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Rock burst is one of the main coal and rock dynamic disasters in steeply inclined and extremely thick coal seams (SIETCS). Timely identification of potential precursor information enables effective and specifically targeted measures to mitigate hazards. To provide a reference for the determination of precursor information in SIETCS with similar conditions, an in situ investigation that lasted for more than 1 year was conducted on the + 450 horizontal no. B3 + 6 fully mechanized top-coal caving face of the Wudong coal mine. This mine has an average dip angle of 87° and experienced a total of three rock bursts. The investigation focused on the consequences of rock burst (including the source location, energy, damage range, and modes of ensuing damage), the temporal and spatial evolution laws of the monitoring parameters of microseismic (MS) and acoustic emissions (AE), and the relationship between precursory information of both the AE and MS monitoring systems. Furthermore, a comparison of the evolution laws of the precursory characteristics between steeply and gently inclined coal seams was conducted. The obtained results indicate that rock burst failure mainly shows a directionality from south to north of the roadway, and the main factor causing the rock burst was the suspended rock pillar. Prior to the rock burst, sources of MS events gradually clustered and congregated around the rock pillar or coalface, and high-energy events (energy > 103 J) noticeably increased. Similar variations of sharp rise–sharp drop were found for both daily total energy and event counts. Prior to rock burst or large energy mine tremors, the AE energy deviation continued to rise, a peak was observed in the total number of high-value daily AE deviations, and the precursory information of AE was ahead of the precursory information of the MS monitoring system. The evolution laws of MS precursor information prior to rock burst differed between SIETCS and gently inclined coal seams. These evolution laws can be used as precursory warning for rock burst in SIETCS. Integrated monitoring of the AE and MS monitoring systems realizes the real-time monitoring and early warning from the germination stage to the occurrence of rock burst, and can determine the danger area in space. This can improve the early warning efficiency and provides a solid foundation for safe mining in SIETCS.

BACKGROUND: Germline ATM mutations are suggested to contribute to predisposition to prostate cancer (PrCa). Previous studies have had inadequate power to estimate variant effect sizes. OBJECTIVE: To precisely estimate the contribution of germline ATM mutations to PrCa risk. DESIGN, SETTING, AND PARTICIPANTS: We analysed next-generation sequencing data from 13 PRACTICAL study groups comprising 5560 cases and 3353 controls of European ancestry. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Variant Call Format files were harmonised, annotated for rare ATM variants, and classified as tier 1 (likely pathogenic) or tier 2 (potentially deleterious). Associations with overall PrCa risk and clinical subtypes were estimated. RESULTS AND LIMITATIONS: PrCa risk was higher in carriers of a tier 1 germline ATM variant, with an overall odds ratio (OR) of 4.4 (95% confidence interval [CI]: 2.0-9.5). There was also evidence that PrCa cases with younger age at diagnosis (

Aiming at problem of low efficacy of early warning of rock burst in coal mine, a multisystem and multiparameter integrated early warning method based on genetic algorithm (GA) is proposed. In this method, firstly, the temporal-spatial-intensity information of energy incubation process of rock burst is deeply mined, and the multidimensional precursory characteristic parameter system of rock burst is constructed. Secondly, the genetic algorithm is used to train the historical monitoring data to obtain the optimal critical value and fitness value of each precursory characteristic parameter, and then the early warning index WC of each monitoring system is calculated. Finally, the integrated rock burst early warning index IC is obtained by synthesizing the early warning index WC of each system. The value of IC corresponds to the specific rock burst risk level of the mine. This method is applied to Wudong coal mine in Xinjiang, China. Based on the actual situation of the mine, a multidimensional precursory characteristic parameter system of rock burst is constructed, which includes energy deviation (DE), frequency ratio (Fr), frequency deviation (DF), degree of dispersion (DS), and total high value of energy deviation (DH). After analyzing the rock burst danger status and risk level in the monitoring area, the early warning capability of this method is found to reach 0.896. Combining with the specific prevention and control measures corresponding to different rock burst risk levels, it can provide effective guidance for the field work.

This paper designs a new AC & DC hybrid power supply system for data centres, which includes photostatic power generation, wind power generation, solar thermal power generation, storage power systems, and different types of loads. According to the above-mentioned, the paper first presents the reliability evaluation indicators and analysis methods applicable to the new AC & DC hybrid power supply system for data centres, which are for solving the problem of the reliability evaluation under uncertain parameters and load parameters of the new data centre power supply system. The paper describes the new power supply system reliability indicators and evaluation methods in detail. The problem of the power supply reliability in the new AC & DC hybrid power supply system in the data centre is analysed in a targeted manner by adopting actual examples, then it is verified that the power supply reliability of the new AC & DC hybrid power supply system can perfectly meet the qualification of the A-class data centre power supply. The reliability of assessment index and analysis methods presented here will be two simple and superior analysing tools.

Thermoacoustic technology is becoming increasingly attractive because of its high reliability and environmental friendliness. The double-acting traveling-wave thermoacoustic heat engine using liquid pistons, proposed by our group, can improve the thermoacoustic conversion efficiency further and yield a more compact engine. In this study, three different environmentally friendly working gases, helium, nitrogen and carbon dioxide, were studied experimentally, primarily in terms of thermoacoustic conversion parameters, including the onset temperature, the resonant frequency, and the pressure ratio, under different working mean pressures. Results show that the working gas significantly influences thermoacoustic performance. They also suggest a very encouraging application prospect for this novel thermoacoustic heat engine. Finally, we performed theoretical analysis to better understand thermoacoustic conversion with the different working gases.

This paper presents a novel experimental system of conversion between heat and power of the kW-class thermoacoustic engine, at both ends of the thermoacoustic core components the compression and expansion motors are added. By adjusting the parameters of motors like spring stiffness, moving mass, inductors and external resistors in order to easily and comprehensively adjust the pressure fluctuations, volume flow rate, acoustic field and phase angle in engine, we can better research on the performance of conversion between heat and power of thermoacoustic engine and impedance matching on motors and engine. It has important significance of improving working performance of thermoacoustic engine and optimal selection of parameters of compression and expansion motors. By optimizing the parameters of the compression and expansion motors, we get the maximum net acoustic power up to 1 kW or more and the highest thermoacoustic efficiency of about 36%. When the phase differences between two ends of volume flow rate reach −120°, it can better fit the acoustic field of double-acting thermoacoustic engine in the loop with a good guiding value. In the future experimental studies, we can improve the net acoustic power and efficiency in order to adapt to different applications and research needs.

The security problems of wireless sensor networks (WSNs) have already arisen and taken an important role in recent years among the international research community. Among all the safety threatens, a series of harmful attacks against WSNs is known as internal attacks, where the adversary captures sensor node and turns it into malicious node. Furthermore, it is still not easy to detect all these attacks, especially when internal attacks try to combine with each other. This paper presents a reputation-based method aimed to defend against the combination of internal attacks, like on-off attack, camouflage attack and constant attack. In the end, simulation shows that the practicability of the method and proves that the method enhances the reliability and security of networks.

The Gene Ontology (GO) project (http://www.geneontology.org/) provides a set of structured, controlled vocabularies for community use in annotating genes, gene products and sequences (also see http://www.sequenceontology.org/). The ontologies have been extended and refined for several biological areas, and improvements to the structure of the ontologies have been implemented. To improve the quantity and quality of gene product annotations available from its public repository, the GO Consortium has launched a focused effort to provide comprehensive and detailed annotation of orthologous genes across a number of ‘reference’ genomes, including human and several key model organisms. Software developments include two releases of the ontology-editing tool OBO-Edit, and improvements to the AmiGO browser interface.

For the structural characteristics of the inverter main circuits usually used in PV grid-connected systems, a novel PV grid-connected power conditioning system(PVPCS) is proposed, in which reactive power compensation and harmonic suppression are integrated. The system can improves not only power quality but also efficiency, and reduces power wasting. The working principle of the system, instantaneous reactive theory, the combination of grid-connected current and grid-connected current tracking are discussed. PVPCS based on fuzzy sliding variable-structure control (FSMC) is also discussed. The transient simulation of one machine infinite bus system is executed, and the results are compared with traditional PI control. The results of simulation prove the feasibility of the system configuration and control strategy presented above.

To understand and master the alien biological disaster knowledge is the basis for right control of alien biology. Ontology is the tool for knowledge sharing and integration. Aiming at alien biological disaster knowledge, the construction thought of alien biological disaster knowledge ontology is analyzed in this paper, and a kind of highly structured organization of domain ontology construction method of MSOBCO and MSOBCO development method has been put forward and alien biological disaster knowledge ontology integration has been analyzed.

Rice pests and diseases' occurrence and development are closely linked with climate change. Its' occurrence and outbreak have a certain similarity on weather conditions. In order to improve the prevention and control level of pests and diseases of rice, this paper establishes rice pests and diseases warning case based reasoning using data mining technology and implemented forecast adopting database case retrieval methods based on similarity measurement principle.

In this paper, to settle the problem of group decision making in terms of partial information formed in a kind of linguistic verdict matrix, a group decision making approach is put forward based on rough sets using the dominance-based rough sets model. It is in fact a process of decision making after training. It is especially fit for the issue of best-choosing from large scale schemes. Besides, it can overcome the defects of the previous linguistic decision making approaches and can make the best scheme.

SUMMARY This paper proposes a gas–liquid, double-acting traveling-wave thermoacoustic heat engine (GLDA-TWTHE), which has the advantages of both traditional thermoacoustic engine with long life span and the Stirling engine with high power density and high efficiency. By connecting three or four same thermoacoustic engines into a loop with a U-type liquid resonator, each engine can work in an ideal traveling-wave field, consequently bringing about high thermoacoustic conversion efficiency. We designed such an experimental system with about 3 kW acoustical power. The GLDA-TWTHE consists of three same thermoacoustic heat engine units and three same U-type liquid-water columns with about a diameter of 50 mm. The operating heating temperature, ambient temperature, and resonant frequency are 923 K, 303 K, and 25 Hz, respectively. Before the experiment, numerical simulation on the GLDA-TWTHE under no-load and loaded conditions was made for providing a theoretical prediction. Also, we have analyzed the influence of some parameters of the three engines being inconsistent with each other on the system performance. Finally, the experimental results were compared with the simulation, showing good agreement with each other. Based on both the theoretical and experimental results, it is found that the novel GLDA-TWTHE is a very enabling technology due to its high reliability, simple structure, and high efficiency. Copyright © 2013 John Wiley & Sons, Ltd.

A feature extraction method for Epilepsy diagnosis is proposed in this paper, which can be incorporated in automatic/semi-automatic epilepsy diagnosis systems to improve diagnosis efficiency from multi-channel Electroencephalogram signals. This method calculates the Robust Generalized Synchrony between pairs of Electroencephalogram channels in the first step. Then six character parameters are extracted from the Robust Generalized Synchrony values for the whole brain and the sub-brain regions. A set of Electroencephalogram data including 20 normal objects and 20 epileptic patients in interictal states were used to test the proposed method The results demonstrate that these features are effective to differentiate between epilepsy patients and the normal objects with the p-values smaller than 0.01.

Against soft starting of 3-phase induction motors with heavy loads which is achieved by means of Discrete Variable Frequency(DVF) and electricity-economizing control system in light load situation, some technical problems are analyzed and studied. Analysizes the optimal combination of phase sequence of DVF bands based on the theory of DVF soft starting. The given voltage of the initial frequency is appropriately increased, in order to make up the voltage drop resulting from the freewheel problems of equivalent sine policy. Based on the power factor angle the closed-loop control strategy is designed. Based on control strategy of optimal adjustion voltage, Energy saving measures are taken on the condition of light load;The soft ware and hard ware of the control system are designed at last. Simulations results made by MATLAB/simulink under light load configurations are presented to show the reliability and the effectiveness.

In order to improve the conversion efficiency of photovoltaic array, photovoltaic energy system usually requires maximum power point tracking (MPPT) controller. The principle of commonly used MPPT techniques is analyzed, and their advantages and disadvantages are compared. A fuzzy controlling scheme is designed for the photovoltaic MPPT based on the characteristic of the photovoltaic array and the Duty Cycle Perturb method. The detail about designing a fuzzy control is proposed and a simulation is carried out with MATLAB to test the effect of the controller. Simulation results show that the maximum power point can be tracked well. The fuzzy logic control provides faster tracking, solves the considerable oscillation near the maximum power point and reduces severe power loss.

This paper focuses on the decoupled control of active and reactive power for variable speed constant frequency (VSCF) wind generation system. The principle of maximum wind power tracking for wind generation system is analyzed. Based on the mathematic model of doubly fed induction generator (DFIG) in two-phase synchronous coordinate system, the decoupled control of active and reactive power indirectly realizing maximum wind power tracking is further studied, using the method of stator field oriented vector control. An effective method of independent active power and reactive power control is proposed. Detailed simulation on MATLAB/SIMULINK verifies the feasibility and validity of the proposed control strategy.

This article introduces wavelet analysis theory to identify inrush and internal fault correctly. The wavelet transform has the characteristic of multi-scale analysis and good time and frequency domain localization, fits to extract sudden-change signals in transient processes, and detects irregularity of signals very well. This article analyzes the mechanism of transformer generating excitation inrush, and establishes simulation models of transformer inrush and internal fault. According to different characteristic between inrush and internal fault, choose a proper kind of wavelet to analyze waveforms of inrush and fault current, and mass simulation results show the method can distinguish inrush and internal fault rapidly and accurately.

The ground-based polarization remote sensing adds the polarization dimension information to traditional intensity detection, which provides a new method to detect atmospheric aerosols properties. In this paper, the polarization measurements achieved by a new multi-wavelength sun photometer, CE318-DP, are used for the ground-based remote sensing of atmospheric aerosols. In addition, a polarized vector radiative transfer model is introduced to simulate the DOLP (Degree Of Linear Polarization) under different sky conditions. At last, the correlative analysis between mass density of PM2.5 and multi-wavelength and multi-angular DOLP is carried out. The result shows that DOLP has a high correlation with mass density of PM2.5, R2>0.85. As a consequence, this work provides a new method to estimate the mass density of PM2.5 by using the comprehensive network of ground-based sun photometer.

Altres ajuts: The authors acknowledge the contribution of the staff of the Cancer Genomics Research Laboratory (CGR) at the National Cancer Institute, NIH, for their help throughout the project. This work was supported by the Intramural Research Program of the US National Institutes of Health (NIH), National Cancer Institute. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government. Additional acknowledgements for individual participating studies are listed in the Supplemental Materials. Genome-wide association studies (GWAS) have identified common pancreatic cancer susceptibility variants at 13 chromosomal loci in individuals of European descent. To identify new susceptibility variants, we performed imputation based on 1000 Genomes (1000G) Project data and association analysis using 5,107 case and 8,845 control subjects from 27 cohort and case-control studies that participated in the PanScan I-III GWAS. This analysis, in combination with a two-staged replication in an additional 6,076 case and 7,555 control subjects from the PANcreatic Disease ReseArch (PANDoRA) and Pancreatic Cancer Case-Control (PanC4) Consortia uncovered 3 new pancreatic cancer risk signals marked by single nucleotide polymorphisms (SNPs) rs2816938 at chromosome 1q32.1 (per allele odds ratio (OR) = 1.20, P = 4.88×10 −15), rs10094872 at 8q24.21 (OR = 1.15, P = 3.22×10 −9) and rs35226131 at 5p15.33 (OR = 0.71, P = 1.70×10 −8). These SNPs represent independent risk variants at previously identified pancreatic cancer risk loci on chr1q32.1 (NR5A2), chr8q24.21 (MYC) and chr5p15.33 (CLPTM1L - TERT) as per analyses conditioned on previously reported susceptibility variants. We assessed expression of candidate genes at the three risk loci in histologically normal (n = 10) and tumor (n = 8) derived pancreatic tissue samples and observed a marked reduction of NR5A2 expression (chr1q32.1) in the tumors (fold change -7.6, P = 5.7×10 −8). This finding was validated in a second set of paired (n = 20) histologically normal and tumor derived pancreatic tissue samples (average fold change for three NR5A2 isoforms -31.3 to -95.7, P = 7.5×10 −4 -2.0×10 −3). Our study has identified new susceptibility variants independently conferring pancreatic cancer risk that merit functional follow-up to identify target genes and explain the underlying biology.

In 2020, 146,063 deaths due to pancreatic cancer are estimated to occur in Europe and the United States combined. To identify common susceptibility alleles, we performed the largest pancreatic cancer GWAS to date, including 9040 patients and 12,496 controls of European ancestry from the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4). Here, we find significant evidence of a novel association at rs78417682 (7p12/TNS3, P = 4.35 × 10−8). Replication of 10 promising signals in up to 2737 patients and 4752 controls from the PANcreatic Disease ReseArch (PANDoRA) consortium yields new genome-wide significant loci: rs13303010 at 1p36.33 (NOC2L, P = 8.36 × 10−14), rs2941471 at 8q21.11 (HNF4G, P = 6.60 × 10−10), rs4795218 at 17q12 (HNF1B, P = 1.32 × 10−8), and rs1517037 at 18q21.32 (GRP, P = 3.28 × 10−8). rs78417682 is not statistically significantly associated with pancreatic cancer in PANDoRA. Expression quantitative trait locus analysis in three independent pancreatic data sets provides molecular support of NOC2L as a pancreatic cancer susceptibility gene., Genetic variants associated with susceptibility to pancreatic cancer have been identified using genome wide association studies (GWAS). Here, the authors combine data from over 9000 patients and perform a meta-analysis to identify five novel loci linked to pancreatic cancer.