Engineering and Technology Journal

This paper reports research conducted into classification of red blood cells using multi-category digital learning networks. It is an effective solution for providing healthcare with reduced cost, especially for the rural and far away patients. Digital learning network offer an alternative approach to neural network design. It often referred as( RAM-Based Architectures) , or ( Weightless Neural Networks), since their neurons can be implemented by RAM node that usually input and output binary values with no weight between nodes. The system presented in this paper fulfills the requirements of simplicity and efficiency making it attractive to practical use in present day for industrial and medical environments. Many parameters have been investigated in detail which affects the recognition rate. These parameters are presented to allow the system to be optimized, giving an increase in the performance of the system. Modification method of Feedback Digital Learning Network, which is an improving process of Digital Learning Network, has been implemented. The obtained results showed that high performance can be achieved (96.6% as correct, 2.2% as reject, and 1.1% as error), providing evidence of the validity of the proposed technique.

A simple computational model is established to simulate a capacitor discharge process through a spark gap. The model constitutes of three intervals, the first one is concerned with charging the capacitor by a D.C. voltage source, where the voltage across the capacitor raisesto a certain critical valueregarded as the breakdown voltage of the spark gap. The second interval describes the gap breakdown where the resistance of the ionized gas in the gap decreases very sharply as a result of heating the plasma by the electrical current. This interval is denoted as the resistive phase of the discharge. The third interval describes the discharge through the previously heated plasma in the gap;for this interval the plasma resistance is assumed tohave a constant value which is considered as the minimum value obtained at the end of the previous interval (the resistive phase interval). The temporal evolution curves obtained from the model exhibit reasonable trends that conform to the physical situation under study. Also, the comparison made with published data shows an acceptable agreement. The model is employed to perform a parametric comparison to examine the rule of the gap parameters on the voltage and current evolution curves.

This paper proposes a design model of InAs QD laser diode structure, the dimensions of the proposed model have an active region of length 800µm, width 12µm, and a height of 375nm. The proposed model of QD is disk shaped, its height is 2nm and diameter is 14nm. The QDs surface density per layer is 7×1012 cm-2, number of QDs layers are 5 layers, wetting layer thickness is 1nm and barrier thickness is 90nm.
The evaluation of the proposed model is based on rate equations model.The InAs/GaAs QD lasers are capable of working at a very low threshold current, which is very important for the development of optical fiber communication systems.Modulation characteristics of InAs/GaAs quantum dot (QD) lasers of 1.3µm wavelength have been carefully studied at various bias currents and K-factor, the (-3 dB) bandwidth is improved at first as increasing the injected current, in addition, at large injected current, maximum value of the bandwidth is limited by K-factor, and the K-factor is mainly determined by the photon lifetime and the effective capture time, the K-factor can be minimized by choosing an optimum photon lifetime.
The results show that the QD laser diode has a lower threshold current (2mA),the threshold current density (20A/cm2 ), bias voltage 0.92V, while output optical power has the range of (0-25mW), the slope efficiency is 0.25W/A. The highest relaxation oscillation frequency at room temperature is 10.18 GHz, corresponding to a modulation bandwidth of 3 GHz due to the small damping factor. Using these parameters, the maximum modulation bandwidth (f-3dBmax) is estimated as 15.56 GHz.

Semiconductor-based metal oxide gas detector of five mixed Z:S from zinc chloride salt (0,25,50,75,100%) ratios with tin chloride salt, were fabricated on glass substrate by a spray pyrolysis technique with thickness were about ( 0.2 ±0.05 µm) using water soluble as precursors at a substrate temperature 500 Cº±5, 0.05 M ,and their gas sensing properties toward (CO2 , NO2 and SO2 gas at different concentration (10,100,1000 ppm) in air were investigated at room temperature which related with the petroleum industry.
Furthermore structural and morphology properties was inspecting. Experimental results show that the mixing ratio affect the composition of formative oxides (ZnO,Zn2SnO4,Zn2SnO4+ZnSnO3,ZnSnO3, SnO2) ratios mentioned in the above respectively, and related with the sensitivity of the tested oxidation gases.

This paper presents an experimental investigation on the flexural behavior of reinforced concrete slabs under one way bending. Sixteen simply supported slabs of dimensions 1000mm×450mm×50 or 70mm were manufactured and tested. Twelve slabs were constructed using self compacting concrete (SCC) and four using conventional concrete (CC). Four variables were adopted to investigate slabs behavior: type of concrete (CC or SCC), longitudinal steel ratio (ρ), slab thickness (t) and steel fiber ratio (Vf). Test results showed that slab thickness (t) was the most effective factor in increasing ultimate load (Pu) of SCC slabs (up to 111%) as compared to the longitudinal steel ratio (ρ) and steel fiber ratio (Vf) with ΔPu up to 64% and 75%, respectively. Results also showed that using steel fiber in SCC up to 0.8% reduces its filling and passing abilities but it still satisfies the requirements of SCC specifications. In contrast, steel fiber increase compressive strength and modulus of rupture of SCC up to 10% and 60%, respectively.

Line balancing problems are well-knownapplicationsof industrial engineering in Academic Universities. Effective Line Balancing forms the core of every successful organization as strive to increase productivity without incurring unnecessary costs. Factors contributing to high costs such as excessive overtime and work force, high level of inventory and idle time are all parts of the results of poor line balancing.
Iraqi industries suffer from a strong shockdue to high competitive products in the market associated with less cost than can be offered.To survive these industries from collapse and bankruptcy, they need to utilize theirsources effectively and efficiently to improve the productivity and reduce loses.One way to achieve that is to adopt the scientific approaches. The researchhasbeen appliedin one of the important industries based on Baghdad i.e.light IndustrialCompany assembling Gas Cooker. The assembly line left unbalancedany methodology for balancing the assembly line was not implemented on the assembly line of the company. to implement a scientific methodology production of 20 units/day was employed.When the efficiency of the assembly line analysis found low as 50% from the available efficiency and combined with low productivity.The suggested methodology shows that the production rate can been doubled with same capabilities of resources available and efficiency increased to 92%. Moreover, about 50% reduction in idle time and well-organized of the assembly line by creating 9 workstations. This effect is in addition to increasing productivity , the human factor will be affected positively by raising motivatethe morale from one side and distribute the load evenly among them from the other side .

There is much work currently in the field of renewable energy, particularly, solar energy to replace the traditional energy sources. In this paper, a solar charge control system has been designed with voltages of 24 V and 12 V and current capacity of 220 A. The design procedure is firstly set-up by adjusting the input voltage delivered from solar cells during the period (7 a.m.–5 p.m.) for maximum sun rise.
To assess the robustness of the designed circuit, the circuit has been simulated under different input voltages and external load conditions. The first test is verified by changing the input voltage supplied from the PV solar panel with the same voltage change during the test period. The results showed that the output voltage has remained at constant level. The other test is performed by changing the output load value such that it reaches approximately the load of batteries. It has shown that no change in total currents occurs. This could prove that the design technique give both stable and robust performance. Moreover, the designed charge controller can successfully deliver a charge power of 2KW. This power is considerably high when compared with other circuits.
The design of the charge control system is based on simulated results and it has been verified using PSpice.

Chemical machining is a well-known nontraditional machining process and is the controlled chemical dissolution of the machined work piece material by contact with a strong acidic or alkaline chemical reagent. It is also called as chemical etching. The present work is aimed at studying the effect of machining time, machining temperature, etching solution concentration on the surface finish of stainless steel 304 using mixed of acids (HCL+HNO3+HF+ H2SO4+H2O). Alloy samples are of (33×33×6) mm dimensions. Three machining temperatures (45, 50 and 55 ºC) for each of which three machining times (3, 6, and 9 min) were used as machining conditions. Surface roughness increases with the machining temperature and machining time. An assessment of CHM was achieved by empirical models for selecting the appropriate machining conditions of the required surface finish. The models were designed based on multiple regression method via Mtb 16 software.

In this study, the influence of bothheat treatment and cold working (rolling) on the tensile properties andhardness of6061 aluminum alloy sheets was investigated. The solution heat treatment is first performed at about 520°C 1 hr followed by rolling to(40% and 60%). Artificial aging is obtained by heating to about 180 °C for 1/2hr and 2 hr.Theexperimental work has revealed that when two strengthening mechanism(cold work and aging)are combined, the values of the mechanical properties are come up.Increasing the aging time from ½ hrto 2hr with redaction in area was causing increase in the values of the strength and hardness and dropping the elongation. In the other hand, increasing the redaction in area from (40%) to (60%) with aging was rising the value of the strength and hardness and dropping the elongation. The changes in mechanical properties were discussed as a result of increasing the dislocation density(result of rolling) and formation of precipitation(effect of aging) which are interface with the motion of dislocation and causes hindering of dislocation.

This paperattempted to study the induced surface residual stressesduethe effect of Electrical discharge machining (EDM) input parameters, (the pulse current,the pulse-on time and the type of electrode).The work includedthe use of two types of electrode, the copper and graphite as well as using or without using the graphite powder mixing with the kerosene dielectric (PMEDM) for machining AISI D2 dies steel. The response surface methodology (RSM) was usedfor design the experimental work matrices. The analysis of variance (ANOVA) was used, and models were builtto predict the surface residual stresses.The obtained results showed that the minimum tensile surface residual stresses obtained when using the copper electrodeswith pulse current (22 A) and pulse on duration (40 µs) when working with kerosene dielectric alone and (8 A) with (120 µs) when working with graphite powder mixing. The results concluded that the using of graphite electrodes and kerosene dielectric alone or with powder mixing induced minimum residual stresses with pulse current (22 A) and pulse on duration (120 µs). The copper elec-trodes with kerosene dielectric and graphite powder mixing improved the induced tensile residual stresses by about (80 %) lower than when using kerosene dielectric alone and about (50%) lower than with graphite electrodes and the kerosene dielectric alone or with graphite mixing powder.

Radio-over-Fiber (RoF) system refers to the radio signals which are modulated with optical signal and transmitted over optical fiber link from Central Office (CO) to the Remote Nodes (RNs).In this paper, RoF system with Wavelength Division Multiplexing (WDM) and Subcarrier Multiplexing (SCM) techniques, has been designed and simulated with different modulation schemes (such as: 4-QAM-OFDM, 16-QAM-OFDM and 64-QAM-OFDM schemes) to increase the capacity of the system by 20×8 Gbps data rate. The simulation results show that the SCM-WDM-RoF with 16-QAM-OFDM scheme gives better performancewith symbol error rate (SER) equal to 10-9, and reduces the power consumption compared with SCM-WDM-RoF system with other modulation schemes which have been used in this work. The software package "Optisystem version 12" has been used to simulate this system.

Laboratory tests were conducted to evaluate the quality of drinking water on some water treatment plants in Baghdad (AlKarkh, Shark Dijla, AlWathba, and Alkramh), the samples taken from raw (Tigris River) and treated water. The measurements of some physical and chemical properties taken every month and for eight years in order to evaluatethe drinking water quality and efficiency of these plants. The quality of drinking water was calculated byusing Canadian model index (Canadian Council of Ministers of the Environment) in water quality evaluation, as contributed thirteen variables in the index calculation: the temperature of the water, turbidity, pH, total hardness (as CaCO3), magnesium, calcium, sulfate, iron, fluoride, Nitrate, chloride, color and conductivity. The sampleswere taken from the treatedwater that outside from the plant from 2005 to 2013. The study showed that the range of water quality index for raw water is (51-57) and can be classified as a bad water and needs advanced treatment, while the water quality index of treated water was (86, 81,80,80) for (AlKarkh, Shark Dijla, AlWathba andAlkramh) respectively. The water quality index of treated water of (AlKarkh, Shark Dijla, AlWathba and Alkramh) can be classified as Category II ( good).

Nowadays, CNC machines have high importance in manufacturing factories and workshops due to its high accuracy and flexibility. Unfortunately it still cannot ensure the quality of machined products. The trend towards automation in machining has been driven by the need to maintain high product quality with improving production rate. These improvements can be possible by monitoring and control of machining process, in this research a new algorithm is introduced for the direct measurement of cutting tool wear by vision system on the basis of edge detection and morphological operations for the captured images. The results showed the efficiency of the proposed method for online monitoring of the tool condition.

In this research three groups of polymer blends have been prepared First groupincluded (Polystyrene (PS): Low density polyethylene (LDPE))While the Second group(included Polystyrene (PS): Polypropylene (PP)) and Third groups include (Polystyrene (PS): Poly methel methacrylate(PMMA)) are prepared in different ratios by melt blending technique which was carried out using a double screw extruder. The tensile, flexural, impact and hardness test are used to study mechanical propertiesof polymer blends. The results from this work show that the impact properties for blends system increases with increases each of (LDPE, PP and PMMA) content in polymer blends of (PS: LDPE), (PS: PP) and (PS: PMMA). The elongation property increases with increases LDPE and PP but decreases when adding PMMA in polymer blend.

Aerobic granular activated sludge is an attractive and promising process for intensive and high-rate biological nutrient removal (BNR) and secondary clarification in a single reactor.This work reportsthe performance of aerobic granular sludge sequential batch reactor (SBR) seeded with flocculated activated sludge collected from an Iraqi municipal wastewater treatment plant, using synthetic wastewater. The conditions under which the successful cultivation of aerobic granular sludge was done are as follows: influent chemical oxygen demand (COD) was 1100 mg/l, volumetric exchange rate was 50%, aeration time was 10 hr, anoxic time was 2 hr aerationand sludge settling time was about 0.5 min. After 90 days, the dominant granules size was 1.5-3.5 mm. The granules became regular in shape with smooth surface, sharp boundaries and compact in structure. The biomass concentration in the reactor in terms of MLSS was 4100 mg/l. Sludge volume index (SVI) was 60 ml/g. High syntheticCOD removal and simultaneous nitrification and denitrification during aerobic phase was observed. Subjection of themature granules to a low COD municipal wastewater the activity of the granules was significantly reduced.

This study was carried out to investigate the physical and mechanical properties of mortar cement produced from Carrot Powder (CP) . To do this, 4 mortar cement specimens were formed by changing the weight of CP and cement. Increasing ratio of CP weight ratio affected the compressive strength, impact, hardness. As for the bending ,water absorption and fracture toughness decreased and were affected positively. It was concluded that CP might be used in mortar cement production to replace the cement in certain ratio to make them profitable and lessen their adverse effects on the environment.

The new concrete types like steel fibers concrete have intensively investigated during the last decades. Although, many researches had focused on the mechanical properties of steel fibers concrete, few researches had concern with its durability with regards to freezing and thawing cycles. This research is aimed to study the behavior of steel fibers concrete under repeated cycles of freezing and thawing. Four different mixes has been investigated, three with steel fiber content of 0%, 0.5%, 1% and 1.25% as volume fraction of total mix in addition to reference mix without fiber. 60 specimens were tested according to ASTM-C666-97. 90 cycles of freezing and thawing were preformed after 28 days of curing. The compressive strength, flexural strength, Pulls velocity and durability factor, weight change and total absorption were tested after 0, 30, 60 & 90 cycles.
The results show that steel fibers concrete possess an acceptable freezing and thawing resistance. However, a considerable redetection in compressive strength and flexural strength was recorded with the increment of exposure to freezing and thawing cycles. The results also indicate a slight decrease in the specimens’ weight with the increase in number of freezing & thawing cycles without any deterioration in the apparent look of specimens. All mixes show close results for total absorption at all stage of the test.

In this research the maintenance activities isinvestigated for lube oil factory (3) as this factory is the newest and largest in its production capacity compared to lube oil factories (1) and (2)at Daura refineries.Data of different equipment’s failure are collected for ten consecutive months.
The frequency of breakdowns and type of maintenance were identified and analyzed employing certain statistical techniques are; Pie and Pareto charts. Results indicate that %95 of breakdowns for different equipment’s in lub oil factory 3 (pumps, heat-exchangers, compressors, docks, filters, furnaces and towers) are due to mechanical causes, and the rest are related to electrical causes. Pareto charts highlight that most frequent failuresfor pumps and exchangers followed by compressors and other equipment of lube oil factory 3.Types of maintenance classification shows that Pumps are dominating corrective maintenance activities in terms of frequency of occurrence. Although the frequency of breakdown in exchangers is the same as that for pumps, but these pumps suffer from both mechanical and electrical breakdowns. Equipment failures lead to many problems such as loss of production time, loss of material and lack of achieved production order. It is recommended to focus upon planned programmed maintenance and adopting decision support systems.

The paper describes an investigation for the thermal design of a fluidized bed cooler and prediction of heat transfer rate among the media categories. It is devoted to the thermal design of such equipment and their application in the industrial fields. It outlines the strategy for the fluidization heat transfer mode and its implementation in industry. The thermal design for fluidized bed cooler is used to furnish a complete design for a fluidized bed cooler of Sodium Bicarbonate. The total thermal load distribution between the air-solid and water-solid along the cooler is calculated according to the thermal equilibrium. The step by step technique was used to accomplish the thermal design of the fluidized bed cooler. It predicts the load, air, solid and water temperature along the trough. The thermal design for fluidized bed cooler revealed to the installation of a heat exchanger consists of (65) horizontal tubes with (33.4) mm diameter and (4) m length inside the bed trough.

The current experimental study is made to investigate the heat transfer characteristics and pressure losses for both impingement and impingement/effusion cooling systems.The experiments are carried out on a metal test plate.The numerical work is made to analyze the flow behavior in the test section. The benefit of introducing the present experimental method is the capability of investigating and analyzing the performance of both impingement and impingement/effusion cooling systems by the same test rig. The impinging jet device configurations are designed as inline round multi-hole arrays with jet to jet spacing of 4 jet hole diameter. The effusion holes configurations are inline round multi-hole arrays. Staggered arrangement between jet and effusion holes is maintained. The Jet Reynolds numbers (Re_j) of 5000 to 15000 and jet height to diameter ratio ( H⁄D ) of 1.5, 2.0, and 3.0 are maintained. For impingement/effusion case, the best wall cooling effectiveness is obtained at(H⁄D =2), and maximum increment in the wall cooling effectiveness over that of impingement case is 23% at (Re_j= 5000), 16 % at (Re_j= 7500), and 14% at (Re_j= 15000). Jet spacing in impingement case and blowing ratio in impingement/effusion case show an evident effect on the discharge coefficients.