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The ground penetrating radar (GPR) data in the complex detection environment is non-stationary, non-Gaussian, and non-uniform, so the traditional noise attenuation methods are difficult to meet the requirements of denoising. Therefore, we introduced the K-singular value decomposition (K-SVD) dictionary learning into the denoising of GPR signals. It uses the orthogonal matching pursuit (OMP) algorithm to sparse decompose different radar data and trains the overcomplete dictionary with sample characteristics. K-SVD makes full use of the prior information and can extract features according to the sample data adaptively, which means it has strong sparse representation competence. Because radar signals can be sparsely represented in the dictionary, whereas the random noise does not have a sparse representation, the K-SVD dictionary can be used to distinguish effective signals from noise in the GPR data. We used the discrete cosine transform (DCT) and K-SVD dictionaries to process the Gaussian noise and stochastic clutter in the GPR profile. The results show that both K-SVD and DCT can effectively suppress the Gaussian noise. But for the clutter generated by the random medium, the DCT dictionary also causes damage to the effective signals while removing the noise; whereas the K-SVD dictionary learning algorithm uses the DCT dictionary as the initial dictionary and carries out adaptive learning on the noisy data, considering the information in the block and the global observation to complete the denoising, with good denoising effect and high fidelity. We finally verified the effectiveness and practicability of the K-SVD method for measured data.

In the atmosphere, cloud particles have different shapes. The study of cloud particle shapes plays an important role in understanding cloud precipitation processes, radiative transfer, and weather ...

The genetic diversity of germplasm is critical for exploring genetic and phenotypic resources and has important implications for crop-breeding sustainability and improvement. However, little is known about the factors that shape and maintain genetic diversity. Here, we assembled a high-quality chromosome-level reference of the Chinese common apricot ‘Yinxiangbai’, and we resequenced 180 apricot accessions that cover four major ecogeographical groups in China and other accessions from occidental countries. We concluded that Chinese-cultivated common apricot germplasms possessed much higher genetic diversity than those cultivated in Western countries. We also detected seven migration events among different apricot groups, where 27% of the genome was identified as being introgressed. Remarkably, we demonstrated that these introgressed regions drove the current high level of germplasm diversity in Chinese-cultivated common apricots by introducing different genes related to distinct phenotypes from different cultivated groups. Our results highlight the consideration that introgressed regions may provide an important reservoir of genetic resources that can be used to sustain modern breeding programs.

Cloud particles have different shapes in the atmosphere. Research on cloud particle shapes plays an important role in analyzing the growth of ice crystals and the cloud microphysics. To achieve an accurate and efficient classification algorithm on ice crystal images, this study uses image-based morphological processing and principal component analysis, to extract features of images and apply intelligent classification algorithms for the Cloud Particle Imager (CPI). Currently, there are mainly two types of ice-crystal classification methods: one is the mode parameterization scheme, and the other is the artificial intelligence model. Combined with data feature extraction, the dataset was tested on ten types of classifiers, and the highest average accuracy was 99.07%. The fastest processing speed of the real-time data processing test was 2,000 images/s. In actual application, the algorithm should consider the processing speed, because the images are in the order of millions. Therefore, a support vector machine (SVM) classifier was used in this study. The SVM-based optimization algorithm can classify ice crystals into nine classes with an average accuracy of 95%, blurred frame accuracy of 100%, with a processing speed of 2,000 images/s. This method has a relatively high accuracy and faster classification processing speed than the classic neural network model. The new method could be also applied in physical parameter analysis of cloud microphysics.

With the progress of the times, the development of science and technology, the deepening of research in various fields, and the accuracy requirements for DEM are becoming higher and higher, and the DEM of satellite image interpretation has become more and more unable to meet the needs of research. UAV photogrammetry, as a new aerial survey and monitoring method, has the characteristics of high precision, low cost and fast renewal, which can make up for the shortcomings of traditional means in topographic survey. This paper takes the Wuyiling Nature Reserve as the research object, uses the UAV photogrammetry technology combined with the improved progressive triangular mesh filtering algorithm to extract the DEM, obtains the resolution 0.5 m terrain data, and evaluates it. The result verification shows that the precision DEM constructed by progressive triangulation encryption filtering based on region segmentation can display the terrain information more intensively; especially for high-vegetation area, high-resolution DEM can be generated to reflect the real surface condition.

In this paper, a temperature thermostat used for the hydrogen maser is designed and fabricated based on the analysis of heat dissipation of the hydrogen maser. The high power and precise temperature control is realized by using the PID temperature control and semiconductor refrigeration techniques in the design and fabrication of thermostat. Under the condition of 300 W heat dissipation, the temperature fluctuation is within ±0.05 ℃, better than the existing similar products in the worldwide. The thermostat could provide excellent temperature environment for a high performance hydrogen maser.

Background: Air pollution has been suggested as a risk factor for chronic obstructive pulmonary disease (COPD), but evidence is sparse and inconsistent. Objectives: We examined the association between long-term exposure to low-level air pollution and COPD incidence. Methods: Within the ‘Effects of Low-Level Air Pollution: A Study in Europe’ (ELAPSE) study, we pooled data from three cohorts, from Denmark and Sweden, with information on COPD hospital discharge diagnoses. Hybrid land use regression models were used to estimate annual mean concentrations of particulate matter with a diameter < 2.5 µm (PM2.5), nitrogen dioxide (NO2), and black carbon (BC) in 2010 at participants’ baseline residential addresses, which were analysed in relation to COPD incidence using Cox proportional hazards models. Results: Of 98,058 participants, 4,928 developed COPD during 16.6 years mean follow-up. The adjusted hazard ratios (HRs) and 95% confidence intervals for associations with COPD incidence were 1.17 (1.06, 1.29) per 5 µg/m3 for PM2.5, 1.11 (1.06, 1.16) per 10 µg/m3 for NO2, and 1.11 (1.06, 1.15) per 0.5 10−5m−1 for BC. Associations persisted in subset participants with PM2.5 or NO2 levels below current EU and US limit values and WHO guidelines, with no evidence for a threshold. HRs for NO2 and BC remained unchanged in two-pollutant models with PM2.5, whereas the HR for PM2.5 was attenuated to unity with NO2 or BC. Conclusions: Long-term exposure to low-level air pollution is associated with the development of COPD, even below current EU and US limit values and possibly WHO guidelines. Traffic-related pollutants NO2 and BC may be the most relevant.

With the rapid development of artificial intelligence, the technology has penetrated deeply into the core areas of high-level education. Higher vocational colleges should help the existing artificial intelligence technology to cultivate more outstanding talents, completely change the traditional teaching mode, make the teaching more scientific, lively and interesting. It should gradually cultivate the ability of students to learn independently, and improve the comprehensive ability, and constantly strengthen the speed and efficiency of basic teaching.

Gastric Antrum (GA) cross-sectional area measurement using ultrasound imaging is an important point-of-care (POC) application in intense care unit (ICU) and anesthesia. GA in ultrasound images often show substantial differences in both shape and texture among subjects, leading to a challenging task of automated segmentation. To the best of our knowledge, no work has been published for this task. Meanwhile, dice similarity coefficient (DSC) based loss function has been widely used by CNN-based segmentation methods. Simply calculating mask overlap, DSC is often biased towards shape and lack of generalization ability for cases with diversified and complicated texture patterns. In this paper, we present a robust segmentation method (TexNet) by introducing a new loss function based on multiscale information of local boundary texture. The new texture loss provides a complementary measure of texture-wise accuracy in contour area which can reduce overfitting issues caused by using DSC loss alone. Experiments have been performed on 8487 images from 121 patients. Results show that TexNet outperforms state of the art methods with higher accuracy and better consistency. Besides GA, the proposed method could potentially be an ideal solution to segment other organs with large variation in both shape and texture among subjects.

Enhancing sensitivity of carcinoma to sorafenib (Sor) is critical to overcome the limits of high frequency resistance and moderate efficiency during chemotherapy for advanced hepatocellular carcinoma (HCC). Here, we promote sensitivity of HCC to Sor by combination with Artesunate (Art), a derivative of artemisinin extracted from Chinese medical herb. The positive synergy of Art on inhibiting HCC growth contributes 48% dosage of Sor to reduce tumor cell viability in vitro and tumor size in vivo. Mechanically, in spite of effective suppression of RAF/MEK/ERK pathway, Sor is not able to eliminate chemoresistance of HCC driven by PI3K/AKT/mTOR pathway, while Art inhibits phosphorylation of AKT and mTOR significantly. Furthermore, combination with Art and Sor further improves apoptosis of HCC by dual inhibition of both pathways. Our study reveals a function of Art that induces HCC apoptosis via PI3K/AKT/mTOR pathway inhibition and suggests a potential therapeutic regimen of combination with Art and SOR against advanced HCC.

The traditional feature extraction method for pattern recognition increases the computational complexity of the recognition method due to the excessive feature extraction, which leads to the low accuracy of the recognition method. To solve the above problems, a fingerprint feature extraction pattern recognition method based on random game is proposed for mobile APP. After the fingerprint image processing, the fingerprint features in the image are extracted. After removing the pseudo-feature points from the extracted image features, the pattern recognition of fingerprint features is completed by using the stochastic game theory. Through the simulation experiment, it is verified that the recognition accuracy of the proposed method increases by about 1/5, and has better recognition stability.

This study retrofitted the rich-split carbon capture process by introducing a commercial multi-channel ceramic membrane heat exchanger (Multi-CMHE) for waste heat recovery from the stripped gas vented from the CO2 stripper. The parametric study and economic analysis were conducted to comprehensively evaluate the feasibility, adaptability, and net profit of Multi-CMHE-modified rich-split monoethanolamine-based carbon capture process. Results showed that a large pore-sized Multi-CMHE has a low mass transfer flux but a high heat transfer flux. An increase in the bypassed CO2-rich solvent flow rate, water vapor molar fraction in the stripped gas and total gas pressure in addition to a decrease in the CO2-rich solvent temperature can greatly enhance the heat recovery performance. The maximum specific heat recovery can reach up to 1423.3 kJ/kg-CO2 for the 30 nm pore-sized Multi-CMHE. Furthermore, an economic analysis of the Multi-CMHE-modified rich-split carbon capture process was conducted based on the maximum stripped gas treatment amount at a fixed membrane area. Technical and economic feasibilities of the Multi-CMHE modification were thus confirmed. The maximum net profit reaches to USD$ 2.73/t-CO2 when the regeneration heat saving is 900 kJ/kg-CO2. Sensitivity analyses indicated that this modified process is preferred in a high fuel price scenario. Additionally, the further membrane innovation should be oriented to improve the heat recovery performance and maximize the net profit in the future.

BACKGROUND: Adverse cardiovascular effects associated with air pollution exposure have been widely demonstrated. However, inconsistent cardiovascular responses were observed from reducing indoor air pollution exposure. We aimed to assess whether short-term air filtration intervention could benefit cardiovascular health in elderly living in high pollution area. METHODS: A randomized crossover intervention study of short-term indoor air filtration intervention on cardiovascular health was conducted among 35 non-smoking elderly participants living in Beijing in the winter of 2013, as part of Beijing Indoor Air Purifier StudY (BIAPSY). Portable air filtration units were randomly allocated to active filtration for 2 weeks and sham filtration for 2 weeks in the households. Twelve-hour daytime ambulatory heart rate variability (HRV) and blood pressure (ABP) were measured during active and sham filtration. Concurrently, real-time indoor and outdoor particulate matter with diameter less than 2.5 µm (PM2.5) and indoor black carbon (BC) concentrations were measured. We applied generalized additive mixed models to evaluate the associations of 1- to 10-h moving average (MA) exposures of indoor PM2.5 and BC with HRV and ABP indices, and to explore whether these associations could be modified by air filtration. RESULTS: We observed decreases of 34.8% in indoor PM2.5 and 35.3% in indoor BC concentrations during active filtration. Indoor PM2.5 and BC exposures were significantly associated with reduced HRV and increased ABP indices, and greater changes were observed during sham filtration. In specific, each 10 μg/m3 increase in indoor PM2.5 at MA8-h was associated with a significant reduction of 1.34% (95% CI: -2.42, -0.26) in SDNN during sham filtration, compared with a non-significant reduction of 0.81% (95% CI: -6.00, 4.68) during active filtration (Pinter

Background Oily skin is one of the most common dermatological complaints. Oily skin may be accompanied by enlarged pores, acne, and seborrheic dermatitis. Moreover, oily skin has negative effects on self-perception. Most therapeutic approaches used to treat oily skin have had varying degrees of efficacy and include topical treatments, such as photodynamic therapy and lasers. However, certain of these therapies for oily skin may lead to severe side effects. With the expanding use and high safety profile of botulinum toxin type A (BoNT-A), its use in the treatment of oily skin has caused significant concerns; moreover, relevant reports have gradually accumulated to address the efficacy of BoNT-A and explore its mechanisms of action. Aims The objective of this article was to review the efficacy and possible treatment mechanisms of BoNT-A on oily skin. Methods A retrospective review of the published data was conducted. Results Most studies have suggested that the intradermal injection of BoNT-A decreased sebum production and pore size. Furthermore, this treatment attained high patient satisfaction without significant side effects. BoNT-A effectively decreased sebum production and excretion, which was in keeping with previous studies, possibly via its blockade of cholinergic signaling and its neuromodulatory effects. Conclusions Intradermal BoNT-A injection may represent a promising new treatment for oily skin and other relevant dermatological problems, such as enlarged pores, acne, and seborrheic dermatitis. Further study is still needed to determine the specific mechanisms of BoNT-A and the optimal injection techniques and doses for oily skin and other relevant cosmetic concerns.

Because the vibration signal data has a high dimension, ordinary fault prediction methods are very complicated for data preprocessing. A fault diagnosis method combining DBN and LSTM was proposed in this paper. This method uses DBN's excellent feature extraction capability to extract feature vectors of time-series fault data, and uses LSTM network to perform fault prediction on the extracted feature vectors, because LSTM network has good adaptability to sequential data. The author used the bearing data of Case Western Reserve University to build a training set and conduct experiments. Experimental results show that this method can reduce the difficulty of data preprocessing and increase the accuracy of fault prediction.

A dual-band variable gain amplifier operating at 0.9GHz and 2.4GHz was designed based on high performance RF SiGe HBT for large amount of signals transmission and analysis. Current steering was adopted in gain-control circuit to get variable trans-conductance and then variable gain. Emitter degeneration and current reuse were considered in amplifying stage for low noise figure and low power dissipation respectively. A single-path circuit resonating at two frequency points simultaneously was designed for input impedance matching. PCB layout parasitic effects, especially the via parasitic inductor, were analyzed theoretically and experimentally and accounted for using electro-magnetic (EM) simulation. The measurement results show that a dynamic gain control of 26dB/16dB in a control voltage range of 0.0-1.4V has been achieved at 0.9/2.4GHz respectively. Both S11 and S22 are below than -10dB in all the control voltage range. Noise figures at both 0.9GHz and 2.4GHz are lower than 5dB. Total power dissipation of the dual-band VGA is about 16.5mW at 3V supply.

With the performance improvement of satellite payload, satellite payload data simulators with high-speed and large-capacity are eagerly demanded by ground automatic test system for the testing of satellite data transmission system. Based on the analysis of traditional simulators, a new design with FlexRIO is introduced in this paper. Based on the PXIe architecture, the simulator mainly consists of data source module and data loading module. In-chassis high-speed data storage board is used as the data source module, which achieves a storage capacity of 2.9TB and is easy to extend. The data loading module is composed of FlexRIO and its adapter, of which the single-channel serial transmission rate is up to 1.2Gbps with TLK2711A as the transmission interface chip. And six channels are supported to work at the same time. Test results show that with high reliability and strong versatility, the simulator has no bit-error in laboratory. Hence, the payload data simulator can be used for satellite test directly, and can provide reference for the design of other high-speed data loaders.

In the cloud computing environment, how to schedule tasks efficiently according to users' service requirements and improve the quality of service have become a hot research topic. Based on the research of independent task scheduling model and AMM algorithm (Average Minus Minimum), a new PAW(Priority, AMM and Weight)algorithm combined with Priority, AMM and Weight is proposed. Through quantifying task priorities and execution effect on each node, PAW solves many remaining problems in other algorithms, such as long waiting time of urgent tasks, low qualities of services and so on. CloudSim, a cloud computing simulator is used as a tool to analyze PAW algorithm, and the simulation results show that PAW algorithm has good effects on priority processing, load balancing and makespan. This demonstrates that the proposed algorithm is an effective task scheduling method in cloud computing environment.

In this paper, the equivalent circuit model of UTC-HPT is established to simplify the microwave optical amplifier and mixer design. Based on the equivalent circuit model of HBTs, the photo-generated current in UTC-HPT is introduced reasonably as part of base current. The influence of photogenerated carriers on several equivalent circuit components such as trans-conductance, barrier capacitor, diffusion capacitor and junction resistor are considered carefully in the model. Finally, the collector output current is checked to verify the model validity and the photo-current gain and the photo-characteristic frequency are analyzed with the established model.

The uncertainty of driving area, the power load control of charging facility and charging rates make electric vehicles(EVs) facing different charging facilities, so it is necessary to control charging in the charging process. An adaptive electric vehicle charging control strategy was proposed in this paper. The strategy uses wifi for communication, communicating with charging pile through wifi, charging facilities and electric vehicles can exchange parameters to achieve adaptive control of the charging process. And experiment was conducted for verification.

A low power variable gain wideband low noise amplifier (LPVG-LNA) was designed in this paper by using active inductor and multiple current reuse circuit structures. At the input stage of LPVG-LNA, a noise canceling structure and an active inductor were employed to reduce noise figure and to realize input matching and gain tuning respectively. At the middle stage, three common-emitter amplifier was utilized to realize high gain. Furthermore, current reuse technique is used at input stage and middle stage respectively to reduce power consumption. At the output stage, an emitter follower was adopted to achieve output matching. Based on WIN 002μm GaAs HBT technology, the proposed LPVG-LNA was verified. The results show that in the frequency range of 1–3GHz, the LPVG-LNA has the gain (S 21 ) of over 37.56dB, the maximum gain tuning range of 4.22dB, the input return loss (S 11 ) of less than −7.06dB, the output return loss (S 22 ) of less than −18.52dB, the noise figure (NF) of less than 4.6dB, the stability factor (k) of over 10.68. The static power dissipation of the LPVG-LNA is less than 35mW under the operation voltage of 5V.

In this paper, the optical gain characteristics and optical high frequency characteristics of an InP-based uni-traveling-carrier double heterojunction phototransistor (UTC-DHPT) are illustrated. The detailed analysis of UTC effects on those perfomaces show that UTC transport mechanism successfully weaks the space charge effect in the collector junction and breaks the limitation of low mobility of the holes. Compared with traditional single heterojunction phototransistor (SHPT), UTC-DHPT improves its processing ability of high power optical signal and provides high saturation current, high responsivity and high response speed simultaneously.

A novel kind of As 2 Se 3 chalcogenide glass multi-ring photonic crystal fiber is proposed. The characteristics of multi-ring photonic crystal fiber have been studied by the finite element method. Compared with another two kinds of single-core photonic crystal fibers, the multi-ring PCF can make the perfect combination of the effective mode area, the nonlinearity coefficient and multi-zero dispersion. It can achieve high power supercontinuum generation in middle infrared band; It also can be used in high-power pulsed laser fiber amplifier and high-power ultra-short pulse laser transmission in far infrared band.

A novel kind of polarization splitter based on tellurite glass dual-core photonic crystal fiber is proposed. The characteristics of the polarization splitter have been studied by the finite element method. By adjusting the ellipticity of the dual-core PCF, a very high value of birefringence can be reached. The high birefringence can increase the D-value of coupling length in the two orthogonal polarization directions, then the polarization-independent splitter can be achieved. Comparing with the SF57 glass dual-core PCF, the tellurite glass dual-core PCF has higher extinction ratio, the extinction ratio can reach −31 dB at the wavelength λ = 1.55 μ m . The 0.36-mm-long splitter is proposed to achieve extinction ratio better than −10 dB and a bandwidth of 20 nm.

This paper proposes an analysis of the vector-controlled induction-motor (IM) drive with a novel modelreference adaptive system (MRAS)-type rotor speed estimator .In this scheme which stator-current-error-based MRAS is used instead of the rotor-flux-error-based MRAS scheme,an stator-current-error-based MRAS is used for estimate the IM rotor speed ,and this is used as feedback signals for the indirect field oriented control technique (IFOC),which is a widely used control method for Induction Motor drive (IM). For improving the dynamic characteristic of the system, it is very improtant for vector control to proceed parameter tuning.Some experimental results based on TMS 320F2812 DSP are provided to verify the proposed system performance in a low speed at no-load and load conditions.

Optical fiber devices and applications in the 2-μm band have been investigated extensively due to its unique advantages, such as eye safety. A fiber sensor based on tilted fiber Bragg grating with a grating plane angle of 2 deg is fabricated and experimentally tested. To the best of the authors’ knowledge, this is the first tilted fiber Bragg grating sensor to realize simultaneous measurements of temperature, axial strain, and a certain range of surrounding refractive index (SRI) at the 2-μm band. This paper uses the wavelength detection method and selects three independent resonant wavelengths as the investigated parameters. Results show that perturbations of temperature, axial strain, and SRI can shift the wavelengths of the core mode resonance and cladding mode resonance to some degree. The temperature sensitivities of the core mode and cladding mode are nearly the same, but their axial-strain sensitivities are different. Furthermore, the core mode is insensitive to the change in SRI. The sensitivities of SRI, temperature, and strain can thus be obtained by experimentally determining the wavelength shifts of the three independent resonance peaks. A 3 × 3 matrix containing the relationship coefficients between the disturbances of temperature, axial strain, and SRI and wavelength shifts is constructed. By reversely solving the matrix equation, variations in temperature, strain, and SRI can be obtained using the experimental determination of wavelength drifts.

International audience; Se with good glass formation ability was gradually doped into the Ge-As-Te glasses, and then the gradual change processes of some key physical and optical properties were observed. A series of Ge10As40Te50-xSex(x=0, 10, 20, 30, 40, 50) chalcogenide glass samples were prepared by the traditional melt-quenching method. The internal microstructure, physical and chemical properties of the glass samples were analyzed by using X-ray diffraction, Raman spectroscopy and thermal dilatometer instruments. Vis-NIR absorption spectra and infrared optical transmission spectra of these glasses were recorded with Spectrophotometer and Fourier transform infrared spectroscopy instrument. Then, the Tauc equation was adopted to calculate the direct and indirect optical band gaps of the glass samples. The results show that with the increasing of the Se, the thermal stability can be effectively improved, the maximum Tg can reach up to 233℃. A obvious blue shift of short infrared absorption spectrum cut-off edge appearance is observed in these glasses, i.e. The optical band gap increases gradually, which shows a wider range of transmission and better transparency spectrum, the maximum transmission rate can reach up to 56%. Infrared cut-off edge remains at 20μm, while Se content is less than 2 mol, its thermal stability is improved obviously and the optical spectral changes little. At last, using metal Mg as an oxide redactor for the purification of these glasses, the results show that the transmission spectra is much smooth and without any obvious impurity absorption peaks after the appropriate purification process. © 2016, Science Press. All right reserved.

The use of wireless sensor networks for indoor localization application has emerged as a significant area of interest over the last decade, primarily motivated by its low cost and convenient deployment. The weighted centroid localization algorithm is a suitable positioning technique in a wireless sensor network due to its easy implementation. However, the performance of this method is easily affected by outliers and interference in the measurement of radio signal strength. In order to overcome this limitation, a more robust ARMA filter using generalized t-distribution noise model based on influence function approach is proposed. A hardware prototype was implemented to demonstrate that the ARMA filter could improve system performance, especially when dealing with the case of measurement outliers.

Based on forced vibration tests for high-performance concrete (HPC), the influence of bridge vibration induced by traveling vehicle on compressive strength and durability of HPC has been studied. It is concluded that 1 d and 2 d compressive strength of HPC decreased significantly, and the maximum reduction rate is 9.1%, while 28 d compressive strength of HPC had a slight lower with a 3% maximal drop under the action of two simple harmonic vibrations with 2 Hz, 3 mm amplitude, and 4 Hz, 3 mm amplitude. Moreover, the vibration had a slight effect on the compressive strength of HPC when the simple harmonic vibration had 4 Hz and 1 mm amplitude; it is indicated that the amplitude exerts a more prominent influence on the earlier compressive strength with the comparison of the frequency. In addition, the impact of simple harmonic vibration on durability of HPC can be ignored; this shows the self-healing function of concrete resulting from later hydration reaction. Thus, the research achievements mentioned above can contribute to learning the laws by which bridge vibration affects the properties of concrete and provide technical support for the design and construction of the bridge deck pavement maintenance.

Optimization of coal transportation has various means, in this paper we established a Storage and Distribution Center(SDC), and compared the coal transport network efficiency before and after setting up a SDC by network optimization ,finding the SDC can increase the value of coal and reduce transportation costs, make the coal supply chain more efficiency and stability, ensure national economic security and the security of coal’s provision. At last, we give an illustrative example to verifie.

This paper develops a new real-time single object tracking system under camera rotation freely. Optical-flow and color information are combined and it proposes a simple and feasible method by updating the feature point to update the template. By capturing the corner and combining with pyramid-optical-flow the problem of real-time tracking in optical-flow is solved. The rotation and tracking under partial occlusion are settled through introducing the color probability distribution and recapturing the feature points. It is proved by experiment that this system is insensitive to the environment and shows a good performance.

Presently, with the rapid increase of China's electricity demand, fluctuation of power load as well as the continuous rise in coal prices, the electricity market generation side of some part region of China is facing risk. By the introduction of BP (Back Propagation) neural network theory, this paper established the regional power generation forecasting model, coal supply, policy implications, weather conditions, resources as well as competitive environment are quantified, then it was used as the network input as well as historical data of the regional power generation to forecast regional power generation as network output, calculate and analysis using by the established model. The outcome shows that this prediction was of full consideration of various factors and adjustment of the relationship between impact factors, it has the merits of minor error and high precision, and it is an effective method of regional power generation prediction.

The transmission spectrum characteristic of two-segment polarization maintaining fibers Sagnac interferometer was investigated and simulated in detail and the optimal parameters for eliminating the crosstalk between the two polarization maintaining fibers was obtained. A temperature-insensitive pressure sensing technology was proposed. An experimental Sagnac interferometer was built and the solid core polarization maintaining photonic crystal fibers were taken as the sensing probe. The side pressure sensitive coefficients and the temperature crosstalk drift were measured and compared. The experimental results show that the side pressure sensitive coefficient was about 0.287 7 nm/N and the temperature drift was less than 0.1 pm/℃.

The rate of photo-electro-chemical (PEC) etching on N-polar n-GaN using vertical light emitting diodes (V-LEDs) has been investigated in detail, by varying the etching parameters (etchant concentration, etching duration and light intensity). V-LED with optimal hexagonal pyramid structure (the side-wall angle is 31°) has been fabricated, and then the influence of the PEC etching on the electrical and optical properties of V-LED has been analyzed. After PEC etching, the sample has good ohmic contact with the electrode and has lower contact resistance than a reference sample. The electrical characteristics have a better improvement. And the light output power has improved obviously after PEC etching, which shows 86.1% enhancement at 20 mA. Effect of side-wall angle of the pyramids on light extraction efficiency (LEE) in V-LEDs is theoretically calculated by finite difference time domain (FDTD) method. Simulation results show that the LEE is significantly increased for the sidewall angle between 20° and 40°, and the maximum enhancement is realized at a side-wall angle of 23.6° (the total reflection angle at the GaN/air interface).

Residual stress conditions in GaN-based LEDs will have a significant influence on device performance and reliability. In this paper, GaN-based vertical LEDs under different stress conditions are fabricated by bonding with three types of submounts (Al2O3 submount, CuW submount and Si submount), changing the soak temperature (290 ℃, 320 ℃, 350 ℃ and 380 ℃) and using different laser energy densities (875, 945 and 1015 mJ·cm-2). The warpage and Raman scattering spectra of those GaN-based LEDs are measured. The experimental results show that the residual stress conditions in GaN-based vertical LEDs are a consequence of the bonded submounts and bonded metal, and the soak temperature is the primary factor that determines the degree of residual stress in LED chips. In the laser lift-off process, changing laser energy density in an appropriate range has little influence on residual strain of LED chips, and the micro-cracks in GaN layer caused by LLO process will play a role in releasing the residual stress. The warpage of epitaxial sapphire substrate becomes large after boding with Si submount, the residual stress in GaN-based vertical LEDs is tensile stress and becomes larger with the soak temperature rising. When GaN epi wafer bonds with Al2O3 submount and CuW submount, the warpages becomes small and large respectively and the residual stress in chips is compressive stress. Because of the mismatch of coefficient of thermal expansion, the compressive stress in GaN-based LED chips increases for Al2O3 submount and drops for CuW submount with the soak temperature rising.