Estimation of the reliability for repairable system after maintenance actions is usually based on mathematical models, which can be classified as parametric and non-parametric models where the parametric model is required a prior specified life time distribution while Non-parametric model is that relaxes of the assumption of the life time distribution. Nonparametric life time models are including proportional hazard model and proportional odd model. In this paper we develop repairable reliability model concentrate on generalized repairable model that indicate the mixture of proportional hazard model and proportional odd model. A proportional hazard-proportional odds (PH-PO) model for the purpose of to improve the repairable reliability to obtain accurate estimates of reliability for repairable industrial boiler system at normal operating conditions depending on transformation parameter for reliability prediction for repairable system that represent Beji industrial boiler in power plant. The results show the odd model better than hazard model for repairable system after preventive maintenance depends on time to repair where transformation parameter (c) equal 0.0525094 it is closer to odds model than hazard model. In addition, reliability industrial boiler in case without temperature effect is better than reliability with temperature effect by using exponential model where we note that the reliability at 500 it is worse state where degrade more than (400,450) .
Recently, the sustainability issue has become crucial to operation, which motivates researchers to search for naturally generated, sustainable materials, especially in automotive applications outside of reduced prices and enhanced performance. Glass-linen/Polyvinyl Butyral hybrid composites' mechanical characteristics were examined in relation to the effect of linen fiber loading. The composite and hybrid composite samples of linen/glass fiber reinforced PVB film were created using a hot press with various layering patterns. The results were high impact values with increased both tensile and flexural strength values. Compared to other hybrid composites, the mechanical behaviors of the H1 (Glass / Linen) hybrid have a greater tensile strength measuring 401.30 MPa, while, H2 (Glass / Linen/ Glass) hybrids are found to have the highest flexural strength, measuring 160.80 MPa. An optical and scanning electron microscope morphological analysis on linen hybrid composites revealed good results. This indicated decreased rates of delamination between the fibers and matrix layers. The loading of the fibers was shown to have varying effects on the composite's mechanical behaviors. The linen/glass composites also demonstrated strong interfacial adhesion, which enabled the PVB-phenolic resin to penetrate the fiber bundles and produce a matrix with the good interlocking of the fibers
This work aims to increase the availability of steam generation plant through modifying boiler maintenance plan by determining the optimum period of time between maintenances to achieve maximum availability via simulation approach. Applying simulation approach is an attempt to determine the optimum period of time between schedule maintenances to achieve maximum boiler availability. Therefore, PC program in visual basic language is designed as a tool to the implementation of availability simulation approach. It notes that the boiler availability is increased by (6.9%) in changing the optimum time between scheduled maintenances and inspection to be seven months rather than one year
This new methodology utilizes Quality Function Deployment (QFD) with Analytic Hierarchical Process (AHP) together for improving product planning stage, hence, the product development, because this stage precedes the manufacturing stage and is regarded as an important stage in the product development. The proposed methodology consists of two models; namely: (1) Curent QFD Model. (2) Current AHP Model. It was applied practically to demonstrate the models' applicability and suitability, and develop liquid Gas Cylinder Valve produced at Al-Ikhaa General Company (IGC) for Mechanical Industries. "Thus it was possible to find out the critical and important specifications for improving product planning which should be considered in product development". These specifications have high ranking and Scaled Value Technical Ratings (SVTR) of over (50%). SVTR have values as follows: (1) (1.0000) for Pad (H1), then (2) (0.9270) for piston (H4), (3) (0.9195) for gasket (H12), (4) (0.8236) for safety valve (H6), (5) (0.8156) for sealing 1 (H5), (6) (0.6935) for sealing 2 (H9), (7) (0.5441) for installing the regulator with valve (H10) and (8) (0.5220) for spring2 (H7). When applying AHP method, various results were obtained. Based on the final score of Al-Ikhaa Company, where the highest defects value was (45%) was reported in the production processes. Also, values of maintenance dismantling 23%, Product assemblage 12% and maintenance assemblage 9% of the Product values.
The increasing price of fossil derivatives, global warming and energy market instabilities are a major problem. In recent years, these problems led to an increasing using of renewable energy sources such as wind energy. Wind turbine used to extract this energy from the wind to produce power or electricity. Due to low cost, easy for maintenance and it is, portability the most com-monly used among wind turbines is small axis wind turbine. Analysis to optimization power coef-ficient ( ) of a small wind turbine blade design model (Primus Wind power AIR 40 Wind Tur-bine 12VDC) are evaluated and discussed in this study. A shape of blade wind turbine is the pri-mery parapeter affected the power output of wind turbine. In this type of turbine NACA2411 used as the blade airfoil as represent shape of blade. For this goal, 185 different airfoils selected. For this purpose, using the XFOIL software to simulate the properties of each airfoil at Re (1.0*105, 1.5*105, 2.0*105, 2.5*105, 3.0*105 and 3.5*105) and angle of attack from 0˚ to 10˚, Then elimination criteria was performed for removing those airfoils would not suitable for the purpose up on their effiency. At the end of analysing Matlab software used for calculate the power coeffi-cient and selecting the best airfoils design for used manufacture anew blade for that type of small wind turbine with better power coefficient. The output of XFOIL and matlab software showed by tabulates and graphs. As a results show 3 airfoils were selected due to their performance better than other airfoils from an initial group of 185 as exemplification of the methodology namely S1210,SD7034 and S2091, The maximum that has been achieved by which used airfoil S1210 equal to 0.52 at Re 350000.
The concrete members several blessings over steel beam, like high resistance to prominent tem-perature, higher resistance to fatigue and buckling, high resistance to thermal shock, fire re-sistance, robust resistance against, and explosion. However there are some disadvantages as a result of exploitation totally different materials to product it. The most downside of structural concrete member is its deprived the strength to tensile stresses.The bond mechanism between steel bars and concrete is thought to be influenced by multiple parameters, like the strength of the encompassing media, the prevalence of cacophonous cracks within the concrete and therefore the yield stress of the reinforcement. However, properties of concrete mass has significantly effect when it was subjected to elevated temperature.The objective of this paper presents the results that allocating with the bond behavior of the rein-forcement of steel bar systems below static pull-out loading tests subjected to elevated tempera-tures. This numerical technique relies on relative slip and therefore the stress of bond distribu-tions done the embedded length and size of the bar within the concrete cylinder specimens. The obtained results square measure given and commented with the elemental characteristics of ferroconcrete members. The comparison showed smart agreement with experimental results
Materials selection is a multi-criteria decision-making (MCDM) problems because the large numberof factors affecting on decision making. The best choice of available material is critical to thecompetitiveness and success of the manufacturing organisation. The analytical hierarchy process(AHP) is an important tool to solve MCDM problems. The choosing process of suitable material(such as a refrigerant fluid) for the Air Condition System (ACS) is faced with challenges such aslack of a systematic approach in setting the optimal performance in terms of its impact on theenvironment and operation. Selecting process for the one refrigerant from a range suitable ofsuitable refrigerant is complex process. The study presents a comparative performance analysisof ACS for using four alternative refrigerants R290, R410, R404 and R22. Then, one of these suitablerefrigerant is selected. The comparison is based on three criteria system operation, environmentand maintenance.Novels ACS performance assessment model is proposed based on an analytical hierarchy process(AHP). The model is based on two main criteria of ACS, quantitative criteria, cooling capacity(CC), coefficient of performance (COP), etc.).And qualitative criteria (Ozone Depletion Potential (ODP), Global Warming Potential (GWP) andmaintenance cost (MC)). It is necessary to look for new technique help decision making to selectalternative refrigerants, to fulfill the goals of the international protocols (Montreal and Kyoto)and optimum operation, to satisfy the growing worldwide demand, in addition the increase outdoortemperature in some countries.This study provides a developed methodology for evaluating ACS performance. Moreover, it helpsto select a robust decision. The results obtained from AHP process that the best rank of the suitablerefrigerant was R404 (0.3763) followed by R22 (0.3657) and so on for the other. Therefore,the proposed methodology can help the decision maker to select the best alternative for bothcriteria (qualitative and quantitative) in complex selecting process.
ORE addresses various kinds of losses associated with manufacturing system which can be targeted for initiating improvements. Evaluating ORE will is helpful to the decision maker(s) for further analysis and continually improves the performance of the resources. Overall Resource Effectiveness (ORE) encompasses seven factors are; performance, quality rate, readiness, changeover efficiency, availability of material and availability of manpower. In this research Job shop production of General Company for hydraulic industries, with focus on Damper and Tasks Factory (DTF)is tested as a case study for two of the most customer demand rear dampers (Samaned and Nissan). Data are collected and analyzed for years 2016-2017 to evaluate of ORE values. Results show that process performance factor among other seven factors have the less value causing the highest loss in ORE decrease. Where the highest ORE value is (58.6%) for Nissan and (69.3) for Samaned rare production. Also, time loss due to set up time is detected where it ranges from 3% to about 13% per month for the above mentioned two tested dampers. Results are generated employing Minitab Version 17, Quality Companion Version 3 soft wares. It is recommended to introduce SMED (Single Minute Exchange of Dies) concept that could decrease losses in set up time .Also improvements in maintenance programs are vital, and above all improving process performance values is essential by employing lean manufacturing that result in fast outcomes ,and TQM process improvement strategy for long term outcomes these two process performance strategies may enhance ORE values therefore, decrease losses, and consequently increase quality and productivity.
The scientific paper examined the possibility of developing an advanced healthcare management system in Iraq through the use of Cisco Packet Tracer software. The article stated that the aforementioned software has the potential to speed up network management operations and reduce expenses incurred in maintenance and repair activities. In addition, the article explained several challenges that may arise during the implementation of the smart hospital management system, including providing the required technical expertise, infrastructure provisions, and procedural measures necessary to protect the confidentiality of patient and employee information. The study confirmed that implementing an intelligent hospital management system in Iraq has the potential to improve healthcare quality, mitigate medical errors, enhance employee communication, and reduce disturbances within the hospital setting. Furthermore, this intervention is expected to enhance the efficiency of resource and inventory management and increase patients' experience and satisfaction with healthcare services. The article concludes that achieving the desired results in implementing a smart hospital management system using Cisco Packet Tracer software depends on the collaborative contributions of employees, managers, and technical professionals. This initiative is expected to enhance the hospital's ability to provide medical services of exceptional quality and effectively meet the diverse needs of patients.