@article { author = {GELANY, M. and ABOU-EL-ZAHAB, E.M and ABD -EL-NAEIM, M.}, title = {MICROCOMPUTER BASED SYSTEM FOR CONTROLLING REINFORCED CONCRETE STEEL CORROSION}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {1-23}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2002.70937}, abstract = {The contribution of this work is the design of microcomputer based system for measurement, monitoring and pulse width modulated power supply (PWM) as integrated control system with strong software suitable for different electrochemical control techniques of the reinforced concrete corrosion and repair locations. The combination of sacrificial (galvanic) and impressed current cathodic protection was laboratory tested with the proposed control system. The corrosion tendencies as measured by potential, are determined according to ASTM C876-87 half-cell method. In this work, the study of reinforced concrete steel corrosion under different conditions is presented. The behavior of Aluminum anode and its stability as a reference electrode was studied.}, keywords = {Reinforced concrete,steel corrosion,cathodic protection,sacrificial anode,Aluminum anode,concrete repair,~nicroprocessor controller}, url = {https://erjm.journals.ekb.eg/article_70937.html}, eprint = {https://erjm.journals.ekb.eg/article_70937_6769077f002585fdd9e9956cf2c5e497.pdf} } @article { author = {Mahfouz, F. M.}, title = {Natural Convection From an Elliptic Tube with Major Axis Vertical and with Uniform Surface Heat Flux}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {25-39}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2002.70944}, abstract = {The problem of natural convection from an elliptic tube with its major axis vertical and. i heated uniformly is investigated. The study is based on the solution of full governing equations without boundary layer simplifications. The study focuses on the effect of the I main controlling parameters on both flow and thermal fields. The controlling parameters ! are the modified Rayleigh number, Ra Prandtl number, Pr and axis ratio, Ar. The Ra is considered up to lo7 , the Pr is considered up to 10 while the axis ratio is varied from 0.05 (almost flat plate) to 0.998 ( almost circular cylinder). Results are presented for the local and average Nusselt numbers and local and mean surface temperatures. The study revealed that as Rayleigh number andlor Prandtl number increase the average Nusselt number increases, resulting in a decrease in mean surface temperature. On the other end, the study showed that the effect of axis ratio on the average Nusselt number is not significant with only smaller decrease in average Nusselt number as the axis ratio i increases. 5}, keywords = {Natural convection,Elliptic tube,Axis ratio,Rayleigh number,Prandtl number,Nusselt number}, url = {https://erjm.journals.ekb.eg/article_70944.html}, eprint = {https://erjm.journals.ekb.eg/article_70944_e88a3d50282a965f2ce55b98f6d08110.pdf} } @article { author = {El-kholy, E. E. and shokralla, S. S. and Morsi, A. H. and El-Absawy, Said A.}, title = {IMPROVED PERFORMANCE OF ROLLING MILL DRIVES, USING hyBRID FUZZY-PI CONTROLLER}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {41-57}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2002.70949}, abstract = {In this paper, a fuzzy logic control technique is applied to solve the undesired undershoot that gets the process in special steel rolling mill out of control. Because fuzzy logic controller results in steady state error due to load change two control methods are proposed to improve the hzzy controller performance. The first method uses a fizzy speed controller with a PI current controller and the other method uses a hybrid fuzzy-PI controller. The proposed Hybrid fuzzy-PI controller is applied to a rolling mill drives. This technique can solve the common problems associated with rolling mill drives. The entire drive systems are implemented using a high speed digital signal processor (DSP). Experimental results validate the theoretically simulated responses with different operating conditions.}, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70949.html}, eprint = {https://erjm.journals.ekb.eg/article_70949_c3f9f5ca79ea73f85509401062743201.pdf} } @article { author = {الشاذلي, عاصم محمد}, title = {تأثير مواد البناء التقليدية علي المناخ الداخلي للعمارة في الاقليم الحار}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {59-72}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70951}, abstract = {}, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70951.html}, eprint = {https://erjm.journals.ekb.eg/article_70951_63ee4e506521689837f645c7c22435cb.pdf} } @article { author = {El-Enany, Moustafa A.}, title = {EFFECT OF GEOMETRY COMPUTATIONS AND NUMERICAL SCHEME ON THE RESISTANCE COEFFICIENT FOR UNSTEADY FLOW IN IRREGULAR CHANNELS}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {73-89}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70952}, abstract = {The problem of predicting flow resistance coefficient with sufficient accuracy. is of great interest to hydraulic engineers. Realistic estimate of hydraulic resistance is important to the proper design and analysis of irrigation and drainage networks. Resistance (roughness) coefficient is a compound function of the geometric properties of the channel, the fluid properties, and the varied flow conditions prevalent in the open channel system. The purpose of this study is to demonstrate the response of the applied method of irregular geometric properties computation, the used numerical scheme, and the distance interval adopted in the numerical model on the calibrated value of resistance coefficient. The rectangular grid scheme of the method of characteristics is applied with different methods of irregular geometric properties computation and different value of distance interval. While, the Leap-Frog finite difference scheme is used with only one method of geometric properties computation and one value of distance interval. Measured field data of Tanta Navigation canal are used to feed and calibrate the numerical models. Results of numerical experiments illustrate that inaccurate channel geometry representation in the numerical models leads to incorrect value for the calibrated value of roughness coefficient. Findings also demonstrate that the applied numerical scheme as well as the schematization to describe the channel geomeby by a series of discrete representation along the reach being modeled has significant effect on the calibrated value of the roughness coefficient.}, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70952.html}, eprint = {https://erjm.journals.ekb.eg/article_70952_609aa9f29f88c933e014cbdd4ef01997.pdf} } @article { author = {Ahmed, Sabry A.}, title = {USE OF HOMRA POWDER IN SELF-COMPACTING CONCRETE}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {91-103}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70953}, abstract = {Although 5-10% of the production of clay bricks in Egypt is considered as wastes, their use in concrete is still limited. This study investigates the use of hornra powder as a partial replacement of cement and the influence of the total powder content on the properties of self￾compacting concrete (SCC). The cement content for concrete mixes ranged from 250 to 400 Kg/m3 and that of powdered homra from zero to 150 Kg/m3, in order to obtain a total powder content of 400 Kg/m3. A Viscocrete admixture is introduced in these mixes with three different contents: 1, 1.5 and 2% of the total powder content. In addition to the 400 Kg/m3 total powder content three other contents of 500, 550 and 600 Kg/m3 with 2% of the total powder content superplasticizer are studied and compared with that of 400 Kg/m3. The self￾compactability of concrete is measured by means of slump flow, V-funnel, L-box and resistance to segregation tests. Also the influence on the compressive strength is studied using cubes poured without any internal or external compaction. The results showed that the optimum dosage of Viscocrete admixture in SCC with a total powder content of 400 ~~lm~ is 2% of the total powder content, irrespective of the amount of cement. Addition of homra powder as a partial replacement of cement resulted in a slight reduction in the concrete flowability, noticeable decrease in compressive strength and prolonged initial and final setting times of concrete. The use of high powder content (500-600 Kg/m3) with 2% superplacticizer resulted in a concrete with high flowability and moderate viscosity that are necessary for the successful casting of SCC.}, keywords = {Self-compacting Concrete,Homra Powder,Flowability,viscosity,Compact￾ability,Resistance to Segregation}, url = {https://erjm.journals.ekb.eg/article_70953.html}, eprint = {https://erjm.journals.ekb.eg/article_70953_67bad1d2d4d6730d1ff30cf73f5ccd75.pdf} } @article { author = {Sobeih, M. P. and Rashwan, I. M. H}, title = {DIRECT SOLUTION TO PROBLEMS OF OPEN CHANNEL FLOW FOR VERTICAL TRANSITIONS}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {105-115}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70954}, abstract = {The vertical transition occurred in open channel when the bed goes up or down suddenly or gradually. Such problem could be solved using the specific energy equation. Since the specific energy is measured with respect to channel bed as the datum, a rise or a fall in the bed of the channel causes a decrease or an increase in specific energy. The authors presents in this paper new equations for the solution of ihe vertical transition problems for rectangular open channels. The specific energy in this paper takes a dimensionless form to make the solution of the problem easier. By using the new dimensionless equation, the solution of the two types of vertical transition problems (rise or fall) would be available if the flow through channel subcritical or supercritical. Thus, the new dimensionless equation became very simple in use. Also the new derived cqualions were used to solve the problem if the rise in bed was bigger than the critical rise (maximum rise in bed). From the above it was evident that, if the height of rise in channel bed (hump) was increased further the maximum value and the specific energy held constant with the hump and the discharge would be decreased until the given specific energy was equal to the minimum specific energy corresponding to the new discharge, as the energy could be increased without outside affect. Also, the upstream water depth would be changed to a - new value called }, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70954.html}, eprint = {https://erjm.journals.ekb.eg/article_70954_b1f88445cbbaefe1b92c40df2ff0e855.pdf} } @article { author = {EL-Kholy, E. E. and EL-Sabbe, A. and El-Hefnawy, A. and Mharous, Hamdy M.}, title = {THREE PHASE ACTIVE POWER FILTER BASED ON NEURAL NETWORK OF CURRENT CONTROLLED VOLTAGE SOURCE INVERTER}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {117-133}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70955}, abstract = {This paper presents a shunt active power filter to compensate reactive power and reduce the unwanted harmonics in the supply current. A shunt active filter is realized employing three-phase IGBT bridge based voltage source inverter (VSI) with common DC bus capacitor. Two different proposed control methods for determining the reference compensating currents of the three-phase shunt active power filters based on proportional- integral (PI) controller and Artificial Neural Nepork (ANN) are presented. Current controller based on hysteresis current horitroller is used to generate the firing pulses of VSI inverter. The shunt active filter acts as a current source, which is connected in parallel with a nonlinear load and controlled to generate the required compensation currents. The proposed system is implemented using a high speed Digital Signal Processor (DSP). Experimental and simulation results with different nonlinear loads are presented to conform the validity of the proposed control strategies.}, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70955.html}, eprint = {https://erjm.journals.ekb.eg/article_70955_20c1b6c07bb98227d489f769f66c580c.pdf} } @article { author = {EL-Sabbe, A.}, title = {Load Voltage Stabilization Based On The Series Compensation}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {135-144}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70956}, abstract = {Power factor is related to line current harmonics, many types of filters are used-.to improve the in$t power factor. Some of these circuits are used to eJiminate $e line current harmonics and others are used to compensate the reactive power , hence thqy improves the input power factor. p his paper introduces. a series compensation by using controlled capacitor in series with static /dynamic load. The proposed system improves the input power factor, reduces the input line current harmonics and can be operate as voltage controller to regulate the load voltage without discontinuity in the current. The proposed system can be operated as boost regulator. Hystersise controller and PI ! controller are used to control the power electronic elements operation to control the i capacitor effect. Simulation and experimental results are in good agreement and :show ,!, the effectiveness of the system with static or dynamic loads. j}, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70956.html}, eprint = {https://erjm.journals.ekb.eg/article_70956_1aa9a644486615a417ac7b05723a9355.pdf} } @article { author = {Abd El Razek, M.M.}, title = {THERMAL EXPERIMENTAL INVESTIGATION OF , '' TRADITIONAL HOUSES IN SOUTH EGYPT, (Toshky Region)}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {145-158}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70957}, abstract = {This Paper presents a thermal investigation of four traditional houses tested experimentally under the effect of external climatic conditions of hot dry region in Egypt (Toshky region). The external and internal walls of the test house were constructed from local sandstone blocks with 50 cm thick. The ratio between the external openings and the external walls surfaces areas is less than 10 % . The external wall is covered internally with 2-3 cm cement mortar plasters, while the internal walls covered with 2-3 cm cement plaster from both sides. Volts and domes covered the roof of the test houses. The external surface of the roof covered with 2-3 cm white cement mortar plaster. Results demonstrated that the local building materials (sandstone) suppress the swing of external outdoor air temperature and stabilize the indoor air temperature at average level below the average of outdoor air temperature by about 2-3 OC during the hottest period. The results also show that it is possible to maintain the indoor air temperature significantly below the average of the outdoor air temperature by about 4-5 "C, when modem insulating materials together with the local building materials are used. Besides, the use of passive cooling systems (evaporative cooling) maintained the indoor climate in the thermal human comfort zone.}, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70957.html}, eprint = {https://erjm.journals.ekb.eg/article_70957_0357fb4452d7ecfb18f0ed04e3d95d49.pdf} } @article { author = {Sobeih, M. F.}, title = {DIRECT SOLUTION TO PRACTICAL PROBLEM OF OPEN CHANNEL FLOW FOR HORIZONTAL TRANSITIONS}, journal = {ERJ. Engineering Research Journal}, volume = {25}, number = {4}, pages = {159-169}, year = {2002}, publisher = {Menoufia University, Faculty of Engineering}, issn = {1110-1180}, eissn = {}, doi = {10.21608/erjm.2001.70958}, abstract = {Horizontal transitions are required for economic and practical reasons for irrigation works like bridges, weirs and barrages in natural and artificial open channels. The transitions may be contracting or expanding suddenly or gradually while the flow is I either subcritical or supercritical. The problem is solved using the specific energy i principle. Most of the previous researches solved the problem neglecting the head loss (theoretical solution). The author presents in this research paper a new approach to solve the problem for I horizontal transition for rectangular open channels. i The specific energy equation in this paper takes a real condition in consideration for i both contracting and expanding problems. The practical horizontal transitions cases are ! solved taking into consideration the head loss due to contracting or expanding. Also, this research paper deals with the problem of channel section while contracting with amount greater than that of critical one. If the contraction of bed is increased further, the maximum b, and the specific energy were both held constant with this contraction, the discharge will be decreased until the given specific energy is equal to minimum one corresponding to the new discharge, because the energy cannot be increased without outside affect. Consequently the upstream water depth will be changed to a new value.}, keywords = {}, url = {https://erjm.journals.ekb.eg/article_70958.html}, eprint = {https://erjm.journals.ekb.eg/article_70958_f390f9b21e0fefed8a7c26ef4c770c0c.pdf} }