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151.
152.
Examined age and sex trends in emotional intensity in 432 Ss from adopting and nonadopting biological families. It was hypothesized that younger adults and females would report greater average levels of both positive and negative affect over time, as has been demonstrated in past research. 242 Ss (parents and offspring) completed a battery of mood scales. 190 Ss completed an affect intensity measure and a general behavior inventory. In support of the hypothesis, women scored higher on measures reflecting emotional intensity and manifestation of cyclothymic symptoms, and the scores on these measures decreased through the adult life span for both males and females. Potential reasons for the differences in emotional intensity are discussed. These include biological causes, cultural expectations, and current life experiences. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
153.
Effect of melt spinning on the microstructure and mechanical properties of three Ni-base superalloys
A microstructural and mechanical analysis was performed on three rapidly solidified nickel base superalloys. Transmission
and scanning electron microscopy along with tensile tests were performed on the ribbons in the as-cast and aged condition.
This investigation permitted a correlation to be made between cooling rate, microstructure, and mechanical properties. It
was found that melt spinning significantly altered the physical characteristics of the alloys studied. The rapid cooling rates
(∼107 K/s) produced ribbons with a low dislocation density and small (∼1 μm) low angle cells. The precipitation of γ′ was suppressed,
producing alloys with a smaller volume fraction of precipitates and lower APBE than in the conventionally cast condition.
Also, the matrix/precipitate lattice mismatch was higher in the melt spun foils. Tensile strengths were similar to those in
the conventional form; however, no measurable ductility was present. Aging the ribbons resulted in increases in γ′ volume
fraction, tensile strengths, APBE, and elongations compared to the as-cast ribbons. The results of this work suggest that
many of the microstructural refinements produced by melt spinning are lost after a short aging time at moderate temperatures. 相似文献
154.
Randy Davis 《Information Systems Management》2002,19(4):43-48
For several years now the focus of CRM has been to make it easier for companies to “reach out and touch” their customers, and vice versa. We have seen an explosion of technologies (wireless, chat, Web portals, voice recognition, analytics, and so on) that have made it convenient for customers to contact vendors, for employees to obtain information, and for companies to hone in on their most valuable assets - profitable customers. Over the last year, CRM company revenues have soared as the big get huge, and the small pick up sizable crumbs left over from the CRM table. Sure, the market is consolidating; but the CRM money machine rolls on. 相似文献
155.
Randy V. Bradley Renée M. E. Pratt Terry Anthony Byrd Christina N. Outlay Donald E. Wynn Jr. 《Information Systems Journal》2012,22(2):97-127
Despite the possible benefits of implementing healthcare information technologies, successful implementation of effective healthcare information technology is constrained by cultural and regulatory concerns and technical obstacles encountered when establishing or upgrading an organisation's enterprise infrastructure. In this paper, we advance Ross' four‐stage model of enterprise architecture maturity as a valuable IT resource for helping healthcare organisations sustain a competitive advantage. We use partial least squares (PLS) structural equation modelling to analyse survey data from 164 US hospitals at different stages of EA maturity. Our results provide evidence that enterprise architecture maturity directly influences the effectiveness of hospitals' IT resources for achieving strategic goals. Further, enterprise architecture maturity indirectly influences the effectiveness of IT resources when IT alignment is incorporated as a mediating variable. We discuss the implications of our findings for research and practice and suggest opportunities for future research. 相似文献
156.
157.
混凝土表面硅烷防水膜的电化学噪声谱分析 总被引:1,自引:0,他引:1
采用电化学噪声法研究硅烷对混凝土的防水性影响,通过统计学和傅立叶变换,对硅烷防护的混凝土试样噪声数据进行分析.结果表明,在3.5%NaCl溶液中,硅烷防护的混凝土试样电位噪声0.825 mV、电流噪声漂移值0.046 μA、噪声电阻1800.8 Ω.cm2;无硅烷防护混凝土试样电位噪声0.5 mV、电流噪声漂移值3.4... 相似文献
158.
159.
钻柱振动声波录井技术方法及应用实例 总被引:1,自引:0,他引:1
钻柱振动声波录井技术DVL(Drillstring Vibro-acoustic Logging)经过多年的室内研究和现场验证,已经取得了可喜成果,为了进一步完善其解释评价方法,该课题尚需要在现场试用中不断地深化应用研究,近期又一次开展了现场试验。简介了该技术的工作原理、配套硬件构成和无线数据传输系统的特点。结合现场应用实例.阐述了DVL技术发展最新的理论分析方法和研究成果;给出了DVL技术分析中的相关分析法和信号能量计算法;列举了频聚法、能聚法和归一化数据处理方法的理论公式和其应用方法。通过应用实例证实,依据DVL频谱图、频聚和能聚曲线、能量和相位差曲线,能有效地识别地层岩性,划分地层和油藏。同时在钻具工况的分析、辅助识别上能起到了一定的作用,为DVL技术的发展奠定了理论基础。 相似文献
160.
Recent studies on reliable wireless multicast have focused on sending acknowledgement packets from all member stations to
the source. Although these studies provide methods of improving the reliability, there have not been any studies on retransmission
methods for wireless multicast. Multicast packets are retransmitted based on the unicast transmission rule, which retransmits
until all members successfully receive the packet. In this paper, an efficient retransmission method is proposed. The retransmission
lasts until the target packet delivery ratio of each member is met. Moreover, the contention window size for retransmission
is adjusted based on the reception status of the previous transmission. The performance of the proposed wireless multicast
is evaluated by extensive simulations. 相似文献