Analysis of the propagation of leaky magnetostatic modes in normally magnetized microstrip and slot lines

The propagation of leaky forward magnetostatic (MS) volume waves along ferrite-loaded microstrip and slot lines is analyzed. This phenomenon is studied by means of a numerical approach based on the residue calculus technique because of its good numerical convergence and stability. The proposed method allows for a quick and accurate computation of the phase and attenuation constants of the leaky MS modes. A comparative analysis between both microstrip lines and slot lines is carried out, and some new physical effects, such as MS resonances in the radiation loss, are reported. The advantages of the proposed method of analysis over other numerical methods, such as Galerkin's or moment methods, are also discussed.     

Using artificial intelligence to model heavy plate mill rolling

This research summary discusses the application of neural networks, evolutionary strategies, and other artificial intelligence techniques in the modeling and optimization of the models used for temperature, rolling force, and torque calculation in heavy plate milling.     

TIC: A timed calculus

TIC is a timed algebraic calculus which combines ideas from asynchronous and synchronous calculi. Time is introduced by assigning explicit time restrictions to the events of an asynchronous calculus. The semantics is defined in an operational way. Interleaving of behaviours is defined in such a way that a proper merge of events in time is achieved. Weak timed bisimulation is also defined. Examples are presented to show the applicability of the calculus to the study of timed behaviours.This work was partially supported by CICYT under the TIC program (MEDAS project)     

Ti/Al Interaction and Austenite Grain Control in Crankshaft Manufacturing with 38MnSiVS5 Steel

38MnSiVS5 steel is similar to 38MnVS6 steel (EN), the difference being the addition of a small Ti content. Typical Ti and Al contents in the chemical composition of 38MnSiVS5 steel are Ti=0.020 and Al=0.035 mass%. Both elements combine easily with nitrogen, especially Ti, and it has been observed that relatively high Al levels are harmful for austenite grain size control at reheating temperatures. In this work 38MnSiVS5 steel is used to manufacture a large number of castings, varying only the Ti and Al contents and obtaining ingots with a different Ti/Al ratio in each case. The results show that abnormal growth of the austenitic grain occurs irrespective of the Ti and Al contents, due fundamentally to the partial dissolution and coarsening of TiN precipitates. However, the steels with high Al contents present worse behaviour due to the formation of a second type of precipitates, namely AIN, which quickly dissolve between 1000 and 1100°C, causing a drastic decline in local pinning forces that gives rise to more pronounced abnormal growth of the affected grains.     

Optical properties of amorphous carbon thin films prepared by plasma deposition in a graphite hollow cathode

Carbon films have been produced using a graphite hollow cathode and an r.f. plasma of hydrogen or hydrogen and argon. No hydrocarbon gas was used. The films were subjected to heat treatments up to 700 °C in air. The optical properties of the films were studied using Fourier transform IR, UV-visible, Raman, ellipsometry and photoluminescence techniques before and after the annealing. Films prepared without argon have a narrower band gap and a different photoluminescence response from films prepared with argon. The index of refraction was seen to have values between 1.7 and 2.2 depending on the preparation conditions. The optical band gap of the films was generally greater than 2 eV and the annealing process both increased the gap and reduced the density of states responsible for the large photoluminescence signal.     

环缝错边容器的有限元分析与容限探讨

采用有限元方法对 1台封头与筒体具有较大错边量的容器进行了应力分析 ,得到了错边区域的应力分布状况 ,并对其进行应力强度评定。结果表明 ,该容器错边部位的应力是满足应力分析准则的。通过对存在不同错边量的容器进行应力分析 ,探讨了容器的错边容限 ,对含有错边缺陷在役容器是否合乎使用的判断具有一定指导意义     

错金工艺及对其运用的探讨

为了继承和发扬错金工艺，从其定义出发，探讨了该工艺在中国古代及国外的发展与应用以及笔者对该工艺的实验研究。针对在错金工艺实践过程中出现的问题，在查阅了相关的资料后，对传统错金工艺的实现方法提出了质疑。