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This paper addresses an efficient modification method that eliminates the undesirable effects of strains due to various non-conforming modes so that the non-conforming element can pass the patch test unconditionally. The scheme is...
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This paper addresses an efficient modification method that eliminates the undesirable effects of strains due to various non-conforming modes so that the non-conforming element can pass the patch test unconditionally. The scheme is incorporated in the element formulation to establish new types of non- conforming hexahedral elements designated as NHx and NVHx for the regular element and variable node element, respectively. Non-conforming displacement modes are selectively behavior of the ordinary (conforming)element displacement assumptions to improve the bending behavior of the distorted solid element.
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RNA modifications have been historically considered as fine-tuning chemo-structural features of infrastructural RNAs, such as rRNAs, tRNAs, and snoRNAs. This view has changed dramatically in recent years, to a large extent as a re...
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RNA modifications have been historically considered as fine-tuning chemo-structural features of infrastructural RNAs, such as rRNAs, tRNAs, and snoRNAs. This view has changed dramatically in recent years, to a large extent as a result of systematic efforts to map and quantify various RNA modifications in a transcriptome-wide manner, revealing that RNA modifications are reversible, dynamically regulated, far more widespread than originally thought, and involved in major biological processes, including cell differentiation, sex determination, and stress responses. Here we summarize the state of knowledge and provide a catalog of RNA modifications and their links to neurological disorders, cancers, and other diseases. With the advent of direct RNA-sequencing technologies, we expect that this catalog will help prioritize those RNA modifications for transcriptome-wide maps.
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For the purpose of this article, experimental phasing is understood to mean the determination of macromolecular structures by exploiting small intensity differences of Friedel opposites and possibly of reflections measured at diff...
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For the purpose of this article, experimental phasing is understood to mean the determination of macromolecular structures by exploiting small intensity differences of Friedel opposites and possibly of reflections measured at different wavelengths or for heavy‐atom derivatives, without the use of specific structural models. The SHELX programs provide a robust and efficient route for routine structure solution by the SAD, MAD and related methods, but involve a number of simplifying assumptions that may limit their applicability in borderline cases. The substructure atoms ( i.e. those with significant anomalous scattering) are first located by direct methods, and the experimental data are then used to estimate phase shifts that are added to the substructure phases to obtain starting phases for the native reflections. These are then improved by density modification and, if the resolution of the data and the type of structure permit, polyalanine tracing. A number of extensions to the tracing algorithm are discussed; these are designed to improve its performance at low resolution. Given native data to 2.5?? resolution or better, a correlation coefficient greater than 25% between the structure factors calculated from such a trace and the native data is usually a good indication that the structure has been solved.
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Mean Radiant Temperature (Tmrt) is a crucial indicator to assess urban radiant and thermal environments. In this study, Tmrt derived from the globe thermometer method and three simulation models (SOLWEIG, RayMan, and ENVI-met) wer...
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Mean Radiant Temperature (Tmrt) is a crucial indicator to assess urban radiant and thermal environments. In this study, Tmrt derived from the globe thermometer method and three simulation models (SOLWEIG, RayMan, and ENVI-met) were analyzed and modified based on the standard six-directional method (Tmrt(six)). Performances of the techniques were compared for two contrasting seasons, summer and winter, and at sites with different degrees of openness. The accuracies of each method were assessed via patterns in time series, coefficient of determination, root mean square error, and Willmott index of agreement. Results showed that globe thermometer method was more suitable for estimating Tmrt in summer than winter, and it showed better performance in more open spaces. The simulation inaccuracies were mainly reflected in winter. Comparatively, SOLWEIG exhibited the best performance in correlation and discrepancy; RayMan presented an advantage in describing the trend consistency of Tmrt than ENVI-met; ENVI-met simulated Tmrt closer to Tmrt(six) than RayMan. Principlebased causes of the techniques' inaccuracies were analyzed. Correlation and cluster analyses were applied for the globe thermometer method, and global radiation showed the strongest correlation and nearest distance with globe temperature, followed by air temperature. Sensitivity and components analyses were utilized for the simulation models involving isotropic and anisotropic issues considering direct and diffuse radiation, solar position, and surrounding environment. Based on the characteristics of different techniques, multiple nonlinear (introducing equivalent globe temperature) and unary linear regressions were utilized to modify globe thermometer and simulation results, respectively. Both modifications significantly improved Tmrt determination accuracies.
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Secret message capacity and stego image quality are the two important measures for stenography. In this paper, a high hiding capacity and acceptable stego image quality steganographic scheme is proposed based on multi-bit encoding...
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Secret message capacity and stego image quality are the two important measures for stenography. In this paper, a high hiding capacity and acceptable stego image quality steganographic scheme is proposed based on multi-bit encoding function. Using our method, the embedding capacity is as high as 4.5 bpp (with acceptable stego image quality, i.e., PSNR better than 30 dB). There are two major contributions of this scheme. It does not need additional complex steps to embed the secret data and no additional external information is needed to recover the secret data. From our experimental results and discussion, we show that our proposed scheme achieves higher capacity than other data hiding schemes based on encoding function while maintaining suitable image quality. (C) 2015 Elsevier GmbH. All rights reserved.
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A new method of combining one-wavelength anomalous scattering (OAS) phasing and density modification has been described, in which the improved phases from density modification are re-introduced into OAS phasing. In this way, the p...
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A new method of combining one-wavelength anomalous scattering (OAS) phasing and density modification has been described, in which the improved phases from density modification are re-introduced into OAS phasing. In this way, the phases could be improved iteratively until convergence. The OAS phasing method is based on the previously established sign-probability formula, which breaks the phase ambiguity in the OAS phasing. The implementation of this method has been available in CCP4 as OASIS. This method, although based on direct-methods, could also incorporate known phases and figures of merit into its sign-probability formula. In the implementation of OASIS, the known phases are from the positions of the anomalous scatters. In the current method, the known phases are from the density modification. The current method was tested on phasing a lysozyme crystal using anomalous scattering of sulphur atoms with diffraction data collected on an in-house x-ray source. The resulting map was well connected for the backbone atoms and clearly traceable, with an average map correlation coefficient of 0.6622 for the backbone atoms.
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Purpose - Local wall thinning is one of serious problems in aged power generating plants. As the thinning grows inside the pipes, it is difficult to detect and evaluate it from the outer surface of pipe. The purpose of this paper ...
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Purpose - Local wall thinning is one of serious problems in aged power generating plants. As the thinning grows inside the pipes, it is difficult to detect and evaluate it from the outer surface of pipe. The purpose of this paper is to evaluate the method of semi-ellipsoidal wall thinning geometry on the back surface of flat plate by direct-current potential difference method (DC-PDM) was proposed as a preliminary research for the pipe wall thinning evaluation. The evaluation was performed for the potential difference numerically obtained by finite element method and the results were discussed. Design/methodology/approach - A number of electric field analyses are necessary to evaluate the geometry of local wall thinning. In this study, defect-current modification method (DCMM), which is very fast analysis method based on the formulated solution for the similar thinning geometry, was used. The DCMM enabled the repeated electric field analyses necessary for the evaluation. Findings - The potential difference on the front surface of plate was higher than the other part because of the electric current disturbance by a wall thinning on the back surface. In addition, the distribution depended on the geometry of the wall thinning. In this study, the shape of the thinning was assumed to be ellipsoid, and the width, depth, and length of the thinning were successfully evaluated based on the potential difference distribution on the front surface. Originality/value - Evaluation of local wall thinning geometry was carried out by repeated analyses using DCMM, and the results were successful. This fact suggests that the evaluation of local wall thinning is possible by DC-PDM. The proposed method is going to be extended to the local wall thinning on the inner surface of pipe by geometrical conversion.
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Non-conforming membrane elements which have variable number of mid-side nodes with drilling degrees of freedom and which is designated as NMDx have been presented in this paper. The non-conforming elements with variable number of ...
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Non-conforming membrane elements which have variable number of mid-side nodes with drilling degrees of freedom and which is designated as NMDx have been presented in this paper. The non-conforming elements with variable number of mid-side nodes can be efficiently used in the local mesh refinement for the in-plane structures. To guarantee the developed elements always pass the patch test, the direct modification method is incorporated into the element formulation. Detailed numerical tests in this study show the validity of the variable node NC elements developed in this study and a wide applicability of these elements to practical problems.
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Biotic indices based on soft-bottom macrozoobenthic communities are currently used throughout Europe to assess the ecological quality of coastal and transitional water bodies according to the European Water Framework Directive. Ho...
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Biotic indices based on soft-bottom macrozoobenthic communities are currently used throughout Europe to assess the ecological quality of coastal and transitional water bodies according to the European Water Framework Directive. However, the performance of the currently available biotic indices still has to be tested against a variety of different impact sources. In particular, physical perturbations have received much less attention than other kind of disturbances. This study consisted in testing the capacity of currently available uni- (BOPA, AMBI and BENTIX) and multivariate (M-AMB1) Biotic Indices to assess the ecological impact of the destruction of a Zostera noltii seagrass bed in Arcachon Bay (France) following sediment deposits. Changes of habitat after this physical perturbation were hardly assessed by any of these Biotic Indices whereas analysis of the benthic community showed drastic changes of structure following the perturbation and no recovery after 15 months. This study demonstrates that these Biotic Indices must be integrated into a multimetric approach which describes better the biological integrity of the benthic community by including a complementary set of metrics. A new multimetric approach, named MISS (Macrobenthic Index of Sheltered Systems) is proposed. MISS correctly highlighted the destruction of the seagrass beds, by using 16 metrics describing the biological integrity of the macrofauna.
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