微型离心泵泵叶三层式滑块机构三板模具设计

针对微型离心泵泵叶塑件成型模具设计困难的问题，设计了一种改进型三板点浇口模以用于该泵叶塑件的成型。塑件的浇注成型应用3个点浇口来进行平衡注塑，以控制塑件成型变形。模腔布局为1模1腔。针对塑件叶槽区域脱模困难问题，设计了一种3层3次复合抽芯脱模用于难脱模叶槽部位特征的脱模，机构中，将叶槽部位特征的成型块分割成2层成型件后，机构的第一次抽芯动作由弹簧驱动上层滑块实施上层成型块的抽芯；机构的第二次抽芯由斜导柱驱动实施下层成型块的抽芯；最后，由弯销驱动基座滑块带动2个侧抽芯滑块向外抽芯，以让出塑件完全顶出脱模的运动空间。第二次抽芯、第三次抽芯的驱动动力分别由模架模板的第三次开模、第四次开模打开来进行驱动。塑件的最终脱模由油缸驱动顶针板及顶杆顶出而实现塑件的完全脱模。基于塑件、流道脱模及抽芯机构的动作需要，将典型三板点浇口模架改进为四板4次开模点浇口，从而能使塑件、流道废料及驱动滑块机构分次按序来实施抽芯脱模。模具脱模机构动作设置合理，机构结构设计巧妙，模具整体工作可靠，有较好的设计参考价值。     

重复采动覆岩裂隙率空间分布相似模拟研究——以陕北矿区为例

由于水资源短缺,陕北矿区利用采空区储存矿井水进行再利用,采空区储水量与采动裂隙空间分布密切相关,为准确预测采空区储水量,基于工作面上覆岩层断裂分带划分结果,确定煤矿地下水库的主要储水空间为垮落带与断裂带的裂隙空间,建立了采动覆岩裂隙率空间分布的计算方法,采用相似模拟试验得出了柠条塔矿1^-2煤和2^-2煤重复采动后上覆岩层的下沉曲线,计算出重复采动覆岩裂隙率在垂直和水平方向的空间分布情况。结果表明:沿垂直方向,随着高度增加,覆岩裂隙率逐渐减小,1^-2煤开采后岩层裂隙率由1.87%逐渐下降为1.18%,2^-2煤开采后,裂隙率由12.85%下降为4.11%;沿水平方向,垮落带、断裂带和弯曲下沉带的裂隙率在采空区边缘附近都会产生2个峰值,并且峰值位置逐渐向采空区中央移动,1^-2煤开采后,中间压实区的最大裂隙率为1.21%,两边离层区的最大裂隙率为2.19%,2^-2煤开采后,压实区和离层区最大裂隙率分别为16.1%和6.54%;重复开采后,上覆岩层的裂隙率显著增加,有...     

连续纤维增强复合材料3D打印中国专利分析

以连续纤维增强复合材料3D打印领域的中国专利数据为分析样本，从专利申请的时间分布、申请人状况、专利技术分布等多角度详细剖析了国内连续纤维增强复合材料3D打印专利技术的产业发展状况。     

Engineering knowledge formalization and proposition for informatics development towards a CAD-integrated DfX system for product design

Target design methodologies (DfX) were developed to cope with specific engineering design issues such as cost-effectiveness, manufacturability, assemblability, maintainability, among others. However, DfX methodologies are undergoing the lack of real integration with 3D CAD systems. Their principles are currently applied downstream of the 3D modelling by following the well-known rules available from the literature and engineers’ know-how (tacit internal knowledge).This paper provides a method to formalize complex DfX engineering knowledge into explicit knowledge that can be reused for Advanced Engineering Informatics to aid designers and engineers in developing mechanical products. This research work wants to define a general method (ontology) able to couple DfX design guidelines (engineering knowledge) with geometrical product features of a product 3D model (engineering parametric data). A common layer for all DfX methods (horizontal) and dedicated layers for each DfX method (vertical) allow creating the suitable ontology for the systematic collection of the DfX rules considering each target. Moreover, the proposed framework is the first step for developing (future work) a software tool to assist engineers and designers during product development (3D CAD modelling).A design for assembly (DfA) case study shows how to collect assembly rules in the given framework. It demonstrates the applicability of the CAD-integrated DfX system in the mechanical design of a jig-crane. Several benefits are recognized: (i) systematic collection of DfA rules for informatics development, (ii) identification of assembly issues in the product development process, and (iii) reduction of effort and time during the design review.     

A survey of outlier detection in high dimensional data streams

The rapid evolution of technology has led to the generation of high dimensional data streams in a wide range of fields, such as genomics, signal processing, and finance. The combination of the streaming scenario and high dimensionality is particularly challenging especially for the outlier detection task. This is due to the special characteristics of the data stream such as the concept drift, the limited time and space requirements, in addition to the impact of the well-known curse of dimensionality in high dimensional space. To the best of our knowledge, few studies have addressed these challenges simultaneously, and therefore detecting anomalies in this context requires a great deal of attention. The main objective of this work is to study the main approaches existing in the literature, to identify a set of comparison criteria, such as the computational cost and the interpretation of outliers, which will help us to reveal the different challenges and additional research directions associated with this problem. At the end of this study, we will draw up a summary report which summarizes the main limits identified and we will detail the different directions of research related to this issue in order to promote research for this community.     

Design of data feature-driven 1D/2D convolutional neural networks classifier for recycling black plastic wastes through laser spectroscopy

In this study, two types of convolutional neural network (CNN) classifiers are designed to handle the problem of classifying black plastic wastes. In particular, the black plastic wastes have the property of absorbing laser light coming from spectrometer. Therefore, the classification of black plastic wastes remains still a challenging problem compared to classifying other colored plastic wastes using existing spectroscopy (i.e., NIR). When it comes the classification problem of black plastic wastes, effective classification techniques by the laser spectroscopy of Fourier Transform-Infrared Radiation (FT-IR) with Attenuated Total Reflectance (ATR) and Raman to analyze the classification problem of black plastic wastes are introduced. Due to the strong ability of extracting spatial features and remarkable performance in image classification, 1D and 2D CNN through data features are designed as classifiers. The technique of chemical peak points selection is considered to reduce data redundancy. Furthermore, through the selection of data features based on the extracted 1D data with peak points is introduced. Experimental results demonstrate that 2DCNN classifier designed with the help of 2D data feature selection as well as 1DCNN classifier shows the best performance compared with other reported methods for classifying black plastic wastes.     

电力工程项目管理的三要素分析

现今社会经济正在迅速发展中，电力工程领域也得到了较为良好的发展。但在此领域发展中，项目管理问题较为突显。文章主要是对电力工程项目管理的三要素进行了分析研究，以此帮助有效提升电力项目的管理工作效率及质量。     

三维机织间隔复合材料结构对其力学性能的影响

以玻璃纤维为原料,设计3种不同结构的三维机织间隔织物,采用手糊成型工艺制备三维机织间隔复合材料,研究了其在压缩、剪切、弯曲等载荷作用下的力学特性,并分析了材料结构对其力学性能的影响。结果表明,相同高度(20 mm)、相同间隔(30 mm)的3种三维机织间隔复合材料的压缩强度和剪切强度均表现为:三维纤维间隔复合材料<"X"型间隔复合材料<三维织物间隔复合材料,其压缩强度分别为0.52,0.72,1.66 MPa,剪切强度分别为0.22,0.28,0.36 MPa;3种三维机织间隔复合材料的弯曲强度基本相同,均为4.30 MPa左右。     

对甲基苯磺酸催化合成三乙酰没食子酸

以没食子酸与乙酸酐为原料,对甲基苯磺酸作催化剂,合成三乙酰没食子酸,考察了原料配比、催化剂用量、反应时间、反应温度对产品的影响。结果表明,酰化反应较佳的工艺条件是：n（没食子酸）∶n（乙酸酐）∶n（对甲基苯磺酸）=1∶2∶0.5,反应时间为1.5 h,反应温度为60℃,此时三乙酰没食子酸的收率为77.58%。     

Ionic liquid recovery alternatives in ionic liquid‐based three‐phase partitioning (ILTPP)

Ionic liquid‐based three‐phase partitioning (ILTPP) is a promising technique to recover high‐added value proteins at the liquid–liquid interface. Its economic and environmental performance highly depends on the net ionic liquid consumption. Alternatives to maximize the fraction of ionic liquid that can be recycled are studied. It is demonstrated that the addition of extra salt, previously proposed in literature, has a very limited effect on ionic liquid recovery for relatively high protein concentrations in the feed stream, and that it may even lead to an increase of the ionic liquid losses under certain conditions. However, small additions of salt are shown to be effective and profitable from an economic point of view. Vacuum evaporation is shown to allow for the complete ionic liquid and salt recovery, reinforcing the sustainability and viability of ILTPP processes. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3577–3586, 2014