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1.
ALCHEMIST is a general purpose transformation generating environment, which supports specification, generation and execution of data transformations. ALCHEMIST allows an abstract specification of the transformation through a window-based interface and supports the generation and compilation of transformation program code from these specifications. Unlike compiler-compilers, ALCHEMIST is intended to automate building transformations between two complex representation formats and is thus especially suitable for constructing transformations between database tools, CASE tools, graphical editors or text formatters. In this paper we describe the design principles and the structure of ALCHEMIST, and demonstrate its use. We also discuss our experiences with several example transformations and present a real-life case study of using ALCHEMIST for interfacing two software development environments.  相似文献   
2.
Replication has typically been used as a strategy in chain businesses such as McDonald's where the technology involved is rather simple but it has also been used for very complex technologies where strict quality conditions apply. This paper examines the use of replication when the object of the replication is relatively complex. — i.e. it is neither simple nor very complex. Using a qualitative, embedded single-case study we examine a strategic R&D and capital investment programme aimed at providing a small oil company with first mover advantage in the emerging market for biodiesel. The paper builds on concepts of project capability building, learning and replication and extends previous work which focused on project supplier organisations seeking to deliver similar projects to a range of clients on a repeatable basis by focusing on the efforts of a single client organisation attempting to deliver a series of similar investment projects.  相似文献   
3.
Cellular retinaldehyde-binding protein (CRALBP) carries 11-cis-retinal and/or 11-cis-retinol as endogenous ligands in the retinal pigment epithelium (RPE) and Müller cells of the retina and has been linked with autosomal recessive retinitis pigmentosa. Ligand interactions determine the physiological role of CRALBP in the RPE where the protein is thought to function as a substrate carrier for 11-cis-retinol dehydrogenase in the synthesis of 11-cis-retinal for visual pigment regeneration. However, CRALBP is also present in optic nerve and brain where its natural ligand and function are not yet known. We have characterized the interactions of retinoids with native bovine CRALBP, human recombinant CRALBP (rCRALBP) and five mutant rCRALBPs. Efforts to trap and/or identify a Schiff base in the dark, under a variety of reducing, denaturing, and pH conditions were unsuccessful, suggesting the lack of covalent interactions between CRALBP and retinoid. Buried and solvent-exposed lysine residues were identified in bovine CRALBP by reductive methylation of the holoprotein followed by denaturation and reaction with [3H]acetic anhydride. Radioactive lysine residues were identified by Edman degradation and electrospray mass spectrometry following proteolysis and purification of modified peptides. Human rCRALBP mutants K152A, K221A, and K294A were prepared to investigate possible retinoid interactions with buried or partially buried lysines. Two other rCRALBP mutants, I162V and Q210R, were also prepared to identify substitutions altering the retinoid binding properties of a random mutant. The structures of all the mutants were verified by amino acid and mass spectral analyses and retinoid binding properties evaluated by UV-visible and fluorescence spectroscopy. All of the mutants bound 11-cis-retinal essentially like the wild type protein, indicating that the proteins were not grossly misfolded. Three of the mutants bound 9-cis-retinal like the wild type protein; however, Q210R and K221A bound less than stoichiometric amounts of the 9-cis-isomer and exhibited lower affinity for this retinoid relative to wild type rCRALBP. Residues Gln-210 and Lys-221 are located within a region of CRALBP exhibiting sequence homology with the ligand binding cavity of yeast phosphatidylinositol-transfer protein. The data implicate Gln-210 and Lys-221 as components of the CRALBP retinoid binding cavity and are discussed in the context of ligand interactions in structurally or functionally related proteins with known crystallographic structures.  相似文献   
4.
BACKGROUND: Growth retardation has been reported in children with chronic inflammatory bowel disease, especially in those with Crohn's disease. Most of these studies concern adolescent patients. METHODS: The growth of 47 prepubertal children (20 boys and 27 girls, mean age at diagnosis 7 years) with inflammatory bowel disease was studied at Tampere University Hospital, Department of Paediatrics. The mean height and height velocity standard deviation scores were calculated at diagnosis and, after that, yearly. The cumulative doses of oral and rectal prednisone per year were calculated. The severity of the disease was scored. The statistical analysis was carried out using the analysis of variance for repeated measurements. RESULTS: During the year preceding the diagnosis, children with inflammatory bowel disease had grown more slowly than their healthy peers. At diagnosis, they were slightly shorter as a group than are healthy children. During treatment and follow-up the mean height velocity of children with inflammatory bowel disease increased (change in the mean height velocity standard deviation scores from -0.84 to +1.08), normalizing the mean heights of these children compared with those of their healthy peers (change in the mean height standard deviation scores from -0.32 to +0.05). In the analysis of covariance, the poorest growth was seen in children with Crohn's disease, scored as severe, and the best growth in children with mild ulcerative colitis. No difference was seen in groups with or without prednisone treatment. CONCLUSIONS: Growth retardation is an important sign of chronic inflammatory bowel disease in prepubertal as well as adolescent children. During treatment, increasing growth velocity brings these children as a group to normal heights for age and sex.  相似文献   
5.
Beer‐spoiling lactic acid bacteria (LAB) belong to the most harmful contaminants in the brewing industry and various rapid molecular detection methods have been introduced for the detection of these organisms. However, the enrichment cultivation steps needed prior to detection by molecular methods can extend the duration of the analytical procedure by up to several days. The use of brewery‐specific enrichment cultivation media has been recommended due to the large variety within the group of LAB, as well as differences in the microbes encountered at the breweries. In contrast to using a general medium that may support only the growth of some LAB, the combination of several media could allow detection of all relevant LAB. The aim of the present study was to show the effects of shifts in the cultivation conditions and media on the growth of beer‐spoiling LAB using one of the most frequently encountered species, Pediococcus damnosus, as an example. Based on the variable analysis, significant factors could be recognized and their effects on lag‐times and growth rates were compared by means of response surface modelling.  相似文献   
6.
Differential evolution has become one of the most widely used evolutionary algorithms in multiobjective optimization. Its linear mutation operator is a simple and powerful mechanism to generate trial vectors. However, the performance of the mutation operator can be improved by including a nonlinear part. In this paper, we propose a new hybrid mutation operator consisting of a polynomial-based operator with nonlinear curve tracking capabilities and the differential evolution’s original mutation operator, for the efficient handling of various interdependencies between decision variables. The resulting hybrid operator is straightforward to implement and can be used within most evolutionary algorithms. Particularly, it can be used as a replacement in all algorithms utilizing the original mutation operator of differential evolution. We demonstrate how the new hybrid operator can be used by incorporating it into MOEA/D, a winning evolutionary multiobjective algorithm in a recent competition. The usefulness of the hybrid operator is demonstrated with extensive numerical experiments showing improvements in performance compared with the previous state of the art.  相似文献   
7.
Using a new prototype (Olympus XPGIF 5.2/ N30) gastroscope, upper gastrointestinal endoscopy was safely performed under sedation on 99 infants (weights 0.9 to 10.1 kg). No complications occurred. Macroscopic and microscopic abnormalities were found in 60%, including abnormal duodenal biopsies in 47% of cases with protracted diarrhoea. Duodenal biopsy material was, however, of suboptimal standard for histologic assessment in 25% of the cases. In 52% of those under 3.5 kg diagnoses were made that would not have otherwise been possible and, in 75% of those in the Intensive Care Unit, abnormalities were found. The use of this new endoscope represents a significant advance in clinical practice.  相似文献   
8.
Henna Ruuska 《Carbon》2003,41(4):699-706
Interactions between a water molecule and one- and two-layer graphite were calculated by ab initio Hartree-Fock (HF) method. Eclipsed coronene dimer (C24H12)2 was used as the two-layer graphite model, to study the behavior of a water molecule in the pressure between two graphite layers. Three one-layer models, C16H10, C42H16, and C80H22, were used as reference to investigate the influence of the adsorption site, the orientation of the water molecule, and the size of the model. Only minor differences were found in the three adsorption sites. The HF interaction was weaker with larger models and stronger with larger basis set (6-31G*).  相似文献   
9.
Achieving water‐induced shape‐memory property in poly(D,L ‐lactide) (PDLLA), generated by means of advanced processing methods, opens possibilities to develop novel bioresorbable medical devices with shape‐memory properties activated by the human body without external heat. The main phenomena that affect the molecular movements that enable the water‐induced shape‐memory effect in an oriented PDLLA in an aqueous environment at physiological temperature are related to the water driven disruption of the intermolecular dipole‐dipole and/or hydrogen bonding of the oriented PDLLA chains and the subsequent decrease of the glass transition temperature (Tg) to the range of physiological temperature. The diffused water in the polymer matrix decreased the energy needed to finish the glass transition process explaining the higher shape‐recovery rate of the γ‐irradiated PDLLA with respect to the non‐γ‐irradiated PDLLA in an aqueous environment at physiological temperatures. The water‐induced decrease in the Tg was thermally reversible. The efficacy of the generated shape‐memory was tested with PDLLA shape‐memory nails in a pullout test, in which the pullout force of the PDLLA nails increased 360% during a seven day test period in vitro at 37°C. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4209–4218, 2013  相似文献   
10.
Despite the ongoing health problem of repetitive strain injuries, there are few tools currently available for ergonomic applications evaluating cumulative loading that have well-documented evidence of reliability and validity. The purpose of this study was to determine the inter-rater reliability of a posture matching based analysis tool (3DMatch, University of Waterloo) for predicting cumulative and peak spinal loads. A total of 30 food service workers were each videotaped for a 1-h period while performing typical work activities and a single work task was randomly selected from each for analysis by two raters. Inter-rater reliability was determined using intraclass correlation coefficients (ICC) model 2,1 and standard errors of measurement for cumulative and peak spinal and shoulder loading variables across all subjects. Overall, 85.5% of variables had moderate to excellent inter-rater reliability, with ICCs ranging from 0.30-0.99 for all cumulative and peak loading variables. 3DMatch was found to be a reliable ergonomic tool when more than one rater is involved.  相似文献   
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