Applied Mechanics and Materials Vol. 620

Abstract: The car repair workers would be injured in some part of body because of improper working postures. To reduce the injuries while repairing, changes must be made in the design of the car lying board. The improvement will be made according to the ergonomics theory, thus from the perspective of the comfortable working posture; analyzing from a qualitative nature to a quantitative nature, the design of the car lying board through man-machine analysis module of CATIA software on how to enhance the comfort of car repairing. That will make it possible for the car lying board to change its height and the angle of the pillow board according to the level of fatigue of man, so as to improve the comfort of car repairing. Also, it will provide an important reference to the design of related products.

Abstract: it is to make the designers for the virtual reality technology application in automobile modeling have a certain understanding, By comparing the traditional car model making process and the latest virtual technology . Compared with Industrial Modelling Design of Automobiles and Man-Machine Engineering, the VRT could save enormous manpower and the material resources. Futhermore, it has a revolutionary change in the aspects of modeling precision and modifiability. it provides technical direction for Automobile Modeling.

Abstract: The substation location is an important part of network planning . In this Paper, the optimal siting and site optimization mathematical model of classification are introduced , and the methods used in substation siting analyze many algorithms for a more comprehensive overview ; Finally,we offer some suggestions for the method of substation power market environment devlopment research .

Abstract: At present, the most common way of ultrasonic focusing is concave spherical self-focusing, ultrasonic focusing on lens and phased array ultrasonic focusing. Phased array ultrasonic focusing system is made up by multiple independent transducer unit array, according to the specific way and timing, real-time control of different arrays of ultrasonic signal phase. Established the ideal point source consisting of piezoelectric transducer phased array model 4 * 4 by the use of COMSOL, and results got the phased array focused in the simulation experiments.

Abstract: The T-junction model is simulated in Fluent by changing the curvature of branch pipe, and then the distribution characteristics of the annular flow was studied in T-junction distributor. The mass flow and pressure of the annular flow in this T-junction are studied, and the impact of Coanda Effect on the annular flow distribution characteristic is analyzed in oil-air two phases flow. The results show that, Coanda Effect affects the distribution of oil-air annular flow unevenly. The mass flow rate of air phase and the air velocity of outlet increase with decreasing the curvature, while the mass flow rate of liquid decrease with decreasing the curvature of the branch pipe connection; T-shaped junction inlet pressure is high, but the pressure gradient is small, the pressure gradient in the small curvature manifold is larger than that in the large curvature manifold.

Abstract: The aim of this investigation is to optimize the multiple performance characteristics of electrical discharge machining (EDM) for SKD 61 tool steel in gas media using grey relational analysis. The three most important machining characteristics namely material removal rate (MRR), electrode wear rate (EWR), and surface roughness (SR) were considered as the measures of the performance characteristics. A series of experiments were conducted according to an L18 orthogonal array based on the Taguchi experimental design method. The observed data obtained from the experiments were evaluated to determine the optimization of machining parameters correlated with multiple performance characteristics through grey relational analysis. Moreover, analysis of variance (ANOVA) was conducted to explore the significant machining parameters crucially affecting the multiple performance characteristics. In addition, the optimal combination levels of machining parameters were also determined from the response graph of grey relational grades for each level of machining parameter.

Abstract: This paper investigates the scheduling of the multi-crane operations in batch annealing process in an iron and steel enterprise so that the completion time of the last annealed coil (makespan) is minimized. The annealing process of each coil consists of two-stage: heating and cooling. To start heating (cooling) for each coil, a special machine named furnace (cooler) must be loaded on. Once the heating (cooling) is completed, the furnace (cooler) must be unloaded immediately without any delay by crane (job no-wait constraint). The aim of our studied problem is to schedule finite machines (furnaces and coolers) by cranes to process jobs under the consideration for avoiding collision between two adjacent cranes and satisfying job no-wait constraint. For solving the problem, we present a heuristic algorithm combining earliest job requirement and closest crane first. Through the theoretical analysis, we show the absolute performance bound of the proposed heuristic algorithm.

Abstract: This paper briefly introduces the cold-formed thin-walled steel residential system, the mechanical behavior analysis on stress of cold-formed thin-walled steel structure residential vertical load and horizontal load, and through compared with cold-formed thin-walled steel structure residential and traditional residential structure, summarized the characteristics of cold-formed steel residential. It is significant that the cold-formed steel residential system will be promoted and applied.

Abstract: In this paper, it is described that the design elements and the process of the recovery system for the by-product low-pressure steam of ammonia. And it is introduced the situation of application of this system, including the main equipments selection and control strategy. At last, the economic benefit after application is analyzed.

Abstract: In order to the difficult forming sheet metal part with the vertical wall to be formed by the multi-stage incremental forming, the algorithm of the recognition and modify the difficult forming surface of the vertical wall is studied. The method for generation of the technological model for multi-stage incremental forming is also presented. The case studies show that the algorithm is feasibility.