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11.
New cellulosic titanium dioxide nanocomposite as a protective coating for preserving paper-art-works
We investigate the TiO2 role in the inherent protection of paper works of art to protect them against damaging effect of ultraviolet radiation, pollutant gasses, mold and bacteria. In this study a cellulosic nanocomposite of TiO2 were used as protective coating on the surface of paper fibers. This layered nanocomposite can act as a consolidate materials too. Furthermore, to determine how well paper works screen objects from the damaging effects, two accelerated aging mechanisms due to light and heat are discussed. Results show good stability of papers with nanocomposite coating. Also, a good light stability was shown in the colored paper that treated with this nanocomposite. Furthermore, to demonstrate the degree of antifungal properties of coated papers, papers were treated with two common molds and the good preventive effect of coated paper against molds is described. 相似文献
12.
In this paper, we study an adaptive random search method based on continuous action-set learning automaton for solving stochastic optimization problems in which only the noise-corrupted value of function at any chosen point in the parameter space is available. We first introduce a new continuous action-set learning automaton (CALA) and study its convergence properties. Then we give an algorithm for optimizing an unknown function. 相似文献
13.
Shaykh Muhammad al‐casnazāni al‐Husseini Jamāl N. Hussein Shetha al‐Dargazelli Hamid M. An‐Ni'aymi Louay J. Fatoohi 《Al-Masaq: Islam & the Medieval Mediterranean》1994,7(1):227-266
This pilot study presents a lunar and Gregorian chronology of the Sira, that is the biography of the prophet Muhammad. The paper discusses the problems surrounding the chronology of very early Islamic history, namely, the pre‐Hijra era. This history is not covered by the Hijra calendar, and therefore, historians dated its events using other primitive dating systems, resulting in considerable difficulties and inaccuracies when comparing Gregorian dates of this early Islamic history. In order to overcome this problem and establish an accurate chronology of the early Islamic history, the introduction of a new lunar calendar (the Muhammadi calendar) which starts with the birth month and year of the prophet Muhammad, and covers all Islamic history including the pre‐Hijra era, is suggested. The Muhammadi calendar was used to study the earliest three versions of the Sira. All dated events of the Sira were compiled from these sources and presented, for the first time, according to their historical order. The Muhammadi dates of these events were then calculated. For the first time, a computer program was designed to convert the Muliammadi dates to their Christian equivalent. The program was then used to compute the Gregorian dates of the events of the Sira. 相似文献
14.
AWAD Samir Hamid 《重庆大学学报(英文版)》2005,4(1)
1 Introduction Weight saving materials such as aluminum and its alloys are becoming increasingly important and have been attracting increasing attention over the past decade, specially in the automotive, aerospace and chemical industries, and electrical devices because of their high strength-to-weight ratio, high electrical and thermal conductivities, processability and recyclability and good resistance to degradation in some corrosive environments [1,2]. In the automotive industry, there is d… 相似文献
15.
M. Obaidul Hamid 《Discourse: Studies in the Cultural Politics of Education》2016,37(3):472-487
Globalized English proficiency tests such as the International English Language Testing System (IELTS) are increasingly playing the role of gatekeepers in a globalizing world. Although the use of the IELTS as a ‘policy tool’ for making decisions in the areas of study, work and migration impacts on test-takers' lives and life chances, not much is known about its own policy and policy logic. With the growing call for listening to test-takers' voices, specific policy aspects of the test have recently been scrutinized. This article seeks to contribute to this area by drawing on test-takers' perspectives on the IELTS retake policy and developing an understanding of how policies of global English tests are perceived, interpreted and given new meanings by its key stakeholders. Although the truth-value of the emic views of test-takers may be debated, their experiences and perceptions problematize the reliability claims of the testing agency by locating commercial motives at the center of their policy and thereby raising theoretical, professional and ethical questions. 相似文献
16.
David NICHOLAS Anthony WATKINSON Hamid R. JAMALI Eti HERMAN Carol TENOPIR Rachel VOLENTINE Suzie ALLARD Kenneth LEVINE 《Learned Publishing》2015,28(1):15-21
The article presents one of the main findings of an international study of 4,000 academic researchers that examined how trustworthiness is determined in the digital environment when it comes to scholarly reading, citing, and publishing. The study shows that peer review is still the most trustworthy characteristic of all. There is, though, a common perception that open access journals are not peer reviewed or do not have proper peer‐review systems. Researchers appear to have moved inexorably from a print‐based system to a digital system, but it has not significantly changed the way they decide what to trust. They do not trust social media. Only a minority – although significantly mostly young and early career researchers – thought that social media are anything other than more appropriate to personal interactions and peripheral to their professional/academic lives. There are other significant differences, according to the age of the researcher. Thus, in regard to choosing an outlet for publication of their work, young researchers are much less concerned with the fact that it is peer reviewed. 相似文献
17.
Zuolong Wei Kjell G. Robbersmyr Hamid R. Karimi 《Journal of The Franklin Institute》2017,354(12):4896-4912
As a complex process, vehicle crash is challenging to be described and estimated mathematically. Although different mathematical models are developed, it is still difficult to balance the complexity of models and the performance of estimation. The aim of this work is to propose a novel scheme to model and estimate the processes of vehicle-barrier frontal crashes. In this work, a piecewise model structure is predefined to represent the accelerations of vehicle in frontal crashes. Each segment in the model is corresponding to the energy absorbing component in the crashworthiness structure. With the help of Ensemble Empirical Mode Decomposition (EEMD), a robust scheme is proposed for parameter identification. By adjusting the model structure and parameters according to the initial velocity, crash processes in different conditions are estimated effectively. The estimation results exhibit good agreement with finite element (FE) simulations in three different cases. It is shown that, the proposed model keeps low complexity. Furthermore, the structure information of vehicle is involved in improving the accuracy and ability of crash estimation. 相似文献
18.
Shu-Ching Chen Min Chen Na Zhao Shahid Hamid Kasturi Chatterjee Michael Armella 《Government Information Quarterly》2009
Homeowner insurance rate making is an important public policy issue in the State of Florida. The State of Florida has over 2 trillion dollars of residential properties exposed to hurricane risk. The State has declared that it shall adopt public policy to encourage the use of sophisticated actuarial methods to assure that consumers are charged lawful insurance rates (Section 627.0628(1)(a)). To that effect, the State's insurance regulatory agency, the Florida Office of Insurance Regulation (OIR), sponsored the development of a Florida Public Hurricane Loss Model (FPHLM) to assess the risk and project insured residential losses. The FPHLM is an open and public model that has been developed primarily by university experts without influence from either the insurance industry or the state regulators. It is open to public scrutiny and provides an understandable baseline to check the assumptions as well as the outputs of the proprietary models. The FPHLM thus makes the rate evaluation process more objective and less political. It enables the state to justify rejecting or accepting rate increases based on an independent and transparent model, rather than a process that can be influenced politically. As a multi-disciplinary large scale research project with an iterative and incremental development cycle, the FPHLM system development and integration faced numerous challenges varying from technical factors to project management aspects. This paper will discuss the research experiences accumulated during the development of the FPHLM and the impact it has had on the homeowner insurance rate filing process in the State of Florida. 相似文献
19.
Shixiang Sun Xinjiang Wei Huifeng Zhang Hamid Reza Karimi Jian Han 《Journal of The Franklin Institute》2018,355(12):4897-4915
In this paper, a composite fault tolerant control (CFTC) with disturbance observer scheme is considered for a class of stochastic systems with faults and multiple disturbances. The disturbances are divided into two parts. One represents the stochastic disturbance with partial known information which is formulated by an exogenous system. The other is independent Wiener process. A stochastic disturbance observer is designed to estimate exogenous disturbance. To make the first type of disturbance can be rejected and the fault can be diagnosed, a composite fault diagnosis observer with disturbance observer is constructed. Furthermore, a composite fault-tolerant controller is proposed to compensate disturbances and faults. Finally, simulation examples are given to demonstrate the feasibility and effectiveness of the proposed scheme. 相似文献
20.
Yueyang Li Hamid Reza Karimi Choon Ki Ahn Yuan Xu Dong Zhao 《Journal of The Franklin Institute》2018,355(7):3330-3353
This work deals with the problem of optimal residual generation for fault detection (FD) in linear discrete time-varying (LDTV) systems subject to uncertain observations. By introducing a generalized fault detection filter (FDF) with four parameter matrices as the residual generator, a novel FDF design scheme is formulated as two bi-objective optimization problems such that the sensitivity of residual to fault is enhanced and the robustness of residual to unknown input is simultaneously strengthened. A generalized operator based optimization approach is proposed to deduce solutions to the corresponding optimization problems in operator forms, where the related H∞/H∞ or FD performance index is maximized. With the aid of the addressed methods, the connections among the derived solutions are explicitly announced. The parameter matrices of the FDF are analytically derived via solving simple matrix equations recursively. It is revealed that our proposed results establish an operator-based framework of optimal residual generation for some kinds of linear discrete-time systems. Illustrative examples are given to show the applicability and effectiveness of the proposed methods. 相似文献