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111.
112.
WFT-666是由磺甲基腐殖酸钾、有机硅聚合物、低分子阳离子有机化合物、苯酚、甲醛缩聚而成的一种新型阳离子低荧光防塌剂。本文介绍了WFT-666的合成及室内性能评定结果。WFT-666可抗盐至饱和盐水,抗钙和镁,耐200℃高温,荧光显示低。用该剂处理的钻井液性能稳定,流变参数合理,页岩回收率高,页岩相对膨胀率低,页岩稳定指数高,与其它处理剂的配伍性好。  相似文献   
113.
Consideration is given to the control problem in a linear stochastic differential system where constant noise intensities in equations of state and observation are prescribed only accurate within the membership of some known sets. For control optimization, an integral root-mean-square performance criterion is used. The problem is solved by the transition to a dual one, which makes it possible to prove the existence of a saddle point of the criterion and obtain an explicit expression for the minimax control operator as functions of the solution to the dual problem. To solve the latter, an iteration algorithm is proposed; the convergence of the algorithm is proved and investigated by a model example.  相似文献   
114.
Examined the effects of counselor note-taking behavior on participants' impressions of a counselor during a career counseling session. A total of 140 participants (70 men and 70 women) rated 1 of 2 videotapes designed to credibly simulate a real career counseling interview. Note-taking was the independent variable. Results of this study suggest that whether a counselor is observed in a note-taking or non-note-taking condition has no significant effect on perceived counselor expertness, attractiveness, or trustworthiness. However, there was a significantly greater willingness of the participants to see the counselor who refrained from note-taking. Results offer tentative suggestions for those counselors who choose to take notes during a career counseling session. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
115.
The present study is based on the hypothesis that patients with recurrent attacks of aphonia differ from those with non-recurring attacks of aphonia in their anxiety levels, social assertiveness and stress-coping strategies. A comparison was made between 21 women with recurring aphonia and 19 women with non-recurring aphonia with respect to these three factors. Seventeen healthy women served as volunteers. Compared to patients with non-recurring aphonias, patients with recurring aphonias exhibited a significantly higher level of anxiety and significantly more respect for social norms and codes of propriety. Their coping was also characterized by a higher escape tendency. Patients with recurring aphonias also reported a significantly higher number of problems in their private lives within the preceding 5-year period. In therapy patients should be encouraged to reflect upon a possible rigidity toward social norms and better understand fears regarding conflicts in personal relationships.  相似文献   
116.
Five wavelength multiplexed pulse streams are generated in an integrated 16×1 laser modulator array by sinusoidally driving five of the potential 16 electroabsorption modulators. At a repetition rate of 2.5 GHz, near transform-limited pulses spaced in wavelength over 7.6 nm are observed. Pseudorandom coding of one channel is achieved by applying an electrical RZ data signal to the modulator  相似文献   
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118.
Endocrine disorders in critically ill infants and children can be the manifestation of an existing but previously unrecognized condition, or hormonal derangements precipitated by deleterious effects on endocrine function of a critical illness or its prescribed therapy. To achieve successful resolution of these crises, a general understanding of various endocrine dysfunctions, clinical symptomatology, diagnosis, and medical and nursing management is essential.  相似文献   
119.
This paper studies the transient behavior of an adaptive near-far resistant receiver for direct-sequence (DS) code-division multiple-access (CDMA) known as the minimum mean-squared error (MMSE) receiver. This receiver structure is known to be near-far resistant and yet does not require the large amounts of side information that are typically required for other near-far resistant receivers. In fact, this receiver only requires code timing on the one desired signal. The MMSE receiver uses an adaptive filter which is operated in a manner similar to adaptive equalizers. Initially there is a training period where the filter locks onto the signal that is sending a known training sequence. After training, the system can then switch to a decision-directed mode and send actual data. This work examines the length of the training period needed as a function of the number of interfering users and the severity of the near-far problem. A standard least mean-square (LMS) algorithm is used to adapt the filter and so the trade-off between convergence and excess mean-squared error is studied. It is found that in almost all cases a step size near 1.0/(total input power) gives the best speed of convergence with a reasonable excess mean-squared error. Also, it is shown that the MMSE receiver can tolerate a 30-40 dB near-far problem without excessively long convergence time  相似文献   
120.
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