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Gupta  Rainy  Bhardwaj  Pooja  Deshmukh  Kumud  Mishra  Deepti  Prasad  Murari  Amritphale  Sudhir S. 《SILICON》2019,11(1):221-232
Silicon - In this study, an innovative one part, solution free concept applied for the development of hybrid inorganic–organic geopolymeric precursors having Si-O-Al networks at the precursor...  相似文献   
23.
Biocomposite scaffolds composed of PVA, ovalbumin, cellulose nanocrystals, and nanohydroxyapatite were fabricated by freeze-drying method. The results revealed that the different fractions of nanohydroxyapatite and cellulose nanocrystals provide the mechanical strength and stiffness to the desired biocomposite scaffolds. In vitro biomineralization showed the formation of apatite onto the surface of obtained biocomposite scaffolds and increased as amount of nanohydroxyapatite increased. The obtained results suggest that the different combinations of these four biomaterials can be used to fabricate highly porous scaffolds with desired mechanical performance and degradation rate by adjusting ratio for potential use in low load-bearing applications.  相似文献   
24.
Flexible lead‐free high energy radiation shielding material was developed through internal compounding. Polymer‐filler interaction, crosslinking density, specific gravity, physicomechanical characteristics, percentage attenuation, and thermal stability of the crosslinked composites were estimated. It was found that even at very high filler loading composites can be crosslinked; however, the crosslinking density was composition dependent and was highest in 10–50 wt% loading range at 100 kGy and 200 kGy. The Nielsen model was applied to understand the micromechanics of the system. Attenuation of gamma radiation from Am241 was not affected by the crosslinking density. Thermal stability of the composites was found to be significantly affected with bismuth oxide loading. POLYM. COMPOS., 37:756–762, 2016. © 2014 Society of Plastics Engineers  相似文献   
25.
Prime movers of enterprise innovation are inside the organisation. The enterprise NIIT, studied in this paper, tells us how elicitation and recognition of knowledge and its contents set an enterprise on the move. Recognised knowledge is actionable. Each act of recognition is an addition to knowledge content, and such additions took place in NIIT through acts of communications and self-searching. These contents form a large collage that cannot be strewn into a single novelistic episode. Perspectives and context, motives and suggestions render to each member of the enterprise different disjoint appearances of knowledge. There are thus many knowledge systems and multiple narrations, each with small episode-like finality. Enterprise innovation is achieved not through any grand episodic integration of all knowledge contents, but by constructively eliciting further new contents of knowledge, and encouraging acts of communications and discourses on this new knowledge. Constructive management of knowledge and communication towards enterprise innovation has thus been defined. Through such constructive management, NIIT enabled itself innovationally and empowered its members in eliciting knowledge and acting communicatively. A critical feature of knowledge work is that it requires multidisciplinary expertise and mutual learning in order to achieve a complex synthesis of highly specialised state-of-the-art technologies and knowledge domains. A convivial work culture and a culture of communicative acts enable sharing of the non-informatised yet recognised contents of knowledge.  相似文献   
26.
Wave-equation-based forward modelling using explicit finite-difference methods is a standard technique for calculating synthetic seismograms. The stability criterion restricts the size of the time step. In this paper a predictor–corrector method for solving the wave equation is described which allows the use of a larger time step. A stability analysis of the method is also carried out. Parallel implementation of the algorithm is described for a distributed computing environment which makes use of MPI and PVM message passing calls for communication between processors.  相似文献   
27.
A new paradigm, which models the relationships between handwriting and topic categories, in the context of medical forms, is presented. The ultimate goals are: (1) a robust method which categorizes medical forms into specified categories, and (2) the use of such information for practical applications such as an improved recognition of medical handwriting or retrieval of medical forms as in a search engine. Medical forms have diverse, complex and large lexicons consisting of English, Medical and Pharmacology corpus. Our technique shows that a few recognized characters, returned by handwriting recognition, can be used to construct a linguistic model capable of representing a medical topic category. This allows (1) a reduced lexicon to be constructed, thereby improving handwriting recognition performance, and (2) PCR (Pre-Hospital Care Report) forms to be tagged with a topic category and subsequently searched by information retrieval systems. We present an improvement of over 7% in raw recognition rate and a mean average precision of 0.28 over a set of 1,175 queries on a data set of unconstrained handwritten medical forms filled in emergency environments. This work was supported by the National Science Foundation.  相似文献   
28.
With the ever-increasing growth of the World Wide Web, there is an urgent need for an efficient information retrieval system that can search and retrieve handwritten documents when presented with user queries. However, unconstrained handwriting recognition remains a challenging task with inadequate performance thus proving to be a major hurdle in providing robust search experience in handwritten documents. In this paper, we describe our recent research with focus on information retrieval from noisy text derived from imperfect handwriting recognizers. First, we describe a novel term frequency estimation technique incorporating the word segmentation information inside the retrieval framework to improve the overall system performance. Second, we outline a taxonomy of different techniques used for addressing the noisy text retrieval task. The first method uses a novel bootstrapping mechanism to refine the OCR’ed text and uses the cleaned text for retrieval. The second method uses the uncorrected or raw OCR’ed text but modifies the standard vector space model for handling noisy text issues. The third method employs robust image features to index the documents instead of using noisy OCR’ed text. We describe these techniques in detail and also discuss their performance measures using standard IR evaluation metrics.  相似文献   
29.
Cloud computing is becoming a profitable technology because of it offers cost-effective IT solutions globally. A well-designed task scheduling algorithm ensures the optimal utilization of clouds resources and reducing execution time dynamically. This research article deals with the task scheduling of inter-dependent subtasks on unrelated parallel computing machines in a cloud computing environment. This article considers two variants of the problem-based on two different objective function values. The first variant considers the minimization of the total completion time objective function while the second variant considers the minimization of the makespan objective function. Heuristic and meta-heuristic (HEART) based algorithms are proposed to solve the task scheduling problems. These algorithms utilize the property of list scheduling algorithm of unrelated parallel machine scheduling problem. A mixed integer linear programming (MILP) formulation has been provided for the two variants of the problem. The optimal solution is obtained by solving MILP formulation using A Mathematical Programming Language (AMPL) software. Extensive numerical experiments have been performed to evaluate the performance of proposed algorithms. The solutions obtained by the proposed algorithms are found to out-perform the existing algorithms. The proposed algorithms can be used by cloud computing service providers (CCSPs) for enhancing their resources utilization to reduce their operating cost.  相似文献   
30.
The structure of noncrystalline, chemically vapour-deposited boron fibres was investigated by computer modelling the experimentally obtained X-ray diffraction patterns. The diffraction patterns from the models were computed using the Debye scattering equation. The modelling was done utilizing the minimum nearest-neighbour distance, the density of the model, and the broadening and relative intensity of the various peaks as boundary conditions. The results suggest that the fibres consist of a continuous network of randomly oriented regions of local atomic order, about 2 nm in diameter, containing boron atoms arranged in icosahedra. Approximately half of these regions have a tetragonal structure and the remaining half a distorted rhombohedral structure. The model also indicates the presence of many partial icosahedra and loose atoms not associated with any icosahedra. The partial icosahedra and loose atoms indicated in the present model are in agreement with the relaxing sub-units which have been suggested to explain the anelastic behaviour of fibre boron and the loosely bound boron atoms which have been postulated to explain the strengthening mechanism in boron fibres during thermal treatment.  相似文献   
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