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1.
Developing competency-based methods for near-real-time air combat problem solving assessment 总被引:1,自引:0,他引:1
Air combat scenarios present unique problems where the solution is not obvious. An advanced networked simulation environment can be used to train high-level cognitive air combat skills such as problem solving. A problem in the development of principled and construct oriented assessment is related to determining the level of specificity of the assessment. We present a detailed discussion of the definition of critical competencies associated with combat mission problem solving performance, and we describe our approach to develop and implement an embedded performance assessment system that maps outcomes to these competencies. Finally, we discuss the implications for our approach for comprehensive assessment and discuss our goals for an evaluation of the competency-based approach to assessment. 相似文献
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An octene-modified linear low density polyethylene has been used to examine the mechanisms involved during thermal annealing. Annealing temperatures ranged from 60 to 100°C. Annealing results in crystallinity increments and these respond to two concurrent effects. One involves the segregation from crystalline regions of low molecular weight moieties in the polymer's molecular weight distribution; the other is lamellar thickening, leading to the formation of more highly perfected crystalline domains. In the present polymer, the two effects were found to be in balance at annealing temperatures near 80°C leading to the optimum distribution of crystalline regions in the amorphous portions of the polymer. The effect of thermal conditioning on mechanical properties of the polymer was illustrated in terms of the initial modulus and the polymer's yield strength. The twin mechanisms of molecular fractionation and lamellar thickening were found to influence both of the mechanical property parameters. 相似文献
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An uncommon systemic reaction mimicking sarcoidosis after ligament reconstruction is reported. Clinical and radiological outcome after surgical treatment led to the diagnosis of a a specific injury caused by the ligament reconstruction device. 相似文献
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Rats were trained to discriminate 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT, 0.1 mg/kg i.p.) or 5-methoxy-N,N-dimethyltryptamine (5-OMe-DMT, 1.25 mg/kg i.p.), a selective and nonselective 5-hydroxytryptamine1A (5-HT, serotonin) receptor agonist, respectively, from saline in a two-lever procedure. The selective 5-HT1A receptor agonist ipsapirone substituted completely for 8-OH-DPAT (ED50, 1.52 mg/kg) and 5-OMe-DMT substituted partially for 8-OH-DPAT, whereas 8-OH-DPAT (ED50, 0.07 mg/kg) and ipsapirone (ED50, 4.15 mg/kg) substituted completely for 5-OMe-DMT. These results suggest that the discriminative stimulus properties of both 8-OH-DPAT and 5-OMe-DMT are 5-HT1A receptor mediated, although 5-OMe-DMT may involve an additional interaction with other 5-HT receptor subtypes. 5-OMe-DMT substituted for 8-OH-DPAT after application in the lateral ventricle (ED50, 3.0 micrograms/rat) and the dorsal raphe nucleus (DRN, 1.1 micrograms/rat). After application in the DRN (ED50 range, 1.4-5.0 micrograms/rat) and the median raphe nucleus (2.3 micrograms/rat), and after bilateral application into the CA-4 region of the dorsal hippocampus (4.1 micrograms/rat), 8-OH-DPAT also produced responding on the 8-OH-DPAT lever. Ipsapirone also substituted for 8-OH-DPAT after application into the DRN and the hippocampus (ED50S, 38 and 62 micrograms/rat, respectively). The 5-HT1A mixed agonist-antagonist (1-(2-methoxyphenyl) 4-[4-(2-pthalimido)butyl]piperazine, i.p. NAN-190) attenuated the discriminative stimulus effects of 8-OH-DPAT injected i.p. (0.1 mg/kg), into the DRN (10 micrograms) or into the hippocampus (2 x 10 micrograms).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
AA Schreiber K Frei W Lichtensteiger M Schlumpf 《Canadian Metallurgical Quarterly》1993,38(3-4):265-272
Prenatal exposure to diazepam and other benzodiazepines (BDZ) has been found to result in a marked reduction of T-lymphocyte proliferation during postnatal development of rats. In search for pathogenic changes underlying this effect, we investigated the mitogen lipopolysaccharide (LPS) and concanavalin A (ConA) stimulated release of tumour necrosis factor (TNF)-alpha by mixed splenocytes of male offspring from Long Evans rats treated with 1.25 mg/kg per day diazepam from gestational day 14 to 20. In response to LPS, TNF-alpha release was found to be significantly lower in mixed splenocytes of two- and four-week-old treated than in control offspring. However, at eight weeks of age, prenatally diazepam-treated animals showed a significantly higher LPS-induced TNF-alpha release than control rats. Since monocytes/macrophages represent a major source of TNF-alpha, additional experiments were performed on purified spleen macrophages and lymphocytes stimulated with LPS. TNF-alpha release was only detectable in supernatants of adherent spleen macrophages and not in supernatants of lymphocytes. Thus, our data indicate that a disturbance in TNF-alpha release from macrophages is involved in the deficient immune response of prenatally diazepam-exposed rats. 相似文献
8.
JK Tong CA Hassig GR Schnitzler RE Kingston SL Schreiber 《Canadian Metallurgical Quarterly》1998,395(6705):917-921
9.
The corrosion properties of Plasma-Hot-Wire-Surfacing Part one: resistance of Nickel-base-alloy claddings against pitting and intergranular attack This paper describes measurements at claddings of nickel-based-alloys C 276, C 4 and C 22 on the St 52-3 steel substrat produced by Plasma-Hot-Wire-Surfacing (PHS). The correct heat control during the welding process is a crucial factor for the preparation of nearly precipitate-free claddings. For this reason it was necessary to optimize all the process data. The claddings itself as well as the rolled reference material (both of nearly the same chemical composition) were examined by means of metallografical and microanalytical techniques. Corrosion measurements show, that the composite materials exhibit high resistance both against pitting and intergranular corrosion and comparable to the properties of the rolled reference material. This was shown by determination of the critical pitting temperature in quinary salt solution, by electrochemical techniques in acidic chloride solution and by investigation in iron-(III)-sulfate-sulphuric acid solution. 相似文献
10.
Mechanical properties of high density polyethylene (HDPE) extended to draw ratios in the 20–40 range have been determined and compared with corresponding properties of the polymers containing particulates including rutile, carbon black, iron oxide, and mica. Shrinkage of drawn structures was studied to temperatures near the fusion of the polymer host. The degree of interaction at polymer/additive interfaces was varied by surface coating certain of the solids with standard coupling agents. Solids were found to increase tensile moduli and to decrease shrinkage, particularly at higher exposure temperatures. The magnitude of changes due to the presence of solids was shown to depend on the apparent interaction at contacts between host and additive. In a dispersion–force matrix, like HDPE, benefits were optimized when the particulates were amphoteric or neutral, rather than having pronounced acid or base interaction potentials. 相似文献