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排序方式: 共有2722条查询结果,搜索用时 15 毫秒
51.
This paper aims to assess quantitatively the actual visual environment of uncontrolled urban downtown intersections in Japan in relation to frequently occurring crossing collisions and to discuss the safety countermeasures for them. In Field Study 1 dealing with direct visibility, our ultra-wide-angle photograph analysis revealed that most of the right/left-ward visible range at 11 intersections were insufficient to check safety, and the quality of direct visibility was closely associated with causing crossing collisions. The countermeasures to reduce a blind area were determined to be a top priority. In Field Study 2 dealing with indirect visibility, more than half of the 25 traffic convex mirrors had marked shortcomings for preventive safety, and ergonomics guidelines ensuring indirect visibility were proposed for installing traffic convex mirrors. Low-cost/low-technology-oriented countermeasures are highly recommended to obtain clear/sufficient images of crucial information satisfying drivers' requirements on traffic convex mirrors in accordance with those ergonomics guidelines was highly recommended. Crossing collisions could be prevented by improvement of poor direct and indirect visibility. 相似文献
52.
C. Bäuerle N. Mori G. Kurata Hiroshi Fukuyama 《Journal of Low Temperature Physics》1998,113(5-6):927-932
Scanning tunneling microscopy (STM) studies of two-dimensional (2D) cryocrystals
4
He, Kr, Xe) physisorbed on graphite surfaces are presented. Individual helium atoms, usually thought to be invisible with STM, were recently observed on graphite surfaces at a density corresponding to the
commensurate solid. Here we show that a local elastic deformation seems to be the principal mechanism responsible to render the atoms visible. Recent tight-binding calculations of the local density of states (LDOS) of graphite which predict the appearance of an energy gap support this picture. I-z curve measurements for the case of
4
He show a sharp drop (increase) of the tunneling current I at a certain tip-surface distance z during retraction (approach) of the tip. This drop (increase) may be associated with the tunneling of a single He adatom, opening new possibilities to study the quantum tunneling of atoms via STM. 相似文献
53.
We analyze the linearity and modulation depth of ac magnetic-field sensors or current sensors, using a ferrimagnetic or ferromagnetic film as the Faraday rotator and employing the detection of only the zeroth-order optical diffraction component from the rotator. It is theoretically shown that for this class of sensor the condition of a constant modulation depth and that of a constant ratio error give an identical series of curves for the relationship between Faraday rotation angle Θ and polarizer/analyzer relative angle Φ. We give some numerical examples to demonstrate the usefulness of the result with reference to a rare-earth iron garnet film as the rotator. 相似文献
54.
Juichiro Arai Katsuhiro Kojima Nobuhide Mori 《Journal of Low Temperature Physics》1996,105(3-4):455-460
Fe3+-ESR measurements are carried out for the samples of (La1–xSrx)2Cu1–yFeyO4–z. Peak-peak width Hpp of the signals decreases with falling temperature until minimum value and rises sharply with further decreasing temperature, which is approximated by Hpp = C0 +C1/T + BT. The Hpp behavior at high temperature and at low temperature can be analyzed by Korringa mechanism and slowing down of Fe3+ spin fluctuation, respectively. From the analysis of coefficient B's of Korringa terms, C0 and g-shift, it is revealed that the magnetic interaction of Fe3+ with hole carriers and Ce2+ spins depends strongly on hole density. 相似文献
55.
56.
Caio César Mori Carélo Ives Renê Venturini Pola Ricardo Rodrigues Ciferri Agma Juci Machado Traina Caetano Traina Jr Cristina Dutra de Aguiar Ciferri 《Information Systems》2011
Searching in a dataset for elements that are similar to a given query element is a core problem in applications that manage complex data, and has been aided by metric access methods (MAMs). A growing number of applications require indices that must be built faster and repeatedly, also providing faster response for similarity queries. The increase in the main memory capacity and its lowering costs also motivate using memory-based MAMs. In this paper, we propose the Onion-tree, a new and robust dynamic memory-based MAM that slices the metric space into disjoint subspaces to provide quick indexing of complex data. It introduces three major characteristics: (i) a partitioning method that controls the number of disjoint subspaces generated at each node; (ii) a replacement technique that can change the leaf node pivots in insertion operations; and (iii) range and k-NN extended query algorithms to support the new partitioning method, including a new visit order of the subspaces in k-NN queries. Performance tests with both real-world and synthetic datasets showed that the Onion-tree is very compact. Comparisons of the Onion-tree with the MM-tree and a memory-based version of the Slim-tree showed that the Onion-tree was always faster to build the index. The experiments also showed that the Onion-tree significantly improved range and k-NN query processing performance and was the most efficient MAM, followed by the MM-tree, which in turn outperformed the Slim-tree in almost all the tests. 相似文献
57.
Keiji Hayashi Tomoki Shiraishi Kazuho Toyoda Fumiya Tanaka Taiga Mori Takumi Hata 《Computer Physics Communications》2011,(9):2032-2035
Laws of dynamic nano-friction (i.e., continuous wearless friction) were searched for under steady spatial distributions of the local quasi-temperature, by molecular dynamics (MD) simulations. The temperature control of the non-conservative model was carried out by extending the isothermal MD method using the Nosé–Poincaré thermostat. The results suggested that the threshold phenomenon characterizes sliding-velocity dependence of the nano-frictional force between crystal lattices constituting a nano-electromechanical system (NEMS). This phenomenon was turned out to be a universal feature, whether heat transfer to the environment exists or not. 相似文献
58.
T. Iwashita K. Yosui M. Mori E. Kobayashi S. Abe 《Computing and Visualization in Science》2008,11(3):123-128
A multi-grid method is one of the most powerful linear solvers for finite element electromagnetic field analysis. However,
as the discretized model has recently been enlarged, a solution process for a linear system arising on the coarsest level
tends to be problematic in a complete multi-grid solution process. Whereas a linear system on the coarsest level is generally
solved by a direct solver, we solve it here by means of an iterative solver to reduce the memory requirements. Since a conventional
preconditioning technique is not effective for such a linear system, we introduce preconditioning techniques based on Arnold,
Falk, and Winther’s and on Hiptmair’s smoothers. Numerical tests show that the newly installed preconditioning technique greatly
improves the convergence rate. 相似文献
59.
Report on highly automated works in Japan — management of labour in line with technology development
In recent years drastic shifts in the paradigms of politics, economics and technologies have occurred throughout the world. The shifts in these three fields are all related. It is our responsibility to investigate these shifts from the aspects of society and mankind for the prosperity of future generations. For this, societies should share with each other their wisdom and knowledge in an effort to plan for the future.Presented at conference on Ecology of Science and Technology, Japan Science Foundation, Tokyo, 1992. 相似文献
60.
Research on machine recognition of handprinted characters 总被引:5,自引:0,他引:5
Mori S Yamamoto K Yasuda M 《IEEE transactions on pattern analysis and machine intelligence》1984,(4):386-405
Machine recognition of handprinted Chinese characters has recently become very active in Japan. Both from the practical and the academic point of view, very encouraging results are reported. The work is described systematically and analyzed in terms of so-called feature matching, which is likely to be the mainstream of the research and development of machine recognition of handprinted Chinese characters. A database, ETL8 (881 Kanji, 71 hirakana, and 160 variations for each category), is explained, on which many experiments were performed. Recognition rates reported using this database can be compared, and so somewhat qualitative evaluation of these methods is described. Based on the comparative study, the merits and demerits of both feature and structural matching are discussed and some future directions are mentioned. 相似文献