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排序方式: 共有533条查询结果,搜索用时 15 毫秒
1.
Carels Robert A.; Cacciapaglia Holly; Pérez-Benítez Carlos I.; Douglass Olivia; Christie Samantha; O'Brien William H. 《Canadian Metallurgical Quarterly》2003,71(4):753
Reports an error in the original article by R. A. Carels et al (Journal of Consulting & Clinical Psychology, 2003[Jun], Vol 71[3], 613-618). On page 615, Lines 18, 20, 22, of Table 1, the data in the rows that read "Tachycardia in min per hr," "Repetitive PVCs per hr," and "PVCs per hr" are incorrectly reported in the n and % columns. They should have been reported in the M and SD columns. The corrected table is provided. (The following abstract of this article originally appeared in record 2003-00756-023.) Ventricular arrhythmia exhibits considerable within-subject variability that cannot be attributed to clinical status alone. This investigation examined the extent to which cardiac arrhythmia was associated with psychological and physical factors assessed during the hour preceding arrhythmic or nonarrhythmic activity. Approximately twice hourly, 46 patients randomly completed a diary assessing mood and physical symptoms during 24-hr electrocardiographic monitoring. Greater negative emotion was associated with increased arrhythmia. Additionally, greater negative emotion was significantly associated with increased arrhythmia among participants in a low left ventricular ejection fraction group (LVEF). However, this relationship between negative emotion and arrhythmia was not... (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Pin Yang Carolina A. Gomez Samantha Andrews Josef D. Sorenson Ken S. Chen 《Journal of the American Ceramic Society》2021,104(7):3247-3259
The electric discharge across a varistor granule filled air gap under a fast-rising voltage pulse was investigated for surge protection applications. The effects of temperature and pressure on the arc and the electrical conduction were analyzed by the characteristic changes in voltage waveforms triggered by a fast-rising high voltage pulse. In addition to the gap size, experimental results show that competing mechanisms among arc conduction, conduction through the varistor granule network, thermionic emission from Joule heating at granule-to-granule contact points, and the magnitude of the switching voltage dictate the maximum surge protection voltage for the filled air gap. Experimental evidence indicated that accumulated degradation was created at small contact points between varistor granules by repetitive assaults from longer duration, high voltage pulses. The uniqueness of using varistor over other dielectric granules in an air gap for surge protection is identified and discussed. 相似文献
3.
Manipulating Electrical and Fluidic Access in Integrated Nanopore‐Microfluidic Arrays Using Microvalves 下载免费PDF全文
4.
Allan James Samantha Low Choy Kerrie Mengersen 《Environmental Modelling & Software》2010,25(1):129-145
Expert elicitation is the process of retrieving and quantifying expert knowledge in a particular domain. Such information is of particular value when the empirical data is expensive, limited or unreliable. This paper describes a new software tool, called Elicitator, which assists in quantifying expert knowledge in a form suitable for use as a prior model in Bayesian regression. Potential environmental domains for applying this elicitation tool include habitat modelling, assessing detectability or eradication, ecological condition assessments, risk analysis and quantifying inputs to complex models of ecological processes. The tool has been developed to be user-friendly, extensible and facilitate consistent and repeatable elicitation of expert knowledge across these various domains. We demonstrate its application to elicitation for logistic regression in a geographically based ecological context. The underlying statistical methodology is also novel, utilizing an indirect elicitation approach to target expert knowledge on a case-by-case basis. For several elicitation sites (or cases), experts are asked simply to quantify their estimated ecological response (e.g. probability of presence), and its range of plausible values, after inspecting (habitat) covariates via GIS. 相似文献
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6.
NOAA Radios and Neighbourhood Networks: Demographic Factors for Channel Preference for Hurricane Evacuation Information 下载免费PDF全文
Sarah E. DeYoung Tricia Wachtendorf Ashley K. Farmer Samantha C. Penta 《突发事故与危机管理杂志》2016,24(4):275-285
This paper reviews literature on information channel type and disasters, and presents results on hurricane evacuation information gathering. Results show that respondents reported they would use television and radio most frequently for gathering information about hurricane evacuation. Minority respondents reported more preference of the use of community or local government as information sources than white respondents, females gathered information from multiple channels more than males, and younger residents gathered information from multiple channels more than older respondents. Implications include areas for future research in how channel utilization occurs during slow onset hazards in predominantly black communities, how age and gender relate to channel preference, and how channel preferences affect length of time to make decisions and engage in protective actions. 相似文献
7.
Robert J.W. Brewin Nick J. Hardman-Mountford Samantha J. Lavender Dionysios E. Raitsos Takafumi Hirata Julia Uitz Annick Bricaud Bernard Gentili 《Remote sensing of environment》2011,115(2):325-339
Satellite remote sensing of ocean colour is the only method currently available for synoptically measuring wide-area properties of ocean ecosystems, such as phytoplankton chlorophyll biomass. Recently, a variety of bio-optical and ecological methods have been established that use satellite data to identify and differentiate between either phytoplankton functional types (PFTs) or phytoplankton size classes (PSCs). In this study, several of these techniques were evaluated against in situ observations to determine their ability to detect dominant phytoplankton size classes (micro-, nano- and picoplankton). The techniques are applied to a 10-year ocean-colour data series from the SeaWiFS satellite sensor and compared with in situ data (6504 samples) from a variety of locations in the global ocean. Results show that spectral-response, ecological and abundance-based approaches can all perform with similar accuracy. Detection of microplankton and picoplankton were generally better than detection of nanoplankton. Abundance-based approaches were shown to provide better spatial retrieval of PSCs. Individual model performance varied according to PSC, input satellite data sources and in situ validation data types. Uncertainty in the comparison procedure and data sources was considered. Improved availability of in situ observations would aid ongoing research in this field. 相似文献
8.
Aging and imperfections provide important visual cues for realism. We present a novel physically‐based approach for simulating the biological aging and decay process in fruits. This method simulates interactions between multiple processes. Our biologically‐derived, reaction‐diffusion model generates growth patterns for areas of fungal and bacterial infection. Fungal colony spread and propagation is affected by both bacterial growth and nutrient depletion. This process changes the physical properties of the surface of the fruit as well as its internal volume substrate. The fruit is physically simulated with parameters such as skin thickness and porosity, water content, flesh rigidity, ambient temperature, humidity, and proximity to other surfaces. Our model produces a simulation that closely mirrors the progression of decay in real fruits under similar parameterized conditions. Additionally, we provide a tool that allows artists to customize the input of the program to produce generalized fruit simulations. 相似文献
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10.
Effect of section width and casting rate on variations of formwork pressure of self-consolidating concrete 总被引:2,自引:0,他引:2
The influence of formwork dimensions and rate of casting of self-consolidating concrete (SCC) on the development and variations of lateral pressure were evaluated using two types of experimental columns; the first measuring 2100 mm in height and 200 mm in diameter, and the second 3600 mm in height and 920 mm in diameter. Variations of heat of hydration and setting time were correlated to the rate of decrease in formwork pressure.Test results show that the scale effect has an influence on the rate of drop in lateral pressure with time. Two distinctive rates of pressure drop were obtained during the plastic and setting stages of hydration. A rate of pressure decrease of 5.3 kPa/hr was obtained during the first 6 hours of time and is mostly associated with the increase in the restructuring process due to the reversible effect of thixotropy. A second distinctive slope of 2 kPa/hr was noted beyond 6 hours until the canceling of pressure, and is related to setting. The increase in the casting rate from 10 to 25 m/hr in the 200-mm diameter column resulted in slightly higher lateral pressure. 相似文献