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1.
Sarcopenia is a disease that becomes more prevalent as the population ages, since it is directly linked to the process of senility, which courses with muscle atrophy and loss of muscle strength. Over time, sarcopenia is linked to obesity, being known as sarcopenic obesity, and leads to other metabolic changes. At the molecular level, organokines act on different tissues and can improve or harm sarcopenia. It all depends on their production process, which is associated with factors such as physical exercise, the aging process, and metabolic diseases. Because of the seriousness of these repercussions, the aim of this literature review is to conduct a review on the relationship between organokines, sarcopenia, diabetes, and other metabolic repercussions, as well the role of physical exercise. To build this review, PubMed-Medline, Embase, and COCHRANE databases were searched, and only studies written in English were included. It was observed that myokines, adipokines, hepatokines, and osteokines had direct impacts on the pathophysiology of sarcopenia and its metabolic repercussions. Therefore, knowing how organokines act is very important to know their impacts on age, disease prevention, and how they can be related to the prevention of muscle loss.  相似文献   
2.
We introduce a generalized Pólya urn model with the feature that the evolution of the urn is governed by a function which may change depending on the stage of the process, and we obtain a Strong Law of Large Numbers and a Central Limit Theorem for this model, using stochastic recurrence techniques. This model is used to represent the evolution of a family of acyclic directed graphs, called random circuits, which can be seen as logic circuits. The model provides asymptotic results for the number of outputs, that is, terminal nodes, of this family of random circuits.  相似文献   
3.
Four strains representing a novel yeast species belonging to the genus Candida were independently isolated in Taiwan and Ecuador. Two strains (G17(T) and G31) were isolated in Taiwan, by pellet precipitation from plastic-bottled tea drinks produced in Indonesia, while two additional strains (CLQCA 10-049 and CLQCA 10-062) were recovered from ancient chicha fermentation vessels found in tombs in Quito, Ecuador. These four strains were morphologically, and phylogenetically identical to each other. No sexual reproduction was observed on common sporulation media. Large-subunit (LSU) rRNA gene sequence analysis revealed the four strains to belong to the Lodderomyces clade, closely related to members of the Candida parapsilosis species complex. The four strains, which have identical LSU D1/D2 sequences, differ from their closest phylogenetic neighbors, Candida orthopsilosis and Candida parapsilosis, by 6-9 nt substitutions, respectively. Physiologically, the four strains are similar to Candida parapsilosis, although they can be distinguished from their closest relative by the assimilation of arbutin, nitrite, and creatine. The Indonesian and Ecuadorian strain sets can also be distinguished from one another based on ITS sequencing, differing by 4 substitutions in ITS1 and 1 single nucleotide indel in ITS2. Collectively, the results indicate that the four strains represent a previously unrecognized species of Candida. The name Candida theae sp. nov. is proposed to accommodate these strains, with G-17(T) (BCRC 23242(T)=CBS 12239(T)=ATCC MYA-4746(T)) designated as the type strain.  相似文献   
4.
Automated activity recognition enables a wide variety of applications related to child and elderly care, disease diagnosis and treatment, personal health or sports training, for which it is key to seamlessly determine and log the user’s motion. This work focuses on exploring the use of smartphones to perform activity recognition without interfering in the user’s lifestyle. Thus, we study how to build an activity recognition system to be continuously executed in a mobile device in background mode. The system relies on device’s sensing, processing and storing capabilities to estimate significant movements/postures (walking at different paces—slow, normal, rush, running, sitting, standing). In order to evaluate the combinations of sensors, features and algorithms, an activity dataset of 16 individuals has been gathered. The performance of a set of lightweight classifiers (Naïve Bayes, Decision Table and Decision Tree) working on different sensor data has been fully evaluated and optimized in terms of accuracy, computational cost and memory fingerprint. Results have pointed out that a priori information on the relative position of the mobile device with respect to the user’s body enhances the estimation accuracy. Results show that computational low-cost Decision Tables using the best set of features among mean and variance and considering all the sensors (acceleration, gravity, linear acceleration, magnetometer, gyroscope) may be enough to get an activity estimation accuracy of around 88 % (78 % is the accuracy of the Naïve Bayes algorithm with the same characteristics used as a baseline). To demonstrate its applicability, the activity recognition system has been used to enable a mobile application to promote active lifestyles.  相似文献   
5.
Accessibility is essentially a dynamic concept. However, most studies on urban accessibility take a static approach, overlooking the fact that accessibility conditions change dramatically throughout the day. Due to their high spatial and temporal resolution, the new data sources (Big Data) offer new possibilities for the study of accessibility. The aim of this paper is to analyse urban accessibility considering its two components –the performance of the transport network and the attractiveness of the destinations– using a dynamic approach using data from TomTom and Twitter respectively. This allows us to obtain profiles that highlight the daily variations in accessibility in the city of Madrid, and identify the influence of congestion and the changes in location of the population. These profiles reveal significant variations according to transport zones. Each transport zone has its own accessibility profile, and thus its own specific problems, which require solutions that are also specific.  相似文献   
6.
Using PCR‐ligated long flanking homology cassettes, null alleles of six open reading frames (ORFs) from chromosome II have been created in Saccharomyces cerevisiae. Deletants were constructed in three genetic backgrounds: FY1679, W303 and CEN.PK2. Tetrad analysis of heterozygous deletants revealed that none of the ORFs is essential for vegetative growth. Basic phenotypic analysis of haploid deletants showed that deletion of the YBR283c ORF causes a slight growth defect at 30°C and 37°C on glycerol‐complete, glucose‐complete, and glucose‐minimal media only in the FY1679 and W303 backgrounds. Transformation of these deletants with the corresponding cognate gene in a centromeric plasmid complements the defects. Deletion of the YBR287w ORF leads to poor growth on glucose‐minimal medium at 15°C in the FY1679 background. None of the six ORFs seems to be involved in mating or sporulation. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
7.
In this study we are reporting the results of an external evaluation carried out on an experimental on-line course developed as part of the European project Multidimensional Approach for Multiplication of Training Environments (MAMUT) (E/99/1/61440/PI/III.3.a/CONT). The aim was to identify psychopedagogical processes that might influence the dynamics of the on-line course and to detect unexpected results. Qualitative analysis of the content of the three hundred and fifty six (356) messages written by the participants in the virtual environment was undertaken. The aspects analysed were: Adaptation to Virtual Environment, Content, Resources, Timing, Tasks, Students’ characteristics, Students’ interaction, and Students-Facilitator interaction.  相似文献   
8.
Two estimators of the expectation of a function, the classical based in Monte Carlo sampling method and one based in Random Riemann Sums, are compared. It presents the differences on bias, variance, convergence and mainly convergence rates. Two ways of sampling to obtain a Random Riemann Sum estimator are given. The first one provides a sequence of estimations whose terms are independent, this fact produces a loss of order one in the convergence rate for the strong law compared with Monte Carlo sampling method. The second one is considered in order to improve these results.  相似文献   
9.
Agripellets from barley straw wastes have been produced in an annular die pellet mill. The semi-industrial scale of the pilot plant allowed for measurement of the die temperature, and an accurate control of the straw moisture at the die inlet. The pellet mechanical durability, density, length and moisture were evaluated for pure straw and blended pellets, together with the heating value and the ash content. The composition of the raw material barely changed with the compaction process. Optimum moisture contents for dense barley straw pellets production proved to be in the range of 19-23%. A durability value of 95.5% was reached under these conditions, increasing to 97-98% when small quantities of pine sawdust were added (2, 7, and 12 wt.% of pine in straw). Agglomeration of the ground particles was improved by water and pine addition, while a coarser grinding did not show any negative effect on barley straw compaction.  相似文献   
10.
This work is focused on the study of orthogonal cutting of long fiber composites. A model based in finite element was developed. The mechanisms of chip formation of Glass and Carbon Fiber Reinforced Polymer (FRP) composites were analyzed. Significant differences were observed when comparing machining induced damage predicted with the model for both materials. While damage extended widely ahead the interface and beneath the tool tip in the case of GFRP, damage was located in a much smaller zone in the case CFRP. The fiber orientation influences both the mechanism of chip formation and the induced subsurface damage.  相似文献   
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