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61.
Field audits and experiments have found substantial error rates when students and professionals have built spreadsheet models. In this study, 102 undergraduate MIS majors and 50 MBA students developed a model from a word problem that was relatively simple and free of domain knowledge. Even so, 35% of their 152 models were incorrect. There was no significant difference in errors per model between undergraduates and MBAs. Even among the 17 MBAs with 250 h or more of experience, 24% of the models contained errors. The cell error rate (CER)—the percentage of cells with errors—was 2.0%. When 23 undergraduates attempted to audit their models through code inspection, only three with incorrect spreadsheets (15%) produced clean spreadsheets when they finished the audit. 相似文献
62.
Denniston James C.; Blaisdell Aaron P.; Miller Ralph R. 《Canadian Metallurgical Quarterly》2004,30(3):190
Two experiments with rats as subjects were conducted to investigate the associative structure of temporal control of conditioned inhibition through posttraining manipulation of the training excitor-unconditioned stimulus (US) temporal relationship. Experiment 1 found that following simultaneous Pavlovian inhibition training (i.e., A → US/XA-no US) in which a conditioned stimulus (CS A) was established as a delay excitor, maximal inhibition was observed on a summation test when CS X was compounded with a delay transfer CS. Furthermore, posttraining shifts in the A-US temporal relationship from delay to trace resulted in maximal inhibition of a trace transfer CS. Experiment 2 found complementary results to Experiment 1 with an A-US posttraining shift from serial to simultaneous. These results suggest that temporal control of inhibition is mediated by the training excitor-US temporal relationship. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Urushihara Kouji; Wheeler Daniel S.; Miller Ralph R. 《Canadian Metallurgical Quarterly》2004,30(4):283
Effects of outcome-alone pretraining and posttraining exposure were investigated in conditioned suppression experiments conducted within a sensory preconditioning preparation with rats. Experiment 1 found that interference by outcome postexposure was stronger than that by outcome preexposure, suggesting a recency effect. Experiment 2 found that after a long retention interval, outcome preexposure produced more interference than outcome postexposure, suggesting a shift from recency to primacy with increasing retention interval. Experiment 3 showed that presentation of a priming stimulus that had been embedded within the earlier phase of treatment also caused a shift from recency to primacy. These results suggest that, at least in a sensory preconditioning paradigm, retrievability of outcome-alone exposure memory is an important determinant of any outcome-alone exposure effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Andrea Linkmeyer Katharina Hofer Michael Rychlik Markus Herz Hans Hausladen Ralph Hückelhoven 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(3):489-499
Fusarium head blight (FHB) of small cereals is a disease of global importance with regard to economic losses and mycotoxin contamination harmful to human and animal health. In Germany, FHB is predominantly associated with wheat and F. graminearum is recognised as the major causal agent of the disease, but little is known about FHB of barley. Monitoring of the natural occurrence of FHB on Bavarian barley revealed differences for individual Fusarium spp. in incidence and severity of grain infection between years and between spring and winter barley. Parallel measurement of fungal DNA content in grain and mycotoxin content suggested the importance of F. graminearum in winter barley and of F. langsethiae in spring barley for FHB. The infection success of these two species was associated with certain weather conditions and barley flowering time. Inoculation experiments in the field revealed different effects of five Fusarium spp. on symptom formation, grain yield and mycotoxin production. A significant association between fungal infection of grain and mycotoxin content was observed following natural or artificial infection with the type B trichothecene producer F. culmorum, but not with the type A trichothecene-producing species F. langsethiae and F. sporotrichioides. Trichothecene type A toxin contamination also occurred in the absence of significant damage to grain and did not necessarily promote fungal colonisation. 相似文献
65.
This bibliometric study on the collaboration of Austria and six target countries (Slovenia, Hungary, Czech Republic, Denmark,
Switzerland and Israel) reveals the importance of differentiation between the bilateral and multilateral contingents in the
assessment of international scientific collaboration. For this purpose a “degree of bilaterality” (DB) and a “citation degree
of bilaterality” (CDB) are introduced. In our findings the DB and the CDB have values lower than 1/3 and 1/5, respectively.
Therefore, the total collaboration is mostly shaped in its volume and impact by the multilateral contingent. Regarding the
impact estimation of the collaboration publication output, a multi-faceted approach was used. It is recommended to separately
analyze the following three aspects: the un-cited range, the average range and the excellence range. Considering different
country specific parameters the total number of publications and citations were resized for each type of collaboration and
the results discussed. Only a very weak correlation between ‘times cited’ and the number of affiliations or authors was observed
at publication level. Neither the number of authors or affiliations determines impact increase. Rather internationalisation
and cooperation seem to be the crucial factors. 相似文献
66.
67.
Byron S. Villacorta Sarah Hulseman Andrew H. Cannon Ralph Hulseman Amod A. Ogale 《Polymer Engineering and Science》2014,54(9):2147-2154
The continuous extrusion of micro‐textured isotactic polypropylene (i‐PP) film and its tribological properties are reported. As analyzed by scanning electron microscopy, a rectangular‐semicircular micro‐patterned die successfully produced extruded cast‐films with hill‐like micro‐texture. Such films displayed static and kinetic coefficients of friction (COFs and COFk) values of 0.247 ± 0.028 and 0.245 ± 0.003, respectively, for a steel fixture sliding along the micro‐texture of the film. The equivalent COFs and COFk values for non‐textured (NT) films were 0.369 ± 0.036 and 0.340 ± 0.024, respectively, confirming that textured films displayed a reduction in COF of about 30%. For textured and NT films sliding on textured films, the COFk values were even lower at 0.161 ± 0.013 and 0.113 ± 0.004, which represents about 20–40% reduction as compared with that for the NT‐NT counterparts. Films coated with a silicone lubricant displayed COFs and COFk values of 0.334 ± 0.042 and 0.099 ± 0.012, respectively, for NT films sliding over lubricated NT films, and 0.426 ± 0.031 and 0.063 ± 0.006, respectively, for textured films sliding over lubricated textured films. The COFk values for textured/non‐lubricated films approach those of NT/lubricated films, indicating that micro‐textured polypropylene films may be used in environmentally sensitive applications where lubricants and fluorinated additives may not be used for reducing friction. POLYM. ENG. SCI., 54:2147–2154, 2014. © 2013 Society of Plastics Engineers 相似文献
68.
Computational Visual Media - We consider a face-to-face videoconferencing system that uses a Kinect camera at each end of the link for 3D modeling and an ordinary 2D display for output. The Kinect... 相似文献
69.
Color constancy from invariant wavelength ratios: An algorithm to simplify the chromatic adaptation model
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Ralph W. Pridmore 《Color research and application》2016,41(5):468-476
In a recent article on color constancy, the chromatic adaptation model was of a novel type comprising three components separately calculated—hue, chromaticness, and lightness. The constant hue component was a simple calculation of predicted wavelength but the other two components were less direct. This article provides an algorithm to simplify the model's calculation. Calculation is far simpler and more intuitive than conventional models using complex 3 × 3 matrix transforms with their various and contentious adaptation primaries and potential disadvantages (e.g., in brightness and color gamut). The model is shown to be at least as accurate as six other (conventional) models and does not require high math skill. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 468–476, 2016 相似文献
70.
The unceasing growth and divergence of the mobile landscape have led to the use of smartphone and tablet devices in consuming Web services (WS) in enterprises. However, in heterogeneous WS, the shift from the mobile client consumer approach to the mobile service hosting approach is insufficiently studied. With the advancement of storage and processing capabilities of these devices, coupled with the high availability of the Web, this research focuses on the use of the mobile devices as hosts of WS in a mHealth domain. In this paper, a cloud-centric middleware technique is employed to enable access to the mobile hosts. The paper presents mobile hosting of medical data which are modeled as light-weight WS which is deployed in a real-world system. Further, a workflow authorization model is proposed to ensure privacy and the prevention of unauthorized modification of data on the mobile hosts. A data encryption technique is also put forward to enforce security and privacy of the mobile hosted data. Our current implemented project, called SOPHRA, supports mobile communication over HTTP in a Wi-Fi environment. 相似文献