다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

This paper presents control and coordination algorithms for groups of vehicles. The focus is on autonomous vehicle networks performing distributed sensing tasks where each vehicle plays the role of a mobile tunable sensor. The paper proposes gradient descent algorithms for a class of utility functions which encode optimal coverage and sensing policies. The resulting closed-loop behavior is adaptive, distributed, asynchronous, and verifiably correct.

Coverage control for mobile sensing networks

A review on the attention mechanism of deep learning

Thermal barrier systems have been the subject of vigorous research and development activities over the past few years, driven by the demands for enhanced reliability and substantially higher operating temperatures envisaged for the next generations of gas turbine engines. The menu of candidate materials and architectures has expanded considerably, including numerous concepts based on zirconia as well as radically different materials, multilayers and modulated distributions of porosity and chemical composition. Advances in deposition processes enable increased flexibility for tailoring composition and microstructure to local requirements within the coating system, e.g. for thermal insulation, control of interdiffusion, enhanced resistance against environmental degradation and condition monitoring. Many challenges remain but healthy and growing collaborations between the science and technology communities bode well for future progress in this area.

Emerging materials and processes for thermal barrier systems

Multi-objective meta-heuristics: An overview of the current state-of-the-art

Surface modelling and mesh generation for simulating superplastic forming

High performance components, such as poppet valves, connecting rods, and pistons are manufactured from materials that pro- vide the necessary performance characteristics to withstand tough operating conditions. These materials usually possess high values of yield strength, Young's modulus, fatigue strength, and maintain them over a range of temperatures. Low density is also useful in compo- nents subjected to rapid speed changes. However, high performance materials, such as titanium alloys and stainless steels usually have a high density or are too costly to be used extensively. In many applications, high performance properties are required on particular surfaces or contact points, and are not necessary throughout the entire body of the component. One way of achieving this is to make components with more than one strategically located material. For practical reasons, normally the maximum number of alloys would be two. The work described in this paper is a preliminary investigation of the use of forging to produce bi-metallic components, through the production of a spur gear form. The experimental and simulation work described in this paper, provides knowledge of the effects of process variables on the outcome of forging bimetallic gears.

Investigation of Material Flow in Forging Bi-metal Components

Experimental and theoretical evaluation of a high-accuracy uni-axial creep testpiece with slit extensometer ridges

Effects of die land length and geometry on curvature and effective strain of profiles produced by a novel sideways extrusion process

For a metal forming process, the uniaxial tensile properties of a material are the most fundamental and important properties to investigate. Solution heat treatment, forming and in-die quenching (HFQ®) is a patented process to form complex shape panel components using aluminium alloys at high efficiency and low cost. A Gleeble materials thermo-mechanical simulator was used to conduct uniaxial tensile testing of AA6082 under HFQ® conditions. A set of grips were specially designed to reduce the heat loss of specimen during testing in a Gleeble and allow the strain measurement by using digital image correlation (DIC) system. A large dog-bone specimen with parallel length of 80mm was designed to minimise the temperature gradient along the gauge section. Temperature gradient was measured and uniaxial tensile tests were conducted at the range of deformation temperature of 350-535 °C and the range of strain rate of 0.1-4 /s. The uniaxial tensile properties of AA6082 at different temperatures and strain rates under HFQ® conditions were summarised and the viscoplastic response of the material was discussed.

Jianguo Lin

Papers

Surface modelling and mesh generation for simulating superplastic forming

Investigation of Material Flow in Forging Bi-metal Components

Experimental and theoretical evaluation of a high-accuracy uni-axial creep testpiece with slit extensometer ridges

Effects of die land length and geometry on curvature and effective strain of profiles produced by a novel sideways extrusion process

Investigation of Uniaxial Tensile Properties of AA6082 under HFQ® Conditions