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101.
介绍健康测试仪中的液晶显示技术。给出了该测试仪中液晶显示器的设计、液晶驱动芯片的选择、与控制器的硬件接口和部分驱动子程序。  相似文献   
102.
A mobile medical information system (MMIS) is an integrated application (app) of traditional hospital information systems (HIS) which comprise a picture archiving and communications system (PACS), laboratory information system (LIS), pharmaceutical management information system (PMIS), radiology information system (RIS), and nursing information system (NIS). A dynamic resource allocation table is critical for optimizing the performance to the mobile system, including the doctors, nurses, or other relevant health workers. We have designed a smart dynamic resource allocation model by using the C4.5 algorithm and cumulative distribution for optimizing the weight of resource allocated for the five major attributes in a cooperation communications system. Weka is used in this study. The class of concept is the performance of the app, optimal or suboptimal. Three generations of optimization of the weight in accordance with the optimizing rate are shown.  相似文献   
103.
滤波窗口是影响椒盐噪声滤除效果的重要因素。针对自适应中值滤波算法(RAMF)的不足,提出了一种基于窗口的自适应中值滤波算法。该算法分为噪声的检测和滤除两部分。在噪声检测部分,主要通过混合窗口检测出准噪声点,将其用窗口中值代替,而其余信号点保持不变。重复此方法,直至所有的准噪声点处理完毕。然后,在噪声滤除部分,主要根据噪声密度选择合适的最大滤波窗口半径,进而实现噪声滤除。最后,为验证算法的有效性开展了仿真研究,仿真结果表明本算法对椒盐噪声的滤除具有很好的效果,增强了图像的清晰度。  相似文献   
104.
分别以碳酸盐和硝酸盐为前驱体,采用熔盐法在750~1050℃合成了针状的Sr0.5Ba0.5Nb2O6(SBN50)模板晶粒。通过XRD,SEM分析方法,研究了前驱体对SBN50晶粒相结构和微观形貌的影响,并讨论了其形成机理。结果表明:前驱体性质的不同造成熔盐熔点时SrNb2O6数量和形貌的差异,影响最终SBN50晶粒的形貌;SBN50晶粒的生长是二维成核过程。  相似文献   
105.
采用共沉淀–熔盐法制备了M型铁氧体BaFe11.85-2xCoxTixMn0.15O19。运用TGA-DTA、XRD、SEM和矢量网络分析仪,对样品的晶化过程、相组成、显微形貌及微波吸收性能进行了表征。结果表明:Co2+、Ti4+固溶到铁氧体的晶格并取代Fe3+位,有助于提高铁氧体的电、磁损耗。当取代量x为1.2时,微波吸收最强,制得的样品的吸波频率在8.2~12.4 GHz范围内,tanδe、tanδμ的最大值分别为:9.0,6.8。  相似文献   
106.
以BH—G/K玻璃为基体,以添加Al2O3粉的DM—308玻璃为表层区研制出与金属外壳封接的双层玻坯。分析了Al2O3粒度及添加量对熟坯致密化和线收缩率的影响。结果表明,表层区使用添加质量分数为20%和30%0.5μm粒径Al2O3粉的DM—308玻璃可以实现熟坯的匹配收缩,用于UP2113—14外壳熔封。电镀后外壳气密性、绝缘电阻均有数量级提高,玻璃沿引线上爬高度只为BH—G/K玻璃的1/3,显著降低外壳盐雾试验后引线根部易锈蚀和引线受力后绝缘子开裂的风险。  相似文献   
107.
本文提出了一种双梁互补式光纤光栅(fiber Bragg grating, FBG)位移传感器,实现了正负双向位移的测量。采用双“悬臂梁+楔形滑块”的结构,当一个悬臂梁受位移作用处于变形状态时,另一个悬臂梁不变形并提供温度补偿功能。传感器处于零值测点状态时,两个悬臂梁处于零弯曲状态,且双梁互为温度补偿,消除了温度影响。通过性能测试实验证明,该传感器在±50的量程内,灵敏度为29.369 pm/mm,测量重复性好。制备出8个传感器应用于某市地铁的变形安全监测,从道床沉降、道床环缝、管片环缝3个方面开展了变形测量。在长期监测期间,传感器工作稳定,被测结构变形状态稳定,表明该传感器具有良好的测量性能,适用于长期的结构健康监测。  相似文献   
108.
Membrane decorated with biocides is an effective way to suppress biofilm growth. However, their immediate biocidal effect usually suffers from a significant decline due to the irreversible consumption of the biocides. Here, a smart nanofiltration membrane is reported with rechargeable antibacterial capability that is fabricated by a facile interfacial polymerization via 3-aminophenylboronic acid and trimesoyl chloride on a polysulfone substrate. Biocides bearing diol groups can be grafted onto the membrane surface under neutral/alkaline condition and then released from the surface under acidic environment, due to the pH-responsive feature of boronate ester complexes. The resultant membrane exhibits integrated properties of fast bacterial inactivating efficiency, rechargeable antibacterial capability, and impressive stability. In addition, the achieved membrane shows remarkable separation efficiency to dye/monovalent salt system. The successful fabrication of the membrane with rechargeable anti-bacterial property provides new insights into the development of pH-responsive and sustainable antibacterial membranes.  相似文献   
109.
Mg batteries as the most typical multivalent batteries are attracting increasing attention because of resource abundance, high volumetric energy density, and smooth plating/stripping of Mg anodes. However, current limitations for the progress of Mg batteries come from the lack of high voltage electrolytes and fast Mg‐insertable structure prototypes. In order to improve their energy or power density, hybrid systems combining Li‐driven cathode reaction with Mg anode process appear to be a potential solution by bypassing the aforementioned limitations. Here, FeS x (x = 1 or 2) is employed as conversion cathode with 2–4 electron transfers to achieve a maximum energy density close to 400 Wh kg?1, which is comparable with that of Li‐ion batteries but without serious dendrite growth and polysulphide dissolution. In situ formation of solid electrolyte interfaces on both sulfide and Mg electrodes is likely responsible for long‐life cycling and suppression of S‐species passivation at Mg anodes. Without any decoration on the cathode, electrolyte additive, or anode protection, a reversible capacity of more than 200 mAh g?1 is still preserved for Mg/FeS2 after 200 cycles.  相似文献   
110.
The glaciogenic Al Khlata Formation (Late Carboniferous – Early Permian) contains important reservoir and seal intervals in oil fields in southern Oman. Here we describe a 3D regional geological model of the Al Khlata Formation and the underlying Misfar Group in a 1750 km2 area in the Eastern Flank of the South Oman Salt Basin. The Misfar Group (Devonian‐Carboniferous?) was included in the model because it also contains glaciogenic facies in the study area. The 3D model is based on wireline logs from 42 wells, palynological zonation in 31 wells, cores from three wells, and a 2011 3D seismic dataset from which three horizons (top‐Huqf, top‐Rahab Shale and top‐Gharif) were interpreted throughout the study area. The combined Al Khlata and Misfar interval varies in thickness in the area from 20 to 730 m over relatively short distances. These large variations in thickness were due to the creation of accommodation in mini‐basins resulting from the removal of underlying Infracambrian salt at the basin margin. In places, some of the available accommodation was occupied by Cambrian sandstones of the Nimr Group and Haima Supergroup, influencing the location and thickness of the Al Khlata mini‐basins. These local depocentres vary in scale, shape and orientation relative to the present‐day salt edge: some are ovoid in plan‐view, others more linear and parallel to the salt edge, and one takes the form of a narrow graben almost perpendicular to the salt edge. By the Early Permian, towards the end of Al Khlata time, deposits become more blanket‐like and uniform, indicating an external or more regional control on base level. Four key lithofacies have been distinguished from wireline logs and were populated zone‐by‐zone through the geological model: sandstone (reservoir), shale (seal), and sandy and silty diamictite. Sandstones are most common towards the base of the Misfar – Al Khlata interval and shales towards the top. The Rahab Shale (Early Permian) at the top of the Al Khlata Formation forms an important seal for oil fields in South Oman, often in combination with seals in overlying intervals. The Rahab Shale was the first widespread seal to be deposited which may have trapped oil migrating from the South Oman Salt Basin during the Palaeozoic. The most common lithofacies in the Misfar – Al Khlata interval in the modelled area is diamictite (60%), which is normally considered to be a waste‐rock lithology. However thick silty diamictites of sufficient extent can seal hydrocarbon accumulations, and some sandy diamictites have the potential to be unconventional reservoir rocks. Even after 50 years of exploration and production of oil from the Al Khlata Formation, there remains potential for further discoveries and overlooked pay zones due to its heterogeneous character and the occurrence of intra‐formational seals.  相似文献   
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