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Background Global simultaneous recording of activation during atrial fibrillation (AF) can elucidate underlying mechanisms contributing to AF maintenance. A better understanding of these mechanisms may allow for a personalised ablation strategy to treat persistent AF. Purpose To characterise left atrial endocardial activation patterns during AF using a novel non-contact dipole density mapping. Methods Activation patterns were characterised into three sub-types: (i) focal with centrifugal activation (FCA); (ii) localised rotational activation (LRA); (iii) localised irregular activation (LIA). Continuous activation patterns were quantified and distributed in the left atrium. Results A total of 144 persistent AF segments with 1068 activation patterns from 25 patients were analysed. The most common pattern was LIA (63%), which consist of four disparate features: slow conduction (45%), pivoting (30%), collision (16%) and acceleration (7%). LRA was the second commonest pattern (20%). FCA (17%) arose frequently from the PVs/ostia. Continuous AF activations comprise multiple combinations of FCA, LRA and LIA, transitioning from one to the next without a discernible order. Preferential conduction areas were typically seen in mid-anterior (48%) and lower-posterior (40%) walls where dominant activations were made up of LRA and LIA. Conclusion AF is characterised by heterogenous activation patterns that vary between individuals. Clinical implications of individualised ablation strategies guided by dipole density mapping will have to be determined. Acknowledgement/Funding None

To overcome the hysteresis of a tip/tilt mirror(TTM)in an adaptive optical system and to improve its linearity and control precision,this paper researches the nonlinear effects of the TTM.A compensation method based on the frequency-dependent Mutified-Prandtl-Ishlinskii(MPI)model is proposed for online adaptive inverse compensation of the hysteresis nonlinearity of the TTM.By combining with PID feedback control algorithm,an adaptive inverse feedforward composite control algorithm is proposed.In which,the adaptive inverse feedforward overcomes the hysteresis curve changes due to the frequency factors,and the PID algorithm improves the overall control performance.A second-order model of the TTM is established to estimate the output of the TTM system,which solves the reference signals of the MPI model,avoids adding extra feedforward sensors,and ensures the utilization of light energies.Experiment results indicate that this algorithm effectively solves the problemof hysteresis nonlinearity of the TTM,the 15 Hz hysteresis ratio of the TTM fells from 24.28% to1.17%,and the linearity is improved by about 95%.As compared with the traditional PID algorithm,the control precision has increased by about 60%.It concludes that this composite control algorithm can compensate the hysteresis nonlinearity of the TTM effectively,and the control precision of the TTM is improved in adaptive optical systems.

OBJECTIVE To evaluate the prevalence of Helicobacter pylori (H. pylori, HP) infection in subjects receiving routine physical examination and its associations with age, sex, body mass index (BMI) and lipid profiles. MATERIALS AND METHODS Clinical information of 22,103 individuals who took routine physical examinations, including that on age, gender, height, weight, triglyceride, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and data of HP infection were collected and analyzed. RESULTS H. pylori infection rate in 22,103 subjects taking routine physical examination was 44.5 %. More men tended to be infected with H. pylori than women (45.9 % vs 42.8 %; p < 0.01). The highest positive rate group was in the age group of 30-39 years (46.8 %) and the lowest rate was in the age group younger than 30 years (40.5 %). The obese had higher infection rate than the non-obese (p < 0.01). Mann-Whitney U test was used to explore the relationships between lipid profiles and H. pylori infection. There were significant associations among HDL, triglyceride and HP infection (p < 0.01). However, significant differences were not confirmed between cholesterol, LDL and H. pylori infection. CONCLUSION H. pylori infection was common among subjects receiving physical examination in Shanghai and it was most significantly associated with HDL and triglyceride, indicating that H. pylori might be a new cardiovascular risk factor (Tab. 3, Ref. 23).

The polynomial fitting method is used widely to detect cycle slips of carrier phases of GNSS for its easily computer programming and simple algorithm. But, this method is influenced by the observation errors and sampling rates. In this contribution, the polynomial fitting method and the Newton interpolation method are combined to solve those influences. In this paper, we introduce the new method theory and its mathematical model. Finally a test is taken to prove the reliable of the new method. The result shows that the new method does well in cycle-slips detection, and it reduces the calculation amount.

In order to identify each base-station in quasi-GPS ultrasonic location system, a unique pseudo-random code is assigned to each base-station. This article primarily studies the distance estimation problem between Autonomous Guide Vehicle (AGV) and single base-station, and then the ultrasonic spread-spectrum distance measurement Time Delay Estimation (TDE) model is established. Based on the above model, the envelope correlation fast TDE algorithm based on FFT is presented and analyzed. It shows by experiments that when the m sequence used in the received signal is as same as the reference signal, there will be a sharp correlation value in their envelope correlation function after they are processed by the above algorithm; otherwise, the will be no prominent correlation value. So, the AGV can identify each base-station easily.

Echo signal of radio fuze is a special transient signal whose wave parameters and arrival time are unknown. In this paper, an echo detection method of radio fuze based on discrete wavelet transform is introduced. The method adopts special wavelet basis function and scale factor, and obtain signal arriving time to realize distance measurement by the relationship that discrete wavelet coefficient of echo signal arrives peak at the corresponding time. Simulating results show that the method is feasible in radio fuze ranging application.

Solar irradiation and ambient temperature are characterized by region, season and time-domain, which directly affects the performance of solar energy based car system. In this paper, the model of solar electric cars used was based in Xi'an. Firstly, the meteorological data are modelled to simulate the change of solar irradiation and ambient temperature, and then the temperature change of solar cell is calculated using the thermal equilibrium relation. The above work is based on the driving resistance and solar cell power generation model, which is simulated under the varying radiation conditions in a day. The daily power generation and solar electric car cruise mileage can be predicted by calculating solar cell efficiency and power. The above theoretical approach and research results can be used in the future for solar electric car program design and optimization for the future developments.

By adding canards to the chined-body configuration, it's influences on wing rock motion and it's mechanism at angle of attack of 30° have been investigated through a series of experiments. Experimental results show that the asymmetric flow over the chined-body configuration, especially the flow over the windward wing during rolling motion, is influenced strongly by the flow over the canard and as a result the wing rock motion of the chined-body configuration can be suppressed finally.

The bearing load of a plane inclined sector-shaped hydrodynamic thrust bearing, under simultaneous translation and transverse vibration, is measured experimentally. The results are used to evaluate the lubrication theory solutions. Consequently, both the influences of the unsteady film inertia, measured by the squeeze Reynolds number Res, and the convective film inertia, measured by the modified Reynolds number Re*, on load amplitude and phase are investigated. It is found that the inertia-neglected lubrication solutions underestimate: (1) the oscillatory component of the bearing load by 6.5 percent at Res = 1.0 and by 1.4 percent at Re* = 1.0, and (2) the mean component of the bearing load by 0.7 percent at Res = 1.0 and by 2.0 percent at Re* = 1.0 Moreover, the fluid inertia induces an equivalent negative spring force component which shifts the phase of the bearing load by 9.5 deg at Res =1.0 and by 4 deg at Re* = 1.0 as compared to the lubrication theory predictions. Hence it can be an important consideration when designing bearings for vibration control purposes.

Particle image velocimetry (PIV) experiment technology and surface pressure measurement have been used to investigate yaw effects on vortex flow over a chined fuselage with Reynolds number of 1.87 × 105 at angle of attack α = 50° and sideslip angle β = 4°. Under condition of no sideslip, there are two symmetric leeward vortices with strong intensity. Due to the yaw‐induced corssflow, the upwind vortex is drawn closer to model surface and the downwind vortex is displaced upward and outward, and vorticities of the two vortices decrease in various degree. At the same time, the yawing condition causes the downwind vortex burst at an axial position in front of the upwind vortex. As a result, the suction effect is enhanced on upwind side and reduced on downwind side. A restoring side force forms on forebody, which indicates the chined forebody has static directional stability at high angle of attack.

Because the flight performance of aircraft is so dependent on aerodynamic efficiency of elevator, it is very important to improve the flow separation over the control surfaces at high deflection angle in order to keep the aircraft having good flight capability, especially for the modern aircraft with tailless aerodynamic configuration. A new flow control technique to improve the flow separation over the control surface by microblowing at the flow separated position is discussed in this paper. Furthermore, the effect of the various blowing parameters are also investigated in detail, and based on these studies, the parameter similarity about this flow control technique is discussed.

Support interferences always affect the accuracy of the wind tunnel experimental data. Therefore studying support interference is of significant value in practice. The double rotating shaft support is a novel way of support. In this paper, numerical simulation has been taken to investigate the effect of the double rotating shaft support system on aerodynamic forces and moments of DBM model. It is found that the support system induces the lift coefficient and the drag coefficient to decrease and the pitching moment coefficient to increase. For the parts of the model which are above the wing plane, the lift coefficient and the drag coefficient decrease. And for the parts of the model which are below the wing plane, the lift coefficient and the drag coefficient increase. For the pitching moment coefficient, the influnence is opposite to that of force.

A staphylococcus aureus protein A co-operated ELISA (SPA-ELISA) for the detection of anti-HCV-IgM has been established using HCV antigenic polypeptide, SPA-bearing germs and horseradish peroxidase labelled anti-human IgM. The specificity of SPA-ELISA has been confirmed by some substitution tests, blocking tests and destroying test with 2-mercaptoethanol. The results showed that the rate of anti-HCV-IgG in a group of patients with acute hepatitis and there were significant difference in anti-HCV-IgM was higher than that of anti-HCV-IgM detected rates between patients with acute hepatitis and those with chronic hepatitis (32.26%, P < 0.01). On the other hand, the positive rates of anti-HCV-IgM were 53.66% and 63.41% in transfusion associated hepatitis, 38.10% and 42.86% in sporadic hepatitis, 6.11% and 16.33% in people who have had active social activities, 40.00% and 10.00% in a group of blood donors respectively. Furthermore, taking into account the characteristics of HCV polypeptide used, its easiness of manipulation, and elimination of the interference of anti-HCV-IgG in sera, the new SPA-ELISA is believed to be of practical value in clinical and epidemiological studies of hepatitis C.

A study of laser processing of gallium nitride (GaN) material is reported. A pulsed KrF excimer laser at 248 nm with 20-nsec pulse width and 1 Hz repetition rate is used to etch the GaN film. We establish the material etching parameters under different environmental conditions. By changing the pulsed energy at constant pulse numbers, ablation of GaN surface was observed at threshold laser fluence about 0.3 J cm −2 . Laser etching increase with reducing environment pressure. At 1.0 J cm −2 laser fluence, the etching rate is about 35 nm per pulse at atmosphere pressure and increases to 60 nm per pulse at low pressure. The etched depth also increases with increasing laser fluence. The surface morphology of the etched surface was also investigated.

High power near-UV LEDs, with wavelengths from 365nm to 410nm, were realized with an external quantum efficiency from 12% to 45% for 365nm and 410nm, resp. We show that the vertical LED design, coupled with the Silicon sub-mount package, gives very good reliability that is suitable for many high power epoxy and polymer curing applications. UV LEDs are proven to be a good replacement for high power mercury lamps currently used in the market.

Researchers always intend to pursue the convenient and integrated tools for restoring the complexity of industrial automated systems. In this paper, a PC-based with PC visual basic-based (VB-Based) human-machine interface (HMI) is developed by using Petri nets (PN) technique for the simulation of an industrial automated system. The result brings many advantages to the reality of the automated control world. It not only reduces the restore time of the automated systems, prevents the cost of equipment malfunction, but also builds the panel of the humanity for the system. The developed sequence table has proved as an important role of control process for a discrete-event control system (DECS). This paper also discusses a systematic method to convert the sequence table to Petri nets so the barriers of the conversion technique can be easily reduced.

To explore etiology of acute exacerbation in severe chronic active hepatitis, in situ HBVDNA hybridization was carried out combined with detection of HBV markers in the serum and the liver as well as intrahepatic HDAg in 15 cases. Four subgroups were identified based on the etiological evidence: 1) 9 cases were still undergoing HBV active replication or reactivation with cytoplasmic and membraneous HBcAg expression, often associated with the hepatic necrosis foci; 2) 3 cases showed HBsAg or/and HBVDNA positivity despite absence of HBcAg expression, the membranous and homogeneous HBsAg expression being closely related with hepatic necrosis; 3) 2 cases were HDAg positive; 4) the remaining case exhibited no HBV infection evidence. All findings suggested that HBV active replication or reactivation was the major cause of the exacerbation in severe chronic active hepatitis. In addition, HBV superinfection accounted for over 10% of cases with acute exacerbation. Hepatitis A or C may contribute to some episodes of exacerbation.