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81.
功率放大器的栅极偏置电压控制一直是功放设计者需要考虑的问题。本文介绍了数字动态偏置控制芯片IA4910在功放中的应用。它既降低了与实现偏置功能相关的总体成本,同时又提高了LDMOS器件的温度补偿性能。 相似文献
82.
83.
In the present study, the authors examined somatosensory processing in 30 biological relatives of persons with schizophrenia (hereafter called "schizophrenia relatives"), 30 biological relatives of persons with bipolar affective disorder (psychiatric family control subjects), and 30 healthy control subjects with no family history of psychopathology. All 3 groups completed a weight discrimination task, a 2-point discrimination task, and a complex cognitive somatosensory task (i.e., graphesthesia). The schizophrenia relatives performed significantly worse on all 3 somatosensory tasks compared with both the healthy control subjects and the bipolar relatives. The healthy control subjects and psychiatric family control subjects showed no significant differences on any of the somatosensory tasks. Within the weight discrimination and 2-point discrimination tasks, schizophrenia relatives showed group differences on the d' index, the measure of sensitivity, whereas all 3 groups did not differ on lnβ, the measure of response bias, suggesting a genuine difference in weight and touch sensitivity. The d' value of the weight discrimination task was significantly associated with both the cognitive-perceptual factor and negative symptom factor of the clinical questionnaire (e.g., Schizotypal Personality Questionnaire; SPQ), whereas the 2-point discrimination d' value and graphesthesia scores were significantly associated only with the cognitive-perceptual factor of the SPQ. Implications for the possible relation between somatosensory task performance and schizophrenia liability are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Joormann Jutta; Hertel Paula T.; Brozovich Faith; Gotlib Ian H. 《Canadian Metallurgical Quarterly》2005,114(4):640
The authors examined intentional forgetting of negative material in depression. Participants were instructed to not think about emotional nouns that they had learned to associate with a neutral cue word. The authors provided participants with multiple occasions to suppress the unwanted words. Overall, depressed participants successfully forgot negative words. Moreover, the authors obtained a clear practice effect. However, forgetting came at a cost: Compared with the nondepressed participants and with the depressed participants who were instructed to forget positive words, depressed participants who were instructed to forget negative words showed significantly worse recall of the baseline words. These results indicate that training depressed individuals in intentional forgetting could prove to be an effective strategy to counteract automatic ruminative tendencies and mood-congruent biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Media bias was investigated through the effects of a TV interviewer's preferential behavior on the image of the interviewee in the eyes of the viewers. Judges viewed a political interview with either a friendly or a hostile interviewer then rated their impressions of the interviewed politician, whose behavior was identical in all conditions. The preferential nonverbal behavior of the interviewer (controlling for recognition and comprehension of verbal content) systematically influenced viewers' ratings of the politician. The effect consisted mainly of damage to the politician in the hostile interviewer condition. Describing the interviewee as a professor yielded a similar preferential behavior effect. A strong halo effect was identified, but it was ruled out as the mechanism accounting for the interviewer effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
M. Dolores Jiménez-Gamero Juan Luis Moreno-Rebollo Juan M. Muñoz-Pichardo Ana M. Muñoz-Reyes 《TEST》2005,14(2):515-542
One of the areas of Statistics in which the influence analysis has been widely studied is the multiple linear regression model.
Nevertheless, the influence diagnostics proposed in this context cannot be applied to regression in complex survey, under
randomized inference, since the i.i.d. case does not incorporate any probability weighting or population structure, such as
clustering, stratification or measures of size into the analysis.
In this paper we introduce some influence diagnostics in regression in complex survey. They are built on the conditional bias
concept (Moreno-Rebollo et al., 1999). We emphasize the similarities and differences of the proposed measures with respect
to the existing ones for the i.i.d. case.
Research partly supported by the Spanish MCYT grant BFM2001-3844 and Spanish MEC grant MTM2004-0111433. 相似文献
87.
K. F. Eid O. Maksimov M. B. Stone P. Schiffer N. Samarth 《Journal of Superconductivity and Novel Magnetism》2005,18(3):421-426
We discuss the annealing-dependence of exchange bias in Ga1−
x
Mn
x
As epilayers that are overgrown with Mn. Although pure Mn is a known antiferromagnet, we find that the as-grown Mn overlayer
does not produce any exchange coupling with Ga1−
x
Mn
x
As. Rather, our studies indicate that annealing in air is essential for creating the standard signatures of exchange bias
(a clear shift in the magnetization hysteresis loop and an increased coercive field). We use X-ray photoelectron spectroscopy
to characterize the compositional depth profile of both as-grown and rapid thermal annealed samples. These studies demonstrate
that the cleanest exchange bias arises when the Mn overlayer is completely converted into MnO. 相似文献
88.
有始无终信号的卷积在用数值计算方法来计算时会带来误差 ,包括截尾误差、近似误差和字长舍入误差 ,其中截尾误差往往较大。适当选取信号的长度 ,可以在相应时间段内消除截尾误差 相似文献
89.
偏磁式消弧线圈的新型调谐原理 总被引:4,自引:0,他引:4
偏磁式消弧线圈的现有调谐方法,在电网极度平衡地区,电容电流检测精度受到限制。本文提出采用注入法的偏磁式消弧线圈的新型调谐方法,并进行系统设计,研发出基于双机通讯式的采用注入法的偏磁式消弧线圈控制器样机。试验结果表明,新型原理正确,满足现场应用要求。 相似文献
90.
研究了贝叶斯频谱估计的基本理论和基本方法 ,分别对无噪声和有噪声的简谐正弦信号进行了频谱估计。计算结果显示 :无噪声信号频率估计偏倚为零 ;当信号噪声系数S/N =1时 ,贝叶斯频率估计的偏倚与Jaynes的理论值一致 相似文献