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1.
基于ISPl581的USB2.0键盘数码管控制设备的设计严格遵循USB2.0协议,体现了USB即插即用、易扩展、低干扰的特点,实现了主机和设备之间简单、快速、可靠的连接和通信。文章介绍了基于ISP1581的USB2.0键盘数码管控制设备的硬件、软件的设计方法。 相似文献
2.
Simon Piché 《Chemical engineering science》2005,60(22):6452-6461
The oxidative absorption of hydrogen sulfide (H2S) into a solution of ferric chelate of trans-1,2- diaminocyclohexanetetraacetate (CDTA) was studied in a counter-current laboratory column randomly packed with 15 mm plastic Ralu rings. The present investigation takes concern about the Kraft pulping situation where dilute H2S concentrations are omnipresent in large-volume gas effluents. A fractional two-level factorial approach was instigated to determine the significance of six operating variables, namely the solution's alkalinity (pH; 8.5-10.5), the liquid mass flow rate (L;1.73-), the solution's ionic strength (IC;0.01-), the gas mass flow rate (G;0.19-), the inlet H2S concentration (CH2S,0;70-430 ppm) and the initial ferric CDTA concentration (CFe,0;100 -). Initially, a Plackett-Burman design matrix of seven duplicated experiments revealed that pH is the leading factor controlling the H2S conversion rate while the ionic strength and ferric CDTA concentration effects remained negligible within the factorial domain. Surface response analysis based on 11 duplicated factorial experiments plus 10 central composite trials revealed that the H2S conversion significantly increases with liquid flow rate but decreases with growing H2S load up. Further examination about the influence of ferric CDTA on H2S absorption rate was set up over a broader concentration range (CFe,0;0- at pH of 9.5 and 10.5. It showed good potential at as H2S conversion increased by a significant 25% for both pH values in comparison to pure alkaline solutions containing no ferric CDTA. 相似文献
3.
In this paper, by using the concept of (A,η)-accretive mappings and the new resolvent operator technique associated with (A,η)-accretive mappings, we introduce and study a system of general mixed quasivariational inclusions involving (A,η)-accretive mappings in Banach spaces, and construct a new perturbed iterative algorithm with mixed errors for this system of nonlinear (A,η)-accretive variational inclusions in q-uniformly smooth Banach spaces. Our results improve and generalize the corresponding results of recent works. 相似文献
4.
Guochang Wang 《Computational statistics & data analysis》2012,56(3):587-601
Functional linear regression has been widely used to model the relationship between a scalar response and functional predictors. If the original data do not satisfy the linear assumption, an intuitive solution is to perform some transformation such that transformed data will be linearly related. The problem of finding such transformations has been rather neglected in the development of functional data analysis tools. In this paper, we consider transformation on the response variable in functional linear regression and propose a nonparametric transformation model in which we use spline functions to construct the transformation function. The functional regression coefficients are then estimated by an innovative procedure called mixed data canonical correlation analysis (MDCCA). MDCCA is analogous to the canonical correlation analysis between two multivariate samples, but is between a multivariate sample and a set of functional data. Here, we apply the MDCCA to the projection of the transformation function on the B-spline space and the functional predictors. We then show that our estimates agree with the regularized functional least squares estimate for the transformation model subject to a scale multiplication. The dimension of the space of spline transformations can be determined by a model selection principle. Typically, a very small number of B-spline knots is needed. Real and simulation data examples are further presented to demonstrate the value of this approach. 相似文献
5.
ICT infrastructure investments in educational institutions have been one of the key priorities of education policy during the last decade. Despite the attention, research on the effectiveness and efficiency of ICT is inconclusive. This is mainly due to small-scale research with weak identification strategies which lack a proper control group. Using the 2011 ‘Trends in International Mathematics and Science Study’ (TIMSS) data, we define by a Mahalanobis matching a control group with similar student, teacher, school and regional characteristics. The results indicate that accounting or not accounting for these characteristics, may considerably alter the estimated impact of ICT. This suggests that a correction for characteristics related to the student population, teaching staff, administrative personnel and school management is warranted in the evaluation of the impact of ICT. 相似文献
6.
介绍了以STC15F2K61S2为控制核心,通过太阳能或者可充电电池供电,并采集蓝牙模块、氧气传感器、DS18B20温度传感器等传感器数据数据,然后经过处理芯片对数据进行进行数据处理及分析,将相关数据显示在12864液晶显示屏上,同时在安卓手机安装手机通信助手软件,或者结合电脑利用RS232串口与单片机进行通信,便可对家电进行相应的操作,从而实现家居智能化控制的目的. 相似文献
7.
为了预测ZK61M高强镁合金板热变形过程的韧性断裂行为,在一定条件下进行实验和数值模拟。基于获得的各试件断口处的应力状态参数和断裂应变数据,采用粒子群优化算法求解4种断裂模型中的待定系数。依据误差评估结果,确定改进的Wilkins模型精度最高。将改进的Wilkins模型引入有限元中,并与实验进行对比。结果表明,预测的拉伸件断裂位移和断裂载荷的平均误差均小于15%,预测的圆筒形件成形深度的平均误差为13.88%,建立的有限元模型可以较为准确地模拟实验过程并预测断裂位置。 相似文献
8.
The endoplasmic reticulum represents the gateway to the secretory pathway. Here, proteins destined for secretion, as well as soluble and membrane proteins that reside in the endomembrane system and plasma membrane, are triaged from proteins that will remain in the cytosol or be targeted to other cellular organelles. This process requires the faithful recognition of specific targeting signals and subsequent delivery mechanisms to then target them to the translocases present at the ER membrane, which can either translocate them into the ER lumen or insert them into the lipid bilayer. This review focuses on the current understanding of the first step in this process representing the targeting phase. Targeting is typically mediated by cleavable N-terminal hydrophobic signal sequences or internal membrane anchor sequences; these can either be captured co-translationally at the ribosome or recognised post-translationally and then delivered to the ER translocases. Location and features of the targeting sequence dictate which of several overlapping targeting pathway substrates will be used. Mutations in the targeting machinery or targeting signals can be linked to diseases. 相似文献
9.
针对DTHS-A单片机实验平台的日常维护需要设计了该测试装置,该装置能够快速的检测实验电路中驱动芯片是否正常,与传统方法相比,节约了维护的时间,提高了检测效率.该装置以STC15F2K61S2为控制核心,通过按键与拨码开关来选择对应芯片,通过液晶显示与LED指示芯片是否正常,同时具有过流保护功能. 相似文献
10.
Lee?HuskeyEmail author Matthew?Berman Alexandra?Hill 《The Annals of Regional Science》2004,38(1):75-92
We investigate determinants of the pattern of recent migration of Alaska Natives between rural homelands and urban areas. A review of the literature on moving in the North American North suggests that economic opportunities draw migrants, although such opportunities must be viewed in the context of the mixed subsistence-cash economy prevailing in rural areas of the region. Consequently, we model Native migration as a simultaneous decision with labor market participation in a mixed economy. Estimated equations explaining individual Alaska Native migration choices using the U.S. Census Public Use Microdata Sample (PUMS) are consistent with the model, and also suggest that perceived opportunities differ between women and men.The authors acknowledge financial support from the National Science Foundation, grant OPP-9521459. An earlier version of this paper was presented to the 1998 annual meeting of the Western Regional Science Association 相似文献