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101.
Multimedia Tools and Applications - In digital pathology, image similarity algorithms are used to find cancer in tissue cells from medical images. However, it is very difficult to apply image...  相似文献   
102.
A new protecting layer, a LaF3‐coated MgO layer, in color AC‐plasma‐display panels (PDPs) was studied in order to overcome the weakness of the conventional single MgO protecting layer. The material characteristics of the new layer were examined by using variations in the deposition process. The display characteristics were also examined by implementing their processes to actual PDPs. It was demonstrated that this method is effective in lowering the firing and sustaining voltages of PDPs and enhancing the brightness of the panel as well.  相似文献   
103.
Abstract— In an attempt to reduce materials and processing costs of ACPDPs, aluminum fence electrodes were prepared on soda‐lime glass substrates by chemically etching aluminum foil bonded directly onto the substrate via an anodic‐bonding process. Several different fence‐electrode patterns were designed and coated either with a glass dielectric layer or with an anodic aluminum oxide layer. Firing voltages, operation margin, luminance, and luminous efficiency of such test panels were evaluated. The results indicated that the performance of test panels with aluminum fence electrodes is comparable with conventional test panels with ITO/Ag electrodes, demonstrating the possibility of a dramatic reduction in the costs of ACPDPs.  相似文献   
104.
Embedded systems such as PVR, set-top box, HDTV put unique demand on I/O subsystem design. Underlying software, particularly file system, needs to be elaborately designed so that it can meet tight constraints of consumer electronics platform: performance, price, reliability, and etc. In this work, we develop state-of-art file system elaborately tailored for A/V workload. There are two design objectives in our file system: performance and support for logical level abstraction. For performance, we develop a number of novel features: extent based allocation, single level file structure with block index augmentation scheme, aggressive free block allocation to minimize disk fragmentation, elaborate file system meta data layout, separation of name space data and file data and etc. HERMES enables the user to view file as a collection of semantic units (frame or audio samples). HERMES file system encompasses most of state-of-the-art file system technologies published in preceding works. Via extensive physical experiment, we verify that HERMES file system successfully addresses the original issues: good scalability, predictable I/O latency (minimizing variability in I/O latency), efficient disk head movement and etc. This is the result of harmonious effort of large I/O size, aggressive free block allocation algorithm, data block placement strategy, file organization, layout of HERMES file system and etc. The result of performance experiments indicate that HERMES file system prototype successfully meets the file system constraints for high volume and high bandwidth multimedia application. HERMES file system exhibits superior performance to EXT2 file system (Linux) and XFS file system (SGI).
Youjip WonEmail:
  相似文献   
105.
Jeremic A  Jin Cho W  Jena BP 《Ultramicroscopy》2006,106(8-9):674-677
Secretion is one of the most fundamental cellular processes. Porosomes have been demonstrated as the universal secretory machinery in cells. Earlier studies determine the presence of a number of proteins in porosomes, among them the N- and P/Q-type calcium channels, actin, syntaxin-1, synaptotagmin-1, vimentin, the N-ethylmaleimide-sensitive factor (NSF), the chloride channel CLC-3, and the alpha subunit of the heterotrimeric GTP-binding protein G(o). Studies demonstrate that t-SNAREs localize at the base of porosomes, and directly interact with calcium channels. In the present study, we demonstrate that Syntaxin-1 co-localizes with cholesterol in solubilized synaptosomal membrane preparations. Depletion of cholesterol, results in the dissociation of both Syntaxin-1 and N-type calcium channel from neuronal porosomes. Thus, cholesterol participates as an integral component of the neuronal porosome complex, and is required for its stability.  相似文献   
106.
Homogeneous and nano-sized BPNT [(Ba1-xPbx)Nd2Ti5O14] powders were prepared under various hydrothermal conditions. Crystallinity and homogeneity of the synthetic powders were investigated. The microwave dielectric properties of the filters prepared with hydrothermal powders were compared with those of the filters prepared with conventional powders. The microwave dielectric properties of the filter prepared with the hydrothermal powders were also better than those of the filter manufactured with the conventional powders. The dielectric constant, quality constant and temperature coefficient of resonance frequency of hydrothermally prepared filter under optimum condition and measured at 3.5 GHz around were about 93, 6067 and 0 ppm/°C, respectively.  相似文献   
107.
Traditionally, the yard-planning problem has been considered to be the assignment of yard spaces to arriving vessels in practices of container terminals. This study proposes an integrated decision-making framework for the yard-planning that simultaneously considers various resources such as storage space, yard cranes, and traffic area in container terminals for planning. The decision-making framework in this study is based on a mathematical model, which supports intelligent yard-planning activities considering work-loads on various related resources. Further, it is shown that the decision-making framework for the yard-planning can be extended to that for simultaneous decisions on yard plans and handling capacity of yard cranes per block. A heuristic algorithm is also proposed in order to reduce the computational time for planning. Numerical experiments are conducted to validate the models and algorithms proposed in this study.  相似文献   
108.
Removal efficiencies of endocrine disrupting chemicals (EDCs), bisphenol A and nonylphenol, during various types of water treatment processes were evaluated extensively using laboratory- and pilot-scale experiments. The specific processes of interest were coagulation/flocculation sedimentation/filtration (conventional water treatment process), powdered activated carbon (PAC), granular activated carbon (GAC), ozonation and chlorination. Batch sorption tests, coagulation tests, and ozone oxidation tests were also performed at higher concentrations with 14 EDCs including bisphenol A. The conventional water treatment process had very low removal efficiencies (0 to 7%) for all the EDCs except DEHP, DBP and DEP that were removed by 53%, 49%, and 46%, respectively. Ozonation at 1 mgO3/ L removed 60% of bisphenol A and 89% of nonylphenol, while chlorination at 1 mg/L removed 58% and 5%, respectively. When ozone and chlorine doses were 4 and 5 mg/L, respectively, both EDCs were not detected. PAC removal efficiencies ranged from 15% to 40% at 3 to 10 mg/L of PAC with a contact time of 15 minutes. In the high concentration batch sorption tests, EDC removal efficiencies by PAC were closely related to octanol-water partition coefficient (Kow). GAC adsorption was very effective water treatment process. The type and service time of GAC did not affect EDC removal efficiencies. The combination of ozonation and GAC in series appears to remove EDCs effectively to safe levels while conventional water treatment could not.  相似文献   
109.
Nd-doped bismuth titanate Bi4 − x Nd x Ti3O12 ceramics (x = 0–1.0) were prepared by the solid state reaction method. The temperature dependence of the dielectric dispersion and ferroelectric properties were investigated. With the increase of the Nd substitution for Bi ion, the Curie temperature decreased and the corresponding dielectric constant peak broadened. In addition, the strong low-frequency dielectric dispersions were exhibited. The Nd doping decreases the temperature dependence of the ac conductivity and increases the temperature dependence of the remanent polarization, which is caused by the induced polarization by defects, such as bismuth and oxygen vacancies.  相似文献   
110.
PZT thin films and interlayers were fabricated by the radio frequency (r.f.) Magnetron-sputtering from the Pb1.1Zr0.53Ti0.47O3, PbO and TiO2 target. As a result of the XPS depth profile analysis, we can confirm that the substrate temperature affects the oxidation condition of each element of interlayers and the PZT film. Compared to the PZT/Pt structure, the dielectric and pyroelectric properties of PZT thin films inserted by interlayers were measured to a relatively high value. In particular, the PZT/PbO structure had the highest pyroelectric properties (P = 189.4 μC/cm2K; F D = 12.7×10−6 Pa−1/2; F V = 0.018 m2/C).  相似文献   
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