Combination Machine Analysis and Design

针对大型焊接结构件的焊后加工问题，本文主要探讨双面镗车组合机床的设计问题。从工艺分析入手，对956Ⅱ装载机大型结构件后车架进行加工工艺分析，为确保焊后加工质量与各组件间的形位精度要求，对结构件各部件分清主次，使焊接、加工的基准统一，设计合理的工艺方案，并通过经济可行性分析，确定通过设计组合机床来完成加工任务。 本文重点阐述了工艺方案设计、组合机床设计、工装设计、刀具设计、液压系统设计、PLC控制设计等6个方面，经过分析论证，提出用闲置的两个镗孔车端面动力头与两个机械滑台来完成后车架铰接孔与四个端面的加工，工件用副车架支承架的孔定位，设计可平移微调的工装来确保4个端面的加工余量及相互间的位置尺...According to the problem of large structural part machining after welding, this article mainly discusses how to design two-end boring and turning combination machine tool. Starting with process analysis, this article carrys out machining process analysis for rear frame of Wheel loader Model 956Ⅱ. In order to guarantee machining quality after welding and the geometric precision among different asse...学位：工程硕士院系专业：信息科学与技术学院自动化系_控制工程学号：X20043103

Evidence that cells from experimental tumours can activate coagulation factor X.

The procoagulant activity of cells from some experimental tumours isolated in culture or in single-cell suspensions from ascitic fluid was investigated. Cells from Lewis lung carcinoma (primary and metastasis), Ehrlich carcinoma ascites and JW sarcoma ascites were able to shorten markedly the recalcification time of normal, Factor VIII- and Factor VII-deficient but not of Factor X-deficient human plasma. The same cells generated thrombin when mixed with a source of prothrombin and Factor X, absorbed bovine serum (as a source of Factor V), phospholipid and calcium chloride. Thrombin formation was not influenced by the presence of Factor VII. Cells from Sarcoma 180 ascites were completely inactive in both test systems. It is concluded that cells from some experimental tumours have the capacity to activate Coagulation Factor X directly. These findings suggest the existence of an alternative "cellular" pathway in the initiation of blood clotting distinct from both the intrinsic and extrinsic mechanisms

A global optimization approach to fractional optimal control

In this paper, we consider a fractional optimal control problem governed by system of linear differential equations, where its cost function is expressed as the ratio of convex and concave functions. The problem is a hard nonconvex optimal control problem and application of Pontriyagin's principle does not always guarantee finding a global optimal control. Even this type of problems in a finite dimensional space is known as NP hard. This optimal control problem can, in principle, be solved by Dinkhelbach algorithm [10]. However, it leads to solving a sequence of hard D.C programming problems in its finite dimensional analogy. To overcome this difficulty, we introduce a reachable set for the linear system. In this way, the problem is reduced to a quasiconvex maximization problem in a finite dimensional space. Based on a global optimality condition, we propose an algorithm for solving this fractional optimal control problem and we show that the algorithm generates a sequence of local optimal controls with improved cost values. The proposed algorithm is then applied to several test problems, where the global optimal cost value is obtained for each case

A new approach to second order optimality conditions in vector optimization

The aim of this paper is to establish some second order necessary and sufficient optimality conditions for a multiobjective problem where optimality is studied with respect to arbitrary closed convex cones. The proposed approach is an extension to the one recently given by the same authors

Composition theorems for generalized concave vector valued functions

The aim of this paper is to extend to the vector case some composition theorems and properties related to generalized concave scalar functions. The vector valued functions which will be used are defined by means of a partial order given by a closed convex cone with nonempty interior. Results about composition theorems concerning generalized concave scalar functions are also provided