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81.
Abstract Proper classification and terminology comprise an essential basis for avoiding confusion or imprecision. Classification will assist in recording available data, setting up a global database and developing predictive relationships. In this paper, an attempt to develop a well‐accepted classification of and terminology for food properties is made. The proposed four classes of food properties are: physical and physico‐chemical properties, kinetic properties, sensory properties, and health properties. 相似文献
82.
The concatenation of an equalizer and a Viterbi (1967) decoder is a powerful means for improving receiver performance in wireless communication systems. A soft-output equalizer increases the impact of this combination by enabling the use of soft-decision Viterbi decoding. It is well known that the maximum a posteriori (MAP) algorithm provides optimal reliability information, but at the cost of substantial complexity. This paper contains the results of an investigation into the design and performance of soft-output adaptive equalization techniques based on suboptimum trellis-based soft-output decoding algorithms. It is shown that the performance improvement relative to hard output equalizers is substantial, while the cost in terms of complexity is modest. A time-division multiple-access (TDMA) cellular system is used as the basis for comparisons. Simulation results and a complexity analysis are presented 相似文献
83.
Wade Shari L.; Taylor H. Gerry; Walz Nicolay Chertkoff; Salisbury Shelia; Stancin Terry; Bernard Lori A.; Oberjohn Karen; Yeates Keith Owen 《Canadian Metallurgical Quarterly》2008,53(2):180
Objective: To understand how traumatic brain injury (TBI) affects parent-child interactions acutely following injury. Participants: Young children hospitalized for TBI (n = 80) and orthopedic injuries (OI; n = 113). Method: Raters coded videotaped interactions during free play and structured tasks for parental warmth/responsiveness and negativity and child warmth, behavior regulation, and cooperation. Raters also counted parental directives, critical/restricting statements, and scaffolds. Results: Parents of children with TBI exhibited less warm responsiveness and made more directive statements during a structured task than parents in the OI group. Children with TBI displayed less behavior regulation than children with OI. Parental warm responsiveness was more strongly related to child cooperativeness in the OI group than in the TBI group. Child behavior also mediated group differences in parental responsiveness and directiveness. TBI accounted for as much variance in parental behaviors as or more than did sociodemographic factors. Conclusion: TBI-related changes in child behavior may negatively influence parent-child interactions and disrupt the reciprocity between parent and child. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
ABET Engineering Criteria 2000 require a selection of outcomes and outcome indicators for each educational objective adopted by an engineering program. This paper describes a database created using Microsoft Access 97 © linking choices of program outcomes and choices of program outcome indicators for all of the accredited engineering programs in an academic institution. With this database, benchmarking searches can be conducted by type of engineering program, by choice of outcome, or by choice of outcome indicator. Several example searches are presented using data describing the engineering programs at Clemson University. A web-site address is given where copies of the Clemson database can be downloaded. 相似文献
85.
Occurrence and recurrences of suicidal ideation (SI) were modeled among boys/men assessed annually from ages 12 to 29 years. Multiple-spell discrete-time event-history analyses permitted (a) determination of whether risk for SI escalates with prior experiences of SI (spell effects), while (b) accounting for changes in risk with time (period effects) and (c) controlling for vulnerability factors. Self-reported SI (presence/absence in past week), depressive symptoms, alcohol/substance use, antisocial behavior, and official arrest records were collected annually from 205 boys recruited on the basis of community risk for delinquency. Parents' self-reported psychopathology and SES were collected in childhood. Period effects supported decreasing risk for SI over time. Spell and time-varying 1-year lagged substance use and depressive symptoms independently predicted increased risk for SI. Models involving SI with intent were explored. Consistent with interpersonal psychological theory, risk for young men's SI increases with past experience of SI, even with key propensities controlled. However, risk also decays over time. Targeting conditions that confer risk for SI is essential. Preventing and delaying SI occurrence and recurrence may represent independent mechanisms by which prevention efforts operate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Sharifzadeh S. Koehler J.R. Owen A.B. Shott J.D. 《Semiconductor Manufacturing, IEEE Transactions on》1989,2(3):82-93
The authors describe a response surface design methodology based on process and device simulations to estimate device variations due to changes in process input parameters from their designed values. The gradient of the simulated device characteristics is estimated directly and used to compute device sensitivities. This methodology was applied to Stanford's 2-μm CMOS fabrication process. Threshold voltage, subthreshold slope, linear transconductance, and saturation current were picked as the target device characteristics for optimization. Five process parameters were examined: boron concentration in the wafer, phosphorous n-well implant dose, boron threshold adjust dose, gate oxidation temperature, and gate length. The methodology was shown to be successful for the exploration of device characteristic values as a function of process parameters, but success for the transmitted variability, because it depends on derivatives which tend to be less like polynomials than the functions themselves, is more limited. In the absence of a direct assessment of the derivative, response surface models fit to the simulator values can give a very misleading picture of the transmitted variability. Models used were quadratic models for Box-Cox transformed device characteristics 相似文献
87.
Owen I. Corrigan 《Drug development and industrial pharmacy》1986,12(11):1777-1793
Molecular weight is an important determinant of plyethylene glycol (PEG) dissolution rate: the rate decreasing as the molecular weight is increased. PEG samples of equivalent nominal. molecular weight had different dissolution properties. Intrinsic viscosity and differential scanning calorimetry suggested that the observed differences my be related to molecular weight variation between samples. The dissolution rate of PEG from solid dispersions is retarded, the effect being dependent on the chemical nature of the drug and its concentration. Phenobarbitone was particularly potent in retarding PEG dissolution. Phenobarbitone dissolution rate was retarded from dispersions of high phenobarbitone content. However drug dissolution from solid dispersions low in phenobarbitone were greater than that of pure phenobarbitone. The low dissolution rates were explained in terms of formation of the 2:1 PEG monomer: phenobarbitone complex during solid dispersion formation. At high PEG weight fractions (i.e. 30:1, 50:1) drug dissolution was carrier controlled and although PEG dissolution was greatly suppressed, it was sufficiently large to transport the drug into solution at a rate greater than that of pure phenobarbitone. 相似文献
88.
Clarke-Stewart K. Alison; Vandell Deborah L.; McCartney Kathleen; Owen Margaret T.; Booth Cathryn 《Canadian Metallurgical Quarterly》2000,14(2):304
Data from the National Institute of Child Health and Human Development Study of Early Child Care were analyzed to explore effects of marital separation on children in the first 3 years of life. The sample included 73 never-married mothers and 97 separated mothers; a comparison group of 170 was conditionally randomly selected from the 2-parent families. Children in 2-parent families performed better than children in 1-parent families on assessments of cognitive and social abilities, problem behavior, attachment security, and behavior with mother. However, controlling for mothers' education and family income reduced these differences, and associations with separated-intact marital status were nonsignificant (the effect size was .01). Thus, children's psychological development was not affected by parental separation per se; it was related to mothers' income, education, ethnicity, childrearing beliefs, depressive symptoms, and behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
C. C. Owen 《Journal of the Institute of Brewing》1987,93(1):37-41
The growth of the brewing industry in Burton on Trent from the eleventh century in Burton Abbey is traced through the many phases of development to the present day. 相似文献
90.
A biomechanical and ergonomic evaluation of patient transferring tasks: wheelchair to shower chair and shower chair to wheelchair. 总被引:2,自引:0,他引:2
A laboratory study was conducted to evaluate five different manual techniques (two-person manual lifting; rocking and pulling the patient using a gait belt with two persons; walking belt with one and two persons) and three different mechanical hoists (Hoyer lift, Trans-Aid and Ambulift) for transferring patients from wheelchair to shower chair and shower chair to wheelchair. Six female nursing students with prior patient transfer experience served both as nurses and as passive patients. Static biomechanical evaluation showed that the mean trunk flexion moments, erector spinae muscle forces and compressive and shear forces at the L5S1 disc for the four pulling methods ranged from 92 to 125 Nm, 1845 to 2507 N, 1973 to 2641 N and 442 to 580 N, respectively, as compared to about 213 Nm, 4260 N, 5050 N and 926 N for two-person manual lifting. Perceived stress ratings for the shoulder, upper back, lower back and whole body were significantly lower for pulling methods than those for lifting the patient (p less than or equal to 0.01). Patients found pulling techniques, except the gait belt, to be more comfortable and secure than the lifting method (p less than or equal to 0.01). However, most of the nurses believed that Medesign and the one-person walking belt would not work on those patients who cannot bear weight and those who are heavy, contracted or combative. A two-person walking belt was the most preferred method. Two out of three hoists (Hoyer lift and Trans-Aid) were perceived by the nurses to be more stressful than one- and two-person walking belts. The patients found these two hoists to be more uncomfortable and less secure than with three of the five manual methods (one- and two-person walking belts and Medesign). Pulling techniques and hoists took significantly longer amounts of time to make the transfer than manually lifting the patient (p less than or equal to 0.01). The two-person walking belt, using a gentle rocking motion to utilize momentum and a pulling technique, and Ambulift are recommended for transferring patients from wheelchair to shower chair and shower chair to wheelchair. 相似文献