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1.
Visualization software for three dimensional digital brain atlases present many challenges in design and implementation. These challenges include the design of an effective human interface, management of large data sets, display speed when slicing the data set for viewing/browsing, and the display of delineated volumes of interest (VOI). We present a software design, implementation and storage architecture that addresses these issues, allowing the user to navigate through a reconstructed volume quickly and smoothly, with an easy-to-use human interface. The software (macostat, for use with Macintosh OS) allows the user to rapidly display slices of the digital atlas at any arbitrary slicing angle, complete with delineated VOIs. The VOIs can be assigned colors of the user's choosing. The entire atlas, or selected portions, may be resliced with slices stored as individual image files, complete with delineations. These delineations may be transferred to corresponding sections of experimental materials using our analysis program (brain). The software may be obtained from the laboratory's web site: http://www.neuroterrain.org  相似文献   
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对于有线电视运营商来说,为满足当今快速增长的语音和高速数据业务的需要.双向通信系统中的“上行”回传就显得尤为重要。最初的“广播”网中,回传通道只局限于对覆盖用户的状态监控和基本的机顶盒控制,随着时间的推进,情况逐步发生变化:先是受限机顶盒交互的QPSK调制,然后是DOCSIS 1.x的16QAM调制,再到DOCSIS2.0和DOCSIS3.0的64QAM调制。  相似文献   
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In this paper, we discuss an integrated process planning and scheduling problem in large-scale flexible job shops (FJSs). We assume that products can be manufactured in different ways, i.e. using different bills of materials (BOM) and routes for the same product. The total weighted tardiness is the performance measure of interest. A Mixed Integer Programming formulation is provided for the researched problem. Because of the NP-hardness of the investigated problem, an iterative scheme is designed that is based on variable neighbourhood search (VNS) on the process planning level. Appropriate neighbourhood structures for VNS are proposed. Because the evaluation of each move within VNS requires the solution of a large-scale FJS scheduling problem instance, efficient heuristics based on local search from previous research are considered on the scheduling level. Extensive computational experiments based on new randomly generated problem instances are conducted. In addition, a parallel version of the VNS is investigated within the computational experiments. The proposed iterative scheme is benchmarked against a genetic algorithm (GA) from the literature that simultaneously considers process planning and scheduling for the special case where a single BOM is available for each product. It turns out that the new iterative scheme outperforms the GA and a memetic algorithm based on the GA. It is able to solve even large-size problem instances in reasonable amount of time.  相似文献   
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Innovative amperometric biosensors for monitoring the level of wastewater pollution have been constructed on the surface of the gold planar electrodes C220AT “DropSens” by using the organic–inorganic ureasil‐based composites as host matrixes and immobilized commercial laccase from Trametes versicolor . It was found that the biosensor based on the ureasil–chalcogenide glass composite is characterized by a very high sensitivity (67,540 А M?1 m?2) that is 38.3 times higher than for pure ureasil (the sensitivity of the bioelectrode was calculated as 1762 А M?1 m?2). On the other hand, application of the ureasil–chalcogenide glass composite with incorporated silver nanoparticles (NPs) synthesized by high‐dose (1.0 × 1017 Ag+/cm2) 30 keV Ag+ ion implantation results in decreasing the biosensor sensitivity up to 2390 times (the sensitivity of the bioelectrode was 28.3 А M?1 m?2). The role of additives (chalcogenide glass and silver NPs) in the ureasil matrix on the biofunctionality of the biosensors produced is considered. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45278.  相似文献   
6.
In the present work, the influence of Cr and Ca co-additives on the phase formation under conditions emulated the real sintering process of Cr4+:YAG ceramics is studied. The XRD analysis of the treated samples revealed the difference in formation rates of intermediate phases between the samples with and without the Cr2O3 additive. The formation of intermediate phases in the solid-state reaction between Y2O3 and Al2O3 is observed to shift toward higher temperatures (ie, toward the stage of fast shrinkage) if the mixture of Cr2O3 and CaO is added. The reason for such shift is the appearance of new intermediate, which contains Cr4+ ions in perovskite structure, as has been established by optical absorption and luminescent investigations. It is found that the Cr,Ca:YAG ceramics prepared by vacuum solid state reaction sintering at 1750°C, 10 hours possesses better optical transparency than Ca:YAG ceramics prepared under the same conditions.  相似文献   
7.
The formation of TiCxNy coatings on titanium alloys through thermochemical treatment of graphite in nitrogen was investigated in this study. The presence of oxygen in saturating media was found to lower the nitrocarburizing temperature from 1,100°C to 850°C. Two methods to accumulate oxygen in a saturating medium have been proposed: using oxygen-containing nitrogen or oxygensaturated graphite. The sequence of stages of carbonitride formation in the Ti-C-N-O system is explained in this paper.  相似文献   
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Illegal logging is a major environmental and economic problem, and exceeds in some countries the amounts of legally harvested timber. In Eastern Europe and the former Soviet Union, illegal logging increased and reforestation on abandoned farmland was widespread after the breakdown of socialism, and the region's forest cover trends remain overall largely unclear. Our goal here was to map forest cover change and to assess the extent of illegal logging and reforestation in the Ukrainian Carpathians. We used Landsat TM/ETM+ images and Support Vector Machines (SVM) to derive forest change trajectories between 1988 and 2007 for the entire Ukrainian Carpathians. We calculated logging and reforestation rates, and compared Landsat-based forest trends to official statistics and inventory maps. Our classification resulted in reliable forest/non-forest maps (overall accuracies between 97.1%-98.01%) and high clear cut detection rates (on average 89.4%). Forest cover change was widespread in the Ukrainian Carpathians between 1988 and 2007. We found forest cover increase in peripheral areas, forest loss in the interior Carpathians, and increased logging in remote areas. Overall, our results suggest that unsustainable forest use from socialist times likely persisted in the post-socialist period, resulting in a continued loss of older forests and forest fragmentation. Landsat-based forest trends differed substantially from official forest resource statistics. Illegal logging appears to have been at least as extensive as documented logging during the early 1990s and so-called sanitary clear-cuts represent a major loophole for overharvesting and logging in restricted areas. Reforestation and illegal logging are frequently not accounted for in forest resource statistics, highlighting limitations of these data. Combating illegal logging and transitioning towards sustainable forestry requires better monitoring and up-to-date accounting of forest resources, in the Carpathians and elsewhere in Eastern Europe, and remote sensing can be a key technology to achieve these goals.  相似文献   
10.
Magnetite nanoparticles (Fe3O4 NPs) with peroxide-containing polymer shell have been synthesized using the method of coprecipitation from the mixture solutions of Fe (II) and Fe (III) salts in the presence of peroxide-containing copolymer (PCC). Polymer shell presence has been proved by elemental and complex thermal analysis. Synthesized Fe3O4 NPs possess superparamagnetic properties. Their specific saturation magnetization decreases gradually from 65 to 54 A·m2·kg−1 with increasing PCC concentration owing to the surface spin pinning effect caused by a polymer shell. The average sizes of Fe3O4 NPs estimated from the data of XRD analysis and magnetic measurements are in the range of 9–12 nm. The NP sizes determined by the DLS method lie in the range of 150–270 nm; this result is significantly larger than the sizes estimated by the two aforementioned methods evidencing a tendency for Fe3O4 NPs toward self-association. Cross-linked composite films based on polyvinyl alcohol have been obtained via radical curing initiated by the PCC shell of nanoparticles. The resulting composite films are magnetically sensitive films with rather high physico-mechanical properties (tensile strength reaches 48–67 MPa and relative elongation – 4%–21% depending on cross-linking degree), a priori non-toxic and biocompatible, which makes them promising materials for various applications.  相似文献   
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