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1.
This is a short history of the Smithsonian Microbeam Standards; their sources, selection, preparation, and analyses. Fifty-eight minerals, natural glasses, and synthetic samples have been characterized in the past 25 years. During that time, over 750 requests were received for approximately 11 000 individual samples. These reference samples are referred to as the Smithsonian Microbeam Standards.  相似文献   
2.
Engineering designers, who decide the physical shape and technical features of the built world, tend to forget that their predecessors have been making design decisions for hundreds of years. This paper gives several historical examples of design experience which can supply useful insights today, because the essential nature of engineering has not changed.Adapted from: Eugene S. Ferguson,Engineering and the Mind's Eye. Cambridge, Massachusetts: MIT Press, 1992  相似文献   
3.
Problem-prone behaviors of White American, Mexican American, and American Indian high school dropouts, students in good academic standing, and students in poor academic standing were surveyed. Generally, dropouts were most involved with drugs, perpetration of violence, and victimization by violence, students in poor standing were the next most involved, and students in good standing were least involved. Ethnicity did not interact with academic status, suggesting that differences between dropouts and students were similar across ethnic groups. Some ethnicity and gender main effects were found. Findings were related to R. Jessor's (see record 1992-23064-001) theory of problem-prone behaviors, to peer cluster theory, and to intervention design. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
Inductive social skills training (ISST), skill assembly social skills training (SASST), and cognitive relaxation coping skills (CRCS) training were compared with a no-treatment control condition for general anger reduction. At 4-wk follow-up, compared with the control group, all treatment groups showed equivalent reductions of the amount of anger experienced in a wide range of situations. ISST and CRCS Ss reported less anger in their worst ongoing provocation than did control Ss, whereas SASST Ss did not differ from Ss of other groups. Treatment groups enhanced anger control equally relative to the control group, but only the CRCS group significantly lowered outward, negative expression of anger, and only the ISST group reduced anger suppression, although active treatment groups did not differ from one another on these measures. The ISST group lowered day-to-day anger more than other groups. No treatment effects were found for nontargeted trait anxiety and assertiveness. Results are discussed in terms of prior findings and the efficacy and flexibility of ISST. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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6.
This potential for ion-pairing between dyclonine, a local anesthetic, and pharmaceutical dyes commonly used in liquid pharmaceutical formulations was examined. Occurrence of ion-pairing at a pH of 3 was confirmed by shift of the absorption maximum of all five sulfonate-containing dyes, and by measurements of octanol/water partition coefficient and surface tension. There was also an increase in the uptake of dyclonine by phosphatidylcholine liposomes in the presence of a dye (tartrazine) at pH 3 but not at pH 7, where the uncharged anesthetic is dominant.  相似文献   
7.
Within a clinical demonstration program, 59 traumatically brain-injured patients were treated with 1 of 3 mixes of treatment. Mix 1 included cognitive remediation (CGR), small-group interpersonal (SGI) communication training, therapeutic community activities, and personal counseling. Mix 2 was similar to Mix 1 but stressed SGI exercises and eliminated CGR. Mix 3 emphasized CGR and eliminated SGI exercises. The efficacy of the treatment mixes was evaluated with performance on neuropsychological tests, improved independence in functional activities, measures of intra- and interpersonal functioning, and vocational outcome. Ss' participation in the program, irrespective of treatment mix, yielded improvements in (1) self-image, (2) quality of interpersonal relatedness and interaction, (3) involvement with others in naturalistic settings, and (4) vocational outcome. Overall, data point to the superiority of the balanced mix (Mix 1) over Mixes 2 and 3. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
The authors examined whether expert testimony serves an educational or a persuasive function. Participants watched a simulated sexual abuse trial in which the child witness had been prepared for her testimony (i.e., she was calm, composed, and confident) or unprepared (i.e., emotional, confused, and uncertain). The trial contained different levels of expert testimony: none, standard (i.e., a summary of the research), repetitive (i.e., standard testimony plus a 2nd summary of the research), or concrete (i.e., standard testimony plus a hypothetical scenario linking the research to the case facts) testimony. Repetitive testimony bolstered the child's testimony, whereas concrete and standard testimony did not. Concrete testimony sensitized jurors to behavioral correlates of sexual victimization; standard and repetitive testimony desensitized jurors to these correlates. Implications for the use of procedural innovations in sexual abuse trials are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The main preoccupations of research in computer-aided geometric design have been on shape-specification techniques for polynomial curves and surfaces, and on the continuity between segments or patches. When modelling with such techniques, curves and surfaces can be compressed or expanded arbitrarily. There has been relatively little work on interacting with direct spatial properties of curves and surfaces, such as their arc length or surface area. As a first step, we derive families of parametric piecewise polynomial curves that satisfy various positional and tangential constraints together with arc-length constraints. We call these curves isometric curves. A space curve is defined as a sequence of polynomial curve segments, each of which is defined by the familiar Hermite or Bézier constraints for cubic polynomials; as well, each segment is constrained to have a specified arc length. We demonstrate that this class of curves is attractive and stable. We also describe the numerical techniques used that are sufficient for achieving real time interaction with these curves on low-end workstations.  相似文献   
10.
An optimal control approach to continuous-time aggregate production planning problems is presented. The proposed approach describes the production and capacity evolution (expansion, sell and deterioration) processes in the form of differential equations with regular production, subcontracting and capacity change rates controllable on one hierarchical level. In this way, the traditional disadvantages of the two-level problem consideration (one level for strategic capacity planning and the other for production smoothing) are avoided. Analytical properties for optimal production and capacity control regimes and conditions for their changeover are derived by the maximum principle. Based on these results, an insight into the optimal behaviour of the production system is gained and a fast numerical method is developed to identify and sequence the optimal regimes for arbitrary demand profiles. A computational example illustrates the effectiveness of the approach.  相似文献   
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