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Obstructive sleep apnea (OSA) is a common sleep respiratory disease. Previous studies have found that the wakefulness electroencephalogram (EEG) of OSA patients has changed, such as increased EEG power. However, whether the microstates reflecting the transient state of the brain is abnormal is unclear during obstructive hypopnea (OH). We investigated the microstates of sleep EEG in 100 OSA patients. Then correlation analysis was carried out between microstate parameters and EEG markers of sleep disturbance, such as power spectrum, sample entropy and detrended fluctuation analysis (DFA). OSA_OH patients showed that the microstate C increased presence and the microstate D decreased presence compared to OSA_withoutOH patients and controls. The fifth microstate E appeared during N1-OH, but the probability of other microstates transferring to microstate E was small. According to the correlation analysis, OSA_OH patients in N1-OH showed that the microstate D was positively correlated with delta power, and negatively correlated with beta and alpha power; the transition probability of the microstate B → C and E → C was positively correlated with alpha power. In other sleep stages, the microstate parameters were not correlated with power, sample entropy and FDA. We might interpret that the abnormal transition of brain active areas of OSA patients in N1-OH stage leads to abnormal microstates, which might be related to the change of alpha activity in the cortex.

Photonic crystals (PCs) have attracted intense interest for sensing applications. Photonic crystal hydrogels (PCHs) consist of both periodic PCs and stimuli-responsive hydrogels, which can act as a sensing system for the detection of specific analytes. In PCHs, the hydrogel system undergoes volume phase transitions (VPT, swelling or shrinkage) upon exposure to external stimuli. The VPT of the hydrogel causes the photonic stopband of the PCs within the hydrogel to change, which shifts the Bragg diffraction peak wavelengths. Based on this sensing mechanism, a variety of PCH sensors that can respond to external stimuli, such as humidity, temperature, pH, hazardous chemicals and biological species, have been reported. In this review, we overview the response mechanism, preparation methods, and biosensing applications of three-dimensional (3D) and two-dimensional (2D) PCHs. 3D and 2D PCH biosensors are systematically summarized according to the types of the target analytes. At the end of this review, we also propose the prospects of PCHs in the field of biosensing.

Using the data of the World Input and Output Table (WIOD) from 2000 to 2014, this paper measures the positions of China and the US in the global value chains (GVCs). We develop a new dual structural decomposition method to analyze the drivers behind the GVC position differences between the two countries from the perspective of intermediate consumption. The results show that (1) China is moving away from both end-users and primary factors, while the U.S. is moving towards both ends of the GVCs. The gap between China and the US in GVCs is widening. (2) About 40% of the difference between the GVC positions of China and the US can be attributed to the difference in industrial structures between the two countries, and the remaining 60% is related to the difference in the GVC positions of the same industries between the two countries. (3) China's three major industries are all embedded in a further GVC position from households, governments, and investors (HGIs) than the US, but they are formed for completely different reasons. The domestic direct effect is the main reason for the resource industry, the multiplier effect is the main driver for the manufacturing industry, and the domestic linkage effect is the main factor for the service industry. (4) The different roles of the two countries in the international division of labor result in the difference in the two countries' consumption coefficients of the manufacturing and service sectors, and the asymmetric interaction between industries ultimately leads to the differentiation in the GVC positions of the industries between the two countries.

The results of experimental investigations on catalytic oxidation of coal mine ventilation air methane in a preheat catalytic reaction reactor is presented in this paper. The experimental system was located in the Energy Research Institute of Shandong University of Technology, which has been applied to investigate the effects of startup conditions such as the startup flow coefficient (0.3–0.5) and the startup power (10 kW–20 kW) on the startup process within the preheat catalytic reaction reactor. The average temperature distribution of catalytic oxidation bed and the minimal startup power were measured and the effects of operating conditions such as the space velocity (2600 h−1 to 11,500 h−1) and the methane concentration (0.8%–1.2%) were experimentally investigated. Moreover, the methane conversion rate and the average temperature of the catalytic oxidation bed were discussed and the critical space velocity value and the critical methane concentration value were determined.

The connecting rod (CR) is the main moving parts and an important component of engine. If the reliability is not strong enough, fatigue failure of the CR would occur, thereby leading to component fracture and engine failure. So much so that CR fracture. It will lead to engine fault as well as serious outcome. In this paper, stress distribution and fatigue life of CR in light vehicle engine were analyzed using the commercial 3D finite element software, ANSYSTM. The results showed that the medial surface of small end will be the critical surface whereby damage will initiate at the maximum stretch condition. The maximum stress and deformation values are 190.23 MPa and 0.0507mm respectively. The critical location is at the transition region between the big end and connecting shank at maximum compression condition. The maximum stress and deformation values are 459.21 MPa and 0.0702283 mm respectively. Safety factor is 1.584. In order to increase the reliability of CR, some improvement is carried out. Safety factor of CR increases by 59%.

To examine the association of the DNA methylation of DAT1 and DRD4 gene with methylphenidate (MPH) response in attention deficit hyperactivity disorder (ADHD).One hundred and eleven DSM-IV defined ADHD Chinese Han children were recruited. Inattention, hyperactivity-impulsivity and oppositional symptoms were evaluated by the Swanson, Nolan and Pelham-IV-parent rating scale (SNAP-IV-P) at baseline and 6 weeks after MPH treatment. DNA methylation of CpG sites in the promoter sequences of DAT1 and DRD4 was examined for association with treatment response.Greater improvement on the SNAP-IV-P total score and percentage change from baseline score were both significantly correlated with DAT1 methylation (rho =-0.222, P = .019 and rho = -0.203, P = .032, respectively). A secondary analysis demonstrated that the effect of DAT1 methylation on symptom response was primarily related to the percentage change in oppositional symptoms (rho = -0.242; P = .012), with a smaller significant effect on hyperactivity-impulsivity (rho = -0.192; P = .045). No significant correlation was found between the treatment effect on inattention and DAT1 methylation (rho = -0.101; P = .292). No significant correlation was observed between mean DRD4 methylation and measures of treatment outcome or baseline symptoms.Our findings provide initial evidence for the involvement of the epigenetic alterations of DAT1 in modulating the response to MPH treatment in ADHD, primarily on oppositional and hyperactive-impulsive symptoms.

The stress analysis and modal analysis of a 4-cylinder crankshaft are discussed using finite element method in this paper. Three-dimension models of 480 diesel engine crankshaft and crankthrow were created using Pro/ENGINEER software The finite element analysis (FEM) software ANSYS was used to analyse the vibration modal and the distortion and stress status of the crankthrow.The maximum deformation, maximum stress point and dangerous areas are found by the stress analysis of crankthrow. The relationship between the frequency and the vibration modal is explained by the modal analysis of crankshaft. The results would provide a valuable theoretical foundation for the optimization and improvement of engine design. Index Terms—finete element analysis; modal analysis; strss analysis; crankshaft

The driving forces of China's Economic Growth are investigated in this paper based on the 1997、 2002 and 2007 input-output data and the following conclusions are gotten: (1) The sources of China’s economics growth during 1997-2007 was mainly from the pull effect of final demands.(2) The deriving forces are different among sectors. The sources of China’s agriculture and tertiary industry during 1997-2007 was domestic consumption demand while the secondary industry dependent on investment and export demand.(3) The engines of China’s economics had changed during the decade. On the first half of the stage, the domestic consumption play dominant role while the contribution of export had increased on the later half of the stage.

The chest bitmap is the most widely used in live-firing. The target surface information extraction is the chief question need to be solved for automatic target-scoring system. Therefore, this paper proposes a new low-complexity algorithm for target surface feature information extraction according to the characteristics of the chest ring image. Based on the pre-processing for image, background interference of the image is eliminated by using regional feature elimination algorithm. Besides, target’s eye position is determined by employing gray two-way clipping projection, and all of the effective feature information of the target surface is extracted. The result of simulation shows that the target surface information extraction algorithm for chest bitmap is characterized by low-complexity, short time-consuming and high efficiency, and meets the real-time requirement.

Inspired by detailed designs of industrial porous burners, the combustion of methane%air mixtures in a non-catalytic reverse-flow reactor was studied numerically. The governing equations are the unsteady state equations of conservation of mass and chemical species, with separate energy equations for the solid and gas phases. These equations were solved using the commercial CFD code Fluent. In order to reveal the actual thermal oxidation in porous media, the user defined function (UDF) is used to extend the ability of FLUENT. The model has been used to investigate the effects of operating conditions such as the mixture inlet approach velocity (0.15 to 0.8 m/s) and methane concentration (0.3 to 0.7%) on the oxidation of methane within non-catalytic reactors packed with ceramic monolith blocks under adiabatic conditions. The calculated values of methane conversion showed good agreement with the corresponding available experimental data. Moreover temperature distribution characteristics in the oxidation bed were studied in order to maintain the autothermicity of TFRR with a high enough temperature in the hot zone. Metan iz premogovnikov ni le toplogredni plin, neizkoriščen je tudi izgubljen vir energije. Zaradi zelo nizkih koncentracij CH4 se kot najobetavnejša rešitev kaže avtotermično zgorevanje v reaktorjih z izmenjevanjem smeri toka. Večina dosedanjih študij je bila posvečena katalitičnemu zgorevanju v katalitičnih reaktorjih z izmenjavanjem smeri toka (CFRR). Ekonomsko in tehnično najprimernejša rešitev za izkoriščanje toplotne energije pa so termični reaktorji z izmenjevanjem smeri toka (TFRR). Nekatalitična oksidacija v TFRR je zato pogosto privlačna alternativa. Tovrstni reaktorji so že dolgo v uporabi, npr. za homogeno kurjenje hlapnih organskih spojin (VOC). Med zgorevanjem VOC in oksidacijo metana iz prezračevalnih sistemov v reaktorjih z izmenjevanjem smeri toka obstajajo očitne razlike. Termično zgorevanje v TFRR mora potekati pri pogojih, ki ne sprožajo čezmernega nastajanja NOx, t.j. maksimalna temperatura v reaktorju je lahko največ 1300 °C. Uporaba TFRR za kurjenje revnih zmesi metana zato zahteva podrobno preučitev delovnih pogojev.

Cultivating innovative talents is an important task of colleges and universities. It is the trend of higher education development and the need of social development. Experiment teaching is an important link to develop students’ practice ability as well as innovative ability and the opening modular experiment teaching is an effective way to train innovative talents. The content, conduct, effect and significance of opening modular experiment teaching were studied in detail basicd on modular experiment course of pyrology.

In this paper, with the ANSYS, stress distribution and safety factor of connecting rod were analyzed by using 3D finite element method. The results show that the inner surface of the transition location of big end and connecting rod shank is the exposed destructive position at maximum stretch condition. Maximum stress value is 118 MPa. Safety factor is 2.99. The exterior surface of the transition location of small end and connecting rod shank is the exposed destructive position at maximum compression condition. Maximum stress value is 127 MPa. Safety factor is 2.77.

Finite element analysis has been used to investigate the vibration modal of 480 crankshaft and the stress analysis of crankpin. The aim of the modal analysis was to explain the relationship between the frequency and the vibration modal. And the aim of the stress analysis of crankpin was to find the maximum deformation and maximum stress point. In this paper, three-dimension models of 480 diesel engine crankshaft and crankpin were created through Pro/ENGINEER software. The finite element analysis (FEM) software ANSYS was used to analysis the vibration modal and the distortion and stress status of the crankpin. The results of crankshaft vibration modal were calculated. And the stress figures of 480 diesel engine crankpin were calculated, combined with maximum stress point and the dangerous area. The results would provide valuable theoretical foundation for the optimization and improvement of engine design.

Crankshaft is one of the most important parts in internal combustion engine. In this paper, a three-dimension model of 380 diesel engine crankshaft was created through Pro/ENGINEER software. The finite element analysis (FEM) software ANSYS was used to analyze the distortion and stress status of the crankshaft. First of all, the 380 diesel engine entity crankshaft model was created by Pro/ENGINEER software. Next, the model of crankshaft created by Pro/E software was imported to ANSYS software. Then, material properties, constraints boundary conditions and mechanical boundary conditions of the 380 diesel engine crankshaft were determined. Finally, the strain and stress figures of 380 diesel engine crankshaft were calculated, combined with maximum stress point and the dangerous area. Then this article checked the crankshaft's static strength and the fatigue evaluations which provide valuable theoretical foundation for the optimization and improvement of engine design.

Face recognition is one of the most challenging research topics in the field of pattern recognition and computer vision. To efficiently deal with this problem, a novel face recognition algorithm is proposed by the combination of local fisher discriminant analysis (LFDA) and least square version of SVM(LS-SVM). Experimental results on real face databases have demonstrated the better performance of the proposed algorithm.

Combustion of coal mine ventilation air methane (VAM) was investigated in a thermal reverse-flow reactor. Effects of CH 4 concentration, VAM flow and temperature were studied. The results show that combustion of coal mine ventilation air methane be achieved for methane concentration of 0.2%~0.8% in reactor. The conversion rates of CH 4 are all above 99%.Some heat could be recovered. With the increase of CH 4 concentration and VAM flow, the temperature of middle area increase, the volume of high temperature increase. It is to improve conversion rate of CH 4 . The lowest combustion temperature is 880degC.

The aperture rebuilding technique in time domain antenna near field measurement is presented in this paper. Without detailed principle introduction, this paper focuses on the realization of practical measurement. The measuring results of standard antenna show perfect character of this technique.

In the practice of antenna time domain planar near field measurement, the pulse generator's time base joggling can cause very big errors in measuring results. In this paper, a time base correction technique is developed to deal with this problem. Besides measuring channel, this technique adds a reference channel in measuring system, and uses the reference channel's time base joggling to correct the measuring channel's signal. The practical measuring results have proved this method's reliability.

Cultivating innovative talents is an important task of colleges and universities. It is the trend of higher education development and the need of social development. Experiment teaching is an important link to develop students’ practice ability as well as innovative ability and the opening modular experiment teaching is an effective way to train innovative talents. The content, conduct, effect and significance of opening modular experiment teaching were studied in detail basicd on modular experiment course of engine.

A new approach to the numbering of detected interference fringes has been developed to enable computer analysis of interferograms containing closed-loop fringes, as captured by a TV-based lens testing Twyman-Green interferometer.3 The method requires some degree of operator intervention to set initial and maximum fringe numbers and information regarding the closed-loop fringes but otherwise is automatic. Following the fringe detection and numbering procedures the controlling computer evaluates "best-fit" values of the coefficients to predetermined aberration polynomials as used to represent the lens wavefront aberration presented in the interferogram. The wavefront aberration has been modelled by two different aberration polynomials, namely the Seidel and Zernike aberration polynomials. The latter polynomial includes additional terms to those in the former, enabling it to fit a wider range of asymmetries in the measured interferogram. It is therefore of considerable interest to compare the 'quality' of the fits obtained using the two aberration polynomials for a variety of interferograms. Results of the total process of data collection, polynomial fitting and lens Optical Transfer function evaluation are presented. The paper compares the residuals of fit, OTF curves and reconstructed interferograms derived from the same interferogram using the two polynomials. These suggest that, in general, the Zernike polynomials are more efficient than the Seidel polynomial.