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Plug-in hybrid electric vehicle is an important measure to achieve energy saving and emission reduction. Energy management strategy is one of the most important parts in the research of PHEV, which has important influence on the performance of the whole vehicle. In this paper, a plug-in parallel hybrid electric vehicle is employed as the research object: firstly, a rule-based algorithm is established; then, an energy management strategy using fuzzy control is presented to improve the rule-based algorithm; finally, the proposed control strategies are simulated and verified under three typical driving cycles. The result shows that the proposed fuzzy control strategy can achieve a more smooth control effect to alleviate the decline rate of the battery State of Charge (SoC) and significant fuel consumption reduction could be achieved compared with the rule-based algorithm. Under certain driving conditions, fuzzy control strategy can achieve an extension of Charge Depleting (CD) phase by up to 4.45% and the reduction in energy loss can be up to 5.99%.

In the near-infrared region, we can test the blood glucose by non-invasive method. Based on this theory, combined photoacoustic principle, we had research about the simulated samples of blood glucose, measured the concentration of glucose solution. We have discussed the optimal wavelength in the near-infrared region (780-2400nm), and did the experiment repeatedly, and then analyzed data through the linear, polynomial and exponential fitting of the Generalized Least Squares, the measuring accuracy of the glucose solution had improved. These research results provide the guidance on the practice and experimental evidence for the further research of measuring.

Based on the principle of photoacoustic,blood glucose can be non-invasive monitoring of in the NIR region.The system irradiates to the glucose solution by opo laser,then the signals are received by photoacoustic probe and processed by the oscilloscope, finally imported into the computer.By the least squares method,the data repeatedly fits to make the mean square error of the glucose concentration less than 5mg/dl.The experimental results show that:photoacoustic measurement method can achieve a certain precision, with the value of further research.

Migraine is a common neurovascular disorder in the neurologic clinics whose mechanisms have been explored for several years. The aura has been considered to be attributed to cortical spreading depression (CSD) and dysfunction of the trigeminovascular system is the key factor that has been considered in the pathogenesis of migraine pain. Moreover, three genes (CACNA1A, ATP1A2, and SCN1A) have come from studies performed in individuals with familial hemiplegic migraine (FHM), a monogenic form of migraine with aura. Therapies targeting on the neuropeptids and genes may be helpful in the precision medicine of migraineurs. 5-hydroxytryptamine (5-HT) receptor agonists and calcitonin gene-related peptide (CGRP) receptor antagonists have demonstrated efficacy in the acute specific treatment of migraine attacks. Therefore, ongoing and future efforts to find new vulnerabilities of migraine, unravel the complexity of drug therapy, and perform biomarker-driven clinical trials are necessary to improve outcomes for patients with migraine.

We describe the first case of a dural arteriovenous fistula of the anterior cranial fossa successfully treated with transarterial embolization using Onyx-18.

Photoacoustic tomography (PAT) is presented to in vivo monitor neovascularization in tumour angiogenesis with high resolution and high contrast images in a rat. With a circular scan system, the photoacoustic signal, generated by laser pulses at a wavelength of 532 nm from a Q-switched Nd:YAG laser, is captured by a hydrophone with a diameter of 1 mm and a sensitivity of 850 nV/Pa. The vascular structure around the rat tumour is imaged clearly, with optimal contrast, because blood has strong absorption near this wavelength. Serial noninvasive photoacoustic images of neovascularization in tumour angiogenesis are also obtained consecutively from a growing tumour implanted under the skin of a rat over a period of two weeks. This work demonstrates that PAT can potentially provide a powerful tool for tumour angiogenesis detection in cancer research. It will bring us closer to clinical applications for tumour diagnosis and treatment monitoring.

Honing process is widely used to improve the surface finish of hardened gears. The existing challenging for this manufacturing process includes its low efficiency and excessive forces exerted on both of engaged gears and tools. Ultrasonic assisted honing has a number of superior advantages over the traditional methods. This paper presents a new theoretical method for the parameter determination of non-resonant gear transformer, which is the key component of ultrasonic assisted honing systems. A mathematical model for the ultrasonic assisted honing system is first established and solved with different design parameters by using the numerical method. The numerated results then are verified by the FEM analysis and experiments. It is found that the proposed method is effective and useful. The details will be addressed in the paper.Copyright © 2014 by ASME

In this paper, a backstepping control design is presented for the longitudinal dynamics of a hypersonic flight vehicle. The GHV dynamics system is first decoupled into two subsystems, velocity subsystem and altitude subsystem. Then, the two subsystems are transformed into the strict-feedback forms, and on the basis of which the velocity controller and altitude controller are separately designed. Next, a comprehensive Lyapunov function based stability analysis is chosen to show that the tracking errors are semi-global uniformly bounded and the signals of the system are bounded. Numerical simulation results show that the proposed controller provides satisfied control performance.

Under the extremely limited space experimental conditions, it's still a challenge for us to make the small sample of the data ensure the validity of experimental results in a certain confidence interval. We used the theory of small sample data analysis to design and synthesize strategies in order to be adequate for reasonably good knockdown of the number of samples required for the experiment. And we applied and verified the method to determine the number of operation sEMG signal samples by using an example of space ergonomics experiment. Finally, we analyzed the applicability and reliability of this method for series of experiments and looked forward to the trend of the research directions.

To effectively resolve the automatic recognition problem of analog measuring instruments, a reading recognition method based on improved Hough transformation is proposed. Firstly, the paper presents the image preprocessing operation. In order to make the image filtering better, an improved adaptive median filter method is adopted. Secondly, we explains in detail the recognition principle for the pointer angle using the improved Hough transform. And the pointer's reading is got using the linear relationship between scale and angle of instrument dial revolutionary. In order to further improve the recognition accuracy, as to the situation that pointer completely coincides with the whole tick, late correction will be done. Finally, the automatic recognition software is written in VC++6.0 IDE, and complete the recognition experiment for the AC voltmeter. The experimental results show that the method is very valid for the pointer angle recognition. In addition, the advantages of this study are as following: simple algorithm, good real-time and high precision.

Based on the theory of multi-body system and the motion of CNC gear hobbing machine, a volumetric error model for NC gear hobbing machine has been built, and the tooth surface equation is established, which includes original position errors and motion errors. Thus a preferable method is provided for carrying out real-time measurement and compensation, and further studying the effects that error factor takes on gear machining.

Regional comprehensive corridor takes on the characteristics of heavy transport demand and supply, and consists of many travel modes; meanwhile, competition is severe among different trip modes. In order to avoid vicious competition so that transportation market is disturbed, multi-objective and nonlinear programming model is built up, which is based on the maximization of unity of traveler. The objective of model is minimization of distance between practical capacity coefficient and ideal capacity coefficient. Multi-objective is transferred into single objective by TOPSIS method before model is solved. The transformed objective function is multi-peak function, so niche GA is introduced into solving the problem to obtain all of optimal solution. K-means clustering is adapted to classify the set of optimal solution. The centre of gravity of each cluster is taken as value of decision variables. At last a numeric example demonstrates the validity and feasibility.

The traditional CBIR (Content based image retrieval) global descriptor can't extract local features effectively, while the SIFT (Scale Invariant Feature Transform) algorithm only focus on local object features matching, and can not satisfy the need of fuzzy CBIR queries based on visual feeling. In view of this contradiction, an approach is proposed based on image salient region, in which the SIFT algorithm and the traditional CBIR color descriptors are combined, the entropy of salient point is used to distinguish the salient and non-salient regions of image. We use centroid weighted histogram and dominant color descriptor of MPEG-7 to describe the salient and non-salient region respectively, which not only effectively extract the local features of image objects, but also overcome the SIFT algorithm for high dimension, and vulnerable to interference with the global features. Experiments show that for general image retrieval application, the proposed method has better retrieval performance, with better robustness for geometric and perspective transform.

Image watermark resistant to geometric attacks is the focus and difficulty point in the current research on watermarking. This paper proposes a Wavelet-domain watermarking algorithm against geometric attacks based on the SUSAN feature points matching. The algorithm embeds watermarks into each sub-band of the wavelet coefficients of the host image with different strength adaptively adjusted in terms of the gray level of them. The choice of the embedding strategy effectively guarantees good transparency and strong robustness of the watermark. Furthermore, the paper improves the SUSAN operator, to extract the feature points robust to geometric distortion from the watermarked image. Before watermark detection, it uses the transformation of the corresponding points to correct geometric distortion, which ensures successful extraction of the watermark. Experiment results show that the proposed algorithm has good transparency, and it is also robust to common image processing and geometric attacks.

The development trend of gear hobbing machine which includes CNC, high-speed, high-accuracy, direct-drive and environment protection, is discussed firstly, and design principle of direct-drive gear hobbing machine of dry-cutting, which break through traditional structure design theory of gear cutting machine, is put forward. Direct-drive gear hobbing machine adopts the technologies of build-in motor spindle and DDR torque motor which directly drive the revolve of cutting tool and worktable, and completely cancels high precision gears and worm wheel in the machine transmission, so to realize that power source directly drive work parts of machine tool. The key technologies of direct-drive gear hobbing machine of dry-cutting, such as general layout technology, bed and chip removal system design technology, hob spindle and workpiece spindle structure design technology, are analyzed and studied in detail. It is of theoretic significance and practical value, for the study and development of direct drive gear-cutting machine of high-speed and high-precision.

The accurate motion compensation is important for gaining high resolution of imaging for some characteristics of missile-borne SAR, such as high speed, motion pose errors, high real-time and so on. The paper first introduces the two types of errors of missile-borne SAR and their effects to image. Subsequently, the first class of error, including normal face error and error along flight route, is described in details due to its serious effects to imaging. At the same time, the corresponding compensation algorithms are also showed. Finally, the paper gives the simulation results that the phase compensation to Doppler phase errors resulting from slant distance can improve the imaging resolution effectively. In the meantime, the phase compensation to Doppler modulation frequency errors resulting from speed error ameliorates Doppler mismatching. The resolution of the system reaches two meter.

To aim at the problem of blind detection of low-SNR direct-sequence spread spectrum (DS/SS) signals, this paper presents that the DS/SS signal has fractal characteristic, and uses the variance fractal dimension trajectory (VFDT) approach to detect the DS/SS signal contaminated by noise. The theoretic analysis and computer simulation results show that this algorithm can detect DS/SS signals at a lower SNR and runs more quickly than the usual detecting methods like the time-domain correlation detecting method, the cepstrum detecting method, and so on.

A photoacoustic system with an annular transducer array is presented for rapid, high-resolution photoacoustic tomography of animals. An eight-channel data acquisition system is applied to capture the photoacoustic signals by using multiplexing and the total time of data acquisition and transferring is within 3 s. A limited-view filtered back projection algorithm is used to reconstruct the photoacoustic images. Experiments are performed on a mouse head and a rabbit head and clear photoacoustic images are obtained. The experimental results demonstrate that this imaging system holds the potential for imaging the human brain.

Paper Withdrawn Because Already Published in AJNR American Journal of Neuroradiology 28: 1769 - 70 - October 2007.