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31.
DCS在采暖锅炉房中的应用   总被引:2,自引:1,他引:1  
介绍了Jx—300X DCS系统的组成、功能、特点以及热水锅炉主要控制方案及其在锅炉测控方面的应用。  相似文献   
32.
压缩奇偶相干态的熵压缩特性   总被引:3,自引:1,他引:2  
李永平  夏云杰 《光电子.激光》2003,14(11):1210-1214
用数值方法讨论了相干态强度、相位角和压缩参数对压缩奇偶相干态位置熵和动量熵压缩特性的影响。结果表明,压缩奇偶相干态的位置熵和动量熵均可呈现压缩性,压缩偶相干态的最大熵压缩度比压缩奇相干态的要大。熵压缩度与相干态强度、相位角和压缩参数均有关系,但压缩因子对场熵压缩的影响最大。当其它条件一定时,压缩偶相干态在压缩参数|β|=O.95时,位置熵(或动量熵)的压缩度最大,但压缩奇相干态无此特点。  相似文献   
33.
The modality effect in immediate recall refers to superior recall of the last few items within lists presented in spoken as opposed to printed form. The locus of this well-known effect has been unclear. N. Cowan, J. S. Saults, E. M. Elliott, and M. Moreno (2002) introduced a new method to distinguish between the effects of input serial position, output serial position, and the number of items yet to be recalled and found that large modality effects occurred only in conditions in which delay and interference at output (from items already recalled) was high. The authors replicated that finding, even when the response period included output interference acoustically similar to the spoken stimuli to be recalled. However, the authors found that output delay and interference act only by lowering the level of performance to a more sensitive range. The modality effect thus originates during encoding of the list to be recalled, not during output. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
DGPS在可控震源施工中的应用   总被引:1,自引:1,他引:0  
吴俊松 《物探装备》2003,13(2):81-83,126
在可控震源施工中,采用DGPS(差分全球卫星定位系统)实施实时点位监控,对保证施工质量、提高生产效率起着积极的作用。本文主要介绍PELTON ADVANCE Ⅲ GPS系统的安装和使用情况。  相似文献   
35.
Social dominance orientation (SDO) has been proposed as an important variable in the explanation of prejudice. We distinguish between three conceptualizations of SDO: SDO as a personality trait (personality model), SDO as a moderator of the effects of situational variables (Person X Situation model), and SDO as a mediator of the effect of social position on prejudice (group socialization model [GSM]). Four studies (N = 1,657) looking at the relations between social positions, SDO, and prejudice in a natural setting and in a laboratory setting provide strong support for the GSM. In contrast to previous correlational findings, there is evidence of a cause (dominant social position), an effect (prejudice increases), and a mediator (SDO). These results suggest new perspectives on the integration of individual and contextual determinants of prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
36.
目前各杂志所发表的关于凸轮测量的文章,所讨论的均是凸轮的顺序测量方法,有关凸轮的逆序测量(反求工程)方法,尚未见于文字。本文将对凸轮的逆序测量方法进行探讨。  相似文献   
37.
Five monkeys (Macaca mulatta) were trained on 2 sets of 3 5-item serially ordered lists. Then, each set was either linked or not in a counterbalanced, within-subject design. Linking entailed training on the 2 pairs that ordered the 3 5-item fists into a single overall 15-item series. Choices on novel pairings after linking conditions attempted to define the unique contributions of knowledge of within-list ordinal position and between-lists link training. With linkage, the series was immediately treated as a 15-item ordered list. Without linkage, choices reflected list positions from initial learning, but continued testing with directional reward yielded gradual ordering into a 15-itern list. Apparently, monkeys remembered and used initial list-position information, but linkage allowed inference of an integrated serial relationship among items. Results supported primate list memory as an organizational process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
38.
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy.  相似文献   
39.
40.
总结了治理谐波的一些基本方法,列出了变频器、UPS及各种家用电器的谐波实测数据,介绍了谐波治理方案确定的步骤:首先对谐波源设备进行评估,初步确定参数或实际测量谐波值。然后根据谐波源设备分布的情况确定补偿位置、容量及相关参数,最终选定较完整的补偿方案。较详细地介绍了:①补偿位置的确定原则;②补偿容量确定的两种方法:估算法和计算法;③有源滤波器的三相三线或三相四线的确定和性能比较;④有源滤波器的主要技术参数及与无源滤波器的比较;⑤串行通信问题。  相似文献   
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