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71.
In this paper, we address two important issues in the video concept detection problem: the insufficiency of labeled videos and the multiple labeling issue. Most existing solutions merely handle the two issues separately. We propose an integrated approach to handle them together, by presenting an effective transductive multi-label classification approach that simultaneously models the labeling consistency between the visually similar videos and the multi-label interdependence for each video. We compare the performance between the proposed approach and several representative transductive and supervised multi-label classification approaches for the video concept detection task over the widely used TRECVID data set. The comparative results demonstrate the superiority of the proposed approach.  相似文献   
72.
Ultra-thin membrane with nanoscale through hole has great potential in biomedical applications, where precise controllability of porosity, pore size and film thickness is urgently required. The present work proposed a cost-effective way to prepare the ultra-thin nanoporous film with a promising controllability. Monodispersed nanoparticle, rather than photoresist, is used as the sacrificial material for this new lift-off process. By releasing the particles, holes can be achieved with predeter-mined characters. A 110 nm-thick nanoporous aluminum film with well-controlled pore's diameter was successfully fabricated to validate the technique. The technique has wider process window and better applicability than other nanofabrication methods.  相似文献   
73.
Many important science and engineering applications, such as regulating the temperature distribution over a semiconductor wafer and controlling the noise from a photocopy machine, require interpreting distributed data and designing decentralized controllers for spatially distributed systems. Developing effective computational techniques for representing and reasoning about these systems, which are usually modeled with partial differential equations (PDEs), is one of the major challenge problems for qualitative and spatial reasoning research.

This paper introduces a novel approach to decentralized control design, influence-based model decomposition, and applies it in the context of thermal regulation. Influence-based model decomposition uses a decentralized model, called an influence graph, as a key data abstraction representing influences of controls on distributed physical fields. It serves as the basis for novel algorithms for control placement and parameter design for distributed systems with large numbers of coupled variables. These algorithms exploit physical knowledge of locality, linear superposability, and continuity, encapsulated in influence graphs representing dependencies of field nodes on control nodes. The control placement design algorithms utilize influence graphs to decompose a problem domain so as to decouple the resulting regions. The decentralized control parameter optimization algorithms utilize influence graphs to efficiently evaluate thermal fields and to explicitly trade off computation, communication, and control quality. By leveraging the physical knowledge encapsulated in influence graphs, these control design algorithms are more efficient than standard techniques, and produce designs explainable in terms of problem structures.  相似文献   

74.
Tensile tests show that ferroelastic loops always occur at 100–150 K, 200–250 K and room temperature in the Y1–xPrxBa2Cu3Oy samples withx=0 and 0.1 for whichT c is 92 K and 82.5 K respectively, and the shape memory effect is always observed in the compact sample near 130 K, just similar to that of thermal elastic martensitic alloys. The loss fraction (W/W) which is proportional to the area of ferroelastic loop as a function of temperature shows that there always exist static hysteresis (W/W) peaks at 130 K and 110 K which are attributed to the phaselike transition (PLT) characterized by the jump of lattice parameters. No ferroelastic loops and shape memory effect are observed in the range of 100 K to 150 K for the lowerT c samples withx=0.3, 0.4 and 0.6.  相似文献   
75.
In the construction of the filling gob-side entry retaining in a lane, we utilize the self-slide natural phenomenon of a falling gangue in an inclined coal seam goaf. First, we put the falling gangue of goaf above the laneway and made it the main filling material by adopting the measurement of flexible supporting system combined with those of rigid supporting system. Then we made the filling material gunited and solidified to maintain the filling goal of the gob-side entry retaining beside the lane. Considering the law of energy conservation and law of pressure distribution for retaining the active and static soil of the wall, we analyzed the reliability of a gangue blocking facilities and the stability of the filling material in the lane. We analyze the figures to see the stability. The result shows that the gangue block supporting system is reliable, and has been successfully practically applied.  相似文献   
76.
赵立坤  郭书英 《中国水利》2012,(14):25-28,38
水利信息化是实现水利现代化的基础和重要标志。以水管理对象为基础,利用现代信息技术构造数字流域,集中管理流域内的水事问题,是实现流域现代化管理的有效途径。从数字流域体系架构、水管理对象构造及全息化描述、基础平台构建、业务系统的构件化开发、数字功能流域等方面详细介绍了基于水管理对象的数字流域构造技术方法。  相似文献   
77.
This paper compared the degradation efficiency of sludge organic matters and electric-production by two typical microbial fuel cells——dual-chamber microbial fuel cell(DMFC)and single chamber air cathode microbial fuel cell(SAMFC),and the variations of sludge protein,polysaccharide and ammonia nitrogen within the systems were also investigated.The results showed that the concentration of sludge soluble chemical oxygen demand,protein and carbohydrate of DMFC are higher than these of SAMFC during the systems operation,while DMFC can achieve a better ammonia nitrogen removal than SAMFC.Under the same operation condition,the stable voltage output of DMFC and SAMFC is 0.61 V and 0.37 V;the maximum power density of DMFC and SAMFC is 2.79 W/m3and 1.25 W/m3;TCOD removal efficiency of DMFC and SAMFC is 34.14%and 28.63%for 12 d,respectively.Meanwhile,DMFC has a higher coulomb efficiency than SAMFC,but both are less than5%.The results showed that DMFC present a better performance on sludge degradation and electric-production.  相似文献   
78.
79.
ZnO thin films have been deposited by pulsed laser deposition (PLD) and ultrasonic spray pyrolysis (USP) method, respectively. X-ray diffraction and transmission electron microscopy characterizations indicate that ZnO film grown by PLD exhibits better crystallinity than that grown by USP. Photoluminescence spectra show that the near-band edge ultraviolet emission of film grown by PLD is narrower and shifts to higher energy, compared with that of film grown by USP. In the visible range, ZnO film grown by PLD exhibits four local level emission centered at 470 nm, 486 nm, 544 nm, and 613 nm, respectively, while the film grown by USP only presents a weak broad band emission centered at 502 nm. Hall measurement shows higher carrier density and lower hall mobility in ZnO film grown by PLD than that in film grown by USP. The higher density of intrinsic defects as well as higher crystallintiy is considered to account for the difference of photoluminescence in ZnO film grown by PLD with that in film grown by USP.  相似文献   
80.
介绍PowerPoint2003中内、外部声音的运用与控制技术.  相似文献   
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