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81.
The present study was carried out to determine the effect of ozonated water (2 mg L?1) at different temperatures (4 °C and 15 °C) on the microbiological, color and sensory properties of lettuce. Cold ozone treatment (4 °C) significantly reduced the natural background microflora of lettuce. Salmonella Typhimurium and Escherichia coli inoculated on lettuce samples were insignificantly influenced by the temperature of water. During storage period at +4 °C for 14 days, the highest quality was observed from the samples treated with cold ozonated water. Ozone treatments did not affect the color properties and sensory quality of lettuce samples. 相似文献
82.
In this study, we propose an automatic contrast enhancement method based on transfer function modification (TFM) by histogram equalization. Previous histogram‐based global contrast enhancement techniques employ histogram modification, whereas we propose a direct TFM technique that considers the mean brightness of an image during contrast enhancement. The mean point shifting method using a transfer function is proposed to preserve the mean brightness of an image. In addition, the linearization of transfer function technique, which has a histogram flattening effect, is designed to reduce visual artifacts. An attenuation factor is automatically determined using the maximum value of the probability density function in an image to control its rate of contrast. A new quantitative measurement method called sparsity of a histogram is proposed to obtain a better objective comparison relative to previous global contrast enhancement methods. According to our experimental results, we demonstrated the performance of our proposed method based on generalized measures and the newly proposed measurement. 相似文献
83.
This study aims to explore the ways of involving children with autism in participatory product design processes. Due to the impaired skills of children with autism, a key aspect of the process is to gain an understanding of the nature of the disorder and how these children interact with their social and material surroundings as well as their daily life problems. Considering this, a case study was conducted with children with autism, their parents and teachers, and also industrial design students in a public special education centre in ?zmir, Turkey. The design task was to reconsider the conventional trampoline design with respect to the needs of the sample group and the special education centre as well as the benefits it provides. The task was based on the patterns of behaviours, actions and movement. Observations, interviews and questionnaires were carried out, as well as collaborative meetings and discussion meetings. Through the case study, the findings provided insights into conducting a participatory process with children with autism, the roles of the participants, and the interaction and communication among them. Furthermore, participants’ attitude towards participatory design, the potential benefits of the design process, and innovations to benefit children with autism were explained. 相似文献
84.
Transition metal cations extraction by ester and ketone derivatives of chromogenic azocalix[4]arenes 总被引:1,自引:0,他引:1
The molecule of azocalix[n]arene is a macrocyclic used effectively in the complexation of the heavy metal pollutants (like silver and mercury). In this work, our main aim is to prepare new chromogenic azocalix[n]arene molecules to elaborate an extractant with high extractant selectivity for metal ions able to detect this type of pollutant. The solvent extraction properties of four acetyls, four methyl ketones and four benzoyls derivatives from azocalix[4]arenes which were prepared by linking 4-ethyl, 4-n-butyl, 4-acetamid anilin and 2-aminothiazol to calix[4]arene through a diazo-coupling reaction, the alkaline earth (Sr2+) and the transition (Ag+, Hg2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Cr3+) metal cations have been determined by extraction studies with metal picrates. Both ketones are better extractants than esters, and show a strong preference for Ag+, while Cu2+ and Cr3+ are the most extracted cation with the esters. Both acetyl and benzoyl esters are good carriers for Ag+ and Hg2+. 相似文献
85.
Single-molecule biophysics: at the interface of biology, physics and chemistry 总被引:2,自引:0,他引:2
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Ashok A Deniz Samrat Mukhopadhyay Edward A Lemke 《Journal of the Royal Society Interface》2008,5(18):15-45
Single-molecule methods have matured into powerful and popular tools to probe the complex behaviour of biological molecules, due to their unique abilities to probe molecular structure, dynamics and function, unhindered by the averaging inherent in ensemble experiments. This review presents an overview of the burgeoning field of single-molecule biophysics, discussing key highlights and selected examples from its genesis to our projections for its future. Following brief introductions to a few popular single-molecule fluorescence and manipulation methods, we discuss novel insights gained from single-molecule studies in key biological areas ranging from biological folding to experiments performed in vivo. 相似文献
86.
We propose the information regularization principle for fusing information from sets of identical sensors observing a target
phenomenon. The principle basically proposes an importance-weighting scheme for each sensor measurement based on the mutual
information based pairwise statistical similarity matrix between sensors. The principle is applied to maximum likelihood estimation
and particle filter based state estimation. A demonstration of the proposed regularization scheme in centralized data fusion
of dense motion detector networks for target tracking is provided. Simulations confirm that the introduction of information
regularization significantly improves localization accuracy of both maximum likelihood and particle filter approaches compared
to their baseline implementations. Outlier detection and sensor failure detection capabilities, as well as possible extensions
of the principle to decentralized sensor fusion with communication constraints are briefly discussed.
相似文献
Umut OzertemEmail: |
87.
The algorithm given by Rouanne and Costello (1989) for the computation of the distance spectrum is improved for trellis-coded modulation schemes having uncoded bits, i.e., for trellis diagrams having parallel paths. It is shown that, when through a trellis corresponding to such kind of codes, all parallel transitions (labeled by signal selectors) between states are considered as a single branch labeled by a subset, then defining subset selector distance polynomials makes the computational complexity of the distance spectrum dependent on the number of states as compared to the complexity of Rouanne and Costello algorithm which depends on the number of paths to be extended 相似文献
88.
Yucel Birol 《Journal of Materials Science》2010,45(16):4501-4506
CuCrZr alloy offers good mechanical and thermal properties and was investigated in the present work for its potential as tooling
material in thixoforming of steels. Samples of CuCrZr alloy were cycled thermally between 450 and 750 °C, every 60 s. The
thermal conductivity of the CuCrZr alloy, nearly an order of magnitude higher with respect to that of the conventional hot
work tool steel, proved to be very beneficial in terms of thermal stresses generated at the surface upon thermal cycling.
The maximum compressive and tensile stresses produced at the front face of the CuCrZr alloy were estimated to be approximately
30 and 10 MPa, respectively, much smaller than those endured by the conventional hot work tool steel. The very favourable
thermal stress state in the CuCrZr alloy die was largely negated, however, due to its inferior resistance to high temperature
oxidation. 相似文献
89.
Fatih Deniz 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2821-2826
The objective of this research paper is to assess the biosorption potential of almond shell residues for methyl orange dye. The pseudo-second-order kinetic model described the dye biosorption process with a good fitting. The relationship between the pseudo-second-order model constants and the biosorption performance was also evaluated. The equilibrium data fit well with the Langmuir isotherm model presenting that the biosorption was the monolayer coverage of dye on the biosorbent and the homogeneity of active sites for dye binding on the biosorbent surface. Based on the Langmuir model, a single-stage batch biosorber was also designed to predict the biosorbent mass for certain percentage dye removal. Besides, the standard Gibbs free energy change was also calculated to define the nature of biosorption process. These results revealed that the utilization of almond shell residues as dye biosorbent could be an interesting option from both environmental and economic point of view. 相似文献
90.
Deniz Türsel Eliiyi 《国际生产研究杂志》2013,51(21):6211-6233
In this study we consider the operational fixed job scheduling problem under working time limitations. The problem has several practical implications in both production and service operations; however the relevant research is scarce. We analyse pre-emptive and non pre-emptive versions of the problem and its special cases. We provide polynomial-time algorithms for some special cases. We show that the non pre-emptive jobs problem is strongly NP-hard, and propose a branch-and-bound algorithm that employs efficient bounding procedures and dominance properties. We conduct a numerical experiment to observe the effects of parameters on the quality of the solution. The results of our computational tests for the branch-and-bound algorithm reveal that our algorithm can solve the instances with up to 100 jobs in reasonable times. To the best of our knowledge our branch-and-bound algorithm is the first optimisation attempt to solve the problem. 相似文献