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991.
Multi-way set enumeration in weight tensors 总被引:2,自引:0,他引:2
The analysis of n-ary relations receives attention in many different fields, for instance biology, web mining, and social studies. In the basic
setting, there are n sets of instances, and each observation associates n instances, one from each set. A common approach to explore these n-way data is the search for n-set patterns, the n-way equivalent of itemsets. More precisely, an n-set pattern consists of specific subsets of the n instance sets such that all possible associations between the corresponding instances are observed in the data. In contrast,
traditional itemset mining approaches consider only two-way data, namely items versus transactions. The n-set patterns provide a higher-level view of the data, revealing associative relationships between groups of instances. Here,
we generalize this approach in two respects. First, we tolerate missing observations to a certain degree, that means we are
also interested in n-sets where most (although not all) of the possible associations have been recorded in the data. Second, we take association
weights into account. In fact, we propose a method to enumerate all n-sets that satisfy a minimum threshold with respect to the average association weight. Technically, we solve the enumeration
task using a reverse search strategy, which allows for effective pruning of the search space. In addition, our algorithm provides
a ranking of the solutions and can consider further constraints. We show experimental results on artificial and real-world
datasets from different domains. 相似文献
992.
F. Paulo Kemper Koji A. O. Suzuki James R. Morrison 《Journal of Intelligent and Robotic Systems》2011,61(1-4):369-397
A key requirement for the complete autonomy of an unmanned aerial vehicle (UAV) is the replenishment of its energy source and other consumables. Such processes are typically overseen and conducted by a human operator, may be time consuming and effectively reduce the operating range of the system. To satisfy the requirements of UAV customers such as military surveillance networks, that seek faster, broader and more fully autonomous systems, and hobbyists, who seek to avoid the hassle associated with changing the fuel source, we develop automated energy recharging systems. Focusing on battery operated remote control helicopters, we employ the Axiomatic Design methodology to develop design concepts of platforms to act as automatic service stations. We propose three station designs for refilling platforms and one concept for battery exchange platforms. In addition, we analyze the economic feasibility of automatic consumable replenishment stations, consider two types of station (container refilling and container exchange) and discuss the application of these systems. Refilling platforms better suit low coverage unmanned aerial systems (UAS) while exchange stations allow high coverage with fewer UAVs. 相似文献
993.
Miyoshi Ayama Takashi Fuseda Toshiya Hamano Tomoharu Ishikawa 《Journal of the Society for Information Display》2016,24(2):74-84
The effect of blue primary color on image quality was studied. We used the KANSEI evaluation method, and for experiments, we used Semantic Differential method. First, four different blue primaries of 430, 450, 470, and 480 nm with full brightness of Lmax equal 60 cd/m2 were tested. The same experiment was performed for 450, 470, and 480 nm at Lmax of 170 cd/m2. The results for the four primaries show that 450‐ and 470‐nm blue primaries are the best. Then 430 nm was next, and 480‐nm blue primary shows the worst performance. In the tests of three primaries, the 470 nm shows the highest scores for bluish test images. Results are compared with color naming data in the entire chromaticity diagram. 相似文献
994.
Tradeoffs between quantization and packet loss in networked control of linear systems 总被引:1,自引:0,他引:1
In this paper, we consider to derive the coarsest memoryless quantizer which can stabilize a single-input discrete-time linear time-invariant system with stochastic packet loss in the sense of stochastic quadratic stability. We show that the upper bound of the coarseness is strictly given by the packet loss probability and the unstable poles of the plants. We furthermore deal with permissible dead-zone width around the origin of the quantizers and time-varying finite quantizers in order to realize control using finite quantization steps. 相似文献
995.
Yuji Matsumoto Hozumi Tanaka Hideki Hirakawa Hideo Miyoshi Hideki Yasukawa 《New Generation Computing》1983,1(2):145-158
A parser based on logic programming language (DCG) has very useful features; perspicuity, power, generality and so on. However, it does have some drawbacks in which it cannot deal with CFG with left recursive rules, for example. To overcome these drawbacks, a Bottom-Up parser embedded in Prolog (BUP) has been developed. In BUP, CFG rules are translated into Prolog clauses which work as a bottom-up left corner parser with top-down expectation. BUP is augmented by introducing a “link” relation to reduce the size of a search space. Furthermore, BUP can be revised to maintain partial parsing results to avoid computational duplication. A BUP translator and a BUP tracer which support the development of grammar rules are described. 相似文献
996.
Dong Tu Chao-Nan Xu Sunao Kamimura Yoichi Horibe Hirotaka Oshiro Lu Zhang Yoshiharu Ishii Koji Hyodo Gerard Marriott Naohiro Ueno Xu-Guang Zheng 《Advanced materials (Deerfield Beach, Fla.)》2020,32(25):1908083
Ultrasensitive and sustainable near-infrared (NIR)-emitting piezoluminescence is observed from noncentrosymmetric and ferroelectric-phase Sr3Sn2O7 doped with rare earth Nd3+ ions. Sr3Sn2O7:Nd3+ (SSN) with polar A21am structure is demonstrated to emit piezoluminescence of wavelength of 800–1500 nm at microstrain levels, which is enhanced by the ferroelectrically polarized charges in the multipiezo material. These discoveries provide new research opportunities to study luminescence properties of multipiezo and piezo-photonic materials, and to explore their potential as novel ultrasensitive probes for deep-imaging of stress distributions in diverse materials and structures including artificial bone and other implanted structures (in vivo, in situ, etc). 相似文献
997.
Yasuhiro Iye Kimitoshi KŌno Koji Kajita Wataru Sasaki 《Journal of Low Temperature Physics》1980,38(3-4):293-310
Electron escape from the two-dimensional surface state is studied for liquid 4He and 3He surfaces. Experimental conditions are established under which proper signals are obtained to give the intrinsic escape rates. The escape rates in the temperature range 1.1 > T > 0.9 K for the 4He surface and 0.6 > T > 0.44 K for the 3He surface show the theoretically expected thermalactivation-type temperature dependence. In the present experimental configuration, the measured escape rate at higher electron densities explicitly demonstrates the electron correlation effect. A simple model is presented to account for the correlation effect on the binding energy of the surface electrons. 相似文献
998.
Inkjet-printed microfluidic multianalyte chemical sensing paper 总被引:2,自引:0,他引:2
This paper presents an inkjet printing method for the fabrication of entire microfluidic multianalyte chemical sensing devices made from paper suitable for quantitative analysis, requiring only a single printing apparatus. An inkjet printing device is used for the fabrication of three-dimensional hydrophilic microfluidic patterns (550-mum-wide flow channels) and sensing areas (1.5 mm x 1.5 mm squares) on filter paper, by inkjet etching, and thereby locally dissolving a hydrophobic poly(styrene) layer obtained by soaking of the filter paper in a 1 wt % solution of poly(styrene) in toluene. In a second step, the same inkjet printing device is used to print "chemical sensing inks", comprising the necessary reagents for colorimetric analytical assays, into well-defined areas of the patterned microfluidic paper devices. The arrangement of the patterns, printed inks, and sensing areas was optimized to obtain homogeneous color responses. The results are "all-inkjet-printed" chemical sensing devices for the simultaneous determination of pH, total protein, and glucose in clinically relevant concentration ranges for urine analysis (0.46-46 muM for human serum albumin, 2.8-28.0 mM for glucose, and pH 5-9). Quantitative data are obtained by digital color analysis in the L*a*b* color space by means of a color scanner and a simple computer program. 相似文献
999.
Masahiro Kihara Koji Miyazaki Hiroshi Tsukamoto 《International Journal of Thermophysics》2008,29(6):2136-2148
The spectral reflectance of microperiodic structures of silica microspheres was investigated. The electromagnetic dispersion
relation in a close-packed structure of silica spheres is computed. The three-dimensional close-packed structures, self-assembled
with silica microspheres (2 μm and 3 μm), were rapidly fabricated over a large area. Specular reflectance was measured by
using Fourier transform-infrared spectroscopy (FT-IR). The experimental results were evaluated by a modification of Bragg’s
law, taking into account Snell’s law of refraction, and calculations of multiple reflections and the scalar wave approximation
method. In addition, to expand the reflection wavelength range, a double-layered sample was fabricated, and its spectral reflectance
was determined. 相似文献
1000.
Performance of band shaped prefabricated vertical drain (PVD) installed into soft Hai Phong clay with a 110 cm triangle arrangement is reported together with the engineering properties of the clay investigated by field and laboratory tests. Stationary piston sampling was carried out to obtain high quality undisturbed soil samples for laboratory tests and reliable engineering characteristics of the clay. It was assumed for the design of PVD spacing and preloading that the ratio of apparent value of horizontal coefficient of consolidation ch(ap) to vertical coefficient of consolidation cv is equal to 1.0. The settlement monitored in the field, which clearly showed that the actual settlement was faster than expected, resulted in the ch(ap) value 1.5 times as much as cv determined by the laboratory test. 相似文献