基于MSP430的低功耗近距无线图像传输系统设计与实现

近距无线图像传输系统主要用于无线传感器网络中的图像采集、传输、处理和显示,本文设计并实现了一种具有较强实用性的近距无线图像传输系统。采用OV7670图像传感器作为图像数据采集器,高速低功耗的nRF24L01射频模块作为无线收发器,采用MSP430F14916位超低功耗单片机作为微处理器,所构成的系统具有功耗低、图像传输速度快等优点。作者详细阐述了该系统的硬件结构和软件设计。     

MMA7361L的高精度角度检测平台设计

倾角是许多控制系统中需要测量的一个重要参数。针对倾角测量,设计了一种基于ARM微控制器和加速度传感器的角度测量平台。该平台采用基于ARMCortex—M3内核的STM32F103VE为数据处理的核心,利用高精度加速度传感器MMA7361L为测角传感器,同时配置液晶屏和小型键盘实现了人机交互。该平台具有测量精度高、灵敏度高、价格低的特点,应用前景广阔。     

ARM和WinCE6．0下nRF24L01的驱动设计

随着嵌入式WinCE系统的发展和近距离无线通信的广泛使用,有必要为近距离无线通信芯片编写驱动。由于nRF24L01在WinCE系统下驱动的缺乏,使得WinCE与nRF24L01芯片之间的直接通信成为困难。本文的驱动设计正好解决了这一难题。     

经食道心房调搏的放射性核素心血管造影

本文应用反符合电路剔除调搏脉冲干扰的方法,制成经食道心房调搏心电心音门电路触发装置,用于经食道心房调搏的核素心血管造影。参考Tzivoni标准,当逐级增加调搏心率至140次/min或亚极量心率后发现:冠心病人有调搏后EF降低;急性心肌梗塞病人EF减低更为明显,并呈室壁反向运动。因此,心房调搏核素心血管造影有助于冠心病,特别是心肌梗塞的诊断。     

Characterization of Urine Stem Cell-Derived Extracellular Vesicles Reveals B Cell Stimulating Cargo

Elucidation of the biological functions of extracellular vesicles (EVs) and their potential roles in physiological and pathological processes is an expanding field of research. In this study, we characterized USC–derived EVs and studied their capacity to modulate the human immune response in vitro. We found that the USC–derived EVs are a heterogeneous population, ranging in size from that of micro–vesicles (150 nm–1 μm) down to that of exosomes (60–150 nm). Regarding their immunomodulatory functions, we found that upon isolation, the EVs (60–150 nm) induced B cell proliferation and IgM antibody secretion. Analysis of the EV contents unexpectedly revealed the presence of BAFF, APRIL, IL–6, and CD40L, all known to play a central role in B cell stimulation, differentiation, and humoral immunity. In regard to their effect on T cell functions, they resembled the function of mesenchymal stem cell (MSC)–derived EVs previously described, suppressing T cell response to activation. The finding that USC–derived EVs transport a potent bioactive cargo opens the door to a novel therapeutic avenue for boosting B cell responses in immunodeficiency or cancer.     

Optimization algorithm for ultra-sparse arrays in regional energy focusing

The setting of ultra-sparse arrays is one of key factors for the performance of regional energy focusing.This paper focuses on one of its typical applications:Precision Electronic Warfare by UAV,and proposes an optimization algorithm for ultra-sparse arrays to maximize the performance of regional energy focusing.First,we establish the joint optimization model of the interference waveform and the positions of elements.Second,particle swarm optimization (PSO) is adopted to iterate the positions of elements.Then,the target value of the subproblem is solved for the fitness criterion,as the current array is known in each step of the iteration.Finally,we get the optimal solution of the interference waveform and the ultra-sparse array by this method.Numerical results indicate that the algorithm can optimize the array effectively,and improve the indicators of regional energy focusing obviously.Whether the localization errors of elements exist or not,the algorithm provides a better performance than existing algorithms which only design the interference waveform.     

地区电网新能源消纳困难时段研究

文章主要研究了某实际电网新能源消纳困难时段。通过负荷特性分析,得出地区电网低谷负荷出现季节和典型日负荷特性,通过风电场、光伏电站出力特性分析,得出风电、光伏季节分布特性及日出力特性。在地区电网新能源消纳的困难时段分析基础之上,对困难时段负荷概率进行统计,得出困难时段的负荷取值,为新能源接纳能力分析提供重要的数据支撑。     

冠脉造影图像血管增强及减影的优化方法

针对于传统X射线冠状动脉造影序列图像的血管的减影包含严重伪影以及减影结果不完整等问题,提出了冠脉造影图像血管增强以及减影优化的方法。基于冠脉造影序列图像的时空特性,将相同时相的图像匹配进行减影,得到初步减影结果。针对初步减影部分缺失,对有导管遮挡没有被识别的单根血管进行二次增强处理。增强方法为:运用区域生长确定被导管遮挡的血管部分,以此部分为基础按规定模板扩展,形成覆盖导管区域,区分血管和导管,改变两部分的灰度值,增大对比度。最后采用灰度线性变换、中值滤波等步骤,得到优化的冠脉血管减影。实验表明,本减影及优化方法可以从冠脉造影序列图中提取较为完整清晰的冠脉血管并且具有很好的可控性和鲁棒性。     

Performance of Green Solvents in the Extraction of Sunflower Oil from Enzyme-Treated Collets

The main goal of this work is to evaluate the extraction of sunflower oil from enzyme-treated collets using ethanol and isopropanol (IPA) as solvents. The sunflower collets are pretreated with the multienzyme complex Viscozyme L prior to solvent extraction by the Soxhlet method. The influence of the moisture content of the collets, pretreatment, processing time, and solvent type on the amount of total extracted material and the oil extraction efficiency is studied. Some quality parameters such as phospholipid content of the oil and chlorogenic acid content of the residual meal are also analyzed. At low moisture content (7%) the solvents exhibit similar oil extraction ability (98–99%), but with increasing moisture the extraction efficiency of ethanol decreases to about 85%, while no significant differences are observed for IPA. The enzymatic treatment increases the extraction efficiency for all times, especially for ethanol. It is observed that IPA is more efficient in the extraction compared to ethanol, and the amount of nonlipid material is reduced by ≈70%. In addition, the oil extracted with IPA have lower phospholipid content and the residual meal presents a higher chlorogenic acid content. Practical Applications:This work would contribute toward the use of green solvents in the extraction of sunflower oil from collets. Ethanol and isopropanol, used as solvents, present attractive advantages, including low toxicity, good operational security, as well as being obtained from a renewable source. The obtained data provide up-to-date information on the use of these alcohols in the extraction of sunflower oil from collets and the influence of operating conditions, such as moisture content, enzymatic pretreatment of the collets, and the extraction time. Information about oil and meal quality is also reported.