带环形内侧凹塑件注射模设计

根据带环形内侧凹塑件的结构特点 ,讨论了成型时塑件可采取的脱模方式 ,分析了采用顺序脱模机构时型芯的分割方法及型芯的运动过程 ,探讨了不同结构的塑件在脱模时采用的抽芯机构 ,设计出2种模具结构并指出设计时的注意事项。     

A compact dual band short ended metamaterial antenna with extended bandwidth

A compact dual‐band CPW–fed metamaterial inspired antenna using Composite Right/Left Handed (CRLH) resonant approach is presented in this article. The antenna is designed such that it can be operated in series resonant mode where resonance behavior is characterized by series LC parameters. Proposed antenna comprises two annular ring resonators connected with the signal patch intended to excite the higher order modes. This results extension of second band from 51.4% (f_c = 6.92 GHz) to 69.2% (f_c = 7.35 GHz). In addition to that proposed antenna shows compact nature with an electrical size of 0.14 λ₀ × 0.21 λ0 × 0.01 λ₀ at f₀ = 2.18 GHz. The antenna is operating over 2.14–2.23 GHz, 4.81–9.90 GHz with simulated peak gain of 0.66 and 4.44 dB, respectively. Simulated radiation efficiencies of proposed antenna are 69.8 and 94.1% throughout first and second band, respectively. To examine the resonance and radiation characteristics prototype is fabricated and measured. Observed experimental results are in good agreement with those simulated one. These characteristics makes this antenna is a good candidate for modern wireless communication systems such as Bluetooth, WLAN/Wi‐Fi band. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:435–441, 2016.     

Annular ring slot antenna design with reconfigurable polarization

A microstrip‐fed conventional annular ring slot (ARS) antenna with linear polarization (LP) is initially studied. To generate two orthogonal degenerate modes for circular polarization (CP) radiations, two identical meandering perturbation slots (MPS) are symmetrically loaded into the ARS. By further incorporating a PIN diode switch across each MPS, the proposed antenna can switch between left‐hand CP (LHCP), right‐hand CP (RHCP), and LP. All three polarizations have shown good impedance bandwidth and broad CP bandwidth that can satisfy the wireless local area network (WLAN) 2.4‐GHz operating band (2400–2480 MHz). Furthermore, desirable gains of 1.8–2.0 dBi and 2.40–2.84 dBic are also exhibited at LP and LHCP/RHCP, respectively. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:110–120, 2016.     

The effect of vacancies on the annular dark field image contrast of grain boundaries: a SrTiO(3) case study

The analysis of grain boundary structure in high resolution electron microscopy is often hindered by contrast variation within the grain boundary region which is not explained by simple models of the grain boundary structure. Recent work suggests that structural disorder along the beam direction and the presence of vacancies contribute significantly to this effect. One might expect a significant reduction in contrast in a Z-contrast image of a grain boundary would imply that vacancies present must result from the absence of heavier elements. Using a [001](210) Σ5 grain boundary in SrTiO₃ as a test case and first principles structure relaxation to calculate stable defect structures, we show that the reduction in the intensity from fully occupied Sr columns due to the structural distortion resulting from a nearby O vacancy can be as great as that due to introducing a Sr vacancy in the column itself. The effect on energy dispersive X-ray spectroscopy signals is also considered, but found to be smaller than that on Z-contrast images.     

综合颜色和Contourlet直方图的图像检索方法

为提高图像检索性能,使用Harris彩色点提取器提取颜色特征点,设计一种基于颜色特征点的环形颜色直方图,在对图像进行Contourlet变换的基础上,提出Contourlet直方图的概念,改进其旋转不变性,并提取图像的纹理信息。仿真实验结果表明,该方法能够快速准确地检索彩色图像。     

预氯化对输水管道净水效能影响及恢复研究

为保障原水输水过程中水质安全性,采用生物膜环状反应器(BAR, Biofilms Annular Reactor)考察预氯化对管道生物膜净水效能的影响及其性能恢复过程．结果表明,管道预氯化后,对管道生物膜损伤较大,影响NH₄+-N、NO₂--N、CODMn、TP去除效果;出水出现短暂的CODMn和TP质量浓度上升、NO₂--N积累现象,出水NO₂--N最大积累量可达7倍．冲击实验后稳定运行阶段,生物膜对NH₄+-N去除效能恢复时间较NO₂--N快2 d,NH₄+-N、NO₂--N分别在第8天和第10天完成恢复;稳定运行至第8天,管壁生物膜完成对CODMn和TP去除效能的恢复．     

翻驳领纸样的参数化设计

分析翻驳领纸样设计中的翻折基点和翻领松量等关键影响因素，实现了基于服装CAD的翻驳领纸样参数化设计．这种方法能充分发挥服装CAD软件的优势，有利于提高纸样设计的质量和效率．     

优化PID参数减小环形炉控制温差

用PID参数控制炉子热工，更有利于热工参数的优化。在优化过程中，通过对PID参数影响因素的调整和改善，使其参数更趋合理，最终使环形炉达到了理想的加热和控制效果。     

球团环冷机高温段烟罩内环侧密封板耐热层的改进

鲁南矿业公司链篦机-回转窑-环冷机氧化球团工艺中,环冷机高温段烟罩内环侧密封板耐热层原采用耐火材料整体浇注.使用一段时间后出现了浇注料开裂和脱落,后改用高强预制砖挂靠在密封板上,有效地解决了因浇注料开裂、脱落影响球团生产的诸多问题.     

热过屈曲正交异性圆(环)板的自由振动响应

基于vonKármán薄板几何非线性理论,建立了以中面位移为基本未知量的加热极正交异性圆板轴对称大挠度动力学控制方程。然后,将控制方程的响应分解为热过屈曲静态解和振动解两部分,并在小振幅振动假设下得到了板在热过屈曲静平衡构形附近自由振动的线性微分方程。最后,采用打靶法获得了板在热过屈曲前后的固有频率与升温参数之间的特征关系曲线。结果表明,周边面内约束板的前两阶固有频率在热屈曲前随着温度升高而降低,而一旦板进入过屈曲平衡状态,前两阶频率都随着升温而单调增加。