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61.
In this article, linear programming and fuzzy optimization models are developed for planning and management of available land-water-crop system of Mahanadi-Kathajodi delta in eastern India. The models are used to optimize the economic return, production and labour utilization, and to search the related cropping patterns and intensities with specified land, water, fertilizer and labour availability, and water use pattern constraints. Due to extreme backwardness of the study area, it has been decided to keep all the three objectives of the linear programming models at the same priority level to obtain the compromised solution in a fuzzy environment that incorporates the imprecision in fuzzy goals and fuzzy constraints. These non-structural models facilitate the conjunctive use of available surface water and groundwater resources. A comparative evaluation along with the benefit-cost ratios of the existing and proposed farming systems is also presented.  相似文献   
62.

Position-patch based approaches have been proposed for single-image face hallucination. This paper models the face hallucination problem as a coefficient recovery problem with respect to an adaptive training set for improved noise robustness. The image-adaptive training set is constructed by corrupting a local training set of position-patches by adding specific amounts of noise depending on the input image noise level. In this proposed method, image denoising and super-resolution are simultaneously carried out to obtain superior results. Though the principle is general and can be extended to most super-resolution algorithms, we discuss this in context of existing locality-constrained representation (LcR) approach in order to compare their performances. It can be demonstrated that the proposed approach can quantitatively and qualitatively yield better results in high noisy environments.

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63.
64.
Creating defect tolerant lead‐free halide perovskites is the major challenge for development of high‐performance photovoltaics with nontoxic absorbers. Few compounds of Sn, Sb, or Bi possess ns2 electronic configuration similar to lead, but their poor photovoltaic performances inspire us to evaluate other factors influencing defect tolerance properties. The effect of heavy metal cation (Bi) transmutation and ionic migration on the defects and carrier properties in a 2D layered perovskite (NH4)3(Sb(1?x)Bix)2I9 system is investigated. It is shown, for the first time, the possibility of engineering the carriers in halide perovskites via metal cation transmutation to successfully form intrinsic p‐ and n‐type materials. It is also shown that this material possesses a direct–indirect bandgap enabling high absorption coefficient, extended carrier lifetimes >100 ns, and low trap densities similar to lead halide perovskites. This study also demonstrates the possibility of electrical poling to induce switchable photovoltaic effect without additional electron and hole transport layers.  相似文献   
65.
Efficient modal decomposition of high-dimensional turbulent flow data is an important first step for data reduction, analysis, and low-dimensional predictive modeling. The conventional modal decomposition techniques, such as proper orthogonal and dynamic mode decompositions, aim to represent the system response using spatially global basis vectors that span a broad spatial domain. A significant challenge facing approaches based on global domain decomposition is the rapid increase in both the amount of training data and the number of modes that must be retained for an accurate representation of convection dominated turbulent flows. An alternative generalized finite element (GFEM) based approach is explored for efficient representation of high-dimensional fluid flow data. Here, the standard finite element interpolation method is enriched with numerical functions that are learned from a small amount of high-fidelity training data over spatially localized subdomains. The GFEM approach is demonstrated on a 3D flow past a cylinder at Reynolds number of 100 000 and flows inside a 2D lid-driven cavity over a range of Reynolds numbers. Compared with a global proper orthogonal decomposition, the GFEM-based approach increases efficiency in reconstructing the datasets while also substantially reducing the amounts of training data.  相似文献   
66.
Sandwiched structures comprising Pt/Co/Pt layers with varying cobalt deposition time was studied and its importance on the alloy composition, by correlating the effective interlayer diffusion with the atomic stoichiometry, has been presented. A structural phase transition from ordered L12 CoPt3 –? L10 CoPt –? L12 Co3Pt was observed with increasing Co deposition time after annealing at 700 °C. The cross-sectional SEM image of the as-deposited film clearly shows a cobalt layer sandwiched between platinum layers. Rutherford back scattering (RBS) analysis shows a multipeak signature for the as-deposited films. A detailed RBS investigation on the extent of interatomic diffusion reveals an equiatomic composition for 20 and 30 min deposition time after annealing. The equiatomic CoPt phase shows a magnetically hard behaviour with a maximum coercivity of 15000 Oe. The reported dependence of (BH)max on coercivity concludes that by tailoring an additional parameter of deposition time, diverse combinations of structural and magnetic properties can be achieved for appropriate practical applications.  相似文献   
67.
The purpose of this study was to evaluate the influences of intrinsic drug mechanical properties and different granulation binder delivery processes on the physical and mechanical properties of high drug load granulations after wet granulation. Formulations (80% w/w) of acetaminophen (APAP), metformin and aspirin, which are brittle, viscoelastic, and ductile, respectively; were granulated by high-shear wet granulation. Two modes of binder delivery for wet granulation, either conventional or binder foam, were investigated. Particle size, surface area and pore size of the granulations were characterized. Compacts were prepared at a solid fraction of 0.9 under tri-axial decompression and Hiestand indices (worst-case bonding index (BIw) and brittle fracture index (BFI)) of the compacts were determined. APAP formulations exhibited the smallest geometric mean particle sizes (dg) and showed only slight differences in dg values between the two granulation processes. Binder delivery mode affected mechanical properties of the granulated model drugs differently. Foam granulation appeared to enhance the granule plasticity for APAP while aspirin showed a mixed deformation mechanism based on both its high BIw and high BFI values. The higher BIw value for aspirin after foam granulation may be attributed to improved binder distribution among particles during granulation. On the other hand, conventional wet granulation improved the plasticity of metformin as measured by the higher BIw and lower BFI values. Therefore, conventional wet granulation process conferred advantages in manufacturability and product quality for metformin; as compared to foam granulation which did not enhance plasticity for metformin. Based on this study, a wet granulation process can be selected based on knowledge of the intrinsic drug mechanical properties.  相似文献   
68.
Generation of electrical energy from wind can be economically achieved only where a significant wind resource exists. Because of the cubic relationship between wind velocity and output energy, sites with small percentage differences in average wind speeds can have substantial differences in available energy. Therefore, accurate and thorough monitoring of wind resource at potential sites is a critical factor in the siting of wind turbines. An accurately measured wind-speed frequency spectrum at a site is another important factor. For assessment of the wind-power potential of a site, most investigators have used simple wind-speed distributions that are parametrized solely by the arithmetic mean of the wind speed. Assessment of power output of a wind turbine will be accurate if the wind speeds measured at the hub height (30–50 m) of a wind turbine-generator are known. However, the existing wind data available at most of the meteorological stations worldwide is measured at a height of 10 or 20 m above the ground. Therefore, wind speeds measured at anemometer heights are extrapolated to the hub height of the wind turbine. Many investigators have proposed simple expressions for height extrapolation of wind speeds. This paper reviews wind-speed prediction and forecasting, and development of techniques for accurate assessment of wind-power potential. Also, the need of wind-resource assessment and the techniques and methods used for it are highlighted.  相似文献   
69.
We correlate thelevel of knowledge of certain formulas in agroup of individuals with certain regular, downward closed, sets of strings. We show that in suitable circumstances, all such sets can occur as levels of knowledge but that the lack of synchrony, or the lack of asynchrony when there are only two processors in the group, can create more or less severe restrictions.  相似文献   
70.
The kinetics of the heterogeneous reaction between hydrogen and aqueous solutions of D -glucose to produce sorbitol were studied in a high pressure Parr reactor. Raney-Ni was used as catalyst. The reaction between hydrogen and D -glucose was found to be very slow. In the agitated slurry reactor the diffusional aspects were completely eliminated and the reaction followed homogeneous kinetics. It was found to be first order with respect to both hydrogen and D -glucose. The values of the pseudo-first-order rate constants were found to be 1.5 × 10?4 and 6.4 × 10?4s?1 at 398 and 435 K, respectively. The activation energy was found to be 64.8 kJ mol?1.  相似文献   
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