@article { author = {Marzoog, Rasha and Alduroobi, Ahmed A. Alduroobi and Al-Zubaidy, Sawsan}, title = {Complex Surface Representation and Machining Time Estimation Upon Three Types of End Mill Cutter}, journal = {Engineering and Technology Journal}, volume = {37}, number = {9A}, pages = {354-358}, year = {2019}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.37.9A.1}, abstract = {The accuracy of data transition between CAD and CAM has been playing a great role in the product life cycle, and eventually, the product quality. As products complexity increased, the need to robust technique to data transition increased. On the other hand, Machining simulation facilitates deciding the process parameters. The aim of the present research is divided into two aims: first: building a free form surface and transforming its data accurately from CAD to CAM without any distortion. Second: study the milling process using different end cutters geometry and make a comparison between those in terms of machining time at a constant scallop height (s.h.). The study passed through three steps, first: A mathematical model and computer program had been built for non-uniform B-spline surface creation. The output points are stored in a format to be easily imported. Second: importing the data into manufacturing simulation program to emulate the milling process. Three types of milling tools with different end cutter had been used (flat, ball, and toroidal). Third, use a CIMCO edit package to estimate machining time for the three tools. A conclusion had been made that the surface data had been transformed accurately into the simulation process. Another conclusion was, with fixed (s.h.) the ball end mill takes more time than toroidal, which in turn takes more time than flat.}, keywords = {data transition,non-uniform B-spline surface,milling process,machining time}, url = {https://etj.uotechnology.edu.iq/article_169043.html}, eprint = {https://etj.uotechnology.edu.iq/article_169043_59073e45da035a32ce1b96c1cd95add8.pdf} } @article { author = {Ataiwe, Tariq and Khalaf, Abbas and Mohammed, Israa}, title = {Smoothing Smartphone GPS Raw Measurements}, journal = {Engineering and Technology Journal}, volume = {37}, number = {9A}, pages = {359-363}, year = {2019}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.37.9A.2}, abstract = {This  research aims  to  investigate  the  smoothing  of  the  pseudo-range raw  measurements  of  the  smartphone  using  a  Hatch  filter.  The  measurements  of  smartphones  suffer  from  high  noise  generated  from  low-cost  antennas  and  oscillators, which are designed to work in a certain way. These types of low-cost antennas  and  oscillators  are  entirely different  from  geodetic  instruments,  which  are  designed  for  high  accuracy  positioning.  The  GPS  measurement  data  were  collected   using   a   Huawei   P10   device,   41   minutes   and   24   seconds   GPS   observation  time  with  sampling  intervals  of  1  second  using  Geo++  Android  application.  The  GPS  measurements  are  processed  using  standalone  (epoch  by  epoch)  method,  by  MATLAB  software  developed  by  the  authors,  as  a  part  of  a software  package  for  processing  smartphone  GPS  measurements.  The  errors  in  raw  measurements  in  the  Easting,  Northing,  and  Up  (ENU)  components  when  using  standalone  (epoch  by  epoch)  method  are  ranging  from  -50m  to  30m,  and  the errors after applying the Hatch filter are reduced to have ranged from -10m to  5m,  the  raw  data  were  very  noisy  and  funded  it  has  many  cycles  slips  as  a  result of low-cost antennas and oscillators of smartphone’s. The cycle slips in the measurements  were  detected  and  found  that  it  was  the  result  of  jumping  the  errors to 27 m in northing and 43 m in up.}, keywords = {Hatch filter,GPS smoothing,GPS Smartphone}, url = {https://etj.uotechnology.edu.iq/article_169044.html}, eprint = {https://etj.uotechnology.edu.iq/article_169044_43d7b9ee5a01933cbf3e3c10a151581d.pdf} } @article { author = {Al-Badairy, Ali and Al-Duroobi, Ahmed and Tawfiq, Maan}, title = {Point Cloud Pre-Processing and Surface Reconstruction Based on Chord Algorithm Technique}, journal = {Engineering and Technology Journal}, volume = {37}, number = {9A}, pages = {364-368}, year = {2019}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.37.9A.3}, abstract = {3D laser scanner is one of the modern technologies, which used to obtain the geometric information about the 3D scanned object surface. But, there are some problems that are associated with this technique such as the huge number of obtained points which require high memory to save and the required data processing processes. This paper proposed a data simplification algorithm for point cloud of a scanned object using 3D laser scanner (Matterand Form) in a manner to extract the necessary geometric features, which arerepresented by points for a 3D object. This algorithm based on theinstantaneous calculation of chord height of each set of adjacent points in thepoint cloud. A MATLAB environment was used to build a proposedsimplification algorithm program. Then this program was applied using aproposed case study. The result which was obtained from the application of theproposed algorithm and surface fitting process for the proposed case studyproved the effectiveness of the proposed algorithm in data simplification. Thepercent of data which was ignored as noisy data point was (24%) of the totalnumber of data point in applying the algorithm for two attempts.3D laser scanner is one of the moderntechnologies, whichused toobtain the geometric information about the 3D scanned object surface.But,there are someproblemsthatareassociated with this technique such as thehuge number of obtained pointswhichrequire high memory to saveandtherequired data processing processes.This paper proposed a data simplificationalgorithm for point cloud of ascanned object using 3D laser scanner (Matterand Form) in amanner to extract the necessary geometric features, whicharerepresented by points for a 3D object. This algorithm based ontheinstantaneous calculation of chord height of each set of adjacent points in thepoint cloud. A MATLAB environment wasused to build a proposedsimplification algorithm program. Thenthis programwasapplied using aproposed case study.The result which was obtained fromtheapplicationoftheproposed algorithm and surface fitting process for the proposed case studyproved the effectiveness of the proposed algorithm in data simplification.Thepercent of data which was ignored as noisy data point was (24%)of thetotalnumber of data point in applying the algorithm for two attempts.}, keywords = {Chord Algorithm,Point Cloud,Surface Reconstruction}, url = {https://etj.uotechnology.edu.iq/article_169045.html}, eprint = {https://etj.uotechnology.edu.iq/article_169045_b57393d2655cd9b43170adee0a082580.pdf} } @article { author = {Al-Zubaidi, Aseel}, title = {Recycling of Waste Paraffin Wax by the Addition of SiO2 Nano-Powders to Improve Thermal Conductivity}, journal = {Engineering and Technology Journal}, volume = {37}, number = {9A}, pages = {369-373}, year = {2019}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.37.9A.4}, abstract = {Paraffin wax is an important material used in thermal energy storage (TES) systems. The thermal conductivity of the material is an important parameter that decides the degree of exploitation of the paraffin wax in TES systems. The thermal conductivity is improved by the addition of silicon oxide nanoparticles (1%, 2%, 4%, and 6%) to the paraffin wax. The average size of the SiO2 particles is equal to 38 nm. The addition of SiO2 nano-particles at very small ratios was found to enhance the thermal conductivity of the paraffin wax considerably. SiO2 nanoparticles, add to paraffin wax, have a significant effect in enhancing the thermal storage characteristics of paraffinParaffin wax is an important material used in thermal energy storage(TES) systems. The thermal conductivity of the material is an importantparameterthatdecides the degree of exploitation of the paraffin wax in TESsystems. The thermal conductivity is improved by the addition of silicon oxidenanoparticles (1%, 2%, 4%,and 6%) to the paraffin wax. The average size of theSiO2particles is equal to 38 nm. The additionof SiO2nano-particles at verysmall ratios was found to enhance the thermal conductivity of the paraffin waxconsiderably. SiO2nanoparticles, add to paraffin wax, havea significant effectin enhancing the thermal storage characteristics of paraffin}, keywords = {thermal conductivity,waste Paraffin wax,SiO2nano powders}, url = {https://etj.uotechnology.edu.iq/article_169046.html}, eprint = {https://etj.uotechnology.edu.iq/article_169046_1354d9682ae3a5fb6c312f2c31db9b3b.pdf} } @article { author = {Ahmed, Fayyadh}, title = {A Compact Single-Feed Patch Antenna with Frequency and Polarization Diversity}, journal = {Engineering and Technology Journal}, volume = {37}, number = {9A}, pages = {374-383}, year = {2019}, publisher = {University of Technology-Iraq}, issn = {1681-6900}, eissn = {2412-0758}, doi = {10.30684/etj.37.9A.5}, abstract = {A new compact single feed square ring patch antenna using meandered 4λ transformer is designed, for frequency and polarization diversity. The proposed antenna is constructed from a square ring patch antenna, and two orthogonal meandered cascaded 4λ transformer (OMCT), incorporated with six switches for frequency and polarization reconfiguration purposes. The OMCT with switches is necessary to get good impedance bandwidth (BW) and axial ratio bandwidth (ARBW) for circular polarization state. In addition, it utilized to excite the antenna at two orthogonal locations, with equal magnitude and quadratic in phase, for achieving circular polarization mode at resonant frequencies 2.44GHz, 4.7GHz, and 5.6GHz. Moreover, it can excite the antenna as non-orthogonal modes for various other frequency bands, such as 2.89 GHz, 3.49 GHz, 4.9 GHz, 5.2GHz, 5.49GHz, 6.16GHz and 3.1GHz as linear polarization (LP) state. The proposed antenna has a compact low profile planar structure with area equal to 23mm2. Simulation and measured results show that the proposed antenna demonstrates a reasonable impedance bandwidth, and axial ratio in the circularly polarized state. Simulation results have been obtained from commercial CST-2014 Microwave Studio. The proposed antenna is fabricated for simulation result verification, and the implemented antenna is tested using R&S ZVL13 Vector Network Analyzer. The experimental confirms the simulation results.}, keywords = {patch antenna,antenna reconfiguration,Circular Polarization,axial ratio}, url = {https://etj.uotechnology.edu.iq/article_169047.html}, eprint = {https://etj.uotechnology.edu.iq/article_169047_97208c66bcb1ccceae4c2d75e0a4e82b.pdf} }