基于回归树和AdaBoost方法的刀具磨损评估

本文利用高速数控铣刀铣削中不同侧面方向的切削力和振动信号以及声发射信号均方根值,以数据驱动的形式对刀具磨损进行了拟合评估. 在本次研究中,分别从时域、频域和时频联合域上探索与刀具磨损相关的敏感特征,具体特征提取方法包括时域统计分析、频域上的快速傅里叶变换（FFT）和时频联合分析的小波变换（WT）. 本文中,决策树被用于回归问题而非分类问题,用于评估刀具磨损值. 同时,引入AdaBoost算法对回归树模型进行提升,并从模型的准确性、稳定性和适用性三个方面上综合对比了提升的决策树回归模型和原模型的性能. 研究表明,AdaBoost算法提升的回归决策树模型在预测的准确性和稳定性上都有一定程度上提高,并且在面向全新刀具磨损预测的适用性上也取得了不错的提升效果.     

JavaEE的Web页面中操纵Word报表

基于Java EE的报表项目,介绍JavaEE的动态页面中利用Word生成报表的方法,描述了Web页面中嵌入Word,并把数据库中取出的数据封装为JSON格式,定位地填充到Word中指定的位置。     

巧用Access实现一种条形码可自动生成的录取通知书打印报表

将一种条形码技术,结合Access数据库报表,实现一个条形码可自动生成,且具有自动套打功能的录取通知书打印报表,解决了在招生结束后短时间内完成录取通知书的制作工作,在新生报到时,工作人员只需使用扫瞄器读取通知书上的条形码信息就能迅速准确定位到学生,大幅提高了迎新的效率和准确性。     

Tool path smoothing of a redundant machine: Application to Automated Fiber Placement

Automated Tape Laying and Fiber Placement of composite materials are the two principal automated processes used for fabrication of large composite structures in aeronautical industry. The aluminum parts produced by High Speed Machining tend to be replaced by carbon fiber composite parts realized with these processes. However, structural parts present reinforcement zones which disturb the tool path follow-up and generate an increase of the manufacturing time. Thus, this paper deals with the optimization of tool paths of a 7-axis machine tool of Fiber Placement with the objective of reducing the manufacturing time while ensuring the requested quality of the final part. In this paper, two complementary methods are detailed. The first method takes advantage of the degree of redundancy of the machine tool to decrease the kinematic loads of the control joints. The second method aims to smooth the orientation of the machine head along the tool path while ensuring quality constraints. These two methods are then applied on a test tool path and bring to a significant decrease of the manufacturing time (32.9%).     

TCP-aware network coding with opportunistic scheduling in wireless mobile ad hoc networks

This paper presents a scheme that employs TCP-aware network coding with opportunistic scheduling to enhance TCP throughput in wireless mobile ad hoc networks. Specifically, it considers a TCP parameter, congestion window size, and wireless channel conditions simultaneously to improve TCP throughput performance. Evaluation of this scheme is carried out by using ns2 simulations in different scenarios. The results show that the proposed scheme gives approximately 35% throughput improvement in a high mobility environment and about 33% throughput increase in no or low mobility environment as compared to traditional network coding with opportunistic scheduling. This paper also proposes a new adaptive-W (i.e., adaptive Waiting time) scheme whose objective is to adaptively control waiting time of overheard packets that are stored in a buffer to achieve tradeoff between throughput and overhead.     

The State of the Art in Topology‐Based Visualization of Unsteady Flow

Vector fields are a common concept for the representation of many different kinds of flow phenomena in science and engineering. Methods based on vector field topology are known for their convenience for visualizing and analysing steady flows, but a counterpart for unsteady flows is still missing. However, a lot of good and relevant work aiming at such a solution is available. We give an overview of previous research leading towards topology‐based and topology‐inspired visualization of unsteady flow, pointing out the different approaches and methodologies involved as well as their relation to each other, taking classical (i.e. steady) vector field topology as our starting point. Particularly, we focus on Lagrangian methods, space–time domain approaches, local methods and stochastic and multifield approaches. Furthermore, we illustrate our review with practical examples for the different approaches.     

Effects of electronic outlining on students' argumentative writing performance

This study examined the effect of electronic outlining on the quality of students' writing products and how outlining affects perceived mental effort during the writing task. Additionally, it was studied how students appropriate and appreciate an outline tool and whether they need explicit instruction in order to engage in planning. To answer these questions, the writing products and self‐report data from 34 tenth‐grade students of a Dutch pre‐university school were analysed. Students wrote two similar argumentative texts with or without an outline tool. Results show that electronic outlining improves the quality of students' argumentative texts and decreases mental effort. Answers to a retrospective questionnaire showed that a short instruction on the outline tool was sufficient for students to understand its working and that most students experienced the tool as beneficial. Finally, results indicate that without specific instruction on text planning, students hardly devote any time to this important aspect of writing.     

Java过程蓝图

1 引言计算机应用正进入网络时代,Java是一种广泛使用的网络编程语言,被称之为网络上的“世界语”。Java作为一种程序设计语言不仅具有简单、面向对象、分布式、解释执行、鲁棒、安全、平台无关、可移植、高性能、多线程以及动态性等特点,更重要的是它支持以网络为中心的新型计算模式——Java计算模式,从而使Ja-     

基于银税联网的税费代收系统

介绍了一个基于银税联网的税费代收系统的设计。     

巧用FANUC系统的刀具半径补偿功能

介绍了对刀尖补偿功能的作用、原理和使用方法 ,以车轮轮缘踏面的加工程序为例 ,说明刀具半径补偿功能的具体应用