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In order to further improve the accuracy of age estimation, a locally adjusted age estimation algorithm based on deep learning and directed acyclic graph SVM is proposed. In the training phase, SE-ResNet-50 network pre-trained by the VGGFace2 dataset is first fine-tuned. Once the network converges, and the vector consisting of the parameters of the last fully connected layer is used as a representation and train multiple One-Versus-One SVMs. In the test phase, we first sent the face image to be estimated into SE-ResNet-50 to obtain a rough age estimation value, then set the specific neighborhood, and finally combined the trained SVM into a directed acyclic graph SVM and set specific neighborhood with the global estimate as the center for accurate age estimate. In order to show the universality of the proposed coarse-to-fine or/and global-to-local method, experiments were carried out on MORPH and AFAD images of different races, and the results verified the effectiveness of the algorithm.

The subsea observation network has become an indispensable means of ocean exploration worldwide. However, the scale of the subsea observation network is limited by the power supply voltage and power level. Hence, to promote the development of a subsea observation network, this paper investigates the underwater high voltage DC-DC converter (HVC), which greatly improves the voltage and power level of the subsea observation network. The traditional series-parallel converter based on multi-module is faced with many technical problems, such as difficult transformer isolation, many fault points, low power density under higher input voltage level, and higher output power. The subsea HVC of this paper adopts a modular multilevel resonant DC-DC converter. The main circuit of HVC is designed in detail, including a module circuit, a resonant circuit, and a control scheme. Through the combination of the sub-module removal voltage regulation and closed-loop control, the converter can still output a stable voltage of 375 V when the input voltage changes. The modular sub-module and centralized transformer structure enables the converter to isolate high voltage easily, small volume, and high power density. The simulation and experiment results show the proposed HVC meets the design requirements and has good application prospects. It can be applied to submarine power transmission and distribution needs because of its wide range, large transformation ratio, and high efficiency.

Cabled seafloor observatories play an important role in ocean exploration for its long-term, real-time, and in-situ observation characteristics. In establishing a permanent, reliable, and robust seafloor observatory, a highly reliable cable switching and fault isolation method is essential. After reviewing the advantages and disadvantages of existing switching methods, we propose a novel active switching method for network configuration. Without additional communication path requirements, the switching method provides a way to communicate with a shore station through an existing power transmission path. A coded voltage signal with a distinct sequence is employed as the communication medium to transmit commands. The analysis of the maximum bit frequency of the voltage signals guarantees the accuracy of command recognition. A prototype based on the switching method is built and tested in a laboratory environment, which validated the functionality and reliability of the method.

With the continuous development of science and technology in our country, big data technology is becoming more and more mature. In recent years, the application of computer software in our country is more and more extensive. As an important part of social production, it is of great significance to strengthen the research of computer software technology. Computer technology, as one of the landmark technologies in the 21st century, has a direct relationship with social production and people’s quality of life. Therefore, this paper focuses on the application of computer software technology in the era of big data, to improve the data processing capacity and strengthen the economic benefits of social production. Therefore, it is of great significance to strengthen the application of computer software technology in the era of big data.

In practical applications, the signal-to-noise ratio (SNR), reliability, and the long-term stability of wavelength modulation spectroscopy (WMS) system is limited by the non-absorption transmission loss. In this investigation, we report on a signal recovery method to remove the impact of non-absorption transmission loss based on an automatic gain closed-loop control. The deviation of the WMS system with the introduced signal recovery method has been observed to be below 4.27% under the non-absorption transmission loss which varied from 0 dB to −6.02 dB, and is about 13 times lower than the ordinary system. The proposed method is suitable for promoting the reliability and stability of WMS system under rigorous circumstances. Besides, it has the potential value in the multi-point detection or to achieve a higher SNR.

Introduction Spinal pedicle screw internal fixation has been widely used in adult spine injury fixation. Due to being in a period of continuous growth and development, the spine of children at different ages shows different characteristics from adults in terms of anatomy, physiological function, and biomechanics. Furthermore, because the pedicle of children is small, has large anatomic variation, and has complex adjacent relationships, the surgical risk is extremely high. How to improve the screwing accuracy is the key to the success of children's pedicle internal fixation. Therefore, applying the concept of digitized and individualized screwing will be of great significance to children's pedicle screwing. Aim To investigate the morphologies, development patterns, and aging characteristics of the lumbar vertebral pedicle (LVP) in children aged 6-11 years, and to provide a theoretical basis for screw implantation and related biomechanical studies. Material and methods A total of 60 children aged 6-11 years were selected for the intergroup measurement and statistical analysis of their lumbar diameter, pedicle diameter, screw canal length (SCL), etc. Results Generally, the vertebral foramen diameter (ID), sagittal diameter (SD), pedicle width (PW), and SCL as well as the pedicle height (PH) exhibited an increasing trend with age and increasing vertebral sequence among children aged 6-11 years. Conclusions By observing the LVP in children using 3D digital reconstruction technology, the morphology of the spinal canal and pedicles at different lumbar segments showed obvious development patterns, and the best treatment protocol should be selected according to the LVP characteristics in clinical applications.

An underwater profiler is one of the popular platforms for ocean observation. Due to energy limitations, conventional underwater vehicles have a short life span, which cannot meet the needs of long-term ocean exploration. Therefore, there is a growing interest in using ocean energy such as ocean thermal energy and wave energy for driving. This study aimed to investigate an energy-saving and ocean thermal energy (OTE)-powered buoyancy driving system of the ocean profiler. The purpose of this study was to explore an ocean profiler buoyancy driving system powered by ocean thermal energy (OTE). According to the seawater profile temperature gradient, an OTE-powered electro-hydraulic control system was designed, and the dynamic characteristics of this system are simulated and analyzed by using the power bonding diagram method. Based on the results conducted from lake tests, this profiler possesses the self-driving capability for using OTE perfectly. This research can provide important guidance for the design of the buoyancy drive system of underwater vehicles.

The cabled seafloor observation network, which provides abundant power and broad bandwidth to seafloor scientific packages, has become one of the most efficient ocean exploration methods because of its long-term, real-time, and sustained presence. However, node failure or maintenance may shut down the system until the situation is cleared. An active node switching method based on discrete-voltage intervention is proposed to establish a reliable and robust underwater electrical network that allows the system to operate partially amid node failure or maintenance. This method switches a specific node on/off from the network whenever necessary. The main structure and operating mechanism of this switching method are presented in this paper. A prototype was established, and several tests were performed in a laboratory to validate its feasibility and reliability. The prototype was then integrated into a pool-testing underwater network that included a 50-km electrical/optical submarine cable between the base station and the junction box. The test results demonstrated that the active node-switching method can efficiently and reliably fix node failure emergency situations for cabled ocean networks.

Background: Pedicle screw technique is commonly used treatment of adult spinal trauma, tumor, degeneration. The application of pedicle screws is very challenging in children because children have a fast growing spine and spinal pedicle morphology of children and adult has large difference. 3 D reconstruction individual navigation templates improve the success rate of pediatric pedicle screw system. This study is aimed to provide a precise method for lumbar spine pedicle screw placement in children using computer-aided design and rapid prototyping technology. Materials and Methods: Computed tomography (CT) scans of cadaver specimens of 4 children were obtained, and the raw data were reconstructed using three-dimensional reconstruction software. Pedicle screws were placed using the conventional method or by using individually designed navigation templates based on the principles of reverse engineering and rapid prototyping technology. Results: We evaluated the accuracy of the pedicle screws placed using the two methods by CT scan. Ten navigation templates were designed for placement of 20 lumbar pedicle screws in the navigation group, and CT scan confirmed that all the screws were placed accurately in the corresponding pedicle. Conversely, of the 20 lumbar pedicle screws placed using the conventional method, 3 screws perforated the pedicle. The findings showed that lumbar pedicle screw placement was successful using navigation templates in children. Conclusions: This technique is simple, easy to master, and allows personalized screw placement, thus providing a new and feasible method for lumbar pedicle screw placement in children.

A novel high-precision measurement method for measuring roll is presented. The pentagonal prism and corner-cube prism are used as splitting element and sensitive element, respectively. A pair of parallel collimated beams generated by a pair of splitting pentagonal prisms is incident upon the target moving along linear guide. Two beams returning from two corner-cube prisms on the target reach two four-quadrant photoelectric detectors (QD 1 and QD 2 ), respectively. So the roll can be measured by differential measurement based on QD 1 and QD 2 . Further, the measurement resolution can be doubled and resistance to common mode interference can be enhanced, by adopting common-path structure based on the polarization splitting prisms. Feasibility of the method is verified by theoretical analysis and experiments. When the system parameters apply to the values supposed, for the roll, the angular resolution can reach to 0.1″, and measuring accuracy is about 1″.

Frame interpolation attempts to generate intermediate frames given existing ones, which is challenging because of complex video scenes and motion. Standard methods first estimate motion between two continuous frames and then synthesize new ones. In this paper, we propose a novel frame interpolation method based on a video synthesis approach deep voxel flow (DVF). In DVF, a deep convolutional encoder-decoder predicts 3D voxel flow, and then a volume sampling layer synthesizes the intermediate frame guided by the flow. To improve the accuracy of voxel flow, we employ recurrent convolutional layers (RCL) in the encoder-decoder module to refine the flow step by step, called DVF-RCL. We also incorporate perceptual loss to increase the visual quality. Experiments demonstrate that our method greatly improves the performance of original DVF and produce results that compare favorably to state-of-the-art methods both quantitatively and qualitatively.

With time synchronization becoming an important feature of cabled ocean observatory networks, an innovative approach using the IEEE 1588 standard featuring the precision timing protocol (PTP) is proposed. Both boundary clock (BC) and transparent clock (TC) based on PTP are analyzed, and the framework of a synchronization system mainly consisting of a shore station section, a junction box layer, and a science instrument layer is presented. The proposed time synchronization system was applied and tested on a laboratory setup of the Experimental Underwater Observatory Network System of China. Results indicate that the time accuracy of the proposed system satisfies the needs of the observatory networks either in BC mode or TC mode, and the time accuracy is better in TC mode, especially when the network structure becomes more complex.

Ocean observatory networks have been investigated and developed and are receiving considerable attention in the 21st century. As intermediate processing nodes, junction boxes (JBs) are essential sections of ocean observatory networks. This paper explored the key technologies of JBs for Chinese experimental seafloor observatory networks, including industrial control, Ethernet communication, and time synchronization technologies. Specific functional verifications of each section were conducted in the laboratory prior to sea trials. The JBs were packaged in a frame and were deployed in the East and South China Sea. Results of the laboratory and sea trial experiments demonstrated that the examined technologies were effective and could provide valid guarantee to the long operation of the JBs.

The cotton′s maturity and fineness are the key parameters to evaluate the cotton fibers quality.The indirect parameters measurement can not accurately evaluate the cotton fiber′s quality.A direct method based on the optoelectronic measurement of Fraunhofer diffraction was presented.The measurement results were compared between the microscope and the optoelectronic setup.The results show that two methods have the good correlation(R=0.956,and SD=0.332).The optoelectronic technique can assess the cotton fiber′s maturity in the lab.

Ginning cotton qualities influence seriously the quality of textiles. Ginning cotton is always mixed with various defects during the picking, transporting, storing, and processing. This paper proposed one novel method to solve the problems of intensity changes of light source. Firstly, the properties of cotton and defects are studied. Secondly, the setup of measuring system is introduced and image processing algorithm is proposed. Finally, experimental results are discussed and the optimal drive circuit of light sources is designed. The results show the measuring system can meet with the requirement of nondestructive measurement of ginning cotton quality. The experimental results show that the accuracy of the cotton defect's measuring system is above 90%, and the measuring time is within 3 second. This system can meet with the requirement of fast measurement of cotton ginning qualities in field.

Laser collimation technology is widely applied in the positioning and measurement. Because the accuracy is affected by the laser beam drift, so laser beam drift compensation is necessary. The complexity of sources and forms of laser beam drifts affect the compensation effect. The noise signals caused by electronic noise, laser source, and environment, are analyzed in detail. Further, the parallel drift and angular drift of various types of beam drift signals are estimated and the effectiveness of low-pass filter and mean process are verified and compared. This study is beneficial to analyzing various types of noise signals and building a more effective compensation models for laser beam drift.

We present a fully automated method to segment the interventricular septum from cardiac MR images in this paper. By introducing the circular Hough transformation our model can automatically detect the contours of left ventricle as circles used as the initialization. The interior and exterior energies are weighted by the entropy, which improves the robust of the evolving curve. Local neighborhood information is used to evolve the level set function, which can reduce the impact of the heterogeneous grays inside of regions and improve the segmentation accuracy. The adaptive window size is utilized to reduce the sensitivity to initialization rather than a fixed window size. The Gaussian kernel is used to not only ensure the smoothness and stability of the level set function, but also eliminate the traditional Euclidean length term and re-initialization. Finally, we segment the septum automatically by the classical segmentation methods combined with anatomical location information. Extensive experiments indicate that the superior performance of the proposed method over the state-of-the-art methods in terms of both good robustness and high efficiency.

The diffraction methods were used to measure thin wires or fibers with some advantages. The method was based on Fraunhofer diffraction principle. The diffraction pattern can be detected by the Charge Coupled Device (CCD). CCD often produced the noise in the diffraction pattern and gave rise to the measuring error for the ambient disturbance. After theoretical simulation and analysis, the wavelet analysis was prior to the FFT method. The five repetition measurements of the diffraction pattern signals of the normal fiber were obtained. The five repetition measuring results showed that the wavelet analysis method was better than the FFT method to remove the noise from the signal. The diameter of the cotton fibers can assess the cotton’s qualities, so this research was very advantageous to the next study about the diameter measurement of the cotton fiber.

The flange thickness and rim inside thickness of the wheelset are key parameters that influence the wheel-rail contact. With the speed continuous increase of the rail vehicles, the wear of wheelset is becoming more and more serious, thus accelerating the changes of wheelset’s flanges, which will certainly bring security hidden troubles to the operation of railway, so it is very important to realize dynamic measurements of the wheelset’s flange thickness and rim inside thickness. This paper proposes a novel real-time measurement method to wheelsets based on the image processing. This system based on the triangular principle uses CCD (Charge-coupled device) to obtain the information of the wheelsets. In this system, the flange thickness can be uncontacted measured in real time. The standard deviation of the rim inside thickness is 0.47mm and that of the flange thickness is 0.635mm, and the error range is ±0.8mm, and ±1.0mm, respectively. When the train passes through the measurement system at the speed of 5km/h, the measurement results show that the measurement system can meet the measuring requirement on line.

The novel method to improve the limiting capability of DC reactor type superconducting fault current limiter (SFCL) by using mutual inductor is presented in this paper. The configurations of the SFCL are described in detail, in which both a superconducting and a mutual inductor play roles of the limiting elements. The working principle of the SFCL is analyzed theoretically and the mathematical model of the SFCL is built. Simulation has been carried out by using EMTDC in a 10 kV/1 kA three-phase power system. The simulation show good results. The performance of the SFCL with mutual inductor is validated, and the feasibility of the SFCL with mutual inductor is also demonstrated