排序方式: 共有43条查询结果,搜索用时 31 毫秒
31.
Babur Ozcelik Fehmi Erzincanli 《The International Journal of Advanced Manufacturing Technology》2005,25(5-6):527-532
The handling process of a single ply of cotton woven fabrics from a stack in the textile industry is done by workers. Cost-effective automatic handling of the fabrics is becoming an increasingly important issue to reduce the unit cost of the final product .In this study, transporting speeds in the horizontal direction of the woven fabrics were investigated using a non-contact end-effector. A Cartesian robot, which has an x and z axis, was used for handling the cotton woven fabrics. The movement process of a single woven fabric ply from a stack was experimentally shown to find out percentage of success rate of the system. Although the experiments were restricted with small square fabric plies of 100 mm×100 mm sizes, this process could also be applied for products with different shapes. 相似文献
32.
Eyup Bagci Babur Ozcelik 《The International Journal of Advanced Manufacturing Technology》2006,28(7-8):680-687
The drilling process is highly non-linear. Coupled with a thermo-mechanical machining, localized heating and temperature increases
in the workpiece are caused by the rapid plastic deformation of the workpiece and by the friction along the drill-chip interface.
The cutting temperature at the tool-chip interface is an important factor which directly affects workpiece surface integrity,
tool wear, and hole diameter and cylindricity in the drilling process. In this study, the effects of sequential dry drilling
operations on the drill bit temperature were investigated both experimentally and numerically. Drill temperatures were measured
by inserting standard thermocouples into the coolant (oil) hole of TiN/TiAlN-coated carbide drills. Experimental studies were
conducted using two different workpiece materials, AISI 1040 steel and Al 7075-T651. The drill bit temperature was predicted
using a numerical computation with Third Wave AdvantEdge finite element method (FEM) software, which is based on Lagrangian
explicit. The results obtained from the experimental study and finite element analyses (FEA) were compared. Reasonable agreement
between the measured and calculated drill bit temperature results were found for sequential dry drilling. 相似文献
33.
In this study, the resistance of liquefied-petroleum gas (LPG) tanks produced from carbon steel sheet metal of different thicknesses has been investigated by bursting pressure experiments and non-linear Finite Element Method (FEM) method by increasing internal pressure values. The designs of LPG tanks produced from sheet metal to be used at the study have been realized by analytical calculations made taking into consideration of related standards. Bursting pressure tests have been performed that were inclined to decreasing the sheet thickness of LPG tanks used in industry. It has been shown that the LPG tanks can be produced in compliance with the standards when the sheet thickness is lowered from 3 to 2.8mm. The FEM results have displayed close values with the bursting results obtained from the experiments. 相似文献
34.
Alsubhi Khalid Imtiaz Zuhaib Raana Ayesha Ashraf M. Usman Hayat Babur 《浙江大学学报:C卷英文版》2020,21(6):917-930
Frontiers of Information Technology & Electronic Engineering - Rapidly increasing capacities, decreasing costs, and improvements in computational power, storage, and communication technologies... 相似文献
35.
Zh. T. Erdyneev G. Babur A. A. Geltser 《Journal of Communications Technology and Electronics》2018,63(3):220-225
The sliding signal processing method interpreted as the range observation technique for syntheticaperture radar systems is discussed. The given method enables us to shift the observed ranges, thereby eliminating the maximum range restriction inherent to the standard de-ramping processing method. The operational capability of the method is demonstrated using radar images obtained from the single received implementation but exhibiting different detection ranges. It is revealed that the method under consideration is efficient upon reduction of nonlinear distortions caused by the nonideal operation of a voltage-controlled oscillator. 相似文献
36.
Kianfar F Chowdhry BZ Antonijevic MD Boateng JS 《Drug development and industrial pharmacy》2012,38(10):1207-1220
Bioadhesive buccal films are innovative dosage forms with the ability to adhere to the mucosal surface and subsequently hydrate to release and deliver drugs across the buccal membrane. This study aims to formulate and characterize stable carrageenan (CAR) based buccal films with desirable drug loading capacity. The films were prepared using CAR, poloxamer (POL) 407, various grades of PEG (plasticizer) and loaded with paracetamol (PM) and indomethacin (IND) as model soluble and insoluble drugs, respectively. The films were characterized by texture analysis, thermogravimetric analysis (TGA), DSC, scanning electron microscopy, X-ray powder diffraction (XRPD), and in vitro drug release studies. Optimized films were obtained from aqueous gels comprising 2.5% w/w κ-CAR 911, 4% w/w POL 407 and 6% w/w (PM) and 6.5% w/w (IND) of PEG 600 with maximum drug loading of 1.6% w/w and 0.8 % w/w for PM and IND, respectively. TGA showed residual water content of approximately 5% of films dry weight. DSC revealed a T(g) at 22.25 and 30.77°C for PM and IND, respectively, implying the presence of amorphous forms of both drugs which was confirmed by XRPD. Drug dissolution profiles in simulated saliva showed cumulative percent release of up to 45 and 57% of PM and IND, respectively, within 40?min of contact with dissolution medium simulating saliva. 相似文献
37.
Babur Ozcelik Hasan Oktem Hasan Kurtaran 《The International Journal of Advanced Manufacturing Technology》2005,27(3-4):234-241
In this study, optimum cutting parameters of Inconel 718 are determined to enable minimum surface roughness under the constraints
of roughness and material removal rate. In doing this, advantages of statistical experimental design technique, experimental
measurements, artificial neural network and genetic optimization method are exploited in an integrated manner. Cutting experiments
are designed based on statistical three-level full factorial experimental design technique. A predictive model for surface
roughness is created using a feed forward artificial neural network exploiting experimental data. Neural network model and
analytical definition of material removal rate are employed in the construction of optimization problem. The optimization
problem was solved by an effective genetic algorithm for variety of constraint limits. Additional experiments have been conducted
to compare optimum values and their corresponding roughness and material removal rate values predicted from the genetic algorithm.
Generally a good correlation is observed between the predicted optimum and the experimental measurements. The neural network
model coupled with genetic algorithm can be effectively utilized to find the best or optimum cutting parameter values for
a specific cutting condition in end milling Inconel 718. 相似文献
38.
Babur Ozcelik 《International Communications in Heat and Mass Transfer》2011,38(8):1067-1072
This study optimized effect of injection parameters and weld line on the mechanical properties of polypropylene (PP) moldings. The mold with an insert was designed to create weld line in the experimental specimen. Melt temperature, packing pressure and injection pressure were investigated to study their effects on the mechanical strength of specimens with/without weld lines. Taguchi's L9 (33) orthogonal array design was employed for the experimental plan. Mechanical properties such as maximum tensile load, extension at break and charpy impact strength (notched) of the specimens were measured. Signal to noise ratio for mechanical properties of PP using Taguchi method was calculated and effect of the injection parameters and weld line on mechanical properties was determined using the analysis of variance (ANOVA). Linear models were also created by using regression analysis. The most important parameter affecting the maximum tensile load and the extension at break (for specimen without/with weld line) was injection pressure and melt temperature, and for charpy impact strength (notched) (without/with weld line) was melt temperature and injection pressure, respectively. 相似文献
39.
40.
In the first part of the two companion papers, theoretical formulation of the multiscale micromechanical constitutive model that couples the anisotropic damage mechanism with the viscoplastic deformation is presented. In the second part of these companion papers the numerical simulation of the computational aspects of the theory are elaborated. The perforation and penetration problem of metal matrix composites (MMCs) due to high impact loading is simulated. In this sense, the computational aspects of the developed theory are elaborated here. First, the verification of the developed model is performed through its numerical implementation in order to test the model predictions of the material characteristic tests. This encompasses uniaxial monotonic loading and unloading under different strain rates, uniaxial cyclic loading, and uniaxial loading and relaxation. The verified material routine of the developed model is then implemented in the explicit finite element code ABAQUS via the user defined subroutine VUMAT at each integration point in order to analyze the projectile impact and penetration into laminated composite plates. 相似文献