma β value. The shock Alfven number is less than 1 for a slow shock and greater than 1 for a fast shock. A traveling, forward shock can be a slow shock in coronal space, where the Alfven speed is of the order of 1000 km/s. The surface of a forward slow shock has a bow-shaped geometry with its nose facing toward the sun. The decrease in the Alfven speed at increasing heliocentric distance causes the shock Alfven number of a forward slow shock to become greater than 1, and the shock eventually evolves from a slow shock into a fast shock. During the transition the shock system consists of a slow shock, a fast shock, and a rotational discontinuity. They intersect along a closed transition line. As the system moves outward from the sun, the area enclosed by the transition line expands, the fast shock grows stronger, and the slow shock becomes weaker. Eventually, the slow shock diminishes, and the entire shock system evolves into a forward fast shock. copyrightAmerican Geophysical Union 1987

  2. Electron acceleration in a wavy shock front

    Vandas, Marek; Karlický, Marian

    2011-01-01

    Roč. 531, July (2011), A55/1-A55/8 ISSN 0004-6361 R&D Projects: GA AV ČR(CZ) IAA300030701; GA MŠk(CZ) ME09009; GA ČR GA205/09/0170; GA ČR GAP209/10/1680 Grant - others:EU(XE) EC FP7 SWIFF 263340 Institutional research plan: CEZ:AV0Z10030501 Keywords : shock waves * acceleration of particles * magnetic fields * solar radio radiation Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.587, year: 2011

  3. Shocking matter to extreme conditions

    Gupta, Y.M.; Sharma, S.M.

    1997-01-01

    A good understanding of the thermodynamic response of matter at high compression and high energy densities is important to several areas of physics. Shock-wave experiments are uniquely suited for obtaining data at extreme conditions, and a shock-compressed matter can be viewed as a condensed system with or without dissociation or as a strongly coupled plasma. This article reviews work by Da Silva et al. in which irradiances ranging from 5x10 superscript 12 to 2x10 superscript 14 W/cm 2 were used to generate 8- to 10-ns square pulses in liquid deuterium. The authors demonstrated negligible pre-heating of the sample, steady propagation of the shock wave, and direct determination of the shock wave velocity along with particle velocity and density in the shocked state. Da Silva et al. results are compared with models and other experimental information, and the usefulness of the data in other areas is assessed. 11 refs., 1 fig

  4. Electron transport and shock ignition

    Bell, A R; Tzoufras, M, E-mail: t.bell1@physics.ox.ac.uk [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)

    2011-04-15

    Inertial fusion energy (IFE) offers one possible route to commercial energy generation. In the proposed 'shock ignition' route to fusion, the target is compressed at a relatively low temperature and then ignited using high intensity laser irradiation which drives a strong converging shock into the centre of the fuel. With a series of idealized calculations we analyse the electron transport of energy into the target, which produces the pressure responsible for driving the shock. We show that transport in shock ignition lies near the boundary between ablative and heat front regimes. Moreover, simulations indicate that non-local effects are significant in the heat front regime and might lead to increased efficiency by driving the shock more effectively and reducing heat losses to the plasma corona.

  5. Oscillating nonlinear acoustic shock waves

    Gaididei, Yuri; Rasmussen, Anders Rønne; Christiansen, Peter Leth

    2016-01-01

    We investigate oscillating shock waves in a tube using a higher order weakly nonlinear acoustic model. The model includes thermoviscous effects and is non isentropic. The oscillating shock waves are generated at one end of the tube by a sinusoidal driver. Numerical simulations show that at resona......We investigate oscillating shock waves in a tube using a higher order weakly nonlinear acoustic model. The model includes thermoviscous effects and is non isentropic. The oscillating shock waves are generated at one end of the tube by a sinusoidal driver. Numerical simulations show...... polynomial in the space and time variables, we find analytical approximations to the observed single shock waves in an infinitely long tube. Using perturbation theory for the driven acoustic system approximative analytical solutions for the off resonant case are determined....

  6. The association between change in body mass index and upper aerodigestive tract cancers in the ARCAGE project: multicenter case-control study.

    Park, Sungshim Lani

    2011-03-15

    Previous studies reported an inverse relationship between body mass index (BMI) and upper aerodigestive tract (UADT) cancers. Examining change in BMI over time may clarify these previous observations. We used data from 2,048 cases and 2,173 hospital- and population-based controls from ten European countries (alcohol-related cancers and genetic susceptibility in Europe study) to investigate the relationship with BMI and adult change in BMI on UADT cancer risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for associations between BMI at three time intervals and BMI change on UADT cancer development, adjusting for center, age, sex, education, fruit and vegetable intake, smoking and alcohol consumption. We found an inverse relationship between UADT cancers and BMI at time of interview and 2 years before interview. No association was found with BMI at 30 years of age. Regarding BMI change between age 30 and 2 years before interview, BMI decrease (BMI change <-5%) vs. BMI stability (-5% ≤ BMI change <5%) showed no overall association with UADT cancers (OR = 1.15; 95% CI = 0.89, 1.49). An increase in BMI (BMI change ≥+5%) was inversely associated with UADT cancers (OR = 0.74; 95% CI = 0.62, 0.89). BMI gain remained inversely associated across all subsites except for esophageal cancer. When stratified by smoking or by drinking, association with BMI gain was detected only in drinkers and smokers. In conclusion, BMI gain is inversely associated with UADT cancers. These findings may be influenced by smoking and\\/or drinking behaviors and\\/or the development of preclinical UADT cancers and should be corroborated in studies of a prospective nature.

  7. Childhood body mass index at 5.5 years mediates the effect of prenatal maternal stress on daughters' age at menarche: Project Ice Storm.

    Duchesne, A; Liu, A; Jones, S L; Laplante, D P; King, S

    2017-04-01

    Early pubertal timing is known to put women at greater risk for adverse physiological and psychological health outcomes. Of the factors that influence girls' pubertal timing, stress experienced during childhood has been found to advance age at menarche (AAM). However, it is not known if stress experienced by mothers during or in the months before conception can be similarly associated with earlier pubertal timing. Prenatal maternal stress (PNMS) is associated with metabolic changes, such as increased childhood adiposity and risk of obesity, that have been associated with earlier menarchal age. Using a prospective longitudinal design, the present study tested whether PNMS induced by a natural disaster is either directly associated with earlier AAM, or whether there is an indirect association mediated through increased girls' body mass index (BMI) during childhood. A total of 31 girls, whose mothers were exposed to the Quebec's January 1998 ice storm during pregnancy were followed from 6 months to 5 1/2 to 5.5 years of age. Mother's stress was measured within 6 months of the storm. BMI was measured at 5.5 years, and AAM was assessed through teen's self-report at 13.5 and 15.5 years of age. Results revealed that greater BMI at 5.5 years mediated the effect of PNMS on decreasing AAM [B=-0.059, 95% confidence intervals (-0.18, -0.0035)]. The present study is the first to demonstrate that maternal experience of stressful conditions during pregnancy reduces AAM in the offspring through its effects on childhood BMI. Future research should consider the impact of AAM on other measures of reproductive ability.

  8. Investigation of the Propagation Characteristics of Underwater Shock Waves in Underwater Drilling Blasting

    Xin Liu

    2018-01-01

    Full Text Available During the first-stage project of the main channel of Ningbo-Zhoushan Port’s Shipu Harbor, underwater shock waves were monitored. By analyzing a typical measured pressure time history curve, the characteristics of underwater shock waves in an engineering context were obtained. We obtained a traditional exponential attenuation formula for underwater shock waves based on the measured data, simplified the model of underwater drilling blasting based on engineering practice, deduced a revised formula for underwater shock wave peak overpressure on the basis of dimensional analysis, established a linear fitting model, and obtained the undetermined coefficients of the revised formula using a linear regression analysis. In addition, the accuracies of the two formulas used to predict underwater shock wave peak overpressure and the significance order of influence and influence mechanism of factors included in the revised formula on the underwater shock wave peak overpressure were discussed.

  9. Credit markets and the propagation of monetary policy shocks

    Boháček, Radim; Mendizábal, H. R.

    2007-01-01

    Roč. 39, č. 6 (2007), s. 1429-1455 ISSN 0022-2879 R&D Projects: GA AV ČR IAA700850602 Institutional research plan: CEZ:AV0Z70850503 Keywords : credit * monetary policy shock * heterogeneous agents Subject RIV: AH - Economics Impact factor: 0.947, year: 2007

  10. Thermal shock behaviour of mullite-cordierite refractory materials

    Boccaccini, D. N.; Leonelli, C.; Romagnoli, M.; Pellacani, G. C.; Veronesi, P.; Dlouhý, Ivo; Boccaccini, A. R.

    2007-01-01

    Roč. 106, č. 3 (2007), s. 142-148 ISSN 1743-6753 R&D Projects: GA AV ČR IAA200410502 Institutional research plan: CEZ:AV0Z20410507 Keywords : refraktory materials * thermal shock * fracutre toughness Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 1.074, year: 2007

  11. Effect of lateral radiative losses on radiative shock propagation

    Busquet, M.; Audit, E.; González, M.; Stehlé, C.; Thais, F.; Acef, O.; Bauduin, D.; Barroso, P.; Rus, Bedřich; Kozlová, Michaela; Polan, Jiří; Mocek, Tomáš

    2007-01-01

    Roč. 3, - (2007), s. 8-11 ISSN 1574-1818 EU Projects: European Commission(XE) 506350 - LASERLAB-EUROPE Institutional research plan: CEZ:AV0Z10100523 Keywords : radiative shocks * laboratory astrophysics Subject RIV: BH - Optics, Masers, Lasers

  12. Shocks in the relativistic transonic accretion with low angular momentum

    Suková, Petra; Charzynski, S.; Janiuk, A.

    2017-01-01

    Roč. 472, č. 4 (2017), s. 4327-4342 ISSN 0035-8711 R&D Projects: GA ČR(CZ) GJ17-06962Y Institutional support: RVO:67985815 Keywords : accretion discs * hydrodynamics * shock waves Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 4.961, year: 2016

  13. Automated interplanetary shock detection and its application to Wind observations

    Krupařová, Oksana; Maksimovic, M.; Šafránková, J.; Němeček, Z.; Santolík, Ondřej; Krupař, Vratislav

    2013-01-01

    Roč. 118, č. 8 (2013), 4793–4803 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GAP209/12/2394 Institutional support: RVO:68378289 Keywords : Interplanetary shocks * instruments and techniques Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.440, year: 2013 http://onlinelibrary.wiley.com/doi/10.1002/jgra.50468/abstract

  14. Projection Methods

    Wagner, Falko Jens; Poulsen, Mikael Zebbelin

    1999-01-01

    When trying to solve a DAE problem of high index with more traditional methods, it often causes instability in some of the variables, and finally leads to breakdown of convergence and integration of the solution. This is nicely shown in [ESF98, p. 152 ff.].This chapter will introduce projection...... methods as a way of handling these special problems. It is assumed that we have methods for solving normal ODE systems and index-1 systems....

  15. Shock waves & explosions

    Sachdev, PL

    2004-01-01

    Understanding the causes and effects of explosions is important to experts in a broad range of disciplines, including the military, industrial and environmental research, aeronautic engineering, and applied mathematics. Offering an introductory review of historic research, Shock Waves and Explosions brings analytic and computational methods to a wide audience in a clear and thorough way. Beginning with an overview of the research on combustion and gas dynamics in the 1970s and 1980s, the author brings you up to date by covering modeling techniques and asymptotic and perturbative methods and ending with a chapter on computational methods.Most of the book deals with the mathematical analysis of explosions, but computational results are also included wherever they are available. Historical perspectives are provided on the advent of nonlinear science, as well as on the mathematical study of the blast wave phenomenon, both when visualized as a point explosion and when simulated as the expansion of a high-pressure ...

  16. Analysis of shock implosion

    Mishkin, E.A.; Alejaldre, C. (Polytechnic Inst. of New York, Brooklyn (USA))

    1984-06-01

    An imploding shock wave, coming from infinity, moves through an ideal gas with the adiabatic constant ..gamma... To define a single-valued self-similar coefficient over the whole classical interval 1<..gamma..

  17. The cosmic-ray shock structure problem for relativistic shocks

    Webb, G. M.

    1985-01-01

    The time asymptotic behaviour of a relativistic (parallel) shock wave significantly modified by the diffusive acceleration of cosmic-rays is investigated by means of relativistic hydrodynamical equations for both the cosmic-rays and thermal gas. The form of the shock structure equation and the dispersion relation for both long and short wavelength waves in the system are obtained. The dependence of the shock acceleration efficiency on the upstream fluid spped, long wavelength Mach number and the ratio N = P sub co/cP sub co+P sub go)(Psub co and P sub go are the upstream cosmic-ray and thermal gas pressures respectively) are studied.

  18. Cosmic-ray shock acceleration in oblique MHD shocks

    Webb, G. M.; Drury, L. OC.; Volk, H. J.

    1986-01-01

    A one-dimensional, steady-state hydrodynamical model of cosmic-ray acceleration at oblique MHD shocks is presented. Upstream of the shock the incoming thermal plasma is subject to the adverse pressure gradient of the accelerated particles, the J x B force, as well as the thermal gas pressure gradient. The efficiency of the acceleration of cosmic-rays at the shock as a function of the upstream magnetic field obliquity and upstream plasma beta is investigated. Astrophysical applications of the results are briefly discussed.

  19. Utilizing risk index for overdose or serious opioid-induced respiratory depression (RIOSORD) scores to prioritize offer of rescue naloxone in an outpatient veteran population: A telephone-based project.

    Yates, Derek; Frey, Theresa; Montgomery, Jean Charles

    2018-03-26

    Since 2014, the Department of Veterans Affairs (VA) has been working to address the ongoing opioid epidemic through opioid-education initiatives, the development of risk calculators, and other risk stratification tools. One primary focus of VA efforts has been the distribution of rescue naloxone kits to veterans at greatest risk of opioid-related adverse events. The purpose of this project was to identify primary care veterans at highest risk for serious opioid-related adverse events using the Risk Index for Overdose and Serious Opioid-Induced Respiratory Depression (RIOSORD) and offer rescue naloxone kits by telephone-based outreach. RIOSORD is a risk-stratification tool developed and validated within the veteran population. Veterans identified at highest risk of overdose or opioid-related adverse effects were contacted by telephone or letter to offer to provide a rescue naloxone kit between November 1 st , 2016 and February 1 st , 2017. The primary outcome of the project was the percentage of patients contacted that agreed to a naloxone prescription. Secondary outcomes included comparative efficacy of phone versus letter contact and reasons for refusal of naloxone if the offer was declined. Of 41 veterans targeted by this project, most were successfully reached by telephone within three attempts (92.7%, n = 38). Approximately two-thirds of those reached by telephone agreed to a prescription for rescue naloxone (n = 26, 63.4%). The veterans that requested rescue naloxone selected the nasal formulation (n = 17) over the intramuscular auto-injector (n = 9). This project demonstrated that telephone-based outreach can be one method of distributing rescue naloxone to a high-risk patient population without requiring an in-person visit to a provider.

  20. Chondrule destruction in nebular shocks

    Jacquet, Emmanuel; Thompson, Christopher, E-mail: ejacquet@mnhn.fr [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St George Street, Toronto, ON M5S 3H8 (Canada)

    2014-12-10

    Chondrules are millimeter-sized silicate spherules ubiquitous in primitive meteorites, but whose origin remains mysterious. One of the main proposed mechanisms for producing them is melting of solids in shock waves in the gaseous protoplanetary disk. However, evidence is mounting that chondrule-forming regions were enriched in solids well above solar abundances. Given the high velocities involved in shock models, destructive collisions would be expected between differently sized grains after passage of the shock front as a result of differential drag. We investigate the probability and outcome of collisions of particles behind a one-dimensional shock using analytic methods as well as a full integration of the coupled mass, momentum, energy, and radiation equations. Destruction of protochondrules seems unavoidable for solid/gas ratios ε ≳ 0.1, and possibly even for solar abundances because of 'sandblasting' by finer dust. A flow with ε ≳ 10 requires much smaller shock velocities (∼2 versus 8 km s{sup –1}) in order to achieve chondrule-melting temperatures, and radiation trapping allows slow cooling of the shocked fragments. Initial destruction would still be extensive; although re-assembly of millimeter-sized particles would naturally occur by grain sticking afterward, the compositional heterogeneity of chondrules may be difficult to reproduce. We finally note that solids passing through small-scale bow shocks around few kilometer-sized planetesimals might experience partial melting and yet escape fragmentation.

  1. Shocks inside CMEs: A survey of properties from 1997 to 2006

    Lugaz, N.; Farrugia, C. J.; Smith, C. W.; Paulson, K.

    2015-04-01

    We report on 49 fast-mode forward shocks propagating inside coronal mass ejections (CMEs) as measured by Wind and ACE at 1 AU from 1997 to 2006. Compared to typical CME-driven shocks, these shocks propagate in different upstream conditions, where the median upstream Alfvén speed is 85 km s-1, the proton β = 0.08 and the magnetic field strength is 8 nT. These shocks are fast with a median speed of 590 km s-1 but weak with a median Alfvénic Mach number of 1.9. They typically compress the magnetic field and density by a factor of 2-3. The most extreme upstream conditions found were a fast magnetosonic speed of 230 km s-1, a plasma β of 0.02, upstream solar wind speed of 740 km s-1 and density of 0.5 cm-3. Nineteen of these complex events were associated with an intense geomagnetic storm (peak Dst under -100 nT) within 12 h of the shock detection at Wind, and 15 were associated with a drop of the storm time Dst index of more than 50 nT between 3 and 9 h after shock detection. We also compare them to a sample of 45 shocks propagating in more typical upstream conditions. We show the average property of these shocks through a superposed epoch analysis, and we present some analytical considerations regarding the compression ratios of shocks in low β regimes. As most of these shocks are measured in the back half of a CME, we conclude that about half the shocks may not remain fast-mode shocks as they propagate through an entire CME due to the large upstream and magnetosonic speeds.

  2. Simulation of mechanical shock environments

    Lalanne, Christian.

    1975-07-01

    Shocks can produce a severe mechanical environment which must be taken into account when designing and developing new equipments. After some mathematical (Laplace and Fourier transforms) and mechanical recalls (response of a one degree freedom system to a sinusoidal excitation), different analysis methods are compared, these methods being the most used now to compare relative severities of tests and establish specifications. A few chapter deal with the different properties of simple, easy to produce, shock shapes. Then some now-in-use programmators or shock-machines specifications are shown. A final chapter concerns acceleration transducers [fr

  3. Particle acceleration in modified shocks

    Drury, L.O'C.; Axford, W.I.; Summers, D.

    1982-01-01

    Efficient particle acceleration in shocks must modify the shock structure with consequent changes in the particle acceleration. This effect is studied and analytic solutions are found describing the diffusive acceleration of particles with momentum independent diffusion coefficients in hyperbolic tangent type velocity transitions. If the input particle spectrum is a delta function, the shock smoothing replaces the truncated power-law downstream particle spectrum by a more complicated form, but one which has a power-law tail at high momenta. For a cold plasma this solution can be made completely self-consistent. Some problems associated with momentum dependent diffusion coefficients are discussed. (author)

  4. INTERFERENCE OF COUNTERPROPAGATING SHOCK WAVES

    P. V. Bulat

    2015-03-01

    Full Text Available The subject of study. We examined the interaction of counterpropagating shock waves. The necessity of counterpropagating shock waves studying occurs at designing of high Mach number modern internal compression air intakes, Ramjets with subsonic and supersonic combustion, in asymmetrical supersonic nozzles and in some other cases. In a sense, this problem is a generalization of the case of an oblique shock reflection from the wall or from the plane of symmetry. With the renewed vigor, the interest to this problem emerged at the end of the 90s. This was due to the start of the programs for flight study at hypersonic speeds. The first experiments performed with air intakes, which realized the interaction of counterpropagating shock waves have shown that the change in flow velocity is accompanied by abrupt alteration of shock-wave structure, the occurrence of nonstationary and oscillatory phenomena. With an increase of flow velocity these phenomena undesirable for aircraft structure became more marked. The reason is that there are two fundamentally different modes of interaction of counterpropagating shock waves: a four-wave regular and a five-wave irregular. The transition from one mode to another can be nonstationary abrupt or gradual, it can also be accompanied by hysteresis. Main results. Criteria for the transition from regular reflection of counterpropagating shock waves to irregular are described: the criterion of von Neumann and the stationary Mach configuration criterion. We described areas in which the transition from one reflection type to another is possible only in abrupt way, as well as areas of possible gradual transition. Intensity dependences of the reflected shock waves from the intensity of interacting counterpropagating shocks were given. Qualitative pictures of shock-wave structures arising from the interaction of counterpropagating shock waves were shown. Calculation results of the intensity of outgoing gas

  5. Particle acceleration in modified shocks

    Drury, L.O' C. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.)); Axford, W.I. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau (Germany, F.R.)); Summers, D. (Memorial Univ. of Newfoundland, St. John' s (Canada))

    1982-03-01

    Efficient particle acceleration in shocks must modify the shock structure with consequent changes in the particle acceleration. This effect is studied and analytic solutions are found describing the diffusive acceleration of particles with momentum independent diffusion coefficients in hyperbolic tangent type velocity transitions. If the input particle spectrum is a delta function, the shock smoothing replaces the truncated power-law downstream particle spectrum by a more complicated form, but one which has a power-law tail at high momenta. For a cold plasma this solution can be made completely self-consistent. Some problems associated with momentum dependent diffusion coefficients are discussed.

  6. Shocks in the Early Universe.

    Pen, Ue-Li; Turok, Neil

    2016-09-23

    We point out a surprising consequence of the usually assumed initial conditions for cosmological perturbations. Namely, a spectrum of Gaussian, linear, adiabatic, scalar, growing mode perturbations not only creates acoustic oscillations of the kind observed on very large scales today, it also leads to the production of shocks in the radiation fluid of the very early Universe. Shocks cause departures from local thermal equilibrium as well as create vorticity and gravitational waves. For a scale-invariant spectrum and standard model physics, shocks form for temperatures 1  GeVUniverse as early as 10^{-30}  sec after the big bang.

  7. Quasilinear simulations of interplanetary shocks and Earth's bow shock

    Afanasiev, Alexandr; Battarbee, Markus; Ganse, Urs; Vainio, Rami; Palmroth, Minna; Pfau-Kempf, Yann; Hoilijoki, Sanni; von Alfthan, Sebastian

    2016-04-01

    We have developed a new self-consistent Monte Carlo simulation model for particle acceleration in shocks. The model includes a prescribed large-scale magnetic field and plasma density, temperature and velocity profiles and a self-consistently computed incompressible ULF foreshock under the quasilinear approximation. Unlike previous analytical treatments, our model is time dependent and takes full account of the anisotropic particle distributions and scattering in the wave-particle interaction process. We apply the model to the problem of particle acceleration at traveling interplanetary (IP) shocks and Earth's bow shock and compare the results with hybrid-Vlasov simulations and spacecraft observations. A qualitative agreement in terms of spectral shape of the magnetic fluctuations and the polarization of the unstable mode is found between the models and the observations. We will quantify the differences of the models and explore the region of validity of the quasilinear approach in terms of shock parameters. We will also compare the modeled IP shocks and the bow shock, identifying the similarities and differences in the spectrum of accelerated particles and waves in these scenarios. The work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324 (HESPERIA). The Academy of Finland is thanked for financial support. We acknowledge the computational resources provided by CSC - IT Centre for Science Ltd., Espoo.

  8. Diaphragmless shock wave generators for industrial applications of shock waves

    Hariharan, M. S.; Janardhanraj, S.; Saravanan, S.; Jagadeesh, G.

    2011-06-01

    The prime focus of this study is to design a 50 mm internal diameter diaphragmless shock tube that can be used in an industrial facility for repeated loading of shock waves. The instantaneous rise in pressure and temperature of a medium can be used in a variety of industrial applications. We designed, fabricated and tested three different shock wave generators of which one system employs a highly elastic rubber membrane and the other systems use a fast acting pneumatic valve instead of conventional metal diaphragms. The valve opening speed is obtained with the help of a high speed camera. For shock generation systems with a pneumatic cylinder, it ranges from 0.325 to 1.15 m/s while it is around 8.3 m/s for the rubber membrane. Experiments are conducted using the three diaphragmless systems and the results obtained are analyzed carefully to obtain a relation between the opening speed of the valve and the amount of gas that is actually utilized in the generation of the shock wave for each system. The rubber membrane is not suitable for industrial applications because it needs to be replaced regularly and cannot withstand high driver pressures. The maximum shock Mach number obtained using the new diaphragmless system that uses the pneumatic valve is 2.125 ± 0.2%. This system shows much promise for automation in an industrial environment.

  9. Shock wave dynamics derivatives and related topics

    Emanuel, George

    2012-01-01

    "...this monograph develops an esoteric niche within shock wave theory. …treats shock waves from an analytical approach assuming perfect gas. Emanuel has made significant contributions to the theory of shock waves and has selected a number of topics that reflect those contributions."-Shock Waves, 2013.

  10. Nonlinearity, Conservation Law and Shocks

    Almost all natural phenomena, and social and economic changes, .... reference moving with velocity c also by the same symbol x and ... abstract as can be seen from the publication of the book Shock Waves and Reaction Diffusion Equation.

  11. Shock Thermodynamic Applied Research Facility

    Federal Laboratory Consortium — The Shock Thermodynamic Applied Research Facility (STAR) facility, within Sandia’s Solid Dynamic Physics Department, is one of a few institutions in the world with a...

  12. Target design for shock ignition

    Schurtz, G; Ribeyre, X; Lafon, M

    2010-01-01

    The conventional approach of laser driven inertial fusion involves the implosion of cryogenic shells of deuterium-tritium ice. At sufficiently high implosion velocities, the fuel ignites by itself from a central hot spot. In order to reduce the risks of hydrodynamic instabilities inherent to large implosion velocities, it was proposed to compress the fuel at low velocity, and ignite the compressed fuel by means of a convergent shock wave driven by an intense spike at the end of the laser pulse. This scheme, known as shock ignition, reduces the risks of shell break-up during the acceleration phase, but it may be impeded by a low coupling efficiency of the laser pulse with plasma at high intensities. This work provides a relationship between the implosion velocity and the laser intensity required to ignite the target by a shock. The operating domain of shock ignition at different energies is described.

  13. Undercuts by Laser Shock Forming

    Wielage, Hanna; Vollertsen, Frank

    2011-01-01

    In laser shock forming TEA-CO 2 -laser induced shock waves are used to form metal foils, such as aluminum or copper. The process utilizes an initiated plasma shock wave on the target surface, which leads to a forming of the foil. A challenge in forming technologies is the manufacturing of undercuts. By conventional forming methods these special forms are not feasible. In this article, it is presented that undercuts in the micro range can be produced by laser shock deep drawing. Different drawing die diameters, drawing die depths and the material aluminum in the thicknesses 20 and 50 μm were investigated. It will be presented that smaller die diameters facilitate undercuts compared to bigger die diameters. The phenomena can be explained by Barlow's formula. Furthermore, it is shown which maximum undercut depth at different die diameters can be reached. To this end, cross-sections of the different parameter combinations are displayed.

  14. Electric Shock Injuries in Children

    ... Issues Listen Español Text Size Email Print Share Electric Shock Injuries in Children Page Content ​When the ... comes into direct contact with a source of electricity, the current passes through it, producing what's called ...

  15. Shock wave interaction with turbulence: Pseudospectral simulations

    Buckingham, A.C.

    1986-01-01

    Shock waves amplify pre-existing turbulence. Shock tube and shock wave boundary layer interaction experiments provide qualitative confirmation. However, shock pressure, temperature, and rapid transit complicate direct measurement. Computational simulations supplement the experimental data base and help isolate the mechanisms responsible. Simulations and experiments, particularly under reflected shock wave conditions, significantly influence material mixing. In these pseudospectral Navier-Stokes simulations the shock wave is treated as either a moving (tracked or fitted) domain boundary. The simulations assist development of code mix models. Shock Mach number and pre-existing turbulence intensity initially emerge as key parameters. 20 refs., 8 figs

  16. The Efficacy of Cognitive Shock

    2015-05-21

    way, causing dissonance or cognitive conflict, so that the mental model has to be ‘accommodated’ to the new data. Categories and knowledge have to...The Efficacy of Cognitive Shock A Monograph by MAJ Anthony L. Marston United States Army School of Advanced Military Studies...DATES COVERED (From - To) JUN 2014 – MAY 2015 4. TITLE AND SUBTITLE The Efficacy of Cognitive Shock 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  17. Pressurized Thermal Shock, Pts

    Boyd, C.

    2008-01-01

    Pressurized Thermal Shock (Pts) refers to a condition that challenges the integrity of the reactor pressure vessel. The root cause of this problem is the radiation embrittlement of the reactor vessel. This embrittlement leads to an increase in the reference temperature for nil ductility transition (RTNDT). RTNDT can increase to the point where the reactor vessel material can loose fracture toughness during overcooling events. The analysis of the risk of having a Pts for a specific plant is a multi-disciplinary problem involving probabilistic risk analysis (PRA), thermal-hydraulic analysis, and ultimately a structural and fracture analysis of the vessel wall. The PRA effort involves the postulation of overcooling events and ultimately leads to an integrated risk analysis. The thermal-hydraulic effort involves the difficult task of predicting the system behavior during a postulated overcooling scenario with a special emphasis on predicting the thermal and mechanic loadings on the reactor pressure vessel wall. The structural and fracture analysis of the reactor vessel wall relies on the thermal-hydraulic conditions as boundary conditions. The US experience has indicated that medium and large diameter primary system breaks dominate the risk of Pts along with scenarios that involve a stuck open valve (and associated system cooldown) that recloses resulting in system re-pressurization while the vessel wall is cool.

  18. Sepsis and septic shock

    Hotchkiss, Richard S.; Moldawer, Lyle L.; Opal, Steven M.; Reinhart, Konrad; Turnbull, Isaiah R.; Vincent, Jean-Louis

    2017-01-01

    For more than two decades, sepsis was defined as a microbial infection that produces fever (or hypothermia), tachycardia, tachypnoea and blood leukocyte changes. Sepsis is now increasingly being considered a dysregulated systemic inflammatory and immune response to microbial invasion that produces organ injury for which mortality rates are declining to 15–25%. Septic shock remains defined as sepsis with hyperlactataemia and concurrent hypotension requiring vasopressor therapy, with in-hospital mortality rates approaching 30–50%. With earlier recognition and more compliance to best practices, sepsis has become less of an immediate life-threatening disorder and more of a long-term chronic critical illness, often associated with prolonged inflammation, immune suppression, organ injury and lean tissue wasting. Furthermore, patients who survive sepsis have continuing risk of mortality after discharge, as well as long-term cognitive and functional deficits. Earlier recognition and improved implementation of best practices have reduced in-hospital mortality, but results from the use of immunomodulatory agents to date have been disappointing. Similarly, no biomarker can definitely diagnose sepsis or predict its clinical outcome. Because of its complexity, improvements in sepsis outcomes are likely to continue to be slow and incremental. PMID:28117397

  19. Effects of Monetary Shocks on Exchange Rate: Empirical Evidence from India

    Sharma Chandan

    2017-08-01

    Full Text Available This paper examines the effect of monetary policy shocks on exchange rate in a Multiple Indicator Approach (MIA framework. This study has employed a monetary policy index of key monetary policy instruments in India (Bank rate, Cash Reserve Ratio, Repo and Reverse Repo rates. The study finds the empirical evidence for puzzling behavior of price level and exchange rate. Both price and exchange rate increase initially in response to a contractionary policy shock. Policy shocks affect output, inflation and exchange rate to an appreciable extent over a forecasting horizon of one year.

  20. Nonlinear Weibel Instability and Turbulence in Strong Collisionless Shocks

    Medvedev, Mikhail M.

    2008-01-01

    This research project was devoted to studies of collisionless shocks, their properties, microphysics and plasma physics of underlying phenomena, such as Weibel instability and generation of small-scale fields at shocks, particle acceleration and transport in the generated random fields, radiation mechanisms from these fields in application to astrophysical phenomena and laboratory experiments (e.g., laser-plasma and beam-plasma interactions, the fast ignition and inertial confinement, etc.). Thus, this study is highly relevant to astrophysical sciences, the inertial confinement program and, in particular, the Fast Ignition concept, etc. It makes valuable contributions to the shock physics, nonlinear plasma theory, as well as to the basic plasma science, in general

  1. Focusing of Shear Shock Waves

    Giammarinaro, Bruno; Espíndola, David; Coulouvrat, François; Pinton, Gianmarco

    2018-01-01

    Focusing is a ubiquitous way to transform waves. Recently, a new type of shock wave has been observed experimentally with high-frame-rate ultrasound: shear shock waves in soft solids. These strongly nonlinear waves are characterized by a high Mach number, because the shear wave velocity is much slower, by 3 orders of magnitude, than the longitudinal wave velocity. Furthermore, these waves have a unique cubic nonlinearity which generates only odd harmonics. Unlike longitudinal waves for which only compressional shocks are possible, shear waves exhibit cubic nonlinearities which can generate positive and negative shocks. Here we present the experimental observation of shear shock wave focusing, generated by the vertical motion of a solid cylinder section embedded in a soft gelatin-graphite phantom to induce linearly vertically polarized motion. Raw ultrasound data from high-frame-rate (7692 images per second) acquisitions in combination with algorithms that are tuned to detect small displacements (approximately 1 μ m ) are used to generate quantitative movies of gel motion. The features of shear shock wave focusing are analyzed by comparing experimental observations with numerical simulations of a retarded-time elastodynamic equation with cubic nonlinearities and empirical attenuation laws for soft solids.

  2. Shock compression of synthetic opal

    Inoue, A; Okuno, M; Okudera, H; Mashimo, T; Omurzak, E; Katayama, S; Koyano, M

    2010-01-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO 4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO 2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  3. Shock compression of synthetic opal

    Inoue, A.; Okuno, M.; Okudera, H.; Mashimo, T.; Omurzak, E.; Katayama, S.; Koyano, M.

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  4. Shock compression of synthetic opal

    Inoue, A; Okuno, M; Okudera, H [Department of Earth Sciences, Kanazawa University Kanazawa, Ishikawa, 920-1192 (Japan); Mashimo, T; Omurzak, E [Shock Wave and Condensed Matter Research Center, Kumamoto University, Kumamoto, 860-8555 (Japan); Katayama, S; Koyano, M, E-mail: okuno@kenroku.kanazawa-u.ac.j [JAIST, Nomi, Ishikawa, 923-1297 (Japan)

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO{sub 4} tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO{sub 2} glass. However, internal silanole groups still remain even at 38.1 GPa.

  5. Electromagnetically driven radiative shocks and their measurements

    Kondo, K.; Watanabe, M.; Nakajima, M.; Kawamura, T.; Horioka, K.

    2005-01-01

    Experimental results on a generation of strong shocks in a compact pulse power device are reported. The characteristics of strong shocks are different from hydrodynamical shocks' because they depend on not only collisions but radiation processes. Radiative shocks are relevant to high energy density phenomena such as the explosions of supernovae. When initial pressure is lower than about 50 mtorr, an interesting structure is confirmed at the shock front, which might indicate a phenomenon proceeded by the radiative process. (author)

  6. Diagnostics of gas behind shock waves by refractive optical techniques

    Blaha, J.

    In a brief outline of optical methods for measuring neutral gas and plasma parameters, techniques are specifically dealt with based on the interferometric measurement of the refractive index. The investigation is shown of gas density changes in a shock tube using the optical Mach-Zehnder interferometer. While in a neutral gas the refractive index is determined by gas density, in a plasma the effects of all components, ie., electrons, ions and atoms are additive. The contributions to refraction from the various components may, in view of the different character and frequencies of the components, be resolved by measurement on more than one wavelength. (J.U.)

  7. Scientific Journal Indexing

    Getulio Teixeira Batista

    2007-08-01

    Full Text Available It is quite impressive the visibility of online publishing compared to offline. Lawrence (2001 computed the percentage increase across 1,494 venues containing at least five offline and five online articles. Results shown an average of 336% more citations to online articles compared to offline articles published in the same venue. If articles published in the same venue are of similar quality, then they concluded that online articles are more highly cited because of their easier access. Thomson Scientific, traditionally concerned with printed journals, announced on November 28, 2005, the launch of Web Citation Index™, the multidisciplinary citation index of scholarly content from institutional and subject-based repositories (http://scientific.thomson. com/press/2005/8298416/. The Web Citation Index from the abstracting and indexing (A&I connects together pre-print articles, institutional repositories and open access (OA journals (Chillingworth, 2005. Basically all research funds are government granted funds, tax payer’s supported and therefore, results should be made freely available to the community. Free online availability facilitates access to research findings, maximizes interaction among research groups, and optimizes efforts and research funds efficiency. Therefore, Ambi-Água is committed to provide free access to its articles. An important aspect of Ambi-Água is the publication and management system of this journal. It uses the Electronic System for Journal Publishing (SEER - http://www.ibict.br/secao.php?cat=SEER. This system was translated and customized by the Brazilian Institute for Science and Technology Information (IBICT based on the software developed by the Public Knowledge Project (Open Journal Systems of the British Columbia University (http://pkp.sfu.ca/ojs/. The big advantage of using this system is that it is compatible with the OAI-PMH protocol for metadata harvesting what greatly promotes published articles

  8. Pressurized thermal shock (PTS)

    Rosso, Ricardo D.; Ventura, Mirta A.

    2006-01-01

    In the present work, a description of Thermal Shock in Pressurized conditions (PTS), and its influence in the treatment of the integrity of the pressure vessel (RPV) of a Pressurized Water Reactor (PWR) and/or of a Heavy water Pressurized water Reactor (PHWR) is made. Generally, the analysis of PTS involves a process of three stages: a-) Modeling with a System Code of relevant thermohydraulics transients in reference with the thermal shock; b-) The local distribution of temperatures in the downcomer and the heat transference coefficients from the RPV wall to the fluid, are determined; c-) The fracture mechanical analysis. These three stages are included in this work: Results with the thermohydraulics code Relap5/mod.3, are obtained, for a LOCA scenario in the hot leg of the cooling System of the Primary System of the CAN-I reactor. The method used in obtaining results is described. A study on the basis of lumped parameters of the local evolutions of the temperature of the flow is made, in the downcomer of the reactor pressure vessel. The purpose of this study is to determine how the intensification of the stress coefficient, varies in function of the emergency injected water during the thermohydraulic transients that take place under the imposed conditions in the postulated scene. Specially, it is considered a 50 cm 2 break, located in the neighborhoods of the pressurized with the corresponding hot leg connection. This size is considered like the most critical. The method used to obtain the results is described. The fracture mechanical analysis is made. From the obtained results we confirmed that we have a simple tool of easy application in order to analyze phenomena of the type PTS in the postulated scenes by break in the cold and hot legs of the primary system. This methodology of calculus is completely independent of the used ones by the Nucleoelectrica Argentina S.A. (NASA) in the analysis of the PTS phenomena in the CAN-I. The results obtained with the adopted

  9. Clinical performance of the Prostate Health Index (PHI) for the prediction of prostate cancer in obese men: data from the PROMEtheuS project, a multicentre European prospective study.

    Abrate, Alberto; Lazzeri, Massimo; Lughezzani, Giovanni; Buffi, Nicolòmaria; Bini, Vittorio; Haese, Alexander; de la Taille, Alexandre; McNicholas, Thomas; Redorta, Joan Palou; Gadda, Giulio M; Lista, Giuliana; Kinzikeeva, Ella; Fossati, Nicola; Larcher, Alessandro; Dell'Oglio, Paolo; Mistretta, Francesco; Freschi, Massimo; Guazzoni, Giorgio

    2015-04-01

    To test serum prostate-specific antigen (PSA) isoform [-2]proPSA (p2PSA), p2PSA/free PSA (%p2PSA) and Prostate Health Index (PHI) accuracy in predicting prostate cancer in obese men and to test whether PHI is more accurate than PSA in predicting prostate cancer in obese patients. The analysis consisted of a nested case-control study from the pro-PSA Multicentric European Study (PROMEtheuS) project. The study is registered at http://www.controlled-trials.com/ISRCTN04707454. The primary outcome was to test sensitivity, specificity and accuracy (clinical validity) of serum p2PSA, %p2PSA and PHI, in determining prostate cancer at prostate biopsy in obese men [body mass index (BMI) ≥30 kg/m(2) ], compared with total PSA (tPSA), free PSA (fPSA) and fPSA/tPSA ratio (%fPSA). The number of avoidable prostate biopsies (clinical utility) was also assessed. Multivariable logistic regression models were complemented by predictive accuracy analysis and decision-curve analysis. Of the 965 patients, 383 (39.7%) were normal weight (BMI PHI were significantly higher, and %fPSA significantly lower in patients with prostate cancer (P PHI significantly increased accuracy of the base multivariable model by 8.8% (P = 0.007). At a PHI threshold of 35.7, 46 (32.4%) biopsies could have been avoided. In obese patients, PHI is significantly more accurate than current tests in predicting prostate cancer. © 2014 The Authors. BJU International © 2014 BJU International.

  10. Radiation- and pair-loaded shocks

    Lyutikov, Maxim

    2018-06-01

    We consider the structure of mildly relativistic shocks in dense media, taking into account the radiation and pair loading, and diffusive radiation energy transfer within the flow. For increasing shock velocity (increasing post-shock temperature), the first important effect is the efficient energy redistribution by radiation within the shock that leads to the appearance of an isothermal jump, whereby the flow reaches the final state through a discontinuous isothermal transition. The isothermal jump, on scales much smaller than the photon diffusion length, consists of a weak shock and a quick relaxation to the isothermal conditions. Highly radiation-dominated shocks do not form isothermal jump. Pair production can mildly increase the overall shock compression ratio to ≈10 (4 for matter-dominated shocks and 7 of the radiation-dominated shocks).

  11. Shock diffraction in alumina powder

    Venz, G.; Killen, P.D.; Page, N.W.

    1996-01-01

    In order to produce complex shaped components by dynamic compaction of ceramic powders detailed knowledge of their response under shock loading conditions is required. This work attempts to provide data on release effects and shock attenuation in 1 μm and 5 μm α-alumina powders which were compacted to between 85 % and 95 % of the solid phase density by the impact of high velocity steel projectiles. As in previous work, the powder was loaded into large cylindrical dies with horizontal marker layers of a contrasting coloured powder to provide a record of powder displacement in the recovered specimens. After recovery and infiltration with a thermosetting resin the specimens were sectioned and polished to reveal the structure formed by the passage of the projectile and shock wave. Results indicate that the shock pressures generated were of the order of 0.5 to 1.4 GPa and higher, with shock velocities and sound speeds in the ranges 650 to 800 m/s and 350 to 400 m/s respectively

  12. Transient shocks beyond the heliopause

    Fermo, R L; Pogorelov, N V; Burlaga, L F

    2015-01-01

    The heliopause is a rich, dynamic surface affected by the time-dependent solar wind. Stream interactions due to coronal mass ejections (CMEs), corotating interaction regions (CIRs), and other transient phenomena are known to merge producing global merged interaction regions (GMIRs). Numerical simulations of the solar wind interaction with the local interstellar medium (LISM) show that GMIRs, as well other time-dependent structures in the solar wind, may produce compression/rarefaction waves and shocks in the LISM behind the heliopause. These shocks may initiate wave activity observed by the Voyager spacecraft. The magnetometer onboard Voyager 1 indeed observed a few structures that may be interpreted as shocks. We present numerical simulations of such shocks in the year of 2000, when both Voyager spacecraft were in the supersonic solar wind region, and in 2012, when Voyager 1 observed traveling shocks. In the former case, Voyager observations themselves provide time- dependent boundary conditions in the solar wind. In the latter case, we use OMNI data at 1 AU to analyze the plasma and magnetic field behavior after Voyager 1 crossed the heliospheric boundary. Numerical results are compared with spacecraft observations. (paper)

  13. The relationship between global oil price shocks and China's output: A time-varying analysis

    Cross, Jamie; Nguyen, Bao H.

    2017-01-01

    We employ a class of time-varying Bayesian vector autoregressive (VAR) models on new standard dataset of China's GDP constructed by to examine the relationship between China's economic growth and global oil market fluctuations between 1992Q1 and 2015Q3. We find that: (1) the time varying parameter VAR with stochastic volatility provides a better fit as compared to it's constant counterparts; (2) the impacts of intertemporal global oil price shocks on China's output are often small and temporary in nature; (3) oil supply and specific oil demand shocks generally produce negative movements in China's GDP growth whilst oil demand shocks tend to have positive effects; (4) domestic output shocks have no significant impact on price or quantity movements within the global oil market. The results are generally robust to three commonly employed indicators of global economic activity: Kilian's global real economic activity index, the metal price index and the global industrial production index, and two alternative oil price metrics: the US refiners' acquisition cost for imported crude oil and the West Texas Intermediate price of crude oil. - Highlights: • A class of time-varying BVARs is used to examine the relationship between China's economic growth and global oil market fluctuations. • The impacts of intertemporal global oil price shocks on China's output are often small and temporary in nature. • Oil supply and specific oil demand shocks generally produce negative movements in China's GDP growth while oil demand shocks tend to have positive effects. • Domestic output shocks have no significant impact on price or quantity movements within the global oil market.

  14. Energetic ion acceleration at collisionless shocks

    Decker, R. B.; Vlahos, L.

    1985-01-01

    An example is presented from a test particle simulation designed to study ion acceleration at oblique turbulent shocks. For conditions appropriate at interplanetary shocks near 1 AU, it is found that a shock with theta sub B n = 60 deg is capable of producing an energy spectrum extending from 10 keV to approx. 1 MeV in approx 1 hour. In this case total energy gains result primarily from several separate episodes of shock drift acceleration, each of which occurs when particles are scattered back to the shock by magnetic fluctuations in the shock vicinity.

  15. Energetic ion acceleration at collisionless shocks

    Decker, R.B.; Vlahos, L.

    1985-01-01

    An example is presented from a test particle simulation designed to study ion acceleration at oblique turbulent shocks. For conditions appropriate at interplanetary shocks near 1 AU, it is found that a shock with theta sub B n = 60 deg is capable of producing an energy spectrum extending from 10 keV to approx 1 MeV in approx 1 hour. In this case total energy gains result primarily from several separate episodes of shock drift acceleration, each of which occurs when particles are scattered back to the shock by magnetic fluctuations in the shock vicinity

  16. Why the Nature of Oil Shocks Matters

    Archanskaia, Elizaveta; Hubert, Paul; Creel, Jerome

    2009-03-01

    This article studies the impact of oil shocks on the macro-economy in two ways insofar unexploited in the literature. The analysis is conducted at the global level, and it explicitly accounts for the potentially changing nature of oil shocks. Based on an original world GDP series and a grouping of oil shocks according to their nature, we find that oil supply shocks negatively impact world growth, contrary to oil demand shocks, pro-cyclical in their nature. This result is robust at the national level for the US. Furthermore, endogenous monetary policy is shown to have no counter-cyclical effects in the context of an oil demand shock. (authors)

  17. MHD intermediate shock discontinuities: Pt. 1

    Kennel, C.F.; Blandford, R.D.; Coppi, P.

    1989-01-01

    Recent numerical investigations have focused attention once more on the role of intermediate shocks in MHD. Four types of intermediate shock are identified using a graphical representation of the MHD Rankine-Hugoniot conditions. This same representation can be used to exhibit the close relationship of intermediate shocks to switch-on shocks and rotational discontinuities. The conditions under which intermediate discontinuities can be found are elucidated. The variations in velocity, pressure, entropy and magnetic-field jumps with upstream parameters in intermediate shocks are exhibited graphically. The evolutionary arguments traditionally advanced against intermediate shocks may fail because the equations of classical MHD are not strictly hyperbolic. (author)

  18. Shock waves in weakly compressed granular media.

    van den Wildenberg, Siet; van Loo, Rogier; van Hecke, Martin

    2013-11-22

    We experimentally probe nonlinear wave propagation in weakly compressed granular media and observe a crossover from quasilinear sound waves at low impact to shock waves at high impact. We show that this crossover impact grows with the confining pressure P0, whereas the shock wave speed is independent of P0-two hallmarks of granular shocks predicted recently. The shocks exhibit surprising power law attenuation, which we model with a logarithmic law implying that shock dissipation is weak and qualitatively different from other granular dissipation mechanisms. We show that elastic and potential energy balance in the leading part of the shocks.

  19. Shock, diaschisis and von Monakow

    Eliasz Engelhardt

    2013-07-01

    Full Text Available The concept of shock apparently emerged in the middle of the 18th century (Whyett as an occurrence observed experimentally after spinal cord transection, and identified as "shock" phenomenon one century later (Hall. The concept was extended (Brown-Séquard and it was suggested that brain lesions caused functional rupture in regions distant from the injured one ("action à distance". The term "diaschisis" (von Monakow, proposed as a new modality of shock, had its concept broadened, underpinned by observations of patients, aiming at distinguishing between symptoms of focal brain lesions and transitory effects they produced, attributable to depression of distant parts of the brain connected to the injured area. Presently, diaschisis is related mainly to cerebrovascular lesions and classified according to the connection fibers involved, as proposed by von Monakow. Depression of metabolism and blood flow in regions anatomically separated, but related by connections with the lesion, allows observing diaschisis with neuroimaging.

  20. Shock compression of geological materials

    Kirk, S; Braithwaite, C; Williamson, D; Jardine, A

    2014-01-01

    Understanding the shock compression of geological materials is important for many applications, and is particularly important to the mining industry. During blast mining the response to shock loading determines the wave propagation speed and resulting fragmentation of the rock. The present work has studied the Hugoniot of two geological materials; Lake Quarry Granite and Gosford Sandstone. For samples of these materials, the composition was characterised in detail. The Hugoniot of Lake Quarry Granite was predicted from this information as the material is fully dense and was found to be in good agreement with the measured Hugoniot. Gosford Sandstone is porous and undergoes compaction during shock loading. Such behaviour is similar to other granular material and we show how it can be described using a P-a compaction model.

  1. Shock compression of simulated adobe

    Braithwaite, C. H.; Church, P. D.; Gould, P. J.; Stewart, B.; Jardine, A. P.

    2017-01-01

    A series of plate impact experiments were conducted to investigate the shock response of a simulant for adobe, a traditional form of building material widely used around the world. Air dried bricks were sourced from the London brick company, dry machined and impacted at a range of velocities in a single stage gas gun. The shock Hugoniot was determined (Us =2.26up+0.37) as well as release information. The material was found to behave in a manner which was similar to that of loose sand and considerably less stiff than a weak porous sandstone. The effect of any cementing of the grains was examined by shocking powdered samples contained within a cell arrangement.

  2. Shock Initiation of Damaged Explosives

    Chidester, S K; Vandersall, K S; Tarver, C M

    2009-10-22

    Explosive and propellant charges are subjected to various mechanical and thermal insults that can increase their sensitivity over the course of their lifetimes. To quantify this effect, shock initiation experiments were performed on mechanically and thermally damaged LX-04 (85% HMX, 15% Viton by weight) and PBX 9502 (95% TATB, 5% Kel-F by weight) to obtain in-situ manganin pressure gauge data and run distances to detonation at various shock pressures. We report the behavior of the HMX-based explosive LX-04 that was damaged mechanically by applying a compressive load of 600 psi for 20,000 cycles, thus creating many small narrow cracks, or by cutting wedge shaped parts that were then loosely reassembled, thus creating a few large cracks. The thermally damaged LX-04 charges were heated to 190 C for long enough for the beta to delta solid - solid phase transition to occur, and then cooled to ambient temperature. Mechanically damaged LX-04 exhibited only slightly increased shock sensitivity, while thermally damaged LX-04 was much more shock sensitive. Similarly, the insensitive explosive PBX 9502 was mechanically damaged using the same two techniques. Since PBX 9502 does not undergo a solid - solid phase transition but does undergo irreversible or 'rachet' growth when thermally cycled, thermal damage to PBX 9502 was induced by this procedure. As for LX-04, the thermally damaged PBX 9502 demonstrated a greater shock sensitivity than mechanically damaged PBX 9502. The Ignition and Growth reactive flow model calculated the increased sensitivities by igniting more damaged LX-04 and PBX 9502 near the shock front based on the measured densities (porosities) of the damaged charges.

  3. Comparison of three methods for the estimation of cross-shock electric potential using Cluster data

    A. P. Dimmock

    2011-05-01

    Full Text Available Cluster four point measurements provide a comprehensive dataset for the separation of temporal and spatial variations, which is crucial for the calculation of the cross shock electrostatic potential using electric field measurements. While Cluster is probably the most suited among present and past spacecraft missions to provide such a separation at the terrestrial bow shock, it is far from ideal for a study of the cross shock potential, since only 2 components of the electric field are measured in the spacecraft spin plane. The present paper is devoted to the comparison of 3 different techniques that can be used to estimate the potential with this limitation. The first technique is the estimate taking only into account the projection of the measured components onto the shock normal. The second uses the ideal MHD condition E·B = 0 to estimate the third electric field component. The last method is based on the structure of the electric field in the Normal Incidence Frame (NIF for which only the potential component along the shock normal and the motional electric field exist. All 3 approaches are used to estimate the potential for a single crossing of the terrestrial bow shock that took place on the 31 March 2001. Surprisingly all three methods lead to the same order of magnitude for the cross shock potential. It is argued that the third method must lead to more reliable results. The effect of the shock normal inaccuracy is investigated for this particular shock crossing. The resulting electrostatic potential appears too high in comparison with the theoretical results for low Mach number shocks. This shows the variability of the potential, interpreted in the frame of the non-stationary shock model.

  4. Shock compaction of molybdenum powder

    Ahrens, T. J.; Kostka, D.; Vreeland, T., Jr.; Schwarz, R. B.; Kasiraj, P.

    1983-01-01

    Shock recovery experiments which were carried out in the 9 to 12 GPa range on 1.4 distension Mo and appear adequate to compact to full density ( 45 (SIGMA)m) powders were examined. The stress levels, however, are below those calculated to be from 100 to approx. 22 GPa which a frictional heating model predicts are required to consolidate approx. 10 to 50 (SIGMA)m particles. The model predicts that powders that have a distension of m=1.6 shock pressures of 14 to 72 GPa are required to consolidate Mo powders in the 50 to 10 (SIGMA)m range.

  5. Cation disorder in shocked orthopyroxene.

    Dundon, R. W.; Hafner, S. S.

    1971-01-01

    The study of cation distributions over nonequivalent lattice sites in minerals may reveal information on the history of temperature and pressure in rocks. Chemically homogeneous orthopyroxene specimens were shocked under well-controlled conditions in the laboratory in order to provide a basis for the interpretation of more complex natural materials. As a result of the investigation it is concluded that the distribution of magnesium and iron over the M1 and M2 positions in Bamle enstatite shocked at 1 megabar is highly disordered. It corresponds to an equilibrium distribution of at least 1000 C.

  6. Sepsis and Septic Shock Strategies.

    Armstrong, Bracken A; Betzold, Richard D; May, Addison K

    2017-12-01

    Three therapeutic principles most substantially improve organ dysfunction and survival in sepsis: early, appropriate antimicrobial therapy; restoration of adequate cellular perfusion; timely source control. The new definitions of sepsis and septic shock reflect the inadequate sensitivity, specify, and lack of prognostication of systemic inflammatory response syndrome criteria. Sequential (sepsis-related) organ failure assessment more effectively prognosticates in sepsis and critical illness. Inadequate cellular perfusion accelerates injury and reestablishing perfusion limits injury. Multiple organ systems are affected by sepsis and septic shock and an evidence-based multipronged approach to systems-based therapy in critical illness results in improve outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Shock/shock interactions between bodies and wings

    Gaoxiang XIANG

    2018-02-01

    Full Text Available This paper examines the Shock/Shock Interactions (SSI between the body and wing of aircraft in supersonic flows. The body is simplified to a flat wedge and the wing is assumed to be a sharp wing. The theoretical spatial dimension reduction method, which transforms the 3D problem into a 2D one, is used to analyze the SSI between the body and wing. The temperature and pressure behind the Mach stem induced by the wing and body are obtained, and the wave configurations in the corner are determined. Numerical validations are conducted by solving the inviscid Euler equations in 3D with a Non-oscillatory and Non-free-parameters Dissipative (NND finite difference scheme. Good agreements between the theoretical and numerical results are obtained. Additionally, the effects of the wedge angle and sweep angle on wave configurations and flow field are considered numerically and theoretically. The influences of wedge angle are significant, whereas the effects of sweep angle on wave configurations are negligible. This paper provides useful information for the design and thermal protection of aircraft in supersonic and hypersonic flows. Keywords: Body and wing, Flow field, Hypersonic flow, Shock/shock interaction, Wave configurations

  8. Shock ignition of high gain inertial fusion capsules

    Schurtz, G.; Ribeyre, X.; Lebel, E.; Casner, A.

    2010-01-01

    the theoretical approach of SI, and Lafon et al. established its gain curves using an extension of the Rosen Lindl model. The efficiency of shock ignition comes from the fact that, unlike conventional central ignition, the final fuel assembly is not isobaric, i.e., the low density hot spot pressure significantly exceeds the pressure of the surrounding cold dense fuel. This high hot spot pressure is obtained from two pressure amplification stages: the first amplification mechanism is spherical convergence. A converging shock increases its strength as C 0.9 where C is the shock convergence ratio. A second amplification stage occurs when the ignition shock collides with the outward directed shock that results from the shell stagnation at target centre. Under optimal matching conditions, shock collision produces a x 6 amplification of pressure. We discuss in the presentation the conditions for the obtention of optimal pressure amplification, at first by studying the ignition window in the space spanned by laser power and launching time, and secondly by modelling the relation ship between the laser intensity required for shock production and the implosion velocity. This latter study indicates a sensible safety trade off using a 250 km/s implosion velocity and a laser spike of ∼ 5 x 10 15 W/cm 2 for the shock production. First kinetic calculations and implosion experiments indicate that laser plasma interaction in the regime of shock ignition may remain under control, provided that the SRS generated hot electrons energy stay below 80 keV. Shock Ignition has been proposed as the baseline of the HiPER project and shock ignition experiments have been proposed on the National Ignition Facility with gains expected between 60 and 100 at laser energies below 500 kJ. Acknowledgments. This work is partly supported by the Aquitaine Region Council.

  9. Flash photolysis-shock tube studies

    Michael, J.V. [Argonne National Laboratory, IL (United States)

    1993-12-01

    Even though this project in the past has concentrated on the measurement of thermal bimolecular reactions of atomic species with stable molecules by the flash or laser photolysis-shock tube (FP- or LP-ST) method using atomic resonance absorption spectrometry (ARAS) as the diagnostic technique, during the past year the authors have concentrated on studies of the thermal decompositions of selected chlorocarbon molecules. These studies are necessary if the degradation of chlorine containing organic molecules by incineration are to be understood at the molecular level. Clearly, destruction of these molecules will not only involve abstraction reactions, when possible, but also thermal decomposition followed by secondary reactions of the initially formed atoms and radicals. Studies on the thermal decomposition of CH{sub 3}Cl are complete, and the curve-of-growth for Cl-atom atomic resonance absorption has been determined. The new thermal decomposition studies are similar to those already reported for CH{sub 3}Cl.

  10. Effects of Heat Shock on Photosynthetic Properties, Antioxidant Enzyme Activity, and Downy Mildew of Cucumber (Cucumis sativus L..

    Xiaotao Ding

    Full Text Available Heat shock is considered an abiotic stress for plant growth, but the effects of heat shock on physiological responses of cucumber plant leaves with and without downy mildew disease are still not clear. In this study, cucumber seedlings were exposed to heat shock in greenhouses, and the responses of photosynthetic properties, carbohydrate metabolism, antioxidant enzyme activity, osmolytes, and disease severity index of leaves with or without the downy mildew disease were measured. Results showed that heat shock significantly decreased the net photosynthetic rate, actual photochemical efficiency, photochemical quenching coefficient, and starch content. Heat shock caused an increase in the stomatal conductance, transpiration rate, antioxidant enzyme activities, total soluble sugar content, sucrose content, soluble protein content and proline content for both healthy leaves and downy mildew infected leaves. These results demonstrate that heat shock activated the transpiration pathway to protect the photosystem from damage due to excess energy in cucumber leaves. Potential resistance mechanisms of plants exposed to heat stress may involve higher osmotic regulation capacity related to an increase of total accumulations of soluble sugar, proline and soluble protein, as well as higher antioxidant enzymes activity in stressed leaves. Heat shock reduced downy mildew disease severity index by more than 50%, and clearly alleviated downy mildew development in the greenhouses. These findings indicate that cucumber may have a complex physiological change to resist short-term heat shock, and suppress the development of the downy mildew disease.

  11. Analytical solutions of hypersonic type IV shock - shock interactions

    Frame, Michael John

    An analytical model has been developed to predict the effects of a type IV shock interaction at high Mach numbers. This interaction occurs when an impinging oblique shock wave intersects the most normal portion of a detached bow shock. The flowfield which develops is complicated and contains an embedded jet of supersonic flow, which may be unsteady. The jet impinges on the blunt body surface causing very high pressure and heating loads. Understanding this type of interaction is vital to the designers of cowl lips and leading edges on air- breathing hypersonic vehicles. This analytical model represents the first known attempt at predicting the geometry of the interaction explicitly, without knowing beforehand the jet dimensions, including the length of the transmitted shock where the jet originates. The model uses a hyperbolic equation for the bow shock and by matching mass continuity, flow directions and pressure throughout the flowfield, a prediction of the interaction geometry can be derived. The model has been shown to agree well with the flowfield patterns and properties of experiments and CFD, but the prediction for where the peak pressure is located, and its value, can be significantly in error due to a lack of sophistication in the model of the jet fluid stagnation region. Therefore it is recommended that this region of the flowfield be modeled in more detail and more accurate experimental and CFD measurements be used for validation. However, the analytical model has been shown to be a fast and economic prediction tool, suitable for preliminary design, or for understanding the interactions effects, including the basic physics of the interaction, such as the jet unsteadiness. The model has been used to examine a wide parametric space of possible interactions, including different Mach number, impinging shock strength and location, and cylinder radius. It has also been used to examine the interaction on power-law shaped blunt bodies, a possible candidate for

  12. "Driverless" Shocks in the Interplanetary Medium

    Gopalswamy, N.; Kaiser, M. L.; Lara, A.

    1999-01-01

    Many interplanetary shocks have been detected without an obvious driver behind them. These shocks have been thought to be either blast waves from solar flares or shocks due to sudden increase in solar wind speed caused by interactions between large scale open and closed field lines of the Sun. We investigated this problem using a set of interplanetary shock detected {\\it in situ} by the Wind space craft and tracing their solar origins using low frequency radio data obtained by the Wind/WAVES experiment. For each of these "driverless shocks" we could find a unique coronal mass ejections (CME) event observed by the SOHO (Solar and Heliospheric Observatory) coronagraphs. We also found that these CMEs were ejected at large angles from the Sun-Earth line. It appears that the "driverless shocks" are actually driver shocks, but the drivers were not intercepted by the spacecraft. We conclude that the interplanetary shocks are much more extended than the driving CMEs.

  13. Shock and Vibration. Volume 1, Issue 1

    Pilkey, Walter D

    1994-01-01

    ..., and earthquake engineering. Among the specific areas to be covered are vibration testing and control, vibration condition monitoring and diagnostics, shock hardenings, modal technology, shock testing, data acquisition, fluid...

  14. Initial ISEE magnetometer results: shock observation

    Russell, C.T.

    1979-01-01

    ISEE-1 and -2 magnetic field profiles across 6 terrestrial bow shock and one interplanetary shock are examined. The inteplanetary shock illustrates the behavior of a low Mach number shock. Three examples of low or moderate β, high Mach number, quasi-perpendicular shocks are examined. These did not have upstream waves, but rather had waves growing in the field gradient. Two examples of high β shocks showed little coherence in field variation even though the two vehicles were only a few hundred kilometers apart. The authors present the joint behavior of wave, particle and field data across some of these shocks to show some of the myriad of shock features whose behavior they are now beginning to investigate. (Auth.)

  15. 29th International Symposium on Shock Waves

    Ranjan, Devesh

    2015-01-01

    This proceedings present the results of the 29th International Symposium on Shock Waves (ISSW29) which was held in Madison, Wisconsin, U.S.A., from July 14 to July 19, 2013. It was organized by the Wisconsin Shock Tube Laboratory, which is part of the College of Engineering of the University of Wisconsin-Madison. The ISSW29 focused on the following areas: Blast Waves, Chemically Reactive Flows, Detonation and Combustion,  Facilities, Flow Visualization, Hypersonic Flow, Ignition, Impact and Compaction, Industrial Applications, Magnetohydrodynamics, Medical and Biological Applications, Nozzle Flow, Numerical Methods, Plasmas, Propulsion, Richtmyer-Meshkov Instability, Shock-Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shock Waves in Condensed Matter, Shock Waves in Multiphase Flow, as well as Shock Waves in Rarefield Flow. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 29 and individuals interes...

  16. Inferior vena cava obstruction and shock

    Megri Mohammed

    2018-01-01

    Full Text Available Shock is one of the most challenging life-threatening conditions with high mortality and morbidity; the outcomes are highly dependent on the early detection and management of the condition. Septic shock is the most common type of shock in the Intensive Care Unit. While not as common as other subsets of shock, obstructive shock is a significant subtype due to well defined mechanical and pathological causes, including tension pneumothorax, massive pulmonary embolism, and cardiac tamponade. We are presenting a patient with obstructive shock due to inferior vena cava obstruction secondary to extensive deep venous thrombosis. Chance of survival from obstructive shock in our patient was small; however, there was complete and immediate recovery after treatment of the obstruction on recognizing the affected vessels. This case alerts the practicing intensivist and the emergency medicine physician to consider occlusion of the great vessels other than the pulmonary artery or aorta as causes of obstructive shock.

  17. Shock dynamics in layered periodic media

    Ketcheson, David I.

    2012-01-01

    Solutions of constant-coeffcient nonlinear hyperbolic PDEs generically develop shocks, even if the initial data is smooth. Solutions of hyperbolic PDEs with variable coeffcients can behave very differently. We investigate formation and stability of shock waves in a one-dimensional periodic layered medium by a computational study of time-reversibility and entropy evolution. We find that periodic layered media tend to inhibit shock formation. For small initial conditions and large impedance variation, no shock formation is detected even after times much greater than the time of shock formation in a homogeneous medium. Furthermore, weak shocks are observed to be dynamically unstable in the sense that they do not lead to significant long-term entropy decay. We propose a characteristic condition for admissibility of shocks in heterogeneous media that generalizes the classical Lax entropy condition and accurately predicts the formation or absence of shocks in these media.

  18. Astrophysical radiative shocks: From modeling to laboratory experiments

    Gonzales, N.; Stehlé, C.; Audit, E.; Busquet, M.; Rus, Bedřich; Thais, F.; Acef, O.; Barroso, P.; Bar-Shalom, A.; Bauduin, D.; Kozlová, Michaela; Lery, T.; Madouri, A.; Mocek, Tomáš; Polan, Jiří

    2006-01-01

    Roč. 24, - (2006), s. 535-540 ISSN 0263-0346 EU Projects: European Commission(XE) 506350 - LASERLAB-EUROPE; European Commission(XE) 5592 - JETSET Grant - others:CNRS(FR) PNPS Institutional research plan: CEZ:AV0Z10100523 Keywords : laboratory astrophysics * laser plasmas * radiative shock waves * radiative transfer Subject RIV: BH - Optics, Masers, Lasers Impact factor: 3.958, year: 2006

  19. Converging cylindrical shocks in ideal magnetohydrodynamics

    Pullin, D. I.; Mostert, W.; Wheatley, V.; Samtaney, R.

    2014-01-01

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R=√(μ 0 /p 0 ) I/(2 π) where I is the current, μ 0 is the permeability, and p 0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field

  20. Converging cylindrical shocks in ideal magnetohydrodynamics

    Pullin, D. I.

    2014-09-01

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R = √μ0/p0 I/(2π) where I is the current, μ0 is the permeability, and p0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field then

  1. Converging cylindrical shocks in ideal magnetohydrodynamics

    Pullin, D. I.; Mostert, W.; Wheatley, V.; Samtaney, Ravi

    2014-01-01

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R = √μ0/p0 I/(2π) where I is the current, μ0 is the permeability, and p0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field then

  2. Converging cylindrical shocks in ideal magnetohydrodynamics

    Pullin, D. I. [Graduate Aerospace Laboratories, California Institute of Technology, Pasadena, California 91125 (United States); Mostert, W.; Wheatley, V. [School of Mechanical and Mining Engineering, University of Queensland, Queensland 4072 (Australia); Samtaney, R. [Mechanical Engineering, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal (Saudi Arabia)

    2014-09-15

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R=√(μ{sub 0}/p{sub 0}) I/(2 π) where I is the current, μ{sub 0} is the permeability, and p{sub 0} is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The

  3. Entropy jump across an inviscid shock wave

    Salas, Manuel D.; Iollo, Angelo

    1995-01-01

    The shock jump conditions for the Euler equations in their primitive form are derived by using generalized functions. The shock profiles for specific volume, speed, and pressure are shown to be the same, however density has a different shock profile. Careful study of the equations that govern the entropy shows that the inviscid entropy profile has a local maximum within the shock layer. We demonstrate that because of this phenomenon, the entropy, propagation equation cannot be used as a conservation law.

  4. Collisionless Electrostatic Shock Modeling and Simulation

    2016-10-21

    equations with piston -like boundary conditions gives a solution for the shock behavior. • Assumes cold upstream ions, therefore neglecting shock...temperature ratio (>10) – Wave Train Wavelength – Shock-Front Mach Number – Reflected Ion Beam Velocity Gathering Experiment Data – Double Plasma Device...experimental shock data. • Inconsistencies in published 1969 double -plasma device data hampered validation. Future Work: Extension to Moderately

  5. Shock waves in gas and plasma

    Niu, K.

    1996-01-01

    A shock wave is a discontinuous surface that connects supersonic flow with subsonic flow. After a shock wave, flow velocity is reduced, and pressure and temperature increase; entropy especially increases across a shock wave. Therefore, flow is in nonequilibrium, and irreversible processes occur inside the shock layer. The thickness of a shock wave in neutral gas is of the order of the mean free path of the fluid particle. A shock wave also appears in magnetized plasma. Provided that when the plasma flow is parallel to the magnetic field, a shock wave appears if the governing equation for velocity potential is in hyperbolic type in relation with the Mach number and the Alfven number. When the flow is perpendicular to the magnetic field, the Maxwell stress, in addition to the pressure, plays a role in the shock wave in plasma. When the plasma temperature is so high, as the plasma becomes collision-free, another type of shock wave appears. In a collision-free shock wave, gyromotions of electrons around the magnetic field lines cause the shock formation instead of collisions in a collision-dominant plasma or neutral gas. Regardless of a collision-dominant or collision-free shock wave, the fluid that passes through the shock wave is heated in addition to being compressed. In inertial confinement fusion, the fuel must be compressed. Really, implosion motion performs fuel compression. A shock wave, appearing in the process of implosion, compresses the fuel. The shock wave, however, heats the fuel more intensively, and it makes it difficult to compress the fuel further because high temperatures invite high pressure. Adiabatic compression of the fuel is the desired result during the implosion, without the formation of a shock wave. (Author)

  6. Electric shock and electrical fire specialty

    2011-02-01

    This book deals with electric shock and electrical fire, which is made up seven chapters. It describes of special measurement for electric shock and electrical fire. It mentions concretely about electrical fire analysis and precautionary measurement, electrical shock analysis cases, occurrence of static electricity and measurement, gas accident, analysis of equipment accident and precautionary measurement. The book is published to educate the measurement on electric shock and electrical fire by electrical safety technology education center in Korea Electrical Safety Corporation.

  7. Focused tandem shock waves in water and their potential application in cancer treatment

    Lukeš, Petr; Šunka, Pavel; Hoffer, Petr; Stelmashuk, Vitaliy; Poučková, P.; Zadinová, M.; Zeman, J.; Dibdiak, L.; Kolářová, H.; Tománková, K.; Binder, S.; Beneš, J.

    2014-01-01

    Roč. 24, č. 1 (2014), s. 51-57 ISSN 0938-1287. [International Symposium on Shock Waves/28./. Manchester, 17.07.2011-22.07.2011] R&D Projects: GA ČR GA202/09/1151 Institutional support: RVO:61389021 Keywords : focused shock waves * underwater discharge * cancer treatment Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.885, year: 2014

  8. Shock pressure induced by 0.44 mu m laser radiation on aluminum targets

    Batani, D.; Stabile, H.; Ravasio, A.; Desai, T.; Lucchini, G.; Strati, F.; Ullschmied, Jiří; Krouský, Eduard; Skála, Jiří; Králiková, Božena; Pfeifer, Miroslav; Kadlec, Christelle; Mocek, Tomáš; Präg R., Ansgar; Nishimura, H.; Ochi, Y.; Kilpio, A.; Shashkov, E.; Stuchebrukhov, I.; Vovchenko, V.; Krasuyk, I.

    2003-01-01

    Roč. 21, č. 4 (2003), s. 481-487 ISSN 0263-0346 R&D Projects: GA MŠk LN00A100 Grant - others:HPRI-CT(XX) 1999-00053 Institutional research plan: CEZ:AV0Z2043910 Keywords : rear target luminosity, shock pressure, shock waves Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.646, year: 2003

  9. Comparative architecture of octahedral protein cages. I. Indexed enclosing forms

    Janner, A.

    2008-07-01

    The architecture of four protein cages (bacterio ferritin, human mitochondrial ferritin, sulfur oxygenase reductase and small heat-shock protein) are compared top-to-bottom, starting from polyhedra with vertices at cubic lattice points enclosing the cage down to indexed polyhedral forms of single monomers.

  10. Prenatal temperature shocks reduce cooperation

    Duchoslav, Jan

    2017-01-01

    Climate change has not only led to a sustained rise in mean global temperature over the past decades, but also increased the frequency of extreme weather events. This paper explores the effect of temperature shocks in utero on later-life taste for cooperation. Using historical climate data combined

  11. Shock Incarceration: Rehabilitation or Retribution?

    MacKenzie, Doris Layton; And Others

    1989-01-01

    Reviews Louisiana's shock incarceration program used as alternative to standard prison incarceration. Program involves short period of imprisonment in a "boot camp" type atmosphere followed by three phases of intensive parole supervision. Examines the program in regard to its rehabilitative potential and compares program elements to…

  12. Shock Mounting for Heavy Machines

    Thompson, A. R.

    1984-01-01

    Elastomeric bearings eliminate extraneous forces. Rocket thrust transmitted from motor to load cells via support that absorbs extraneous forces so they do not affect accuracy of thrust measurements. Adapter spoked cone fits over forward end of rocket motor. Shock mounting developed for rocket engines under test used as support for heavy machines, bridges, or towers.

  13. 2-Shock layered tuning campaign

    Masse, Laurent; Dittrich, T.; Khan, S.; Kyrala, G.; Ma, T.; MacLaren, S.; Ralph, J.; Salmonson, J.; Tipton, R.; Los Alamos Natl Lab Team; Lawrence Livermore Natl Lab Team

    2016-10-01

    The 2-Shock platform has been developed to maintain shell sphericity throughout the compression phase of an indirect-drive target implosion and produce a stagnating hot spot in a quasi 1D-like manner. A sub-scale, 1700 _m outer diameter, and thick, 200 _m, uniformly Silicon doped, gas-filled plastic capsule is driven inside a nominal size 5750 _m diameter ignition hohlraum. The hohlraum fill is near vacuum to reduce back-scatter and improve laser/drive coupling. A two-shock pulse of about 1 MJ of laser energy drives the capsule. The thick capsule prevents ablation front feed-through to the imploded core. This platform has demonstrated its efficiency to tune a predictable and reproducible 1-D implosion with a nearly round shape. It has been shown that the high foot performance was dominated by the local defect growth due to the ablation front instability and by the hohlraum radiation asymmetries. The idea here is to take advantage of this 2-Shock platform to design a 1D-like layered implosion and eliminates the deleterious effects of radiation asymmetries and ablation front instability growth. We present the design work and our first experimental results of this near one-dimensional 2-Shock layered design. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344.

  14. Interstellar turbulence and shock waves

    Bykov, A.M.

    1982-01-01

    Random deflections of shock fronts propagated through the turbulent interstellar medium can produce the strong electro-density fluctuations on scales l> or approx. =10 13 cm inferred from pulsar radio scintillations. The development of turbulence in the hot-phase ISM is discussed

  15. Nonlinearity, Conservation Law and Shocks

    However, genuine nonlinearity is always present in an ideal gas. The conservation form of the equation (25) brings in shocks which cut off the growing part of the amplitUde as shown in. Figure 15. Acknowledgements. The author sincerely thanks the two referees whose valuable comments led to an improvement of the ...

  16. Model for Shock Wave Chaos

    Kasimov, Aslan R.

    2013-03-08

    We propose the following model equation, ut+1/2(u2−uus)x=f(x,us) that predicts chaotic shock waves, similar to those in detonations in chemically reacting mixtures. The equation is given on the half line, x<0, and the shock is located at x=0 for any t≥0. Here, us(t) is the shock state and the source term f is taken to mimic the chemical energy release in detonations. This equation retains the essential physics needed to reproduce many properties of detonations in gaseous reactive mixtures: steady traveling wave solutions, instability of such solutions, and the onset of chaos. Our model is the first (to our knowledge) to describe chaos in shock waves by a scalar first-order partial differential equation. The chaos arises in the equation thanks to an interplay between the nonlinearity of the inviscid Burgers equation and a novel forcing term that is nonlocal in nature and has deep physical roots in reactive Euler equations.

  17. EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY AS ...

    Objective To evaluate extracorporeal shock wave lithotripsy (ESWL) as a monotherapy for urolithiasis in patients with solitary kidney and to determine the factors that may affect its results. Patients and Methods Using the Dornier MFL 5000 lithotriptor, 106 patients with solitary kidney (80 men and 26 women) were treated for ...

  18. Shock formation within sonoluminescence bubbles

    Vuong, V.Q.; Szeri, A.J.; Young, D.A.

    1999-01-01

    A strong case has been made by several authors that sharp, spherically symmetric shocks converging on the center of a spherical bubble driven by a strong acoustic field give rise to rapid compression and heating that produces the brief flash of light known as sonoluminescence. The formation of such shocks is considered. It is found that, although at the main collapse the bubble wall does indeed launch an inwardly-traveling compression wave, and although the subsequent reflection of the wave at the bubble center produces a very rapid temperature peak, the wave is prevented from steepening into a sharp shock by an adverse gradient in the sound speed caused by heat transfer. It is shown that the mathematical characteristics of the flow can be prevented from accumulating into a shock front by this adverse sound speed gradient. A range of results is presented for a variety of bubble ambient radii and sound field amplitudes suggested by experiments. The time scale of the peak temperature in the bubble is set by the dynamics of the compression wave: this is typically in the range 100 - 300 ps (FWHM) in concert with recent measurements of the sonoluminescence pulse width. copyright 1999 American Institute of Physics

  19. Model for Shock Wave Chaos

    Kasimov, Aslan R.; Faria, Luiz; Rosales, Rodolfo R.

    2013-01-01

    : steady traveling wave solutions, instability of such solutions, and the onset of chaos. Our model is the first (to our knowledge) to describe chaos in shock waves by a scalar first-order partial differential equation. The chaos arises in the equation

  20. Depressed left ventricular performance. Response to volume infusion in patients with sepsis and septic shock

    Ognibene, F.P.; Parker, M.M.; Natanson, C.; Shelhamer, J.H.; Parrillo, J.E.

    1988-01-01

    Volume infusion, to increase preload and to enhance ventricular performance, is accepted as initial management of septic shock. Recent evidence has demonstrated depressed myocardial function in human septic shock. We analyzed left ventricular performance during volume infusion using serial data from simultaneously obtained pulmonary artery catheter hemodynamic measurements and radionuclide cineangiography. Critically ill control subjects (n = 14), patients with sepsis but without shock (n = 21), and patients with septic shock (n = 21) had prevolume infusion hemodynamic measurements determined and received statistically similar volumes of fluid resulting in similar increases in pulmonary capillary wedge pressure. There was a strong trend (p = 0.004) toward less of a change in left ventricular stroke work index (LVSWI) after volume infusion in patients with sepsis and septic shock compared with control subjects. The LVSWI response after volume infusion was significantly less in patients with septic shock when compared with critically ill control subjects (p less than 0.05). These data demonstrate significantly altered ventricular performance, as measured by LVSWI, in response to volume infusion in patients with septic shock

  1. Attentional Bias for Uncertain Cues of Shock in Human Fear Conditioning: Evidence for Attentional Learning Theory

    Stephan Koenig

    2017-05-01

    Full Text Available We conducted a human fear conditioning experiment in which three different color cues were followed by an aversive electric shock on 0, 50, and 100% of the trials, and thus induced low (L, partial (P, and high (H shock expectancy, respectively. The cues differed with respect to the strength of their shock association (L < P < H and the uncertainty of their prediction (L < P > H. During conditioning we measured pupil dilation and ocular fixations to index differences in the attentional processing of the cues. After conditioning, the shock-associated colors were introduced as irrelevant distracters during visual search for a shape target while shocks were no longer administered and we analyzed the cues’ potential to capture and hold overt attention automatically. Our findings suggest that fear conditioning creates an automatic attention bias for the conditioned cues that depends on their correlation with the aversive outcome. This bias was exclusively linked to the strength of the cues’ shock association for the early attentional processing of cues in the visual periphery, but additionally was influenced by the uncertainty of the shock prediction after participants fixated on the cues. These findings are in accord with attentional learning theories that formalize how associative learning shapes automatic attention.

  2. Attentional Bias for Uncertain Cues of Shock in Human Fear Conditioning: Evidence for Attentional Learning Theory

    Koenig, Stephan; Uengoer, Metin; Lachnit, Harald

    2017-01-01

    We conducted a human fear conditioning experiment in which three different color cues were followed by an aversive electric shock on 0, 50, and 100% of the trials, and thus induced low (L), partial (P), and high (H) shock expectancy, respectively. The cues differed with respect to the strength of their shock association (L H). During conditioning we measured pupil dilation and ocular fixations to index differences in the attentional processing of the cues. After conditioning, the shock-associated colors were introduced as irrelevant distracters during visual search for a shape target while shocks were no longer administered and we analyzed the cues’ potential to capture and hold overt attention automatically. Our findings suggest that fear conditioning creates an automatic attention bias for the conditioned cues that depends on their correlation with the aversive outcome. This bias was exclusively linked to the strength of the cues’ shock association for the early attentional processing of cues in the visual periphery, but additionally was influenced by the uncertainty of the shock prediction after participants fixated on the cues. These findings are in accord with attentional learning theories that formalize how associative learning shapes automatic attention. PMID:28588466

  3. Studying shocks in model astrophysical flows

    Chakrabarti, S.K.

    1989-01-01

    We briefly discuss some properties of the shocks in the existing models for quasi two-dimensional astrophysical flows. All of these models which allow the study of shock analytically have some unphysical characteristics due to inherent assumptions made. We propose a hybrid model for a thin flow which has fewer unpleasant features and is suitable for the study of shocks. (author). 5 refs

  4. Shock waves in relativistic nuclear matter, I

    Gleeson, A.M.; Raha, S.

    1979-02-01

    The relativistic Rankine-Hugoniot relations are developed for a 3-dimensional plane shock and a 3-dimensional oblique shock. Using these discontinuity relations together with various equations of state for nuclear matter, the temperatures and the compressibilities attainable by shock compression for a wide range of laboratory kinetic energy of the projectile are calculated. 12 references

  5. The microphysics of collisionless shock waves

    Marcowith, Alexandre; Bret, Antoine; Bykov, Andrei

    2016-01-01

    Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and in astrophysics. They are to be found in a great variety of objects and environments: magnetospheric and heliospheric shocks, supernova remnants, pulsar winds and their nebulæ, active ga...

  6. Performance evaluation of CFRP-rubber shock absorbers

    Lamanna, Giuseppe; Sepe, Raffaele

    2014-05-01

    In the present work a numerical investigation on the energy absorbing capability of dedicated structural components made of a carbon fiber reinforced polymer and an emulsion polymerised styrene butadiene rubber is reported. The shock absorbers are devices designed to absorb large amounts of energy by sacrificing their own structural integrity. Their aim is to cushion the effects of an impact phenomenon with the intent to preserve other structures from global failure or local damaging. Another important role of shock absorbers is reducing the peak of the acceleration showed during an impact phenomenon. This effect is of considerable interest in the case of vehicles to preserve passengers' safety. Static and dynamic numerical results are compared with experimental ones in terms of mean crushing forces, energy and peak crushing. The global performance of the absorbers has been evaluated by referencing to a proposed quality index.

  7. Performance evaluation of CFRP-rubber shock absorbers

    Lamanna, Giuseppe, E-mail: giuseppe.lamanna@unina2.it; Sepe, Raffaele, E-mail: giuseppe.lamanna@unina2.it [Department of Industrial and Information Engineering, Second University of Naples, via Roma, 29 - 81031 Aversa (Italy)

    2014-05-15

    In the present work a numerical investigation on the energy absorbing capability of dedicated structural components made of a carbon fiber reinforced polymer and an emulsion polymerised styrene butadiene rubber is reported. The shock absorbers are devices designed to absorb large amounts of energy by sacrificing their own structural integrity. Their aim is to cushion the effects of an impact phenomenon with the intent to preserve other structures from global failure or local damaging. Another important role of shock absorbers is reducing the peak of the acceleration showed during an impact phenomenon. This effect is of considerable interest in the case of vehicles to preserve passengers’ safety. Static and dynamic numerical results are compared with experimental ones in terms of mean crushing forces, energy and peak crushing. The global performance of the absorbers has been evaluated by referencing to a proposed quality index.

  8. RAPID COSMIC-RAY ACCELERATION AT PERPENDICULAR SHOCKS IN SUPERNOVA REMNANTS

    Takamoto, Makoto; Kirk, John G., E-mail: mtakamoto@eps.s.u-tokyo.ac.jp, E-mail: john.kirk@mpi-hd.mpg.de [Max-Planck-Institut für Kernphysik, Postfach 103980, D-69029 Heidelberg (Germany)

    2015-08-10

    Perpendicular shocks are shown to be rapid particle accelerators that perform optimally when the ratio u{sub s} of the shock speed to the particle speed roughly equals the ratio 1/η of the scattering rate to the gyro frequency. We use analytical methods and Monte-Carlo simulations to solve the kinetic equation that governs the anisotropy generated at these shocks, and find, for ηu{sub s} ≈ 1, that the spectral index softens by unity and the acceleration time increases by a factor of two compared to the standard result of the diffusive shock acceleration theory. These results provide a theoretical basis for the 30 year old conjecture that a supernova exploding into the wind of a Wolf–Rayet star may accelerate protons to an energy exceeding 10{sup 15} eV.

  9. [Extracorporeal shock wave therapy in chronic prostatitis].

    Kul'chavenya, E V; Shevchenko, S Yu; Brizhatyuk, E V

    2016-04-01

    Chronic prostatitis is a prevalent urologic disease, but treatment outcomes are not always satisfactory. As a rule, chronic prostatitis results in chronic pelvic pain syndrome, significantly reducing the patient's quality of life. Open pilot prospective non-comparative study was conducted to test the effectiveness of extracorporeal shock wave therapy (ESWT) using Aries (Dornier) machine in patients with chronic prostatitis (CP) of IIIb category. A total of 27 patients underwent ESWL as monotherapy, 2 times a week for a course of 6 sessions. Exposure settings: 5-6 energy level (by sensation), the frequency of 5 Hz, 2000 pulses per session; each patient received a total energy up to 12000 mJ. per procedure. Treatment results were evaluated using NIH-CPSI (National Institute of Health Chronic Prostatitis Symptom Index) upon completing the 3 week course of 6 treatments and at 1 month after ESWT. Immediately after the ESWT course positive trend was not significant: pain index decreased from 9.1 to 7.9, urinary symptom score remained almost unchanged (4.2 at baseline, 4.1 after treatment), quality of life index also showed a slight improvement, dropping from 7.2 points to 6.0. Total NIH-CPSI score decreased from 20.5 to 18.0. One month post-treatment pain significantly decreased to 3.2 points, the urinary symptom score fell to 2.7 points, the average quality of life score was 3.9 points. ESWT, performed on Aries (Dornier) machine, is highly effective as monotherapy in patients with category IIIb chronic prostatitis.

  10. Permeability enhancement by shock cooling

    Griffiths, Luke; Heap, Michael; Reuschlé, Thierry; Baud, Patrick; Schmittbuhl, Jean

    2015-04-01

    The permeability of an efficient reservoir, e.g. a geothermal reservoir, should be sufficient to permit the circulation of fluids. Generally speaking, permeability decreases over the life cycle of the geothermal system. As a result, is usually necessary to artificially maintain and enhance the natural permeability of these systems. One of the methods of enhancement -- studied here -- is thermal stimulation (injecting cold water at low pressure). This goal of this method is to encourage new thermal cracks within the reservoir host rocks, thereby increasing reservoir permeability. To investigate the development of thermal microcracking in the laboratory we selected two granites: a fine-grained (Garibaldi Grey granite, grain size = 0.5 mm) and a course-grained granite (Lanhelin granite, grain size = 2 mm). Both granites have an initial porosity of about 1%. Our samples were heated to a range of temperatures (100-1000 °C) and were either cooled slowly (1 °C/min) or shock cooled (100 °C/s). A systematic microstructural (2D crack area density, using standard stereological techniques, and 3D BET specific surface area measurements) and rock physical property (porosity, P-wave velocity, uniaxial compressive strength, and permeability) analysis was undertaken to understand the influence of slow and shock cooling on our reservoir granites. Microstructurally, we observe that the 2D crack surface area per unit volume and the specific surface area increase as a result of thermal stressing, and, for the same maximum temperature, crack surface area is higher in the shock cooled samples. This observation is echoed by our rock physical property measurements: we see greater changes for the shock cooled samples. We can conclude that shock cooling is an extremely efficient method of generating thermal microcracks and modifying rock physical properties. Our study highlights that thermal treatments are likely to be an efficient method for the "matrix" permeability enhancement of

  11. Browse Title Index

    Items 401 - 450 of 452 ... Vol 16, No 3 (2015), Shock wave therapy for spastic plantar flexor muscles ... of Acute Promyelocytic Leukemia (AML-M3) Using Karyotyping, ... gene polymorphisms in a sample of Egyptian autistic children, Abstract PDF.

  12. Applications of Shock Wave Research to Developments of Therapeutic Devices.

    Takayama, Kazuyoshi

    2007-06-01

    Underwater shock wave research applied to medicine started in 1980 by exploding micro lead azide pellets in water. Collaboration with urologists in the School of Medicine, Tohoku University at the same time was directed to disintegration of kidney stones by controlling shock waves. We initially proposed a miniature truncated ellipsoidal cavity for generating high-pressures enough to disintegrate the stone but gave up the idea, when encountering the Dornie Systems' invention of an extracorporeal shock wave lithotripter (ESWL). Then we confirmed its effectiveness by using 10 mg silver azide pellets and constructed our own lithotripter, which was officially approved for a clinical use in 1987. Tissue damage during ESWL was attributable to bubble collapse and we convinced it could be done in a controlled fashion. In 1996, we used 160 mJ pulsed Ho:YAG laser beam focusing inside a catheter for shock generation and applied it to the revascularization of cerebral embolism, which is recently expanded to the treatment of pulmonary infarction. Micro water jets discharged in air were so effective to dissect soft tissues preserving small blood vessels. Animal experiments are successfully performed with high frequency water jets driven by an actuator-assisted micro-pump. A metal foil is deformed at high speed by a Q-switched Nd:YAG laser beam loading. We used this technique to project micro-particles or dry drugs attached on its reverse side and extended it to a laser ablation assisted dry drug delivery or DNA introductory system.

  13. Inappropriate shocks in the subcutaneous ICD

    Olde Nordkamp, Louise R A; Brouwer, Tom F; Barr, Craig

    2015-01-01

    shocks have been reported. METHODS: We analyzed the incidence, predictors and management of inappropriate shocks in the EFFORTLESS S-ICD Registry, which collects S-ICD implantation information and follow-up data from clinical centers in Europe and New Zealand. RESULTS: During a follow-up of 21 ± 13...... xyphoid to V6) reduced the risk. Reprogramming or optimization of SVT treatment after the first clinical event of inappropriate shock was successful in preventing further inappropriate shocks for cardiac oversensing and SVT events. CONCLUSIONS: Inappropriate shocks, mainly due to cardiac oversensing...

  14. EJSCREEN Indexes 2015 Public

    U.S. Environmental Protection Agency — There is an EJ Index for each environmental indicator. There are eight EJ Indexes in EJSCREEN reflecting the 8 environmental indicators. The EJ Index names are:...

  15. EJSCREEN Indexes 2016 Public

    U.S. Environmental Protection Agency — There is an EJ Index for each environmental indicator. There are eleven EJ Indexes in EJSCREEN reflecting the 11 environmental indicators. The EJ Index names are:...

  16. Perpendicular relativistic shocks in magnetized pair plasma

    Plotnikov, Illya; Grassi, Anna; Grech, Mickael

    2018-04-01

    Perpendicular relativistic (γ0 = 10) shocks in magnetized pair plasmas are investigated using two dimensional Particle-in-Cell simulations. A systematic survey, from unmagnetized to strongly magnetized shocks, is presented accurately capturing the transition from Weibel-mediated to magnetic-reflection-shaped shocks. This transition is found to occur for upstream flow magnetizations 10-3 10-2, it leaves place to a purely electromagnetic precursor following from the strong emission of electromagnetic waves at the shock front. Particle acceleration is found to be efficient in weakly magnetized perpendicular shocks in agreement with previous works, and is fully suppressed for σ > 10-2. Diffusive Shock Acceleration is observed only in weakly magnetized shocks, while a dominant contribution of Shock Drift Acceleration is evidenced at intermediate magnetizations. The spatial diffusion coefficients are extracted from the simulations allowing for a deeper insight into the self-consistent particle kinematics and scale with the square of the particle energy in weakly magnetized shocks. These results have implications for particle acceleration in the internal shocks of AGN jets and in the termination shocks of Pulsar Wind Nebulae.

  17. The analytical solution of the problem of a shock focusing in a gas for one-dimensional case

    Shestakovskaya, E. S.; Magazov, F. G.

    2018-03-01

    The analytical solution of the problem of an imploding shock wave in the vessel with an impermeable wall is constructed for the cases of planar, cylindrical and spherical symmetry. The negative velocity is set at the vessel boundary. The velocity of cold ideal gas is zero. At the initial time the shock spreads from this point into the center of symmetry. The boundary moves under the particular law which conforms to the movement of the shock. In Euler variables it moves but in Lagrangian variables its trajectory is a vertical line. Equations that determine the structure of the gas flow between the shock front and the boundary as a function of time and the Lagrangian coordinate as well as the dependence of the entropy on the shock wave velocity are obtained. Self-similar coefficients and corresponding critical values of self-similar coordinates were found for a wide range of adiabatic index. The problem is solved for Lagrangian coordinates.

  18. Initial conditions of radiative shock experiments

    Kuranz, C. C.; Drake, R. P.; Krauland, C. M.; Marion, D. C.; Grosskopf, M. J.; Rutter, E.; Torralva, B.; Holloway, J. P.; Bingham, D.; Goh, J.; Boehly, T. R.; Sorce, A. T.

    2013-01-01

    We performed experiments at the Omega Laser Facility to characterize the initial, laser-driven state of a radiative shock experiment. These experiments aimed to measure the shock breakout time from a thin, laser-irradiated Be disk. The data are then used to inform a range of valid model parameters, such as electron flux limiter and polytropic γ, used when simulating radiative shock experiments using radiation hydrodynamics codes. The characterization experiment and the radiative shock experiment use a laser irradiance of ∼7 × 10 14 W cm −2 to launch a shock in the Be disk. A velocity interferometer and a streaked optical pyrometer were used to infer the amount of time for the shock to move through the Be disk. The experimental results were compared with simulation results from the Hyades code, which can be used to model the initial conditions of a radiative shock system using the CRASH code

  19. Exploratory laser-driven shock wave studies

    Solem, J.C.; Veeser, L.R.

    1977-11-01

    We show the results of a feasibility study for investigating shock structure and for measuring equation-of-state parameters using high-energy, short-pulse lasers. We discuss the temporal and spatial structure of the luminosity from laser-driven shock unloading in aluminum foils. We demonstrate that shock velocity can be measured by observing the time interval between shock emergence across two thicknesses and show data for shocks of 1.3 and 2.1 Mbar. The fact that we observe shock fronts cleanly breaking through steps as small as 3 μm indicates that the shock front thickness is very small in the few megabar region; this is the first experimental verification that these fronts are not more than a few micrometers thick. We present approximate measurements of free-surface velocity. Finally, we speculate on the use of these techniques to obtain detailed equation-of-state data

  20. Shock-induced chemistry in organic materials

    Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Steve [Los Alamos National Laboratory; Engelke, Ray [Los Alamos National Laboratory; Manner, Virginia [Los Alamos National Laboratory; Chellappa, Raja [Los Alamos National Laboratory; Yoo, Choong - Shik [WASHINGTON STATE UNIV

    2011-01-20

    The combined 'extreme' environments of high pressure, temperature, and strain rates, encountered under shock loading, offer enormous potential for the discovery of new paradigms in chemical reactivity not possible under more benign conditions. All organic materials are expected to react under these conditions, yet we currently understand very little about the first bond-breaking steps behind the shock front, such as in the shock initiation of explosives, or shock-induced reactivity of other relevant materials. Here, I will present recent experimental results of shock-induced chemistry in a variety of organic materials under sustained shock conditions. A comparison between the reactivity of different structures is given, and a perspective on the kinetics of reaction completion under shock drives.

  1. Experimental methods of shock wave research

    Seiler, Friedrich

    2016-01-01

    This comprehensive and carefully edited volume presents a variety of experimental methods used in Shock Waves research. In 14 self contained chapters this 9th volume of the “Shock Wave Science and Technology Reference Library” presents the experimental methods used in Shock Tubes, Shock Tunnels and Expansion Tubes facilities. Also described is their set-up and operation. The uses of an arc heated wind tunnel and a gun tunnel are also contained in this volume. Whenever possible, in addition to the technical description some typical scientific results obtained using such facilities are described. Additionally, this authoritative book includes techniques for measuring physical properties of blast waves and laser generated shock waves. Information about active shock wave laboratories at different locations around the world that are not described in the chapters herein is given in the Appendix, making this book useful for every researcher involved in shock/blast wave phenomena.

  2. Motion of shocks through interplanetary streams

    Burlaga, L.F.; Scudder, J.D.

    1975-01-01

    A model for the motion of flare-generated shocks through interplanetary streams is presented, illustrating the effects of a stream-shock interaction on the shock strength and geometry. It is a gas dynamic calculation based on Whitham's method and on an empirical approximation for the relevant characteristics of streams. The results show that the Mach number of a shock can decrease appreciably to near unity in the interaction region ahead of streams and that the interaction of a spherically symmetric shock with a spiral-shaped corotating stream can cause significant distortions of the initial shock front geometry. The geometry of the February 15--16, 1967, shock discussed by Lepping and Chao (1972) is qualitatively explained by this model

  3. Do oil shocks predict economic policy uncertainty?

    Rehman, Mobeen Ur

    2018-05-01

    Oil price fluctuations have influential role in global economic policies for developed as well as emerging countries. I investigate the role of international oil prices disintegrated into structural (i) oil supply shock, (ii) aggregate demand shock and (iii) oil market specific demand shocks, based on the work of Kilian (2009) using structural VAR framework on economic policies uncertainty of sampled markets. Economic policy uncertainty, due to its non-linear behavior is modeled in a regime switching framework with disintegrated structural oil shocks. Our results highlight that Indian, Spain and Japanese economic policy uncertainty responds to the global oil price shocks, however aggregate demand shocks fail to induce any change. Oil specific demand shocks are significant only for China and India in high volatility state.

  4. Shock Wave Dynamics in Weakly Ionized Plasmas

    Johnson, Joseph A., III

    1999-01-01

    An investigation of the dynamics of shock waves in weakly ionized argon plasmas has been performed using a pressure ruptured shock tube. The velocity of the shock is observed to increase when the shock traverses the plasma. The observed increases cannot be accounted for by thermal effects alone. Possible mechanisms that could explain the anomalous behavior include a vibrational/translational relaxation in the nonequilibrium plasma, electron diffusion across the shock front resulting from high electron mobility, and the propagation of ion-acoustic waves generated at the shock front. Using a turbulence model based on reduced kinetic theory, analysis of the observed results suggest a role for turbulence in anomalous shock dynamics in weakly ionized media and plasma-induced hypersonic drag reduction.

  5. Geomagnetic activity associated with Earth passage of interplanetary shock disturbances and coronal mass ejections

    Gosling, J.T.; McComas, D.J.; Phillips, J.L.; Bame, S.J.

    1991-01-01

    Previous work indicates that virtually all transient shock wave disturbances in the solar wind are driven by fast coronal mass ejection events (CMEs). Using a recently appreciated capability for distinguishing CMEs in solar wind data in the form of counterstreaming solar wind electron events, this paper explores the overall effectiveness of shock wave disturbances and CMEs in general in stimulating geomagnetic activity. The study is confined to the interval from mid-August 1978 through mid-October 1982, spanning the last solar activity maximum, when ISEE 3 was in orbit about the L1 Lagrange point 220 R e upstream from Earth. The authors find that all but one of the 37 largest geomagnetic storms in that era were associated with Earth passage of CMEs and/or shock disturbances, with the large majority of these storms being associated with interplanetary events where Earth encountered both a shock and the CME driving the shock (shock/CME events). Although CMEs and/or shock disturbances were increasingly the cause of geomagnetic activity as the level of geomagnetic activity increased, many smaller geomagnetic disturbances were unrelated to these events. Further, approximately half of all CMEs and half of all shock disturbances encountered by Earth did not produce any substantial geomagnetic activity as measured by the planetary geomagnetic index Kp. The geomagnetic effectiveness of Earth directed CMEs and shock wave disturbances was directly related to the flow speed, the magnetic field magnitude, and the strength of the southward (GSM) field component associated with the events. The initial speed of a CME close to the Sun appears to be the most crucial factor in determining if an earthward directed event will be effective in exciting a large geomagnetic disturbance

  6. Radial shock wave treatment alone is less efficient than radial shock wave treatment combined with tissue-specific plantar fascia-stretching in patients with chronic plantar heel pain.

    Rompe, Jan D; Furia, John; Cacchio, Angelo; Schmitz, Christoph; Maffulli, Nicola

    2015-12-01

    Whether shock wave therapy or shock wave therapy combined with plantar fascia-specific stretching is more efficient in treating chronic plantar heel pain remains unclear. The aim of the study was to test the null hypothesis of no difference of these two forms of management for patients who had unilateral plantar fasciopathy for a minimum duration of twelve months and which had failed at least three other forms of treatment. One hundred and fifty-two patients with chronic plantar fasciopathy were assigned to receive repetitive low-energy radial shock-wave therapy without local anesthesia, administered weekly for three weeks (Group 1, n = 73) or to receive the identical shock wave treatment and to perform an eight-week plantar fascia-specific stretching program (Group 2, n = 79). All patients completed the nine-item pain subscale of the validated Foot Function Index and a subject-relevant outcome questionnaire. Patients were evaluated at baseline, and at two, four, and twenty-four months after baseline. The primary outcome measures were a mean change in the Foot Function Index sum score at two months after baseline, a mean change in item 2 (pain during the first steps of walking in the morning) on this Index, and satisfaction with treatment. No difference in mean age, sex, weight or duration of symptoms was found between the groups at baseline. At two months after baseline, the Foot Function Index sum score showed significantly greater changes for the patients managed with shock-wave therapy plus plantar fascia-specific stretching than those managed with shock-wave therapy alone (p plantar fascia in combination with repetitive low-energy radial shock-wave therapy is more efficient than repetitive low-energy radial shock-wave therapy alone for the treatment of chronic symptoms of proximal plantar fasciopathy. Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.

  7. Implications of student mobility at the University of Granada: culture shock, education shock and “hosting shock”

    Inmaculada Soriano García

    2008-05-01

    Full Text Available The University of Granada heads the latest statistics in absolute figures in students’ mobility in Spain. Taking this assertion as a starting point, this paper shows the implications of culture shock for student mobility as well as the impact of student mobility for the different education levels and for host institutions. Furthermore, this paper presents the results obtained from the Temcu project (Teacher Training for the MulticulturalClassroom at the University, a European project based on the implications of the multicultural classroom at the University of Granada.

  8. Study on Reflected Shock Wave/Boundary Layer Interaction in a Shock Tube

    Kim, Dong Wook; Kim, Tae Ho; Kim, Heuy Dong [Andong Nat’l Univ., Andong (Korea, Republic of)

    2017-07-15

    The interaction between a shock wave and a boundary layer causes boundary layer separation, shock train, and in some cases, strong unsteadiness in the flow field. Such a situation is also observed in a shock tube, where the reflected shock wave interacts with the unsteady boundary layer. However, only a few studies have been conducted to investigate the shock train phenomenon in a shock tube. In the present study, numerical studies were conducted using the two-dimensional axisymmetric domain of a shock tube, and compressible Navier-Stokes equations were solved to clarify the flow characteristics of shock train phenomenon inside a shock tube. A detailed wave diagram was developed based on the present computational results, which were validated with existing experimental data.

  9. Insight into magnetorheological shock absorbers

    Gołdasz, Janusz

    2015-01-01

    This book deals with magnetorheological fluid theory, modeling and applications of automotive magnetorheological dampers. On the theoretical side a review of MR fluid compositions and key factors affecting the characteristics of these fluids is followed by a description of existing applications in the area of vibration isolation and flow-mode shock absorbers in particular. As a majority of existing magnetorheological devices operates in a so-called flow mode a critical review is carried out in that regard. Specifically, the authors highlight common configurations of flow-mode magnetorheological shock absorbers, or so-called MR dampers that have been considered by the automotive industry for controlled chassis applications. The authors focus on single-tube dampers utilizing a piston assembly with one coil or multiple coils and at least one annular flow channel in the piston.

  10. Magnetohydrodynamic shocks in molecular clouds

    Chernoff, D.F.

    1985-01-01

    Part one develops the mathematical and physical theory of one-dimensional, time-independent subalfvenic flow in partially ionized gas with magnetic fields, for application to shocks in molecular clouds. Unlike normal gas-dynamic shocks, the neutral flow may be continuous and cool if the gas radiates efficiently and does not self-ionize. Analytic solutions are given in the limit that the neutral gas is either adiabatic or isothermal (cold). Numerical techniques are developed and applied to find the neutral flow under general circumstances. Part two extends the theory and results of part one in three ways: (1) to faster, superalfvenic flow, (2) to complex gases containing heavy charged particles (grains) in addition to ions, containing heavy charged particles (grains) in addition to ions, electrons and neutrals, and (3) to the entire range in (Omega tau), the ratio of charged particle damping time to gyroperiod, expected in gas flows in molecular clouds

  11. MHD shocks in the ISM

    Chernoff, D. F.; Hollenbach, David J.; Mckee, Christopher F.

    1990-01-01

    Researchers survey shock solutions of a partially ionized gas with a magnetic field. The gas is modeled by interacting neutral, ion, electron and charged grain components. They employ a small neutral-ion chemical network to follow the dissociation and ionization of the major species. Cooling by molecular hydrogen (rotational, vibrational and dissociation), grains and dipole molecules is included. There are three basic types of solutions (C, C asterisk, and J) and some more complicated flows involving combinations of the basic types. The initial preshock conditions cover hydrogen nuclei densities of 1 less than n less than 10(exp 10) cm(-3) and shock velocities of 5 less than v(sub s) less than 60 km/s. The magnetic field is varied over 5 decades and the sensitivity of the results to grain parameters, UV and cosmic ray fluxes is ascertained. The parameter space is quite complicated, but there exist some simple divisions. When the initial ionization fraction is small (chi sub i less than 10(-5)), there is a sharp transition between fully C solutions at low velocity and strong J solutions at high velocity. When the initial ionization fraction is larger, C asterisk and/or very weak J shocks are present at low velocities in addition to the C solutions. The flow again changes to strong J shocks at high velocities. When the ionization fraction is large and the flow is only slightly greater than the bulk Alfven velocity, there is a complicated mixture of C, C asterisk and J solutions.

  12. Measuring resilience to energy shocks

    Molyneaux, Lynette; Brown, Colin; Foster, John; Wagner, Liam

    2015-01-01

    Measuring energy security or resilience in energy is, in the main, confined to indicators which are used for comparative purposes or to show trends rather than provide empirical evidence of resilience to unpredicted crises. In this paper, the electricity systems of the individual states within the United States of America are analysed for their response to the 1973-1982 and the 2003-2012 oil price shocks. Empirical evidence is sought for elements which are present in systems that experience r...

  13. Coronal mass ejection shock fronts containing the two types of intermediate shocks

    Steinolfson, R.S.; Hundhausen, A.J.

    1990-01-01

    Numerical solutions of the time-dependent, magnetohydrodynamic (MHD) equations in two dimensions are used to demonstrate the formation of both types of intermediate shocks in a single shock front for physical conditions that are an idealization of those expected to occur in some observed coronal mass ejections. The key to producing such a shock configuration in the simulations is the use of an initial atmosphere containing a magnetic field representative of that in a coronal streamer with open field lines overlying a region of closed field lines. Previous attempts using just open field lines (perpendicular to the surface) produced shock configurations containing just one of the two intermediate shock types. A schematic of such a shock front containing both intermediate shock types has been constructed previously based solely on the known properties of MHD shocks from the Rankine-Hugoniot equations and specific requirements placed on the shock solution at points along the front where the shock normal and upstream magnetic field are aligned. The shock front also contains, at various locations along the front, a hydrodynamic (nonmagnetic) shock, a switch-on shock, and a fast shock in addition to the intermediate shocks. This particular configuration occurs when the shock front speed exceeds the upstream (preshock) intermediate wave speed but is less than a critical speed defined in the paper (equation 1) along at least some portion of the shock front. A distinctive feature of the front is that it is concave upward (away from the surface) near the region where the field in the preshock plasma is normal to the front of near the central portion of the shock front

  14. Do oil price shocks matter? Evidence for some European countries

    Cunado, Juncal; Gracia, Fernando Perez de

    2003-01-01

    This paper analyzes the oil price-macro economy relationship by means of analyzing the impact of oil prices on inflation and industrial production indexes for many European countries using quarterly data for the period 1960-1999. First, we test for cointegration allowing for structural breaks among the variables. Second, and in order to account for the possible non-linear relationships, we use different transformation of oil price data. The main results suggest that oil prices have permanent effects on inflation and short run but asymmetric effects on production growth rates. Furthermore, significant differences are found among the responses of the countries to these shocks. (Author)

  15. Experimental investigation of shock wave - bubble interaction

    Alizadeh, Mohsen

    2010-04-09

    In this work, the dynamics of laser-generated single cavitation bubbles exposed to lithotripter shock waves has been investigated experimentally. The energy of the impinging shock wave is varied in several steps. High-speed photography and pressure field measurements simultaneously with image acquisition provide the possibility of capturing the fast bubble dynamics under the effect of the shock wave impact. The pressure measurement is performed using a fiber optic probe hydrophone (FOPH) which operates based on optical diagnostics of the shock wave propagating medium. After a short introduction in chapter 1 an overview of the previous studies in chapter 2 is presented. The reported literatures include theoretical and experimental investigations of several configurations of physical problems in the field of bubble dynamics. In chapter 3 a theoretical description of propagation of a shock wave in a liquid like water has been discussed. Different kinds of reflection of a shock wave at an interface are taken into account. Undisturbed bubble dynamics as well as interaction between a planar shock wave and an initially spherical bubble are explored theoretically. Some physical parameters which are important in this issue such as the velocity of the shock-induced liquid jet, Kelvin impulse and kinetic energy are explained. The shock waves are generated in a water filled container by a focusing piezoelectric generator. The shock wave profile has a positive part with pulse duration of ∼1 μs followed by a longer tension tail (i.e. ∼3 μs). In chapter 4 high-speed images depict the propagation of a shock wave in the water filled tank. The maximum pressure is also derived for different intensity levels of the shock wave generator. The measurement is performed in the free field (i.e. in the absence of laser-generated single bubbles). In chapter 5 the interaction between lithotripter shock waves and laserinduced single cavitation bubbles is investigated experimentally. An

  16. Shock ignition targets: gain and robustness vs ignition threshold factor

    Atzeni, Stefano; Antonelli, Luca; Schiavi, Angelo; Picone, Silvia; Volponi, Gian Marco; Marocchino, Alberto

    2017-10-01

    Shock ignition is a laser direct-drive inertial confinement fusion scheme, in which the stages of compression and hot spot formation are partly separated. The hot spot is created at the end of the implosion by a converging shock driven by a final ``spike'' of the laser pulse. Several shock-ignition target concepts have been proposed and relevant gain curves computed (see, e.g.). Here, we consider both pure-DT targets and more facility-relevant targets with plastic ablator. The investigation is conducted with 1D and 2D hydrodynamic simulations. We determine ignition threshold factors ITF's (and their dependence on laser pulse parameters) by means of 1D simulations. 2D simulations indicate that robustness to long-scale perturbations increases with ITF. Gain curves (gain vs laser energy), for different ITF's, are generated using 1D simulations. Work partially supported by Sapienza Project C26A15YTMA, Sapienza 2016 (n. 257584), Eurofusion Project AWP17-ENR-IFE-CEA-01.

  17. The effects of extracorporeal shock wave therapy on the pain and function of patients with degenerative knee arthritis.

    Lee, Ji-Hyun; Lee, Sangyong; Choi, SeokJoo; Choi, Yoon-Hee; Lee, Kwansub

    2017-03-01

    [Purpose] The purpose of this study was to identify the effects of extracorporeal shock wave therapy on the pain and function of patients with degenerative knee arthritis. [Subjects and Methods] Twenty patients with degenerative knee arthritis were divided into a conservative physical therapy group (n=10) and an extracorporeal shock wave therapy group (n=10). Both groups received general conservative physical therapy, and the extracorporeal shock wave therapy was additionally treated with extracorporeal shock wave therapy after receiving conservative physical therapy. Both groups were treated three times a week over a four-week period. The visual analogue scale was used to evaluate pain in the knee joints of the subjects, and the Korean Western Ontario and McMaster Universities Osteoarthritis Index was used to evaluate the function of the subjects. [Results] The comparison of the visual analogue scale and Korean Western Ontario and McMaster Universities Osteoarthritis Index scores within each group before and after the treatment showed statistically significant declines in scores in both the conservative physical therapy group and extracorporeal shock wave therapy group. A group comparison after the treatment showed statistically significant differences in these scores in the extracorporeal shock wave therapy group and the conservative physical therapy group. [Conclusion] extracorporeal shock wave therapy may be a useful nonsurgical intervention for reducing the pain of patients with degenerative knee arthritis and improving these patients' function.

  18. Particle Acceleration in Two Converging Shocks

    Wang, Xin; Wang, Na; Shan, Hao [Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi 830011 (China); Giacalone, Joe [Lunar and Planetary Laboratory, University of Arizona, Tucson AZ 85721 (United States); Yan, Yihua [CAS Key Laboratory of Solar Activity, National Astronomical Observatories, Beijing 100012 (China); Ding, Mingde, E-mail: wangxin@xao.ac.cn [Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education, Nanjing 210093 (China)

    2017-06-20

    Observations by spacecraft such as ACE , STEREO , and others show that there are proton spectral “breaks” with energy E {sub br} at 1–10 MeV in some large CME-driven shocks. Generally, a single shock with the diffusive acceleration mechanism would not predict the “broken” energy spectrum. The present paper focuses on two converging shocks to identify this energy spectral feature. In this case, the converging shocks comprise one forward CME-driven shock on 2006 December 13 and another backward Earth bow shock. We simulate the detailed particle acceleration processes in the region of the converging shocks using the Monte Carlo method. As a result, we not only obtain an extended energy spectrum with an energy “tail” up to a few 10 MeV higher than that in previous single shock model, but also we find an energy spectral “break” occurring on ∼5.5 MeV. The predicted energy spectral shape is consistent with observations from multiple spacecraft. The spectral “break,” then, in this case is caused by the interaction between the CME shock and Earth’s bow shock, and otherwise would not be present if Earth were not in the path of the CME.

  19. Simulation of turbulent flows containing strong shocks

    Fryxell, Bruce; Menon, Suresh

    2008-01-01

    Simulation of turbulent flows with strong shocks is a computationally challenging problem. The requirements for a method to produce accurate results for turbulence are orthogonal to those needed to treat shocks properly. In order to prevent an unphysical rate of decay of turbulent structures, it is necessary to use a method with very low numerical dissipation. Because of this, central difference schemes are widely used. However, computing strong shocks with a central difference scheme can produce unphysical post-shock oscillations that corrupt the entire flow unless additional dissipation is added. This dissipation can be difficult to localize to the area near the shock and can lead to inaccurate treatment of the turbulence. Modern high-resolution shock-capturing methods usually use upwind algorithms to provide the dissipation necessary to stabilize shocks. However, this upwind dissipation can also lead to an unphysical rate of decay of the turbulence. This paper discusses a hybrid method for simulating turbulent flows with strong shocks that couples a high-order central difference scheme with a high-resolution shock-capturing method. The shock-capturing method is used only in the vicinity of discontinuities in the flow, whereas the central difference scheme is used in the remainder of the computational domain. Results of this new method will be shown for a variety of test problems. Preliminary results for a realistic application involving detonation in gas-particle flows will also be presented.

  20. Electron velocity distributions near collisionless shocks

    Feldman, W.C.

    1984-01-01

    Recent studies of the amount of electron heating and of the shapes of electron velocity distributions across shocks near the earth are reviewed. It is found that electron heating increases with increasing shock strength but is always less than the ion heating. The scale length of electron heating is also less than that for the ions. Electron velocity distributions show characteristic shapes which depend on the strength of the shocks. At the weaker shocks, electron heating is mostly perpendicular to the ambient magnetic field, bar B, and results in Gaussian-shaped velocity distributions at low-to-moderate energies. At the stronger shocks, parallel heating predominates resulting in flat-topped velocity distributions. A reasonable interpretation of these results indicates that at the weaker shocks electron heating is dominated by a tendency toward conservation of the magnetic moment. At the stronger fast-mode shocks, this heating is thought to be dominated by an acceleration parallel to bar B produced by the macroscopic shock electric field followed by beam driven plasma instabilities. Some contribution to the heating at the stronger shocks from conservation of the magnetic moment and cross-field current-driven instabilities cannot be ruled out. Although the heating at slow-mode shocks is also dominated by instabilities driven by magnetic field-aligned electron beams, their acceleration mechanism is not yet established

  1. State-of-the-art monitoring in treatment of dengue shock syndrome: a case series.

    Moulton, Steven L; Mulligan, Jane; Srikiatkhachorn, Anon; Kalayanarooj, Siripen; Grudic, Greg Z; Green, Sharone; Gibbons, Robert V; Muniz, Gary W; Hinojosa-Laborde, Carmen; Rothman, Alan L; Thomas, Stephen J; Convertino, Victor A

    2016-08-24

    Early recognition and treatment of circulatory volume loss is essential in the clinical management of dengue viral infection. We hypothesized that a novel computational algorithm, originally developed for noninvasive monitoring of blood loss in combat casualties, could: (1) indicate the central volume status of children with dengue during the early stages of "shock"; and (2) track fluid resuscitation status. Continuous noninvasive photoplethysmographic waveforms were collected over a 5-month period from three children of Thai ethnicity with clinical suspicion of dengue. Waveform data were processed by the algorithm to calculate each child's Compensatory Reserve Index, where 1 represents supine normovolemia and 0 represents the circulatory volume at which hemodynamic decompensation occurs. Values between 1 and 0 indicate the proportion of reserve remaining before hemodynamic decompensation. This case report describes a 7-year-old Thai boy, another 7-year-old Thai boy, and a 9-year-old Thai boy who exhibited signs and symptoms of dengue shock syndrome; all the children had secondary dengue virus infections, documented by serology and reverse transcriptase polymerase chain reaction. The three boys experienced substantial plasma leakage demonstrated by pleural effusion index >25, ascites, and >20 % hemoconcentration. They received fluid administered intravenously; one received a blood transfusion. All three boys showed a significantly low initial Compensatory Reserve Index (≥0.20), indicating a clinical diagnosis of "near shock". Following 5 days with fluid resuscitation treatment, their Compensatory Reserve Index increased towards "normovolemia" (that is, Compensatory Reserve Index >0.75). The results from these cases demonstrate a new variation in the diagnostic capability to manage patients with dengue shock syndrome. The findings shed new light on a method that can avoid possible adverse effects of shock by noninvasive measurement of a patient's compensatory

  2. Need for an Ecological Index

    Rohan Wickramasinghe

    2007-12-01

    Full Text Available The article was published in the Sri Lankan newspaper 'The Island' on the 30th November 2005 after the World Environmental Education Congress (WEEC held in Milan. Author hopes it could provide a base for a project for senior school children or more senior students to devise an Ecological Index and ‘If nothing else, it could help them in thinking out the issues involved!’ Author supposes that could be a form of environmental education.

  3. [Acute heart failure: acute cardiogenic pulmonary edema and cardiogenic shock].

    Sánchez Marteles, Marta; Urrutia, Agustín

    2014-03-01

    Acute cardiogenic pulmonary edema and cardiogenic shock are two of the main forms of presentation of acute heart failure. Both entities are serious, with high mortality, and require early diagnosis and prompt and aggressive management. Acute pulmonary edema is due to the passage of fluid through the alveolarcapillary membrane and is usually the result of an acute cardiac episode. Correct evaluation and clinical identification of the process is essential in the management of acute pulmonary edema. The initial aim of treatment is to ensure hemodynamic stability and to correct hypoxemia. Other measures that can be used are vasodilators such as nitroglycerin, loop diuretics and, in specific instances, opioids. Cardiogenic shock is characterized by sustained hypoperfusion, pulmonary wedge pressure > 18 mmHg and a cardiac index 30 mmHg) and absent or reduced diuresis (acute myocardial infarction. Treatment consists of general measures to reverse acidosis and hypoxemia, as well as the use of vasopressors and inotropic drugs. Early coronary revascularization has been demonstrated to improve survival in shock associated with ischaemic heart disease. Copyright © 2014 Elsevier España, S.L. All rights reserved.

  4. Recent results from experimental studies on laser-plasma coupling in a shock ignition relevant regime

    Koester, P.; Antonelli, L.; Atzeni, S.; Badziak, J.; Baffigi, F.; Batani, D.; Cecchetti, C.A.; Chodukowski, T.; Consoli, F.; Cristoforetti, G.; De Angelis, R.; Folpini, G.; Gizzi, L.A.; Kalinowska, Z.; Krouský, Eduard; Kuchařík, M.; Labate, L.; Levato, T.; Liška, R.; Malka, G.; Maheut, Y.; Marocchino, A.; Nicolai, P.; O´Dell, T.; Parys, P.; Pisarczyk, T.; Rączka, P.; Renner, Oldřich; Rhee, Y.-J.; Ribeyre, X.; Richetta, M.; Rosinski, M.; Ryc, L.; Skála, Jiří; Schiavi, A.; Schurtz, G.; Šmíd, Michal; Spindloe, C.; Ullschmied, Jiří; Wolowski, J.; Zaras, A.

    2013-01-01

    Roč. 55, č. 12 (2013), , "124045-1"-"124045-8" ISSN 0741-3335 R&D Projects: GA MŠk(CZ) LC528; GA MŠk LM2010014 EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE Institutional support: RVO:68378271 ; RVO:61389021 Keywords : laser-produced plasma s * inertial confinement fusion * shock ignition * X-ray imaging spectroscopy * ion diagnostics * interferometry * shock breakout chron Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.386, year: 2013

  5. Limiting Performance Analysis of Underwater Shock Isolation of a System with Biodynamic Response Using Genetic Algorithm

    Z. Zong

    2000-01-01

    Full Text Available Biodynamic response of shipboard crew to underwater shock is of a major concern to navies. An underwater shock can produce very high accelerations, resulting in severe human injuries aboard a battleship. Protection of human bodies from underwater shock is implemented by installing onboard isolators. In this paper, the optimal underwater shock isolation to protect human bodies is studied. A simple shock-structure-isolator-human interaction model is first constructed. The model incorporates the effect of fluid-structure interaction, biodynamic response of human body, isolator influence. Based on this model, the optimum shock isolation is then formulated. The performance index and restriction are defined. Thirdly, GA (genetic algorithm is employed to solve the formulated optimization problem. GA is a powerful evolutionary optimization scheme suitable for large-scale and multi-variable optimization problems that are otherwise hard to be solved by conventional methods. A brief introduction to GA is given in the paper. Finally, the method is applied to an example problem and the limiting performance characteristic is obtained.

  6. Evolution of elastic precursor and plastic shock wave in copper via molecular dynamics simulations

    Perriot, Romain; Zhakhovsky, Vasily V; Oleynik, Ivan I; Inogamov, Nail A

    2014-01-01

    Large-scale molecular dynamics (MD) simulations are performed to investigate shock propagation in single crystal copper. It is shown that the P-V plastic Hugoniot is unique regardless of the sample's orientation, its microstructure, or its length. However, the P-V pathway to the final state is not, and depends on many factors. Specifically, it is shown that the pressure in the elastic precursor (the Hugoniot elastic limit (HEL)) decreases as the shock wave propagates in a micron-sized sample. The attenuation of the HEL in sufficiently-long samples is the main source of disagreement between previous MD simulations and experiment: while single crystal experiments showed that the plastic shock speed is orientation-independent, the simulated plastic shock speed was observed to be orientation-dependent in relatively short single-crystal samples. Such orientation dependence gradually disappears for relatively long, micrometer-sized, samples for all three low-index crystallographic directions (100), (110), and (111), and the plastic shock velocities for all three directions approach the one measured in experiment. The MD simulations also demonstrate the existence of subsonic plastic shock waves generated by relatively weak supporting pressures.

  7. Particle acceleration at quasi-perpendicular shock waves: Theory and observations at 1 AU

    Parker, L. Neergaard; Zank, G. P.; Hu, Q.

    2014-01-01

    The injection of particles into the diffusive shock acceleration mechanism at highly perpendicular (where θ Bn > 70°) interplanetary shocks is investigated. This extends the previous study of Neergaard Parker and Zank which focused on the injection problem at quasi-parallel interplanetary shocks. We use observations at 1 AU to construct upstream Maxwellian and κ-distributions that are then diffusively accelerated by the shock, thus yielding the downstream accelerated particle distribution. We compare the theoretical accelerated particle distribution to observations at 1 AU using Advanced Composition Explorer data. We classify our results for quasi-perpendicular shocks into three subcategories: those with ratios of the theoretical spectral index to observed power law of >1, ∼ 1, and <1, and compare the magnetic power spectral density plots of these categories. We find that in general the assumed upstream particle distribution that best fits the energetic particle observations is best represented by a κ-distribution, with κ = 4. The magnetic field fluctuations were representative of quasi-perpendicular shocks and showed no particular bias toward our spectral ratio subcategories. The subcategory with spectral ratio <0.9 yielded the largest injection energies for all groups. In all but two of the cases in this study, there were enough particles in the solar wind thermal core to account for the accelerated distribution, thereby giving a lower limit to the required injection energy needed to diffusively accelerate particles at a quasi-perpendicular interplanetary shock. In the remaining two cases, an additional population of particles was required to match the appropriate amplitude of the spectral index. For these cases, we used a low energy (1-50 keV) v –5 spectrum advocated by Fisk and Gloeckler.

  8. Computer simulations of collisionless shock waves

    Leroy, M.M.

    1984-01-01

    A review of the contributions of particle computer simulations to the understanding of the physics of magnetic shock waves in collisionless plasmas is presented. The emphasis is on the relation between the computer simulation results, spacecraft observations of shocks in space, and related theories, rather than on technical aspects of the numerics. It is shown that much has been learned from the comparison of ISEE spacecraft observations of the terrestrial bow shock and particle computer simulations concerning the quasi-perpendicular, supercritical shock (ion scale structure, ion reflection mechanism and ultimate dissipation processes). Particle computer simulations have also had an appreciable prospective role in the investigation of the physics of quasi-parallel shocks, about which still little is known observationally. Moreover, these numerical techniques have helped to clarify the process of suprathermal ion rejection by the shock into the foreshock, and the subsequent evolution of the ions in the foreshock. 95 references

  9. Molecular dynamics simulation of laser shock phenomena

    Fukumoto, Ichirou [Japan Atomic Energy Research Inst., Kansai Research Establishment, Advanced Photon Research Center, Neyagawa, Osaka (Japan).

    2001-10-01

    Recently, ultrashort-pulse lasers with high peak power have been developed, and their application to materials processing is expected as a tool of precision microfabrication. When a high power laser irradiates, a shock wave propagates into the material and dislocations are generated. In this paper, laser shock phenomena of the metal were analyzed using the modified molecular dynamics method, which has been developed by Ohmura and Fukumoto. The main results obtained are summarized as follows: (1) The shock wave induced by the Gaussian beam irradiation propagates radially from the surface to the interior. (2) A lot of dislocations are generated at the solid-liquid interface by the propagation of a shock wave. (3) Some dislocations are moved instantaneously with the velocity of the longitudinal wave when the shock wave passes, and their velocity is not larger than the transverse velocity after the shock wave has passed. (author)

  10. Entropy Generation Across Earth's Bow Shock

    Parks, George K.; McCarthy, Michael; Fu, Suiyan; Lee E. s; Cao, Jinbin; Goldstein, Melvyn L.; Canu, Patrick; Dandouras, Iannis S.; Reme, Henri; Fazakerley, Andrew; hide

    2011-01-01

    Earth's bow shock is a transition layer that causes an irreversible change in the state of plasma that is stationary in time. Theories predict entropy increases across the bow shock but entropy has never been directly measured. Cluster and Double Star plasma experiments measure 3D plasma distributions upstream and downstream of the bow shock that allow calculation of Boltzmann's entropy function H and his famous H-theorem, dH/dt O. We present the first direct measurements of entropy density changes across Earth's bow shock. We will show that this entropy generation may be part of the processes that produce the non-thermal plasma distributions is consistent with a kinetic entropy flux model derived from the collisionless Boltzmann equation, giving strong support that solar wind's total entropy across the bow shock remains unchanged. As far as we know, our results are not explained by any existing shock models and should be of interests to theorists.

  11. Remote shock sensing and notification system

    Muralidharan, Govindarajan; Britton, Charles L.; Pearce, James; Jagadish, Usha; Sikka, Vinod K.

    2008-11-11

    A low-power shock sensing system includes at least one shock sensor physically coupled to a chemical storage tank to be monitored for impacts, and an RF transmitter which is in a low-power idle state in the absence of a triggering signal. The system includes interference circuitry including or activated by the shock sensor, wherein an output of the interface circuitry is coupled to an input of the RF transmitter. The interface circuitry triggers the RF transmitting with the triggering signal to transmit an alarm message to at least one remote location when the sensor senses a shock greater than a predetermined threshold. In one embodiment the shock sensor is a shock switch which provides an open and a closed state, the open state being a low power idle state.

  12. Indexing contamination surveys

    Brown, R.L.

    1998-01-01

    The responsibility for safely managing the Tank Farms at Hanford belongs to Lockheed Martin Hanford Corporation which is part of the six company Project Hanford Management Team led by Fluor Daniel Hanford, Inc.. These Tank Farm Facilities contain numerous outdoor contamination areas which are surveyed at a periodicity consistent with the potential radiological conditions, occupancy, and risk of changes in radiological conditions. This document describes the survey documentation and data tracking method devised to track the results of contamination surveys this process is referred to as indexing. The indexing process takes a representative data set as an indicator for the contamination status of the facility. The data are further manipulated into a single value that can be tracked and trended using standard statistical methodology. To report meaningful data, the routine contamination surveys must be performed in a manner that allows the survey method and the data collection process to be recreated. Three key criteria are necessary to accomplish this goal: Accurate maps, consistent documentation, and consistent consolidation of data meeting these criteria provides data of sufficient quality to be tracked. Tracking of survey data is accomplished by converting the individual survey results into a weighted value, corrected for the actual number of survey points. This information can be compared over time using standard statistical analysis to identify trends. At the Tank Farms, the need to track and trend the facility's radiological status presents unique challenges. Many of these Tank Farm facilities date back to the second world war. The Tank Farm Facilities are exposed to weather extremes, plant and animal intrusion, as well as all of the normal challenges associated with handling radiological waste streams. Routine radiological surveys did not provide a radiological status adequate for continuing comparisons

  13. Role of echocardiography in reducing shock reversal time in pediatric septic shock: a randomized controlled trial

    Ahmed A. EL‐Nawawy

    2018-01-01

    Conclusion: Serial echocardiography provided crucial data for early recognition of septic myocardial dysfunction and hypovolemia that was not apparent on clinical assessment, allowing a timely management and resulting in shock reversal time reduction among children with septic shock.

  14. The earth's foreshock, bow shock, and magnetosheath

    Onsager, T. G.; Thomsen, M. F.

    1991-01-01

    Studies directly pertaining to the earth's foreshock, bow shock, and magnetosheath are reviewed, and some comparisons are made with data on other planets. Topics considered in detail include the electron foreshock, the ion foreshock, the quasi-parallel shock, the quasi-perpendicular shock, and the magnetosheath. Information discussed spans a broad range of disciplines, from large-scale macroscopic plasma phenomena to small-scale microphysical interactions.

  15. The earth's foreshock, bow shock, and magnetosheath

    Onsager, T.G.; Thomsen, M.F.

    1991-01-01

    Studies directly pertaining to the earth's foreshock, bow shock, and magnetosheath are reviewed, and some comparisons are made with data on other planets. Topics considered in detail include the electron foreshock, the ion foreshock, the quasi-parallel shock, the quasi-perpendicular shock, and the magnetosheath. Information discussed spans a broad range of disciplines, from large-scale macroscopic plasma phenomena to small-scale microphysical interactions. 184 refs

  16. Nonequilibrium chemistry in shocked molecular clouds

    Iglesias, E.R.; Silk, J.

    1978-01-01

    The gas phase chemistry is studied behind a 10 km s -1 shock propagating into a dense molecular cloud. Our principal conclusions are that the concentrations of certain molecules (CO, NH 3 , HCN, N 2 ) are unperturbed by the shock; other molecules (H 2 CO, CN, HCO + ) are greatly decreased in abundance; and substantial amounts of H 2 O, HCO, and CH 4 are produced. Approximately 10 6 yr (independent of the density) must elapse after shock passage before chemical equilibrium is attained

  17. Reaction effects in diffusive shock acceleration

    Drury, L.Oc.

    1984-01-01

    The effects of the reaction of accelerated particles back on the shock wave in the diffusive-shock-acceleration model of cosmic-ray generation are investigated theoretically. Effects examined include changes in the shock structure, modifications of the input and output spectra, scattering effects, and possible instabilities in the small-scale structure. It is pointed out that the latter two effects are applicable to any spatially localized acceleration mechanism. 14 references

  18. PIV tracer behavior on propagating shock fronts

    Glazyrin, Fyodor N; Mursenkova, Irina V; Znamenskaya, Irina A

    2016-01-01

    The present work was aimed at the quantitative particle image velocimetry (PIV) measurement of a velocity field near the front of a propagating shock wave and the study of the dynamics of liquid tracers crossing the shock front. For this goal, a shock tube with a rectangular cross-section (48  ×  24 mm) was used. The flat shock wave with Mach numbers M  =  1.4–2.0 propagating inside the tube channel was studied as well as an expanding shock wave propagating outside the channel with M  =  1.2–1.8 at its main axis. The PIV imaging of the shock fronts was carried out with an aerosol of dioctyl sebacate (DEHS) as tracer particles. The pressures of the gas in front of the shock waves studied ranged from 0.013 Mpa to 0.1 MPa in the series of experiments. The processed PIV data, compared to the 1D normal shock theory, yielded consistent values of wake velocity immediately behind the plain shock wave. Special attention was paid to the blurring of the velocity jump on the shock front due to the inertial particle lag and peculiarities of the PIV technique. A numerical algorithm was developed for analysis and correction of the PIV data on the shock fronts, based on equations of particle-flow interaction. By application of this algorithm, the effective particle diameter of the DEHS aerosol tracers was estimated as 1.03  ±  0.12 μm. A number of different formulations for particle drag were tested with this algorithm, with varying success. The results show consistency with previously reported experimental data obtained for cases of stationary shock waves. (paper)

  19. ATLS Hypovolemic Shock Classification by Prediction of Blood Loss in Rats Using Regression Models.

    Choi, Soo Beom; Choi, Joon Yul; Park, Jee Soo; Kim, Deok Won

    2016-07-01

    In our previous study, our input data set consisted of 78 rats, the blood loss in percent as a dependent variable, and 11 independent variables (heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure, pulse pressure, respiration rate, temperature, perfusion index, lactate concentration, shock index, and new index (lactate concentration/perfusion)). The machine learning methods for multicategory classification were applied to a rat model in acute hemorrhage to predict the four Advanced Trauma Life Support (ATLS) hypovolemic shock classes for triage in our previous study. However, multicategory classification is much more difficult and complicated than binary classification. We introduce a simple approach for classifying ATLS hypovolaemic shock class by predicting blood loss in percent using support vector regression and multivariate linear regression (MLR). We also compared the performance of the classification models using absolute and relative vital signs. The accuracies of support vector regression and MLR models with relative values by predicting blood loss in percent were 88.5% and 84.6%, respectively. These were better than the best accuracy of 80.8% of the direct multicategory classification using the support vector machine one-versus-one model in our previous study for the same validation data set. Moreover, the simple MLR models with both absolute and relative values could provide possibility of the future clinical decision support system for ATLS classification. The perfusion index and new index were more appropriate with relative changes than absolute values.

  20. Investigation of Shock Diffusers at Mach Number 1.85. 1 - Projecting Single Shock Cones

    1947-06-17

    cylindrical simulated combustion chamber was used to vary the outlet area of the flow through the diffuser. The pitot -static rake, located as shown in the...and II. Proc. Roy. Soc. (London), ser. A, vol. 139, no 838, Feb. 1, 1933, pp. 278-311. 5. Wyatt, DeMarquis D., and Hunczak, Henry R.: An...Simulated combustion u chamber A 90° W •—Conical damper S Static-pressure orifice ps pitot -static ""rake’ NATIONAL ADVISORY

  1. Condensed matter at high shock pressures

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-01-01

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N 2 , CO, SiO 2 -aerogel, H 2 O, and C 6 H 6 . The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab

  2. Radio emission from coronal and interplanetary shocks

    Cane, H.V.

    1987-01-01

    Observational data on coronal and interplanetary (IP) type II burst events associated with shock-wave propagation are reviewed, with a focus on the past and potential future contributions of space-based observatories. The evidence presented by Cane (1983 and 1984) in support of the hypothesis that the coronal (metric) and IP (kilometric) bursts are due to different shocks is summarized, and the fast-drift kilometric events seen at the same time as metric type II bursts (and designated shock-accelerated or shock-associated events) are characterized. The need for further observations at 0.5-20 MHz is indicated. 20 references

  3. Advanced and Exploratory Shock Sensing Mechanisms.

    Nelsen, Nicholas H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kolb, James D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kulkarni, Akshay G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorscher, Zachary [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Habing, Clayton D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mathis, Allen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Beller, Zachary J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    Mechanical component response to shock environments must be predictable in order to ensure reliability and safety. Whether the shock input results from accidental drops during transportation to projectile impact scenarios, the system must irreversibly transition into a safe state that is incapable of triggering the component . With this critical need in mind, the 2017 Nuclear Weapons Summer Product Realization Institute (NW SPRINT) program objective sought the design of a passive shock failsafe with emphasis on additively manufactured (AM) components. Team Advanced and Exploratory (A&E) responded to the challenge by designing and delivering multiple passive shock sensing mech anisms that activate within a prescribed mechanical shock threshold. These AM failsafe designs were tuned and validated using analytical and computational techniques including the shock response spectrum (SRS) and finite element analysis (FEA). After rapid prototyping, the devices experienced physical shock tests conducted on Sandia drop tables to experimentally verify performance. Keywords: Additive manufacturing, dynamic system, failsafe, finite element analysis, mechanical shock, NW SPRINT, shock respon se spectrum

  4. Irreversible thermodynamics of overdriven shocks in solids

    Wallace, D.C.

    1981-01-01

    An isotropic solid capable of transporting heat and of undergoing dissipative plastic flow, is treated. The shock is assumed to be a steady wave, and any phase changes or macroscopic inhomogeneities which might be induced by the shock are neglected. Under these conditions it is established that for an overdriven shock, no solution is possible without heat transport, and when the heat transport is governed by the steady conduction equation, no solution is possible without plastic dissipation as well. Upper and lower bounds are established for the thermodynamic variables, namely the shear stress, temperature, entropy, plastic strain, and heat flux, as functions of compression through the shock

  5. The source of real and nominal exchange rate fluctuations in Thailand: Real shock or nominal shock

    Le Thanh, Binh

    2015-01-01

    This paper examines the source of exchange rate fluctuations in Thailand. We employed a structural vector auto-regression (SVAR) model with the long-run neutrality restriction of Blanchard and Quah (1989) to investigate the changes in real and nominal exchange rates from 1994 to 2015. In this paper, we assume that there are two types of shocks which related to exchange rate movements: real shocks and nominal shocks. The empirical analysis indicates that real shocks are the fundamental compon...

  6. Model for shock wave chaos.

    Kasimov, Aslan R; Faria, Luiz M; Rosales, Rodolfo R

    2013-03-08

    We propose the following model equation, u(t) + 1/2(u(2)-uu(s))x = f(x,u(s)) that predicts chaotic shock waves, similar to those in detonations in chemically reacting mixtures. The equation is given on the half line, xorder partial differential equation. The chaos arises in the equation thanks to an interplay between the nonlinearity of the inviscid Burgers equation and a novel forcing term that is nonlocal in nature and has deep physical roots in reactive Euler equations.

  7. Adaptive inertial shock-absorber

    Faraj, Rami; Holnicki-Szulc, Jan; Knap, Lech; Seńko, Jarosław

    2016-01-01

    This paper introduces and discusses a new concept of impact absorption by means of impact energy management and storage in dedicated rotating inertial discs. The effectiveness of the concept is demonstrated in a selected case-study involving spinning management, a recently developed novel impact-absorber. A specific control technique performed on this device is demonstrated to be the main source of significant improvement in the overall efficiency of impact damping process. The influence of various parameters on the performance of the shock-absorber is investigated. Design and manufacturing challenges and directions of further research are formulated. (paper)

  8. How indexes have changed

    Farrar, G.L.

    1993-01-01

    The accompanying table compares refinery construction and operating wages monthly for the years 1990 and 1991. The Nelson-Farrar refinery construction cost indexes are inflation indexes, while the operating indexes incorporate a productivity which shows improvement with experience and the increasing size of operations. The refinery construction wage indexes in the table show a steady advance over the 2-year period. Common labor indexes moved up faster than skilled indexes. Refinery operating wages showed a steady increase, while productivities averaged higher near the end of the period. Net result is that labor costs remained steady for the period

  9. MULTI-SPACECRAFT ANALYSIS OF ENERGETIC HEAVY ION AND INTERPLANETARY SHOCK PROPERTIES IN ENERGETIC STORM PARTICLE EVENTS NEAR 1 au

    Ebert, R. W.; Dayeh, M. A.; Desai, M. I. [Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238 (United States); Jian, L. K. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Li, G. [The Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35756 (United States); Mason, G. M., E-mail: rebert@swri.edu [Johns Hopkins University/Applied Physics Laboratory, Laurel, MD 20273 (United States)

    2016-11-10

    We examine the longitude distribution of and relationship between interplanetary (IP) shock properties and ∼0.1–20 MeV nucleon{sup -1} O and Fe ions during seven multi-spacecraft energetic storm particle (ESP) events at 1 au. These ESP events were observed at two spacecraft and were primarily associated with low Mach number, quasi-perpendicular shocks. Key observations include the following: (i) the Alfvén Mach number increased from east to west of the coronal mass ejection source longitude, while the shock speed, compression ratios, and obliquity showed no clear dependence; (ii) the O and Fe time intensity profiles and peak intensities varied significantly between longitudinally separated spacecraft observing the same event, the peak intensities being larger near the nose and smaller along the flank of the IP shock; (iii) the O and Fe peak intensities had weak to no correlations with the shock parameters; (iv) the Fe/O time profiles showed intra-event variations upstream of the shock that disappeared downstream of the shock, where values plateaued to those comparable to the mean Fe/O of solar cycle 23; (v) the O and Fe spectral index ranged from ∼1.0 to 3.4, the Fe spectra being softer in most events; and (vi) the observed spectral index was softer than the value predicted from the shock compression ratio in most events. We conclude that while the variations in IP shock properties may account for some variations in O and Fe properties within these multi-spacecraft events, detailed examination of the upstream seed population and IP turbulence, along with modeling, are required to fully characterize these observations.

  10. Browse Title Index

    Items 51 - 99 of 99 ... Vol 13, No 2 (2004), Macro policy reform, labour market, poverty and inequality in urban ... Vol 17, No 2 (2008), Responding To An Income Shock Through .... Vol 19, No 2 (2010), Urbanization and Fertility Rates in Ethiopia ...

  11. Browse Title Index

    Vol 86, No 11 (2009), Life threatening spinal shock and complete neurological recovery following minor spinal cord trauma in a patient with pre-existing cervical canal ... Vol 92, No 12 (2015), Lipidemia status among HIV positive adult male on HAART attending the HIV clinic at Kericho district hospital, Kericho, Abstract.

  12. Browse Title Index

    Items 51 - 98 of 98 ... Vol 4, No 2 (2016), Microcredit in Uganda: Fundamental Reform or Just another Neoliberal Policy? Abstract PDF. Paige Miller, Jacqueline Murray Brux, Clementia Murembe Neema. Vol 6, No 1 (2018), Monetary policy shocks and industrial output in Nigeria: a dynamic effect, Abstract PDF. Akanbi Michael ...

  13. Western Alaska ESI: INDEX (Index Polygons)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing the boundaries of all the hardcopy cartographic products produced as part of the Environmental Sensitivity Index...

  14. Master Veteran Index (MVI)

    Department of Veterans Affairs — As of June 28, 2010, the Master Veteran Index (MVI) database based on the enhanced Master Patient Index (MPI) is the authoritative identity service within the VA,...

  15. Human Use Index (Future)

    U.S. Environmental Protection Agency — Human land uses may have major impacts on ecosystems, affecting biodiversity, habitat, air and water quality. The human use index (also known as U-index) is the...

  16. Human Use Index

    U.S. Environmental Protection Agency — Human land uses may have major impacts on ecosystems, affecting biodiversity, habitat, air and water quality. The human use index (also known as U-index) is the...

  17. IndexCat

    U.S. Department of Health & Human Services — IndexCat provides access to the digitized version of the printed Index-Catalogue of the Library of the Surgeon General's Office; eTK for medieval Latin texts; and...

  18. Body Mass Index Table

    ... Families ( We Can! ) Health Professional Resources Body Mass Index Table 1 for BMI greater than 35, go ... Health Information Email Alerts Jobs and Careers Site Index About NHLBI National Institute of Health Department of ...

  19. Shock compression profiles in ceramics

    Grady, D.E.; Moody, R.L.

    1996-03-01

    An investigation of the shock compression properties of high-strength ceramics has been performed using controlled planar impact techniques. In a typical experimental configuration, a ceramic target disc is held stationary, and it is struck by plates of either a similar ceramic or by plates of a well-characterized metal. All tests were performed using either a single-stage propellant gun or a two-stage light-gas gun. Particle velocity histories were measured with laser velocity interferometry (VISAR) at the interface between the back of the target ceramic and a calibrated VISAR window material. Peak impact stresses achieved in these experiments range from about 3 to 70 GPa. Ceramics tested under shock impact loading include: Al{sub 2}O{sub 3}, AlN, B{sub 4}C, SiC, Si{sub 3}N{sub 4}, TiB{sub 2}, WC and ZrO{sub 2}. This report compiles the VISAR wave profiles and experimental impact parameters within a database-useful for response model development, computational model validation studies, and independent assessment of the physics of dynamic deformation on high-strength, brittle solids.

  20. Shock-resistant scintillation detector

    Novak, W.P.

    1979-01-01

    A unique scintillation detector unit is disclosed which employs a special light transfer and reflector means that encases and protects the scintillator crystal against high g forces. The light transfer means comprises a flexible silicon rubber optical material bonded between the crystal and the optical window and having an axial thickness sufficient to allow the scintillator to move axially inside the container under high g forces without destroying the bonds. The reflector means comprises a soft elastic silicone rubber sleeve having a multiplicity of closely arranged tapered protrusions radiating toward and engaging the periphery of the scintillator crystal to cushion shocks effectively and having a reflective material, such as aluminum oxide powder, in the spaces between the protrusions. The reflector means provides improved shock absorption because of the uniform support and cushioning action of the protrusions and also provides the detector with high efficiency. The silicon rubber composition is specially compounded to include a large amount of aluminum oxide which enables the rubber to function effectively as a light reflector

  1. Titan atmospheric composition by hypervelocity shock layer analysis

    Nelson, H.F.; Park, C.; Whiting, E.E.

    1989-01-01

    The Cassini Mission, a NASA/ESA cooperative project which includes a deployment of probe into the atmosphere of Titan, is described, with particular attention given to the shock radiometer experiment planned for the Titan probe for the analysis of Titan's atmosphere. Results from a shock layer analysis are presented, demonstrating that the mole fractions of the major species (N2, CH4, and, possibly Ar) in the Titan atmosphere can be successfully determined by the Titan-probe radiometer, by measuring the intensity of the CN(violet) radiation emitted in the shock layer during the high velocity portion of the probe entry between 200 and 400 km altitude. It is shown that the sensitivity of the CN(violet) radiation makes it possible to determine the mole fractions of N2, CH4, and Ar to about 0.015, 0.003, and 0.01, respectively, i.e., much better than the present uncertainties in the composition of Titan atmosphere. 29 refs

  2. Exposure to whole-body vibration and mechanical shock: a field study of quad bike use in agriculture.

    Milosavljevic, Stephan; McBride, David I; Bagheri, Nasser; Vasiljev, Radivoj M; Mani, Ramakrishnan; Carman, Allan B; Rehn, Borje

    2011-04-01

    The purpose of this study was to determine exposure to whole-body vibration (WBV) and mechanical shock in rural workers who use quad bikes and to explore how personal, physical, and workplace characteristics influence exposure. A seat pad mounted triaxial accelerometer and data logger recorded full workday vibration and shock data from 130 New Zealand rural workers. Personal, physical, and workplace characteristics were gathered using a modified version of the Whole Body Vibration Health Surveillance Questionnaire. WBVs and mechanical shocks were analysed in accordance with the International Standardization for Organization (ISO 2631-1 and ISO 2631-5) standards and are presented as vibration dose value (VDV) and mechanical shock (S(ed)) exposures. VDV(Z) consistently exceeded European Union (Guide to good practice on whole body vibration. Directive 2002/44/EC on minimum health and safety, European Commission Directorate General Employment, Social Affairs and Equal Opportunities. 2006) guideline exposure action thresholds with some workers exceeding exposure limit thresholds. Exposure to mechanical shock was also evident. Increasing age had the strongest (negative) association with vibration and shock exposure with body mass index (BMI) having a similar but weaker effect. Age, daily driving duration, dairy farming, and use of two rear shock absorbers created the strongest multivariate model explaining 33% of variance in VDV(Z). Only age and dairy farming combined to explain 17% of the variance for daily mechanical shock. Twelve-month prevalence for low back pain was highest at 57.7% and lowest for upper back pain (13.8%). Personal (age and BMI), physical (shock absorbers and velocity), and workplace characteristics (driving duration and dairy farming) suggest that a mix of engineered workplace and behavioural interventions is required to reduce this level of exposure to vibration and shock.

  3. The ''injection problem'' for quasiparallel shocks

    Zank, G. P.; Rice, W. K. M.; le Roux, J. A.; Cairns, I. H.; Webb, G. M.

    2001-01-01

    For a particle to be accelerated diffusively at a shock by the first-order Fermi acceleration mechanism, the particle must be sufficiently energetic that it can scatter across all the micro- and macrostructure of the shock, experiencing compression between the converging upstream and downstream states. This is the well-known ''injection problem.'' Here the interaction of ions with the ramp of a quasiparallel shock is investigated. Some ions incident on the shock experience specular reflection, caused either by the cross-shock electrostatic potential or by mirroring as the magnetic field is bent and compressed through the ramp. Scattering of reflected ions by self-generated and pre-existing turbulence in the region upstream of the shock then acts to trap backstreaming ions and return them to the ramp, where some experience further reflections. Such repeated reflections and scattering energize a subpopulation of ions up to energies sufficiently large that they can be diffusively shock accelerated. Two ion distributions are considered: pickup ions which are assumed to be described by a shell distribution, are thermal solar wind ions which may be described by a kappa distribution. Injection efficiencies are found analytically to be very high for pickup ions and much lower for thermal solar wind ions, suggesting that this injection mechanism, stochastic reflected ion or SRI acceleration, is a natural precursor for the acceleration of the anomalous cosmic ray component at a quasiparallel shock. While significantly less efficient, SRI acceleration is also viable for thermal solar wind ions described by a kappa distribution

  4. PRECURSORS TO INTERSTELLAR SHOCKS OF SOLAR ORIGIN

    Gurnett, D. A.; Kurth, W. S. [University of Iowa, Department of Physics and Astronomy, Iowa City, IA 52242 (United States); Stone, E. C.; Cummings, A. C. [California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Krimigis, S. M.; Decker, R. B. [Applied Physics Laboratory/JHU, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Ness, N. F. [Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064 (United States); Burlaga, L. F., E-mail: donald-gurnett@uiowa.edu [NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States)

    2015-08-20

    On or about 2012 August 25, the Voyager 1 spacecraft crossed the heliopause into the nearby interstellar plasma. In the nearly three years that the spacecraft has been in interstellar space, three notable particle and field disturbances have been observed, each apparently associated with a shock wave propagating outward from the Sun. Here, we present a detailed analysis of the third and most impressive of these disturbances, with brief comparisons to the two previous events, both of which have been previously reported. The shock responsible for the third event was first detected on 2014 February 17 by the onset of narrowband radio emissions from the approaching shock, followed on 2014 May 13 by the abrupt appearance of intense electron plasma oscillations generated by electrons streaming outward ahead of the shock. Finally, the shock arrived on 2014 August 25, as indicated by a jump in the magnetic field strength and the plasma density. Various disturbances in the intensity and anisotropy of galactic cosmic rays were also observed ahead of the shock, some of which are believed to be caused by the reflection and acceleration of cosmic rays by the magnetic field jump at the shock, and/or by interactions with upstream plasma waves. Comparisons to the two previous weaker events show somewhat similar precursor effects, although differing in certain details. Many of these effects are very similar to those observed in the region called the “foreshock” that occurs upstream of planetary bow shocks, only on a vastly larger spatial scale.

  5. Corporate Policies with Permanent and Transitory Shocks

    J-P. Decamps (Jean-Paul); S. Gryglewicz (Sebastian); E. Morellec (Erwan); S. Villeneuve (Stephane)

    2016-01-01

    textabstractWe model the financing, cash holdings, and hedging policies of a firm facing financing frictions and subject to permanent and transitory cash flow shocks. We show that permanent and transitory shocks generate distinct, sometimes opposite, effects on corporate policies and use the model

  6. Shock dynamics in layered periodic media

    Ketcheson, David I.; Leveque, Randall J.

    2012-01-01

    of shock waves in a one-dimensional periodic layered medium by a computational study of time-reversibility and entropy evolution. We find that periodic layered media tend to inhibit shock formation. For small initial conditions and large impedance variation

  7. Particle acceleration and shock wave structure

    DRURY, L.O'C.

    1989-01-01

    A significant determinant in the large-scale structure and evolution of strong collisionless shocks under astrophysical conditions is probably the acceleration of charged particles. The reaction of these particles on the dynamical structure of the shock wave is discussed both theoretically and in the light of recent numerical calculations. Astrophysical implications for the evolution of supernova remnants, are considered. (author). 15 refs

  8. Laser shock wave and its applications

    Yang, Chaojun; Zhang, Yongkang; Zhou, Jianzhong; Zhang, Fang; Feng, Aixin

    2007-12-01

    The technology of laser shock wave is used to not only surface modification but also metal forming. It can be divided into three parts: laser shock processing, laser shock forming (LSF) and laser peenforming(LPF). Laser shock processing as a surface treatment to metals can make engineering components have a residual compressive stress so that it obviously improves their fatigue strength and stress corrosion performances, while laser shock forming (LSF) is a novel technique that is used in plastic deformation of sheet metal recently and Laser peen forming (LPF) is another new sheet metal forming process presented in recent years. They all can be carried out by a high-power and repetition pulse Nd:Glass laser device made by Jiangsu University. Laser shock technology has characterized of ultrahigh pressure and high strain rate (10 6 - 10 7s -1). Now, for different materials, we are able to form different metals to contours and shapes and simultaneity leave their surfaces in crack-resistant compressive stress state. The results show that the technology of laser shock wave can strengthen surface property and prolong fatigue life and especially can deform metals to shapes that could not be adequately made using conventional methods. With the development of the technology of laser shock wave, the applied fields of laser will become greater and greater.

  9. Introduction to Shock Waves and Shock Wave Research

    Anderson, William Wyatt [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-02

    M-9 and a number of other organizations at LANL and elsewhere study materials in dynamic processes. Often, this is described as “shock wave research,” but in reality is broader than is implied by that term. Most of our work is focused on dynamic compression and associated phenomena, but you will find a wide variety of things we do that, while related, are not simple compression of materials, but involve a much richer variety of phenomena. This tutorial will introduce some of the underlying physics involved in this work, some of the more common types of phenomena we study, and common techniques. However, the list will not be exhaustive by any means.

  10. Shock-drift accelerated electrons and n-distribution

    Vandas, Marek; Karlický, Marian

    2016-01-01

    Roč. 591, July (2016), A127/1-A127/6 ISSN 0004-6361 R&D Projects: GA ČR(CZ) GA14-19376S; GA ČR GA15-17490S; GA ČR GAP209/12/0103 Grant - others:EC(XE) 295272; EC(XE) 606862 Program:FP7; FP7 Institutional support: RVO:67985815 Keywords : shock waves * acceleration of particles * Sun flares Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.378, year: 2014

  11. Experimental study of radiative shocks at PALS facility

    Stehlé, C.; Gonzalez, M.; Kozlová, Michaela; Rus, Bedřich; Mocek, Tomáš; Acef, O.; Colombier, J.P.; Lanz, T.; Champion, N.; Jakubczak, Krzysztof; Polan, Jiří; Barroso, P.; Baudin, D.; Audit, E.; Dostál, Jan; Stupka, Michal

    2010-01-01

    Roč. 28, č. 2 (2010), s. 253-261 ISSN 0263-0346 R&D Projects: GA MŠk(CZ) LC528 Institutional research plan: CEZ:AV0Z10100523 Keywords : laboratory astrophysics * hydrodynamics * laser plasmas * shocks * stellar formation Subject RIV: BH - Optics, Masers, Lasers Impact factor: 3.656, year: 2010 http://journals.cambridge.org/action/displayFulltext?type=6&fid=7807203&jid=LPB&volumeId=28&issueId=02&aid=7807202&fulltextType=RA&fileId=S02630346100

  12. The Radiation, Interplanetary Shocks, and Coronal Sources (RISCS) Toolset

    Zank, G. P.; Spann, James F.

    2014-01-01

    The goal of this project is to serve the needs of space system designers and operators by developing an interplanetary radiation environment model within 10 AU:Radiation, Interplanetary Shocks, and Coronal Sources (RISCS) toolset: (1) The RISCS toolset will provide specific reference environments for space system designers and nowcasting and forecasting capabilities for space system operators; (2) We envision the RISCS toolset providing the spatial and temporal radiation environment external to the Earth's (and other planets') magnetosphere, as well as possessing the modularity to integrate separate applications (apps) that can map to specific magnetosphere locations and/or perform the subsequent radiation transport and dosimetry for a specific target.

  13. Shock loading predictions from application of indicial theory to shock-turbulence interactions

    Keefe, Laurence R.; Nixon, David

    1991-01-01

    A sequence of steps that permits prediction of some of the characteristics of the pressure field beneath a fluctuating shock wave from knowledge of the oncoming turbulent boundary layer is presented. The theory first predicts the power spectrum and pdf of the position and velocity of the shock wave, which are then used to obtain the shock frequency distribution, and the pdf of the pressure field, as a function of position within the interaction region. To test the validity of the crucial assumption of linearity, the indicial response of a normal shock is calculated from numerical simulation. This indicial response, after being fit by a simple relaxation model, is used to predict the shock position and velocity spectra, along with the shock passage frequency distribution. The low frequency portion of the shock spectra, where most of the energy is concentrated, is satisfactorily predicted by this method.

  14. Conjoint utility analysis of technical maturity and project progress of construction project

    Ma Wei

    2016-01-01

    Full Text Available In this paper, taking construction project as the research object, the relationship between the project maturity index calculated by the construction project technical risks with different fine degree and the project progress index is studied, and the equilibrium relationship between the Party A’s utility curve and the Party B’s cost curve of using project maturity index and project progress index as the research variables is analyzed. The results show that, when the construction project technical risk division is more precise, the conjoint utility of the project's technical maturity index and the project progress is higher, and the project’s Party A and Party B two sides are closer to the optimal equilibrium. This shows that the construction project technical risk must be finely divided, and managed and controlled respectively, which will help to improve the conjoint utility of the project Party A and Party B two sides.

  15. Shock-induced devolatilization of calcite

    Boslough, M. B.; Ahrens, T. J.; Vizgirda, J.; Becker, R. H.; Epstein, S.

    1982-01-01

    Experimental measurements of the release adiabats by Vizgirda (1981) indicate that substantial vaporization takes place upon release from shock pressures of 37 GPa for calcite and 14 GPa for aragonite. The present investigation includes the first controlled partial vaporization experiments on calcite. The experiments were conducted to test the predictions of the release adiabat experiments. The quantities of the gaseous species produced from shocked calcite and their carbon and oxygen isotopic compositions were determined, and the shock-induced effect on the Mn(2+) electron spin resonance spectrum in the shock-recovered calcite was observed. On the basis of the obtained results, it is concluded that shock stresses at the 17-18 GPa level give rise to volatilization of 0.03-0.3 (mole) percent of calcite to CO2 and CO. The devolatilization of calcite occurs at low pressure at significantly lower entropy densities than predicted on the basis of thermodynamic continuum models.

  16. Shock waves in helium at low temperatures

    Liepmann, H.W.; Torczynski, J.R.

    1986-01-01

    Results are reported from studies of the properties of low temperature He-4 using shock waves as a probe. Ideal shock tube theory is used to show that sonic speeds of Mach 40 are attainable in He at 300 K. Viscosity reductions at lower temperatures minimize boundary layer effects at the side walls. A two-fluid model is described to account for the phase transition which He undergoes at temperatures below 2.2 K, after which the quantum fluid (He II) and the normal compressed superfluid (He I) coexist. Analytic models are provided for pressure-induced shocks in He I and temperature-induced shock waves (called second sound) which appear in He II. The vapor-fluid interface of He I is capable of reflecting second and gasdynamic sound shocks, which can therefore be used as probes for studying phase transitions between He I and He II. 17 references

  17. Analytical extension of curved shock theory

    Emanuel, G.

    2018-03-01

    Curved shock theory (CST) is limited to shock waves in a steady, two-dimensional or axisymmetric (2-Ax) flow of a perfect gas. A unique feature of CST is its use of intrinsic coordinates that result in an elegant and useful formulation for flow properties just downstream of a shock. For instance, the downstream effect of upstream vorticity, shock wave curvature, and the upstream pressure gradient along a streamline is established. There have been several attempts to extend CST, as mentioned in the text. Removal of the steady, 2-Ax, and perfect gas limitations, singly or in combination, requires an appropriate formulation of the shock wave's jump relations and the intrinsic coordinate Euler equations. Issues discussed include flow plane versus osculating plane, unsteady flow, vorticity, an imperfect gas, etc. The extension of CST utilizes concepts from differential geometry, such as the osculating plane, streamline torsion, and the Serret-Frenet equations.

  18. 28th International Symposium on Shock Waves

    2012-01-01

    The University of Manchester hosted the 28th International Symposium on Shock Waves between 17 and 22 July 2011. The International Symposium on Shock Waves first took place in 1957 in Boston and has since become an internationally acclaimed series of meetings for the wider Shock Wave Community. The ISSW28 focused on the following areas: Blast Waves, Chemically Reacting Flows, Dense Gases and Rarefied Flows, Detonation and Combustion, Diagnostics, Facilities, Flow Visualisation, Hypersonic Flow, Ignition, Impact and Compaction, Multiphase Flow, Nozzle Flow, Numerical Methods, Propulsion, Richtmyer-Meshkov, Shockwave Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shockwave Phenomena and Applications, as well as Medical and Biological Applications. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 28 and individuals interested in these fields.

  19. Barrier experiment: Shock initiation under complex loading

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-01-12

    The barrier experiments are a variant of the gap test; a detonation wave in a donor HE impacts a barrier and drives a shock wave into an acceptor HE. The question we ask is: What is the trade-off between the barrier material and threshold barrier thickness to prevent the acceptor from detonating. This can be viewed from the perspective of shock initiation of the acceptor subject to a complex pressure drive condition. Here we consider key factors which affect whether or not the acceptor undergoes a shock-to-detonation transition. These include the following: shock impedance matches for the donor detonation wave into the barrier and then the barrier shock into the acceptor, the pressure gradient behind the donor detonation wave, and the curvature of detonation front in the donor. Numerical simulations are used to illustrate how these factors affect the reaction in the acceptor.

  20. Plane shock loading on mono- and nano-crystalline silicon carbide

    Branicio, Paulo S.; Zhang, Jingyun; Rino, José P.; Nakano, Aiichiro; Kalia, Rajiv K.; Vashishta, Priya

    2018-03-01

    The understanding of the nanoscale mechanisms of shock damage and failure in SiC is essential for its application in effective and damage tolerant coatings. We use molecular-dynamics simulations to investigate the shock properties of 3C-SiC along low-index crystallographic directions and in nanocrystalline samples with 5 nm and 10 nm grain sizes. The predicted Hugoniot in the particle velocity range of 0.1 km/s-6.0 km/s agrees well with experimental data. The shock response transitions from elastic to plastic, predominantly deformation twinning, to structural transformation to the rock-salt phase. The predicted strengths from 12.3 to 30.9 GPa, at the Hugoniot elastic limit, are in excellent agreement with experimental data.

  1. Standing non-dissipative shocks in black hole accretion and winds

    Chakrabarti, S.K.

    1988-07-01

    We present all non-dissipative shock solutions for stationary, axially symmetric and rotating adiabatic flows of small transverse thickness in black hole potential. We show that for a given initial and final states of the flow, there can be as many as four formal shock locations in both the accretion and the winds. Only two (three) of these locations are acceptable for accretion onto black holes (neutron stars) and three of these locations are acceptable for winds. We prove that the shock strength and the temperature jump have a lower limit which does not depend upon the parameters of the flow or the force field in which the flow moves and is only a function of the adiabatic index of flow. (author). 14 refs, 12 figs

  2. Small-Scale Shock Testing of Propellants and Ingredients

    Dawley, S

    2004-01-01

    .... The use of small-scale gap testing to evaluate the shock sensitivity of individual propellant ingredients and propellant formulations is a valuable method for experimentally establishing shock...

  3. Surface instabilities in shock loaded granular media

    Kandan, K.; Khaderi, S. N.; Wadley, H. N. G.; Deshpande, V. S.

    2017-12-01

    The initiation and growth of instabilities in granular materials loaded by air shock waves are investigated via shock-tube experiments and numerical calculations. Three types of granular media, dry sand, water-saturated sand and a granular solid comprising PTFE spheres were experimentally investigated by air shock loading slugs of these materials in a transparent shock tube. Under all shock pressures considered here, the free-standing dry sand slugs remained stable while the shock loaded surface of the water-saturated sand slug became unstable resulting in mixing of the shocked air and the granular material. By contrast, the PTFE slugs were stable at low pressures but displayed instabilities similar to the water-saturated sand slugs at higher shock pressures. The distal surfaces of the slugs remained stable under all conditions considered here. Eulerian fluid/solid interaction calculations, with the granular material modelled as a Drucker-Prager solid, reproduced the onset of the instabilities as seen in the experiments to a high level of accuracy. These calculations showed that the shock pressures to initiate instabilities increased with increasing material friction and decreasing yield strain. Moreover, the high Atwood number for this problem implied that fluid/solid interaction effects were small, and the initiation of the instability is adequately captured by directly applying a pressure on the slug surface. Lagrangian calculations with the directly applied pressures demonstrated that the instability was caused by spatial pressure gradients created by initial surface perturbations. Surface instabilities are also shown to exist in shock loaded rear-supported granular slugs: these experiments and calculations are used to infer the velocity that free-standing slugs need to acquire to initiate instabilities on their front surfaces. The results presented here, while in an idealised one-dimensional setting, provide physical understanding of the conditions required to

  4. X-ray spectroscopic characterization of shock-ignition-relevant plasmas

    Šmíd, Michal; Antonelli, L.; Renner, Oldřich

    2013-01-01

    Roč. 53, č. 2 (2013), 233-236 ISSN 1210-2709 R&D Projects: GA ČR GAP205/10/0814 Institutional support: RVO:68378271 Keywords : hot electrons * shock ignition * laser-produced plasma * X-ray spectroscopy * Kα radiation Subject RIV: BL - Plasma and Gas Discharge Physics

  5. Attenuation of surface waves in porous media: Shock wave experiments and modelling

    Chao, G.E; Smeulders, D.M.J.; Dongen, van M.E.H.

    2005-01-01

    In this project we conduct experimental and numerical investigations on the attenuation mechanisms of surface waves in poroelastic materials. Viscous dissipation effects are modelled in the framework of Biot's theory. The experiments are performed using a shock tube technique. Quantitative agreement

  6. Money velocity in an endogenous growth business cycle with credit shocks

    Benk, S.; Gillman, M.; Kejak, Michal

    2008-01-01

    Roč. 40, č. 6 (2008), s. 1281-1293 ISSN 0022-2879 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:AV0Z70850503 Keywords : money velocity * business cycle * credit shocks Subject RIV: AH - Economics Impact factor: 1.422, year: 2008

  7. Money velocity in an endogenous growth business cycle with credit shocks

    Benk, S.; Gillman, M.; Kejak, Michal

    -, 2007/5 (2007), s. 1-17 ISSN 1585-5600 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:MSM0021620846 Keywords : money velocity * business cycle * credit shocks Subject RIV: AH - Economics http://www.mnb.hu/Root/Dokumentumtar/MNB/Kiadvanyok/mnbhu_mnbfuzetek/WP_2007_5.pdf

  8. NUMERICAL SIMULATION OF THE SVS 13 MICROJET AND BOW SHOCK BUBBLE

    Gardner, Carl L.; Jones, Jeremiah R.; Hodapp, Klaus W.

    2016-01-01

    Numerical simulations of the SVS 13 microjet and bow shock bubble are performed using the WENO method that reproduces the main features and dynamics of data from the Keck Telescope/OSIRIS velocity-resolved integral field spectrograph: an expanding, cooler bow shock bubble, with the bubble center moving at approximately 50 km s −1 with a radial expansion velocity of 11 km s −1 , surrounding the fast, hotter jet, which is propagating at 156 km s −1 . Contact and bow shock waves are visible in the simulations both from the initial short jet pulse that creates the nearly spherical bow shock bubble and from the fast microjet, while a terminal Mach disk shock is visible near the tip of the continuous microjet, which reduces the velocity of the jet gas down to the flow velocity of the contact discontinuity at the leading edge of the jet. At 21.1 years after the launch of the initial bubble pulse, the jet has caught up with and penetrated almost all the way across the bow shock bubble of the slower initial pulse. At times later than about 22 years, the jet has penetrated through the bubble and thereafter begins to subsume its spherical form. Emission maps from the simulations of the jet—traced by the emission of the shock-excited 1.644 μ m [Fe ii] line—and the bow shock bubble—traced in the lower excitation 2.122 μ m H 2 1–0 S(1) line—projected onto the plane of the sky are presented, and are in good agreement with the Keck observations.

  9. Numerical Simulation of the SVS 13 Microjet and Bow Shock Bubble

    Gardner, Carl L.; Jones, Jeremiah R.; Hodapp, Klaus W.

    2016-10-01

    Numerical simulations of the SVS 13 microjet and bow shock bubble are performed using the WENO method that reproduces the main features and dynamics of data from the Keck Telescope/OSIRIS velocity-resolved integral field spectrograph: an expanding, cooler bow shock bubble, with the bubble center moving at approximately 50 km s-1 with a radial expansion velocity of 11 km s-1, surrounding the fast, hotter jet, which is propagating at 156 km s-1. Contact and bow shock waves are visible in the simulations both from the initial short jet pulse that creates the nearly spherical bow shock bubble and from the fast microjet, while a terminal Mach disk shock is visible near the tip of the continuous microjet, which reduces the velocity of the jet gas down to the flow velocity of the contact discontinuity at the leading edge of the jet. At 21.1 years after the launch of the initial bubble pulse, the jet has caught up with and penetrated almost all the way across the bow shock bubble of the slower initial pulse. At times later than about 22 years, the jet has penetrated through the bubble and thereafter begins to subsume its spherical form. Emission maps from the simulations of the jet—traced by the emission of the shock-excited 1.644 μm [Fe II] line—and the bow shock bubble—traced in the lower excitation 2.122 μm H2 1-0 S(1) line—projected onto the plane of the sky are presented, and are in good agreement with the Keck observations.

  10. Role of oil price shocks on macroeconomic activities: An SVAR approach to the Malaysian economy and monetary responses

    Ali Ahmed, Huson Joher; Wadud, I.K.M. Mokhtarul

    2011-01-01

    This study examines the impact of oil price uncertainty on Malaysian macroeconomic activities and monetary responses. We use a structural VAR (SVAR) model based on monthly data over the period 1986−2009. The EGARCH model estimates show an important asymmetric effect of oil price shocks on the conditional oil price volatility. Dynamic impulse response functions obtained from the SVAR model show a prolonged dampening effect of oil price volatility shock on Malaysian industrial production. We also find that levels of Consumer Price Index (CPI) decline with a positive shock to oil price uncertainty. This is the result of negative demand shock due to the postponement of consumption of big ticket items by individuals, households and other sectors of the economy. We also found that the Malaysian central bank adopts an expansionary monetary policy in response to oil price uncertainty. Variance decomposition analysis reconfirms that volatility in the oil price is the second most important factor to explain the variance of industrial production after its own shocks. These results shed some light on how the central bank of Malaysia can use controlling mechanisms to stabilize aggregate output and price level. - Highlights: ► Conditional volatility of the oil price causes a significant decline in aggregate output. ► Price level falls significantly to one standard deviation shock to oil price uncertainty. ► Malaysian central bank adopts an expansionary monetary policy in response to oil price shocks.

  11. Precision Index in the Multivariate Context

    Šiman, Miroslav

    2014-01-01

    Roč. 43, č. 2 (2014), s. 377-387 ISSN 0361-0926 R&D Projects: GA MŠk(CZ) 1M06047 Institutional support: RVO:67985556 Keywords : data depth * multivariate quantile * process capability index * precision index * regression quantile Subject RIV: BA - General Mathematics Impact factor: 0.274, year: 2014 http://library.utia.cas.cz/separaty/2014/SI/siman-0425059.pdf

  12. Lung protein leakage in feline septic shock.

    Schützer, K M; Larsson, A; Risberg, B; Falk, A

    1993-06-01

    The aim of the present study was to explore lung microvascular leakage of protein and water in a feline model of septic shock, using a double isotope technique with external gamma camera detection and gravimetric lung water measurements. The experiments were performed on artificially ventilated cats. One group of cats (n = 8) was given an infusion of live Escherichia coli bacteria, and another group (n = 5) served as a control group receiving saline. Plasma transferrin was radiolabeled in vivo with indium-113m-chloride, and erythrocytes were labeled with technetium-99m. The distribution of these isotopes in the lungs was continuously measured with a gamma camera. A normalized slope index (NSI) was calculated, indicative of the transferrin accumulation corrected for changes in local blood volume that reflect protein leakage. In the septic group there was a protein leakage after bacterial infusion, with a NSI of 39 x 10(-4) +/- 5 x 10(-4) min-1 (mean +/- SEM), and the PaO2 diminished from 21 +/- 1 to 9.5 +/- 1 kPa. In control cats a slight protein leakage with a NSI of 9 +/- 10(-4) +/- 2 x 10(-4) min-1 was detected, probably caused by the operative procedure, but PaO2 did not change. Wet-to-dry-weight ratios of postmortem lungs were not significantly different between the groups. It was concluded that an intravenous infusion of live E. coli bacteria induces a lung capillary protein leakage without increased lung water and a concomitantly disturbed gas exchange.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Indexes and parameters of activity in solar-terrestrial physics

    Minasyants, G.S.; Minasyants, T.M.

    2005-01-01

    The daily variation of different indexes and parameters of the solar-terrestrial physics at the 23 cycle were considered to find the most important from them for the forecast of geomagnetic activity. The validity of application of the Wolf numbers in quality of the characteristic of solar activity at sunspots is confirmed. The best geo-effective parameter in the arrival of the interplanetary shock from coronal mass ejection to an orbit of the Earth. (author)

  14. Cardiogenic Shock and Lung Injury as a Complication of Defibrillation

    Hasan Serdar Kıhtır

    2017-12-01

    Full Text Available Local burns, embolism, and arrhythmia are the most common side effects observed after electrical shock treatments. However, systolic function may be rarely affected and pulmonary edema may develop. The cases of pulmonary edema after electrical shock treatments have been reported since 1960s and the proposed mechanism is the inadequacy of the left atrium cuff and ventricle. It was learned that a 7-year-old-girl without any known disease except vesicoureteral reflux had a ventricular fibrillation during general anesthesia induction and defibrillation at 2 joule/kg was attempted. It was also learned that the procedure was delayed and the patient was diagnosed with a long QT (QTc: 0.47 ms and had respiratory distress and circulatory disturbances after four hours. Pulmonary edema and heart failure was determined, and due to hipoxemia (SpO2 <88% not getting any better with non-invasive ventilation, the patient was intubated and followed with mechanical ventilation. A thermodilution catheter was inserted into the femoral artery and a low cardiac index (CI: 1.58 L/min/m2, elevated extravascular lung water index (EVLWI: 18 mL/kg and high pulmonary vascular permeability index (PVPI: 7.6 were determined. The patient was treated by mechanical ventilation and vasoactive/inotropic management and discharged at the fifth day of hospitalization without any sequela. Having high EVLWI with high PVPI suggest that the pulmonary edema mechanism may also be caused by alveolocapillary membrane damage, which is not accompanied by heart failure alone. This case is presented to show that it is the first child in the literature and that the results of transpulmonary thermodilution can also give information about lung function as well as cardiac function.

  15. Effects of Atwood number on shock focusing in shock-cylinder interaction

    Ou, Junfeng; Ding, Juchun; Luo, Xisheng; Zhai, Zhigang

    2018-02-01

    The evolution of shock-accelerated heavy-gas cylinder surrounded by the air with different Atwood numbers (A_t=0.28, 0.50, 0.63) is investigated, concentrating on shock focusing and jet formation. Experimentally, a soap film technique is used to generate an ideal two-dimensional discontinuous gas cylinder with a clear surface, which can guarantee the observation of shock wave movements inside the cylinder. Different Atwood numbers are realized by different mixing ratios of SF_6 and air inside the cylinder. A high-speed schlieren system is adopted to capture the shock motions and jet morphology. Numerical simulations are also performed to provide more information. The results indicate that an inward jet is formed for low Atwood numbers, while an outward jet is generated for high Atwood numbers. Different Atwood numbers will lead to the differences in the relative velocities between the incident shock and the refraction shock, which ultimately results in the differences in shock competition near the downstream pole. The morphology and feature of the jet are closely associated with the position and intensity of shock focusing. The pressure and vorticity contours indicate that the jet formation should be attributed to the pressure pulsation caused by shock focusing, and the jet development is ascribed to the vorticity induction. Finally, a time ratio proposed in the previous work for determining the shock-focusing type is verified by experiments.

  16. Shock Mechanism Analysis and Simulation of High-Power Hydraulic Shock Wave Simulator

    Xiaoqiu Xu

    2017-01-01

    Full Text Available The simulation of regular shock wave (e.g., half-sine can be achieved by the traditional rubber shock simulator, but the practical high-power shock wave characterized by steep prepeak and gentle postpeak is hard to be realized by the same. To tackle this disadvantage, a novel high-power hydraulic shock wave simulator based on the live firing muzzle shock principle was proposed in the current work. The influence of the typical shock characteristic parameters on the shock force wave was investigated via both theoretical deduction and software simulation. According to the obtained data compared with the results, in fact, it can be concluded that the developed hydraulic shock wave simulator can be applied to simulate the real condition of the shocking system. Further, the similarity evaluation of shock wave simulation was achieved based on the curvature distance, and the results stated that the simulation method was reasonable and the structural optimization based on software simulation is also beneficial to the increase of efficiency. Finally, the combination of theoretical analysis and simulation for the development of artillery recoil tester is a comprehensive approach in the design and structure optimization of the recoil system.

  17. A Prognostic Model for Development of Profound Shock among Children Presenting with Dengue Shock Syndrome.

    Phung Khanh Lam

    Full Text Available To identify risk factors and develop a prediction model for the development of profound and recurrent shock amongst children presenting with dengue shock syndrome (DSS.We analyzed data from a prospective cohort of children with DSS recruited at the Paediatric Intensive Care Unit of the Hospital for Tropical Disease in Ho Chi Minh City, Vietnam. The primary endpoint was "profound DSS", defined as ≥2 recurrent shock episodes (for subjects presenting in compensated shock, or ≥1 recurrent shock episodes (for subjects presenting initially with decompensated/hypotensive shock, and/or requirement for inotropic support. Recurrent shock was evaluated as a secondary endpoint. Risk factors were pre-defined clinical and laboratory variables collected at the time of presentation with shock. Prognostic model development was based on logistic regression and compared to several alternative approaches.The analysis population included 1207 children of whom 222 (18% progressed to "profound DSS" and 433 (36% had recurrent shock. Independent risk factors for both endpoints included younger age, earlier presentation, higher pulse rate, higher temperature, higher haematocrit and, for females, worse hemodynamic status at presentation. The final prognostic model for "profound DSS" showed acceptable discrimination (AUC=0.69 for internal validation and calibration and is presented as a simple score-chart.Several risk factors for development of profound or recurrent shock among children presenting with DSS were identified. The score-chart derived from the prognostic models should improve triage and management of children presenting with DSS in dengue-endemic areas.

  18. Heat shock proteins of higher plants

    Key, J.L.; Lin, C.Y.; Chen, Y.M.

    1981-01-01

    The pattern of protein synthesis changes rapidly and dramatically when the growth temperture of soybean seedling tissue is increased from 28 0 C (normal) to about 40 0 C (heat shock). The synthesis of normal proteins is greatly decreased and a new set of proteins, heat shock proteins, is induced. The heat shock proteins of soybean consist of 10 new bands on one-dimensional NaDodSO 4 gels; a more complex pattern is observed on two-dimensional gels. when the tissue is returned to 28 0 C after 4 hr at 40 0 C, there is progressive decline in the synthesis of heat shock proteins and reappearance of a normal pattern of synthesis by 3 or 4 hr. In vitro translation of poly(A) + RNAs isolated from tissued grown at 28 and 40 0 C shows that the heat shock proteins are translated from a ndw set of mRNAs induced at 40 0 C; furthermore, the abundant class mRNAs for many of the normal proteins persist even though they are translated weakly (or not at all) in vivo at 40 or 42.5 0 C. The heat shock response in soybean appears similar to the much-studied heat shock phenomenon in Drosophila

  19. Overview of shock waves in medicine

    Cleveland, Robin O.

    2003-10-01

    A brief overview of three applications of shock waves is presented. Shock wave lithotripsy (SWL) has been in clinical use for more than 20 years. In the United States it is used to treat more than 80% of kidney stone cases and has wide acceptance with patients because it is a noninvasive procedure. Despite SWLs enormous success there is no agreement on how shock waves comminute stones. There is also a general acceptance that shock waves lead to trauma to the soft tissue of the kidney. Yet there has been little forward progress in developing lithotripters which provide comminution with less side-effects, indeed the original machine is still considered the gold standard. The last decade has seen the advent of new shock wave devices for treating principally musculoskeletal indications, such as plantar fasciitis, tennis elbow, and bone fractures that do not heal. This is referred to as shock wave therapy (SWT). The mechanisms by which SWT works are even less well understood than SWL and the consequences of bioeffects have also not been studied in detail. Shock waves have also been shown to be effective at enhancing drug delivery into cells and assisting with gene transfection. [Work partially supported by NIH.

  20. Structure of Energetic Particle Mediated Shocks Revisited

    Mostafavi, P.; Zank, G. P.; Webb, G. M.

    2017-01-01

    The structure of collisionless shock waves is often modified by the presence of energetic particles that are not equilibrated with the thermal plasma (such as pickup ions [PUIs] and solar energetic particles [SEPs]). This is relevant to the inner and outer heliosphere and the Very Local Interstellar Medium (VLISM), where observations of shock waves (e.g., in the inner heliosphere) show that both the magnetic field and thermal gas pressure are less than the energetic particle component pressures. Voyager 2 observations revealed that the heliospheric termination shock (HTS) is very broad and mediated by energetic particles. PUIs and SEPs contribute both a collisionless heat flux and a higher-order viscosity. We show that the incorporation of both effects can completely determine the structure of collisionless shocks mediated by energetic ions. Since the reduced form of the PUI-mediated plasma model is structurally identical to the classical cosmic ray two-fluid model, we note that the presence of viscosity, at least formally, eliminates the need for a gas sub-shock in the classical two-fluid model, including in that regime where three are possible. By considering parameters upstream of the HTS, we show that the thermal gas remains relatively cold and the shock is mediated by PUIs. We determine the structure of the weak interstellar shock observed by Voyager 1 . We consider the inclusion of the thermal heat flux and viscosity to address the most general form of an energetic particle-thermal plasma two-fluid model.

  1. Impaired Fracture Healing after Hemorrhagic Shock

    Philipp Lichte

    2015-01-01

    Full Text Available Impaired fracture healing can occur in severely injured patients with hemorrhagic shock due to decreased soft tissue perfusion after trauma. We investigated the effects of fracture healing in a standardized pressure controlled hemorrhagic shock model in mice, to test the hypothesis that bleeding is relevant in the bone healing response. Male C57/BL6 mice were subjected to a closed femoral shaft fracture stabilized by intramedullary nailing. One group was additionally subjected to pressure controlled hemorrhagic shock (HS, mean arterial pressure (MAP of 35 mmHg for 90 minutes. Serum cytokines (IL-6, KC, MCP-1, and TNF-α were analyzed 6 hours after shock. Fracture healing was assessed 21 days after fracture. Hemorrhagic shock is associated with a significant increase in serum inflammatory cytokines in the early phase. Histologic analysis demonstrated a significantly decreased number of osteoclasts, a decrease in bone quality, and more cartilage islands after hemorrhagic shock. μCT analysis showed a trend towards decreased bone tissue mineral density in the HS group. Mechanical testing revealed no difference in tensile failure. Our results suggest a delay in fracture healing after hemorrhagic shock. This may be due to significantly diminished osteoclast recruitment. The exact mechanisms should be studied further, particularly during earlier stages of fracture healing.

  2. Structure of Energetic Particle Mediated Shocks Revisited

    Mostafavi, P.; Zank, G. P. [Department of Space Science, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Webb, G. M. [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

    2017-05-20

    The structure of collisionless shock waves is often modified by the presence of energetic particles that are not equilibrated with the thermal plasma (such as pickup ions [PUIs] and solar energetic particles [SEPs]). This is relevant to the inner and outer heliosphere and the Very Local Interstellar Medium (VLISM), where observations of shock waves (e.g., in the inner heliosphere) show that both the magnetic field and thermal gas pressure are less than the energetic particle component pressures. Voyager 2 observations revealed that the heliospheric termination shock (HTS) is very broad and mediated by energetic particles. PUIs and SEPs contribute both a collisionless heat flux and a higher-order viscosity. We show that the incorporation of both effects can completely determine the structure of collisionless shocks mediated by energetic ions. Since the reduced form of the PUI-mediated plasma model is structurally identical to the classical cosmic ray two-fluid model, we note that the presence of viscosity, at least formally, eliminates the need for a gas sub-shock in the classical two-fluid model, including in that regime where three are possible. By considering parameters upstream of the HTS, we show that the thermal gas remains relatively cold and the shock is mediated by PUIs. We determine the structure of the weak interstellar shock observed by Voyager 1 . We consider the inclusion of the thermal heat flux and viscosity to address the most general form of an energetic particle-thermal plasma two-fluid model.

  3. Shock propagation in a heterogeneous medium

    Elbaz, D.

    2011-01-01

    In the frame of the inertial confinement fusion in direct drive, the use of foams as ablator allows the reduction of hydrodynamic instabilities created on the target by the direct laser irradiation. The foam is made up of carbon (CH) fibers impregnated of cryogenic deuterium-tritium (DT). In the past, studies have been carried out considering this foam to be a homogeneous medium. Yet, the foam presents heterogeneous features. We study the effects of this heterogeneity on the shock velocity when the laser irradiates the target. Thanks to experimental and numerical studies, we show that the shock propagates faster in the heterogeneous medium than in the homogeneous one with the same averaged density. This velocity gap depends on the presence rate of the CH fibers in the foam, the density ratio, the adiabatic coefficient and the foam geometry. We model the foam by different ways, more and more complex. The shock velocity modification is due to the baroclinicity which, during the interaction between the shock front and the interface, creates a vorticity deposition, responsible for the shock acceleration. Accordingly, an interface, which is plane and perpendicular to the front shock, maximizes the vorticity deposition and increases the velocity gaps between heterogeneous and homogeneous media. We found a correlation between the kinetic energy behind the shock front and the velocities relative difference. We compared our results with two analytical models. However, the system is not closed, so we can't for the moment develop a predictive model. (author) [fr

  4. Energetics of the terrestrial bow shock

    Hamrin, Maria; Gunell, Herbert; Norqvist, Patrik

    2017-04-01

    The solar wind is the primary energy source for the magnetospheric energy budget. Energy can enter through the magnetopause both as kinetic energy (plasma entering via e.g. magnetic reconnection and impulsive penetration) and as electromagnetic energy (e.g. by the conversion of solar wind kinetic energy into electromagnetic energy in magnetopause generators). However, energy is extracted from the solar wind already at the bow shock, before it encounters the terrestrial magnetopause. At the bow shock the supersonic solar wind is slowed down and heated, and the region near the bow shock is known to host many complex processes, including the accelerating of particles and the generation of waves. The processes at and near the bow shock can be discussed in terms of energetics: In a generator (load) process kinetic energy is converted to (from) electromagnetic energy. Bow shock regions where the solar wind is decelerated correspond to generators, while regions where particles are energized (accelerated and heated) correspond to loads. Recently, it has been suggested that currents from the bow shock generator should flow across the magnetosheath and connect to the magnetospause current systems [Siebert and Siscoe, 2002; Lopez et al., 2011]. In this study we use data from the Magnetospheric MultiScale (MMS) mission to investigate the energetics of the bow shock and the current closure, and we compare with the MHD simulations of Lopez et al., 2011.

  5. Radiative shocks with electron thermal conduction

    Borkowski, Kazimierz.

    1988-01-01

    The authors studies the influence of electron thermal conduction on radiative shock structure for both one- and two-temperature plasmas. The dimensionless ratio of the conductive length to the cooling length determines whether or not conduction is important, and shock jump conditions with conduction are established for a collisionless shock front. He obtains approximate solutions with the assumptions that the ionization state of the gas is constant and the cooling rate is a function of temperature alone. In the absence of magnetic fields, these solutions indicate that conduction noticeably influences normal-abundance interstellar shocks with velocities 50-100 km s -1 and dramatically affects metal-dominated shocks over a wide range of shock velocities. Magnetic fields inhibit conduction, but the conductive energy flux and the corresponding decrease in the post-shock electron temperature may still be appreciable. He calculates detailed steady-state radiative shock models in gas composed entirely of oxygen, with the purpose of explaining observations of fast-moving knots in Cas A and other oxygen-rich supernova remnants (SNRs). The O III ion, whose forbidden emission usually dominates the observed spectra, is present over a wide range of shock velocities, from 100 to 170 kms -1 . All models with conduction have extensive warm photoionization zones, which provides better agreement with observed optical (O I) line strengths. However, the temperatures in these zones could be lowered by (Si II) 34.8 μm and (Ne II) 12.8 μm cooling if Si and Ne are present in appreciable abundance relative to O. Such low temperatures would be inconsistent with the observed (O I) emission in oxygen-rich SNRs

  6. DSMC Computations for Regions of Shock/Shock and Shock/Boundary Layer Interaction

    Moss, James N.

    2001-01-01

    This paper presents the results of a numerical study of hypersonic interacting flows at flow conditions that include those for which experiments have been conducted in the Calspan-University of Buffalo Research Center (CUBRC) Large Energy National Shock (LENS) tunnel and the ONERA R5Ch low-density wind tunnel. The computations are made with the direct simulation Monte Carlo (DSMC) method of Bird. The focus is on Mach 9.3 to 11.4 flows about flared axisymmetric configurations, both hollow cylinder flares and double cones. The results presented highlight the sensitivity of the calculations to grid resolution, provide results concerning the conditions for incipient separation, and provide information concerning the flow structure and surface results for the extent of separation, heating, pressure, and skin friction.

  7. Temperature measurements of shock-compressed deuterium

    Holmes, N.C.; Ross, M.; Nellis, W.J.

    1994-11-01

    The authors measured the temperatures of single and double-shocked D 2 and H 2 up to 85 GPa (0.85 Mbar) and 5,200 K. While single shock temperatures, at pressures to 23 GPa, agree well with previous models, the double shock temperatures are as much as 40% lower than predicted. This is believed to be caused by molecular dissociation, and a new model of the hydrogen EOS at extreme conditions has been developed which correctly predicts their observations. These data and model have important implications for programs which use condensed-phase hydrogen in implosion systems

  8. Recent oil price shock and Tunisian economy

    Jbir, Rafik; Zouari-Ghorbel, Sonia

    2009-01-01

    The objective of this paper is to study the oil prices-macroeconomy relationship by the analysis of the role of subsidy policy. The vector autoregression (VAR) method was employed to analyze the data over the period 1993 Q1 - 2007 Q3. The results of the model using both linear and non-linear specifications indicate that there is no direct impact of oil price shock on the economic activity. The shock of oil prices affects economic activity indirectly. The most significant channel by which the effects of the shock are transmitted is the government's spending. (author)

  9. Delayed Failure in a Shock Loaded Alumina

    Cooper, G. A.; Millett, J. C. F.; Bourne, N. K.; Dandekar, D. P.

    2006-01-01

    Manganin stress gauges have been used to measure the lateral stress in a shock-loaded alumina. In combination with known longitudinal stresses, these have been used to determine the shear strength of this material, behind the shock front. The two-step nature of the lateral stress traces shows a slow moving front behind the main shock, behind which shear strength undergoes a significant decrease. Results also show that this front decreases markedly in velocity as the HEL is crossed, suggesting that limited plasticity occurs during inelastic deformation. Finally, comparison of measured shear strengths with other aluminas shows a high degree of agreement

  10. Turbulent energy generated by accelerations and shocks

    Mikaelian, K.O.

    1986-01-01

    The turbulent energy generated at the interface between two fluids undergoing a constant acceleration or a shock is calculated. Assuming linear density profiles in the mixed region we find E/sub turbulent//E/sub directed/ = 2.3A 2 % (constant acceleration) and 9.3A 2 % (shock), where A is the Atwood number. Diffusion models predict somewhat less turbulent energy and a density profile with a tail extending into the lower density fluid. Eddy sizes are approximately 27% (constant acceleration) and 17% (shock) of the mixing depth into the heavier fluid. 6 refs., 3 figs

  11. Supplement: Commodity Index Report

    Commodity Futures Trading Commission — Shows index traders in selected agricultural markets. These traders are drawn from the noncommercial and commercial categories. The noncommercial category includes...

  12. Indexing mergers and acquisitions

    Gang, Jianhua; Guo, Jie (Michael); Hu, Nan; Li, Xi

    2017-01-01

    We measure the efficiency of mergers and acquisitions by putting forward an index (the ‘M&A Index’) based on stochastic frontier analysis. The M&A Index is calculated for each takeover deal and is standardized between 0 and 1. An acquisition with a higher index encompasses higher efficiency. We find that takeover bids with higher M&A Indices are more likely to succeed. Moreover, the M&A Index shows a strong and positive relation with the acquirers’ post-acquisition stock perfo...

  13. Influence of Test Section Geometry on the Blast Environment in an Explosively Driven Conical Shock Tube

    2018-03-30

    ARL-TR-8335•MAR 2018 US Army Research Laboratory Influence of Test Section Geometry on theBlast Environment in an Explosively DrivenConical Shock...ARL-TR-8335•MAR 2018 US Army Research Laboratory Influence of Test Section Geometry on theBlast Environment in an Explosively DrivenConical Shock...TITLE AND SUBTITLE    5a. CONTRACT NUMBER  5b. GRANT NUMBER  5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S)    5d.  PROJECT  NUMBER  5e. TASK NUMBER  5f

  14. Relationships among energy price shocks, stock market, and the macroeconomy: evidence from China.

    Cong, Rong-Gang; Shen, Shaochuan

    2013-01-01

    This paper investigates the interactive relationships among China energy price shocks, stock market, and the macroeconomy using multivariate vector autoregression. The results indicate that there is a long cointegration among them. A 1% rise in the energy price index can depress the stock market index by 0.54% and the industrial value-adding growth by 0.037%. Energy price shocks also cause inflation and have a 5-month lag effect on stock market, which may result in the stock market "underreacting." The energy price can explain stock market fluctuations better than the interest rate over a longer time period. Consequently, investors should pay greater attention to the long-term effect of energy on the stock market.

  15. The Effects of Oil Price Shocks on IIP and CPI in Emerging Countries

    Yukino Sakashita

    2016-09-01

    Full Text Available In this paper, we investigate the effects of oil price shocks on the production and price level in five emerging countries through comparison with the United States, using a two-block structural VAR model of the global crude oil market proposed by Kilian and Park (see International Economic, vol. 50, 2009, pp. 1267–1287. Our main finding is that the effect of oil price shocks on the index of the industrial production (IIP and consumer price index (CPI in emerging countries also depends on where the changes fundamentally come from (this is also the case for the United States. We also found that some emerging countries showed unique impulse response patterns, the shapes of which are different from those of the United States and there are differences in impulse response patterns among emerging countries.

  16. Underwater electrical wire explosion: Shock wave from melting being overtaken by shock wave from vaporization

    Li, Liuxia; Qian, Dun; Zou, Xiaobing; Wang, Xinxin

    2018-05-01

    The shock waves generated by an underwater electrical wire explosion were investigated. A microsecond time-scale pulsed current source was used to trigger the electrical explosion of copper wires with a length of 5 cm and a diameter of 200 μm. The energy-storage capacitor was charged to a relatively low energy so that the energy deposited onto the wire was not large enough to fully vaporize the whole wire. Two shock waves were recorded with a piezoelectric gauge that was located at a position of 100 mm from the exploding wire. The first and weak shock wave was confirmed to be the contribution from wire melting, while the second and stronger shock wave was the contribution from wire vaporization. The phenomenon whereby the first shock wave generated by melting being overtaken by the shock wave due to vaporization was observed.

  17. Multiple spacecraft observations of interplanetary shocks Four spacecraft determination of shock normals

    Russell, C. T.; Mellott, M. M.; Smith, E. J.; King, J. H.

    1983-01-01

    ISEE 1, 2, 3, IMP 8, and Prognoz 7 observations of interplanetary shocks in 1978 and 1979 provide five instances where a single shock is observed by four spacecraft. These observations are used to determine best-fit normals for these five shocks. In addition to providing well-documented shocks for future investigations these data allow the evaluation of the accuracy of several shock normal determination techniques. When the angle between upstream and downstream magnetic field is greater than 20 deg, magnetic coplanarity can be an accurate single spacecraft method. However, no technique based solely on the magnetic measurements at one or multiple sites was universally accurate. Thus, the use of overdetermined shock normal solutions, utilizing plasma measurements, separation vectors, and time delays together with magnetic constraints, is recommended whenever possible.

  18. Importance of post-shock streams and sheath region as drivers of intense magnetospheric storms and high-latitude activity

    K. E. J. Huttunen

    2004-04-01

    Full Text Available Magnetic disturbances in the Earth's magnetosphere can be very different depending on the type of solar wind driver. We have determined the solar wind causes for intense magnetic storms (DstDst index was more difficult to model for a sheath region or a post-shock stream driven storm than for a storm caused by a magnetic cloud.

  19. DOES FEAR (VIX INDEX INCITE VOLATILITY IN FOOD PRICES?

    Gökhan Çınar

    2017-04-01

    Full Text Available Globally, the volatility trend in food prices has continued to increase. Different data give the impression that this volatility may be caused by the international finance markets’ propagation effect. For this reason, the study focused on the VIX (fear index that is used to measure the movement in Standard & Poor’s 500 index. The main objective of the study is to analyze the degree of volatility between the VIX index and the wheat market. The research is comprised of monthly data obtained from year 2000 to 2015. The study employs the BEKK GARCH method. The findings show that the variance shocks in the fear index damage food prices. The results may be useful to policy makers in researching the causes of changes in the prices of food commodity and taking necessary measures.

  20. Volatility Transmission between Dow Jones Stock Index and Emerging Bond Index

    Amir Saadaoui

    2016-04-01

    Full Text Available In this paper, we use a bivariate GARCH model to estimate simultaneously of the mean and the conditional variance between the Dow Jones stock index and some emerging bond indices. We used the DCC-GARCH model to graphically demonstrate the peaks of the volatility transmission. We examined this transmission using daily returns between July, 30, 2009 and January, 18, 2011 extracted from Datastream. Our results demonstrate that there is a significant transmission of shocks and volatility between the Dow Jones stock index and bond indices of the emerging countries. The results also confirm the idea that the crisis was transmitted from the United States to the emerging countries due to foreign investment made in these countries.

  1. Reliability assessment of competing risks with generalized mixed shock models

    Rafiee, Koosha; Feng, Qianmei; Coit, David W.

    2017-01-01

    This paper investigates reliability modeling for systems subject to dependent competing risks considering the impact from a new generalized mixed shock model. Two dependent competing risks are soft failure due to a degradation process, and hard failure due to random shocks. The shock process contains fatal shocks that can cause hard failure instantaneously, and nonfatal shocks that impact the system in three different ways: 1) damaging the unit by immediately increasing the degradation level, 2) speeding up the deterioration by accelerating the degradation rate, and 3) weakening the unit strength by reducing the hard failure threshold. While the first impact from nonfatal shocks comes from each individual shock, the other two impacts are realized when the condition for a new generalized mixed shock model is satisfied. Unlike most existing mixed shock models that consider a combination of two shock patterns, our new generalized mixed shock model includes three classic shock patterns. According to the proposed generalized mixed shock model, the degradation rate and the hard failure threshold can simultaneously shift multiple times, whenever the condition for one of these three shock patterns is satisfied. An example using micro-electro-mechanical systems devices illustrates the effectiveness of the proposed approach with sensitivity analysis. - Highlights: • A rich reliability model for systems subject to dependent failures is proposed. • The degradation rate and the hard failure threshold can shift simultaneously. • The shift is triggered by a new generalized mixed shock model. • The shift can occur multiple times under the generalized mixed shock model.

  2. Impact of Dobutamine in Patients With Septic Shock: A Meta-Regression Analysis.

    Nadeem, Rashid; Sockanathan, Shivani; Singh, Mukesh; Hussain, Tamseela; Kent, Patrick; AbuAlreesh, Sarah

    2017-05-01

    Septic shock frequently requires vasopressor agents. Conflicting evidence exists for use of inotropes in patients with septic shock. Data from English studies on human adult septic shock patients were collected. A total of 83 studies were reviewed, while 11 studies with 21 data sets including 239 patients were pooled for meta-regression analysis. For VO2, pooled difference in means (PDM) was 0.274. For cardiac index (CI), PDM was 0.783. For delivery of oxygen, PDM was -0.890. For heart rate, PDM was -0.714. For left ventricle stroke work index, PDM was 0.375. For mean arterial pressure, PDM was -0.204. For mean pulmonary artery pressure, PDM was 0.085. For O2 extraction, PDM was 0.647. For PaCO2, PDM was -0.053. For PaO2, PDM was 0.282. For pulmonary artery occlusive pressure, PDM was 0.270. For pulmonary capillary wedge pressure, PDM was 0.300. For PVO2, PDM was -0.492. For right atrial pressure, PDM was 0.246. For SaO2, PDM was 0.604. For stroke volume index, PDM was 0.446. For SvO2, PDM was -0.816. For systemic vascular resistance, PDM was -0.600. For systemic vascular resistance index, PDM was 0.319. Meta-regression analysis was performed for VO2, DO2, CI, and O2 extraction. Age was found to be significant confounding factor for CI, DO2, and O2 extraction. APACHE score was not found to be a significant confounding factor for any of the parameters. Dobutamine seems to have a positive effect on cardiovascular parameters in patients with septic shock. Prospective studies with larger samples are required to further validate this observation.

  3. Shock wave physics group (M-6)

    Morris, C.E.

    1981-01-01

    Experimental facilities and activities of the shock wave physics group at LASL are described. The facilities include a compressed gas gun, two-stage gas gun, high explosive facilities, and a pulsed megagauss field facility

  4. Integrated microelectromechanical gyroscope under shock loads

    Nesterenko, T. G.; Koleda, A. N.; Barbin, E. S.

    2018-01-01

    The paper presents a new design of a shock-proof two-axis microelectromechanical gyroscope. Without stoppers, the shock load enables the interaction between the silicon sensor elements. Stoppers were installed in the gyroscope to prevent the contact interaction between electrodes and spring elements with fixed part of the sensor. The contact of stoppers occurs along the plane, thereby preventing the system from serious contact stresses. The shock resistance of the gyroscope is improved by the increase in its eigenfrequency at which the contact interaction does not occur. It is shown that the shock load directed along one axis does not virtually cause the movement of sensing elements along the crosswise axes. Maximum stresses observed in the proposed gyroscope at any loading direction do not exceed the value allowable for silicon.

  5. Tribology Aspect of Rubber Shock Absorbers Development

    M. Banić

    2013-09-01

    Full Text Available Rubber is a very flexible material with many desirable properties Which enable its broad use in engineering practice. Rubber or rubber-metal springs are widely used as anti-vibration or anti-shock components in technical systems. Rubber-metal springs are usually realized as a bonded assembly, however especially in shock absorbers, it is possible to realize free contacts between rubber and metal parts. In previous research it authors was observed that friction between rubber and metal in such case have a significant influence on the damping characteristics of shock absorber. This paper analyzes the development process of rubber or rubber-metal shock absorbers realized free contacts between the constitutive parts, starting from the design, construction, testing and operation, with special emphasis on the development of rubber-metal springs for the buffing and draw gear of railway vehicles.

  6. Role of drifts in diffusive shock acceleration

    Decker, R.B.

    1988-01-01

    The role played by shock-associated drifts during the diffusive acceleration of charged particles at collisionless MHD shocks is evaluated. In the rest frame of the shock, the total energy gained by a particle is shown to result from two coupled acceleration mechanisms, the usual first-order Fermi mechanism and the drift mechanism. When averaged over a distribution of particles, the ratio of the drift-associated energy gain to the total energy is found to be independent of the total energy at a given theta1 (the angle between the shock normal and the unperturbed upstream magnetic field) in agreement with theoretical predictions. No evidence is found for drift-associated deceleration, suggesting that drifts always augment acceleration. 35 references

  7. Shock Thermodynamic Applied Research Facility (STAR)

    Federal Laboratory Consortium — The STAR facility, within Sandia's Solid Dynamic Physics Department, is one of a few institutions in the world with a major shock-physics program. This is the only...

  8. Nonequilibrium recombination after a curved shock wave

    Wen, Chihyung; Hornung, Hans

    2010-02-01

    The effect of nonequilibrium recombination after a curved two-dimensional shock wave in a hypervelocity dissociating flow of an inviscid Lighthill-Freeman gas is considered. An analytical solution is obtained with the effective shock values derived by Hornung (1976) [5] and the assumption that the flow is ‘quasi-frozen’ after a thin dissociating layer near the shock. The solution gives the expression of dissociation fraction as a function of temperature on a streamline. A rule of thumb can then be provided to check the validity of binary scaling for experimental conditions and a tool to determine the limiting streamline that delineates the validity zone of binary scaling. The effects on the nonequilibrium chemical reaction of the large difference in free stream temperature between free-piston shock tunnel and equivalent flight conditions are discussed. Numerical examples are presented and the results are compared with solutions obtained with two-dimensional Euler equations using the code of Candler (1988) [10].

  9. Critical point anomalies include expansion shock waves

    Nannan, N. R., E-mail: ryan.nannan@uvs.edu [Mechanical Engineering Discipline, Anton de Kom University of Suriname, Leysweg 86, PO Box 9212, Paramaribo, Suriname and Process and Energy Department, Delft University of Technology, Leeghwaterstraat 44, 2628 CA Delft (Netherlands); Guardone, A., E-mail: alberto.guardone@polimi.it [Department of Aerospace Science and Technology, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy); Colonna, P., E-mail: p.colonna@tudelft.nl [Propulsion and Power, Delft University of Technology, Kluyverweg 1, 2629 HS Delft (Netherlands)

    2014-02-15

    From first-principle fluid dynamics, complemented by a rigorous state equation accounting for critical anomalies, we discovered that expansion shock waves may occur in the vicinity of the liquid-vapor critical point in the two-phase region. Due to universality of near-critical thermodynamics, the result is valid for any common pure fluid in which molecular interactions are only short-range, namely, for so-called 3-dimensional Ising-like systems, and under the assumption of thermodynamic equilibrium. In addition to rarefaction shock waves, diverse non-classical effects are admissible, including composite compressive shock-fan-shock waves, due to the change of sign of the fundamental derivative of gasdynamics.

  10. Shock Wave Science and Technology Reference Library

    2007-01-01

    Shock waves in multiphase flows refers to a rich variety of phenomena of interest to physicists, chemists, and fluid dynamicists, as well as mechanical, biomedical and aeronautical engineers. This volume treats shock and expansion waves in (bullet) complex, bubbly liquids (L van Wijngaarden, Y Tomita, V Kedrinskii) and (bullet) cryogenic liquids (M Murakami) and examines the relationship of shock waves with (bullet) phase transitions (A Guha, CF Delale, G Schnerr, MEH van Dongen) (bullet) induced phase transitions (GEA Meier) as well as their interaction with (bullet) solid foams, textiles, porous and granular media (B Skews, DMJ Smeulders, MEH van Dongen, V Golub, O Mirova) All chapters are self-contained, so they can be read independently, although they are of course thematically interrelated. Taken together, they offer a timely reference on shock waves in multiphase flows, including new viewpoints and burgeoning developments. The book will appeal to beginners as well as professional scientists and engineer...

  11. Comments on ''Analysis of spherical imploding shocks''

    Lazarus, R.B.

    1980-01-01

    It is asserted that Fujimoto and Mishkin's article is incorrect in its claim for a pressure extremum at or behind the shock for all values of γ and in its claim for an analytical form for the similarity exponent

  12. Shock-induced modification of inorganic powders

    Graham, R.A.; Morosin, B.; Venturini, E.L.; Beauchamp, E.K.; Hammetter, W.F.

    1984-01-01

    The results of studies performed to quantify the characteristics of TiO2, ZrO2 and Si3N4 powders exposed to explosive loading and post-shock analysis are reported. The shocks were produced with plane wave generators and explosive pads impinging on steel disks, a copper recovery fixture, and then the samples. Peak pressures of 13 and 17 GPa were attained, along with 40 GPz at the center of the powder cavity. Data are provided on the changes occurring during the explosive densification and X-ray and paramagnetic studies of the products. Only fractured disks were obtained in the trials. The shock-treated materials were more free flowing than the original powders, which were fluffy. Post-shock annealing was a significant feature of the treated powders

  13. SPECIAL PURPOSE SHOCK TUBE for BLAST ASSESSMENT

    Federal Laboratory Consortium — This device is a specially designed shock tube for testing fabric samples in a controlled environment. The device determines the appropriate types of sensors to be...

  14. Collisions on relativistic nuclei: shock waves

    Gudima, K.K.; Toneev, V.D.

    1976-01-01

    Experiments are analysed which indicate the possible generation of shock waves in collisions of two nuclei. Another interpretation of these data is proposed and the concerned new experiments are discussed

  15. Analysis of Z Pinch Shock Wave Experiments

    Asay, James; Budge, Kent G.; Chandler, Gordon; Fleming, Kevin; Hall, Clint; Holland, Kathleen; Konrad, Carl; Lawrence, Jeffery; Trott, Wayne; Trucano, Timothy

    1999-01-01

    In this paper, we report details of our computational study of two shock wave physics experiments performed on the Sandia Z machine in 1998. The novelty of these particular experiments is that they represent the first successful application of VISAR interferometry to diagnose shock waves generated in experimental payloads by the primary X-ray pulse of the machine. We use the Sandia shock-wave physics code ALEGRA to perform the simulations reported in this study. Our simulations are found to be in fair agreement with the time-resolved VISAR experimental data. However, there are also interesting and important discrepancies. We speculate as to future use of time-resolved shock wave data to diagnose details of the Z machine X-ray pulse in the future

  16. Shock Tube Measurements for Liquid Fuels Combustion

    Hanson, Ronald K

    2006-01-01

    ...) fundamental studies of fuel spray evaporation rates and ignition times of low-vapor pressure fuels such as JP-8, diesel fuel and normal alkane surrogates in a new aerosol shock tube using state...

  17. Condensed matter at high shock pressures

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-07-12

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N/sub 2/, CO, SiO/sub 2/-aerogel, H/sub 2/O, and C/sub 6/H/sub 6/. The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab.

  18. Shock wave science and technology reference library

    2009-01-01

    This book, as a volume of the Shock Wave Science and Technology Reference Library, is primarily concerned with detonation waves or compression shock waves in reactive heterogeneous media, including mixtures of solid, liquid and gas phases. The topics involve a variety of energy release and control processes in such media - a contemporary research field that has found wide applications in propulsion and power, hazard prevention as well as military engineering. The six extensive chapters contained in this volume are: - Spray Detonation (SB Murray and PA Thibault) - Detonation of Gas-Particle Flow (F Zhang) - Slurry Detonation (DL Frost and F Zhang) - Detonation of Metalized Composite Explosives (MF Gogulya and MA Brazhnikov) - Shock-Induced Solid-Solid Reactions and Detonations (YA Gordopolov, SS Batsanov, and VS Trofimov) - Shock Ignition of Particles (SM Frolov and AV Fedorov) Each chapter is self-contained and can be read independently of the others, though, they are thematically interrelated. They offer a t...

  19. Medical and biomedical applications of shock waves

    Loske, Achim M

    2017-01-01

    This book provides current, comprehensive, and clear explanations of the physics behind medical and biomedical applications of shock waves. Extracorporeal shock wave lithotripsy is one of the greatest medical advances of our time, and its techniques and clinical devices are continuously evolving. Further research continues to improve the understanding of calculi fragmentation and tissue-damaging mechanisms. Shock waves are also used in orthopedics and traumatology. Possible applications in oncology, cardiology, dentistry, gene therapy, cell transfection, transformation of fungi and bacteria, as well as the inactivation of microorganisms are promising approaches for clinical treatment, industrial applications and research. Medical and Biomedical Applications of Shock Waves is useful as a guide for students, technicians and researchers working in universities and laboratories. Chemists, biologists, physicians and veterinarians, involved in research or clinical practice will find useful advice, but also engineer...

  20. Relative locations of the bow shocks of the terrestrial planets

    Russell, C.T.

    1977-01-01

    The observed bow shock encounters at Mercury, Venus and Mars are least square fit using the same technique so that their sizes and shapes can be intercompared. The shock front of Mercury most resembles the terrestrial shock in shape, and the shock stand off distance is consistent with the observed moment. The shapes of the Venus and Mars shock fronts more resemble each other than the earth's and the stand off distances are consistent with direct interaction of the solar wind with the ionosphere on the dayside. The Venus shock is closer to the planet than the Mars shock suggesting more absorption of the solar wind at Venus

  1. THE EFFECTS OF AREA CONTRACTION ON SHOCK WAVE STRENGTH AND PEAK PRESSURE IN SHOCK TUBE

    A. M. Mohsen

    2012-06-01

    Full Text Available This paper presents an experimental investigation into the effects of area contraction on shock wave strength and peak pressure in a shock tube. The shock tube is an important component of the short duration, high speed fluid flow test facility, available at the Universiti Tenaga Nasional (UNITEN, Malaysia. The area contraction was facilitated by positioning a bush adjacent to the primary diaphragm section, which separates the driver and driven sections. Experimental measurements were performed with and without the presence of the bush, at various diaphragm pressure ratios, which is the ratio of air pressure between the driver (high pressure and driven (low pressure sections. The instantaneous static pressure variations were measured at two locations close to the driven tube end wall, using high sensitivity pressure sensors, which allow the shock wave strength, shock wave speed and peak pressure to be analysed. The results reveal that the area contraction significantly reduces the shock wave strength, shock wave speed and peak pressure. At a diaphragm pressure ratio of 10, the shock wave strength decreases by 18%, the peak pressure decreases by 30% and the shock wave speed decreases by 8%.

  2. Analysis in indexing

    Mai, Jens Erik

    2005-01-01

    is presented as an alternative and the paper discusses how this approach includes a broader range of analyses and how it requires a new set of actions from using this approach; analysis of the domain, users and indexers. The paper concludes that the two-step procedure to indexing is insufficient to explain...

  3. Rethinking image indexing?

    Christensen, Hans Dam

    2017-01-01

    Hans Dam Christensen, ”Rethinking image indexing?”, in: Journal of the Association for Information Science and Technology, vol. 68, no. 7, 2017, 1782-1785......Hans Dam Christensen, ”Rethinking image indexing?”, in: Journal of the Association for Information Science and Technology, vol. 68, no. 7, 2017, 1782-1785...

  4. GRI Index 2017

    World Bank

    2017-01-01

    This World Bank GRI Index 2017 provides an overview of sustainability considerations within the World Bank’s lending and analytical services as well as its corporate activities. This index of sustainability indicators has been prepared in accordance with the internationally recognized standard for sustainability reporting, the GRI Standards: Core option (https://www.globalreporting.org). T...

  5. 2016 GRI Index

    World Bank

    2016-01-01

    This 2016 World Bank Global Reporting Initiative (GRI) Index provides an overview of sustainability considerations within the World Bank’s lending and analytical services as well as its corporate activities. This index of sustainability indicators has been prepared in accordance with the internationally recognized standard for sustainability reporting GRI guidelines (https://www.globalrepo...

  6. Global Ecosystem Restoration Index

    Fernandez, Miguel; Garcia, Monica; Fernandez, Nestor

    2015-01-01

    The Global ecosystem restoration index (GERI) is a composite index that integrates structural and functional aspects of the ecosystem restoration process. These elements are evaluated through a window that looks into a baseline for degraded ecosystems with the objective to assess restoration...

  7. EJSCREEN Supplementary Indexes 2015 Public

    U.S. Environmental Protection Agency — There are 40 supplementary EJSCREEN indexes that are divided into 5 categories: EJ Index with supplementary demographic index, Supplementary EJ Index 1 with...

  8. Search for interplanetary shock signals using the Tupi telescope at the ascending phase of the solar cycle 24

    Augusto, C.R.A.; Kopenkin, V.; Navia, C.E.; Tsui, K.H.; Shigueoka, H.; Fauth, A.C.; Kemp, E.; Manganote, E.J.T.; Oliveira, M.A. Leigui de; Miranda, P.; Ticona, R.; Velarde, A.

    2012-01-01

    Full text: This paper presents the results of an on-going survey on the association between the muon flux variation at ground level registered by the Tupi telescopes (Niteroi-Brazil, 22.9 deg S; 43.2 deg W, 3 m above sea level) in the South Atlantic Anomaly (SAA) region and interplanetary shocks detected by space-borne detectors (SOHO, ACE, GOES). The SAA provides favorable conditions for observation of shock driven geomagnetic storms, including those of very small scale. Geomagnetic storms are usually originated by the transient events such as solar flares, coronal mass ejections (CMEs) and corotating interaction regions (CIRs). In most cases scientific research showed variation in the cosmic particle flux at ground level in correlation with large scale CMEs solar flares characterized by high absolute values of geomagnetic activity Kp index. In our analysis we found that the muon flux associated with the interplanetary shock signals changes also in response to low solar activity and to fast rise in Kp index. We report experimental data obtained by the Tupi telescopes in the period from June 2010 to December 2011. This time period corresponds to the rising phase of the solar cycle 24. These observations are compared with publicly available observations from the CELIAS/MTOF Proton Monitor on SOHO satellite in order to study the origin of the shocks. Among 28 interplanetary shocks reported in present analysis, there are 12 possibly associated with the CMEs and solar flares, 2 events - with the CIR related shocks (forward or reverse shocks), and the origin of the remaining 13 events has not been determined by the satellite detectors. By comparing the observed time (delayed or anticipated) of the shock related signal on Earth (the Tupi telescopes) with the trigger time of the shock registered by satellites located at the Lagrange point L1 (SOHO, ACE), we find that it is possible to estimate the type of the shock (forward or reverse). This method can be useful in

  9. Search for interplanetary shock signals using the Tupi telescope at the ascending phase of the solar cycle 24

    Augusto, C.R.A.; Kopenkin, V.; Navia, C.E.; Tsui, K.H.; Shigueoka, H. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Fisica; Fauth, A.C.; Kemp, E.; Manganote, E.J.T. [Universidade Estadual de Campinas (IFGW/UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin; Oliveira, M.A. Leigui de [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Centro de Ciencias Naturais e Humanas; Miranda, P.; Ticona, R.; Velarde, A. [Universidad Mayor de San Andres (UMSA), La Paz (Bolivia, Plurinational State of). Inst. de Investigaciones Fisicas

    2012-07-01

    Full text: This paper presents the results of an on-going survey on the association between the muon flux variation at ground level registered by the Tupi telescopes (Niteroi-Brazil, 22.9 deg S; 43.2 deg W, 3 m above sea level) in the South Atlantic Anomaly (SAA) region and interplanetary shocks detected by space-borne detectors (SOHO, ACE, GOES). The SAA provides favorable conditions for observation of shock driven geomagnetic storms, including those of very small scale. Geomagnetic storms are usually originated by the transient events such as solar flares, coronal mass ejections (CMEs) and corotating interaction regions (CIRs). In most cases scientific research showed variation in the cosmic particle flux at ground level in correlation with large scale CMEs solar flares characterized by high absolute values of geomagnetic activity Kp index. In our analysis we found that the muon flux associated with the interplanetary shock signals changes also in response to low solar activity and to fast rise in Kp index. We report experimental data obtained by the Tupi telescopes in the period from June 2010 to December 2011. This time period corresponds to the rising phase of the solar cycle 24. These observations are compared with publicly available observations from the CELIAS/MTOF Proton Monitor on SOHO satellite in order to study the origin of the shocks. Among 28 interplanetary shocks reported in present analysis, there are 12 possibly associated with the CMEs and solar flares, 2 events - with the CIR related shocks (forward or reverse shocks), and the origin of the remaining 13 events has not been determined by the satellite detectors. By comparing the observed time (delayed or anticipated) of the shock related signal on Earth (the Tupi telescopes) with the trigger time of the shock registered by satellites located at the Lagrange point L1 (SOHO, ACE), we find that it is possible to estimate the type of the shock (forward or reverse). This method can be useful in

  10. Waves and Instabilities in Collisionless Shocks

    1984-04-01

    occur in the electron foreshock and are driven by suprathermal electrons escaping into the region upstream of the shock. Both the ion-acoustic and...ULF waves occur in the ion foreshock and are associated with ions streaming into the region upstream of 11 the shock. The region downstream of the...the discussion of these waves it is useful to distinguish two regions, called the electron foreshock and the ion foreshock . Because the particles

  11. The Dynamic Quasiperpendicular Shock: Cluster Discoveries

    Krasnoselskikh, V.; Balikhin, M.; Walker, S. N.; Schwartz, S.; Sundkvist, D.; Lobzin, V.; Gedalin, M.; Bale, S. D.; Mozer, F.; Souček, Jan; Hobara, Y.; Comisel, H.

    2013-01-01

    Roč. 178, 2-4 (2013), s. 535-598 ISSN 0038-6308 Institutional support: RVO:68378289 Keywords : collisionless shocks * waves in plasmas * nonstationarity * shock scales * plasma heating and acceleration * wave-particle interactions Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 5.874, year: 2013 http://link.springer.com/article/10.1007%2Fs11214-013-9972-y

  12. Flow control for oblique shock wave reflections

    Giepman, R.H.M.

    2016-01-01

    Shock wave-boundary layer interactions are prevalent in many aerospace applications that involve transonic or supersonic flows. Such interactions may lead to boundary layer separation, flow unsteadiness and substantial losses in the total pressure. Flow control techniques can help to mitigate these adverse effects and stabilize the interaction. This thesis focuses on passive flow control techniques for oblique shock wave reflections on flat plates and presents experimental results for both la...

  13. Public Investment, Revenue Shocks, and Borrowing Restrictions

    Büttner, Thiess; Wildasin, David E.

    2010-01-01

    This paper lays out a theory of taxation and public investment in an intertemporal setting under conditions of revenue shocks. Without borrowing restrictions, the optimal policy is characterized by smooth time paths of taxes and public investment. While the introduction of formal borrowing restrictions leads to some precautionary savings, it gives rise to fluctuations in public investment in response to adverse but also favorable revenue shocks. This theoretical result is tested empirically u...

  14. Optical Probes for Laser Induced Shocks

    1992-03-01

    target by the strong water. As the shock passes the material interface, it is pressure transients. only partially transmitted. The shock pressure is...T. Swimm , J. Appl. Phys. 61, evaporated, t1137(1987). vapor flow substantially. The coupling coefficient thus de- 3 v. A. Batanov and V. B. Fedorov...Waist-Surface Distance [mm] isurface on the drilling mechanismC Positive ( negative ) To roughly estimate the total recoil momentum positions

  15. Fast Electrocardiogram Amplifier Recovery after Defibrillation Shock

    Ivan Dotsinsky

    2005-04-01

    Full Text Available A procedure for fast ECG amplifier recovery after defibrillation shocks was developed and simulated in the MATLAB environment. Exponentially decaying post-shock voltages have been recorded. Signals from the AHA database are taken and mixed with the recorded exponential disturbances. The algorithm applies moving averaging (comb filter on the compound input signal, thereby obtaining the samples of the disturbance. They are currently subtracted from the input signal. The results obtained show that its recovery is practically instantaneous.

  16. Pressurized-thermal-shock experiments

    Whitman, G.D.; McCulloch, R.W.

    1982-01-01

    The primary objective of the ORNL pressurized-thermal-shock (PTS) experiments is to verify analytical methods that are used to predict the behavior of pressurized-water-reactor vessels under these accident conditions involving combined pressure and thermal loading. The criteria on which the experiments are based are: scale large enough to attain effective flaw border triaxial restraint and a temperature range sufficiently broad to produce a progression from frangible to ductile behavior through the wall at a given time; use of materials that can be completely characterized for analysis; stress states comparable to the actual vessel in zones of potential flaw extension; range of behavior to include cleavage initiation and arrest, cleavage initiation and arrest on the upper shelf, arrest in a high K/sub I/ gradient, warm prestressing, and entirely ductile behavior; long and short flaws with and without stainless steel cladding; and control of loads to prevent vessel burst, except as desired. A PTS test facility is under construction which will enable the establishment and control of wall temperature, cooling rate, and pressure on an intermediate test vessel (ITV) in order to simulate stress states representative of an actual reactor pressure vessel

  17. A FOCUSED TRANSPORT APPROACH TO THE TIME-DEPENDENT SHOCK ACCELERATION OF SOLAR ENERGETIC PARTICLES AT A FAST TRAVELING SHOCK

    Le Roux, J. A.; Webb, G. M.

    2012-01-01

    Some of the most sophisticated models for solar energetic particle (SEP) acceleration at coronal mass ejection driven shocks are based on standard diffusive shock acceleration theory. However, this theory, which only applies when SEP pitch-angle anisotropies are small, might have difficulty in describing first-order Fermi acceleration or the shock pre-heating and injection of SEPs into first-order Fermi acceleration accurately at lower SEP speeds where SEP pitch-angle anisotropies upstream near the shock can be large. To avoid this problem, we use a time-dependent focused transport model to reinvestigate first-order Fermi acceleration at planar parallel and quasi-parallel spherical traveling shocks between the Sun and Earth with high shock speeds associated with rare extreme gradual SEP events. The focused transport model is also used to investigate and compare three different shock pre-heating mechanisms associated with different aspects of the nonuniform cross-shock solar wind flow, namely, the convergence of the flow (adiabatic compression), the shear tensor of the flow, and the acceleration of the flow, and a fourth shock pre-heating mechanism associated with the cross-shock electric field, to determine which pre-heating mechanism contributes the most to injecting shock pre-heated source particles into the first-order Fermi acceleration process. The effects of variations in traveling shock conditions, such as increasing shock obliquity and shock slowdown, and variations in the SEP source with increasing shock distance from the Sun on the coupled processes of shock pre-heating, injection, and first-order Fermi acceleration are analyzed. Besides the finding that the cross-shock acceleration of the solar wind flow yields the dominant shock pre-heating mechanism at high shock speeds, we find that first-order Fermi acceleration at fast traveling shocks differs in a number of respects from the predictions and assumptions of standard steady-state diffusive shock

  18. Thermal shock investigation of silicon nitride

    Ziegler, G.; Leucht, R.

    1977-01-01

    In this work, the thermal shock properties of commercial reaction-bonded Si 3 N 4 quality material (RBSN), of commercial hot-pressed Si 3 N 4 (HPSN) and of different laboratory grades of hot-pressed Si 3 N 4 were examined. The thermal shock properties of RBSN quality material differ according to the structure considerably: The critical temperature difference for sample crossections of 5 x 5 or 6 x 6 mm after quenching in oil lies between 730 0 C and over 1400 0 C. The best thermal shock properties are shown by high density RBSN quality material having very fine pores and high initial strength. The results indicate that for RBSN large pores and density inhomogenities are responsible for bad thermal shock properties. Resistance to fast temperature change is higher for hot-pressed Si 3 N 4 than for RBSN quality material. In HPSN, the thermal shock results show dependence on structure. High MgO content and the associated coarse rod-shaped configuration of the β phase and structural inhomogenities affect the thermal shock properties in an adverse way. (orig.) [de

  19. Mechanical Properties of Shock-Damaged Rocks

    He, Hongliang; Ahrens, T. J.

    1994-01-01

    Stress-strain tests were performed both on shock-damaged gabbro and limestone. The effective Young's modulus decreases with increasing initial damage parameter value, and an apparent work-softening process occurs prior to failure. To further characterize shock-induced microcracks, the longitudinal elastic wave velocity behavior of shock-damaged gabbro in the direction of compression up to failure was measured using an acoustic transmission technique under uniaxial loading. A dramatic increase in velocity was observed for the static compressive stress range of 0-50 MPa. Above that stress range, the velocity behavior of lightly damaged (D(sub 0) less than 0.1) gabbro is almost equal to unshocked gabbro. The failure strength of heavily-damaged (D(sub 0) greater than 0.1) gabbro is approx. 100-150 MPa, much lower than that of lightly damaged and unshocked gabbros (approx. 230-260 MPa). Following Nur's theory, the crack shape distribution was analyzed. The shock-induced cracks in gabbro appear to be largely thin penny-shaped cracks with c/a values below 5 x 10(exp -4). Moreover, the applicability of Ashby and Sammis's theory relating failure strength and damage parameter of shock-damaged rocks was examined and was found to yield a good estimate of the relation of shock-induced deficit in elastic modulus with the deficit in compressive strength.

  20. Emissive spectra of shock-heated argon

    Tang Jingyou; Gu Yan; Peng Qixian; Bai Yulin; Li Ping

    2003-01-01

    To study the radiant properties of argon under weak shock compression, an aluminum target filled with gaseous argon at ambient states was impacted by a tungsten alloy projectile which was launched from a two-stage light gun to 2.00 km/s. The radiant signals of single shock-compressed argon were recorded by a six-channel pyrometer and oscilloscopes, which varied with time linearly for the five channels from 405 nm to 700 nm and exponentially for the channel 800 nm, and the corresponding velocity of shock wave was determined to be 4.10 ± 0.09 km/s. By the present experiment, it has been shown that the absorbability of the shock-heated argon is low for visual light and the optical depths of argon gas turn from thin to thick as wavelengths gradually increase. The time-resolved spectra in the rising-front of the radiant signal in the re-shocked argon were recorded by means of an OMA, and strong emissive spectrum bands near 450 nm light-wave length but no linear spectrum were found. The emissive spectrum properties of shock-compression argon were qualitatively explained by the state parameters and ionization degree