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91.
基于MC37I的数传终端设计   总被引:1,自引:0,他引:1  
李明明  何通能 《机电工程》2011,28(4):482-485
为解决污染现场的数据上传(至服务中心)问题,将通用分组无线业务(GPRS)技术应用到环境污染监测领域,数据采集模块通过串口与GPRS模块连接,将数据以无线方式上传.介绍了一种基于MC37I和STC12C5A56S2无线数据传输终端的设计.研究分析了系统的硬件结构设计,介绍了PPP协议的数据包结构,重点分析了PPP协议数...  相似文献   
92.
This study examines how consumers select ecologically efficient water heaters in Japan. Energy conservation in household water heating is increasingly important for reducing an amount of CO2 emission, because the share of water heating in household energy consumption is approximately 30%. Recently, Japanese households have widely used ecologically efficient electric heat pump water heaters (Eco Cute) or gas-fired water heaters (Eco Jozu). The total number of such efficient water heaters sold in Japan was more than 2.5 million at the end of 2008. This study investigates various factors and impacts of marketing strategy for promoting the appliances in Japan. We apply mixed and nested logit models to a disaggregated choice data on water heaters from 2004 to 2008. This study considers retail energy prices, a government financial support and marketing activities as important factors for appliance selection. In addition, we consider consumers' housing attributes such as floor space and age of building. This empirical study finds two business implications. One of the two implications is that an increase in an energy price may enhance a choice probability of Eco Cute and Eco Jozu because a price increase invites consumer's consciousness on energy conservation so that a cost reduction on energy consumption becomes essential in a use of the efficient appliances. The other implication is that marketing activities, especially by recommendations from sales representatives and/or housing suppliers, are important for consumer behaviors. The other important findings are discussed in this study. This business experience in Japan is useful to the other countries where ecologically efficient water heaters are not popular at the current moment.  相似文献   
93.
Reports an error in "Marital quality and mother-child and father-child interactions with school-aged children" by Gene H. Brody, Anthony D. Pellegrini and Irving E. Sigel (Developmental Psychology, 1986[May], Vol 22[3], 291-296). In the article, the second author's name was misspelled in the issue's table of contents, title of the article, and page headings of the article. The name appears correctly in this erratum. (The following abstract of the original article appeared in record 1986-24288-001.) Mother-child and father-child teaching interactions of 60 families (parents aged 31-37 yrs, children aged 5.5-7.5 yrs) were videotaped, from which frequency counts of efficacious teaching behaviors were obtained for each parent-child teaching interaction. Parents completed the Scale of Marriage Problems. A dyad score of marital problems was formed by adding the husbands' and wives' scores, and a 2-level variable of marital problems was then derived by performing a median split on the marital problem dyad scores. Normative comparisons suggested that the couples whose scores fell below the median were characterized as nondistressed and the couples whose scores fell above the median were characterized as slightly discontented with their marital relationship. Few differences in teaching styles were found between mothers and fathers in the nondistressed group. Mothers in the slightly discontented group used more questions, positive feedback, informational feedback, and verbal task management and intruded less often into their children's learning effort than did the fathers in this group. Fathers with increased reports of marital problems used less positive feedback and were more intrusive; mothers in this group appeared to compensate for a less-than-satisfactory marriage by being more involved in teaching their children. In turn, children of slightly discontented mothers were more actively responsive to their teaching behaviors than were children of nondistressed mothers. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
This study utilized a high speed lap-shear test to evaluate the mechanical behavior of Sn-37Pb/Cu under bump metallization (UBM) solder joints under high speed loading and hence the drop reliability. The samples were aged for 120 h at different temperatures (150 °С, 180 °С) and then tested at different displacement rates in the range of 0.01 mm/s to 500 mm/s to examine the effects of aging on the drop reliability. The combination of the stress-strain graphs captured from the shear tests and the fracture morphology analysis discloses that the aging at high temperatures has influenced critically the deformation behavior of the solder joints and the effects appears more significant at high strain rates. This study demonstrates a unique capability of a drop reliability evaluation method that utilizes a high speed lap-shear test.  相似文献   
95.
The microstructure and shear strength characteristics of pure Sn and the eutectic compositions of Sn-37Pb, Sn-0.7Cu, and Sn-3.5Ag prepared under identical reflow conditions but subjected to two different cooling conditions were evaluated at room temperature. For the four solders, the ultimate shear strength increased with increasing strain rate from 10−5 s−1 to 10−1 s−1. Decreasing the cooling rate tended to decrease the ultimate shear strength for both the Sn-0.7Cu and Sn-3.5Ag solders. The effects of work hardening resulting from increased strain rate were more prevalent in quench-cooled (QC) samples.  相似文献   
96.
X-37B轨道飞行器是美国波音公司制造的第一架可重返大气层并能水平着陆、执行在轨试验任务的可重复使用无人驾驶试验机,其所采用的热防护系统不同于以往的高超飞行器.介绍了X-37B的项目概况、热防护系统与热结构,以及所用材料目前的研究状况.  相似文献   
97.
肖婉 《兵工自动化》2014,33(9):72-75
针对CPU外围芯片增多、芯片间通信要求增高,接口短缺、通信繁复等问题,以I2C在三相电参数采集模块中的应用为例,阐述STM32F37系列微控制器I2C的工作原理及工作流程。介绍了I2C接口的硬件设计、接口初始化及数据传输实现方式,并通过详述其时序、滤波器设置及数据重装载工作原理,分析它在数据传输中的优势和特点。结果表明:此I2C接口在使用中可灵活设置、准确传输,具有接口程序可移植性强、硬件设计简单等优点。  相似文献   
98.
We study bifurcations of invariant graphs in skew-product dynamical systems driven by hyperbolic surface maps T like Anosov surface diffeomorphisms or baker maps and with one-dimensional concave fibre maps under multiplicative forcing when the forcing is scaled by a parameter r = e ?t . For a range of parameters two invariant graphs (a trivial and a non-trivial one) coexist, and we use thermodynamic formalism to characterize the parameter dependence of the Hausdorff and packing dimension of the set of points where both graphs coincide. As a corollary we characterize the parameter dependence of the dimension of the global attractor : Hausdorff and packing dimension have a common value , and there is a critical parameter γ? c determined by the SRB measure of T ?1 such that for t? c and is strictly decreasing for t∈[γ? c , γmax ).  相似文献   
99.
常君  崔立军 《电子技术》2012,39(1):29-32
介绍了美国德州仪器(TI)公司的16位超低功耗单片机MSP430F135和Siemens公司TC35系列的MC37i。详细介绍了各个部分电路组成和原理。设计并实现了一种基于短信传输方式的无线工业模块。  相似文献   
100.
镇泾油田HH37P1水平井钻完井技术   总被引:4,自引:0,他引:4  
为评价水平井开发镇泾油田长8油藏的经济技术可行性,部署了HH37P1水平井。分析了该井的施工难点,提出了相应的技术对策。现场施工中通过优化钻具组合、控制井眼轨迹、调节钻井液性能及配合相应的工程工艺技术,使HH37P1水平井顺利完钻。通过测井资料结合录井显示,采用预置管柱完井方式配合后期压裂改造,初见成效。HH37P1井的成功实施为有效开发镇泾油田提供了新的途径。  相似文献   
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