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The human vestibule function trainer studying in this paper is based on the first generation of spherical 4R space mechanism. Using the 3D modeling software UG and its integrated simulation analysis tool UG MOTION, the spherical 4R space mechanism and its common form are used as research objects. UG software's powerful modeling ability enables 3D solid modeling of the members and main parts, completes the virtual prototype modeling, and uses UG MOTION to simulate the overall motion of the virtual prototype. By adding the balance block method, the dynamic balance optimization design is completed. Then the motion simulation is carried out, the analysis results, and the balance problem is well optimized.

Background Previous studies demonstrated that miR-539 play an important role in the carcinogenesis of some cancers. The aim of the present study was to determine the role of miR-539 in the pathogenesis of Wilms' Tumor (WT). Methods The expression level of miR-539 was measured by qRT-PCR in 42 WT tissues and SK-NEP-1 cell line. Protein expression of genes (E-cadherin, N-cadherin, Vimentin, Notch 1, Notch 3 and JAG1) was assessed by Western blot. The function of miR-539 was investigated in SK-NEP-1 cells by MTT and Transwell assays. The relationship between miR-539 and JAG1 was verified by a dual luciferase assay in SK-NEP-1 cells. Results The expression level of miR-539 was significantly decreased in WT tissues. Downregulation of miR-539 was closely related to NWTS-5 stage, lymph node metastasis and histological type of WT patients. Furthermore, low miR-539 expression was associated with a shorter overall survival rate in WT patients. In vitro, overexpression of miR-539 suppressed proliferation, migration and invasion of SK-NEP-1 cells. In addition, JAG1 was a direct target of miR-539. MiR-539 inhibited the development of WT by inhibiting JAG1-Notch1/3 expressing and blocking EMT. Conclusion MiR-539 inhibited the progression of WT through downregulation of JAG1 and Notch1/3.

We carry out comprehensive optoelectronic optimization of mode selective converter used for the mode division multiplexing, based on liquid crystal on silicon (LCOS) in binary mode. The conversion error of digital-to-analog (DAC) is investigated quantitatively for the purpose of driving the LCOS in the application of mode selective conversion. Results indicate the DAC must have a resolution of 8-bit, in order to achieve high mode extinction ratio (MER) of 28 dB. On the other hand, both the fast axis position error of half-wave-plate (HWP) and rotation angle error of Faraday rotator (FR) have negative influence on the performance of mode selective conversion. However, the commercial products provide enough angle error tolerance for the LCOS-based mode selective converter, taking both of insertion loss (IL) and MER into account.

For the optical fiber biosensor made of combination optical fiber tip, the effects of the refractive index RI of outer medium and the geometrical parameters of combination optical fiber tip on two important quantities have been investigated. One factor is the total intensity of the evanescent wave into fluorescent layer through core-medium interface; the other is the intensity of the fluorescence signal transmitted from fluorescent layer to measurement end. Theoretical investigations show that the two quantities are dependent upon the RI of outer medium, and the total intensity of the evanescent wave into fluorescent layer increases with the increase of taper angle, and the fluorescence signal arrived at the measurement end gets larger value for shorter fiber tip when the RI of outer medium is smaller than the RI of fiber core.

Optical Fiber Vibration pre-Warning System (OFVWS) is widely applied to pipeline transportation, defense boundary and military base. One of its key technologies is signal feature extraction and vibration source identification. However, some harmless vibration signals often affect the reliability of this identification process due to the false alarms. Therefore, it is very important to identify various harmless vibration signals effectively. In this paper, we analyze the energy distribution feature of nature raindrop vibration signal detected by optical fiber. Based on this analysis, we develop an energy information entropy model and an approach to identify the harmless raindrop vibration signal. Study shows that the nature raindrop vibration signal can be detected and identified automatically by extracting the energy information entropy value and combining with the statistical detection method. The field tests result also showed that this approach based on energy information entropy model is able to effectively identify harmless raindrop vibration signal. Its identification probability is high and its false alarm and false recognition probability is low, hence the working performance of the OFVWS can be improved by using the presented approach.

In this paper, we constructed a low-cost acceleration monitoring system based on a rectangle cantilever beam (RCB), two fiber Bragg gratings and the light intensity measurement method. To do this, we investigated the minimum natural frequency of RCB and the dependence relationship of the strain of the measurement point and its change rate with respect to the acceleration amplitude upon the inclination angle of the sensor, and given the quantitative relationship between the amplitude of AC voltage of monitoring system versus the acceleration amplitude and the inclination angle of the sensor. Finally, we have finished a series of vibration monitoring experiments, and the experiment data are consistent with the theoretical equations.

Calcium bismuthate (CaBi 6 O 10 /Bi 2 O 3 ) composites synthesized using a simple deposition method were used as visible-light driven photocatalysts for dye degradation in polluted water and their activities were investigated. The photocatalysts were characterized via X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, Raman spectroscopy (Raman), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and UV–vis diffuse reflectance spectroscopy (DRS). The photocatalytic activity of the CaBiO composites was evaluated through the decomposition of methylene blue in an aqueous solution under visible light irradiation (>420 nm). The CaBi 6 O 10 /Bi 2 O 3 binary semiconductors exhibit better photocatalytic properties compared with those of the single-phase CaBi 6 O 10 or Bi 2 O 3 . Based on the results of the energy band position calculation and the terephthalic acid photoluminescence (PL) probe experiment, the effective electron–hole separation in the two semiconductors is considered the cause of the high activity.

A novel photocatalyst CaBi 6 O 10 with flower-like morphology was prepared by a simple impregnation–calcination method and investigated by techniques such as XRD, Raman, SEM, BET, DRS, and density function theory (DFT). Results reveal that CaBi 6 O 10 is responsive to visible light below 537 nm (E g = 2.31 eV). In addition, CaBi 6 O 10 presents broader conduction band than Bi 2 O 3 , which favors the mobility of photo-generated electrons in CaBi 6 O 10 and contributes positively to the photocatalytic reaction. The good photoabsorption and the special electron structure were considered as the origin of the high activity of CaBi 6 O 10 in methylene blue photodegradation.

This paper presents a novel visible-light-driven catalyst, a SO42–/MoOx/MgF2 composite, which was synthesized by a simple solution method. Multiple techniques, including Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and diffuse reflectance spectroscopy (DRS) were applied to investigate the physical and photophysical properties of the catalysts. The photocatalytic activities were evaluated in the degradation of acetone in gas phase. In the photodegradation of acetone, the highest conversion was obtained over a catalyst containing 5 mol % molybdenum. The XRD and Raman characterizations indicate that the molybdenum oxide was highly dispersed in the MgF2 matrix. These MoOx species might be the active sites of the catalysts, which is the reason for the visible-light response of the composite catalyst. The MgF2 matrix acts to isolate the MoOx species and retar...

A VDyOx (V2O5/DyVO4) composite photocatalyst was prepared using a simple solution method. The powders were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) method, Raman spectroscopy (Raman), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), UV–vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. Visible light-induced photocatalytic activities of the powders were evaluated by the degradation of acetone. Results generally show that the binary semiconductors V2O5/DyVO4 with matching band potentials exhibit better photocatalytic properties compared with those of the single phase V2O5 or DyVO4. An acetone conversion of 91.6% was achieved over V1.5Dy1Ox composite photocatalyst under visible light irradiation. Effective electron–hole separation in the two semiconductors is believed to be mainly responsible for the increased photocatalytic performance of composites. The performance of the VDyOx composite catalyst can be further improved by loading a small amount of Pt. In addition, the Pt doped V1.5Dy1Ox catalyst was also proven to be efficient in the photodegradation of 2-propanol and benzene.

This article presents a novel visible-light-driven catalyst, an LaVO x composite that was prepared from La(NO 3 ) 3 and NH 4 VO 3 solutions. The visible-light-induced photocatalytic activity of this composite was evaluated by the degradation of acetone. Results indicate that the LaVO x composite exhibits high activity for acetone photodegradation. The highest acetone conversion (93.1%) was obtained with the La 1 V 1.5 O x catalyst. Its photo-activity and ability for complete oxidation could be enhanced further by doping with a small amount of the metal platinum. Physical and photophysical properties of the LaVO x composite catalysts were evaluated by X-ray diffraction (XRD), the Brunauer–Emmett–Teller (BET) method, Raman spectroscopy (Raman), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), UV–vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. Based on the results of this investigation, the coupling effect of m-LaVO 4 and V 2 O 5 was identified as generating the high activity in catalysis.

In order to solve the low discrimination of image representations in complicated duplicate image detection, this paper presents a complicated duplicate image representation approach based on descriptor learning. This approach firstly formulates objective function as minimizing empirical error on the labeled data. Then the tag matrix and the classification matrix of training dataset are brought into the objective function to ensure semantic similarity. Finally, by relaxing the constraints, we can get the learning hashes. The learning hashes are used to quantify local descriptors of images into binary codes and the frequency histograms of binary codes are as image representations. Experimental results demonstrate that compared with the state-of-the-art algorithms, this approach can effectively improve the discrimination of image presentations by introducing semantic information.

Face recognition aims at endowing computers with the ability to identify different human beings according to their face images. However, recognition rate will decrease sharply when it refers to the non-ideal imaging environments or the incorporation of users, such as illumination, pose, expression variations and so on. Besides, it will be also influence the recognition results when the database is too large or small. Sparse representation based classification for face images has been one of efficient approaches for face recognition in recent years. Discrimination performance by using the sparse representation can also be applied to the face recognition, and any test sample can be expressed as a linear span of the all training samples. Experimental results show that face recognition method based on sparse representation is comparable to others.

To analyze the typical and non-typical magnetic resonance imaging (MRI) findings of neonatal hypoglycemia encephalopathy (NHE).The clinical data and MRI findings of 20 cases with NHE were retrospectively evaluated.Among them, blood glucose values were ≤ 1.4 mmol/L (n = 18) and 2.1 mmol/L (n = 2). And 13 cases had recurrent hypoglycemia. The major clinical symptoms included convulsion, poor response, cyanosis and apnea. The typical MRI findings of abnormal signal in occipital or parietal cortex were found in 9 cases. And the involvement sites were corpus callosum (n = 4) and posterior limb of internal capsule (n = 1). Another 11 cases revealed non-typical MRI findings of damaged brain regions, involving splenium of corpus callosum (n = 8), white matte along lateral ventricle (n = 6), extensive cortical or subcortical white matter (n = 5), internal capsule (n = 3), centrum semiovale (n = 2), globus pallidus (n = 1), local cortex (frontal lobe) (n = 1), pons (n = 1), unilateral hippocampus (n = 1) and bilateral thalamus and midbrain, brain stem and medulla oblongata (n = 1).The typical MRI findings of NHE show abnormal signal in occipital or parietal cortex. And non-typical manifestations involving multiple brain areas may be observed in cases of severe NHE.

A compact temperature sensor based on a simple nonadiabatic microfiber loop is demonstrated experimentally using nonadiabatic microfiber loop. High sensitivity within a large temperature range can be obtained utilizing a microfiber with 20mm length.

In this paper the working principle and application status of distributed optical fiber temperature sensor, amplified spontaneous Raman scattering phenomenon and its time-domain characteristics are analyzed. A new measuring principle based on amplified spontaneous Raman scattering light pulse signal temperature effect is presented, and is applied to distributed optical fiber sensor systems. Noise inevitably exists in data collected by distributed optical fiber temperature sensing systems. According to the needs of high-temperature oil well testing, distributed high temperature single-mode fiber sensors and detection equipment are designed, and gives two-dimensional data of oil well temperature testing. Because of the weak Raman backwards scattered signal and serious noise disturbance, multi-resolution wavelet analysis and reconstruction method are adopted for the denoising of testing signal.

We designed a novel ultrahigh-sensitivity pressure sensor based on a surface plasmon resonance (SPR) fiber optical tip embedded in a designed polymer-filled metal cylinder with an opening on one side. The calculated pressure sensitivity is dependent on two factors. One factor is the derivative of the resonance wavelength of SPR-based fiber optical sensor with respect to the refractive index of surrounding medium; another factor is the derivative of refractive index of polymer with respect to the pressure. For the polymer with Young's modulus of 1.0 MPa, average vary rate of resonance wavelength with pressure of 1.75 × 103 nm/MPa can be obtained.

A vibration monitoring system based on light intensity measurement has been constructed, and the designed accelerometer is based on steel cantilever frame and dual fiber Bragg gratings (FBGs). By using numerical simulations for the dual FBGs, the dependence relationship of the area of main lobes on the difference of initial central wavelengths is obtained and the most optimal choice for the initial value and the vibration amplitude of the difference of central wavelengths of two FBGs is suggested. The vibration monitoring experiments are finished, and the measured data are identical to the simulated results.

As internet has become one of the most important access to information for peoples daily life, ensuring the authentication of the images transmitted in internet is of great importance. However, current image identifying technology can not satisfy the requirement on efficiency and accuracy of mass image authenticating in the internet environment. Regarding this problem, this paper proposed a SVM based image identifying algorithm which can be deployed in the network environment with the help of cloud computing architecture. With the algorithm described, mass images can be crawled from internet, the identifying model can be trained automatically and new coming image can be authenticated swiftly.

Moving mass control implements the maneuver control of vehicle through moving the movable slide inside vehicle in order to move the mass center position. In this paper, take missile as an example, based on the derivation of six degree of freedom (6-dof) model of mass moment missile, combined with the law of parameter variation of aerodynamic and speed during missile flight, combined with virtual simulation technology, to establish a virtual reality simulation for high supersonic speed vehicle's control of moving mass model, and provide necessary foundation for the next further study of moving mass control.