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The echo signal of light detection and ranging (LiDAR) system is easily disturbed by various noises under the influence of intense background light. The signal to noise ratio (SNR) decreases with increasing distance, which seriously affects the retrieval accuracy of the LiDAR system. This paper combines local mean decomposition and an improved thresholding method (LMD-ITM) to process the Lidar signal with a lot of noise, so as to avoid the loss of useful information. In this research, the correlation coefficient and energy entropy are used to distinguish between the relevant and irrelevant components decomposed by the local mean decomposition. Subsequently, the improved thresholding method is applied to process the irrelevant components. It can extract the effective signals which are difficult to be separated from the high-frequency signals. Finally, all components are reconstructed to get the denoising signal. The experimental results demonstrate that this method can effectively avoid the short-range migration, suppress the long-range noise, and adapt to different weather conditions. Compared with the previous denoising method, the proposed method increases the SNR by about 15%.

Ting Qiu,1 Hui Wen,2 Zhen-Xing Liu,2 Xiao-Ping Pan,2 Tao Zeng2 1Department of Obstetrics and Gynecology, Guangzhou Women and Children’s Medical Center, Guangzhou, Guangdong, People’s Republic of China; 2Department of Neurology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong, People’s Republic of ChinaCorrespondence: Tao ZengDepartment of Neurology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, No. 1 of Panfu Road, Guangzhou, 510180, People’s Republic of ChinaTel +86 20 8104 8631Email zeng_tao518@163.comObjective: The present study aims to assess the cognitive function of healthy full-term puerperae and compare it with the cognitive function of healthy non-pregnant women in order to analyze possible influencing factors.Methods: The study subjects were divided into two groups: the maternal (case) group (n = 80) and the control group (n = 30). A total of 50 healthy single-birth full-term primiparous women and 30 women undergoing a second pregnancy were assigned to the maternal group, while 30 non-pregnant women matched by general data were assigned to the control group. Subject cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) (Beijing version) and the Birmingham Cognitive Screen (BCoS) (Mandarin version); related influencing factors were analyzed.Results: In the maternal group, the results showed a MoCA score of 26.52 ± 2.13 points and a cognitive impairment incidence of 26% in primiparous women, along with a MoCA score of 25.83 ± 2.49 points and a cognitive impairment incidence of 36.7% in women undergoing a second pregnancy. All scores were lower in the maternal group than in the control group, which had a MoCA score of 27.47 ± 1.28 points and cognitive impairment incidence of 6.7% (p < 0.05). The differences in MoCA score and cognitive impairment incidence between the primiparous sub-group and the second pregnancy sub-group were not statistically significant (p > 0.05). The visual space and executive function MoCA scale scores were lower in the maternal group than in the control group (p < 0.01). Furthermore, the scores were lower in the maternal group than in the control group in the following BCoS items: instant story recall, total apple deletion number, auditory attention, rule conversion, and gesture imitation (p < 0.05).Conclusion: Women in the postpartum period may develop cognitive dysfunction; however, the difference in cognitive impairment incidence between the primiparous sub-group and the second pregnancy sub-group in this study was not statistically significant. The educational level, labor analgesia, and total labor time (min) were found to be influencing factors in the postpartum cognitive function decline (p < 0.05).Keywords: parturient, cognition, impact, screening, analgesia

In this study, we reported on the construction of p–n junctions based on crystalline Ga-doped CdS–polycrystalline ZnTe nanostructures (NSs) for optoelectronic device application. The coaxial nano-heterojunction was fabricated by a two-step growth method. It is found that the absorption edge of CdS:Ga–ZnTe:Sb core–shell NSs red shifted to about 580 nm, compared with CdS nanowires (520 nm). The as-fabricated core–shell p–n junction exhibited obvious rectification characteristics with a low turn-on voltage of ∼0.25 V. What is more, it showed stable and repeatable photoresponse to 638 nm light illumination, with a responsivity and a detectivity of 1.55 × 103 A W−1 and 8.7 × 1013 cm Hz1/2 W−1, respectively, much higher than other photodetectors with similar device configurations. The generality of this study suggests that the present coaxial CdS:Ga–ZnTe:Sb core–shell nano-heterojunction will have great potential applications in future nano-optoelectronic devices.

Analysis the common gear fault signal, using continuous wavelet transform well time-frequency characteristics and failure mechanism gear features, combined with quasi-periodic signal rotary mechanical characteristics of the continuous wavelet transform fault signal. This method can reduce the noise source and other incentives interference, remove the specific needs of the signal to improve signal stripping effect, the use of a certain type of gear failures this step, to get a clear diagnosis results show that this method has proven a strong application space.

This paper analyzed the kinematical and mechanical feature of the trip operation for the 03A driller based on the dynamic brake theory of AC variable frequency motor. The moving pattern of the strip operation and the variable information of the load in winch roller were mastered. We checked the safety coefficient of the winch brake and put forward the suggestions on the safe operation for AC variable frequency controlled driller. This paper is very important for promoting the application of AC frequency technology in drillers.

The occurrence of volatile arsenic in natural gas, could lead to the poisoning of catalyst in processing equipment, and pose a serious threat to human health. In order to detect the total volatile arsenic in natural gas, this paper analyzed the characteristic and original mechanism of the volatile arsenic first, then a novel method was carried out by using silver nitrate solution, saturated potassium persulfate solution and concentrated nitric acid solution as sorption solution, followed by volatile arsenic determination with ICP-MS .The result showed that 2% silver nitrate solution had a good adsorption effect to volatile arsenic, and the recoveries of arsenic ranged from 87%~103%, which basically met the demand for the rapid detection of volatile arsenic in natural gas.

In order to select the optimal location points for automated drilling and riveting process, an optimization method selecting the location points of Aircraft’s Wing Panel in Automatic Drilling and Riveting System is presented. This method includes three steps: 1) building the matching model based on the multiplicity; 2) presenting the matching method based on scatter search algorithm; 3) selecting the optimal location points according to the minimal deviation based on linear programming method. This method was applied in a panel to match the mathematical surface and the fitting one of this panel perfectly and select the optimal location points. The efficacy and quality during the process of drilling and riveting of this panel was improved greatly.

A new electron trapping materials (ETM) SrS: Eu2+, Dy3+, which was prepared by the method of high temperature solid-state reaction. The results indicate that both ultraviolet light and visible light can be used as exciting source to store energy. After exposed under ultraviolet, the sample was stimulated by 980nm laser. As a result, an obvious luminescence at 615 nm was detected. The up-conversion emission spectrum was found to be a continuous broadband spectrum resulted from the multi-transitions of Eu2+ 4f6→4f7 (8S7/2). The emission peak intensity of SrS: Eu2+, Dy3+ was stronger than SrS: Eu2+.

A model is developed to study the ionospheric ion flux distribution along magnetic force lines in Martian magnetosphere and the influence of Martian intrinsic moment on the distribution. It is discovered that the intrinsic moment has significant influence on the O + ion flux distribution that a lower flux in the magnetotail will be associated with a stronger intrinsic moment. According to the theoretical result and the observed data on the ion flux which is about 7.6×10 6 cm −2 s −1 in the Martian magnetotail, the deduced Martian moment is about 2×10 21 G cm 3 . This agrees well with the most recent data obtained by MAG/ER on the Mars Global Surveyor spacecraft.

In this study, we report a localized surface plasmon resonance (LSPR) enhanced optoelectronic device based on a ZnSe:Sb nanoribbon (NR)/Si nano-heterojunction. We experimentally demonstrated that the LSPR peaks of plasmonic Ag nanoparticles (Ag NPs) can be readily tuned by changing their size distribution. Optical analysis reveals that the absorption of ZnSe:Sb NRs was increased after the decoration of the Ag NPs with strong LSPR. Further analysis of the optoelectronic device confirmed the device performance can be promoted: for example, the short-circuit photocurrent density of the ZnSe/Si heterojunction solar cell was improved by 57.6% from 11.75 to 18.52 mA cm(-2) compared to that without Ag NPs. Meanwhile, the responsivity and detectivity of the ZnSe:Sb NRs/Si heterojunction device increased from 117.2 to 184.8 mA W(-1), and from 5.86 × 10(11) to 9.20 × 10(11) cm Hz(1/2) W(-1), respectively.

Hidden coal gas fire spontaneous combustion troubles are one of the greatest threats to the coal safety production due to the gas explosion. In this paper, a novel method of prediction the hidden fire source is presented by means of choosing the concentration of CO gas as the indicator to detect the hidden coal gas fire location because CO gas is first reach the alarm threshold in the process of coal spontaneous combustion. The chaotic characteristics of CO gas are analyzed, and the duffing chaotic oscillator is used to detect the weak CO gas concentration signals, then the simulation model is established. The research experiment result shows that this method has high sensitivity for predicting the location of coal spontaneous combustion.

Product design which is one of the most important stages for manufacturing is a complex activity involving a great amount of knowledge. In this paper, knowledge is divided into three types: formula knowledge, diagram knowledge, table knowledge. Based on these requirements, knowledge base is constructed. This is used to store knowledge and to support the decision-making product design. First, the knowledge representation is formally described. Then, the knowledge navigation and search strategy is detailed. A specific section is dedicated to demonstrating the knowledge application techniques according to the different knowledge types that are proposed. The proposed methods are illustrated with examples. Finally, we conclude with the presentation of application performed with the knowledge application techniques.

Radial Basis Function (RBF) networks have simple network structures and fast convergence speed. In this paper, we propose a fuzzy neural network blind equalization algorithm based on radial basis function (FNN-RBF-BLE). The proposed algorithm defines the centers of RBF equalizer by analyzing the relationship of the input signal of equalizer and transmitted signal, therefore the structures of equalizer become simpler and the convergence speed become faster. Then, we use the Fuzzy C-Means clustering algorithm (FCM) divide the input signal of equalizer into each cluster center with different membership values and the mean square error (MSE) is reduced. The performance of the proposed algorithm is compared with blind equalization algorithm based on RBF (RBF-BLE). It is shown that a relatively low mean square error and fast convergence speed has been achieved.