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In this work, the genetic algorithm is employed to optimize both circadian action factor (CAF) and color quality of laser-based illuminants (LBIs) with three, four, and five spectral bands to disclose its possible use in two common white lighting applications, i.e. bedroom lighting and office lighting. Comparing all LBIs at a correlated color temperature (CCT) of 3000 K and a color rendering index of 80, the CAF of four-band LBIs reaches a minimum of 0.238 and maintains at a possibly highest luminous efficacy of radiation (LER) of 422 lm/W among all cases. The performances of white LBIs are also compared with those of white light-emitting diodes (LEDs). The results demonstrate that, under the same conditions of color rendering and color temperature, both four-band LBIs and four-band LEDs exhibit the largest circadian tunability of about 4.7, while four-band LBIs possess much higher LER at the same time compared with four-band LEDs. In addition, for the display application, the investigation on the optimal circadian tunability as a function of color gamut at two CCTs (3000 K and 6500 K) is also performed. We believe that this study can serve as a useful guidance for the application of LBIs in both the healthy general lighting and display.

Partial discharge (PD) features analysis and effective PD features selection play an important role in interference signal rejection and PD identification of High Voltage (HV) cables. In the paper, combination PD features analysis of HV cables is presented, in terms of visualization performance of these features, in order to select several effective PD features for interference signal rejection. Firstly, the five types of artificial defect of HV cable and the testing system of PD signals were introduced. The PD testing experiment was carried out. Secondly, based on the raw data obtained from the experiment, the PD signals and interference signals were extracted. Then the feature extraction was carried out, including one-dimensional feature extraction, two-dimensional and three-dimensional feature construction. Finally, the visualization analysis, including one-dimensional feature visualization, two-dimensional feature visualization and three-dimensional feature visualization, was applied to evaluate the combination PD features. Results show that the effective PD features for interference rejection of PD detection are the features related to wavelet features and features which can represent the rise time and fall time of PD pulses.

Recently, graph convolutional neural networks has become a research hotspot for skeleton-based action recognition because of its excellent performance on graph structure data. Compared to traditional methods, it can explicitly exploit the natural connectivity among the joints and improve greater expressive power. In this paper, we propose a two-stream graph convolutional networks with objects for skeleton-based action recognition. An algorithm is designed for matching similar skeleton in adjacent frames, so that we can get the right skeletons which belong to the same person. It performs well when there are other irrelevant persons in the scene. In addition, other features are less employed except for the human joint in skeleton-based action recognition. We introduce limbs orientation information and related objects information. The related objects are treated as joint points which link with hands. The two-stream networks are built to model coordinate features and orientation features respectively, the results of two streams are fused to one. We get good results on the Kinetics dataset with our methods.

Hyperspectral image classification has been widely applied in many fields, but it also faces challenges because of small number of labeled samples. In this paper, we propose the Multiscale Multistage Spectral-Spatial Feature Fusion Framework (M^2 S^2 F^2 ) for hyperspectral image classification using small training samples. The Framework is the combination of two deep convolutional neural networks, which can extract more representative and discriminative features by combining the following operations. Firstly, two different scale 3-D cubes are the inputs for the spectral and spatial feature extraction respectively. Secondly, by fusing strong complementary information between different layers, we form multistage spectral and spatial features by fusion primary, intermediate and advanced features of the spectral and spatial features respectively. Spectral and spatial features are extracted by spectral and spatial skipped residual blocks, which can effectively alleviate the problems of gradient degradation. Thirdly, the fusion of complementary multistage spectral and spatial features can improve the classification accuracy. Experimental results on the IN, UP and KSC datasets show the effectiveness of the proposed method using small training samples.

Human multi-target tracking in video is an important issue in the field of computer vision. It is necessary to detect the target on each frame, and to connect the targets of all frames into a target sequence. For target matching among different frames, we propose a tracking algorithm for constructing object pose sequence(COPS) based on Openpose. The position status and the ORB feature of the target pose are dynamically weighted and fused into new features. Target pose is searched in the corresponding target pose sequence by comparing the new features between the target pose in the sequence and every pose in current frame. When the target pose is matched, the influence of the position feature on the pose similarity could be enhanced when the target motion is continuously detected. When the target scale changes too much, the method can expand the contribution of the ORB feature to the pose similarity comparison. The experiments of human multitarget tracking algorithm are carried out on the PoseTrack and MOT datasets, and the results show that the proposed tracking algorithm overcomes the problem of target matching between frames.

Objective Balloon sinuplasty could restore nasal sinus drainage and airflow, limiting the damages and lowering the risks. This study aimed to assess the 3-year clinical efficacy, safety, and satisfactory degree of balloon sinuplasty through multiple aspects. Also the experience about treatment for postoperative adhesion was described. Materials and methods A study was performed in 30 children who had failed medical therapy, and received Balloon sinuplasty of selected sinuses. Data in 3-year follow-up including questionnaire, VAS, CT, and nasal endoscopy findings were collected. Also postoperative nose-related medications or auxiliary therapies, revision surgery, and incidence of complications were collected. The satisfactory degree of children and parents were assessed. Results Compared to preoperative, the VAS scores, questionnaire (SN-5 or SNOT-22) scores and Lund-Mackay scores were significantly lower. In the 3-year follow-up, most of them did not require nose-related medications or auxiliary therapies, and were free of symptoms, or the symptoms did not affect their daily activities. None of the 30 children had complications of facial pain, teeth numbness, facial deformity, and dysosmia. However, nasal cavity adhesion still remained the most frequent. The satisfactory degree was relatively high. Conclusion The 3-year follow-up demonstrated that balloon sinuplasty had high clinical efficacy and safety, the satisfactory degree of children and parents remained relatively high. Improved the upper respiratory infection and increased the immunity, which were considered effective methods to reduce the risk of recurrence. Nasal spraying of steroids and nasal irrigation in three months after surgery cold help prevent the nasal cavity adhesion.

A new type of retaining wall, the self-balance retaining wall, is introduced in this paper. Based on the stress analysis, the calculation model and method are advanced about the retaining wall. A comparative analysis related to traditional retaining wall is carried out on stress and cost combining with an actual project. The results show that the idea of using upper gravity retaining wall as the resistance of lower retaining wall is clever and reasonable that the self-balance retaining wall has a very wide scope of application relying on the anchor tensile conditions rarely and that the self-balance retaining wall has a great economic value with low cost. The cost of the self-balance retaining wall is 50% compared with the cantilever pile retaining wall under the same conditions which has a good economic effect and application prospect.

CdSe was electrochemically deposited on pure Ti from SeSO3 2- source forming Ti/CdSe Schottky diode with deposition time 113s, 225s and 450s. SEM and current-voltage were employed to study the photo-electronic properties of the Schottky diode. The results show interesting, unexpected phenomena. The current density and the open-circuit voltage of 113s in the dark Ti/CdSe are higher than its analogous devices. Then an interpretation was probably given.

In this paper, 3J-IMM solar cells were studied in comparison with 3J-LM solar cells grown by MOCVD. The structural characteristics were studied by HRXRD, HRTEM and SIMS, which showed a high crystal quality of the metamorphic sub-cell. The solar cell performance in terms of I-V curves and EQE was investigated between the different solar cells structures. The current of the IMM solar cell is almost equal to the LM ´monitor solar cell. Under AM 1.5D, 1000 suns conditions, an Isc of 14.29 A, Voc of 3.538 V, FF of 83.9 %, and an efficiency of 42.3 % were achieved for the 3J-IMM solar cell with a chip size of 1.0 cm2, which is an absolute 2.9% higher than that of a 3J-LM solar cell in conversion efficiency. The excess current contribution from the Ge bottom cell in the 3J-LM solar cells is eliminated, accompanied with a 0.3V increase in Voc for the 3J-IMM solar cells.

Zincblende CrSb (zb-CrSb) layers with room-temperature ferromagnetism have been grown on relaxed and strained (In,Ga)As buffer layers epitaxially prepared on (001) GaAs substrates by molecular-beam epitaxy. The structural characterizations of CrSb layers fabricated under the two cases are studied by using synchrotron grazing incidence x-ray diffraction (GID). The results of GID experiments indicate that no sign of second phase exists in all the zb-CrSb layers. Superconducting quantum interference device measurements demonstrate that the thickness of zb-CrSb layers grown on both relaxed and strained (In,Ga)As buffer layers can be increased to similar to 12 monolayers (similar to 3.6nm), compared to similar to 3 monolayers (similar to 1nm) on GaAs directly.

In recent years, with the development of solar cell technology, the conversion efficiency of the lattice-matched Ga0.51In0.49P/In0.01Ga0.99As/Ge triple-junction solar cell has achieved 30% under AM0 spectrum. As is well known, it is difficult to further improve the efficiency due to the limited bandgap combination. Therefore, an inverted metamorphic triple-junction solar cell is designed by replacing the Ge subcell with a 1.0 eV InGaAs subcell. The efficiency could be increased with the open-circuit voltage increasing, while the short circuit current maintains a similar value.#br#In this paper, the inverted metamorphic GaInP/GaAs/In0.3Ga0.7As triple-junction solar cells are grown on 4-inch GaAs substrates via metal organic chemical vapor deposition. Optimizing the epitaxy process, AlInGaAs graded buffer shows nearly 100% relaxation by the reciprocal space mapping of the high-resolution X-ray diffraction and low average threading dislocation density~5.4×106/cm2 evaluated from the cathodoluminescence image. Finally, the inverted metamorphic triple-junction solar cell with 24 cm2 area shows a conversion efficiency of 32% with an open-circuit voltage of 3.045 V and a short-circuit current of 404.5 mA under one sun, AM0 spectrum, 25℃ conditions, which is 5% higher than the lattice-matched GaInP/InGaAs/Ge triple-junction solar cell. Under 1 MeV electron irradiation test, the degradations of the external quantum efficiency and I-V characteristics of inverted metamorphic triple-junction solar cell are exhibited each as a function of fluence, and finally the end-of-life efficiency is 27.2% with a degradation of 15% under 1×1015/cm2 fluence. More experiments mainly focusing on the lattice quality of AlInGaAs graded buffer and the structure of In0.3Ga0.7As subcell, will be carried out to improve the efficiency and enhance the radiation hardness.

Adopting color-coded structured light Three-dimensional measurement of color target, due to the superposition of two colors, colored stripes on the target color will occur distorted changes, resulting in decoding errors of colored stripes, leading to measurement error. Focus on this problem, we propose a color component information processing method which through regression analysis build a mathematical model based on the relationship of the reflected light and incident light and the surface color, using the least squares method for solving the model, in order to get the relationship of the reflected light and the incident light color component and surface color component, and restore the color of the projected stripes to ensure the correctness of the striped decode. The experimental results show that this method has a good effect on decoding.

For the purpose of constructing advanced mathematics course group for undergraduate economics majors, the thesis discusses the teaching reform that centers on transferring the focus of the advanced mathematics course group of applicationoriented universities from “mathematical calculation” to “application of mathematics”. The thesis covers the reform practiced in different aspects, from curriculum orientation and teaching model to assessment and evaluation system, of the advanced mathematics course group offered to Beijing City University (BCU) undergraduate economics majors. As a trial reform, the practice has achieved good effects.

In this paper a algorithm of level scan-line filling is introduced that can realize contour filling, which is obtained by tracing contour clockwise in 8-adjacent image, we decide the role of current point by judging its in-direction, out-direction and contour extending trend. Through the algorithm can we realize the full-filling of a closed region.

The article presents a new way to apply IP multicast technology in computer laboratory teaching, this system can keep the data transmission in a limited area, so as to increase the efficiency of network.

In order to promote the reliability of network management, a fault tolerant reconstruction mechanism based on distributed agents is proposed. The mechanism provides malfunction reconstruction one for the key nodes in network management, or domains manager, so as to ensure the accomplishment of network tasks from the malfunction of domains manager. This paper puts forward a two-phase fault tolerance reconstruction algorithm with the ability of fault tolerance. Besides, it also gives the formal description of the algorithm and the complex analysis, as well as illustrating the advantage of this algorithm. Moreover, this paper also explains the entity structure of distributed agents.

To meet the requirements of high precision low frequency measurement applications, a 16-bit sigma-delta A/D converter with programmable gain was proposed. The programmable gain input allows the ADC to accept input signals directly from a strain gage or transducer removing a considerable amount of signal conditioning. The circuit could also be digitally programmed to yield four input-to-output gain values (times 1, times 2, times 32, times 128). Since the use of chopper stabilization technique in the delta-sigma converter section, low frequency error reduction was achieved. It was designed in 0.6mum CMOS process and simulation results showed all desired performances were well achieved

We examined genetically determined oxidation polymorphisms of metoprolol and mephenytoin in 200 unrelated, healthy Japanese subjects and in 98 mainland Chinese subjects simultaneously. This examination was done according to the respective reported phenotyping criteria by use of the urinary metabolic ratio of metoprolol and of the percentage of excretion of 4-hydroxymephenytoin 8 hours after dose administration. The frequencies of occurrence of poor metabolizers (PMs) in the Japanese versus the Chinese subjects were 0.5% versus 0% for metoprolol and 22.5% versus 17.4% for mephenytoin, respectively. There were no statistically significant differences in these frequencies between the two Oriental populations. However, Chinese extensive metabolizers (EMs) showed a significantly lower excretion of alpha-hydroxymetoprolol (p less than 0.01) and 4-hydroxymephenytoin (p less than 0.001) than that of Japanese EMs, and the mode of the distribution histogram of the Chinese EMs for the two test probes was skewed compared with that of the Japanese EMs. The findings indicate that the two Far Eastern Oriental subject groups have a lower frequency of PM phenotype of debrisoquin/sparteine-type oxidation and a greater incidence of PM phenotype of mephenytoin oxidation compared with the respective frequencies reported from white subjects. However, the explanation for the observation that the metabolic capacities of the test drugs differed between the EMs of the two populations who had a similar ethnic origin and who resided in the same geographic area remains obscure.