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Automatic lane change of vehicles requires driving at the fastest possible speed while ensuring no collision situations. However, regular control is not robust enough to handle unexpected situations or respond to lane separation. To solve these problems, an automatic lane change decision model based on dueling double deep Q-network(D3QN) reinforcement learning model is proposed. The algorithm processes the environmental vehicle information fed back by the internet of vehicles, and then obtains actions through strategies. After the actions are executed, the neural network is trained according to given reward function, and finally the automatic lane change strategy is realized through the trained network and reinforcement learning. The three-lane environment built by Python and the vehicle simulation software CarMaker are used to carry out simulation experiments. The results show that the algorithm proposed has a good control effect, making it feasible and effective. [ABSTRACT FROM AUTHOR]

In order to study the influence of the stress direction during underground engineering excavation on the strength of weakly cemented soft rock, the soft rock samples were obtained from the coal mine roadway engineering soft rock and the GDS(Global Digital Systems) hollow cylindrical test system was used to determine the average fixed principal stress. The deviation stress under the action of the rotation of the principal stress axes, the stress path of the soft rock mechanics, and rotation angle of the principal stress axes of weakly consolidated soft rock specimen were studied, and the stress-strain characteristics as well as the influence of the strength characteristics was determined. Based on the test results and power function model, an empirical equation of the shear strain of weakly consolidated soft rock under the principal stress axis was established. The results show that the deformation of weakly consolidated soft rock accumulates with the rotation of the principal stress axis, and with the rotation angle of the principal stress axis increases, the axial strain and shear strain rates increase rapidly, and the cumulative deformation also increases.The rotation of the principal stress axis accelerates the accumulation of the axial strain of the specimens.The shear formular can effectively predict the shear strain variation law of weakly consolidated soft rock under the stress axis rotation. Additionally, it can be applied in the deformation prediction of practical engineering. [ABSTRACT FROM AUTHOR]

A conditional generative adversarial network-based high perceptual image compression(HPIC) model was proposed to obtain a compressed image that conforms to human visual perception. In HPIC， the original image was encoded and quantized based on a hyper prior probability model. A generator based on the conditional additional label and residual module was used for the reconstruction of the compressed image， and a discriminator based on the convolutional neural network was used to distinguish the difference between the compressed image and the real image. Based on the bit rate-distortion-perception optimization theory to design the loss function， the perceptual distortion metric was chosen based on the eigenvalues of the pre-trained inception network to achieve image compression reconstruction with high perceptual quality on the one hand， and use the adversarial generation network loss to eliminate compression artifacts and improve the compression accuracy on the other hand. The experimental results show that HPIC achieves a good balance in the bit rate-distortion-perception tradeoff and outperforms the current common algorithms in all perceptual metrics scores， even though the latter uses twice as much bit rate as ours. HPIC can achieve compression with high perceptual quality. [ABSTRACT FROM AUTHOR]

Aiming at multi-focus image fusion, the complementary information at each scale is fused in a targeted manner using a multi-scale fusion method. First, the source image is decomposed into a background layer and a detail layer using the L0 gradient minimization smoothing method, and then a fractional-order edge detection mask is used to preserve the edge information in the background layer, and a fractional-order gradient energy operator is introduced in the detail layer for weight assignment. The experimental results show that the proposed fractional-order gradient energy operator is more sensitive than the integer-order gradient energy clarity operator, which is consistent with the human visual perception. The fusion method proposed effectively avoids artifacts and block effects in the fused images, and retains the source image information more fully. [ABSTRACT FROM AUTHOR]

The admissibility issue of discrete singular systems was mainly studied. Applying restricted equivalent transformations of the discrete singular system， a new necessary and sufficient condition was proposed to ensure discrete singular system admissible. By introducing an intermediate matrix to configure partial poles of system matrix such that the closed-loop system is regular， a state feedback controller was designed to make the closed-loop system admissible. Using similar methods， the controller design problem of uncertain discrete singular systems was discussed as well， a sufficient condition of robust stabilization for uncertain discrete singular systems was obtained. All the methods proposed in this article are strictly linear matrix inequalities(LMI). Two numerical examples verify the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Ｉｎ ｏｒｄｅｒ ｔｏ ａｖｏｉｄ ｔｈｅ ｂｌｕｒｒｉｎｇ ｏｆ ｉｍａｇｅ ｂｙ ｃｌａｓｓｉｃａｌ ｍｅｄｉａｎ ｆｉｌｔｅｒ, ａ ｎｏｉｓｅ ｄｅｔｅｃｔｉｏｎ ｍｏｄｅｌ ｗａｓ ｅｓｔａｂｌｉｓｈｅｄ. Ａ ｓｗｉｔｃｈｉｎｇ ｆｉｌｔｅｒ ｗａｓ ｄｅｓｉｇｎｅｄ ｂｙ ｄｅｔｅｃｔｉｎｇ ｎｏｉｓｅ. Ｗｈｅｎ ｔｈｅ ｄｅｔｅｃｔｉｏｎ ｐｏｉｎｔ ｉｓ ｎｏｉｓｙ, ｔｈｅ ｍｅｄｉａｎ ｆｉｌｔｅｒ ｗａｓ ｕｓｅｄ ｆｏｒ ｄｅｎｏｉｓｉｎｇ. Ｗｈｅｎ ｔｈｅ ｄｅｔｅｃｔｉｏｎ ｐｏｉｎｔ ｉｓ ｎｏｎ-ｎｏｉｓｙ ｐｏｉｎｔ, ｔｈｅ ｆｒａｃｔｉｏｎａｌ ｄｉｆｆｅｒｅｎｔｉａｌ ｆｉｌｔｅｒ ｗａｓ ｕｓｅｄ ｔｏ ｅｎｈａｎｃｅ ｔｈｅ ｉｍａｇｅ. Ｔｈｅ ｐｒｏｐｏｓｅｄ ａｌｇｏｒｉｔｈｍ ｃａｎ ｎｏｔ ｏｎｌｙ ｅｆｆｅｃｔｉｖｅｌｙ ｒｅｍｏｖｅ ｔｈｅ ｓａｌｔ ａｎｄ ｐｅｐｐｅｒ ｎｏｉｓｅ ｉｎ ｔｈｅ ｉｍａｇｅ, ｂｕｔ ａｌｓｏ ｅｎｈａｎｃｅ ｔｈｅ ｉｍａｇｅ, ｓｏ ｔｈａｔ ｔｈｅ ｉｍａｇｅ ｒｅｔａｉｎｓ ｔｈｅ ｄｅｔａｉｌｓ ｉｎｔａｃｔ ｗｈｅｎ ｔｈｅ ｅｄｇｅ ｉｓ ｐｒｏｔｒｕｄｉｎｇ. Ｓｅｌｅｃｔｉｎｇ “Ｌｅｎａ” ａｎｄ ｏｔｈｅｒ ｃｌａｓｓｉｃ ｉｍａｇｅｓ ｆｏｒ ｍｕｌｔｉｐｌｅ ｅｘｐｅｒｉｍｅｎｔｓ ａｎｄ ａｎａｌｙｓｉｓ, ｔｈｅ ｒｅｓｕｌｔｓ ｓｈｏｗｅｄ ｔｈｅ ｅｆｆｅｃｔｉｖｅｎｅｓｓ ｏｆ ｔｈｅ ｐｒｏｐｏｓｅｄ ａｌｇｏｒｉｔｈｍ ｉｎ ｉｍａｇｅ ｄｅｎｏｉｓｉｎｇ ａｎｄ ｅｎｈａｎｃｅｍｅｎｔ. [ABSTRACT FROM AUTHOR]

The observer for the uncertain fractional-order system with sensor fault and system measurement noise is developed. By using the method of augmented matrix and the invariant property of matrix rank， the uncertain fractional-order system is augmented into the singular fractional-order uncertain system. Based on the linear matrix inequality approach of stability criterion for fractional-order systems， an asymptotic stability criterion of the error dynamic system with fractional-order satisfying 1 [ABSTRACT FROM AUTHOR]

OBJECTIVE: To probe into the clinical efficacy and safety of methylprednisolone (MP) combined with monosialotetrahexosylganglioside sodium for injection (GM-1) in treatment of acute spinal cord injury (ASCI). METHODS: 88 patients with ASCI admitted into Jingzhou the Second People's Hospital from Jan. to Dec. 2015 were selected to be divided into observation group and control group via the random number table, with 44 cases in each. The control group were treated with MP, while the observation group additionally received GM-1 based on the control group. The efficacy and adverse drug reactions were compared between two groups. RESULTS: After treatment, the improvement of motor function and sensory function in two groups had been significantly improved, and observation group was better than control group, with statistically significant difference (P < 0. 05). The incidence of adverse drug reactions in observation group was 9. 1% (4/44), and control group was 11. 4% (5/44), the difference was not statistically significant (P > 0. 05). CONCLUSIONS: The efficacy of MP combined with GM-1 in treatment of ASCI was significant with high safety. [ABSTRACT FROM AUTHOR]

Objective To understand the hygiene and safety status of living and drinking water in the schools of Anlu City to provide a basis for improving the living and drinking water quality in schools. Methods A total of 138 samples of living and drinking water in whole schools of Anlu City during 2015 were collected,including well water,tap water,water from cold out-let and hot outlet of bottled water. The hygienic status of water quality was detected according to the related standard. Results Among 138 water samples,72 samples were unqualified with the disqualification rate of 52.2%,among them,which of tap water was 60.7%(12/28),which of well water was 66.7%(32/48),which of cold outlet water in bottled water was 48.4%(15/31) and which of hot outlet water was 25.8%(8/31). The disqualification rate of tap water in urban schools was 0,which was lower than 77.3%(17/22) in rural schools,the difference was statistically significant (χ2=11.802,P<0.05). The item disqualification indexes were mainly microbial and sensory indexes ,the small parts were the general chemical and toxic indexes. The disqualification rate of free chlorine in villages and towns tap water was 54.5%(12/22),indicating that villages and towns tap water was not fully dis-infected. Conclusion The quality of living and drinking water in the schools of Anlu City is poorer , especially in villages and towns schools. The hygienic facility investment,maintenance,supervision and management of school living and drinking water should be strengthened for ensuring the hygiene and safety of drinking water in teachers and students. [ABSTRACT FROM AUTHOR]

目的 探讨并发重度肢体缺血性坏疽伴感染的下肢动脉硬化闭塞症 (ASD) 患者血管腔内介入术后截肢 的影响因素, 构建术后截肢风险预测模型。方法　选择行血管腔内介入术治疗的 106 例 ASD 并发重度肢体缺血性 坏疽伴感染患者, 根据术后是否截肢分为截肢组 20 例和非截肢组 86 例。收集患者临床资料、感染严重程度、感染病 原菌分布、实验室指标等。采用多因素 Logistic 回归分析影响患者截肢的因素, 根据筛选出的危险因素和回归系数 建立风险预测模型, 并采用 ROC 曲线分析该模型对患者术后截肢的预测价值。结果　截肢组年龄、ABI 及合并糖尿 病、卢瑟福6级、吸烟史比例高于非截肢组 (P均<0.05)。截肢组重度感染比例高于非截肢组 (P<0.05)。106 份样本 中共检出 148 株病原菌, 其中截肢组检出34株病原菌, 以奇异变形菌、大肠埃希菌比例最高; 非截肢组检出 114 株病 原菌, 以铜绿假单胞菌、金黄色葡萄球菌比例最高。截肢组 WBC、NLR、PLR、CRP、PCT 高于非截肢组, Alb、Hb 低于 非截肢组 (P均<0.05)。多因素 Logistic 回归分析显示, 合并糖尿病、卢瑟福分级为6级、重度感染、ABI 低、病原菌为 奇异变形菌、Alb 及 Hb 水平降低是 ASD 并发足部重度肢体缺血性坏疽伴感染患者截肢的危险因素 (P均<0.05)。以 上述危险因素构建的预测模型为: 0.865+0.860×糖尿病+1.651×卢瑟福 6 级+1.296×重度感染-1.308×ABI+1.607× 奇异变形菌-1.153×Alb-1.183×Hb, 该模型预测术后截肢的曲线下面积为 0.904 (0.824～0.982), 灵敏度为 94.0%, 特异度为 87.4%。结论 并发重度肢体缺血性坏疽伴感染的 ASD 患者血管腔内介入术后仍有较高截肢率, 糖尿 病、重度感染、ABI<0.52、奇异变形菌等会增加术后截肢风险, 以上述危险因素构建的预测模型对并发重度肢体缺 血性坏疽伴感染的 ASD 患者血管腔内介入术后截肢有较高的预测价值。 [ABSTRACT FROM AUTHOR]

In order to study the shear strength characteristics of polypropylene fiber-reinforced cement aeolian sand, the orthogonal test method was used to conduct unconsolidated undrained triaxial (UU) test to study the effects of fiber content, fiber length, cement content, and water content on the shear strength of fiber-reinforced cement aeolian sand. The results show that the main and secondary factors influencing the shear strength of fiber-reinforced aeolite sand are cement content, fiber length, water content, and fiber content.The optimal test ratio is cement content 10%, fiber length 12 mm, water content 8% and fiber content 0.2%. The peak stress and strain of cement eolian sand can be significantly increased by adding the appropriate amount of fiber into the sample. The cohesion increases first and then decreases with the increase of fiber content, and increases with the increase of fiber length. The influence of fiber content on internal friction angle is small. The research results can provide the scientific basis for the prevention and treatment of fiber-reinforced cement eolian sand roadbeds. [ABSTRACT FROM AUTHOR]

Objective: This study is to research and develop a simple and rapid method to directly differentiate the induced pluripotent stem cells (iPS) into functional hepatocytes in vitro. Methods: According to the development of normal hepatocytes in vitro, a simplified method was designed for differentiation of iPS cells into endodermal cells. The phenotypes of endodermal cells was identified by qPCR and flow cytometry, and then these cells were further differentiated into hepatocyte-like cells. The characteristics and functions of hepatocytes were identified by qPCR, ELISA and immunofluorescence. Results: The results showed that the mRNA/protein expression of OCT4 and NANOG were decreased significantly, and the mRNA/protein expression of endodermal cell-related genes, CXCR4, FOXA2 and HNF4A,were increased significantly at day 7 after iPS cell induction. Hepatocyte specific marker genes ALB, TDO2, RBP4, G6PC and hepatocyte drug enzyme genes CYPs were significantly upregulated at day 15, and high levels of albumin and urea were produced simultaneously. Positive PAS glycogen staining and active uptake and release of indocyanine green were observed in the induced hepatocytes. It was confirmed that the hepatocyte-like cells had the partial functions of primary hepatocytes. Conclusion: This easy and efficient induction method can be used in differentiation of iPS cells into functional hepatocytes by mimicking the process of liver organogenesis in vitro. This study provides the possibility for massive production of iPS-derived hepatocytes and their applications in cellular therapy and drug screening models. [ABSTRACT FROM AUTHOR]

Objective: This study is to research and develop a simple and rapid method to directly differentiate the induced pluripotent stem cells (i PS) into functional hepatocytes in vitro. Methods: According to the development of normal hepatocytes in vitro, a simplified method was designed for differentiation of i PS cells into endodermal cells. The phenotypes of endodermal cells was identified by q PCR and flow cytometry, and then these cells were further differentiated into hepatocyte-like cells. The characteristics and functions of hepatocytes were identified by qPCR, ELISA and immunofluorescence. Results: The results showed that the m RNA/protein expression of OCT4 and NANOG were decreased significantly, and the m RNA/protein expression of endodermal cell-related genes, CXCR4, FOXA2and HNF4A,were increased significantly at day 7 after i PS cell induction. Hepatocyte specific marker genes ALB, TDO2, RBP4, G6PC and hepatocyte drug enzyme genes CYPs were significantly upregulated at day 15, and high levels of albumin and urea were produced simultaneously. Positive PAS glycogen staining and active uptake and release of indocyanine green were observed in the induced hepatocytes. It was confirmed that the hepatocyte-like cells had the partial functions of primary hepatocytes. Conclusion: This easy and efficient induction method can be used in differentiation of i PS cells into functional hepatocytes by mimicking the process of liver organogenesis in vitro. This study provides the possibility for massive production of i PS-derived hepatocytes and their applications in cellular therapy and drug screening models. [ABSTRACT FROM AUTHOR]

In this study, we adopted steam gasification of biomass, and pine fuel rods as the experimental objects. We used gas chromatography and Fourier transform infrared spectrometer to analyze components of gas and tar change during the process of gasification. We also determined catalytic performance of modified dolomite (bentonite as the carrier, dolomite as the active component and a small amount of load limonite) as temperature rose. Our experiment results showed that, high-temperature made steam gasification of biomass intensified so that steam reforming reaction intensified and thus contributing to H2 gas volume fraction in the overall upward trend in the gasification components, but hydrocarbon gas volume fraction in downward trend. Gasification gas carries gasification tar into the catalyst layer, which makes tar catalytic cracked, promotes steam reforming reaction intensified and thereby changes the composition of gasification gas. Under the condition of steam gasification with modified dolomite catalyst at 750 ℃, H2 volume fraction was 45.77%±0.23%. Compared to hydrogen-rich action of catalytic and non-catalytic conditions dolomite, gasification temperature dropped to 100oC. With the rise of temperature, modified dolomite promoted the increase of carbon oxides and hydrocarbons volume fraction, but hydrogen-rich degree weaken. The calcined dolomite contained MgO/CaO as active ingredients can cause the long carbon chain cracked in aliphatic hydrocarbons, conducive to the production of radical hydrogen ion, and be helpful to generate hydrogen. When Fe as a promoter was used, it was activated to Fe3+ by high temperature steam, and converted to Fe2+ after promoting tar cracking. Modified dolomite not only promoted the scission of carbon chain length on the hydrocarbon side chain and the formation of H2, but also promoted opening reactions of aromatic ring, decarboxylation and dehydroxylation reactions, thereby making tar after pyrolysis easily to be converted into small molecule gas carbon containing, which helped to reduce the production of tars gasified and improved the gasification efficiency. The catalyst active center Fe3+ decreased at higher temperature, which made the gaining weight of homemade catalyst after catalysis reduced to a minimum of 900 ℃, but compared to dolomite, the change of color and shape of modified dolomite between front and rear catalytic was small, which reflected the mechanical strength and surface area carbon optimized. The catalytic activity of dolomite was secondly to nickel-based catalyst, but it had potential economic value with cheaper price. In this study, we compared to steam gasification of biomass with dolomite catalyst, explored the catalytic properties of modified dolomite, which would provide useful information of dolomite modification method and studies of steam gasification of biomass. The purpose of this research was to promote the use of dolomite catalysts, and our results showed that they can be used for the treatment of tailings and to deepen the study of biomass steam gasification. [ABSTRACT FROM AUTHOR]

The (Nd1-xMMx)-Fe-B(x=0, 0. :3, 0.5, 0.7, 1) sintered magnets were prepared in this paper by the method of two main phases with Misch-Metal (MM) . The magnetic properties decreased with the increase of MM content. The XRD results show that the phase composition of (Nd1 - x MMx)-Fe-B sintered magnet was still 2: 14: 1 with the increase of MM content. However, ReFe2 phase appeared when the MM content reached 30 wt% and the intensity of the diffraction peak of ReFe2 also increased with the increasing MM content. The micro morphology, element distribution and domain structure of (Nd0.5MM0.5)-Fe-B sintered magnet were analyzed by SEM-EDS, and the results shows that La and Ce elements diffused into some Nd-Fe-B main phase grains in MM containing magnets. The domain structure of the magnet without MM possessed standard bar domains observed by magneto-optical Kerr microscope, while the domain structure of magnet grains with MM tended to maze domains and La and Ce addition promoted the maze domain structure formation. In addition, it is found that transgranular domains were easy to form bet ween the grains lacking rare earth rich phase. [ABSTRACT FROM AUTHOR]

Grasping the change rule and the distribution of rural settlements in farming-pastoral zone has significant meaning to rectifying residential areas, optimizing layout, and implementing rural revitalization strategic planning. This paper took Damao Banner of Baotou city in Inner Mongolia, a typical farming-pastoral ecotone in the north of Yinshan Mountain, as the study region, and we used historical data materials such as land cover types, toponymy records, scoio-economic data came from the Statistical Yearbook of Damao Banner in 1996, 2012 and 2016, based on Kernel density analysis and model of Gravity Migration to explore and reveal the spatial distribution characteristics and evolution of rural settlements. Meanwhile, its influencing factors mainly include elevation, slope, aspect, distance to water, distance to road, distance to towns, national culture, population and government policies, etc. We analyzed the intrinsic relationship between the spatial distribution of the rural settlements and the factors by using GIS (geographic information system) spatial analysis software. The results showed that: 1) the distribution characteristic of rural settlements in Damao Banner in 2012 was obvious, reaching a peak of 1.416/km2. From 1996 to 2016, the distribution center of Damao Banner’ rural settlements moved to the southeast and gradually approached Bailingmiao Town. 2) The influence of DEM and slope on the distribution of rural settlements was inverted U-shaped. It increased first and then decreased gradually. The peak value of DEM was 1 400-1 600 m, and the peak value of slope was 3.056°-5.446°. The choice of aspect was gradually inclined to the south aspect, southwest aspect and the proportion increased year by year, but some rural settlements were still distributed on the shady aspect, for example north aspect and northeast aspect, which was affected by geographical environment, national culture, and government policy. The spatial distribution of the rural settlements of Damao Banner did not show obvious near-water characteristic in terms of the distance to water area, but they mostly distributed in 7-10 km away from the water. 3) The road distance showed obvious near-road orientation. In 2016, the number of rural settlements distributed within the range of 0-1 000 m from the road accounted for 98.77%, indicating that the roads and settlements had mutual influence and interaction. Traffic significantly changed the spatial pattern of the rural settlements, and had evident distance attenuation effect. The number of the spatial distribution of rural settlements occupied the largest proportion when it was 20-40 km away from the town in 2012 and 2016. It meant that the radiation effect of central town on rural settlements was limited to a certain extent, and the spatial distribution of rural settlements was far away from central town. In agricultural region and pastoral region of Damao Banner, the number of rural settlements had different characteristics with their population. In 1996 and 2016, the number of Mongolian population in the pastoral region was significantly positively correlated with the number of rural settlements. The Mongolian nomadic culture promoted the distribution of residential areas with a highly dispersed feature of “Giant Stars”. Also government policies had an important impact on the spatial distribution and pattern of rural settlements in Damao Banner. Therefore, the results of this study can provide a reference for rectifying residential areas, optimizing layout, and implementing rural revitalization strategic planning in these ethnic areas. [ABSTRACT FROM AUTHOR]