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31.
Friedman Sara R.; Rapport Lisa J.; Lumley Mark; Tzelepis Angela; VanVoorhis Amy; Stettner Lawrence; Kakaati Laura 《Canadian Metallurgical Quarterly》2003,17(1):50
Social and emotional competence were evaluated using self-report and behavioral measures in adults with attention-deficit/hyperactivity disorder (ADHD) and controls. Adults with ADHD viewed themselves as less socially competent but more sensitive toward violations of social norms than controls. Films depicting emotional interactions were used to assess linguistic properties of free recall and perceived emotional intensity. Although adults with ADHD used more words to describe the scenes, they used fewer emotion-related words, despite rating the emotions depicted as more intense than did controls. In contrast, no group differences for words depicting social or cognitive processes were observed. Overall, adults with ADHD appear more aware of their problems in social versus emotional skills. Findings may have implications for improving the psychosocial functioning of these adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Many research projects require accurate delineation of different secondary succession (SS) stages over large regions/subregions of the Amazon basin. However, the complexity of vegetation stand structure, abundant vegetation species, and the smooth transition between different SS stages make vegetation classification difficult when using traditional approaches such as the maximum likelihood classifier (MLC). Most of the time, classification distinguishes only between forest/non-forest. It has been difficult to accurately distinguish stages of SS. In this paper, a linear mixture model (LMM) approach is applied to classify successional and mature forests using Thematic Mapper (TM) imagery in the Rondônia region of the Brazilian Amazon. Three endmembers (i.e., shade, soil, and green vegetation or GV) were identified based on the image itself and a constrained least-squares solution was used to unmix the image. This study indicates that the LMM approach is a promising method for distinguishing successional and mature forests in the Amazon basin using TM data. It improved vegetation classification accuracy over that of the MLC. Initial, intermediate, and advanced successional and mature forests were classified with overall accuracy of 78.2% using a threshold method on the ratio of shade to GV fractions, a 7.4% increase over the MLC. The GV and shade fractions are sensitive to the change of vegetation stand structures and better capture biophysical structure information. 相似文献
33.
Duan-Shin Lee Benjamin Melamed Amy R. Reibman Bhaskar Sengupta 《Performance Evaluation》1992,16(1-3):21-34
The transport of video images is likely to be a major application of high-speed networks of the future. These applications are capable of utilizing the high bandwidths that will become available with the advent of B-ISDN. In this paper, we propose a new methodology (called TES) for modeling the frame bitrate stream generated by compressed video sources. The main characteristic of this method is that it can model an arbitrary marginal distribution and approximate the autocorrelation structure of the random bitrate process generated by compressed frames. We present a modeling example utilizing this method, based on data from a video coding algorithm employing a layering technique. Using the source model, we develop a simulation model of a multiplexer of video sources. We show that this model can be used to address a number of design issues that arise in this class of problem. In particular, we show that for a layered video coding algorithm, it is possible to have a gain in the number of sources multiplexed at the cost of some loss of low priority packets. 相似文献
34.
Eleven Spectralon1 (a sintered polytetrafluoroethylene-based material) and 16 BaSO4 reference reflectance panels were calibrated using a field calibration technique. The Spectralon panels differed both in their directional/hemispherical and directional/directional reflectance. However, the differences were sufficiently small that “general” calibration equations were developed. For panels constructed of the same material and with the same methods as those used in these experiments, the directional/directional reflectance may be within ± 0.020 at 10°, ± 0.015 at 45°, and ± 0.041 at 80° of that predicted by the “general” equations. For field measurements, these values are considerably better than those that would be obtained using a value of the directional/hemispherical reflectance. The directional/directional reflectance of the 16 BaSO4 panels varied considerably among panels, so much so that it was not feasible to develop “general” calibration equations. Apparently, the nonlambertian properties of BaSO4 panels are dependent upon the method of applying the barium sulfate coating. 相似文献
35.
Amy Neustein 《International Journal of Speech Technology》2006,9(3-4):109-120
This paper will demonstrate how Sequence Package Analysis, as a new natural language understanding method that is built on a set of parsing structures that consist of context-free grammatical units and related prosodic features for identifying affective/emotional data found in natural speech and blogs, may better accommodate the goals of crisis management and rapid decision making in critical systems. Following an in depth discussion of the genesis and development of this method for the design of voice-user interfaces and audio mining programs, debuted in an earlier issue of IJST, this paper will attempt to show how Sequence Package Analysis can improve human response in monitoring recorded conversations of terror suspects and the recordings of help-line desks. In both instances, effective human intervention may help avert a crisis and resulting liability. The paper’s limited focus on these two respective domains does not, however, limit the applicability of Sequence Package Analysis to other critical systems, inasmuch as the parsing structures explained below are generic enough to be applied to other critical systems, such as ambulance control, aircraft or nuclear power stations, or 911 calls for help. Given that critical systems require effective human response from decision makers, natural language data must be accorded the same kind of scientific scrutiny given to graphic design and other features of human-computer interaction. 相似文献
36.
In this paper we explore the idea of aggression as a defence against threats to the psychological self. This aspect of the self allows reflection about people in psychological terms and develops, in the first three years of life, through appreciation of mental states in the other. When the object is unpredictable or hostile, recognition of this is painful to the child, and his reflective function will not be adequately established. The defences of aggression or avoidance will be invoked very frequently. In time, aggression may become an organising influence in the construction of the self; pathological destructiveness then takes the place of emotional relatedness and concern for the other. Psychoanalytic treatment no longer works primarily by addressing conflict. Instead, particularly through interpretations of transference and countertransference, the analyst recreates an intersubjective process which enhances the patient's reflective self, this time in the safety of a benign relationship. 相似文献
37.
Babbs C.F. Fearnot N.E. Marchosky J.A. Moran C.J. Jones J.T. Plantenga T.D. 《IEEE transactions on bio-medical engineering》1990,37(7):662-672
This paper describes simulation of steady-state intratumoral temperatures achieved by a simple modality of local heat therapy: interstitial treatment with parallel arrays of warmed, conductive heating elements. During "conductive heating" power is directly deposited only in the interstitial probes. Adjacent tissue is warmed by heat conduction. Simulations of interstitial conductive heating involved solution of the bioheat transfer equation on a digital computer using a finite difference model of the treated tissue. The simulations suggest that when the complete temperature distributions for conductive interstitial hyperthermia are examined in detail, substantial uniformity of the temperature distributions is evident. Except for a thin sleeve of tissue surrounding each heating element, a broad, flat central valley of temperature elevation is achieved, with a well defined minimum temperature, very close to modal and median tissue temperatures. Because probes are inserted directly in tumor tissue, the thin sleeve of overheated tissue would not be expected to cause normal tissue complications. The temperature of the heated probes must be continuously controlled and increased in the face of increased blood flow in order to maintain minimum tumor temperature. However, correction for changes in blood flow is possible by adjusting probe temperature according to a feedback control scheme, in which power dissipation from each probe is the sensed input variable. Conductive interstitial heating with continually controlled probe temperature deserves investigation as a technique for local hyperthermia therapy. 相似文献
38.
A technique for estimating and correcting nonuniform sampling distortions in magnetic resonance imagery is presented. The technique consists of first estimating the sampling grid distortion using a parametric model, and then estimating the uniformly sampled data by interpolation on the nonuniform grid. Parameterized models for two particular sampling grid distortion are presented. Maximum likelihood and maximum a posteriori estimators are developed for these distortions. Using computer simulated data, these estimators are shown to perform well. 相似文献
39.
This paper describes four investigations of the olfactory mucosa of the brown trout: 1) the ultrastructure of the olfactory mucosa as revealed by scanning (SEM), conventional transmission (TEM), and high voltage (HVEM) electron microscopy; 2) light and electron-microscopic investigations of retrograde transport of the tracer macromolecule horseradish peroxidase (HRP) when applied to the cut olfactory nerve; 3) SEM and TEM investigations of the effects of olfactory nerve transection on cell populations within the olfactory epithelium; and 4) ultrastructural investigations of reversible degeneration of olfactory receptors caused by elevated copper concentrations. The trout olfactory epithelium contains five cell types: ciliated epithelial cells, ciliated olfactory receptor cells, microvillar olfactory receptor cells, supporting cells, and basal cells. The ciliated and microvillar olfactory receptor cells and a small number of basal cells are backfilled by HRP when the tracer is applied to the cut olfactory nerve. When the olfactory nerve is cut, both ciliated and microvillar olfactory receptor cells degenerate within 2 days and are morphologically intact again within 8 days. When wild trout are taken from their native stream and placed in tanks with elevated copper concentrations, ciliated and microvillar cells degenerate. Replacement of these trout into their stream of origin is followed by morphologic restoration of both types of olfactory receptor cells. Ciliated and microvillar receptor cells are primary sensory bipolar neurons whose dendrites make contact with the environment; their axons travel directly to the brain. Consequently, substances can be transported directly from the environment into the brain via these "naked neurons." Since fish cannot escape from the water in which they swim, and since that water may occasionally contain brain-toxic substances, the ability to close off--and later reopen--this anatomic gateway to the brain would confer a tremendous selective advantage upon animals that evolved the "brain-sparing" capacity to do so. Consequently, the unique regenerative powers of vertebrate olfactory receptor neurons may have their evolutionary origin in fishes. 相似文献
40.
Amy?Richards Chakra?WijesunderaEmail author Phil?Salisbury 《Journal of the American Oil Chemists' Society》2005,82(12):869-874
Lipid oxidation is a major factor affecting flavor quality and shelf life of vegetable oils. Oxidative stability is therefore
an important criterion by which oils are judged for usefulness in various food applications. In this study a method based
on headspace analysis was developed to evaluate relative oxidative stability of canola oils. The method does not require the
use of chemicals, involves minimal sample preparation, and can be performed on a relatively small sample size in comparison
with traditional wet chemical methods. Canola oils freshly extracted in the laboratory from different seed samples were subjected
to accelerated oxidation and analyzed for PV by standard methods and headspace volatiles by solid phase microextraction/GC-MS.
Forward stepwise regression analysis of the data revealed a relationship between PV and headspace concentration of the volatile
lipid oxidation products hexanal and trans,trans-2,4-heptadienal. The PV calculated using this formula correlated (R
2=0.73) with those measured by conventional methods.
Presented in part at the 96th Annual Meeting of the AOCS, 1–4 May 2005, Salt Lake City, UT. 相似文献