Study of Corrosion Resistance of Co-Cr-Mo Surgical Implants Alloy in Artificial Saliva
Muna
Khethier Abbass
author
Sami
Abualnoun Ajeel
author
Haitham
M. Wadullah
author
text
article
2014
eng
Co-Cr-Mo alloy has been used for biomedical implant for a number of years. In this study, ASTM F-75 Cobalt-base substrate specimen was immersed in artificial saliva at 37 + 1 ºC to study the corrosion resistance properties. Surface of specimen before and after the immersion was analyzed by optical microscope and Scanning Electron Microscopy (SEM). X-Ray Diffraction (XRD) was used to study the phase structure present. The metallic ions in the artificial saliva were analyzed after the corrosion test by Absorption Spectrophotometer (AAS). Electrochemical Measurements by polarization experiments were performed to study the corrosion resistance, the main results obtained were expressed in terms of the corrosion potentials (Ecorr) and corrosion current density (icorr) in addition to measure the Tafel slops by Tafel extrapolation method, and also cyclic polarization are used in artificial saliva solution. The results of galvanic corrosion show that the Co-Cr-Mo alloy had localized corrosion in artificial saliva at 37+1ºC.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2331
2339
https://etj.uotechnology.edu.iq/article_99987_7a83f7ead04ec59c8445591e16e506c8.pdf
dx.doi.org/10.30684/etj.32.10A.1
Speech Recognition Based Microcontroller for Wheelchair Movement
Mohammed
E. Safi
author
Eyad
I. Abass
author
text
article
2014
eng
This paper introduced an approach to design and implement a control system for the movement of wheelchair by means of the human voice for paralyzed patients. In this paper, the Mel-Frequency Cepstral Coefficient (MFCC) technique is used as feature extraction with Dynamic Time Warping (DTW) for features matching. The output of the system is used to control the movement of the wheelchair through an interface between notebook and microcontroller. The experimental results showed that the proposed methods gave a recognition rate 100% of the already trained speakers with environment noise reach to 66dB. The test was conducted at different sound levels of the surrounding environment (53 to 73) dB as measured by Sound Level Meter (SLM).
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2340
2350
https://etj.uotechnology.edu.iq/article_99995_5b28a8d08c7d786b5620f0aca99fcdb8.pdf
dx.doi.org/10.30684/etj.32.10A.2
Influence of Acidic and Salt Media on The Corrosion Behavior of Aluminum Matrix Composites Reinforced by Al2O3 Particles
Niven
J.Abdal Kadir
author
Payman
S.Ahmed
author
Saja
Amer Abdul Majed
author
text
article
2014
eng
Corrosion behavior of pure Al and Al/ Al2O3 composite with five weight percent of Al2O3 particles (5,10,15,20 and 25) were investigated in 0.1M H2SO4 and 3.5 % NaCl solutions at room temperature. The composites were prepared by powder metallurgy and their corrosion behavior were evaluated by potentiostatic polarization and scan rate 3mV.sec-1. It's observed that pure Al/Al2O3 composites exhibited excellent corrosion resistance in NaCl medium than in the H2SO4 media. The pure aluminum exhibited slightly superior corrosion resistance than the composites in NaCl medium but the composites had better corrosion resistance in H2SO4 medium. Insulator Al2O3 particles are perceived to act as inert material and degrade the integrity of the protective oxide layer on the Al matrix. Al/Al2O3 composites have lower corrosion rate than pure aluminum in 0.1 M H2SO4, but increasing of wt% of alumina led to increase the corrosion rate. While in 3.5% NaCl solution can be seen that corrosion rate of pure aluminum less than that for composites. Generlly, For certain material, the corrosion rate in salt medium less than in acidic medium.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2351
2363
https://etj.uotechnology.edu.iq/article_99996_4df18b0d2903e8ade95571f9ba1d8583.pdf
dx.doi.org/10.30684/etj.32.10A.3
Investigate About the Iraqi Attapulgite Clay as a Mineral Admixture for Concrete
Kais
J. Frieh
author
Waleed
A. Abbas
author
Samer
H. Malik
author
text
article
2014
eng
Tremendous research efforts have been directed to investigate the possibility of using the Iraqi Attapulgite clay as a mineral admixture to improve some properties of concrete. To investigate about this clay as a pozzolan, many experimental work need to be done to find the suitable conditions of temperature and time of calcinations. To study the influence of calcinations temperature, different samples of Attapulgite were prepared. The samples were grinded to fineness 2109 m2/ kg , then burned to ( 550 , 600 , 650 , 700 , 750 , 775 and 800)˚C at 1/2 hour , respectively . According to the American Standard Specifications, the strength activity index was conducted on the cubic specimens with dimensions (50 * 50 * 50) mm. The results showed that the optimum calcinations temperature was 750 ˚C. The Attapulgite samples were prepared at ( 1/2 , 1 , 1 1/2 , 2 ) hours , respectively and the temperature was 750 ˚C , then strength activity index was conducted . The results showed that the optimum calcinations time was 1/2 hour.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2364
2375
https://etj.uotechnology.edu.iq/article_99997_bfe76d7395a8c92016a79534f4a70ab7.pdf
dx.doi.org/10.30684/etj.32.10A.4
Production of Micro and Nano Zirconia Particle by Pulsed Laser Ablation
Mohammed
Sellab Hamza
author
text
article
2014
eng
In this work, zerconia nano particles have been synthesis by using laser ablation in water. AFM measurement displayed that the particle size of Zerconia was 46nm and no other phases have been noticed. The root mean square of surface roughness becomes 0.743nm after laser ablation, while before that was 2.33nm. Granularity distribution chart observed that the particle size distribution of Zerconia before laser ablation was (100-400) nm, while after that become (20-80) nm .The microstructure investigation of zerconia nano particle was carried out by using SEM.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2376
2385
https://etj.uotechnology.edu.iq/article_99998_9e1adbdbdbfe67c027e03b209f3c70cb.pdf
dx.doi.org/10.30684/etj.32.10A.5
Effect of Surface Roughness and Shot Peening Treatments on The Mechanical Properties of Aluminum Alloy 2024 – T4
Alalkawi
H. J. M
author
Ameer
Tofan Shafiq
author
Mohammed
khalouk al-azzawi
author
text
article
2014
eng
The objective of the present paper is to investigate the effect of surface roughness on mechanical properties of aluminum alloy 2024-T4. This paper describes the effect of surface roughness at values of ( 0.1 , 3.5 , 8 ) μm on hardness and yield strength and also estimate the effect of shot peening on the yield strength at period time of ( 5 , 10 , 15 , 20 , 25 ) min. The obtained results show that the low roughness improved the mechanical properties by 15.7% and also the low roughness is better than the shot peening treatments by 5.3% because the low roughness make surface more coherent. Empirical equations are formulated based on the experimental results to evaluate the yield strength with the surface roughness and the hardness.Sy= 394.3 ( Ra + 1.35 ) -0.1356 Sy = 1 / 2.2227(10)-2 - 1.32(10)-4 HV
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2386
2393
https://etj.uotechnology.edu.iq/article_99999_1e3e945f624981a258fabc3aca12799d.pdf
dx.doi.org/10.30684/etj.32.10A.6
Behavior of Corbels Strengthened with Carbon Fiber Reinforced Polymers (CFRP) – Numerical Study
Sameh
Badry Tobeia
author
text
article
2014
eng
In this paper, a numerical modeling performed to study the effect of carbon fiber reinforced polymers (CFRP) as a shear strengthening of corbels. In this study a theoretical simulation is achieved with reinforced concrete corbels, several CFRP strengthening positions has been studied with different shear span – effective depth ratio (a/d) of (0.5,0.6&0.7). The numerical model, by using program (ANSYS 12.1) verified by compare its results with the experimental results. It was found that the position and the amount of (CFRP) as well as the vary of (a/d) ratio, have a great effects on the ultimate load capacity of corbels. Where, the ultimate load capacity increase as the amount of (CFRP) increased in certain positions of corbels, with regards the vary in (a/d) ratio.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2394
2407
https://etj.uotechnology.edu.iq/article_100000_bb6c8de0ef3889332531b88d47e4f56c.pdf
dx.doi.org/10.30684/etj.32.10A.7
Studying Soil Undrained Shear strength Due to Driving Piles Using Seismic Cross-Hole Technique
Hussein
H. Karim
author
Mahmoud
R. AL-Qaissy
author
Wisam
Rahi Hasan
author
text
article
2014
eng
The study is intended for geotechnical engineers who deal with the construction of deep foundations using driving piles with the implementation of seismic cross-hole technique to estimate the accompanying increase (or decrease) in soil shear strength. The study concluded that there is a direct relation between the increases in soil undrained shear strength with yield stress ratio and reverse relation with moisture water content and void ratio. The increase in undrained shear strength is observed in the clay soil layer at 3-5 m in depth with low moisture content and void ratio due to the effect of time. While at depth of 1-3 m, the reverse was noticed, this decrease is attributed to the upward displacement of the soil due to shear force from driven pile and then leading to increase the soil moisture content and void ratio. The study also concluded that an increase in undrained shear strength and yield stress ratio causing a decrease in void ratio and moisture content due to the effect of aging factor. The present results have provided good overall views of the shear strength increases and their distributions and the estimated values are also of the right sizes.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2408
2428
https://etj.uotechnology.edu.iq/article_100001_9220aaea4b142da8c8175bb24bf497fc.pdf
dx.doi.org/10.30684/etj.32.10A.8
Numerical Analysis of Machine Foundation Resting Saturated Sandy Soil
Mohammed
Y. Fattah
author
Nahla
M. Salim
author
Wourood
T. Al-Shammary
author
text
article
2014
eng
The behavior of machine foundation on saturated porous medium can be considered as a complicated geotechnical problem due to nature of dynamic loads and plasticity of soil which make the analysis and design of foundation subjected to dynamic loads more complex. The main criteria for safe performance of machine foundations subjected to dynamic loads are to control excessive displacements. In this paper, a dynamic analysis of strip machine foundation with multiple thicknesses is placed at the middle of the top surface of saturated sand with different states (i.e. loose, medium and dense), and vertical harmonic excitation is carried out and building up of the excess pore water pressure. The dynamic analysis is performed numerically by using finite element software, PLAXIS 2D. The soil is assumed as elastic perfectly plastic material obeys Mohr-Coulomb yield criterion. A parametric study is carried out to evaluate the dependency of machine foundation on various parameters including the amplitude and the frequency of the dynamic load. The dynamic response (displacement and excess pore water pressure) generally increases with increasing of loading amplitude, but the displacement and excess pore water pressure versus frequency are not smooth and exhibit undulations (peaks and troughs).
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2429
2453
https://etj.uotechnology.edu.iq/article_100002_5387508b73c35c79062007f06ecf17b5.pdf
dx.doi.org/10.30684/etj.32.10A.9
Effect of Compaction Methods on the Properties of Roller Compacted Concrete
Hisham
Khalid Ahmed
author
Azal
Thair Abdulrazzak
author
text
article
2014
eng
Roller compacted concrete (RCC) is a technology characterized mainly use of roller for compaction. This construction method permits considerable reduction in costs and construction time of dams and roads. The main aim of this work is to investigate the influence of compaction methods on the properties of RCC. the experimental program included preparing cylindrical specimens with (diameter of 150 mm by height of 300 mm) for measuring the compressive strength, splitting tensile strength and absorption. And it also includes prism specimens with (100*100*400) mm for measuring the modulus of rupture. These specimens were compacted by using different compaction methods, dynamicly (modified proctor hammer compaction (CBR test), vibrator table, and vibrator table with CBR test) and statically (compacting pressure (compacting pressure 10 MPa, 15 MPa and 20 MPa). Results show that the compaction methods have a noticeable effect on the properties of RCC. The results also indicated that using vibrator table with CBR show an increase in the compressive strength, splitting tensile strength and modulus of rupture by 23%, 14% and 13%, respectively as compared with compacted by vibrator table only. The results also show that using compacting pressure 20 MPa show an increase in the compressive strength, splitting tensile strength and modulus of rupture by 31%, 27%, and 39%, respectively as compared with that made by compacting pressure 10 MPa.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2454
2464
https://etj.uotechnology.edu.iq/article_100003_0c10358455afa22d5efbb92ff8c70b9b.pdf
dx.doi.org/10.30684/etj.32.10A.10
Evaporation Estimation Using Adaptive Neuro-Fuzzy Inference System and Linear Regression
Ali
H. Al-Aboodi
author
text
article
2014
eng
Evaporation is important for water planning, management and hydrological practices, and it plays an influential role in the management and development of water resources. This study demonstrates the application of two different models, adaptive neuro-fuzzy inference system (ANFIS), and linear regression (LR) models for estimating monthly pan evaporation in Basrah City, south of Iraq. In the first part of this study, the ANFIS model is used twice, in the first one, the temperature is used as input data only, and in the second one, the temperature and relative humidity are used as input data for predicting the evaporation. A verification test is added to check the model correctness by matching the calculated evaporation with the once observed in Basrah city for the period (1980-2009). In the second part of the study, the results obtained by ANFIS models are compared with results of linear regression model. The comparison reveals that the ANFIS models give better accuracy in estimating monthly pan evaporation than the linear regression model. The accuracy is improved about 5% in correlation coefficient (R) and determination coefficient (R2). The results proved that monthly pan evaporation could be successfully estimated through the use of ANFIS models.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2465
2474
https://etj.uotechnology.edu.iq/article_100004_5c6cb9bdcb492261f3773f6bb7e61196.pdf
dx.doi.org/10.30684/etj.32.10A.11
Effect of Tunneling in Cohesive Soils on Existing Structures
Ameer
Abdullah Ahmed
author
text
article
2014
eng
The present work is focused on the influence of shallow tunneling on the settlement of existed two storey building supported on different soil properties ranging from medium to stiff clayey soil that having young modules of "50,75 and 100 MPa". Eight locations of the tunnel center "diameter = 4m" were fixed below the building strip footing "width = 2m" at different depths and locations to determine the critical location of the tunnel at each depth. A total of 24 Finite element CAD "ANSYS" solutions were performed on the eight locations for each of the three types of soil. The results of the FEM analysis show that the effect of tunneling was to increase the surface settlement and creating differential settlement at the different locations and the critical location of the tunnel was when the tunnel center is located below the center line of the footing at both depths.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2475
2490
https://etj.uotechnology.edu.iq/article_100005_b895fd4a3d6e158c6f5cbef17268a884.pdf
dx.doi.org/10.30684/etj.32.10A.12
Direct Shear Behavior of Carbon Fiber Reinforced Self- Compacting Concrete
Kaiss
F. Sarsam
author
Tareq
S. Al-Attar
author
Ghzwan
Ghanim Jumah
author
text
article
2014
eng
This paperrepresents an experimental and statistical investigation for the behavior of connectionpoints produced by using self-compacting concrete and subjected to direct shear. The investigation also includes the effect of carbon fiber inclusion as reinforcement on self-compacting concrete (SCC) behavior in direct shear. This study gives results of sixteen push-off or direct shear specimens in four groups. Variations include volume fraction for carbon fiber (V_f= 0.00, 0.50, 0.75 and 1.00) % for every percentage change in the steel reinforcement. The steel reinforcement parameter ρ_vf f_y values are (0.00, 2.66, 5.33 and 7.99) MPa(where ρ_vf varies from 0.00 to 0.0173 and f_y=585.7MPa) . The main material properties studied include compressive strength, splitting tensile strength and modulus of rupture. Measurements of deformations were made throughout testing of shear specimens. The dimension of the shear plane in the push-off specimenswas 170x185 mm. The shear reinforcement was normal to the shear plane. Specimens were cast by using SCC which is a type of high performance concreteand reinforced with carbon fiber. This work aims to investigate the direct shear behavior of SCC with or without carbon fiber at constant water to cementitious materials ratio of 0.3 by weight. It is found that using carbon fiber increased the direct shear strength. However, carbon fiber alone (without reinforcement) leads to brittle failure. In contrast, adding rebars leads to higher strain and more ductile behavior-increased shear capacity is obtained when higher steel quantity is used. The aim of adding carbon fibers was the increase of the horizontal strain (displacement). It was found that the optimum percentage of volume fraction was 0.75 % for fresh and hardened concrete. In addition, the effects of carbon fiber on compressive strength of SCC lead to a drop in compressive strength (f_c^') compared with reference specimens. This drop in f_c^' was 2.39, 8.38 and 13.58% for V_f=0.50, 0.75 and 1.00%, respectively. In contrast, the splitting tensile strength increased by 3.34, 31.2 and 18.2 as compared with the cylinder strength without carbon fibers atV_f equal to0.50, 0.75 and 1.00% respectively. The modulus of rupture increased by [11.9, 21.99 and 13.83%] as compared with SCC without carbon fibers at〖 V〗_f equal to 0.50, 0.75 and 1.00% respectively. Based on push-off tests results for this work and those available in the literature, two statisticalmodels have been established using regression analysis. Four variables f_c^',f_ct,ρ_vf f_y and V_f, were included in these models. Both models showed good representation according to their coefficients of variation (COV)values. Verification of the models were done by using 273 observations from literature and the present work.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2491
2513
https://etj.uotechnology.edu.iq/article_100006_480ba851bcd2dcfb0090405a5f6084b3.pdf
dx.doi.org/10.30684/etj.32.10A.13
Heat Transfer Enhancement in a Tube Fitted with Nozzle-Turbulators, Perforated Nozzle-Turbulators with Different hole shap
Akeel
Abdullah Mohammed
author
Bashar
Ali Mohammed
author
Raheem
Jewi Muhee
author
text
article
2014
eng
The present study is to investigate experimentally the enhancement of forced convection heat transfer by means of passive techniques for a turbulent air flow through an Aluminum test tube. Reynolds number range is from 6000 to 13500 with boundary conditions of constant heat flux. The augmentation process is done by using divergent Nozzle-Turbulator arrangement with and without perforation models (triangle holes, square holes, and circle holes). The experimental results at the same Reynolds number show that the divergent nozzle-turbulators without perforation provides the highest heat transfer rate 317% and highest friction factor 17 times over that of plain tube with a performance factor of (1.58). On the other hand the perforated Nozzle-Turbulators with triangle holes gave a thermal performance factor of (1.7) which is the highest thermal performance factor among all other perforated and non perforated nozzle turbulators used in the present study
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2514
2527
https://etj.uotechnology.edu.iq/article_100007_33240a7726a8b897eb70c927435ad44f.pdf
dx.doi.org/10.30684/etj.32.10A.14
Study and Comparison The Performance of Sensorless Control of PMSM Drive System
Majid
K. Al-Khatat
author
Ghphran
Taha Ahmed Abd
author
text
article
2014
eng
Field oriented control space vector pulse width modulation (FOC- SVPWM) is one of the effective and modern methods for speed control of Permanent magnet synchronous motor (PMSM). A mathematical model and theoretical analysis of (FOC-SVPWM) driven a PMSM are presented .In this work, a control methods for PMSM using Model reference adaptive system (MRAS) are utilized to compare the performance behavior under conventional PI, Fuzzy PI, and Particle swarm optimization (PSO) control methods. Extensive simulation results are presented using MATLAB/SIMULINK program which including (SVPWM generation, inverter, PMSM, the reference frame transformation and different PI controllers) as well as the estimation method using MRAS. This work presents a comparative study to investigate the performance of PMSM based on MRAS when different load conditions are applied to PMSM and under three different controllers: the first controller is the Proportional-Integral (PI) based on classical trial and error method, the second controller is PI controller based on PSO technique for optimal gains tuning and thus improve the performance of the system. The obtained results show that an improvement in motor performance when using PI-PSO compared to classical PI controller. The third controller is Fuzzy-PI with scaling factor (gains) tuned by PSO technique. This method can improve the performance of the system compared with PI-PSO in terms of reducing steady state error, rising time, overshoot and smoother response to make this controller more robust to variation in load other than the rest motor controllers.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2528
2547
https://etj.uotechnology.edu.iq/article_100008_79369b9e7ce44c80c99f76f59b1091e2.pdf
dx.doi.org/10.30684/etj.32.10A.15
The Use of New Techniques in The Management of Waste Plastic by Reuse it in The Asphalt Mix
Falak
O. Abas
author
Raghad
U. Abass
author
Enas
.A .A
author
text
article
2014
eng
The quantity and type of waste being generated is growing at enormous rate. The plastic waste produced particularly in form of bags, Plates, Containers, being non-degradable and with limited recycling options poses disposal problem. An academic research aimed at probable use of waste plastic in pavement structure so as to come up with an ultimate safe disposal together with improvement in the performance of asphalt mix of road through better mix design was under taken. Preliminary investigations have indicate of RPWA (from 1.2 in (1.5 cm) to No. 200 sieve ( 0.075 cm) , in surface mix design when utilized up to (5% to 15%) by weight substitution, through the use of Box-Wilson design program in order to give an optimum condition, time of reaction, and weight percent of substitution replacement aggregate in asphalt mix. The above following variables were studied temperatures (109-206) c , time (20-60) min and weight at waste substitution (5-15) % wt. respectively. The optimum conditions were: were 172 oc, 40 min, and 10% wt RPWA. The effects of experimental variables on the properties of improved asphalt mix were studied using the Box-Wilson technique of experimental design and useful relationships could be attained. Which improved these optimum conditions give high stability of Marshall Test and low distortion with acceptable low constant wet density and uneffect dry density with these condition with high resistance to chemical solutions exposure? It is envisaged that use of RPWA in the conventional asphalt hot mix design likely to improve the surface asphalt mix performance with sustainable solution for the disposal of plastic waste.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2548
2567
https://etj.uotechnology.edu.iq/article_100009_b88d078ca49d18d7385e89267995708b.pdf
dx.doi.org/10.30684/etj.32.10A.16
Effect of Thermally Sprayed Ceramic Coating on Properties of Low Alloy Steel
Fadhil
A. Chyad
author
Abdalkalaq
F. Hamood
author
Lamees
S. Faiq
author
text
article
2014
eng
Thermal spraying technique was employed for coating low alloy steel specimens that have been used in a derrick oil well frames. Two types of ceramic materials were used as a coating material and two groups of steel samples were prepared for coating process. The first group was coated by zirconia while the second group was coated by alumina. Ni-Al composite powder was used forbonding the coating material on the substrate surface of the steel specimens. The hardness, adhesion strength of the coating layers as well as wear rateswere studied for the two steel group samples and compared with as received steel. The results showed an increase in the mechanical properties with a decrease in wear rate values for coated samples as compared to those of uncoated samples.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2568
2575
https://etj.uotechnology.edu.iq/article_100010_eb886d49d295a641b4989565aced4cd8.pdf
dx.doi.org/10.30684/etj.32.10A.17
Effect of Different Refrigerant Injection Techniques on Heat Pumpcycle Performance
Abdual
Hadi N. Khalifa
author
Johain
j. faraj
author
Anmar
Adnan
author
text
article
2014
eng
Refrigerant injection techniques are considered as modifications to vapor compression refrigeration systems to improve the performance of these systems when operating at high or low ambient temperatures. In this study a liquid and vapor refrigerant injections were implemented using heat exchangers arrangement. An investigation to the effects of these techniques on the performance of refrigeration cycle was conducted. A decrease in discharge temperature was obtained using hybrid injection cycles from 20% to 19% when the ambient temperature varies from 14C to 8C. Also the decrease in pressure ratio varied from 24% at an ambient temperature of 14C to 18% at 8C. The enhancement in performance factor varied from 35% at 14 C to 28% at 8 C.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
2576
2586
https://etj.uotechnology.edu.iq/article_100011_f2fe1f35740939a00e0dc14b71f4c779.pdf
dx.doi.org/10.30684/etj.32.10A.18
The Influence of The Hydraulic Pumps Design Characteristics and Temperature of Mineral Oil on The Stability of Actuator
Abdul
Karim Swadi Saleh
author
Farid
Abou Hamed
author
Jafer
Mehdi Hasan
author
text
article
2014
eng
Much research dealt with the problem in the pulsation of hydraulic pumps, studies, research and literature for vibration did not interfere with the effect of the medium which make vibrations and effect of temperature on the medium (the indirect effect on mechanical vibration). In this research a practical correlation between pulsation of pumps and temperature, pressure and vibration will be developed. To achieve this goal the hydraulic system was designed and implemented to deduce the effect of the internal design of the three main hydraulic pumps, gear pump, vane pump and piston pump, in conjunction with the high temperature of the mineral oil on the vibration generated by the piston arm and the stability of the actuator. Vibration Meter device used to indicate the vibration at the tip of the arm plunger for hydraulic piston and uploaded with a variable load (spring), as well as a computer-aided reading was recorded. It was shown that the interior design of the pumps had an effective influence on the values of acceleration and speed of vibration, even if convergence frequency pulse outside of the slot pressure pumps. This effect cannot be separated from the oil temperature which affect the increasing values of acceleration and speed of vibration recorded on the tip of the plunger arm (performance of the piston) also the pressure has an effect on the values of acceleration and speed of vibration . The temperature of the mineral oil had a strong influence on the performance of hydraulic systems, at the resonance condition.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
324
337
https://etj.uotechnology.edu.iq/article_100012_955c5905c34a2c046d86ab424c79bac9.pdf
dx.doi.org/10.30684/etj.32.10A.19
Excessiveness Concept in Architecture
Ali
Mohsen Jaafar Al-kafaji
author
Zainab
Ismael Abd Al-kadum AlRubaiey
author
text
article
2014
eng
The concept of excessive emerged as one of the concepts of contemporary architecture. This quantum of information led us to neediness searching for literature and previous studies on this concept and discover the knowledge gap in it, that resulted research problem which is (the lack of a comprehensive framework describes to the concept of excessive ,aspects associated with it, and the formula and the levels achieved in contemporary architecture), so identified targets search For the definition of this concept and everything related by the goal of search have been associated with: formulation of excessiveness theoretical framework in thought, language, and science to start studying the intellectual and scientific foundations in architecture in general. particularly the goal concentrates in effort to reached the what the excessive output is. and make the excessiveness theoretical framework and its generated technology. as for the taken approach in this search first it has been study the intellectual aspects then it has been follow-up his appearance in the architectural outputs. after that it goes to theoretical framework and determination the vocabulary from it. then it has been select the measures of application and finally puts the results and its conclusions.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
32
v.
10
no.
2014
338
352
https://etj.uotechnology.edu.iq/article_100013_8aa5b495d8f6bd4c15670a149b52bfd0.pdf
dx.doi.org/10.30684/etj.32.10A.20