We studied the effect of salinity on nail-hold- ing power in wood construction. In saline solution, the holding power of nails was less than in purified water. With the increase of salt concentration, the surface and ...We studied the effect of salinity on nail-hold- ing power in wood construction. In saline solution, the holding power of nails was less than in purified water. With the increase of salt concentration, the surface and side nail- holding power of the wood specimens both declined, but the differences between salinity treatments were not sig- nificant. However, compared to the surface and side nail- holding power, the power on the edge was generally less and the difference was not obvious in different salt con- centrations. In the same salt concentration, with the extension of the processing cycle, the performance of holding power of nails showed a downward trend, expect the temporary rise in the middle.展开更多
This study describes how one can construct sets of composite natural numbers as tensorial products of the vectors created with the natural powers of prime numbers.
At high speeds and high resolution, the Pipeline ADCs are becoming popular. The options of different stage resolutions in Pipelined ADCs and their effect on speed, power dissipation, linearity and area are discussed i...At high speeds and high resolution, the Pipeline ADCs are becoming popular. The options of different stage resolutions in Pipelined ADCs and their effect on speed, power dissipation, linearity and area are discussed in this paper. The basic building blocks viz. Op-Amp Sample and Hold circuit, sub converter, D/A Converter and residue amplifier used in every stage is assumed to be identical. The sub converters are implemented using flash architectures. The paper implements a 10-bit 50 Mega Samples/Sec Pipelined A/D Converter using 1, 1.5, 2, 3, 4 and 5 bits/stage conversion techniques and discusses about its impact on speed, power, area, and linearity. The design implementation uses 0.18 μm CMOS technology and a 3.3 V power supply. The paper concludes stating that a resolution of 2 bits/stage is optimum for a Pipelined ADC and to reduce the design complexity, we may go up to 3 bits/stage.展开更多
电力系统的自动发电控制(automaticgeneration control,AGC)是典型的采样控制系统,具有调节周期长、通信延迟显著的特点。基于单区域负荷频率控制(load frequency control,LFC)系统,该文提出一种适用于考虑AGC采样保持特性的时滞电力系...电力系统的自动发电控制(automaticgeneration control,AGC)是典型的采样控制系统,具有调节周期长、通信延迟显著的特点。基于单区域负荷频率控制(load frequency control,LFC)系统,该文提出一种适用于考虑AGC采样保持特性的时滞电力系统频率稳定性分析方法。首先利用零阶保持器建立考虑AGC采样保持特性的LFC连续–采样混合系统模型;然后利用切比雪夫离散化方法处理模型中的时滞变量,基于函数空间方法建立等值的离散化系统;随后提出基于离散化系统特征值的稳定性判据。为说明考虑AGC采样保持特性的必要性,该文还建立了忽略AGC采样保持特性和用零阶保持器连续传递函数建模的LFC连续系统模型,通过比较不同模型的时滞稳定裕度说明不同建模方法的保守冒进程度。最后通过时滞稳定裕度上的时频域仿真分析验证所提稳定性分析方法的准确性。展开更多
基金financially supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Jiangsu Overseas Research&Training Program for University Prominent Young&Middle-aged Teachers and Presidents
文摘We studied the effect of salinity on nail-hold- ing power in wood construction. In saline solution, the holding power of nails was less than in purified water. With the increase of salt concentration, the surface and side nail- holding power of the wood specimens both declined, but the differences between salinity treatments were not sig- nificant. However, compared to the surface and side nail- holding power, the power on the edge was generally less and the difference was not obvious in different salt con- centrations. In the same salt concentration, with the extension of the processing cycle, the performance of holding power of nails showed a downward trend, expect the temporary rise in the middle.
文摘This study describes how one can construct sets of composite natural numbers as tensorial products of the vectors created with the natural powers of prime numbers.
文摘At high speeds and high resolution, the Pipeline ADCs are becoming popular. The options of different stage resolutions in Pipelined ADCs and their effect on speed, power dissipation, linearity and area are discussed in this paper. The basic building blocks viz. Op-Amp Sample and Hold circuit, sub converter, D/A Converter and residue amplifier used in every stage is assumed to be identical. The sub converters are implemented using flash architectures. The paper implements a 10-bit 50 Mega Samples/Sec Pipelined A/D Converter using 1, 1.5, 2, 3, 4 and 5 bits/stage conversion techniques and discusses about its impact on speed, power, area, and linearity. The design implementation uses 0.18 μm CMOS technology and a 3.3 V power supply. The paper concludes stating that a resolution of 2 bits/stage is optimum for a Pipelined ADC and to reduce the design complexity, we may go up to 3 bits/stage.
文摘电力系统的自动发电控制(automaticgeneration control,AGC)是典型的采样控制系统,具有调节周期长、通信延迟显著的特点。基于单区域负荷频率控制(load frequency control,LFC)系统,该文提出一种适用于考虑AGC采样保持特性的时滞电力系统频率稳定性分析方法。首先利用零阶保持器建立考虑AGC采样保持特性的LFC连续–采样混合系统模型;然后利用切比雪夫离散化方法处理模型中的时滞变量,基于函数空间方法建立等值的离散化系统;随后提出基于离散化系统特征值的稳定性判据。为说明考虑AGC采样保持特性的必要性,该文还建立了忽略AGC采样保持特性和用零阶保持器连续传递函数建模的LFC连续系统模型,通过比较不同模型的时滞稳定裕度说明不同建模方法的保守冒进程度。最后通过时滞稳定裕度上的时频域仿真分析验证所提稳定性分析方法的准确性。
