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71.
基于标准0.18μm CMOS工艺和低功耗设计方法设计了集成温度传感器所需的3个重要电流产生电路,即与温度成正比的电流,与温度成反比的电流和稳定的、不随温度及电源电压变化的电流产生电路。采用低功耗设计方法解决了自然效应对温度传感器的影响。采用TSMC所提供的BSIM3V3模型进行仿真,电路在-40~120℃具有高线性度、高稳定度。同时电路具有低压、低功耗的优点,并且有良好的移植性,可使用于更多更广泛的吻合。  相似文献   
72.
提高脉冲激光打孔质量的措施   总被引:2,自引:0,他引:2  
分析JG-2A型脉冲激光器打孔过程中存在的质量问题及其影响因素。同时提出了改善打孔质量的措施:(1)根据最小二乘法原理建立脉冲激光能量经验公式来选取工艺参数;(2)谐振腔超声调制法;(3)材料的热吸收效应法。在实际应用中,打孔质量明显改善。  相似文献   
73.
从大事件营销的角度对南通市新城区的发展进行分析,指出南通市通过省运会这一大事件,激活周边地块的价值提升并产生连锁反应,从而对地区发展形成显著的触媒作用。这一过程为南通新市级中心周边地区带来发展机遇,同时也通过促进地区功能完善和城市结构整合,为城市长期发展提供持续强大的推动力。实证研究表明,不仅仅是大城市,二、三线城市也可以通过大事件的机遇实现地区腾飞,大事件营销正成为一种日益普遍的推动城市发展的政府手段。  相似文献   
74.
Photocatalytic ozonation of organics under simulated solar irradiation with a g-C3N4 nanosheet was investigated. g-C3N4 was prepared by calcinations of urea and characterized by TEM, BET, XRD and UV-Vis. Oxalic acid and bisphenol A were used as model substances to evaluate its catalytic ability. The results showed that g-C3N4 possess 2D nanosheet structure. The degradation ratio of oxalic acid and bisphenol A with g-C3N4/O3/Solar was 1.50 and 1.92 times as great as the sum ratio when it was individually degraded by g-C3N4/Solar and O3, separately. The results of recycling experiment indicated that g-C3N4 catalyst is very stable under experimental conditions.  相似文献   
75.
Increasing energy efficiency is a cornerstone of policy initiatives to tackle climate change and increase corporate sustainability. Convincing people to drive more fuel-efficiently (“eco-driving”) is often an integral part of these approaches, especially in the transport sector. But there is a lack of studies on the long-term persistence and potential interaction of the effects of incentives and training on energy conservation behavior in general and eco-driving behavior in particular. We address this gap with a twelve months long natural field experiment in a logistics company to analyze the time-dependent and potentially interacting effects of rewards and theoretical training for eco-driving on fuel consumption in a real-world setting. We find an immediate reduction of fuel consumption following the introduction of a non-monetary reward and an attenuation of this effect over time. Theoretical eco-driving training shows no effect, neither short-term nor long-term, highlighting the often neglected necessity to include practical training elements. Contrary to common assumptions, the interaction of incentives and theoretical training does not show an additional reduction effect. Our results demonstrate the difficulty of changing engrained behavior and habits, and underline the need for a careful selection and combination of interventions. Policy implications for public and private actors are discussed.  相似文献   
76.
We utilize the close link between Cohen’s d, the effect size in an ANOVA framework, and the Thurstonian (Signal detection) d-prime to suggest better visualizations and interpretations of standard sensory and consumer data mixed model ANOVA results. The basic and straightforward idea is to interpret effects relative to the residual error and to choose the proper effect size measure. For multi-attribute bar plots of F-statistics this amounts, in balanced settings, to a simple transformation of the bar heights to get them transformed into depicting what can be seen as approximately the average pairwise d-primes between products. For extensions of such multi-attribute bar plots into more complex models, similar transformations are suggested and become more important as the transformation depends on the number of observations within factor levels, and hence makes bar heights better comparable for factors with differences in number of levels. For mixed models, where in general the relevant error terms for the fixed effects are not the pure residual error, it is suggested to base the d-prime-like interpretation on the residual error. The methods are illustrated on a multifactorial sensory profile data set and compared to actual d-prime calculations based on Thurstonian regression modeling through the ordinal package. For more challenging cases we offer a generic “plug-in” implementation of a version of the method as part of the R-package SensMixed. We discuss and clarify the bias mechanisms inherently challenging effect size measure estimates in ANOVA settings.  相似文献   
77.
简述国内平巷掘进机械化作业线的配套方式和适用条件,介绍了广西大新锰矿280m平硐掘进机械化作业线的配套方式。采用YT-28气腿式凿岩机、LD-120型挖斗式装岩机、8m3的S8型梭式矿车和10 t架线式电机车机械化作业线配套方式取得较好效果。  相似文献   
78.
The bulk mechanical properties of two different types of rootzone sands (round and angular) were measured using a cubical triaxial tester. Two monosize sands (d 50 = 0.375 mm and 0.675 mm) and their 50:50 binary mixtures (d 50 = 0.500 mm) were studied. The compression, shear, and failure responses of the above-mentioned six compositions were analyzed, compared, and modeled. Two elastic parameters (bulk and shear moduli) and two elastoplastic parameters (swelling and consolidation indices) of the six sand compositions were also calculated and compared. The angular sand was more compressible than round sand during isotropic compression. In addition, the angular sands tended to have lower initial bulk density and high porosity values. Among the three different size fractions, the 0.375 mm mixture was least compressible for both sand shapes. The failure strength and shear modulus of the angular sand were higher than the round sands. In addition, due to their simplicity, phenomenological models were developed to predict the compression and shear behavior of the sands. The prediction models were validated using subangular and subround sands. Average relative difference values were calculated to determine the effectiveness of the prediction models. The mean average relative difference values for compression profiles, i.e., volumetric stress vs. volumetric strain, were from 16 % to 39 %, except for the initial load-response portion (< 1 % volumetric strain). The predictive models were effective in reproducing the failure responses: at 17.2 kPa confining pressure, the mean of average relative difference was 23 %; at 34.5 kPa , the mean difference was 24 %.  相似文献   
79.
80.
通过向镁熔体中单独和复合添加一定量的Cu及Zn元素,探究了Cu、Zn对镁晶粒尺寸和微观组织的影响并阐释了其细化机理;同时深入表征了Cu、Zn单独及复合添加后合金的物相组成。结果表明:向纯Mg中加入Cu、Zn和Cu、Zn复合添加后,晶粒依次由柱状晶转变为等轴晶。单独加Cu、单独加Zn和Cu、Zn复合添加后,平均晶粒尺寸由纯Mg的1270μm分别减小至470、120和85μm。单独加Zn对Mg的晶粒细化机理主要为Zn元素的溶质效应;单独加Cu对Mg的晶粒细化机理主要为Cu元素的溶质效应和CuMg2相对晶界的钉扎作用;Cu、Zn复合添加后细化效果更好主要是因为Cu、Zn元素的复合溶质效应及第二相对晶界的钉扎作用更为强烈。此外,单独加Zn后,第二相呈颗粒状分布于基体中,合金中的物相组成为α-Mg+MgZn;单独加Cu后,第二相形貌呈网状,合金中的物相组成为α-Mg+CuMg2;Cu、Zn复合添加后,Mg-5Cu-3Zn晶界上的第二相呈现出两种不同的形貌,经鉴定,连续的块状第二相为CuMg2相,不连续的鱼骨状第二相为CuMgZn相。  相似文献   
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