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991.
Syed M. Nasar‐Abbas Zill‐ e‐Huma Thi‐Huong Vu Muhammad Kamran Khan Henry Esbenshade Vijay Jayasena 《Comprehensive Reviews in Food Science and Food Safety》2016,15(1):63-72
Carob (Ceratonia siliqua L.) is well known for its valuable locust bean gum obtained from the carob seeds. Separation of seeds from the pod leaves behind the carob kibble which is a good source of dietary fiber, sugars, and a range of bioactive compounds such as polyphenols and pinitol. Bioactive compounds present in carob kibble have been found to be beneficial in the control of many health problems such as diabetes, heart diseases, and colon cancer due to their antidiabetic, antioxidant, and anti‐inflammatory activities. Carob kibble has substantial potential to be used as a food ingredient. This article focuses on the composition, health benefits, and food applications of carob kibble. 相似文献
992.
In nature, objects have partially weak texture and their shape reconstruction using focus based passive methods like shape from focus (SFF), is difficult. This article presents a new SFF algorithm which can compute precise depth of dense as well as weak textured objects. Segmentation is applied to discard wrong depth estimate and then later interpolating them from accurate depth values of their neighbors. The performance of the proposed method is tested, using different image sequences of synthetic and real objects, with varying textures. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc. 相似文献
993.
Nasir Abbas Muhammad Riaz Ronald J. M. M. Does 《Quality and Reliability Engineering International》2013,29(5):653-663
Control charts are the most extensively used technique to detect the presence of special cause variations in processes. They can be classified into memory and memoryless control charts. Cumulative sum and exponentially weighted moving average control charts are memory‐type control charts as their control structures are developed in such a way that the past information is not ignored as it is done in the case of memoryless control charts, like the Shewhart‐type control charts. The present study is based on the proposal of a new memory‐type control chart for process dispersion. This chart is named as CS‐EWMA chart as its plotting statistic is based on a cumulative sum of the exponentially weighted moving averages. Comparisons with other memory charts used to monitor the process dispersion are done by means of the average run length. An illustration of the proposed technique is done by applying the CS‐EWMA chart on a simulated dataset. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
994.
Asep Suhendi Muhammad Miftahul Munir Adi Bagus Suryamas Asep Bayu Dani Nandiyanto Takashi Ogi Kikuo Okuyama 《Advanced Powder Technology》2013,24(2):532-536
A new electrospray system has been successfully developed by employing a proportional–integral–derivative control action to maintain an electric current at a certain value. A polymer precursor solution containing polyethylene glycol was used to examine the performance of this system. The result showed that cone-jet geometry could be controlled easily by adjusting the electric current. The length of the cone-jet decreased as the electric current was increased, in a correlation that followed power law. We also found that the cone-jet observed during electrospraying was stable and robust with no disturbance during long periods of use (up to 4000 s). The present study is very useful for further development of high precision aerosol generators and particle synthesis. 相似文献
995.
We derive analytic expressions for the polarization characteristics of light emerging from a magneto-optical medium possessing arbitrary contributions from linear and circular birefringence as well as magnetic circular dichroism. The medium is placed inside a static magnetic field. The rotation of the plane of polarization and the ellipticity of the resultant light exhibit interesting characteristics that can be a useful guide in the design and analysis of new photonic devices. Furthermore, the Jones matrices are derived in all cases, including for elliptical dichroism, indicating the role of hyperbolic trigonometric functions in modeling the effects of dichroism. Finally, implications for experimental detection of the polarization state and the limits on the performance of optical isolators are discussed. 相似文献
996.
In this paper, the simulation of 60 GHz millimeter-wave radio over fiber link with 4-QAM OFDM modulation format at 40 Gb/s over 150 km SMF is proposed. The 60 GHz millimeter-wave signal is generated by the optical heterodyne method. Coherent detection has been used at the receiver to down-convert millimeter-wave signal to IF band. Introduction of the OFDM modulation in RoF-based system realizes the benefits of higher order modulations (such as 4-QAM, 16-QAM, etc.) to ensure the good spectral efficiency and multi-gigabit access. The performance of the system is analyzed by Q-factor and BER by which it can be shown that the best results are obtained at the input power of 10 dBm. The simulation results clearly demonstrate the feasibility of this 4-QAM OFDM RoF system over 150 km fiber link. 相似文献
997.
Muhammad Rafiq Abuturab 《Journal of Modern Optics》2013,60(11):1035-1050
AbstractA new multiple color-image authentication system based on HSI (Hue–Saturation–Intensity) color space and QR decomposition in gyrator domains is proposed. In this scheme, original color images are converted from RGB (Red–Green–Blue) color spaces to HSI color spaces, divided into their H, S, and I components, and then obtained corresponding phase-encoded components. All the phase-encoded H, S, and I components are individually multiplied, and then modulated by random phase functions. The modulated H, S, and I components are convoluted into a single gray image with asymmetric cryptosystem. The resulting image is segregated into Q and R parts by QR decomposition. Finally, they are independently gyrator transformed to get their encoded parts. The encoded Q and R parts should be gathered without missing anyone for decryption. The angles of gyrator transform afford sensitive keys. The protocol based on QR decomposition of encoded matrix and getting back decoded matrix after multiplying matrices Q and R, enhances the security level. The random phase keys, individual phase keys, and asymmetric phase keys provide high robustness to the cryptosystem. Numerical simulation results demonstrate that this scheme is the superior than the existing techniques. 相似文献
998.
Raz Muhammad Yaseen Iqbal 《Journal of Materials Science: Materials in Electronics》2013,24(7):2322-2326
The effect of K substitution for Na on the phase, microstructure and microwave dielectric properties of the Na1?x K x Ca4Nb5O17 (x = 0–1) composition series was investigated. The compositions with x = 0, 0.5 and 1 formed single-phase Na1?x K x Ca4Nb5O17 ceramics within the detection limit of the in-house XRD facility when sintered at 1,200–1,300 °C. At x = 0.25 and 0.75, the major Na1?x K x Ca4Nb5O17 phase formed but along with a secondary CaNb2O6 phase. Relative permittivity (ε r ) and temperature coefficient of resonant frequency (τf) increased from 45 to 51 and ?120 to +473 ppm/ °C respectively while the quality factor (Q × f o ) decreased from 13,838 to 2,374 GHz with an increase in x from 0 to 1. Optimum microwave dielectric properties (i.e. ε r = 47, Q × f o = 5,047 GHz and τf = ? 23 ppm/ °C) were achieved for the x = 0.5 (i.e. Na0.5K0.5Ca4Nb5O17) composition. Further investigations are required to improve the density and hence microwave dielectric properties of Na1?x K x Ca4Nb5O17 ceramics. 相似文献
999.
Syed Mansoor Ali Jan Muhammad Syed Tajammul Hussain Syed Danish Ali Naeem Ur Rehman Muhammad Hammad Aziz 《Journal of Materials Science: Materials in Electronics》2013,24(12):4925-4931
This study describes the effect of annealing at different temperatures (400–600 °C) on structural, optical and electrical behaviors of pure and Mg doped tin oxide thin films grown on the glass substrate by electron beam evaporation technique. The transformation of tetragonal to orthorhombic form due to annealing, introduced a change in the optical and electrical properties of pure and Mg doped tin oxide thin films. X-ray diffraction studies or analysis revealed the phase transformation and change in the crystalline size with increase in the annealing temperature. The morphology and roughness of the thin films were studied by Atomic force microscopy. Optical band gap increased with annealing temperature confirms the improvements of crystallinity. The quality of thin films transparency was investigated by UV/Vis-spectroscopy. Photoluminescence of pure and Mg doped tin oxide thin films shows two extra peaks one at 486 nm and other at 538 nm is due to the crystal defect created as a result of annealing temperature. These peaks became stronger and shifted to longer wavelength with increasing the annealing temperature. The complex plot (Nyquist plot) showed the data point laying on two semicircles and the resistance of grains and grain boundaries increases with the increase in annealing temperature for both pure and Mg doped tin oxide thin films. 相似文献
1000.
Daniela Hesse Muhammad Badar André Bleich Anna Smoczek Silke Glage Marc Kieke Peter Behrens Peter Paul Müller Karl-Heinz Esser Martin Stieve Nils Kristian Prenzler 《Journal of materials science. Materials in medicine》2013,24(1):129-136
Chronic otitis media is a common disease often accompanied by recurrent bacterial infections. These may lead to the destruction of the middle ear bones such that prostheses have to be implanted to restore sound transmission. Surface coatings with layered double hydroxides (LDHs) are evaluated here as a possibility for drug delivery systems with convenient advantages such as low cytotoxicity and easy synthesis. Male New Zealand White rabbits were implanted with Bioverit® II middle ear prostheses coated with the LDH Mg4Al2(OH)12(SO4)2·6H2O impregnated with ciprofloxacin. 12 (group 1) were directly infected with Pseudomonas aeruginosa and another 12 (group 2) 1 week after the implantation. Clinical outcome, blood counts, histological analyses and microbiological examination showed an excellent antimicrobial activity for group 1, whereas this effect was attenuated in animals where infection was performed 1 week after implantation. This is the first study to demonstrate an efficient drug delivery system with an LDH coating on prostheses in the middle ear. 相似文献