Papers by hebatalrahman ahmed
مجلة إدارة المخاطر والأزمات, Mar 30, 2020
This research deals with the problem of breakdowns and interruptions and their impact on the indu... more This research deals with the problem of breakdowns and interruptions and their impact on the industrial system in iron and steel industry, which considered as one of the industries related to the construction sector and automotive industries. The research is an applied study on the hot rolling mill factory of the Libyan Iron and Steel Company in Misurata. The study introduce analysis for maintenance programs and their economics related to breakdown and breakdown rates in the hot rolling factory in Misurata, which is the main producer of steel reinforcement and steel bars in the Libyan Jamahiriya. Malfunctions and breakdowns are studied through annual statistics reports stops in the previous years of the life of the factory, The effects of mechanical stops on the annual production amount in the factory were estimated and calculated statically, the research also discuss many concepts and strategies for new maintenance operations such as maintenance before malfunctions such as predictive maintenance and periodic maintenance. The research end with group of conclusions and recommendations for the methods to overcome the problems of stoppages and breakdowns in steel mills, it is establish a strategy for counting, assessing faults and developing maintenance systems in proportion to the age of the plant.
Microelectronic Engineering, Jun 1, 2004
Journal of Physics: Conference Series
In this work the nonlinear optical characteristics of sand glass which is the origin of quartz cr... more In this work the nonlinear optical characteristics of sand glass which is the origin of quartz crystal were evaluated, sand glass particles from mining site waste were prepared by washing, drying, magnetic separation and sieving. The particles are soaked in sulphonic acid H2 SO4 acidic solution with 30% concentration for 100 hours, the new compound with optical characteristics was formed at different volume fractions of sandglass such as 20%,40%,60%, and 80% respectively. The new machine was developed for manufacturing the new compound from sand glass. The optical nonlinear absorption coefficient of the sand glass-ceramics material was investigated using the Z-scan technique, provided with nanosecond pulses of second harmonic (green Nd:YAG laser with 532nm wavelength). The effect of lattice structure and particles concentration on the non-linear optical properties were also discussed. The conclusions and recommendations for the best material and concertation for nonlinear optical ma...
International Journal of Thin Film Science and Technology, 2021
In this work, New composite material was developed from marble and granite waste , the unit for r... more In this work, New composite material was developed from marble and granite waste , the unit for recycling of marble and granite wastes was designed, the prototype was tested in manufacturing of thermoplastic based composite from marble and granite wastes respectively, the main characteristics of both composite materials were measured, the structure of the new composite materials were determined by SEM, the composition were determined by EDX analysis, the particle size and elemental analysis were evaluated by the same technique, the volume resistivity and abrasive wear was evaluated. Thermogravimetric Analysis (TGA) was measured to determine the operation temperature of the new composite materials. Thermal conductivity of new composite material was calculated from the role of mixture. The main applications of the new composite materials were mentioned according to the characteristics measured.
Risk assessment are essential for professional success in any workplace and infrastructures prote... more Risk assessment are essential for professional success in any workplace and infrastructures protection and operation. Structured risk assessment instruments are frequently used to aid in a number of decisions. With hundreds of available risk assessment tools and a steadily growing literature on their utility, it is important to examine possibilities for protective and pre maintenance. The present article provides qualitative and quantitative analysis for risks related to infrastructure in Egypt to specify the factors affecting this fields which affect on development and safety of the country. The technique is not only suitable for infrastructure risks but also very good guidance for any risk or crisis in construction field, it treats the risk assessment during construction period and during operation, the precautions related to infrastructur management and use are mentioned with the required equipment and utensils. infrastructure risk assessment in Suez Canal will be considered as case study in this work, it is considered as an example of green infrastructures. There are major risks to the economic viability of large-scale infrastructure projects such as the New Suez Canal.
In this work, New composite material was developed from marble and granite waste , the unit for r... more In this work, New composite material was developed from marble and granite waste , the unit for recycling of marble and granite wastes was designed, the prototype was tested in manufacturing of thermoplastic based composite from marble and granite wastes respectively, the main characteristics of both composite materials were measured, the structure of the new composite materials were determined by SEM, the composition were determined by EDX analysis, the particle size and elemental analysis were evaluated by the same technique, the volume resistivity and abrasive wear was evaluated. Thermogravimetric Analysis (TGA) was measured to determine the operation temperature of the new composite materials. Thermal conductivity of new composite material was calculated from the role of mixture. The main applications of the new composite materials were mentioned according to the characteristics measured.
Egypt is considered as one of the most affected countries by different risks expected due to glob... more Egypt is considered as one of the most affected countries by different risks expected due to global warming. The United Nations (UN) reports mentioned Egypt as one of the five countries that will suffer from negative effects due to climate changes (UNFCCC, 2020), (Le Quéré, C and et al., 2019). The temperature and humidity lead to changing patterns of rainfall, rising sea levels, and the increasing frequency of climate-related disasters. Climate changes have both negative and positive effects on the production of crops besides the economy of agriculture projects (Roelfsema M.and et al, 2020). As well as the expected scenarios effect of climate changes on the cultivated area in Egypt, As well as the expected scenarios effect of climate changes on the cultivated area in Egypt, the real estate wealth and buildings, will also be affected by different global climate changes phenomena. the total amount of greenhouse gases evaluated in Egypt was about 197 million tons of carbon dioxide equivalent in 2013/2014. The dangerous of sinking and salinity in the Nile delta 10-15% due to rise in the water level of the Mediterranean Sea half-meter average will lead to changes in demography and population distribution in Egypt (Hausfather, Z. and Peters, G. P., 2020), (United Nations, Climate actions, 2020), the available water resources will be reduced by approximately 17.88 billion cubic meters, equivalent to 20% of the available water resources in the case of the sinking parts of the delta, the expected resource of water available is about 80.4 billion cubic meters, the shortage in water will affect all fields such as industrial and medical (William J. Ripple, 2020), the quality of life is a strong function in the quality of water, all expected possible scenario of the impact of climatic changes must be prepared till 2030 (United Nations Framework Convention on Climate, 1992), (J.A. Duffie and W.A. Beckman, 2006). The completion of the severe shortage of available data and information on the negative effects of climate change on different sectors of development in Egypt is the most important step to prepare real and effective scenarios to deal with the risks of climate change (Paulescu, E. and et al, 2013), (Solar Spectram 2019). Natural disasters result from climate changes such as heavy rains, volcanoes, torrents, floods, desertification (M. Sengupta and A. Andreas, 2010). earthquakes, landslides, wind, and hurricanes were discussed. The different features of climate change that occurred during a specified previous period are evaluated to investigate the impact of different climates (Masson-Demotte, V. P and et alm 2021), (Li, C. Luoyang, 2021). The Key items of climate change until 2050 such as Global warming as a result of the widening of ozone holes, temperatures, and humidity increase leading to heat weaves and storms were mentioned, the rising in water levels in the Mediterranean Sea is considered as one of the most important features of the climate changes the rise of the sea level affect the climate change on the medium and long term (Brady, K. , 2021), (Stojanovic, M. , 2021).
Egypt is considered as one of the most affected countries by different risks expected due to glob... more Egypt is considered as one of the most affected countries by different risks expected due to global warming. The United Nations (UN) reports mentioned Egypt as one of the five countries that will suffer from negative effects due to climate changes (UNFCCC, 2020), (Le Quéré, C and et al., 2019). The temperature and humidity lead to changing patterns of rainfall, rising sea levels, and the increasing frequency of climate-related disasters. Climate changes have both negative and positive effects on the production of crops besides the economy of agriculture projects (Roelfsema M.and et al, 2020). As well as the expected scenarios effect of climate changes on the cultivated area in Egypt, As well as the expected scenarios effect of climate changes on the cultivated area in Egypt, the real estate wealth and buildings, will also be affected by different global climate changes phenomena. the total amount of greenhouse gases evaluated in Egypt was about 197 million tons of carbon dioxide equivalent in 2013/2014. The dangerous of sinking and salinity in the Nile delta 10-15% due to rise in the water level of the Mediterranean Sea half-meter average will lead to changes in demography and population distribution in Egypt (Hausfather, Z. and Peters, G. P., 2020), (United Nations, Climate actions, 2020), the available water resources will be reduced by approximately 17.88 billion cubic meters, equivalent to 20% of the available water resources in the case of the sinking parts of the delta, the expected resource of water available is about 80.4 billion cubic meters, the shortage in water will affect all fields such as industrial and medical (William J. Ripple, 2020), the quality of life is a strong function in the quality of water, all expected possible scenario of the impact of climatic changes must be prepared till 2030 (United Nations Framework Convention on Climate, 1992), (J.A. Duffie and W.A. Beckman, 2006). The completion of the severe shortage of available data and information on the negative effects of climate change on different sectors of development in Egypt is the most important step to prepare real and effective scenarios to deal with the risks of climate change (Paulescu, E. and et al, 2013), (Solar Spectram 2019). Natural disasters result from climate changes such as heavy rains, volcanoes, torrents, floods, desertification (M. Sengupta and A. Andreas, 2010). earthquakes, landslides, wind, and hurricanes were discussed. The different features of climate change that occurred during a specified previous period are evaluated to investigate the impact of different climates (Masson-Demotte, V. P and et alm 2021), (Li, C. Luoyang, 2021). The Key items of climate change until 2050 such as Global warming as a result of the widening of ozone holes, temperatures, and humidity increase leading to heat weaves and storms were mentioned, the rising in water levels in the Mediterranean Sea is considered as one of the most important features of the climate changes the rise of the sea level affect the climate change on the medium and long term (Brady, K. , 2021), (Stojanovic, M. , 2021).
In this work, new composite material is manufactured from poly(methyl methacrylate) PMMA matrix r... more In this work, new composite material is manufactured from poly(methyl methacrylate) PMMA matrix reinforced by glass fibre type E-glass. The effect of volume fraction of fibre and length to diameter ratio is studied, and friction and wear characteristics were determined at different volume fractions and fibre sizes. The hardness and wear resistance of randomly distributed PMMA matrix composite were significantly enhanced, and the maximum conditions for reinforcement of PMMA matrix composite to improve tribology characteristics were evaluated. The effect of laser irradiation on the mechanical properties was evaluated by irradiation of composite material after manufacturing, with different kinds of lasers. The continuous wave (CW) argon-ion laser and pulsed Nd:YAG laser were used to irradiate composite material. Hardness, wear rate, and coefficient of friction were evaluated at the same test condition of the unirradiated composite. The significant improvement in improvement in the mechanical properties at certain irradiation conditions was evaluated.
In this work, new nano and micro thermoplastic-based composites are prepared with zeolite filler,... more In this work, new nano and micro thermoplastic-based composites are prepared with zeolite filler, the method involves using zeolite in powder form, the preparation of zeolite powder from ores by crushing it into small-sized granules. The characteristics of the zeolite powder are determined. The physical properties and chemical composition (XRD) are evaluated before impeding it into the thermoplastic. Thermoplastics powder is added to the zeolite powder as granules in different sizes, the particles sizes ranging from the size of a millimeter to a nanometer. The manufacturing quality parameters are optimized at volume percentages of filler in the range of 20 to 25%, composite material is formed into molds. New Composite material is characterized by easy deformation into different shapes besides machineability. The characteristics of new composites such as SEM, EDX, and FTIR in absorption and transmission mode are evaluated and compared with the standard characteristics of Zeolite ores. The performance and characteristics of the new composite are completely different. The new composite is hard, solid, and does not absorb water.
In this work the nonlinear optical characteristics of sand glass which is the origin of quartz cr... more In this work the nonlinear optical characteristics of sand glass which is the origin of quartz crystal were evaluated, sand glass particles from mining site waste were prepared by washing, drying, magnetic separation and sieving. The particles are soaked in sulphonic acid H 2 SO 4 acidic solution with 30% concentration for 100 hours, the new compound with optical characteristics was formed at different volume fractions of sandglass such as 20%,40%,60%, and 80% respectively. The new machine was developed for manufacturing the new compound from sand glass. The optical nonlinear absorption coefficient of the sand glass-ceramics material was investigated using the Z-scan technique, provided with nanosecond pulses of second harmonic (green Nd:YAG laser with 532nm wavelength). The effect of lattice structure and particles concentration on the non-linear optical properties were also discussed. The conclusions and recommendations for the best material and concertation for nonlinear optical material were mentioned. The research end with conclusions and recommendation for the development of new optical materials based on micro and nanoparticles from natural resources.
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Papers by hebatalrahman ahmed