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Cloud service providers offer virtual resources to users, who then pay for as much as they use. High‐speed networks help to overcome the limitation of geographical distances between clients and cloud servers, which encourage users to adopt cloud storage services for data backup and sharing. However, users use only a few cloud storage services because of the complexity of managing multiple accounts and distributing data to store. In this paper, we propose the client‐defined management architecture (CLIMA) that redefines a storage service by coordinating multiple cloud storage services from clients. We address practical issues of coordinating multiple cloud service providers using a client‐based approach. We implement a prototype as a realization of CLIMA, which achieves both reliability and privacy protection using erasure code and higher performance by optimally scheduling data transmission. We use our prototype to evaluate the benefits of CLIMA on commercial cloud storage service providers. Finally, CLIMA empowers clients to increase the manageability and flexibility of cloud storage services. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
74.
A novel interconnection technology based on a 52InSn solder was developed for flexible display applications. The display industry is currently trying to develop a flexible display, and one of the crucial technologies for the implementation of a flexible display is to reduce the bonding process temperature to less than 150°C. InSn solder interconnection technology is proposed herein to reduce the electrical contact resistance and concurrently achieve a process temperature of less than 150°C. A solder bump maker (SBM) and fluxing underfill were developed for these purposes. SBM is a novel bumping material, and it is a mixture of a resin system and InSn solder powder. A maskless screen printing process was also developed using an SBM to reduce the cost of the bumping process. Fluxing underfill plays the role of a flux and an underfill concurrently to simplify the bonding process compared to a conventional flip‐chip bonding using a capillary underfill material. Using an SBM and fluxing underfill, a 20 μm pitch InSn solder SoP array on a glass substrate was successfully formed using a maskless screen printing process, and two glass substrates were bonded at 130°C.  相似文献   
75.
Summary Three kinds of aromatic polyamides were synthesized by Higashi reaction: aromatic polyamides with even, odd number of methylenes and a meta phenylene as a joint in the main chain. Each polymer consisted of 7 p-phenylene-amide elements as a rigid segment. The polymer with even number of methylenes showed a lyotropic liquid crystalline behavior and a broader biphasic region than the fully para aromatic polyamide such as poly(p-phenylene terephthalamide). Most polymers with odd number of methylenes did not form a liquid crystalline phase and showed a crystallo-solvate. Exceptionally, the polymer with glutaryl unit was observed to have the swollen gel of colored pattern by the polarized microscope. The zigzag polymer, characterized by the highly kinetic rigidity, revealed an anisotropic gel phase in a solution.  相似文献   
76.
An absorption efficiency of packed column removing nitrogen oxides with water and NaOH solution under atmospheric pressure was studied. The efficiency and the acidity produced by absorption of NO, were measured in a packed column. The model developed that was based on the mass-transfer information for packed column and absorption mechanism accompanying the chemical reaction was compared with experimental results. Predictions using the model presented by the previous paper (part 1) was shown well to agree with from the experimental results (part II). The efficiency of NOx, absorption is largely dependent on the height of packing material and the partial pressure of NOx in the feed gas. The efficiency of NOx absorption decreases with the increase of the acidity produced by recycling of water as a scrubber liquid. For the recycle mode with an aqueous NaOH solution as a scrubber liquid, NOx absorption efficiency is shown to be constant until all of the COH- in the scrubber liquid are converted into CH+.  相似文献   
77.
The effect of prereduction on CO oxidation activity of unsupported copper-chromite oxide catalysts was examined. Results were found to be in good agreement with two mechanisms for a surface copper enrichment due to CO prereduction which produced an activity increase in the copper-chromite catalyst.  相似文献   
78.
The effects of ZrO2 and Y2O3 on the densification of hotpressed Si3N4-Zr(Y)O2 composites have been studied. High density could not be obtained by the addition of pure or 3-mol%-Y2O3-doped ZrO2 in this composite; however, nearly full density (>97%) could be obtained in Si3N4 using 6- and 8-mol%-Y2O3-doped ZrO2. It is concluded that Y2O3 diffusing out from the added Zr(Y)O2 promoted the densification and that ZrO2 also had some role in the formation of an oxynitride glass.  相似文献   
79.
We propose two improved scalar multiplication methods on elliptic curves over Fqn where q = 2m using Frobenius expansion. The scalar multiplication of elliptic curves defined over subfield Fq can be sped up by Frobenius expansion. Previous methods are restricted to the case of a small m. However, when m is small, it is hard to find curves having good cryptographic properties. Our methods are suitable for curves defined over medium‐sized fields, that is, 10 ≤ m ≤ 20. These methods are variants of the conventional multiple‐base binary (MBB) method combined with the window method. One of our methods is for a polynomial basis representation with software implementation, and the other is for a normal basis representation with hardware implementation. Our software experiment shows that it is about 10% faster than the MBB method, which also uses Frobenius expansion, and about 20% faster than the Montgomery method, which is the fastest general method in polynomial basis implementation.  相似文献   
80.
We propose an efficient scheme for camera motion characterization in MPEG‐compressed video. The proposed scheme detects six types of basic camera motions through threshold‐based qualitative interpretation, in which fixed thresholds are applied to motion model parameters estimated from MPEG motion vectors (MVs). The efficiency and robustness of the scheme are validated by the experiment with real compressed video sequences.  相似文献   
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