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Summary: In wireless charging systems for electric vehicles, fluctuations in coil mutual inductance can affect both system output power and efficiency. This paper introduces a coil mutual inductance model that accounts for metal shielding material. The formula for coil mutual inductance is derived using Maxwell's equations and boundary conditions. Additionally, the paper presents a tactic for adapting the mutual inductance with the aid of an intelligent optimization algorithm, which is utilized for steadying the mutual inductance of the transmission coil. Lastly, a model of the transmission coil is developed to authenticate the practicality of the mutual inductance equation and the adaptation scheme. Measurement and calculation results indicate that the difference between the calculated value of the mutual inductance formula and the actual mutual inductance value of the coil, following deflection and offset, is below 5%. Moreover, the algorithm, along with the employed adaptation strategy, consistently demonstrates effectiveness in maintaining the mutual inductance value within a predefined range. The temporal efficiency of the algorithm, as measured by the time taken to determine this coordinate position, is consistently under 1 s. This ensures that the algorithm exhibits a rapid response time, a crucial attribute in ensuring its practical utility. [ABSTRACT FROM AUTHOR]

The complete mitogenome sequence of Blarinella griselda was determined using long PCR. The genome was 16,947 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, 1 origin of L strand replication and 1 control region. The overall base composition of the heavy strand is A (33.1%), C (22.6%), T (31.6%) and G (12.7%). The base compositions present clearly the A–T skew, which is most obviously in the control region and protein-coding genes. Mitochondrial genome analyses based on MP, ML, NJ and Bayesian analyses yielded identical phylogenetic trees. This study verifies the evolutionary status of Blarinella griselda in Soricidae at the molecular level. The mitochondrial genome would be a significant supplement for the Blarinella griselda genetic background. The three Blarinella species formed a monophyletic group with the high bootstrap value (100%) in all examinations.

For problems that existing condition monitoring device for three machines on mechanized mining face is bulky, difficult to install, inconvenience to maintain, and cannot online upgrade program, an intrinsic safety condition monitoring sub-station for three machines based on C8051F040 MCU was developed, and IAP technology was used to achieve online automatic upgrade of condition monitoring device for three machines. The volume of the improved sub-station is only 1/10 of original sub-station, and the improved sub-station can be connected with the existing master station and achieves online monitoring and fault diagnosis of three machines on mechanized mining face. The prototype test results show that the improved condition monitoring device for three machines on mechanized mining face runs reliably, monitors condition accurately and has ability to update programs online.

The paper analyzed dead-time effect and working principle of diode-clamped three-level inverter, proposed a dead-time compensation method which is suitable for diode-clamped three-level inverter based on double carrier modulation. By adjusting dead-time of trigger pulse on different current flow paths, the method realizes level conversion unaffected by dead-time, which means avoiding or reducing dead-time effect. The simulation result shows that the method reduces the 5th and 7th harmonic contents and total harmonic distortion, increases effective current value and has better compensation effect compared with normal dead-time compensation method.

In order to reduce impact of grid voltage asymmetry or distortion on UPF harmonic detection algorithm, an improved UPF harmonic detection algorithm introducing PLL circuit was used to produce fundamental positive sequence voltage and correct active power, which inhibited impact of voltage distortion, while improved real-time performance of detection. Current waveforms of the power supply side before and after the compensation were compared by Matlab, which verifies feasibility of the improved algorithm. Experimental results show that harmonic content of the fifth harmonic which has the highest harmonic content is reduced from 22.8% before the compensation to 8.1% after the compensation by the improved algorithm, and the main harmonic component of the load current has been effectively inhibited, which achieves purpose of harmonic suppression.

In view of problem of poor anti-interference of existing electro-hydraulic control systems, the paper proposed a design scheme of emergency stop function of electro-hydraulic control system of hydraulic supports based on C8051F020 single-chip microcomputer according to characteristics of fully mechanized working face in coal mine underground, and introduced realization process of emergency stop function. In the scheme, all of hydraulic supports of coal mining face can be stopped immediately with an emergency operation on a stop button and they will not respond any operation instructions when taking place emergency, and the coal mining face can regain normal work with an operation on a stop button after the dangerous situation is ruled out. The function test results showed feasibility of the scheme.

For problems that there are no efficient monitoring platform and reliable communication way about on-line monitoring system of mine-used high voltage cable, the paper proposed a design scheme of CAN bus controller of on-line monitoring system of mine-used high-voltage cable, and introduced design of hardware circuit, setting of Baud rate and realization of programming state-machine and SPI communication of the CAN bus controller in details. In the CAN bus controller, FPGA chip EP2C20F484C8 is monitoring core, MCP2510 is bus controller, and Verilog HDL is programming language. The experimental result verified performances of real-time and reliability of the CAN bus controller.

In order to solve problems of consuming too much time and resource and unstable precision caused by environment of existing off-line detecting method for dielectric loss of high-voltage cable of coal mine underground,a micro-current sensor was designed for measuring micro grounding current of cable's earth line,and by use of the sensor,an on-line detecting system for dielectric loss of mine-used high-voltage cable was designed based on zero-crossing point comparing method.The composition and on-line detecting principle of the system were introduced.The results of simulation and test showed that the system has stable performance,high measuring precision and strong anti-interference ability,and can on-line measure dielectric loss of high-voltage cable accurately.

In order to solve the problems of high cost,un-convenient installation and low-precise detection caused by using IR temperature sensor and fiber sensor to detect temperature of isolators in high-voltage distribution equipment at present,an on-line monitoring device of temperature for isolators in high-voltage distribution equipment based on nRF905 was designed,and design of hardware and software of the device was introduced in details.The experimental results showed that circuits of data collection,data receiving and sending and data processing of the device are reasonable,and the device can realize on-line monitoring of temperature of isolators in high-voltage distribution equipment,which has error below(± 1.5 ℃) and meets actual needs of engineering.

In view of problems that software upgrade of support controller and terminal controller of existed hydraulic supports needs underground technical personnel to disassemble each controller, which is time-consuming and low in efficiency, the paper proposed a design of online upgrade scheme of software of electro-hydraulic control system of hydraulic supports. It introduced system composition, changes in the code storage space and program flow for online upgrade in details, and gave experimental data and analysis. The scheme achieves remote online upgrade of support controller and terminal controller, and the upgrade process is easy and fast.

Main observation and conclusion: Single nanoparticle collision has attracted great attention in the last several years to reveal the electron transfer and motion trajectories of individual particles at the electrode surface. An envelope algorithm is proposed for further reading and demonstrating the corresponding current signals, which integrates baseline correction, peak identification and Savitzky‐Golay filter. It is employed for data analysis of the single AgNPs collision on a wireless nanopore electrode to eliminate the current noise and accurately calculate the integrated charges in each current spike. The practicability and robustness of the algorithm are verified under additive Gaussian white noise with the signal‐to‐noise ratio higher than 5. By comparing with traditional Gaussian peak model, the algorithm here shows comparable performance for the peak identification and integrated charge calculation. These results signify a big step from manual Gaussian fitting to automatically data processing method, which facilitates a fast acquisition of intrinsic features in single entity electrochemistry. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Single nanoparticle collision has attracted great attention in the last several years to reveal the electron transfer and motion trajectories of individual particles at the electrode surface. An envelope algorithm is proposed for further reading and demonstrating the corresponding current signals, which integrates baseline correction, peak identification and Savitzky‐Golay filter. It is employed for data analysis of the single AgNPs collision on a wireless nanopore electrode to eliminate the current noise and accurately calculate the integrated charges in each current spike. The practicability and robustness of the algorithm are verified under additive Gaussian white noise with the signal‐to‐noise ratio higher than 5. By comparing with traditional Gaussian peak model, the algorithm here shows comparable performance for the peak identification and integrated charge calculation. These results signify a big step from manual Gaussian fitting to automatically data processing method, which facilitates a fast acquisition of intrinsic features in single entity electrochemistry. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate the association of polymorphisms of STAT6 gene and air pollutants of PM10, NO2, and SO2, with asthma in Chinese children. Methods: 418 subjects aged 14 years and under were recruited in a case-control study. The association between STAT6 polymorphisms and childhood asthma were tested by allele frequency, genotype analysis, and MDR analysis. Exposure to outdoor air pollutants was estimated by a 5-day moving average level. Statistical analyses were performed with SAS 9.1 software. Results: Only 3 alleles of GT repeats at exon 1 of STAT6 were found in Chinese children. C258T and T710C were 2 new SNPs of STAT6 at 3′-UTR. Children who carried T allele of C258T were more common in asthma children than in control subjects (P<0.05). The MDR analysis showed that GT repeats, C258T and T710C of STAT6 polymorphisms interacted together in leading to susceptibility to childhood asthma among Chinese people. After confounding factors were controlled, such as SNP C258T, family history of asthma, frequency of influenza within a year, the 5-day average of SO2 was tested to be a key risk factor of asthma in Chinese children (P<0.05). Conclusion: Chinese children differed in polymorphisms of STAT6 and in its relation with childhood asthma. [Copyright &y& Elsevier]

Objective: To explore the prevalence, diagnosis and management of childhood asthma in Beijing urban area., Methods: Multi-stage, stratified and random cluster sampling was used to recruit children born during November 1, 1995 to October 31, 2010 from Beijing or other provinces but residing in Beijing for over half a year. The same screening questionnaires for the third national epidemiological survey of children's asthma were distributed to parents of children at schools, kindergartens and communities during October 2010 to March 2011. Asthmatic children were picked among the screening-positive children based on on-the-spot inquiries, physical examinations, medical records and supporting test results. Further survey of asthmatics was carried out to investigate the diagnosis and treatment status of childhood asthma and other associated allergic diseases. All data required double entry by Epi-Info 3.5.3 software and were processed by SPSS 19.0., Results: Among a total of 14 085 questionnaires, 13 513 were completed with a response rate of 95.94%. And 497 (3.68%) children were diagnosed with typical (n = 451, 3.34%) and cough variant (n = 46, 0.34%) asthma. Among them, 40.64% (202/497) were newly diagnosed and 59.36% (295/497) had been previously diagnosed with asthma. The prevalence of asthma was higher in boys than in girls (4.80% (345/1790) vs 2.40% (152/6323), χ(2) = 54.446, P < 0.01). The asthma prevalence of preschoolers (3 - < 7 years old) was the highest (5.05% (180/3563)). In the past two years, the symptoms of 69.42% (345/497) children persisted and the current two-year prevalence of asthma was 2.55% (345/13513). Among the 295 children with previous asthma, only 46.44% (137/295) received inhaled corticosteroids according to the Global Initiative for Asthma (GINA) and 82.37% (243/295) of them used antibiotics., Conclusions: The prevalence of asthma is 3.68% in children under 14 years old in Beijing urban area and it varies in children with different genders and ages. A considerable number of children are not diagnosed or treated properly. And the management of asthma requires further improvement.