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971.
Explored how older adults recall the traits they possessed at an earlier age. It was hypothesized that older adults' recollections would be related to their theories about aging. In Study 1, a group of older Ss provided their theories concerning how various traits change with age. Another group of older Ss rated their current status on these traits and recalled the status they possessed at a younger age. In addition, a group of younger adults rated their current status on the same traits. On traits theorized to increase with age, older Ss recalled themselves as possessing lower levels at an earlier age than the younger group reported possessing. On traits theorized to decrease with age, older Ss recalled themselves as possessing higher levels at an earlier age than the younger group reported possessing. Study 2 indicated that this effect is obtained regardless of trait positivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
972.
Discordance of databases designed for claims payment versus clinical information systems. Implications for outcomes research 总被引:6,自引:0,他引:6
JG Jollis M Ancukiewicz ER DeLong DB Pryor LH Muhlbaier DB Mark 《Canadian Metallurgical Quarterly》1993,119(8):844-850
OBJECTIVE: To determine the suitability of insurance claims information for use in clinical outcomes research in ischemic heart disease. DESIGN: Concordance study of two databases. SETTING: Tertiary care referral center. PATIENTS: A total of 12,937 consecutive patients hospitalized for cardiac catheterization for suspected ischemic heart disease between July 1985 and May 1990. INTERVENTIONS: Two-by-two tables were used to compute overall and kappa measures of agreement comparing clinical versus claims data for 12 important predictors of prognosis in patients with ischemic heart disease. MEASUREMENTS: Kappa statistics (agreement adjusted for chance agreement) were used to quantify agreement rates. RESULTS: Agreement rates between the clinical and claims databases ranged from 0.83 for the diagnosis of diabetes to 0.09 for the diagnosis of unstable angina (kappa values). Claims data failed to identify more than one half of the patients with prognostically important conditions, including mitral insufficiency, congestive heart failure, peripheral vascular disease, old myocardial infarction, hyperlipidemia, cerebrovascular disease, tobacco use, angina, and unstable angina, when compared with the clinical information system. CONCLUSIONS: Our results suggest that insurance claims data lack important diagnostic and prognostic information when compared with concurrently collected clinical data in the study of ischemic heart disease. Thus, insurance claims data are not as useful as clinical data for identifying clinically relevant patient groups and for adjusting for risk in outcome studies, such as analyses of hospital mortality. 相似文献
973.
In this article, we review unsupervised neural network learning procedures which can be applied to the task of preprocessing raw data to extract useful features for subsequent classification. The learning algorithms reviewed here are grouped into three sections: information-preserving methods, density estimation methods, and feature extraction methods. Each of these major sections concludes with a discussion of successful applications of the methods to real-world problems.The first author is supported by research grants from the James S. McDonnell Foundation (grant #93–95) and the Natural Sciences and Engineering Research Council of Canada. For part of this work, the second author was supported by a Temporary Lectureship from the Academic Initiative of the University of London, and by a grant (GR/J38987) from the Science and Engineering Research Council (SERC) of the UK. 相似文献
974.
Rudisill John R.; Hempy Paula E.; Eddy Mark F.; Zimmerman Gretchen L.; Rudisill Teresa L. 《Canadian Metallurgical Quarterly》1998,50(1):36
Outlines a psychological procedure aimed at improving the working relationship between a newly hired executive and the executive's reporting official. The "Executive Fit Rehearsal" (EFR) attempts to systematically engage the executive and reporting official in a dialogue designed to anticipate and overcome problems resulting from individual differences in personality, expectations, work styles, and communication patterns. The procedure supports consensus and mutual understanding. To assess the effectiveness of the procedure, evaluation forms were mailed to participants of 15 consecutive Executive Fit sessions. Ss' reactions to the EFR indicate that the process facilitated adjustment to the work setting and improved communications. Comments from subordinates were more uniformly positive, suggesting that the process may be most helpful for new employees. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
975.
Real-time multimedia communication applications demand performance requirements which differ significantly from conventional data communication applications. Current local area networks (LANs) provide efficient transport for bursty data traffic; however, they cannot necessarily provide quality of service guarantees for real-time communications. In this work we introduce and investigate an experimental priority protocol for supporting real-time communication on Ethernet, a popular implementation of multiple-access broadcast bus LANs. We examine the new protocol, known as Priority Mode-CSMA/CD (PM-CSMA/CD), providing a high priority (HP) class with CSMA/CD employed for standard priority (SP) traffic. PM-CSMA/CD performance is examined through computer simulation of videotelephony workstations operating over the shared bus LAN. Over all observed traffic conditions, the priority protocol provides performance satisfying real-time packet transport requirements of audio and video streams. The primary advantage of our protocol over similar priority schemes is its physical layer compatibility with standard CSMA/CD. The protocol also provides improved channel utilization with increasing high priority load, with no penalty in SP class performance at low to medium network loads. 相似文献
976.
Multi-Code Direct-Sequence Code-Division-Multiple-Access (MC-CDMA) has been proposed as a flexible multiple access scheme for wireless packet networks that support a large variety of mobiles with different and even time-varying rates. Using MC-CDMA, traffic streams with significantly different transmission rates can be easily integrated into a unified architecture, with all the transmissions occupying the same bandwidth and having the same spread spectrum processing gain. In this paper, we address medium-access and interference issues in MC-CDMA wireless packet networks. For medium access, we propose and study Multi-Code CDMA (MC-CDMA) with Distributed-Queueing Request Update Multiple Access (DQRUMA) to form a unified bandwidth-on-demand fair-sharing platform for multi-rate wireless services. DQRUMA is an efficient demand-assignment multiple access protocol for wireless access and scheduling. Pseudo-Noise (PN) codes (primary codes) and optimal power levels are allocated to the mobiles on a slot-by-slot basis, and a Maximum Capacity Power Allocation (MCPA) criterion exploits the sub-code concatenation property of the MC-CDMA transmission. Simulation results show that the system provides close to ideal-access performance for multi-rate mobiles, both with homogeneous traffic characteristics and with a mix of heterogeneous traffic characteristics. Finally, we analyze the effects of MC-CDMA intercell interference on the reverse link (i.e., mobile to cell site) and investigate interference reduction by using the Maximum Capacity Power Allocation (MCPA) criterion. Our results show significant reduction in reverse-link MC-CDMA intercell interference is possible using the MCPA criterion. 相似文献
977.
Mark R. Mujwahuzi 《国际水资源开发杂志》1984,2(1):75-83
The rationale behind the decision to invest in the development of rural water supply in Tanzania is discussed. It is shown that theoretically economic as well as social benefits are supposed to influence investment decisions. In practice, however, choice of projects to be developed are made solely on the basis of social rather than economic factors. Economic potential of such projects are generally not considered. Examples of small scale irrigation, fish farming and village afforestation are discussed. It is concluded that economic potential of rural water supply projects should be considered together with the social benefits during the planning stages of such projects. 相似文献
978.
Batch bioassays have been conducted to characterize the response of methanogenic bacteria to several constituents of sulfite evaporator condensate. The results can be grouped into three ranges with increasingly severe consequences to anaerobic reactors: a low concentration, no effect range; a medium concentration range where methanogenesis is temporarily interrupted or slowed down, but may return to normal; and a high concentration range where methanogenesis is permanently inhibited. In some cases the toxicant was metabolized when present in the lower concentration ranges. There was also evidence that mechanisms other than fermentation to methane were significant in accounting for removal of the toxicants from solution. Organisms acclimated to low concentrations of a toxicant are better able to withstand a shock load of that toxicant than are unacclimated organisms. 相似文献
979.
Continuum based integrated circuit process modeling is the dominant tool used to investigate and understand integrated circuit (IC) development. This paper describes the commonly used models for implantation, diffusion, and material growth. In addition, the supporting numerical techniques are described. This paper focuses on the implementation in object oriented code, Florida Object Oriented Process Simulator (FLOOPS). The software architecture is described for implementing models and numerics. A number of process examples are introduced and discussed. 相似文献
980.
Furey-Kurkjian Maura L.; Pietrini Pietro; Graff-Radford Neill R.; Alexander Gene E.; Freo Ulderico; Szczepanik Joanna; Schapiro Mark B. 《Canadian Metallurgical Quarterly》1996,10(2):294
A subgroup of patients with probable Alzheimer disease (AD) reported a history of isolated visual disturbances (VS) early in the course of disease, without the characteristic memory complaints. Brain imaging and neuropathologic studies indicated that this subgroup had larger involvement of visual cortical areas and relative sparing of temporal. frontal, and limbic structures compared with classic AD. Consistent with these findings, the authors hypothesized that the cognitive deficits in this subgroup would be distinctly different from those seen in more typical AD patients. The authors studied 10 probable AD patients with VS (AD&±&|S), 22 patients without VS (AD–), and 25 healthy controls with a neuropsychological test battery. Compared with AD–, AD&±&|S patients performed significantly better on tests of verbal memory and had greater impairment on tests of visuospatial skills, suggesting a distinct pattern of cognitive dysfunction consistent with metabolic and neuropathologic reports. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献