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91.
Rick Nelson 《电子设计技术》2008,8(9):32-32
高效的设计与测试策略需要整个芯片设计和生产生态系统全面努力。
设计和测试部门是否正趋向于融合?在阅读最近一些新闻报道时,您可能会产生这一想法。我曾在一篇早期的评论中提到过设计与测试的关系的问题(参考文献1)。该评论是对此前执行编辑Ron Wilson发表的一篇文章所做的回应(参考文献2)。我坚持自己在今年3月20日发表的文章中得出的结论,即“认为嵌入式仪器会将外置仪器淘汰的想法是错误的”。但是近期的新闻和事件均表明:嵌入式仪器将继续侵入市场。 相似文献
92.
Students with high scores (top third) on the essay portion of an Advanced Placement examination and low scores (bottom third) on the multiple-choice portion of the examination were compared with students with the opposite pattern (top third on the multiple-choice questions and bottom third on the essay questions). Across examinations in different subject areas (history, English, and biology), students who were relatively strong in the essay format and weak in the multiple-choice format were as successful in their college courses as students with the opposite pattern, especially in those courses where grades are typically not determined by multiple-choice tests. Although differential essay and multiple-choice test performance was not related to course grades, it was related to performance on other tests. Students in the high multiple-choice/low essay group performed much better than the other group on other multiple-choice tests, especially the verbal section of the SAT. In relation to their performance on multiple-choice tests, students in the high essay/low multiple-choice group performed well on other essay tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
94.
SB Hanauer EL Krawitt M Robinson GG Rick MA Safdi 《Canadian Metallurgical Quarterly》1993,88(9):1343-1351
Current long-term treatment of Crohn's disease is unsatisfactory. Based on the Crohn's Disease Activity Index (CDAI), this multicenter trial enrolled patients with either active Crohn's disease (CDAI > or = 150) or disease in remission (CDAI < 150). The primary measure of therapeutic response was mean change in CDAI from baseline to final visit. All patients began treatment with a dosage of < or = 4 g/day of mesalamine that ranged from 3.7 g at baseline to 3.4 g at final visit. Overall, 467 patients were enrolled: 333 (active disease) and 134 (remission). The median study participation time was 14 months. For patients entering with active disease, the mean reduction in CDAI was 77 points, with 42% (122/289) achieving remission by their final visit. For patients entering in remission, there was an increase in mean CDAI from 90 at baseline to 96 at final visit, with 79% (95/120) of patients in remission at final visit and 72% (31/43) in remission continuously after 12 months of therapy. From baseline to final visit, the mean prednisone dose decreased 5 mg/day in patients with active disease and 11 mg/day in patients in remission. Mesalamine was well tolerated and no adverse laboratory trends were observed. These results suggest that controlled-release mesalamine shows promise as a steroid-sparing agent and as a safe and effective long-term therapy for the induction of and maintenance of remission of mild-to-moderate Crohn's disease. 相似文献
95.
Meece Judith L.; Blumenfeld Phyllis C.; Hoyle Rick H. 《Canadian Metallurgical Quarterly》1988,80(4):514
We used structural equation analysis to test the validity of a goal mediational model for conceptualizing the influence of individual and situational variables on students' cognitive engagement in science activities. Fifth- and sixth-grade students (N?=?275) from 10 classrooms completed a set of questionnaires designed to assess their goal orientations and their use of high-level or effort-minimizing learning strategies while completing six different science activities. Results indicate that students who placed greater emphasis on task-mastery goals reported more active cognitive engagement. In contrast, students oriented toward gaining social recognition, pleasing the teacher, or avoiding work reported a lower level of cognitive engagement. The relative strength of these goals was related to differences in students' intrinsic motivation and attitudes toward science. Our analyses also suggested that these variables exerted a greater influence in small-group than in whole-class activities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
We measured the concentrations of extractable bioactive compounds in heartwood of live yellow-cedar (Chamaecyparis nootkatensis) trees and five classes of standing snags (1–5, averaging 4, 14, 26, 51, and 81 years-since-death, respectively) to determine
how the concentrations changed in the slowly deteriorating snags. Three individuals from each of these six condition classes
were sampled at four sites spanning a 260-km distance across southeast Alaska, and the influence of geographic location on
heartwood chemistry was evaluated. Cores of heartwood were collected at breast height and cut into consecutive 5-cm segments
starting at the pith. Each segment was extracted with ethyl acetate and analyzed by gas chromatography. Concentrations of
carvacrol, nootkatene, nootkatol, nootkatone, nootkatin, and total extractives (a sum of 16 compounds) for the inner (0–5 cm
from pith), middle (5–10 cm from pith), and surface (outer 1.1–6.0 cm of heartwood) segments from each core were compared
within each tree condition class and within segments across condition classes. Heartwood of class 1 and 2 snags had the same
chemical composition as live trees. The first concentration changes begin to appear in class 3 snags, which coincides with
greater heartwood exposure to the external environment as decaying sapwood sloughs away, after losing the protective outer
bark. Within core segments, the concentrations of all compounds, except nootkatene, decrease between snag classes 2 and 5,
resulting in the heartwood of class 5 snags having the lowest quantities of bioactive compounds, although not different from
the amounts in class 4 snags. This decline in chemical defense is consistent with heartwood of class 5 snags being less decay-resistant
than heartwood of live trees, as observed by others. The unique heartwood chemistry of yellow cedar and the slow way it is
altered after death allow dead trees to remain standing for up to a century with a profound impact on the ecology of forests
in southeast Alaska where these trees are in decline. 相似文献
97.
Kunick C Zeng Z Gussio R Zaharevitz D Leost M Totzke F Schächtele C Kubbutat MH Meijer L Lemcke T 《Chembiochem : a European journal of chemical biology》2005,6(3):541-549
In order to perform computer-aided design of novel alsterpaullone derivatives, the vicinity of the entrance to the ATP-binding site was scanned for areas that could be useful as anchoring points for additional protein-ligand interactions. Based on the alignment of alsterpaullone in a CDK1/cyclin B homology model, substituents were attached to the 2-position of the parent scaffold to enable contacts within the identified areas. Synthesis of the designed structures revealed three derivatives (3-5) with kinase-inhibitory activity similar to alsterpaullone. The novel 2-cyanoethylalsterpaullone (7) proved to be the most potent paullone described so far, exhibiting inhibitory concentrations for CDK1/ cyclin B and GSK-3beta in the picomolar range. 相似文献
98.
Rick Nelson 《电子设计技术》2009,(3):60-60,62,64-65
今天,忙碌穿梭的消费者也许觉得随身携带的不过是一台手机,而实际上,他们正带着七个以上射频,用于处理多频段蜂窝工作、Wi—Fi网络、蓝牙连接、辅助GPS(全球定位系统)等等功能。今后,他们还会拥有实现Adhoc式设备间通信的射频, 相似文献
99.
Rick Nelson 《电子设计技术》2008,15(11):46-46
手机市场有巨大的潜力。高通公司首席运营官兼高通CDMA技术总裁sanjay K Jha在今年6月11日的设计自动化研讨会的主题演讲中称,今天的无线用户有20亿,而到2020年,将有90亿人成为潜在的客户(摩托罗拉后来雇用Jha为协作首席执行官)。Jha也指出了这个爆炸性市场的一个缺陷:90亿潜在用户中,很多人在手机上的花费不超过15美元或20美元。 相似文献
100.
Rick Nelson 《电子设计技术》2008,15(12):90-92,94,96
模拟仿真器与设计捕捉工具在EDA市场已有长久的历史,这个市场一直在为数字仿真器增加某些Spice。不过,当仿真结果要转换为正弦波和硅片时,模拟EDA工具就会远远落后于数字EDA工具的水平。这种情况正在开始改变,传统数字EDA供应商正在出现以纳米尺度数字工艺支持模拟功能晶圆制作的工具。另外,代工厂专用工具包也正在简化用模拟工艺实现模拟、RF大电压功能的过程。 相似文献