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131.
设计了一种小型水下连续光成像系统,主要用于小型水下载具或潜水员提高水下视觉能力。该系统以多片大功率LED为光源,以CCD为接收器。为改善图像质量,在分析连续光照明条件下水下图像特点的基础上,使用了一种基于模型法的图像处理算法,并在以DM642为核心的嵌入式图像处理平台上实现。系统进行了室内水池和外场实验,结果表明:针对黑白条纹靶板,系统的极限探测距离达到2.3倍衰减长度以上;图像处理算法能较好适应多种背景和系统结构变化,有效提高图像对比度、突出目标细节。 相似文献
132.
介绍了在激光水下成像系统中,应用SD卡存储图像数据的具体方案及实施细节。包括SD卡与DSP处理器的电路连接,SPI总线的配置方法,系统软件层次结构的分析,SD卡的操作以及文件系统的移植及应用。该方案在水下成像系统的设计实现中具有应用价值。 相似文献
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A new monomer, 1,5‐bis(p‐dimethylaminophenylimino)naphthalene, was prepared through Schiff‐base condensation reaction of 1,5‐diaminonaphthalene and 4‐(dimethylamino)benzaldehyde in the presence of ethanol. A series of aromatic polyimides bearing naphthalene and ? CH?N? groups were synthesized from the diamine with five kinds of commercial dianhydrides via a conventional one‐stage process. The resulting naphthalene based polyimides (NBPs) showed good solubilities in N‐methyl‐2‐pyrrolidone and m‐cresol. NBPs had glass‐transition temperatures at 139–174°C and 10% weightloss temperatures above 430 °C in nitrogen atmospheres. Excellent properties of NBPs are attributed to the incorporation of the naphthalene and ? CH?N? group in 1,5‐bis(p‐dimethylaminophenylimino)naphthalene. Moreover, chemically prepared polyimides were used for immobilization of glucose oxidase (GOx). The amperometric responses of the NBPs‐GOx‐Pt electrodes toward glucose were examined at a potential of 0.7 V in PBS solution by means of time‐base (TB) technique. Results show that NBPs bearing ? O? group membrane (PI‐3) has many advantages in the immobilization of glucose oxidase because of its strong adherence to electrode surface and chemical stability and selectivity. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
135.
Yong‐Sung Eom Kwang‐Seong Choi Seok‐Hwan Moon Jun‐Hee Park Jong‐Hyun Lee Jong‐Tae Moon 《ETRI Journal》2011,33(6):864-870
As an isotropic conductive adhesive, that is, a hybrid Cu paste composed of Cu powder, solder powder, and a fluxing resin system, has been quantitatively characterized. The mechanism of an electrical connection based on a novel concept of electrical conduction is experimentally characterized using an analysis of a differential scanning calorimeter and scanning electron microscope energy‐dispersive X‐ray spectroscopy. The oxide on the metal surface is sufficiently removed with an increase in temperature, and intermetallic compounds between the Cu and melted solder are simultaneously generated, leading to an electrical connection. The reliability of the hybrid Cu paste is experimentally identified and compared with existing Ag paste. As an example of a practical application, the hybrid Cu paste is used for LED packaging, and its electrical and thermal performances are compared with the commercialized Ag paste. In the present research, it is proved that, except the optical function, the electrical and thermal performances are similar to pre‐existing Ag paste. The hybrid Cu paste could be used as an isotropic conductive adhesive due to its low production cost. 相似文献
136.
Hee Jin Jeong Hae Deuk Jeong Ho Young Kim Jun Suk Kim Seung Yol Jeong Joong Tark Han Dae Suk Bang Geon‐Woong Lee 《Advanced functional materials》2011,21(8):1526-1532
The fabrication of a flexible field‐emission device (FED) using single‐walled carbon nanotube (SWNT) network films as the conducting electrodes (anode and cathode) and thin multi‐walled CNT/TEOS hybrid films as the emitters is reported. P‐type doping with gold ions and passivation with tetraethylorthosilicate (TEOS) made the SWNT network film highly conductive and environmentally stable, and hence a good alternative to conventional indium tin oxide electrodes. CNT/TEOS hybrid emitters showed high current density, low turn‐on field, and long‐term emission stability, compared with CNT emitters; these characteristics can be attributed to the TEOS sol, acting both as a protective layer surrounding the nanotube tip, and as an adhesive layer enhancing the nanotube adhesion to the substrate. All‐CNT‐based flexible FEDs fabricated by this approach showed high flexibility in field emission characteristics and extremely bright electron emission patterns. 相似文献
137.
厚膜导体是厚膜混合集成电路中的一个重要组成部分,在电路中起有源器件的互连线、多层布线、电容器电极、外贴元器件的引线焊区、电阻器端头材料、低阻值电阻器、厚膜微带等作用.在厚膜混合集成电路的生产过程中,为了评价成膜基片的性能及焊接的效果,在做剪切强度测试时,经常会遇到焊盘脱落现象,这给厚膜电路的产品质量带来很大隐患.文章通... 相似文献
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Aoyagi Y Kuroda M Asada S Bujo H Tanaka S Konno S Tanio M Ishii I Aso M Saito Y 《Experimental & molecular medicine》2011,43(3):161-167
The development of clinically applicable scaffolds is important for the application of cell transplantation in various human diseases. The aims of this study are to evaluate fibrin glue in a novel protein replacement therapy using proliferative adipocytes and to develop a mouse model system to monitor the delivery of the transgene product into the blood and the fate of the transduced cells after transplantation. Proliferative adipocytes from mouse adipose tissue were transduced by a retroviral vector harboring the human lecithin-cholesterol acyltransferase (lcat) gene, and were subcutaneously transplanted into mice combined with fibrin glue. The lcat gene transduction efficiency and the subsequent secretion of the product in mouse adipocytes were enhanced using a protamine concentration of 500 μg/ml. Adipogenesis induction did not significantly affect the lcat gene-transduced cell survival after transplantation. Immunohistochemistry showed the ectopic enzyme production to persist for 28 days in the subcutaneously transplanted gene- transduced adipocytes. The increased viability of transplanted cells with fibrin glue was accompanied with the decrease in apoptotic cell death. The immunodetectable serum LCAT levels in mice implanted with the fibrin glue were comparable with those observed in mice implanted with Matrigel, indicating that the transplanted lcat gene-transduced adipocytes survived and functioned in the transplanted spaces with fibrin glue as well as with Matrigel for 28 days. Thus, this in vivo system using fibrin is expected to serve as a good model to further improve the transplanted cell/scaffold conditions for the stable and durable cell-based replacement of defective proteins in patients with LCAT deficiency. 相似文献