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111.
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113.
在研究各种考勤系统的基础上,提出了一种手机蓝牙实现考勤的方法。该系统采用STM32F103RBT6微处理器作为核心,利用蓝牙模块搜索手机蓝牙设备与本地数据库进行匹配,通过语音播报和液晶显示两种方式给出考勤结果。该设计可以改变传统的被动式考勤方式,且成本低、操作简便。 相似文献
114.
设计了一种新型的高原冻土监测系统。采用ARM7内核的MCU进行控制,并基于IPv6协议利用IPv6技术和GPRS技术相结合的方式,建立了可自组网的无线传感器网络,实现了对指定区域环境参数的实时监测。系统使用了多个土壤水分传感器、温度传感器、二氧化碳传感器、氮气传感器对高原冻土环境进行全方位实时观测。各监测点将数据通过基于IPv6的无线网络传送给汇聚节点,汇聚节点再通过GPRS网络将数据传送给监控中心。监控中心可以对数据进行记录和分析,更好地指导环境保护和建设工作。 相似文献
115.
A microsecond-resolution pulse heating technique was used for the measurement of the heat of fusion of titanium and a titanium alloy (90Ti-6Al-4V). The method is based on rapid (50- to 100-s) resistive self-heating of the specimen by a high-current pulse from a capacitor discharge system and measuring, as functions of time, current through the specimen, voltage across the specimen, and radiance of the specimen. Melting of the specimen is manifested by a plateau in the measured radiance. The time integral of the net power absorbed by the specimen during melting yields the heat of fusion. The values obtained for heat of fusion were 272 J · g–1 (13.0 kJ · mol–1) for titanium and 286 J · g–1 for the alloy 90Ti-6Al-4V, with an estimated maximum uncertainty of ±6% in each value.Paper presented at the Second Workshop on Subsecond Thermophysics, September 20–21, 1990, Torino, Italy. 相似文献
116.
IPv4地址日趋枯竭,IPv6协议替代IPv4协议势在必行。与IPv4协议相比,IPv6协议在地址空间、路由聚合、服务质量和网络安全等方面带来了很大的发展和提升空间,但IPv6的网络安全仍然存在。本文对IPv6的防火墙和入侵检测系统进行了测试,并对其结果进行了分析。为正确部署防火墙和定位入侵检测系统提出了系列建议。 相似文献
117.
随着信息技术的发展,计算机网络越来越深入平时的生产生活中,家用电器网络化已经成为一种发展趋势。本文实现一种基于IPv6技术的家电网络控制电路的硬件设计。应用该方法设计的家电系统在智能化及网络化具有较好性能。 相似文献
118.
Data on adolescents' after-school experiences and their susceptibility to peer pressure were derived from surveys administered to a heterogeneous sample of 865 adolescents in Grades 5–9. Consistent with the findings of previous studies, the results show that Ss who reported home after school were not significantly different from those who were supervised by their parents at home during after-school hours. However, when a 2nd sample of latchkey children (n?=?594) was studied to include greater variation in after-school experiences, Ss who were more removed from adult supervision were found to be more susceptible to peer pressure to engage in antisocial activity. Ss who were home alone were less susceptible to peer pressure than are those who were at a friend's house after school, and those who were at a friend's house, in turn, were less susceptible than were those who describe themselves as "hanging out." Moreover, latchkey Ss whose parents knew their whereabouts and those who had been raised authoritatively were less susceptible to peer influence than were their peers, even if their afternoons were spent in contexts in which adult supervision was lax and susceptibility to peer pressure was generally high. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
Ling Yin Eric Y. J. Vancoille Kuppuswamy Ramesh Han Huang 《International Journal of Machine Tools and Manufacture》2004,44(6):607-615
Surface characterization of 6H-SiC (0001) substrates in indentation and abrasive machining was carried out to investigate microfracture, residual damage, and surface roughness associated with material removal and surface generation. Brittle versus plastic deformation was studied using Vickers indention and nano-indentation. To characterize the abrasive machining response, the 6H-SiC (0001) substrates were ground using diamond wheels with grit sizes of 25, 15 and 7 μm, and then polished with diamond suspensions of 3 and 0.05 μm. It is found that in indentation, there was a scale effect for brittle versus plastic deformation in 6H-SiC substrates. Also, in grinding, the scales of fracture and surface roughness of the substrates decreased with a decrease in diamond grit size. However, in polishing, a reduction in grit size of diamond suspensions gave no significant improvement in surface roughness. Furthermore, the results showed that fracture-free 6H-SiC (0001) surfaces were generated in polishing with the existence of the residual crystal defects, which were associated with the origin of defects in single crystal growth. 相似文献
120.
范燕 《常州信息职业技术学院学报》2021,(2):29-32
本系统以STM32F103RCT6单片机为核心控制芯片,可以一键自动测量容器内液体的重量和液位参数,并显示测量数据、判别液体种类。使用激光与浮板进行液位测量;使用压力传感器与24位AD转化模块HX711进行高精度的重量测量;利用pH值传感器、光电传感器、导电率传感器获得液体不同的物理特性,区分液体种类。系统模块构成主要包括单片机系统模块、电源模块、激光测距模块、称重模块、传感器模块、OLED显示模块和按键模块,具有多功能、测量准确、反应速度快的特点。 相似文献