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51.
We assessed the effects of posted feedback and warning ticket programs on speeding and accidents in two cities. In Experiment 1, speeding feedback signs were effective even when 10 were used in Dartmouth, Nova Scotia, and reductions in speeding were associated with reductions in accidents. The effectiveness of the signs was correlated with the number of intersections and residences within 0.5 km beyond them, and the signs had no effect on untreated streets. In Experiment 2, posted feedback and a warning program reduced speeding and accidents on 14 streets in Haifa, Israel.  相似文献   
52.
比较传统与改良鼻内镜下鼻骨复位术两种手术方式,探讨改良鼻内镜下鼻骨复位术的可行性与优势所在。局部麻醉下分别采用传统与改良鼻内镜下鼻骨复位术对闭合性单纯鼻骨骨折及部分合并鼻中隔骨折的患者进行复位后,比较两种手术方式患者的复位效果、术中出血、术后不适及住院时间。改良鼻内镜下鼻骨复位术较传统鼻内镜下鼻骨复位具有麻醉效果好、鼻...  相似文献   
53.
The effects of subunit formation on adult listeners' ability to notice changes in a continuous spectral gradient of sound were studied. Results of this experiment support the idea that the auditory system processes information differently within a unit, and that this processing does not occur unless the perceptual system detects unit boundaries. In this experiment, silences were inserted into a continuously changing sound to cause the formation of short units. Listeners noticed the change earlier in conditions with silences inserted than in to conditions where the transition was either unbroken or broken by loud noise bursts. Results are discussed in terms of two processes, one that accentuates stimulus properties present at moments of onset and offset, and a second that uses onsets and offsets to signal the beginnings and ends of units and reduces the change perceived within units.  相似文献   
54.
Many studies have observed phonetic and phonological differences between function words and content words. However, as many of the most commonly cited function words are also very high in frequency, it is unclear whether these differences are the result of syntactic category or word frequency. This study attempts to determine whether syntactically defined function words are indeed phonologically and phonetically reduced or assimilated when word frequency is balanced. Three experiments were designed to distinguish the relative contributions of the factors of category and frequency on phonetic and phonological reduction and assimilation. Overall results suggest that syntactic category and word frequency interact with phonetic and phonological processes in a more complex way than previously believed. Experiment 1 measured final t/d dropping, a reduction process, using electropalatography (EPG). Experiment 2 examined vowel reduction using acoustic measures. In Experiment 3, palatalization, an assimilation process, was examined using EPG. Results showed that t/d dropping responds to the factor of syntactic category, whereas palatalization is affected by word frequency; vowel reduction responded to both factors, with a dominant syntactic category effect and a secondary within-category frequency effect. The implications of these findings for models of lexical representation and theories of language acquisition are discussed.  相似文献   
55.
A method is presented for calculating the amount of information conveyed to a hearer by a speaker emitting a sentence generated by a probabilistic grammar known to both parties. The method applies the work of Grenander (1967) to the intermediate states of a top-down parser. This allows the uncertainty about structural ambiguity to be calculated at each point in a sentence. Subtracting these values at successive points gives the information conveyed by a word in a sentence. Word-by-word information conveyed is calculated for several small probabilistic grammars, and it is suggested that the number of bits conveyed per word is a determinant of reading times and other measures of cognitive load.  相似文献   
56.
57.
Three experiments were conducted to assess the effects of the interspersing procedure on students' mathematics performance, perceptions of mathematics assignments, and preference for mathematics assignments when more work was added. In Experiment I, college students worked computation problems from two assignments. The control assignment contained 15 three-digit by two-digit problems (3 × 2) and the experimental assignments contained 18 3 × 2 problems and 6 additional interspersed one-digit by one-digit problems (1 × 1). Students then rated the assignments and chose one for homework. Results showed significantly more students preferred (i.e., chose it for homework) the experimental assignment with the additional target (i.e., 3 × 2) and interspersed problems. Furthermore, significantly more students rated this experiment as requiring less effort and being less difficult. Moreover, students' mathematics performance was not affected by the procedure. Experiment II strengthened the internal validity by showing that students did not prefer the experimental assignment because it contained more target problems. Experiment III showed that the interspersing procedure was not powerful enough to extend findings beyond the 20% level (i.e., 40 and 60% more conditions). Results showed how the interspersing procedure could be used to encourage students to choose to do more target computation tasks. Discussion focuses on the applied value of the interspersing procedure and plausible causal mechanisms that may account for current and past findings related to student choice and interspersing brief tasks.  相似文献   
58.
Non-reductive moral realism is the view that there are moral properties which cannot be reduced to natural properties. If moral properties exist, it is plausible that they strongly supervene on non-moral properties- more specifically, on mental, social, and biological properties. There may also be good reasons for thinking that moral properties are irreducible. However, strong supervenience and irreducibility seem incompatible. Strong supervenience entails that there is an enormous number of modal truths (specifically, truths about exactly which non-moral properties necessitate which moral properties); and all these modal truths must be explained. If these modal truths can all be explained, then it must be a fundamental truth about the essence of each moral property that the moral property is necessarily equivalent to some property that can be specified purely in mental, social and biological terms; and this fundamental truth appears to be a reduction of the moral property in question. The best way to resist this argument is by resorting to the claim that mental and social properties are not, strictly speaking, natural properties, but are instead properties that can only be analysed in partly normative terms. Acceptance of that claim is the price of non-reductive moral realism.  相似文献   
59.
A central component of a commonly used weight-loss procedure developed by Stuart (1967), which emphasizes situational engineering (SE), was compared to eating behavior control (EBC), a treatment employing reinforcement of changes in eating habits. A third treatment encouraged development of individuals' own applications of a model of self-control and attempted to provide effective feedback regarding progress toward weight-loss goals. This self-initiated treatment (SI) was designed to be less directive than many behavioral treatment packages and to be more realistic about the expectations of subjects and the actual eating habits of overweight and normalweight people. Following baseline, treatment lasted six weeks and followup lasted 16 weeks. While all treatments produced weight losses, EBC surpassed SE during treatment. SI losses during treatment did not differ from SE or EBC, but SI was the only group that lost weight throughout followup, indicating the possible utility of more subtle, less directive interventions than those that have often been associated with behavioral approaches. The results of SE question the applicability to clinical procedures of the external cue hypersensitivity theory of obesity (Schachter and Rodin, 1974), to which SE is closely related.  相似文献   
60.
A company-based lottery was used to reduce the number of nonessential miles employees drove their personal cars each day and thereby save gasoline. Employees were divided into an experimental and a contrast group. The experimental design involved two conditions: (a) a baseline in which no consequences were attached to driving behavior, and (b) a month-long lottery in which the experimentals were rewarded for decreasing their percentage of average miles driven per day relative to their initial baseline average. The experimentals received an ABA order of conditions while the contrast group remained in baseline. The lottery condition consisted of four weekly lotteries and one grand drawing held at the end of the month. During the lottery condition, the experimentals reduced their average daily mileage by 11.6% relative to their initial baseline (7.85 miles per employee per day) while the contrast employees increased their average mileage by 21.2%. Both groups exceeded their initial baseline averages in the return to baseline. The study was almost cost-effective because the experimentals' gas savings ($75) was within $4 of the cost of motivating them to reduce their mileage ($79).  相似文献   
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