Asian Transactions on Engineering

Volume: 02, Issue: 05, November 2012
ISSN 2221-4267

Title: High precision CNC machining of axisymmetric die cavities
Author(s): Sotiris L. Omirou and Marios M. Fyrillas
Paper ID: ATE-80214051
Pages: 1 - 9
Abstract: A high precision method is described for CNC milling of axisymmetric die cavities used to manufacture parts of revolution by processes such as casting, forging, injection, molding etc. The desired form of the cavities is achieved by selecting as generatrix curve (profile) any plane curve, implicitly or parametrically defined, which fulfills specific imposed by the user criteria. Tool center motion is generated by modeling each machining pass as a path composed of generatrix curve segments and semicircular arcs. The surface quality is controlled by keeping the distance between successive scallops within a programmed value. Each segment of the generatrix is processed by highly accurate real-time interpolation algorithm which generates cutting steps equal to the machine's resolution, while semicircular arcs are processed by the existing in all CNC systems standard circular motion. As it is shown, the whole machining task can be programmed in a single block of the part program. The effectiveness of the proposed system is verified by simulation tests for three representative applications.

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Title: Level measurement comparison between 3D vision system based on Kinect and ultrasonic industrial sensor
Author(s): Robinson Jiménez Moreno, Oscar Avilés S., Fabio Espinosa V.
Paper ID: ATE-90225059
Pages: 10 - 19
Abstract: This paper presents the development of a level control system using 3D machine vision techniques based on a single level-detector sensor (Kinect), in an arrangement of three tanks. Using image processing algorithms, each one of the tanks is classified within the video sequence as well as each one of the depth measurements is averaged regarding the cross sectional area of the surface of the tanks. This information is used to control the filling level for each tank using a proportional fuzzy controller and a proportional-derivative fuzzy controller. The measured levels by the Kinect were compared to those obtained with an industrial level sensor, concluding that Kinect offers a good measurement precision besides some others inherent advantages like price and multi-sensing.

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Author(s): Ibrahim M. Jomoah
Paper ID: ATE-30208053
Pages: 20 - 43
Abstract: The use of compact (window) air-conditioning units (A/Cs) in residential and institutional building to control indoor climate, has been tremendously increasing in KSA in the past 4 decades. The noise generated from these units could produce noise-pollution problems leading to annoying the occupants, interfering with their communication and causing general stress among them, as well as reducing their productivity and increasing work absenteeism and accidents. The present study, therefore, aimed to evaluating factors affecting A/C noise, and proposing remedial actions for eliminating or minimizing the noise levels. The study comprised a sample of 1,181 residential units in Makkah region, including houses, villas, residential apartments, furnished apartments and hotels, as well as 1,830 institutional buildings, including corner shops, hospitals and polyclinics office buildings, governmental organization and governmental and private schools. Results indicated that the use of A/Cs in building could create noise pollution problem in buildings, particularly in the hotels, furnished and residential apartments and corner shops. Factors affecting levels of generated noise in both residential and institutional buildings include: type (brand) of A/Cs, type of walls, insulations, floors, and windows, the method of fixing A/Cs, type of furniture and level of crowd.It has been recommended to consider these factors when selecting, installing and operating A/Cs, as well as considering their routine and meticulous maintenance.

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Title: Calculating Stress Intensity Factor (Mode I) for Plate with Central Crack: Review and Comparison between Several Techniques of Calculations
Author(s): Luay S. M. A. Al-Ansari
Paper ID: ATE-80202056
Pages: 44 - 56
Abstract: A comparison between six models, calculating stress intensity factor (SIF) mode I for central cracked plate with uniform tensile stress, is made in order to select the suitable model. These models are three theoretical models (i.e. classical model) and three numerical models. The three numerical models are half ANSYS model, quarter ANSYS model (finite element method) and weight function model. The geometry of the cracked plate (the width of the plate, the length of the plate and the crack length) and applied stress are the parameters that used to compare between the models. The three theoretical models can recognize the effect of the width of the plate, the crack length and applied stress but they failed to recognize the effect of the length of the plate. The three numerical models are success to recognize the effect of geometry and loading parameters. But the half ANSYS model gives a different response to the variation of the (H/W) ratio and that occurs due to finding the stress intensity factor (SIF) mode II. This leads to select the quarter ANSYS model as a suitable model calculating stress intensity factor (SIF) mode I for central cracked plate with uniform tensile stress.

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Title: Synchronous Generator Excitation Chatter-Free Sliding Mode Controller
Author(s): Ayokunle A. Awelewa, Isaac A. Samuel, James Katende, and Ayoade F. Agbetuyi
Paper ID: ATE-10217051
Pages: 57 - 62
Abstract: A chatter-free sliding mode controller (SMC) for synchronous generator excitation is presented in this paper. A linearized model of a single machine connected to an infinite bus is employed to design a variable-structure controller which not only stabilizes the system, but also ensures that this is maintained in the face of system parameter variations. Validating the robustness feature of an SMC, simulation results that show the dynamic performance of the system under both constant excitation and SMC-controlled excitation are presented.

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Title: Software package WinQSB in the function of automatisation of transport management system
Author(s): Marija D. Matotek
Paper ID: ATE-60221050
Pages: 63 - 69
Abstract: This paper deals with the possibilities of WinQSB software package for application in transport management. In this way, it has been demonstrated the solution for classic problem, which from the aspect of operational research, can be defined as follows: Transport problem needs defining the number of homogenous units, which should be arranged from many starting points to many destinations in order to decrease transport charges and increase the income. The main goal of the research is to demonstrate the usability of applications in companies where is necessary to take care about reduction of transport charges.

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Title: Development of Lane Configuration Adjustment Factors for the Capacity Analysis of Signalized Intersections.
Author(s): Dr. Md. Mizanur Rahman
Paper ID: ATE-40210054
Pages: 70 - 74
Abstract: The capacity analysis procedures for signalized intersections included in Highway Capacity Manual (HCM) needs to consider lane configuration (Lane position and lane number) of a given intersection. However, the attention given to this matter appears to be inadequate. The main objective of this paper is to examine the effects of lane configuration on the saturation flow at signalized intersections of Asian cities. This paper also aimed at developing the saturation flow rate correction factors for lane configuration at signalized intersections. Analysis of variance (ANOVA) was performed to evaluate whether the lane configuration (lane position and lane numbers) of a given intersection had a significant impact on the saturation flow rate. Saturation flow rate adjustment factors for lane configuration are developed dividing the prevailing saturation flow rate by ideal saturation flow rate. It is suggested by the analysis that lane configuration have significant impact on the saturation flow at signalized intersection approaches.

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Title: An Optimization of Plastic Injection Molding Parameters Using Taguchi Optimization Method
Author(s): Radhwan Hussin, Rozaimi Mohd Saad, Razaidi Hussin, Mohd Syedi Imran Mohd Dawi
Paper ID: ATE-80219056
Pages: 75 - 80
Abstract: During producing a product using injection molding process, various defects such as warpage, weld lines, shrinkage and sik mark can be occured, optimal setting up of injection molding process is very important to reduce the defect and controlling the quality defect of the injection molded product. The purpose of this paper is to minimizing warpage defect on Polycarbonate/Acrylonitrile Butadiene Styrene (PC/ABS) thermoplastic and simulates the injection molding process using Moldflow Plastic Insight software (MPI). The approach was based on Taguchi's Method and Analysis of Variance (ANOVA) has been implemented to analyze and optimize the processing parameters such as mold temperature, melt temperature, packing time, packing pressure, cooling time, cooling temperature, ambient temperature and runner size.

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Title: Experimental and Numerical Study of Oblique Crack Effect on Natural Frequency of Different Composite Plate Structure Types
Author(s): Muhsin J. Jweeg, Ali S. Hammood, and Muhannad Al-Waily
Paper ID: ATE-80203058
Pages: 81 - 91
Abstract: The natural frequency is studied for composite material strengthen by short fibers and long fibers, with the effect of crack orientation for different aspect ratio of plate and the type of plate fixing where simply supported in all edges. Two methods are used to find the natural frequency of composite plate: First method is an experimental method by applied a time varied load and admeasure the natural frequency of the plate. Second method is a finite element solution using ANSYS (ver. 14) program. A comparison made between the three methods and the error percentage is not exceeds of 8.5%. The amount of decreasing in natural frequency increases when the crack inclined with an angle than that without inclination angle, because the effect of the crack distributed on the both sides of the plate will be a bigger effect.

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