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41.
Scaling up visual programming languages 总被引:1,自引:0,他引:1
The directness, immediacy, and simplicity of visual programming languages are appealing. The question is, can VPLs be effectively applied to large scale programming problems while retaining these characteristics. In scaling up, the problem is how to expand applicability without sacrificing the goals of better logic expression and understanding. From a size standpoint, scaling up refers to the programmer's ability to apply VPLs in larger programs. Such programs range from those requiring several days' work by a single programmer to programs requiring months of work, large programming teams, and large data structures. From a problem domain standpoint, scaling up refers to suitability for many kinds of problems. These range from visual application domains-such as user interface design or scientific visualization-to general purpose programming in such diverse areas as financial planning, simulations, and real time applications with explicit timing requirements. To illustrate the scaling up problem, we discuss nine major subproblems and describe emerging solutions from existing VPL systems. First, we examine representation issues, including static representation, screen real estate, and documentation. Next, we examine programming language issues-procedural abstraction, interactive visual data abstraction, type checking, persistence, and efficiency. Finally, we look at issues beyond the coding process 相似文献
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BM Carlson 《Canadian Metallurgical Quarterly》1977,154(2):223-241
This research was designed to follow up the observation of Thornton and Kraemer ('51) that regressed, denervated limbs of Ambystoma larvae will not regenerate upon reinnervation if all digits on the limbs were not completely resorbed. The object of this experiment was to determine whether the presence of an apical structure, protruding past the amputation surface, would affect the regenerative process. Both forearms of adult newts were amputated midway between the elbow and the wrist. One limb served as a normal regeneration control, and in the other limb the third digit from the removed hand was implanted in place of the removed radius, so that the three distal phalangeal segments protruded past the plane of amputation. Blastema formation in the experimental limbs was delayed by several weeks as compared with control limbs. Approximately one third of the experimental limbs did not regenerate. The regenerates that did form were strongly deviated (45-90 degrees) radially from the longitudinal axis of the limb. Experimental analysis showed that the delay in regeneration is due largely to the projecting part of the digit. The radial deviation of the regenerates is not due to the digital implant, but rather to the removal of the radius. Trauma alone does not account for this phenomenon. 相似文献
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Presents the results of a study extending some of the variables of impression formation to a simulated employment interview setting. Life insurance agency managers evaluated 8 hypothetical job applicants 9 different times based on 9 different sets of information varying in favorability. 3 treatment conditions appear to have affected interviewers' evaluations: (a) valid test results (14%), (b) favorability of subjective personal history (12%), and (c) a combination of different types and amounts of information (11%). A primacy effect was found for unfavorable but not favorable information; unfavorable information had a recency effect when presented with favorable. Thus, the effect of subjective interview information in altering valid impressions is dependent on the amount, kind, and order in which it is presented. (30 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Children's and adults' recognition of spontaneous and posed emotional expressions in young children.
Felleman Elyse S.; Carlson Charles R.; Barden R. Christopher; Rosenberg Lois; Masters John C. 《Canadian Metallurgical Quarterly》1983,19(3):405
Investigated the degree to which 4–5 yr olds (n?=?48) can enact expressions of emotion recognizable by peers and adults; the study also examined whether accuracy of recognition was a function of age and whether the expression was posed or spontaneous. Adults (n?=?103) were much more accurate than children in recognizing neutral states, slightly more accurate in recognizing happiness and anger, and equally accurate in recognizing sadness. Children's spontaneous displays of happiness were more recognizable than posed displays, but for other emotions there was no difference between the recognizability of posed and spontaneous expressions. Children were highly accurate in identifying the facial expressions of happiness, sadness, and anger displayed by their peers. Sex and ethnicity of the child whose emotion was displayed interacted to influence only adults' recognizability of anger. Results are discussed in terms of the social learning and cognitive developmental factors influencing (a) adults' and children's decoding (recognition) of emotional expressions in young children and (b) encoding (posing) of emotional expressions by young children. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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William L. Carlson 《Accident; analysis and prevention》1979,11(2):137-153
Automobile crash injury was analyzed using data from the Crash Performance Injury Report (CPIR) for crashes which occurred since 1 January 1970 involving 1969 or newer cars, vans and pickup trucks. An injury prediction model was developed using delta V, vehicle weight, occupant age, seating position, crash configuration, and restraint usage to predict expected AIS. Expected AIS was then used to estimate the probability of death and severe injury. The model estimates were found to approximate the observed probability of death and severe injury from the National Crash Severity Study (NCSS) data file. 相似文献
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It has been more than four years since the last of my infrequent editorials in the International Journal of Stress Management (IJSM) and nearly a decade since my first (Carlson, 1998b). I am writing to you at this time first to inform you of a change in editorship, then to summarize a few high points of the past 10 years of IJSM as they relate to its management and future. My focus will be on matters dear to journal editors and useful to submitters and subscribers concerning submissions, content, and editorial activity, since such issues determine journal policy and direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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