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关键词： 离合器   辅助换挡   无动力中断   自动变速器   换挡特性  

摘要： 提出一种仅用一个摩擦离合器实现无动力中断换挡的新型自动变速器——超越离合器辅助换挡自动变速器.该变速器采用摩擦离合器与超越离合器交替传递动力的方式实现连续换挡.为研究该自动变速器的换挡平顺性问题,搭建了两个挡位的6自由度变速器动力学模型,提出了换挡过程中离合器和动力源的协调控制策略,开展了仿真和台架试验研究.结果表明:所提升挡和降挡控制策略能有效降低换挡冲击,使得换挡时的冲击度保持在10m·s^(-3)以内.

关键词： 湿式双离合器   滑摩热量   钢片温度   温升影响因素  

摘要： 为了获取DCT变速器湿式双离合器结合过程热影响规律,以某湿式双离合自动变速器为研究对象,借助于Matlab/Simulink仿真分析软件建立湿式双离合器接合过程动力学模型,对离合器接合时摩擦副滑摩热量及钢片温升进行了热影响因素仿真分析,得到离合器接合时间、发动机转速、结合压力和摩擦钢片厚度等因素对摩擦副温度变化的影响规律,为不同摩擦片结构及工作状况时冷却油流量合理配置提供了理论依据。

关键词： 拖拉机   东方红   增压中冷   加强型   发动机   离合器   双作用   可靠性  

摘要： 东方红6105（LX1604）/6110（LX1804）拖拉机电控增压中冷发动机,动力强劲,油耗低。装配14吋加强型LUK双作用离合器,可靠性更高。基配12＋4挡加强型变速箱,性能可靠。可选装24＋8爬行挡,爬行挡速度小于4 m/min.

关键词： Drag torque modeling   High circumferential speed   Wobbling   Mechanical contact  

摘要： A mathematical model is established to predict the drag torque increment due to the mechanical contact at high circumferential speed in open wet clutches. The fluid hydrodynamic actions are coupled simultaneously with the kinematic position of the tilted friction plate. The drag torque due to mechanical contact at high speed is estimated by presenting a rigid-body impact model. The calculation results are validated by experiments performed on an open multi-plate wet clutch test rig. The model calculation demonstrates that the drag torque also becomes higher with larger flow rates of lubricant at high circumferential speed.

关键词： Prebiotic   Brain   Mental health   Inflammation   Immune system   Type 2 diabetes  

摘要： Objective: The aim of this trial was to determine the efficacy of a resistant dextrin on immune-mediated inflammation and hypothalamic-pituitary-adrenal axis in women with type 2 diabetes mellitus (T2DM). Methods: Females (n = 55) with T2DM were randomly allocated into intervention group (n = 30) and control group (n = 25), in which they received 10 g/d of Nutriose (R) 06 (a resistant dextrin) or maltodextrin for 8 weeks, respectively. Fasting blood samples were taken to measure immune system related parameters like white blood cell count, CD4, CD8, interferon-gamma (IFN gamma), interleukins (IL12, 14, 110), cortisol, tryptophan (TRP), ACTH (Adrenocorticotropic hormone), Kynurenine (KYN) and plasma lipopolysaccharide (LPS) at the beginning and end of trial. Mental health was assessed using general health questionnaire (GHQ) and depression, anxiety and stress scale (DASS). Results: Resistant dextrin caused a significant decrease in levels of cortisol, KYN, KYN/TRP ratio, IFN gamma, IL12, IFN gamma/IL10 ratio, LPS, and a significant increase in the monocyte, GHQ DASS, CD8, IL10, IL4 in the intervention group as compared with baseline. A significant decrease in the level of LPS (-6.20 EU/mL, -17.8%), IFN gamma (-0.6 pg/ml, -26.8%), cortisol (-2.6 mu g/dl, -20.9%), IFN gamma/IL10 ratio (0.01, 10%), GHQ (-5.1, -12.5%), DASS (-10.4, -38.4%), KYN/TRP ratio (6.8, 29.1%), and a significant increase in levels of CD8 (6.4%, 6.1%) and 110 (2.6 pg/ml, 21.6%) in the intervention group as compared with the control group (P < 0.05). No significant changes were observed in white blood cell count, CD4, CD4/CD8 ratio, ACTH, KYN, TRP, IL4 and IL12 in the intervention group as compared with the control group (P > 0.05). Conclusion: Supplementation of Nutriose (R) 06 may have beneficial effects on mental health and the immune system response in women with T2DM. (C) 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

关键词： Double limit rotation axis   Five-axis machine tool   Rotation angle   Postprocessor   JAVA  

摘要： The five-axis machine tool with special structure requires the professional postprocessor in order to exploit the capabilities of the machine tools. Compared with the standard five-axis machine, the five-axis machine tools with special structure such as double limit rotation axis (DLRA) requires the implementation of the angle optimization to achieve the process requirements of complex parts. In this paper, a rotation angle optimization algorithm for the DLRA of the head tilting-head rotation (HT-HR)-type five-axis machine tool is proposed to overcome the problem that rotation angle is limited in machining complex parts. First, the initial correction condition is determined based on the rotation range of the rotation axes, in the case that the tool contact point is fixed;the rotation angles of the correction area are optimized. Then, a post processor for HT-HR five-axis machine tool with angle optimization function is developed based on the kinematic model. Furthermore, the proposed approach is validated for simulation and practical experimental with an impeller specimen. Results of the verification tests show that the presented angle optimization algorithm can accurately revise the rotation angle in the processing so as to improve the machining scope of machine tools. This method also provides a certain reference to solve the problem of limited rotation angle for other similar machine.

关键词： Axial myopathy   SGCA   Sarcoglycans   NGS  

摘要： Mutations in the SGCA gene cause limb girdle muscular dystrophy type 2D (LGMD2D). We report a family with three affected siblings with a mild phenotype consisting of late onset glutei and axial muscle weakness produced by a new mutation in the SGCA gene leading to a partial expression of the alpha-sarcoglycan protein. The MRI showed muscle atrophy involving paraspinal, pelvic and thigh muscles and a dystrophic pattern was observed in the muscle biopsy. Exome sequencing revealed a homozygous intronic deletion of SGCA and mRNA analysis showed the presence of three different transcripts. The presence, though in a lower proportion, of wild type transcript leads to a milder presentation of the disease. Although clinical symptoms did not entirely correspond with a sarcoglycanopathy, a compatible muscle MRI drove us to look for changes in the sarcoglycan genes. These cases are an example of how clinical, radiological and pathological data enriches the interpretation of exome analysis. (C) 2018 Elsevier B.V. All rights reserved.

关键词： Strain gages  

摘要： In many real time applications, information of transmitted torque is a mandatory input of the embedded control strategies. In the most of cases, the use of a physical torque sensor (strain gauge) is compromised by cost and bulk reasons and the torque is not measured. Unfortunately, the need of an embedded torque measurement is a general real time application problem and can only be solved through an accurate embeddable estimation method. This issue is especially common in automotive industry concerning the powertrain management for example. A virtual strain gauge based on an unknown input Takagi-Sugeno discrete observer designed in the angular domain and a shaft angular deformation estimation method is proposed as a universal torque estimator. The static torque estimation is ensured rebuilding the shaft torsion angle by a virtual tooth adding method into the encoder sensors disposed at each edge of the shaft. The observer performs the dynamic part of the transmitted torque through a mass-spring model structure of the shaft. The virtual strain gauge has been applied on real torque estimation issues in automotive application such as the engine and the clutch torque estimation. Simulation and real time results have permitted to validate the feasibility, the versatility and the accuracy of the virtual strain gauge. (C) 2018 Elsevier B.V. All rights reserved.