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Pavement subjected to the traffic load above shakedown limit is predicted to exhibit accumulated plastic strains that eventually lead to failure within the pavement system. Shakedown theory is a valid approach to estimating the critical shakedown load level. In this study, a dynamic shakedown method for computing the shakedown limit of pavement is presented based on the lower-bound theorem of shakedown. To this end, a combined Finite element-Infinite element (FE-IE) method is utilized to calculate the dynamic elastic stress field due to rolling and sliding contact between wheel and pavement surface considering the effect of moving speed. The rolling and sliding contact is approximated by a moving Hertz distribution load, which is performed through moving vertical and horizontal body forces simultaneously modeled by thin-layered element above the pavement surface. Shakedown limits for both uniform and two-layered pavement system at various moving speeds have been investigated, respectively. It is found that the shakedown limit decreases with the increasing moving speed and then turns to increase when the moving speed exceeds the Rayleigh wave speed. This dynamic effect is more profound when the horizontal force is small. The influence of horizontal force on shakedown limit at various moving speed is also discussed. Eventually, the impact of frictional coefficient and material properties on shakedown limit for two-layered pavement is also investigated as can then be applied to the optimal pavement design.

Motion control is one of the key technologies in automatic parking system. The vehicle real-time positioning information plays a fundamental role in motion control. The automatic parking scene is essentially an low-speed unmanned scene in a small area. This paper mainly studies the vehicle positioning technology in this scene, namely the Closed- loop update of parking spot. Considering the high price of equipment used in general vehicle positioning technology, this paper selects the vehicle positioning technology with simple and low cost equipment. Firstly, the positioning accuracy of traditional track reckoning is confirmed, and the simulation with carsim & simulink is used to verify the track reckoning ability. Secondly, the method of track reckoning with speed is proposed to locate moving vehicle in real time. Finally, due to the inaccurate wheel speed of vehicle at low speed in real vehicle verification section, an improved method of track reckoning used multi-information is proposed. The method combines the advantages of traditional and wheel speed methods of track reckoning to complete the track reckoning better. The software simulations and real vehicle tests about parallel parking trajectory show that the track reckoning with multi-information fusion is superior in Closed- loop update of parking spot.

It is urgent to find an optimised therapy regimen for the control of MDR-TB globally. This study aimed to evaluate the efficiacy and safety of a combined regimen of rhIL-2 injection and standard chemotherapy within 18-month duration in a randomized controlled trial conducted in 14 centres in eastern China. From Jan. 2009 to July. 2016, 271 MDR-TB cases were enrolled and followed up in two groups, 142 cases in study group while 129 cases in control group. Clinical efficacy, safety and immune activity (Th1, Th17, Treg, IFN-γ, IL-17) among the two groups were evaluated and compared. After 24-month following up, cure rate in IL-2 group show higher than that in control group (56% VS 36%, P

We observe the photorefractivity without bias voltage or prepoling in a bifunctional photorefractive polymer. The maximum two-beam coupling gain is measured to be 126 cm−1 at zero bias voltage. The sample is considered to be poled by the photoinduced longitudinal electric field, which is formed due to the light intensity gradient along the light path. The expression of the electric field was deduced. The energy transfer direction between two writing beams and light intensity dependence of the two-beam coupling gain coefficient is predicted to be consistent with the experimental results. Furthermore, the dependence of the two-beam coupling gain coefficient on external applied electrical field is measured and this experiment verifies the existence of the photoinduced longitudinal electric field.

Photorefractive (PR) composites based on poly(N-vinylcarbozale) and azobenzene have been fabricated. Two-beam-coupling and four-wave-mixing phenomena were observed in the absence of an external electric field or prepoling. The maximum two-beam-coupling gain coefficient and the refractive index modulation were measured to be 79 cm−1 and 2.2×10−4 respectively. The all-optical-PR phenomenon is explained based on the photoassisted poling of the azo dye by the synergism of the photoisomerization and the longitudinal electric field due to longitudinal intensity gradient of writing light beams. The bi-hole-transporting system provides more charge-carrier traps resulting in improvement of PR performance.

It is discovered experimentally that, when placing a plate of dye BDN in a ring YAG laser cavity, the dye shows asymmetric control actions on the clockwise and counter-clockwise travelling waves. Unidirectional dye Q-switched operation is realized in a ring cavity based on this property without the use of Faraday rotator, polarizer and half-wave plate. A simplified theoretical analysis of this phenomenon is presented.

A novel full-functional photorefractive small molecular material, (9-ethyl-9H-carbazol-3-ylmethylene)-(4-nitro-phenyl)-amine (ECYENPA), was synthesized and its photorefractivity was studied by two-beam coupling experiments at a wavelength of 632.8 nm. The glass transition temperature of ECYENPA, as low as −5 degrees C, results in the chromophore being orientated easily at room temperature. High two-beam coupling coefficient was obtained to be 232 cm−1 at an electric field of 44.6 V/μm.

In order to disseminate photovoltaic (PV) technologies into remote rescue applications in Taiwan, a feasibility study on grid-tie PV System with battery back-up was done. A 3.2kWp back-up PV system has been installed in a remote police station (22°44′59.46″N, 120°43′38.83″E) located in the mountain region of southern Taiwan. In this paper, the design and the operational results of this PV system will be presented. This system was designed with autonomous operation of 5 days. From the actual operation experiences, it is shown that the output of the system can satisfied the demands of the emergent loads in blackout period. The DC daily mean yield was 9.01kWh/day (2.8kWh/day/kWp) during 09/18/2010∼4/30/2012, which satisfied the emergent need of 7.48kWh/day. The performance ratio (PR) was 72.8% during 12/01/2010∼ 04/30/2012 and the biggest loss was due to the maximum power point (MPP) mismatch, accounted for a 9.45% at the same period. This PV system worked very well during the attack of Typhoon Fanapi and supplied power for the mobile phones, radio communications, office lighting and rescue equipments during the blackout of 10 days.

An automatic thresholding method based on aspects of the human visual system which preserved edge structure in images is proposed. We first determine edge thresholds based on human visual perception, and then use these edge thresholds to find several edge intervals. From these edge intervals, we find the threshold value(s) at which most edge information is preserved in the thresholded image. A bilevel thresholding algorithm is first described, and then two multilevel thresholding algorithms called Nm-multilevel thresholding and mN-multistep thresholding are derived through a slight modification of the bilevel thresholding algorithm. The multistcp thresholding algorithm directly uses bilevel thresholding sequentially to select m threshold values one by one so as to speed up the thresholding process. The proposed thresholding method is simple, requiring neither an iterative operation nor edge detection.

Generation of an up to 1.5-W single-frequency and a 650-mW frequency-stabilized second harmonic at 1.06 µm has been demonstrated in a cw ring Nd:YAG laser with a pair of properly oriented KTP crystals in which the walk off between the intracavity modes has been eliminated. The frequency stability is better than 5 MHz for the second-harmonic output level of 650 mW. The fluctuation of power is less than 4%. PACS: 42.60. By. 42.65 Ky.

Nasal continuous positive airway pressure (nCPAP) usually reduces sleepiness in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). However, even with regular use of nCPAP, some OSAHS patients experience residual sleepiness (RS). The aim of this study was to evaluate the efficacy of adaptive servoventilation (ASV) on RS in OSAHS patients. The Epworth Sleepiness Scale (ESS) score was used for assessment of RS. Following correct application of 1-month auto-CPAP (APAP) treatment and exclusion for other sleepiness-associated disorders, 42 RS patients with severe OSAS were recruited. All of them received 1-week ASV treatment with auto-CS2 ventilator. Comparisons between APAP and ASV treatments were made for the following data: polysomnographic parameters including apnea hypopnea index (AHI), central sleep apnea index (CSAI), micro-arousal index (MAI), minimal pulse oxygen saturation, etc.; daytime ESS score. Compared with the parameters on day 30 of APAP treatment, there was a further significant decrease in AHI, CSAI, MAI, and daytime ESS score (P

Transparent display is one of the main technologies in next-generation displays, especially for augmented reality applications. An aperture structure is attached on each display pixel to partition them into transparent and black regions. However, diffraction blurs caused by the aperture structure typically degrade the transparent image when the light from a background object passes through finite aperture window. In this paper, the diffraction effect of an active-matrix organic light-emitting diode display (AMOLED) is studied. Several aperture structures have been proposed and implemented. Based on theoretical analysis and simulation, the appropriate aperture structure will effectively reduce the blur. The analysis data are also consistent with the experimental results. Compared with the various transparent aperture structure on AMOLED, diffraction width (zero energy position of diffraction pattern) of the optimize aperture structure can be reduced 63% and 31% in the x and y directions in CASE 3. Associated with a lenticular lens on the aperture structure, the improvement could reach to 77% and 54% of diffraction width in the x and y directions. Modulation transfer function and practical images are provided to evaluate the improvement of image blurs.

Two-mode squeezed states of light field are experimentally generated by nondegenerate parametric down conversion in an optical cavity. Noise reductions of about 30% relative to the vacuum noise level are obtained in the quiet quadrature of the electromagnetic field.

With the rapid growth of networks in size and complexity, netwok administrators today are facing more and more challenges for protecting their networked computers and other devices from all kinds of attacks. Unlike the traditional methods of analyzing textual log data, a visual interactive system called DDoSViewer is proposed in this paper for detecting DDoS kind of network attacks. DDoSViewer is specifically designed for detecting DDoS attacks through the analysis of visual patterns. We will discuss the data sources, visual structures and interactive functions that are used in the proposed visualization system. We will also discuss the advantages and disadvantages of the existing visual solutions for DDoS detection. The extraction and analysis of network data, the calculation and display of graphic elements’ attributes and the pre-characteristics of DDoS attacks are all included in the new visualization technique. The experiments showed that the new system can detect DDoS attacks effectively.