Yazarlar

  • MakaleYalnız künye2018
    COMPARISON OF FEM SOLUTION WITH ANALYTICAL SOLUTION OF CONTINUOUS AND DISCONTINUOUS CONTACT PROBLEM

    Kaya, Yusuf; Polat, Alper; Özsahin, Talat Sukru

    The continuous and discontinuous contact problem of a homogeneous layer loaded with three rigid flat blocks and resting on the elastic semi-infinite plane was investigated in this study by using the finite element method (FEM). All surfaces are assumed to be frictionless. The homogenous layer was loaded by means of three rigid flat blocks whose external loads are Q and P (per unit thickness in z direction). Two dimensional finite element analysis of the problem was performed using ANSYS package program. Analyzes were performed for loading conditions which are Q=P, Q=2P, Q=4P, Q=8P and Q=10P, and different values of block widths, distances between blocks and shear modulus. The initial separation loads and initial separation distances (lambda(cr), chi(cr)) between the homogeneous layer and the elastic semi-infinite plane were determined for continuous contact condition. The length of the separation zone was obtained for discontinuous contact condition. In addition to these, normal stress distributions between the layer and the semi-infinite plane were determined for continuous and discontinuous contact conditions. As a result of the study, the analytical results, and the results of the finite element method were shown by comparing as graphs and tables.

    AtıfWoS5
    Web of Scienceİncele
  • MakaleYalnız künye2017
    FUZZY LOGIC BASED INDIRECT VECTOR CONTROL OF SQUIRREL CAGE INDUCTION MOTOR

    Nur, Ahmet; Omaç, Zeki; Öksüztepe, Eyyup

    Squirrel cage induction motors are widely used in industry. These induction motors need smart control applications for high performance. In this paper an indirect vector control of squirrel cage induction motor is modelled mathematically. The mathematical model is moved to simulation using Matlab/Simulink software. For improvement, the indirect vector control simulation is based on fuzzy logic. Eventually, the simulation results for fuzzy logic speed control of induction motor are obtained for different reference speeds. The results showed effectiveness of fuzzy control system for indirect vector control of squirrel cage induction motor simulation model.

  • MakaleYalnız künye2017
    PROJECT MANAGEMENT IN HEALTHCARE: A CASE STUDY FOR PATIENT FLOW EVALUATION IN AN EMERGENCY ROOM USING FUZZY CPM AND FUZZY PERT

    Gül, Muhammet; Güneri, Ali Fuat; Günes, Gizem

    An ideal healthcare system is considered as a system that provides the most quality service level, lower costs and unlimited access. Any delay in patient flow may result in undesired consequences and losses in healthcare facilities such as hospitals and their sub units. Project management is defined as application of techniques to project activities to meet the project requirements. It has techniques that can help healthcare facilities and units standardize care and quality, reduce costs, improve effectiveness and decrease prolonged waits. The current study is carried out in an emergency department of a university hospital to understand the patient flow of the department with respect to the Fuzzy Critical Path Method (FCPM) and Fuzzy Program Evaluation Review Technique (FPERT). The reason for incorporating fuzzy sets is stemmed from that fuzzy numbers are more effective for high uncertainty processes as in emergency departments. Activities affecting patient flow through the ED are identified and project network is drawn. 1500 patients' data about the times of each activities are obtained from the observed ED. Findings through application of FCPM and FPERT, the expected time for completion of the project, the critical path and slack times are determined.

    AtıfWoS2
    Web of Scienceİncele