A six-element endfire array is proposed for coal mine or tunnel communication in this letter. To further decrease the end cross section, which has adverse effect on air ventilation, meander-line ...folded dipoles are used as antenna elements. By the antenna itself, the cross section toward the ventilation direction is only 100 × 1 mm 2 . A prototype array is fabricated and tested. Bidirectional endfire radiation patterns with low cross-polarization levels in the azimuth and elevation plane are achieved. The measured - 10-dB bandwidth is approximately 7.5% (834-899 MHz), and the corresponding peak gain is 8.05-9.05 dBi.
Wireless power transfer (WPT) via coupled magnetic resonance is a promising technology to be applied in many fields. In general, there will be a radial gap in practical application, and some special ...application environments need to limit the radius of the coils. Therefore, in this paper, considering the comprehensive analysis of the radial gap and the radius of the coils, the concept of the ratio of radial gap to the radius of the coils was proposed. Based on the circuit theory, the formula between the ratio and transmission efficiency of WPT was deduced, and the effects of the ratio on the transmission efficiency were studied respectively at different axial distances. Simulation experiments were carried out and the results not only demonstrate the influence law of the ratio on transmission efficiency, but also validate the value of the ratio which the axial distance has the greatest effect on the transmission efficiency. Besides, the results shows the relationship between the effect of the ratio on the efficiency and the effect of the axial distance on the efficiency. The experimental results show that the theoretical analysis is correct, thus providing an useful theoretical reference for the design and further research on the wireless power transfer system in complicated environment.
Barrier coverage is one of the research hot spots of wireless sensor network coverage control. In order to fix the defects and deficiencies of the network, which is composed of all isomorphic nodes ...in the barrier coverage, Voronoi diagram is introduced to divide the entire deployment area. According to the principle of the least square method, a mixed network deployment mechanism consisting of static nodes and dynamic nodes is established with static nodes working as the reference barrier line. By monitoring whether there is a barrier covering the blind spot in the deployed area, the monitoring area can be effectively covered by determining whether dynamic nodes need limited movement to redeploy the monitored area. And puts forward mixed node barrier covered in this algorithm, algorithm Voronoi diagram was used for continuous path problem domain discretization, and from different dimensions to compare coverage performance of each algorithm, the simulation experiments show that the algorithm improves the quality of monitoring area coverage, under the same conditions as other algorithms, a mobile node distance and low energy consumption, less expected to cover requirements and goals are met.
This study aimed to screen and verify the important prognostic genes related to clear cell renal cell carcinoma (ccRCC) and further analyze their relationship with the immune microenvironment. Gene ...expression profiles from the TCGA-KIRC, GSE46699, GSE36895, and GSE16449 datasets were utilized to explore differentially co-expressed genes in ccRCC. We screened 124 differentially co-expressed genes using a weighted gene co-expression network and differential gene expression analyses. Univariate and multivariate Cox survival analyses revealed that the expressions of genes
, and
were independently related to the overall survival of ccRCC patients. Kaplan-Meier survival analysis was performed, and
was found to have the strongest correlation with the prognosis of ccRCC patients and was consequently selected for further analyses and experimental verification. The results showed that NK cell activation, resting dendritic cells, resting monocytes, and resting mast cells were positively correlated with
expression; CD4
memory activated T cells, regulatory T cells, and M0 macrophages were negatively correlated with
expression. Finally, using western blotting and reverse transcription polymerase chain reaction, we verified that the
protein level was down-regulated in ccRCC samples, which was consistent with the mRNA levels.
was thus identified as diagnosis and prognosis biomarker for ccRCC and is related to the immune microenvironment.
Methane sensor based on micro-ring resonator WANG Wenqing; WANG Xiaolu; TIAN Zijian
Gong kuang zi dong hua = Industry and mine automation,
02/2016, Letnik:
42, Številka:
2
Journal Article
Recenzirano
Odprti dostop
A new type of methane sensor was proposed which was based on micro-ring resonator. The sensor is coated cryptophane A on micro-ring surface to increase effective refractive index of the micro-ring, ...so as to make resonance wave length in the micro-ring resonator drift towards the right along with methane concentration increasing. Methane concentration is gotten by measuring the outputted resonance wave length. The theoretical analysis results show that change of the outputted resonance wave length of the sensor is within a free spectral range, and methane concentration measuring range is 0~15%. By comparing measurement results of SOI material and polymer material, single sensitive film and three sensitive films, a conclusion is gotten that polymeric material micro-ring with three sensitive films has larger variation width of resonance wave length, which has measurement sensitivity of 60 pm.
NMR relaxometry has been widely applied to characterize fluid confined in porous media because of its versatility, chemical selectivity, and noninvasive nature. Here we extend its usage to gas ...adsorbed in microporous materials by establishing a new quantitative model based on the molecular level NMR relaxation mechanism revealed by the molecular simulation of a prototypical adsorption system, CH4 adsorbed in ZIF-8. The model enables new NMR relaxometry-based characterization methods for thermodynamic, dynamic, and structural properties of adsorption systems, as demonstrated and validated by the experiments where the adsorption capacity and self-diffusivity of H2, CH4, and small alcohols adsorbed in ZIF-8 are deduced from the NMR relaxation data. The findings can serve for a better understanding of the composition–structure–properties relationships of a wide range of adsorption systems which is essential for the development and application of new functional microporous materials.
For problems of low positioning accuracy of electromagnetic wave ranging positioning method due to underground electromagnetic interference and continuous measurement and storage of massive offline ...data in offline construction of fingerprint feature database by fingerprint positioning method, a region discretization mine target positioning method based on compressed sensing was proposed. Firstly, positioning area is divided into grids for discretization, and fingerprint feature database is constructed by offline measuring signal strength at the grid. Then, sparse position matrix containing target position information is obtained by compressed sensing with a small amount of signal strength sampled online, so as to estimate possible position of the target. Finally, the target is accurately positioned by grid centroid method. The experimental results show that the method achieves accurate positioning of mine target with higher positioning accuracy and less positioning time.
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