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321.
Real-time traffic parameter extraction using entropy 总被引:3,自引:0,他引:3
Hsu W.-L. Liao H.-Y.M. Jeng B.-S. Fan K.-C. 《Vision, Image and Signal Processing, IEE Proceedings -》2004,151(3):194-202
A vision-based traffic monitoring system that can perform real-time traffic parameter extraction is proposed. The entropy measurement, which is commonly adopted as an important feature to describe the degree of disorder in thermodynamics, is used as an underlying feature in this work. Based on an entropy measurement, a number of important traffic parameters, such as traffic flow, space mean speed and traffic queue, can be determined in real time. The experimental results clearly show that the proposed system is highly effective. 相似文献
322.
This paper presents a novel method in which an oxide film is used to facilitate the thermosonic wire bonding of gold wire
onto copper pads. A cuprous oxide film is generated by controlling the pH values of the chemical solution. Compared to cupric
oxide films, the cuprous oxide film is denser and more brittle and therefore facilitates the bonding process without the need
for the elaborate procedures and equipment required by more conventional wire bonding methods. 相似文献
323.
D. C. P. Jiang Y. J. Jeng A. N. Konovalov A. V. Mironov V. K. Popov Yo. Yu. Chen Yu.-L. Cheng R. Shafikova 《Bulletin of the Russian Academy of Sciences: Physics》2016,80(4):362-366
The formation of porous matrix structures (scaffolds) from biocompatible polymers and their composites with finely dispersed hydroxyapatite via air pressure–aided 3D printing and digital light processing (DLP) is studied. A triblock copolymer (polyethylene glycol/poly-ε-caprolactone/polyethylene glycol) and polyethylene glycol diacrylate served as raw polymer materials. The internal structure and surface morphology of the resulting scaffolds and the correspondence of their architectonics to the initial 3D virtual models are analyzed by means of optical and scanning electron microscopy. 相似文献
324.
Yi-Jie Jiang Jiiang-Huei Jeng Pin-Hsuan Wu Hsiu-Wen Chien 《Macromolecular bioscience》2023,23(3):2200368
This study focuses on the preparation of stretchable zwitterionic poly(sulfobetaine methacrylate) (PSBMA) hydrogels. To address the weak mechanical properties of chemically crosslinked PSBMA hydrogels, a physical crosslinking method utilizing hydrophobic interactions to crosslink hydrogels to approach tough properties is developed. Here, sodium dodecyl sulfate (SDS)-based micelle is used as a physical crosslinker to prepare physically crosslinked PSBMA (PSBMAphy) hydrogels, and ethylene glycol dimethylacrylate (EGDMA) is used to prepare a control group of chemically crosslinked PSBMA (PSBMAchem) hydrogels. The mechanical properties of the two hydrogels are compared, and PSBMAphy hydrogels exhibit greater flexibility than the PSBMAchem hydrogels. When the PSBMAphy hydrogels are subjected to external forces, the micelles act as dynamic crosslinking sites, allowing the stress to disperse and prevent the hydrogel from breaking. In addition, the PSBMAphy hydrogels have nearly 100% self-healing properties within 2.5 min. The PSBMAphy hydrogels exhibit usable adhesive properties to porcine skin and subcutis. MTT and hemolysis tests show that the PSBMAphy hydrogels have excellent biocompatibility and hemocompatibility. This study proposes that the multifunctional PSBMAphy hydrogels with micelles will be potential to carry drugs for use in drug delivery systems in the future. 相似文献
325.
Immobilized fullerene C60/anti‐insulin antibody was prepared and applied in shear horizontal surface acoustic wave (SH‐SAW) immunosensors to detect insulin in aqueous solutions. The immobilizations of anti‐insulin onto fullerene were studied through a C60/PVC coated SH‐SAW sensor system in liquid. The partially irreversible frequency response for an anti‐insulin antibody was observed by the desorption study, which implied that fullerene could chemically react with anti‐insulin. C60/anti‐insulin coating materials were successfully prepared and identified with an FTIR spectrometer. The C60/anti‐insulin coated SH‐SAW immunosensors were developed and applied for detection of insulin in aqueous solutions. Within the range of normal human insulin concentration, the SH‐SAW immunosensors immobilized with C60/anti‐insulin exhibited linear frequency responses to the concentration of insulin with a sensitivity of 130 Hz/pM. The SH‐SAW immunosensor immobilized with C60/anti‐insulin showed a detection limit of 0.58 pM for insulin in aqueous solution. The interference of various common bio‐species in human blood, e.g. urea, ascorbic acid, tyrosine, and metal ions, to the SH‐SAW immunosensor immobilized with C60/anti‐insulin for insulin was investigated. These common bio‐species interferences showed nearly no interference to the SAW immunosensors coated with C60/anti‐insulin. The reproducibility of the SH‐SAW immunosensor immobilized with C60/anti‐insulin for insulin was also investigated and is discussed. 相似文献
326.
Hsun‐Lien Lin Tsung‐Yi Chao Yeng‐Fong Shih Shenghong A. Dai Wen‐Chiung Su Ru‐Jong Jeng 《先进技术聚合物》2008,19(8):984-992
A series of thermally stable organic/inorganic second‐order nonlinear optical (NLO) composites via sequential self‐repetitive reaction (SSRR) and sol–gel process has been developed. This SSRR is based on carbodiimide (CDI) chemistry. The difunctional azo chromophores (2,4‐diamino‐4′‐(4‐ nitrophenyl‐diazenyl)azobenzene (DNDA)) was reacted with excessive amount of 4, 4′‐methylene‐ diphenylisocyanate (MDI) to form poly‐CDI, and subsequently trimellitic anhydride (TMA) was added to obtain poly(N‐acylurea). The organic/inorganic composites containing prepolymer of phenyltriethoxysilane (PTEOS) and poly(N‐acylurea) in different weight ratios (10:90, 30:70, 50:50, 70:30, 90:10 wt%) were prepared, respectively. The moderate glass transition temperature (Tg) characteristic of the poly(N‐acylurea) allows the NLO‐active polymer to achieve high poling efficiency. After in situ poling and curing process, the Tgs of the composites were elevated, and higher than that of the pristine poly(amide–imide) sample. Electro‐optical (EO) coefficients (r33) of about 5.5 ~ 18.0 pm/V at 830 nm were obtained. Excellent temporal stability at 100°C, and waveguide characteristics (3.1–4.2 dB/cm at 830 nm) were also obtained for these composites. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
327.
High conducting polyaniline films were readily prepared by in situ chemical oxidative polymerization/deposition of aniline in the presence of a very small amount of organic additive such as phenol. The conductivity of a thin ( approximately 150 nm) polyaniline film synthesized in the presence of 0.01 wt % of phenol ( r-PANI) is an order of magnitude higher (as well as better conducting homogeneity) than that of a film (PANI) obtained from the conventional method without an additive. r-PANI also has better adhesion and electrochemical stability/reversibility, more transparency in the visible-light region, and faster/easier doping/dedoping response compared to PANI. The function of phenol molecule is to avoid the formation of the inter- and/or intrachain hydrogen bonding during the growth of the polyaniline chains. The deaggregation/reducing intrachain hydrogen bonding of polyaniline chains by phenol molecules was revealed with IR, SAXS, and SEM data. All these data supported that phenol does assist the deaggregation of polyaniline chains during the growth of polymer chains or nanorods. 相似文献
328.
329.
330.
Tung‐Shih Su Wei‐Lun Jeng Jeng‐Yi Huang Wen‐Shyong Hsieh 《International Journal of Communication Systems》2010,23(4):507-527
In ad hoc wireless networks, most data are delivered by multi‐hop routing (hop by hop). This approach may cause long delay and a high routing overhead regardless of which routing protocol is used. To mitigate this inherent characteristic, this work presents a novel ad hoc network structure that adopts dual‐card‐mode, self‐organization with specific IP naming and channel assignment to form a hierarchical star graph ad hoc network (HSG‐ad hoc). This network not only expedites data transmission but also eliminates the route discovery procedure during data transmission. Therefore, the overall network reliability and stability are significantly improved. Simulation results show that the proposed approach achieves substantial improvements over DSDV, AODV, and DSR in terms of average end‐to‐end delay, throughput, and packet delivery ratio. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献