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排序方式: 共有1049条查询结果,搜索用时 359 毫秒
11.
Two problems were solved theoretically on the heat transfer to circular tube flow with internal heat source. The one problem is to maintain the mixed-mean temperature of fluid at the inlet temperature. The other is a conjugated problem with a uniformly specified temperature at the outside surface of the wall, accounting for the wall conduction. From the numerical example for the former, it is shown that the mixed-mean temperature can be controlled within 15% error under the estimated condition. From the numerical results for the latter, it is concluded that the influence of wall conduction is more serious than the case without heat generation. 相似文献
12.
ABSTRACT Preparation of poly(thiophene-alt-pyrrole bearing mesogen) was carried out with Migita–Kosugi–Stille coupling type polycondensation with an aid of Pd(0) complex catalyst. The resultant polymer shows lyotropic liquid crystallinity with good film-forming property. The smectic fan-shaped texture is maintained after completion of evaporation of solvent from the polymer solution. The cast film having liquid crystal (LC) order shows light emission function upon irradiation of excitation light at 460 nm. The polymer shows LC domain emission. Mechanical orientation allows to yield LC domain aligned film with band structure. Chiral mesogenic side chain induces π-conjugated main chain helicity from distance in molecular level. 相似文献
13.
Two‐way multi‐view 2‐D/3‐D display combining LC lens and HVxDP panel using novel pixel arrangement
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Jin Matsushima Yukie Ibata Kazunori Masumura Takuya Asai Tetsushi Sato Koji Shigemura 《Journal of the Society for Information Display》2016,24(4):252-261
We have developed a two‐way multi‐view 2‐D/3‐D display combining a liquid crystal lens and horizontally and vertically x times‐density pixels (HVxDP) arrangement. The two‐way multi‐view display features the same display resolution in 2‐D and 3‐D modes and a quite small color moiré for landscape and portrait, respectively, when using the HVxDP arrangement. In this paper, we realized suitable 3‐D properties for achieving a good balance between 3‐D moiré and 3‐D crosstalk for landscape and portrait by a two‐way liquid crystal lens with two kinds of focal lengths for the edge part and the center part of the lens. 相似文献
14.
Ryu Komatsu Ryo Nakazato Takeru Sasaki Akio Suzuki Naoyuki Senda Takuya Kawata Yasuhiro Jimbo Tomoya Aoyama Naoto Ohno Susumu Kawashima Hisao Ikeda Shingo Eguchi Yoshiharu Hirakata Shunpei Yamazaki Takashi Shiraishi Seiji Yasumoto Masataka Nakada Masataka Sato Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2015,23(2):41-49
In this study, a 5.9‐inch foldable active‐matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10?6 g/m2?day or less, which improves OLED reliability. With these techniques, we have developed a book‐type display, which is repeatedly foldable like a book, and a tri‐fold display including a display area, which is foldable in three. 相似文献
15.
Fengrong LI Takuya IIDA Yoshiharu ISHIKAWA 《Frontiers of Computer Science in China》2008,2(3):257-267
In recent years, peer-to-peer (P2P) technologies are used for flexible and scalable information exchange in the Internet,
but there exist problems to be solved for reliable information exchange. It is important to trace how data circulates between
peers and how data modifications are performed during the circulation before reaching the destination for enhancing the reliability
of exchanged information. However, such lineage tracing is not easy in current P2P networks, since data replications and modifications
are performed independently by autonomous peers—this creates a lack of reliability among the records exchanged. In this paper,
we propose a framework for traceable record exchange in a P2P network. By managing historical information in distributed peers,
we make the modification and exchange histories of records traceable. One of the features of our work is that the database
technologies are utilized for realizing the framework. Histories are maintained in a relational database in each peer, and
tracing queries are written in the datalog query language and executed in a P2P network by cooperating peers. This paper describes
the concept of the framework and overviews the approach to query processing. 相似文献
16.
Quad-trees, oct-trees, and k-trees: a generalized approach to recursive decomposition of euclidean space 总被引:1,自引:0,他引:1
Jackins CL Tanimoto SL 《IEEE transactions on pattern analysis and machine intelligence》1983,(5):533-539
K-trees are developed as a K-dimensional analog of quad-trees and oct-trees. K-trees can be used for modeling K-dimensional data. A fast algorithm is given for finding the boundary size of a K-dimensional object represented by a K-tree. For K considered as con-stant; the algorithm provides a method for computing the perimeter of a quad-tree encoded image or the surface area of an oct-tree encoded object in worst case time proportional to the number of nodes in the tree. This improves upon the expected-case linear-time method of Samet [10] for the perimeter problem. Our method has been implemented in Pascal, and a computational example is given. 相似文献
17.
Suppose that some particular link in the Internet is currently
congested.
A natural solution is to try to make packets bypass that link.
This can be done by increasing the cost of that link intentionally,
say from a
1 to a
2, since the Internet uses shortest-path
routing. Unfortunately, however, this often causes temporary loops
for packet traveling, called routing loops. In this paper
we show that routing loops can be avoided by increasing the cost
of the link not directly from a
1 to a
2 but through an
intermediate value, a
3, i.e., from a
1 to a
3 and then
to a
2.
We may need several
intermediate values.
We show that in this case
the greedy strategy,
namely, raising the cost as much as possible in each step,
is optimal. 相似文献
18.
Allen R. Cinque L. Tanimoto S. Shapiro L. Yasuda D. 《Parallel and Distributed Systems, IEEE Transactions on》1997,8(5):490-501
Search of discrete spaces is important in combinatorial optimization. Such problems arise in artificial intelligence, computer vision, operations research, and other areas. For realistic problems, the search spaces to be processed are usually huge, necessitating long computation times, pruning heuristics, or massively parallel processing. We present an algorithm that reduces the computation time for graph matching by employing both branch-and-bound pruning of the search tree and massively-parallel search of the as-yet-unpruned portions of the space. Most research on parallel search has assumed that a multiple-instruction-stream/multiple-data-stream (MIMD) parallel computer is available. Since massively parallel stream (SIMD) computers are much less expensive than MIMD systems with equal numbers of processors, the question arises as to whether SIMD systems can efficiently handle state-space search problems. We demonstrate that the answer is yes, and in particular, that graph matching has a natural and efficient implementation on SIMD machines 相似文献
20.
Hiroki Uehara Takuya Tamura Masaki Kakiage Takeshi Yamanobe 《Advanced functional materials》2012,22(10):2048-2057
Crystalline homopolymers, including polyethylene (PE), which has the simplest architecture, form a nanometer‐sized combination of crystalline and amorphous components, but their arrangement control, similar to self‐assembled phase‐separation of block‐copolymers, is usually difficult. However, molecular entanglements trapped between crystalline and amorphous components of homopolymers coincide with the segmental linking points on the interfaces of the microphase separation for block copolymers. Nanowrinkled PE membranes are prepared with a network of 30 nm‐thick homogeneous lamellae using a novel entanglement control technique composed of biaxial melt‐drawing and melt‐shrinking procedures, which are limited for highly entangled ultrahigh molecular weight materials. Such a network arrangement of nanowrinkling lamellae spreading on membrane surface and also across the membrane thickness improves the mechanical properties of both tensile strength and tearing strength. Subsequent cold‐drawing causes delamination of the lamellar interfaces, leading to the resultant nanoporous morphology composed of passing‐through channels that are several tens of nanometers in diameter, without any solvent processing. 相似文献