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81.
Eugene Pozhidaev Vladimir Chigrinov Gurumurthy Hegde Peizhi Xu 《Journal of the Society for Information Display》2009,17(1):53-59
Abstract— Multistable electro‐optical modes exist under certain conditions in ferroelectric liquid‐crystal (FLC) cells, which means that any light‐transmission level can be memorized after the driving voltage is switched off. The multistability is responsible for three new electro‐optical modes with different shapes of the gray‐scale curve that can be either S‐shaped (double or single dependent upon the applied‐voltage pulse sequence and boundary conditions) or V‐shaped dependent upon boundary conditions and FLC cell parameters. The origin of these modes will be described. 相似文献
82.
Zambia Consolidated Copper Mines Ltd. (ZCCM) is planning a substantial increase in ore production in several of their underground mines on the Zambian Copperbelt over the next 10 years. The future production strategy is based on development of productive and economic mining methods through the application of mechanization and backfilling. Mechanization is designed to provide the production capability and the backfilling is designed to reduce water inflow into the mines. A similar trend can be seen in world-wide changes in mining methods from open stoping and sub-level caving to cut-and-fill stoping. Backfill is being employed worldwide, including in Australia, Canada, Sweden, Latin America, Zambia, and the U.S.A. Plans for backfill mining methods are underway for future operations in Chile, Canada, Zambia, and Mexico. The principal reasons for these changes in mining methods are twofold: ? Increased ore recovery, and ? Decreased environmental impact. The main difference in the environmental impacts between mining with sub-level caving or open stoping and mining with backfilling methods is the reduction in subsidence or the potential for subsidence. Backfilling reduces ground movements in the rock overlying and adjacent to mine openings as well as subsidence at the surface. Reduced ground movement decreases the number and size of fracture-controlled hydraulic flow paths into a mine and, thereby, the impact of mining on surface and ground water resources. This paper deals with: 1) The impacts caused by open stoping and sub-level caving in comparison to backfilling methods; 2) The approximate impact of backfill on dewatering strategies, and; 3) The environmental benefits of backfill mining. The differences in mine drainage strategies are supported by case histories from various mines. 相似文献
83.
Composite Materials Based on Shape‐Memory Ti2NiCu Alloy for Frontier Micro‐ and Nanomechanical Applications
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84.
Chung Yen Ang Si Yu Tan Cathleen Teh Jia Min Lee Mun Fei Eddy Wong Qiuyu Qu Li Qing Poh Menghuan Li Yuanyuan Zhang Vladimir Korzh Yanli Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(7)
Responsive nanomaterials have emerged as promising candidates as drug delivery vehicles in order to address biomedical diseases such as cancer. In this work, polymer‐based responsive nanoparticles prepared by a supramolecular approach are loaded with doxorubicin (DOX) for the cancer therapy. The nanoparticles contain disulfide bonds within the polymer network, allowing the release of the DOX payload in a reducing environment within the endoplasm of cancer cells. In addition, the loaded drug can also be released under acidic environment. In vitro anticancer studies using redox and pH dual responsive nanoparticles show excellent performance in inducing cell death and apoptosis. Zebrafish larvae treated with DOX‐loaded nanoparticles exhibit an improved viability as compared with the cases treated with free DOX by the end of a 3 d treatment. Confocal imaging is utilized to provide the daily assessment of tumor size on zebrafish larva models treated with DOX‐loaded nanoparticles, presenting sustainable reduction of tumor. This work demonstrates the development of functional nanoparticles with dual responsive properties for both in vitro and in vivo drug delivery in the cancer therapy. 相似文献
85.
86.
87.
Vladimir Z. Kresin Stuart A. Wolf Yu. N. Ovchinnikov 《Journal of Superconductivity》1996,9(3):329-333
The value of the critical temperature of the cuprates correlates with the doping level and is affected by the interplay of two competing factors: (1) the increase in carrier concentration, and (2) the pair-breaking effect of magnetic impurities. An analysis of the temperature dependence of the critical field leads to the conclusion that magnetic impurities are present even in a sample with the maximum observed value ofT
c.A new parameter, intrinsicT
c (T
cintr), which is its value in the absence of magnetic impurities, is introduced. The maximum value ofT
cintr, which corresponds to the maximum doping level, appears to be similar for different cuprates and to be equal to 160–170 K. This is the upper limit ofT
c in the cuprates. 相似文献
88.
Consider an m-machine production line for processing identical parts served by a mobile robot. The problem is to find the minimum cycle
time for 2-cyclic schedules, that is, schedules in which exactly two parts enter and two parts leave the production line during
each cycle. This work treats a special case of the 2-cyclic robot scheduling problem when the robot route is given and operation
durations are chosen from prescribed intervals. A strongly polynomial algorithm of time complexity O(m
8log m) is proposed. 相似文献
89.
We address the sequence classification problem using a probabilistic model based on hidden Markov models (HMMs). In contrast
to commonly-used likelihood-based learning methods such as the joint/conditional maximum likelihood estimator, we introduce
a discriminative learning algorithm that focuses on class margin maximization. Our approach has two main advantages: (i) As
an extension of support vector machines (SVMs) to sequential, non-Euclidean data, the approach inherits benefits of margin-based
classifiers, such as the provable generalization error bounds. (ii) Unlike many algorithms based on non-parametric estimation
of similarity measures that enforce weak constraints on the data domain, our approach utilizes the HMM’s latent Markov structure
to regularize the model in the high-dimensional sequence space. We demonstrate significant improvements in classification
performance of the proposed method in an extensive set of evaluations on time-series sequence data that frequently appear
in data mining and computer vision domains. 相似文献
90.
In this paper we consider a special class of integral delay systems arising in several stability problems of time‐delay systems. For these integral systems we derive stability and robust stability conditions in terms of Lyapunov–Krasovskii functionals. More explicitly, after providing the stability conditions we compute quadratic functionals and apply them to derive exponential estimates for solutions, and robust stability conditions for perturbed integral delay systems. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献