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111.
This study investigated the external contributors of library and information science (LIS) knowledge who were unaffiliated with LIS-related institutions but published their research results in LIS journals. Differences between the contributors to library science (LS) and contributors to information science (IS) were considered. Articles published in 39 strongly LIS-oriented journals indexed in the Web of Science database between 2005 and 2014 were analyzed. The results demonstrated that 46.5% of the LIS articles were written by at least one non-LIS author; authors’ backgrounds ranged across 29 disciplines. An increasing trend was observed in degrees of interdisciplinarity of LS and IS. An increase in proportion of articles by LIS and non-LIS authors was identified in LS and IS as well. Those with medical backgrounds were the primary non-LIS authors contributing to the LS field and collaborated the most frequently with LIS authors. Those with computer science backgrounds were the most prevalent non-LIS contributors to the IS field and preferred to publish individually. A critical difference was also identified in research topics between LS and IS. The foundations of LIS and scientometrics were the largest research topics in LS and IS, respectively.  相似文献   
112.
Optimization and Engineering - Multidomain mixed pairs of coupled stationary constrained boundary value problems, are formulated variationally in frameworks of reflexive Banach spaces as...  相似文献   
113.
Solid‐state nanopores are fascinating objects that enable the development of specific and efficient chemical and biological sensors, as well as the investigation of the physicochemical principles ruling the behavior of biological channels. The great variety of biological nanopores that nature provides regulates not only the most critical processes in the human body, including neuronal communication and sensory perception, but also the most important bioenergetic process on earth: photosynthesis. This makes them an exhaustless source of inspiration toward the development of more efficient, selective, and sophisticated nanopore‐based nanofluidic devices. The key point responsible for the vibrant and exciting advance of solid nanopore research in the last decade has been the simultaneous combination of advanced fabrication nanotechnologies to tailor the size, geometry, and application of novel and creative approaches to confer the nanopore surface specific functionalities and responsiveness. Here, the state of the art is described in the following critical areas: i) theory, ii) nanofabrication techniques, iii) (bio)chemical functionalization, iv) construction of nanofluidic actuators, v) nanopore (bio)sensors, and vi) commercial aspects. The plethora of potential applications once envisioned for solid‐state nanochannels is progressively and quickly materializing into new technologies that hold promise to revolutionize the everyday life.  相似文献   
114.
This research presents a technique to quantify morphological damage to flutes in corrugated fibreboard (CFB). The method involves laser cutting thin samples and analysing digital images of the flute profiles. The surface profiles of creased CFB before and after laser cutting were measured using fringe projection and showed that the sample preparation does not significantly affect the flute profile. After imaging the laser cut samples, skeleton analysis was used to derive a digitised profile of the flute shape. To characterise the level of damage to the flute profile, a similarity factor (SF) was introduced to quantify the relative difference between test sample and reference flute profiles. Validation of this analysis technique was done by generating known images of flute profile with variations that include distortions that could occur to CFB. These images were then fed into the skeleton analysis, and the results were compared with the original profile. This comparison showed good agreement between the initial and skeleton‐analysed flutes. A demonstration of the skeleton analysis on purposefully damaged actual CFB flute profiles shows that the SF reduces as the level of crushing increases, showing that the technique could be used to enumerate morphological damage to CFB during manufacture, conversion, and use.  相似文献   
115.
Neural Computing and Applications - This work presents the uncertainty analysis of an artificial neural network (ANN)-based method, called multiharmonic ANN fitting method (MANNFM), which is able...  相似文献   
116.
We analyse instabilities due to aliasing errors when solving one dimensional non-constant advection speed equations and discuss means to alleviate these types of errors when using high order discontinuous Galerkin (DG) schemes. First, we compare analytical bounds for the continuous and discrete version of the PDEs. Whilst traditional \(L^2\) norm energy bounds applied to the discrete PDE do not always predict the physical behaviour of the continuous version of the equation, more strict elliptic norm bounds correctly bound the behaviour of the continuous PDE. Having derived consistent bounds, we analyse the effectiveness of two stabilising techniques: over-integration and split form variations (conservative, non-conservative and skew-symmetric). Whilst the former is shown to not alleviate aliasing in general, the latter ensures an aliasing-free solution if the splitting form of the discrete PDE is consistent with the continuous equation. The success of the split form de-aliasing is restricted to DG schemes with the summation-by-parts simultaneous-approximation-term properties (e.g. DG with Gauss–Lobatto points). Numerical experiments are included to illustrate the theoretical findings.  相似文献   
117.
Sodium carbonate and carboxymethyl cellulose powders are compressed into two-component tablets with three mass ratios, 97%:3%, 95%:5% and 93%:7%. The dissolution tests for two-component tablets and reference pure sodium carbonate tablets are carried out at various temperatures. The dissolution process of each tablet is measured by electrical conductivity tracking method and the concentration of dissolved sodium carbonate is quantified with calibrated conductivity-concentration converting equation of sodium carbonate. The quantified dissolution data is fitted with both surface reaction model and diffusion layer model and the results clearly show that surface reaction model is suggested as the appropriate dissolution model for all measured tablets. Therefore, it is determined that carboxymethyl cellulose is a stable element to remain the dissolution mechanism of tablet unchanged. The dissolution rate constant quantified with surface reaction model presents that carboxymethyl cellulose-sodium carbonate two-component tablets obtain significant higher dissolution rate constant than pure sodium carbonate tablet and higher proportion of carboxymethyl cellulose leads to apparent higher dissolution rate constant. The results prove for the usage of carboxymethyl cellulose in most practical applications at a relative low-level, the effect of carboxymethyl cellulose is effective and positive for two-component tablet to enhance the dissolution process and improve dissolution rate constant and this effect is speculated coming from its dynamic physical transforming process in water including dilation and conglutination.  相似文献   
118.
A new numerical approach to efficiently reconstruct the profile of a grating from measurements of reflection coefficients is demonstrated. The problem is posed in the mathematical framework of an inverse scattering problem and solved using gradient-based algorithms. The gradient is computed efficiently using adjoint equations, which amounts to an extra scattering computation per iteration. For symmetric profiles it is shown that only knowledge of the scattered field is sufficient to compute the gradient. As a result, complex profiles can be reconstructed rapidly, and the method can be potentially used in metrology applications in semiconductors. The technique is demonstrated for the case of TE polarization.  相似文献   
119.
Using ultrafast spectroscopy, we investigated electron-lattice coupling and acoustic vibrations in self-assembled silver nanocolumns embedded in an amorphous Al2O3 matrix. The measured electron-lattice energy exchange time is smaller in the nanocolumns than in bulk silver, with a value very close to that of isolated nanospheres with comparable surface to volume ratio. Two vibration modes were detected and ascribed to the breathing and extensional mode of the nanocolumns, in agreement with numerical simulations.  相似文献   
120.
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