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21.
The author presents the results of an experimental investigation into the comparative usefulness of textual tools and graphical tools for the program understanding phase of Cobol program maintenance. Both novice and experienced programmers are used as subjects. The results show a slight superiority for graphical tools when they are used by less experienced programmers. They cast doubt on the importance of rigid adherence to program design methodologies for experienced programmers and on the extensibility of experiments using relatively inexperienced student subjects 相似文献
22.
M. P. Sullivan and R. R. Reno (1999) (see record 1999-03790-003) provided evidence that group members can accurately assess the task-related performance of other group members, thus contributing to the small number of studies linking interpersonal perceptions to objective criteria. This evidence, along with Sullivan and Reno's finding that consensus does not exist for liking (i.e., liking is more a function of the relationship between target and perceiver rather than anything specific to either), may have important implications for theorists and clinicians alike. Unfortunately, Sullivan and Reno may have confounded the appropriate levels of analysis used to frame their questions and justify their conclusions. This comment explores the level-of-analysis issue and considers some group therapy implications of lack of consensus for likability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
Administered a mixed-modality (visual and auditory) continuous recognition task, followed immediately by a final recognition test, to 16 women in each of 3 age groups (18–23 yrs, 38–50 yrs, and 60–74 yrs). Ss gave recognition responses for both the words and their presentation modality. Although older Ss remembered less information about input mode than did the 2 younger groups, the age decrement was not the result of faster forgetting of such information by the elderly. When a ceiling effect at the initial lag was taken into account, forgetting rates for both words and input mode were comparable across the adult life span. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Numerous studies have shown that people underuse base-rate information in making social judgments and rely instead almost exclusively on individuating information. Seven studies reported here demonstrate that this occurred partly because most past studies gave Ss base-rate information before giving them individuating information. A recency effect in the use of base-rate and individuating information is demonstrated using a set of reasoning problems of varying character. The recency effect is shown to be the result of Ss' inferences (based on conversational conventions) that the experimenter believes that Ss should rely most on the piece of information presented last. Additional evidence discredits the hypothesis that the recency effect is due to heightened availability of more recently acquired information in memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
This paper presents a method of predicting the outer loop gain of dc-dc converters when there is a general (nonresistive) impedance as a load. Based on this prediction, it is possible to then derive a corresponding phase margin, gain margin and bandwidth in order to define a dc-dc converter's stable operating area. Two applications of the method are presented for performance prediction in: 1) dc-dc converters with additional capacitors placed across their load; 2) source converters in a distributed power system. In both applications, the theoretical predictions match closely to the experimental data. 相似文献
26.
Fourth-generation languages (4GLs) have been widely hailed as the “saviors” of data processing problems in the 1980s and in the future. They have also been condemned as limited in application. Relatively few studies examine the organizational use of such tools without presenting it as a case study of only one organization's experience. This article discusses the results of a survey of organizations using fourth-generation languages. 相似文献
27.
This paper presents an integrated magnetic isolated two-inductor boost converter. Patent pending: USPTO/Worldwide filing number 60/444821. All magnetic components are integrated into one magnetic assembly. Two inductor windings are intrinsically coupled to allow input current to increase only when both primary switches are closed. The operation principle, start-up, and protection mechanisms are detailed. A prototype converter has been built. Experimental and simulation results verify the analysis. 相似文献
28.
The in-plane molecular structures of octa-alkyl substituted copper phthalocyanine LB films deposited on graphite have been resolved with a scanning tunnelling microscope (STM). The face-to-face stacking of Pc macrocycles has been observed in the topographies of R8PcCu monolayers. The stacking period was found to be 3.8–4 Å and the molecular rows were separated by 19 Å and 16 A for (C6H13)PcCu and (C5H11)PcCu respectively. 相似文献
29.
Charles W. Roeder Eric J. LumpkinDawn E. Lehman 《Journal of Constructional Steel Research》2011,67(11):1760-1772
Concentrically braced frames (CBFs) are stiff, strong structures that are suitable for resisting large lateral loads. Special CBFs (SCBF) are used for seismic design and are designed and detailed to sustain relatively large inelastic deformations without significant deterioration in resistance. Current AISC Seismic Design Provisions aim to ensure the brace sustains the required inelastic action, but recent research showed that current SCBF design requirements lead to variable seismic performance, unintended failure modes, and limited deformation capacity. To improve the seismic response of SCBFs, a balanced design procedure was proposed. The premise of the design methodology is to balance the primary yield mechanism, brace buckling and yielding, with other, complementary ductile yielding mechanisms, such as gusset plate yielding. This balance process maximizes ductile yielding in the frame thereby maximizing the drift capacity of the frame. Further, the undesirable failure modes are balanced with the yield mechanisms and the preferred failure mode, brace fracture, to ensure that the frame fails in the desired manner. To achieve the objectives of the design methodology namely maximum drift capacity, and adherence to a desired yield and failure hierarchy, rational resistance checks and appropriate balance factors (β factors) are used to balance each yield mechanism and failure mode. These factors were developed, validated, and refined using the measured results from an extensive test program. An SCBF connection design example to illustrate the application of the balanced design method and to demonstrate differences from the current AISC design method is presented in an appendix. 相似文献
30.
Pancreas divisum patients make up a small but problematic portion of ERCP cases. Minor papilla cannulation techniques have been improved. Recurrent pancreatitis patients generally benefit from minor papilla therapy. Methods to select patients who are likely to respond to invasive therapy need refinement. Clinicians and endoscopists are strongly encouraged to be cautious and conservative with this patient group until stronger data indicate optimal management schemes. 相似文献