Visibility threshold in sharpness for people with different regional backgrounds

Abstract— The influence of regional background on the visibility of sharpness differences has been investigated by blurring various still images to different extents. The assessment of sharpness has been performed both in China by Chinese people and in the Netherlands by European people. The results showed that both Chinese characters and Roman text were clearly more critical image material for judging sharpness than natural images. Independent on whether the image contained Chinese characters or Roman text, the visibility threshold for a difference in sharpness was the same for both the Chinese and European people. When related to a diagonal step response, the threshold on average equaled an angular resolution of 5 arcsec.     

高精度齿轮综合误差检测仪的设计

讨论了设计高精度齿轮综合误差检测仪的必要性，介绍了齿轮综合误差的检测方法和高精度齿轮综合误差检测仪的工作原理、结构特点和测量电路框图。     

Optical temperature sensor based on ZnO thin film's temperature-dependent optical properties

A reflective fiber temperature sensor system based on the ZnO thin film is proposed. The transmittance spectra and temperature dependent optical property of the sensing head with ZnO thin film is investigated theoretically and experimentally, and the temperature resolution of ～1?°C is obtained in the temperature region of 300-773 K. The temperature sensing system is only related to the wavelength shift of transmittance spectra, and has a high stability without depending on the incident light intensity. This research results also indicate a fiber optical sensor with a broad temperature measurement range (10-1800 K) can be gained as a promising temperature sensing device, and can be applied into some extremely environments, such as aircraft, nuclear power station and power transmission system, and so on.     

多向纤维缠绕小样机的研制

首先对多向纤维缠绕制品的特性进行了分析。然后以实现多向纤维缠绕为基础,从总体结构、芯模零部件设计、传动系统设计以及控制系统设计等几个方面介绍了多向纤维缠绕小样机的研制。这些将为开发功能更完备的大型多向纤维缠绕机械提供很好的实践基础。     

蒙特卡罗在圆度测量精度分析中的应用研究

根据三点法圆度测量的基本原理,重点分析了三测头的测量误差对圆度测量精度的影响.由于三测头测量误差的传递关系非常复杂,因此作者提出了一种采用Monte Carlo随机抽样和随机模拟对此进行分析的方法,直观地确定了由测头测量误差引起的工件轮廓上各点的圆度测量标准差,并通过仿真证明了该方法是有效的.     

Fluxing Agents on Ceramification of Composites of MgO-Al<Subscript>2</Subscript>O<Subscript>3</Subscript>-SiO<Subscript>2</Subscript>/Boron Phenolic Resin

Fluxing agents of zinc borate, antimony oxide, galss frit A and glass frit B, with different melting or softening point temperatures, were added into MgO-Al₂O₃-SiO₂/boron phenol formaldehyde resin (MAS/BPF) composites to lower the formation temperature of eutectic liquid phase and promote the ceramification of ceramifiable composites. The effects of fluxing agents on the thermogravimetric properties, phase evolution, and microstructure evolution of MAS / BPF composites were characterized by TG-DSC, XRD and SEM analyses. The results reveal that the addition of a fluxing agent highly reduces the decomposition rate of MAS / BPF composites. Fluxing agents lower the formation temperatures of liquid phases of ceramifiable MAS / BPF composites obviously, and then promote the ceramification and densification process. The final residues of composites are ceramic surrounded by large amount of glass phases.     

Performance evaluation of a new signal processing system design to improve CANDU SDS1 trip response during large break LOCA events

Performance of a recently developed signal processing system for CANDU (Canada Deuterium Uraniu) reactor shutdown system 1 (SDS1) is evaluated in this paper. The evaluation is carried out in MATLAB/Simulink software environment as well as with an existing power measurement and signal processing system. The new signal processing algorithm is obtained based on the synthesis of several first order low pass filters with different delayed time constants. Throughout this paper, a special attention has been paid to compare the new signal processing system with the existing one. The dynamic behavior of the new signal processing system in the practical large loss of coolant accidents (LLOCA) events has also been examined. Simulation results show that during the LLOCA event, the reactor trip time, as well as the peak power, is decreased remarkably. Through the simulation studies, it has convincingly demonstrated that the new signal processing system has significant advantages over the existing system in terms of the improved trip response and accommodation of the spurious trip immunity. This advantage will significantly enhance the safety margin, or will bring economical benefits to nuclear power plants.