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21.
P.?JindalEmail author H.?J.?Kaur 《Optoelectronics, Instrumentation and Data Processing》2018,54(6):576-581
Nano-photonics is an emerging area of optical materials, which would take the optointegrated circuits towards progress. Photonic crystal (PC) based power splitters are useful constituents for the design of photonic integrated circuits (PICs). They are very important devices for connecting different building blocks on an integrated optical chip. In this paper, a two-dimensional PC Y-junction power splitter (21×15 μm) based on the resonance effect with circular air holes etched on a hexagonal lattice with a period a is proposed. The plane wave expansion (PWE) and finite difference time domain (FDTD) techniques are used for analyzing the structure. The simulation results show that the optimum resonance occurs when the radius of the defect hole is 0.3a, leading to the maximum and equal power distribution. 相似文献
22.
Prabhjot Kaur A.K. Soni Anjana Gosain 《Engineering Applications of Artificial Intelligence》2013,26(2):833-847
A new data clustering algorithm Density oriented Kernelized version of Fuzzy c-means with new distance metric (DKFCM-new) is proposed. It creates noiseless clusters by identifying and assigning noise points into separate cluster. In an earlier work, Density Based Fuzzy C-Means (DOFCM) algorithm with Euclidean distance metric was proposed which only considered the distance between cluster centroid and data points. In this paper, we tried to improve the performance of DOFCM by incorporating a new distance measure that has also considered the distance variation within a cluster to regularize the distance between a data point and the cluster centroid. This paper presents the kernel version of the method. Experiments are done using two-dimensional synthetic data-sets, standard data-sets referred from previous papers like DUNN data-set, Bensaid data-set and real life high dimensional data-sets like Wisconsin Breast cancer data, Iris data. Proposed method is compared with other kernel methods, various noise resistant methods like PCM, PFCM, CFCM, NC and credal partition based clustering methods like ECM, RECM, CECM. Results shown that proposed algorithm significantly outperforms its earlier version and other competitive algorithms. 相似文献
23.
Results on an investigation dealing with the effect of metakaolin (MK) on the near surface characteristics of concrete are presented in this paper. A control concrete having cement content 450 kg/m3 and w/c of 0.45 was designed. Cement was replaced with three percentages (5, 10, and 15%) of metakaolin weight. Tests were conducted for initial surface absorption, sorptivity, water absorption and compressive strength at the ages of 35, 56, and 84 days. Test results indicated that with the increase in MK content from 5 to 15%, there was a decrease in the initial surface absorption, decrease in the sorptivity till 10% metakaolin replacement. But at 15% MK replacement an increase in sorptivity was observed. All mixtures showed low water absorption characteristic i.e. less than 10%. Compressive strength shared an inverse relation with sorptivity. Higher MK replacements of 15% are not helpful in improving inner core durability, even though it helps in improving surface durability characteristics. 相似文献
24.
R. R. Kaur D. R. Swinbourne M. W. Wadsley C. Nexhip 《Metallurgical and Materials Transactions B》2011,42(3):451-459
The cost of maintaining and eventually replacing refractories as a result of slag attack is a significant cost component in the copper industry. Converting matte to blister copper takes place in reactors lined with direct-bonded magnesia-chrome refractories, and several continuous converting operations use calcium ferrite slag. Unfortunately, the low viscosity of calcium ferrite slag makes it aggressive toward the refractories. Ferrous calcium silicate (FCS) slag has been proposed as a replacement; however, the effect of this slag on magnesia-chrome refractories has not been studied. In this work, the interactions between FCS slag and magnesia-chrome refractory at 1573 K (1300 °C) with an oxygen partial pressure of 10−6 atm were studied and compared with that experienced with calcium ferrite slag under the same conditions. Both slags penetrated the pores in the refractory and caused compositional change in the chromite spinel intergranular bonding phase through cation interdiffusion, which resulted in cracking and debonding of periclase grains. It was observed that the refractory was penetrated much more deeply by calcium ferrite slag than FCS slag because of the higher surface tension and lower viscosity of calcium ferrite slag. As a result, the refractory was attacked less by FCS slag than it was by calcium ferrite slag. It is concluded that the use of FCS slag in continuous copper converting is likely to extend refractory life. 相似文献
25.
ZnO and In2O3 films were prepared by thermal oxidation of vacuum deposited zinc and indium films, respectively onto the glass substrate at 30 C. The fabricated films have been irradiated with 100-MeV Ni7+ ions at different fluences ranging from 5×1011 to 5×1013 ions/cm2. The structural and gas sensing properties of pristine and irradiated films have been discussed. X-ray diffraction (XRD) pattern of pristine and irradiated films reveal that the films are polycrystalline in nature and crystallinity increases after irradiation. In this study, highly porous In2O3 nanorods evolved when being irradiated at a fluence of 5×1013 ions/cm2 while ZnO film shows decrease in number of nanowires. The ammonia sensing performance of the Ni7+ irradiated In2O3 films shows an improvement as compared to its pristine counterpart. 相似文献
26.
Rajinder Kaur 《Particulate Science and Technology》2015,33(1):76-80
Coal fly ash procured from Guru Gobind Singh Super Thermal Power Plant, Ropar, Punjab, India, was analyzed for its mineralogical content and thermal stability by x-ray diffraction (XRD), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and physicochemical properties. XRD studies showed that major crystalline phases observed were quartz (SiO2) and aluminum silicon oxide (Al4.52Si1.48) with macro- and microelement (N, P, K, Mg, Zn, S, and Fe). Fly ash showed thermal stability up to 500°C and reduction in weight was up to 200°C, primarily due to loss of water and decarboxylation as revealed by TGA plots. FTIR of fly ash showed that the most prominent peaks in the spectra corresponded to Si–O and Al–O stretch vibrations. Coarse-grain accumulation of fly ash indicated the presence of 70% of fine-grained particles of 0.075 mm. Coal fly ash was alkaline in nature (pH 7.85 ± 0.03) with an electrical conductivity of 0.14 ± 0.02 µS m?1, water holding capacity of 62%, low bulk density of 0.99 g cm?3, and a surface area of 0.96 m2 g?1. With properties similar to that of soil coal, fly ash represents a suitable material for use in specific quantities as a soil amending agent in agriculture. 相似文献
27.
Increased incidence of immunosuppression due to diseases like AIDS, drug resistant tuberculosis, malaria or exposure to chemicals, calls for general immunopotentiators or anti immunosuppressents. In our previous work while screening the chemical and biopesticides for their immunopotentiating activity, aqueous leaves extract of bio‐pesticidal plant Nyctanthes arbor‐tristis [HL(aq)] was found to be a potent immuno‐modulator. The present study was conducted to evaluate the immunorestorative or anti immunosuppressive activity of the N. arbor‐tristis leaves aqueous extract in the malathion exposed immunosuppressed mice. The immunorestorative potential of HL(aq) was evaluated by studying various immunological parameters (humoral, cell mediated immune, numerical values of immunocytes and functions of phagocytes) in HL(aq) treated or untreated malathion‐exposed mice. The results revealed that the immunological parameters which were suppressed with malathion either reverted back to normal or showed a trend towards normalacy, when treated with HL(aq) extract. 相似文献
28.
Thin films of CdSe and silver(Ag)-doped CdSe have been prepared on glass substrates by thermal evaporation in argon gas atmosphere. X-ray diffraction pattern indicates the presence of hexagonal structure with preferred orientation along (100) plane. Elemental composition of the thin films has been analyzed using energy dispersive X-ray analysis. Scanning electron microscopy has been used to investigate the morphology of the thin films. Transmission electron microscope reveals spherical nature of nanoparticles. A decrease in the band gap due to the formation of band tails in the band gap with increase in Ag doping in CdSe lattice has been observed. Photoluminescence spectra indicate redshift in band edge emission peak with increase in Ag doping in CdSe. Electrical conductivity measurements are also studied, and two types of conduction mechanisms taking part in the transport phenomena are observed. Hall measurements indicate n-type behavior of undoped and Ag-doped CdSe thin films. 相似文献
29.
The article presents a working model of Control rod insertion in nuclear power plant based on fuzzy logic and implemented with MC68HC11 microcontroller. The control rods are made of neutron absorbing metal. The amount of control rod insertion into a pressurized water reactor in a nuclear power plant controls the nuclear fission process by controlling the rate at which the chain reaction takes place. The temperature in the pressurized water tank varies with the load of power, the higher the demand of power the higher the temperature and vice versa. The control rods help to maintain the appropriate temperature in the core of the reactor. Nuclear Power plants use a very complicated control scheme, to vary the amount of control rod insertion which is very expensive and difficult to troubleshoot. We have developed a fuzzy model, tested its functionality by generating control surfaces, written the fuzzy inference software, downloaded in the EEPROM of MC68HC11, and interfaced it with 8 LED Bar to simulate control rod and two 8-bit DIP switches to enter inputs of Power Generation and Temperature of the core of the reactor. © 1996 John Wiley & Sons, Inc. 相似文献
30.
Tania Bakshi David Pham Raminderjeet Kaur Bingyun Sun 《International journal of molecular sciences》2022,23(7)
N-Glycosylation (NG) and disulfide bonds (DBs) are two prevalent co/post-translational modifications (PTMs) that are often conserved and coexist in membrane and secreted proteins involved in a large number of diseases. Both in the past and in recent times, the enzymes and chaperones regulating these PTMs have been constantly discovered to directly interact with each other or colocalize in the ER. However, beyond a few model proteins, how such cooperation affects N-glycan modification and disulfide bonding at selective sites in individual proteins is largely unknown. Here, we reviewed the literature to discover the current status in understanding the relationships between NG and DBs in individual proteins. Our results showed that more than 2700 human proteins carry both PTMs, and fewer than 2% of them have been investigated in the associations between NG and DBs. We summarized both these proteins with the reported relationships in the two PTMs and the tools used to discover the relationships. We hope that, by exposing this largely understudied field, more investigations can be encouraged to unveil the hidden relationships of NG and DBs in the majority of membranes and secreted proteins for pathophysiological understanding and biotherapeutic development. 相似文献