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191.
This essay describes the domain of research in communication law and policy. It is based on a content analysis of research published in the journal Communication Law and Policy (1996–2004), papers presented to the Communication Law and Policy Division at annual conferences of the International Communication Association (1997–2004), as well as consideration of other resources. The most frequent areas for research were media regulation, Internet policy, and freedom of expression issues. After reviewing recent literature on the first two topics, we identified and showcased two emergent categories deserving future attention: communication and the law (particularly fair trial-free press issues) and implications of the burgeoning consolidation of media ownership.  相似文献   
192.
Master sintering curve concepts as applied to the sintering of molybdenum   总被引:6,自引:0,他引:6  
Sintering experiments with various molybdenum powders are rationalized using a master sintering curve concept that collapses density, grain size, or other parameters onto a single curve. In this case, the integral work of sintering is developed and customized for different green densities. Construction of the master sintering curve is described to show how the curve can be normalized with respect to green density effects. Various grades of molybdenum for metal injection molding and die compaction are included in the analysis, processed over a range of heating cycles. Die-compacted samples of varying green densities are used to illustrate the efficacy of the new, normalized master sintering curve concept. Sintering cycle optimization is one possible outcome from this analysis.  相似文献   
193.
This paper represents a portion of the evaluation of the use of Statistical Process Control within the realm of Conventional Computer Process Control. Various control charts commonly utilized in continuous processes are evaluated when subjected to process disturbances typical of continuous processes. The control charts considered are the Moving Average and Moving Range Chart combination, the Individual and Moving Range Chart combination, and the Exponentially Weighted moving Average Chart. The types of process disturbances considered are unit step and linear trend disturbances to the process average. The evaluation is based on the determination of the Average Run Lengths (ARLs) resulting from computer simulations.  相似文献   
194.
Forty-three lines of barley, including ancestral (wild), landraces, Middle Eastern lines, and modern cultivars, were grown under two different sets of environmental conditions. Hordenine production in barley roots was determined at the one-leaf stage by HPLC analysis and, in two lines only, over a period of 35 days. Forty-two of the 43 lines produced significant amounts of hordenine, although there was no variation among groups. Middle Eastern lines had the highest production with 327 µg/g on a dry weight basis. Production was, however, determined more by environmental conditions during growth than by genetic factors. Hordenine production was up to seven times higher in plants grown under lower light intensities.  相似文献   
195.
Conducted 2 laboratory experiments with 117 undergraduates to examine (1) the effect of assigned goal difficulty on arousal (self-report and heart rate), cognition (perceived norm, self-efficacy strength, and personal goal), and behavioral (task performance) measures and (2) the role of heart rate as a mediator of the goal-difficulty–performance relation. All Ss performed a task requiring cognitive and physical responses. Results of both experiments demonstrate that assigned goal difficulty affected heart rate, cognition, and task performance and that heart rate change was positively related to the cognitive and behavioral measures. Regression analyses suggested that a cognitive–affective mechanism may mediate the goal-difficulty–performance relation. Discussion is focused on the theoretical and practical implications of integrating an arousal concept within goal-setting theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
196.
197.
3G及后3G时代     
JohnLipp 《移动通信》2003,27(8):105-107
1 引言 目前,3G标准已制定完备,频谱也可用,牌照已授予,基础设施也准备就绪。当日本和英国等市场的首批运营商推出3G网络时,全世界都在期待着3G之后的新技术。亚洲在决定这一新领域的过程中起着领导作用。这是因为:首先,亚洲运营商获得3G许可证的成本相对较少,因此他们的资产负债表仍处于良好状态。其次,亚洲融合了不同标准,亚洲市场有很多竞争的3G技术,不  相似文献   
198.
199.
Abstract. Historians of science have labeled followers of the 18th cosmologist John Hutchinson (1674– 1737) as anti‐Newtonian. While Hutchinson was clearly anti‐Newtonian, this was not the case with later followers like George Horne and William Jones. Horne and Jones sought a rapprochement between Newton and Hutchinson; in their hands, interpretations of Newton's works were refashioned to support Hutchinson's biblically based cosmos and Trinitarian natural philosophy. Newton's thought could be used by conservative Anglican Churchmen to battle religious heterodoxy. This raises problems for traditional Enlightenment historiography which views Newtonianism as a set of ideas which supported and reinforced emerging modern forms of political and religious thought.  相似文献   
200.
Five individuals participated in an extensive practice study (10 1-hr sessions, 11,000 trials total) on a self-paced identity-judgment n-back task (n ranging from 1 to 5). Within Session 1, response time increased abruptly by about 300 ms in passing from n = 1 to n > 1, suggesting that the focus of attention can accommodate only a single item (H. Caravan, 1998; B. McElree, 2001). Within Session 10, response time was dramatically reduced and increased linearly with n for n ≤ 4, with a slope of about 30 ms. The data suggest that working memory consists of a focus of attention governed by a limited-capacity search, expandable through practice, and a content-addressable region outside the focus of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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