无梭织机经纱张力波动特点与微机控制电子送经系统分析

分析了无梭织机经纱张力波动特点以及电子送经系统检测和补偿经纱张力的原理。通过对四种电子送经后梁系统的分析指出：①高频率的经纱张力波动由弹性后梁的高速摆动来补偿；低频率的经纱张力波动由电子送经装置通过送经量的调节来补偿。②以拉力传感器作为检测元件时，送经装置是以一个织造周期中经纱张力的平均值作为控制目标进行张力的ＰＩＤ控制；以接近开关作为检测元件时送经装置则是通过检测后梁的位置进行张力控制。③对ＪＡＴ６００喷气织机以拉力传感器作为检测元件的ＰＩＤ控制模式进行了详尽的分析说明。     

IBMPC与MCS—51二级系统的通讯设计

给出了用ＩＣＬ２３２实现ＩＢＭ ＰＣ与ＭＣＳ－５１第一单片机二级系统串行的硬件电路和通讯软件，介绍了低功耗通讯系统的方法，实际应用效果良好。     

生态猪的健康养殖与疾病预防技术

根据影响生态猪健康成长的几点要素,合理阐述如何实施更好的生态猪养殖。对当前现有的生态猪养殖模式进行科学分析,总结养殖要点。结合实际情况,提出生态猪疾病预防的有效措施,对生态猪养殖未来发展趋势做出讨论。     

低渗透油藏渗吸采油技术研究进展*

针对低渗透油藏渗吸采油技术,运用文献调研的方式,介绍了渗吸采油相关概念,综述了低渗透油藏渗吸 采油技术在渗吸机理和应用方面的研究成果与最新研究进展,对低渗透油藏渗吸采油技术在室内实验和现场应 用中的发展趋势进行了技术展望。     

选择计量器具检定周期的几点建议

合理选择计量器具检定周期,可以从以下几个方面考虑:     

计量检定室内温度和相对湿度的测定

1　室内温度的测定一般精度的空调系统 ,可用 0 1℃分度的水银温度计测定 ,高精度的空调系统可用 0 0 1℃的水银温度计或小量程温度自动记录仪测定。2　室内相对湿度的测定可用带小风扇的干湿球温度计或电湿度计测定。使用干湿球温度计时应注意 :(1)包裹湿球温度计的纱布力求松软 ,并有良好的吸水性 ;(2 )测定时 ,应尽快读数 ,并避免对着温、湿度计急速呼吸 ,以保证测定的准确性 ;(3)纱布未浸水前 ,干球温度计和湿球温度计的读数差不应大于 0 1℃。使用电湿度计时应注意 :(1)测头是关键部件 ,易损坏 ,需特别小心。使用时 ,只能拿测头的塑…     

标准孔板节流装置的应用及其探讨

分析了标准孔板节流装置的测流原理。在测流原理的基础上对标准孔板节流装置的可压缩流体（如天然气）流量测量不确定度进行估算,并且介绍了装置的使用和安装方法,及在使用中出现部分流量测量偏离标准规定的处理方法。     

一种针对中国超宽带标准的CMOS PA

A 6–9 GHz ultra-wideband CMOS power amplifier (PA) for the high frequency band of China's UWB standard is proposed. Compared with the conventional band-pass filter wideband input matching methodology, the number of inductors is saved by the resistive feedback complementary amplifying topology presented. The output impendence matching network utilized is very simple but efficient at the cost of only one inductor. The measured S₂₂ far exceeds that of similar work. The PA is designed and fabricated with TSMC 0.18 μ m 1P6M RF CMOS technology. The implemented PA achieves a power gain of 10 dB with a ripple of 0.6 dB, and S₁₁ < –10 dB over 6–9 GHz, S₂₂ < –35 dB over 4–10 GHz. The measured output power at the 1 dB compression point is over 3.5 dBm from 6 to 9 GHz. The PA dissipates a total power of 21 mW from a 1.8 V power supply. The chip size is 1.1 × 0.8 mm².     

A 6-9 GHz ultra-wideband CMOS PA for China's ultra-wideband standard

A 6-9 GHz ultra-wideband CMOS power amplifier(PA) for the high frequency band of China's UWB standard is proposed.Compared with the conventional band-pass filter wideband input matching methodology,the number of inductors is saved by the resistive feedback complementary amplifying topology presented.The output impendence matching network utilized is very simple but efficient at the cost of only one inductor.The measured S_(22) far exceeds that of similar work.The PA is designed and fabricated with TSMC 0...     

A 264 MHz CMOS Gm-C LPF for ultra-wideband standard

A 264 MHz CMOS 4th G_m-C LPF target for the UWB standard is presented.The filter is designed by cascading two biquad cells.Compared with the previously published biquad cells,the biquad proposed here saves 1 transconductor,3 CMFB networks and 2 capacitors.Benefiting from these merits,the power consumption and chip area of the 4th order UWB LPF are reduced dramatically without other characteristics being affected.The LPF is designed and fabricated with TSMC 0.18μm 1P6M CMOS technology.The implemented LPF ...